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Selected AbstractsTrials update in walesCYTOPATHOLOGY, Issue 2007A. Fiander Three ongoing studies will be presented and discussed. Prevalence of Human Papillomavirus Infection in a South Wales Screening population Methods: A total of 10 000 consecutive, anonymous liquid based cytology screening samples were collected over a five month period in 2004. Age, cytology result and social deprivation score was provided for each specimen. The methodology was chosen to ensure inclusion of all women attending routine cervical screening, avoiding potential constraints associated with obtaining individual informed consent. The liquid based cytology samples were processed and reported by the receiving cytology laboratory and the residual specimens sent to the HPV Research Laboratory, Wales College of Medicine, where they were processed and stored at -80°C until analysis. High risk and low risk HPV Typing was undertaken using PCR , EIA (Jacobs et al 1997). Full high risk typing was performed on HPV positive specimens. Results: The study population had a mean age of 38 years with 92% negative, 5% borderline and 3% dyskaryotic cytology. The average social deprivation score was 17.4 (based upon the Welsh Index of multiple deprivation). The following results will be presented: HPV prevalence by age. HPV prevalence by cytology result. Type specific HPV prevalence in single and multiple infection. Conclusion: This study represents the largest type specific HPV Prevalence Study in the UK to date. As such it will form a useful base line against which to access performance of marketed HPV tests and evaluating the impact following implementation of HPV vaccination. [Funded by Welsh Office for Research and Development] CRISP , 1 Study (Cervical Randomized Intervention Study Protocol -1) Background: Indole-3-carbinol (I3C) and Diindolylmethane (DIM) are found in cruciferous vegetables and have been identified as compounds that could potentially prevent or halt carcinogenesis. I3C spontaneously forms DIM in vivo during acid digestion. I3C has been shown to prevent the development of cervical cancer in HPV 16 transgenic mice and both I3C and DIM have been shown to promote cell death in cervical cancer cell models. DIM is the major active bi-product of I3C and preliminary data indicate that DIM is active in cervical dysplasia and may be better tolerated than I3C. Aim: To investigate chemoprevention of high grade cervical neoplasia using Diindolylmethane (DIM) supplementation in women with low grade cytological abnormalities on cervical cytology. Objectives: To observe any reduction in the prevalence of histological proven high-grade cervical intraepithelial neoplasia (CIN) after 6 months of supplementation. ,,To observe any reduction in the prevalence of cytological abnormalities. ,,To observe any changes in the clinical appearance of the cervix. To assess acceptability and monitor any side effects of DIM supplementation. ,,To assess whether any benefit is seen in relation to Human Papillomavirus (HPV) status including HPV Type, Viral load and integration. Methods: This is a double blind randomized placebo-controlled trial involving 600,700 women with low grade cytological abnormalities on a cervical smear. Randomization is in the ratio of 2 : 1 in favour of active medication. Women with first mildly dyskaryotic smear or second borderline smear are eligible. They are asked to take two capsules daily for 6 months. At the end of 6 months they undergo repeat cervical cytology, HPV testing and colposcopy. Results: A progress report will be given for this ongoing study. [Funded: - Cancer Research UK] Type Specific HPV Infection in Welsh Cervical Cancers Background: Whilst there have been numerous studies of HPV infection associated with cervical cancer and on prevalence of Human Papillomavirus in diverse populations there have been no studies of these variables in the same population. Against a background of prophylactic HPV vaccination it is important to assess potential protection against cervical cancer within a given population. The most comprehensive analysis of HPV type specific cervical cancer is a meta-analysis published by the IARC in 2003. This however included only three UK based studies, totalling 118 cases, 75 of which were only investigated by HPV type PCR for four high risk types. None of this data was presented with associated population based prevalence data. Therefore, the research objectives for this study in combination with the first study above, are as follows: To determine the frequency of specific HPV types in cervical cancers in Wales. To compare the distribution of specific HPV types amongst cervical cancers with their prevalence in the general population. This will allow accurate delineation of the relationship between prevalence of specific HPV types in the general population and their association with clinically relevant disease. This information is a pre-requisite to assess the potential impact of prophylactic vaccination against HPV infection in Wales. Methods: Welsh Cervical Cancer specimens from 2000,2005 will be identified from pathology departments within Wales. The pathology of each tumour will be reviewed by a single Gynaecological Pathologist. The age of the patient and pathological features of the tumour will be noted. DNA will be extracted from the paraffin sections and HPV typed by PCR-EIA. Results: A progress report will be given for this ongoing study. [Funded by Welsh Office for Research and Development] [source] Dermal fibroblasts contribute to multiple tissues in the accessory limb modelDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 4 2010Ayako Hirata The accessory limb model has become an alternative model for performing investigations of limb regeneration in an amputated limb. In the accessory limb model, a complete patterned limb can be induced as a result of an interaction between the wound epithelium, a nerve and dermal fibroblasts in the skin. Studies should therefore focus on examining these tissues. To date, however, a study of cellular contributions in the accessory limb model has not been reported. By using green fluorescent protein (GFP) transgenic axolotl tissues, we can trace cell fate at the tissue level. Therefore, in the present study, we transgrafted GFP skin onto the limb of a non-GFP host and induced an accessory limb to investigate cellular contributions. Previous studies of cell contribution to amputation-induced blastemas have demonstrated that dermal cells are the progenitors of many of the early blastema cells, and that these cells contribute to regeneration of the connective tissues, including cartilage. In the present study, we have determined that this same population of progenitor cells responds to signaling from the nerve and wound epithelium in the absence of limb amputation to form an ectopic blastema and regenerate the connective tissues of an ectopic limb. Blastema cells from dermal fibroblasts, however, did not differentiate into either muscle or neural cells, and we conclude that dermal fibroblasts are dedifferentiated along its developmental lineage. [source] Effects of size and morphology on swimming performance in juvenile brown trout (Salmo trutta L.)ECOLOGY OF FRESHWATER FISH, Issue 4 2003A. F. Ojanguren Abstract,,, Our study assesses swimming capacity (speed and stamina) and possible morphometric determinants of locomotor performance of juvenile brown trout (Salmo trutta L.). We addressed these issues at the individual level to have an approach of the functional significance of intraspecific variation in morphological design. Both swimming speed and endurance time showed significant positive relationships with fish length. Size-corrected values of speed and endurance time were negatively correlated suggesting a phenotypic trade-off between burst and prolonged swimming. Size was also highly correlated with all the morphological variables measured. Therefore, we used the residuals of the regressions of those variables on fish length to remove the effect of body size. A principal components analysis (PCA) summarised the 12 morphological variables into two factors, which accounted for 44.3% of the variance. PC1 combined several measures of body depth and width, whereas PC2 represented mainly postanal length relative to abdomen length. Relationships between the scores of the two factors and size-corrected values of maximum swimming speed and endurance time were weak. PC2 showed a significant positive relationship with endurance time; that is, individuals with longer caudal regions were able to swim against water flow for longer periods of time. Stoutness (PC1) showed a marginally significant negative correlation with endurance time. The lack of stronger relationships could be because of the low morphometric variability among the test individuals, all proceeding from the same population, reared in a common environment, and measured at the same ontogenetic stage. [source] Integrated condition indices as a measure of whole effluent toxicity in zebrafish (Danio rerio)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2002Roel Smolders Abstract Toxic exposure of organisms interferes with organismal integrity at the biochemical level and ultimately gives rise to effects at the individual level. These effects may result in reductions in ecologically relevant characteristics such as growth, reproduction, and survival. A chronic toxicity test with zebrafish (Danio rerio) was conducted where fish were exposed to 50, 75, and 100% effluent for 28 d under flow-through conditions. Effects of effluent exposure were determined using endpoints of physiological (respiration during swimming), growth (condition, length, and weight), and reproductive (spawning and hatching) processes within the same population. Results clearly indicate that the condition and growth of zebrafish is depressed by exposure to the effluent. Also, increased oxygen consumption was found after 14, 21, and 28 d of exposure. Reproduction proved to correlate well with the condition of the motherfish in the control, and spawning and hatching were significantly depressed by effluent exposure. These results indicate that the evaluation of endpoints describing different ecologically relevant processes provides a rational assessment of the cause,effect relationships of effluent toxicity. This approach can quantify effects on different biological processes and can determine the interactions that occur between these different processes. [source] Depression and Altered Quality of Life in Women with Epilepsy of Childbearing AgeEPILEPSIA, Issue 1 2004Ettore Beghi Summary: Purpose: To calculate the prevalence of depression in a referral population of women of childbearing age, to define the factors associated with depression, and to assess health-related quality of life (HRQOL) in the same population. Methods: The 642 consecutive women with epilepsy aged 18,55 years were enrolled by 40 neurologists over an 8-month period and asked to give details on selected demographic and clinical features regarding the disease, any associated clinical condition, and any drug treatment. Depression was diagnosed by using the Hamilton depression scale and HRQOL was measured through the SF-36 form. Demographic, clinical, and therapeutic risk factors for depression were searched for within the study population. Results: Depression (any severity) was present at interview in 242 women, giving a prevalence rate of 37.7%[95% confidence interval (CI), 33.9,41.6]. Mild depression was reported by 18.5% of women, moderate depression by 8.6%, major depression by 10.3%, and severe depression by 0.3%. Factors found to be independently associated with depression (any severity) included treatment of associated conditions [relative risk (RR), 1.5; 95% CI, 1.2,1.8), concurrent disability (RR, 1.3; 95% CI, 1.0,1.6), seizures in the preceding 6 months (RR, 1.4; 95% CI, 1.1,1.7), and being unemployed or a housewife (RR, 1.3; 95% CI, 1.0,1.5). Factors associated with moderate to severe depression included treatment for associated conditions (RR, 2.0; 95% CI, 1.4,2.7), seizures in the preceding 6 months (RR, 1.7; 95% CI, 1.2,2.5), and being unemployed or a housewife (RR, 1.6; 95% CI, 1.1,2.2). Compared with normal women of similar age, patients with epilepsy tended to present lower scores for each HRQOL domain (mostly Role Physical, General Health, Social Functioning, and Role Emotional). However, when the analysis was limited to nondepressed women with epilepsy, any difference disappeared. Conclusions: Women with epilepsy of childbearing age are at high risk of depression. Factors associated with depression include lack of occupation, the presence of an underlying disabling condition (with treatment), and the severity of epilepsy. Compared with the general population, depressed women have greater impairment of HRQOL with epilepsy, which reflects the physical, social, and emotional implications of the disease. [source] Premating Avoidance of Inbreeding Absent in Female Guppies (Poecilia reticulata)ETHOLOGY, Issue 7 2006Åslaug Viken The recognition and avoidance of kin during mating can be an important means of reducing the potential for inbreeding depression in offspring. We report here that premating mechanisms to avoid inbreeding, either innate or learnt through juvenile experience, are at best weak in female guppies (Poecilia reticulata). Guppies are small, ovoviviparous, neo-tropical freshwater fish, with a polygamous mating system where males actively court females and females are selective of their mates. In a series of mate-choice experiments, naïve, virgin females of the Quare River population in Trinidad were given a choice between a brother and a non-sib male from the same population. Initially, females were only provided olfactory cues upon which to base their choice and then subsequently both olfactory and visual cues. Despite the females displaying mate choice, we found no evidence of them discriminating between the male types in either experiment. There was thus no indication of inbreeding avoidance, suggesting that experiences after maturation or with mature males (e.g. rare male preference), dispersal and/or post-mating mechanisms may be evolutionarily more important avoidance mechanisms. [source] Temporal and Geographic Variation in the Advertisement Call of the Booroolong Frog (Litoria booroolongensis: Anura: Hylidae)ETHOLOGY, Issue 12 2005Michael J. Smith The mechanisms that underlie sexual selection rely upon within- and among-individual variability in the targeted traits. In this study, we examined variation in the advertisement call of the booroolong frog (Litoria booroolongensis) at several different levels: between populations, between breeding seasons in the same population, among males within a population, within males between nights and within males in a single calling bout. The call of L. booroolongensis has multiple notes with a pulsed structure. We detected considerable variation in advertisement call structure between breeding seasons and between populations. The measured call properties ranged from static to dynamic; however, most properties were intermediate between the criteria that have been traditionally used to define call traits as static or dynamic (,5 and ,12% respectively). We compared actual and relative repeatabilities and found that the temporal call properties associated with the structure of the note had the highest values, suggesting that these characters in particular may respond to selection. We argue that relative repeatabilities are a particularly useful measure of the potential for evolutionary response to selection as they account for an individual's relative performance during the period of assessment in an ever-changing breeding arena. [source] Age-Related Microhabitat Segregation in Willow Tit Parus montanus Winter FlocksETHOLOGY, Issue 11 2000Lluís Brotons It is expected that through flexibility in behaviour, flock living birds respond to the asymmetries in resource access derived from dominance relationships. We analysed the microhabitat use of willow tits in winter flocks and assessed possible factors which shape habitat segregation between adults and juveniles in different temperature regimes. When foraging in mild conditions (ambient temperature >,0°C), flocks split up into subgroups with adults foraging in inner parts of trees more often than juveniles. However, no differences were recorded in the vertical position occupied in trees. In harsh conditions (< , 4°C), flocks re-united and juveniles further moved to outer parts of trees, increasing horizontal segregation between age classes. In mild conditions, vigilance behaviour was not related to the position of birds in trees, but in harsh conditions, scanning frequency was higher in outer parts of trees only for adults. In mild weather, juvenile position in trees was associated with body size and mass. The foraging microhabitat segregation detected in harsh conditions fits the age-related hoarding distribution previously described in the same population. This supports the hypothesis that hoarded food is important in determining future foraging habitat use. Adult preference and intraspecific competition for safer or richer inner parts of trees as foraging sites during harsh conditions seems to determine the habitat segregation between adults and juveniles. Furthermore, we suggest that in mild weather, when foraging in the absence of adults, juveniles balance the costs of using a potentially dangerous microhabitat with the benefits of building energetically cheap and large food reserves through hoarding. The expected patterns of microhabitat segregation may differ in parids, depending on whether predation risk or other factors such as food availability are the main factors controlling habitat quality. [source] Lineage analysis of quiescent regenerative stem cells in the adult brain by genetic labelling reveals spatially restricted neurogenic niches in the olfactory bulbEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2009Claudio Giachino Abstract The subventricular zone (SVZ) of the lateral ventricles is the major neurogenic region in the adult mammalian brain, harbouring neural stem cells within defined niches. The identity of these stem cells and the factors regulating their fate are poorly understood. We have genetically mapped a population of Nestin-expressing cells during postnatal development to study their potential and fate in vivo. Taking advantage of the recombination characteristics of a nestin::CreERT2 allele, we followed a subpopulation of neural stem cells and traced their fate in a largely unrecombined neurogenic niche. Perinatal nestin::CreERT2 -expressing cells give rise to multiple glial cell types and neurons, as well as to stem cells of the adult SVZ. In the adult SVZ nestin::CreERT2 -expressing neural stem cells give rise to several neuronal subtypes in the olfactory bulb (OB). We addressed whether the same population of neural stem cells play a role in SVZ regeneration. Following anti-mitotic treatment to eliminate rapidly dividing progenitors, relatively quiescent nestin::CreERT2 -targeted cells are spared and contribute to SVZ regeneration, generating new proliferating precursors and neuroblasts. Finally, we have identified neurogenic progenitors clustered in ependymal-like niches within the rostral migratory stream (RMS) of the OB. These OB-RMS progenitors generate neuroblasts that, upon transplantation, graft, migrate and differentiate into granule and glomerular neurons. In summary, using conditional lineage tracing we have identified neonatal cells that are the source of neurogenic and regenerative neural stem cells in the adult SVZ and occupy a novel neurogenic niche in the OB. [source] ADVICE OF THE ROSE: EXPERIMENTAL COEVOLUTION OF A TREMATODE PARASITE AND ITS SNAIL HOSTEVOLUTION, Issue 1 2007Britt Koskella Understanding host-parasite coevolution requires multigenerational studies in which changes in both parasite infectivity and host susceptibility are monitored. We conducted a coevolution experiment that examined six generations of interaction between a freshwater snail (Potamopyrgus antipodarum) and one of its common parasites (the sterilizing trematode, Microphallus sp.). In one treatment (recycled), the parasite was reintroduced into the same population of host snails. In the second treatment (lagged), the host snails received parasites from the recycled treatment, but the addition of these parasites did not begin until the second generation. Hence any parasite-mediated genetic changes of the host in the lagged treatment were expected to be one generation behind those in the recycled treatment. The lagged treatment thus allowed us to test for time lags in parasite adaptation, as predicted by the Red Queen model of host,parasite coevolution. Finally, in the third treatment (control), parasites were not added. The results showed that parasites from the recycled treatment were significantly more infective to snails from the lagged treatment than from the recycled treatment. In addition, the hosts from the recycled treatment diverged from the control hosts with regard to their susceptibility to parasites collected from the field. Taken together, the results are consistent with time lagged, frequency-dependent selection and rapid coevolution between hosts and parasites. [source] EXPERIMENTAL EVIDENCE FOR MULTIVARIATE STABILIZING SEXUAL SELECTIONEVOLUTION, Issue 4 2005Robert Brooks Abstract Stabilizing selection is a fundamental concept in evolutionary biology. In the presence of a single intermediate optimum phenotype (fitness peak) on the fitness surface, stabilizing selection should cause the population to evolve toward such a peak. This prediction has seldom been tested, particularly for suites of correlated traits. The lack of tests for an evolutionary match between population means and adaptive peaks may be due, at least in part, to problems associated with empirically detecting multivariate stabilizing selection and with testing whether population means are at the peak of multivariate fitness surfaces. Here we show how canonical analysis of the fitness surface, combined with the estimation of confidence regions for stationary points on quadratic response surfaces, may be used to define multivariate stabilizing selection on a suite of traits and to establish whether natural populations reside on the multivariate peak. We manufactured artificial advertisement calls of the male cricket Teleogryllus commodus and played them back to females in laboratory phonotaxis trials to estimate the linear and nonlinear sexual selection that female phonotactic choice imposes on male call structure. Significant nonlinear selection on the major axes of the fitness surface was convex in nature and displayed an intermediate optimum, indicating multivariate stabilizing selection. The mean phenotypes of four independent samples of males, from the same population as the females used in phonotaxis trials, were within the 95% confidence region for the fitness peak. These experiments indicate that stabilizing sexual selection may play an important role in the evolution of male call properties in natural populations of T. commodus. [source] A FORMAL ASSESSMENT OF GENE FLOW AND SELECTION IN THE FIRE ANT SOLENOPSIS INVICTAEVOLUTION, Issue 2 2000Michael A. D. Goodisman Abstract., Recent studies of the introduced fire ant Solenopsis invicta suggest that introduced polygyne (with multiple queens per nest) populations are strongly influenced by male-mediated gene flow from neighboring monogyne (single queen per nest) populations and selection acting on a single locus, general protein-9 (Gp-9). This investigation formally tests this hypothesis and determines if these processes can account for the genotypic structure of polygyne S. invicta. To increase the statistical power of this test, we considered the genotypes of polygyne queens and workers at both Gp-9 and the closely linked, selectively neutral locus Pgm-3. We then constructed and analyzed a novel mathematical model to delimit the effects of monogyne male gene flow and selection on the joint genotypes at the Pgm-3/Gp-9 superlocus. Using this framework, a hierarchical maximum-likelihood method was developed to estimate the best-fitting gene flow and selection parameters based on the fit of our model to data from both the current study and an earlier one of the same population. In each case, selection on polygyne queens and workers alone, with no monogyne male gene flow, provides the most parsimonious explanation for the observed genotype frequencies. The apparent discrepancy between this result and the empirical evidence for monogyne male gene flow indicates that undocumented factors, such as other forms of selection in polygyne males or workers, are operating in introduced polygyne S. invicta. [source] Effects of defoliation on male and female reproductive traits of a perennial orchid, Dactylorhiza maculataFUNCTIONAL ECOLOGY, Issue 6 2000Vallius E. Abstract 1The effects of defoliation on male reproductive traits of plants have received little attention. We conducted two field experiments with Dactylorhiza maculata (L.) Soó to examine the effects of defoliation on both male and female reproductive traits. We removed 0, 50 or 100% of leaves prior to flowering. The quality of pollen was tested by transferring pollen from the differently treated plants to untreated plants of the same population. 2The non-defoliated plants did not differ from the defoliated plants in mass of pollinia. No differences were found in the weight of seed capsules or in the proportion of embryonic seeds raised by flowers receiving pollen from differently treated pollen donors. 3The non-defoliated and partially defoliated plants produced relatively more and heavier capsules than the completely defoliated plants. 4Defoliation decreased leaf area, corm mass and the probability of flowering in the following year. 5These results demonstrate that defoliation has no acute effects on male traits in the long-living perennial orchid D. maculata. In this respect, D. maculata differs from the two other polycarpic species studied so far. Availability of resources appeared to be insufficient to prevent negative effects of defoliation on the later-occurring and more costly female functions. [source] Resident and transient dynamics, site fidelity and survival in wintering Blackcaps Sylvia atricapilla: evidence from capture,recapture analysesIBIS, Issue 2 2007EDUARDO J. BELDA In their winter quarters, migrant birds may either remain within a small area (resident strategy) or move frequently over a large area looking for locally abundant food (transient strategy). It has been suggested that both strategies could simultaneously occur in the same population. We used time-since-marking capture,recapture models to infer the coexistence of these two behavioural strategies (transient and resident) among wintering Blackcaps Sylvia atricapilla using weekly recapture data over a 7-year period. A related question is whether Blackcaps, if surviving to the next winter, always return to the same wintering area, so we also used this approach to analyse winter site fidelity and to estimate annual survival probabilities. Model selection supported the existence of heterogeneity in survival estimates for both the within-season and the interannual survival probabilities, i.e. there was evidence for the existence of transients. It was estimated that 26% of the Blackcaps were resident during the winter. Mean apparent annual survival probability was 0.46 (se = ±0.11). However, there was some evidence suggesting that not all individuals showed winter site fidelity. The estimated proportion of individuals that, if alive, returned to the wintering area was 28%. This is the first study to show the existence of these two behavioural strategies (residence and transience) among wintering Blackcaps, and the first confirming this pattern using capture,recapture models. These models considering transient and resident dynamics may become an important tool with which to analyse wintering strategies. [source] Perceived oral health: changes over 5 years in one Swedish age-cohortINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 3 2004K Ståhlnacke Objective:,The purpose of this study was to investigate if a change in the social gradients in perceived oral health occurred over a 5-year period, 1992,1997, using a cohort population from two Swedish counties.Methods:,In 1992, a cross-sectional mail questionnaire was sent to all 50-year-old persons in two counties in Sweden, Örebro and Östergötland, and altogether there were 8888 persons. In 1997, the same population was sent a new questionnaire. The cohort, comprising the same respondents from 1992 and 1997, was of 5363 persons. An index of perceived oral health was constructed out of three questionnaire variables: satisfaction with teeth, chewing ability and the number of remaining teeth. This index value was set as a dependent variable in a regression model. Reports of toothache were investigated in a separate logistic regression model.Results:,There were obvious social gradients in the perceived oral health index both in 1992 and in 1997. Marital status, foreign birth, education and occupation were all substantially related to the perceived oral health. The change in perceived oral health was analysed. Almost half of the cohort (47.4%) showed no change at all. Those with increased and those with decreased health were rather evenly distributed on both sides, with 22.0% with better health in 1997 and 30.6% with worse health. Gender and education were related to toothache experience. Conclusion: Changes have been moderate in the perceived oral health in this cohort, despite the rather drastic changes in the remuneration of dental care during this study time. However, this also means that the social differences remain, despite the official goals of increased equity. [source] A phenomenological study of ripening of salted herring.JOURNAL OF CHEMOMETRICS, Issue 2 2002Assessing homogeneity of data from different countries, laboratories Abstract Data from ripening experiments of herring carried out at three Nordic fishery research institutions in the period 1992,1995 were collected and analyzed by multivariate analysis. The experiments were carried out at different times, with different stocks as raw material, using different types of treatments and analyzed in different laboratories. The question considered here is whether these data can be assumed to be one homogeneous set of data pertaining to ripening of salted herring or whether data from different labs, stocks, etc. must be considered independently. This is of importance for further research into ripening processes with these and similar data. It is shown in this paper that all data can be considered as one homogeneous data set. This is verified using resampling where latent structures are compared between different sample sets. This is done indirectly by testing regression models, that have been developed on one sample set, on other sample sets. It is also done directly by monitoring the deviation in latent structure observed between different sample sets. No formal statistical test is developed for whether samples can be assumed to stem from the same population. Although this can easily be envisioned, it was exactly the need for a more intuitive and visual test that prompted this work, developing different exploration tools that visually make it clear how well the data can be assumed to derive from the same population. Subsequently analyzing the data as one homogeneous group provides new information about factors that govern the ripening of salted herring and can be used in new strategic research as well as in industrial practice. Copyright © 2002 John Wiley & Sons, Ltd. [source] The effect of periodontal treatment on glycemic control in patients with type 2 diabetes mellitusJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2001James E. Stewart Abstract Background, aims: This study was designed to explore the effect of periodontal therapy on glycemic control in persons with type 2 diabetes mellitus (DM). Methods: 36 patients with type 2 DM (treatment group) received therapy for adult periodontitis during an 18-month period. A 36-person control group was randomly selected from the same population of persons with type 2 DM who did not receive periodontal treatment. Results: These groups were well matched for most of the parameters investigated. During the nine-month observation period, there was a 6.7% improvement in glycemic control in the control group when compared to a 17.1% improvement in the treatment group, a statistically significant difference. Several parameters that could confound or moderate this glycemic control were explored. These included the treatment of non-dental infections, weight and medication changes. No moderating effect was associated with any of these variables. However, there were too few subjects in the study to have the statistical power necessary to assess these possible moderators of glycemic control. Conclusions: We interpret the data in the study to suggest that periodontal therapy was associated with improved glycemic control in persons with type 2 DM. Zusammenfassung Zielsetzung: Untersuchung der Wirkung parodontaler Therapie auf die Blutzuckerkontrolle bei Patienten mit Typ-2-Diabetes mellitus (DM2). Material und Methoden: 260 Patienten, die am Veteranenhospital in Los Angeles ambulant wegen Diabetes mellitus betreut wurden, wurde eine zahnmedizinische Behandlung empfohlen und angeboten. Von den 92 DM2-Patienten, die dieses Angebot wahrnahmen, wurden 36 Patienten, die an Erwachsenenparodontitis litten, parodontal behandelt: Wurzelglättung, subgingivale Kürettage, Extraktionen (Testgruppe). Von den DM2-Patienten, die keine Parodontalbehandlung durchführen ließen, wurde eine Kontrollgruppe mit 36 Personen gebildet. Die Blutzuckerkontrolle wurde in der Testgruppe vor Therapie und 10 Monate später über den arameter Hämoglobin A1C (HbA1C) bestimmt. In der Kontrollgruppe lagen 8,10 Monate zwischen den HbA1C -Untersuchungszeitpunkten. Ergebnisse: Beide Gruppen entsprachen einander sehr gut für die meisten untersuchten Parameter. Während der Beobachtungszeit von 9 Monaten verbesserte sich die Blutzuckerkontrolle in der Kontrolgruppe um 6.7% und in der Testgruppe um 17.1% (p=0.02). Verschiedene Parameter, die die Kontrolle des Blutzuckerspiegels beeinflussen könnten, wurden untersucht (z.B. nicht-dentale Infektionen, Veränderungen des Körpergewichtes oder der Medikation). Es konnte kein Einfluß dieser Faktoren gefunden werden. Allerdings ist die Stichprobe zu klein, um diese Aussage mit genügender Teststärke treffen zu können. Schlußfolgerungen: Parodontale Therapie der Erwachsenenparodontitis ist mit einer verbesserten Blutzuckerkontrolle bei DM2-Patienten assoziiert. Résumé Cette étude a été réalisée pour examiner les effets du traitement parodontal chez des personnes atteintes de diabète mellitus type 2 (DM). 36 patients atteints de DM type 2 (groupe traitement) furent traités pour une partodontite de l'adulte pendant une période de 18 mois. Un groupe contrôle de 36 personnes fut sélectionnê au hasard à partir de la même population (DM) mais sans recevoir de traitement parodontal. Ces groupes furent comparés entre eux pour la plupart des paramètres examinés. Pendant la période d'observation de 9 mois, il y avait une amélioration de 6.7% du controle de la glycémie dans le groupe contrôle comparéà une amélioration de 17.1% pour le groupe traité, cette différence étant statistiquement significative. Plusieurs paramètres comme le traitement d'infections non dentaires et les changements de poids et de prescription, qui auraient pu moduler le controle de la glycémie ont été explorés. Aucun effect de modulation ne put être associé avec aucune de ces variables. Cependant, il y avait trop peu de sujets inclus dans l'étude pour permettre un pouvoir statistique nécessaire pour préciser ces possibles modulateurs du contróle de la glycémie. Nous interprétons les données de l'étude pour suggérer que le traitement paradontal est associéà une amélioration de la glycémie chez les personnes atteintes de diabéte mellitus type 2. [source] Reduced reproductive success and offspring survival in fragmented populations of the forest herb Phyteuma spicatumJOURNAL OF ECOLOGY, Issue 6 2005ANNETTE KOLB Summary 1Habitat fragmentation, which reduces the size and increases the isolation of populations, is a major threat to biodiversity. For Phyteuma spicatum, a self-incompatible, rare understorey herb in deciduous forests of north-western Germany, I tested the hypotheses that: (i) fitness (in terms of reproductive success) is reduced in small or isolated populations, (ii) reproduction in small populations is reduced by pollen limitation and (iii) genetic effects cause fitness reductions in small populations. 2I compared the reproductive success of plants of Phyteuma in 14 populations of different size and degree of isolation. Seed production was, as predicted, positively related to population size but was also influenced by plant size, although not by population isolation, density or habitat quality. 3I performed supplemental hand-pollinations in 10 of the 14 populations using pollen from the same population (test for pollen quantity) or from another large population (pollen quality). The proportional difference in seed production between hand-pollinated plants and open-pollinated controls increased with decreasing population size, indicating pollinator limitation of reproduction in small populations. There was no difference between the two hand-pollination treatments, suggesting that a sufficient number of cross-compatible mates was available even in the smallest populations. 4Progeny from the 14 populations were grown for 32 weeks in a common environment. There was no effect of population size on germination, but final seedling survival was positively related to population size, and this relationship was more pronounced in the glasshouse than under more favourable growing conditions in a common garden. Genetic effects may thus reduce fitness (here measured in terms of survival) in plants from small populations, making them more susceptible to environmental stress. 5The results suggest that both reproduction and offspring performance may be reduced in small populations even of long-lived species such as Phyteuma spicatum. Different processes, such as pollen limitation and genetic deterioration, may interact and affect local population dynamics and the persistence of species in fragmented landscapes. [source] Description of a new Lake Tanganyikan cichlid fish of the genus Cyprichromis(Perciformes: Cichlidae) with a note on sexual dimorphismJOURNAL OF FISH BIOLOGY, Issue SB 2006T. Takahashi Cyprichromis coloratus, a new cichlid species, is described based on 41 type specimens from the Zambian coast of Lake Tanganyika. It differs from Cyprichromis microlepidotus by having fewer scales in the longitudinal line (41,44 v. 59,70 in C. microlepidotus) and upper lateral line (31,36 v. 47,59), from Cyprichromis leptosoma by more dorsal-fin spines (14,15 v. 11,13 in C. leptosoma) and longitudinal line scales (41,44 v. 38,40), from Cyprichromis pavo by fewer dorsal-fin spines and soft rays (29,31, usually 30, in total v. 30,32, usually 31, in C. pavo), and from Cyprichromis zonatus by shallower body depth [24·0,28·5 (26·4 ± 1·1)% of standard length v. 24·5,30·5 (28·4 ± 1·3)% in C. zonatus] and smaller eye [eye length 25·2,30·9 (27·2 ± 1·1)% of head length v. 27·9,33·3 (30·2 ± 1·2)%]. The new species is also separable from C. microlepidotus, C. pavo and C. zonatus by absence of distinct small spots on the body (v. pearl grey and yellowish small spots along scale rows on body at least in males of C. microlepidotus and C. pavo), its distinct dichromatism (particularly on the caudal fin) between males of the same population (v. dichromatism absent in C. zonatus) and absence of vertical bands (v. three or four distinct vertical bands beneath dorsal fin base in live males of C. zonatus). Cyprichromis coloratus n. sp. also exhibits sexual dimorphism, females having a larger head and males having longer pelvic fin, differences which are discussed in relation to reproductive behaviour. A key to the five species of Cyprichromis is included. A lectotype is designated for Cyprichromis leptosoma. [source] Application of in situ detection techniques to determine the systemic condition of lymphocystis disease virus infection in cultured gilt-head seabream, Sparus aurata L.JOURNAL OF FISH DISEASES, Issue 2 2009I Cano Abstract Immunohistochemistry (IHC) and in situ hybridization (ISH) techniques have been used for the detection of lymphocystis disease virus (LCDV) in formalin-fixed, paraffin-embedded tissues from gilt-head seabream, Sparus aurata L. Diseased and recovered fish from the same population were analysed. IHC was performed with a polyclonal antibody against a 60-kDa viral protein. A specific digoxigenin-labelled probe, obtained by PCR amplification of a 270-bp fragment of the gene coding the LCDV major capsid protein, was used for ISH. LCDV was detected in skin dermis and gill lamellae, as well as in several internal organs such as the intestine, liver, spleen and kidney using both techniques. Fibroblasts, hepatocytes and macrophages seem to be target cells for virus replication. The presence of lymphocystis cells in the dermis of the skin and caudal fin, and necrotic changes in the epithelium of proximal renal tubules were the only histological alterations observed in fish showing signs of the disease. [source] The Trophic Effects of Oestrogen on Male Rat Anterior Pituitary LactotrophsJOURNAL OF NEUROENDOCRINOLOGY, Issue 5 2009L. A. Nolan Rapid but often transient changes in mitotic and apoptotic activity are important components of the pituitary response to changes in the hormonal environment. For example, bilateral adrenalectomy and orchidectomy each result in a wave of increased mitosis lasting approximately 1 week, mediated by the same population of trophically active and, to a large extent, endocrinologically inactive cells. By contrast to these tonic inhibitors of pituitary trophic activity, reports of a progressive increase in lactotroph numbers during pregnancy suggest that oestrogen is a potent and persistent pituitary mitogen. By comparing the amplitude and duration of male rat anterior pituitary mitotic responses to oestrogen treatment, to adrenalectomy, and to a combination of the two, the present study aimed to further clarify the characteristics of the oestrogen-induced trophic response, in particular whether lactotrophs are the predominant cell type involved. Adrenalectomy produced a wave of increased mitotic activity, which resolved within 7 days as expected, whereas oestrogen induced a significant increase in mitotic activity, which was sustained for the 14-day duration of the study. The trophic effects of combining adrenalectomy and oestrogen treatment were not additive in that the statistically insignificant upward trend in mitotic index during the first few days compared to oestrogen treatment alone was entirely abolished by oestrogen pre-treatment. The increase in mitotic activity in lactotrophs induced by oestrogen either with or without adrenalectomy did not result in an increase in the relative size of the prolactin-positive compared to prolactin-negative pituitary parenchymal cell numbers by the end of the study. Despite the marked increase in the lactotroph population that is reported during pregnancy, these data indicate that at least the early (i.e. within 2 weeks) mitotic response to pharmacological doses of oestrogen increases mitotic activity in the lactotroph subpopulation by only 5,8% relative to other cellular subpopulations. Unexpectedly, the mitotic response to oestrogen principally occurs in non-prolactin-containing cells and results in the recruitment, amongst other trophically responsive populations, of the entire subpopulation of prolactin-, adrenocorticotrophic hormone- and luteinising hormone-negative cells that respond mitotically to adrenalectomy. Oestrogen therefore has a previously unrecognised non-cell type-specific trophic effect in the pituitary that obscures the relative expansion of the lactotroph population by inducing concurrent increases in numbers of prolactin-negative cells, the nature of which at least in part remains to be determined. [source] OOSPORE VARIATION IN CLOSELY RELATED CHARA TAXA,JOURNAL OF PHYCOLOGY, Issue 5 2009Maja Blume Charophytes produce a thick-walled zygote, the so-called oospore, the characters of which (size, shape, and structure) are used as taxonomic determination criteria. In the present study, the variation of length, width, length-to-width ratio, and number of striae of oospores collected both from the field and after cross-fertilization experiments was compared within and among taxa, populations, and individuals belonging to the Chara baltica Bruzelius "species complex." Although the oospore characteristics differed significantly among the taxa, the variations among populations belonging to the same taxon and even among individuals belonging to the same population were still higher. Oospores developed by means of allogamy were not significantly different from oospores developed by autogamy. Oospores were 5% shorter and 27% narrower when measured dry compared with wet material. Information about this treatment is unfortunately lacking in charophyte monographs and oospore determination keys. We concluded that oospore descriptions of different charophyte taxa should be based on a larger amount of data material collected from different populations and individuals and accompanied by a detailed method description, and that a determination of closely related taxa by means of oospores should be interpreted carefully. Ecological aspects of oospore size variation are discussed. [source] Factors Associated with Outcome in Foals with Neonatal Isoerythrolysis (72 Cases, 1988,2003)JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2008A.C. Polkes Background: Neonatal foals with isoerythrolysis (NI) often die, but the risk factors for death have not been identified. Objectives: To identify factors associated with outcome in foals with NI and to identify factors associated with death from liver failure or kernicterus in the same population. Animals: Seventy-two foals with NI examined at referral institutions. Methods: Retrospective case series. Information on signalment, clinical examination findings, laboratory testing, treatment, complications, outcome, and necropsy results were obtained. Results: The overall survival rate was 75% (54 of 72). Liver failure (n = 7), kernicterus (n = 6), and complications related to bacterial sepsis (n = 3) were the 3 most common reasons for death or euthanasia. The number of transfusions with blood products was the factor most strongly associated with nonsurvival in a multivariate logistic regression model. The odds of liver failure developing in foals receiving a total volume of blood products , 4.0 L were 19.5 (95% confidence intervals [CI]: 2.13,178) times higher than that of foals receiving a lower volume (P= .009). The odds of kernicterus developing in foals with a total bilirubin , 27.0 mg/dL were 17.0 (95% CI: 1.77,165) times higher than that of foals with a lower total bilirubin (P= .014). Conclusions and Clinical Importance: Development of liver failure, kernicterus, and complications related to bacterial sepsis are the most common causes of death in foals with NI. Foals administered a large volume of blood products are at greater risk for developing liver failure. [source] Intensity-based signal separation algorithm for accurate quantification of clustered centrosomes in tissue sectionsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 12 2006Markus C. Fleisch Abstract Centrosomes are small organelles that organize the mitotic spindle during cell division and are also involved in cell shape and polarity. Within epithelial tumors, such as breast cancer, and some hematological tumors, centrosome abnormalities (CAs) are common, occur early in disease etiology, and correlate with chromosomal instability and disease stage. In situ quantification of CA by optical microscopy is hampered by overlap and clustering of these organelles, which appear as focal structures. CA has been frequently associated with Tp53 status in premalignant lesions and tumors. Here the authors described an approach to accurately quantify centrosome frequencies in tissue sections and tumors, independently of background or noise levels. Applying simple optical rules in nondeconvolved conventional 3D images of stained tissue sections, the authors showed that they could evaluate more accurately and rapidly centrosome frequencies than with traditional investigator-based visual analysis or threshold-based techniques. The resulting population-based frequency of centrosomes per nucleus could then be used to approximate the proportion of cells with CA in that same population. This was done by taking into account baseline centrosome amplification and proliferation rates measured in the tissue. Using this technique, the authors showed that 20,30% of cells have amplified centrosomes in Tp53 null mammary tumors. Microsc. Res. Tech., 2006. © 2006 Wiley-Liss, Inc. [source] Genetics, behaviour and chemical recognition of the invading ant Pheidole megacephalaMOLECULAR ECOLOGY, Issue 2 2009DENIS FOURNIER Abstract Introduced species often become ecologically dominant, displacing native species and posing a serious threat to ecosystem function and global biodiversity. Ants are among the most widespread and damaging alien species; introductions are often accompanied by population-level behavioural and genetic changes contributing to their success. We investigated the genetic structure, chemical profile and nestmate recognition in introduced populations of the invasive big-headed ant, Pheidole megacephala, in Australia. Behavioural analyses show that workers are not aggressive towards conspecifics from different nests, even at large geographical scales (up to 3000 km) and between populations encompassing a wide range of environmental conditions. By contrast, interactions with workers of other species invariably result in agonistic behaviours. Genetic analyses reveal that populations have low genetic diversity. No genetic differentiation occurs among nests of the same population; differentiation between populations, though significant, remains weak. Chemical analyses indicate that cuticular lipids are similar between colonies of a population, and that differentiation between populations is low. Altogether, these results indicate that the big-headed ant P. megacephala forms a large unicolonial population across northern/eastern Australia. [source] A phylogeographical study of the Turnip mosaic virus population in East Asia reveals an ,emergent' lineage in JapanMOLECULAR ECOLOGY, Issue 14 2006YASUHIRO TOMITAKA Abstract The genetic structure of populations of Turnip mosaic virus (TuMV) in East Asia was assessed by making host range and gene sequence comparisons of 118 isolates utilizing a population genetic approach. Most, but not all, isolates collected from Brassica plants in China infected only Brassica plants, whereas those from Japan infected both Brassica and Raphanus (BR) plants. Analyses of the positions of recombination sites in five regions of the genomes (one third of the full sequence) of the many recombinant isolates were fully congruent with the results of phylogenetic analysis, and at least one recombination type pattern was shared between Chinese and Japanese populations. One lineage of nonrecombinant isolates from the basal-BR lineage was found in 2000 in Kyushu, Japan but none in China, and have since been found over the whole island. The sudden expansion of this basal-BR population was strongly supported by calculations showing the deviations from the neutral equilibrium model for the individual geographical lineages with overall lack of nucleotide diversity, and by analysis of mismatch distribution. Our study shows that the recent Chinese and Japanese TuMV isolates are part of the same population but are discrete lineages. [source] SNPs in ecological and conservation studies: a test in the Scandinavian wolf populationMOLECULAR ECOLOGY, Issue 2 2005J. M. SEDDON Abstract Single nucleotide polymorphisms (SNPs) have the potential to become the genetic marker of choice in studies of the ecology and conservation of natural populations because of their capacity to access variability across the genome. In this study, we provide one of the first demonstrations of SNP discovery in a wild population in order to address typical issues of importance in ecology and conservation in the recolonized Scandinavian and neighbouring Finnish wolf Canis lupus populations. Using end sequence from BAC (bacterial artificial chromosome) clones specific for dogs, we designed assays for 24 SNP loci, 20 sites of which had previously been shown to be polymorphic in domestic dogs and four sites were newly identified as polymorphic in wolves. Of the 24 assayed loci, 22 SNPs were found to be variable within the Scandinavian population and, importantly, these were able to distinguish individual wolves from one another (unbiased probability of identity of 4.33 × 10,8), providing equivalent results to that derived from 12 variable microsatellites genotyped in the same population. An assignment test shows differentiation between the Scandinavian and neighbouring Finnish wolf populations, although not all known immigrants are accurately identified. An exploration of the misclassification rates in the identification of relationships shows that neither 22 SNP nor 20 microsatellite loci are able to discriminate across single order relationships. Despite the remaining obstacle of SNP discovery in nonmodel organisms, the use of SNPs in ecological and conservation studies is encouraged by the advent of large scale screening methods. Furthermore, the ability to amplify extremely small fragments makes SNPs of particular use for population monitoring, where faecal and other noninvasive samples are routinely used. [source] Movement patterns and study area boundaries: influences on survival estimation in capture,mark,recapture studiesOIKOS, Issue 8 2008Gregg E. Horton The inability to account for the availability of individuals in the study area during capture,mark,recapture (CMR) studies and the resultant confounding of parameter estimates can make correct interpretation of CMR model parameter estimates difficult. Although important advances based on the Cormack,Jolly,Seber (CJS) model have resulted in estimators of true survival that work by unconfounding either death or recapture probability from availability for capture in the study area, these methods rely on the researcher's ability to select a method that is correctly matched to emigration patterns in the population. If incorrect assumptions regarding site fidelity (non-movement) are made, it may be difficult or impossible as well as costly to change the study design once the incorrect assumption is discovered. Subtleties in characteristics of movement (e.g. life history-dependent emigration, nomads vs territory holders) can lead to mixtures in the probability of being available for capture among members of the same population. The result of these mixtures may be only a partial unconfounding of emigration from other CMR model parameters. Biologically-based differences in individual movement can combine with constraints on study design to further complicate the problem. Because of the intricacies of movement and its interaction with other parameters in CMR models, quantification of and solutions to these problems are needed. Based on our work with stream-dwelling populations of Atlantic salmon Salmo salar, we used a simulation approach to evaluate existing CMR models under various mixtures of movement probabilities. The Barker joint data model provided unbiased estimates of true survival under all conditions tested. The CJS and robust design models provided similarly unbiased estimates of true survival but only when emigration information could be incorporated directly into individual encounter histories. For the robust design model, Markovian emigration (future availability for capture depends on an individual's current location) was a difficult emigration pattern to detect unless survival and especially recapture probability were high. Additionally, when local movement was high relative to study area boundaries and movement became more diffuse (e.g. a random walk), local movement and permanent emigration were difficult to distinguish and had consequences for correctly interpreting the survival parameter being estimated (apparent survival vs true survival). [source] Congenital toxoplasmosis: late pregnancy infections detected by neonatal screening and maternal serological testing at deliveryPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 6 2007Eleonor G. Lago Summary The first aim of this study was to determine the prevalence of congenital toxoplasmosis in newborn infants treated by the public health system in Porto Alegre, a city in southern Brazil, using neonatal screening for Toxoplasma gondii -specific IgM. The second aim was to investigate whether the cases detected by this approach could have been identified by the prenatal screening for antibodies to T. gondii that was performed in the same population. A fluorometric assay was used to analyse T. gondii -specific IgM in filter paper specimens obtained from newborn infants for routine screening for metabolic diseases. When the specific IgM was positive, serum samples from the infant and the mother were requested for confirmatory serological testing, and the infant underwent clinical examination. Among 10 000 infants screened for T. gondii -specific IgM, seven filter paper samples were positive, and congenital toxoplasmosis was confirmed in six patients. The prevalence of IgM specific for T. gondii was 6/10 000 [95% CI 2/10 000, 13/10 000]. One infected infant had already been identified in the maternity ward before birth, three had been identified by maternal serology at delivery, and two infants with congenital toxoplasmosis were identified solely through neonatal screening. Although four mothers of the patients with congenital toxoplasmosis received prenatal care, and three mothers had one or two serological tests for T. gondii -specific antibodies (one at first trimester, one at first and second trimesters, and the other at second and third trimesters), they were not identified during pregnancy as infected. Neonatal screening identified cases of infection not detected by obtaining only one or two serum samples from pregnant women for T. gondii serology, mainly when infection was acquired and transmitted in late pregnancy. Maternal serology at delivery and neonatal screening were especially useful in the identification of infants with congenital toxoplasmosis when the mother did not receive regular prenatal serological testing or prenatal care. [source] Artificial neural networks as statistical tools in epidemiological studies: analysis of risk factors for early infant wheezePAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 6 2004Andrea Sherriff Summary Artificial neural networks (ANNs) are being used increasingly for the prediction of clinical outcomes and classification of disease phenotypes. A lack of understanding of the statistical principles underlying ANNs has led to widespread misuse of these tools in the biomedical arena. In this paper, the authors compare the performance of ANNs with that of conventional linear logistic regression models in an epidemiological study of infant wheeze. Data on the putative risk factors for infant wheeze have been obtained from a sample of 7318 infants taking part in the Avon Longitudinal Study of Parents and Children (ALSPAC). The data were analysed using logistic regression models and ANNs, and performance based on misclassification rates of a validation data set were compared. Misclassification rates in the training data set decreased as the complexity of the ANN increased: h = 0: 17.9%; h = 2: 16.2%; h = 5: 14.9%, and h = 10: 9.2%. However, the more complex models did not generalise well to new data sets drawn from the same population: validation data set misclassification rates: h = 0: 17.9%; h = 2: 19.6%; h = 5: 20.2% and h = 10: 22.9%. There is no evidence from this study that ANNs outperform conventional methods of analysing epidemiological data. Increasing the complexity of the models serves only to overfit the model to the data. It is important that a validation or test data set is used to assess the performance of highly complex ANNs to avoid overfitting. [source] | ||||||||||||||||||||||||||||||||||