bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutation at high rates reduces spatial structure within populations
Authors: EPPERSON BRYAN K. 
Published: February 2005

AbstractThe question of whether or not the high rates (µ) of mutation that occur for some hypervariable markers can affect commonly used empirical measures of spatial structure of genetic variation within populations is addressed. The results show that values of these measures are approximately halved when µ is 10−2. Finest spatial‐scale correlations, measured by either Moran's I‐statistics or conditional kinship, are reduced by 30%−50%. When the mutation rate is 10 times lower, much smaller reductions result, e.g. averaging 7% for the finest scale correlations. Still smaller orders of magnitude of µ cause negligible changes in spatial structure, where any effects normally would not be detectable. The reductions are caused by forward mutations, and when the reductions are measured as percentages, they are nearly independent of the amount of structure produced sans mutation, except when dispersal is nearly minimal. The percent reductions are also nearly independent of the number of alleles and of back mutations, hence of the nature of the mutation process (e.g. stepwise or not). The results demonstrate that some hypervariable loci should have reduced spatial structuring, and that marker choice may affect the values observed in experimental surveys. Moreover, if fine‐scale correlations are used to indirectly estimate dispersal distances, then mutation at high rates could inflate estimates, easily up to two‐ to three‐fold.
INVITED REVIEW: Using genome scans of DNA polymorphism to infer adaptive population divergence
Authors: STORZ JAY F. 
Published: February 2005

AbstractElucidating the genetic basis of adaptive population divergence is a goal of central importance in evolutionary biology. In principle, it should be possible to identify chromosomal regions involved in adaptive divergence by screening genome‐wide patterns of DNA polymorphism to detect the locus‐specific signature of positive directional selection. In the case of spatially separated populations that inhabit different environments or sympatric populations that exploit different ecological niches, it is possible to identify loci that underlie divergently selected traits by comparing relative levels of differentiation among large numbers of unlinked markers. In this review I first address the question of whether diversifying selection on polygenic traits can be expected to produce predictable patterns of allelic variation at the underlying quantitative trait loci (QTL), and whether the locus‐specific effects of selection can be reliably detected against the genome‐wide backdrop of stochastic variability. I then review different approaches that have been developed to identify loci involved in adaptive population divergence and I discuss the relative merits of model‐based approaches that rely on assumptions about population structure vs. model‐free approaches that are based on empirical distributions of summary statistics. Finally, I consider the evolutionary and functional insights that might be gained by conducting genome scans for loci involved in adaptive population divergence.
An insight into the genetic variation of Schistosoma japonicum in mainland China using DNA microsatellite markers
Authors: SHRIVASTAVA JAYA , QIAN BAO ZHEN , MCVEAN GILEAN , WEBSTER JOANNE P. 
Published: February 2005

AbstractThis study presents the first microsatellite investigation into the level of genetic variation among Schistosoma japonicum from different geographical origins. S. japonicum isolates were obtained from seven endemic provinces across mainland China: Zhejiang (Jiashan County), Anhui (Guichi County), Jiangxi (Yongxiu County), Hubei (Wuhan County), Hunan (Yueyang area), Sichuan 1 (Maoshan County), Sichuan 2 (Tianquan County), Yunnan (Dali County), and also one province in the Philippines (Sorsogon). DNA from 20 individuals from each origin were screened against 11 recently isolated and characterized S. japonicum microsatellites, and a set of nine loci were selected based on their polymorphic information content. High levels of polymorphism were obtained between and within population samples, with Chinese and Philippine strains appearing to follow different lineages, and with distinct branching between provinces. Moreover, across mainland China, genotype clustering appeared to be related to habitat type and/or intermediate host morph. These results highlight the suitability of microsatellites for population genetic studies of S. japonicum and suggest that there may be different strains of S. japonicum circulating in mainland China.
The latitudinal cline in the In(3R)Payne inversion polymorphism has shifted in the last 20 years in Australian Drosophila melanogaster populations
Authors: ANDERSON ALISHA R. , HOFFMANN ARY A. , MCKECHNIE STEPHEN W. , UMINA PAUL A. , WEEKS ANDREW R. 
Published: February 2005

AbstractClinal variation has been described in a number of inversions in Drosophila but these clines are often characterized by cytological techniques using small sample sizes, and associations with specific genes are rarely considered. Here we have developed a molecular assay for In(3R)Payne in Drosophila melanogaster from eastern Australia populations. It shows in repeated samples that the inversion cline is very tightly associated with latitude and is almost fixed in tropical populations while relatively rare in temperate populations. This steep cline has shifted in position in the last 20 years. The heat shock gene, hsr‐omega, located centrally inside the inversion sequence, shows a different clinal pattern to In(3R)Payne. These results suggest strong ongoing selection on In(3R)Payne over the last 100 years since the colonization of Australia that is partly independent of hsr‐omega.
Population genetic structure of annual and perennial populations ofZostera marinaL. along the Pacific coast of Baja California and the Gulf of California
Authors: MUÑIZ‐SALAZAR RAQUEL , TALBOT SANDRA L. , SAGE GEORGE K. , WARD DAVID H. , CABELLO‐PASINI ALEJANDRO 
Published: February 2005

AbstractThe Baja California peninsula represents a biogeographical boundary contributing to regional differentiation among populations of marine animals. We investigated the genetic characteristics of perennial and annual populations of the marine angiosperm,Zostera marina,along the Pacific coast of Baja California and in the Gulf of California, respectively. Populations ofZ.marinafrom five coastal lagoons along the Pacific coast and four sites in the Gulf of California were studied using nine microsatellite loci. Analyses of variance revealed significant interregional differentiation, but no subregional differentiation. Significant spatial differentiation, assessed using θSTvalues, was observed among all populations within the two regions.Z. marinapopulations along the Pacific coast are separated by more than 220 km and had the greatest θST(0.13–0.28) values, suggesting restricted gene flow. In contrast, lower but still significant genetic differentiation was observed among populations within the Gulf of California (θST = 0.04–0.18), even though populations are separated by more than 250 km. This suggests higher levels of gene flow among Gulf of California populations relative to Pacific coast populations. Direction of gene flow was predominantly southward among Pacific coast populations, whereas no dominant polarity in the Gulf of California populations was observed. The test for isolation by distance (IBD) showed a significant correlation between genetic and geographical distances in Gulf of California populations, but not in Pacific coast populations, perhaps because of shifts in currents during El Niño Southern Oscillation (ENSO) events along the Pacific coast.
Hyperdiversity of ectomycorrhizal fungus assemblages on oak seedlings in mixed forests in the southern Appalachian Mountains
Authors: WALKER JOHN F. , K. MILLER ORSON , HORTON JONATHAN L. 
Published: February 2005

AbstractDiversity of ectotrophic mycobionts on outplanted seedlings of two oak species (Quercus rubra and Quercus prinus) was estimated at two sites in mature mixed forests in the southern Appalachian Mountains by sequencing nuclear 5.8S rRNA genes and the flanking internal transcribed spacer regions I and II (ITS). The seedlings captured a high diversity of mycorrhizal ITS‐types and late‐stage fungi were well represented. Total richness was 75 types, with 42 types having a frequency of only one. The first and second order jackknife estimates were 116 and 143 types, respectively. Among Basidiomycetes, tomentelloid/thelephoroid, russuloid, and cortinarioid groups were the richest. The ascomycete Cenococcum geophilum was ubiquitously present. Dominant fungi included a putative Tuber sp. (Ascomycetes), and Basidiomycetes including a putative Craterellus sp., and Laccaria cf. laccata. Diversity was lower at a drier high elevation oak forest site compared to a low elevation mesic cove — hardwood forest site. Fungal specificity for red oak vs. white oak seedlings was unresolved. The high degree of rarity in this system imposes limitations on the power of community analyses at finer scales. The high mycobiont diversity highlights the potential for seedlings to acquire carbon from mycelial networks and confirms the utility of using outplanted seedlings to estimate ectomycorrhizal diversity.
Intradermal testing with the storage miteTyrophagus putrescentiaein normal dogs and dogs with atopic dermatitis in Colorado
Authors: MUELLER RALF S. , FIESELER KATHRYN V. , ROSYCHUK RODNEY A. W. , GREENWALT TRACEY 
Published: February 2005

Abstract The purpose of this study was to evaluate reactions to intradermal injections ofTyrophagus putrescentiaeextract in healthy dogs and dogs with atopic dermatitis and to compare the prevalence of positive reactions in the two groups. Twenty‐one healthy dogs and 26 atopic dogs were tested intradermally withT. putrescentiaeextract at 1000, 500, 250, 125, 63, 32 and 16 PNU/mL. Reactions were evaluated objectively and subjectively. A Mann–Whitney test was used to determine differences in grade of reaction to storage mites between healthy dogs and dogs with atopic dermatitis. Positive reactions to storage mite extract were most common at 1000 PNU/mL with approximately one third of normal and atopic dogs showing a positive reaction toT. putrescentiae.There was no significant difference in the incidence of positive reactions between normal and atopic dogs for any of theTyrophagusextract concentrations.
Calcinosis involving multiple paws in a cat with chronic renal failure and in a cat with hyperthyroidism
Authors: DECLERCQ J. , BHATTI S. 
Published: February 2005

Abstract Calcinosis of multiple paws is described in two cats. A metastatic pathogenesis was supported by the laboratory findings of hyperphosphataemia and a calcium × phosphorus solubility product > 7 g/L. Hyperparathyroidism could not be confirmed because a valid feline parathyroid hormone assay was not available at the time. One cat was diagnosed with chronic renal failure and presented initially with an irregular nodular calcification on the chin. Dietary and medical management was unsuccessful and ultimately the animal was euthanased. Hyperthyroidism was diagnosed in another cat by laboratory findings and scintigraphic imaging. In addition, the cat had a hyperphosphataemia in the absence of azotaemia. Intravenous administration of radioactive iodine as131I was accompanied by reduction and normalization in serum total thyroxine and phosphorus concentrations and resulted in resolution of calcification in the paws.
The biology ofMalasseziaorganisms and their ability to induce immune responses and skin disease
Authors: CHEN TAI‐AN , HILL PETER B. 
Published: February 2005

TABLE OF CONTENTSIntroduction 4History and taxonomy of the genusMalassezia 5Biological characteristics ofMalasseziaorganisms 5Structure 5Reproduction 6Biochemistry 6Distribution ofMalasseziaorganisms on the host 6Immunological and epidermal responses toMalasseziaorganisms 7The immune response toMalasseziaorganisms 7Antigen release, penetration and presentation 8Cell‐mediated immune responses 8IgG, IgM and IgA responses toMalasseziaorganisms 9IgE responses toMalasseziaorganisms 10Mast cell responses 11Epidermal responses associated withMalasseziadermatitis 12Malasseziaorganisms as pathogens in humans and animals 13Diseases associated withMalasseziaspp. in humans 13Pityriasis versicolor 13Malasseziafolliculitis 13Seborrheic dermatitis and dandruff 14Atopic dermatitis 14Malasseziafungaemia 14Diseases associated withMalasseziaspp. in animals 15Malasseziadermatitis in dogs 15Predisposing factors for overgrowth ofMalassezia pachydermatis 15Pathogenesis 16Clinical features 16Diagnosis 17Treatment 18Conclusions 19References 19
Impact of sample storage on detection of periodontal bacteria
Authors: Katsoulis J. , Heitz‐Mayfield L. J. R. , Weibel M. , Hirschi R. , Lang N. P. , Persson G. R. 
Published: February 2005

Background/aims:  Information on the impact of sample storage prior to analysis by DNA methods is limited. The aim of this study was to investigate the effect of subgingival sample storage on bacterial detection and enumeration.Material and methods:  Subgingival plaque samples were studied by a) checkerboard DNA–DNA hybridization by immediate processing, b) storage at + 4°C for 6 weeks, c) storage at − 20°C for 6 months or d) storage at − 20°C for 12 months.Results:  No differences in total DNA were found between protocol 1 and 2, or between protocol 3 and 4. Protocol 1 yielded 2.4 times more total bacterial DNA than did protocol 3 (P < 0.001). Actinobacillus actinomycetemcomitans and Campylobacter gracilis were detected in 21.1% of the immediately processed samples but only in 6.6% of the samples after 12 months of storage. Similar changes were noticed for Treponema denticola, which was detected in 22.3% and 9.2%, respectively. Streptococci spp., Fusobacterium nucleatum and Tannerella forsythia did not seem to be affected by storage. In contrast, the level of Campylobacter rectus detection frequency changed from 2.6% if processed immediately to 15.8% if samples were stored for 12 months.Conclusions:  In longitudinal clinical studies including microbiological samples and processed with DNA–DNA hybridization methods, samples should be stored for the same period of time before processing to avoid loss of microbiological information.
Study of anticandidal activity of carvacrol and eugenol in vitro and in vivo
Authors: Chami N. , Bennis S. , Chami F. , Aboussekhra A. , Remmal A. 
Published: February 2005

Background/aims:  The mechanism of the anticandidal action of the major phenolic components of oregano and clove essential oils – carvacrol and eugenol – was studied. This activity was also evaluated for the therapeutic efficacy in the treatment of the experimental oral candidiasis induced by Candida albicans in immunosuppressed rats.Methods:  In vitro, the addition of carvacrol at 0.1% or eugenol at 0.2% during the exponential growth of C. albicans was evaluated. The release of substances absorbing at 280 nm by cells treated with these two components was also measured spectrophotometrically. In vivo, oral candidiasis in immunosuppressed rats was established by inoculating 3 × 108 cells of C. albicans with a cotton swab on three alternate days. The number of colony counts was evaluated from the oral cavity of rats treated for eight consecutive days with carvacrol, eugenol or nystatin and compared to untreated controls.Results:  Carvacrol and eugenol were fungicidal in exponentially growing C. albicans. Interestingly, this fungicidal effect was accompanied by the release of substances absorbing at 280 nm. In an immunosuppressed rat model of oral candidiasis, carvacrol or eugenol treatment significantly (P < 0.05) reduced the number of colony counts sampled from the oral cavity of rats treated for eight consecutive days compared to untreated control rats. Similar results were obtained with nystatin used as a reference treatment.Conclusion:  The in vitro results indicated that both carvacrol and eugenol exerted an anticandidal effect by a mechanism implicating an important envelope damage. Their in vivo efficacy on experimental oral candidiasis leads us to consider them as possible antifungal agents.
Muscle Metabolic Changes Associated with Long‐term Inhalation Anaesthesia in the Horse Analysed by Muscle Biopsy and Microdialysis Techniques
Authors: Edner A. , Essén‐Gustavsson B. , Nyman G. 
Published: February 2005

SummaryDuring anaesthesia in the horse, muscle blood flow has been found to be reduced, possibly leading to hypoxia or ischaemia in the muscle. The aim of this study was to use the muscle biopsy and microdialysis techniques to determine whether long‐term inhalation anaesthesia in laterally recumbent horses induces metabolic changes in gluteal muscle indicative of anaerobic metabolism. Muscle biopsies and plasma samples were taken from seven horses at the start and end of halothane anaesthesia. In six isoflurane‐anaesthetised horses, given three pharmacological provocations (dobutamine, detomidine, acepromazine), repeated blood samples and microdialysis was performed during anaesthesia and muscle biopsies were taken before and at the end of anaesthesia. Adenosine triphosphate (ATP), adenosine diphosphate, adenosine monophosphate, inosine monophosphate (IMP) creatine phosphate and lactate concentrations did not differ between dependent and non‐dependent muscles at either sampling time. Creatine phosphate decreased in both the halothane (−38%) and isoflurane (−28%) group. In the halothane group, ATP was decreased (−15%) at the end of anaesthesia, while IMP was increased (+32%). Lactate in muscle and plasma increased in both groups. Lactate in dialysate increased after induction and remained elevated above plasma concentrations. These results show that long‐term inhalation anaesthesia in horses is associated with an anaerobic metabolic response within the muscle and that microdialysis can be used to detect metabolic changes within the muscle during equine anaesthesia.
Whither causal models in the neuroscience of ADHD?
Authors: Coghill Dave , Nigg Joel , Rothenberger Aribert , Sonuga‐Barke Edmund , Tannock Rosemary 
Published: February 2005

Abstract In this paper we examine the current status of the science of ADHD from a theoretical point of view. While the field has reached the point at which a number of causal models have been proposed, it remains some distance away from demonstrating the viability of such models empirically. We identify a number of existing barriers and make proposals as to the best way for these to be overcome in future studies. These include the need to work across multiple levels of analysis in multidisciplinary teams; the need to recognize the existence of, and then model, causal heterogeneity; the need to integrate environmental and social processes into models of genetic and neurobiological influence; and the need to model developmental processes in a dynamic fashion. Such a model of science, although difficult to achieve, has the potential to provide the sort of framework for programmatic model‐based research required if the power and sophistication of new neuroscience technologies are to be effectively exploited.
Varieties of preschool hyperactivity: multiple pathways from risk to disorder
Authors: Sonuga‐Barke Edmund J.S. , Auerbach Judith , Campbell Susan B. , Daley David , Thompson Margaret 
Published: February 2005

Abstract In this paper we examine the characteristics of preschool attention deficit hyperactivity disorder (ADHD) from both mental disorder and developmental psychopathology points of view. The equivalence of preschool and school‐aged hyperactivity as a behavioral dimension is highlighted together with the potential value of extending the use of the ADHD diagnostic category to the preschool period where these behaviours take an extreme and impairing form (assuming age appropriate diagnostic items and thresholds can be developed). At the same time, the importance of identifying pathways between risk and later ADHD is emphasized. Developmental discontinuity and heterogeneity are identified as major characteristics of these pathways. We argue that models that distinguish among different developmental types of early‐emerging problems are needed. An illustrative taxonomy of four developmental pathways implicating preschool hyperactivity is presented to provide a framework for future research.
Infants’ enumeration of actions: numerical discrimination and its signature limits
Authors: Wood Justin N. , Spelke Elizabeth S. 
Published: February 2005

Abstract Are abstract representations of number – representations that are independent of the particular type of entities that are enumerated – a product of human language or culture, or do they trace back to human infancy? To address this question, four experiments investigated whether human infants discriminate between sequences of actions (jumps of a puppet) on the basis of numerosity. At 6 months, infants successfully discriminated four‐ versus eight‐jump sequences, when the continuous variables of sequence duration, jump duration, jump rate, jump interval and duration, and extent of motion were controlled, and rhythm was eliminated. In contrast, infants failed to discriminate two‐ versus four‐jump sequences, suggesting that infants fail to form cardinal number representations of small numbers of actions. Infants also failed to discriminate between sequences of four versus six jumps at 6 months, and succeeded at 9 months, suggesting that infants’ number representations are imprecise and increase in precision with age. All of these findings agree with those of studies using visual–spatial arrays and auditory sequences, providing evidence that a single, abstract system of number representation is present and functional in infancy.
Validation of a Chinese version of the Dental Anxiety Inventory
Authors: Ng Sam K. S. , Stouthard Marlies E. A. , Keung Leung W. 
Published: February 2005

Abstract –  Objectives:  To translate the English version of Dental Anxiety Inventory (DAxI) and its short‐form (SDAxI) and to validate their use in Hong Kong Chinese.Methods:  The DAxI and SDAxI were translated into Chinese. A total of 500 adults (18–64 years) were interviewed, the Chinese DAxI, Symptom Checklist 90 (SCL‐90), Depression Anxiety Stress Scales (DASS) and State‐Trait Anxiety Inventory (STAI) were completed. Based on their initial DAxI scores, 135 interviewees were invited to attend a dental examination 1 month later. Then, the subjects completed the DAxI again, together with Beck Anxiety Inventory (BAI) which measured the state anxiety level of the participants. Two months after the initial interview, all 500 subjects were asked to complete the DAxI again. Another 300 adults were recruited and interviewed for the SDAxI validation.Results:  Cronbach's alpha of the Chinese DAxI and SDAxI were 0.77 and 0.80 and the test–retest correlation coefficients were 0.90 and 0.84, respectively. High correlation between BAI and DAxI scores and its stability over time supported construct validity of the Chinese DAxI. Small positive correlations between the DAxI and other subscales of the SCL‐90, DASS and STAI supported discriminant validity of the instrument. The SDAxI demonstrated comparable validity and reliability with DAxI.Conclusion:  The translated Chinese DAxI demonstrated good validity and reliability. It is available for use in dental anxiety research in adult Chinese. In situations where a short‐form is desirable, the Chinese SDAxI is a simple, valid, reliable and interpretable scale for measuring dental anxiety in both research and dental practice.