bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcriptional analysis of gtfB, gtfC, and gbpB and their putative response regulators in several isolates of Streptococcus mutans
Authors: Stipp R. N. , Gonçalves R. B. , Höfling J. F. , Smith D. J. , Mattos‐Graner R. O. 
Published: October 2008

Background:  Streptococcus mutans, a major dental caries pathogen, expresses several virulence genes that mediate its growth, accumulation on tooth surfaces, and acid‐mediated tooth demineralization. GtfB and GtfC catalyze the extracellular synthesis of water‐insoluble glucan matrix from sucrose, and are essential for accumulation of bacteria in the dental biofilm. GbpB, an essential protein of S. mutans, might also mediate cell‐surface interaction with glucan.Aim/methods:  In this study, we determined the transcription levels of gtfB, gtfC, and gbpB, and several putative transcriptional response regulators (rr) at different phases of planktonic growth in 11 S. mutans strains.Results:  Activities of gtfB and gtfC were growth‐phase dependent and assumed divergent patterns in several strains during specific phases of growth, while gbpB activities appeared to be under modest influence of the growth phase. Transcription patterns of the rr vicR, covR, comE, ciaR, and rr1 were growth‐phase dependent and some of these genes were expressed in a highly coordinated way. Each rr, except comE, was expressed by all the strains. Patterns of virulence and regulatory genes were, however, strain‐specific.Conclusions:  The findings suggest that mechanisms controlling virulence gene expression are variable among genotypes, providing the notion that the genetic diversity of S. mutans may have important implications for understanding mechanisms that regulate the expression of virulence genes in this species.
Sugar fermentation in probiotic bacteria – an in vitro study
Authors: Hedberg M. , Hasslöf P. , Sjöström I. , Twetman S. , Stecksén‐Blicks C. 
Published: October 2008

Introduction:  Food supplemented with probiotic bacteria is a rapidly growing sector of the market. The aim of the present study was to evaluate and compare the acid production of selected probiotic strains available in commercial products.Methods:  Six Lactobacillus strains (Lactobacillus plantarum 299v and 931; Lactobacillus rhamnosus GG and LB21; Lactobacillus paracasei subsp. paracasei F19, and Lactobacillus reuteri PTA 5289) were cultivated at 37°C in an anaerobic atmosphere on Man, Rogosa, Shape (MRS) agar for 48 h or MRS broth for 16 h. After centrifugation, the cells were washed and resuspended in sterile phosphate‐buffered saline and immediately subjected to a fermentation assay with 12 different carbohydrates (nine sugars and three sugar alcohols) in microtiter plates with a pH indicator. The plates were examined for color changes after 24, 48, and 72 h of incubation under aerobic and anaerobic conditions. Three scores were used: negative (pH > 6.8); weak (pH 5.2–6.8), and positive (pH < 5.2). The strains were characterized with the API 50 CH system to confirm their identity.Results:  L. plantarum fermented all the sugars except for melibiose, raffinose, and xylitol. Both L. rhamnosus strains were generally less active although L. rhamnosus GG was slightly more active than strain LB21 in the 5% CO2 setting. The latter strain exhibited negative reactions for sucrose, maltose, arabinose, and sorbitol under anaerobic conditions. The assays with L. paracasei and L. reuteri had negative or weak reactions for all tested sugars under both aerobic and anaerobic conditions.Conclusion:  The metabolic capacity to form acid from dietary sugars differed significantly between the various probiotic strains.
Human‐induced changes in the reproductive traits of Lake Constance common whitefish (Coregonus lavaretus)
Authors: THOMAS G. , QUOß H. , HARTMANN J. , ECKMANN R. 
Published: October 2008

AbstractSize‐selective fishery harvest leads to phenotypic changes in fish reproductive traits. When these changes represent an evolutionary response of a stock, they may have severe consequences for future stock dynamics and yields. In freshwater ecosystems, reproductive traits may also be affected by other human impacts such as changes in system productivity. The present study uses regression analysis to evaluate the impacts of changes in lake trophy and of an intensive size‐selective harvest over several decades on the reproductive traits of common whitefish in Lake Constance between 1963 and 1999. Fecundity was strongly linked to lake trophy but was also related to the calendar year, suggesting an evolutionary response to size‐selective harvest and to massive stocking of the lake with hatchery‐reared larvae. The present study is an example of how fish reproductive traits are influenced by the combined action of various human impacts: changes in system productivity, size‐selective harvest and massive stocking.
Experimental evidence that competition and habitat use shape the individual fitness surface
Authors: CALSBEEK R. 
Published: October 2008

AbstractA key prediction made by theories of density‐dependent competition is that resource overlap should increase the intensity of competition. By extension, we can predict that competition should lead to density‐dependent natural selection. I studied natural selection on limb length and body size in a total of seven populations ofAnolis sagreiover 3 years in the Bahamas. Experimental manipulations of population density on small off‐shore cays revealed that the strength of natural selection on body size increased with density, suggesting that density‐dependent intraspecific competition drives natural selection. At low density, reduced competition revealed significant selection on limb length driven by changes in perch diameter, indicating that selection favoured a match between morphology and habitat. The role habitat played in shaping selection was further illuminated by inter‐annual changes in vegetation structure stemming from variation in precipitation among years. Thus, changes in both the intensity of competition across spatial replicates, and in resource availability through time, revealed changes in the targets of natural selection. Results provide empirical support for the long‐standing hypothesis that density‐dependent natural selection shapes the fitness surface of Greater Antilles anoles.
Antennal Drumming, Trophallaxis, and Colony Development in the Social Wasp Polistes fuscatus (Hymenoptera: Vespidae)
Authors: Suryanarayanan Sainath , Jeanne Robert L. 
Published: October 2008

AbstractParental care is an important component of social behavior in both vertebrates and invertebrates. Social wasps are a useful system for investigating the interplay between behaviors associated with the feeding of larvae by adults and their role in the evolution and maintenance of sociality. Females of the primitively eusocial wasp genus Polistes perform conspicuous vibratory behaviors closely associated with adult–larva feeding interactions. Prior research strongly indicates that these signals are directed toward the larvae, but their function(s) remain unclear. Existing hypotheses on the function(s) have posited releaser effects on larvae, either stimulating or inhibiting release of larval saliva, a nutrient‐rich glandular secretion attractive to adults. Polistes fuscatus queens perform antennal drumming (AD), a behavior in which they rapidly beat their antennae synchronously on the rims of the nest cells during the feeding of larvae. We used radiolabeled prey to show that adults extract juice from the prey, which they subsequently regurgitate to larvae immediately following each AD burst. We also show that no saliva is imbibed by the queen during the contact. These results are consistent with the inhibition hypothesis on the function of AD, but not the stimulation hypothesis. We further demonstrate that AD is first performed on nests when the oldest larvae reach the third instar, and that the third instar is the first to produce measurable volumes of larval saliva. Removal of third‐, fourth‐, and/or fifth‐instar larvae from single‐foundress, pre‐pupal‐stage colonies did not cause a reduction in the queen’s AD rates compared with controls, suggesting that later‐stage larvae do not maintain AD behavior via an immediate releaser effect. We propose instead that third‐instar larvae, possibly via chemical components of the salivary secretion itself, modulate the physiology of queens so as to indirectly cause the onset and maintenance of AD behavior.
Life History of Learning: Performance Curves of Honeybees in the Wild
Authors: Dukas Reuven 
Published: October 2008

AbstractLearning is probably a major contributor to fitness in most animals yet it has not been well integrated into life history research. To quantify the role of learning in shaping lifetime patterns of performance, we must measure learning in natural settings as well as in controlled experimental conditions. As a part of a long‐term project measuring the relative contributions of learning, physiology, and effort to observed patterns of lifetime performance, I quantified the foraging success of worker honeybees in the wild. Bees exhibited a four‐fold increase in the net rate of food delivery to the colony over their first 4 d as foragers. The major contributors to that pattern were decreases in departure weights and increases in arrival weights. Combined with previous research, this study suggests that learning is the major contributor to the observed increases in lifetime performance, whereas age‐specific changes in physiology and effort have a significant though lesser role.
QTL mapping of BNYVV resistance from the WB258 source in sugar beet
Authors: Grimmer M. K. , Kraft T. , Francis S. A. , Asher M. J. C. 
Published: October 2008

AbstractRhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is an important sugar‐beet disease worldwide. The aim of this study was to investigate and map BNYVV resistance from the WB258 source. Presence of a major resistance gene (termed Rz5) was indicated by ∼1 : 1 segregation of virus levels in a population of 170 individuals derived from WB258. The maximum logarithm of odds (LOD) position for Rz5, identified by interval mapping, explained ∼81% of the phenotypic variance. Rz5 was mapped alongside the previously identified Rz4 from the R36 source. Rz4 and Rz5 were located to 6.9 cM and 6.0 cM regions, respectively, on chromosome III by interval mapping. These locations corresponded well to the position of the widely deployed Rz1 gene, suggesting that the three genes could represent an allelic series. Physical mapping is probably required to confirm this however. BNYVV resistance genes from novel sources are potentially important in breeding for more durable resistance either as separate genes or as BNYVV race‐specific alleles.
A Simple and Rapid PCR‐Based Method for Ostrich Sexing Using Micro Amounts of DNA
Authors: Huang C‐W , Huang M‐C 
Published: October 2008

ContentsThe aim of the present study is to identify ostrich sex by using polymerase chain reaction (PCR) on micro amounts of DNA from blood, bloodstain and feathers. Sixteen male and 18 female ostriches were used as test individuals. Genomic DNA as a template was extracted by the Chelex method. Ostrsex‐P1 and P2 primers were designed to perform PCR amplification on the template. PCR products were checked using agarose gel electrophoresis with ethidium bromide staining and ostrich sex was determined directly by the bands shown on the gel. The results demonstrate that ostrich sex can be determined by the extraction of DNA from as little as 0.0125 μl blood using Chelex, whereby the use of large amounts of organic solvents such as phenol and chloroform are unnecessary. In addition, it is possible to identify ostrich sex using micro amounts of DNA extracted from bloodstains and/or feathers. The use of feathers particularly avoids unwanted sampling problems such as the difficulty of collecting ostrich blood, the stress to the ostrich caused by bleeding, and the demand for a lot of manpower for ostrich restraint.
Vitrification of Bovine Blastocysts Produced In Vitro Inflicts Selective Damage to the Inner Cell Mass
Authors: Gómez E , Muñoz M , Rodríguez A , Caamaño JN , Facal N , Díez C 
Published: October 2008

ContentsIn contrast to the embryos derived from live animals, the embryos produced in vitro undergo increased damage and reduced survival after cryopreservation, particularly when produced with serum. In medium containing serum, retinoic acid increases cell numbers in the inner cell mass and the trophectoderm without altering their relative proportions in the bovine blastocyst. In this work, in medium without serum, we analyzed the contribution of retinoic acid to the development of blastocyst and survival to vitrification, and found a strong cell reduction in the inner mass when compared to the trophectoderm. Day‐6 in vitro‐produced morulae were treated for 24 h with retinoic acid (0.7 and 1.4 μm) and subsequently cultured without additives for a further 24 h period. Day‐8 blastocyst production and cell counts in hatched blastocysts were unaffected by retinoic acid. However, Day‐7 expanded, vitrified embryos produced with retinoic acid 1.4 μm survived at lower rates than controls when cultured after warming. Vitrification greatly reduced cell numbers in the inner mass (p < 0.0001), while cells in the trophectoderm remained unaltered. Differential cell counts analysis in blastocysts should be taken up to replace unspecific determination of total cells to appreciate substantial modifications in their exact terms. The strong reduction we found in the inner cell mass could explain why in vitro survival to cryopreservation is sometimes scarcely informative on the viability of the embryo after transfer to recipients.
Primary Unilateral Fibroleiomyoma of the Ovary in a Pregnant Mare: A Case Report
Authors: Carstanjen B , Schönert S , Heblinski N , Gruber AD 
Published: October 2008

ContentsFibroleiomyomas of the ovary are rare. This smooth muscle tumour may develop and increase in size during pregnancy. Diagnosis is based on histological and immunohistochemical analyses. Histologically, the ovarian fibroleiomyoma consists of non‐invasive bundles of smooth muscle cells that synthesize collagen‐like extracellular matrix. This case report describes an ovarian fibroleiomyoma in a pregnant multiparous broodmare with a history of intermittent signs of colic.
Cervical Hypoplasia in Jennets: A Description of Two Cases
Authors: Payan‐Carreira R , Quaresma M 
Published: October 2008

ContentsThe authors describe two cases of cervical hypoplasia in jennets, detected during the gynaecological evaluation of two purebred females of the Portuguese donkey breed Asinina de Miranda. These jennets aged 10 and 15 years were referred for consultation by the local breeders association because of infertility detected during an artificial breeding programme. In both jennets the cervix was small, shorter than the usual and closed. In one of the females, outflow of semen during artificial insemination was reported. Clinical and ultrasonographic evaluation of the genital tract demonstrated that both ovaries were normally sized in both animals and presenting structures suggestive of regular ovarian activity. In one of the jennets, a small amount of air in the uterus was evidenced. In the other, signs indicative of atresia of the cervical canal were found. Vaginal examination showed that the cervix was reduced in size and shallowed in both animals. A diagnosis of congenital cervical hypoplasia was made in both cases and the animals were excluded from reproduction.
The burden of lung disease in Hong Kong: A report from the Hong Kong Thoracic Society
Authors: CHAN‐YEUNG Moira , LAI Christopher K.W. , CHAN Kin‐Sang , CHEUNG Amy H.K. , YAO Tzy‐Jyun , HO Alice S.S. , KO Fanny W. , YAM Loretta Y. , WONG Poon‐Chuen , TSANG Kenneth W. , LAM Wah‐Kit , HO James C. , CHU Chung‐Ming , YU Wai‐Cho , CHAN Hok‐Sum , IP Mary S.M. , HUI David S. , TAM Cheuk‐Yin 
Published: October 2008

Background and objective:  The burden of lung disease in Hong Kong is not known. This study determined the mortality and hospitalization rates of respiratory diseases in Hong Kong in 2005, their trend in the past decade and their incidence/prevalence.Methods:  Mortality data were obtained from the Department of Health and hospitalization data from the Hospital Authority, Hong Kong. Incidence/prevalence data were obtained from local registries or local studies. Trends of mortality and hospitalization rates of various respiratory diseases from 1997 and 2005 were calculated after age standardization and were tested for significance using negative binomial regression analysis. Age standardized mortality rates in Hong Kong were compared with those of the UK and globally.Results:  Respiratory disease was the most common cause of mortality and hospitalization in Hong Kong in 2005. Globally and in the UK, cardiovascular disease ranked first in mortality. Respiratory infections ranked first in respiratory mortality, followed by respiratory tract cancer and chronic obstructive lung disease. Respiratory infections also ranked first followed by chronic obstructive lung disease in the utilization of respiratory inpatient bed‐days. While mortality rates from all respiratory diseases decreased in the past decade, hospitalization rates remained unchanged. Unlike other respiratory diseases, mortality from respiratory infections have increased since 2001. Smoking is the most important risk factor in non‐communicable respiratory diseases.Conclusions:  Respiratory disease is responsible for the highest health‐care burden locally. Increased efforts in improving management and prevention of these diseases, including tobacco control, improving air quality and vaccination against influenza and pneumococci, are necessary.
Hypocretin /orexin preferentially activates caudomedial ventral tegmental area dopamine neurons
Authors: Vittoz Nicole M. , Schmeichel Brooke , Berridge Craig W. 
Published: October 2008

AbstractThe hypocretin/orexin (HCRT) neuropeptide system modulates behavioral state and state‐dependent processes via actions on multiple neuromodulatory transmitter systems. Recent studies indicate that HCRT selectively increases dopamine (DA) neurotransmission within the prefrontal cortex (PFC) and the shell subregion of the nucleus accumbens (NAs), but not the core subregion of the nucleus accumbens (NAc). The circuitry underlying the differential actions of HCRT across distinct DA systems is unclear. The current study examined whether HCRT preferentially activates PFC‐ and NAs‐projecting relative to NAc‐projecting DA neurons within the VTA. One week after infusion of the retrograde tracer fluorogold (FG) into the medial PFC, NAc or NAs, animals received a ventricular infusion of HCRT‐1. Subsequent analyses conducted across the rostral‐caudal extent of the VTA determined the degree to which: (i) Fos‐immunoreactivity (ir) was observed within tyrosine hydroxylase (TH)‐ir neurons; (ii) TH‐ir was observed within FG‐ir neurons; and (iii) Fos‐ir was observed within FG‐ir neurons. HCRT significantly increased Fos‐ir in VTA DA (TH‐ir) neurons, primarily in a restricted population of small‐to‐medium‐sized DA neurons located within the caudomedial VTA. Furthermore, within this region of the VTA, PFC‐ and NAs‐projecting TH‐ir neurons were more likely to contain Fos‐ir than were NAc‐projecting TH‐ir neurons. These results provide novel evidence that HCRT selectively activates PFC‐ and NAs‐projecting DA neurons within the VTA, and suggest a potential role for HCRT in PFC‐ and NAs‐dependent cognitive and/or affective processes. Moreover, these and other observations suggest that the dysregulation of HCRT–DA interactions could contribute to cognitive/affective dysfunction associated with a variety of behavioral disorders.
The economic impact of overactive bladder syndrome in six Western countries
Authors: Irwin Debra E. , Mungapen Laura , Milsom Ian , Kopp Zoe , Reeves Penny , Kelleher Con 
Published: October 2008

OBJECTIVETo calculate up‐to‐date estimates of the economic impact of overactive bladder syndrome (OAB) with and without urgency urinary incontinence (UUI) on the health sector of six countries (Canada, Germany, Italy, Spain, Sweden and the UK), as OAB is a significant health concern for adults aged >18 years living in Western countries.MATERIALS AND METHODSThe prevalence data derived from the EPIC study were combined with healthcare resource‐use data to derive current direct and indirect 1‐year or annual cost of illness estimates for OAB including UUI in Canada, Germany, Italy, Spain, Sweden and the UK. This model estimates the direct healthcare costs attributed to OAB, as well as the impact of work absenteeism.RESULTSThe estimated average annual direct cost of OAB per patient ranged between €262 in Spain and €619 in Sweden. The estimated total direct cost burden for OAB per country ranges between €333 million in Sweden and €1.2 billion in Germany and the total annual direct cost burden of OAB in these six countries is estimated at €3.9 billion. In addition, nursing home costs were estimated at €4.7 billion per year and it was estimated that work absenteeism related to OAB costs €1.1 billion per year.CONCLUSIONSThe cost of illness for OAB is a substantial economic and human burden. This study may under‐estimate the true economic burden, as not all costs for sequelae associated with OAB have been included. Cost‐effective treatments and management strategies that can reduce the burden of OAB and in particular UUI have the potential to significantly reduce this economic burden.
Sex differences in past tense overregularization
Authors: Kidd Evan , Lum Jarrad A.G. 
Published: October 2008

Abstract
Hartshorne and Ullman (2006

) presented naturalistic language data from 25 children (15 boys, 10 girls) and showed that girls produced more past tense overregularization errors than did boys. In particular, girls were more likely to overregularize irregular verbs whose stems share phonological similarities with regular verbs. It was argued that the result supported the Declarative/Procedural model of language, a neuropsychological analogue of the dual‐route approach to language. In the current study we present experimental data that are inconsistent with these naturalistic data. Eighty children (40 males, 40 females) aged 5;0–6;9 completed a past tense elicitation task, a test of declarative memory, and a test of non‐verbal intelligence. The results revealed no sex differences on any of the measures. Instead, the best predictors of overregularization rates were item‐level features of the test verbs. We discuss the results within the context of dual versus single route debate on past tense acquisition.
Biological and environmental initial conditions shape the trajectories of cognitive and social‐emotional development across the first years of life
Authors: Feldman Ruth , Eidelman Arthur I. 
Published: October 2008

Abstract Human development is thought to evolve from the dynamic interchange of biological dispositions and environmental provisions; yet the effects of specific biological and environmental birth conditions on the trajectories of cognitive and social‐emotional growth have rarely been studied. We observed 126 children at six time‐points from birth to 5 years. Intelligence, maternal sensitivity, and child social engagement were repeatedly tested. Effects of neonatal vagal tone (VT) and maternal postpartum depressive symptoms on growth‐rates were assessed. Cognitive development showed a substantial growth‐spurt between 2 and 5 years and social engagement increased rapidly across the first year and more gradually thereafter. VT improved cognitive and social‐emotional growth‐rates across the first year, whereas maternal depressive symptoms interfered with growth from 2 to 5 years. Differences between infants with none, one, or two non‐optimal birth conditions increased with age. Findings shed light on the dynamics of early development as it is shaped by biological and environmental initial conditions.