bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research‐based interventions for children and youth with a Fetal Alcohol Spectrum Disorder: revealing the gap
Authors: Premji S. , Benzies K. , Serrett K. , Hayden K. A. 
Published: October 2006

AbstractBackground  Alcohol use during pregnancy can result in a continuum of effects including growth deficits, dysmorphology and/or complex patterns of behavioural and cognitive difficulties that influence an individual’s functioning throughout their lifespan. We conducted a systematic review to identify research‐based interventions for children and youth with a Fetal Alcohol Spectrum Disorder and areas for future study.Methods  We identified the substantive literature by searching 40 peer‐reviewed and 23 grey literature databases, as well as reference lists. We hand‐searched eight relevant journals, and undertook a systematic search of Internet sites and review of reports and documents received from key stakeholders. Two reviewers independently assessed eligibility and quality, and extracted data. Given the small number of studies that met all inclusion criteria, both experimental and quasi‐experimental studies were included.Results  Ten intervention studies were identified, of which three were experimental or quasi‐experimental, and four were non‐experimental. Despite multiple attempts, three studies (two in foreign languages and one unpublished) could not be acquired. A meta‐analysis could not be undertaken because the included studies examined different interventions or outcomes. Interventions targeted in the included studies were as follows: (i) psychostimulant medications (methyphenidate, pemoline and dextroamphetamine); and (ii) Cognitive Control Therapy. The identified studies were limited by very small sample sizes and weak designs.Conclusion  There is limited scientific evidence upon which to draw recommendations regarding efficacious interventions for children and youth with a Fetal Alcohol Spectrum Disorder. Clinicians, researchers, service providers, educators, policy makers, affected children and youth and their families, and others need to urgently collaborate to develop a comprehensive research agenda for this population.
Associations between youth assets and sexual activity: does adult supervision play a role?
Authors: Harris L. , Oman R. F. , Vesely S. K. , Tolma E. L. , Aspy C. B. , Rodine S. , Marshall L. , Fluhr J. 
Published: October 2006

AbstractBackground  Youth participation in sexual risk behaviours continues to be a critically important public health topic. Additionally, as youth are frequently being left alone during the day without adult supervision, there are increased opportunities for sexual risk‐taking behaviour. This study examined how the relationships of nine youth assets and sexual activity may vary according to the stratification of youth into two groups: self‐care and supervised.Methods  Data were collected through at‐home, in‐person interviews from a random sample of inner‐city youth (mean age = 15.4 years; 51.5% female; 48.8% White; 22.4% Black; 18.5% Hispanic; 10% Native American) and their parents (n = 1079 parent/youth pairs). Nine youth assets were analysed using multiple logistic regression. Examples of assets youth may possess are: positive role models, family communication, school connectedness, constructive use of time and aspirations for the future. The item used to assess sexual intercourse was ‘Have you ever had sexual intercourse (“done it”, “had sex”, “made love”, “gone all the way”)?’. Asset/risk behaviour associations that were unique to one of the two strata were the focus of the study.Results  Thirty‐seven per cent of youth spent two or more hours per day home alone. Youth who were supervised had a greater number of unique significant associations between assets and sexual activity than youth who were in the self‐care group.Conclusions  Youth in supervised settings may be less likely to participate in sexual activity because of the presence of assets. Certain assets may also be important in deterring sexual activity for youth who are in self‐care.
Competition between two planktonic rotifer species at different temperatures: an experimental test
Authors: STELZER CLAUS‐PETER 
Published: October 2006

Summary1. The effect of temperature on the outcome of resource competition between two planktonic rotifers (Synchaeta pectinata and Brachionus calyciflorus) was investigated in laboratory experiments. In addition to the competition experiments, several physiological variables and their temperature‐dependence were characterised, including ingestion rate and starvation tolerance.2. Because of a lower threshold food level (TFL) for population growth for the food algae Cryptomonas erosa, Synchaeta was predicted to be the superior competitor at low temperatures (12 °C). In contrast, Brachionus had a lower TFL at 20 °C and was predicted to be competitively superior at this temperature.3. In both rotifer species, ingestion rates increased with temperature, but the increase was much more pronounced in Brachionus. Ingestion rates of Brachionus at temperatures from 8 to 24 °C were always higher than in Synchaeta (up to 4.6‐fold).4. Starvation resistance reduced with temperature in both rotifer species. At all temperatures investigated (12, 16 and 20 °C) Brachionus could survive starvation for longer than Synchaeta. This difference was strongest at 12 °C (5.8 days versus 2.5 days).5. In the first competition experiment, food was supplied at 48 h‐intervals. Brachionus displaced Synchaeta at both experimental temperatures (12 and 20 °C). Competitive exclusion of Synchaeta at the lower temperature was probably because of large fluctuations in algal densities that resulted from the long intervals between feeding, a condition that favoured Brachionus because of its higher starvation resistance.6. In the second competition experiment, one third of the food suspension was renewed every 8 h, resulting in a much better approximation to a continuous resource supply. At 12 °C Synchaeta and Brachionus coexisted for more than 1 month and the densities of both rotifer species were significantly lower in the presence of their competitor. In contrast to expectations, Brachionus was able to persist even when Cryptomonas concentrations fell below its TFL. This was probably because Brachionus was using detritus and associated bacteria as additional food sources, which were present in the cultures during the later phase of the experiment.7. Autocorrelation analysis of the temporal changes in egg ratios revealed significant periodic cycles in Synchaeta during the second competition experiment. A possible explanation for this is the fecundity schedule of Synchaeta, in which reproduction is highly concentrated in a few age classes. According to demographic theory, such a life cycle feature can cause slower convergence to a stable age distribution.
Fish and mucus‐dwelling bacteria interact to produce a kairomone that induces diel vertical migration in Daphnia
Authors: BEKLIOGLU MERYEM , TELLI MURAT , GOZEN AYSE G. 
Published: October 2006

Summary1. Bacterial populations associated with fish have previously been documented to be crucial for the production of chemical signals governing the interactions between predator fish and zooplankton prey.2. In this study, we investigated the roles of fish and mucus‐dwelling bacteria in kairomone production by conducting two sets of experiments related to elimination of bacteria with antibiotics and using fish mucus in bioassays of Daphnia pulex’s diel vertical migration.3. Daphnia’s migratory response to the antibiotic‐treated fish was about half the strength of the response to the fish cue treatment. Furthermore, when the same antibiotic‐treated fish were removed from the antibiotic‐containing water and transferred into control water for 24 and 48 h, the extent of D. pulex’s migration depended on the length of the incubation period, apparently corresponding to the regeneration of bacterial colonies associated with mucus. The migration pattern observed in the 24 h treatment was similar to that of antibiotic‐treated fish. On the other hand, a pronounced migration occurred in the 48 h following antibiotic treatment; here, we found a higher density of fish surface dwelling bacteria than at the start of the experiment.4. In the experiment involving fish mucus, the mucus‐enriched control water induced a weak response similar to antibiotic‐treated fish.5. On the basis of the results from the two experiments, we suggest that both fish and fish mucus‐dwelling bacteria interact in the release of kairomone in ecologically relevant quantities.
Does excess carbon affect respiration of the rotifer Brachionus calyciflorus Pallas?
Authors: JENSEN THOMAS C. , ANDERSON THOMAS R. , DAUFRESNE MARTIN , HESSEN DAG O. 
Published: October 2006

Summary1. Herbivorous zooplankton maintain a rather constant elemental composition in their body mass as compared with the variability commonly encountered in their food. Furthermore, their high phosphorus (P) and nitrogen (N) content means that they often face an excess of carbon (C) in their diet. Regulation of this surplus of energy may occur via modulation of assimilation efficiency, or postassimilation by increased respiration (CO2) and/or excretion dissolved organic carbon, DOC. Whereas several studies have examined the effect of elemental imbalance in the genus Daphnia, few have examined other zooplankton taxa.2. We investigated whether the rotifer Brachionus calyciflorus uses increased respiration as a means of stoichiometrically regulating excess dietary C. Growth rate and respiration were measured under different food qualities (C : N and C : P ratios).3. Both C : N and C : P ratios in food had strong effects on growth rate, demonstrating strong nutrient limitation of rotifer growth when nutrient elements were depleted in the diet and indicating the need for stoichiometric regulation of excess ingested C.4. Respiration measurements, supported by a stoichiometric model, indicated that excess C was not released as CO2 in B. calyciflorus and that nutrient balance must therefore be maintained by other means such as excretion of DOC or egestion in faecal material.
Large‐scale spatial and temporal dynamics of the vulnerable and highly mobile superb parrot
Authors: Manning Adrian D. , Lindenmayer David B. , Barry Simon C. , Nix Henry A. 
Published: October 2006

AbstractAim  To investigate the spatial and temporal dynamics of the vulnerable and highly mobile superb parrot (Polytelis swainsonii) across its range in south‐eastern mainland Australia.Location  South‐eastern Australia (27°–37° S latitude and 141°–151° E longitude).Methods  We used generalized additive models (GAMs) to model time‐specific bird atlas occurrence data against time‐specific plant productivity data, plus a range of environmental predictor variables. We then examined the effects of environmental variables on the temporal and spatial patterns of predicted abundance and distribution of the superb parrot using a correlative mapping approach.Results  Key findings from GAM analysis were: (1) there was a strong positive relationship between abundance and plant productivity in all regions, but (2) the response of abundance to other predictor variables often differed between regions. Correlative mapping predictions of the abundance and distribution of the superb parrot also indicated that: (1) predicted abundance varied through time and space, (2) predicted abundance sometimes decreased in all regions, but at other times some regions had high abundance when others had low, and (3) changes in plant productivity (and therefore climate) were associated with this variation.Main conclusion  The superb parrot favours productive landscapes that are also favoured for agriculture. Movements appear to be associated with seasonal and year to year climate variability. Thus, variation in the recorded abundance of the superb parrot may mask population trends, suggesting that existing population estimates are unreliable. Also, high abundances in some areas, and at some times, may reflect deteriorating habitat conditions elsewhere rather than species recovery. Temporal variability in the distribution of the superb parrot makes it difficult to identify specific drought refugia. Consequently, through time, as key habitat continues to deteriorate, the species will become increasingly vulnerable and threatened. Whole‐landscape habitat conservation and restoration strategies are therefore needed to sustain superb parrot populations in the long‐term.
Spatial patterns and vegetation–site relationships of the presettlement forests in western New York, USA
Authors: Wang Yi‐Chen 
Published: October 2006

AbstractAim  The purposes of this study were to develop a Geographic Information System and spatial analytical methodology to reconstruct and represent the presettlement vegetation in a spatially continuous manner over large areas and to investigate vegetation–site relationships before widespread changes of the vegetation had taken place.Location  The study area was the Holland Land Company Purchase in western New York, a 14,400 km2 area extending across the physiographic provinces of the Erie–Ontario Lowlands and the Appalachian Uplands.Methods  Bearing‐tree records from the Holland Land Company township surveys of western New York in c. 1800 were collected and analysed. The geostatistical method of indicator kriging was used to map spatially continuous representations of individual tree species. Rule‐based and statistically clustered approaches were used to analyse and classify the reconstructed tree species distributions in order to obtain the vegetation association distribution. Contingency table analysis was conducted to quantify species relationships with soil conditions.Results  The presettlement vegetation at both the tree species and the vegetation association levels were easier to interpret and visually more effective as a spatially continuous representation than as a discontinuous distribution of symbols. The results for tree species were probability occurrences of species distribution, showing spatial patterns that were not apparent in discrete maps of points or in summary tables of species frequencies. Analysis of the 8792 bearing trees suggested the dominance of American beech (Fagus grandifolia) and sugar maple (Acer saccharum) in the forest composition 200 years ago. Both soil drainage and texture were important site determinants of the vegetation in western New York. The rule‐based and statistically clustered approaches had the advantage of summarizing vegetation compositional patterns in a single image, thus avoiding the need to delineate manually and subjectively the location of boundaries between adjacent vegetation associations.Main conclusions  The study offers more insights into the spatial pattern of presettlement forests in western New York than do prior studies. The spatially continuous representation could also enable the comparison of vegetation distribution from data sources that have different sampling schemes, for example the comparison of presettlement vegetation from the presettlement land survey records with current vegetation from modern forest inventories. The results are of value, providing a useful benchmark against which to examine vegetation change and the impacts of human land use.
The impact of quorum sensing and swarming motility on Pseudomonas aeruginosa biofilm formation is nutritionally conditional
Authors: Shrout Joshua D. , Chopp David L. , Just Collin L. , Hentzer Morten , Givskov Michael , Parsek Matthew R. 
Published: October 2006

SummaryThe role of quorum sensing in Pseudomonas aeruginosa biofilm formation is unclear. Some researchers have shown that quorum sensing is important for biofilm development, while others have indicated it has little or no role. In this study, the contribution of quorum sensing to biofilm development was found to depend upon the nutritional environment. Depending upon the carbon source, quorum‐sensing mutant strains (lasIrhlI and lasRrhlR) either exhibited a pronounced defect early in biofilm formation or formed biofilms identical to the wild‐type strain. Quorum sensing was then shown to exert its nutritionally conditional control of biofilm development through regulation of swarming motility. Examination of pilA and fliM mutant strains further supported the role of swarming motility in biofilm formation. These data led to a model proposing that the prevailing nutritional conditions dictate the contributions of quorum sensing and swarming motility at a key juncture early in biofilm development.
Concerted action of plasmid maintenance functions: partition complexes create a requirement for dimer resolution
Authors: Bouet Jean‐Yves , Bouvier Marie , Lane David 
Published: October 2006

SummaryPartition of prokaryotic DNA requires formation of specific protein–centromere complexes, but an excess of the protein can disrupt segregation. The mechanisms underlying this destabilization are unknown. We have found that destabilization by the F plasmid partition protein, SopB, of plasmids carrying the F centromere, sopC, results from the capacity of the SopB–sopC partition complex to stimulate plasmid multimerization. Mutant SopBs unable to destabilize failed to increase multimerization. Stability of wild‐type mini‐F, whose ResD/rfsF site‐specific recombination system enables it to resolve multimers to monomers, was barely affected by excess SopB. Destabilization of plasmids lacking the rfsF site was suppressed by recF, recO and recR, but not by recB, mutant alleles, indicating that multimerization is initiated from single‐strand gaps. SopB did not alter the amounts or distribution of replication intermediates, implying that SopB–DNA complexes do not create single‐strand gaps by blocking replication forks. Rather, the results are consistent with SopB–DNA complexes channelling gapped molecules into the RecFOR recombination pathway. We suggest that extended SopB–DNA complexes increase the likelihood of recombination between sibling plasmids by keeping them in close contact prior to SopA‐mediated segregation. These results cast plasmid site‐specific resolution in a new role – compensation for untoward consequences of partition complex formation.
Global transcriptional upregulation in the absence of increased translation in Chlamydia during IFNγ‐mediated host cell tryptophan starvation
Authors: Ouellette Scot P. , Hatch Thomas P. , AbdelRahman Yasser M. , Rose Lorne A. , Belland Robert J. , Byrne Gerald I. 
Published: October 2006

SummaryThe developmentally regulated intracellular pathogen Chlamydia pneumoniae is a natural tryptophan auxotroph. These organisms survive tryptophan starvation induced by host cell activation with IFNγ by blocking maturation to the infectious form. In most bacteria, the stringent response is induced during amino acid starvation to promote survival. However, the response of obligate intracellular pathogens, which are predicted to lack stringent responses to amino acid starvation, is poorly characterized. Chlamydial transcription and translation were analysed during IFNγ‐mediated tryptophan starvation using genomic normalization methods, and the data revealed the novel findings that: (i) global chlamydial transcription was upregulated; and (ii) protein synthesis was dramatically reduced. These results indicate a dysregulation of developmental gene expression and an uncoupling of transcription from translation. These observations represent an alternative survival strategy for host‐adapted obligate intracellular bacterial pathogens that have lost the genes for stringent control during reductive evolution.
Netherton syndrome: Successful use of topical tacrolimus and pimecrolimus in four siblings
Authors: Saif Ghada Bin , Al‐Khenaizan Sultan 
Published: October 2006

AbstractNetherton's syndrome (NS) is a rare autosomal recessive disease comprised of ichthyosis in the form of ichthyosis linearis circumflexa, hair shaft defects and atopic manifestations with an elevated IgE level. Various therapeutic options have been used in NS with variable success. Tacrolimus and pimecrolimus belong to the family of calcineurin inhibitors. They bind cytoplasmic proteins and the resulting complex binds calcineurin, inhibiting its ability to dephosphorylate the nuclear factor of activated T cells, thus suppressing gene transcription. There have been conflicting reports of the usefulness of tacrolimus in NS patients, with systemic absorption being the main adverse outcome. Here we report four Saudi siblings (two boys and two girls) with NS who were treated with topical tacrolimus and pimecrolimus with good control of their skin disease without any toxic effect. To our knowledge, this is the second report of the use of topical pimecrolimus in NS in the English literature.
99mTc‐MIBI imaging of cutaneous AIDS‐associated Kaposi's sarcoma
Authors: Peer Fawzia I. , Pui Margaret H. , Mosam Anisa , Rae William I. D. 
Published: October 2006

AbstractBackground  Kapoksi's sarcoma (KS) is a common neoplasm complicating acquired immunodeficiency syndrome (AIDS). Skin, mucus membranes, lymph nodes, gastrointestinal tract and lungs may be involved. Kaposi's sarcoma has been demonstrated by scintigraphy, and a 99mTc‐hexakis‐2‐methoxy isobutyl isonitrile (MIBI) scan can demonstrate lymphoma and tumors of the brain, nasopharynx, thyroid, parathyroid, lung, breast and kidney. It may also be useful for detecting and delineating the extent of KS. The objective of this study was to determine the efficacy of 99mTc‐MIBI scanning to demonstrate cutaneous AIDS‐associated KS, lymphedema and lymphadenopathy in the extremities.Methods  Whole body 99mTc‐MIBI scans were obtained on 40 patients with AIDS‐associated KS. Abnormal uptake of 99mTc‐MIBI in the skin, subcutaneous soft tissues and lymph nodes was compared with the clinical assessment.Results  The 99mTc‐MIBI uptake was noted in the cutaneous/subcutaneous KS of the extremities with a sensitivity of 73.53%, a specificity of 96.91% and an accuracy of 91.31%. Abnormal lymph nodes and lymphedema were detected in more patients on 99mTc‐MIBI scans (33 and 18 patients) than clinical assessment (10 and 12 patients), respectively. Lymphedema of the lower extremity was found in four of 17 patients without any palpable or abnormal lymph node uptake of 99mTc‐MIBI in the inguinal regions. Follow‐up 99mTc‐MIBI scans after treatment showed no uptake in the skin lesions and decreased uptake in the lymph nodes corresponding to complete clearing on clinical assessment.Conclusions  99mTc‐MIBI imaging provides additional information on the extent of lymph node involvement and more precise staging and therapeutic planning. It may be useful as a predictive test or follow up of response of cutaneous KS to treatment.
Cutaneous leishmaniasis reactivation 2 years after treatment caused by systemic corticosteroids – first report
Authors: Tuon Felipe Francisco , Sabbaga Amato Valdir , Floeter‐Winter Lucile Maria , De Andrade Zampieri Ricardo , Amato Neto Vicente , Siqueira França Francisco Oscar , Shikanai‐Yasuda Maria Aparecida 
Published: October 2006

AbstractAmerican tegumentary leishmaniasis (ATL), an endemic anthropozoonosis in various countries in the world, is caused by parasites of the genus Leishmania. Despite reports on ATL reactivation as a result of immunosuppression, to the best of our knowledge, this paper describes the first case of ATL reactivation in its localized form (cutaneous leishmaniasis) associated with the administration of systemic corticosteroids. The possible action of corticosteroids on the host immune response to the parasite in patients with localized cutaneous leishmaniasis is discussed. This report demonstrates the possibility of ATL reactivation in patients using corticosteroids, an observation that should be considered in individuals treated with this medication.