bluuebunny/crossref_metadata_2025 huggingface dataset:
School Psychology in Nova Scotia
Authors: Corkum Penny , French Fredrick , Dorey Harvey
Published: June 2007

School psychologists working in Nova Scotia (NS) were surveyed to determine their current practices and preferred future roles. The goals of the study were to: (a) provide insight into the practice of school psychology in NS, (b) compile a valuable resource for potential students entering into the field, (c) provide information for educational programs preparing school psychology students, and (d) encourage interprovincial communication across the Canadian provinces. Results of the surveys indicate that there have been dramatic changes in the practice of school psychology in NS over the past two decades. Along with increasing numbers of positions and more specific training, there has been an increase in time spent in psychoeducational assessment as well as further diversification of roles (intervention, prevention, consultation). There is a strong desire to decrease time spent in the psychoeducational role and increase time in the area of preventative services. Implications for practicing and upcoming school psychologists are discussed.
Patterns of Cognitive Functioning in a Clinic-Referred Sample of Preschool Children
Authors: Koushik Nikhil S. , Saunders Cory D. , Rourke Byron P.
Published: June 2007

This study examined patterns of performance on the Wechsler Preschool and Primary Scale of Intelligence—Revised (WPPSI-R) and the relationship of these patterns to diagnoses of behavioural problems. The sample consisted of 108 children between age 3 and 7 years inclusive who had been referred to a day-treatment program for a wide variety of psychological difficulties. All children had Full Scale IQ scores between 50 and 130. Two-stage cluster analysis identified five reliable subtypes. Three of these were differentiated primarily by level of performance (low, average, and high). The other two were differentiated primarily by pattern of performance: one characterized by nonverbal deficits and the other by verbal deficits. Findings also revealed that the children's previous diagnoses were relatively consistent with their patterns of performance on the WPPSI-R. The significance of these findings in relation to previous research in this area is discussed, and suggestions for future investigations are formulated.
Longitudinal Effects of Domestic Violence on Employment and Welfare Outcomes
Authors: Lindhorst Taryn , Oxford Monica , Gillmore Mary Rogers
Published: June 2007

This study uses longitudinal data spanning 13 years from a study of 234 adolescent mothers to evaluate the effects of cumulative domestic violence on employment and welfare use before and after welfare reform. Domestic violence increased the odds of unemployment after welfare reform, but not before; domestic violence had no effect on welfare use during any time period. Psychological distress after welfare reform was associated with unemployment, but not with welfare outcomes. Thus, the authors found that the direct effect of domestic violence on unemployment is not mediated by concurrent level of psychological distress. The relationship of psychological distress to unemployment exists only for those with a history of domestic violence. Cumulative domestic violence can have negative effects on economic capacity many years after the violence occurs, suggesting that policymakers recognize the long-term nature of the impact of domestic violence on women's capacity to be economically self-reliant.
Uniting Spirituality and Sexual Counseling: Semitic Traditions
Authors: Turner Tommy E. , Fox Nancy J. , Kiser Jerry D.
Published: June 2007

A barrier between spirituality and counseling appears to be fading away as the quest for spiritual understanding expands. Practitioners who unite sexual counseling and spirituality must not only examine their personal experiences, values, and beliefs in the spiritual realm, but must also become familiar with a wide array of spiritual traditions that clients can and will bring to the counseling process. This article provides information about spirituality and sexuality from both Islamic and Jewish perspectives.
Identification of a distant T-bet enhancer responsive to IL-12/Stat4 and IFNγ/Stat1 signals
Authors: Yang Yu , Ochando Jordi C. , Bromberg Jonathan S. , Ding Yaozhong
Published: June 2007

T-bet plays a critical role in controlling IFNγ expression, Th1 polarization, and CD8 cytolytic development. Its regulation has been demonstrated to be mostly IFNγ/Stat1 dependent while IL-12/Stat4 independent. Here we show that IL-12/Stat4 binds to a distant highly conserved STAT-responsive T-bet enhancer, and induces IFNγ/Stat1-independent T-bet expression in CD8 T cells. Luciferase reporter assay showed that both Stat4 and Stat1 activate reporter gene expression from constructs containing a wild-type but not mutated T-bet enhancer. Studies in virus-infected mice demonstrated that the IL-12/Stat4/T-bet cascade operates in vivo and regulates IFNγ in CD8 T cells. Together, we provide a novel mechanism for T-bet regulation, and suggest that IL-12/Stat4/T-bet play an important role in CD8 effector responses.
OX40 costimulation turns off Foxp3+ Tregs
Authors: Vu Minh Diem , Xiao Xiang , Gao Wenda , Degauque Nicolas , Chen Ming , Kroemer Alexander , Killeen Nigel , Ishii Naoto , Chang Li Xian
Published: June 2007

OX40 is a recently identified T-cell costimulatory molecule that belongs to the TNF/TNFR superfamily. OX40 can be expressed by both activated T effector cells and Foxp3+ Tregs. It is well known that OX40 delivers a potent costimulatory signal to T effector cells, but very little is known about the role of OX40 in regulating the suppressor properties of Foxp3+ Tregs and the de novo generation of new inducible Foxp3+ Tregs from T effector cells. In the present study, we found, by using a newly created foxp3gfp knockin model, that OX40 was dispensable for the genesis and suppressor functions of naturally arising CD4+Foxp3+ Tregs, but stimulating OX40 on the Foxp3+ Tregs abrogated their ability to suppress T effector cell proliferation, IFN-γ production, and T effector cell-mediated allograft rejection. OX40 costimulation did not significantly affect proliferation and survival of the naturally arising Foxp3+ Tregs, but profoundly inhibited Foxp3 gene expression. Importantly, OX40 costimulation to T effector cells prevented the induction of new inducible Foxp3+ Tregs from T effector cells. Our study identified OX40 as a key negative regulator of Foxp3+ Tregs and may have important clinical implications in models of transplantation and autoimmunity.
Selecting dissimilar genes for multi-class classification, an application in cancer subtyping
Authors: Cai Zhipeng , Goebel Randy , Salavatipour Mohammad R , Lin Guohui
Published: June 2007

Background

Gene expression microarray is a powerful technology for genetic profiling diseases and their associated treatments. Such a process involves a key step of biomarker identification, which are expected to be closely related to the disease. A most important task of these identified genes is that they can be used to construct a classifier which can effectively diagnose disease and even recognize the disease subtypes. Binary classification, for example, diseased or healthy, in microarray data analysis has been successful, while multi-class classification, such as cancer subtyping, remains challenging.

Results

We target on the challenging multi-class classification in microarray data analysis, especially on the cancer subtyping using gene expression microarray. We present a novel class discrimination strength vector to represent individual genes and introduce a new measurement to quantify the class discrimination strength difference between two genes. Such a new distance measure is employed in gene clustering, and subsequently the gene cluster information is exploited to select a set of genes which can be used to construct a sample classifier.

We tested our method on four real cancer microarray datasets each contains multiple subtypes of cancer patients. The experimental results show that the constructed classifiers all achieved a higher classification accuracy than the previously best classification results obtained on these four datasets. Additional tests show that the selected genes by our method are less correlated and they all contribute statistically significantly to the more accurate cancer subtyping.

Conclusion

The proposed novel class discrimination strength vector is a better representation than the gene expression vector, in the sense that it can be used to effectively eliminate highly correlated but redundant genes for classifier construction. Such a method can build a classifier to achieve a higher classification accuracy, which is demonstrated via cancer subtyping.
Utilization of the PICO framework to improve searching PubMed for clinical questions
Authors: Schardt Connie , Adams Martha B , Owens Thomas , Keitz Sheri , Fontelo Paul
Published: June 2007

Background

Supporting 21st century health care and the practice of evidence-based medicine (EBM) requires ubiquitous access to clinical information and to knowledge-based resources to answer clinical questions. Many questions go unanswered, however, due to lack of skills in formulating questions, crafting effective search strategies, and accessing databases to identify best levels of evidence.

Methods

This randomized trial was designed as a pilot study to measure the relevancy of search results using three different interfaces for the PubMed search system. Two of the search interfaces utilized a specific framework called PICO, which was designed to focus clinical questions and to prompt for publication type or type of question asked. The third interface was the standard PubMed interface readily available on the Web. Study subjects were recruited from interns and residents on an inpatient general medicine rotation at an academic medical center in the US. Thirty-one subjects were randomized to one of the three interfaces, given 3 clinical questions, and asked to search PubMed for a set of relevant articles that would provide an answer for each question. The success of the search results was determined by a precision score, which compared the number of relevant or gold standard articles retrieved in a result set to the total number of articles retrieved in that set.

Results

Participants using the PICO templates (Protocol A or Protocol B) had higher precision scores for each question than the participants who used Protocol C, the standard PubMed Web interface. (Question 1: A = 35%, B = 28%, C = 20%; Question 2: A = 5%, B = 6%, C = 4%; Question 3: A = 1%, B = 0%, C = 0%) 95% confidence intervals were calculated for the precision for each question using a lower boundary of zero. However, the 95% confidence limits were overlapping, suggesting no statistical difference between the groups.

Conclusion

Due to the small number of searches for each arm, this pilot study could not demonstrate a statistically significant difference between the search protocols. However there was a trend towards higher precision that needs to be investigated in a larger study to determine if PICO can improve the relevancy of search results.
Replacing the projected retiring baby boomer nursing cohort 2001 – 2026
Authors: Schofield Deborah J
Published: June 2007

Background

The nursing population in Australia is ageing. However, there is little information on the rate and timing of nursing retirement.

Methods

Specifically designed health workforce extracts from the Australian Bureau of Statistics (ABS) censuses from 1986 to 2001 are used to estimate the rate of nursing retirement. The 2001 nursing data are then "aged" and retirement of the nursing workforce projected through to 2026. ABS population projections are used to examine the future age structure of the population and the growth and age distribution of the pool of labour from which future nurses will be drawn.

Results

Attrition rates for nurses aged 45 and over are projected to be significantly higher between the base year of 2006 and 2026, than they were between 1986 and 2001 (p < 0.001).

Between 2006 and 2026 the growth in the labour force aged 20 to 64 is projected to slow from 7.5 per cent every five years to about 2 per cent, and over half of that growth will be in the 50 to 64 year age group. Over this period Australia is projected to lose almost 60 per cent of the current nursing workforce to retirement, an average of 14 per cent of the nursing workforce every five years and a total of about 90,000 nurses.

Conclusion

The next 20 years will see a large number of nursing vacancies due to retirement, with ageing already impacting on the structure of the nursing workforce. Retirement income policies are likely to be a key driver in the retirement rate of nurses, with some recent changes in Australia having some potential to slow retirement of nurses before the age of 60 years. However, if current trends continue, Australia can expect to have substantially fewer nurses than it needs in 2026.
Role of CD151, A tetraspanin, in porcine reproductive and respiratory syndrome virus infection
Authors: Shanmukhappa Kumar , Kim Jeong-Ki , Kapil Sanjay
Published: June 2007

Background

Porcine reproductive and respiratory syndrome virus (PRRSV) is a RNA virus causing respiratory and reproductive diseases in swine. The susceptibility for PRRSV varies between the different breeds of swine. In cell culture, PRRSV virus can be propagated in primary porcine alveolar macrophages and some African green monkey kidney cell lines, such as MARC-145 cells. Previous studies have shown that 3' untranslated region (UTR) RNAs of the arteriviruses play an important role in the replication of the virus through interactions with cellular proteins. To better understand the differences in the replication capability of PRRSV in different cell lines, we sought to identify the host cellular proteins interacting with PRRSV 3' UTR RNA. We constructed a cDNA library of MARC-145 cell line in lambda ZAP Express vector and screened the library with the positive sense 3' UTR RNA of PRRSV.

Results

We found that CD151, a host cellular protein, interacting with PRRSV 3' UTR RNA. The specificity of the interaction between CD151 and PRRSV 3' UTR RNA was examined by gel shift assay as well as North-Western hybridization. The transfection of CD151 expression clone into BHK-21 rendered these cells susceptible to PRRSV infection, and the transfection of siRNA against CD151 into MARC-145 significantly reduced the level of PRRSV infection. Also, anti-CD151 antibody treatment to MARC-145 completely blocked PRRSV infection.

Conclusion

Based on our results, we suggest that CD151 should cooperate in PRRSV infectionin vitroin MARC-145 and BHK-21 cells.
An oestrogen-dependent model of breast cancer created by transformation of normal human mammary epithelial cells
Authors: Duss Stephan , André Sylvie , Nicoulaz Anne-Laure , Fiche Maryse , Bonnefoi Hervé , Brisken Cathrin , Iggo Richard D
Published: June 2007

Introduction

About 70% of breast cancers express oestrogen receptor α (ESR1/ERα) and are oestrogen-dependent for growth. In contrast with the highly proliferative nature of ERα-positive tumour cells, ERα-positive cells in normal breast tissue rarely proliferate. Because ERα expression is rapidly lost when normal human mammary epithelial cells (HMECs) are grown in vitro, breast cancer models derived from HMECs are ERα-negative. Currently only tumour cell lines are available to model ERα-positive disease. To create an ERα-positive breast cancer model, we have forced normal HMECs derived from reduction mammoplasty tissue to express ERα in combination with other relevant breast cancer genes.

Methods

Candidate genes were selected based on breast cancer microarray data and cloned into lentiviral vectors. Primary HMECs prepared from reduction mammoplasty tissue were infected with lentiviral particles. Infected HMECs were characterised by Western blotting, immunofluorescence microscopy, microarray analysis, growth curves, karyotyping and SNP chip analysis. The tumorigenicity of the modified HMECs was tested after orthotopic injection into the inguinal mammary glands of NOD/SCID mice. Cells were marked with a fluorescent protein to allow visualisation in the fat pad. The growth of the graft was analysed by fluorescence microscopy of the mammary glands and pathological analysis of stained tissue sections. Oestrogen dependence of tumour growth was assessed by treatment with the oestrogen antagonist fulvestrant.

Results

Microarray analysis of ERα-positive tumours reveals that they commonly overexpress the Polycomb-group gene BMI1. Lentiviral transduction with ERα, BMI1, TERT and MYC allows primary HMECs to be expanded in vitro in an oestrogen-dependent manner. Orthotopic xenografting of these cells into the mammary glands of NOD/SCID mice results in the formation of ERα-positive tumours that metastasise to multiple organs. The cells remain wild type for TP53, diploid and genetically stable. In vivo tumour growth and in vitro proliferation of cells explanted from tumours are dependent on oestrogen.

Conclusion

We have created a genetically defined model of ERα-positive human breast cancer based on normal HMECs that has the potential to model human oestrogen-dependent breast cancer in a mouse and enables the study of mechanisms involved in tumorigenesis and metastasis.
Surfactant therapy for acute respiratory failure in children: a systematic review and meta-analysis
Authors: Duffett Mark , Choong Karen , Ng Vivian , Randolph Adrienne , Cook Deborah J
Published: June 2007

Introduction

Exogenous surfactant is used to treat acute respiratory failure in children, although the benefits and harms in this setting are not clear. The objective of the present systematic review is to assess the effect of exogenous pulmonary surfactant on all-cause mortality in children mechanically ventilated for acute respiratory failure.

Methods

We searched the MEDLINE, EMBASE, CINAHL and Ovid Healthstar databases, the bibliographies of included trials and review articles, conference proceedings and trial registries. We included prospective, randomized, controlled trials of pulmonary surfactant that enrolled intubated and mechanically ventilated children with acute respiratory failure. We excluded trials that exclusively enrolled neonates or patients with asthma. Two reviewers independently rated trials for inclusion, extracted data and assessed the methodologic quality. We quantitatively pooled the results of trials, where suitable, using a random effects model.

Results

Six trials randomizing 314 patients were included. Surfactant use reduced mortality (relative risk = 0.7, 95% confidence interval = 0.4 to 0.97, P = 0.04), was associated with increased ventilator-free days (weighted mean difference = 2.5 days, 95% confidence interval = 0.3 to 4.6 days, P = 0.02) and reduced the duration of ventilation (weighted mean difference = 2.3 days, 95% confidence interval = 0.1 to 4.4 days, P = 0.04).

Conclusion

Surfactant use decreased mortality, was associated with more ventilator-free days and reduced the duration of ventilation. No serious adverse events were reported.
Detailed analysis of 15q11-q14 sequence corrects errors and gaps in the public access sequence to fully reveal large segmental duplications at breakpoints for Prader-Willi, Angelman, and inv dup(15) syndromes
Authors: Makoff Andrew J , Flomen Rachel H
Published: June 2007

Background

Chromosome 15 contains many segmental duplications, including some at 15q11-q13 that appear to be responsible for the deletions that cause Prader-Willi and Angelman syndromes and for other genomic disorders. The current version of the human genome sequence is incomplete, with seven gaps in the proximal region of 15q, some of which are flanked by duplicated sequence. We have investigated this region by conducting a detailed examination of the sequenced genomic clones in the public database, focusing on clones from the RP11 library that originates from one individual.

Results

Our analysis has revealed assembly errors, including contig NT_078094 being in the wrong orientation, and has enabled most of the gaps between contigs to be closed. We have constructed a map in which segmental duplications are no longer interrupted by gaps and which together reveals a complex region. There are two pairs of large direct repeats that are located in regions consistent with the two classes of deletions associated with Prader-Willi and Angelman syndromes. There are also large inverted repeats that account for the formation of the observed supernumerary marker chromosomes containing two copies of the proximal end of 15q and associated with autism spectrum disorders when involving duplications of maternal origin (inv dup[15] syndrome).

Conclusion

We have produced a segmental map of 15q11-q14 that reveals several large direct and inverted repeats that are incompletely and inaccurately represented on the current human genome sequence. Some of these repeats are clearly responsible for deletions and duplications in known genomic disorders, whereas some may increase susceptibility to other disorders.
Acute alcohol activates STAT3, AP-1, and Sp-1 transcription factors via the family of Src kinases to promote IL-10 production in human monocytes
Authors: Norkina Oxana , Dolganiuc Angela , Shapiro Taryn , Kodys Karen , Mandrekar Pranoti , Szabo Gyongyi
Published: June 2007

Alcohol consumption is associated with an imbalance in pro- and anti-inflammatory cytokines and immunosuppression, partially as a result of enhanced IL-10 production. The mechanisms of IL-10 induction by alcohol remain poorly understood. We identified that increased IL-10 production in human monocytes after acute in vivo alcohol consumption or in vitro alcohol treatment was associated with increased STAT3 activation. Alcohol alone induced and in combination with LPS augmented STAT3 phosphorylation at tyrosine 705 (tyr705) and serine 727 (ser727) residues and increased STAT3 binding to DNA. Upstream, alcohol activated the Src kinases, as indicated by an increase in phosphorylated and a decrease in nonphosphorylated Src proteins. STAT3 activation by Src kinases occurred directly at the tyr705 residue and indirectly at the ser727 residue via JNK MAPKs. Using specific Src (PP2), JNK1/2 (SB600125), or p38 (SB203580) inhibitors, we determined that alcohol treatment alone induced and together with LPS, augmented the DNA-binding capacity of the specificity protein-1 (Sp-1) and AP-1 transcription factors involved in IL-10 production via Src-mediated activation of p38 MAPK and JNK, respectively. Our data suggest that acute alcohol activates Src/STAT3 and Src/MAPK/STAT3, AP-1, and Sp-1 pathways as important mechanisms for IL-10-mediated immunomodulation after acute alcohol use.
Rapid T cell receptor-mediated SHP-1 S591 phosphorylation regulates SHP-1 cellular localization and phosphatase activity
Authors: Liu Yin , Kruhlak Michael J , Hao Jian-Jiang , Shaw Stephen
Published: June 2007

Since the tyrosine phosphatase SHP-1 plays a major role in regulting T cell signaling, we investigated regulation thereof by Ser/Thr phosphorylation. We found that T cell receptor (TCR) stimulation induced fast (≤1 min) and transient phosphorylation of SHP-1 S591 in both Jurkat and human peripheral blood T-cells (PBT). Phosphorylation of S591 in T-cells could be mediated artificially by a constitutive active PKC-theta construct, but the dose dependence of inhibition by PKC inhibitors indicated that PKCs were not the relevant basophilic kinase in the physiological response. S591 phosphorylation inhibited phosphatase function since a S591D mutant had lower activity than the S591A mutant. Additional evidence that S591 phosphorylation alters SHP-1 function was provided by studies of Jurkat cells stably expressing SHP-1 wild type or mutants. In those cells, S591D mutation reduced the capacity of transfected SHP-1 to inhibit TCR-induced phosphorylation of PLC-γ1. Interestingly, SHP-1 Y536 phosphorylation (previously shown to augment phosphatase activity) was also induced in PBT by TCR signal but at a much later time compared with S591 (∼30 min). S591 phosphorylation also altered cellular distribution of SHP-1 because: 1) SHP-1 in lipid rafts and a sheared membrane fraction was hypophosphorylated; 2) In stably transfected Jurkat cell lines, S591D mutant protein had reduced presence in both lipid raft and the sheared membrane fraction; 3) S591 phosphorylation prevented nuclear localization of a C-terminal GFP tagged SHP-1 construct. Our studies also shed light on an additional mechanism regulating SHP-1 nuclear localization, namely conformational autoinhibition. These findings highlight elegant regulation of SHP-1 by sequential phosphorylation of serine then tyrosine.
Oxygen-sensitive regulatory volume increase and Na transport in red blood cells from the cane toad,Bufo marinus
Authors: Kristensen Karina , Koldkjær Pia , Berenbrink Michael , Wang Tobias
Published: June 2007

The red blood cells (RBCs) of cane toad, Bufo marinus, are only partially saturated with oxygen in most of the circulation due to cardiac shunts that cause desaturation of arterial blood. The present study examines the oxygen dependency of RBC ouabain-insensitive unidirectional Na transport,using 22Na, in control cells and in cells exposed to hyperosmotic shrinkage or the β-adrenergic agonist isoproterenol. Deoxygenation per se induced a slow, but significant Na influx, which was paralleled by a slow increase in RBC volume. Hyperosmotic shrinkage by a calculated 25% activated a robust Na influx that in the first 30 min had a strong PO2 dependency with maximal activation at low PO2 values and a P50of ∼5.5 kPa. This activation was completely abolished by the Na/H exchanger (NHE) inhibitor EIPA (10–4 mol l-1). Hyperosmotic shrinkage is particularly interesting in B. marinus as it withstands considerable elevation in extracellular osmolarity following dehydration. Parallel studies showed that deoxygenated B. marinusRBCs had a much faster regulatory volume increase (RVI) response than air-equilibrated RBCs, reflecting the difference in magnitude of Na influxes at the two PO2 values. The extent of RVI(∼60%) after 90 min, however, was similar under the two conditions,reflecting a more prolonged elevation of the shrinkage-induced Na influx in air-equilibrated RBCs. There were no significant differences in the ability to perform RVI between whole blood cells at a PCO2of 1 and 3 kPa or washed RBCs, and 10–4 mol l-1amiloride reduced the RVI under all conditions, whereas 10–5mol l-1 bumetanide had no effect. Isoproterenol(10–5 mol l-1) induced a significant and prolonged increase in an EIPA-sensitive and bumetanide-insensitive Na influx at low PO2 under iso-osmotic conditions, whilst there was no stimulation by isoproterenol for up to 45 min in air-equilibrated RBCs. The prolonged β-adrenergic activation of the Na influx at low PO2 is distinctly different from the rapid and transient stimulation in teleost RBCs, suggesting significant differences in the signal transduction pathways leading to transporter activation between vertebrate groups.
CoCl2 induces protective eventsviathe p38-MAPK signalling pathway and ANP in the perfused amphibian heart
Authors: Gaitanaki Catherine , Kalpachidou Theodora , Aggeli Ioanna-Katerina S. , Papazafiri Panagiota , Beis Isidoros
Published: June 2007

Mitogen-activated protein kinases (MAPKs) constitute one of the most important intracellular signalling pathways. In particular, the p38-MAPK subfamily is known to be activated under various stressful conditions, such as mechanical or oxidative stress. Furthermore, cobalt chloride(CoCl2) has been shown to mimic hypoxic responses in various cell lines and cause overproduction of reactive oxygen species (ROS). In the current study, we investigated the effect of CoCl2 on p38-MAPK signalling pathway in the perfused Rana ridibunda heart. Immunoblot analysis of the phosphorylated, and thus activated, form of p38-MAPK revealed that maximum phosphorylation was attained at 500 μmol l-1CoCl2. A similar profile was observed for MAPKAPK2 and Hsp27 phosphorylation (direct and indirect p38-MAPK substrates, respectively). Time course analysis of p38-MAPK phosphorylation pattern showed that the kinase reached its peak within 15 min of treatment with 500 μmol l-1CoCl2. Similar results were obtained for Hsp27 phosphorylation. In the presence of the antioxidants Trolox or Lipoic acid, p38-MAPK CoCl2-induced phosphorylation was attenuated. Analogous results were obtained for Hsp27 and MAPKAPK2. In parallel, mRNA levels of the ANP gene, a hormone whose transcriptional regulation has previously been shown to be regulated by p38-MAPK, were examined (semi-quantitative ratiometric RT-PCR). CoCl2 treatment significantly increased ANP mRNA levels,whereas, in the presence of antioxidants, the transcript levels returned to basal values. All the above data indicate that CoCl2 stimulates compensatory mechanisms involving the p38-MAPK signalling cascade along with ANP.
Electrical and behavioral courtship displays in the mormyrid fish Brienomyrus brachyistius
Authors: Wong Ryan Y. , Hopkins Carl D.
Published: June 2007

Mormyrid electric fish rely on the waveform of their electric organ discharges (EODs) for communicating species, sex, and social status, while they use the sequences of pulse intervals (SPIs) for communicating rapidly changing behavioral states and motivation. Little is known of electric signaling during courtship behavior because of two major difficulties: (1) the fish are not easily bred in captivity and (2) there is no reliable means of separating electric signals from several individuals in natural communication settings. Through simulating artificial rain conditions, we have successfully induced courtship and succeeded in breeding a mormyrid electric fish(Brienomyrus brachyistius) in the laboratory. We have also developed a system of video recording and editing combined with cross correlation analysis to precisely record and view behavior and separate EODs from two individuals in non-breeding and breeding contexts. Knowing the electrical and motor patterns during courtship allows for further exploration of topics such as mate choice and neural basis of pattern generation in these fish.

Here we describe nine common motor displays and 11 SPIs. Analysis of frequency of occurrences suggests that some SPI patterns are sex and season specific. We also observed electrical duetting called `rasp matching' during courtship signaling among pairs; males and females exchange `rasps' and`bursts', respectively, in alternation. Our study employs new techniques to separate and document SPIs in the context of courtship. We show that some SPIs correlate with specific behavioral acts around the time of spawning.
Relationship between avian growth rate and immune response depends on food availability
Authors: Brzęk Pawel , Konarzewski Marek
Published: June 2007

Life history theory predicts that when resources are limited growing organisms are likely to trade an immune response for competing demands of growth. To test this we examined the effect of energy intake on body mass increments and an immune response in hand-reared sand martin (Riparia riparia) nestlings. We subjected the nestlings to three different feeding regimes, mimicking the range of food availability in the wild, and then evaluated nestlings' immune response to phytohaemagglutinin (PHA). Direction of correlation between the magnitude of PHA-induced swelling response and body mass increments depended on food availability: it was negative when food was scarce and positive when resources were plentiful. There was no significant correlation between the two traits under intermediate feeding conditions. We conclude that the relative cost of immune function in young birds depends on food availability and, therefore, may be modified by external factors such as weather conditions or hatching asynchrony.
Mechanosensation and mechanical load modulate the locomotory gait of swimmingC. elegans
Authors: Korta Jeremie , Clark Damon A. , Gabel Christopher V. , Mahadevan L. , Samuel Aravinthan D. T.
Published: June 2007

Animals move through their environments by selecting gaits that are adapted to the physical nature of their surroundings. The nematode Caenorhabditis elegans swims through fluids or crawls on surfaces by propagating flexural waves along its slender body and offers a unique opportunity for detailed analysis of locomotory gait at multiple levels including kinematics,biomechanics and the molecular and physiological operation of sensory and motor systems. Here, we study the swimming gait of C. elegans in viscous fluids in the range 0.05-50 Pa s. We find that the spatial form of the swimming gait does not vary across this range of viscosities and that the temporal frequency of the swimming gait only decreases by about 20% with every 10-fold increase in viscosity. Thus, C. elegans swims in low gear,such that its musculature can deliver mechanical force and power nearly 1000-fold higher than it delivers when swimming in water. We find that mutations that disrupt mechanosensation, or the laser killing of specific touch receptor neurons, increase the temporal frequency of the undulating gait, revealing a novel effect of mechanosensory input in regulating the putative central pattern generator that produces locomotion. The adaptability of locomotory gait in C. elegans may be encoded in sensory and motor systems that allow the worm to respond to its own movement in different physical surroundings.
The magnetic compass of domestic chickens,Gallus gallus
Authors: Wiltschko Wolfgang , Freire Rafael , Munro Ursula , Ritz Thorsten , Rogers Lesley , Thalau Peter , Wiltschko Roswitha
Published: June 2007

By directional training, young domestic chickens have been shown to use a magnetic compass; the same method has now been used to analyse the functional characteristics and the physical principles underlying the chickens' magnetic compass. Tests in magnetic fields with different intensities revealed a functional window around the intensity of the local geomagnetic field, with this window extending further towards lower than higher intensities. Testing chickens under monochromatic 465 nm blue and 645 nm red light suggested a wavelength dependence, with orientation possible under blue but not under red light. Exposing chickens to an oscillating field of 1.566 MHz led to disorientation, identifying an underlying radical pair mechanism. Local anesthesia of the upper beak, where iron-rich structures have been described as potential magnetoreceptors, did not affect the performance, suggesting that these receptors are not involved in compass orientation. These findings show obvious parallels to the magnetic compass described for European robins,indicating that chickens and small passerines use the same type of magnetic compass mechanism. This suggests that the avian magnetic compass may have evolved in the common ancestor of all present-day birds to facilitate orientation within the home range.
The effect of insect surface features on the adhesion of viscous capture threads spun by orb-weaving spiders
Authors: Opell Brent D. , Schwend Harold S.
Published: June 2007

Spider orb-webs intercept a broad range of insects and their capture threads must adhere to a range of surface textures. In species of the Araneoidea clade, these capture threads are composed of viscid droplets whose size and spacing differ among species. To determine how droplet profile and insect surface texture interact, we measured the stickiness of viscous threads produced by four species using four insect surfaces that ranged from a smooth beetle elytra to the dorsal surface of a fly abdomen that was covered by large, widely spaced setae. The adhesion of threads to these surfaces differed by as much as 3.5-fold within a spider species and 2.1-fold for the same insect surface between spider species. However, 96% of these differences in stickiness was explained by four variables: the ratio of natural log of droplet volume to setal length, the natural log of droplet volume per mm of thread length, setal surface area, and the area of cuticle not excluded from thread contact by setae. Compared with previous measurements of primitive cribellar capture threads produced by orb weavers of the Deinopoidea clade,viscous threads performed more uniformly over the range of insect surfaces. They also held bug hemelytra, which were densely covered with fine setae, more securely, but held beetle elytra, fly wings and fly abdomens less securely than did viscous threads. Hemelytra may be held more securely because their setae more easily penetrate the viscous boundary layer to establish a greater area of interaction and, after having done so, offer more resistance as they are pulled through this layer. Finely textured surfaces may also have higher effective surface energies and therefore may interact more completely with viscous material.
Energetic cost of producing cyclic muscle force, rather than work, to swing the human leg
Authors: Doke Jiro , Kuo Arthur D.
Published: June 2007

We compared two hypothesized energetic costs for swinging the human leg quickly. The first cost is to perform mechanical work on the leg, and the second is to produce muscle force cyclically at high frequencies. Substantial metabolic energy is expended to perform isolated leg swinging, especially at rates greater than the leg's natural pendular frequency. To determine whether the production of muscle force contributes to this cost, we measured oxygen consumption in human subjects (N=6) performing isolated swinging of the leg at frequencies 0.7-1.1 Hz. Amplitude of swing was varied as a function of frequency so that the rate of positive mechanical work performed on the leg remained fixed. We expected that the cost of producing force would increase,in contrast to the cost of performing work. The results showed that average rate of positive mechanical work performed on the leg remained nearly constant as a function of frequency, at 0.073±0.014 W kg-1. Net metabolic rate, however, increased by 53%, from 0.66 W kg-1 to 1.01 W kg-1. Work may be performed on the leg and with a proportional metabolic cost, but it cannot explain the substantial increases observed here. Metabolic energy expenditure appears to increase in proportion with muscle force or torque, and in inverse proportion to duration of force. This energetic cost may be associated with cyclical calcium transport, where rate-limiting of crossbridge attachments may require greater sarcoplasmic calcium concentration at high frequencies of leg swinging to produce the same amplitude of muscle force. It may also be relevant to moving the legs back and forth relative to the body during walking.
Examples of in-cylinder velocity measurements for internal combustion engines
Authors: Farrell P V
Published: June 2007

This paper will provide a brief overview of some current efforts in in-cylinder velocity measurements for internal combustion engines. This is a very active field and has been for over 30 years. New technologies enable measurements not possible years ago; yet some challenges in acquiring and interpreting experimental velocity results remain. This paper will try to outline some recent results and in particular will give a little more detail for three example measurements.
Two-phase fuel distribution measurements in a gasoline direct injection engine with an air-assisted injector using advanced optical diagnostics
Authors: Leach B , Zhao H , Li Y , Ma T
Published: June 2007

The fuel distribution and mixture formation processes within an internal combustion (IC) engine can greatly affect its ignition, combustion, pollutant formation, and fuel consumption. For more than two decades the laser-induced fluorescence (LIF) technique has been successfully applied to the study of mixture formation and distribution. However, in a gasoline direct injection (GDI) engine the fuel may exist in either the liquid or vapour phase, and it is therefore advantageous to be able to observe both phases simultaneously.

One means of achieving this is the laser-induced exciplex fluorescence (LIEF) technique. This paper details its application to a single-cylinder GDI engine equipped with an air-assisted fuel injection system and full optical access. Naphthalene and N, N-dimethlylaniline (DMA) tracers were used to track the fuel and were excited using the expanded beam from an XeCl excimer laser at 308 nm. An image doubler and optical filtering system was used to collect the images that were recorded from the front of the cylinder. Early and late injection timings were investigated, and the spray characteristics and mixture formation from the two strategies were found to differ considerably.

In order to investigate the effect of absorption on the fluorescence signal, the beam was introduced into the cylinder from three directions. Crank angle resolved results, from the start of injection to the end of the compression stroke, are presented, with an image for each illumination direction and injection timing.
Hypokalaemia following paracetamol overdose in two teenage girls
Authors: Godber Ian M , Jarvis Sarah J , Maguire Donogh
Published: June 2007

We report on two teenage girls presenting following significant paracetamol overdoses (>28 g paracetamol). Both presented within 4 h of the overdose and both were treated with N-acetylcysteine, in accordance with the National Poisons Information Service protocol. Within 8 h of presentation both had developed significant hypokalaemia with serum potassium concentrations <3.0 mmol/L and were treated with intravenous potassium chloride. Potassium concentrations returned to within reference limits (>3.5 mmol/L) after commencing potassium chloride supplementation. An audit of potassium concentrations in 254 patients presenting with significant paracetamol overdose (paracetamol >0.5 mmol/L) admitted through four A&E departments in the West of Scotland showed a significant decline in mean serum potassium from 3.9 mmol/L on admission to 3.6 mmol/L ( P = <0.001) over the next 36 h. The mechanism for this hypokalaemia in these two individuals is unclear, however regular monitoring of potassium is advocated in such patients during their initial treatment.
Liquorice and soy sauce, a life-saving concoction in a patient with Addison's disease
Authors: Cooper H , Bhattacharya B , Verma V , McCulloch A J , Smellie W S A , Heald A H
Published: June 2007

Addison's disease is a relatively common disorder to endocrinologists, but is rare and potentially fatal when presenting acutely. Treatment now involves replacement of glucocorticoids and mineralocorticoids with synthetic compounds, although historically patients took common salt and plant-based preparations. We describe the case of a 42-year-old woman who self-treated undiagnosed Addison's disease for several years with soy sauce and liquorice sticks. She presented with a four-week history of decreased energy, malaise and postural dizziness. Our patient described an unusual diet of liquorice sticks and soy sauce, consuming around 46 g of salt per week. There was a family history of Type 1 diabetes mellitus. Physical examination was unremarkable, although subsequent investigation confirmed Addison's disease. Liquorice provided glycyrrhizic acid and glycyrrhetinic acid, which act on 11-beta hydroxysteroid dehydrogenase enzymes. In this case, the net effect was potentiation of glucocorticoid action on renal mineralocorticoid receptors in the context of failing adrenocortical steroid production. The case highlights the importance of taking a dietary history to aid diagnosis.
Quantitation of urinary glycosaminoglycans using dimethylene blue as a screening technique for the diagnosis of mucopolysaccharidoses - an evaluation
Authors: Gray George , Claridge Paul , Jenkinson Linda , Green Anne
Published: June 2007

Background: The mucopolysaccharidoses (MPSs) are a group of inherited disorders due to defects in lysosomal enzymes catalysing the breakdown of glycosaminoglycans (GAGs). Usually they are detected using techniques to separate the accumulating GAGs in urine. However more recently an improved dye-based method measuring total urine GAG concentrations has become available. We have evaluated this method in the context of its application as a general screening technique in a routine metabolic laboratory.

Method: An automated method for the quantitation of urinary GAGs using dimethylene blue was developed on a Cobas Fara analyser and evaluated in terms of its specificity, sensitivity and value in the diagnosis of the MPSs. The test was applied to 6156 anonymized urine samples received for tests for inherited metabolic diseases and to 121 samples from 85 patients with a variety of proven MPSs.

Results: A substantial number of samples from unaffected individuals gave abnormal results while a significant number of samples from patients with MPSs gave results within normal limits.

Conclusion: In the context of our laboratory, it was not appropriate for use as a screening technique when applied to all specimens received for metabolic tests or as a first-line screening test for samples where mucopolysaccharide analysis was requested. However it was retained and used in parallel with cellulose acetate electrophoresis to aid interpretation.
Parkinson's disease: the effect of L-dopa therapy on urinary free catecholamines and metabolites
Authors: Davidson D F , Grosset K , Grosset D
Published: June 2007

Background: L-dopa is an important antiparkinsonian drug. It is a precursor of dopamine and the other catecholamines. Potentially, administration of L-dopa could lead to increased urinary excretion of catecholamines and their metabolites to abnormal amounts. The current study aimed to determine these excretions in patients with Parkinson's disease (PD) receiving L-dopa compared with suitable controls. This is the first assessment of the effect of exogenous administration of L-dopa on urinary free metadrenalines.

Methods: Using one-way analysis of variance (ANOVA), urine catecholamines and metabolites, expressed as mmol per mole creatinine, were compared in: patients with PD who were receiving L-dopa; patients with PD but not receiving L-dopa; and patients without PD who were being investigated for the presence of phaechromocytoma but were found not to have the disease.

Results: Significantly higher values for urinary dopamine, homovanillic acid, free normetadrenaline and free metadrenaline were found in patients with PD receiving L-dopa compared with the other two control groups. In all the patients with PD, these four analytes were significantly correlated with daily dose of L-dopa.

Conclusion: L-dopa therapy can result in production of false positives for urinary excretion of dopamine, homovanillic acid, free normetadrenaline or free metadrenaline and thereby decrease the diagnostic value of these measurements in identifying phaeochromocytoma and related tumours.