bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing therapy for myeloid disorders of Down syndrome
Authors: Webb David K. H.
Published: September 2005

Children with Down syndrome (DS) are at increased risk of leukaemia. Myeloid disorders include transient abnormal myelopoiesis (TAM), myelodysplasia (MDS) and acute myeloid leukaemia (AML). Mutations in the GATA‐1 gene, which encodes for a transcription factor central to the normal development of the erythroid and megakaryocytic lineages, are found in cases of TAM, MDS and AML in DS children. DS children with MDS/AML mostly present between the ages of 1 and 4 years, and have a large predominance of megakaryoblastic disease (French–American–British type M7). The MDS and AML are part of a single disease entity (myeloid leukaemia of Down syndrome) that is extremely sensitive to chemotherapy. Resistant disease and relapse are rare, but treatment‐related toxicity is high, and deaths in remission have exceeded those due to disease in most series. Accordingly, controlled dosage reduction is the focus of contemporary treatment studies.
Central nervous system‐directed preventative therapy in adults with lymphoma
Authors: McMillan Andrew
Published: September 2005

All adult patients with Burkitt lymphoma or lymphoblastic lymphoma should receive central nervous system (CNS)‐directed therapy with both intrathecal and high‐dose systemic chemotherapy. There is no evidence to support the routine use of prophylactic CNS‐directed therapy in any specific subgroup of adult patients with ‘low grade’ lymphomas. There are some anatomical sites where involvement by lymphoma is associated with a higher risk of CNS relapse. These probably include testis, breast, paranasal sinuses and the epidural space. Multivariate analyses strongly support a raised serum lactate dehydrogenase level and the involvement of more than one extranodal site as the strongest predictors of subsequent CNS relapse. A high International Prognostic Index score may replace the use of the above two factors in combination. There is evidence of good efficacy when intrathecal chemotherapy and high‐dose systemic chemotherapy are used in combination. It is not clear how the best balance between the ‘sensitivity’ and ‘specificity’ of the choice of patients to receive CNS‐directed therapy can be achieved.
Does severity of low‐dose, double‐blind, placebo‐controlled food challenges reflect severity of allergic reactions to peanut in the community?
Authors: Hourihane J. O'B. , Grimshaw K. E. C. , Lewis S. A. , Briggs R. A. , Trewin J. B. , King R. M. , Kilburn S. A. , Warner J. O.
Published: September 2005

Background
The severity of allergic reactions to food appears to be affected by many interacting factors. It is uncertain whether challenge‐based reactions reflect the severity of past reactions or can predict future risk.

Objective
To explore the relationship of a subject's clinical history of past reactions to the severity of reaction elicited by a low‐dose, double‐blind, placebo‐controlled food challenge (DBPCFC) with peanut.

Method
Cross‐sectional questionnaire assessment of community‐based allergic reactions and low‐dose DBPCFC in self‐selected peanut‐allergic subjects. Reaction severity was assessed using a novel scoring system, taking account of the dose of allergen ingested.

Results
Forty subjects (15 males, 23 children, 23 asthmatics by history) were studied. Only the most recent community reaction predicted the severity of reaction in the DBPCFC, but even this association was weak (r=0.37, P=0.03). Peanut‐specific IgE (PsIgE) and skin prick test (SPT) weal size were not associated with community score but PsIgE level correlated well with the challenge score (r=0.6, P=0.001). Asthma did not affect the eliciting dose or challenge score directly but the association of PsIgE and challenge score was stronger in those without asthma (r=0.72, P=0.001) than in those with asthma (r=0.48, P=0.02).

Conclusions
The scoring system developed appears to improve the sensitivity of assessment of reactions induced by DBPCFC. This is the first prospective study showing an association between PsIgE levels and clinical reactivity in DBPCFC, an effect that is more pronounced in non‐asthmatics. This finding has important implications for the clinical care of subjects with food allergy. There is a poor correlation between the severity of reported reactions in the community and the severity of reaction elicited during low‐dose DBPCFC with peanut.
Effects of glutathione S‐transferase M1, T1 and P1 on lung function in asthmatic families
Authors: Carroll W. D. , Lenney W. , Jones P. W. , Strange R. C. , Child F. , Whyte M. K. , Primhak R. A. , Fryer A. A.
Published: September 2005

Rationale
Previous data have suggested that glutathione‐S‐transferase (GST) genotypes are important in determining the rate of lung function growth in childhood. This effect was most marked in Caucasian children with asthma.

Objectives
We investigated the association of lung function with GSTM1, GSTP1 and GSTT1 genotypes in Caucasian families with asthma.

Methods
Four hundred and eighteen children and 316 parents from 224 Caucasian families were recruited via a child with asthma, the proband. Associations between lung function and GST genotype were determined using multilevel models.

Results
There were no observed associations between lung function and GST genotype in parents. However, in the children, the GSTP1 val105/val105 and GSTM1 null genotypes were associated with significantly higher forced expiratory volume in 1 s (FEV1) and FVC values as percentage of predicted. This effect was not statistically significant in the probands but was marked in their siblings in whom GSTP1 val105/val105 was associated with 9.4% higher FEV1 and 10.7% higher FVC (P=0.005 and 0.001, respectively). The GSTM1 null genotype was associated with a 6.7% higher FEV1 and 4.1% higher FVC (P=0.003 and 0.063, respectively). These effects remained significant after correcting for the confounders of individual atopic status, tobacco smoke exposure and familial aggregation of lung function values.

Conclusions
GSTM1 and GSTP1 genotypes are important determinants of lung function in childhood. The smaller differences seen in probands are predicted by a simple model in which more rapid decline in lung function is seen in these individuals.
The use of exhaled nitric oxide concentration to identify eosinophilic airway inflammation: an observational study in adults with asthma
Authors: Berry M. A. , Shaw D. E. , Green R. H. , Brightling C. E. , Wardlaw A. J. , Pavord I. D.
Published: September 2005

Background
Assessment of eosinophilic airway inflammation may be helpful in the management of asthma. Nitric oxide (NO) has potential advantages as a tool to monitor airway inflammation although little is known about the relationship between NO and eosinophilic airway inflammation and the factors which influence it.

Methods
We set out to define the relationship between exhaled NO and the sputum eosinophil count, identify the exhaled NO concentration that best identified a sputum eosinophil count >3% and investigate the impact of several potential confounding factors in 566 consecutive patients with varying severity of asthma. Finally we examined the ability of exhaled NO concentrations measured at differing exhalation flows to identify the presence of a sputum eosinophilia.

Results
We found a significant positive relationship between exhaled NO and sputum eosinophil count (R2=0.26, P<0.001) which was best described using a non‐linear model. There were no clinically important confounding factors to this model. In non‐smokers an exhaled NO concentration of >8.3 p.p.b. at 250 mL/s gave 71% sensitivity and 72% specificity for identifying a sputum eosinophil count of >3%.

Conclusions
This value of exhaled NO would seem to be the best for identifying significant eosinophilic airway inflammation. It is applicable to a wide range of non‐smoking patients with asthma; exhalation flow does not alter the ability of exhaled NO concentration to detect a sputum eosinophilia.
Intestinal microbiota and immunoglobulin E responses in 5‐year‐old Estonian children
Authors: Sepp E. , Julge K. , Mikelsaar M. , Björkstén B.
Published: September 2005

Background
Over the last few decades, several studies from different parts of the world have indicated an increasing prevalence of allergic diseases. This has been related to environmental factors, like changes of microbial pressure. Our previous studies have demonstrated differences in the intestinal microbiota between allergic and non‐allergic children.

Aim
To test the hypothesis that the intestinal microbiota and IgE response are related, both in allergic and non‐allergic 5‐year‐old Estonian children.

Methods
The study group comprised 19 allergic and 19 non‐allergic 5‐year‐old children, selected from a larger group who had been followed from birth. The diagnosis of allergy was based on clinical examination of the children and on data obtained from the questionnaires. The faecal microbiota were quantified by seeding serial dilutions on nine different media for incubation in different environment. The composition of the gut microbiota was expressed both as absolute counts of the various species and their relative share among the total counts of identified microbiota.

Results
Bifidobacteria were less commonly detected in children with allergic diseases than in healthy children and clostridia comprised a higher proportion among their gut microbes. Children with specific IgE antibodies to defined allergens had higher counts of clostridia and the counts of clostridia correlated with the level of serum IgE, but only so in allergic children. In non‐allergic children, the serum IgE levels showed a positive correlation with the counts of bacteroides.

Conclusion
The development of allergic diseases seems to be associated with the composition of the gut microbial ecosystem. High counts of potential pathogens, such as clostridia, are associated with clinical manifestations of allergy and IgE antibody formation.
Diagnosing immediate reactions to cephalosporins
Authors: Romano A. , Guéant‐Rodriguez R.‐M. , Viola M. , Amoghly F. , Gaeta F. , Nicolas J.‐P. , Guéant J.‐L.
Published: September 2005

BackgroundAfter penicillins, cephalosporins are the betalactams that most often induce IgE‐mediated reactions. The development of diagnostic tests has been delayed, however, because the cephalosporin allergenic determinants have not been properly identified.

ObjectiveTo evaluate the usefulness of skin tests, serum specific IgE assays, and challenges in diagnosing immediate reactions to cephalosporins and to clarify the pathogenic mechanism of such reactions.

MethodsWe studied 76 adults with immediate reactions to cephalosporins, mainly ceftriaxone, cefotaxime, and ceftazidime. Skin tests and serum specific IgE assays were performed for culprit cephalosporins and cefaclor, as well as for penicillin, amoxicillin, and ampicillin. Some subjects with negative results underwent challenges and re‐evaluations. Responses to cephalosporins other than the culprit ones were also studied.

ResultsIn the first allergologic work‐up, an IgE‐mediated hypersensitivity to penicillins and/or cephalosporins was diagnosed in 63 (82.9%) of the 76 patients on the basis of skin‐test and/or specific IgE assay positivity. Of the 13 negative patients, eight accepted challenges and underwent re‐evaluations. Considering both first‐ and second‐evaluation results, the skin‐test‐positivity rate increased from 76.3% to 85.5% and that of sepharose‐radioimmunoassay positivity from 67.1% to 74.3%. Overall, an IgE‐mediated hypersensitivity was diagnosed in 70 patients (in seven after retesting). On the basis of skin‐test and CAP‐FEIA results, we classified our 76 patients into five groups: group A (three patients), positive only to penicillin reagents; B (17), positive to both cephalosporin and penicillin reagents; C (24), positive to more than one cephalosporin; D (21), positive only to the responsible cephalosporin; E (11) negative to skin tests and CAP‐FEIA, including five sepharose‐radioimmunoassay positive.

ConclusionsMost immediate reactions to cephalosporins appear to be IgE‐mediated. Cephalosporin skin testing and sepharose‐radioimmunoassay are useful tools for evaluating these reactions. Cephalosporin IgE‐mediated hypersensitivity may be a transient condition; therefore, allergologic exams should be repeated in patients with negative initial allergologic work‐ups, including challenges.
Effect of salbutamol on nasal symptoms and mast cell degranulation induced by adenosine 5′ monophosphate nasal challenge
Authors: Russo C. , Zeng D. , Prosperini G. , Spicuzza L. , Guarino F. , Polosa R.
Published: September 2005

Background
In addition to its well‐known functional agonism at the level of β2 adrenergic receptors on airways smooth muscle cells, salbutamol appears to have additional protective effects, possibly through an inhibition of mast cell activation.

Objective
The aim of this study is to provide the first evidence in vivo of inhibition of human mast cell activation by salbutamol.

Methods
Nine atopic subjects received placebo and salbutamol (5 mg/mL) 15 min before an adenosine 5′ monophosphate (AMP) nasal provocation in a double‐blind crossover study design. The nasal lavage was collected from these subjects prior to or 3, 5, 15 or 30 min after the AMP nasal challenge, and concentrations of histamine and tryptase in the nasal lavage were measured.

Results
AMP nasal provocation produced considerable sneezing and induced a transient increase in histamine and tryptase release with peak values achieved at 3 min after the challenge in all the subjects studied. Compared with placebo, salbutamol significantly attenuated the release of histamine and tryptase induced by AMP challenge (P=0.048 and 0.020, respectively). Moreover, the AMP‐induced sneezing was also inhibited by pre‐treatment with salbutamol (P=0.004).

Conclusions
Intranasal salbutamol attenuates nasal symptoms and inhibits histamine and tryptase release caused by AMP nasal provocation thus supporting the hypothesis that salbutamol may play an additional protective role in the airways by inhibiting mast cell activation.
Association between bronchodilating response to short‐acting β‐agonist and non‐synonymous single‐nucleotide polymorphisms of β2‐adrenoceptor gene
Authors: Cho S.‐H. , Oh S.‐Y. , Bahn J.‐W. , Choi J.‐Y. , Chang Y.‐S. , Kim Y.‐K. , Min K.‐U. , Kim Y.‐Y.
Published: September 2005

Background
With β‐agonists being the most widely used agents in the treatment of asthma, in vitro studies reported that β2‐adrenergic receptor (ADRB2) polymorphisms are associated with agonist‐promoted down‐regulation.

Objective
The present population‐based study aimed to evaluate the association between bronchodilating response to inhaled short‐acting β‐agonist and two non‐synonymous single‐nucleotide polymorphisms (SNPs) of ADRB2 (ADRB2‐16 and ADRB2‐27).

Methods
Two hundred and nine children with reduction in forced expiratory volume in 1 s of more than 20% on methacholine bronchial challenge underwent bronchodilating response testing 5 min after the inhalation of 200 μg of albuterol. Of these 209, 195 gave peripheral blood for genotyping of ADRB2 polymorphisms.

Results
The bronchodilating response was significantly higher in subjects with the homozygous Arg16 than in those with the homozygous Gly16. It was further demonstrated that haplotype pairs of the homozygous Arg16Gln27 and of the heterozygous Arg16Gln27/Gly16Glu27 showed the highest bronchodilating responses, and the haplotype pairs of the homozygous Gly16Gln27 the lowest response. As a whole, the bronchodilating response was more positively associated with the combined quantity of Arg16 and Glu27 polymorphisms than with that of Arg16 alone.

Conclusion
Non‐synonymous SNPs of ADRB2 at codons 16 and 27 is significantly associated with bronchodilating response to inhaled short acting β‐agonists.
l‐Selectin expression on neutrophils from allergic patients
Authors: Monteseirín J. , Chacón P. , Vega A. , Sánchez‐Monteseirín H. , Asturias J. A. , Martínez A. , Guardia P. , Pérez‐Cano R. , Conde J.
Published: September 2005

Background
L‐selectin (CD62L) is an adhesion molecule involved in leucocyte attachment to endothelium at sites of inflammation, and it has been demonstrated that L‐selectin is rapidly shed after neutrophil activation. Recently, it has been reported that there is increasing evidence of neutrophil participation in asthma and the allergic process.

Objective
The present study was designed to determine whether an IgE‐dependent mechanism can modulate L‐selectin expression on the surface of neutrophils. Moreover, we analyse the potential implication of intracellular signal‐transduction pathways and whether specific immunotherapy (IT), glucocorticoids and antihistamines might regulate this process.

Methods
Peripheral blood neutrophils from three groups of donors (asthmatic group without IT treatment, IT‐treated asthmatic group and healthy group) were used. Cells were challenged in vitro with the specific allergen that produced clinical symptoms in asthmatic patients and also with the allergen to which the patients were not sensitive. Neutrophils from healthy donors were also challenged with allergens. Expression of CD62L on the neutrophil surface was analysed by flow cytometry, and soluble CD62L (sCD62L) in culture supernatant by ELISA. In an attempt to discover which IgE receptor is involved, we also challenged the neutrophils with monoclonal antibody to FcɛRI, FcɛRII (CD23) and galectin‐3 receptors.

Results
When neutrophils from allergic patients were challenged with specific allergens that produce clinical allergy symptoms, L‐selectin was down‐regulated from the surface of those cells, accompanied by a concomitant up‐regulation of soluble L‐selectin in the supernatant. The challenge with antibodies against FCɛRI, FCɛRII (CD23) and galectin‐3, induces down‐modulation of L‐selectin on the surface of the neutrophils in all three cases. Calphostin C, wortmannin and manoalide attenuated CD62L down‐regulation, suggesting the potential implication of protein kinase C, phosphatidylinositol 3‐kinase and phospholipase A2 in the process. IT and glucocorticoids modulated allergen‐dependent CD62L down‐regulation, whereas antihistamines (terfenadine, loratadine and cetirizine) or nedocromil sodium did not affect the shedding of L‐selectin.

Conclusions
We present evidence that the neutrophil surface expression of CD62L can be modulated by an allergen‐dependent mechanism. The modulation of CD62L expression can be induced through the three receptors of IgE. This process can be affected by IT.
Dendritic cells in asthma: a function beyond sensitization
Authors: Van Rijt L. S. , Lambrecht B. N.
Published: September 2005

Allergic asthma is one of the most common chronic diseases in western society, characterized by variable airway obstruction, mucus hypersecretion and infiltration of the airway wall with T‐helper type 2 (Th2) cells, eosinophils and mast cells. If we are to devise new causal therapies for this disease, it is important to elucidate how Th2 cells are activated and respond to intrinsically harmless allergens. Dendritic cells (DCs) are the most important antigen‐presenting cells in the lung and are mainly recognized for their exceptional potential to generate a primary immune response and sensitization to aeroallergens. Much less attention has been paid to the role of DCs in established inflammation. Based on functional studies in a murine model for asthma, in this review article, we propose that DCs are essential for generating allergen‐specific effector Th2 responses in ongoing inflammation in sensitized mice. A better understanding of the role of DCs in the maintenance of the inflammatory response to allergens in asthma should lead to new therapeutic approaches intervening at the top of the inflammatory cascade.
Increased interferon‐γ‐ and interleukin‐4‐synthesizing subsets of circulating T lymphocytes in pregnant asthmatics
Authors: Tamási L. , Bohács A. , Pállinger É. , Falus A. , Rigó J. , Müller V. , Komlósi Z. , Magyar P. , Losonczy G.
Published: September 2005

Background
Pregnancy frequently interferes with the course of bronchial asthma, and asthmatic pregnant women experience less successful pregnancies. T lymphocytes synthesizing IL‐4 or IFN‐γ are important in allergic mechanisms of the airways as well as in materno‐fetal immunity.

Objective
We hypothesized that pregnancy (a T helper‐2 polarized state) of asthmatics will enhance the number of circulating T2 lymphocytes, but decrease the subset‐producing IFN‐γ (T1 lymphocytes) and thereby cause a culminating T2 dominance with possible clinical consequences.

Methods
IL‐4‐ or IFN‐γ‐producing T lymphocytes were determined by flow cytometry in healthy (n=8) and asthmatic (n=13) non‐pregnant women and healthy (n=18) and asthmatic (n=48) pregnant women of similar chronological and gestational (2nd–3rd trimester) age and asthma severity (Global Initiative for Asthma II–III).

Results
In the blood of non‐pregnant women – healthy or asthmatic – the numbers of IL‐4‐ and IFN‐γ+ T cells were very low (<10/μL blood). In contrast, in asthmatic pregnant women, the cell counts were 182±27 and 39±6 for IFN‐γ+ and IL‐4+ T cells/μL blood, respectively (both P<0.05 vs. respective control values of non‐pregnant asthmatics). Within the asthmatic pregnant group, significant negative correlations were revealed between the numbers of IFN‐γ+ or IL‐4+ T cells and maternal peak expiratory flow as well as birth weight of newborns (both P<0.05).

Conclusion
These data show a previously unknown immunological interference between asthma and pregnancy. The culminating proliferation of IFN‐γ+ and IL‐4+ T lymphocytes may potentially impair maternal airway symptoms as well as fetal development.
Cysteinyl leukotrienes induce monocyte chemoattractant protein 1 in human monocytes/macrophages
Authors: Ichiyama T. , Hasegawa M. , Ueno Y. , Makata H. , Matsubara T. , Furukawa S.
Published: September 2005

Background
Monocytes/macrophages have a cysteinyl leukotriene 1 (CysLT1) receptor, but its function is poorly understood.

Objective
To elucidate the biological function of the CysLT1 receptor of human monocytes/macrophages.

Methods
We examined the production of TNF‐α, IL‐1β, IL‐2, IL‐4, IL‐6, IL‐8, IL‐10, monocyte chemoattractant protein 1 (MCP‐1), macrophage colony‐stimulating factor (M‐CSF), and eotaxin induced by CysLTs (leukotriene (LT)C4, ‐D4, and ‐E4) in THP‐1 cells, a human monocytic leukaemia cell line, and peripheral blood CD14+ monocytes/macrophages. Moreover, we examined the effect of CysLTs on the expression of β‐chemokine receptor 2B (CCR2B) as the receptor of MCP‐1 by Western blot analysis.

Results
ELISA revealed that CysLTs induced MCP‐1 in THP‐1 cells and peripheral blood CD14+ monocytes/macrophages, but not other cytokines. PCR demonstrated that CysLTs increased MCP‐1 mRNA expression in THP‐1 cells, and Western blotting showed that CysLTs increased the expression of CCR2B in THP‐1 cells. Moreover, we demonstrated that pranlukast, a CysLT1 receptor antagonist, blocked MCP‐1 production by CysLTs in THP‐1 cells almost completely, and partially inhibited MCP‐1 release by CysLTs in peripheral blood CD14+ monocytes/macrophages and CCR2B expression by CysLTs in THP‐1 cells.

Conclusion
CysLTs induce MCP‐1 and increase CCR2B expression in human monocytes/macrophages.
Inflammatory mediators in exhaled breath, induced sputum and saliva
Authors: Simpson J. L. , Wood L. G. , Gibson P. G.
Published: September 2005

Background and Objective
Airway inflammation is assessed to monitor progression, control and treatment of asthma. The collection of exhaled breath condensate (EBC) provides a non‐invasive alternative to induced sputum samples for the monitoring of airway inflammation. Both samples can be confounded by salivary contamination. The aim of this study was to compare the levels of inflammatory mediators in samples of EBC, induced sputum and saliva samples from subjects with asthma.

Method
EBC, saliva and induced sputum samples were collected from subjects with asthma (n=10). Total protein, IL‐8, 8‐isoprostane and surfactant protein A (SPA) were assessed in each sample.

Results
Total protein, IL‐8, 8‐isoprostane and SPA were detected in all sputum samples. Only total protein and SPA were consistently measured in EBC, with levels at least 100‐fold lower than those measured in induced sputum. In saliva, total protein, SPA and 8‐isoprostane were detected in all samples, with IL‐8 detected in 60% of samples.

Conclusions
Induced sputum is a reliable technique that can be used to assess markers of airway inflammation. While EBC is a simple and inexpensive technique to collect lower airway secretions, the detection of inflammatory mediators is variable, and further work is required to validate this technique to assess inflammatory mediators.
Perinatal characteristics and obstetric complications as risk factors for asthma, allergy and eczema at the age of 6 years
Authors: Bernsen R. M. D. , De Jongste J. C. , Koes B. W. , Aardoom H. A. , Van Der Wouden J. C.
Published: September 2005

Background
Considerable effort has been put into identifying early determinants for atopic disorders. Many studies have evaluated the role of fetal development and obstetric complications. However, the results are not unequivocal.

Study objective
To assess the relationship between perinatal characteristics and obstetric complications, and the presence of reported current asthma, allergy and eczema at the age of 6 years in the framework of a previously conducted study.

Method
Seven hundred families in the Netherlands with index children born in 1988–1990 were retrospectively selected. Data were extracted from the Municipal Health Service's records of health examinations of these children and their siblings. These examinations were carried out at the age of 6 years. The records contained data on reported atopic disorders and perinatal characteristics.

Results
Gestational age was inversely related to the risk of asthma (P for trend: 0.03). Children with low birth weight tended to have a lower risk of any allergy, albeit not significant (P=0.07). However, no link was found between neonatal head circumference and atopic disorders. The ratio of neonatal head circumference to birth weight was positively associated with the risk of atopic disorders, especially with the risk of asthma (odds ratio (OR)=1.87; 95% confidence interval (CI95%)=[1.11, 3.15]).

Vacuum extraction was a risk factor for allergy (OR=1.84, CI95%=[1.03, 3.28]), but not for asthma. Induced labour was positively associated with the risk of inhalant allergy (OR=2.22, CI95%=[1.09, 4.51]) and, to a lesser extent, asthma (OR=1.72, CI95%=[0.95, 3.10]). For caesarean section and forcipal extraction there were no such relationships.

Conclusions
Prematurity is a risk factor for asthma reported at 6 years. A high ratio of head circumference to birth weight is a risk factor for any atopic disorder. Vacuum extraction was associated with a higher risk of allergy, and induced labour is a risk factor for inhalant allergy. All results should be viewed with the possibility of residual confounding.
Juvenile chinook salmon (Oncorhynchus tshawytscha) growth on the central California coast during the 1998 El Niño and 1999 La Niña
Authors: BRUCE MACFARLANE R. , RALSTON STEPHEN , ROYER CHANTELL , NORTON ELIZABETH C.
Published: September 2005

We assessed growth in subyearling chinook salmon (Oncorhynchus tshawytscha) during the 1998 El Niño and 1999 La Niña in the Gulf of the Farallones, a region of the continental shelf off central California seaward of the Golden Gate and the southernmost ocean entry point for the species in North America. Juvenile salmon demonstrated greater growth during this strong El Niño, when water temperature anomalies of more than +3°C were recorded at local buoys, than during the similarly strong 1999 La Niña. Slopes of regressions of weight on length, length on age, and weight on age were all significantly greater for juvenile salmon during the 1998 El Niño compared with those in the 1999 La Niña. Daily otolith increment widths, an estimator of somatic growth, corroborated population data. Between June 1 and August 9, mean increment widths for juvenile chinook salmon in 1998 were 3.54 ± 0.03 μm, significantly larger than the 3.13 ± 0.03 μm found in juveniles during the same time interval in 1999. Condition factor for juvenile chinook salmon entering the ocean at the Golden Gate was the same in both years, but became significantly greater in ocean fish during the 1998 El Niño than in ocean fish during the 1999 La Niña. Energy storage was significantly greater in ocean juvenile salmon during the 1998 El Niño as well. Mean triacylglycerol/cholesterol ratios increased following ocean entry in 1998, whereas they declined in ocean juveniles during 1999. Thus, not only was growth better in the El Niño period compared with La Niña, but lipid accumulation was also better. Oceanographic data for 1998 indicated elevated temperatures, lower salinity, greater freshwater outflow from San Francisco Bay, northerly flowing coastal currents, and positive upwelling index anomalies. This combination of environmental factors resulted in greater zooplankton productivity that, in conjunction with higher temperatures, allowed metabolic processes to enhance growth. Although El Niño events have certainly produced large‐scale, and often adverse, effects on ecosystems, the results of this study emphasize the importance of local oceanographic conditions to growth and other physiological and ecological processes.
Spatial correspondence between areas of concentration of Patagonian scallop (Zygochlamys patagonica) and frontal systems in the southwestern Atlantic
Authors: BOGAZZI EUGENIA , BALDONI ANA , RIVAS ANDRÉS , MARTOS PATRICIA , RETA RAÚL , ORENSANZ J. M. (LOBO) , LASTA MARIO , DELL'ARCIPRETE PATRICIA , WERNER FRANCISCO
Published: September 2005

It has been hypothesized that the geographical location of scallop beds in extensive shelf regions mirrors hydrographic structures (e.g. frontal systems) that favor the retention/concentration of pelagic larvae. Large, discontinuous concentrations of the Patagonian scallop (Zygochlamys patagonica) are known to have occurred recurrently (for more than 30 yr) at certain geographical locations over the extensive Patagonian shelf. These stocks, exploited since 1996, currently support one of the most important scallop fisheries in the world. Here, we investigate whether those aggregations are spatially coincidental with major frontal systems. Several pieces of information were used: historical survey data documenting the geographic distribution of the Patagonian scallop beds, catch and effort data from the commercial fleet, oceanographic data on frontal systems, and remote sensing imagery. We found that large‐scale aggregations do match the location of three major and very different frontal systems in the southwestern Atlantic: the Shelf‐Break Frontal System, the Northern Patagonia Frontal System, and the Southern Patagonia Frontal System. We describe the three frontal systems and their associated scallops fishing grounds and discuss which processes can contribute to sustaining the productivity of the scallop grounds in each case.
Evidence for atmosphere–ocean forcing of yellowtail flounder (Limanda ferruginea) recruitment in the Middle Atlantic Bight
Authors: SULLIVAN MARK C. , COWEN ROBERT K. , STEVES BRIAN P.
Published: September 2005

We investigated the relationship between large‐scale climate variability (the North Atlantic Oscillation, NAO), continental shelf hydrography, and year‐class strength of yellowtail flounder (Limanda ferruginea) in the Middle Atlantic Bight. Using long‐term environmental time series (1963–98), dominant winter NAO phase in the northeast region of the United States was correlated with local air temperature records from Block Island, Rhode Island (December–March). Air temperature also influenced the characteristics of a pool of remnant winter cold water on the continental shelf, such that negative NAO winters produced a colder‐than‐average summer cold pool, and vice versa. Smoothed data sets of L. ferruginea recruitment over the 36‐yr period (using Southern New England VPA and hindcast data) were highly correlated with the NAO and air temperature, highlighting the influence of multi‐year variability. Although less robust, the relationship with the NAO remained significant after removing equal‐but‐opposite long‐term linear trends from the series. Surprisingly, recruitment and cold pool bottom temperature were only marginally correlated. Data from independent 2‐m beam trawl and submersible sampling in the region (1994, 1996–2000) indicated a strong relationship between the abundance of recent settlers and cold pool temperature; however, this pattern was often modified by subsequent changes in cold pool stratification (fall overturn). These results underscore the dynamic role thermal habitats play in the lives of early stage benthic fishes. For yellowtail flounder, the generation of recruitment variability represents one endpoint of a complex interaction between large‐scale phenomena (climate) and more localized, event‐scale features (cold pool).
A 250 year comparison of historical, macrofossil and pollen records of aquatic plants in a shallow lake
Authors: DAVIDSON THOMAS A. , SAYER CARL D. , BENNION HELEN , DAVID CAROL , ROSE NEIL , WADE MAX P.
Published: September 2005

1. Sedimentary remains of aquatic plants, both vegetative (turions, leaves, spines) and reproductive (fruits, seeds, pollen), may provide a record of temporal changes in the submerged vegetation of lakes. An independent assessment of the degree to which these remains reflect past floristic change is, however, rarely possible.

2. By exploiting an extensive series of historical plant records for a small shallow lake we compare plant macrofossil (three cores) and pollen (one core) profiles with the documented sequence of submerged vegetation change since c. 1750 AD. The data set is based on 146 site visits with 658 observations including 42 taxa classified as aquatic, spanning 250 years.

3. Approximately 40% of the historically recorded aquatic taxa were represented by macro‐remains. In general macrofossils underestimated past species diversity, with pondweeds (three of eight historically recorded Potamogeton species were found) particularly poorly represented. Nonetheless, several taxa not reported from historical surveys (e.g. Myriophyllum alterniflorum and Characeae) were present in the sediment record.

4. The pollen record revealed taxa which left no macro‐remains (e.g. Littorella uniflora), and the macrofossil record provided improved taxonomic resolution for some taxa (e.g. Potamogeton) and a more reliable record of persistence, appearance and loss of others (e.g. Myriophyllum spp. and Nymphaeaceae).

5. Detrended correspondence analysis indicated that changes in the community composition evidenced by the palaeolimnological and historical records were synchronous and of a similar magnitude. Both records pointed to a major change at around 1800, with the historical record suggesting a more abrupt change than the sedimentary data. There was good agreement on a subsequent change c. 1930.

6. The palaeolimnological data did not provide a complete inventory of historically recorded species. Nevertheless, these results suggest that combined macrofossil and pollen records provide a reliable indication of temporal change in the dominant components of the submerged and floating‐leaved aquatic vegetation of shallow lakes. As such palaeolimnology may provide a useful tool for establishing community dynamics and successions of plants over decadal to centennial timescales.
Do phytoplankton communities correctly track trophic changes? An assessment using directly measured and palaeolimnological data
Authors: DOKULIL MARTIN T. , TEUBNER KATRIN
Published: September 2005

1. Measurements of total phosphorus (TP) concentrations since 1975 and a 50‐year time series of phytoplankton biovolume and species composition from Lake Mondsee (Austria) were combined with palaeolimnological information on diatom composition and reconstructed TP‐levels to describe the response of phytoplankton communities to changing nutrient conditions.

2. Four phases were identified in the long‐term record. Phase I was the pre‐eutrophication period characterised by TP‐levels of about 6 μg L−1 and diatom dominance. Phase II began in 1966 with an increase in TP concentration followed by the invasion of Planktothrix rubescens in 1968, characterising mesotrophic conditions. Phase III, from 1976 to 1979, had the highest annual mean TP concentrations (up to 36 μg L−1) and phytoplankton biovolumes (3.57 mm3 L−1), although reductions in external nutrient loading started in 1974. Phases II and III saw an expansion of species characteristic of higher nutrient levels as reflected in the diatom stratigraphy. Oligotrophication (phase IV) began in 1980 when annual average TP concentration, Secchi depth and algal biovolume began to decline, accompanied by increasing concentrations of soluble reactive silica.

3. The period from 1981 to 1986 was characterised by asynchronous trends. Annual mean and maximum total phytoplankton biovolume initially continued to increase after TP concentration began to decline. Reductions in phytoplankton biovolume were delayed by about 5 years. Several phytoplankton species differed in the timing of their responses to changing nutrient conditions. For example, while P. rubescens declined concomitantly with the decline in TP concentration, other species indicative of higher phosphorus concentrations, such as Tabellaria flocculosa var. asterionelloides, tended to increase further.

4. These data therefore do not support the hypotheses that a reduction in TP concentration is accompanied by (i) an immediate decline in total phytoplankton biovolume and (ii) persistence of the species composition characterising the phytoplankton community before nutrient reduction.
Response of a shallow Mediterranean lake to nutrient diversion: does it follow similar patterns as in northern shallow lakes?
Authors: ROMO SUSANA , VILLENA MARÍA‐JOSÉ , SAHUQUILLO MARÍA , SORIA JUAN M. , GIMÉNEZ MARIO , ALFONSO TERESA , VICENTE EDUARDO , MIRACLE MARIA R.
Published: September 2005

1. In view of the paucity of data on the response of warm shallow lakes to reductions in nutrient loading, this paper presents a long‐term limnological data set to document changes in the food‐web of a shallow Mediterranean lake (Lake Albufera, Valencia, Spain) that has experienced reductions in phosphorus (P) (77%) and nitrogen (N) (24%) loading following sewage diversion.

2. Nine years after sewage diversion, P concentration in the lake was reduced by 30% but remained high (TP = 0.34 mg L−1), although the mean water retention time in the lake was only 0.1 years. Nitrate concentrations did not significantly change, probably because the lake continued to receive untreated effluents from ricefields.

3. Chlorophyll a concentration was reduced by half (annual mean of 180 μg L−1). Cyanobacteria abundance remained high but its composition changed towards smaller species, both filamentous and chroococcal forms.

4. Cladocera abundance increased and reached peaks twice a year (December to March and July to September). After nutrient reduction, short‐term clear‐water phases (up to 5 weeks) occurred during February to March in several years, concomitant with annual flushing of the lake and lower fish densities. The abundance of Cladocera in winter contrasted with the spring peaks observed in northern restored shallow lakes. The zooplankton to phytoplankton biomass ratio remained lower than in northern temperate shallow lakes, probably because of fish predation on zooplankton.

5. Improvement of the water quality of Lake Albufera remained insufficient to counteract littoral reed regression or improve underwater light allowing submerged plants re‐colonise the lake.

6. Sewage diversion from Lake Albufera impacted the food web through the plankton, but higher trophic levels, such as fish and waterfowl, were affected to a lesser degree. Although the fish species present in the lake are mainly omnivorous, long‐term data on commercial fish captures indicated that fish communities changed in response to nutrient level and trophic structure as has been observed in restored shallow lakes at northern latitudes.

7. Phosphorus concentrations produced similar phytoplankton biomass in Lake Albufera as in more northern shallow lakes with abundant planktivorous fish and small zooplankton. However, in Lake Albufera, high average concentrations were maintained throughout the year. Overall, results suggest that nutrient control may be a greater priority in eutrophicated warm shallow lakes than in similar lakes at higher latitudes.
Ecological effects of reduced nutrient loading (oligotrophication) on lakes: an introduction
Authors: JOHN ANDERSON N. , JEPPESEN ERIK , SØNDERGAARD MARTIN
Published: September 2005

1. The variable ecological response of lakes to reduced nutrient loading (oligotrophication) at sites in Europe and North America was discussed at a workshop held in Silkeborg (Denmark) in January 2003. Studies of lake oligotrophication were presented based on both long‐term monitoring and data generated by palaeolimnological methods.

2. This introduction to the special issue provides short summaries of a series of the papers presented and their limnological context. Results show that the majority of lakes had approached a new equilibrium of phosphorus (P) and nitrogen (N) concentrations 10–15 years (P) and 0–5 years (N) after a major reduction in loading, irrespective of hydraulic retention time. Phytoplankton biomass decreased and a shift towards meso‐oligotrophic species dominance occurred. The fish responded surprisingly fast to the loading reduction in most lakes. As a result, the percentage of piscivores increased and total fish biomass declined markedly, which may explain an increase in the body size of cladocerans and an increase in the zooplankton to phytoplankton biomass ratio seen in many of the lakes.

3. Monitoring has in general been initiated after the effects of eutrophication became apparent. In this context palaeolimnological techniques become very useful because they allow limnologists to extend time scales of coverage and to define restoration targets and baseline conditions. Moreover, lake sediments pre‐dating anthropogenic disturbance can be used to examine ecological response to, for instance, climate variability, allowing problems associated with multiple stressors to be addressed.

4. It is concluded that there is a great need for a synthetic, holistic approach to studying lake oligotrophication, combining multiple techniques of palaeolimnological sediment analysis with detailed but temporally limited long‐term monitoring of chemical and biological variables. This is important, not least to assess future responses to nutrient loading reductions, as global warming will interact with a range of external stressors and ultimately affect lake management strategies to deal with the resultant feedbacks.
PHYTOCLOCK 1 encoding a novel GARP protein essential for the Arabidopsis circadian clock
Authors: Onai Kiyoshi , Ishiura Masahiro
Published: September 2005

Previously, we screened 50 000 seedlings of Arabidopsis thaliana carrying a PGI::LUC+ bioluminescence reporter gene mutagenized with ethylmethanesulfonate for mutants with phenotypes of extensively altered circadian rhythms, and identified three loci, PHYTOCLOCK 1 (PCL1), PCL2 and PCL3, whose mutations cause arrhythmia. Here we succeeded to clone the PCL1 gene and show that the PCL1 gene encodes a novel DNA binding protein belonging to the GARP protein family and is essential for a functional clock oscillator in A. thaliana. The PCL1 gene satisfies the requirements for the clock oscillator gene: (i) pcl1 null mutations caused arrhythmia in multiple circadian outputs, including expression of potential clock genes TOC1, CCA1 and LHY, and flowering lacked a photoperiodic response; (ii) PCL1 expression showed circadian rhythm in both constant light and constant dark; (iii) over‐expression of the PCL1 gene gradually caused arrhythmicity in all the multiple circadian outputs examined; and (iv) the PCL1 gene controlled its own expression via negative feedback. Therefore, the PCL1 gene is the clock oscillator gene essential to the generation of clock oscillation in the higher plant.
Business relationships in internet‐based electronic markets: the role of goodwill trust and transaction costs
Authors: Bunduchi Raluca
Published: September 2005

Abstract. Transaction costs and goodwill trust, which differentiate between transactional and collaborative relationships, were found in existing research to play a significant role in the way organizations use internet technologies to manage their relationships with customers and suppliers within electronic markets (EM). However, a thorough investigation of role that the two dimensions play together in shaping the use of EM is lacking from the mainstream literature. This research addresses transaction costs and goodwill trust together to clarify the transformations that internet use has brought on the nature of interorganizational relationships that develop between EM players. The research finds the use of EM in collaborative relationships is governed by trade‐offs between different outcomes that different EM functionalities have on organizational objectives. Organizations assess these trade‐offs, and select those functionalities that best serve to achieve their collaborative relational objectives. In contrast, no trade‐offs are find in the transactional model, as the use of EM here is driven principally by transaction cost reductions.
Perception and expectation gaps of information systems provider skills: the impact on user satisfaction
Authors: Tesch Debbie , Miller Ruth , Jiang James J , Klein Gary
Published: September 2005

Abstract.  Past research indicates that expectations play a crucial role in the final satisfaction of users of information systems (IS). This includes expectations regarding the skill levels exhibited by the providers of the IS services and products. Typically, the expectations are examined as gaps from perceived performance or as gaps from realistic expectations. The interaction of these gaps has not been thoroughly explored in past research, although recent theories anticipate both gaps are crucial in meeting the desires of the users. A matched pair sample of IS users and IS providers is used to collect data on expected skill levels and perceived delivery of the skills demanded. Gaps, both between these two stakeholder groups regarding expectations and within the user group regarding perceived delivery, are found to impact user satisfaction in a two‐way analysis. The results indicate that expectations should be managed to higher levels and commonly understood across the user and provider groups.
Searching for management information systems: coherence and change in the discipline
Authors: Larsen Tor J , Levine Linda
Published: September 2005

Abstract. The now familiar and longstanding discussion on the status of the field of management information systems (MIS) consists of at least two themes – the lack of coherence in MIS and the question of rigour vs. relevance (academic vs. practical concerns). The research questions we pose here ask: what themes or ideas represent the centre of MIS or its zones of coherence – or is diversity and fragmentation the rule? and will the centre or zones change over time? Within MIS research, is there evidence of theory building that contributes to a cumulative research tradition? Using a co‐word analysis approach – to analyse the patterns in discourse by measuring the association strengths of terms representative of relevant publications – the researchers found 62 specific centres of coherence. The data documented a high degree of change in centres of coherence over time. Evidence of theory building was extremely weak. A cumulative research tradition remains elusive. MIS centres of coherence change over time – we think, partly in response to practical pressures. We suggest that MIS opens a richer and more difficult debate on its theory, practice, and identity as a discipline in the 21st century university.