bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Nostoc punctiforme akinete‐expressed genes using differential display
Authors: Argueta Claudia , Yuksek Kamile , Patel Ronak , Summers Michael L.
Published: June 2006

Akinetes are spore‐like resting cells formed by certain filamentous cyanobacteria that have increased resistance to environmental stress. They can be found at low frequencies in dense cultures experiencing low light or phosphate limitation, but also form at high frequencies in a zwf mutant strain of Nostoc punctiforme following dark incubation in the presence of fructose. The wild‐type strain is capable of facultative heterotrophic growth under these conditions and does not form akinetes. To identify genes associated with akinete development, differential display was used to amplify and compare cDNA from a wild‐type and zwf mutant strain of N. punctiforme following a switch to dark heterotrophic conditions. Screening of candidate genes by reverse transcriptase real‐time quantitative PCR and subsequent testing for akinete‐specific expression using GFP transcriptional reporter plasmids lead to the identification of three novel akinete‐expressed genes. The genes identified from the screening encoded for proteins homologous to an aminopeptidase (aapN), a zinc protease (hap) and an ATP‐binding cassette (ABC)‐type transporter (aet). Expression of hap was also increased in developing hormogonia, a transient type of differentiated filament capable of gliding motility. Transcriptional start sites for akinete‐expressed genes were determined using random amplification of cDNA ends (RACE), and promoter regions were compared with orthologues in other filamentous cyanobacteria to identify putative regulatory sequences.
Quantifying rates of coastal progradation from sediment volume using GPR and OSL: the Holocene fill of Guichen Bay, south‐east South Australia
Authors: BRISTOW C. S. , PUCILLO K.
Published: June 2006

Guichen Bay on the south‐east coast of South Australia faces west towards the prevailing westerly winds of the Southern Ocean. The bay is backed by a 4 km wide Holocene beach‐ridge plain with more than 100 beach ridges. The morphology of the Guichen Bay strandplain complex shows changes in the width, length, height and orientation of beach ridges. A combination of geomorphological interpretation, shallow geophysics and existing geochronology is used to interpret the Holocene fill of Guichen Bay. Six sets of beach ridges are identified from the interpretation of orthorectified aerial photographs. The ridge sets are distinguished on the basis of beach‐ridge orientation and continuity. A 2·25 km ground‐penetrating radar (GPR) profile across the beach ridges reveals the sedimentary structures and stratigraphic units. The beach ridges visible in the surface topography are a succession of stabilized foredunes that overlie progradational foreshore and upper shoreface sediments. The beach progrades show multiple truncation surfaces interpreted as storm events. The GPR profile shows that there are many more erosion surfaces in the subsurface than beach ridges on the surface. The width and dip of preserved beach progrades imaged by GPR shows that the shoreface has steepened from around 2·9° to around 7·5°. The changes in beach slope are attributed to increasing wave energy associated with beach progradation into deeper water as Guichen Bay was infilled. At the same time, the thickness of the preserved beach progrades increases slightly as the beach prograded into deeper water. Using the surface area of the ridge sets measured from the orthophotography, and the average thickness of upper shoreface, foreshore and coastal dune sands interpreted from the GPR profile, the volume of Holocene sediments within three of the six sets of beach‐ridge accretion has been calculated. Combining optically stimulated luminescence (OSL) ages and volume calculations, rates of sediment accumulation for Ridge Sets 3, 4 and 5 have been estimated. Linear rates of beach‐ridge progradation appear to decrease in the mid‐Holocene. However, the rates of sediment accumulation calculated from beach volumes have remained remarkably consistent through the mid‐ to late Holocene. This suggests that sediment supply to the beach has been constant and that the decrease in the rate of progradation is due to increasing accommodation space as the beach progrades into deeper water. Changes in beach‐ridge morphology and orientation reflect environmental factors such as changes in wave climate and wind regime.
Anomalous geochemical provenance and weathering history of Plio‐Pleistocene glaciomarine fjord strata, Bardin Bluffs Formation, East Antarctica
Authors: PASSCHIER SANDRA , WHITEHEAD JASON M.
Published: June 2006

Major and trace element chemical analyses of the Plio‐Pleistocene Bardin Bluffs Formation, on the margin of a major ice‐stream of the East Antarctic Ice Sheet, yield an anomalous chemically altered sediment composition. The Bardin Bluffs Formation of the Pagodroma Group is one of the key deposits on the Antarctic continent recording glaciomarine sedimentation under open marine fjord conditions as recently as the Plio‐Pleistocene. In modern fjords occupied by outlet glaciers of ice sheets, the composition of fine‐grained terrigenous sediments approaches that of unweathered rock types exposed upstream. In the Bardin Bluffs Formation, average abundances of stable elements (Ti, Al, Zr) approach average upper crustal compositions and the element ratios are consistent with sediments with a cratonic source, implying glacial dispersal from a large shield area through the Lambert Glacier drainage system. Interestingly, the chemical index of alteration (CIA) of these sediments has values similar to those of average shales formed under conditions of chemical weathering. The sediments are particularly depleted in silicate Ca, which has been observed elsewhere in glacial muds sourced from pre‐glacial saprolites. The anomalous chemistry of the Bardin Bluffs Formation can be explained by a sequence of events, involving chemical weathering prior to glacial expansion and erosion. The presence of a remnant 1·5 m deep late Neogene weathering profile at the base of the Bardin Bluffs sequence corroborates this conclusion. Supply of large quantities of chemically weathered materials to Antarctic marginal basins requires at least partial deglaciation of the continent and was previously regarded as uncharacteristic for late Neogene Antarctica.
Characterization of a new xyloglucan endotransglucosylase/hydrolase (XTH) from ripening tomato fruit and implications for the diverse modes of enzymic action
Authors: Saladié Montserrat , Rose Jocelyn K. C. , Cosgrove Daniel J. , Catalá Carmen
Published: June 2006

Xyloglucan endotransglucosylase/hydrolases (XTHs) are cell wall‐modifying enzymes that align within three or four distinct phylogenetic subgroups. One explanation for this grouping is association with different enzymic modes of action, as XTHs can have xyloglucan endotransglucosylase (XET) or endohydrolase (XEH) activities. While Group 1 and 2 XTHs predominantly exhibit XET activity, to date the activity of only one member of Group 3 has been reported: nasturtium TmXH1, which has a highly specialized function and hydrolyses seed‐storage xyloglucan rather than modifying cell wall structure. Tomato fruit ripening was selected as a model to test the hypothesis that preferential XEH activity might be a defining characteristic of Group 3 XTHs, which would be expressed during processes where net xyloglucan depolymerization occurs. Database searches identified 25 tomato XTHs, and one gene (SlXTH5) was of particular interest as it aligned within Group 3 and was expressed abundantly during ripening. Recombinant SlXTH5 protein acted primarily as a transglucosylase in vitro and depolymerized xyloglucan more rapidly in the presence than in the absence of xyloglucan oligosaccharides (XGOs), indicative of XET activity. Thus, there is no correlation between the XTH phylogenetic grouping and the preferential enzymic activities (XET or XEH) of the proteins in those groups. Similar analyses of SlXTH2, a Group 2 tomato XTH, and nasturtium seed TmXTH1 revealed a spectrum of modes of action, suggesting that all XTHs have the capacity to function in both modes. The biomechanical properties of plant walls were unaffected by incubation with SlXTH5, with or without XGOs, suggesting that XTHs do not represent primary cell wall‐loosening agents. The possible roles of SlXTH5 in vivo are discussed.
Genetical metabolomics of flavonoid biosynthesis in Populus: a case study
Authors: Morreel Kris , Goeminne Geert , Storme Véronique , Sterck Lieven , Ralph John , Coppieters Wouter , Breyne Peter , Steenackers Marijke , Georges Michel , Messens Eric , Boerjan Wout
Published: June 2006

Genetical metabolomics [metabolite profiling combined with quantitative trait locus (QTL) analysis] has been proposed as a new tool to identify loci that control metabolite abundances. This concept was evaluated in a case study with the model tree Populus. Using HPLC, the peak abundances were analyzed of 15 closely related flavonoids present in apical tissues of two full‐sib poplar families, Populus deltoides cv. S9‐2 × P. nigra cv. Ghoy and P. deltoides cv. S9‐2 × P. trichocarpa cv. V24, and correlation and QTL analysis were used to detect flux control points in flavonoid biosynthesis. Four robust metabolite quantitative trait loci (mQTL), associated with rate‐limiting steps in flavonoid biosynthesis, were mapped. Each mQTL was involved in the flux control to one or two flavonoids. Based on the identities of the affected metabolites and the flavonoid pathway structure, a tentative function was assigned to three of these mQTL, and the corresponding candidate genes were mapped. The data indicate that the combination of metabolite profiling with QTL analysis is a valuable tool to identify control points in a complex metabolic pathway of closely related compounds.
Partially edited RNAs are intermediates of RNA editing in plant mitochondria
Authors: Verbitskiy Daniil , Takenaka Mizuki , Neuwirt Julia , Van Der Merwe Johannes A. , Brennicke Axel
Published: June 2006

RNA editing in flowering plant mitochondria addresses several hundred specific C nucleotides in individual sequence contexts in mRNAs and tRNAs. Many of the in vivo steady state RNAs are edited at some sites but not at others. It is still unclear whether such incompletely edited RNAs can either be completed or are aborted. To learn more about the dynamics of the substrate recognition process, we investigated in vitro RNA editing at a locus in the atp4 mRNA where three editing sites are clustered within four nucleotides. A single cis‐element of about 20 nucleotides serves in the recognition of at least two sites. Competition with this sequence element suppresses in vitro editing. Surprisingly, unedited and edited competitors are equally effective. Experiments with partially pre‐edited substrates indicate that indeed the editing status of a substrate RNA does not affect the binding affinity of the specificity factor(s). RNA molecules in which all editing sites are substituted by either A or G still compete, confirming that editing site recognition can occur independently of the actual editing site. These results show that incompletely edited mRNAs can be substrates for further rounds of RNA editing, resolving a long debated question.
Specific oral tolerance induction in food allergy
Authors: Niggemann B. , Staden U. , Rolinck‐Werninghaus C. , Beyer K.
Published: June 2006

Specific oral tolerance in food allergy can be induced by oral administration of the offending food, starting with very low dosages, gradually increasing the daily dosage up to an amount equivalent to a usually relevant dose for daily intake, followed up by a daily maintenance dose. Unfortunately, the body of scientific evidence concerning specific oral tolerance induction (SOTI) is still rather poor. Following a couple of case reports, only a few studies on a limited number of patients including different allergens are available. So far, no placebo‐controlled, long‐term study has been published. Concerning the underlying immunological mechanism, a limited number of studies have reported on changes in antibody production, and more recently on the role of different T‐cell populations. The individual pattern of clinical reaction during SOTI seems to vary considerably between patients and from allergen to allergen. Arguments in favour of SOTI are the safety for an inadvertent intake of the offending food and the increased quality of life. Arguments against SOTI are the necessity for a regular intake and possible long‐term compliance problems. Indications to consider SOTI in the future might be (i) importance of the incriminated food for the individual nutritional regimen, (ii) avoidance of the corresponding food cannot be assured and (iii) persistent severe food allergy. However, before SOTI can be recommended for the daily praxis, more studies are warranted to clarify whether certain patients may profit from SOTI and to understand the underlying mechanism.
Modulation of allergic immune responses by mucosal application of recombinant lactic acid bacteria producing the major birch pollen allergen Bet v 1
Authors: Daniel C. , Repa A. , Wild C. , Pollak A. , Pot B. , Breiteneder H. , Wiedermann U. , Mercenier A.
Published: June 2006

Background:  Probiotic lactic acid bacteria (LAB) are able to modulate the host immune system and clinical trials have demonstrated that specific strains have the capacity to reduce allergic symptoms. Therefore, we aimed to evaluate the potential of recombinant LAB producing the major birch pollen allergen Bet v 1 for mucosal vaccination against birch pollen allergy.

Methods:  Recombinant Bet v 1‐producing Lactobacillus plantarum and Lactococcus lactis strains were constructed. Their immunogenicity was compared with purified Bet v 1 by subcutaneous immunization of mice. Intranasal application of the live recombinant strains was performed to test their immunomodulatory potency in a mouse model of birch pollen allergy.

Results:  Bet v 1 produced by the LAB was recognized by monoclonal anti‐Bet v 1 and IgE antibodies from birch pollen‐allergic patients. Systemic immunization with the recombinant strains induced significantly lower IgG1/IgG2a ratios compared with purified Bet v 1. Intranasal pretreatment led to reduced allergen‐specific IgE vs enhanced IgG2a levels and reduced interleukin (IL)‐5 production of splenocytes in vitro, indicating a shift towards non‐allergic T‐helper‐1 (Th1) responses. Airway inflammation, i.e. eosinophils and IL‐5 in lung lavages, was reduced using either Bet v 1‐producing or control strains. Allergen‐specific secretory IgA responses were enhanced in lungs and intestines after pretreatment with only the Bet v 1‐producing strains.

Conclusions:  Mucosal vaccination with live recombinant LAB, leading to a shift towards non‐allergic immune responses along with enhanced allergen‐specific mucosal IgA levels offers a promising approach to prevent systemic and local allergic immune responses.
EuropeanPolistesvenom allergy
Authors: Severino M. G. , Campi P. , Macchia D. , Manfredi M. , Turillazzi S. , Spadolini I. , Bilò M. B. , Bonifazi F.
Published: June 2006

The AmericanPolistesspecies venom mixture – that ofP. annularis,P. fuscatus,P. metricusandP. exclamans– was the only commercially available mixture for diagnosis and therapy until 1996. However, these species ofPolistesare not present in Europe, whereP. dominulusandP. gallicusand to a lesser extentP. nimphusare widespread. The aim of this study was to assess the allergenic differences among the commercial American mix,P. dominulusandP. gallicusvenom in European patients and therefore to verify if this mixture is suitable for diagnosis in these patients. We carried out skin tests, radioallergosorbent tests (RAST) and RAST inhibition in Italian patients with adverse reactions toPolistesstings. RAST inhibition results demonstrated that cross‐reactivity between the American and European species is only partial and thatP. dominulusandP. gallicusvenoms have exclusive allergens. Skin tests and direct RAST confirmed these results and also showed that EuropeanPolistesvenom is more suitable than the American mix in Italian patients. Moreover, we found a high rate of cross‐reactivity betweenP. dominulusandP. gallicus. To conclude,P. dominulusand/orP. gallicusvenoms are necessary for diagnosis and therefore in the therapy of European patients.
Are risk factors of childhood asthma predicting disease persistence in early adulthood different in the developing world?
Authors: Sekerel B. E. , Civelek E. , Karabulut E. , Yildirim S. , Tuncer A. , Adalioglu G.
Published: June 2006

Background:  Predictive factors of childhood asthma for favorable prognosis may differ between populations where a variety of genetic and environmental factors are present.

Objectives:  To document the factors predicting disease persistence in early adulthood in Turkey.

Methods:  An outpatient cohort (n = 115) with a mean follow‐up duration of 11.4 ± 0.2 years was evaluated. Complete remission was defined as no asthma symptoms, no use of controller medication, no airflow limitation and no airway hyper‐responsiveness, and clinical remission as no symptoms and no use of controller medication, within the past year.

Results:  The mean ages during referral and at the final visit were 5.8 ± 0.2 and 17.1 ± 0.2 years, respectively. Thirty‐one (27%) were in complete remission, and a further 30 (26%) in clinical remission. In multivariate logistic models, diminished airflow [forced expiratory volume in 1 s (FEV1) <80%vs≥80%] at the initial lung function test predicted current diminished airflow (8.422; 2.202–32.206) (odds ratio; 95% confidence interval), and presence of obstructive pattern (FEV1/forced vital capacity (FVC) <80%vs≥80%) predicted current obstructive pattern (29.333; 3.022–284.724). Furthermore, female gender appeared to predict persistence of asthma symptoms (3.330; 1.250–8.333) and absence of clinical remission (2.398; 1.038–5.254); eosinophilia predicted persistence of symptoms (4.271; 1.080–16.889) and presence of airway hyper‐responsiveness (3.723; 1.129–12.278).

Conclusions:  Diminished airflow, female gender and eosinophilia appear to predict an adverse outcome of childhood asthma, supporting the concept that variability may exist between populations.
IL‐25 regulates the expression of adhesion molecules on eosinophils: mechanism of eosinophilia in allergic inflammation
Authors: Cheung P. F. Y. , Wong C. K. , Ip W. K. , Lam C. W. K.
Published: June 2006

Background:  Interleukin‐25 (IL‐25) is a novel T‐helper‐2 (Th2) cytokine of the IL‐17 family that plays a key role in allergic inflammation. Recent studies reported that over‐expression of IL‐25 in mouse induces eosinophilia. We investigated the effect of IL‐25 on the expression of several adhesion molecules on human eosinophils and the underlying intracellular mechanisms.

Methods:  Viability of eosinophils was measured by annexin V‐flourescein isothiocyanate (FITC) assay. Gene expression and surface expression of intercellular adhesion molecule (ICAM)‐1 (CD54), ICAM‐3 (CD50), L‐selectin (CD62L), leukocyte function‐associated antigen (LFA‐1) (CD11a/CD18) and very late antigen‐4 (VLA‐4, CD49d/CD29) on eosinophils were measured by reverse transcriptase‐polymerase chain reaction (RT‐PCR) and flow cytometry, respectively. Adhesion of eosinophils to fibronectin was assessed using the fibronectin‐coated insert system.

Results:  Viability of eosinophils was significantly enhanced by IL‐25 from 41% to 76% dose‐dependently. IL‐25 could significantly upregulate the surface expression of ICAM‐1, but suppress those of ICAM‐3 and L‐selectin on eosinophils in a dose‐dependent manner. Adhesion of eosinophils to fibronectin was also significantly enhanced by IL‐25. Besides, pre‐incubation with p38 mitogen‐activated protein kinases (MAPK) inhibitor SB203580, C‐Jun NH2‐terminal protein kinases (JNK) inhibitor SP600125 and proteosome inhibitor MG‐132 could significantly restrain the effects of IL‐25 on surface expression of L‐selectin, ICAM‐1 and ICAM‐3, respectively, and also on the adhesion of eosinophils onto fibronectin (all P < 0.05).

Conclusions:  Our findings suggest an essential role of IL‐25 in enhancing survival and regulating surface expression of ICAM‐1, ICAM‐3 and L‐selectin on human eosinophils through the activation of p38 MAPK, JNK and nuclear factor (NF)‐κB pathways, thereby shedding light on the molecular mechanisms of IL‐25‐induced eosinophilia in allergic inflammation.
Inhibition of type I allergic responses with nanogram doses of replicon‐based DNA vaccines
Authors: Scheiblhofer S. , Gabler M. , Leitner W. W. , Bauer R. , Zoegg T. , Ferreira F. , Thalhamer J. , Weiss R.
Published: June 2006

Background:  Allergic diseases have become a major public health problem in developed countries; yet, no reliable, safe and consistently effective treatment is available. DNA immunization has been shown to prevent and balance established allergic responses, however, the high dose of conventional DNA vaccines necessary for the induction of anti‐allergic reactions and their poor immunogenicity in primates require the development of new allergy DNA vaccines. We evaluated protective and therapeutic effects of a Semliki‐Forest Virus replicase‐based vs a conventional DNA vaccine in BALB/c mice using the model allergen β‐galactosidase.

Methods:  Immunoglobulin (Ig)E suppression was determined by a basophil release assay as an in vitro correlate for allergen‐specific crosslinking capacity of IgE reflecting the in vivo situation in an allergic individual. Th1 memory responses were measured by cytokine detection via enzyme‐linked immunosorbent assay (ELISA) and enzyme‐linked immunospot assay (ELISPOT).

Results:  Nanogram amounts of a replicase‐based vector triggered a Th1 response comparable with that achieved with the injection of 20 000‐times more copies of a conventional DNA plasmid, and induced IgE suppression in both a protective and a therapeutic setting.

Conclusions:  Replicase‐based DNA vaccines fulfill the stringent criteria for an allergy DNA vaccine, i.e. low dose, strong Th1 immunogenicity and memory, lack of ‘therapy‐induced’ IgE production and anaphylactic side effects. Moreover, by triggering apoptosis in transfected cells, their unique ‘immunize and disappear’ feature minimizes the hypothetical risks of genomic integration or induction of autoimmunity.
Engineered recombinant ovomucoid third domain can desensitize Balb/c mice of egg allergy
Authors: Rupa P. , Mine Y.
Published: June 2006

The purpose of this study was to determine the in vivo desensitization efficacy of a hypoallergenic variant of egg white ovomucoid third domain (DIII) in Balb/c mice model. We mapped the immunodominant B‐cell epitopes of ovomucoid in Balb/c mice. A hypoallergenic ovomucoid third domain (GMFA) mutant isoform having ablated allergenicity against egg allergic patient's sera was used to desensitize DIII‐sensitized Balb/c mice by intraperitoneal injections. Ovomucoid DIII generated high levels of plasma histamine and specific immunoglobulin (Ig)E levels, and increased Th2 type cytokine (IL‐4). On the other hand, the allergic response of mice desensitized with the GMFA was found to be significantly inhibited and abrogated by prevention of anaphylaxis reactions, low histamine levels and increased Th1‐type cytokine (INF‐γ). It was found that significantly higher levels of IL‐10 and IL‐12 were secreted in the desensitized group Desensitization with the GMFA antigen also suppressed synthesis of DIII specific‐IgE levels and enhanced specific IgG2a and IgG levels compared with the group treated with the DIII antigen. The present results indicated that hyposensitization with the GMFA can desensitize or down‐regulate the allergic response in Balb/c mice and this hypoallergenic variant of ovomucoid DIII can shift an ongoing allergen‐specific Th2 response towards a Th1 skewed response.
Mechanisms of allergen specific immunotherapy – T‐cell tolerance and more
Authors: Jutel M. , Akdis M. , Blaser K. , Akdis C. A.
Published: June 2006

Specific immune suppression and induction of tolerance are essential processes in the regulation and circumvention of immune defence. The balance between allergen‐specific T‐regulatory (Treg) cells and T helper 2 cells appears to be decisive in the development of allergic and healthy immune response against allergens. Treg cells consistently represent the dominant subset specific for common environmental allergens in healthy individuals. In contrast, there is a high frequency of allergen‐specific T helper 2 cells in allergic individuals. A decrease in interleukin (IL)‐4, IL‐5 and IL‐13 production by allergen‐specific CD4+ T cells due to the induction of peripheral T cell tolerance is the most essential step in allergen‐specific immunotherapy (SIT). Suppressed proliferative and cytokine responses against the major allergens are induced by multiple suppressor factors, such as cytokines like IL‐10 and transforming growth factor (TGF)‐β and cell surface molecules like cytotoxic T lymphocyte antigen‐4, programmed death‐1 and histamine receptor 2. There is considerable rationale for targeting T cells to increase efficacy of SIT. Such novel approaches include the use of modified allergens produced using recombinant DNA technology and adjuvants or additional drugs, which may increase the generation of allergen‐specific peripheral tolerance. By the application of the recent knowledge in Treg cells and related mechanisms of peripheral tolerance, more rational and safer approaches are awaiting for the future of prevention and cure of allergic diseases.
Autologous hematopoietic stem cell transplantation for progressive multiple sclerosis: report of efficacy and safety at three yr of follow up in 21 patients
Authors: Ni Xiu‐Shi , Ouyang Jiang , Zhu Wen‐Hui , Wang Chong , Chen Bing
Published: June 2006

Abstract:  Objective:  To observe the efficacy and toxicity of autologous hematopoietic stem cell transplantation (HSCT) in progressive multiple sclerosis (PMS).

Methodology:  Twenty‐one patients with PMS were treated with autologous HSCT. Stem cells were mobilized with cyclophosphamide (CY) and granulocyte colony‐stimulating factor. After conditioning regimen of CY and total body irradiation or BEAM, stem cells were reinfused. CD34+ cell selection of the graft was performed and anti‐thymocyte globulin was given for T‐cell depletion. The probabilities of confirmed progression‐free survival and disease activity‐free survival were used to assess the efficacy and the adverse experiences were recorded to detect the toxicities.

Results:  The median follow‐up time was 42 (6–65) months. The probabilities of confirmed progression‐free survival and the disease activity‐free survival were 75% and 33.3%, respectively. The principal adverse events included allergy, infection, elevation of liver enzymes, transient neurologic deterioration and depression. Two patients died of severe pneumonia and varicella‐zoster virus hepatitis, at 4.5 and 15 months post‐transplant, respectively.

Conclusions:  Autologous HSCT seems beneficial to PMS. However, more patients and longer follow up would be required to assess the risk/benefit ratio.
Is Mate Provisioning Predicted by Ornamentation? A Test with Northern Cardinals (Cardinalis cardinalis)
Authors: Jawor Jodie M. , Breitwisch Randall
Published: June 2006

Male birds of many species feed their mates during courtship and incubation. The amount of food provided can be substantial and even essential for successful reproduction in some species, and can influence female nest attentiveness in many others. Additionally, mate provisioning may predict later nestling feeding rates. Females may thus benefit from being able to determine male provisioning effort. We assessed the expression of several ornaments, known to indicate condition in male northern cardinals (Cardinalis cardinalis), and compared these with mate provisioning rates, nestling feeding rates, and nest attentiveness. We found that male ornamentation may not be indicative of mate provisioning rates. Mate provisioning rate did not co‐vary with reproductive success, male feedings to nestlings, or nest attentiveness of females. However, females which were fed more often during incubation tended to provision nestlings less. Reduced female parental effort following extensive incubation feeding may be indicative of females using incubation feeding to assess future male parental effort. Male hormonal condition that favors high rates of nestling provisioning may be a proximate cause of mate provisioning during incubation, even in the absence of selection, favoring high rates of mate provisioning. Both sexes may have capitalized on this unselected behavior.
Genetic diversity contribution to errors in short oligonucleotide microarray analysis
Authors: Kirst Matias , Caldo Rico , Casati Paula , Tanimoto Gene , Walbot Virginia , Wise Roger P. , Buckler Edward S.
Published: June 2006

DNA arrays based on short oligonucleotide (≤ 25‐mer) probes are being developed for many species, and are being applied to quantify transcript abundance variation in species with high genetic diversity. To define the parameters necessary to design short oligo arrays for maize (Zea mays L.), a species with particularly high nucleotide (single nucleotide polymorphism, SNP) and insertion‐deletion (indel) polymorphism frequencies, we analysed gene expression estimates generated for four maize inbred lines using a custom Affymetrix DNA array, and identified biases associated with high levels of polymorphism between lines. Statistically significant interactions between probes and maize inbreds were detected, affecting five or more probes (out of 30 probes per transcript) in the majority of cases. SNPs and indels were identified by re‐sequencing; they are the primary source of probe‐by‐line interactions, affecting probeset level estimates and reducing the power of detecting transcript level variation between maize inbreds. This analysis identified 36 196 probes in 5118 probesets containing markers that may be used for genotyping in natural and segregating populations for association gene analysis and genetic mapping.
Evolution of the Scattering Coefficients of the Camassa–Holm Equation, for General Initial Data
Authors: Kaup D. J.
Published: June 2006

We consider the Camassa–Holm equation for general initial data, particularly when the potential in the scattering problem of the Lax pair, m+κ, becomes negative over a finite region. We show that the direct scattering problem of the eigenvalue problem of the Lax pair for this equation may be solved by dividing the spatial infinite interval into a union of separate intervals. Inside each of these intervals, the initial potential is uniformly either positive or negative. Due to this, one can define Jost functions inside each interval, each of which will have a uniform asymptotic form. We then demonstrate that one can obtain the t‐evolution of the scattering coefficients of the scattering matrix of each interval. In the process, we also demonstrate that the evolution of the zeros of m+κ can be given entirely in terms of limits of the scattering coefficients at singular points.
Rhetoric in Economic Research: The Case of Gender Wage Differentials
Authors: WEICHSELBAUMER DORIS , WINTER‐EBMER RUDOLF
Published: June 2006

Scientific rhetoric can have a profound impact on the perception of research; it can also drive and direct further research efforts. What determines whether results are discussed in a neutral or a judgmental way? How precise and convincing do results have to be so that authors call for significant policy changes? These questions are in general difficult to answer, because rhetoric on the one hand, and content and methodology of the paper on the other, cannot be separated easily. We therefore used a unique example to examine this question empirically: the analysis of gender wage differentials. Here, the Blinder–Oaxaca decomposition represents a standard research method that compares male and female earnings, holding observable factors constant. We analyzed close to 200 papers to investigate what drives authors to talk about discrimination, whether and when they call for policy activism, or when they are more hesitant to do so.

 Our results show that American authors are more reluctant to refer to discrimination. So are women, but only with respect to the titles of their papers. Furthermore, we find that the better the data and method used in a paper, the more likely an author is to assign his/her estimate of unequal wages to discrimination. The contrary is true the higher the prestige of the author or the research outlet.
Temporal resource partitioning by bats at water holes
Authors: Adams R. A. , Thibault K. M.
Published: June 2006

The temporal axis of niche (temporally based resource partitioning) is an understudied mechanism for resource partitioning in mammals even though it provides a potential means for species coexistence. Herein we evaluate species‐specific use curves based upon capture times during the overlapping activity of bat species at two water holes in an arid environment where bats likely suffer high levels of evaporative water loss during roosting. During the first 75 min after sunset, intense bat activity at each water hole ensued and, although visitation times overlapped, there was a significant difference among species use curves. In addition, pairwise comparisons showed high similarity in temporal visitation patterns across sites for species in which capture numbers were comparable, whereas other species shifted to significantly earlier arrival times when their capture numbers were higher. There were no significant differences in mean roost site emergence times among species, nor in distance of roost sites from water holes. Our data provide one of the few statistically verified examples of fine‐grain temporal partitioning by mammals simultaneously using the same resource. We conclude that temporal partitioning helps facilitate bat species coexistence in water‐stressed environments.
The use of heart rate variability measures to assess autonomic control during exercise
Authors: Sandercock G. R. H. , Brodie D. A.
Published: June 2006

Heart rate variability (HRV) is a non‐invasive indicator of cardiac autonomic modulation at rest. During rhythmic exercise, global HRV decreases as a function of exercise intensity. Measures reflecting sympathovagal interactions at rest do not behave as expected during exercise. This makes interpretation of HRV measures difficult, especially at higher exercise intensities. This problem is further confounded by the occurrence of non‐neural oscillations in the high‐frequency band due to increased respiratory effort.

Alternative data treatments, such as coarse graining spectral analysis (CGSA), have demonstrated expected changes in autonomic function during exercise with some success. The separation of harmonic from fractal and/or chaotic components of HRV and study of the latter during exercise have provided further insight into cardioregulatory control. However, more research is needed. Some cross‐sectional differences between HRV in athletes and controls during exercise are evident and data suggest longitudinal changes may be possible.

Standard spectral HRV analysis should not be applied to exercise conditions. The use of CGSA and non‐linear analyses show much promise in this area. Until further validation of these measures is carried out and clarification of the physiological meaning of such measures occurs, HRV data regarding altered autonomic control during exercise should be treated with caution.
Scapulothoracic latent muscle reaction timing comparison between trained overhead throwers and untrained control subjects
Authors: Brindle T. J. , Nyland J. A. , Nitz A. J. , Shapiro R.
Published: June 2006

Aim: This study evaluated select scapulothoracic muscles for training‐induced latent muscle reaction timing (LMRT) changes. Comparisons were also made between the dominant and non‐dominant upper extremities and between individual muscles.

Materials and methods: Fifteen male trained overhead throwers (college baseball pitchers) and 15 male untrained, age‐matched control subjects participated in this study. Scapulothoracic muscle activation data were collected as subjects attempted to stop a variably timed, sudden glenohumeral joint internal rotation perturbation.

Results: Training group differences were not evident for LMRT (P=0.56), however upper extremity dominance (P=0.003) and test muscle (P=0.0002) displayed significant differences. Dominant upper extremity upper trapezius muscle LMRT (72.5±26 ms) occurred later than non‐dominant upper trapezius muscle LMRT (60.0±14.1 ms, P=0.001). Dominant upper extremity middle trapezius‐rhomboid muscle LMRT (60.0±16.2 ms) occurred later than non‐dominant middle trapezius‐rhomboid muscle LMRT (50.2±12.6 ms, P=0.004). Dominant upper extremity upper trapezius muscle LMRT also occurred later than serratus anterior (55.7±16.0 ms, P=0.001) and middle trapezius‐rhomboid LMRT (60.2±16 ms, P=0.003). Mean overall dominant upper extremity LMRT (62.7±19.4 ms) was delayed compared with mean overall non‐dominant upper extremity LMRT (53.9±12.4 ms, P=0.003).

Clinical consequences: Although training was not found to influence scapulothoracic LMRT, differences were observed between the dominant and non‐dominant upper extremities. Consistent LMRT delays at the dominant upper extremity suggest possible neuromuscular timing differences to enable prolonged glenohumeral joint and scapulothoracic articulation acceleration before deceleration through eccentric muscle activation. Both trained and untrained overhead throwers displayed this response. Variable perturbation test velocities, and in‐season testing of larger subject groups may be needed to better elucidate the more subtle differences associated with training.
Implant Treatment in the Edentulous Maxillae: A 15‐Year Follow‐Up Study on 76 Consecutive Patients Provided with Fixed Prostheses
Authors: Jemt Torsten , Johansson Jesper
Published: June 2006

Background:  Few long‐term follow‐up studies are available on implant treatment based on patient level data related to time.

Purpose  The aim of this study was to report 15‐year patient‐based data in relation to time of follow up after treatment with fixed prostheses supported by implants in the edentulous upper jaw.

Materials and Methods  Seventy‐six edentulous consecutive patients, provided with 450 turned Brånemark implants, were followed up with regard to maintenance, complications, and radiographs taken during the follow‐up period.

Results  Forty‐four patients provided with 247 implants were lost to follow up. Patients followed up for 15 years showed as a group a trend of better implant survival than patients lost to follow up (p > .05). Altogether, 37 implants and 5 fixed prostheses failed during the follow‐up period. Most implants were lost at abutment surgery (n− 15) and another nine during the first year of function. The 15‐year implant and fixed prosthesis cumulative survival rate was 90.9 and 90.6%, respectively. Resin veneer fractures caused most problems, more frequent in the earlier stage while severe wear increased in the later stage of follow up. No implant fractures or loosening of abutment/bridge locking screws were noted. The mean marginal bone loss was 0.5 mm (SD 0.47) after 5 years, followed by only minimal average changes during the following years. No radiographic parameter showed any time‐dependent relationship. The percentage of patients presenting at least one implant with more than 2.0‐mm bone loss was 4.9% in the interval from 0 to 5 years and 4.0% between 10 and 15 years. Only 1.3% of implants showed >3.0 mm accumulated bone loss after 15 years.

Conclusion  Implant treatment in the edentulous upper jaw functions well in a 15‐year time perspective, but an insignificant trend of higher implant failures was observed for patients lost to follow up. Besides wear and fractures of veneers, no other parameter showed any time‐related relationship, indicating an increased risk for more complications during later stages of follow up. However, accumulation of smaller amount of bone loss during the years resulted in an increasing number of implants and patients with bone levels below the third thread, which could be speculated to increase future maintenance after 15 years.
Moderately Roughened‐ and Roughened‐Surface Implants Used as Rigid Orthodontic Anchorage: A Case Series
Authors: Kato Satoshi , Kato Michiko
Published: June 2006

Background  Osseointegrated implants, especially Brånemark turned‐surface implants, have been shown to function as stable and efficient orthodontic anchors. While it is generally accepted that prostheses can be attached to implants that have been used as anchors, it has not been clarified if the same applies to moderately roughened‐ and roughened‐surface implants.

Purpose  The purpose of the present study was to assess the differences between moderately roughened‐ and roughened‐surface implants that are used as orthodontic anchors and then bonded with prostheses and those that are bonded with prostheses without serving as orthodontic anchors.

Materials and Methods  A total of 43 moderately roughened‐ and roughened‐surface implants (ITI titanium plasma spray TPS®] Straumann AG, Waldenburg, Switzerland], ITI sandblasted large‐grit acid‐etched SLA®] Straumann AG], Nobel TiUniteTM Nobel Biocare AB, Göteborg, Sweden]) were placed in 11 partially edentulous patients, aged 35–61 years (two men and nine women). After an appropriate healing period, orthodontic therapy was performed in 11 patients using 27 implants as orthodontic anchors. After completion of the orthodontic therapy, the prostheses were attached at the same time to both types of implants: the 27 implants that were used as anchors, and 16 implants that were not used as anchors. All 11 patients were followed up regularly.

Results:  Regardless of use as orthodontic anchorage, all implants maintained osseointegration and continued to function properly.

Conclusion:  No differences existed in therapeutic results after prosthesis bonding whether or not moderately roughened‐ and roughened‐surface implants were used as orthodontic anchors.
Melatonin
Authors: Pandi‐Perumal S. R. , Srinivasan V. , Maestroni G. J. M. , Cardinali D. P. , Poeggeler B. , Hardeland R.
Published: June 2006

Melatonin is a ubiquitous molecule and widely distributed in nature, with functional activity occurring in unicellular organisms, plants, fungi and animals. In most vertebrates, including humans, melatonin is synthesized primarily in the pineal gland and is regulated by the environmental light/dark cycle via the suprachiasmatic nucleus. Pinealocytes function as ‘neuroendocrine transducers’ to secrete melatonin during the dark phase of the light/dark cycle and, consequently, melatonin is often called the ‘hormone of darkness’. Melatonin is principally secreted at night and is centrally involved in sleep regulation, as well as in a number of other cyclical bodily activities. Melatonin is exclusively involved in signaling the ‘time of day’ and ‘time of year’ (hence considered to help both clock and calendar functions) to all tissues and is thus considered to be the body's chronological pacemaker or ‘Zeitgeber’. Synthesis of melatonin also occurs in other areas of the body, including the retina, the gastrointestinal tract, skin, bone marrow and in lymphocytes, from which it may influence other physiological functions through paracrine signaling. Melatonin has also been extracted from the seeds and leaves of a number of plants and its concentration in some of this material is several orders of magnitude higher than its night‐time plasma value in humans. Melatonin participates in diverse physiological functions. In addition to its timekeeping functions, melatonin is an effective antioxidant which scavenges free radicals and up‐regulates several antioxidant enzymes. It also has a strong antiapoptotic signaling function, an effect which it exerts even during ischemia. Melatonin's cytoprotective properties have practical implications in the treatment of neurodegenerative diseases. Melatonin also has immune‐enhancing and oncostatic properties. Its ‘chronobiotic’ properties have been shown to have value in treating various circadian rhythm sleep disorders, such as jet lag or shift‐work sleep disorder. Melatonin acting as an ‘internal sleep facilitator’ promotes sleep, and melatonin's sleep‐facilitating properties have been found to be useful for treating insomnia symptoms in elderly and depressive patients. A recently introduced melatonin analog, agomelatine, is also efficient for the treatment of major depressive disorder and bipolar affective disorder. Melatonin's role as a ‘photoperiodic molecule’ in seasonal reproduction has been established in photoperiodic species, although its regulatory influence in humans remains under investigation. Taken together, this evidence implicates melatonin in a broad range of effects with a significant regulatory influence over many of the body's physiological functions.
Roles of the human Rad51 L1 and L2 loops in DNA binding
Authors: Matsuo Yusuke , Sakane Isao , Takizawa Yoshimasa , Takahashi Masayuki , Kurumizaka Hitoshi
Published: June 2006

The human Rad51 protein, a eukaryotic ortholog of the bacterial RecA protein, is a key enzyme that functions in homologous recombination and recombinational repair of double strand breaks. The Rad51 protein contains two flexible loops, L1 and L2, which are proposed to be sites for DNA binding, based on a structural comparison with RecA. In the present study, we performed mutational and fluorescent spectroscopic analyses on the L1 and L2 loops to examine their role in DNA binding. Gel retardation and DNA‐dependent ATP hydrolysis measurements revealed that the substitution of the tyrosine residue at position 232 (Tyr232) within the L1 loop with alanine, a short side chain amino acid, significantly decreased the DNA‐binding ability of human Rad51, without affecting the protein folding or the salt‐induced, DNA‐independent ATP hydrolysis. Even the conservative replacement with tryptophan affected the DNA binding, indicating that Tyr232 is involved in DNA binding. The importance of the L1 loop was confirmed by the fluorescence change of a tryptophan residue, replacing the Asp231, Ser233, or Gly236 residue, upon DNA binding. The alanine replacement of phenylalanine at position 279 (Phe279) within the L2 loop did not affect the DNA‐binding ability of human Rad51, unlike the Phe203 mutation of the RecA L2 loop. The Phe279 side chain may not be directly involved in the interaction with DNA. However, the fluorescence intensity of the tryptophan replacing the Rad51‐Phe279 residue was strongly reduced upon DNA binding, indicating that the L2 loop is also close to the DNA‐binding site.
HOSTILE TAKEOVER: ANTIUNIONISM AND THE NEOLIBERAL POLITICS OF URBAN SCHOOL REFORM IN NEW YORK
Authors: Anderson Noel
Published: June 2006

Much of the current discourse on public educational reform in the U.S. collapses into concerns over testing and/or school governance. Yet there are neoliberal policies being promoted in the guise of educational reform initiatives that are eroding teacher union gains, particularly in urban centers. This article focuses on a recent conflict between the United Federation of Teachers and Mayor Michael Bloomberg over a fair labor contract in New York City as an illustrative example of the antiteacher union trend taking place in urban education reform efforts in the U.S. The author calls for greater teacher union–community solidarity to recapture public education.