bluuebunny/crossref_metadata_2025_split huggingface dataset:
Meridional Differences in Temporal Resolution
Authors: Schwartz Barry D , Winstead Daniel K , May James G 
Published: January 2007

Previous investigations of temporal resolution have shown that performance is influenced by a number of stimulus parameters. The interstimulus interval needed for accurate two-pulse discrimination has been shown to (i) decrease monotonically with flash duration, luminance, and contrast; and (ii) increase monotonically with the spatial frequency of the target. A signal-detectability two-alternative forced-choice procedure was employed to reexamine the effects of spatial frequency on temporal resolution. Also assessed was the effect of grating orientation on such performance. The results confirm that temporal resolution declines with increases in spatial frequency. Furthermore, temporal resolution was significantly lower when oblique, as opposed to vertical, grating targets were used. This ‘oblique effect’ in temporal resolution was observed only with the highest-spatial-frequency target (15 cycles deg−1), and not with stimuli of lower spatial frequency (0·9 and 3·8 cycles deg−1). These findings suggest that stimulus parameters which elicit greater transient channel activity, as opposed to sustained channel activity, enhance temporal resolution. When transient activity is at a minimum, meridional differences in temporal resolution are likely to be attributable to sustained channel activity.
Effects of Luminance and Contrast on Direction of Ambiguous Apparent Motion
Authors: Anstis Stuart M , Mather George 
Published: January 2007

A study is reported of the role of luminance and contrast in resolving ambiguous apparent motion (AM). Different results were obtained for the short-range (SR) and the long-range (LR) motion-detecting processes. For short-range jumps (7.5 min arc), the direction of ambiguous AM depended on brightness polarity, with AM only from white to white and from black to black. But for larger jumps, or when an interstimulus interval (ISI) was introduced, AM was less dependent on polarity, with white often jumping to black and black jumping to white. Two potential AMs were pitted against each other, one carried by a light stimulus and the other by a dark stimulus. The stimulus whose luminance differed most from the uniform surround captured the AM. Visual response to luminance was linear, not logarithmic. When the stimulus was modified to give continuous AM in one direction it was followed by a negative aftereffect of motion only when the spatial displacement was 1 min arc. A larger displacement (10 min arc) gave good AM but no motion aftereffect. Thus only short-range motion adapts motion-sensitive channels.
Finding Locations in the Environment: The Map as Mediator
Authors: Warren David H , Scott Teres E , Medley Cindy 
Published: January 2007

When an observer (O) uses a map (M) whose orientation does not correspond to the orientation of the environment (E) in which performance occurs, substantial errors occur: these are called map alignment effects. Much of the prior research on map/environment (M/E) alignment has involved maps of simple paths, although alignment effects have also been demonstrated for you-are-here (YAH) maps. A study is reported in which simple YAH maps were used to test the hypothesis that errors with misaligned maps would fall into categories predictable from the application of inappropriate cognitive operations to the misaligned maps, as demonstrated earlier by Rossano and Warren. Further, performance under conditions of M/E misalignment was compared with performance under map/observer (M/O) misalignment, the situation in which the map is sideways or upside-down with respect to the observer. The major hypothesis was supported: predictable errors occurred under conditions of M/E misalignment. Errors under conditions of M/O misalignment were significantly smaller. Furthermore, when given the choice of using M/E or M/O alignment, each at the expense of the other, the overwhelming choice was to retain M/E rather than M/O alignment. This pattern of results occurred even when environmental features were represented by words rather than by lines and shapes on the map. The results underscore the robustness of map alignment effects.
Heme binding inhibits the fibrillization of amyloidogenic apomyoglobin and determines lack of aggregate cytotoxicity
Authors: Iannuzzi Clara , Vilasi Silvia , Portaccio Marianna , Irace Gaetano , Sirangelo Ivana 
Published: January 2007

AbstractMyoglobin is an α‐helical globular protein containing two highly conserved tryptophanyl residues at positions 7 and 14 in the N‐terminal region. The double W/F replacement renders apomyoglobin highly susceptible to aggregation and amyloid‐like fibril formation under physiological conditions. In this work we analyze the early stage of W7FW14F apomyoglobin aggregation following the time dependence of the process by far‐UV CD, Fourier‐transform infrared (FTIR) spectroscopy, and heme‐binding properties. The results show that the aggregation of W7FW14F apomyoglobin starts from a native‐like globin state able to bind the prosthetic group with spectroscopic properties similar to those observed for wild‐type apoprotein. Nevertheless, it rapidly aggregates, forming amyloid fibrils. However, when the prosthetic group is added before the beginning of aggregation, amyloid fibrillization is inhibited, although the aggregation process is not prevented. Moreover, the apomyoglobin aggregates formed in these conditions are not cytotoxic differently from what is observed for all amyloidogenic proteins. These results open new insights into the relationship between the structure adopted by the protein into the aggregates and their ability to trigger the impairment of cell viability.
Symptoms of asthma and atopic disorders in preschool children: prevalence and risk factors
Authors: Wong G. W. K. , Leung T. F. , Ma Y. , Liu E. K. H. , Yung E. , Lai C. K. W. 
Published: January 2007

SummaryBackground
Published epidemiological data suggested that asthma and allergies may be increasing in preschool children. Identification of the risk factors is important for planning possible early intervention to prevent asthma. This study was designed to measure the prevalence of, and risk factors for, asthma and atopic disorders in preschool children from Hong Kong.Methods
Children aged 2–6 years living in Hong Kong were recruited through the local nurseries and kindergartens for this study to ascertain the presence of symptoms of asthma and various possible risk factors. The parental questionnaire was developed based on the International Study of Asthma and Allergies in Childhood questionnaire.Results
A total of 3089 children (1506 boys) from 14 nurseries and kindergartens participated in this study. The prevalence of wheeze ever and current wheeze were 16.7% and 9.3%. Two hundred and thirty‐four subjects were born in mainland China and migrated to Hong Kong subsequently. When compared with children born and raised in Hong Kong, children born in mainland China had significantly lower prevalence of current wheeze (3.4% vs. 9.6%, P<0.01). Two environmental factors in the first year of life were associated with wheezing attacks within the last 12 months. They were the use of foam pillow (Odds ratio: 1.45; 95% Confidence interval: 1.04–2.00) and the use of gas as cooking fuel (1.68; 1.03–2.75). Frequent use of paracetamol was also associated with wheezing attack in the past 12 months.Conclusions
This study confirms the high prevalence of symptoms of atopic disorders in preschool children from Hong Kong. Early environmental exposure factors are important determinants of subsequent development of asthma symptoms in the preschool years. Further studies are needed to evaluate the possible pathogenetic role of the identified risk factors.
Safety of anti‐immunoglobulin E therapy with omalizumab in allergic patients at risk of geohelminth infection
Authors: Cruz A. A. , Lima F. , Sarinho E. , Ayre G. , Martin C. , Fox H. , Cooper P. J. 
Published: January 2007

SummaryBackground
Although the role of immunoglobulin E (IgE) in immunity against helminth parasites is unclear, there is concern that therapeutic antibodies that neutralize IgE (anti‐IgE) may be unsafe in subjects at risk of helminth infection.Objective
We conducted an exploratory study to investigate the safety of omalizumab (anti‐IgE) in subjects with allergic asthma and/or perennial allergic rhinitis at high risk of intestinal helminth infection. The primary safety outcome was risk of infections with intestinal helminths during anti‐IgE therapy.Methods
A randomized, double‐blind, placebo‐controlled trial was conducted in 137 subjects (12–30 years) at high risk of geohelminth infection. All subjects received pre‐study anthelmintic treatment, followed by 52 weeks' treatment with omalizumab or placebo.Results
Of the omalizumab subjects 50% (34/68) experienced at least one intestinal geohelminth infection compared with 41% (28/69) of placebo subjects [odds ratio (OR) 1.47, 95% confidence interval (CI) 0.74–2.95, one‐sided P=0.14; OR (adjusted for study visit, baseline infection status, gender and age) 2.2 (0.94–5.15); one‐sided P=0.035], providing some evidence for a potential increased incidence of geohelminth infection in subjects receiving omalizumab. Omalizumab therapy was well tolerated, and did not appear to be associated with increased morbidity attributable to intestinal helminths as assessed by clinical and laboratory adverse events, maximal helminth infection intensities and additional anthelmintic requirements. Time to first infection (OR 1.30, 95% CI 0.79–2.15, one‐sided P=0.15) was similar between treatment groups. Infection severity and response to anthelmintics appeared to be unaffected by omalizumab therapy.Conclusions
In this exploratory study of allergic subjects at high risk of helminth infections, omalizumab therapy appeared to be safe and well tolerated, but may be associated with a modest increase in the incidence of geohelminth infection.
Galectin‐3 and CD44v6 positivity by RT‐PCR method in fine needle aspirates of benign thyroid lesions
Authors: Mateša N. , Šamija I. , Kusić Z. 
Published: January 2007

Objective:  To investigate whether the presence of macrophages and Hürthle cells (HC) in benign thyroid lesions could explain the false‐positive expression of galectin‐3 and CD44v6 detected by reverse transcriptase‐polymerase chain reaction (RT‐PCR).Methods:  For galectin‐3 and CD44v6, RT‐PCR was performed on RNA isolated from aspirates obtained by ultrasound guided fine needle aspiration cytology (FNAC) from 123 patients with benign thyroid lesions. The results of RT‐PCR analysis were evaluated against the definitive FNAC diagnosis.Results:  Galectin‐3 expression was found in 29% follicular adenoma (FA), 26% Hashimoto thyroiditis (HT), and in 24% nodular goitre (NG). We found a statistically significant relationship between the presence of macrophages and galectin‐3 positivity in NG and HT samples (P < 0.0001 and P = 0.0087 respectively). We found a statistically significant (P = 0.0219) relationship between the presence of HC and galectin‐3 positivity in HT and a tendency of such a relationship (P = 0.0838) in NG.CD44v6 expression was found in 29% FA, 33% HT and in 18% NG. We found a statistically significant relationship between the presence of HC and positive expression of CD44v6 in NG (P = 0.0003) and a strong tendency of such a relationship in HT (P = 0.0571). We did not find a statistically significant relationship between the presence of macrophages and CD44v6 positivity.In FA, we did not find a statistically significant relationship between the presence of macrophages or HC and galectin‐3 or CD44v6 positivity.Conclusion:  Our results suggest that the presence of macrophages and/or HC may explain the positive expression of galectin‐3 and CD44v6 detected by RT‐PCR in HT and NG cytological samples.
The retrocyclin analogue RC‐101 prevents human immunodeficiency virus type 1 infection of a model human cervicovaginal tissue construct
Authors: Cole Amy L. , Herasimtschuk Anna , Gupta Phalguni , Waring Alan J. , Lehrer Robert I. , Cole Alexander M. 
Published: January 2007

SummaryRetrocyclins are cyclic antimicrobial peptides that exhibit potent activity towards a broad range of primary and laboratory‐adapted strains of human immunodeficiency virus type 1 (HIV‐1) in vitro. The current study shows that RC‐101, an analogue of retrocyclin, prevented HIV‐1 infection in an organ‐like construct of human cervicovaginal tissue and retained full activity in the presence of vaginal fluid. The peptide remained within the cervicovaginal tissues throughout the 9‐day incubation period without altering tissue viability, inducing damage or inducing the release of inflammatory cytokines. Collectively, these data support the potential development of RC‐101 as a topical microbicide to prevent HIV‐1 infection and transmission.
Minimizing errors in identifying Lévy flight behaviour of organisms
Authors: SIMS DAVID W. , RIGHTON DAVID , PITCHFORD JONATHAN W. 
Published: January 2007

Summary

Lévy flights are specialized random walks with fundamental properties such as superdiffusivity and scale invariance that have recently been applied in optimal foraging theory. Lévy flights have movement lengths chosen from a probability distribution with a power‐law tail, which theoretically increases the chances of a forager encountering new prey patches and may represent an optimal solution for foraging across complex, natural habitats.
An increasing number of studies are detecting Lévy behaviour in diverse organisms such as microbes, insects, birds, and mammals including humans. A principal method for detecting Lévy flight is whether the exponent (µ) of the power‐law distribution of movement lengths falls within the range 1 < µ ≤ 3. The exponent can be determined from the histogram of frequency vs. movement (step) lengths, but different plotting methods have been used to derive the Lévy exponent across different studies.
Here we investigate using simulations how different plotting methods influence the µ‐value and show that the power‐law plotting method based on 2k (logarithmic) binning with normalization prior to log transformation of both axes yields low error (1·4%) in identifying Lévy flights. Furthermore, increasing sample size reduced variation about the recovered values of µ, for example by 83% as sample number increased from n = 50 up to 5000.
Simple log transformation of the axes of the histogram of frequency vs. step length underestimated µ by c.40%, whereas two other methods, 2k (logarithmic) binning without normalization and calculation of a cumulative distribution function for the data, both estimate the regression slope as 1 − µ. Correction of the slope therefore yields an accurate Lévy exponent with estimation errors of 1·4 and 4·5%, respectively.
Empirical reanalysis of data in published studies indicates that simple log transformation results in significant errors in estimating µ, which in turn affects reliability of the biological interpretation. The potential for detecting Lévy flight motion when it is not present is minimized by the approach described. We also show that using a large number of steps in movement analysis such as this will also increase the accuracy with which optimal Lévy flight behaviour can be detected.
A disparity in the association of asthma, rhinitis, and eczema with allergen‐specific IgE between Finnish and Russian Karelia
Authors: Pekkarinen P. T. , Von Hertzen L. , Laatikainen T. , Mäkelä M. J. , Jousilahti P. , Kosunen T. U. , Pantelejev V. , Vartiainen E. , Haahtela T. 
Published: January 2007

Background:  A substantial variation in the association of asthma, rhinitis and eczema with elevated serum allergen‐specific immunoglobulin E (sIgE) levels between different populations has been reported. Here, we wanted to clarify whether these proportions are different in Finnish and Russian Karelia, and compared the ability of questionnaires, skin prick tests (SPT) and sIgE measurements to detect atopic conditions in these adjacent areas with different living conditions.Methods:  Randomly selected schoolchildren, aged 6–16 years, and their mothers from Finland (n = 344 children, 344 mothers) and Russia (427 and 284 respectively) participated. SPTs and sIgE measurements to common inhalant and food allergens were performed. The occurrence of asthma, rhinitis, eczema and related symptoms was assessed with an International Study of Asthma and Allergies in Childhood‐based questionnaire. Correlation between SPT and sIgE was estimated using the Spearman correlation coefficient.Results:  The rate of positive sIgE results was significantly higher in Finland among both mothers and children. Seventy‐seven per cent of Finnish children and 43% of Russian children with asthma were sIgE positive. The respective figures for hay fever were 94% and 67%, and for eczema 68% and 41%. This discrepancy was similar but of lower magnitude among mothers. The overall occurrence of asthma, rhinitis and eczema was very low in Russian Karelia. The correlation between SPT and sIgE results was generally good.Conclusion:  Asthma, rhinitis and eczema in Russian Karelia are not only rare but also, to a large extent, have no sIgE component. Therefore, the ability of questionnaires to detect sIgE‐mediated atopic conditions in this area of Russia is poor.
Evolution of viviparity in warm‐climate lizards: an experimental test of the maternal manipulation hypothesis
Authors: JI X. , LIN C.‐X. , LIN L.‐H. , QIU Q.‐B. , DU Y. 
Published: January 2007

AbstractThe maternal manipulation hypothesis for the evolution of reptilian viviparity has been claimed to apply to any situation where gravid females are able to maintain body temperatures different from those available in external nests, but empirical data that support this hypothesis are very limited. Here, we tested this hypothesis using gravid females of a warm‐climate lizard, Mabuya multifasciata, by subjecting them to five thermal regimes for the whole gestation period. We found gravid females selected lower body temperatures and thermoregulated more precisely than did nongravid females. Offspring produced in different treatments differed in head size, limb length and sprint speed, but not in overall body size or mass. Variation in morphological traits of offspring was induced primarily by extreme temperatures. Sprint speed of offspring was more likely affected by the mean but not by the variance of gestation temperatures. Gravid females maintained more stable body temperatures than did nongravid females not because these temperatures resulted in the optimization of offspring phenotypes but because the range of temperatures optimal for embryonic development was relatively narrow. Our data conform to the main predictions from the maternal manipulation hypothesis that females should adjust thermoregulation during pregnancy to provide optimal thermal conditions for developing embryos and that phenotypic traits forged by maternal thermoregulation should enhance offspring fitness.
IgE‐bearing Cells in Bronchoalveolar Lavage Fluid and Allergen‐specific IgE Levels in Sera from RAO‐affected Horses
Authors: Künzle F. , Gerber V. , Van Der Haegen A. , Wampfler B. , Straub R. , Marti E. 
Published: January 2007

SummaryRecurrent airway obstruction (RAO) is a common condition in stabled horses characterized by small airway inflammation, airway neutrophilia and obstruction following exposure of susceptible horses to mouldy hay and straw and is thus regarded as a hypersensitivity reaction to mould spores. However, the role of immunoglobulin E antibodies (IgE) in the pathogenesis of RAO is unclear. We hypothesized that the number of cells with receptor‐bound IgE in bronchoalveolar lavage fluid (BALF) and IgE levels in serum would be higher in RAO‐affected than in healthy horses living in the same environment. Therefore, IgE‐positive (+) cells were identified by immunocytochemistry on cytospins from BALF and counted. IgE levels against the mould extractsAspergillus fumigatus(Asp. f.) andAlternaria alternata(Alt. a.) and the recombinant mould allergenAspergillus fumigatus8 (rAsp f 8) were measured by enzyme‐linked immunosorbent assay (ELISA) in the sera of seven RAO‐affected and 22 clinically healthy mature horses housed in the same conventional stable environment. After correcting for the number of neutrophils, there were no significant differences in IgE+ cells on cytospins from BALF between both groups of horses (5% versus 7%,P > 0.1). Serum IgE levels against the mould extracts were significantly higher in RAO‐affected than in clinically healthy horses [median = 119 versus 66 relative ELISA units (REU),P < 0.05]. Furthermore, significantly more RAO‐affected than healthy horses had detectable serum IgE against the recombinant allergen rAsp f 8 (4/7 and 3/22, respectively,P < 0.05). Age had no significant effect on BALF cell ratios or on specific serum IgE levels. These results show that high IgE levels against mould antigens are associated with RAO under controlled environmental conditions but ranges of mould‐specific serum IgE levels overlapped too much between diseased and clinically healthy animals to be of any diagnostic value. Further studies are needed to assess whether IgE‐mediated reactions contribute to the pathogenesis of RAO.
Microbiological Screening Test Validation for Detection of Tylosin Excretion in Milk of Cows with Low and High Somatic Cell Counts
Authors: Litterio N. J. , Calvinho L. F. , Flores M. M. , Tarabla H. D. , Boggio J. C. 
Published: January 2007

SummaryAntibiotic residues in milk above tolerance levels interfere with dairy product processing and pose potential health risks to consumers. Residue avoidance programmes include, among other components, the observance of withdrawal times indicated in label instructions. Persistence of antibiotics in milk following treatment is influenced by drug, dosage, route of administration, body weight and mammary gland health status. Compositional changes that take place during intramammary infection (IMI) can affect antibiotic excretion in milk, thus modifying milk withdrawal time. The objectives of this study were to validate sensitivity and specificity of a qualitative microbiological method (Charm®AIM‐96) to detect tylosin in bovine composite milk and to determine the influence of subclinical IMI in tylosin excretion following intramuscular administration. For test validation, two groups of approximately 120 cows were used; one received a single intramuscular injection of tylosin tartrate at a dose of 20 mg/kg, while the other group remained as untreated control. Test sensitivity and specificity were 100% and 94.1% respectively. To determine the influence of subclinical IMI in tylosin excretion, two groups of seven cows, one with somatic cell counts (SCC) ≤250 000 cells/ml and the other with SCC ≥900 000, were administered a single intramuscular injection of tylosin tartrate at a dose of 20 mg/kg. Milk samples were obtained every 12 h for 10 days following treatment. Milk tylosin excretion averaged between 5 and 9 days for cows with low and high SCC respectively (P < 0.0001). Compositional changes in cows with high SCC most likely affect the pharmacokinetic characteristics of tylosin, extending the presence of the antibiotic in milk, thus influencing milk withdrawal times.
Atoxoplasma spp. Infection in Captive Canaries (Serinus canaria)
Authors: Sánchez‐Cordón P. J. , Gómez‐Villamandos J. C. , Gutiérrez J. , Sierra M. A. , Pedrera M. , Bautista M. J. 
Published: January 2007

SummaryClinical signs, histopathological and ultrastructural findings associated with Atoxoplasma spp. natural infection in captive canaries (Serinus canaria) are described. Intracytoplasmic Atoxoplasma‐like protozoa were found in the liver and lung. In the liver, protozoa were found in hepatocytes and Kupffer's cells and were associated with granulomatous hepatitis and a marked bile duct hyperplasia. An usual finding was the presence of infected mononuclear cells adhered to the endothelium of the blood vessels in lung. The diagnosis was confirmed by ultrastructural examination of reprocessed paraffin‐embedded tissues.