bluuebunny/crossref_metadata_2025 huggingface dataset:
The Sphingosine-1-Phosphate (S1P) Lysophospholipid Receptor S1P3 Regulates MAdCAM-1+ Endothelial Cells in Splenic Marginal Sinus Organization
Authors: Girkontaite Irute , Sakk Vadim , Wagner Martin , Borggrefe Tilman , Tedford Kerry , Chun Jerold , Fischer Klaus-Dieter
Published: December 2004

Marginal zones (MZs) are microdomains in the spleen that contain various types of immune cells, including MZ B cells, MOMA1+ metallophilic macrophages, and mucosal addressin cell adhesion molecule 1 (MAdCAM-1)+ endothelial cells. MAdCAM-1+ and MOMA1+ cells line the sinus, that separates MZs from splenic follicles. Here we show that a receptor for the lysophospholipid sphingosine-1-phosphate (S1P), S1P3, is required for normal numbers of splenic immature and MZ B cells, and for S1P-induced chemotaxis of MZ B cells. S1P3 is also essential for proper alignment of MOMA1+ macrophages and MAdCAM-1+ endothelial cells along the marginal sinus. The lack of cohesion of the marginal sinus in S1P3−/− mice affects MZ B cell functions, as wild-type (WT) MZ B cells migrate more into S1P3−/− follicles than into WT follicles after treatment with lipopolysaccharide. Additionally, short-term homing experiments demonstrate that WT MZ B cells home to the S1P3−/− spleen in increased numbers, suggesting a role for the marginal sinus in regulating MZ B cells numbers. Moreover, S1P3−/− mice are defective in mounting immune responses to thymus-independent antigen type 2 due to defects in radiation-resistant cells in the spleen. These data identify lysophospholipids and the S1P3 receptor as essential regulators of the MZ sinus and its role as a barrier to the follicle.
Evaluating Markers for Selecting a Patient's Treatment
Authors: Song Xiao , Pepe Margaret Sullivan
Published: December 2004

SummarySelecting the best treatment for a patient's disease may be facilitated by evaluating clinical characteristics or biomarker measurements at diagnosis. We consider how to evaluate the potential impact of such measurements on treatment selection algorithms. For example, magnetic resonance neurographic imaging is potentially useful for deciding whether a patient should be treated surgically for Carpal Tunnel Syndrome or should receive less‐invasive conservative therapy. We propose a graphical display, the selection impact (SI) curve that shows the population response rate as a function of treatment selection criteria based on the marker. The curve can be useful for choosing a treatment policy that incorporates information on the patient's marker value exceeding a threshold. The SI curve can be estimated using data from a comparative randomized trial conducted in the population as long as treatment assignment in the trial is independent of the predictive marker. Estimating the SI curve is therefore part of a post hoc analysis to determine whether the marker identifies patients that are more likely to benefit from one treatment over another. Nonparametric and parametric estimates of the SI curve are proposed in this article. Asymptotic distribution theory is used to evaluate the relative efficiencies of the estimators. Simulation studies show that inference is straightforward with realistic sample sizes. We illustrate the SI curve and statistical inference for it with data motivated by an ongoing trial of surgery versus conservative therapy for Carpal Tunnel Syndrome.
Methods for the Statistical Analysis of Binary Data in Split‐Cluster Designs
Authors: Donner Allan , Klar Neil , Zou Guangyong
Published: December 2004

Summary Split‐cluster designs are frequently used in the health sciences when naturally occurring clusters such as multiple sites or organs in the same subject are assigned to different treatments. However, statistical methods for the analysis of binary data arising from such designs are not well developed. The purpose of this article is to propose and evaluate a new procedure for testing the equality of event rates in a design dividing each of k clusters into two segments having multiple sites (e.g., teeth, lesions). The test statistic proposed is a generalization of a previously published procedure based on adjusting the standard Pearson chi‐square statistic, but can also be derived as a score test using the approach of generalized estimating equations.
Using Image and Curve Registration for Measuring the Goodness of Fit of Spatial and Temporal Predictions
Authors: Reilly Cavan , Price Phillip , Gelman Andrew , Sandgathe Scott A.
Published: December 2004

SummaryConventional measures of model fit for indexed data (e.g., time series or spatial data) summarize errors iny, for instance by integrating (or summing) the squared difference between predicted and measured values over a range ofx. We propose an approach which recognizes that errors can occur in thex‐direction as well. Instead of just measuring the difference between the predictions and observations at each site (or time), we first “deform” the predictions, stretching or compressing along thex‐direction or directions, so as to improve the agreement between the observations and the deformed predictions. Error is then summarized by (a) the amount of deformation inx, and (b) the remaining difference inybetween the data and the deformed predictions (i.e., the residual error inyafter the deformation). A parameter, λ, controls the tradeoff between (a) and (b), so that asλ→∞no deformation is allowed, whereas forλ= 0the deformation minimizes the errors iny. In some applications, the deformation itself is of interest because it characterizes the (temporal or spatial) structure of the errors. The optimal deformation can be computed by solving a system of nonlinear partial differential equations, or, for a unidimensional index, by using a dynamic programming algorithm. We illustrate the procedure with examples from nonlinear time series and fluid dynamics.
OPTIMAL PRICING AND QUALITY CHOICE WHEN INVESTMENT IN QUALITY IS IRREVERSIBLE
Authors: Pennings Enrico
Published: December 2004

This paper examines the price and quality choice of a single product, risk‐neutral monopolist who can delay irreversible investments required for market entry. It is shown that the price and quality she chooses at entry increase with uncertainty about the size of future demand. In a Stackelberg leader‐follower game, the leader and follower pre‐commit immediately up to a certain level of uncertainty. In this case the leader produces the higher quality good. When uncertainty is higher than this threshold, the follower will wait and enter the market later with a higher quality good.
From Family Wage to Parental Leave: The Changing Relationship between Arbitration and the Family
Authors: Whitehouse Gillian
Published: December 2004

From the establishment of a ‘family wage’ for men in the early 1900s through to ongoing test cases over parental leave in the early 2000s, the arbitration system has played a central role in shaping the policy framework affecting families and the intersection of market and domestic labour. The institutionalisation of a needs-based family wage for men under ‘new protectionism’ in early twentieth century Australia placed the arbitration system at the centre of numerous policy debates and reinforced pre-existing notions of the male breadwinner family. Abandonment of the family wage and the protectionist environment, along with changing social values and labour force patterns, have recast the relationship between arbitration and the family over the course of the twentieth century. Nevertheless, the wage setting system continues to sustain a contemporary variant of the male breadwinner model and is playing a pivotal role in shaping parental employment rights into the twenty-first century.
“INTERNAL THECAE” OF EUNOTIA SOLEIROLII (BACILLARIOPHYCEAE): DEVELOPMENT, STRUCTURE AND FUNCTION AS RESTING SPORES1
Authors: Hans‐Adolf  , Stosch Von , Fecher Klaus
Published: December 2004

The “double thecae” or “internal septa” of Eunotia soleirolii (Kütz.) Rabenh, are shown to represent the thecae of resting spores, as characterized by their physiology, as well as morphology. They differ from all resting spores of centric diatoms by the formation of both their valves as a result of unequal cell divisions; and, from the majority of centric spores by the presence of several girdle bands in both their thecae. Spore formation can be induced by high or low pH, high temperature (24 C), and iron, silica, phosphate or nitrate deficiencies, whereas low temperatures defer it. Spores do not germinate directly, but dormancy can be removed by dark treatments (–2 to 15 C) for a minimum of 4–5 wk. Longer dark treatments result in higher germination rates. At 15 C, a minimum of 2 mo is required and 4 mo is better. Heat treatments (27–42 C) are ineffective, but may shorten the dormancy‐breaking subsequent cold period. Instances of secondary dormancy, as well as relative dormancy, were observed. Germination usually occurs in the light between 2 and 21 C. An equal division of the spore is followed by unequal divisions of both new cells with only the two resulting large cells being viable. The experiences in the laboratory aided the discovery of stages of spore germination in nature.
SYNARTHROPHYTON, A NEW GENUS OF CORALLINACEAE (CRYPTONEMIALES, RHODOPHYTA) FROM THE SOUTHERN HEMISPHERE1
Authors: Townsend Roberta A.
Published: December 2004

Synarthrophyton gen. nov. is described based on southern Australian material of Melobesia patena Hooker fils & Harvey, which shows features intermediate between Mesophyllum Lemoine and Lithothamnium Philippi. It has the thin‐walled rounded epithallial cells and coaxial hypothallium characteristic of Mesophyllum and the type of procarp and male structures common to Lithothamnium. Synarthrophyton is unique within the subfamily Melobesioideae (J. E. Areschoug) Yendo because it displays secondary pit connections. Details of the vegetative and reproductive morphology of S. patena (Hooker fils. & Harvey) comb. nov. are given and its taxonomic position in the Corallinaceae Lamouroux discussed.
OSMOREGULATION IN THE MARINE DIATOM CYLINDROTHECA FUSIFORMIS1
Authors: Paul John S.
Published: December 2004

A mechanism for the regulation of internal osmolarity in the diatoms (Bacillariophyta) was investigated using the intertidal lestuarian pennate diatom, Cylindrotheca fu‐siformis Reimann & Lewin. The intracellular pools of the free sugar, mannose, and its respective polymer, poly‐mannose, were found to be in a dynamic equilibrium which rapidly responds to changes in external osmotic pressure. Increasing the salinity shifts the steady state in the direction of free mannose, while decreasing the salinity stimulates polymerization of the free mannose to its polysaccharide. The mechanism requires a response of certain key enzymes to osmotic pressure rather than to levels of any particular ion since increasing the external osmolarity with an organic solute (sorbitol) was as effective in eliciting a response as using inorganic ions.
SHORT‐TERM RESPONSES OF NUTRIENT‐DEFICIENT ALGAE TO NUTRIENT ADDITION1
Authors: Healey F. Patrick
Published: December 2004

Changes in net photosynthesis, dark respiration, ATP content, and some other aspects of composition were measured following phosphate or ammonium addition to cultures of the green alga Scenedesmus quadricauda (Turp.) Bréb. deficient in phosphorus or nitrogen. The deficient nutrient was rapidly taken up. Light‐saturated net photosynthesis was depressed below the pre‐addition rate during nutrient uptake and did not increase markedly above that rate until several hours after uptake was complete. Dark respiration, on the other hand, was markedly stimulated during uptake of the deficient nutrient and to a lesser extent after uptake was complete. Phosphate addition to P‐deficient cells caused a large increase in the ATP content within 2–4 h of addition, whereas ammonium addition to N‐deficient cells caused much less or no increase in ATP content. Short‐term enrichment experiments to detect nutrient limitations are evaluated in the light of these and similar results taken from the literature. The available evidence shows that photosynthetic responses cannot reliably be used in short‐term enrichments but changes in respiration or ATP content may be useful in certain circumstances.
PHOSPHATE‐LIMITED GROWTH KINETICS OFSELENASTRUM CAPRICORNUTUM(CHLOROPHYCEAE)1
Authors: Brown Edward J. , Button Don K.
Published: December 2004

Most theoretical studies of phytoplankton growth in aquatic environments assume that relative nutrient utilization abilities regulate species composition. The steady‐state phosphate‐limited growth kinetics ofSelenastrum capricornutumPrintz were examined using continuous cultures to characterize the green alga's ability to compete for orthophosphate (Pi) when Pi limits growth. The maximal specific growth rate forSelenastrumat 20 C was 1.20 day−1, and the concentration where half maximal growth rate occurs was 40 nM Pi. There was an apparent threshold of 10 nM Pi. Cell yields varied inversely with growth rate; thus ability to utilize Pi could not be characterized in terms of the Monod half‐saturation constant and maximal growth rate. Instead, we computed the Pi affinity from steady‐state flux vs. external Pi concentrations. This affinity was 2.8 l·mg dry wt−1· day−1forSelenastrum.Kinetic evidence from this study suggests thatSelenastrumwill not be growth competitive with some other common aquatic heterotrophs and autotrophs when Pi limits microbial growth in lakes.
SEXUAL REPRODUCTION IN THE TOXIC DINOFLAGELLATEGONYAULAX MONILATA1
Authors: Walker Linda M. , Steidinger Karen A.
Published: December 2004

The sexual cycle ofGonyaulax monilataHowell was observed in stationary cultures and in nitrogen‐deficient medium. The armored, isogamous gametes fuse in a characteristic manner with cingula at oblique angles. Nuclear fusion lags slightly behind cytoplasmic fusion. The zygote enlarges for several days. The dark, double‐flagellated planozygote encysts within 1–3 wk. Early hypnozygotes are round to ovoid and contain lipid and one or two large golden‐yellow globules. As the hypnozygote matures, the globules become smaller and the cytoplasm darkens and pulls from the wall. All cysts examined contained only one nucleus. A very dark, uninucleate post‐hypnozygotic cell escapes through an archeopyle and within 24 h divides into daughter cells which divide in 24–48 h forming a small chain. The production of thick walled zygates in culture implies that such resting stages in marine sediments could serve as a source stock for blooms. This species causes toxic red tides and the existence of benthic “seed beds” consisting of hypnozygotes is now plausible.
EFFECT OF SILICATE LIMITATION ON VALVE MORPHOLOGY IN THALASSIOSIRA AND COSCINODISCUS (BACILLARIOPHYCEAE)1
Authors: Booth Beatrice , Harrison Paul J.
Published: December 2004

Coscinodiscus radiatus Ehrenb. and Thalassiosira eccentrica (Ehrenb.) Cleve were grown in a silicate‐limited chemostat at silicate concentrations below 1 μg‐atoms · l−1. The resulting abnormal valves of C. radiatus lacked a thickened ring around the foramina; their pore membranes were thinner and their loculi shallower than those in normal cells. Abnormal valves of T. eccentrica had a fasciculate areolae pattern; they lacked a silica covering over the foramina and some tangential areolae walls. Neither abnormal valve could be termed a new species.
Integration, validation and point spacing optimisation of digital elevation models
Authors: Buckley Simon J. , Mitchell Harvey L.
Published: December 2004

In recent years, collection and processing techniques for creating digital elevation models (DEMs; defined here as being surfaces composed of regular or irregular point data, without distinction) have advanced rapidly, allowing terrain to be represented with greater detail and accuracy. Accordingly, the amount of terrain data in existence proliferates as the resolution of sensors improves and acquisition costs lower. It is therefore becoming common for several models to cover any given area as higher accuracy or revised surveys are performed. Such coinciding data‐sets allow improvement to the terrain depiction by integration techniques which merge and validate the individual DEMs. However, amalgamation of all available points is impractical, as errors and differences between the DEMs degrade the accuracy of the merged model, and the data volume may result in heavy oversampling. Consequently, this paper develops a DEM integration method by detailing the error budgets of individual and fused terrain models, then describing the merging procedure. Initially, comparison of the input surfaces is performed to isolate differences. Next, objects on the terrain surface are optionally removed before a surface matching algorithm is employed to detect and overcome systematic effects. Finally, the models are intelligently merged and the point distribution optimised to achieve an efficient surface representation. The methodology was used to integrate a dense airborne laser scanning DEM with sparser photogrammetric data encompassing a larger area. Surface matching proved to be vital, recovering a previously unidentifiable bias between the input DEMs, improving the accuracy of the fused surface.
Optimising the accuracy of a low‐cost photogrammetric motion study system
Authors: Chong Albert K.
Published: December 2004

Generally, a low‐cost image‐based motion study system consists of a set of two or more video imaging cameras and a set of object space control targets. The control targets are required to provide for the computation of exterior parameters of the video frames of objects in motion. Subsequently, the computed exterior orientation parameters are used to compute the position of the motion targets. In general, the accuracy of the motion data is dependent largely on the accuracy of the 3D coordinates of the control targets, the computed camera and lens parameters and the frame rate of the camera. Obviously, it is difficult to improve the frame rate of a low‐cost camera; however, the other factors may be optimised analytically. Optimising the accuracy of the control targets is a straightforward process and is discussed briefly in the paper. Optimising the computed camera and lens parameters was the main focus of the research. Consequently, the paper provides the detail of the developed optimising technique. The results show that an optimal principal distance and other lens parameters can be determined by analysing the error of a set of highly accurate object distances. The evaluation shows that the accuracy of the video motion study system can be improved by as much as six times or a reduction of scaling error from 1·06 to 1·01.
Right‐Angle Rooftop Polygon Extraction in Regularised Urban Areas: Cutting the Corners
Authors: Croitoru A. , Doytsher Y.
Published: December 2004

Rapid urban development is achieved in some areas by the application of industrialized construction techniques. This approach creates extensive ‘‘regularised’’ urban areas, which are governed by a small set of building models. This paper describes a scheme for building rooftop extraction from aerial and high resolution satellite imagery that makes use of the characteristics of regularised urban areas. As the scheme is based on a bottom‐up approach, emphasis is put on reducing the number of low‐level features that should be considered during the polygon rooftop extraction. This is achieved with a set of geometric rules, which are defined based on the geometry of the building model. Experiments with real‐world imagery show that this basis provides efficient filtering of the right‐angle corners, thus improving the overall extraction performance.
Three‐Dimensional city model visualisation for real‐time guided museum tours
Authors: Lerma José L. , Vidal Jesús , Portalés Cristina
Published: December 2004

Nowadays, there is a trend to show different kinds of cartographic data (and related information) not only in 2D but also in 3D. Additionally, all the data must be easily accessible through the Internet, interactively, and preferably in real time. All these requirements make the management and visualisation of huge volumes of geographical information complicated, mainly in urban areas. This paper deals with these issues and prepares the reader to overcome them. Furthermore, a methodology is proposed for visualising large 3D city models when photogrammetric data and existing geographical information systems are available. Finally, a real‐time interactive animation is introduced, which provides guided museum tours with the aid of the 3D city model of Valencia.
508. Aloe Descoingsii
Authors: Du Puy David
Published: December 2004

Summary.  Aloe descoingsii Reynolds, the smallest Aloe species in the world, endemic to Madagascar, is described and illustrated. Its history, ecology and conservation status are discussed. Its habitat is shown.
509. Dauphinea Brevilabra
Authors: Hardy David S.
Published: December 2004

Summary.  Dauphinea brevilabra Hedge is a little‐known perennial from Madagascar, first described from specimens growing in the Royal Botanic Garden, Edinburgh. In general it resembles Plectranthus, but has several unique floral characters.
Feature
Authors: Burt Elaine , Banks Chris
Published: December 2004

Sedimentary structures in metamorphosed rocks – surely not? However, it's true, as recent work in the Highlands of Scotland can demonstrate.
Potentiation by Angiotensin II of Spontaneous Excitatory Postsynaptic Currents in Rat Supraoptic Magnocellular Neurones
Authors: Ozaki Y. , Soya A. , Nakamura J. , Matsumoto T. , Ueta Y.
Published: December 2004

The physiological actions of angiotensin II in the supraoptic (SON) and paraventricular nuclei have been widely demonstrated, including the modulation of firing rate and release of arginine vasopressin and oxytocin. Here, we investigated whether angiotensin II modulates synaptic inputs into the SON. To do this, we measured spontaneous excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs) from rat SON neurones in thin slice preparations using the whole‐cell patch‐clamp technique. Angiotensin II reversibly increased the frequency of spontaneous EPSCs in a dose‐related manner without affecting the amplitude, indicating that angiotensin II potentiated EPSCs via a presynaptic mechanism. Angiotensin II‐induced potentiation of EPSCs was unaffected in the presence of tetrodotoxin. On the other hand, angiotensin II did not cause significant effects on IPSCs. The potentiation of EPSCs by angiotensin II was potently suppressed by previous exposure to the angiotensin type 1 (AT1) receptor antagonist, losartan. Our results suggest that angiotensin II potentiates the excitatory synaptic inputs into SON neurones, via the AT1 receptors.
Circulating Ghrelin Levels and Central Ghrelin Receptor Expression are Elevated in Response to Food Deprivation in a Seasonal Mammal (Phodopus sungorus)
Authors: Tups A. , Helwig M. , Khorooshi R. M. H. , Archer Z. A. , Klingenspor M. , Mercer J. G.
Published: December 2004

Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor (GHSR). However, the functional interaction of ligand and receptor is not very well understood. We demonstrate that GHSR mRNA is up‐regulated after food deprivation (48 h) in the hypothalamic arcuate nucleus and ventromedial nucleus of the seasonal Siberian hamster, Phodopus sungorus. This increase is accompanied by a two‐fold elevation of circulating ghrelin concentration. Chronic changes in feeding state imposed by food restriction over a period of 12 weeks during long day‐length induced increased GHSR gene expression, whereas food restriction for 6 weeks had no effect. Phodopus sungorus reveals remarkable seasonal changes in body weight, fat mass and circulating leptin levels. Ghrelin is generally regarded as having opposing effects on appetite and body weight with respect to those exhibited by leptin. However, our study revealed that seasonal adaptations were not accompanied by changes in either GHSR gene expression or circulating ghrelin concentration. Therefore, we suggest that ghrelin only plays a minor role in modulating long‐term seasonal body weight cycles. Our findings imply that ghrelin predominantly acts as a short‐term regulator of feeding.
Estimation of Parameters for a Mathematical Model of Growth Hormone Secretion
Authors: Brown D. , Stephens E. A. , Smith R. G. , Li G. , Leng G.
Published: December 2004

Here, we describe partial calibration of a parsimonious mathematical model of growth hormone (GH) secretion. From first principles, we derived a model of the effects on GH secretion from pituitary somatotrophs of stimulation by GH‐releasing factor (GRF) or GH secretagogue, and of inhibition by somatostatin. We obtained a concise model by collapsing the many processes of the signal transduction cascade into a single step broadly reflecting the initial binding of GRF to its receptors. In the model, GH secretion is proportional to the rate of binding of GRF to activatable receptors. Desensitization occurs because of reduction of free receptors/available effector units, and resensitization occurs as those lost are replaced. This replacement is speeded up in the presence of somatostatin, which also inhibits GH secretion by reducing the constant of proportionality between the rate of GH secretion and the rate of GRF binding. We derived simple mathematical equations for the rate of GH secretion and cumulative secretion. Using these, we tested the model against data obtained from experiments performedin vitro, and made it quantitative using rigorous statistical approaches to optimize parameter estimates. The behaviour of the calibrated model matches experimental observations closely.
Role of chloroplast trienoic fatty acids in plant disease defense responses
Authors: Yaeno Takashi , Matsuda Osamu , Iba Koh
Published: December 2004

Trienoic fatty acids (TAs) are the major polyunsaturated fatty acid species in the membrane lipids in plant cells. TAs are crucial for the adaptation to abiotic stresses, especially low‐ or high‐temperature stress. We show that TAs in chloroplast membrane lipids are involved in defense responses against avirulent bacterial pathogens. Avirulent pathogen invasion of plants induces a transient production of reactive oxygen intermediates (ROI), programmed cell death and subsequent disease resistance. The Arabidopsis fad7fad8 mutation, which prevents the synthesis of TAs in chloroplast lipids, caused the reduction in ROI accumulation in leaves inoculated with Pseudomonas syringae pv. tomato DC3000 (avrRpm1). Linolenic acid, the most abundant TA, activated the NADPH oxidase that is responsible for ROI generation. TAs were transferred from chloroplast lipids to extrachloroplast lipids coincident with ROI accumulation after inoculation with Pst DC3000 (avrRpm1). Furthermore, the fad7fad8 mutant exhibited reduced cell death and was compromised in its resistance to several avirulent P. syringae strains. These results suggest that TAs derived from chloroplast lipids play an important role in the regulation of plant defense responses.
A novel reporter for intrachromosomal homoeologous recombination in Arabidopsis thaliana
Authors: Li Liangliang , Santerre‐Ayotte Samuel , Boivin Eric Benoît , Jean Martine , Belzile François
Published: December 2004

A reporter system using engineered introns as recombination substrates in the uidA (GUS) gene has been developed and characterized in Arabidopsis thaliana. The non‐coding nature of the recombination substrate has allowed us to monitor recombination events between duplicated copies of the intron that are either identical (homologous recombination) or harbour sequence polymorphisms (homoeologous recombination). The effects of substrate length and divergence on the frequency of recombination events were examined. A positive correlation between substrate length and somatic recombination frequency was found as the frequency of recombination increased 183‐fold when the recombination substrate was lengthened from 153 to 589 bp. The existence of 11 polymorphisms in a 589‐bp recombination substrate (1.9% sequence divergence) led to an almost 10‐fold reduction in the frequency of recombination. This result demonstrates that relatively modest levels of sequence divergence can substantially reduce the frequency of recombination in plants. A molecular analysis of recombination products revealed that the recombination junctions are more frequent in the central segment of the recombination substrate.
Efficacy of pre‐treatment with lufenuron for the prevention ofMicrosporum canisinfection in a feline direct topical challenge model
Authors: MORIELLO KAREN A. , DEBOER DOUGLAS J. , SCHENKER RUDOLF , BLUM JENIFER L. , VOLK LYNN M.
Published: December 2004

Abstract Oral lufenuron is reportedly an effective treatment for some cats with dermatophytosis. The purpose of this study was to determine if lufenuron, when used as a pre‐treatment prior to challenge exposure, would be protective against the development of infection after the direct topical application of fungal macrocondia (Microsporum canisspores). Three groups (n = 6/group) of juvenile cats were treated with either monthly oral lufenuron (30 or 133 mg/kg) or placebo. After 2 months of treatment, kittens were challenged using 105Microsporum canisspores applied to the skin under occlusion. Cats were examined weekly and the following data collected: Wood's lamp examination; scoring for scale/crust, erythema and induration; lesion size; and the development of satellite lesions. Fungal cultures were performed bi‐weekly. All cats became infected; the infections progressed, and then regressed, in a similar fashion in all groups. There were no consistent statistically significant differences in weekly infection scores between treated and untreated cats throughout the study. Treated cats did not recover faster than untreated cats. We conclude that oral lufenuron at the dosing schedule and conditions used in this study did not prevent dermatophytosis or alter the course of infection by direct topical challenge.
A prospective study of the clinical findings, treatment and histopathology of 44 cases of pyotraumatic dermatitis
Authors: HOLM BIRGIT R. , REST JOAN R. , SEEWALD WOLFGANG
Published: December 2004

Abstract  Pyotraumatic dermatitis (hot spot) is a common clinical syndrome in dogs but there are few prospective scientific studies related to it. The aim of this study was to investigate correlations among clinical pyotraumatic dermatitis, histopathology of the lesions and possible predisposing causes. The relationship of these with breed, age, sex and location of lesion was assessed statistically. A clinical diagnosis of acute pyotraumatic dermatitis was made in 44 privately owned dogs. Males exceeded females (P = 0.0348) and lesions were more common in dogs aged 4 years or less (P < 0.0001). Lesions were most often seen on the cheek, neck and lateral thigh with a significant correlation between breed and site of lesion (P < 0.0001). In 31 cases a possible underlying cause was found or suspected. In contrast to previous studies, no otitis externa was recorded and the study was conducted in an area without endemic fleas. Fourteen breeds were represented of which Rottweiler, German shepherd dog and golden retriever were most common. There was no significant seasonal incidence and no correlation among site of lesion and cause, time of year, age or sex. Histopathologically, the dogs could be separated into four patterns by the presence or absence of eosinophils and/or folliculitis. Eosinophils have not previously been recorded in pyotraumatic dermatitis but were seen in 29 cases. Acute folliculitis was seen in 20 cases. However, no correlation was seen among age, sex, breed, underlying cause or site of lesion and histopathology. Twenty‐seven cases were cultured for bacteria of which 25 grew Staphylococcus intermedius and two were negative.
Seasonal allergic dermatitis in sheep associated with Ctenocephalides and Culicoides bites
Authors: YERUHAM I. , PERL S. , BRAVERMAN Y.
Published: December 2004

Abstract  The clinical, epidemiological and histopathological findings of two pruritic dermatites in sheep in Israel are described. The first type of dermatitis affected mainly young animals with lesions predominantly on the legs. It occurred from March to November, with a peak in June. The second type affected animals of all ages and was mainly on the ventrum. It was sporadic but occurred throughout the year with a peak in October. The morbidity rate of this syndrome reached 4.3% in one flock. The histopathology of both conditions was consistent with an allergic dermatitis. Fleas and midges were collected and identified as Ctenocephalides felis felis and various species of Culicoides. The population density, seasonal activity, geographical distribution and feeding behaviour preferences of the insects and the incidence of the two types of dermatitis suggest that fleas and midges were the causal agents. Flea and midge bite pruritic dermatoses should be considered in the differential diagnosis of sarcoptic and psoroptic mange.
Pemphigus foliaceus in the horse: a retrospective study of 20 cases
Authors: VANDENABEELE SOPHIE I. J. , WHITE STEPHEN D. , AFFOLTER VERENA K. , KASS PHILIP H. , IHRKE PETER J.
Published: December 2004

Abstract  Twenty horses with pemphigus foliaceus were seen over a period of 15 years in a veterinary medical teaching hospital. Breeds seen were seven quarterhorses, five thoroughbreds, three cross‐bred horses, two Arabians and one of each of the following: standardbred, Tennessee walker and warmblood. There was no breed, age or sex predisposition. Nine were mares, ten were geldings and one was a stallion. Ages ranged from 2.5 months to 25 years, with a mean of 8.6 years. Sixteen (80%) of the pemphigus foliaceus horses first exhibited signs between September and February. There was a statistically significant more common occurrence of pemphigus foliaceus during those months. Signs in the four other horses were first noted in March, May or June. Three of those horses were < 13 months of age. Oedema (14/20) and crusts (13/20) were the most common lesions. Pain was present in 9/20 horses, pruritus in 7/20 and pyrexia in 7/20. Follow‐up was available for 13 horses. Five of these horses were euthanased. In three horses the reason for euthanasia was laminitis secondary to treatment. Four horses remained lesion‐free after medication was discontinued. Two horses required maintenance medication and are doing well at the time of writing.
The Vibration Signal and Juvenile Hormone Titers in Worker Honeybees, Apis mellifera
Authors: Schneider Stanley S. , Lewis Lee A. , Huang Zachary Y.
Published: December 2004

We examined the association between the vibration signal and juvenile hormone (JH) titers of honeybees by comparing vibrated recipients and non‐vibrated control workers that had been matched for age, colony of origin, and time of collection. Recipients collected at the moment they received vibration signals (0‐min bees) did not have higher JH titers compared with controls, which suggests that a worker's initial JH level did not influence its likelihood of receiving signals. In contrast, JH titers in workers collected 15–30 min after receiving vibration signals were slightly, but significantly higher than those of controls monitored for the same amount of time. These trends were consistent among colonies, despite the fact that we collected different age ranges of workers and observed pronounced variation in JH titers within and between the 0‐ and 15–30‐min groups of bees. Thus, over a broad age range of workers the vibration signal may contribute to elevated JH levels, and this effect does not occur because recipients have higher titers at the moment they receive signals. Because JH affects response thresholds in honeybees, increased titers elicited by the vibration signal may allow the signal to influence the performance of a variety of tasks in different worker age groups.
Behavioural and Genetic Data Suggest that Bechstein's Bats Predominantly Mate Outside the Breeding Habitat
Authors: Kerth Gerald , Morf Lea
Published: December 2004

Investigating mating systems of species with a cryptic lifestyle often requires a combination of behavioural and genetic data. We used such a combined approach to investigate the mating system of the communal breeding Bechstein's bat (Myotis bechsteinii). Although females of this species are philopatric, gene flow among colonies is high. Gene flow occurs if dispersing males mate within the colony to which they moved. Males could gain local matings by defending resources or females in their breeding habitat. Alternatively, mating may take place at swarming sites, apart from the breeding habitat of the females, where males and females of several colonies meet. Whether or not males defend resources or females in the breeding habitat is of importance for understanding the mating system. Detailed observations of individual foraging and roosting behaviour over 4 yr suggest that males do not defend resources or females to gain matings. Moreover, paternity assignment based on microsatellite data of four complete juvenile cohorts showed that local males fathered less than 25% of the juveniles born in the colony where they settled. Even more striking, none of the males that had immigrated into our study area reproduced with the local females.
Changes in selected serum parameters of broiler chicken fed supplemental chromium
Authors: Króliczewska B. , Zawadzki W. , Dobrzanski Z. , Kaczmarek‐Oliwa A.
Published: December 2004

The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high‐density lipoprotein (HDL) and low‐density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 μg/kg Cr. The supplementation of 500 μg/kg Cr increased body weight, weight gain and feed efficiency (p < 0.05). In addition, supplementation with Cr decreased the serum total cholesterol, LDL cholesterol (p < 0.05), triglycerides (p < 0.05) and glucose (p < 0.05) concentrations whereas serum HDL cholesterol increased. Serum total protein and serum Cr concentration slightly but not significantly increased in both Cr groups. The study suggest that Cr supplementation particularly at 500 μg/kg Cr from Cr yeast can influence on carbohydrate and lipid metabolism of broiler chicken and can be used as additives in animal diet but it still needs more investigations.
Rumen odd and branched chain fatty acids in relation to in vitro rumen volatile fatty acid productions and dietary characteristics of incubated substrates
Authors: Vlaeminck B. , Fievez V. , Van Laar H. , Demeyer D.
Published: December 2004

A first aim of this batch in vitro experiment (21 h) was to use changes in odd and branched chain fatty acid (OBCFA) patterns to suggest shifts in microbial populations, associated with four types of incubated whole dairy cow diets. Principal component analysis suggested higher dietary starch increased the proportion of C15:0 and C17:0, whereas increased neutral detergent fibre content was positively related to anteiso C15:0 concentrations, which is in agreement with the importance of these fatty acids in respectively amylolytic and cellulolytic bacteria. A second aim of the experiment was to relate rumen volatile fatty acid proportions to OBCFA by principal component regression and to compare these relations with predictions based on diet proximate composition. The R2 values achieved for the regressions between acetate, propionate and butyrate, and OBCFA were 79.6%, 86.6% and 84.9% respectively. Moreover, in the current study, predictions of the rumen fermentation pattern showed higher R2 (p < 0.01) when based on OBCFA compared with proximate feed composition. If relations persist in vivo, there could be scope for milk OBCFA to predict the supply of specific rumen nutrients.
The influence of calcium intake on phosphorus digestibility in mature ponies
Authors: van Doorn D. A. , van der Spek M. E. , Everts H. , Wouterse H. , Beynen A. C.
Published: December 2004

Literature data show conflicting results on the effect of feeding high calcium (Ca) levels on phosphorus (P) digestibility in ponies. None of the studies reported involved a dose response as to the effect of Ca intake on apparent P digestibility while keeping P intake constant. Thus, the influence of high dietary Ca level on apparent P digestibility was studied in balance trials by feeding six mature ponies three different Ca levels against a constant P intake. The ponies received 148, 316 and 535 mg Ca/kg BW/day with the low, intermediate and high Ca diet. Phosphorus intake was approximately 125 mg P/kg BW and magnesium (Mg) intake was approximately 35 mg Mg/kg BW/day. The intermediate and high Ca level decreased apparent digestibility, renal excretion and retention of P when compared with the low Ca level. However, apparent digestibility and renal excretion of P were not different between the intermediate and high Ca level. The high Ca level resulted in a retention of 66 mg Ca/kg BW/day. The percentage apparent digestibility of Ca was lower for the intermediate and high Ca level compared with the low Ca level. Magnesium digestibility was not affected by high dietary Ca level. In practice, high absolute amounts of Ca should be prevented especially when low amounts of P are fed; P digestibility will be depressed and a negative P balance may occur.
Bovine Viral Diarrhoea Virus is Internalized by Clathrin‐dependent Receptor‐mediated Endocytosis
Authors: Grummer B. , Grotha S. , Greiser‐Wilke I.
Published: December 2004

Bovine viral diarrhoea virus (BVDV) is a pestivirus within the family Flaviviridae. In contrast to the members of the genus flavivirus, nothing is known about the viral entry route for pestiviruses. In this study, the process of BVDV infection following attachment to the cell surface was examined. BVDV clearly co‐localizes with clathrin, with early endosome antigen‐1 (EEA‐1), an early endosome marker, and also with lysosomal‐associated membrane protein‐2 (LAMP‐2), a lysosomal marker. BVDV internalization is inhibited by compounds that block clathrin‐ but not caveolae‐dependent endocytosis. These findings demonstrate that BVDV enters the cells via the clathrin‐coated pit pathway.
Efficacy of Oral Vaccination in the Final Stage of Fox Rabies Elimination in Switzerland
Authors: Bugnon P. , Breitenmoser U. , Peterhans E. , Zanoni R.
Published: December 2004

Subsequent to rabies vaccination campaigns, two well‐established methods for the determination of the proportion of vaccinated foxes – the detection of tetracycline (TC) in bones and the detection of virus neutralizing antibodies (VNA) in thoracic fluids – were used and compared. Special emphasis was given to the effect of a new method of bait distribution at the den, which is primarily targeted at young foxes. The overall proportion of vaccinated animals estimated by TC was 60% as compared to 50% by VNA. In young foxes overall, significantly lower proportions of vaccinated animals (58% by TC and 40% by VNA) than in adult foxes (75 and 59%) were estimated with both methods. Low proportions of vaccinated young animals were found after spring (39 and 18%), but also after autumn vaccination (56 and 35%). In contrast, after den vaccination the level of vaccination of young foxes reached that of adult foxes. The theoretical implication of the successful elimination of fox rabies in Switzerland in spite of a relatively low overall proportion of VNA‐positive animals is discussed.
Significance of β2‐ToxigenicClostridium perfringensInfections in Animals and Their Predisposing Factors – A Review
Authors: Schotte U. , Truyen U. , Neubauer H.
Published: December 2004

The novelβ2‐toxin ofClostridium perfringenshas recently been described as the cause of enteric diseases in animals. The biological activity ofβ2‐toxin is similar to that of theβ1‐toxin with a possibly weaker cytotoxic activity. However, the production ofβ2‐toxinin vitrois not seen in allβ2‐toxin‐gene (cpb2)‐positiveC. perfringensstrains, and to deduce a clinical importance solely from the detection ofcpb2is difficult. Detection ofcpb2‐positiveC. perfringensfrom various animal species with and without enteric diseases demonstrates the wide distribution ofcpb2in nature, and the presence ofcpb2gene is therefore not considered a risk by itself. Predisposing factors like low trypsin activity in the intestinal tract, antibiotic and/or antiphlogistic treatment or changes in diet can result in the selection ofβ2‐toxigenicC. perfringenswhich may lead to enteritis or enterotoxaemia.
DisseminatedMycobacterium avium–intracellulareInfection in a Persian Cat
Authors: Knippel A. , Hetzel U. , Baumgärtner W.
Published: December 2004

This report describes a disseminated infection with mycobacteria of the avium/intracellulare complex in a Persian cat in the absence of cutaneous lesions. Postmortem examination revealed severe granulomatous inflammation with numerous intrahistiocytic acid‐fast bacilli in multiple organs. A gastrointestinal port of entry seems likely, as the ileocaecal lymph node was most severely affected.
A Spontaneous and Fatal Jejunal Intussusception in a European Brown Hare Associated withEimeria leporis
Authors: McCulloch C. R. , Prosl H. , Schmidt P.
Published: December 2004

A recently dead adult female European brown hare (Lepus europaeusPallas) was found in the wild with no evidence of trauma or external injury. Necropsy revealed symptoms consistent with endotoxic shock and a haemorrhagic jejuno‐jejunal intussusception with a necrotic intussusceptum. Small, unattached nodules were present extensively in the jejunal lumen and within the intussuscipiens. These nodules proved to be masses of unsporulatedEimeria leporisoocysts. Review of the literature revealsE. leporisto be a common parasite of wild hares, with protracted pathogenic potential under some circumstances. This is the first report of intussusception in this species and the most severe lesion seen associated withE. leporis. This case suggests thatE. leporismay be more harmful to the wild European brown hare population than previously supposed.
Intrapancreatic pseudoaneurysm associated with pancreatitis mimicking pancreatic tumor
Authors: HASHIMOTO MASAJI , WATANABE GORO , MATSUDA MASAMICHI , MORI MASAYA
Published: December 2004

A 48‐year‐old man, who had suffered a bout of acute pancreatitis in September 2000, was found in March 2001 to have an increased concentration of serum amylase. A tumor in the pancreas body associated with stenosis and prestenotic dilatation of the main pancreatic duct was detected using imaging techniques. Distal pancreatectomy was performed under the diagnosis of pancreatic carcinoma. An intrapancreatic hematoma due to rupture of a pseudoaneurysm of the intrapancreatic artery was found in the resected specimen. This case illustrates how difficult it is to diagnose a small cancerous tumor in the pancreas and the rare presentation of this intrapancreatic pseudoaneurysm, which developed in a patient with a recent history of acute pancreatitis.