bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of B cells in immunity against larval Strongyloides stercoralis in mice
Authors: Herbert De’broski R. , Nolan Thomas J. , Schad Gerhard A. , Abraham David
Published: March 2003

The objective of this study was to examine the role of B cells in primary and challenge infections of larval Strongyloides stercoralis in mice. Two strains of B‐cell deficient mice were used in these studies, µMT mice that lack all B cells and Xid mice that lack B‐1 cells. Primary immune responses in µMT mice were sufficient to eliminate all parasites within 1 week after infection. Immunized µMT and Xid mice, however, were unable to kill challenge parasites at 24 h post infection, the time that they were eliminated in immunized wild‐type mice. This was despite having a significant increase in interleukin‐5 secreting cells and high numbers of eosinophils in the microenvironment of the challenge larvae. In addition, immunized Xid mice did not generate parasite‐specific immunoglobulin (Ig)M but did develop a weak IgG response compared to wild‐type mice. These results demonstrate a dichotomy in the requirement of B cells in immunity to S. stercoralis. B cells are not required in the primary response, yet they are required in the secondary immune response. B‐1 cells are required for the secondary immune response and their role appears to be the production of IgM and not as a source of immunoregulatory molecules.
Transformation of two‐pyroxene hornblende granulite to garnet granulite involving simultaneous melting and fracturing of the lower crust, Fiordland, New Zealand
Authors: Daczko N. R. , Clarke G. L. , Klepeis K. A.
Published: March 2003

Granulite facies gabbroic and dioritic gneisses in the Pembroke Valley, Milford Sound, New Zealand, are cut by vertical and planar garnet reaction zones in rectilinear patterns. In gabbroic gneiss, narrow dykes of anorthositic leucosome are surrounded by fine‐grained garnet granulite that replaced the host two‐pyroxene hornblende granulite at conditions of 750 °C and 14 kbar. Major and trace element whole‐rock geochemical data indicate that recrystallization was mostly isochemical. The anorthositic veins cut contacts between gabbroic gneiss and dioritic gneiss, but change in morphology at the contacts, from the anorthositic vein surrounded by a garnet granulite reaction zone in the gabbroic gneiss, to zones with a septum of coarse‐grained garnet surrounded by anorthositic leucosome in the dioritic gneiss. The dioritic gneiss also contains isolated garnet grains enclosed by leucosome, and short planar trains of garnet grains linked by leucosome. Partial melting of the dioritic gneiss, mostly controlled by hornblende breakdown at water‐undersaturated conditions, is inferred to have generated the leucosomes. The form of the leucosomes is consistent with melt segregation and transport aided by fracture propagation; limited retrogression suggests considerable melt escape. Dyking and melt escape from the dioritic gneiss are inferred to have propagated fractures into the gabbroic gneiss. The migrating melt scavenged water from the surrounding gabbroic gneiss and induced the limited replacement by garnet granulite.
The Cooma Metamorphic Complex, a low‐P, high‐T (LPHT) regional aureole beneath the Murrumbidgee Batholith
Authors: Richards S. W. , Collins W. J.
Published: March 2003

The Cooma Complex of the Lachlan Fold Belt, south‐eastern Australia, is characterised by a large (c. 10 km wide) low‐P, high‐T metamorphic aureole surrounding a small (3 × 6 km) granite pluton. The aureole extends northward to envelop the eastern lobe of the Murrumbidgee Batholith and progressively narrows to a kilometre wide hornfelsic aureole some 50 km north of Cooma. At its northern extremity, the batholith has intruded its own volcanic cover. These regional relations suggest that the Murrumbidgee Batholith is gently tilted to the north, with the Cooma Complex representing the aureole beneath the batholith.

Two main deformation events, D3 and D5, affected the aureole. The inner, high‐grade migmatitic domain contains upright F5 folds defined by a composite, transposed S3/S0 fabric and S3/S0 concordant leucosomes. The folded stromatic migmatites define the western limb of a F5 synform, with its axis located in the batholith. Lenses and sheets of the Murrumbidgee Batholith intruded along S3 but also preserve S3 as a strong, solid‐state foliation. S3 and the granite sheets but are also folded by F5, outlining a fanning positive flower structure. These relations indicate that most of the batholith was emplaced before and during D3, but intrusion persisted until early syn‐D5.

Formation of the Cooma Granodiorite occurred post‐D3 to early syn‐D5, after formation of the wide metamorphic aureole during early syn‐D3 to early syn‐D5. The Murrumbidgee Batholith was emplaced between pre‐D3 to early syn‐D5, synchronous with the formation of the Cooma Complex. The structural and metamorphic relations indicate that the Murrumbidgee Batholith was the ultimate heat source responsible for the Cooma Metamorphic Complex.

D3 structures and metamorphic isograds are subparallel to the batholith margin for over 50 km. This concordance probably extends vertically, suggesting that the isograds also fan outward from the batholith margin. This implies an inverted metamorphic sequence focused on the Murrumbidgee Batholith, although the base has been almost completely removed by erosion in the Cooma Complex. The field evidence at Cooma, combined with previous thermal modelling results, suggest that extensive LPHT metamorphic terranes may represent regional metamorphic aureoles developed beneath high‐level granitic batholiths.
Principles and practical grouping for the use of drill and practice programs
Authors: Jackson A. , Kutnick P. , Kington A.
Published: March 2003

Abstract A previous paper showed that young children performed better when working as individuals rather than in pairs on a drill and practice program. This paper reports an analysis of behaviour and talk for individuals and single sex pairs using a computer‐based drill and practice activity to explain differences in performance. Results indicated that individuals were more likely to be task‐focused and to complete tasks successfully than children working in pairs. Differences were found in off‐task activity, behaviours and type of talk. Grouping and verbal interaction are discussed in relation to the type of task/program that children are asked to undertake, and how both task and peer presence may constrain the child's task focus and performance when reinforcing pre‐existing knowledge.
‘Bridging Tools’ for change: evaluating a collaborative learning network
Authors: Bonamy J. , Charlier B. , Saunders M.
Published: March 2003

Abstract  This paper outlines the evaluation approach associated with the Learn‐Nett project under the SOCRATES initiative. It describes the project, locates the role of evaluation within it and finally conceptualises the role evaluation might play in a change process. The paper argues that evaluation in these circumstances can be essentially formative but also be prompted by a search for new knowledge in the area of changing practices in learning. It identifies ‘transition’ as anomic and the need to develop ‘provisional stability’ for change to occur effectively. In such periods of change, evaluation products can act as useful ‘bridging tools’ which can support the development of ‘provisional stability’.
Feedback for web‐based assignments
Authors: Collis B. , De Boer W. , Slotman K.
Published: March 2003

Abstract In the Faculty of Educational Science and Technology at the University of Twente an educational concept based on the ideas of increased flexibility in learning options and the active student, has been in place since 1998. In this approach, many courses have moved from a model of lectures and a final examination or single large project, to a model of six or seven assignments or subparts of a larger overall project, each submitted via a web‐based course‐management system and each worth a certain portion of the overall course grade. Feedback has become a key aspect of teaching as well as assessment. This paper gives an overview of feedback as part of the assessment process in learning settings making use of web‐based environments. This is followed by some examples of feedback strategies supported by the web‐based system in use in the faculty and a description of a web‐based decision‐support tool, currently under development, for instructors relating to feedback.
Web‐based peer assessment: feedback for students with various thinking‐styles
Authors: Lin S.S.J. , Liu E.Z.F. , Yuan S.M.
Published: March 2003

Abstract This study used aptitude treatment interaction design to examine how feedback formats (specific vs. holistic) and executive thinking styles (high vs. low) affect web‐based peer assessment. An Internet‐based (anonymous) peer‐assessment system was developed and used by 58 computer science students who submitted assignments for peer review. The results indicated that while students with high executive thinking styles significantly improved over two rounds of peer assessment, low executive students did not improve through the cycles. In addition, high executive students contributed substantially better feedback than their low executive counterparts. In the second round of peer assessment, thinking style and feedback format interactively affected student learning. Low executive students receiving specific feedback significantly outperformed those receiving holistic feedback. In receiving holistic feedback, high executive thinkers outperformed their low executive counterparts. This study suggests that future web‐based peer assessment adopts a specific feedback format for all students.
Deferring to resources: collaborations around traditional vs computer‐based notes
Authors: Crook C.
Published: March 2003

AbstractUndergraduate students were observed engaged in a species of collaboration rarely studied and yet which is grounded in an authentic form of normal study practice: namely, revising a course in preparation for an exam. Pairs of undergraduates were convened for recorded sessions in which they did this around either their own personal lecture notes or around a set of notes authored by the lecturer and made available as web‐readable computer documents. Although the goals, motives and orientations of these pairings were similar, the nature of the collaborative resource effected the character and rhythm of the joint conversation. The computer‐based documents led to less on‐task collaborative talk. Moreover, these documents sustained conversation that was more fragmented around successive short topics. Observations are made regarding how certain discursive openings are more readily afforded when revision talk is mediated by a less singular, authorised, and directive form of document.
Understanding user perceptions of World‐wide web environments
Authors: Liaw S.‐S.
Published: March 2003

Abstract The purpose of this study was to develop and test a conceptual model of individual perceptions of Web technology as a use and training tool. The model presents a perspective of users' attitudes toward Web environments. This model integrates the Technical Acceptance Model, Social Cognitive Theory, individual attitudes, motivation and self‐efficacy perspectives to develop a new aspect of users' perceptions toward Web technology acceptance and use. The study provides some evidence that the conceptual model helps the understanding of user perceptions to Web environments. In addition, training and educational programmes on computers may foster a positive feeling towards the Web. Furthermore, the more individuals have self‐efficacy towards Web technology, the more individuals have motivation to use the Web.
Unexpected anthropophagic behaviour in Anopheles quadriannulatus
Authors: Pates H. V. , Takken W. , Curtis C. F. , Huisman P. W. , Akinpelu O. , Gill G. S.
Published: March 2003

Abstract. The strongly anthropophilic behaviour of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae), the most important malaria vector in Africa, has been demonstrated by field and laboratory studies. Other members of the An. gambiae complex express varied degrees of anthropophily. Anopheles quadriannulatus (Theobald) species A and B are more zoophilic members of the complex and hence are considered to be of no medical importance. Olfactometer experiments with An. quadriannulatus species A have demonstrated attraction to both human and cow odour. To extend these olfactometer observations a choice experiment was conducted in an outdoor cage with a human and a calf as baits, using laboratory‐reared mosquitoes. Anopheles gambiae s.s. (from Liberia) and two strains of An. quadriannulatus species A (SKUQUA from South Africa, SANGQUA from Zimbabwe), marked with different coloured fluorescent powders for identification purposes, were released simultaneously and given an equal opportunity to feed on either host. The experiment was repeated six times. Bloodmeals were identified using the precipitin technique. Anopheles gambiae s.s. showed highly anthropophagic behaviour, taking 88% of bloodmeals from the human host. In contrast, both strains of An. quadriannulatus fed with equal frequency on the human or the calf; the response to either host was not significantly different. These results confirm the olfactometer findings and demonstrate anthropophagic behaviour not previously recorded in this species. This finding has implications for prospective manipulation of host preference for genetic control purposes.
Mecoptera is paraphyletic: multiple genes and phylogeny of Mecoptera and Siphonaptera
Authors: Whiting Michael F.
Published: March 2003

Phylogenetic relationships among members of the Mecoptera and Siphonaptera were inferred from DNA sequence data. Four loci (18S and 28S ribosomal DNA, cytochrome oxidase II and elongation factor‐1α) were sequenced for 69 taxa selected to represent major flea and mecopteran lineages. Phylogenetic analyses of these data support a paraphyletic Mecoptera with two major lineages: Nannochoristidae + (Siphonaptera + Boreidae) and Meropidae + ((Choristidae + Apteropanorpidae) (Panorpidae + (Panorpidae + Bittacidae))). The flea family Ctenophthalmidae is paraphyletic, and the Ceratophylloidea is monophyletic. Morphological evidence is discussed which is congruent with the placement of Siphonaptera as sister group to Boreidae.
The neurology and neuropathology of coeliac disease
Authors: Wills A. J.
Published: March 2003

A number of neurological syndromes have been described in association with coeliac disease. These include disorders of the central nervous system encompassing epilepsy, myoclonus, ataxia, internuclear opthalmoplegia, multifocal leukoencephalopathy and dementia. Most of these associated conditions show a poor response to gluten restriction. Peripheral neuropathies, of axonal and demyelinating types, have also been reported and may respond to elimination of gluten from the diet. The mechanism underlying these processes remains obscure but may be immunological or related to trace vitamin deficiencies. Controversially, it has also been claimed that occult coeliac disease accounts for a substantial proportion of patients with neurological dysfunction of unknown cause. Some authorities recommend that cryptogenic ataxias and neuropathies should be routinely screened for the presence of gluten‐sensitivity but this remains contentious and has not been universally accepted. This review will attempt to review the clinical and pathological findings in this condition and speculate on pathogenesis and directions for future research.
Fibrous meningeal tumours with extensive non‐calcifying collagenous whorls and glial fibrillary acidic protein expression: the whorling‐sclerosing variant of meningioma
Authors: Haberler C. , Jarius C. , Lang S. , Rössler K. , Gruber A. , Hainfellner J. A. , Budka H.
Published: March 2003

Meningiomas comprise a wide range of morphological patterns. We describe unusual fibrous meningeal tumours in two patients, composed of extensive non‐calcifying collagenous whorls of varying size, resembling non‐calcified psammoma bodies, while interposed tumour cells are sparse. Immunohistochemistry showed expression of S‐100, vimentin and glial fibrillary acidic protein, whereas only single tumour cells stained for epithelial membrane antigen. Electron microscopy detected desmosomes or desmosome‐like structures in both specimens. We conclude that these tumours represent a peculiar whorling‐sclerosing variant of fibrous meningioma. Recognition of this meningioma variant is important in the differential diagnosis of meningioma versus other fibrous tumours of the meninges, including solitary fibrous tumours of the meninges, unusual forms of desmoplastic gliomas or chondroid tumours.
Diel patterns of locomotor activity in Cydia pomonella: age and sex related differences and effects of insect hormone mimics
Authors: Keil Sabine , Gu Hainan , Dorn Silvia
Published: March 2003

Abstract. The diel pattern of locomotor activity in the codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) was investigated in the laboratory, using a computer‐based infra‐red actograph. The level of locomotor activity varied with sex and age. On the day of emergence, females were more active than males, but on days 2, 4, 6 and 12 males were approximately twice as active as females. Males reached their highest activity on day 4 and females on day 12. Both sexes were most active at dusk. Their activity patterns were fitted to a set of polynomial regression models. Treatment with 400 p.p.m. of Juvenile Hormone mimic, fenoxycarb, stimulated locomotor activity and provoked a marked activity peak at dawn in both virgin and mated females. A similar treatment with the ecdysone agonist tebufenozide showed a neutral effect on the locomotor activity of females. Possible implications of these findings are discussed in relation to the physiology of the moth and to its dispersal behaviour.
Oviposition and oogenesis in virgin fire ant females Solenopsis invicta are associated with a high level of dopamine in the brain
Authors: Boulay Raphael , Hooper‐Bui Linda M. , Woodring Joseph
Published: March 2003

Abstract. In the fire ant Solenopsis invicta Buren, virgin females are capable of shedding their wings (dealation) and laying haploid eggs. However, dealation and reproduction are inhibited by a queen primer pheromone that depresses the release of Juvenile Hormone by the corpora allata. In an attempt to identify other neural signals that trigger the reproductive system, we measured the effect on brain biogenic amines of separation from the queen. Dopamine in the brain of virgin females increased from 552 ± 42 to 971 ± 65 fMol/brain when reproduction and dealation were stimulated by 15 days of separation. Octopamine and 5‐hydroxytryptamine did not change significantly after the separation. Isolated virgin females fed with a tyrosine hydroxylase inhibitor 3‐iodo‐l‐tyrosine mixed in sucrose for 15 days laid significantly fewer eggs and had fewer chorionated oocytes in their ovarioles than females fed with sucrose only. Restoring dopamine biosynthesis by adding l‐dopa to the food also restored oogenesis and oviposition. Dealation was not affected by 3‐iodo‐l‐tyrosine or l‐dopa. The possible role of dopamine as the neural target of the queen pheromone regarding its potent allotoregulatory effect in other insects is discussed.
Phylogenetic classification of Eudorylini (Diptera: Pipunculidae)
Authors: Skevington Jeffrey H. , Yeates David K.
Published: March 2003

Abstract. The phylogenetic relationships of members of Eudorylini (Diptera: Pipunculidae: Pipunculinae) were explored. Two hundred and fifty‐seven species of Eudorylini from all biogeographical regions and all known genera were examined. Sixty species were included in an exemplar‐based phylogeny for the tribe. Two new genera are described, Clistoabdominalis and Dasydorylas. The identity of Eudorylas Aczél, the type genus for Eudorylini, has been obscure since its inception. The genus is re‐diagnosed and a proposal to stabilize the genus and tribal names is discussed. An illustrated key to the genera of Pipunculidae is presented and all Eudorylini genera are diagnosed. Numerous new generic synonyms are proposed. Moriparia nigripennis Kozánek & Kwon is preoccupied by Congomyia nigripennis Hardy when both are transferred to Claraeola, so Cla. koreana Skevington is proposed as a new name for Mo. nigripennis.
Midlife and Older Rural Women's Adherence to U.S. Dietary Guidelines Across Stages of Change in Healthy Eating
Authors: Pullen Carol , Noble Walker Susan
Published: March 2003

Poor diet is one of the factors that influences morbidity and premature mortality among older women. The purpose of this descriptive correlational study was to assess (a) healthy eating behaviors of midlife and older rural women, as reflected by adherence to the Dietary Guidelines for Americans, and (b) differences in daily servings in each food group consumed by the women across stages of readiness for change in healthy eating. A sample of 371 midlife and older rural women attending a national meeting of a community education organization completed a questionnaire, including items to measure healthy eating and readiness for change in healthy eating. Only 5.9% of the women adhered to all levels of the Food Pyramid. Adherence to individual levels ranged from 3.5% for grain products to 65.4% for fruit. Analyses of variance revealed significant differences (p < 0.05) in servings consumed daily across stages of change for grain (F=4.80), fruits (F=19.02), vegetables (F=9.24), dairy (F=2.45), and meats (F=1.98). Findings suggest the need for community health nurses to design dietary interventions tailored for women's stage of readiness for change to reduce disability in this vulnerable population.
Th1/Th2 cytokine profiles in saliva of HIV‐positive smokers with oropharyngeal candidiasis
Authors: Slavinsky J. , Myers T. , Swoboda R. K. , Leigh J. E. , Hager S. , Fidel P. L.
Published: March 2003

Oropharyngeal candidiasis (OPC) is a common opportunistic infection among HIV‐positive individuals and often correlates with a CD4 cell number < 200 cells/µl. This study further examined the association of smoking and OPC in HIV‐positive persons. A strong association between smoking and OPC was seen in HIV‐positive individuals with ≥ 200 CD4 cells/µl. In HIV‐positive persons with ≥ 200 CD4 cells/µl, OPC+ smokers had lower gamma‐interferon (IFN‐γ) concentrations and a trend toward higher interleukin (IL)‐4 concentrations in whole saliva compared to OPC– persons with ≥ 200 CD4 cells/µl, a cytokine profile consistent with that observed in HIV+OPC+ persons with < 200 CD4 cells/µl. These results suggest that premature OPC in HIV‐positive smokers is associated with altered oral host defence mechanisms that cannot be overcome by levels of systemic CD4 cells that are otherwise sufficient to protect against OPC.
Identification of Candida dubliniensis among oral yeast isolates from an Italian population of human immunodeficiency virus‐infected (HIV+) subjects
Authors: Giammanco G. M. , Pizzo G. , Pecorella S. , Distefano S. , Pecoraro V. , Milici M. E.
Published: March 2003

Candida dubliniensis, an emerging oral pathogen, phenotypically resembles Candida albicans so closely that it is easily misidentified as such. The aim of the present study was to evaluate the usefulness of two phenotypic methods, growth at 45°C and 2,3,5‐triphenyltetrazolium chloride (TTC) reduction, for confirming presumptive identification of C. dubliniensis and C. albicans by colony color on CHROMagar Candida (CAC) medium. A combination of these methods was used to establish the prevalence of oral C. dubliniensis in an Italian population of 45 human immunodeficiency virus (HIV)‐infected subjects. Twenty‐two samples (48.9%) were positive for yeasts on CAC medium producing a total of 37 fungal isolates. The colony color and 45°C growth ability test correctly identified all C. dubliniensis and C. albicans isolates (5/37, 13.5%, and 16/37, 43.2%, respectively), while assessment of TTC reduction misidentified one C. albicans isolate. The isolation rate of C. dubliniensis was 11.1% (5/45 patients). All of the C. dubliniensis isolates were highly susceptible to fluconazole (MIC = 0.5 µg/ml). The combination of CAC medium screening with growth at 45°C and TTC reduction tests may represent a simple, reliable and inexpensive identification protocol for C. dubliniensis.
Multiple myeloma with skin involvement
Authors: Güvenç B , Canataroǧlu A , Gümürdülü Y , Gümürdülü D , Paydaş S
Published: March 2003

Multiple myeloma (MM) is a plasma cell dyscrasia seen in the elderly that constitutes 10% of all haematopoietic neoplasias. It is a systemic disorder affecting various organs, in particular the kidneys and bones. Skin involvement is not a common finding. This report presents a case of MM with skin involvement.
Adverse reactions to FMD vaccine
Authors: Yeruham Israel , Yadin Hagy , Haymovich Moshe , Perl Shmuel
Published: March 2003

A case of adverse post‐vaccination allergic reactions, which occurred in a dairy cattle herd 8 days after the annual foot‐and‐mouth disease (FMD) vaccination, is described. The dermatologic lesions observed in these cattle included: urticaria, exudative and necrotic dermatitis, along with oedema and vesicles on the teats. These reactions occurred in 11.3% of the heifers, in 10% of the first‐lactating cows and in 14.6% of the adult cows. The average loss of milk production for an affected cow on this farm was 21.5% per day, for seven consecutive days. The extent of the lesions was apparently related to concurrent diseases such as bovine virus diarrhea – mucosal disease complex (BVD–MD) and Johne’s disease and, to a lesser degree, correlated with the age or breed.
Zonal dermal separation: a distinctive histopathological lesion associated with hyperelastosis cutis in a Quarter Horse
Authors: Brounts Sabrina H. , Rashmir‐Raven Ann M. , Black Sharon S.
Published: March 2003

This case report describes a distinctive deep cutaneous lesion in a 1‐year‐old Quarter Horse filly with hyperelastosis cutis. The horse had a typical clinical presentation of hyperelastic skin associated with a 6‐month history of cutaneous wounds that developed following minor cutaneous trauma. Punch biopsies of skin from the affected horse were thinner than similar biopsies from an age‐ and breed‐matched control. Significant microscopic lesions were not seen in cutaneous punch biopsies stained with haematoxylin and eosin and Masson’s trichrome stains, but the ultrastructure of the dermis from the affected horse was characterized by variation in collagen fibre diameter and loose packing of collagen fibres within bundles. The horse was euthanized and necropsied, and full‐thickness sections of skin were collected and examined microscopically. Affected skin was of normal thickness; however, the deep dermis contained a distinctive horizontal linear zone in which separation of collagen bundles resulted in the formation of large empty cleft‐like spaces between the upper and lower regions of the deep dermis. We suggest the term ‘zonal dermal separation’ for this microscopic lesion. Incisional full‐thickness skin biopsies should be taken in suspected cases of equine hyperelastosis cutis because punch biopsies may not obtain enough deep dermis to adequately represent pathological change in the skin of horses with this disorder.
Skin mast cell histamine release following stem cell factor and high‐affinity immunoglobulin E receptor cross‐linking in dogs with atopic dermatitis
Authors: Hammerberg Bruce , Olivry Thierry , Orton Susan M.
Published: March 2003

Stem cell factor (SCF) influences mast cell activation and inflammatory mediator release, and is elevated in tissues undergoing allergic inflammation. Wheal formation in response to the injection of SCF or anti‐immunoglobulin (Ig)E antibody injection was compared between normal (n = 10) and nonlesional atopic (n = 10) canine skin. In situ SCF secretion was compared between lesional and nonlesional skin using immunohistochemistry. Histamine release by skin cell suspensions after stimulation with SCF, concanavalin A (ConA) or rabbit anticanine IgE antibodies was compared between normal and atopic dogs. All dogs exhibited strong responses to intradermal SCF injection at 10 and 50 ng mL−1. Atopic dogs had significantly (P = 0.002) larger wheal responses to anti‐IgE than normal dogs; but there was no difference in numbers of skin mast cells bearing IgE as detected by immunohistochemistry. Only atopic dogs exhibited interstitial deposition of SCF in both lesional and nonlesional skin specimens. Median histamine release stimulated by SCF in the absence of IgE from lesional skin cells was higher in atopic than normal dogs (P = 0.04). These experiments suggest that dermal SCF secretion could potentiate histamine release following IgE receptor cross‐linking and thus, could be one of the explanations for the inherent mast cell hyperexcitability observed in canine atopic dermatitis.
Lateral root formation is blocked by a gain‐of‐function mutation in the SOLITARY‐ROOT/IAA14 gene of Arabidopsis
Authors: Fukaki Hidehiro , Tameda Satoshi , Masuda Haruka , Tasaka Masao
Published: March 2003

Lateral root development is a post‐embryonic organogenesis event that gives rise to most of the underground parts of higher plants. Auxin promotes lateral root formation, but the molecular mechanisms involved are still unknown. We have isolated a novel Arabidopsis mutant, solitary‐root (slr), which has reduced sensitivity to auxin. This dominant slr‐1 mutant completely lacks lateral roots, and this phenotype cannot be rescued by the application of exogenous auxin. Analysis with cell‐cycle and cell‐differentiation markers revealed that the slr‐1 mutation blocks cell divisions of pericycle cells in lateral root initiation. The slr‐1 mutant is also defective in root hair formation and in the gravitropic responses of its roots and hypocotyls. Map‐based positional cloning and isolation of an intragenic suppressor mutant revealed that SLR encodes IAA14, a member of the Aux/IAA protein family. Green fluorescent protein‐tagged mutant IAA14 protein was localized in the nucleus, and the gain‐of‐function slr‐1/iaa14 mutation decreased auxin‐inducible BA‐GUS gene expression in the root, suggesting that SLR/IAA14 acts as a transcriptional repressor. These observations indicate that SLR/IAA14 is a key regulator in auxin‐regulated growth and development, particularly in lateral root formation.
H2O2 plays different roles in determining penetration failure in three diverse plant–fungal interactions
Authors: Mellersh Denny G. , Foulds Inge V. , Higgins Verna J. , Heath Michele C.
Published: March 2003

Fungal plant pathogens that attempt to penetrate and feed on living cells frequently trigger a localized plant defence response that results in fungal penetration failure. In the current study we demonstrate that breakdown products of the cell wall released by the localized application of hemicellulase elicit localized responses including, sequentially, extracellular H2O2 generation; accumulation of phenolic compounds; and cross‐linking of proteins in the cell wall. In a detailed time‐course study of three plant–fungus interactions that result in a high frequency of penetration failure, only one plant–fungus combination displayed a similar profile of responses to that induced by localized cell‐wall degradation. The additional generation of extracellular O2– in one interaction, and the absence of phenolic compounds in the cell wall in another, demonstrate that plant responses to the penetration process may be influenced by activities of the penetrating fungus. Significantly, H2O2 generation was the only response detected in all three plant–fungal combinations at the correct time and place to account for penetration failure, and in all three combinations the enzymatic removal of H2O2 resulted in increased penetration success. Pharmacological studies suggest that in two of the three interactions, H2O2 generation required cytoskeletal involvement but was independent of transcription or translation, although inhibition of the latter processes increased fungal penetration. In at least one of these two interactions, the data suggest that H2O2 generation and new gene expression act within the same penetration‐inhibiting pathway, possibly through the involvement of phenolic materials. However, enzymatic removal of H2O2 from the third interaction almost completely eliminated penetration failure, while interference with cytoplasmic processes had no effect, suggesting that H2O2 generation in this system did not require protoplast involvement and, alone, was necessary and sufficient to account for fungal penetration failure.
Fusion genetic analysis of jasmonate‐signalling mutants in Arabidopsis
Authors: Jensen Anders B. , Raventos Dora , Mundy John
Published: March 2003

Jasmonates induce plant‐defence responses and act to regulate defence‐related genes including positive feedback of the lipoxygenase 2 (LOX2) gene involved in jasmonate synthesis. To identify jasmonate‐signalling mutants, we used a fusion genetic strategy in which the firefly luciferase (FLUC) and Escherichia coliβ‐glucuronidase (GUS) reporters were expressed under control of the jasmonate‐responsive LOX2 promoter. Spatial and temporal patterns of reporter expression were determined initially, and revealed that JA‐responsive expression from the LOX2 promoter required de novo protein synthesis. Reporter activity was also induced by the protein kinase inhibitor staurosporine and antagonized by the protein phosphatase inhibitor okadaic acid. FLUC bio‐imaging, RNA gel‐blot analysis and progeny analyses identified three recessive mutants that underexpress the FLUC reporter, designated jue1, 2 and 3, as well as two recessive mutants, designated joe1 and 2, that overexpress the reporter. Genetic analysis indicated that reporter overexpression in the joe mutants requires COI. joe1 responded to MeJA with increased anthocyanin accumulation, while joe2 responded with decreased root growth inhibition. In addition, reporter induction and endogenous LOX2 expression by staurosporine was absent in joe2.
Retracted: Identification, subcellular localization and some properties of a cysteine‐rich suppressor of gene silencing encoded by peanut clump virus
Authors: Dunoyer Patrice , Pfeffer Sébastien , Fritsch Christiane , Hemmer Odile , Voinnet Olivier , Richards K. E.
Published: March 2003

In plants, post‐transcriptional gene silencing (PTGS) is part of a defence mechanism against virus infection. Several plant viruses have been shown to encode proteins which can counteract PTGS. In this paper it is demonstrated that P15 of peanut clump pecluvirus (PCV) has anti‐PTGS activity. P15 is a small cysteine‐rich protein with no sequence similarity to previously described PTGS‐suppressor proteins which has several novel properties. It possesses four C‐terminal proximal heptad repeats that can potentially mediate a coiled‐coil interaction and is targeted to peroxisomes via a C‐terminal SKL motif. The coiled‐coil sequence is necessary for the anti‐PTGS activity of P15, but the peroxisomal localization signal is not, although it is required for efficient intercellular movement of the virus.
Salt causes ion disequilibrium‐induced programmed cell death in yeast and plants
Authors: Huh Gyung‐Hye , Damsz Barbara , Matsumoto Tracie K. , Reddy Muppala P. , Rus Ana M. , Ibeas José I. , Narasimhan Meena L. , Bressan Ray A. , Hasegawa Paul M.
Published: March 2003

Programmed cell death (PCD) is a fundamental cellular process conserved in metazoans, plants and yeast. Evidence is presented that salt induces PCD in yeast and plants because of an ionic, rather than osmotic, etiology. In yeast, NaCl inhibited growth and caused a time‐dependent reduction in viability that was preceded by DNA fragmentation. NaCl also induced the cytological hallmarks of lysigenous‐type PCD, including nuclear fragmentation, vacuolation and lysis. The human anti‐apoptotic protein Bcl‐2 increased salt tolerance of wild‐type yeast strain and calcineurin‐deficient yeast mutant (cnb1Δ) that is defective for ion homeostasis, but had no effect on the NaCl or sorbitol sensitivity of the osmotic hypersensitive hog1Δ mutant – results that further link PCD in the response to the ion disequilibrium under salt stress. Bcl‐2 suppression of cnb1Δ salt sensitivity was ENA1 (P‐type ATPase gene)‐dependent, due in part to transcriptional activation. Salt‐induced PCD (TUNEL staining and DNA laddering) in primary roots of both Arabidopsis thaliana wild type (Col‐1 gl1) and sos1 (salt overly sensitive) mutant seedlings correlated positively with treatment lethality. Wild‐type plants survived salt stress levels that were lethal to sos1 plants because secondary roots were produced from the shoot/root transition zone. PCD‐mediated elimination of the primary root in response to salt shock appears to be an adaptive mechanism that facilitates the production of roots more able to cope with a saline environment. Both salt‐sensitive mutants of yeast (cnb1Δ) and Arabidopsis (sos1) exhibit substantially more profound PCD symptoms, indicating that salt‐induced PCD is mediated by ion disequilibrium.
Outcome of fetal talipes following in utero sonographic diagnosis
Authors: Carroll S. G. M. , Lockyer H. , Andrews H. , Abdel‐Fattah S. , McMillan D. , Kyle P. M. , Soothill P. W.
Published: March 2003

Objectives

To examine the association between fetal talipes and other defects, and outcome in relation to postnatal surgery.

Methods

All cases of talipes presenting to the fetal medicine unit between 1993 and 1998 and cases of isolated talipes presenting to the ultrasound department between 1991 and 1998 were examined. The infants were followed‐up to determine the number of cases that had structural or positional talipes and the number of cases requiring surgery.

Results

There were 76 cases, 59 of which attended the fetal medicine unit and 17 the ultrasound department. Postnatal follow‐up details were available in 31 of the 40 live births. There were three neonates with unilateral talipes at birth who were thought to have bilateral talipes on prenatal ultrasound and one neonate had bilateral talipes at birth who had been thought to have unilateral talipes prenatally. In two (6.4%) neonates in whom talipes was not confirmed at birth the abnormality was diagnosed prenatally. Of the 29 neonates with confirmed talipes at birth, the defect was structural in 26 (90%) cases and positional in three. Surgery was necessary in 21 (72%) of the 29 cases and 18 (86%) of those undergoing surgery required only one operation. When live births with associated anomalies were excluded, there were 24 cases with confirmed isolated talipes and 18 (75%) required surgery.

Conclusions

This study provides long‐term outcome data which can be used to complement current prenatal counseling and shows that in cases of fetal talipes diagnosed prenatally, 90% have a structural rather than a positional deformity. For isolated talipes three quarters of children will require surgery and in the majority of cases only one operation on the foot is necessary. Parents should be made aware of the small possibility of a false‐positive diagnosis and discrepancy between the ultrasound and postnatal diagnoses of laterality. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
A prospective longitudinal study of growth velocity in twin pregnancy
Authors: Smith A. P. M. , Ong S. , Smith N. C. S. , Campbell D.
Published: March 2003

Objectives

Fundamental research into the growth of twins is lacking. Twin growth in utero is commonly assumed to follow similar patterns of growth as that of singletons. This preliminary descriptive study on twin pregnancy aimed to define growth velocity as gestation advances, and to study if twin order, fetal sex, zygosity and chorionicity have any relationship to growth velocity.

Methods

One hundred and sixty‐two women with twin pregnancies had an ultrasound examination at fortnightly intervals from 16 weeks until delivery. Fetal measurements of biparietal diameter, abdominal circumference and femur length were performed at each examination. Growth velocity for each parameter was defined as the difference in measurements for that parameter divided by the time interval between measurements. Postnatally, zygosity and chorionicity were determined by genetic fingerprinting and inspection of the placenta, respectively.

Results

Growth velocity for all parameters decreased as gest‐ation advanced, with the downward trend more noticeable after 32 weeks. Maximum and minimum growth occurred at 22–23 weeks and 36–37 weeks, respectively. Maximum and minimum growth velocities for the abdominal circumference were 1.7 and 0.8 cm/week, respectively. Birth order, fetal sex, chorionicity and zygosity were not related to growth velocity.

Conclusions

These preliminary results suggest that growth velocity in twins decreases after 32 weeks' gestation. It appears that growth velocity is independent of birth order, fetal sex, chorionicity and zygosity. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
A comparison of sonographic cervical parameters in predicting spontaneous preterm birth in high‐risk singleton gestations
Authors: Guzman E. R. , Walters C. , Ananth C. V. , O'Reilly‐Green C. , Benito C. W. , Palermo A. , Vintzileos A. M.
Published: March 2003

Objectives

To assess the role of cervical sonography and to compare various sonographic cervical parameters in their ability to predict spontaneous preterm birth in high‐risk singleton gestations.

Design

A prospective cohort of 469 high‐risk gestations were longitudinally evaluated between 15 and 24 weeks' gestation on 1265 occasions with transvaginal cervical sonography and transfundal pressure. The cervical parameters obtained were funnel width and length, cervical length, percent funneling and cervical index. The information obtained was used for patient management. Restriction of physical activities was initiated at cervical lengths of ≤ 2.5 cm with cerclage as an option for cervical lengths of ≤ 2.0 cm.

Results

Receiver operating characteristic curve analyses showed that a cervical length of ≤ 2.5 cm between 15 and 24 weeks' gestation was equal to the other sonographic cervical parameters in its ability to predict spontaneous preterm birth. The sensitivities for delivery at < 28, < 30, < 32 and < 34 weeks' gestation were 94%, 91%, 83% and 76%, respectively, while the negative predictive values were 99%, 99%, 98% and 96%, respectively. The placement of a cerclage did not influence the positive and negative predictive values. In comparison to women with other risk factors, cervical length was best in the prediction of preterm birth in women with a prior mid‐trimester loss; an optimal cut‐off of ≤ 1.5 cm had sensitivities for delivery at < 28, < 30, < 32 and < 34 weeks' gestation of 100%, 100% 92% and 81%, respectively. The rate of preterm delivery at < 34 weeks' gestation increased dramatically when the cervical length was ≤ 1.5 cm. Cervical length was the only independent variable that entered the logistic regression model for the prediction of preterm delivery at < 34 weeks' gestation.

Conclusions

In high‐risk singleton gestations a cervical length of ≤ 2.5 cm was equal to other sonographic cervical parameters in its ability to predict spontaneous preterm birth and was better for the prediction of earlier forms of prematurity (at < 28 and < 30 weeks) than later forms (at < 32 and < 34 weeks). The optimal cervical lengths and their performance for predicting prematurity may be influenced by obstetric risk factors. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Maternal left ventricular mass and diastolic function during pregnancy
Authors: Kametas N. A. , McAuliffe F. , Hancock J. , Chambers J. , Nicolaides K. H.
Published: March 2003

Objective

To evaluate changes in left ventricular mass and diastolic function during normal pregnancy.

Methods

This was a cross‐sectional study of 125 pregnant women at 9–42 weeks of gestation and 19 non‐pregnant female controls. Two‐dimensional and M‐mode echocardiography of the maternal left ventricle and left atrium was performed.

Results

During pregnancy left ventricular mass increased by 52%. There was an increase in left ventricular end‐diastolic and end‐systolic diameters (12% and 20%, respectively), left ventricular posterior wall diameter during diastole and systole (22% and 13%, respectively) and left intraventricular septum during diastole and systole (15% and 19%, respectively). Mitral valve A‐wave maximum velocity increased during pregnancy by 19%, while mitral valve E‐wave maximum velocity and the ratio of E‐wave/A‐wave velocities increased early in pregnancy by about 14% and 6%, respectively, with a subsequent decline to 4% and 10%, respectively, below non‐pregnant levels.

Conclusion

Left ventricular mass increases during pregnancy, while left ventricular diastolic function, as demonstrated by the changes in mitral valve flow velocities, increases in the first two trimesters but declines in the third trimester. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Uterine artery Doppler and placental volume in the first trimester in the prediction of pregnancy complications
Authors: Schuchter K. , Metzenbauer M. , Hafner E. , Philipp K.
Published: March 2003

Objective

To evaluate placental volume and uterine artery Doppler in the first trimester in the prediction of pregnancies that subsequently develop pre‐eclampsia, pregnancy‐induced hypertension, preterm placental abruption or fetal growth restriction.

Methods

In 380 singleton pregnancies attending our center for nuchal translucency screening at 11–14 weeks of gestation, Doppler assessment of both uterine arteries was carried out for measurement of the pulsatility index and the mean pulsatility index of the two vessels was calculated. In addition, three‐dimensional ultrasound was used to obtain images for subsequent measurement of placental volume. The 90th centile of the uterine artery mean pulsatility index and the 10th centile of the placental volume for crown–rump length (placental quotient) were calculated. These cut‐offs were used for the prediction of pregnancy complications.

Results

Complications occurred in 36 (9.5%) of the 380 pregnancies, including 31 cases of fetal growth restriction, two of pregnancy‐induced hypertension and abruption, two of pregnancy‐induced hypertension, and one of abruption. The uterine artery mean pulsatility index was ≥ 90th centile in 38 (10%) pregnancies and this group contained nine (25%) of those that developed complications. The placental quotient was ≤ 10th centile in 39 (10%) pregnancies and this group contained eight (22%) of those that developed complications. In eight (2%) pregnancies the uterine artery mean pulsatiltiy index was ≥ 90th centile and the placental quotient was ≤ 10th centile and this group contained six (17%) of those that developed complications.

Conclusion

The combination of placental volume measurement and uterine artery Doppler in the first trimester may identify women at risk for subsequent development of pregnancy complications.Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology