bluuebunny/crossref_metadata_2025 huggingface dataset:
Brain Structures Mediating the Suckling Stimulus‐Induced Release of Prolactin
Authors: Bodnár I. , Bánky Z. S. , Tóth B. E. , Nagy G. M. , Halász B.
Published: March 2003

Suckling‐induced prolactin release is a widely studied neuroendocrine reflex, comprising a neural afferent and a humoral efferent component. The information on the brain structures involved in this reflex is fairly limited. The present studies focused on this question. The following hypothalamic interventions were made in lactating rats and the dams were tested for the suckling‐induced prolactin response: (i) unilateral or (ii) bilateral frontal cuts at the level of the anterior and posterior hypothalamus; (iii) administration of 5,7‐dihydroxytryptamine or (iv) 6‐hydroxydopamine into the hypothalamic paraventricular nucleus (PVN) to destroy serotonergic and catecholaminergic innervation of the cell group, respectively; (v) lesion of the medial subdivision of the PVN; and (vi) horizontal knife cuts below the PVN. Bilateral posterior and bilateral or unilateral anterior frontal cuts caused blockade of the suckling‐induced release of prolactin. Likewise, most dams receiving 5,7‐dihydroxytryptamine in the PVN did not respond to the suckling stimulus. Immunocytochemistry revealed that, in those rats which did not show a rise in plasma prolactin, there were almost no serotonergic fibres and terminals in the PVN, while in dams which exhibited a response, numerous serotonergic elements were evident. 6‐Hydroxydopamine treatment did not cause significant alteration in the prolactin response. Lesion of the medial, largely parvocellular subdivision of the PVN, or horizontal knife cuts below this cell group, blocked the hormone response. The findings demonstrate for the first time that: (i) interruption of the connections between the brain stem and the hypothalamus interferes with the prolactin response to the suckling stimulus; (ii) serotonergic fibres terminating in the hypothalamic PVN are involved in the mediation of the suckling stimulus; and (iii) within the PVN, neurones in the medial, largely parvocellular subdivision of the cell group take part in the transfer of the neural signal, eventually inducing prolactin release.
Regression of an acral lentiginous melanoma with an immunotherapy using a Mycobacterium tuberculosis‐extracted polysaccharide complex (Tubercin)
Authors: Chung Tai Ho , Jun Jae Bok , Jang Jae Won , Chung Hai Lee
Published: March 2003

A 77‐year‐old‐female presented with a painless, pigmented lesion, which had been present for approximately 10 years but had increased significantly in size during the last 3 months. Her past history was unremarkable, but she had been a farmer for more than 50 years and was routinely exposed to excessive amounts of sunlight. On examination, a lesion measuring 11 × 15 mm was noted on the base of left thumb. The lesion was black, slightly elevated and irregularly shaped with a relatively demarcated border. Histological examination of the biopsy specimen was consistent with an acral lentiginous melanoma (ALM) with a thickness of 4 mm. Whole body computed tomographic examination and bone scan demonstrated no distant metastases.

The patient refused not only the surgical treatment but also the recommended chemotherapeutic regimen due to her advanced age. She was then referred to the WHO Collaboration Viral Hepatitis Center at Kyungpook National University for consideration for immunotherapy with Tubercin.

The patient consented to a trial of Tubercin, which was initiated on December 24, 1999. She received three 0.3 mL subcutaneous intralesional injections of Tubercin and 2 mL intramuscular injections on the buttock every other day. After 10 months of treatment the lesion appeared as a faint brown‐colored macule and almost complete regression was noted. The follow‐up histological examination performed after 1 year showed no evidence of melanoma (Fig. 1). The treatment regimen was reduced to biweekly treatments consisting of two 0.2 mL intralesional injections and one 2 mL intramuscular injection. After an additional year, the treatment will be further reduced to a biweekly 1 mL intramuscular injection. The patient has remained free of any metastases and demonstrated no local or systemic reactions.
Tomato and barley contain duplicated copies of cryptochrome 1
Authors: Perrotta G. , Yahoubyan G. , Nebuloso E. , Renzi L. , Giuliano G.
Published: March 2003

The cryptochrome family of blue‐light photoreceptors is involved in the control of plant photomorphogenesis and photoperiodic responses. Two cryptochromes have been described in Arabidopsis and tomato. To investigate the composition of the cryptochrome gene family in angiosperms, we used a ‘garden PCR’ approach, amplifying DNA from different plant species with the same pair of degenerated oligonucleotides representing conserved sequences from the flavin‐binding domain. Different numbers of Cry‐homologous sequences were found in different species: two each in Arabidopsis (Dicots, Brassicaceae), melon (Dicots, Cucurbitaceae) and banana tree (Monocots, Musaceae); three each in tomato (Dicots, Solanaceae) and barley (Monocots, Graminaceae). These sequences contain open reading frames (OFRs) with high homology to cryptochromes, but not photolyases, and are transcribed into RNA. In each case, a Cry1‐ and a Cry2‐like sequence was recognizable. The third gene of tomato and barley seems to have arisen from recent, independent duplications of Cry1, and was thus named Cry1b. The tomato Cry1b gene encodes a protein of 583 amino acids (the shortest of the three tomato cryptochromes), with a high similarity to Cry1. The C‐terminus of Cry1b is truncated before the conserved Ser‐Thr‐Ala‐Glu‐Ser‐Ser‐Ser (STAESSS) motif found in both Cry1a and Cry2. The Cry1b mRNA is expressed throughout the tomato plant, reaching maximal levels of expression in the flower (like Cry1a and Cry2). We conclude that tomato and barley contain at least one additional expressed member of the Cry1 gene family.
Differentiation of human alloreactive CD8+ T cells in vitro
Authors: Rentenaar Rob J. , Vosters Jelle L. G. , Van Diepen Frank N. J. , Remmerswaal Ester B. M. , Van Lier René A. W. , Ten Berge Ineke J. M.
Published: March 2003

Expansion and differentiation of alloantigen‐reactive CD8+ T cells in mixed lymphocyte cultures was followed by measurement of the loss of carboxyfluorescein diacetate succinimidyl ester (CFSE) fluorescence of responder cells. Proliferation of CD8+ T cells became detectable on day 4 of culture and, 2 days later, > 60% of the CD8+ T cells in culture were dividing alloreactive lymphocytes. In parallel with expansion, CD8+ T‐cell differentiation was initiated, as evidenced by an increase in the number of CD45RA− and CD27− T cells and acquisition of the ability to produce interferon‐γ after restimulation with the specific alloantigen. Finally, although short‐term stimulation and measurement of intracellular cytokine production allowed visualization of alloreactive CD8+ T cells expanded in vitro, this procedure did not detect circulating alloreactive CD8+ T cells activated in vivo in recipients of allogeneic kidney grafts.
Mycobacterial infection inhibits established allergic inflammatory responses via alteration of cytokine production and vascular cell adhesion molecule‐1 expression
Authors: Yang Xi , Fan Yijun , Wang Shuhe , Han Xiaobing , Yang Jie , Bilenki Laura , Chen Lijun
Published: March 2003

Our previous studies, as well as those of others, have demonstrated that local or systemic Mycobacterium bovis bacille Calmette–Gue´rin (BCG) infection can inhibit de novo allergen‐induced asthma‐like reactions, but the effect of this infection on established allergic responses is unknown. The aim of this study was therefore to examine the effect of mycobacterial infection on established allergy in a murine model of asthma‐like reaction. Mice were sensitized with ovalbumin (OVA) in alum followed by infection with BCG and subsequent intranasal challenge with the same allergen. In some experiments, mice were sensitized with OVA followed by intranasal challenge with OVA and then given BCG infection with subsequent rechallenge with OVA. Mice without BCG infection but treated with OVA in the same manner, were used as a control. The mice were examined for immunoglobulin E (IgE) response and eosinophilic inflammation, mucus production, cytokine/chemokine patterns and adhesion molecule expression in the lung. The results showed that postallergen BCG infection suppressed the established airway eosinophilia and mucus overproduction, but not IgE responses. The inhibition of asthma‐like reactions by BCG infection was correlated with a shift of allergen‐driven cytokine production pattern and, more interestingly, with a dramatic decrease of vascular cell adhesion molecule‐1 (VCAM‐1) expression in the lung. These findings suggest that intracellular bacterial infection can inhibit established allergic responses via alteration of local cytokine production and the expression of adhesion molecules.
The ramification and connections of retinal fibres in layer 7 of the domestic chick optic tectum: a Golgi impregnation, anterograde tracer and GABA‐immunogold study
Authors: Sebestény T. , Davies D. C. , Zayats N. , Németh A. , Tömböl T.
Published: March 2003

Layer 7 is one of the retinorecipient layers of the avian optic tectum. However, little information is available about the neuronal organization of this layer and its implications for visual function. Golgi impregnation was used to investigate the retinal input to and the neuronal architecture of layer 7 of the chick optic tectum, which forms a narrow band between the two cell‐dense layers 6 and 8. Anterograde tracers were also used to investigate the afferent and efferent connections of layer 7, in both the light and the electron microscope, together with GABA immunogold labelling. Three types of radial neuron were defined according to the origin and course of their axons. The perikarya of these neurons were situated in tectal layers 10–11. The principal dendrites of these radial neurons ascended to the tectal surface and gave rise to dendritic side‐branches in layer 7. These dendritic side‐branches received asymmetric synapses from the terminations of retinal fibre arborisations. Type 2 radial neurons, whose axons arose from the deep pole of the perikaryon or occasionally from a basal dendrite, were shown to project to the nucleus isthmi pars magnocellularis, which has previously been demonstrated to be GABAergic and to project to glomerulus‐like complexes in tectal layers 4–5. In these layers, the dendritic branches of layer 13 neurons that project to the nucleus rotundus have previously been shown to receive retinal fibre input. Therefore, the retinal input to layer 7 may be able to modulate the transmission of information to the visual thalamus, by way of a feedback loop to layers 4–5 of the tectum involving the nucleus isthmi pars magnocellularis.
Study of the three‐dimensional geometry of the central conducting airways in man using computed tomographic (CT) images
Authors: Sauret V. , Halson P. M. , Brown I. W. , Fleming J. S. , Bailey A. G.
Published: March 2003

Clinical research on the deposition of inhaled substances (e.g. inhaled medications, airborne contaminants, fumes) in the lungs necessitates anatomical models of the airways. Current conducting airway models lack three‐dimensional (3D) reality as little information is available in the literature on the distribution of the airways in space. This is a limitation to the assessment or predictions of the particle deposition in relation to the subject’s anatomy. Detailed information on the full topology and morphology of the airways is thus required to model the airway tree realistically. This paper presents the length, diameter, gravity, coronal and sagittal angles that together describe completely the airways in 3D space. The angle at which the airways branch out from their parent (branching angle) and the rotation angle between successive bifurcation planes are also included. These data are from the study of two sets of airways computed tomography (CT) images. One CT scan was performed on a human tracheobronchial tree cast and the other on a healthy male volunteer. The airways in the first nine generations of the cast and in the first six conducting generations of the volunteer were measured using a computer‐based algorithm. The data contribute to the knowledge of the lung anatomy. In particular, the spatial structure of the airways is shown to be strongly defined by the central airways with clear angular lobar patterns. Such patterns tend to disappear with a mean gravity, coronal and sagittal angles of 90° in each generation higher than 13–15. The mean branching angle per generation appears independent of the lobe to which the airways belong. Non‐planar geometry at bifurcation is observed with the mean (± SD) bifurcation plane rotation angle of 79 ± 41° (n = 229). This angle appears constant over the generations studied. The data are useful for improving the 3D realism of the conducting airway structure modelling as well as for studying aerosol deposition, flow and biological significance of non‐planar airway trees using analytical and computational flow dynamics modelling.
Shoot damage effects on regeneration of maples (Acer) across an understorey‐gap microenvironmental gradient
Authors: Sipe T. W. , Bazzaz F. A.
Published: March 2003

We measured whole‐plant survival, frequency of leader (mainstem terminal bud) damage among survivors and growth responses of intact and damaged juveniles of three Acer species over 3 years along a microenvironmental gradient represented by the understorey and two sizes of artificially created canopy gaps in central Massachusetts, United States of America.

For all species combined, survival decreased while the frequency of leader damage among survivors increased across the gradient of microsite exposure. Acer rubrum L. (red maple) showed the highest survival (65–93%) but also very high leader damage (80–97%). Acer pensylvanicum L. (striped maple) showed fairly high survival (81–93%) in all but the most exposed microsites (24–36%) and had the lowest leader damage overall (17–44%). Acer saccharum Marsh. (sugar maple) was intermediate for both survival (25–86%) and leader damage (55–96%).

Growth differed significantly among sites and species. Both intact and damaged plants showed greater growth in gaps than in understorey, particularly in large gaps. For most growth variables in most microsites, A. pensylvanicum ≥ A. rubrum > A. saccharum when plants were intact, but A. rubrum ≥ A. pensylvanicum > A. saccharum when damaged. Species differences in growth varied among sites, with large gaps producing more pronounced effects than small gaps and understorey for both intact and damaged plants.

Growth recovery was inversely related to leader damage frequency among species, and thus at least partially offset the effects of damage on net growth across the populations.

The microsite‐ and species‐specific responses to leader damage may influence gap regeneration and forest composition. A. pensylvanicum may be favoured by its regrowth advantage over A. rubrum and A. saccharum in the understorey, where damage is likely to occur during prolonged pre‐gap periods. In contrast, A. rubrum shows a decisive advantage over its congeners in regrowth in the centres of large gaps, where the probability of a juvenile tree capturing canopy gap space is highest.
Freestanding lipid bilayers as substrates for electron cryomicroscopy of integral membrane proteins
Authors: Mcalduff D. E. , Heng Y. M. , Ottensmeyer F. P.
Published: March 2003

Phospholipid bilayers, 40 Å thick, were generated as electron microscope substrates by submerging copper grids overlaid with holey plastic through a lipid monolayer on a water surface. Previously formed proteoliposomes containing single‐particle membrane proteins in their bilayers were then fused into the newly formed bilayer substrate. To demonstrate this methodology, multi‐drug resistance protein P‐glycoprotein was incorporated into these bilayers and imaged by fixed beam microscopy and scanning transmission electron microscopy.
Homogeneous repair of nuclear genes after experimental stroke
Authors: Moore N. , Okocha F. , Cui J. K. , Liu Philip K.
Published: March 2003

The repair of oxidative DNA lesions (ODLs) in the nucleus of ischemic cortical brain cells was examined following experimentally induced stroke by occluding the right middle cerebral artery and both common carotid arteries for 60–90 min followed by reperfusion in male long‐Evans hooded rats. The control group consisted of sham‐operated animals undergoing the same surgery without vessel occlusion. Using a gene‐specific assay based upon the presence of Escherichia coli Fpg protein‐sensitive sites, we noted that animals with stroke exhibited six and four ODLs per gene in the actin and DNA polymerase‐β genes, respectively. This was increased from one per four copies of each gene in the sham‐operated control (p < 0.01). One half of the initial ODLs was repaired within 30 min, and 83% of them were repaired as early as 45 min of reperfusion. There was no further increase when gene repair was measured again at 2 h of reperfusion. The rates of active repair within 45 min of reperfusion were the same in these two genes (p = 0.103, anova). BrdU (10 mg/kg) was administered via intraperitoneal injection at least one day before surgery. We observed that there was no significant incorporation of BrdU triphosphates into genomic DNA during active repair, but there were significant amounts of BrdU triphosphate in nuclear DNA after active repair. The result indicates that genomic repair of ODLs in the brain did not significantly incorporate BrdU, and the initiation of neurogenesis probably starts after the completion of repair in the brain.
Differential cell surface expression of GABAA receptor α1, α6, β2 and β3 subunits in cultured mouse cerebellar granule cells – influence of cAMP‐activated signalling
Authors: Ives Jane H. , Drewery Debra L. , Thompson Christopher L.
Published: March 2003

In this study we have used mature, primary cultured mouse cerebellar granule cells (CGCs) to initiate our studies on the mechanisms governing neuronal trafficking of GABAA receptors (GABARs). Initially the steady‐state distribution of GABAR α1, α6, β2 and β3 subunits between the cell surface and cell interior was quantified. Cell surface proteins were modified with a membrane‐impermeable cross‐linking agent, bis(sulfosuccinimidyl)suberate (BS3) or the proteolytic enzyme, chymotrypsin. The proportion of unmodified (intracellular) and modified (cell surface) subunits was quantified by immunoblotting. We found that 51% of α6, 74% of α1, and 83% of β2/3 were expressed at the cell surface, thus identifying a sizeable intracellular pool of α6 in contrast to the low levels of intracellular α1 and β2/3. Chronic activation of protein kinase A (PKA) in CGCs in vitro, post‐transcriptionally up‐regulated expression of α1, β2 and β3 but not α6. This was paralleled by an increase in the BZ‐S subtype of [3H]Ro15–4513 binding sites. GABAR α1 was increased at the cell surface and in the cell interior, β2 was increased almost exclusively at the cell surface whilst β3 was increased almost exclusively in the cell interior. The intracellular pool of α6 was not affected. Thus, GABAR subunits are subject to differentially regulated trafficking, affording yet greater scope for GABAR diversity and plasticity.
Neuroprotective properties of cannabinoids against oxidative stress: role of the cannabinoid receptor CB1
Authors: Marsicano Giovanni , Moosmann Bernd , Hermann Heike , Lutz Beat , Behl Christian
Published: March 2003

Neuroprotective effects have been described for many can‐nabinoids in several neurotoxicity models. However, the exact mechanisms have not been clearly understood yet. In the present study, antioxidant neuroprotective effects of cannabinoids and the involvement of the cannabinoid receptor 1 (CB1) were analysed in detail employing cell‐free biochemical assays and cultured cells. As it was reported for oestrogens that the phenolic group is a lead structure for antioxidant neuroprotective effects, eight compounds were classified into three groups. Group A: phenolic compounds that do not bind to CB1. Group B: non‐phenolic compounds that bind to CB1. Group C: phenolic compounds that bind to CB1. In the biochemical assays employed, a requirement of the phenolic lead structure for antioxidant activity was shown. The effects paralleled the protective potential of group A and C compounds against oxidative neuronal cell death using the mouse hippocampal HT22 cell line and rat primary cerebellar cell cultures. To elucidate the role of CB1 in neuroprotection, we established stably transfected HT22 cells containing CB1 and compared the protective potential of cannabinoids with that observed in the control transfected HT22 cell line. Furthermore, oxidative stress experiments were performed in cultured cerebellar granule cells, which were derived either from CB1 knock‐out mice or from control wild‐type littermates. The results strongly suggest that CB1 is not involved in the cellular antioxidant neuroprotective effects of cannabinoids.
Photic regulation of l‐arginine uptake in the golden hamster retina
Authors: Sáenz Daniel A. , Cymeryng Cora B. , De Nichilo Analía , Sacca Geraldine B. , Keller Sarmiento María I. , Rosenstein Ruth E.
Published: March 2003

One of the limiting steps in the regulation of nitric oxide (NO) synthesis is the availability of its precursor, l‐arginine, which depends on the presence of a specific uptake system. A characterization of the l‐arginine uptake mechanism in the golden hamster retina was performed. This mechanism was stereospecific, saturable, and monophasic, with an apparent Km of 56.1 ± 2.0 µm and a maximum velocity of 36.0 ± 2.8 pmol/mg prot/min. The basic amino acids l‐lysine and l‐ornithine but not d‐arginine or the nitric oxide synthase inhibitors, Nω‐nitro‐l‐arginine methyl ester and Nω‐nitro‐l‐arginine impaired l‐arginine influx. Preincubation with l‐lysine for 1 h prior to the transport assay significantly stimulated l‐arginine uptake. Saturation studies of l‐arginine uptake performed at 12.00 and 24.00 h indicated a higher value of Vmax at midnight than at midday. When the hamsters were placed under constant darkness or constant light for 48 h and killed at equivalent time points, representing subjective day and subjective night, the differences in l‐arginine influx disappeared. Semiquantitative RT‐PCR analysis showed that the levels of mRNAs for both CAT‐1 and CAT‐2B were significantly higher at midnight than at midday. l‐Arginine significantly increased cGMP accumulation in a time‐dependent manner, with maximal effects during the night. Based on these results, it might be presumed that hamster retinal l‐arginine uptake is regulated by the photic stimulus.
Toward understanding vesicle traffic and the guard cell model
Authors: Blatt Michael R.
Published: March 2003

Vesicular trafficking and membrane fusion are integral to cell growth and development with SNARE proteins, RabGTPases and their associates implicated in membrane fusion and secretion throughout the plant endomembrane system. Although the overall pattern of function is similar to that of animals and yeast, many aspects of endomembrane organization and vesicle trafficking appear unique to plants, for example, the control of cell and vacuolar expansion, asymmetric growth and cell division. However, the dominant membrane trafficking pathways have yet to be defined. Comparative genomics provide important information about vesicle trafficking elements but assigning biological roles based on sequence similarities is extremely difficult. Cellular and genetic approaches are reviewed here that have allowed visualization of vesicle trafficking in plants, including capacitance and dye methods, imaging and marker techniques, protein interactions and reverse genetics. Stomatal guard cells are discussed as cell models for identifying vesicle trafficking pathways and evidence points to a role for vesicle trafficking in stomatal function. For plants generally, kinetic analyses and biochemical studies suggest that several different pools of vesicles, and possibly different mechanisms for delivery, are available for vesicle traffic between endomembrane compartments and the plasma membrane. Characterizing these pathways, their functions and controls provides a major challenge for the future.
Observed and predicted changes over eight years in frequency of barley powdery mildew avirulent to spring barley in France and Denmark
Authors: Bousset L. , Hovmøller M. S. , Caffier V. , De Vallavieille‐Pope C. , Østergård H.
Published: March 2003

Aerial populations of Blumeria graminis f.sp. hordei were studied in two French and two Danish regions from 1991 to 1999, at a time of year when only winter barley was present. A high frequency of genotypes not able to grow on the spring‐sown crop of the previous growing season (denoted ‘spring‐avirulent’) was observed in most years and regions. This frequency increased with increasing proportion of winter barley; it was highest in France and decreased in general over the 8‐year period. Most of the spring‐avirulent genotypes possessed the Va22 virulence gene, matching a resistance that has never been present in barley cultivars grown in Europe. A hypothetical cropping system, including winter‐ and spring‐sown crops with three resistance genes altogether, was constructed to mimic the utilization of host cultivars in the four regions. Results from a mathematical model simulating changes in the composition of the pathogen population in this system, demonstrated that selection solely due to host resistance genes, i.e. without assuming any cost of virulence, might lead to such results as those observed. The changes in frequency of spring‐avirulent genotypes and the frequency of unnecessary virulence genes may be predicted from the proportion of the barley area sown with winter barley, the use of resistance genes in the cultivars, the initial composition of the pathogen population, and hitch‐hiking due to gametic disequilibria.
Prevalence of human parvovirus B19 in blood donors as determined by a haemagglutination assay and verified by the polymerase chain reaction
Authors: Hitzler W. E. , Runkel S.
Published: March 2003

Background and Objectives Transmission of human parvovirus B19 (PV B19) by transfusion of blood and blood products is well documented. Although PV B19 infection is connected with severe complications in some recipients, donor screening is not yet mandatory. In this study the prevalence of PV B19, as detected by a haemagglutination assay (the Human PV B19 Antigen‐Test), was assessed. In addition, the persistence of B19 DNA and the serological status of blood donors was also assessed. The specificity and utility of the Human PV B19 Antigen‐Test for donor screening was investigated and compared with other screening strategies.

Materials and Methods The prevalence of PV B19 viraemia was assessed in 28 972 donations from 15 660 remunerated donors by means of the haemagglutination assay. Reactive results were confirmed by the polymerase chain reaction (PCR).

Results Overall, 255 donations gave reactive or indeterminate results in the screening assay. Four donations/donors detected by the haemagglutination assay were confirmed as positive for B19 DNA by PCR. Therefore, a frequency was detected of 1 : 7243 B19‐positive donations and 1 : 3915 positive donors. Specificity was determined to be 99·1%. Follow‐up showed the persistence of viraemia in low concentrations for prolonged time‐periods.

Conclusion Blood donations with a high level of human PV B19 viraemia can be detected by the haemagglutination assay, which is rapid and easy to perform. The presence of neutralizing antibody may inhibit specific haemagglutination.
A comparison of cellular and humoral immune responses to trichuroid derived antigens in human trichuriasis
Authors: Turner Joseph , Faulkner Helen , Kamgno Joseph , Else Kathryn , Boussinesq Michel , Bradley Janette E.
Published: March 2003

Individuals, residing in a region highly endemic for Trichuris trichiura, were examined for cytokine and proliferative responses to T. trichiura worm homogenate (TtAg), T. trichiura excretory/secretory products (TtES) and the equivalent antigenic preparations from the murine whipworm, Trichuris muris. Serum antibody levels against TtAg, T. muris worm homogenate and T. muris ES products were also studied. Measurable levels of immunoglobulin (Ig)G1, IgG4, IgA and IgE against T. muris antigens were detected, indicating a degree of conservation of epitopes between antigens derived from both species. Although levels of interleukin (IL)‐4, IL‐10, IL‐13, tumour necrosis factor (TNF)‐α and proliferative responses produced were comparable between homogenate antigens of either species and ES antigens of either species, a markedly different cellular response was observed in cultures stimulated with homogenate antigens compared to ES antigens. ES antigens preferentially induced IL‐10 (P > 0·001) and TNF‐α (P > 0·001) production, whereas levels of IL‐4 (P > 0·001), IL‐13 (P > 0·001) and proliferative responses (P > 0·001) were greater in cultures stimulated with whole worm extracts. Our findings suggest that T. muris preparations could be used as an alternative to T. trichiura proteins as a source of antigens in ex vivo cultures and that ES products stimulate a distinct immune response compared to somatic antigens.
Effects of instrumentation, irrigation and dressing with calcium hydroxide on infection in pulpless teeth with periapical bone lesions
Authors: Peters L. B. , Van Winkelhoff A.‐J. , Buijs J. F. , Wesselink P. R.
Published: March 2003

Aim The aim of this study was to evaluate the fate of microorganisms in root canals of teeth with infected pulps and periapical bone lesions with and without the use of calcium hydroxide medication.

Methodology Endodontic samples were cultured and microorganisms were counted and identified in 43 teeth before (sample 1) and after (sample 2) treatment during the first visit and before (sample 3) and after (sample 4) treatment during the second visit. In the first visit teeth were instrumented and half of the teeth were filled with a thick slurry of calcium hydroxide in sterile saline. The other teeth were obturated with gutta‐percha and AH‐26 sealer. After 4 weeks the teeth with calcium‐hydroxide were accessed again and after microbiological sampling they were obturated with gutta‐percha and AH‐26 sealer.

Results The mean total colony forming unit (CFU) counts of positive samples dropped significantly as a result of canal preparation during the first visit from 1.0 × 106 to 1.8 × 103 (between samples 1 and 2) but increased to 9.3 × 103 in the period between the two visits (sample 2 and 3). There was no difference in mean total CFU counts of positive samples between the end of the first (sample 2) and the end of the second visit (sample 4). The most frequently isolated species were Prevotella intermedia, Capnocytophaga spp., Actinomyces odontolyticus, Propionibacterium acnes and Peptostreptococcus micros.

Conclusions Although a calcium hydroxide paste was placed in the prepared canals, the number of positive canals had increased in the period between visits. However, the number of microorganisms had only increased to 0.93% of the original number of CFU (sample 1). It is concluded that a calcium hydroxide and sterile saline slurry limits but does not totally prevent regrowth of endodontic bacteria.
Visualisation and animation in a CAL package: anchors or misconceptions?
Authors: Lim C.P.
Published: March 2003

Abstract Various studies have shown that visualisation and animation in CAL packages offer students with effective ‘conceptual anchors’ to hook their thinking onto. This paper examines the role of these visual representations of a CAL package in an economics course, and argues for the design and organisation of instructional activities to exploit the cognitive opportunities and address the limitations of these representations. In other words, a holistic approach to visualisation and animation is required to serve as conceptual anchors rather than sources of misconceptions.
Practice characteristics that lead to 21st century learning outcomes
Authors: Law N. , Lee Y. , Chow A.
Published: March 2003

Abstract The key research question for this study was to ask whether or not innovative teaching practices would lead to the development of learning outcomes essential for preparing the younger generation for the challenges of life in the knowledge society of the 21st century, and if so, how are the pedagogical features related to the different learning outcomes. Preliminary analyses of the case study data collected from the SITES M2 Study in Hong Kong reveal that where the development of more significant learning gains were observed, the cases possess characteristics additional to the criteria defined in the Study for selection of innovation. More importantly, it was found that the impact of the pedagogical practices was not determined simply by the aggregation of characteristics of the practices per se, nor on the technologies used, but on whether ‘empowerment’ permeates the curriculum goal and process. Further, this paper claims that these affective and socio‐cognitive learning outcomes are more important as preparation for lifelong learning in the 21st century than ‘knowledge management competencies’.
Innovative pedagogical practices using ICT in schools in England
Authors: Harris S.
Published: March 2003

Abstract This paper presents information about the case studies carried out in three primary and three secondary schools in England, during the school year 2000–2001. Data were collected as part of the qualitative phase of a major international research project: the Second Information Technology in Education Study (SITES). The research focused on innovative pedagogical practices involving ICT. Interviews with Headteachers and other administrators, teachers, students and parents; observations of lessons; analysis of school documents and surveys of Headteachers and ICT coordinators provided rich sources. Themes common to the case studies in England are identified and discussed.
A simple method for calculating mosquito mortality rates, correcting for seasonal variations in recruitment
Authors: Briët O. J. T.
Published: March 2003

Abstract A simple age‐structured exponential growth model is presented for the analysis of the population dynamics of mosquitoes (Diptera: Culicidae). In this model, the proportion of parous mosquitoes R depends on the birth rate β, and the length of the first gonotrophic cycle g, but not on the mortality rate. If the age structure is fairly constant, R= exp(– βg). Extensions of the model correcting for feeding patterns are given. A simple method is applied to an example of Anopheles gambiae Giles biting density and parity ratio in Côte d'Ivoire (fortnightly sampled longitudinal data set), for calculation of the seasonally fluctuating mortality rate, correcting for effects of recruitment. The seasonal variations in birth rate and mortality rate are discussed in relation to variations in density and rainfall.
A new species of Triatominae from Tamil Nadu, India
Authors: Galvão C. , Patterson J. S. , Da Silva Rocha D. , Jurberg J. , Carcavallo R. , Rajan K. , Ambrose D. P. , Miles M. A.
Published: March 2003

Abstract A new species of the genus LinshcosteusDistant, 1904 (Hemiptera: Reduviidae: Triatominae) is described from specimens collected near Kalakkadu, Tamil Nadu state, southern India. Specimens were found in deep crevices between rocks, in a region of semi‐arid scrub jungle. The distinctiveness of the new species was demonstrated by a morphometric analysis including the five previously described species of Linshcosteus, all from India. Nine measurements of the head were used in an isometric size‐free principal component analysis. In terms of discrete morphology the new species, Linshcosteus karupus sp.n. Galvão, Patterson, Rocha & Jurberg differs from the most similar one, L. kaliLent & Wygodzinsky, 1979, by its very prominent anterolateral projections of the pronotum, by the length to width ratio of the pronotum, by the pilosity of the head and several other characters, including phallic structures. A revised key is presented for the six species of the genus.
The mitochondrial toxin 3‐nitropropionic acid induces differential expression patterns of apoptosis‐related markers in rat striatum
Authors: Vis J. C. , Verbeek M. M. , De Waal R. M. W. , Ten Donkelaar H. J. , Kremer B.
Published: March 2003

The mitochondrial toxin 3‐nitropropionic acid (3‐NP) causes selective striatal lesions in rats and serves as an experimental model for the neurodegenerative disorder Huntington's disease (HD). Apoptotic cell death has been implicated for the neuronal degeneration that occurs in HD brains. The present study was designed to investigate whether the 3‐NP‐induced cell death in rats involves apoptosis and an altered expression of Bcl‐2 family proteins. Systemic administration of 3‐NP via subcutaneous Alzet pumps resulted in lesions of variable severity with neuronal loss and gliosis in the striatum. Using the terminal transferase‐mediated biotinylated‐UTP nick end‐labelling (TUNEL) of DNA, TUNEL‐positive cells exhibiting typical apoptotic morphology were detected only in the striatum of rats with a severe lesion. Furthermore, the neuronal expression of the pro‐apoptotic protein Bax was strongly increased in the core of the severe lesion. Expression of the anti‐apoptotic marker Bcl‐2 was unchanged in this location, but was enhanced in the margins of the lesions. A moderately increased expression of both Bax and Bcl‐2 was observed in dark neurones in the mild lesion and in the subtle lesion. The presence of nuclear DNA fragmentation, strong granular Bax expression and an increased Bax/Bcl‐2 ratio in the centre of severe lesions suggests the occurrence of apoptotic cell death following 3‐NP administration. In contrast, the dark compromised neurones observed in 3‐NP‐treated animals revealed an equally enhanced expression of both Bax and Bcl‐2, but lacked TUNEL‐labelling, and are therefore not apoptotic.
Are fecundity and longevity of female Aphelinus abdominalis affected by development in GNA‐dosed Macrosiphum euphorbiae?
Authors: Couty A. , Clark S. J. , Poppy G. M.
Published: March 2003

Abstract. Snowdrop lectin (Galanthus nivalis agglutinin, GNA) confers partial resistance to several aphid species when incorporated into an artificial diet and/or expressed in transgenic potato. First‐tier laboratory‐scale experiments were conducted to assess the potential effect of GNA on the longevity and fecundity of female parasitoid Aphelinus abdominalis (Dalman) that had developed in Macrosiphum euphorbiae (Thomas) fed artificial diet containing 0.1% GNA (w/v). In a previous study it was shown that GNA ingested by A. abdominalis larvae is not acutely toxic. It was also shown that GNA has a host‐size mediated effect on parasitoid sex ratio and larval development, but no apparent direct effect.     In this study, we report that A. abdominalis larvae that developed in GNA‐dosed aphids that were smaller than control aphids of the same age, produced smaller adults with a reduced longevity and fecundity. Aphelinus abdominalis larvae that developed in GNA‐dosed aphids older than the control but of the same size, produced adults of similar size that lived as long as the control but had a reduced fecundity.     Our results suggest that GNA fed to aphids in artificial diet has both a host‐mediated effect (via aphid‐size) and a direct effect on adult parasitoid fecundity. It is not known how GNA affects parasitoid larval development and subsequently adult fecundity, but it is hypothesized that GNA acted as an antifeedant to parasitoid larvae, thus disturbing nutrient assimilation and conversion necessary for egg maturation.
Ectoparasites do not affect ejaculate volume in the dragonflyCoenagrion puella
Authors: Rolff Jens , Braune Pia , Siva‐Jothy Michael T.
Published: March 2003

Abstract.Imagoes of the dragonflyCoenagrion puellaare parasitized frequently by ectoparasitic water mites. In an experimental study of the parasite load we examined the influence of parasite burden on host sperm volume. Infection with ectoparasitic water mites did not affect sperm volume in the seminal vesicle (ejaculate volume). It is concluded that water mite parasitism does not affect male fitness inC. puellaby reducing sperm production.
Behavioural responses of Varroa destructor (Acari: Varroidae) to extracts of larvae, cocoons and brood food of worker and drone honey bees, Apis mellifera (Hymenoptera: Apidae)
Authors: Calderone Nicholas W. , Lin Sisi
Published: March 2003

Abstract. Varroa destructor is a parasitic mite of the honey bee species Apis cerana Fabr. and A. mellifera L. Mature females reproduce on the immature stages of their hosts, producing more viable female offspring on drone hosts than on worker hosts. Thus, immature drones are more likely to be infested with mites than immature workers. To investigate the hypothesis that differences in host chemistries underlie the biased distribution of mites between worker and drone brood, the arrestment responses of mites to solvent extracts of a number of stimuli normally encountered by a mite during its life cycle were measured. Mites were arrested by cuticular extracts of worker and drone larvae obtained at 0, 24 and 48 h prior to the time when cell capping is completed. Mites were also arrested by extracts of worker and drone, brood food and cocoons, and by a blend of synthetic fatty acid esters previously shown to be active in the host acquisition process. In a wind tunnel bioassay, mites were attracted to odours from living fifth‐instar worker and drone larvae, but not to volatiles from cocoons, brood food or a blend of fatty acid esters. The sex of the host was not an important factor affecting the behavioural responses of the mites in any assay. We conclude that host kairomones play a role in the host acquisition process, but we found no evidence to support the hypothesis that mites use these substances to differentiate between worker and drone brood.
Preservative systems containing essential oils in cosmetic products
Authors: Maccioni A. M. , Anchisi C. , Sanna A. , Sardu C. , Dessì S.
Published: March 2003

Synopsis

The aim of this study was to evaluate the antimicrobial activity of selected essential oils (Laurus nobilis, Eucalyptus globulus and Salvia officinalis), both alone and in combination, in cosmetic preparations characterized by an increasing risk of microbial contamination, i.e. an O/W skin cream, a hydrogel and a non‐alcoholic hydrolyte. Their potential synergistic effect in combination with the usual cosmetic preservatives at low concentrations (up to 200‐fold less than usual) was also investigated.
A Portrait: Magdalena's Dream
Authors: Averill Jennifer B.
Published: March 2003

A recent critical ethnographic study examined the effects of the health care system, historical exploitation, socioeconomic factors, and cultural values on retired migrant farm workers in northeastern Colorado. Combining ethnographic interviews, participant observation, photography, and critical analysis, study findings indicated a need to increase the cultural knowledge and collaborative efforts of health care providers. Emerging from the study, this article presents a creative composite vignette of retired migrant farm workers. The narrative and photograph offer testimony to the lived experience of these rural older Hispanic persons. The intent of the story is to provide the readers with deepened understanding of the hardships, social ostracism, economic challenges, personal hardiness, and cultural values that are characteristic of this special population.
Social Justice or Market Justice? The Paradoxes of Public Health Partnerships with Managed Care
Authors: Drevdahl Denize
Published: March 2003

Public health is increasingly joining forces with managed care, yet the effect of this partnership on public health nursing (PHN) has received little scrutiny. The feasibility and consequences of a public–private alliance raise questions about whether the mission of public health can be sustained in a managed care system and whether managed care's approaches to health care are conducive to providing population‐oriented care. Expanding the links between PHN and private organizations is both problematic and promising. Managed care organizations have much to offer, including coordination of services and comprehensive care. However, they may also restrict coverage and create bureaucratic obstacles to obtaining services. The growth of for‐profit health care corporations evokes questions about ways in which concern for communities and populations collide with stockholder interests. The task for PHN is to recognize and to dialogue about these complexities so that nursing's voice can be heard as solutions to these dilemmas are created.
Degenerative mucinotic mural folliculitis in cats
Authors: Gross Thelma Lee , Olivry Thierry , Vitale Carlo B. , Power Helen T.
Published: March 2003

A novel form of mural folliculitis is described in seven cats. Clinically, all cats exhibited generalized alopecia with scaling or crusting that was more pronounced over the head, neck, and shoulders. The face and muzzle of all cats was unusually thickened. Six of seven cats were progressively lethargic but did not demonstrate any other consistent systemic abnormalities. Histologically, there was severe mixed inflammation of the wall of the follicular isthmus in all cats, accompanied by some follicular destruction in five cats. Sebaceous glands were not affected. All cats had variable, but often striking, follicular mucin deposition, as well as epidermal hyperkeratosis and crusting. The cause of the severe mural folliculitis was not identified, and all cats responded poorly to immunomodulating therapy. Follicular mucinosis may be a nonspecific finding, likely reflective of the follicular lymphocytic milieu, and does not always herald follicular lymphoma.
Evaluation of the palate dimensions of patients with perennial allergic rhinitis
Authors: De Freitas F. C. N. , Bastos E. P. , Primo L. S. G. , De Freitas V. L. N.
Published: March 2003

Objective. The purpose of this study was to compare the transverse and vertical palate dimensions of two groups of children, one diagnosed as having perennial allergic rhinitis (PAR) and the other without any respiratory pathology.

Design. Case‐control study.

Setting. Institute of Paediatrics and Child Care of the Federal University of Rio de Janeiro.

Sample and Methods. The sample consisted of 101 children with the diagnoses of PAR (mean age 6·5) and 91 without any respiratory pathology (mean age 7·3). From 192 patients, 65% was in mixed dentition phase and 35% in primary dentition. Each subject underwent an intra‐oral clinical examination using three‐dimensional Korkhaus compass to measure the intermolar distance, intercanine distance and palate depth.

Results. The allergic group showed greater averages of palate depth (P = 0·00), both in the primary dentition phase (11·53 mm × 10 mm) and in the mixed dentition (11·96 mm × 10·21 mm). There was no statistically significant difference for intermolar and intercanine distances, either in primary or mixed dentition (P > 0·05).

Conclusion. The transverse dimension of the palate did not vary significantly between the groups, which seems to confirm that the main influence of alteration of the breathing pattern from nasal to mouth occurs on the vertical plane.