bluuebunny/crossref_metadata_2025 huggingface dataset:
A case of complex odontoma associated with an impacted lower deciduous second molar and analysis of the 107 odontomas
Authors: Hisatomi M , Asaumi J‐i , Konouchi H , Honda Y , Wakasa T , Kishi K
Published: March 2003

OBJECTIVE: Odontoma is a comparatively common odontogenic tumor, and it may lead to interference with the eruption of its associated tooth. Odontomas are mostly associated with permanent teeth, and they are rarely associated with deciduous teeth. The purpose of this report is to analyze 107 odontomas and to present a case of complex odontoma associated with a lower deciduous second molar.

SUBJECT AND METHODS: The 106 cases were analyzed with regard to the following parameters: age, gender, location, erupted teeth, congenital missing teeth, radiological features, histopathological features and prognosis.

RESULTS: Of the 106 cases, 41 were complex odontoma, 62 were compound odontoma, and three were immature odontoma. Compound odontoma had a predilection for the anterior. Complex odontoma occurred more often at the mandible.

CONCLUSION: Odontoma located above the tooth crown of lower deciduous molar did not behave clinically different from that associated with permanent tooth. An odontoma could be related with a supernumerary tooth or a missing tooth. If odontomas, which interfered with tooth eruption, were extirpated early, the impacted teeth would probably erupt normally and be normal in shape.
Salivary IgA and IgG subclasses in oral mucosal diseases
Authors: Sistig S , Vučićević‐Boras V , Lukač J , Kusić Z
Published: March 2003

OBJECTIVE: It was hypothesized that serum levels of immunoglobulins may play a role in the pathogenesis of oral mucosal diseases, or reflect clinical changes in these conditions, but little is known about the role of salivary immunoglobulins in the pathogenesis of these diseases. The aim of this study was to investigate possible alterations in salivary immunoglobulin A (IgA) and IgG subclasses in patients with oral mucosal inflammatory diseases.

SUBJECTS and METHODS: Levels of IgG1, IgG2, IgG3 and IgG4 were determined by enzyme‐linked immunosorbent assay (ELISA), and IgA1 and IgA2 by radial immunodiffusion in the resting whole saliva of 31 patients with acute recurrent aphthous ulceration (RAU) (and followed in remission), 11 patients with chronic hyperplastic candidal infection (CHC), 12 patients with Sjögren's syndrome (SS), six patients with oral lichen planus (OLP), and 18 healthy volunteers using the normal saliva as a comparison point for all.

RESULTS: IgG and IgA subclasses were increased in OLP. In CHC all IgG subclasses were increased while IgA1 was decreased, IgG1, IgG3 and IgG4 levels were increased in SS, while all IgG subclasses as well as IgA2 were increased in acute RAU in comparison with healthy controls. No differences in any immunoglobulin subclasses between major and minor acute RAU were found. In remission, IgG1 and IgG4 returned to normal values while IgG2, IgG3, and IgA2 remained increased in patients with RAU.

CONCLUSION: Salivary immunoglobulin subclasses vary in different oral mucosal conditions and may play a role in oral mucosal inflammatory diseases and/or reflect clinical changes in these conditions.
A point mutation in the UDP-glucose pyrophosphorylase gene results in decreases of UDP-glucose and inactivation of glycogen synthase
Authors: HIGUITA Juan-Carlos , ALAPE-GIRÓN Alberto , THELESTAM Monica , KATZ Abram
Published: March 2003

The regulatory role of UDP-glucose in glycogen biogenesis was investigated in fibroblasts containing a point mutation in the UDP-glucose pyrophosphorylase gene and, consequently, chronically low UDP-glucose levels (Qc). Comparisons were made with cells having the intact gene and restored UDP-glucose levels (G3). Glycogen was always very low in Qc cells. [14C]Glucose incorporation into glycogen was decreased and unaffected by insulin in Qc cells, whereas insulin stimulated glucose incorporation by 50% in G3 cells. Glycogen synthase (GS) activity measured in vitro was virtually absent and the amount of enzyme in Qc cells was decreased by about 50%. The difference in GS activity between cells persisted even when G3 cells were devoid of glycogen. Incubation of G3 cell extracts with either exogenous UDP-glucose or glycogen resulted in increases in GS activity. Incubation of Qc cell extracts with exogenous UDP-glucose had no effect on GS activity; however, incubation with glycogen fully restored enzyme activity. Incubation of G3 cell extracts with radioactive UDP-glucose resulted in substantial binding of ligand to immunoprecipitated GS, whereas no binding was detected in Qc immunoprecipitates. Incubation of Qc cell extracts with exogenous glycogen fully restored UDP-glucose binding in the immunoprecipitate. These data suggest that chronically low UDP-glucose levels in cells result in inactivation of GS, owing to loss of the ability of GS to bind UDP-glucose.
Genomic organization and transcriptional analysis of the human l-glutaminase gene
Authors: PÉREZ-GÓMEZ Cristina , MATÉS José M. , GÓMEZ-FABRE Pedro M. , CASTILLO-OLIVARES Antonio del , ALONSO Francisco J. , MÁRQUEZ Javier
Published: March 2003

In mammals, glutaminase (GA) is expressed in most tissues, but the regulation of organ-specific expression is largely unknown. Therefore, as an essential step towards studying the regulation of GA expression, the human liver-type GA (hLGA) gene has been characterized. LGA genomic sequences were isolated using the genome walking technique. Analysis and comparison of these sequences with two LGA cDNA clones and the Human Genome Project database, allowed the determination of the genomic organization of the LGA gene. The gene has 18 exons and is approx. 18kb long. All exon/intron junction sequences conform to the GT/AG rule. Progressive deletion analysis of LGA promoter—luciferase constructs indicated that the core promoter is located between nt −141 and +410, with several potential regulatory elements: CAAT, GC, TATA-like, Ras-responsive element binding protein and specificity protein 1 (Sp1) sites. The minimal promoter was mapped within +107 and +410, where only an Sp1 binding site is present. Mutation experiments suggested that two CAAT recognition elements near the transcription-initiation site (-138 and −87), play a crucial role for optimal promoter activity. Electrophoretic mobility-shift assays confirmed the importance of CAAT- and TATA-like boxes to enhance basal transcription, and demonstrated that HNF-1 motif is a significant distal element for transcriptional regulation of the hLGA gene.
Targeting of alpha-kinase-anchoring protein (alphaKAP) to sarcoplasmic reticulum and nuclei of skeletal muscle
Authors: NORI Alessandra , LIN Pei-Ju , CASSETTI Arianna , VILLA Antonello , BAYER K.-Ulrich , VOLPE Pompeo
Published: March 2003

The sarcoplasmic reticulum (SR) plays a key role in excitation/contraction coupling of skeletal muscle. The SR is composed of two continuous yet heterogeneous membrane compartments, the free or longitudinal SR and cisternal SR. Cisternal SR is made up of free SR membrane, enriched in Ca2+ pumps, and junctional SR (jSR) membrane, enriched in ryanodine-sensitive Ca2+-release channels, and contains calsequestrin within its lumen. Protein phosphorylation mediated by the Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) has significant, distinct regulatory roles in both Ca2+ uptake and Ca2+ release. Kinase-anchoring proteins (KAPs) constitute a novel mechanism for achieving cell compartmentalization of effectors in phosphorylation pathways. Here, targeting of αKAP, a CaM kinase II-anchoring protein encoded within the α-CaM kinase II gene, was studied in transgenic skeletal muscle fibres of the adult rat soleus. The transgenes were epitope-tagged versions of αKAP and of a deletion mutant, allowing their specific immunodetection against the wild-type background. Our results show that αKAP is largely localized at the free SR and thus near the Ca2+ pump, a protein that can be modulated by CaM kinase II phosphorylation. Only minor co-localization was observed with the jSR ryanodine-sensitive Ca2+-release channel, which is a potential CaM kinase II target. In non-muscle cells, recombinant αKAP is targeted to endoplasmic reticulum (ER). Both ER and SR targeting requires the N-terminal hydrophobic region of αKAP. An unexpected additional specific localization that does not require the N-terminus was found in the nucleus, providing a first clue of how CaM kinase II can fulfil its nuclear functions in skeletal muscle.
Chronic Pain, Chronic Stress and Depression: Coincidence or Consequence?
Authors: Blackburn‐Munro G. , Blackburn‐Munro R. E.
Published: March 2003

Chronic pain and depressive illness are debilitating disease states that are variably resistant to currently available therapeutic agents. Animal models of chronic pain are associated with activation of the hypothalamo‐pituitary‐adrenal (HPA) axis, upon which chronic pain acts as an inescapable stressor. Inescapable stress is also associated with ‘depressive‐like’ symptoms in experimental animals. Based on reports of the comorbidity between chronic pain and depressive illness in human patients, it is possible that these disease states are linked, via chronic stress‐induced HPA dysfunction. Here, we discuss the possible involvement of the HPA axis in the aetiology of both chronic pain and clinical depression, and suggest a strategy for the development of novel pharmacotherapies.
Calcium transients in response to salinity and osmotic stress in the nitrogen‐fixing cyanobacterium Anabaena sp. PCC7120, expressing cytosolic apoaequorin
Authors: Torrecilla I. , Leganés F. , Bonilla I. , Fernández‐Piñas F.
Published: March 2003

We show here that both salinity and osmotic stress trigger transient increases in intracellular free Ca2+ concentration ([Ca2+]i) in cells of the nitrogen‐fixing filamentous cyanobacterium Anabaena sp. PCC7120, which constitutively expresses apoaequorin. Isoosmolar concentrations of salt (NaCl) and osmoticum (sucrose) induced calcium transients of similar magnitude and shape, suggesting that cells sense, via Ca2+ signalling, mostly osmotic stress. The Ca2+ transients induced by NaCl and sucrose were completely blocked by the calcium chelator ethylene glycol‐bis(b‐aminoethylether)N,N,N¢,N¢‐tetraacetic acid (EGTA) and were partially inhibited by the calcium channel blocker verapamil. Increased external Ca2+ and the Ca2+ ionophore calcimycin (compound A23187) enhanced Ca2+ influx further, suggesting the involvement of extracellular Ca2+ in the observed response to salinity and osmotic stress. However, the plant hormone abscisic acid (ABA) did not provoke any effect on the Ca2+ transients induced by both stresses, indicating that it may not be acting upstream of Ca2+ in the signalling of salinity and/or osmotic stress in Anabaena sp. PCC7120.
Acid invertase is predominantly localized to cell walls of both the practically symplasmically isolated sieve element/companion cell complex and parenchyma cells in developing apple fruits
Authors: Zhang D. P. , Lu Y. M. , Wang Y. Z. , Duan C. Q. , Yan H. Y.
Published: March 2003

The acid invertase (β‐fructosidase, EC 3·2·1·26) was localized at subcellular level via immunogold electron microscopy in the phloem‐unloading zone of developing apple fruit. The enzyme (immunogold particles) was found to reside predominantly in the cell walls of the sieve element/companion cell (SE/CC) complex, phloem parenchyma cells and other parenchyma cells. There was almost no gold particle found in cytoplasm and vacuole. This distribution pattern remained unchanged throughout the growing season, but the enzyme numbers varied. The density of immunogold particles increased during fruit development. The immunoblotting of soluble and insoluble acid invertases provided a supporting proof for the assays of immunolocalization. The biochemical analysis showed a predominantly cell‐wall‐distributed activity of acid invertase that corresponds essentially with its amount distribution. The ultrastructural observations showed that there were numerous plasmodesmata between the parenchyma cells, but almost no plasmodesmium between the SE/CC complex and its surrounding parenchyma cells, practically resulting in the symplasmic isolation of the SE/CC complex. It is therefore suggested that the unloading pathway of sucrose from the SE/CC complex may be predominantly apoplasmic in the developing apple fruit, and that the unloaded sucrose may be hydrolysed by the functional acid invertase localized in the cell wall before it is loaded in sink cells.
Effects of mycorrhizal infection, soil phosphorus availability and fruit production on the male function in two cultivars of Lycopersicon esculentum
Authors: Poulton J. L. , Koide R. T. , Stephenson A. G.
Published: March 2003

The effects of mycorrhizal infection, soil P availability and fruit production on the male function of reproduction were examined in two cultivars of tomato (Lycopersicon esculentum Mill.). Tomato plants were grown in a greenhouse under three treatment combinations: non‐mycorrhizal, low P (NMPO); non‐mycorrhizal, high P (NMP3); and mycorrhizal, low P (MPO). In addition, all treatment combinations were grown both with and without fruit. Fruit production decreased final leaf biomass, flower production and in vitro pollen tube growth rates, often reducing the beneficial effects of increased P uptake. Thus, fruit production diverted resources from subsequent vegetative growth, flower production and pollen development. As the growing season progressed, mean pollen production per flower and in vitro germination and tube growth decreased. Mycorrhizal infection and high soil P conditions increased final leaf biomass, flower production, mean pollen production per flower (in one cultivar) and in vitro pollen tube growth rates. Thus, mycorrhizal infection and high soil P conditions increased pollen quantity and quality, thereby enhancing fitness through the male function. Similar trends in these treatments suggested that mycorrhizal effects on the male function were largely the result of improved P acquisition.
Cell wall‐associated isoflavonoids andβ‐glucosidase activity inLupinus albusplants responding to environmental stimuli
Authors: Piślewska M. , Bednarek P. , Stobiecki M. , Zieliśska M. , Wojtaszek P.
Published: March 2003

Plants respond to various biotic or abiotic stimuli with different mechanisms and the mobilization of phenolic compounds is one of them. In white lupin (Lupinus albusL.) plants, isoflavones and their glucosides were localized in cell walls where the high constitutive activity ofβ‐glucosidase (EC 3·2·1·21) was also identified. The enzyme was partially purified from root cell walls. Its polymeric active form has 180 or 200 kDa as determined by non‐denaturing electrophoresis and gel filtration, respectively, and the isoelectric point is at pH 6·9. The enzyme is an exoglucosidase, preferentially hydrolysing conjugates of phenolic compounds withβanomers of glucose. It is not active against purified lupin cell walls. The specificβ‐glucosidase activity varies in different tissues with the highest one in roots, and always higher in cell walls than in protoplast. The cell wall location of the enzyme was confirmed biochemically by its activity in intercellular washing fluids. Both aglycones and glycosides were also present in these fluids. The specificβ‐glucosidase activity correlated well with the isoflavonoid aglycone/glycoside ratios in various tissues: the higherβ‐glucosidase activity, the higher relative aglycone content.β‐glucosidase activity was found to be inducible under conditions of yeast elicitor treatment. Induction of the enzyme was accompanied by changes in the isoflavone secretion and accumulation, suggesting the regulatory role ofβ‐glucosidase activity in root exudation of isoflavonoids. No correlation however, was found between changes inβ‐glucosidase activity and the presence of isoflavonoids in root exudates of plants grown under various nitrogen nutrition regimes.
Similarity and diversity in adventitious root anatomy as related to root aeration among a range of wetland and dryland grass species
Authors: McDonald M. P. , Galwey N. W. , Colmer T. D.
Published: March 2003

Assessments of the anatomy, porosity and profiles of radial O2 loss from adventitious roots of 10 species in the Poaceae (from four subfamilies) and two species in the Cyperaceae identified a combination of features characteristic of species that inhabit wetland environments. These include a strong barrier to radial O2 loss in the basal regions of the adventitious roots and extensive aerenchyma formation when grown not only in stagnant but also in aerated nutrient solution. Adventitious root porosity was greater for plants grown in stagnant compared with aerated solution, for all 10 species in the Poaceae. The ‘wetland root’ archetype was best developed in Oryza sativa and the two species of the Cyperaceae, in which the stele contributed less than 5% of the root cross‐sectional area, the cells of the inner cortex were packed in a cuboidal arrangement, and aerenchyma was up to 35–52%. Variations of this root structure, in which the proportional and absolute area of stele was greater, with hexagonal arrangements of cells in the inner cortex and varying in the extent of aerenchyma formation, were present in the other wetland species from the subfamilies Pooideae, Panicoideae and Arundinoideae. Of particular interest were Vetiveria zizanoides and V. filipes, wetland grass species from the tribe Andropogoneae (the same tribe as sorghum, maize and sugarcane), that had a variant of the root anatomy found in rice. The results are promising with regard to enhancing these traits in waterlogging intolerant crops.
Sex ratio in relation to timing of breeding, and laying sequence in a dimorphic seabird
Authors: Velando Alberto , Graves Jeff , Ortega‐Ruano Jose E.
Published: March 2003

When the cost of rearing sons and daughters differs and the subsequent survival and reproductive success of one sex is more dependent than the other, on the amount of parental investment, adult females tend to produce more chicks of the more dependent sex if the females are in good condition themselves. One method of varying the total investment in each sex is through modifying the sex ratio of offspring produced. This study shows that in broods of European ShagsPhalacrocorax aristotelis, the sex ratio varied with laying date. Presumably in this species, the lifetime reproductive success of males is more dependent on the level of parental investment. Early breeders are in better condition, the brood sex ratio of early broods was male biased (0.63), while that of late broods was female biased (0.36). The overall difference in sex ratio found between early and late nests could be attributed to manipulation of sex in the first laid egg. In early broods, 77% of the first hatched chicks were male but only 30% of the first hatched chicks in late broods were male. The sex combination of the first two chicks in a brood significantly affected growth as measured by asymptotic mass.
Body protein does not vary despite seasonal changes in fat in the White StorkCiconia ciconia
Authors: Michard‐Picamelot Delphine , Zorn Thierry , Gendner Jean‐Paul , Mata Astolfo J. , Maho Yvon Le
Published: March 2003

To understand how a large soaring bird, the White StorkCiconia ciconia, copes with energy constraints, we compared changes in body mass in 14 captive adult storks with the body composition of 12 free‐ranging adult storks found dead from accidents. The captive storks, already in an enclosure for several years, were fedad libitum. They were weighed daily for 1.5–3.5 years using an automatic device. The bodies of the accidentally killed storks were analysed to determine total water, lipid, protein and ash contents, and to assess the biochemical composition of certain organs. Females were on average 20% lighter and 24% smaller than males, but the body mass of the sexes varied in parallel throughout the year. Body mass peaked in December and January (25–30% above minimal body mass), due essentially to large fat stores in subcutaneous and abdominal adipose tissues. Body mass and body lipid rapidly decreased from February to June, whether the storks reared chicks successfully or not, and remained minimal for a few days into July. In contrast to birds using flapping flight, no variation in body protein or pectoral muscle protein was observed while breeding, even though the moult occurred then, nor in August, before the time when wild storks migrate. An endogenous regulation of body fuels is discussed.
Reduced genetic variation in Norwegian Peregrine Falcons Falco peregrinus indicated by minisatellite DNA fingerprinting
Authors: Lifjeld Jan T. , Bjørnstad Gro , Steen Oodd F. , Nesje Marit
Published: March 2003

The Scandinavian Peregrine Falcon Falco peregrinus population went through a severe population bottleneck during the second half of the twentieth century, and was almost extinct during the 1970s. This event may have reduced the amount of genetic variation in the population. With this background, a comparative study, using multilocus, minisatellite DNA fingerprinting, was carried out on broods of the Peregrine Falcon, the Merlin Falco columbarius and the Eurasian Hobby Falco subbuteo from south‐east Norway. Band‐sharing analysis of DNA fingerprints was used to test whether broods of Peregrine Falcons showed a greater between‐nest similarity in their fingerprint profiles than did broods of the two congeneric species breeding in the same region, which have not undergone any recent population bottlenecks. The results show that broods of Peregrine Falcons were significantly more similar to each other genetically than were broods of either Merlins or Eurasian Hobbies. Furthermore, there was a positive correlation between the similarity in minisatellite DNA and the similarity in a set of 11 microsatellite loci analysed for a subset of the Peregrine Falcon samples. The correlation supports the assumption that minisatellite fingerprints provide a reliable indicator of overall genetic similarity, i.e. relatedness, between breeding pairs in the population. Hence we can conclude that broods of Peregrine Falcons were genetically more related to each other than were broods of the other two species. The high similarity in minisatellite DNA between broods indicates a loss of genetic variation in the Peregrine Falcon population caused by the bottleneck, but this explanation can only be verified through a comparative genetic study of individuals sampled before and after the bottleneck event.
Predicting distributions of Mexican birds using ecological niche modelling methods
Authors: Peterson A. Townsend , Ball Lisa G. , Cohoon Kevin P.
Published: March 2003

We tested the utility of the modelling program Genetic Algorithm for Rule‐set Prediction (GARP) for modelling ecological niches to make accurate predictions of geographical distributions for 25 bird species across Mexico. Specimen‐based point‐occurrence data were entered into the algorithm in the form of geographical coordinates, and related to digitized maps of environmental variables, including mean annual precipitation, elevation, mean annual temperature, and potential vegetation. Two Mexican states were used as test areas by withholding their points from model construction; these points were later overlaid on predictions to measure model performance. Statistically, most models (78–90%) were significantly more powerful than random models in predicting occurrences in test states; model failures were most often due to low sample size for testing, rather than an inability to model distributions of particular species. The success of this test indicates that ecological niche modelling approaches such as GARP provide a promising tool for exploring a broad range of questions in ecology, biogeography and conservation.
Medroxyprogesterone acetate enhances in vivo and in vitro antibody production
Authors: Vermeulen Mónica , Pazos Patricia , Lanari Claudia , Molinolo Alfredo , Gamberale Romina , Geffner Jorge R. , Giordano Mirta
Published: March 2003

In the present study we examine the effects of medroxyprogesterone acetate (MPA) on the specific antibody secretion to T‐dependent antigens. Our results show that the in vivo administration of MPA to mice, 7 or 90 days before immunization with sheep red blood cells (SRBC), significantly enhanced both, primary and secondary antibody responses, without affecting delayed‐type hypersensitivity (DTH). These effects could be counteracted by the anti‐progestin onapristone or ZK 98299 (ZK) suggesting that MPA interacted with progesterone (PRG) receptors to increase B‐cell response. To better understand the mechanisms involved in MPA activity we carried out cultures of splenocytes, bone marrow cells or lymph node cells from immunized mice in the presence of MPA, and evaluated the amount of antibody release to supernatants. We found that low doses of MPA (10−9 m and 10−10 m) significantly enhanced the in vitro production of specific immunoglobulin G (IgG) antibodies, an effect that appears to involve the interaction of the progestin with PRG receptors, as judged by the inhibition of MPA effects with ZK (10−8 m) or RU486 (10−9 m). These receptors were detected by flow cytometry analysis in a proportion of T lymphocytes. Because MPA did not increase the number of immunoglobulin‐secreting cells, our findings suggest that MPA enhanced the capacity of individual cells to produce specific immunoglobulin.
Inhibition of B16 melanoma experimental metastasis by interferon‐γ through direct inhibition of cell proliferation and activation of antitumour host mechanisms
Authors: Kakuta Shigeru , Tagawa Yoh‐ichi , Shibata Shinwa , Nanno Masanobu , Iwakura Yoichiro
Published: March 2003

Interferon‐γ (IFN‐γ) has pleiotropic activities other than its antivirus action, including cell growth inhibition, natural killer (NK) cell and cytotoxic T lymphocyte (CTL) activation, and angiogenesis inhibitory activity, and these activities are supposed to be involved in its antitumour activity. However, it has not been completely elucidated which activity is mainly involved in the tumour suppression in vivo. In this study, we analysed inhibitory mechanisms of endogenous IFN‐γ against B16 melanoma experimental metastasis. After intravenous injection of tumour cells, tumour deposits in the lungs and liver were increased and life span was shorter in IFN‐γ−/− mice, indicating important roles for IFN‐γ in antitumour mechanisms. Interestingly, tumour deposits were not increased in IFN‐γ receptor (R)−/− mice. Furthermore, only low levels of cell‐mediated immunity against the tumour and activation of NK cells were observed, indicating that antimetastatic effects of IFN‐γ is not mediated by host cells. The survival period of B16 melanoma‐bearing IFN‐γR−/− mice was, however, shorter than wild‐type mice. These observations suggest that IFN‐γ prevents B16 melanoma experimental metastasis by directly inhibiting the cell growth, although antitumour host functions may also be involved in a later phase.
Immunological characterization of a γδ T‐cell stimulatory ligand on autologous monocytes
Authors: Sathiyaseelan Thillainayagam , Naiman Brian , Welte Stefan , Machugh Niall , Black Samuel J. , Baldwin Cynthia L.
Published: March 2003

Bovine γδ T cells are stimulated to proliferate by autologous monocytes. This is referred to as the autologous mixed leucocyte reaction (AMLR). It has been shown previously that the stimulatory component is constitutively expressed on the monocyte plasma membrane and is a protein or has a protein moiety. Here we showed that γδ T‐cell responses to the monocytes requires interaction with the T‐cell receptor because Fab1 fragments of a monoclonal antibody (mAb) that reacts with the δ chain of the T‐cell receptor blocked proliferation in the AMLR. Monocyte molecules involved in stimulation were also characterized further by biochemical and immunological methods. A mAb, named M5, was generated by immunizing mice with bovine monocytes and shown to block the ability of monocytes to stimulate in the AMLR. Treatment of monocytes or monocyte membranes with high salt, chelating agents or phospholipase C did not affect their ability to stimulate γδ T‐cell proliferation or reactivity with mAb M5 indicating the ability of monocytes to stimulate does not involve peripheral membrane components or a glycosyl‐phosphatidylinsositol (GPI)‐anchored components. Hence it was concluded that the stimulation occurred as a result of intergral membrane proteins including that recognized by mAb M5. The ligand for mAb M5 was on all bovine monocytes and to a lower level on granulocytes but not on lymphocytes. MAb M5 also reacted with sheep monocytes but not with human monocytes or murine macrophages, in agreement with a previous reports that sheep monocytes but not human or mouse mononuclear phagocytes have the capacity to stimulate bovine γδ T cells in in vitro cultures. The level of expression of the M5 ligand was not altered by γ‐irradiation or culture of monocytes with lipopolysaccharide but it was decreased following culture with interferon‐γ‐containing cell culture supernatants.
Immunization onto bare skin with synthetic peptides: immunomodulation with a CpG‐containing oligodeoxynucleotide and effective priming of influenza virus‐specific CD4+ T cells
Authors: Beignon Anne‐Sophie , Briand Jean‐Paul , Muller Sylviane , Partidos Charalambos D.
Published: March 2003

Exploiting the immune system of the skin for vaccine administration offers an attractive alternative to the currently used invasive immunization procedures. In this study we report that a synthetic peptide representing a T‐helper (Th) epitope from influenza virus haemagglutinin (aa 307–319) can be an effective immunogen when coapplied with cholera toxin (CT) onto bare skin. Proliferation of both peptide‐ and influenza virus‐specific CD4+ T cells was measured in lymphocyte cultures from spleens and regional lymph nodes. The presence of the CpG oligodeoxynucleotide 1826 in the peptide/CT formulation, enhanced the proliferation of peptide‐ and virus‐specific T cells as measured by the conventional [3H]thymidine uptake and interleukin (IL)‐2 assays. Furthermore, the bias towards Th2‐type of responses stimulated by CT was shifted towards Th1 as demonstrated (i) by the increase of interferon‐γ and decrease of IL‐4 cytokine levels measured in culture supernatants, (ii) by the predominance of IG2a anti‐CT antibodies in the serum, and (iii) by the down‐regulation of total serum IgE antibody levels. These findings demonstrate the potential of the bare skin as a non‐invasive route for administration of small molecular size peptide antigens. Furthermore, with the selection and combination of the appropriate type of adjuvants, immune responses can be modulated towards the desired type of Th phenotype.
Association of the absence of palmaris longus tendon with an anomalous superficial palmar arch in the human hand
Authors: O'Sullivan Elizabeth , Mitchell Barry S
Published: March 2003

The normal arterial supply to the human hand is via the ulnar and radial arteries which unite mid‐palm to form a complete arch called the superficial palmar arch (SPA). From the SPA blood vessels pass anteriorly to supply the thumb and digits, and deeply to complete the deep palmar arch. Previous reports have documented anomalies of the SPA formation, and this may change the normal blood distribution to the thumb and the digits. There have also been reports of the absence of the palmaris longus tendon. A total of 47 embalmed cadaveric hands (some paired, some single) were dissected and the presence of an anomalous SPA was more frequently observed when the palmaris longus tendon was absent. This may be significant when considering the suitability of patients for hand surgery which involves interruption to the vascular supply to the hand, e.g. harvesting upper limb vessels for coronary artery grafting. The current techniques for assessing the vascular supply to the hand (Allens test and/or Doppler ultrasounding) are unreliable. Demonstration of a palmaris longus tendon in the living arm is easy and the use of this in combination with the other techniques may improve overall reliability.
Demographic dynamics of a neotropical small rodent (Phyllotis darwini): feedback structure, predation and climatic factors
Authors: Lima Mauricio , Julliard Romain , Stenseth Nils CHR. , Jaksic Fabian M.
Published: March 2003

The leaf‐eared mouse (Phyllotis darwini) exhibits large numerical fluctuations associated with high‐ and low‐rainfall years in semi‐arid Chile. Using capture–mark–recapture (CMR) statistical modelling, we provide a detailed description of the demographic variation in this species. We studied between‐year and seasonal variation of demography, and tested for the relative importance of endogenous and exogenous factors as covariates of survival, recruitment, maturation and reproduction over a 12‐year period.

 The demographic variables studied show larger between‐year than within‐year (seasonal) variation, emphasizing the importance of this source of external variability. We found that both feedback structure and exogenous factors operate together on different demographic processes of this species.

 We found positive direct feedback effects on survival rate and negative feedback on recruitment, fraction of reproductive individuals and female maturation rates. The ratio between barn and magellanic horned owls showed an important effect on most of the demographic variables of leaf‐eared mice, in particular by influencing negatively survival rates and the fraction of reproductive individuals, thus suggesting the importance of non‐lethal predation.

 Hence, feedback intrinsic mechanisms (density‐dependence), owls and climate (rainfall and Southern Oscillation Index (SOI)) operate simultaneously in determining the demography of leaf‐eared mice. We hypothesize that trophic interactions with owls (and perhaps other predators) may cause second‐order feedback responses in demography and population dynamics of this small rodent species.
Delayed cost of reproduction and senescence in the willow tit Parus montanus
Authors: Orell Markku , Belda Eduardo J.
Published: March 2003

We studied age‐specific survival rates in the willow tit Parus montanus in northern Finland using 15 years of capture–recapture data obtained from birds during the breeding seasons 1986–2000. In addition, short‐ and long‐term costs of reproduction were investigated by comparing survival probabilities of breeding and non‐breeding individuals.

We did not find evidence supporting age‐specific survival probabilities in males. However, in females there was a significant decline in survival after the age of 5 years.

Reproduction did not impair individuals’ chances of being alive in the subsequent year (short‐term cost) because breeding males and females had similar survival rates as non‐breeders.

Demographic costs of breeding appeared later in life. Females skipping breeding earlier in life showed a higher probability of survival after the age of 5 years than females that bred every year until that age. This effect was non‐significant in males.

The observed decline in survival probability late in life is likely to result from an increased cost of reproduction due to higher allocation of resources to breeding earlier in life, i.e. increased effort early in life is traded with survival late in life. The results also suggest that income breeders, such as small passerines, may pay long‐term costs of reproduction. This is in agreement with the disposable soma theory of ageing.
Diagnosing the cause of population changes: localized habitat change and the decline of the endangered St Helena wirebird
Authors: McCulloch Neil , Norris Ken
Published: March 2003

Statistical models of population density and/or change in relation to habitat could aid the management of endangered species and help diagnose causes of population decline. Such models seek ‘global’ explanations for any decline, but endangered species are often vulnerable to highly localized habitat change that can have a significant impact on overall population. In such cases, statistical models can aid in interpreting the impact of localized habitat change on population density and so have a role in diagnosis. We illustrate this approach using data from the endangered St Helena wirebird, a small sand plover endemic to the island of St Helena in the South Atlantic Ocean.

 The wirebird inhabits pasture habitats and semi‐desert areas. Census data suggest that wirebird abundance declined during the early 1990s, from 425 adult birds in 1989 to 335 adult birds by 1998–99. Abundance declined by 34·4% in pasture habitats, whereas abundance in semi‐desert increased by 18% over this period.

We tested the hypothesis that the decline in abundance in pasture habitats was driven by vegetation change. Multiple regression modelling revealed that wirebird density in pasture was positively correlated with the cover of broad‐leaved herbs, but negatively correlated with vegetation height and gorse cover prior to the decline in 1989. A performance test of this model showed that predictions were reliable.

The cover of broad‐leaved herbs declined significantly between 1989 and 1998–99. However, there was no correlation between the change in wirebird density and the change in broad‐leaved herb cover, indicating that this vegetation change was unlikely to have caused the decline in wirebird abundance.

The decline in the abundance of wirebirds in pasture habitats was primarily due to changes in three sites. Each experienced site‐specific habitat changes, which were likely to cause a decrease in wirebird abundance on the basis of the multiple regression modelling of wirebird density in relation to habitat. We concluded that highly localized vegetation change, rather than general herb cover, played an important role in the overall population decline.

Our analysis provides clear habitat management recommendations: pasture management for livestock needs to be compatible with the production of herb‐rich grassland, consisting of short vegetation and few woody plants, in order to benefit wirebird conservation.

 Management decisions for endangered species are often required urgently, and as a result are invariably based on incomplete information, particularly concerning the demographic mechanisms involved in decline. Our approach illustrates a role for simple statistical models under these circumstances. Such models help diagnose the cause of a decline and promote initial, remedial, management actions. This work also shows how habitat effects on endangered species can be highly localized.
Differential facilitation by a nitrogen‐fixing shrub during primary succession influences relative performance of canopy tree species
Authors: Bellingham P. J. , Walker L. R. , Wardle D. A.
Published: March 2003

The facilitative and inhibitory effects of a nitrogen‐fixing shrub, Carmichaelia odorata, during primary succession were studied using both field measurements in a New Zealand temperate montane valley, and manipulative glasshouse experiments on seedlings of the three dominant tree species, Griselinia littoralis, Metrosideros umbellata and Weinmannia racemosa.

During a stand development chronosequence of < 100 years in which Carmichaelia colonized, dominated and senesced, there was significant development of soil organic horizons and a large build‐up of soil nitrogen, especially in the organic horizon. Soil organic matter and nitrogen levels across the sequence were strongly correlated with the main DCA axis of vascular plant species composition, along which there was change in dominance from herbaceous to woody species. Vegetation increased in height and light levels declined with stand development.

Similar responses to shade that mimicked that in mature Carmichaelia stands suggested that inhibitory effects were likely to be uniform across the three tree species.

Nitrogen, either added via Carmichaelia litter or in solution, enhanced shoot biomass and foliar nitrogen concentrations of all three tree species. Growth in soils of increasing development increased foliar nitrogen concentrations for Griselinia and Weinmannia, but not Metrosideros.

Overall, Metrosideros was the least responsive to potential facilitative effects of Carmichaelia, and Griselinia exhibited the highest degree of plasticity of response. Future forest composition and spatial patterning of species in mixed stands here, as elsewhere, is likely to result from differential facilitative responses during early primary succession.
Bone morphogenetic protein‐7 stimulates initial dendritic  growth in sympathetic neurons through an intracellular  fibroblast growth factor signaling pathway
Authors: Horbinski C. , Stachowiak E. K. , Chandrasekaran V. , Miuzukoshi E. , Higgins D. , Stachowiak M. K.
Published: March 2003

Bone morphogenetic protein‐7 (BMP‐7), a member of the transforming growth factor (TGF)‐β superfamily of signaling cytokines, induces dendritic growth in rat sympathetic neurons. In this study, we present evidence that the recently discovered integrative nuclear FGFR1 signaling (INFS) pathway is involved in dendrite outgrowth mediated by BMP‐7. Immunocytochemical analysis of expressed fibroblast growth factors (FGFs) showed that little FGF‐2 was detected in control neurons, but the expression of this molecule in the cytoplasm and nucleus increased within 6 h after BMP‐7 treatment. In contrast, FGF‐1 was constitutively present in the peripheral cytoplasm and in neurites under control conditions, and its distribution did not change with BMP‐7 exposure. The high‐affinity receptor FGFR1 was present in low amounts in control neurons and was associated with the cytoplasm, the plasma membrane, and the nucleus. Twenty‐four hours of␣BMP‐7 treatment elicited an increase in FGFR1 nuclear localization. Overexpressed constructs of FGFR1 that lack the␣tyrosine kinase domain, and have been shown to act in a␣dominant‐negative manner on FGFR1 signaling, inhibited BMP‐7 mediated initial dendrite outgrowth in transfected neurons by ≈ 50%. However, targeted inhibition of extracellular FGF‐2 by overexpression of a secreted receptor mutant FGFR1(TM–) lacking the transmembrane domain failed to affect BMP‐7 induced dendritic growth, as did treatment with the extracellular FGFR antagonist inositol hexakisphosphate. These results suggest that the INFS, which has already been␣implicated in a broad range of activities in other cell types, may also be required for BMP‐7 to stimulate dendritic development.
Na+/H+ exchange subtype 1 inhibition during extracellular acidification and hypoxia in glioma cells
Authors: Glunde Kristine , Düßmann Heiko , Juretschke Hans‐Paul , Leibfritz Dieter
Published: March 2003

Lactacidosis is a common feature of ischaemic brain tissue, but its role in ischaemic neuropathology is still not fully understood. Na+/H+ exchange, a mechanism involved in the regulation of intracellular pH (pHi), is activated by low pHi. The role of Na+/H+ exchange subtype 1 was investigated during extracellular acidification and subsequent pH recovery in the absence and presence of (4‐isopropyl‐3‐methylsulphonyl‐benzoyl)‐guanidine methanesulfonate (HOE642, Cariporid), a new selective and powerful inhibitor of the Na+/H+ exchanger subtype 1 (NHE‐1). It was compared for normoxia and hypoxia in two glioma cell lines (C6 and F98). pHi was monitored by fluorescence spectroscopy using the intracellularly␣trapped␣pH‐sensitive dye 2′,7′‐bis(carboxyethyl)‐5(6)‐carboxyfluorescein (BCECF). Alterations in glial cell metabolism were characterized using high‐resolution 1H, 13C and 31P NMR spectroscopy of perchloric acid extracts. NHE‐1 contributed to glial pH regulation, especially at pathologically low pHi values. NHE‐1 inhibition with HOE642 during acidification caused exacerbated metabolic disorders which were prolonged during extracellular pH recovery. However, NHE‐1 inhibition during hypoxia protected the energy state of glial cells.
Locally synthesized angiotensin modulates pineal melatonin generation
Authors: Baltatu Ovidiu , Afeche Solange Castro , Santos Sabrina Heloísa José dos , Campos Luciana Aparecida , Barbosa Roseli , Michelini Lisete C. , Bader Michael , Cipolla‐Neto José
Published: March 2003

Abstract+

We aimed to study the mechanisms and the significance of the influence exerted by the renin‐angiotensin system (RAS) on the pineal melatonin production. Pineal melatonin and other indoles were determined by HPLC with electrochemical detection after angiotensin AT1‐receptor blockade with Losartan in vivo or in cultured glands. N‐acetyltransferase (NAT) activity was radiometricaly measured. To test the in vivo relevance of the local RAS, pineal melatonin and its indole precursors were determined in transgenic rats with inhibited production of angiotensinogen exclusively in astrocytes, TGR(ASrAOGEN). Tryptophan hydroxylase (TPH) and NAT mRNA levels were determined by real‐time RT–PCR. Pineal melatonin content was significantly decreased by AT1‐receptor blockade in vivo, in cultured glands and in TGR(ASrAOGEN) (35%, 32.4% and 17.5% from control, respectively). Losartan produced a significant decrease of pineal 5‐hydroxytryptophan, serotonin, 5‐hydroxyindole acetic acid and N‐acetylserotonin in pineal cultures. Also, the pineal content of the precursor indoles in TGR(ASrAOGEN) rats was significantly lowered. The reduction of 5‐hydroxytryptophan levels by 33–75% in both in vivo and in vitro studies suggests a decreased activity of TPH. Moreover, the TPH mRNA levels in TGR(ASrAOGEN) rats were significantly lower than control rats. On the other hand, NAT activity was unaffected by Losartan in pineal culture and its expression was not significantly different from control in TGR(ASrAOGEN) rats. Our results demonstrate that a local pineal RAS exerts a tonic modulation of indole synthesis by influencing the activity of TPH via AT1‐receptors.
Geldanamycin specifically modulates thrombin‐mediated morphological changes in mouse neuroblasts
Authors: Pai Karnire Sadashiva , Cunningham Dennis D.
Published: March 2003

Regulation of neuronal morphology and extension of cell processes are required for normal synaptic connections and signaling. Thrombin, a serine protease, regulates neuronal morphological changes by activating protease activated receptor‐1 (PAR‐1), a seven‐transmembrane G protein‐coupled receptor. Thrombin‐mediated morphological changes precede its diverse action on neurons, and the drugs that regulate these morphological changes have important therapeutic implications. The present study was carried out to evaluate the role of geldanamycin, a specific inhibitor of Hsp90 on thrombin‐induced regulation of neuronal morphology. Incubation of mouse neuroblasts (NB2a) with geldanamycin prevented thrombin‐mediated neurite retraction in a dose‐dependent manner. Geldanamycin also blocked thrombin‐induced activation of RhoA, a small GTP binding protein involved in the cytoskeletal signaling. To determine the specificity of geldanamycin action, its effect on lysophosphatidic acid (LPA)‐induced morphological changes was examined. Geldanamycin did not have any effect on LPA‐induced neurite retraction and RhoA activation indicating a specific role for this drug in the regulation of thrombin‐mediated morphological changes.