bluuebunny/crossref_metadata_2025 huggingface dataset:
Crayfish in lakes and streams: individual and population responses to predation, productivity and substratum availability
Authors: NYSTRÖM PER , STENROTH PATRIK , HOLMQVIST NIKLAS , BERGLUND OLOF , LARSSON PER , GRANÉLI WILHELM
Published: September 2006

1. In a correlative study, we investigated the relative importance of fish predation, refuge availability and resource supply in determining the abundance and size distributions of the introduced and omnivorous signal crayfish (Pacifastacus leniusculus) in lakes and streams. Moreover, the biomass and food selection of predatory fish was estimated in each habitat type and stable isotopes of carbon and nitrogen were measured in perch (Perca fluviatilis), the dominant predator in the lakes, and in its potential food sources (crayfish, juvenile roach and isopods).

2. In lakes, crayfish were the most frequent prey in large perch (46%), followed by other macroinvertebrates (26%, including the isopod Asellus aquaticus) and small fish (25%). Crayfish and fish dominated the gut contents of large perch with respect to biomass. Nitrogen signatures showed that perch were one trophic level above crayfish (approx. 3.4‰) and a two‐source mixing model using nitrogen isotope values indicated that crayfish (81%) contributed significantly more to perch isotope values than did juvenile roach (19%). A positive correlation was found between the abundance of crayfish and the biomass of large perch. Crayfish abundance in lakes was also positively correlated with the proportion of cobbles in the littoral zone. Lake productivity (chlorophyll a) was positively correlated with crayfish size, but not with crayfish abundance.

3. In streams, brown trout (Salmo trutta) were the most abundant predatory fish. Gut contents of large trout in a forested stream showed that terrestrial insects were the most frequently found prey (60%), followed by small crayfish (27%) and isopods (27%). In contrast to lakes, the relative abundance of crayfish was negatively correlated with the total biomass of predatory fish and with total biomass of trout. However, abundance of crayfish at sites with a low biomass of predatory fish varied considerably and was related to substratum grain size, with fewer crayfish being caught when the substratum was sandy or dominated by large boulders. The mean size of crayfish was greater at stream sites with a high standing stock of periphyton, but neither predator biomass nor substratum grain size was correlated with crayfish size.

4. Our results suggest that bottom‐up processes influence crayfish size in lakes and streams independent of predator biomass and substratum availability. However, bottom‐up processes do not influence crayfish abundance. Instead, substratum availability (lakes) and interactions between predation and substratum grain size (streams) need to be considered in order to predict crayfish abundance.
Mash1 promotes neuronal differentiation in the retina
Authors: Tomita Koichi , Nakanishi Shigetada , Guillemot Franqois , Kageyama Ryoichiro , Nishikawa Shin‐ichi
Published: September 2006

Background: Mash1, a mammalian homologue of Drosophila achaete‐scute proneural gene complex, plays an essential role in differentiation of subsets of peripheral neurones. Whereas Mash1 is expressed during retinal development, no apparent abnormalities were found during embryogenesis as well as at birth in Mash1‐null retina, suggesting that early differentiating cells such as ganglion, amacrine and cone cells develop normally. Because Mash1‐null mice die soon after birth, their postnatal development cannot be examined in vivo. Thus, it remains to be determined whether or not Mash1 functions in postnatal development of retina.

Results: Here, Mash1 roles in postnatal development of retina was examined by using retinal explant that develops like in vivo retina. Without Mash1, differentiation of late appearing cells such as rod, horizontal, and bipolar cells was delayed and the final number of bipolar cells was significantly reduced. In contrast, vimentin‐positive cells (probably Müller glial cells) were increased in Mash1‐null retina.

Conclusions: These results provide evidence that Mash1 promotes neuronal differentiation during retinal development and is essential for proper ratios of retinal cell types.
The Escherichia coli chromosome is organized with the left and right chromosome arms in separate cell halves
Authors: Nielsen Henrik J. , Ottesen Jesper R. , Youngren Brenda , Austin Stuart J. , Hansen Flemming G.
Published: September 2006

We have developed a system for the simultaneous labelling of two specific chromosomal sites using two different fluorescent ParB/parS systems. Using this, we demonstrate that the two chromosome arms are spatially arranged in newborn cells such that markers on the left arm of the chromosome lie in one half of the cell and markers on the right arm of the chromosome lie in the opposite half. This is achieved by reorganizing the chromosome arms of the two nucleoids in pre‐division cells relative to the cell quarters. The spatial reorganization of the chromosome arms ensures that the two replication forks remain in opposite halves of the cell during replication. The relative orientation of the two reorganized nucleoids in pre‐division cells is not random. Approximately 80% of dividing cells have their nucleoids oriented in a tandem configuration.
Cell‐mediated cytotoxicity is the main innate immune mechanism involved in the cellular defence of gilthead seabream (Teleostei: Sparidae) against Enteromyxum leei (Myxozoa)
Authors: CUESTA A. , SALINAS I. , RODRÍGUEZ A. , MUÑOZ P. , SITJÀ‐BOBADILLA A. , ÁLVAREZ‐PELLITERO P. , MESEGUER J. , ESTEBAN M. Á.
Published: September 2006

The cellular innate immune response of gilthead seabream (Sparus aurata L.) against the myxozoan Enteromyxum leei was studied. Enteromyxosis was transmitted by maintaining uninfected fish (recipients) together with infected animals. A group of fish not exposed to the infection served as controls. After 10, 22, 38, 52 and 108 days, control and recipient fish were sampled and leucocyte subpopulations and cellular immune responses (leucocyte peroxidases, phagocytosis, respiratory burst and cytotoxicity) of the head‐kidney leucocytes were determined. The percentage of acidophilic granulocytes was significantly lower in non‐parasitized and parasitized recipient fish than in control fish after 22 days but no significant differences were seen between non‐parasitized and parasitized recipient animals. The leucocyte peroxidase content, phagocytosis and respiratory burst activity were seen to have decreased significantly at different sampling times in both non‐parasitized and parasitized recipient fish with respect to the controls, whereas cytotoxic activity was up to 2·3 times higher than in control fish. Within the recipient group, little difference was observed in the studied parameters between non‐parasitized and parasitized fish. These data demonstrate that cytotoxic activity may have an important role in the defence of gilthead seabream against the myxosporean E. leei. Immunological implications of E. leei infections are discussed.
Gonadectomy and progesterone treatment induce protection in murine cysticercosis
Authors: VARGAS‐VILLAVICENCIO J. A. , LARRALDE C. , MORALES‐MONTOR J.
Published: September 2006

The effects of progesterone on castrated mice of both sexes infected with Taenia crassiceps cysticerci were studied. Gonadectomy and treatment with progesterone before infection decreased parasite loads by 100% compared with intact uninfected mice. mRNA levels of IFN‐γ and IL‐2 (typically associated to Th1‐like profiles) were markedly decreased in infected gonadectomized (Gx) mice, whereas progesterone treatment of infected Gx mice did not affected its expression. mRNA levels of IL‐4, and IL‐10 (typically associated with Th2‐like profiles) were reduced by gonadectomy, whereas restitution with progesterone did not affected this pattern in infected Gx progesterone‐treated mice. Infection markedly induced expression of progesterone receptor isoform A in splenocytes of Gx mice (5‐fold), whereas isoform B had no changes. Progesterone metabolism to dehydroepiandrosterone (DHEA) in Gx animals was increased 3‐fold only in infected progesterone‐treated uninfecteds of both sexes, but was not detectable in infected Gx progesterone‐treated mice. Conversely, DHEA levels increased 100‐fold in infected Gx progesterone‐treated mice. However, androgen receptor expression in splenocytes of male mice showed a reduction by gonadectomy, and by infection, whereas in females AR expression showed no changes in the different mouse groups. These results suggest that progesterone, through its metabolism to DHEA, negatively affects the establishment, growth, and reproduction of Taenia crassiceps, by a mechanism that does not implicate a classic genomic pathway involving a nuclear androgen receptor.
Expulsion of the gastrointestinal cestode, Hymenolepis diminuta by tolerant rats: evidence for mediation by a Th2 type immune enhanced goblet cell hyperplasia, increased mucin production and secretion
Authors: WEBB R. A. , HOQUE T. , DIMAS S.
Published: September 2006

The processes underlying expulsion of Hymenolepis diminuta in rats are not known. Expression levels of mRNAs of several cytokines revealed a Th2 response that differed between worm infection levels. IL‐4 protein levels decreased while IL‐13 levels increased in a 50‐worm infection by 30 dpi; the converse was seen with a five‐worm infection. A negative correlation was found between IL‐4 or IL‐13 mRNA expression and worm biomass, between IL‐13 protein levels and worm number or worm biomass, and between IL‐4 protein levels and worm biomass in 50‐worm infections. A negative correlation between IL‐4 mRNA or protein expression and worm biomass was observed with five‐worm infections. A strong correlation between Muc2 mRNA expression and decreased worm number or biomass in a 50‐worm infection was observed. Muc2 protein, goblet cell numbers and mucin decreased in a 50‐worm infection by 20 days post‐infection. These changes were not seen with five‐worm infections where worms are not expelled. The data show that rats infected with 50 H. diminuta mount a Th2 response leading to high levels of IL‐13, increased goblet cell numbers and increased mucin2 production and release. The mucus traps the worms, which are progressively expelled from the small intestine.
Molecular diagnostic key for identification of single juveniles of seven common and economically important species of root‐knot nematode (Meloidogyne spp.)
Authors: Adam M. A. M. , Phillips M. S. , Blok V. C.
Published: September 2006

A molecular protocol is presented for distinguishing seven of the most common and economically important Meloidogyne spp. DNA was extracted from individual second‐stage juvenile (J2) nematodes of Meloidogyne spp. and amplified by PCR (polymerase chain reaction). Fifteen PCRs including amplification of rDNA, specific SCAR (sequence characterized amplified region) and RAPD (random amplified polymorphic DNA) fragments were possible from the extracted DNA. This enabled a molecular diagnostic key for M. incognita, M. javanica, M. arenaria, M. mayaguensis, M. hapla, M. chitwoodi and M. fallax to be designed. The key unifies published methods into a single logical schematic using primer combinations that were previously validated and shown to work reliably and specifically. The protocol can be used with single juvenile or adult nematodes and the schematic can readily be expanded to accommodate more species. The use of RAPD amplification to assist with identification of samples which do not yield diagnostic amplification products after the first three steps of the molecular key is also described.
Oligoclonal Macroglobulinaemia
Authors: HARBOE M. , HANNESTAD K. , SLETTEN K.
Published: September 2006

Ninety macroglobulinaemia sera were tested for occurrence of multiple monoclonal immunoglobulins. Thirteen (14%) of the sera contained more than one monoclonal immunoglobulin. The homogeneous macroglobulins were isolated from 3 sera; in each case individually specific antigenic determinants common to the two components were demonstrated, in addition to determinants unique for each component. NH2‐terminal amino acid sequence studies in two patients showed that the IgM heterogeneity was due to differences in the primary structure of the variable parts of the μ (case Tö) and the μ (case æ) chains. Macroglobulinaemia appears to be a unique source of homogeneous immunoglobulins from related clones.
Immunoglobulin Receptors on Mouse Mast Cells
Authors: WARNER N. L. , OVARY Z.
Published: September 2006

Interaction of mouse immunoglobulins with a mast cell tumor HC was studied by the rosette technique. All mast cells formed rosettes, and this could be inhibited by IgG1 myeloma proteins, less efficiently by IgG2, and not by IgA or IgM. Antigen antibody complexes formed under appropriate con ditions also inhibit, with at least 100‐fold greater efficiency than free im munoglobulin. Antisera containing reaginic activity also inhibit rosettes in the presence of antigen, but on heating the sera, a concomitant loss of reaginic activity and rosette inhibition occurs. It is proposed that there is a specific receptor on the mast cell surface for IgG1 and reaginic immunoglobulins, and that binding to this site in the form of a complex of correct antigen ratio, will initiate the anaphylactic process.
In Vitro Target Cell Lysis Mediated by Normal Human Lymphocytes (K Cells) or Monocytes
Authors: LARSSON A. , ÖHLANDER C.
Published: September 2006

Guinea pig IgGl or IgG2 anti‐dinitrophenyl (DNP) antibody preparations were used for induction of target cell lysis by normal human lymphocytes (K cells) or monocytes. Target cells were DNP‐coated 51Cr‐labeled chicken erythrocytes. Antibody concentrations were assayed by an ammonium sulphate precipitation technique. When antiserum was obtained by immunization with the antigen in Freund's complete adjuvant (FCA), IgG2 antibodies predominated and were significantly more efficient inducers of K‐cell‐mediated lysis than IgGl antibodies. The lowest activity in K‐cell‐mediated lysis was seen with IgGl from antiserum obtained by immunization with antigen in Freund's incomplete adjuvant. When these antibody fractions were tested in monocyte‐mediated erythrolysis, the two IgGl fractions were as active as the IgG2 antibodies raised with antigen incorporated in FCA. The results suggest that the Fc receptors of mature human blood monocytes are different from those on the effector cells in the K‐cell preparations.
Evidence of Different Cell Populations in the Mouse Thymus Releasing and Responding to Mitogenic Factor
Authors: JACOBSSON H. , BLOMGREN H.
Published: September 2006

The thymocyte population of mice treated with cortisone was examined at various times with respect to its relative capacity to be triggered to DNA synthesis by soluble phytomitogens or mitogenic factors (MF) released by lymph node cells exposed to phytomitogens. The capacity of the thymocyte population to produce MF in response to phytomitogen exposure was also examined. We found that the relative blastogenic activity of both phytomitogens and MF on thymocytes increased as the cell number of the thymus was reduced by the cortisone treatment. However, the reactivity to phytomitogens increased to a higher extent. During the subsequent regeneration of the organ the stimulability of the cells by phytomitogen decreased far below that of MF. The relative capacity of thymocytes to produce MF seemed to parallel their phytomitogen reactivities Onepossible explanation of the results is that there exists one subpopulation of cells in the thymus more responsive to phytomitogens than to MF and another more responsive to MF than to phytomitogen. It is possible that the cells that are phytomitogen‐responsive are those that can produce MF.
An Experimental Model in Mink for Studying the Relation Between Amyloid Fibril Protein AA and the Related Serum Protein, SAA
Authors: HUSBY G. , NATVIG J. B. , SLETTEN K. , NORDSTOGA K. , ANDERS R. F.
Published: September 2006

Experimental amyloidosis was induced in mink by repeated injections with endotoxin. Amyloid fibrils extracted from liver and spleen were fractionated by gel filtration after treatment with guanidine‐hydrochloride and a reducing agent, dithiothreitol. An elution profile very similar to that of human amyloid fibrils, having protein AA as a major component, was obtained. The mink amyloid protein eluted at a position similar to that of human protein AA was by amino acid composition and partial sequence studies shown to be very similar to the latter protein and was called mink protein AA. In addition, a protein AA‐related component (protein SAA) was found in increased amounts in serum of amyloidotic mink, providing further evidence of the homology with human amyloidosis. Experimental amyloidosis in mink represents a suitable model for studying amyloid proteins and related serum components.
Elution and Characterization of Lymphocytes from Rheumatoid Inflammatory Tissue
Authors: ABRAHAMSEN T. G. , FRØLAND S. S. , NATVIG J. B. , PAHLE J.
Published: September 2006

Lymphocytes were eluted from the synovial tissue of 19 patients with classical rheumatoid arthritis. The tissue was minced and dissociated by treatment with crude collagenase and DNase. The cell suspension obtained was filtered and incubated in plastic culture flasks overnight at 37°C. The cells that did not adhere to the plastic surface were harvested and the lymphocytes further purified by the Ficoll‐Isopaque gradient centrifugation technique. The lymphocyte yield varied from 0.64 to 32 × 106 cells. Differential counts showed on the average 85% lymphocytes, 12% macrophage‐like cells, and variable proportions of polymorphonuclear granulocytes, unclassified cells, and dead cells. An average of 77% of the cells were viable as assessed by the trypan blue exclusion test. This cell suspension was investigated for lymphocyte populations. T lymphocytes were predominant in all experiments (mean, 73–6%). The mean percentage of B lymphocytes was 9.7%, whereas the proportion of Fc‐receptor‐bearing lymphocytes was on the average 6.0%.
Selective Enhancement of Leu Cam Expression by Interleukin 6 during Differentiation of Human Promonocytic U937 Cells
Authors: DUITS A. J. , JAINANDUNSING S. M. , VAN DE WINKEL J. G. J. , CAPEL P. J. A.
Published: September 2006

Interleukin 6 (IL‐6) is a cytokine with multiple biological activities on various tissues and cells. We have investigated the effect of recombinant human IL‐6 (rhlL‐6) on growth and differentiation of U937. Recombinant human IL‐6 induced a dose‐dependent growth inhibition, apparent around day 4, of up to 50% by day 8 of culture. Concomitant with this, changes in cytochemical activities were observed, indicative or differentiation. A panel of U937 antigens was analysed after culture with rhIL‐6. Expression of the majority of these membrane antigens was unaffected, with the exception of two classes. First, rhIL‐6 had a profound effect on members of the leucocytic cell adhesion molecules (Leu‐CAM) family. Expression of the α‐chain of CR3 (complement receptor 3; CD11b) was enhanced in a dose‐dependent fashion, with maximal expression around day 7. Parallel to this a simultaneous increase in β‐chain (CD18) expression was found. Furthermore, enhanced expression of CR3 was, accompanied by increased rosetting with sheep erythrocytes sensitized with C3bi. A much lower, but significant, enhancement was observed for the α‐chain of the p150,95 antigen (CD11c). Expression of leucocyte function‐associated antigen‐1, (LFA‐1), (CD11a/CD18) remained unchanged. Remarkably, however, expression of a ligand of LFA‐1, intercellular adhesion molecule‐1 (ICAM‐1; CD54), was enhanced with similar kinetics as CR3 and p150,95. A specific anti‐rhlL‐6 antiserum completely inhibited the IL‐6 effect. These observations provide further support for an important role of IL‐6 in the regulation of myeloid cell development in man.
Activation of Human T Lymphocytes by Leishmania Lipophosphoglycan
Authors: KEMP M. , THEANDER T. G. , HANDMAN E. , HEY A. S. , KURTZHALS J. A. L. , HVIID L. , SØRENSEN A. L. , WERE J. O. B. , KOECH D. K. , KHARAZMI A.
Published: September 2006

This study describes Leishmania antigen‐induced activation of lymphocytes isolated from Kenyan donors, previously treated for visceral leishmaniasis. and from Danish and Kenyan controls. Peripheral blood mononuclear cells (PBMC) from cured Kala‐Azar patients proliferated and produced Interferon‐γ in vitro in response lo lipophosphoglycan (LPG) isolated from Leishmania major. The proliferative response was mainly due lo activation of Cn2‐posilive T cells, PBMC from controls did not respond to LPG. hut to sonicates prepared from both L. major and L. donovani promastigotes. The surface glycoprotein GP 63 failed lo activate PBMC from any of the donors tested.

These results show that the individuals cured from visceral leishmaniasis had expanded T‐cell clones recognizing LPG. conceivably as a result of Leishmania infection. The LPG preparation was without detectable protein contamination. Thus, the results suggest that human T lymphocytes can respond to glycolipid antigens.
Diagnosis of acute foetal distress does not preclude banking of umbilical cord blood units
Authors: Picardi A. , Tamburini A. , Caravita T. , De Angelis C. , Ballatore G. , Spagnoli A. , Malerba C. , Calugi A. , De Fabritiis P. , Amadori S.
Published: September 2006

summary Clinical diagnosis of acute foetal distress (AFD) is based on several parameters such as abnormal foetal heart rate (FHR) pattern and/or meconium liquid staining (MLS). Standards for cord blood (CB) banking indicate that AFD should be considered as exclusion criteria for CB collection, but precise guidelines on how to proceed with CB collection in the presence of AFD signs during labour are not available. We evaluated whether the presence of FHR abnormality and/or MLS during labour 1) reduced the CB collection activity; 2) were associated with the infant’s acidaemia or asphyxia and 3) deteriorated the biological characteristics of CB units. Thirty‐three units of CB were evaluated for biological parameters, gas values and newborn’s Apgar score. The results were compared with a control group of 33 consecutive units previously banked. No differences were observed between the two groups and all but one newborn showed normal Apgar score and absence of metabolic acidaemia. The results showed that 1) AFD reduced the CB collection activity by 10% each year; 2) the majority of CB units collected in the presence of abnormal FHR and/or meconium have biological characteristics eligible for banking; 3) FHR alterations or meconium in the presence of normal gas analysis do not represent certain diagnosis of AFD.
Perioperative intravenous iron preserves iron stores and may hasten the recovery from post‐operative anaemia after knee replacement surgery
Authors: García‐Erce J. A. , Cuenca J. , Martínez F. , Cardona R. , Pérez‐Serrano L. , Muñoz M.
Published: September 2006

summary In unilateral total knee replacement (TKR), perioperative blood loss, low transfusion thresholds and short hospital stay result in patients being discharged with low haemoglobin (Hb). We assessed the effects of perioperative administration of intravenous iron, with or without erythropoietin, plus a restrictive transfusion threshold (Hb < 80 g L−1) both on transfusion rate and recovery from post‐operative anaemia.

TRK patients received iron sucrose (2 × 200 mg per 48 h, iv) (Group IVI, n = 129). Patients with admission Hb < 130 g L−1, also received erythropoietin (1 × 40 000 IU, sc) (Group EPO, n = 19). Perioperative clinical and laboratory data were obtained.

Mean Hb loss was 36 g L−1, but only seven patients were transfused (5%). Pre‐operatively, 66 (45%) patients did not have enough stored iron to compensate Hb loss. At post‐operative day 30, only 15% were anaemic, 70% of Hb loss and 92% of pre‐operative Hb were recovered and ferritin increased by 73 μg L−1 (P < 0·01), although erythropoietic response was higher in patients receiving erythropoietin (P < 0·05). No adverse effects of iron sucrose or erythropoietin were witnessed.

This protocol seems to reduce allogeneic blood transfusion rate and may hasten the recovery from post‐operative anaemia in TKR patients, without depleting iron stores. Further studies are needed to ascertain which patients may benefit of extended intravenous iron and/or erythropoietin administration.
Malaria control using indoor residual spraying and larvivorous fish: a case study in Betul, central India
Authors: Singh Neeru , Shukla M. M. , Mishra A. K. , Singh M. P. , Paliwal J. C. , Dash A. P.
Published: September 2006

Objectives  To assess the impact of intensified malaria control interventions in an ethnic minority community in Betul using existing tools.

Methods  Two rounds of indoor residual spraying with synthetic pyrethroid insecticide were applied and larvivorous fish introduced, followed by intensive surveillance for early detection of Plasmodium falciparum with rapid diagnostic tests and prompt treatment with sulphadoxine pyrimethamine.

Results  Pre‐intervention surveys revealed a very high fever rate in the community in all age groups with a slide positivity rate of >50% with >90%P. falciparum. The post‐intervention phase showed a sharp steady decline in number of malaria cases (β 0.972; P < 0.0001, 95% CI 0.35–0.47). Monitoring of entomological results revealed a significant decline in both Anopheles species and An. culicifacies (P < 0.0001).

Conclusion  A combination of indoor residual spraying and early detection and prompt treatment complemented by rapid diagnostic tests and larvivorous fishes successfully brought malaria under control. These approaches could be applied in other regions of different endemicity to control malaria in India.

Keywords malaria, tribal
, Plasmodium falciparum,
forest
, Anopheles culicifacies, vector
Epidemiologic survey of pemphigus vulgaris with oral manifestations in northern Greece: Retrospective study of 129 patients
Authors: Michailidou Evangelia Z. , Belazi Maria A. , Markopoulos Anastasios K. , Tsatsos Michael I. , Mourellou Olga N. , Antoniades Demetrios Z.
Published: September 2006

Objective  To evaluate the epidemiology of pemphigus vulgaris (PV) in a Greek population and to compare it with other countries.

Materials and Methods  A retrospective study was conducted based on the records of 129 patients (41 males and 88 females) with PV who visited the Department of the Oral Medicine and Maxillofacial Pathology, Aristotle University of Thessaloniki, Greece and the State Hospital for Skin and Venereal Diseases of Thessaloniki, Greece, between 1985 and 2004. A group of 73 individuals was used as controls.

Results  The average annual incidence was found to be eight patients per year. The male to female ratio was 1 : 2.25. The difference in the age of onset between the two genders was statistically significant in marginal levels (P = 0.05). In addition, 86.1% of the patients showed oral lesions only, 13.3% oral and skin lesions and 1.3% manifested oral, skin, and ocular lesions. Twenty‐eight of the 88 females were in the premenopausal period‐of‐life. Additionally, 19 males were farmers who had daily contact with organophosphoric pesticides. Co‐existing pathologic conditions were present in 75 of the 129 patients, and of these 75 patients six (8%) were diabetics, 15 (20%) presented with hypertension, two (2.6%) faced problems from their thyroid gland, and 10 (13.3%) of the patients complained of allergic reactions.

Conclusions  The results of this study demonstrated a relatively high incidence of PV in northern Greece compared with that in other countries. The disease most frequently occured in the sixth decade‐of‐life and the majority of the patients manifested oral lesions. Further epidemiological studies are needed to elucidate whether this region is constituted from population groups with high susceptibility to PV.
Large body size in an island‐dwelling bird: a microevolutionary analysis
Authors: FRENTIU F. D. , CLEGG S. M. , BLOWS M. W. , OWENS I. P. F.
Published: September 2006

Island races of passerine birds display repeated evolution towards larger body size compared with their continental ancestors. The Capricorn silvereye (Zosterops lateralis chlorocephalus) has become up to six phenotypic standard deviations bigger in several morphological measures since colonization of an island approximately 4000 years ago. We estimated the genetic variance–covariance (G)matrix using full‐sib and ‘animal model’ analyses, and selection gradients, for six morphological traits under field conditions in three consecutive cohorts of nestlings. Significant levels of genetic variance were found for all traits. Significant directional selection was detected for wing and tail lengths in one year and quadratic selection on culmen depth in another year. Although selection gradients on many traits were negative, the predicted evolutionary response to selection of these traits for all cohorts was uniformly positive. These results indicate that theGmatrix and predicted evolutionary responses are consistent with those of a population evolving in the manner observed in the island passerine trend, that is, towards larger body size.
Stimulation of Rice (Oryza sativa L.) Seedling Vigour by Smoke‐water and Butenolide
Authors: Kulkarni M. G. , Sparg S. G. , Light M. E. , Van Staden J.
Published: September 2006

The newly identified smoke‐compound butenolide (3‐methyl‐2H‐furo[2,3‐c]pyran‐2‐one) can improve seedling vigour. This study highlights the effects of smoke‐water and butenolide on shoot and root elongation of a local rice variety. Smoke‐water (1 : 500) and butenolide (10−8 m) treatments significantly increased shoot length. A low concentration of butenolide (10−10 m) promoted maximum root length and seedling weight, which were significantly different from the control. Butenolide‐treated (10−8 m) seedlings had a significantly greater number of lateral roots than untreated seedlings. The vigour index of smoke‐water (1 : 500) and butenolide‐treated (10−8 m) rice seeds was significantly higher than that of untreated seeds. These findings suggest the possible use of butenolide for promoting vigorous seedlings in rice.
Effects of Storing Pig Ovaries at 4 or 20°C for Different Periods of Time on the Morphology and Viability of Pre‐Antral Follicles
Authors: Lucci CM , Schreier LL , Machado GM , Amorim CA , Báo SN , Dobrinsky JR
Published: September 2006

Contents

The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre‐antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20°C for 6, 12 or 18 h. After storage, pre‐antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20°C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4°C for 18 h and at 20°C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4°C for up to 18 h or at 20°C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro.
Pregnancy Diagnosis in Cats Using a Rapid, Bench‐top Kit to Detect Relaxin in Urine
Authors: De Haas van Dorsser FJ , Lasano S , Steinetz BG
Published: September 2006

Contents

Relaxin is a pregnancy‐specific hormone in the queen and is produced by the placenta. Both serum and urinary relaxin levels can be used to diagnose and monitor pregnancy in the cat; however, only serum levels are commonly measured in practice. The present study aimed to assess whether urine could be used for the rapid diagnosis of pregnancy at an early stage in domestic cats using a bench‐top kit to detect relaxin. Paired serum and urine samples were collected during the first month of gestation in six cats. The samples were tested by applying neat serum, urine or urine diluted in non‐pregnant cat serum to the Witness Relaxin kit. Relaxin concentrations in the paired samples were also measured by radioimmunoassay. All undiluted urine samples from pregnant cats tested negative using the bench‐top kit; however, the kit was able to detect relaxin in urine after dilution with non‐pregnant cat serum. Using this as the test sample, the kit was accurate at diagnosing pregnancy from 28 days after mating and some samples tested positive at 21 days after mating. This preliminary work could lead to the development of a home pregnancy test for cats.
Inactivation of the ventromedial prefrontal cortex reduces expression of conditioned fear and impairs subsequent recall of extinction
Authors: Sierra‐Mercado Demetrio , Corcoran Kevin A. , Lebrón‐Milad Kelimer , Quirk Gregory J.
Published: September 2006

Anxiety disorders are thought to reflect deficits in the regulation of fear expression. Evidence from rodent studies implicates the ventromedial prefrontal cortex (vmPFC) in the regulation of conditioned fear. Lesions of the vmPFC have had differing effects on the acquisition and expression of conditioned fear, as well as on recall of extinction. The use of permanent lesions, however, makes it difficult to assess the phase of training in which the vmPFC is acting and can trigger recruitment of other structures, thereby masking lesion deficits. To overcome these problems, we temporarily inactivated the vmPFC of rats with tetrodotoxin (10 ng in a 0.5‐µl midline infusion) at one of four time points: prior to conditioning, prior to extinction, immediately after extinction or prior to recall of extinction. Consistent with lesion findings, inactivation of the vmPFC prior to acquisition had no effect but inactivation prior to extinction led to impaired recall of extinction the following day. In contrast to lesion findings, inactivation of the vmPFC decreased freezing at all time points, suggesting that some component of the vmPFC facilitates the expression of conditioned fear. These findings suggest that inactivation of the vmPFC can have opposite effects depending on the phase of training. The vmPFC appears to be involved both in stimulating the expression of conditioned fear and in serving as a site of extinction‐related plasticity that inhibits fear during recall of extinction.
Evolutionarily‐conserved role of the NF‐κB transcription factor in neural plasticity and memory
Authors: Romano Arturo , Freudenthal Ramiro , Merlo Emiliano , Routtenberg Aryeh
Published: September 2006

NF‐κB is an evolutionarily conserved family of transcription factors (TFs) critically involved in basic cellular mechanisms of the immune response, inflammation, development and apoptosis. In spite of the fact that it is expressed in the central nervous system, particularly in areas involved in memory processing, and is activated by signals such as glutamate and Ca2+, its role in neural plasticity and memory has only recently become apparent. A surprising feature of this molecule is its presence within the synapse. An increasing number of reports have called attention to the role of this TF in processes that require long‐term regulation of the synaptic function underlying memory and neural plasticity. Here we review the evidence regarding a dual role for NF‐κB, as both a signalling molecule after its activation at the synapse and a transcriptional regulator upon reaching the nucleus. The specific role of this signal, as well as the general transcriptional mechanism, in the process of memory formation is discussed. Converging lines of evidence summarized here point to a pivotal role for the NF‐κB transcription factor as a direct signalling mechanism in the regulation of gene expression involved in long‐term memory.
Specialization of the specialized in features of external human brain morphology
Authors: Bangert Marc , Schlaug Gottfried
Published: September 2006

Recent studies have shown brain differences between professional musicians and non‐musicians with respect to size, asymmetry or gray matter density of specific cerebral regions. Here we demonstrate: (1) that anatomical differences in the motor cortex can already be detected by coarse visual inspection; and (2) that within musicians, even a discrimination of instruments with different manual dominance is possible on a gross anatomical scale. Multiple raters, blinded for subject identity and hemisphere, investigated within‐musician differences in the Omega Sign (OS), an anatomical landmark of the precentral gyrus associated with hand movement representation. The sample of 64 brains comprised matched groups of 16 expert string‐players, 16 expert pianists and 32 non‐musicians. Ratings were analysed by means of kappa statistics. Intra‐ and interobserver reliabilities were high. Musicians had a more pronounced OS expression than non‐musicians, with keyboard‐players showing a left and string‐players a right hemisphere advantage. This suggests a differential brain adaptation depending on instrument played.
Differential effect of cannabinoid agonists and endocannabinoids on histamine release from distinct regions of the rat brain
Authors: Cenni Gabriele , Blandina Patrizio , Mackie Ken , Nosi Daniele , Formigli Lucia , Giannoni Patrizia , Ballini Chiara , Della Corte Laura , Francesco Mannaioni Pier , Beatrice Passani M.
Published: September 2006

Cannabinoids exert complex actions on neurotransmitter systems involved in cognition, locomotion, appetite, but no information was available so far on the interactions between the endocannabinoid system and histaminergic neurons that command several, similar behavioural states and memory. In this study, we investigated the effect of cannabimimetic compounds on histamine release using the microdialysis technique in the brain of freely moving rats. We found that systemic administration of the cannabinoid receptors 1 (CB1‐r) agonist arachidonyl‐2′chloroethylamide/N‐(2chloroethyl)‐5Z,8Z,11Z,14Z‐eicosatetraenamide (ACEA; 3 mg/kg) increased histamine release from the posterior hypothalamus, where the histaminergic tuberomamillary nuclei (TMN) are located. Local infusions of ACEA (150 nm) or R(+)‐methanandamide (mAEA; 1 µm), another CB1‐r agonist, in the TMN augmented histamine release from the TMN, as well as from two histaminergic projection areas, the nucleus basalis magnocellularis and the dorsal striatum. When the endocannabinoid uptake inhibitor AM404 was infused into the TMN, however, increased histamine release was observed only in the TMN. The cannabinoid‐induced effects on histamine release were blocked by co‐administrations with the CB1‐r antagonist AM251. Using double‐immunofluorescence labelling and confocal laser‐scanning microscopy, CB1‐r immunostaining was found in the hypothalamus, but was not localized onto histaminergic cells. The modulatory effect of cannabimimetic compounds on histamine release apparently did not involve inhibition of γ‐aminobutyric acid (GABA)ergic neurotransmission, which provides the main inhibitory input to the histaminergic neurons in the hypothalamus, as local infusions of ACEA did not modify GABA release from the TMN. These profound effects of cannabinoids on histaminergic neurotransmission may partially underlie some of the behavioural changes observed following exposure to cannabinoid‐based drugs.
Functional redundancy of NSCL‐1 and NeuroD during development of the petrosal and vestibulocochlear ganglia
Authors: Krüger Marcus , Schmid Thomas , Krüger Sonja , Bober Eva , Braun Thomas
Published: September 2006

To study the role of different members of the bHLH gene family for sensory organ development we have generated NSCL‐1 and NeuroD compound‐mutant mice. Double homozygous animals were characterized by a more severe reduction of the petrosal and vestibulocochlear ganglia than NeuroD‐knockout mice. The more severe reduction of the petrosal and vestibulocochlear ganglia in double‐knockout mice indicates overlapping functions of the two genes during neuronal development. Interestingly, we also found that the two genes are jointly regulated by thyroid hormone during sensory hair cell development. We further present a detailed expression analysis of NSCL‐1 and NSCL‐2 during sensory neuron development. NSCL‐1 expression was detected in all developing cranial ganglia including the petrosal and vestibulocochlear ganglion, in inner and outer hair cells of the organ of Corti and in hair cells of the vestibular system. Expression domains in other sensory structures include the retina, Merkel cells of the developing skin and sensory cells of the tongue. The expression of NSCL‐2 was restricted to developing cranial ganglia, the retina and the vestibular nerve. Both NSCL‐1 and NSCL‐2 genes are active only in postmitotic neurons, indicating a role for neuronal cell migration and/or differentiation within the sensory system.
Nyctalopin is essential for synaptic transmission in the cone dominated zebrafish retina
Authors: Bahadori Ronja , Biehlmaier Oliver , Zeitz Christina , Labhart Thomas , Makhankov Yuri V. , Forster Ursula , Gesemann Matthias , Berger Wolfgang , Neuhauss Stephan C. F.
Published: September 2006

The first synapse in the vertebrate visual system is the photoreceptor synapse between rod and cone photoreceptors and the second‐order bipolar cells. Although mutations in the nyctalopin gene (NYX) in humans lead to congenital stationary night blindness (CSNB1), affecting synaptic transmission between both types of photoreceptors and ON‐bipolar cells, the function of nyctalopin in cone‐dominant animal models has not been studied. Because the larval zebrafish retina is cone‐dominant, we isolated the zebrafish nyx ortholog and raised a polyclonal antibody against the protein. Nyctalopin is expressed postsynaptically in both synaptic layers of the retina. Functional disruption via morpholino antisense injection leads to characteristic defects in the electroretinogram and defects in visual contrast sensitivity. We therefore demonstrated that nyctalopin plays a similar role in retinal synapse function in the cone pathway as in the rod pathway, thereby creating a genetic model for CSNB1 and its effects on cone vision.
Competition between glucose and lactate as oxidative energy substrates in both neurons and astrocytes: a comparative NMR study
Authors: Bouzier‐Sore Anne‐Karine , Voisin Pierre , Bouchaud Véronique , Bezancon Eric , Franconi Jean‐Michel , Pellerin Luc
Published: September 2006

Competition between glucose and lactate as oxidative energy substrates was investigated in both primary cultures of astrocytes and neurons using physiological concentrations (1.1 mm for each). Glucose metabolism was distinguished from lactate metabolism by using alternatively labelled substrates in the medium ([1‐13C]glucose + lactate or glucose + [3‐13C]lactate). After 4 h of incubation, 1H and 13C‐NMR spectra were realized on perchloric acid extracts of both cells and culture media. For astrocytic cultures, spectra showed that amino acids (glutamine and alanine) were more labelled in the glucose‐labelled condition, indicating that glucose is a better substrate to support oxidative metabolism in these cells. The opposite was observed on spectra from neuronal cultures, glutamate being much more labelled in the lactate‐labelled condition, confirming that neurons consume lactate preferentially as an oxidative energy substrate. Analysis of glutamine and glutamate peaks (singlets or multiplets) also suggests that astrocytes have a less active oxidative metabolism than neurons. In contrast, they exhibit a stronger glycolytic metabolism than neurons as indicated by their high lactate production yield. Using a mathematical model, we have estimated the relative contribution of exogenous glucose and lactate to neuronal oxidative metabolism. Under the aforementioned conditions, it represents 25% for glucose and 75% for lactate. Altogether, these results obtained on separate astrocytic and neuronal cultures support the idea that lactate, predominantly produced by astrocytes, is used as a supplementary fuel by neurons in vivo already under resting physiological conditions.
Microbial communities in a porphyry copper tailings impoundment and their impact on the geochemical dynamics of the mine waste
Authors: Diaby Nouhou , Dold Bernhard , Pfeifer Hans‐Rudolf , Holliger Christof , Johnson D. Barrie , Hallberg Kevin B.
Published: September 2006

The distribution and diversity of acidophilic bacteria of a tailings impoundment at the La Andina copper mine, Chile, was examined. The tailings have low sulfide (1.7% pyrite equivalent) and carbonate (1.4% calcite equivalent) contents and are stratified into three distinct zones: a surface (0‐70‐80 cm) ‘oxidation zone’ characterized by low‐pH (2.5–4), a ‘neutralization zone’ (70–80 to 300–400 cm) and an unaltered ‘primary zone’ below 400 cm. A combined cultivation‐dependent and biomolecular approach (terminal restriction enzyme fragment length polymorphism and 16S rRNA clone library analysis) was used to characterize the indigenous prokaryotic communities in the mine tailings. Total cell counts showed that the microbial biomass was greatest in the top 125 cm of the tailings. The largest numbers of bacteria (109 g−1 dry weight of tailings) were found at the oxidation front (the junction between the oxidation and neutralization zones), where sulfide minerals and oxygen were both present. The dominant iron‐/sulfur‐oxidizing bacteria identified at the oxidation front included bacteria of the genus Leptospirillum (detected by molecular methods), and Gram‐positive iron‐oxidizing acidophiles related to Sulfobacillus (identified both by molecular and cultivation methods). Acidithiobacillus ferrooxidans was also detected, albeit in relatively small numbers. Heterotrophic acidophiles related to Acidobacterium capsulatum were found by molecular methods, while another Acidobacterium‐like bacterium and an Acidiphilium sp. were isolated from oxidation zone samples. A conceptual model was developed, based on microbiological and geochemical data derived from the tailings, to account for the biogeochemical evolution of the Piuquenes tailings impoundment.
Orthogonality is not a panacea: Backpropagation and “catastrophic interference”
Authors: YAMAGUCHI MAKOTO
Published: September 2006

Connectionist models with the backpropagation learning rule are said to exhibit catastrophic interference (or forgetting) with sequential training. Subsequent works showed that interference can be reduced by using orthogonal inputs. This study investigated, with a more rigorous assessment method, whether all orthogonal inputs lead to comparable extent of interference using three coding schemes. The results revealed large differences between the coding schemes. With larger networks, dense inputs led to severer interference compared with sparse inputs. With smaller networks, all the three schemes led to comparable extent of interference. Therefore, this study proved that not all the orthogonal inputs cause the same extent of interference, and that severity of interference depends on the interaction of the input coding scheme and the network size.