bluuebunny/crossref_metadata_2025_split huggingface dataset:
The characterization of sardine (Sardina pilchardus Walbaum) schools off the Spanish-Atlantic coast
Authors: Muiño Ramón , Carrera Pablo , Iglesias Magdalena 
Published: September 2003

Abstract
This paper describes the main characteristics of sardine schools detected in the Spanish-Atlantic surveys carried out from 1992 to 1997 (except 1994). A series of parameters were obtained for each school (morphological, positional and energetic) as well as environmental factors (temperature and salinity). The relationships between the school parameters were analyzed by a PCA and then the school parameters per se were described using both univariate and multivariate analyses (Box-plots, ANOVAs, MANOVA, and discriminant analysis). The results show that significant differences exist between years and geographic areas in that the Rías Baixas schools were smaller in size and of higher density than those from the Cantabric area. These differences could be related to the facts that the Rías Baixas is a nursery zone and sardine length and age are smaller than in the Cantabric Sea. It would seem that the differences in school morphology and energetic characteristics related to length and age of individuals allow us to distinguish between the sardine echo traces in this area. There is a high annual variability in the number of schools and this is not a function of either survey design or strategy and it is not related to the abundance estimates of sardine. These results are important for both future species identification and the improvement of survey design and strategy.
Gene expression in HCV‐associated hepatocellular carcinoma – upregulation of a gene encoding a protein related to the ubiquitin‐conjugating enzyme
Authors: El‐Nady Ghada M. , Ling Roger , Harrison Tim J. 
Published: September 2003

Abstract:Background/Aim: To investigate gene expression in HCV‐associated human hepatocellular carcinomas (HCC) by identifying up‐ and down‐regulated genes.Methods:  Differential display RT‐PCR was used to compare levels of gene expression in tumorous and non‐tumorous tissues from the same livers. Differential expression was confirmed using a ribonuclease protection assay (RPA). The relative expression levels of one candidate gene were studied in various normal tissues and malignant cell lines using a multiple tissue expression (MTE) array. Further characterisation of this gene was carried out using nucleotide sequence analysis programmes and Northern hybridisation.Results:  Fifty‐two differentially expressed cDNA fragments were identified and 29 were cloned, sequenced and compared with the nucleotide sequence database. RPA confirmed reproducibly that one particular cDNA was upregulated in the tumour cells. Analysis using the MTE array revealed that this selected candidate gene is expressed at high levels in various human tumour cell lines. The expression levels in HCV‐associated HCC were higher than in other tumours. Investigation revealed that this novel gene lies on chromosome 17. The transcript is approximately 2.5 kb in size and encodes a protein similar to the ubiquitin‐conjugating enzyme.Conclusions:  The ubiquitin system may be involved in HCV‐related hepatocarcinogenesis and in the development of other cancers.
Spatial and temporal woodland patterns along the lower Turkwel River, Kenya
Authors: Stave Jørn , Oba Gufu , Bjorå Charlotte S. , Mengistu Zelalem , Nordal Inger , Stenseth Nils C. 
Published: September 2003

AbstractSpatial and temporal patterns of riverine woodlands in arid regions of Africa are poorly documented despite their considerable conservation value. We studied 1540 ha of riverine woodland in the lower Turkwel River floodplain, Kenya, between 1990 and 1998. Forty‐one woodland patches were mapped and their soil physical and chemical characteristics, tree species diversity, woody cover, tree density, wood volume and woodland regeneration were determined. The riverine woodland comprised nine vegetation types and a total of 14 woody species. Woodland patch mosaics were associated with microtopographical features and selected soil attributes. The most important woody species were Hyphaene compressa H. Wendl., Acacia tortilis (Forssk.) Hayne and Cadaba rotundifolia Forssk. The exotic Prosopis chilensis (Mol.) St. was invading parts of the riverine woodland. Overall, woody species diversity was low compared to similar riverine woodlands in East Africa. Tree density, wood volume and woody plant regeneration declined over the 8‐year study period, while woody cover was unchanged. Reduced tree density, wood volume and regeneration of woody species might be linked to changes in river flood patterns following the impoundment of the Turkwel Gorge Dam. It is suggested that spatially heterogeneous and temporally stochastic regeneration events, together with occasional tree mortality caused by channel abandonment, create the complex pattern of woodland patches in the lower Turkwel River floodplain. The mapped woodland patches may serve as monitoring units, which in future could reveal the interplay between changes in flooding patterns as a result of dam impoundment, anthropogenic disturbance and the well‐being of the riverine woodlands.
Towards a density measure for assessments of arid plant populations – examples from the southern Namib Desert
Authors: Burke Antje , Mannheimer Coleen 
Published: September 2003

AbstractPlant species in arid environments are often widely spaced making population assessments difficult. In order to minimise observer bias we tested two repeatable simple methods during red data assessments in the southern Namib Desert. Both the transect‐based and the quadrat‐based method resulted in over‐estimates of the true population size. However, because of case of application, the transect method warrants further development.
Effect of dietary oregano oil and α‐tocopheryl acetate supplementation on iron‐induced lipid oxidation of turkey breast, thigh, liver and heart tissues
Authors: Papageorgiou G. , Botsoglou N. , Govaris A. , Giannenas I. , Iliadis S. , Botsoglou E. 
Published: September 2003

SummaryTwenty‐five 12‐week‐old turkeys randomly divided into five groups were given a basal diet, or a basal diet supplemented with 200 mg α‐tocopheryl acetate/kg, or 100 mg oregano oil/kg or 200 mg oregano oil/kg, or 100 mg oregano oil plus 100 mg α‐tocopheryl acetate/kg diet, for 4 weeks prior to slaughter. Breast, thigh, liver and heart tissues were subjected to iron‐induced lipid oxidation, the extent of which was determined by third‐order derivative spectrophotometry. Results showed that dietary oregano oil at the inclusion level of 200 mg oregano oil/kg diet was more effective in delaying lipid oxidation compared with the inclusion level of 100 mg/kg, but equivalent to the inclusion of 200 mg α‐tocopheryl acetate/kg diet, which in turn was inferior to the combined inclusion of 100 mg oregano oil plus 100 mg α‐tocopheryl acetate/kg, which was superior to all dietary treatments. Thigh tissue was more susceptible to oxidation than breast tissue, although it contained α‐tocopherol at higher concentrations. Also, lipid oxidation in heart was relatively high, although it contained the highest α‐tocopherol levels. This indicates that tissue α‐tocopherol is one important factor influencing the level of lipid oxidation, but the distribution of lipids, iron and oregano oil in tissues must also be taken into consideration. Tissue α‐tocopherol levels responded to dietary intake of 30–200 mg α‐tocopheryl acetate/kg in the order heart > liver > thigh > breast. Breast, thigh and heart tissues from the oregano groups presented significantly (p < 0.05) higher levels of α‐tocopherol compared with the control, the increase being positively correlated with the supplementation level. The increased levels of α‐tocopherol in these tissues indicated that the dietary oregano oil exerted a protective action on α‐tocopherol.
Tryptophan requirement of growing pigs at various body weights
Authors: Eder K. , Nonn H. , Kluge H. , Peganova S. 
Published: September 2003

SummaryThe purpose of this study was to determine the tryptophan (Trp) requirement of growing pigs at different body weight (BW) ranges. Three performance experiments were conducted with female pigs in the BW ranges of 25–50, 50–80 and 80–115 kg. In addition to the performance experiments, nitrogen balance experiments were carried out in which pigs weighing 56, 66 and 86 kg were used. Trp‐deficient basal diets were formulated to which varying amounts of l‐Trp were added. The amino acid concentrations of the diets were analysed; concentrations of standardized digestible amino acids were calculated on the basis of tabular values. The calculated concentrations of standardized ileal digestible tryptophan were 0.81, 1.11, 1.41, 1.71, 2.01 g/kg diet in the lower BW range (25–50 kg), 0.71, 0.96, 1.21, 1.46, 1.71 g/kg diet in the middle BW range (50–80 kg), and 0.49, 0.69, 0.89, 1.09, 1.29 g/kg diet in the upper BW range (80–115 kg). Dose–response relationships were evaluated by means of an exponential regression model. In all three age ranges, performance parameters as well as nitrogen retention were strongly influenced by the dietary concentration of standardized ileal digestible tryptophan. According to the exponential model, in the 25–50 kg BW range, 95% of the maximum feed consumption, BW gain and nitrogen retention were achieved at concentrations between 1.96 and 2.00 g of standardized ileal digestible Trp per kilogram diet, corresponding to 3.32–3.39 g/day. In the BW range of 50–80 kg, 95% of the maximum of these parameters occurred at concentrations of standardized ileal digestible tryptophan in excess of the highest concentration of 1.71 g/kg diet, corresponding to 3.71 g/day. In the BW range of 80–115 kg, 95% of the maximum of BW gain and nitrogen retention were recorded at concentrations of 1.22 and 0.84 g standardized ileal digestible Trp per kilogram diet, corresponding to 3.77 and 2.25 g/day, respectively. Related to the energy value of the diets, the optimal concentration of standardized ileal digestible tryptophan are between 140 and 143 mg/MJ metabolizable energy (ME) in the BW range of 25–50 kg, in excess of 127 mg/MJ ME in the BW range of 50–80 kg and between 62 and 90 mg/MJ ME in the BW range of 80–115 kg. In conclusion, it is suggested that the requirement of standardized ileal digestible tryptophan for growing pigs might be higher than currently assumed.
Expression of the Major Outer Membrane Protein (MOMP) of Chlamydophila abortus, Chlamydophila pecorum, and Chlamydia suis in Escherichia coli using an Arabinose‐inducible Plasmid Vector
Authors: Hoelzle L. E. , Hoelzle K. , Wittenbrink M. M. 
Published: September 2003

SummaryThe ompA genes encoding the 40 kDa major outer membrane protein (MOMP) of Chlamydophila (Ch.) abortus, Ch. pecorum, and Chlamydia (C.) suis were cloned into the arabinose‐inducible plasmid vector pBADMycHis, and recombinant MOMPs (rMOMP) from the three chlamydial species were expressed at high levels in Escherichia (E.) coli. The proteins lacking the 22 aa N‐terminal signal peptide were expressed as insoluble cytoplasmic inclusion bodies which were readily purified using immobilized metal‐affinity chromatography. The rMOMPs including the N‐terminal signal peptide were expressed and translocated as a surface‐exposed immunoaccessible protein into the outer membrane of E. coli. Transformants expressing this full‐length rMOMP were significantly reduced in viability. Purified native elementary bodies (EB) and rMOMPs of the three chlamydial species purified from the E. coli cytoplasm were used for immunization of rabbits. The resulting sera were analysed for their ability to recognize homologous and heterologous rMOMP and native EB. When testing rMOMP antisera against rMOMP and EB antigens, marked cross‐reactivities were detected between the three species. Using EB antisera and rMOMPs as antigens, a significant species‐specific reactivity was measured.
The Effect of Kefir on the Activities of GSH‐Px, GST, CAT, GSH and LPO Levels in Carbon Tetrachloride‐Induced Mice Tissues
Authors: Güven A. , Güven A. , Gülmez M. 
Published: September 2003

SummaryFunctional foods including kefir have increasingly become as popular as before in the developing world. The health benefits of kefir including the antioxidative effects are still under evaluation. Vitamin E is also a well‐known antioxidant. The biologically damaging effects of reactive oxygen species are controlled in vivo by a wide spectrum of antioxidant defence mechanisms. Dietary constituents of antioxidative vitamins and other nutrients may play an important role in protecting the body against oxidative damage. The study was carried out to investigate the protective effect of kefir against oxidative damage of CCl4 in mice, compared with the well‐known antioxidant vitamin E. Three‐week‐old Swiss Albino mice, weighing 22–26 g were used for the experiment. At the end of the microbiological analysis of kefir, the averages of the total mesophilic aerobic colony counts, lactic acid bacteria, lactic streptococci, enterococci, and yeasts were found to be 1.04 × 109, 9.87 × 108, 4.38 × 108, 7.80 × 104 and 1.26 × 105 CFU/ml, respectively. While both vitamin E and kefir were found to have a protective effect aganist CCl4‐induced damage, kefir was more protective. This may probably be the first study to compare the antioxidative action of kefir and vitamin E in the animal model.
Herd Management Practices Associated with Paratuberculosis Seroprevalence in Dutch Dairy Herds
Authors: Muskens J. , Elbers A. R. W. , Van Weering H. J. , Noordhuizen J. P. T. M. 
Published: September 2003

SummaryWe describe the paratuberculosis management practices applied in dairy herds in the Netherlands. The findings from paratuberculosis seronegative and seropositive herds were compared to discover possible risk factors. In total, 370 randomly selected herds with ≥20 dairy cows were surveyed. A questionnaire was used to collect data on current and previous paratuberculosis management practices. All cattle aged ≥3 years were serologically tested for paratuberculosis using an enzyme‐linked immunosorbent assay. Herds with >33 tested cattle, of which only one was seropositive, were excluded to reduce the risk of including false‐positive herds in the analysis. A comparison of the management data of the seronegative herds (n = 166) and the seropositive herds (n = 143) showed that in both groups important management measures for the prevention of paratuberculosis, such as calving in a cleaned calving area, removing the calf immediately after birth, and feeding paratuberculosis non‐suspect roughage to calves, were used only rarely. However, such measures should be regarded as the critical first step to control the disease and/or reduce its prevalence. Using univariable analysis, four factors were statistically different between seronegative and seropositive herds: herd size, cows with clinical signs of paratuberculosis, prompt selling of clinically diseased cattle and feeding milk replacer. Using a multivariable logistic regression model, only herd size was a significantly different factor. These results indicate that most of the paratuberculosis preventive management measures were executed on these Dutch dairy farms only to a limited extent.
Expression and plasticity of galanin systems in cortical neurons, oligodendrocyte progenitors and proliferative zones in normal brain and after spreading depression
Authors: Shen Pei‐Juan , Larm Jari A. , Gundlach Andrew L. 
Published: September 2003

AbstractNeocortex contains very few galanin neurons but receives a moderate galanin innervation from various subcortical loci. Recent data suggest that galanin helps regulate the tonic neuronal excitability of hippocampus and probably cerebral cortex but relatively little is known about the anatomy and functional regulation of cortical galanin systems. Therefore, we examined, in the rat, the effect of the intense but benign stimulus, cortical spreading depression (CSD), on the expression of galanin and galanin receptors (GalR1 and GalR2) in the neocortex and associated regions, revealing complex, multicellular responses. Thus, following acute, unilateral KCl‐induced CSD, a delayed and transient induction (onset after 48 h, lasting ∼24 h) of galanin mRNA and peptide production occurred across the ipsilateral cerebral cortex in activated oligodendrocyte progenitor cells (OPCs), identified by specific NG2 proteoglycan immunostaining. An increase in GalR1 mRNA, immunoreactivity and receptor binding occurred in neurons within layers II and V of neocortex and in piriform cortex at 7–28 days after CSD, associated with a long‐lasting depletion of galanin‐positive nerve fibres in these regions. In contrast, GalR2 mRNA expression was largely unaltered after CSD. Additional novel findings in normal, adult brain were the detection of galanin mRNA and immunoreactivity in OPCs within the medial corpus callosum and in immature progenitor cells in the subventricular zone and rostral migratory stream. GalR1 and GalR2 mRNA was also present in these latter regions. These findings and the complex modulation of galanin and galanin receptors in multiple cell types (neurons/OPCs) following acute cortical activation/depression further demonstrate the potential plasticity of neuronal and non‐neuronal galanin systems under physiological and pathological conditions and strongly suggest additional functions for this pleiotropic peptide in mammalian brain.
Depolarization differentially affects the secretory and migratory properties of two cell lines of immortalized luteinizing hormone‐releasing hormone (LHRH) neurons
Authors: Pimpinelli Federica , Redaelli Elisa , Restano‐Cassulini Rita , Curia Giulia , Giacobini Paolo , Cariboni Anna , Wanke Enzo , Bondiolotti Gian Pietro , Piva Flavio , Maggi Roberto 
Published: September 2003

AbstractIn this report we studied and compared the biochemical and the electrophysiological characteristics of two cell lines (GT1‐7 and GN11) of immortalized mouse LHRH‐expressing neurons and the correlation with their maturational stage and migratory activity. In fact, previous results indicated that GN11, but not GT1‐7, cells exhibit an elevated motility in vitro. The results show that the two cell lines differ in terms of immunoreactivity for tyrosine hydroxylase and nestin as well as of production and release of 3,4‐dihydroxyphenylalanine (DOPA) and of intracellular distribution and release of the LHRH. Patch‐clamp recordings in GN11 cells, reveal the presence of a single inward rectifier K+ current indicative of an immature neuronal phenotype (neither firing nor electrical activity). In contrast, as known from previous studies, GT1‐7 cells show the characteristics of mature LHRH neurons with a high electrical activity characterized by spontaneous firing and excitatory postsynaptic potentials. K+‐induced depolarization induces in GT1‐7 cells, but not in GN11 cells, a strong increase in the release of LHRH in the culture medium. However, depolarization of GN11 cells significantly decreases their chemomigratory response. In conclusion, these results indicate that GT1‐7 and GN11 cells show different biochemical and electrophysiological characteristics and are representative of mature and immature LHRH neurons, respectively. The early stage of maturation of GN11 cells, as well as the low electrical activity detected in these cells, appears to correlate with their migratory activity in vitro.
GABAergic control of neuropeptide gene expression in parvocellular neurons of the hypothalamic paraventricular nucleus
Authors: Bali Balázs , Kovács Krisztina J. 
Published: September 2003

AbstractTo assess the functional impact of local inhibitory γ‐aminobutyric acid (GABA)ergic interneuron population on the cellular and transcriptional activity of parvocellular neurosecretory neurons in the hypothalamic paraventricular nucleus (PVH), we followed the expression of corticotropin‐releasing hormone (CRH) and arginine vasopressin (AVP) genes along with the activation marker c‐fos in response to the blockade of GABA‐A receptors. First, we analysed the effect of the GABA‐A receptor antagonist bicuculline methiodide (BMI) in organotypic cultures of hypothalamic slices. These preparations preserve the cytoarchitecture of CRH‐synthesizing cell populations and elements of local interneuronal networks, while remote connections originating from limbic‐ and brainstem areas are missing. In vitro, BMI resulted in a selective induction of c‐Fos immunoreactivity that was localized exclusively to the PVH and upregulated both CRH mRNA and AVP hnRNA levels. Local microinjection of BMI into the paraventricular region of freely moving rats increased the adrenocorticotropin secretion and activated PVH neurons ipsilateral to the injection. c‐Fos immunoreactivity was distributed within the PVH and in the perinuclear region, where it appeared in GABAergic and also in non‐GABAergic profiles. This treatment induced AVP hnRNA expression in the parvocellular compartment without any reliable stimulation of CRH transcription in the parvocellular‐ and AVP hnRNA levels in the magnocellular neurons. These results reveal an intrinsic GABAergic mechanism in the PVH microenvironment that by itself, without limbic contribution, impinges a tonic inhibitory influence on the parvocellular CRH neurons in vitro. In vivo, remote inputs are superimposed on the local circuit, allowing differential transcriptional regulation of CRH and AVP genes in the hypophyseotropic neurons.
Homer1 proteins and AMPA receptors modulate cocaine‐induced behavioural plasticity
Authors: Ghasemzadeh M. Behnam , Permenter Lindsay K. , Lake Russell , Worley Paul F. , Kalivas Peter W. 
Published: September 2003

AbstractHomer proteins form functional assemblies in the excitatory postsynaptic density, and withdrawal from repeated cocaine administration reduces the expression of Homer1b/c in the nucleus accumbens. To determine if the reduction in Homer1b/c may be contributing to cocaine‐induced behavioural sensitization, antisense oligonucleotides were infused over two weeks into the nucleus accumbens of rats to reduce Homer1 gene expression by approximately 35%. Infusion of antisense sequences (AS1 and AS2) caused a sensitization‐like augmentation in the motor response to acute cocaine administration in naive rats. One of the sequences (AS1) also prevented the development of sensitization to repeated cocaine treatment, while AS2 was without effect. A panel of immunoblots for other proteins in the excitatory postsynaptic density revealed that AS1, but not AS2 reduced the level of the α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid (AMPA) receptor subunit GluR1 protein. This posed the possibility that altered AMPA signalling may mediate the inhibitory effect of AS1 on the development of sensitization. To examine this possibility, rats were pretreated in the accumbens with drugs to block AMPA/kainate, N‐methyl‐d‐aspartate, group 1 metabotropic glutamate or dopamine receptors prior to each daily injection of cocaine. Only AMPA/kainate receptor blockade prevented the development of behavioural sensitization to cocaine. These data indicate that the expression of behavioural sensitization arises in part from a reduction in Homer1 gene products in the accumbens, while the development of sensitization requires stimulation of AMPA/kainate receptors.