bluuebunny/crossref_metadata_2025_split huggingface dataset:
Possible solutions to some challenges facing fisheries scientists and managers
Authors: Peterman Randall M. 
Published: October 2004

AbstractThe purpose of this paper is to review recent work on four key challenges in fisheries science and management: (1) dealing with pervasive uncertainties and risks; (2) estimating probabilities for uncertain quantities; (3) evaluating performance of proposed management actions; and (4) communicating technical issues. These challenges are exacerbated in fisheries that harvest multiple stocks, and various methods provide partial solutions to them: (i) risk assessments and decision analyses take uncertainties into account by permitting several alternative hypotheses to be considered at once. (ii) Hierarchical models applied to multi-stock data sets can improve estimates of probability distributions for model parameters compared with those derived through single-stock analyses. (iii) Operating models of complete fishery systems provide comprehensive platforms for testing management procedures. (iv) Finally, results from research in such other disciplines as cognitive psychology can facilitate better communication about uncertainties and risks among scientists, managers, and stakeholders.
From single-species advice to mixed-species management: taking the next step
Authors: Vinther Morten , Reeves Stuart A. , Patterson Kenneth R. 
Published: October 2004

Abstract
Fishery management advice has traditionally been given on a stock-by-stock basis. Recent problems in implementing this advice, particularly for the demersal fisheries of the North Sea, have highlighted the limitations of the approach. In the long term, it would be desirable to give advice that accounts for mixed-fishery effects, but in the short term there is a need for approaches to resolve the conflicting management advice for different species within the same fishery, and to generate catch or effort advice that accounts for the mixed-species nature of the fishery. This paper documents a recent approach used to address these problems. The approach takes the single-species advice for each species in the fishery as a starting point, then attempts to resolve it into consistent catch or effort advice using fleet-disaggregated catch forecasts in combination with explicitly stated management priorities for each stock. Results are presented for the groundfish fisheries of the North Sea, and these show that the development of such approaches will also require development of the ways in which catch data are collected and compiled.
PKC isoforms were reduced by lead in the developing rat brain
Authors: Xu Shang‐Zhi , Bullock Latoya , Shan Chun‐Juan , Cornelius Kimberly , Rajanna Bettaiya 
Published: October 2004

AbstractA plethora of protein kinase C (PKC) isoforms play important roles in regulating synaptic plasticity and neurotransmitter release. Even though, most PKC isoforms are involved in Pb‐induced neuronal toxicity, its mechanism is still unclear. The current study addresses the effect of Pb on PKC isoforms in different regions of the developing rat brain. Sprague–Dawley (SD) pregnant rats were exposed to 0.1% Pb as lead acetate dissolved in distilled deionized water (DDW) from gestation day 6 through 21 postnatal day (PND). Control rats were allowed to drink DDW. Pups were sacrificed on PND 1, 5, 10 and 45. Rat brain was immediately excised and separated into the brain stem (BS), the cerebellum (CB), the hippocampus (HC) and the frontal cortex (FC). The Pb level in different regions of the brain was determined using an analytical graphite tube atomizer (Varian). Typical PKC (α, β, γ), novel PKC (ɛ) and atypical PKC (μ) in the above brain regions were enriched by immunoprecipitation and later were assayed by Western blotting. The total, calcium‐dependent and ‐independent PKC activities were determined by the radioactivity of total γ‐32P transferred to histone. The results indicated that on PND 1, Pb reduced the PKC‐γ protein in HC and FC, whereas on PND 5 the proteins of PKC isoforms (α, β, γ, ɛ, μ) in HC and FC were significantly reduced. These reductions in PKC proteins were higher in membrane fractions than in cytosolic fractions. On PND 10, Pb reduced all PKC isoforms. However, on PND 45, Pb had no significant effect on all PKC isoforms except ɛ. Pb inhibited the total PKC activity by 70% on PND 1 and 5, the bulk of these PKC activities were calcium‐dependent. The results suggest that during early stages of the rat brain development, Pb exposure decreased PKC activities and also reduced PKC isoforms including PKC‐γ and ɛ which are reported to have roles in the memory formation and long‐term potentiation (LTP).
Induction of bone‐marrow eosinophilia in mice submitted to surgery is dependent on stress‐induced secretion of glucocorticoids
Authors: Elsas Pedro Xavier , Neto Heitor A Paula , Cheraim Alessandra B , Magalhães Elisabeth S S , Accioly Maria Theresa S , Carvalho Vinicius F , E Silva Patricia M R , Vargaftig B B , Cunha Fernando Q , Gaspar Elsas Maria Ignez C 
Published: October 2004

We examined bone‐marrow in mice receiving subcutaneous implants of heat‐coagulated egg white, which are known to present chronic eosinophilic inflammation at the implant site. Egg white implants (EWIs) induced marked bone‐marrow eosinophilia, and increased bone‐marrow cell responses to granulocyte‐macrophage colony‐stimulating factor and interleukin‐5 in culture. These effects were observed as early as 24 h and lasted for, at least, 30 days in implant recipients.
We found, however, that increased eosinophil production was also observed in control mice which underwent surgery but received no EWI (sham‐implanted mice), up to 15 days post‐surgery. As this suggests an important contribution of nonspecific stress mechanisms to eosinopoiesis, we further evaluated the role of stress hormones produced by the adrenal glands in the bone‐marrow eosinophilia of sham‐implanted mice.
Bone‐marrow eosinophilia in mice undergoing surgery was dissociated from increases in other haemopoietic lineages. Surgery by itself increased circulating corticosterone levels by 24 h, and the increase was prevented by inhibition of adrenal glucocorticoid production by metyrapone. The effect of surgery on bone‐marrow eosinophilia was prevented by pretreatment with both the glucocorticoid receptor antagonist, mifepristone, and metyrapone, and by surgical adrenalectomy.
By contrast, cathecolamine receptor antagonists (propranolol, prazosin and yohimbine) were ineffective, indicating that cathecolamine release from the adrenal glands was not responsible for the effects on bone‐marrow.
These results highlight a critical role for stress‐induced glucocorticoid hormones in selectively upregulating bone‐marrow eosinopoiesis in mice submitted to surgery.

British Journal of Pharmacology (2004) 143, 541–548. doi:10.1038/sj.bjp.0705943
The cannabinoid CB1 receptor antagonist SR141716 blocks the orexigenic effects of intrahypothalamic ghrelin
Authors: Tucci Sonia A , Rogers Elizabeth K , Korbonits Márta , Kirkham Tim C 
Published: October 2004

The paraventricular nucleus (PVN) of the hypothalamus plays a key role in the control of appetite and energy balance. Both ghrelin and cannabinoid receptor agonists increase food intake when administered into this nucleus: this study investigated possible interactions between the two systems in relation to eating. The orexigenic effect of ghrelin (100 pmol) when infused in to the PVN was reversed by a small, systemic dose of the CB1 cannabinoid receptor antagonist SR141716 (1 mg kg−1). This is the first demonstration of a functional relationship between brain ghrelin and endocannabinoid systems, and, although it needs to be further investigated, the effect of ghrelin on food intake when injected into the PVN seems to be mediated by stimulation of cannabinoid release.British Journal of Pharmacology (2004) 143, 520–523. doi:10.1038/sj.bjp.0705968
Pharmacological effects of carcinine on histaminergic neurons in the brain
Authors: Chen Zhong , Sakurai Eiko , Hu Weiwei , Jin Chunlei , Kiso Yoshinobu , Kato Motohisa , Watanabe Takehiko , Wei Erqing , Yanai Kazuhiko 
Published: October 2004

Carcinine (β‐alanyl histamine) is an imidazole dipeptide. The present study was designed to characterize the pharmacological effects of carcinine on histaminergic activity in the brain and on certain neurobehavior.
Carcinine was highly selective for the histamine H3 receptor over H1 or H2 receptor (Ki (μM)=0.2939±0.2188 vs 3621.2±583.9 or 365.3±232.8 μM, respectively).
Carcinine at a dose of 20 mg kg−1 slightly increased histidine decarboxylase (HDC) activity in the cortex (from 0.186±0.069 to 0.227±0.009 pmol mg protein−1 min−1). In addition, carcinine (10, 20, and 50 mg kg−1) significantly decreased histamine levels in mice brain.
Like thioperamide, a histamine H3 receptor antagonist, carcinine (20, 50 μM) significantly increased 5‐HT release from mice cortex slices, but had no apparent effect on dopamine release.
Carcinine (20 mg kg−1) significantly inhibited pentylenetetrazole‐induced kindling. This inhibition was completedly reversed by (R)‐α‐methylhistamine, a representative H3 receptor agonist, and α‐fluromethylhistidine, a selective HDC inhibitor.
Carcinine (20 mg kg−1) ameliorated the learning deficit induced by scopolamine. This amelioration was reversed by (R)‐α‐methylhistamine as evaluated by the passive avoidance test in mice.
Like thioperamide, carcinine dose‐dependently increased mice locomotor activity in the open‐field test.
The results of this study provide first and direct evidence that carcinine, as a novel histamine H3 receptor antagonist, plays an important role in histaminergic neurons activation and might be useful in the treatment of certain diseases, such as epilepsy, and locomotor or cognitive deficit.

British Journal of Pharmacology (2004) 143, 573–580. doi:10.1038/sj.bjp.0705978
Myosin VI: a multifunctional motor
Authors: Lister I. , Roberts R. , Schmitz S. , Walker M. , Trinick J. , Veigel C. , Buss F. , Kendrick-Jones J. 
Published: October 2004

Myosin VI moves towards the minus end of actin filaments unlike all the other myosins so far studied, suggesting that it has unique properties and functions. Myosin VI is present in clathrin-coated pits and vesicles, in membrane ruffles and in the Golgi complex, indicating that it has a wide variety of functions in the cell. To investigate the cellular roles of myosin VI, we have identified a variety of myosin VI-binding partners and characterized their interactions. As an alternative approach, we have studied the in vitro properties of intact myosin VI. Previous studies assumed that myosin VI existed as a dimer but our biochemical characterization and electron microscopy studies reveal that myosin VI is a monomer. Using an optical tweezers force transducer, we showed that monomeric myosin VI is a non-processive motor with a large working stroke of 18 nm. Potential roles for myosin VI in cells are discussed.
Isolation and identification of a protein binding to the localization element of Metallothionein-1 mRNA
Authors: Mickleburgh I. , Burtle B. , Nury D. , Chabanon H. , Chrzanowska-Lightowlers Z. , Hesketh J.E. 
Published: October 2004

mRNA localization provides a mechanism for localized protein synthesis. mRNAs encoding certain proteins, including c-MYC, c-FOS, MT-1 (Metallothionein-1) and vimentin, are localized around the nuclei of mammalian cells and are associated with the cytoskeleton. Targeting of these mRNAs to the perinuclear cytoplasm is mediated by elements within their 3′-UTRs (3′-untranslated regions), but many of the trans-acting proteins remain unidentified. UV cross-linking assays using radiolabelled transcripts indicated that a protein of approx. 50 kDa (from the Chinese-hamster ovary cell extracts) bound to the MT-1 3′-UTR sequence. Competition experiments using unlabelled mutant 3′-UTR RNAs revealed that the binding of this protein is specific to localization-positive mutants. Isolation of a 50 kDa protein was achieved by an RNA affinity-based method in which biotinylated MT-1 3′-UTR RNA was anchored to paramagnetic beads. Bound proteins were eluted and analysed by SDS/PAGE. The 50 kDa protein was extracted from the gel, subjected to trypsin digestion and identified by matrix-assisted laser-desorption/ionization–time-of-flight mass spectrometry as eukaryote elongation factor 1α.
The anaphase-promoting complex (APC): the sum of its parts?
Authors: Passmore L.A. 
Published: October 2004

The APC (anaphase-promoting complex) is a multisubunit E3 ubiquitin ligase that targets cell-cycle-related proteins for degradation by the 26 S proteasome. The APC contains at least 13 subunits and is regulated by the binding of co-activator proteins and by phosphorylation. It is not known why the APC contains 13 subunits when many other ubiquitin ligases are small single-subunit enzymes. In the present study, the structures and functions of individual APC subunits are discussed. By dissecting the roles of its parts, we hope to gain insight into the mechanism of the intact APC.
The effect of force on thermodynamics and kinetics: unfolding single RNA molecules
Authors: Tinoco I. , Collin D. , Li P.T.X. 
Published: October 2004

We have used laser tweezers to unfold single RNA molecules at room temperature and in physiological-type solvents. The forces necessary to unfold the RNAs are over the range 10–20 pN, forces that can be generated by cellular enzymes. The Gibbs free energy for the unfolding of TAR (transactivation-responsive) RNA from HIV was found to be increased after the addition of argininamide; the TAR hairpin was stabilized. The rate of unfolding was decreased and the rate of folding was increased by argininamide.
The integrity of cholesterol-enriched microdomains is essential for the constitutive high activity of protein kinase B in tumour cells
Authors: Elhyany S. , Assa-Kunik E. , Tsory S. , Muller T. , Fedida S. , Segal S. , Fishman D. 
Published: October 2004

A deregulated activity of PKB/Akt (where PKB stands for protein kinase B) renders tumour cells resistant to a variety of apoptosis-inducing stimuli. Elucidation of the mechanisms responsible for this deregulation is of prime importance for the development of novel anti-cancer drugs. Results of the present study demonstrate that the constitutive activity of PKB/Akt in B16BL6 melanoma cells depends on the integrity of cholesterol-enriched membrane microdomains, since the exposure of cells to cholesterol-depleting agents decreases the phosphorylation of this enzyme, with no change in its total protein level. Inhibitors of Hsp90 (heat-shock protein 90) decreased phosphorylation of PKB/Akt with a similar pattern. Dephosphorylation of the enzyme, as a consequence of raft disintegration, could be precluded by inhibition of serine/threonine (but not tyrosine) phosphatases. Our results imply that destabilization of lipid rafts seemingly affects the association of Hsp90 with the respective serine/threonine phosphatases, thereby increasing the accessibility to PKB/Akt to deactivating phosphatases. We have found recently that reconstituted expression of H-2K class I glycoproteins in class I-deficient B16BL6 cells also decreases the phosphorylation of PKB/Akt. Therefore it is possible that raft-associated regulation of this important enzyme involves both H-2K glycoproteins and Hsp90.
Hetero-oligomers of α2A-adrenergic and μ-opioid receptors do not lead to transactivation of G-proteins or altered endocytosis profiles
Authors: Zhang Y.Q. , Limbird L.E. 
Published: October 2004

Complexes of α2A-ARs (α2A-adrenergic receptors) and MORs (μ-opioid receptors), probably hetero-oligomers, were detected by co-immunoisolation after extraction from HEK-293 cells (human embryonic kidney 293 cells). Functional communication between these receptors is revealed by α2A-AR activation of a pertussis toxin-insensitive Giα subunit (termed as Gi1) when fused with the MOR and evaluated in membranes from pertussis toxin-treated cells. However, the α2A-AR does not require transactivation through MOR, since quantitatively indistinguishable results were observed in cells co-expressing α2A-AR and a fusion protein of Gi1 with the first transmembrane span of MOR (myc–MOR-TM1). Functional cross-talk among these α2A-AR–MOR complexes does not occur for internalization profiles; incubation with adrenaline (epinephrine) leads to endocytosis of α2A-AR but not MOR, while incubation with DAMGO ([D-Ala,NMe-Phe,Gly-ol]enkephalin) leads to endocytosis of MOR but not α2A-AR in cells co-expressing both the receptors. Hence, α2A-AR and MOR hetero-oligomers, although they occur, do not have an obligatory functional influence on one another in the paradigms studied.
Mitogenic stimulation of transcription by RNA polymerase III
Authors: Mauger E. , Scott P.H. 
Published: October 2004

Regulation of protein synthesis is an important aspect of growth control. RNA polymerase (pol) III plays a key role in this process by catalysing production of tRNA and 5 S rRNA. Growth factors trigger a rapid increase in pol III activity and this is essential for cell proliferation. The transcription factor TFIIIB plays a key role in controlling pol III activity and is a target for regulation by a number of mechanisms. This review will focus on how TFIIIB is targeted by these proteins in response to mitogen stimulation.
Dietary carotenoids, connexins and cancer: what is the connection?
Authors: Bertram J.S. 
Published: October 2004

Carotenoids and retinoids are chemically related; indeed a major source of vitamin A in humans occurs through enzymic cleavage of β-carotene. However, most dietary carotenoids cannot be converted into retinoids. Retinoids have demonstrated cancer-preventive activities in humans and experimental models; however, their toxicity has precluded wide-scale clinical use. In contrast, carotenoids are essentially non-toxic and their cancer-preventive activities, although strongly supported by epidemiological studies, have only been satisfactorily demonstrated in experimental systems. We have shown that in an experimental cell culture system consisting of carcinogen-treated 10T1/2 cells, both retinoids and all dietary carotenoids examined can reversibly inhibit neoplastic transformation in the post-initiation phase of carcinogenesis. This activity strongly correlates with their ability to increase gap junctional intercellular communication by up-regulating the expression of the gene CX43 (connexin43). Connexins comprise the structural unit of gap junctions, organelles which allow direct transfer of signals, nutrients and waste products between contacting cells. CX43 is the most widely expressed member of the gap junction family of genes, and we have demonstrated that its expression is strongly down-regulated in human cancers and in several premalignant conditions. When several human tumour cell lines were genetically engineered to conditionally express CX43 under the influence of a tetracycline promoter, their neoplastic phenotype was strongly attenuated. Specifically, induced cells were inhibited from growing in an anchorage-independent manner and, additionally, growth as xenografts in immunocompromised animals was also strongly attenuated. Growth inhibition in suspension was associated both with increased G1 cell-cycle arrest and with increased apoptosis. We propose a model whereby junctional communication allows the transfer of growth inhibitory signals from normal to neoplastic cells and that retinoids and carotenoids, by increasing signal transfer, act to prevent cancer.
Oxidant regulation of the bivalent cation transporter Nramp1
Authors: Yeung I.Y.L. , Phillips E. , Mann D.A. , Barton C.H. 
Published: October 2004

Nramp1 (murine natural resistance-associated macrophage protein 1 gene)/Slc11a1 (solute carrier family 11 member a1 gene) encodes a bivalent-metal/iron transporter that is expressed within late endosomes/lysosomes of macrophages. A functionally null Nramp1 allele that exhibits impaired bivalent cation transport enables excessive growth of intracellular pathogens. Iron is important for many cellular activities, including defence against pathogens; however, redox-active/free iron can participate in Fenton chemistry that generates reactive oxygen species. Using Raw264.7 cells, non-functional for Nramp1, and stable Nramp1 transfectants, we have examined the effects of impaired bivalent cation transport on macrophage function using glutathione depletion as OS (oxidant stress). Our results demonstrate that OS itself is a signal for increasing Nramp1 transcription and that Nramp1 expression protects against OS. We suggest that OS-mediated protection by Nramp1 function may arise from direct removal of redox-active bivalent cations from a cytosolic pool. We show that OS transcriptional responses are probably mediated by the Sp1 transcription factor.
Mass spectroscopic analysis of phosphatidylinositol synthesis using 6-deuteriated-myo-inositol: comparison of the molecular specificities and acyl remodelling mechanisms in mouse tissues and cultured cells
Authors: Postle A.D. , Dombrowsky H. , Clarke H. , Pynn C.J. , Koster G. , Hunt A.N. 
Published: October 2004

Mammalian cell PtdIns (phosphatidylinositol) in vivo is enriched in the sn-1-stearoyl 2-arachidonoyl species, the physiological precursor of phosphatidylinositol 4,5-bisphosphate. Mechanisms regulating this specificity are unclear but are typically lost for cells in culture. We used ESI-MS (tandem electrospray ionization-mass spectrometry) to determine the molecular species of PtdIns synthesized by mouse tissues in vivo compared with cultured cells in vitro. After incorporation of deuteriated myo-d6-inositol over 3 h, endogenous and newly synthesized PtdIns and lysoPtdIns species were quantified from precursor scans of m/z 241− and m/z 247− respectively. PtdIns was synthesized as a wide range of species irrespective of the final membrane composition. Analyses of isotope enrichments argued against acyl remodelling as the major regulatory mechanism: composition of the lysoPtdIns pool under all conditions reflected that of either endogenous or newly synthesized PtdIns and was always at equilibrium. The kinetics of PtdIns synthesis, together with the prolonged time scale required for achieving final equilibrium compositions suggest that selective transport between membranes and/or hydrolysis of selected molecular species are the most probable mechanisms regulating compositions of PtdIns and, ultimately, phosphatidylinositol 4,5-bisphosphate.
Lipidomic analysis of the molecular specificity of a cholinephosphotransferase in situ
Authors: Hunt A.N. , Fenn H.C. , Clark G.T. , Wright M.M. , Postle A.D. , McMaster C.R. 
Published: October 2004

Dynamic lipidomics using ESI–MS (tandem electrospray ionization mass spectrometry) of 9-deuterated choline (choline-d9) incorporation into mammalian cell PtdCho (phosphatidylcholine) permits assessment of the molecular specificity of synthesis. Bulk cell PtdCho synthesis occurs in spatially distinct locations, using separate CPTs (1,2 diacylglycerol CDP:choline cholinephosphotransferases). We assessed whether in vitro molecular selectivity of DAG (diacylglycerol) incorporation between CPTs is manifest in situ, by monitoring choline-d9 incorporation into PtdCho and lyso-PtdCho molecular species over 3 h in control cells and in CHO-K1 cells overexpressing hCEPT1. Compared with controls, the basal molecular species composition of hCEPT1 overexpressors was significantly enriched in arachidonate. This was not due to net accretion of cellular PtdCho arguing against effects of inadequate unsaturated PtdCho degradation or remodelling. Rather, time-course analyses of PtdCho and lyso-PtdCho pools showed that both arachidonate-containing DAG incorporation and turnover of PtdCho is increased in hCEPT1 overexpressors. Increased choline-d9 incorporation into arachidonyl lyso-PtdCho shows that both phospholipase A1- and A2-mediated turnover is involved. Spatially distinct molecular specificity of DAG incorporation into cellular PtdCho at the level of hCEPT1 exists in situ.