bluuebunny/crossref_metadata_2025 huggingface dataset:
Phorbol ester‐induced cell death in PC‐12 cells overexpressing Bcl‐2 is dependent on the time at which cells are treated
Authors: Hahn Michael A. , Mayne George C.
Published: June 2004

The aim of the present study was to investigate the involvement of PKC in Bcl‐2 protection against serum withdrawal‐induced apoptosis in PC‐12 cells. Human Bcl‐2 was overexpressed in PC‐12 cells and was found to totally inhibit serum withdrawal‐induced apoptosis. 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) could induce cell death in PC‐12 cells that overexpressed Bcl‐2, implicating protein kinase C (PKC) in Bcl‐2 protection. However, TPA‐induced cell death did not involve caspase‐3 activation or DNA degradation, suggesting that Bcl‐2 was still inhibiting these processes and that TPA was mediating cell death either downstream of Bcl‐2 or via independent signalling pathways. High cytosolic and particulate protein levels of PKC δ were correlated with TPA‐induced cell death suggesting that PKC δ positively regulated this cell death. However, substantial down‐regulation of PKC by prolonged exposure to TPA did not reduce the frequency of TPA‐induced cell death, raising the possibility that PKC δ did not regulate cell death alone. Surprisingly, TPA‐induced cell death was dependent on the time at which cells were treated, suggesting that cells were changing with time. Supporting this idea, the cytosolic and particulate protein levels of PKC δ and ∍ were found to change with time, and may account for the time‐dependent manner in which TPA induced cell death. This is the first report to show that sensitivity to drug induced cell death in a cultured cell line changes with time. Experimental and theoretical evidence suggests that many cellular constituents exhibit temporal variations, oscillations or rhythms due to feedback regulation. We believe that investigation of these temporal changes, how they alter cell function with time and how they might be manipulated in single cells as well as across cellular populations is paramount in furthering our understanding of cellular behaviour.
Protection against MPP+ neurotoxicity in cerebellar granule cells by antioxidants
Authors: González‐Polo Rosa A. , Soler Germán , Rodrıguezmartın Andrea , Morán Jose M. , Fuentes José M.
Published: June 2004

The neuropathology associated with Parkinson's disease (PD) is thought to involve excessive production of free radicals, dopamine autoxidation, defects in glutathione peroxidase expression, attenuated levels of reduced glutathione, altered calcium homeostasis, excitotoxicity and genetic defects in mitochondrial complex I activity. While the neurotoxic mechanisms are vastly different for excitotoxins and 1‐methyl‐4‐phenylpyridinium ion (MPP+), both are thought to involve free radical production, compromised mitochondrial activity and excessive lipid peroxidation. We show here that the levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) increased significantly after treatment of cultured cerebellar granule cells (CGCs) with 50 μM MPP+. Co‐treatment with antioxidants such as ascorbate (ASC), catalase, α‐tocopherol (α‐TOH), coenzyme Q10 (CoQ10) or superoxide dismutase (SOD) rescued the cells from MPP+‐induced death. MPP+‐induced cell death was also abolished by co‐treatment with nitric oxide synthase (NOS) inhibitors such as 7‐nitroindazole (7‐NI), 2‐ethyl‐2‐thiopseudourea hydrobromide (EPTU) or S‐methylisothiourea sulphate (MPTU). We also tested the protective effects of an iron chelator (deferoxamine mesylate, DFx) and a peroxynitrite scavenger (FeTTPS) and the results lend further support to the view that the free radical cytotoxicity plays an essential role in MPP+‐induced death in primary cultures of CGC.
Analysis of the contraction of an organelle using its birefringency: the R‐fibre of the Ceratium (Dinoflagellate) flagellum*
Authors: Sato Hidemi , Greuet Claude , Cachon Monique , Cosson Jacky
Published: June 2004

Some organelles responsible for contraction consist of bundles of 2–4 nm filaments called nanofilaments. Such organelles are present in the longitudinal flagellum of Ceratium (Dinoflagellate): the R‐fibre is the motor system for contraction and parallels the axoneme, which is responsible for wave generation. We used a highly sensitive polarization microscope developed by one of the authors to measure the birefringence of these nanofilament bundles during contraction in vivo. Our results show that the R‐fibre gives a highly birefringent signal, retarding the polarization to much the same extent irrespective of the direction of polarization. By rotating the axis of the microscope compensator we confirmed that the birefringence is positive, suggesting that the bundles run parallel to the longitudinal axis of the flagellum. Conversely, when the compensator was rotated contrary to the direction of retardation, the bundle appeared dark (except when the organelle was in a fully contracted state). Experiments performed on detergent‐treated and ATP‐reactivated flagella show that a portion of the flagella regained activity with the addition of ATP in the presence of low Ca2+ concentrations. This demonstrates the ability to reactivate flagellar motility after permeabilization and that axonemal microtubules were not responsible for the strong flagellar birefringence. Combined with complementary data from DIC microscopy of demembranated flagella and electron microscopy, these findings have led to the development of a model of the R‐fibre and a comparison with other types of birefringent nanofilament bundles, such as the myoneme of Acantharia.
Changes in elemental concentrations in LNCaP cells are associated with a protective effect of neuropeptides on etoposide‐induced apoptosis
Authors: Salido M. , Vilches J. , Roomans G.M
Published: May 2004

One of the mechanisms that has been put forward for the development of the androgen‐resistant status is neuroendocrine differentiation. Neuroendocrine cells secrete neuropeptides that may represent one of the possible molecular bases by which hormone‐dependent prostate cancer cells could escape treatment. LNCaP prostate cancer cells were treated with either etoposide or neuropeptides. Morphological changes related to apoptosis and cell viability were assessed. Changes in intracellular ion content were quantitatively analyzed by electron probe X‐ray microanalysis. Etoposide treatment consistently induces a decrease in K and an increase in Na, which are inhibited by bombesin or calcitonin. The Na/K ratio increased markedly after exposure to etoposide, and both bombesin and calcitonin blocked this increase. Etoposide also caused changes in the intracellular P and S concentrations that to a large extent could be blocked by neuropeptides. These results support the hypothesis that neuropeptides confer anti‐apoptotic capabilities onto non‐neuroendocrine cells in close proximity to neuroendocrine cells.
ERK signaling pathway is differentially involved in erythroid differentiation of K562 cells depending on time and the inducing agent
Authors: Woessmann Willi , Zwanzger Dorothea , Borkhardt Arndt
Published: June 2004

K562 cells can be induced to differentiate along the erythroid lineage by a variety of chemical compounds, including hemin, butyrate, cisplatin and ara‐C. Differential signaling through MAP kinases has been suggested to be involved in this differentiation process. We have investigated the involvement of ERK activation/inhibition in hemin‐, butyrate‐, cisplatin‐ and ara‐C‐induced erythroid differentiation using the K562 cell line. ERK activity decreased for 2–4 h after administration of either inducing agent. ERK was then activated by hemin and cisplatin, while ERK phosphorylation remained decreased during incubation with butyrate and ara‐C. There was no activation of JNK or p38. The MEK‐1 inhibitors UO126 or PD98059 induced erythroid differentiation in K562 cells and acted additively with butyrate. Inhibition of MEK‐1 reduced the hemoglobin accumulation by hemin and cisplatin; erythroid differentiation by ara‐C was unchanged. The results suggest that inhibition of signaling through ERK in K562 cells may be needed to enter the erythroid differentiation process, while after initiation both activation and inhibition of signaling through ERK enhance erythroid differentiation, which, however, is dependent on the inducing compound.
A case of social phobia and avoidant personality disorder with erectile dysfunction successfully treated with venlafaxine and add-on reboxetine
Authors: Pacchiarotti Isabella , Manfredi Giovanni , Kotzalidis Giorgio D. , Ruberto Amedeo , Tatarelli Roberto , Girardi Paolo
Published: May 2004

A 25-year-old man with DSM-IV-TR Axis I social phobia and Axis II avoidant personality disorder and erectile dysfunction, presenting with depression, anxiety and insomnia, responded partially to extended release oral venlafaxine (75 mg/die for 6 weeks), but developed side effects and worsening symptoms when dose was increased to 150 mg/die; he responded to a combination of 75 mg/die venlafaxine and 4 mg/die reboxetine and improved on most of his symptoms.
Language bias in neuroscience—is the Tower of Babel located in Germany?
Authors: Heres S. , Wagenpfeil S. , Hamann J. , Kissling W. , Leucht S.
Published: May 2004

In internal medicine German authors tend to publish randomized controlled trials (RCTs) with non-significant findings in German journals, RCTs with significant findings in international journals. In the neurosciences a similar trend was seen but the findings were not statistically significant. The reason for this inconclusive finding might be the low number of RCTs published in German.
Binding site for the C‐domain of insulin‐like growth factor (IGF) binding protein‐6 on IGF‐II; implications for inhibition of IGF actions
Authors: Headey Stephen J , Keizer David W , Yao Shenggen , Wallace John C , Bach Leon A , Norton Raymond S
Published: May 2004

Insulin‐like growth factors (IGFs) are important mediators of growth and IGF‐binding proteins (IGFBPs) 1–6 regulate IGF actions. As IGFBP C‐terminal domains contribute to high‐affinity IGF binding, we have defined the binding site for the C‐domain of IGFBP‐6 on IGF‐II using NMR. This site lies adjacent to and between the binding sites for the IGFBP N‐domain and IGF‐I receptor (IGFIR), which have previously been found on opposite sides of the IGF molecule. The C‐domain is therefore likely to interfere with IGF binding to the IGFIR, providing a structural basis for the potent inhibitory effects of intact IGFBPs on IGF actions.
Aminoacylase 1 is a sphingosine kinase 1‐interacting protein
Authors: Maceyka Michael , Nava Victor E. , Milstien Sheldon , Spiegel Sarah
Published: May 2004

Sphingosine kinase type 1 (SphK1) and its product sphingosine‐1‐phosphate have been shown to promote cell growth and inhibit apoptosis of tumor cells. In an effort to further understand the regulation of SphK1, we used a yeast two‐hybrid screen to find SphK1‐interacting proteins. One of these was identified as aminoacylase 1 (Acy1), a metalloenzyme that removes amide‐linked acyl groups from amino acids and may play a role in regulating responses to oxidative stress. Both the C‐terminal fragment found in the two‐hybrid screen and full‐length Acy1 co‐immunoprecipitate with SphK1. Though both C‐terminal and full‐length proteins slightly reduce SphK1 activity measured in vitro, the C‐terminal fragment inhibits while full‐length Acy1 potentiates the effects of SphK1 on proliferation and apoptosis. Interestingly, Acy1 induces redistribution of SphK1 as observed by immunocytochemistry and subcellular fractionation. Collectively, our data suggest that Acy1 physically interacts with SphK1 and may influence its physiological functions.
Proteolytic cleavage of platelet endothelial cell adhesion molecule‐1 (PECAM‐1/CD31) is regulated by a calmodulin‐binding motif
Authors: Wong Mae-Xhum , Harbour Stacey N , Wee Janet L , Lau Lai-Man , Andrews Robert K , Jackson Denise E
Published: May 2004

Homophilic engagement of platelet endothelial cell adhesion molecule‐1 (PECAM‐1/CD31) induces ‘outside‐in’ signal transduction that results in phosphorylation events and recruitment and activation of signalling molecules. The formation of signalling scaffolds with PECAM‐1 are important signalling events that modulate platelet secretion, aggregation and platelet thrombus formation. In this study, we describe a novel interaction between PECAM‐1 and cytosolic calmodulin (CaM) in platelets. Reciprocal co‐immunoprecipitation studies revealed that cytosolic CaM is constitutively associated with PECAM‐1 in resting, thrombin activated and aggregated human platelets. Our studies demonstrate that CaM directly interacts with a PECAM‐1 peptide (594–604) C595A containing the sequences 594KAFYLRKAKAK604. This CaM:PECAM‐1 interaction has a threefold higher affinity than CaM:GPVI interaction. It is potentiated by the addition of calcium ions, and dissociated by the CaM inhibitor, trifluoperazine. Treatment of platelets with CaM inhibitors triggers cleavage of PECAM‐1 in a time‐ and dose‐dependent manner. Furthermore, this membrane proximal portion of PECAM‐1 is conserved across mammalian species and the helical representation of basic/hydrophobic residues reveals a charge distribution analogous to other CaM‐binding motifs in other proteins. Taken together, these results suggest that this highly charged cluster of amino acids in the PECAM‐1 cytoplasmic domain directly interacts with CaM and this novel interaction appears to regulate cleavage of PECAM‐1.
Kinetic evidence related to substrate‐assisted catalysis of family 18 chitinases
Authors: Honda Yuji , Kitaoka Motomitsu , Hayashi Kiyoshi
Published: May 2004

The hydrolytic reaction of family 18 chitinase has been considered to occur via substrate assisted catalysis. To kinetically investigate the enzyme reaction mechanism, we synthesized compounds designed to reduce the polarization of the carbonyl in N‐acetyl group, GlcNAc‐GlcN(TFA)‐UMB (2) and GlcNAc‐GlcN(TAc)‐UMB (3). Kinetic parameters in the hydrolysis of these compounds by chitinase A from Serratia marcescens (ChiA) were compared with those from the hydrolysis of (GlcNAc)2‐UMB (1). The k
cat of 2 was 3.4% of 1, but the K
m of 2 was 10‐fold that of 1. In contrast, the k
cat of 3 was only 0.3% of that of 1, and the two reactions had an identical K
m. The drastic decreases in k
cat were probably due to the weak nucleophilic activity of the C2‐N‐trifluoroacetamide and N‐thioacetamide groups at reducing ends of compounds 2 and 3, respectively. These results indicate that the anchimeric assistance of the C2 N‐acetamide group at GlcNAc plays a key role in the hydrolytic reactions catalyzed by family 18 chitinases.
Heme environment in aldoxime dehydratase involved in carbon–nitrogen triple bond synthesis
Authors: Oinuma Ken-Ichi , Ohta Takehiro , Konishi Kazunobu , Hashimoto Yoshiteru , Higashibata Hiroki , Kitagawa Teizo , Kobayashi Michihiko
Published: May 2004

Resonance Raman spectra have been measured to characterize the heme environment in aldoxime dehydratase (OxdA), a novel hemoprotein, which catalyzes the dehydration of aldoxime into nitrile. The spectra showed that the ferric heme in the enzyme is six‐coordinate low spin, whereas the ferrous heme is five‐coordinate high spin. We assign a prominent vibration that occurs at 226 cm−1 in the ferrous enzyme to the Fe‐proximal histidine stretching vibration. In the CO‐bound form of OxdA, the correlation between the Fe–CO stretching (512 cm−1) and C–O stretching (1950 cm−1) frequencies also supports our assignment of proximal histidine coordination.
Protein kinase A phosphorylates serine 267 in the homeodomain of engrailed‐2 leading to decreased DNA binding
Authors: Hjerrild Majbrit , Stensballe Allan , Jensen Ole N , Gammeltoft Steen , Rasmussen Thomas E
Published: May 2004

Engrailed‐2 (En‐2) belongs to an evolutionarily conserved family of DNA binding homeodomain‐containing proteins that are expressed in mammalian brain during development. Here, we demonstrate that serine 267 in the homeodomain of En‐2 is phosphorylated by protein kinase A (PKA) in forskolin‐treated COS‐7 cells. Furthermore, we analyze the physiological function of En‐2 phosphorylation by PKA. The nuclear localization of En‐2 is not influenced by the phosphorylation of serine 267. However, substitution of serine 267 with alanine resulted in increased binding of En‐2 to DNA, while replacing serine 267 with glutamic acid resulted in decreased En‐2 DNA binding. These results suggest that the transcriptional activity of En‐2 is regulated by PKA.
Identification of the heat shock protein 60 epitope involved in receptor binding on macrophages
Authors: Habich Christiane , Kempe Karina , Burkart Volker , van der Zee Ruurd , Lillicrap Mark , Gaston Hill , Kolb Hubert
Published: May 2004

In the present study, we identified the human heat shock protein 60 (HSP60) epitope responsible for binding to macrophages. Studies using overlapping 15‐ and 20‐mer peptides of the human HSP60 sequence to compete with binding of HSP60 to macrophages indicated that surface binding was accounted for by the region aa481–500. Deletion mutants of HSP60, lacking the N‐terminal 137, 243 or 359 amino acids, strongly inhibited HSP60 binding to macrophages. Monoclonal antibodies addressing regions aa1–200, aa335–366 or aa383–447 did not block HSP60 binding. We conclude that a single C‐terminal region, aa481–500, accounts for the binding of HSP60 to macrophages.
The G‐protein‐coupled CCK2 receptor associates with phospholipase Cγ1
Authors: Arnould Marika , Tassa Amina , Ferrand Audrey , Archer Elodie , Estève Jean-Pierre , Pénalba Virginie , Portolan Ghislaine , Escherich Achim , Moroder Luis , Fourmy Daniel , Seva Catherine , Dufresne Marlène
Published: May 2004

In ElasCCK2 transgenic mice expressing cholecystokinin (CCK2) receptor in acinar cells, pancreatic phenotypic alterations and preneoplastic lesions are observed. We determined whether activation of phospholipase C gamma1 (PLCγ1), known to contribute to the tumorigenesis pathophysiology, could take place as a new signaling pathway induced by the CCK2 receptor. Overexpression and activation of the PLCγ1 in response to gastrin was observed in acinar cells. The possibility that the C‐terminal tyrosine 438 of the CCK2 receptor associates with the SH2 domains of PLCγ1 was examined. A specific interaction was demonstrated using surface plasmon resonance, confirmed in a cellular system and by molecular modeling.
Biochemical and cell biological characterization of a mammalian septin, Sept11
Authors: Hanai Nobuhiro , Nagata Koh-ichi , Kawajiri Aie , Shiromizu Takashi , Saitoh Noriko , Hasegawa Yasuhisa , Murakami Shingo , Inagaki Masaki
Published: June 2004

Septins are a family of conserved cytoskeletal GTPases implicated in a variety of cellular functions such as cytokinesis and vesicle trafficking. Here, we report identification of an yet uncharacterized septin, Sept11, in septin complexes purified from porcine brain. The transcripts were detected in all tested tissues except leukocytes. A Sept11 mutant with apparently reduced GTPase activity did not form filaments in the transient expression system using COS7 cells. By Western blot analysis using a specific antibody, Sept11 was detected in various cell lines as well as brain tissues. Septin complexes immunoisolated from porcine brain with anti‐Sept9 and anti‐Sept11 antibodies were found to contain different Sept9 isoforms based on SDS–PAGE analyses followed by silver‐staining and Western blotting. Immunofluorescent study revealed cell type‐dependent intracellular localization of the protein; Sept11 was colocalized dominantly with microtubules and actin stress fibers in HMEC cells and REF52 cells, respectively, and their filamentous distribution was dependent on the cytoskeleton structures with which the protein is colocalized. Sept11 partially colocalized with stress fibers and microtubules in HeLa cells.
Potassium channel openers are uncoupling protonophores: implication in cardioprotection
Authors: Holmuhamedov Ekhson L , Jahangir Arshad , Oberlin Andrew , Komarov Alexander , Colombini Marco , Terzic Andre
Published: June 2004

Excessive build‐up of mitochondrial protonic potential is harmful to cellular homeostasis, and modulation of inner membrane permeability a proposed countermeasure. Here, we demonstrate that structurally distinct potassium channel openers, diazoxide and pinacidil, facilitated transmembrane proton translocation generating H+‐selective current through planar phospholipid membrane. Both openers depolarized mitochondria, activated state 4 respiration and reduced oxidative phosphorylation, recapitulating the signature of mitochondrial uncoupling. This effect was maintained in K+‐free conditions and shared with the prototypic protonophore 2,4‐dinitrophenol. Diazoxide, pinacidil and 2,4‐dinitrophenol, but not 2,4‐dinitrotoluene lacking protonophoric properties, preserved functional recovery of ischemic heart. The identified protonophoric property of potassium channel openers, thus, implicates a previously unrecognized component in their mechanism of cardioprotection.
Metabolism and chemical composition of mesopelagic ostracods in the western North Pacific Ocean
Authors: Kaeriyama Hideki , Ikeda Tsutomu
Published: May 2004

Oxygen consumption rates and bodily elemental composition (carbon (C) and nitrogen (N)) were determined on three dominant ostracods (Discoconchoecia pseudodiscophora, Orthoconchoecia haddoni, and Metaconchoecia skogsbergi) from the mesopelagic zone of the Oyashio region. Specific oxygen consumption rates of the three species at near in situ temperature (3°C) were similar (0.39 μl O2 mg DW−1 h−1), but bodily C composition and C:N ratios of D. pseudodiscophora were significantly higher than those of the other two species. Metabolic comparison in terms of “daily body C loss” or “adjusted metabolic rate” revealed that metabolic rates of the ostracods are 0.3–0.4 times those of other zooplankton at comparable temperature conditions. The present results were combined with standing stock data of each ostracod in the Oyashio region to estimate their POC ingestion. Our calculation indicates annual ingestion by the ostracods to be 875 mgC m−2 yr−1, which equates to 3.7% of annual POC flux reaching 200–600-m depth (mid-point: 400-m depth) in this region.
Comparison of biomass and size spectra derived from optical plankton counter data and net samples: application to the assessment of mesoplankton distribution along the Northwest and North Iberian Shelf
Authors: Nogueira Enrique , González-Nuevo Gonzalo , Bode Antonio , Varela Manuel , Morán Xosé Anxelu G , Valdés Luis
Published: May 2004

Data from vertical net hauls and from a submersible optical plankton counter (OPC) were compared in terms of biomass and slope of the normalized biomass–size spectra (NB–SS), a proxy for the size structure of the community. The relationship between the estimates of biomass in the overlapping range sampled by both methods (0.2–2 mm equivalent spherical diameter (ESD)) was linear and not significantly different to 1 (BOPC:BNET=1.1±0.1, r2=0.84). However, the relationship varied depending on the size fraction considered; the ratio BOPC:BNET was 0.10±0.04 (r2=0.30), 0.8±0.2 (r2=0.66), and 2.4±0.5 (r2=0.64) for the size fractions 0.2–0.5, 0.5–1, and 1–2 mm ESD, respectively. The discrepancies between methods were presumably due to the combined effect of the limitations of the instrument in the lower detection limit and the errors in the volume of water sampled by the net for the smallest size fraction, and to net avoidance enhanced by clogging for the largest size fraction. The agreement between methods improved when the NB–SS of the different data sets were compared. The slope (b=−1.1) and the intercept (a=14.6) of the NB–SS integrated across stations were not significantly different (Student's t-test) for the linear model fitted to net samples, OPC data, or pooled data from both methods. Station by station, the slopes of the NB–SS from the net (bNET) and the OPC (bOPC) were not significantly different in 61% of the stations. This percentage increased to 78% when the comparison was limited to the mesoplankton size range. As an example of the applicability of the OPC, we showed the distribution of mesoplankton biomass and size structure along the NW and N Iberian Shelf during the winter–spring transition of 2002 and its relationship with the hydrographic scenario.
Life-history strategies of calanoid congeners under two different climate regimes: a comparison
Authors: Halsband-Lenk Claudia , Carlotti François , Greve Wulf
Published: May 2004

To evaluate the relationship between different environmental temperature regimes and life-history traits of key planktonic taxa, the life cycles of congener pairs of Temora and Centropages species at two sites, a cold-temperate shelf sea (Helgoland Island, North Sea) and a warm-temperate oceanic site (Bay of Villefranche, Mediterranean) were compared in a multi-annual time-series. In an attempt to assemble a variety of parameters – some detailed, others sporadically measured – a synthesis of the life cycle is presented for each population. Although closely related, congeners showed distinct temperature preferences and specific adaptations of their life cycles to temperature regime. On the other hand, co-existing species such as T. longicornis and C. hamatus in the North Sea showed some analogous life-history traits. C. typicus occupied an intermediate position and was able to tolerate both temperature regimes by shifting its reproductive period between seasons. We point out interannual and inter-site variability in the populations investigated and identify the unsolved questions in regard to the seasonal dynamics of these species that require verification.
Carbon cycling through the pelagic foodweb in the northern Humboldt Current off Chile (23°S)
Authors: González H.E. , Giesecke R. , Vargas C.A. , Pavez M. , Iriarte J. , Santibáñez P. , Castro L. , Escribano R. , Pagès F.
Published: May 2004

The structure of the zooplankton foodweb and their dominant carbon fluxes were studied in the upwelling system off northern Chile (Mejillones Bay; 23°S) between October 2000 and December 2002. High primary production (PP) rates (1–8 gC m−2 d−1) were mostly due to the net-phytoplankton size fraction (>23 μm). High PP has been traditionally associated with the wind-driven upwelling fertilizing effect of equatorial subsurface waters, which favour development of a short food chain dominated by a few small clupeiform fish species. The objective of the present work was to study the trophic carbon flow through the first step of this “classical chain” (from phytoplankton to primary consumers such as copepods and euphausiids) and the carbon flow towards the gelatinous web composed of both filter-feeding and carnivorous zooplankton. To accomplish this objective, feeding experiments with copepods, appendicularians, ctenophores, and chaetognaths were conducted using naturally occurring plankton prey assemblages. Throughout the study, the total carbon ingestion rates showed that the dominant appendicularian species and small copepods consumed an average of 7 and 5 μgC ind−1 d−1, respectively. In addition, copepods ingested particles mainly in the size range of nano- and microplankton, whereas appendicularians ingested in the range of pico- and nanoplankton. Small copepods and appendicularians removed a small fraction of total daily PP (range 6–11%). However, when the pico- + nanoplankton fractions were the major contributors to total PP (oligotrophic conditions), grazing by small copepods increased markedly to 86% of total PP. Under these more oligotrophic conditions, the euphausiids grazing increased as well, but only reached values lower than 5% of total PP. During this study, chaetognaths and ctenophores ingested an average of 1 and 14 copepods ind−1 d−1, respectively. In terms of biomass consumed, the potential impact of carnivorous gelatinous zooplankton on the small-size copepod community (preferred prey) was important (2–12% of biomass removed daily). However, their impact produced more significant results on copepod abundance (up to 33%), which suggests that carnivorous gelatinous zooplankton may even modulate (control) the abundance of some species as well as the size structure of the copepod community.
Hydrographical characteristics and zooplankton distribution in the Mallorca channel (Western Mediterranean): spring 2001
Authors: Fernández de Puelles M. Luz , Valencia Joaquín , Jansá Javier , Morillas Ana
Published: May 2004

The distribution of zooplankton in the upper 100 m of the Mallorca channel (Balearic Sea) was investigated during the spring of 2001 and related to the main hydrographic parameters. Synoptic satellite images were examined and 29 stations were sampled by means of oblique hauls. The sea surface temperature, salinity, and chlorophyll a in the channel show the existence of a hydrological front related to the composition of phyto- and zooplankton. The main zooplankton groups revealed a horizontal distribution pattern related to the hydrographic features of the area. The highest zooplankton abundance, mainly due to copepods (78% of the total zooplankton), was found where the coolest and more saline waters were observed, i.e. in the northern part of the channel. The lowest abundance, mainly represented by siphonophores, chaetognaths, and doliolids, was in the south in the warmer and less saline waters, indicating the input of Atlantic waters into the channel. The spatial distribution of the main species and zooplankton groups was also examined in relation to the frontal system, suggesting their function as biological indicators of the upper water hydrography in the Balearic Sea (Western Mediterranean).
Differences in the regulation of BDNF and NGF synthesis in cultured neonatal rat astrocytes
Authors: Miklič Špela , Jurič Damijana Mojca , Čaman‐Kržan Marija
Published: June 2004

Using a new brain‐derived neurotrophic factor (BDNF) specific enzyme‐immunoassay, we determined the basal cellular content of BDNF protein in neonatal rat astrocytes in primary culture, thus confirming the ability of astrocytes to synthesize BDNF in addition to nerve growth factor (NGF). We subsequently monitored the influence of different pharmacological agents: neurotransmitter receptor agonists, cytokines, and second messenger up‐regulators, on the synthesis of BDNF and NGF. Marked differences in the regulation of their synthesis by the above pharmacological agents were observed in our study.

The basal cellular levels of BDNF protein in cultured neonatal rat cortical and cerebellar astrocytes were 15.9±0.3 and 18.7±0.4 pg BDNF/mg cell protein, respectively, and differ significantly between astrocytes from different brain regions, whereas NGF levels were the same (16.1±0.3 and 16.2±0.7 pg NGF/mg cell protein, respectively). Screening different neurotransmitter systems for their influence on BDNF and NGF synthesis in cortical astrocytes revealed that dopamine (0.15 mM) is a potent up‐regulator of BDNF protein synthesis in astrocytes, while kainic acid (50 μM) and histamine (1 μM) did not raise the cellular level of BDNF protein. Dopamine had no influence on NGF synthesis, while kainic acid caused minor, and histamine marked, elevation of NGF cellular content. Tumor necrosis factor‐α (30 ng/ml) and interleukin‐1β (10 U/ml) treatments did not influence BDNF synthesis, whereas they markedly increased NGF protein cellular level. We also confirmed (using forskolin (20 μM) and phorbol 12‐myristate 13‐acetate (TPA) (100 nM)) that adenylate cyclase and protein kinase C participate in the downstream signaling responsible for the stimulation of BDNF synthesis, whereas in the regulation of NGF synthesis only the participation of protein kinase C was confirmed.

Our results indicate that astrocyte‐derived neurotrophins could play a role in distinct brain functions under physiological conditions and in the pathogenesis as well as possible treatment of different neurodegenerative disorders.
Postpartum hemorrhage in developing countries: is the public health community using the right tools?
Authors: Tsu V.D. , Langer A. , Aldrich T.
Published: May 2004

Objectives: To identify new and underutilized technologies that may assist in reducing maternal mortality due to obstetric hemorrhage. Methods: Review of published and unpublished literature, including systematic reviews of randomized trials and individual clinical studies. Results: Hemorrhage, primarily postpartum, accounts for approximately 25% of maternal deaths globally. Uterotonic drugs offer great promise for both prevention and management of postpartum hemorrhage (PPH). Other technologies—such as anti‐shock garments, umbilical vein injection of oxytocin, and simple anemia detection methods—represent potential new opportunities to reduce PPH‐related mortality. Conclusions: Clinical and operational research is needed to answer remaining questions about misoprostol, the anti‐shock garment, and umbilical vein injection of oxytocin for retained placenta. Efforts are needed to ensure the availability of technologies with proven value, such as oxytocin in Uniject™ prefilled injection devices. Equally important, technologies and techniques with proven efficacy—such as active management of third‐stage labor and aortic compression—must be translated into general use by disseminating the evidence for them, incorporating them into national guidelines and training curricula, and ensuring the availability of supportive supplies and equipment.
Improving technologies to reduce abortion‐related morbidity and mortality
Authors: Rogo K.
Published: May 2004

This article reviews the technologies used to diagnose pregnancy and manage abortion in developing countries. The author discusses methods of diagnosing pregnancy—including physical examination, laboratory and home testing, and ultrasound—as well as methods for performing safe abortions. Due to manual vacuum aspiration (MVA) advances, vacuum aspiration has become safer and more feasible in low‐resource settings. The discussion of medical abortion includes the advantages and limitations of mifepristone, misoprostol‐only regimens, methotrexate, and other methods. The author stresses the importance of post‐abortion care and post‐abortion contraception and, in the conclusion, identifies six areas in which technology can reduce abortion‐related morbidity and mortality: pregnancy prevention, early diagnosis of pregnancy, accurate assessment of gestation, standardization and supply of MVA technology, and simple and affordable regimens for medical abortion.
New and underutilized technologies to reduce maternal mortality: call to action from a Bellagio workshop
Authors: Tsu V.D , Shane B
Published: May 2004

Little progress has been made in preventing the more than 500 000 maternal deaths that occur each year. Many new and underutilized technologies can be used to reduce these deaths. In July 2003, maternal health experts from around the world gathered in Bellagio, Italy, to develop a set of priority actions for reducing maternal mortality using proven and promising technologies. To reduce maternal mortality, immediate efforts are needed to accelerate the appropriate use of technologies and to reduce their inequitable distribution. Organizations are called on to commit the necessary human and financial resources to evaluate and document the effectiveness of promising technologies and to scale up and put proven technologies into widespread use to save women's lives.
Methodological and technical issues related to the diagnosis, screening, prevention, and treatment of pre‐eclampsia and eclampsia
Authors: Villar J , Say L , Shennan A , Lindheimer M , Duley L , Conde‐Agudelo A , Merialdi M
Published: May 2004

In contrast with advances made in treating or eliminating many other serious disorders, severe morbidity and mortality associated with pre‐eclampsia/eclampsia remain among the leading problems that threaten safe motherhood, particularly in developing countries. This article reviews technical issues related to diagnosis, screening, prevention, and treatment of pre‐eclampsia and identifies corresponding needs. The authors stress the lack of standardized definitions of pre‐eclampsia and eclampsia and discuss problems in blood‐pressure measurements and assessment of urinary protein. They summarize the evidence for prevention strategies and screening tests for early detection. For treatment, magnesium sulfate has been proven effective, but not widely used. The authors outline priorities for narrowing the identified gaps and emphasize the need for coordinated efforts to reduce the morbidity and mortality due to pre‐eclampsia/eclampsia. They conclude that the mystery of this disease must be resolved to achieve primary prevention of it.
Asymptomatic double ureteral stricture in an 8-month-old Maine Coon cat: An imaging-based case report
Authors: Zotti Alessandro , Poser Helen , Chiavegato David
Published: June 2004

Congenital ureteral strictures are rare both in human and veterinary medicine. While the diagnosis is generally made after a symptomatic or febrile urinary tract infection, we report here a case in which this condition represented an incidental finding during routine ultrasonography. To the best of the authors' knowledge imaging findings of a double monolateral ureteral stricture have not previously been reported.
Dupuytren’s Disease on the Radial Aspect of the Hand: Report on 135 Hands in Japanese Patients
Authors: ABE Y. , ROKKAKU T. , OFUCHI S. , TOKUNAGA S. , TAKAHASHI K. , MORIYA H.
Published: May 2004

We studied 135 hands in 77 Japanese patients to assess the frequency of radial involvement and its association with recurrence and the Dupuytren’s diathesis. The radial aspect of the hand was affected in 22% of the hands. Diseased cords were observed in ten patients who underwent surgery on the radial aspect of the hand. Longitudinal cords on the radial side of thenar eminence and distal transverse interdigital cords were common. The radial aspect of the hand was the most common site of disease extension, though recurrence never occurred after excision of a radial lesion. Ectopic lesions, bilateral hand involvement, and recurrence were significantly more frequent in patients with the radial side involvement. Thus the results of this study suggest that radial side disease is associated with the Dupuytren’s diathesis and is a risk factor of recurrence.
Reducing the Pain Associated with Local Anaesthetic Infiltration for open Carpal Tunnel Decompression
Authors: VOSSINAKIS I. C. , STAVROULAKI P. , PALEOCHORLIDIS I. , BADRAS L. S.
Published: May 2004

This prospective, randomized study assessed the effectiveness of buffering lidocaine with sodium bicarbonate for reducing the pain associated with local anaesthetic infiltration for open carpal tunnel decompression. Twenty-one patients undergoing bilateral open carpal tunnel decompression received, in a randomized manner, lidocaine 1% with adrenaline (1:200,000) in one hand and the same local anaesthetic buffered with 8.4% NaHCO3 at a 5:1 ratio in the other hand. Pain, especially its burning element, was evaluated on a visual analogue scale and was significantly reduced with the buffered solution. The buffering was effective for all patients and no adverse effects were noted. This is a safe, easy and quick method for making open carpal tunnel surgery less uncomfortable to patients.
Prostacyclin Analogue (Beraprost) Relief of Cold Intolerance After Digital Replantation and Revascularization
Authors: ISOGAI N. , MIYASATO Y. , ASAMURA S.
Published: May 2004

Cold intolerance frequently occurs after successful digital revascularization and replantation. A series of 11 patients with cold intolerance 6 to 24 months after digital revascularization/replantation were treated daily for 2 weeks with beraprost, a stable prostacyclin analogue. That pain was reduced in 9 of 11 cases after treatment and digital thermography showed significantly increased surface temperature after the 2-week course of beraprost. These findings support the use of beraprost to relieve symptoms of cold intolerance under these clinical conditions.
Repair of rabbit segmental defects with the thrombin peptide, TP508
Authors: Sheller Michael R. , Crowther Roger S. , Kinney John H. , Yang Jinping , Di Jorio Sherry , Breunig Tom , Carney Darrell H. , Ryaby James T.
Published: May 2004

The synthetic peptide, TP508 (Chrysalin®), was delivered to rabbit segmental bone defects in biodegradable controlled‐release PLGA microspheres to determine its potential efficacy for enhancing healing of non‐critically and critically sized segmental defects. Non‐critically sized radial defects were created in the forelimbs of New Zealand White rabbits, which were randomized into three treatment groups receiving 10, 50 and 100 μg doses of TP508 in the right radius and control microspheres (without TP508) in the left radius. Torsional testing of the radii at six weeks showed a significant increase in ultimate torque, failure torque, ultimate energy, failure energy, and stiffness when treated with TP508 compared to controls (p < 0.01 for all measures). Thus, TP508 appeared to enhance or accelerate bone growth in these defects.

In a second set of experiments, critically sized ulnar defects were created in the forelimbs of New Zealand White rabbits, which were randomized into two groups with each rabbit receiving microspheres with 100 or 200 μg of TP508 into the right ulnar defect and control microspheres (without TP508) alone into the left ulnar defect. Bone healing was evaluated with plain radiographs, synchrotron‐based microtomography, and mechanical testing. Radiographs of the rabbit limbs scored by three blinded, independent reviewers demonstrated a significantly higher degree of healing when treated with TP508 than their untreated control limbs (p < 0.05). Three‐dimensional synchrotron tomography of a limited number of samples showed that the new bone in TP508‐treated samples had a less porous surface appearance and open marrow spaces, suggesting progression of bone remodeling. Torsional testing of the ulnae at nine weeks showed a significant increase in maximum torque and failure energy when treated with TP508 compared to controls (p < 0.01 for both measures). These results suggest that TP508 in a controlled release delivery vehicle has the potential to enhance healing of segmental defects in both critically and non‐critically sized defects. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Production of consistent crush lesions in murine quadriceps muscle—A biomechanical, histomorphological and immunohistochemical study
Authors: Bunn Jonathan R. , Canning John , Burke George , Mushipe Moses , Marsh David R. , Li Gang
Published: May 2004

Poor healing of high‐energy fractures is often associated with severe muscle damage. This may be partly due to the production, by the injured muscle, of inflammatory cytokines that somehow misdirect bone healing. In order to investigate this question, an animal model was established which embodies a controlled degree of muscle injury with a dose response to the energy absorbed, that can be characterised histologically. Using a custom crush jig, 60 CFLP mice had either 100 or 200 g masses dropped from a fixed height onto the quadriceps muscle, with mechanical measurement of the impact. Energy of impact was reliably and significantly different between the small and large impact conditions, though there was more variability when the large mass was used. Animals were sacrificed at day 2, 4, 8, 16, and 24 post‐injury. Muscle histomorphometry at all time points and immunohistochemistry for IL‐1β, IL‐6, and TNF‐α up to day 8 were used as measures of muscle damage, inflammation and repair. Histological sections were analysed into areas of normal muscle fibres, damaged/regenerating muscle fibres and fibrous/inflammatory infiltrate. Early histological response was similar between the two groups; the large crush group displayed significantly greater areas of inflammatory infiltrate and damaged muscle at the later time points after day 8. In the large crush group, IL‐1β and IL‐6 expression were significantly higher at day 2 and TNF‐α was higher at day 8 when compared to the small crush group.

The experiment demonstrated that more severe injury to muscle was reliably followed by increased inflammatory cytokine production and a greater degree of inflammation and fibrosis. Increased production of inflammatory cytokines such as TNF‐α and IL‐1β in the damaged muscles may activate macrophages and recruit fibroblasts, promote scar formation and lead to delayed union or non‐union of the adjacent fracture(s). © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.
Neuronal regeneration after application of radiofrequency energy to collagenous tissue is affected by limb immobilization: An in vivo animal study
Authors: Pötzl W. , Kümpers P. , Szuwart T. , Filler T. , Marquardt B. , Steinbeck J.
Published: May 2004

Despite widespread use of radiofrequency (RF)‐shrinkage, there have been no studies on the influence of RF‐energy on neural elements of collagenous tissue. The purpose of this study was to examine the effect of RF‐shrinkage on neural structures of capsuloligamentous tissue and the recovery of neural elements under different postoperative treatment protocols.

One patellar tendon of 46 New‐Zealand‐White rabbits was shrunk. Six rabbits were sacrificed immediately postoperative. Twenty rabbits were not immobilized, 10 were immobilized for 3 and 10 were immobilized for 6 weeks. A monoclonal antibody, specific against a neurofilament protein, was used to detect nerves and neural structures.

Staining pattern of nerve fibres was significantly altered immediately postoperative. After 3 weeks the number of nerve fibres and bundles decreased significantly in immobilized and non‐immobilized limbs. The loss of nerve fibres was significantly less in immobilized limbs. At 6 weeks the number of neural elements in immobilized limbs increased to the level of untreated control tissue. In non‐immobilized limbs we found no recovery of neural elements 9 weeks postoperatively. At this time the number of nerve fibres and bundles was still significantly less compared to the untreated control limbs.

RF‐shrinkage causes significant alteration of neural elements. Under immobilization nerve fibres and bundles reach the level of normal untreated tissue. Careful rehabilitation is important after RF‐shrinkage. Not only for biomechanical reasons, but also to allow the neural elements to recover, thermally modified tissue should be protected from normal physiologic loads. © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.
A histomorphological study of tendon reconstruction to a hydroxyapatite‐coated implant: Regeneration of a neo‐enthesis in vivo
Authors: Pendegrass C. J. , Oddy M. J. , Cannon S. R. , Briggs T. , Goodship A. E. , Blunn G. W.
Published: May 2004

The attachment of tendons and ligaments to massive endoprostheses remains a clinical challenge due to the difficulty in achieving a soft tissue implant interface with a mechanical strength sufficient to transmit the forces necessary for locomotion. We have used an in vivo animal model to study patellar tendon attachment to an implant surface. The interface generated when the patellar tendon was attached to a hydroxyapatite (HA) coated implant was examined using light microscopy and a quantitative histomorphological analysis was performed. In the Autograft Group, the interface was augmented with autogenous cancellous bone and marrow graft, and at six weeks an indirect‐like insertion was observed. At twelve weeks, the interface was observed to be a layered neo‐enthesis, whose morphology was similar to a normal direct tendon insertion. In the HA Group, the tendon–implant interface was not augmented, and the implant was enveloped by a dense collagenous fibrous tissue.

This study shows that a tendon–implant neo–enthesis can develop in situ by employing a suitable implant surface in association with biological augmentation. © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.