bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneity of the neuropeptide Y (NPY) contractile and relaxing receptors in horse penile small arteries
Authors: Prieto Dolores , Rivera de los Arcos Luis , Martínez Pilar , Benedito Sara , García‐Sacristán Albino , Hernández Medardo 
Published: November 2004

The distribution of neuropeptide Y (NPY)‐immunorective nerves and the receptors involved in the effects of NPY upon electrical field stimulation (EFS)‐ and noradrenaline (NA)‐elicited contractions were investigated in horse penile small arteries.
NPY‐immunoreactive nerves were widely distributed in the erectile tissues with a particularly high density around penile intracavernous small arteries.
In small arteries isolated from the proximal part of the corpora cavernosa, NPY (30 nM) produced a variable modest enhancement of the contractions elicited by both EFS and NA. At the same concentration, the NPY Y1 receptor agonist, [Leu31, Pro34]NPY, markedly potentiated responses to EFS and NA, whereas the NPY Y2 receptor agonist, NPY(13–36), enhanced exogenous NA‐induced contractions.
In arteries precontracted with NA, NPY, peptide YY (PYY), [Leu31, Pro34]NPY and the NPY Y2 receptor agonists, N‐acetyl[Leu28,31]NPY (24–36) and NPY(13–36), elicited concentration‐dependent contractile responses. Human pancreatic polypeptide (hPP) evoked a biphasic response consisting of a relaxation followed by contraction. NPY(3–36), the compound 1229U91 (Ile‐Glu‐Pro‐Dapa‐Tyr‐Arg‐Leu‐Arg‐Tyr‐NH2, cyclic(2,4′)diamide) and eventually NPY(13–36) relaxed penile small arteries.
The selective NPY Y1 receptor antagonist BIBP3226 ((R)‐N2‐(diphenacetyl)‐N‐[(4‐hydroxyphenyl)methyl]D‐arginineamide) (0.3 μM) shifted to the right the concentration–response curves to both NPY and [Leu31, Pro34]NPY and inhibited the contractions induced by the highest concentrations of hPP but not the relaxations observed at lower doses.
In the presence of the selective NPY Y2 receptor antagonist BIIE0246 ((S)‐N2‐[[1‐[2‐[4‐[(R,S)‐5,11‐dihydro‐6(6h)‐oxodibenz[b,e]azepin‐11‐y1]‐1‐piperazinyl]‐2‐oxoethyl]cyclo‐pentyl‐N‐[2‐[1,2‐dihydro–3,5 (4H)‐dioxo‐1,2‐diphenyl‐3H‐1,2, 4‐triazol‐4‐yl]ethyl]‐argininamide) (0.3 μM), the Y2 receptor agonists NPY(13–36) and N‐acetyl[Leu28,31]NPY (24–36) evoked potent slow relaxations in NA‐precontracted arteries, under conditions of nitric oxide (NO) synthase blockade.
Mechanical removal of the endothelium markedly enhanced contractions of NPY on NA‐precontracted arteries, whereas blockade of the neuronal voltage‐dependent Ca2+ channels did not alter NPY responses.
These results demonstrate that NPY can elicit dual contractile/relaxing responses in penile small arteries through a heterogeneous population of postjunctional NPY receptors. Potentiation of the contractions evoked by NA involve both NPY Y1 and NPY Y2 receptors. An NO‐independent relaxation probably mediated by an atypical endothelial NPY receptor is also shown and unmasked in the presence of selective antagonists of the NPY contractile receptors.

British Journal of Pharmacology (2004) 143, 976–986. doi:10.1038/sj.bjp.0706005
Tolerance develops in spinal cord, but not in brain with chronic [Dmt1]DALDA treatment
Authors: Ben Yong , Smith Andrew P , Schiller Peter W , Lee Nancy M 
Published: November 2004

Previously, we reported that H‐2′,6′‐dimethyltyrosine [Dmt1]‐D‐Arg‐Phe‐Lys‐NH2 (DALDA), an analogue of the naturally occurring opioid peptide dermorphin, is a highly potent and selective mu receptor agonist with low cross‐tolerance to morphine. In the present study, we investigated the effect of treating mice chronically with [Dmt1]DALDA. The AD50 of [Dmt1]DALDA (s.c.) increased eight‐fold in animals given this drug chronically; in contrast, the AD50 increased two‐fold in mice chronically treated with morphine. The AD50 of morphine (s.c.) in these [Dmt1]DALDA‐treated animals was increased more than 120 times, while that of the more selective μ agonist [D‐Ala2‐MePhe4‐Gly‐ol5]enkephalin (DAMGO) given intrathecally was increased more than 240 times. However, the AD50 of DAMGO given intracerebroventricularly was essentially the same in animals treated chronically with [Dmt1]DALDA as in naïve animals. The dose of naloxone required to precipitate withdrawal in [Dmt1]DALDA‐treated animals was 20 times lower than that in morphine‐tolerant animals.
Using real‐time quantitative PCR, we found that expression of the μ opioid receptor, δ opioid receptor, preproenkephalin and preprodynorphin genes was upregulated in the brain by [Dmt1]DALDA treatment. No significant changes in expression of opioid receptor or opioid peptide genes were detected in the spinal cord of [Dmt1]DALDA‐treated mice, nor in the brain or spinal cord of morphine‐treated mice. We conclude that a high degree of tolerance to [Dmt1]DALDA develops in the spinal cord but not brain, and cannot be accounted for by changes in expression of opioid receptors or opioid peptides in these tissues.

British Journal of Pharmacology (2004) 143, 987–993. doi:10.1038/sj.bjp.0706007
FINE STRUCTURAL STUDIES ON THE INTERPHASE AND DIVIDING APICAL CELLS OF SPHACELARIA TRIBULOIDES (PHAEOPHYTA)1
Authors: Katsaros Christos , Galatis Basil , Mitrakos Konstantinos 
Published: November 2004

ABSTRACTThe apical cells of Sphacelaria tribuloides Menegh. are larger than other thallus cells, contain more organelles and appear polarized. Their tip portion, where they grow, contains a well developed Golgi apparatus, abundant endoplasmic reticulum (ER) membranes, mitochondria, chloroplasts and a large number of small vacuoles. It seems likely that a continuous flow of membranous material from the ER membranes to the dictyosomes and from the latter to the plasmalemma of the extending tip portion takes place. In contrast, the basal pole possesses fewer organelles and is occupied mainly by large‐sized, sometimes central vacuoles. The apical cells undergo two distinct types of highly asymmetrical differential divisions giving rise to cells of the thallus and hair initials. During the early stages of mitosis the nuclear envelope remains intact, except for fenestrated poles. Microtubules pass through the fenestrae into the nucleoplasm. During meta‐phase, a typical chromosome plate is organized. The sites of attachment of spindle microtubules to the chromosomes are structurally different from the rest of the chromosomes. At late anaphase, the nuclear envelope breaks down completely. During telophase, a new membrane encloses the chromosomes which are decondensed and the nucleoli are reorganized. Cytokinesis proceeds long after mitosis at a stage in which the nuclei have increased in size and have moved farther apart. A membranous furrow develops centripetally, without the participation of microtubules. However, microtubules traverse the thin cytoplasmic strands which, in both interphase and cytokinetic cells, meander among the vacuoles of the basal pole of the cell and the internuclear space. Dictyosomes appear to be involved in the subsequent wall deposition.
The steppe pika Ochotona pusilla in Britain, and a new northerly record
Authors: FISHER C. T. , YALDEN D. W. 
Published: November 2004

ABSTRACTThe known localities for steppe pika Ochotona pusilla, which occurred in Britain during Late Pleistocene times, are reviewed. A previously misidentified lower jaw, from Helsfell Cave in the Lake District, Cumbria extends the known range of this species in Britain 100 km further north.
The Extra‐Parliamentary Tory Party: McKenzie Revisited
Authors: KELLY RICHARD 
Published: November 2004

This chapter almost coincides with the fiftieth anniversary of Robert McKenzie's British Political Parties, a study which contested that power in the Tory party was centralised in its Parliamentary leadership, with its constituency members having only a marginal influence. The chapter revisits McKenzie's analysis in the light of developments since 2001, particularly the victory of Iain Duncan Smith in that year's 'democratised' Conservative leadership contest.The chapter argues that Duncan Smith's victory strengthened McKenzie's claim that democratised parties are seldom popular, and describes how IDS, ironically, spawned reforms that diminished his extra‐Parliamentary supporters. But the chapter is also an updated reminder that McKenzie underrated grass root power in certain areas ‐ notably candidate selection ‐ and suggests a lesson from the Tories' short‐lived revival under Michael Howard, namely that long‐term party recovery requires an energised party membership as well as a competent party leader.
Corporate Investment and Asset Price Dynamics: Implications for the Cross‐section of Returns
Authors: CARLSON MURRAY , FISHER ADLAI , GIAMMARINO RON 
Published: November 2004

ABSTRACTWe show that corporate investment decisions can explain the conditional dynamics in expected asset returns. Our approach is similar in spirit to Berk, Green, and Naik (1999), but we introduce to the investment problem operating leverage, reversible real options, fixed adjustment costs, and finite growth opportunities. Asset betas vary over time with historical investment decisions and the current product market demand. Book‐to‐market effects emerge and relate to operating leverage, while size captures the residual importance of growth options relative to assets in place. We estimate and test the model using simulation methods and reproduce portfolio excess returns comparable to the data.
Near‐sighted Justice
Authors: BERNHARDT DAN , NOSAL ED 
Published: November 2004

ABSTRACTChapter 11 structures complex negotiations between creditors and debtors that are overseen by a bankruptcy court. We identify conditions where the court should sometimes err in determining which firms should be liquidated. Such errors affect actions by both good and bad entrepreneurs. We first characterize the optimal error rate without renegotiation. When creditors and debtors can renegotiate to circumvent an error‐riven court, for one class of actions a blind court that ignores all information is optimal. For another class, the court should place the burden of proof on the entrepreneur. The robust feature is that the court should sometimes err.
Systemic Risk and International Portfolio Choice
Authors: DAS SANJIV RANJAN , UPPAL RAMAN 
Published: November 2004

ABSTRACTReturns on international equities are characterized by jumps; moreover, these jumps tend to occur at the same time across countries leading to systemic risk. We capture these stylized facts using a multivariate system of jump‐diffusion processes where the arrival of jumps is simultaneous across assets. We then determine an investor's optimal portfolio for this model of returns. Systemic risk has two effects: One, it reduces the gains from diversification and two, it penalizes investors for holding levered positions. We find that the loss resulting from diminished diversification is small, while that from holding very highly levered positions is large.
Yersinia enterocolitica
Adhesin A Induces Production of Interleukin-8 in Epithelial Cells
Authors: Schmid Yvonne , Grassl Guntram A. , Bühler Oliver T. , Skurnik Mikael , Autenrieth Ingo B. , Bohn Erwin 
Published: November 2004

ABSTRACT

The major invasive factor of
Yersinia enterocolitica
, the invasin (Inv) protein, induces proinflammatory host cell responses, including interleukin-8 (IL-8) secretion from human epithelial cells, by engagement of β1 integrins. The Inv-triggered β1 integrin signaling involves the small GTPase Rac; the activation of MAP kinases, such as p38, MEK1, and JNK; and the activation of the transcription factor NF-κB. In the present study, we demonstrate that
Y. enterocolitica
YadA, which is a major adhesin of
Y. enterocolitica
with pleiotropic virulence effects, induces IL-8 secretion in epithelial cells. The abilites of YadA and Inv to promote adhesion to and invasion of HeLa cells and to induce IL-8 production by the cells were investigated by expression of YadA and Inv in
Escherichia coli
. While YadA mediates efficacious adhesion to HeLa cells, it mediates marginal invasion compared with Inv. Both YadA and Inv trigger comparable levels of IL-8 production. Conformational changes of the YadA head domain by mutation of NSVAIG-S motifs, which abolish collagen binding, also abolish adhesion of
Yersinia
to HeLa cells and YadA-mediated IL-8 secretion. Furthermore, experiments in which blocking antibodies against β1 integrins were used demonstrate that β1 integrins are crucial for YadA-mediated IL-8 secretion. Inhibitor studies demonstrate the involvement of small GTPases and MAP kinases, such as p38, MEK1, and JNK, indicating that β1 integrin-dependent signaling mediated by Inv or YadA involves similar signaling pathways. These data present YadA, in addition to Inv, YopB, and
Yersinia
lipopolysaccharide, as a further inducer of proinflammatory molecules by which
Y. enterocolitica
might promote inflammatory tissue reactions.
The Major Histocompatibility Complex Haplotype Affects T-Cell Recognition of Mycobacterial Antigens but Not Resistance to
Mycobacterium tuberculosis
in C3H Mice
Authors: Kamath Arati B. , Alt Jennifer , Debbabi Hajer , Taylor Chad , Behar Samuel M. 
Published: November 2004

ABSTRACT

Both innate and adaptive immunity play an important role in host resistance to
Mycobacterium tuberculosis
infection. Although several studies have suggested that the major histocompatibility complex (MHC) haplotype affects susceptibility to infection, it remains unclear whether the modulation of T-cell immunity by the MHC locus determines the host's susceptibility to tuberculosis. To determine whether allelic differences in the MHC locus affect the T-cell immune response after
M. tuberculosis
infection, we infected inbred and H-2 congenic mouse strains by the respiratory route. The H-2 locus has a profound effect on the antigen-specific CD4
+
-T-cell response after
M. tuberculosis
infection. CD4
+
T cells from infected mice of the H-2
b
haplotype produced more gamma interferon (IFN-γ) after in vitro stimulation with mycobacterial antigens than mice of the H-2
k
haplotype. A higher level of IFN-γ was also detected in bronchoalveolar lavage fluid from infected mice of the H-2
b
haplotype. Furthermore, C3.SW-H2
b
/SnJ mice generate and recruit activated T cells to the lung after infection. Despite a robust immune response, C3.SW-H2
b
/SnJ mice succumbed to infection early and were similarly susceptible to infection as other C3H (H-2
k
) substrains. These results suggest that although the MHC haplotype has a profound impact on the T-cell recognition of
M. tuberculosis
antigens, the susceptibility of C3H mice to infection is MHC independent.
Protective Immunity against
Eimeria acervulina
following In Ovo Immunization with a Recombinant Subunit Vaccine and Cytokine Genes
Authors: Ding Xicheng , Lillehoj Hyun S. , Quiroz Marco A. , Bevensee Erich , Lillehoj Erik P. 
Published: November 2004

ABSTRACT

A purified recombinant protein from
Eimeria acervulina
(3-1E) was used to vaccinate chickens in ovo against coccidiosis both alone and in combination with expression plasmids encoding the interleukin 1 (IL-1), IL-2, IL-6, IL-8, IL-15, IL-16, IL-17, IL-18, or gamma interferon (IFN-γ) gene. When used alone, vaccination with 100 or 500 μg of 3-1E resulted in significantly decreased oocyst shedding compared with that in nonvaccinated chickens. Simultaneous vaccination of the 3-1E protein with the IL-1, -15, -16, or -17 gene induced higher serum antibody responses than 3-1E alone. To evaluate protective intestinal immunity, vaccinated birds were challenged with live
E. acervulina
oocysts 14 days posthatch, and fecal-oocyst shedding and body weight gain were determined as parameters of coccidiosis. Chickens vaccinated with 3-1E protein showed significantly lower oocyst shedding and normal body weight gain than nonvaccinated and infected controls. Simultaneous immunization with 3-1E and the IL-2, -15, -17, or -18 or IFN-γ gene further reduced oocyst shedding compared with that achieved with 3-1E alone. These results provide the first evidence that in ovo vaccination with the recombinant 3-1E
Eimeria
protein induces protective intestinal immunity against coccidiosis, and this effect was enhanced by coadministration of genes encoding immunity-related cytokines.
Immunostimulating Properties of Intragastrically AdministeredAcetobacter-Derived Soluble Branched (1,4)-β-d-Glucans Decrease Murine Susceptibility toListeria monocytogenes
Authors: Li Wei , Yajima Toshiki , Saito Kimika , Nishimura Hitoshi , Fushimi Takashi , Ohshima Yoshifumi , Tsukamoto Yoshinori , Yoshikai Yasunobu 
Published: November 2004

ABSTRACTWe previously found that AC-1, an extracellular polysaccharide, produced byAcetobacter xylinumand composed of (1,4)-β-d-glucan with branches of glucosyl residues, showed a strong activity to induce production of interleukin-12 (IL-12) p40 and tumor necrosis factor alpha by macrophages in vitro via Toll-like receptor 4 (TLR-4) signaling. In the present study, we examined the effect of oral administration of AC-1 on protective immunity againstListeria monocytogenes. Mice were given AC-1 or phosphate-buffered saline (PBS) intragastrically 2 days before, on the day of, and 2 days after an intraperitoneal inoculation ofL. monocytogenes. The survival rate of AC-1-treated mice was significantly improved and bacterial growth in AC-1-treated mice was severely retarded compared to those of PBS-treated mice after infection withL. monocytogenes. IL-12 p40 levels in serum and magnitudes of CD4+Th1 and CD8+Tc1 responses againstListeriaantigen were significantly higher in AC-1-treated mice than in PBS-treated mice. The effect of AC-1 on antilisterial activity was diminished in C3H/HeJ mice carrying mutated TLR-4. Thus, AC-1, a potent IL-12 inducer through TLR-4, enhanced protective immunity againstL. monocytogenesvia augmentation of Th1 responses. These results suggest that infectious processes driven by intracellular microorganisms could be prevented to develop by the (1,4)-β-d-glucan.
Oral Vaccination of BALB/c Mice withSalmonella entericaSerovar Typhimurium ExpressingPseudomonas aeruginosaO Antigen Promotes Increased Survival in an Acute Fatal Pneumonia Model
Authors: DiGiandomenico Antonio , Rao Jayasimha , Goldberg Joanna B. 
Published: November 2004

ABSTRACTPseudomonas aeruginosais a leading cause of nosocomial pneumonia. We compared the efficacies of oral and intraperitoneal (i.p.) vaccinations of BALB/c mice with attenuatedSalmonella entericaserovar Typhimurium SL3261 expressingP. aeruginosaserogroup O11 O antigen to protect againstP. aeruginosainfection in an acute fatal pneumonia model. Oral and i.p. vaccines elicited O11-specific serum immunoglobulin G (IgG) antibodies, but IgA was observed only after oral immunization. Challenge of orally vaccinated mice with an O11 strain (9882-80) at 6 and 12 times the 50% lethal dose showed increased survival in mice that received the vaccine compared to phosphate-buffered saline (PBS)- and vector-treated controls; no difference in survival was seen with a heterologous strain, 6294 (serogroup O6). In addition, significant protection against 9882-80 was not observed in i.p. vaccinated animals. Bronchoalveolar lavage fluid taken from immunized mice harbored O11-specific IgA and IgG in orally immunized mice but only modest levels of IgG in i.p. vaccinated mice. To correlate protection, opsonophagocytosis assays were performed with pooled sera from orally immunized animals. Efficient killing of five O11 clinical isolates was observed, while no killing was noted with 6294, indicating that the recombinant SL3261 oral vaccine induces an O11-specific reaction. We next determined the ability of orally vaccinated animals to clear bacteria from their lungs. FollowingP. aeruginosachallenge, the numbers of viable bacteria were significantly fewer in orally vaccinated animals than in PBS- and vector-treated controls. Our results suggest that oral immunization with recombinant SL3261 is efficacious in protection against pneumonia caused byP. aeruginosa.
First-Time Isolation and Characterization of a Bacteriophage Encoding the Shiga Toxin 2c Variant, Which Is Globally Spread in Strains of
Escherichia coli
O157
Authors: Strauch Eckhard , Schaudinn Christoph , Beutin Lothar 
Published: November 2004

ABSTRACT

A bacteriophage encoding the Shiga toxin 2c variant (Stx2c) was isolated from the human
Escherichia coli
O157 strain CB2851 and shown to form lysogens on the
E. coli
K-12 laboratory strains C600 and MG1655. Production of Stx2c was found in the wild-type
E. coli
O157 strain and the K-12 lysogens and was inducible by growing bacteria in the presence of ciprofloxacin. Phage 2851 is the first reported viable bacteriophage which carries an
stx
2c
gene. Electron micrographs of phage 2851 showed particles with elongated hexagonal heads and long flexible tails resembling phage lambda. Sequence analysis of an 8.4-kb region flanking the
stx
2c
gene and other genetic elements revealed a mosaic gene structure, as found in other Stx phages. Phage 2851 showed lysis of
E
.
coli
K-12 strains lysogenic for Stx phages encoding Stx1 (H19), Stx2 (933W), Stx (7888), and Stx1c (6220) but showed superinfection immunity with phage lambda, presumably originating from the similarity of the
c
I repressor proteins of both phages. Apparently, phage 2851 integrates at a different chromosomal locus than Stx2 phage 933W and Stx1 phage H19 in
E. coli
, explaining why Stx2c is often found in combination with Stx1 or Stx2 in
E. coli
O157 strains. Diagnostic PCR was performed to determine gene sequences specific for phage 2851 in wild-type
E. coli
O157 strains producing Stx2c. The phage 2851
q
and
o
genes were frequently detected in Stx2c-producing
E
.
coli
O157 strains, indicating that phages related to 2851 are associated with Stx2c production in strains of
E. coli
O157 that were isolated in different locations and time periods.
Streptococcal Pyrogenic Exotoxin B-Induced Apoptosis in A549 Cells Is Mediated by a Receptor- and Mitochondrion-Dependent Pathway
Authors: Tsai Wan-Hua , Chang Chia-Wen , Chuang Woei-Jer , Lin Yee-Shin , Wu Jiunn-Jong , Liu Ching-Chuan , Chang Wen-Tsan , Lin Ming T. 
Published: November 2004

ABSTRACT

It has been shown that streptococcal pyrogenic exotoxin B (SPE B) can induce cells to undergo apoptosis. The present study is to dissect the role of SPE B protease and SPE B protein in the apoptotic process of A549 cells and to elucidate the SPE B-induced apoptotic pathway. Recombinant SPE B (rSPE B) and C192S, a mutant of SPE B without protease activity, were expressed in
Escherichia coli
and purified by using an affinity column. The apoptosis of A549 cells was assayed by propidium iodide staining, followed by flow cytometry analysis. Our results showed that SPE B induced apoptosis in a dose-dependent manner, whereas C192S did not. When cells were pretreated with rSPE B (2 μg/ml) for as briefly as 5 min and then incubated with C192S of 28 kDa, an apoptosis that is proportional to the period of pretreatment was observed but not with C192S of 42 kDa. These results suggest that the extracellular protease activity of rSPE B is required for the initiation of apoptosis and that the size of SPE B is important for an effective induction of apoptosis. The time course analysis revealed that molecules activated in apoptosis were in the following order: caspase-8 (1.5 h), t-Bid (2.5 h), Bax (3 h), cytochrome
c
release (6 h), caspase-9 (7 h), and caspase-3 (8 h). The overexpression of Bcl-2 inhibited depolarization of mitochondrial membrane, cytochrome
c
release, and apoptosis. The results of the present study suggest that SPE B-induced apoptosis is mediated through a receptor-like mechanism and a mitochondrion-dependent pathway.