bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of hydrated and/or hydroxylated minerals on the surface of asteroid 4 Vesta
Authors: Hasegawa Sunao , Murakawa Koji , Ishiguro Masateru , Nonaka Hidenori , Takato Naruhisa , Davis Chris J. , Ueno Munetaka , Hiroi Takahiro
Published: November 2003

Asteroid 4 Vesta is thought to be a differentiated object with intact internal structure due to its achondritic surface. In this paper, we report K‐L band spectroscopic observations of Vesta. We have detected the presence of a 3‐μm absorption feature at about the 1% level on the surface of Vesta at longitudes between 155° and 195°. This result indicates that OH and/or H2O‐bearing minerals are present in this region of Vesta; the sources are plausibly fragments of carbonaceous chondrite impactors or solar wind implantation. The detection of 3‐μm absorption features from Vesta, regarded as the smallest terrestrial planet, may provide clues to the origin of volatile materials on terrestrial planets.
Ion transport and Lévy random walk across the magnetopause in the presence of magnetic turbulence
Authors: Greco A. , Taktakishvili A. L. , Zimbardo G. , Veltri P. , Cimino G. , Zelenyi L. M. , Lopez R. E.
Published: November 2003

A numerical study of magnetosheath ion motion in the magnetopause current sheet in the presence of magnetic fluctuations is reported. Test particles are injected at the magnetosheath side only. The magnetic field turbulence is modeled as a power law spectrum in phase space, which reaches maximum intensity in the center of the magnetopause current sheet and decreases toward the magnetosheath and magnetosphere boundaries, creating magnetic islands. The number of particles entering the magnetosphere, reflected from the magnetopause, and flowing away from the flanks is computed, as a function of the fluctuation level of the turbulence and of the magnetic field shear parameter. All those quantities appear to be strongly dependent on the fluctuation level, with the number of particles entering the magnetopause increasing with the fluctuation level. The density profile for a localized source in the magnetosheath is not Gaussian but rather has a long tail extending into the magnetopause. The statistical analysis of the ion motion along the direction normal to the magnetopause reveals that the ions perform a Lévy random walk, so that the penetrating particles could reach the magnetospheric side of the simulation box with few long jumps in between the magnetic islands. This shows that plasma transport across the magnetopause in presence of magnetic turbulence is non‐Gaussian and needs to be described in terms of enhanced, superdiffusive transport.
A downscaling framework for L band radiobrightness temperature imagery
Authors: Parada Laura M. , Liang Xu
Published: November 2003

In this paper we introduce a general downscaling framework and apply it to L band microwave radiobrightness temperature fields retrieved from electronically scanned thinned array radiometer (ESTAR). The gist of the downscaling scheme presented in this paper is the statistical characterization of scale‐invariant properties of the wavelet coefficients or fluctuations from long memory 1/f processes. We test the proposed downscaling framework with the radiobrightness temperature images collected during the Southern Great Plains hydrology experiment of 1997. We produce realizations of radiobrightness temperature at 800‐m resolution given a mean‐area value at approximately 30‐km resolution (the near‐future expected operational scale). The results obtained evince that the proposed downscaling methodology is capable of accurately preserving the variability and overall structure of spatial dependence of the observed radiobrightness temperature fields.
Protection, Dissociation, and Internal Roles: Modeling and Treating the Effects of Child Abuse
Authors: Thomas Peter M.
Published: November 2003

This article presents a theory of the long-term effects of child abuse that emphasizes the development of internal working models of protection. The theory proposes that abused children do not receive adequate caregiver protection and do not form internal representations of an effective protector. As a result, they have ongoing difficulty defending themselves against interpersonal aggression and internal self-criticism. The model integrates current research and theory in attachment behavior, developmental psychopathology, trauma, dissociation, and experiential psychotherapy. It accounts for many of the clinical symptoms presented by adult survivors of child abuse and suggests specific strategies for treatment. The author provides 3 examples of psychotherapy interventions derived from the model, distinguishes protection and “rescuing,” and suggests directions for future research.
Extracellular ATP and adenosine induce cell apoptosis of human hepatoma Li‐7A cells via the A3 adenosine receptor
Authors: Wen Long T , Knowles Aileen F
Published: November 2003

Extracellular ATP is a potent signaling molecule that modulates a myriad of cellular functions through the activation of P2 purinergic receptors and is cytotoxic to a variety of cells at higher concentrations. The mechanism of ATP‐elicited cytotoxicity is not fully understood. In this study, we investigated the effect of extracellular ATP on the human hepatoma Li‐7A cells.

We observed a time‐ and dose‐dependent growth inhibition of Li‐7A cells by ATP, which is accompanied by an increase in the active form of caspase‐3 as well as increased cleavage of its substrate, poly (ADP‐ribose) polymerase. The cytotoxic effect of extracellular ATP was not mediated by the P2X7 receptor, since (1) the effect was not abolished by the P2X7 receptor antagonists oxidized ATP and KN‐62, and (2) extracellular ADP, AMP, and adenosine were also cytotoxic.

We found that ATP and ADP were degraded to adenosine by Li‐7A cells and that treatment of Li‐7A cells by adenosine resulted in growth inhibition and caspase‐3 activation, indicating that adenosine is the apoptotic agent. Using adenosine receptor agonists and antagonists, as well as inhibitors of adenosine transport and deamination, we showed that the cytotoxic effect of adenosine is specifically mediated by the A3 receptor even though transcripts of A1, A2A, A2B, and a splice variant of the P2X7 receptors were detected in Li‐7A cells by RT–PCR.

Cytotoxicity caused by exogenous ATP and adenosine was completely abolished by the caspase‐3 inhibitor Z‐DEVD‐FMK, demonstrating the central role of caspase‐3 in apoptosis of Li‐7A cells.

British Journal of Pharmacology (2003) 140, 1009–1018. doi:10.1038/sj.bjp.0705523
Methyridine (2‐[2‐methoxyethyl]‐pyridine]) and levamisole activate different ACh receptor subtypes in nematode parasites: a new lead for levamisole‐resistance
Authors: Martin Richard J , Bai Guangxing , Clark Cheryl L , Robertson Alan P
Published: November 2003

The development of resistance to all chemotherapeutic agents increases and needs to be addressed. We are interested in resistance in parasitic nematodes to the anthelmintic levamisole. During studies on methyridine, we found that it gave us a new insight into pharmacological changes associated with levamisole resistance. Initially, electrophysiological investigation using a two‐micropipette current‐clamp recording technique revealed that methyridine acts as a cholinergic agonist on nematode muscle receptors (Ascaris suum). Methyridine (>30 μM) produced reversible concentration‐dependent depolarizations and increases in input conductance. Mecamylamine (30 μM) and paraherquamide (0.3 μM) produced reversible antagonism of the depolarization and conductance responses to methyridine. These observations suggest that methyridine, like acetylcholine and levamisole, gates ion channels on the muscle of parasitic nematodes.

The antagonistic effects of dihydro‐β‐erythroidine and paraherquamide on methyridine‐induced contractions of A. suum muscle flaps were then examined to determine if methyridine showed subtype selectivity for N‐subtype (nicotine‐sensitive) or L‐subtype (levamisole‐sensitive) acetylcholine receptors. Dihydro‐β‐erythroidine weakly antagonized the effects of methyridine (but had no effect on levamisole responses). The antagonism of methyridine (pA2, 5.9) and nicotine (pA2, 6.1) by paraherquamide was similar, but was less than the antagonism of levamisole (pA2, 7.0). The antagonist profiles suggested that methyridine has a selective action on the N‐subtype rather than on the L‐subtype.

A novel use for a larval inhibition migration assay was made using L3 larvae of Oesophagostomum dentatum. Inhibitory effects of nicotine, levamisole, pyrantel and methyridine on the migration of larvae of levamisole‐sensitive (SENS) and levamisole‐resistant (LEV‐R) isolates were tested at different concentrations. Levamisole and pyrantel (putative L‐subtype‐selective agonists) concentration–response plots were displaced to the right in LEV‐R isolates. Nicotine (an N‐subtype‐selective agonist) and methyridine produced little shift in concentration–response plots in the LEV‐R isolates. Resistance dose ratios were used to calculate the relative selectivity, ρL, for the L‐type receptor (levamisole ρL=1.0; pyrantel ρL=0.93; methyridine ρL=0.17; nicotine ρL=0.06). These observations reveal an N‐subtype‐selective action of methyridine and suggest that levamisole resistance may be associated with a loss of the L‐subtype, but not the N‐subtype receptors. The pharmacology of methyridine suggests an approach for the treatment of levamisole‐resistant parasites.

British Journal of Pharmacology (2003) 140, 1068–1076. doi:10.1038/sj.bjp.0705528
The CB1/VR1 agonist arvanil induces apoptosis through an FADD/caspase‐8‐dependent pathway
Authors: Sancho Rocío , De La Vega Laureano , Appendino Giovanni , Di Marzo Vincenzo , Macho Antonio , Muñoz Eduardo
Published: November 2003

Arvanil (N‐arachidonoylvanillamine), a nonpungent capsaicin–anandamide hybrid molecule, has been shown to exert biological activities through VR1/CB1‐dependent and ‐independent pathways. We have found that arvanil induces dose‐dependent apoptosis in the lymphoid Jurkat T‐cell line, but not in peripheral blood T lymphocytes. Apoptosis was assessed by DNA fragmentation through cell cycle and TUNEL analyses.

Arvanil‐induced apoptosis was initiated independently of any specific phase of the cell cycle, and it was inhibited by specific caspase‐8 and ‐3 inhibitors and by the activation of protein kinase C. In addition, kinetic analysis by Western blots and fluorimetry showed that arvanil rapidly activates caspase‐8, ‐7 and ‐3, and induces PARP cleavage.

The arvanil‐mediated apoptotic response was greatly inhibited in the Jurkat‐FADDDN cell line, which constitutively expresses a negative dominant form of the adapter molecule Fas‐associated death domain (FADD). This cell line does not undergo apoptosis in response to Fas (CD95) stimulation.

Using a cytofluorimetric approach, we have found that arvanil induced the production of reactive oxygen species (ROS) in both Jurkat‐FADD+ and Jurkat‐FADDDN cell lines. However, ROS accumulation only plays a residual role in arvanil‐induced apoptosis.

These results demonstrate that arvanil‐induced apoptosis is essentially mediated through a mechanism that is typical of type II cells, and implicates the death‐inducing signalling complex and the activation of caspase‐8. This arvanil‐apoptotic activity is TRPV1 and CB‐independent, and can be of importance for the development of potential anti‐inflammatory and antitumoral drugs.

British Journal of Pharmacology (2003) 140, 1035–1044. doi:10.1038/sj.bjp.0705532
Effects of endomorphin on substantia gelatinosa neurons in rat spinal cord slices
Authors: Wu Su‐Ying , Ohtubo Yoshitaka , Brailoiu G Cristina , Dun Nae J
Published: November 2003

Whole‐cell patch recordings were made from substantia gelatinosa (SG) neurons in transverse lumbar spinal cord slices of 15‐ to 30‐day‐old rats.

Endomorphin 1 (EM‐1) or EM‐2 (10 μM) hyperpolarized or induced an outward current in 26 of the 66 SG neurons. The I–V relationship showed that the peptide activates an inwardly rectifying K+ current.

EM‐1 or EM‐2 (0.3–10 μM) suppressed short‐latency excitatory postsynaptic currents (EPSCs) and long‐latency inhibitory postsynaptic currents (IPSCs) in nearly all SG neurons tested or short‐latency IPSCs in six of the 10 SG neurons. [Met5] enkephalin or [D‐Ala2, N‐Me‐Phe4, Gly5‐ol]‐enkephalin (DAMGO) (1–10 μM) depressed EPSCs and IPSCs. EM‐1 or EM‐2 depressed synaptic responses without causing a significant change in holding currents or inward currents induced by glutamate.

Glutamate also evoked a short‐latency outward current in five SG neurons or a biphasic current in two neurons; the outward current was blocked by tetrodotoxin (TTX, 0.3 μM) or bicuculline (10 μM). EM‐1 or DAMGO (1 or 5 μM) attenuated the glutamate‐evoked outward or biphasic currents in four of the seven SG neurons.

EM‐1 (1 μM) reduced the frequency, but not the amplitude of miniature EPSCs or miniature IPSCs.

Naloxone (1 μM) or the selective μ‐opioid receptor antagonist β‐funaltrexamine (β‐FNA, 25 μM) antagonized the action of EM; EM‐induced hyperpolarizations persisted in the presence of the κ‐opioid receptor antagonist (nor‐binaltorphimine dihydrochloride, 1 μM) and/or σ‐opioid receptor antagonist (naltrindole hydrochloride, 1 μM).

It may be concluded that EM acting on μ‐opioid receptors hyperpolarizes a population of SG neurons by activating an inwardly rectifying K+ current, and attenuates excitatory and inhibitory synaptic currents evoked in a population of SG neurons, probably by a presynaptic site of action.

British Journal of Pharmacology (2003) 140, 1088–1096. doi:10.1038/sj.bjp.0705534
Functional evidence that ATP or a related purine is an inhibitory NANC neurotransmitter in the mouse jejunum: study on the identity of P2X and P2Y purinoceptors involved
Authors: De Man Joris G , De Winter Benedicte Y , Seerden Tom C , De Schepper Heiko U , Herman Arnold G , Pelckmans Paul A
Published: November 2003

Conflicting views exist on whether ATP is a neurotransmitter in the enteric nervous system. We investigated the role of ATP in enteric transmission in circular muscle strips of the mouse jejunum.

On PGF2α‐precontracted muscle strips and in the presence of atropine and guanethidine, electrical field stimulation (EFS, 1–8 Hz) of nonadrenergic noncholinergic (NANC) nerves induced transient relaxations that were abolished by the nerve‐conductance blocker tetrodotoxin. The NO synthase blocker L‐nitroarginine (L‐NOARG) partially inhibited the NANC relaxations to EFS, but fast‐twitch relaxations to EFS were still observed in the presence of L‐NOARG.

In the presence of L‐NOARG, ATP, the P2X receptor agonist αβMeATP and the P2Y receptor agonist ADPβS relaxed jejunal muscle strips. Tetrodotoxin did not affect the relaxation to ATP and ADPβS, but inhibited that to αβMeATP.

The L‐NOARG‐resistant NANC relaxations to EFS were almost abolished by apamin, a blocker of small‐conductance Ca2+ activated K+ channels, and by suramin and PPADS, blockers of P2 purinoceptors. Relaxations to ATP were almost abolished by apamin and suramin but not affected by PPADS.

Desensitisation of αβMeATP‐sensitive P2X receptors, the P2X receptor blocker Evans blue and the P2X1,2,3 receptor blocker NF 279 inhibited the L‐NOARG‐resistant NANC relaxations to EFS and that to αβMeATP without affecting the relaxation to ADPβS. Brilliant blue G, a P2X2,5,7 receptor blocker, did not affect the relaxations to EFS.

Desensitisation of P2Y receptors and MRS 2179, a P2Y1 receptor blocker, virtually abolished the L‐NOARG‐resistant NANC relaxations to EFS and the relaxation to ADPβS without affecting the relaxation to αβMeATP.

Dipyridamole, an adenosine uptake inhibitor, or theophylline and 8‐phenyltheophylline, blockers of P1 and A1 purinoceptors, respectively, did not affect the purinergic NANC relaxations to EFS.

Our results suggest that ATP or a related purine acts as an inhibitory NANC neurotransmitter in the mouse jejunum, activating P2 but not P1 purinoceptors. Relaxations to the purinergic NANC neurotransmitter mainly involve P2Y receptors of the P2Y1 subtype that are located postjunctionally. Purinergic NANC neurotransmission also involves P2X receptors, most likely of the P2X1 and P2X3 subtype, located pre‐ and/or postjunctionally.

British Journal of Pharmacology (2003) 140, 1108–1116. doi:10.1038/sj.bjp.0705536
Activity of chlormethiazole at human recombinant GABAA and NMDA receptors
Authors: Usala Marcello , Thompson Sally Anne , Whiting Paul J , Wafford Keith A
Published: November 2003

Investigation into the modulatory effects of chlormethiazole at human recombinant γ‐aminobutyric acid A receptor (GABAA) and N‐methyl‐D‐aspartate (NMDA) receptors was undertaken to gain insight into its mechanism of action and determine if the drug exhibited any subtype‐selective activity.

Despite a structural similarity to the β‐subunit‐selective compound loreclezole, chlormethiazole did not show any difference in maximum efficacy and only a slight difference in EC50 in its potentiating action at α1β1γ2 and α1β2γ2 GABAA receptor subtypes with preference for α1β1γ2.

Similar to the previously reported subtype‐dependent activity of pentobarbital, chlormethiazole elicited a significantly greater degree of maximum potentiation on receptors lacking a γ2 subunit, and also those receptors containing an α4 or α6 subunit. This also demonstrates that chlormethiazole does not act via the benzodiazepine binding site.

Unlike pentobarbital and propofol, chlormethiazole elicited only a slight direct GABAA receptor activation at concentrations up to 1 mM. In addition, the drug did not potentiate anaesthetic‐mediated currents elicited by pentobarbital or propofol, suggesting that chlormethiazole may be acting via an anaesthetic binding site.

Chlormethiazole produced weak nonselective inhibition of human NMDA NR1a+NR2A and NR1a+NR2B receptors. IC50's were approximately 500 μM that likely exceed the therapeutic dose range for chlormethiazole, indicating that the primary mechanism of the compounds in vivo activity is via GABAA receptors.

British Journal of Pharmacology (2003) 140, 1045–1050. doi:10.1038/sj.bjp.0705540
Cultural Property, Restitution and Value
Authors: Thompson Janna
Published: November 2003

abstract  Demands for restitution of cultural artefacts and relics raise four main issues: 1) how claims to cultural property can be justified; 2) whether and under what conditions demands for restitution of cultural property are valid — especially when they are made long after the artefacts were taken away; 3) whether there are values, aesthetic, scholarly and educational, which can override restitution claims, even when these claims are legitimate; and 4) how these values bear on the question of whether artefacts should be returned to their place of origin. I argue that a proper conception of cultural property emphasises the role that artefacts play in the practices and traditions of a collectivity. On the basis of this conception, some restitution claims can be defended as legitimate. However, many demands for restitution are not justified (including the Greek claim to the Parthenon Marbles). Moreover, a case for restitution can be more or less strong, and other considerations sometimes prevail over rights of cultural property.
Presidential Renomination Challenges in the 20th Century
Authors: Steger Wayne P.
Published: November 2003

This article develops an expected utility model to derive the circumstances in which candidates might consider challenging an incumbent president seeking renomination. Candidates are hypothesized to challenge incumbents who (1) succeed to the presidency from the vice presidency, or (2) seek renomination amid an intra‐party split. Historical evidence is used to identify the circumstances in which renomination challenges occur and the consequences for the general election. The evidence supports both hypotheses, especially the hypothesis that vice presidents are likely to be challenged if they seek renomination. The magnitude of renomination challenges relates positively to the incumbent's chances of winning reelection.
Elections: Was the 2000 Presidential Election Fair? An Analysis of Comparative and Retrospective Survey Data
Authors: Wattenberg Martin P.
Published: November 2003

This research note reviews American National Election Studies data from 1996, 2000, and 2002 regarding the fairness of recent presidential elections. The findings from 1996 indicate that even in the face of a normal undisputed presidential election, Americans did not rate the fairness of their election particularly high compared to citizens of other established democracies. And in the shadow of the contested outcome of the 2000 American presidential race, complaints were rampant. In 2002, lingering bitterness about the election remained strong, and the patterns of opinion on this question had hardened along party lines.
The Law: Congressional Access to Presidential Documents: The House Resolution of Inquiry
Authors: Fisher Louis
Published: November 2003

The resolution of inquiry is a House procedure that seeks factual information from the executive branch, either from the president or department heads. The resolution is privileged and may be considered at any time after it is reported or discharged from committee. It applies only to requests for facts—not opinions—within the administration's control. Even when a resolution of inquiry is reported adversely from a committee and tabled on the floor, it frequently leads to the release of a substantial amount of information from the executive branch that can alter presidential policy in both military and domestic affairs.
The Perceived Onset Time of Self- and Other-Generated Actions
Authors: Wohlschläger Andreas , Haggard Patrick , Gesierich Benno , Prinz Wolfgang
Published: November 2003

Awareness of actions is partly based on the intentions accompanying them. Thus, the awareness of self- and other-generated actions should differ to the extent that access to own and other's intentions differs. Recent studies have found a brain circuit (the mirrorneuron system) that represents self- and other-generated actions in an integrated fashion. This system does not respond to actions made by nonagents, such as machines. We measured the estimated onset time of actions that subjects either executed themselves or observed being executed by someone else or by a machine. In three experiments, the estimates of the machine actions always differed from those of self- and other-generated actions, whereas the latter two were indistinguishable. Our results are consistent with the view that intentions are attributed to others but not to machines. They also raise the interesting possibility that people attribute intentions to themselves in the same way as they do to others.
Dental erosion and soft drinks: a qualitative assessment of knowledge, attitude and behaviour using focus groups of schoolchildren. A preliminary study
Authors: May J. , Waterhouse P. J.
Published: November 2003

Objectives.  This qualitative study was designed to record the perception by Newcastle children of the influences on their choice of drinks and their knowledge of the dental health problems caused by acidic drinks.

Methods.  Four focus groups, each involving 8 Newcastle schoolchildren (4 boys and 4 girls) formed the basis of the study. Two age groups, 13–14‐year‐olds and 8–9‐year‐olds, and two socio‐economic groups were investigated, using state schools in Newcastle upon Tyne. A moderator guided the children to discuss their choice of drink and its dental effects amongst themselves.

Results.  In total, 32 children participated in the focus groups and the results suggested that 8–9‐year‐olds preferred still, fruit‐flavoured drinks whilst 13–14‐year‐olds preferred carbonated drinks. Taste was the most important influence on drink choice in all age groups. Parents and friends were more influential in younger children, whilst cost, availability and thirst were more important to older children. Younger children did not believe advertisements whilst older children thought they might work if seen enough times. Dental knowledge was confused in all age groups and only the 13–14‐year‐old‐high socio‐economic groups knew that acidic drinks were bad for the teeth. Different methods for addressing the problem of erosion were suggested by different age groups. There was very little difference between the socio‐economic groups in the areas discussed.

Conclusions.  The children's knowledge of dental diseases and the effect of drinks on the teeth were confused. The factors that influence drink choice appear to change with age, rather than socio‐economic status.
Identification and characterization of a Fc Receptor activity on the Toxoplasma gondii tachyzoite
Authors: Vercammen M. , El Bouhdidi A. , Ben Messaoud A. , De Meuter F. , Bazin H. , Dubremetz J.‐F. , Carlier Y.
Published: November 2003

The Immunoglobulin (Ig) binding capacity of Toxoplasma gondii tachyzoites was investigated using fluorescence flow‐cytometry analysis. Polyclonal mouse, human and rat immunoglobulins without specific anti‐Toxoplasma activity bound to parasites in a concentration‐dependent manner, saturating them at circulating serum concentrations. The immunoglobulin class and subclass specificity of binding was investigated using irrelevant monoclonal antibodies. IgM, IgA and IgG reacted with the parasite membrane. The attachment of mouse IgM to the parasite surface was hampered by mouse IgG1, IgG2a, IgG2b and IgG3. The binding of mouse IgG was proportionally reduced with increasing concentrations of mouse monoclonal IgM. The binding of murine immunoglobulin was diminished when in presence of human IgG. Purified Fc‐ but not Fab portions of immunoglobulins, fixed to parasites. Using labelled calibrated beads, the Ig binding capacity of parasites was estimated to be 6900 ± 500 sites per tachyzoite. The Kd of the T. gondii Fc Receptor (FcR) activity was determined at 1.4 ± 0.1 μM (mean ± SEM). Such FcR activity was reduced by phospholipase C, trypsin and pronase treatment of the parasites. These data show a low affinity FcR activity on T. gondii tachyzoites which recognizes Ig of different species and isotypes and is likely supported by a glycosyl‐phosphatidylinositol (GPI)‐anchored surface protein of the parasite.
Effects of phosphate availability on the root system architecture: large‐scale analysis of the natural variation between Arabidopsis accessions
Authors: CHEVALIER F. , PATA M. , NACRY P. , DOUMAS P. , ROSSIGNOL M.
Published: November 2003

Developmental plasticity is one main adaptative response of plants to the availability of nutrients. In the present study, the naturally occurring variation existing in Arabidopsis for the growth responses to phosphate availability was investigated. Initially details of the effects of phosphate starvation for the four currently used accessions Cvi, Col, Ler and Ws were compared. A set of 10 growth parameters, concerning the aerial part and the root system, was measured in both single‐point and time‐course experiments. The length of the primary root and the number of laterals were found to be consistently reduced by phosphate starvation in all four accessions. These two robust parameters were selected to further screen a set of 73 accessions originating from a wide range of habitats. One‐half of the accessions showed also a reduced primary root and less lateral roots when phosphate‐starved, and 25% were not responsive to phosphate availability. For the last quarter of accessions, phosphate starvation was found to affect only one of the two growth parameters, indicating the occurrence of different adaptative strategies. These accessions appear to offer new tools to investigate the molecular basis of the corresponding growth responses to phosphate availability.
Growth hormone therapy before and after pediatric renal transplant
Authors: Acott Philip D. , Pernica Jeffrey M.
Published: November 2003

Abstract:  Children undergoing successful renal transplantation anticipate optimal growth and development. The use of rhGH pre‐ and post‐Tx has been evaluated and supported by randomized control trials. Several strategies are required to maximize the potential benefit of this treatment in the renal population including provision of adequate nutrition intake, following bone parameters with appropriate interventions, and strategies to reduce steroid therapy including utilization of alternate day steroid treatment. Studies are required to further assess the impact of rhGH on renal allograft function, rejection risk, and allograft ultrastructural changes.
Stage IV hepatic encephalopathy associated with acute blindness after liver transplantation
Authors: Arikan Cigdem , Tekgul Hasan , Eğilmez Sait , Kilic Murat , Yagci Rasit V , Tokat Yaman , Aydogdu Sema
Published: November 2003

Abstract:  A 5‐yr‐old boy who diagnosed acute liver failure and Stage IV hepatic encephalopathy underwent living related liver transplantation and awakened with persistent hand motions visual loss. Serum Tacrolimus, electrolytes, magnesium levels were normal as well as blood pressure. His neurologic and opthamologic examinations were otherwise normal. Visual evoked potential (VEP) was prolonged and brain magnetic resonance immaging (MRI) revealed bilateral parietooccipital white matter signal abnormalities with gliosis. During follow up his visual loss resolved spontoneously as well as the VEP and MRI abnormalities. In this case we aimed to point out hepatic encephalopathy might be a cause of postoperative visual loss and serial VEP analysis is an important diagnostic tool for monitoring visual function of liver graft recipients in the post‐operative period.
Association of a putative regulatory polymorphism in the PD‐1 gene with susceptibility to type 1 diabetes
Authors: Nielsen C. , Hansen D. , Husby S. , Jacobsen B.B. , Lillevang S.T.
Published: November 2003

Abstract:  The immunoreceptor programmed cell death‐1 (PD‐1) is reported to play an important role in the regulation of peripheral tolerance in rodents, and it was recently shown that a polymorphism in a regulatory site of the PD‐1 gene is associated with susceptibility to the autoimmune disease systemic lupus erythematosus (SLE) in humans. We investigated the existence of single‐nucleotide polymorphisms (SNPs) in the PD‐1 gene in patients with type 1 diabetes in comparison with healthy control subjects, by analyzing 94 children and adolescents with type 1 diabetes diagnosed before their eighteenth birthday (male : female = 52 : 42) and 155 control subjects. Polymorphisms in the complete PD‐1 gene (minus the large intron 1) were detected by sequencing. In total, we identified 14 SNPs, of which six have been previously described, including an intronic 7146G/A SNP. We found this polymorphism to be associated with the development of type 1 diabetes [found in 12.2% of diabetic individuals vs 6.8% in controls; odds ratio (OR) = 1.92]. The associated allele is previously shown to alter a transcription factor‐binding site (RUNX1/AML1), and the results of this study suggest that this allele could act as an additional susceptibility allele to type 1 diabetes.
Interaction of DAPI with individual strands of trinucleotide repeats
Authors: Trotta Edoardo , Del Grosso Nicoletta , Erba Maura , Melino Sonia , Cicero Daniel , Paci Maurizio
Published: November 2003

The structural changes produced by the minor‐groove binding ligand DAPI (4′,6‐diamidine‐2‐phenylindole) on individual strands of trinucleotide repeat sequences were detected by electrophoretic band‐shift analysis and related to their effects on DNA replication in vitro. Among the 20 possible single‐stranded trinucleotide repeats, only the T‐rich strand of the AAT·ATT triplet exhibits an observable fluorescence band and a change in electrophoretic mobility due to the drug binding. This is attributable to the property of DAPI that favours folding of the random coil ATT strand into a fast‐migrating hairpin structure by a minor‐groove binding mechanism. Electrophoretic characteristics of AAT, ACT, AGT, ATG and ATC are unchanged by DAPI, suggesting the crucial role of T·T with respect to A·A, C·C and G·G mismatch, in favouring the binding properties and the structural features of the ATT–DAPI complexes. Primer extension experiments, using the Klenow fragment of DNA polymerase I, demonstrate that such a selective structural change at ATT targets presents a marked property to stall DNA replication in vitro in comparison with the complementary AAT and a random GC‐rich sequence. The results suggest a novel molecular mechanism of action of the DNA minor‐groove binding ligand DAPI.
Hypertension screening and cardiovascular risk profiling in Vietnam
Authors: Duong Diep N. , Ryan Rebecca , Vo Dai T. , Tran Thuan T.
Published: November 2003

Abstract The purpose of the present descriptive study was to determine the risks associated with hypertension in Vietnamese communities around Ho Chi Minh City, Vietnam. The 357 volunteers for this health promotion screening consisted of 125 men and 232 women, 19–85 years of age. Participants completed surveys on their cardiovascular health history, health practices and hypertension knowledge. Nearly one‐third of the sample was found to have systolic blood pressure (SBP) above 139 mmHg and/or diastolic blood pressure (DBP) above 89 mmHg. Fifteen participants had either SBP over 180 mmHg or DBP over 108 mmHg, nine of these 15 participants were taking antihypertensive drugs and 76 were taking other cardiac medications. The majority (98%) cooked with salt and 75% added salt when eating. Drinking alcohol (21%) and smoking (23%) were more common in male participants. Knowledge of cardiovascular risks was very low, indicating a need for community health promotion activities with educational campaigns and further screenings.
Experimental reconstruction of dog's esophagus with biotype artificial esophagus
Authors: ZHI Fa Chao , ZHANG Lan Jun , PENG Xiu Fan , WU Xiang Hui , PAN De Shou , WAN Tian Mo , LIU Si De , ZHANG Zhen Shu , ZHOU Dian Yuan
Published: November 2003

OBJECTIVE:  At present, there are few materials available for esophagus reconstruction anywhere in the world. The reported survival rate in animals during the perioperative period is comparatively low. The present study assessed the feasibility of using a biotype artificial esophagus in the reconstruction of a dog's esophagus.

METHODS:  In 30 mongrel dogs, a portion of the thoracic esophagus was resected and an 8 cm section of artificial esophagus was transplanted to reconstruct the organ. The survival rate, food intake and process of healing were observed.

RESULTS:  Of the 30 dogs, 28 survived the peri­operative period (93.3% survival). Two dogs (6.7%) developed an anastomotic fistula; 19 dogs survived for 1 year, a survival rate of 79.2% (19/24) with the remaining six dogs were killed according to the experimental protocol. Detachment of the artificial esophagus occurred on average 28.8 days after operation and the dogs suffered from varying degrees of dysphagia 23−45 days after operation. Gradual remission occurred after 4 months. The histological study revealed that the regenerated esophagus was composed of fibrous and connective tissues and the luminal surface was covered with squamous epithelium in 3−6 months.

CONCLUSION:  The transplanted artificial esophagus detached after the surrounding ‘regenerated esophagus’ had formed, and the squamous epithelium gradually covered the luminal surface. Continuous remodeling of the ‘regenerated esophagus’ gradually relieved the stenosis. Whether detachment of the implant and the postoperative stenosis can be solved is the key problem restricting the use of the biotype artificial esophagus in clinical practice.
Markers for dopaminergic neurotransmission in the cerebellum in normal individuals and patients with Parkinson's disease examined by RT‐PCR
Authors: Hurley Michael J. , Mash Deborah C. , Jenner Peter
Published: November 2003

The presence of neuronal elements that are indicative of dopaminergic neurotransmission in cerebellum suggest that this brain region may contribute to the motor symptoms or dyskinesia seen in Parkinson's disease. Reverse transcription polymerase chain reaction (RT‐PCR) was used to examine the expression of markers for dopaminergic neurotransmission in the cerebellum from postmortem brain tissue obtained from normal subjects and patients dying with Parkinson's disease who were receiving treatment with dopaminergic drugs. Dopamine D1−3 receptors, tyrosine hydroxylase and dopamine transporter mRNA was detected in the uvula and nodulus (lobules 9 and 10, respectively) of the vermis of cerebellum from normal individuals. In Parkinson's disease, the level of dopamine D1 and D3 receptor mRNA was significantly reduced in lobule 9 and the level of tyrosine hydroxylase mRNA was significanty reduced in lobule 10. No alteration in the level of dopamine D2 receptor or dopamine transporter mRNA was found in either lobule in patients with Parkinson's disease. These results show that mRNA expression for the functional components of dopaminergic neurotransmission is present in human cerebellum. The discrete changes in the levels of dopamine D1 and D3 receptors and tyrosine hydroxylase mRNA in cerebellum from l‐DOPA treated Parkinson's disease patients suggests that this brain area has a role in the symptoms of Parkinson's disease and/or the beneficial/side‐effects of treatment.
BDNF sensitizes the response of lamina II neurons to high threshold primary afferent inputs
Authors: Garraway Sandra M. , Petruska Jeffrey C. , Mendell Lorne M.
Published: November 2003

Brain‐derived neurotrophic factor (BDNF) is up‐regulated and released in the dorsal horn following peripheral inflammation and has therefore been implicated in spinal mechanisms of sensitization. Despite these observations, the mechanisms associated with such a role for BDNF are not yet fully determined. Here, we investigate the effect of BDNF on dorsal root‐evoked synaptic transmission in lamina II neurons. In a transverse spinal cord slice preparation from neonatal rats (P1–15), the whole cell patch‐clamp technique was used to record from these neurons. Brief application of BDNF (50–200 ng/mL) facilitated the evoked synaptic currents; they remained enhanced even after BDNF was washed out. A significant minority of cells was minimally affected by BDNF and consistent with this, not all neurons in lamina II were immunoreactive for the tyrosine kinase (trk) B receptor. No facilitation was elicited when N‐methyl‐d‐aspartate (NMDA) receptors were blocked with D‐APV, when the postsynaptic NMDA receptors were selectively blocked with intracellular MK‐801, or when postsynaptic neurons were loaded with BAPTA. Additionally, inhibiting phospholipase C (PLC) or protein kinase C (PKC) prior to BDNF application completely blocked facilitation. However, once synaptic current underwent BDNF‐induced facilitation, the PKC inhibitors failed to reverse the effect, suggesting that PKC is needed for initiation, but not maintenance of BDNF‐induced facilitation. These results demonstrate that BDNF functions at the spinal level to enhance synaptic efficacy in an NMDA receptor‐dependent manner and requires the action of the PLC/PKC pathway. This action of BDNF may contribute to central sensitization and exaggerated pain states.
Changes in methylation during progressive transcriptional silencing in transgenic subterranean clover
Authors: Hagan Nicholas D. , Spencer Donald , Moore Andrew E. , Higgins Thomas J. V.
Published: November 2003

A transgenic line of subterranean clover (Trifolium subterraneum) containing a gene for a sulphur‐rich sunflower seed albumin (ssa gene) and a gene conferring tolerance to the herbicide phosphinothricin (bar gene) was previously shown to stably express these genes as far as the T3 generation. In subsequent generations there was a progressive decline in the level of expression of both of these genes such that, by the T7 generation, the plants were almost completely susceptible to the herbicide and the mean level of sunflower seed albumin was reduced to 10–30% of the level in the T2 and T3 generations. The decline in SSA protein correlated closely with a decline in the level of ssa RNA. In vitro transcription experiments with nuclei isolated from plants of the early and late generations showed that the reduced mRNA level was associated with a reduced level of transcription of the ssa transgene. Transcription of the bar transgene was also reduced in the late generations. Bisulphite sequencing analysis showed that the decline in expression of the ssa gene between T3 and subsequent generations correlated closely with increased CpG methylation in the promoter, but not in the coding region. Analysis of the bar gene promoter showed that high levels of CpG methylation preceded the first detectable decline in expression of the bar gene by one generation, suggesting that methylation was not the direct cause of transgene silencing in these plants.
Mergers and Acquisitions in the Private Sector: What Are the Lessons for Health and Social Services?
Authors: Field Janet , Peck Edward
Published: November 2003

In seeking a more seamless provision of health and social care, the government is promoting the merger of the functions of primary and community health services and social services. In the private sector, mergers have been commonplace. The primary aim of this paper is to identify the key concepts and explanatory frameworks in the literature on mergers and acquisitions in the private sector that are relevant to the development of new organizational structures in health and social care. The evidence suggests that it is difficult to merge two organizations successfully. Reasons for this are explored and the implications for health and social care mergers drawn out.
Residence and Migration in Post‐War Soviet Estonia: The Case of Russian‐Born Estonians
Authors: Kulu Hill
Published: November 2003

Conventional research has used aggregate statistics and bivariate methods in studying migration in Soviet society and has stressed the critical role of a single (usually structural) determinant in an individual's migration. This research tests the dominant view, using individual level data and multivariate methods. The objective is to clarify the extent to which structural‐environmental factors and the extent to which personal characteristics determined the first residence and migration of Russian‐born Estonians in post‐war Estonia. The data of the retrospective survey on 265 ethnic Estonians born in Russia between 1915 and 1969 and settled in Estonia between 1940 and 1988 are used. It appears that the first residence and migration of the ethnic Estonians was shaped by an immigration cohort – the variable reflecting structural‐environmental conditions. However, several personal characteristics – age, earlier life‐environment, language usage and education – also turned out to be important determinants of residence and migration of the ethnic Estonians. The results provide evidence to the view that migration in the Soviet Union was a complex outcome of interaction of structural forces and people's preferences, and therefore differed less from other parts of the world than often presumed.
Residential Segregation in a Medium‐Sized Post‐Soviet City: Ust’‐Kamenogorsk, Kazakhstan
Authors: Gentile Michael
Published: November 2003

This paper focuses on the occurrence of ethnic and socio‐economic residential segregation in Ust’‐Kamenogorsk, a medium‐sized city in Kazakhstan, using data collected by the author in collaboration with the Eastern Kazakhstan oblast’ statistical authority in an extensive questionnaire survey carried out during January 2001. Together with the marketisation of the city's housing resources, a number of Soviet legacies, including the major industrial enterprises’ housing strategies for their workers and the city's previous status as ‘closed’, are identified. Finally, the paper maps and analyses existing segregation patterns.
Rudston ‘Cursus A’– Engaging with a Neolithic Monument in Its Landscape Setting Using GIS
Authors: Chapman Henry P.
Published: November 2003

Summary. Cursus monuments are one of the most functionally enigmatic of prehistoric structures. Surrounding Rudston, East Yorkshire, a cluster of at least four cursuses converges on a bend in the Great Wold Valley. Of these monuments, Cursus A, or the ‘Woldgate Cursus’, is particularly unusual, with a curving morphology that forms a ‘dogleg’ plan. The unique shape of this structure provides an opportunity for studying cursus morphology with the aim of interpreting its function – essentially, why does the structure curve in this way? A GIS‐based approach is used which demonstrates a compelling visual relationship between the area enclosed by the cursus and the positions of two long barrows lying on its western horizon. The results of this study are considered in relation to the broader question of cursus function.
Lactate and oxygen constitute a fundamental regulatory mechanism in wound healing
Authors: Trabold Odilo , Wagner Silvia , Wicke Corinna , Scheuenstuhl Heinz , Hussain M. Zamirul , Rosen Noah , Seremetiev Alan , Becker Horst D. , Hunt Thomas K.
Published: November 2003

For many years, lactate has been known to accelerate collagen deposition in cultured fibroblasts and, without detailed explanation, has been presumed to stimulate angiogenesis. Similarly, hypoxia has been linked to angiogenic effects and collagen deposition from cultured cells. Paradoxically, however, wound angiogenesis and collagen deposition are increased by breathing oxygen and decreased by hypoxia. Lactate accumulates to 4–12 mM in wounds for several reasons, only one of which is the result of hypoxia. Oxygen in wounds is usually low but can be increased by breathing oxygen (without change in lactate). We have reported that lactate elicits vascular endothelial growth factor (VECF) from macrophages, as well as collagen, some heat shock proteins, and VECF from endothelial cells, and collagen from fibroblasts, even in the presence of normal amounts of oxygen. Hypoxia exerts many of these same effects in cultured cells. In this study, we elevated extracellular lactate in wounds by implanting purified solid‐state, hydrolysable polyglycolide. A steady‐state 2–3 mM additional elevation of lactate resulted. With it, there was a significant short‐term elevation of interleukin‐1β, a long‐term elevation of VECF (2×) and transforming growth factor‐β1 (2–3×), a 50% elevation in collagen deposition, and a large reduction of insulin‐like growth factor‐1 (− 90%). We propose that lactate induces a biochemical “perception” of hypoxia and instigates several signals that activate growth factor/cytokine signals while the continued presence of molecular oxygen allows endothelial cells and fibroblasts to reproduce and deposit collagen. The data are consistent with ADP‐ribosylation effects and oxidant signaling. (WOUND REP REG 2003;11:504–509)