bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of an altered protective effect of metallothioneins after cadmium exposure in the digenean parasite-infected cockle (Cerastoderma edule)
Authors: BAUDRIMONT M. , de MONTAUDOUIN X.
Published: October 2006

The aim of the present study was to analyse the relation between parasitism and subsequent metallothioneins (MT) in the case of metal contamination. Experimental exposure of parasitized and unparasitized cockles (Cerastoderma edule) to cadmium (Cd) was performed, with the cockle as first or second intermediate host of 2 digenean species. After 7 days of Cd exposure in microcosms, cockles infected as first intermediate host byLabratrema minimusexhibited metal concentrations in tissues double that in uninfected cockles. Jointly, MT concentrations of parasitized cockles were not modified in comparison with uninfected individuals in which concentrations were increased 4·3-fold compared with controls. In cockles experimentally infected as the second intermediate host byHimasthla elongata, cadmium concentrations significantly increased again in parasitized cockles compared with uninfected individuals in contaminated conditions. Simultaneously, MT concentrations in healthy cockles increased, whereas they significantly decreased in parasitized individuals. Therefore, the presence of digenean parasites in Cd-exposed cockles leads to a maintenance or a decrease in MT concentrations compared with healthy individuals, whereas Cd accumulation in tissues is significantly increased. These experiments indicate a significant alteration of the protective effect of metallothioneins towards metals which could consequently enhance cockle vulnerability. Moreover, these results highlight the limit of the use of MT as a biomarker of metal pollution in field monitoring if parasitism is not taken into account.
Mitochondrial genomes of parasitic arthropods: implications for studies of population genetics and evolution
Authors: SHAO R. , BARKER S. C.
Published: October 2006

Over 39000 species of arthropods parasitize humans, domestic animals and wildlife. Despite their medical, veterinary and economic importance, most aspects of the population genetics and evolution of the vast majority of parasitic arthropods are poorly understood. Mitochondrial genomes are a rich source of markers for studies of population genetics and evolution. These markers include (1) nucleotide sequences of each of the 37 mitochondrial genes and non-coding regions; (2) concatenated nucleotide sequences of 2 or more genes; and (3) genomic features, such as gene duplications, gene rearrangements, and changes in gene content and secondary structures of RNAs. To date, the mitochondrial genomes of over 700 species of multi-cellular animals have been sequenced entirely, however, only 24 of these species are parasitic arthropods. Of the mitochondrial genome markers, only the nucleotide sequences of 4 mitochondrial genes,cox1,cob,rrnSandrrnL, have been well explored in population genetic and evolutionary studies of parasitic arthropods whereas the sequences of the other 33 genes, and various genomic features have not. We review current knowledge of the mitochondrial genomes of parasitic arthropods, summarize applications of mitochondrial genes and genomic features in population genetic and evolutionary studies, and highlight prospects for future research.
When perception isn't reality: Accent identification and perceptual dialectology in French
Authors: BOUGHTON ZOË
Published: October 2006

This article examines levelling and diversity in northern urban French pronunciation through the optic of folk (= non-linguists') perceptions of variation. These perceptions are investigated by the identification of authentic voice samples (rather than other instruments widely used in perceptual dialectology such as mental mapping): respondents from the Pays de la Loire region of north-western France heard extracts of scripted speech from Nancy and Rennes, and were asked to identify the speakers' regional background and say whether they were of urban or rural origin. The results of this test show that while some difference between the two speaker location groups was accurately perceived, the informants also formed some inaccurate judgements, partly based on social stereotypes. Overall there is some confirmation of accent levelling, and of general social psychological tendencies such as stereotyping, annexation and time-lag in perceptions of regional–social linguistic variation.
Archaeology, hermeneutics of suspicion and phenomenological trivialization
Authors: Olsen Bjørnar
Published: October 2006

The point of departure for this debate (and the SAA forum) was the question ‘does archaeological theory exist?’ Matthew Johnson's answer is wisely mixed, but mostly negative. Archaeological theory does not exist, he tells us, because there is hardly any distinctive archaeological way of theoretical thinking ‘to which most or even the largest group of archaeologists would willingly or knowingly subscribe’ (p. 117). I shall not spend much time on Johnson's denial, which for several reasons may well be justified, just note that if we apply his rather rigorous consensual criterion to other disciplines, we would probably be searching in vain also for any sociological, economic or even philosophical theory – which Johnson still seems quite convinced do exist.
Colony or conflict zone?
Authors: Scham Sandra
Published: October 2006

Audrey Horning has a lot to say about the abuses of overarching theory in archaeology. Her most cogent critiques, directed at the rather careless application of postcolonial theory to the archaeology of Northern Ireland and the failure of that theoretical model to deal effectively with the complex and fragmented identities of this continually embattled society, spoke powerfully to my own experience. The intellectual currency of colonialism and postcolonialism is becoming as rapidly devalued as that of domination and resistance. This is not to say these concepts have no merit – only that they suffer from overuse and a persistent lack of nuanced examination.
On being heard. Theory as an archaeological practice
Authors: Tomášková Silvia
Published: October 2006

Suggesting that archaeological theory both exists and does not at the same time is a wise move, so long as it opens the possibility for a range of answers and dialogue. In that respect I find myself in an agreement with Johnson, given that he takes up a piece of the theoretical minefield, and leaves plenty for others to engage with. Rather than debate his argument per se, therefore, I will endeavour to enlarge his essay in ways that will both contrast my position with his and further a greater conversation.
Archaeology and theoretical culture
Authors: Johnson Matthew H.
Published: October 2006

First, a qualifier: the ‘response-to-the-response’ section of Archaeological dialogues is often the most entertaining part of the issue, but frequently the least intellectually rewarding. One feels Schadenfreude, partisan cheering and jeering, and bafflement in equal measure as contributors lock horns over this or that finer point of who has misrepresented whom. I am anxious to avoid readers reacting to what follows in such a manner, and so will concentrate on a very selective range of raised points that, to put it crudely, got me thinking.
Accurate estimates of the spatial pattern of denudation by inversion of stacking velocity data: An example from the British Isles
Authors: Mackay L. M. , White N. J.
Published: October 2006

Accurate measurement of the temporal and spatial variation of uplift and denudation would improve our understanding of the way in which mountain building and mantle convection modify the Earth's surface. Here, we show that inverse modeling of stacking velocity data from seismic reflection data sets is a potentially useful tool for obtaining spatially resolved denudation estimates along and across continental shelves. Unlike many techniques for measuring denudation, our approach is not restricted to outcrop or borehole locations, although it is important to calibrate results with other measurements of denudation. We have inverted 2200 stacking velocity analyses from a dense network of two‐dimensional seismic reflection lines which surround the British Isles. This region was chosen because there is a well‐known signal of Cenozoic uplift and denudation which is big enough to be detectable using our approach. Despite simplified assumptions about the way in which porosity varies with depth, our offshore denudation estimates are consistent with outcrop patterns and accord with published denudation measurements. Furthermore, stacking velocity estimates agree with measurements obtained by analyzing sonic velocity logs from selected boreholes. A region encompassing the British Isles has evidently undergone variable amounts of denudation during Cenozoic times. However, significant denudation (>1.5 km) is concentrated in discrete areas, such as off NW Scotland and parts of the Irish Sea. The magnitude of denudation changes significantly over short (∼10 km) distances, implying that differential uplift and erosion have been important factors in creating the present‐day denudation pattern.
Evidence for coeval Late Triassic terrestrial impacts from the Rochechouart (France) meteorite crater
Authors: Carporzen Laurent , Gilder Stuart A.
Published: October 2006

High temperature impact melt breccias from the Rochechouart (France) meteorite crater record a magnetization component with antipodal, normal and reverse polarities. The corresponding paleomagnetic pole for this component lies between the 220 Ma and 210 Ma reference poles on the Eurasian apparent polar wander path, consistent with the 214 ± 8 Ma 40Ar/39Ar age of the crater. Late Triassic tectonic reconstructions of the Eurasian and North American plates place this pole within 95% confidence limits of the paleomagnetic pole from the Manicouagan (Canada) meteorite impact crater, which is dated at 214 ± 1 Ma. Together, these observations reinforce the hypothesis of a Late Triassic, multiple meteorite impact event on Earth.
Optimization of Cardiac Resynchronization Therapy by Continuous Hemodynamic Monitoring:
Authors: BRAUNSCHWEIG FRIEDER , KJELLSTRÖM BARBRO , GADLER FREDRIK , LINDE CECILIA
Published: October 2006

We report the case of a 55‐year‐old male patient with severe congestive heart failure in whom both a hemodynamic monitor and a biventricular pacemaker were implanted. The potential usefulness of the monitor to optimize AV delay and heart rate was prospectively evaluated. The AV delay associated with the lowest filling pressures recorded by the monitor was similar to the optimal AV delay as determined by standard echocardiography. Heart rates >70 beats/min acutely improved hemodynamics but were not tolerated when programmed chronically. This case illustrates that continuous hemodynamic monitoring may offer a useful tool for device tuning and treatment monitoring in cardiac resynchronization therapy. (J Cardiovasc Electrophysiol, Vol. 15, pp. 94‐96, January 2004)
Atrial Tachyarrhythmia Recurrence Temporal Patterns in Bradycardia Patients Implanted with Antitachycardia Pacemakers
Authors: RICCI RENATO , SANTINI MASSIMO , PADELETTI LUIGI , BORIANI GIUSEPPE , CAPUCCI ALESSANDRO , BOTTO GIANLUCA , GULIZIA MICHELE , INAMA GIUSEPPE , GALATI ANTONIO , SOLIMENE FRANCESCO , PEPE MASSIMILANO , GRAMMATICO ANDREA
Published: October 2006

Introduction: New‐generation pacemakers allow continuous atrial tachyarrhythmia (AT) monitoring that provides accurate information about AT type, frequency, burden, and temporary evolution.

Methods and Results: We performed a prospective multicenter study to describe AT temporal patterns in patients with sinus bradycardia and AT. Two hundred forty patients (123 men; age 71 ± 8 years) were implanted with a DDDRP pacemaker (model AT500, Medtronic Inc.). All patients were followed for 13 months. The first‐month stabilization period of all patients was discarded from analysis. Seventy percent of patients had AT recurrences. Mean time to first AT recurrence (48.2 days, 95% confidence interval [CI] 37.0–59.5 days) was significantly longer than the time between first and second AT episode (10.3 days, 95% CI 6.7–13.9 days, P < 0.01). A minority of patients had a uniform time distribution of AT recurrences: <25% of patients had AT episodes in more than 6 of the 12 months considered in the study. The probability density function of consecutive sinus rhythm days between AT episodes was calculated for each of 40 patients who experienced >25 AT episodes and fitted by power law and exponential functions. The best fit was obtained by power law function in 60% of patients, by exponential function in 10%, and the two models gave comparable results in 30% of patients.

Conclusion: In our population of patients with a history of sinus bradycardia and AT who were implanted with a new device equipped with atrial pacing therapies, 30% did not experience AT recurrences in the 12‐month study period. Analysis of interevent time showed that in 60% of patients AT recurrences do not follow a uniform or random distribution. These findings bring into question the use of cross‐over design and time to first AT recurrence as a clinical outcome in trials for AT therapy in this patient population. (J Cardiovasc Electrophysiol, Vol. 15, pp. 44‐51, January 2004)
Catheter Ablation of Frequently Recurring Ventricular Fibrillation in a Patient after Aortic Valve Repair
Authors: LI YI‐GANG , GRÖNEFELD GERIAN , ISRAEL CARSTEN , HOHNLOSER STEFAN H.
Published: October 2006

It has been demonstrated that idiopathic ventricular fibrillation (VF) can be triggered by ventricular premature beats (VPBs) arising from the Purkinje fibers. Eliminating these VPBs by radiofrequency catheter ablation prevented VF recurrences. Whether the same pathophysiology and the same treatment option exist in patients with structural heart disease is unknown. Recurrent VF was observed in a 17‐year‐old patient after aortic valve repair of a perforated noncoronary cusp with resulting severe aortic regurgitation. VF recurred despite therapy with various antiarrhythmic drugs. A maximum of 14 external defibrillations was necessary during a 24‐hour period to stabilize the patient. Due to increasing hemodynamic instability as a result of this electrical storm, the patient was referred for invasive diagnostics. During electrophysiologic study, frequent short runs of VF initiated by VPB with a narrow QRS complex were observed. After extensive mapping of the right and left ventricles, two distinct sources of VPBs originating from anteroseptal and inferoseptal areas of the left ventricle could be successfully ablated. VPBs were preceded by distinct Purkinje potentials with intervals from the Purkinje potential to QRS onset of VPB of 68 ms and 30 ms at effective sites, respectively. During short‐term follow‐up of 2 months, there was no VF recurrence. VPB originating from the Purkinje system may be one possibility for VF initiation in patients with structural heart disease. Eliminating these sources of VPBs by catheter ablation can prevent recurrent VF in such patients. (J Cardiovasc Electrophysiol, Vol. 15, pp. 90‐93, January 2004)
Cosmic Ray Anisotropy Studies with a Small Air Shower Array
Authors: Smith A. G. K. , Clay R. W.
Published: October 2006

A small cosmic ray extensive air shower (EAS) array for anisotropy studies has
been built and operated in the southern hemisphere for a full year. The
operation of such an array is discussed as a possible prototype for a
multiarray system which would be simple and reliable to operate. Data from the
array are presented to add to the sparse southern hemisphere data set below
energies of about 1 PeV.
Tunnelling in the Presence of an Environment: Insights from the Fusion of Heavy Nuclei
Authors: Rowley Neil
Published: October 2006

A great many physical processes are mediated by the penetration or surmounting
of a potential barrier. Some notable examples are the thermionic emission of
electrons, chemical reactions, tunnelling of Cooper pairs through Josephson
junctions, nuclear ‘burning’ in stars etc. Often the potential in
question is not simply a function of the position of the intruding particle,
but is a complicated landscape determined by the static structure of the
physical objects concerned as well as by their dynamical response to their
mutual interactions. For example, in a Josephson junction, the penetration of
the barrier is strongly influenced by the excitation of lattice vibrations
while catalysed chemical reactions proceed via complex routes which present a
series of lower activation energies.
In a physical system with a well-defined temperature, the details of the
potential landscape may be obscured by the Maxwell-Boltzmann distribution of
energies. The fusion of heavy nuclei can, however, be achieved over a
controlled range of well-defined beam energies to reveal fine details of some
of these effects. To date the major new experimental work in this area has
been performed at the ANU, Canberra and at the INFN, Legnaro. As well as
yielding valuable information on nuclear structure (detailed information on
nuclear shapes etc.) and some totally unexpected reaction dynamics (complexity
of the induced surface oscillations, neutron flow), these experiments and
their theoretical analysis give considerable insights into the general problem
of ‘tunnelling in the presence of an environment’.
Space Weather, SuperDARN and the Tasmanian Tiger
Authors: Greenwald Raymond A.
Published: October 2006

The plasma environment extending from the solar surface through interplanetary
space to the outermost reaches of the Earth’s atmosphere and magnetic
field is dynamic, often disturbed, and capable of harming humans and damaging
manmade systems. Disturbances in this environment have been identified as
space weather disturbances. At the present time there is growing interest in
monitoring and predicting space weather disturbances. In this paper we present
some of the difficulties involved in achieving this goal by comparing the
processes that drive tropospheric-weather systems with those that drive
space-weather systems in the upper atmosphere and ionosphere. The former are
driven by pressure gradients which result from processes that heat and cool
the atmosphere. The latter are driven by electric fields that result from
interactions between the streams of ionised gases emerging from the Sun (solar
wind) and the Earth’s magnetosphere. Although the dimensions of the
Earth’s magnetosphere are vastly greater than those of tropospheric
weather systems, the global space-weather response to changes in the solar
wind is much more rapid than the response of tropospheric-weather systems to
changing conditions. We shall demonstrate the rapid evolution of space-weather
systems in the upper atmosphere through measurements with a global network of
radars known as SuperDARN. We shall also describe how the SuperDARN network is
evolving, including a newly funded Australian component known as the Tasman
International Geospace Environmental Radar (TIGER).
Ansa-metallocene polymerization catalysts derived from [2+2]cycloaddition reactions of bis(1-methylethenyl-cyclopentadienyl)zirconium systems
Authors: Paradies Jan , Kehr Gerald , Fröhlich Roland , Erker Gerhard
Published: October 2006

Bis(1-methylethenyl-cyclopentadienyl)zirconium dichloride (7a) was prepared by a fulvene route. Photolysis at 0°C with Pyrex-filtered UV light resulted in a rapid and complete intramolecular [2+2]cycloaddition reaction to yield the corresponding cyclobutylene-bridgedansa-zirconocene dichloride isomer (8a). This is one of the rare examples of an organic functional group chemistry that leads to carbon–carbon coupling at the framework of an intact sensitive group 4 bent metallocene complex. More sterically hindered open metallocenes that bear bulky isopropyl ortert-butyl substituents at their Cp rings in addition to the active 1-methylethenyl functional group undergo the photochemicalansa-metallocene ring closure reaction equally facile. The metallocene systems used and obtained in this study have served as transition metal components for the generation of active metallocene propene polymerization catalysts.
Cyclic esters and cyclodepsipeptides derived from lactide and 2,5-morpholinediones
Authors: Chisholm Malcolm H. , Gallucci Judith C. , Yin Hongfeng
Published: October 2006

The reaction between Bu
n
Li in benzene and the solid polystyrene support PS-C
6
H
4
CH
2
NH
2
leads to a lithiated species that can be represented as PS-C
6
H
4
CH
2
NHLi(LiBu)

x

, where
x
∼ 4, which is active in the ring-opening of the cyclic esters
L
-lactide,
rac
-lactide, and 2,5-morpholinediones. With ≈10 eq of these monomeric six-membered rings and with heating, cyclic esters (MeCHC(O)O)

n

and [MeCHC(O)OCHRC(NH)O]

n

are reversibly released to the solution. These have been characterized by electrospray ionization MS, and some small rings have been separated by gel-permeation chromatography. Addition of NaBPh
4
to a heated benzene solution containing these rings preferentially removes the 18-membered rings from solution. For lactide this is shown to form the basis for chemical amplification from a dynamic combinatorial library and lactide can be converted to (MeCHC(O)O)
6
in >80% yield. Metallated supports derived from Me
2
Mg and Et
2
Zn are less reactive but do show some ability for lactide ring-enlarging. The 18-membered ring (
R
,
R
,
R
,
S
,
S
,
S
)- and
meso
-(
R
,
S
,
R
,
S
,
R
,
S
)-(MeCHC(O)O)
6
and the 24-membered ring (MeCHC(O)OCHPr
i
C(NH)O)
4
have been characterized by single-crystal x-ray diffraction studies, together with the complex Na[η
3
-
S
,
S
,
S
,
S
,
S
,
S
-(MeCHC(O)O)
6
]
2
BPh
4
.
Diversin regulates heart formation and gastrulation movements in development
Authors: Moeller Heinz , Jenny Andreas , Schaeffer Hans-Joerg , Schwarz-Romond Thomas , Mlodzik Marek , Hammerschmidt Matthias , Birchmeier Walter
Published: October 2006

Canonical and noncanonical Wnt signaling regulate crucial events in the development of vertebrates and invertebrates. In this work we show that vertebrate Diversin, a potential orthologue of
Drosophila
Diego, controls fusion of heart precursors and gastrulation movements in zebrafish embryogenesis. These events are regulated by noncanonical Wnt signaling, which is independent of β-catenin. We found that Diversin directly interacts with Dishevelled and that this interaction is necessary and sufficient to mediate signals of the noncanonical Wnt pathway to downstream effectors like Rho family GTPases and Jun N-terminal kinase. The ankyrin repeats of Diversin are required for the interaction with Dishevelled, for the activation of noncanonical Wnt signaling, and for the biological responses. The mutation K446M in the DEP domain of vertebrate Dishevelled, which mimics a classical
Drosophila
loss of function mutation, prevents functional interaction with Diversin's ankyrin repeats. Diversin also affects planar cell polarity in
Drosophila
, which is controlled by the noncanonical Wnt signaling pathway. Our data thus demonstrate that Diversin and Dishevelled function together in a mutually dependent fashion in zebrafish gastrulation and organ formation.
Comprehensive genetic selection revealed essential bases in the peptidyl-transferase center
Authors: Sato Neuza Satomi , Hirabayashi Naomi , Agmon Ilana , Yonath Ada , Suzuki Tsutomu
Published: October 2006

During protein synthesis, the ribosome catalyzes peptide-bond formation. Biochemical and structural studies revealed that conserved nucleotides in the peptidyl-transferase center (PTC) and its proximity may play a key role in peptide-bond formation; the exact mechanism involved remains unclear. To more precisely define the functional importance of the highly conserved residues, we used a systematic genetic method, which we named SSER (systematic selection of functional sequences by enforced replacement), that allowed us to identify essential nucleotides for ribosomal function from randomized rRNA libraries in
Escherichia coli
cells. These libraries were constructed by complete randomization of the critical regions in and around the PTC. The selected variants contained natural rRNA sequences from other organisms and organelles as well as unnatural functional sequences; hence providing insights into the functional roles played by these essential bases and suggesting how the universal catalytic mechanism of peptide-bond formation could evolve in all living organisms. Our results highlight essential bases and interactions, which are shaping the PTC architecture and guiding the motions of the tRNA terminus from the A to the P site, found to be crucial not only for the formation of the peptide bond but also for nascent chain elongation.
Cell-specific expression and pathway analyses reveal alterations in trauma-related human T cell and monocyte pathways
Authors: Laudanski Krzysztof , Miller-Graziano Carol , Xiao Wenzhong , Mindrinos Michael N. , Richards Daniel R. , De Asit , Moldawer Lyle L. , Maier Ronald V. , Bankey Paul , Baker Henry V. , Brownstein Bernard H. , Cobb J. Perren , Calvano Steve E. , Davis Ronald W. , Tompkins Ronald G. ,   Inflammation and Host Response to Injury Large-Scale Collaborative Research Program*
Published: October 2006

Monitoring genome-wide, cell-specific responses to human disease, although challenging, holds great promise for the future of medicine. Patients with injuries severe enough to develop multiple organ dysfunction syndrome have multiple immune derangements, including T cell apoptosis and anergy combined with depressed monocyte antigen presentation. Genome-wide expression analysis of highly enriched circulating leukocyte subpopulations, combined with cell-specific pathway analyses, offers an opportunity to discover leukocyte regulatory networks in critically injured patients. Severe injury induced significant changes in T cell (5,693 genes), monocyte (2,801 genes), and total leukocyte (3,437 genes) transcriptomes, with only 911 of these genes common to all three cell populations (12%). T cell-specific pathway analyses identified increased gene expression of several inhibitory receptors (PD-1, CD152, NRP-1, and Lag3) and concomitant decreases in stimulatory receptors (CD28, CD4, and IL-2Rα). Functional analysis of T cells and monocytes confirmed reduced T cell proliferation and increased cell surface expression of negative signaling receptors paired with decreased monocyte costimulation ligands. Thus, genome-wide expression from highly enriched cell populations combined with knowledge-based pathway analyses leads to the identification of regulatory networks differentially expressed in injured patients. Importantly, application of cell separation, genome-wide expression, and cell-specific pathway analyses can be used to discover pathway alterations in human disease.
DASS: efficient discovery andp-value calculation of substructures in unordered data
Authors: Hollunder Jens , Friedel Maik , Beyer Andreas , Workman Christopher T. , Wilhelm Thomas
Published: October 2006

Motivation: Pattern identification in biological sequence data is one of the main objectives of bioinformatics research. However, few methods are available for detecting patterns (substructures) in unordered datasets. Data mining algorithms mainly developed outside the realm of bioinformatics have been adapted for that purpose, but typically do not determine the statistical significance of the identified patterns. Moreover, these algorithms do not exploit the often modular structure of biological data.

Results: We present the algorithm DASS (Discovery of All Significant Substructures) that first identifies all substructures in unordered data (DASSSub) in a manner that is especially efficient for modular data. In addition, DASS calculates the statistical significance of the identified substructures, for sets with at most one element of each type (DASSPset), or for sets with multiple occurrence of elements (DASSPmset). The power and versatility of DASS is demonstrated by four examples: combinations of protein domains in multi-domain proteins, combinations of proteins in protein complexes (protein subcomplexes), combinations of transcription factor target sites in promoter regions and evolutionarily conserved protein interaction subnetworks.

Availability: The program code and additional data are available at

Contact:  wilhelm@fli-leibniz.de

Supplementary information: Supplementary information is available at Bioinformatics online.
Cyanobacterial ecotypes in the microbial mat community of Mushroom Spring (Yellowstone National Park, Wyoming) as species-like units linking microbial community composition, structure and function
Authors: Ward David M , Bateson Mary M , Ferris Michael J , Kühl Michael , Wieland Andrea , Koeppel Alex , Cohan Frederick M
Published: October 2006

We have investigated microbial mats of alkaline siliceous hot springs in Yellowstone National Park as natural model communities to learn how microbial populations group into species-like fundamental units. Here, we bring together empirical patterns of the distribution of molecular variation in predominant mat cyanobacterial populations, theory-based modelling of how to demarcate phylogenetic clusters that correspond to ecological species and the dynamic patterns of the physical and chemical microenvironments these populations inhabit and towards which they have evolved adaptations. We show that putative ecotypes predicted by the theory-based model correspond well with distribution patterns, suggesting populations with distinct ecologies, as expected of ecological species. Further, we show that increased molecular resolution enhances our ability to detect ecotypes in this way, though yet higher molecular resolution is probably needed to detect all ecotypes in this microbial community.
All Parents Are to Blame (Except This One): Global Versus Specific Attitudes Related to Parental Responsibility Laws1
Authors: Brank Eve M. , Hays Stephanie A. , Weisz Victoria
Published: October 2006

Increasing state legislation and media interest give the appearance of public support for parental responsibility laws; however, some national polls suggest otherwise. Based on disparate global and specific attitudes in other areas of the criminal justice literature, it was hypothesized that relatively weak global support for parental responsibility would be diminished even more if a specific juvenile was described. The current studies confirmed that participants were even less supportive of parental responsibility laws when a specific juvenile and his parents were described than they were when they answered questions about parents in general.
Environmental and Family Associations With Racism1
Authors: Smith Shannon Toney , Ross Lisa Thomson
Published: October 2006

Environmental and family factors related to racism in college students were investigated. Students (N=114) at a southern liberal‐arts college filled out an extensive survey about childhood activities and family of origin, and 40 of their mothers completed a similar survey. The Attitudes Toward Blacks (Brigham, 1993) scale measured racism. Several hypotheses were supported. Students who exhibited less racism also reported that they made more diverse friends in school, came from a more diverse hometown, had diverse encounters and friendships at an earlier age, and had more positive foreign travel experiences. In addition, more racist students perceived their mothers as being more prejudiced while they were growing up, and they perceived their fathers as being more prejudiced currently. Finally, students judged their mothers as less racist than their fathers, and also reported that their mothers exhibited less racist behaviors than did their fathers. The importance of racially diverse experiences and friendships early in life are discussed as means to decrease racism.
Social influences and self‐efficacy as predictors of youth smoking initiation and cessation: a 3‐year longitudinal study of vocational high school students in Taiwan
Authors: Chang Fong‐Ching , Lee Ching‐Mei , Lai Hsiang‐Ru , Chiang Jeng‐Tung , Lee Pi‐Hsia , Chen Wen‐Jau
Published: October 2006

Aims  This 3‐year longitudinal study examined changes in patterns of risk factors and protective factors of smoking initiation and cessation among vocational high school students in Taipei, Taiwan.

 Design and setting  In 2000, a total of 2151 10th grade students from 16 vocational high schools were assessed and followed up in the 11th and 12th grades. Self‐administered questionnaires were collected in each year to assess the pattern of changes in smoking behaviors, and risk and protective factors.

Findings  Of the 1654 non‐smokers in the 10th grade, 227 students initiated smoking by the 12th grade. Higher risk factors such as peer smoking, peers offering cigarettes, alcohol use and lower protective factors, such as refusal self‐efficacy, antismoking attitude and belief in the 10th grade predicted youth initiation by grade 12. Increases in risk factors and decreases in protective factors during the years from 10th to 12th grades were associated significantly with youth smoking initiation. Of the 494 smokers in the 10th grade, 76 students quit smoking by the 12th grade. Lower risk factors and higher protective factors in 10th grade smokers predict youth smoking cessation by grade 12. Decreases in risk factors and increases in protective factors were associated significantly with youth smoking cessation.

Conclusions  The risk factors (i.e. social influences) and protective factors (i.e. self‐efficacy) examined in this study predict both youth smoking initiation and youth smoking cessation.
Expression analyses and transcriptional regulation of mouse nucleolar spindle‐associated protein gene in erythroid cells: essential role of NF‐Y
Authors: Fujiwara Tohru , Harigae Hideo , Okitsu Yoko , Takahashi Shinichiro , Yokoyama Hisayuki , Yamada Minami F , Ishizawa Kenichi , Kameoka Junichi , Kaku Mitsuo , Sasaki Takeshi
Published: October 2006

Nucleolar spindle‐associated protein (NuSAP), a recently characterised microtubule‐associated protein, appears to participate in cell cycle regulation. It has been demonstrated that NuSAP is expressed preferentially in the erythroid lineage in haematopoietic cells. To characterise its role in erythropoiesis, we examined the expression profile of the NuSAP gene. In fractionated murine erythroblasts, NuSAP mRNA was remarkably more abundant in the subset corresponding to immature erythroblasts (TER119+CD71high) than mature erythroblasts (TER119+CD71low), and it was significantly increased in TER119+ cells from in vivo phlebotomised mice compared with control mice. Furthermore, during erythroid maturation of mouse erythroleukaemia (MEL) cells by dimethylsulfoxide, NuSAP mRNA was increased at 24–72 h. These results suggested that the NuSAP gene might contribute to the expansion of immature erythroblast pool. The regulatory mechanism of NuSAP gene was investigated using MEL cells. Sequence analysis revealed that NuSAP promoter has four CCAAT boxes, an Sp1 element, a GATA‐like element, a CACCC element, a Myb element and lacks a TATA box. Promoter analyses demonstrated that duplicated CCAAT boxes located at −81/−85 and −30/−34 were essential for promoter activity. Furthermore, the promoter was trans‐activated by NF‐YA through these elements. These results suggest that NuSAP might play an important role in erythroid proliferation under the control of NF‐Y.
Nicotinamide (vitamin B3) increases the polyploidisation and proplatelet formation of cultured primary human megakaryocytes
Authors: Giammona Lisa M. , Fuhrken Peter G. , Papoutsakis Eleftherios T. , Miller William M.
Published: October 2006

Megakaryocytic (Mk) cell maturation involves polyploidisation, and the number of platelets produced increases with Mk DNA content. Ploidy levels in cultured human MK cells are much lower than those observed in vivo. This study demonstrated that adding the water‐soluble vitamin nicotinamide (NIC) to mobilised peripheral blood CD34+ cells cultured with thrombopoietin (Tpo) more than doubled the percentage of high‐ploidy (≥8N) MK cells. This was observed regardless of donor‐dependent differences in Mk differentiation. Furthermore, MK cells in cultures with NIC were larger, had more highly lobated nuclei, reached a maximum DNA content of 64N (vs. 16N with Tpo alone), and exhibited more frequent and more elaborate cytoplasmic extensions. NIC also increased the ploidy of cultured primary murine MK cells and a cell line model (CHRF‐288) of Mk differentiation. However, NIC did not alter Mk commitment, apoptosis, or the time at which endomitosis was initiated. Despite the dramatic phenotypic differences observed with NIC addition, gene expression microarray analysis revealed similar overall transcriptional patterns in primary human Mk cultures with or without NIC, indicating that NIC did not disrupt the normal Mk transcriptional program. Elucidating the mechanisms by which NIC increases Mk maturation could lead to advances in the treatment of Mk and platelet disorders.
Coupling of growth rate and body stoichiometry in Daphnia: a role for maintenance processes?
Authors: KYLE MARCIA , ACHARYA KUMUD , WEIDER LAWRENCE J. , LOOPER KAREN , ELSER JAMES J.
Published: October 2006

1. The growth rate hypothesis predicts positive relationships among growth rate (μ), body RNA (%RNA of dry mass) and body P (%P of dry mass) contents.

2. We tested this within‐ and across‐species by growing five species/clones of Daphnia (Daphnia magna, Daphnia pulex, Daphnia galeata and two isolates of Daphnia pulicaria) with different combinations of food quantity and stoichiometric food quality.

3. Within each species, positive correlations among μ, %RNA and %P were seen and across species there was a strong association between%RNA and %P, consistent with the growth rate hypothesis. However, coupling of growth to %RNA and to %P differed for different species. In particular, the %RNA–μ and %P–μ relationships had similar slopes but considerably different y‐intercepts (i.e.%P or %RNA at zero growth), with D. pulicaria and D. galeata having higher intercepts than D. magna and especially D. pulex. As a result of these displacements, the relative rankings of the species on the basis of %P and %RNA did not correspond to their rankings based on μ.

4. These findings suggest that within a narrow clade (e.g. the daphnids), interspecific differences in body P content may reflect not growth rate‐related RNA allocation but instead the amount of RNA required for support of maintenance processes.
Nursing home care: whodunit?
Authors: Paulus Aggie TG , Van Raak Arno JA , Keijzer Femke B
Published: October 2006

Aims and objectives.  (1) To analyse and compare (changes and differences in) activity profiles of various types of nursing home care. (2) To assess the impact of integrated care on these activity profiles.

Background.  Because of an ongoing introduction of integrated nursing home care, caregivers increasingly have to co‐ordinate their activities, engage into interprofessional relationships and take over each other's tasks. Consequently, activity profiles [i.e. combinations of (contributions to) care activities and the roles that perform them] are expected to change.

Design/methods.  At three measurement points in the period 1999–2003, caregivers (in 18 different roles) recorded and listed direct and indirect care activities. A total of 41 335 lists were analysed to derive activity profiles of traditional, transitional and integrated nursing home care in the Netherlands.

Results.  Traditional, transitional and integrated care shared some comparable activity profiles. Integrated care differed from the other types with respect to the contribution of the geriatric nurse, recreational activities supervisor, nutrition assistant, household assistant and nursing assistant to activities such as extra care, handling food and club activities. Contrary to the other roles, the licensed practical nurse contributed to (almost) all activities in all types of care.

Conclusions.  Nursing home care has several recurring activity profiles. These profiles are the same in all types of nursing home care. The introduction of integrated care implies that particular profiles have to be added to these profiles. As a generalist, the licensed practical nurse seems to play a key role in all activity profiles.

Relevance to clinical practice.  Because of demographic and financial pressures, integrated care for older people becomes increasingly important. By addressing the impact of integrated care on activity profiles, this paper provides information on how new types of care can be delivered in the most effective manner.
Amodiaquine resistance is not related to rare findings of pfmdr1 gene amplifications in Kenya
Authors: Holmgren Gabrielle , Björkman Anders , Gil José Pedro
Published: October 2006

Objectives  Many countries are now adopting artemisinin‐based combination therapy (ACT) for treatment of Plasmodium falciparum malaria. In multi‐drug resistant areas in South East Asia amplifications of the pfmdr1 gene are frequent and tentatively associated with reduced susceptibility to the common quinoline partner drugs mefloquine and lumefantrine. In Africa where amodiaquine is one of the favoured quinoline partner drugs in ACT, studies on multi‐drug resistance associated pfmdr1 gene amplifications are urgent. Our aim was to determine the current prevalence of pfmdr1 gene amplifications and a possible association between pfmdr1 gene copy number and amodiaquine treatment outcome in Kenya.

Methods  Seventy‐two children with Plasmodium falciparum infection in Kenya were treated with amodiaquine monotherapy and followed for 21 days. Possible amplification of the pfmdr1 gene was assessed from blood‐spotted filterpaper by TaqMan® probe based real‐time polymerase chain reaction.

Results  The recrudescent rate was 14 of 72 (19%). All children had single pfmdr1 copy infections, with the exception of one child who had an infection with two pfmdr1 copies. This child had an adequate treatment response.

Conclusion  Pfmdr1 amplifications do exist in Kenya but at a very low frequency. Yet, the substantial number of children with recrudescent infections implies that amodiaquine resistance is not related to pfmdr1 gene amplifications in Kenya.
Segmental haemangiomas of infancy: A review of 14 cases
Authors: Phan Tai Anh , Adams Susan , Wargon Orli
Published: October 2006

Haemangiomas of infancy are the commonest benign tumour in childhood, with the majority being a localized subtype, only requiring therapy in specific locations. The segmental subtype, however, confers a higher complication rate, an association with the PHACE syndrome and poorer prognosis. This retrospective case series of 14 infants with segmental haemangiomas aimed to further define the variety of clinical presentations, complication rates, and response to treatment in this subset of patients. We found in our series that 71% of infants with segmental haemangiomas develop at least one complication related to the lesion. Systemic corticosteroids prevented the further growth as well as reduced the pain and ulceration of the segmental haemangiomas in all of those treated. Early recognition and early treatment to arrest the growth of segmental haemangiomas will reduce morbidity and complications associated with these haemangiomas. Corticosteroid use, however, needs to be considered against the high incidence of side‐effects such as secondary hypertension (40%), cushingoid features (40%) and growth suppression (67%). In our experience, these infants benefit from multidisciplinary team involvement for the assessment of associated syndromes, and to follow up and avoid complications associated with systemic therapy.
Prurigo pigmentosa
Authors: Shannon John F , Weedon David , Sharkey Michael P
Published: October 2006

A 22‐year‐old Chinese woman presented with a 5‐year history of an intensely pruritic eruption on her posterior neck, mid back and sacrum leaving reticulate pigmentation. The diagnosis of prurigo pigmentosa was made on the basis of the clinico‐histological features and a response to minocycline. Although prurigo pigmentosa is uncommon, it has characteristic clinical and histological features. Early diagnosis and appropriate treatment result in a rapid response and prevents a progression of pigmentation.
Cheilitis caused by contact allergy to anethole in spearmint flavoured toothpaste
Authors: Poon Terence SC , Freeman Susanne
Published: October 2006

A 63‐year‐old woman presented with a 6‐year history of persistent cheilitis. Minimal improvement was achieved with therapeutic measures. Patch testing was positive to anethole, a flavouring used in her toothpaste. Her cheilitis resolved after cessation of the flavoured toothpaste. This case demonstrates the importance of considering contact allergy to toothpaste flavours in patients with cheilitis.
Parvovirus B19 infection presenting as ‘bathing trunk’ erythema with pustules
Authors: Butler Gregory J , Mendelsohn Shevaun , Franks Andrea
Published: October 2006

A 7‐year‐old girl presented with acute vulval erythema and pustules, associated with a petechial eruption in her flexures and over her feet. There was a mild prodromal illness and the patient was afebrile. There were minimal symptoms associated with the rash. Skin and throat swabs were negative and blood examination showed mild neutrophilia and lymphopaenia. Parvovirus B19 IgM was detected on serology and cutaneous features resolved within 4 days. This is a further case of parvovirus B19 infection presenting as a ‘bathing trunk’ exanthem that has unique dermatologic features, including the presence of pustules and distant petechiae.
The Management of Refractory Status Epilepticus: An Update
Authors: Lowenstein Daniel H.
Published: October 2006

Summary:  Refractory status epilepticus (RSE) is an important and serious clinical problem that typically requires prolonged and high‐level intensive care, and is often associated with poor outcome. This review addresses some of the current issues concerning the management of RSE, including recent definitions used for clinical studies, epidemiology, clinical course, and outcome. Current approaches to treatment, including the now relatively standard use of intravenous anesthetic agents, as well as emerging therapies utilizing drugs such as valproate and topiramate, are discussed as well.