bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural model and functional significance of pH-dependent talin–actin binding for focal adhesion remodeling
Authors: Srivastava J. , Barreiro G. , Groscurth S. , Gingras A. R. , Goult B. T. , Critchley D. R. , Kelly M. J. S. , Jacobson M. P. , Barber D. L.
Published: September 2008

Actin filament binding by the focal adhesion (FA)-associated protein talin stabilizes cell-substrate adhesions and is thought to be rate-limiting in cell migration. Although F-actin binding by talin is known to be pH-sensitive
in vitro
, with lower affinity at higher pH, the functional significance of this pH dependence is unknown. Because increased intracellular pH (pH
i
) promotes cell migration and is a hallmark of metastatic carcinomas, we asked whether it increases FA remodeling through lower-affinity talin–actin binding. Talin contains several actin binding sites, but we found that only the COOH-terminal USH-I/LWEQ module showed pH-dependent actin binding, with lower affinity and decreased maximal binding at higher pH. Molecular dynamics simulations and NMR of this module revealed a structural mechanism for pH-dependent actin binding. A cluster of titratable amino acids with upshifted pK
a
values, including His-2418, was identified at one end of the five-helix bundle distal from the actin binding site. Protonation of His-2418 induces changes in the conformation and dynamics of the remote actin binding site. Structural analyses of a mutant talin-H2418F at pH 6.0 and 8.0 suggested changes different from the WT protein, and we confirmed that actin binding by talin-H2418F was relatively pH-insensitive. In motile fibroblasts, increasing pH
i
decreased FA lifetime and increased the migratory rate. However, expression of talin-H2418F increased lifetime 2-fold and decreased the migratory rate. These data identify a molecular mechanism for pH-sensitive actin binding by talin and suggest that FA turnover is pH-dependent and in part mediated by pH-dependent affinity of talin for binding actin.
Memory CD8 T cell responses exceeding a large but definable threshold provide long-term immunity to malaria
Authors: Schmidt Nathan W. , Podyminogin Rebecca L. , Butler Noah S. , Badovinac Vladimir P. , Tucker Brad J. , Bahjat Keith S. , Lauer Peter , Reyes-Sandoval Arturo , Hutchings Claire L. , Moore Anne C. , Gilbert Sarah C. , Hill Adrian V. , Bartholomay Lyric C. , Harty John T.
Published: September 2008

Infection of mice with sporozoites of
Plasmodium berghei
or
Plasmodium yoelii
has been used extensively to evaluate liver-stage protection by candidate preerythrocytic malaria vaccines. Unfortunately, repeated success of such vaccines in mice has not translated readily to effective malaria vaccines in humans. Thus, mice may be used better as models to dissect basic parameters required for immunity to
Plasmodium
-infection than as preclinical vaccine models. In turn, this basic information may aid in the rational design of malaria vaccines. Here, we describe a model of circumsporozoite-specific memory CD8 T cell generation that protects mice against multiple
P. berghei
sporozoite challenges for at least 19 months. Using this model we defined a threshold frequency of memory CD8 T cells in the blood that predicts long-term sterilizing immunity against liver-stage infection. Importantly, the number of
Plasmodium
-specific memory CD8 T cells required for immunity greatly exceeds the number required for resistance to other pathogens. In addition, this model allowed us to identify readily individual immunized mice that exceed or fall below the protective threshold before infection, information that should greatly facilitate studies to dissect basic mechanisms of protective CD8 T cell memory against liver-stage
Plasmodium
infection. Furthermore, the extremely large threshold in memory CD8 T cell frequencies required for long-term protection in mice may have important implications for development of effective malaria vaccines.
Use of experimental crystallographic phases to examine the hydration of polar and nonpolar cavities in T4 lysozyme
Authors: Liu Lijun , Quillin Michael L. , Matthews Brian W.
Published: September 2008

There is conflicting evidence as to whether cavities in proteins that are nonpolar and large enough to accommodate solvent are empty or are occupied by disordered water molecules. Here, we use multiple-wavelength x-ray data collected from crystals of the selenomethionine-substituted L99A/M102L mutant of T4 lysozyme to obtain a high-resolution electron density map free of bias that is unavoidably associated with conventional model-based structure determination and refinement. The mutant, L99A/M102L, has four cavities, two being polar in character and the other two nonpolar. Cavity 1 (polar, volume 45.2 Å
3
) was expected to contain two well ordered water molecules, and this is confirmed in the experimental electron density map. Likewise, cavity 2 (polar, 16.9 Å
3
) is confirmed to contain a single water molecule. Cavity 3 (nonpolar, 21.4 Å
3
) was seen to be empty in conventional x-ray refinement, and this is confirmed in the experimental map. Unexpectedly, however, cavity 4 (nonpolar, volume 133.5 Å
3
) was seen to contain diffuse electron density equivalent to ≈1.5 water molecules. Although cavity 4 is largely nonpolar, it does have some polar character, and this apparently contributes to the presence of solvent. The cavity is large enough to accommodate four to five water molecules, and it appears that a hydrogen-bonded chain of three or more solvent molecules could occupy the cavity at a given time. The results are consistent with theoretical predictions that cavities in proteins that are strictly nonpolar will not contain solvent until the volume is large enough to permit mutually satisfying water–water hydrogen bonds.
Development of hippocampal mossy fiber synaptic outputs by new neurons in the adult brain
Authors: Faulkner Regina L. , Jang Mi-Hyeon , Liu Xiao-Bo , Duan Xin , Sailor Kurt A. , Kim Ju Young , Ge Shaoyu , Jones Edward G. , Ming Guo-li , Song Hongjun , Cheng Hwai-Jong
Published: September 2008

New neurons are continuously generated in restricted regions of the adult mammalian brain. Although these adult-born neurons have been shown to receive synaptic inputs, little is known about their synaptic outputs. Using retrovirus-mediated birth-dating and labeling in combination with serial section electron microscopic reconstruction, we report that mossy fiber
en passant
boutons of adult-born dentate granule cells form initial synaptic contacts with CA3 pyramidal cells within 2 weeks after their birth and reach morphologic maturity within 8 weeks in the adult hippocampus. Knockdown of Disrupted-in-Schizophrenia-1 (DISC1) in newborn granule cells leads to defects in axonal targeting and development of synaptic outputs in the adult brain. Together with previous reports of synaptic inputs, these results demonstrate that adult-born neurons are fully integrated into the existing neuronal circuitry. Our results also indicate a role for DISC1 in presynaptic development and may have implications for the etiology of schizophrenia and related mental disorders.
An integrated mechanobiochemical feedback mechanism describes chromosome motility from prometaphase to anaphase in mitosis
Authors: Liu Jian , Desai Arshad , Onuchic José N. , Hwa Terence
Published: September 2008

During mitosis, chromosomes undergo a series of movements while being end-on attached to the kinetochore microtubules (KMTs) from spindle poles. The mechanism underlying such movements and their physiological functions remains elusive. We describe a mechanobiochemical feedback model of chromosome motility. The key ingredient is a feedback mechanism between the local chemical reactions that control the dynamics of KMTs and the mechanical state of the chromosome via tension-sensitive proteins localized at the kinetochores. This model can recapitulate all of the essential and distinct features of chromosome motilities from prometaphase to anaphase in a coherent manner. We further show that this feedback mechanism provides robust and precise means of guiding the chromosome to the cell equator regardless of the initial conditions and uncertainty in velocity. Predictions of our model can be tested experimentally.
Book Review
Authors: Hermann Kirstine Lintrup
Published: September 2008

Direct Diagnosis in Radiology: Urogenital Imaging. First edition. Edited by B. Hamm, P. Asbach, D. Beyersdorff, P. Hein, & U. Lemke. Stuttgart, New York: Thieme Medical Publishers, 2008. ISBN: 978-3-13-145151-4. 251 pages, 233 illustrations. Price (paperback): USD 59.95
Book Review
Authors: Skaane Per
Published: September 2008

The Practice of Breast Ultrasound: Techniques - Findings - Differential Diagnosis. By H. Madjar & E. B. Mendelson. Stuttgart: Georg Thieme Verlag, 2008. ISBN 978-3-13-124342-3. 268 pages. Price (hardcover): EUR 129.95
Short Article: Scene perception and memory revealed by eye movements and receiver-operating characteristic analyses: Does a cultural difference truly exist?
Authors: Evans Kris , Rotello Caren M. , Li Xingshan , Rayner Keith
Published: September 2008

Cultural differences have been observed in scene perception and memory: Chinese participants purportedly attend to the background information more than did American participants. We investigated the influence of culture by recording eye movements during scene perception and while participants made recognition memory judgements. Real-world pictures with a focal object on a background were shown to both American and Chinese participants while their eye movements were recorded. Later, memory for the focal object in each scene was tested, and the relationship between the focal object (studied, new) and the background context (studied, new) was manipulated. Receiver-operating characteristic (ROC) curves show that both sensitivity and response bias were changed when objects were tested in new contexts. However, neither the decrease in accuracy nor the response bias shift differed with culture. The eye movement patterns were also similar across cultural groups. Both groups made longer and more fixations on the focal objects than on the contexts. The similarity of eye movement patterns and recognition memory behaviour suggests that both Americans and Chinese use the same strategies in scene perception and memory.
Short Article: Comparing Two-Digit Numbers: The Importance of being Presented Together
Authors: Ganor-Stern Dana , Pinhas Michal , Tzelgov Joseph
Published: September 2008

The effect of presentation mode on magnitude comparisons of two-digit (2D) numbers was examined using the stimuli set developed by Nuerk, Weger, and Willmes (2001). In Experiment 1, only number pairs from difference decades were presented either simultaneously or sequentially. In the former case there was evidence for the parallel processing of both the units and decades digits and for a components representation, consistent with previous findings. In contrast, in the latter case there was evidence for the processing of mainly the decades digits. In Experiment 2, within-decade number pairs were added to make both digits task relevant. The results from the simultaneous condition were again consistent with a components representation, while results from the sequential presentation were in line with a holistic representation, in line with Zhang and Wang's (2005) research. Results therefore suggest that the processing of 2D numbers depends on the way they are presented.
Activation of the MAPK Module from Different Spatial Locations Generates Distinct System Outputs
Authors: Inder Kerry , Harding Angus , Plowman Sarah J. , Philips Mark R. , Parton Robert G. , Hancock John F.
Published: September 2008

The Ras/Raf/MEK/ERK (MAPK) pathway directs multiple cell fate decisions within a single cell. How different system outputs are generated is unknown. Here we explore whether activating the MAPK module from different membrane environments can rewire system output. We identify two classes of nanoscale environment within the plasma membrane. The first, which corresponds to nanoclusters occupied by GTP-loaded H-, N- or K-Ras, supports Raf activation and amplifies low Raf kinase input to generate a digital ERKpp output. The second class, which corresponds to nanoclusters occupied by GDP-loaded Ras, cannot activate Raf and therefore does not activate the MAPK module, illustrating how lateral segregation on plasma membrane influences signal output. The MAPK module is activated at the Golgi, but in striking contrast to the plasma membrane, ERKpp output is analog. Different modes of Raf activation precisely correlate with these different ERKpp system outputs. Intriguingly, the Golgi contains two distinct membrane environments that generate ERKpp, but only one is competent to drive PC12 cell differentiation. The MAPK module is not activated from the ER. Taken together these data clearly demonstrate that the different nanoscale environments available to Ras generate distinct circuit configurations for the MAPK module, bestowing cells with a simple mechanism to generate multiple system outputs from a single cascade.
Mutation of the Arabidopsis NRT1.5 Nitrate Transporter Causes Defective Root-to-Shoot Nitrate Transport
Authors: Lin Shan-Hua , Kuo Hui-Fen , Canivenc Geneviève , Lin Choun-Sea , Lepetit Marc , Hsu Po-Kai , Tillard Pascal , Lin Huey-Ling , Wang Ya-Yun , Tsai Chyn-Bey , Gojon Alain , Tsay Yi-Fang
Published: September 2008

Little is known about the molecular and regulatory mechanisms of long-distance nitrate transport in higher plants. NRT1.5 is one of the 53 Arabidopsis thaliana nitrate transporter NRT1 (Peptide Transporter PTR) genes, of which two members, NRT1.1 (CHL1 for Chlorate resistant 1) and NRT1.2, have been shown to be involved in nitrate uptake. Functional analysis of cRNA-injected Xenopus laevis oocytes showed that NRT1.5 is a low-affinity, pH-dependent bidirectional nitrate transporter. Subcellular localization in plant protoplasts and in planta promoter-β-glucuronidase analysis, as well as in situ hybridization, showed that NRT1.5 is located in the plasma membrane and is expressed in root pericycle cells close to the xylem. Knockdown or knockout mutations of NRT1.5 reduced the amount of nitrate transported from the root to the shoot, suggesting that NRT1.5 participates in root xylem loading of nitrate. However, root-to-shoot nitrate transport was not completely eliminated in the NRT1.5 knockout mutant, and reduction of NRT1.5 in the nrt1.1 background did not affect root-to-shoot nitrate transport. These data suggest that, in addition to that involving NRT1.5, another mechanism is responsible for xylem loading of nitrate. Further analyses of the nrt1.5 mutants revealed a regulatory loop between nitrate and potassium at the xylem transport step.
Thermoelastic properties of magnesiowüstite, (Mg1−xFex)O: determination of the Anderson–Grüneisen parameter by time-of-flight neutron powder diffraction at simultaneous high pressures and temperatures
Authors: Wood Ian G. , Vočadlo Lidunka , Dobson David P. , Price G. David , Fortes A. D. , Cooper Frances J. , Neale J. W. , Walker Andrew M. , Marshall W. G. , Tucker M. G. , Francis D. J. , Stone H. J. , McCammon C. A.
Published: September 2008

The ability to perform neutron diffraction studies at simultaneous high pressures and high temperatures is a relatively recent development. The suitability of this technique for determiningP–V–Tequations of state has been investigated by measuring the lattice parameters of Mg1−xFexO (x= 0.2, 0.3, 0.4), in the rangeP < 10.3 GPa and 300 <T< 986 K, by time-of-flight neutron powder diffraction. Pressures were determined using metallic Fe as a marker and temperatures were measured by neutron absorption resonance radiography. Within the resolution of the experiment, no evidence was found for any change in the temperature derivative of the isothermal incompressibility, ∂KT/∂T, with composition. By assuming that the equation-of-state parameters either varied linearly or were invariant with composition, the 60 measured state points were fitted simultaneously to aP–V–T–xequation of state, leading to values of ∂KT/∂T= −0.024 (9) GPa K−1and of the isothermal Anderson–Grüneisen parameter δT= 4.0 (16) at 300 K. Two designs of simultaneous high-P/Tcell were employed during this study. It appears that, by virtue of its extended pressure range, a design using toroidal gaskets is more suitable for equation-of-state studies than is the system described by Le Godec, Dove, Francis, Kohn, Marshall, Pawley, Price, Redfern, Rhodes, Ross, Schofield, Schooneveld, Syfosse, Tucker & Welch [Mineral. Mag.(2001),65, 737–748].
Thioredoxin as a fusion tag for carrier‐driven crystallization
Authors: Corsini Lorenzo , Hothorn Michael , Scheffzek Klaus , Sattler Michael , Stier Gunter
Published: September 2008

Structural investigations are frequently hindered by difficulties in obtaining diffracting crystals of the target protein. Here, we report the crystallization and structure solution of the U2AF homology motif (UHM) domain of splicing factor Puf60 fused to Escherichia coli thioredoxin A. Both modules make extensive crystallographic contacts, contributing to a well‐defined crystal lattice with clear electron density for both the thioredoxin and the Puf60‐UHM module. We compare two short linker sequences between the two fusion domains, GSAM and GSPPM, for which only the GSAM‐linked fusion protein yielded diffracting crystals. While specific interdomain contacts are not observed for both fusion proteins, NMR relaxation data in solution indicate reduced interdomain mobility between the Trx and Puf60‐UHM modules. The GSPPM‐linked fusion protein is significantly more flexible, albeit both linker sequences have the same number of degrees of torsional freedom. Our analysis provides a rationale for the crystallization of the GSAM‐linked fusion protein and indicates that in this case, a four‐residue linker between thioredoxin A and the fused target may represent the maximal length for crystallization purposes. Our data provide an experimental basis for the rational design of linker sequences in carrier‐driven crystallization and identify thioredoxin A as a powerful fusion partner that can aid crystallization of difficult targets.
Amino acid composition and protein dimension
Authors: Carugo Oliviero
Published: September 2008

There is indirect evidence that the amino acid composition of proteins depends on their dimension. The amino acid composition of a nonredundant set of about 550,000 proteins was determined and it was observed that, in the range of 50–200 residues, the percentage of occurrence of most of the residue types significantly depends on protein dimension. This result should prove useful in analyzing protein sequences and genomics.
Corm tunic morphology of Turkish Crocoideae (Iridaceae) and their systematic significance
Authors: Erol Osman , Küçüker Orhan , Üzen Erdal
Published: September 2008

The corms of the Crocoideae vary in size, shape, number of internodes and length, the tunic structure of which often supplies good taxonomic characters. We here present detailed corm and tunic drawings and crystal types of Crocus L., Romulea Maratti and Gladiolus L. for the first time. Crocus taxa show tunic characteristics that are significantly different from each other. Romulea shows useful taxonomic characters only on the margins of the tunics that is covering the basal ridge. Tunic characters of the studied Gladiolus species are not as stable as in the other genera. The crystal types of the corm tunics of the studies taxa have been identified in Crocus: typical; small and thin square shaped, relatively short and thick, arrow‐shaped styloids. Romulea has regularly lined, hexagonal crystals on tunics. Gladiolus taxa have typical styloids and crystalline granules.
Experimental reduction of incubation temperature affects both nestling and adult blue tits Cyanistes caeruleus
Authors: Nilsson Johan F. , Stjernman Martin , Nilsson Jan‐Åke
Published: September 2008

Incubation was for a long time considered to be a period of decreased activity and low cost for parents. It was therefore ignored as a potential factor affecting life‐history trade‐offs in birds. Lately this view has started to change, and studies now show that there might be considerable costs connected to incubation. We experimentally reduced the nest temperature during incubation in blue tits Cyanistes caeruleus, thus increasing the energetic cost of incubation, to test the importance of incubation as a component of reproductive costs and for nestling quality. While most other studies use brood size manipulation to manipulate reproductive costs, we were able to separate treatment effects acting during the incubation period from those acting on later reproductive performance by applying a cross‐foster design. We were also able to isolate the effects of decreased incubation temperature on the nestlings from treatment effects acting on incubating females. We found no experimental effect on the length of the incubation period or on hatching success. The lower temperature during incubation, however, caused lower growth rates in nestlings and reduced chick rearing capacity in adults. We conclude that incubation is a costly period, with the potential to affect both the trade‐off between current and future reproduction and the one between parental effort and offspring quality within the current breeding attempt.
Avian predators in a meadow landscape: consequences of their occurrence for breeding open‐area birds
Authors: Van Der Vliet Roland E. , Schuller Edwin , Wassen Martin J.
Published: September 2008

We examined the occurrence of six species of meadow birds (four wader species and two songbird species) in relation to the distance to the nest location of an avian predator (three species). We related our findings to the degree of openness of the landscape in which this avian predator nest was located. The degree of openness varied from very open to very closed, depending on the number of view‐obstructing landscape elements in the landscape (none or very few in open ones, but completely covered with forest or built‐up area in very closed landscapes). We used a dataset containing nesting locations of meadow birds and predators in the province of Gelderland, the Netherlands, allowing us to perform the analysis on three grid cell sizes (100×100 m, 250×250 m and 500×500 m). Our results show that, for each grid cell size, all meadow bird species showed highest nesting densities in open landscapes. Lowered densities were found around occupied nests of avian predators, irrespective whether the predator's nest was situated in an open or closed landscape. The preference of meadow birds for open landscapes away from predator's nests suggests that a large visibility, that allows them to scan for predators to be able to chase them away in time, is an important habitat requirement for meadow birds to select a nest site. It also suggests that openness of the landscape, independent from the presence of occupied predator's nests, is a factor in selecting a nest site. In contrast, for two out of three species of avian predator, we found that they chose more closed landscapes to nest because these species nest in landscape elements like wood lots and lone trees which make the landscape more closed by definition. For the third avian predator species, the grid cell size was probably too small to find a consistent result, as that species has territories larger than even the largest grid cell size we used.
Lack of evidence for improved immune response of extra‐pair nestlings in collared flycatcher Ficedula albicollis
Authors: Wilk Tomasz , Cichoń Mariusz , Wolff Kirsten
Published: September 2008

Extra‐pair paternity is common in many socially monogamous bird species. Increasing evidence suggests that extra‐pair copulations are female‐driven, but benefits for females mating outside social pair‐bonds are still poorly understood. The most influential explanation, “good genes” hypothesis, states that females mated socially with low quality males, engage in extra‐pair copulations to obtain genetic benefits for their progeny. According to this model, enhanced performance of extra‐pair offspring is expected. Here, based on 4‐year study of collared flycatcher Ficedula albicollis, we compared the condition of extra‐pair and within‐pair young. We found no difference in immune response and body size between maternal half‐siblings raised in the same nests. Additionally sex ratio was not biased among extra‐pair nestlings, and paternity was not associated with hatching rank. Our results failed to reveal “good genes” effects in the studied population. These effects might be hard to detect, but other hypotheses should also be studied more thoroughly in the future.
Captive and free‐living red knots Calidris canutus exhibit differences in non‐induced immunity that suggest different immune strategies in different environments
Authors: Buehler Deborah M. , Piersma Theunis , Irene Tieleman B.
Published: September 2008

Experiments on captive animals, in which conditions can be controlled, are useful for examining complex biological phenomena such as immune function. Such experiments have increased our understanding of immune responses in the context of trade‐offs and pathogen pressure. However, few studies have examined how captivity itself affects immune function. We used microbial killing, leukocyte concentrations and complement‐natural antibody assays to examine non‐induced (constitutive) immunity in captive and free‐living red knots Calidris canutus. Univariate and multivariate analyses indicated that captive and free‐living birds differed in their immune strategies. Captive birds showed reduced S. aureus killing, C. albicans killing, heterophils, and eosinophils. In a principal component analysis, the affected variables fell onto a single axis, that reflected phagocytosis and inflammation based immunity. We discuss possible reasons for this result in an immune cost and protective benefit framework.
Mitochondrial DNA data imply a stepping‐stone colonization of Beringia by arctic warbler Phylloscopus borealis
Authors: Reeves Andrew B. , Drovetski Sergei V. , Fadeev Igor V.
Published: September 2008

Arctic warbler Phylloscopus borealis is one of several high‐latitude Passerines which are widely distributed across one northern continent but restricted to the Beringian part of the other. Most species with such asymmetric intercontinental ranges are monomorphic across Beringia, suggesting either recent colonization of the second continent or considerable gene flow across the Bering Strait. Arctic warbler is the only migratory species in this group that has three different subspecies in Beringia: Ph. b. borealis (Scandinavia to western Beringia, south to Mongolia), Ph. b. xanthodryas (Japan, Sakhalin, Kamchatka, western Beringia), and Ph. b. kennicotti (Alaska). This polymorphism may indicate that Arctic warbler has a unique and complex phylogeographic history that differs significantly from other species with similar ranges. Our analyses of complete mtDNA ND2 sequences of 88 Arctic warblers collected across the species range showed that the clade comprised of birds breeding on Sakhalin Island and Kamchatka Peninsula diverged from the Palearctic/Beringian clade by 3.8% in ND2 sequence. Beringian birds formed a recently derived clade embedded within the Palearctic clade. Nucleotide diversity declined sharply eastward from Palearctic to western Beringia and then to eastern Beringia. Our data provided no support for currently recognized subspecies. They suggested that the barrier at the western edge of Beringia was crossed by Arctic warbler earlier than the Bering Strait resulting in a stepping‐stone colonization of Beringia by this species. Gene flow appears to be restricted across the western border of Beringia but not the Bering Strait.
Service user experience of participation in child welfare case management
Authors: Tregeagle Susan , Mason Jan
Published: September 2008

Child welfare case management systems were designed, in part, to standardize participatory practices for both young people and their parents. This paper reports the findings of a qualitative study of Australian service users' experiences of participation when using the case management systems, Looking After Children and Supporting Children and Responding to Families. Findings indicate that the majority of service users reported positive experiences of participating in the use of these systems. However, participatory relations were often slow to develop and frequently involved conflict. Some service users used their power to control the flow and accuracy of information, or resisted workers in other ways. Some children and young people were excluded from the opportunity to participate because the systems did not have a ‘text‐based’ format to ‘ensure’ that this process occurred. These findings indicate that case management systems did not result in relationships which consistently informed the intervention in a way that the systems' authors had envisaged. Service users did not necessarily take up the openings offered to them and workers did not necessarily comply with the systems' obligations. The findings cause us to question the assumptions that power can be bestowed or withdrawn, in the way suggested by these case management systems.
Fostering self‐esteem: exploring adult recollections on the influence of foster parents
Authors: Luke Nikki , Coyne Sarah M.
Published: September 2008

Foster parents are in a unique position to improve the self‐esteem of children in their care, which may be lower than that of their non‐fostered peers. According to Harter's dual‐influence model, both general support or attachment and domain‐specific support contribute to self‐esteem. The current study used this model to explore the ways in which foster parents had influenced the self‐esteem of a sample of five adults with differing foster care experiences. Retrospective interviews were used to gather memories of high self‐esteem from time spent in foster care. A thematic analysis of the interview transcripts supported Harter's model, and provided a number of examples of ways in which foster parents could boost children's self‐esteem. The model was further extended to show the importance of ‘normality’ and inclusion for this sample of fostered adults. Further research on this topic is recommended with a view to widening the scope of foster carer training beyond attachment theory.
Mealtime interaction patterns between young children with cerebral palsy and their mothers: characteristics and relationship to feeding impairment
Authors: Veness C. , Reilly S.
Published: September 2008

Background  A significant proportion of children with cerebral palsy have some degree of feeding impairment, which not only affects their ability to obtain adequate nourishment, but may also impinge on their ability to interact with their mothers during mealtimes. The quality of the maternal–child interaction may also be affected by the mealtime being prolonged and/or stressful. Patterns of interaction between mothers and their children with cerebral palsy have typically been described in play situations. There is limited information about interaction during mealtimes. The purpose of this study therefore, was to observe and describe the characteristics of mealtime interaction between mothers and their young children with cerebral palsy, and to determine whether feeding impairment and other sample characteristics were related to interaction patterns.

Methods  The participants were 20 mothers and their children with cerebral palsy. Physical, cognitive, and feeding abilities varied. Video recordings of each mother–child dyad interacting during a typical mealtime were analysed in order to describe the structure of the interaction, the communicative functions used, and what method the children used to communicate. The characteristics of the interaction were summarized and compared and the relationship between feeding ability and other child factors and interaction patterns were explored.

Results  Results revealed that interactions were maternally dominated. Mothers produced most of the communicative behaviour during the mealtime and used more directive functions than their children. The severity of feeding impairment was related to child patterns of interaction, but not to maternal interaction patterns. Language delay was also related to interaction patterns.

Conclusions  The results of this study highlight the importance for professionals to consider mealtime interactions for children with cerebral palsy and their mothers as an integral part of feeding investigations and ongoing interventions, as feeding impairment does seem to have a bearing on aspects of interaction.
22q11.2 deletion syndrome: behaviour problems of children and adolescents and parental stress
Authors: Briegel W. , Schneider M. , Schwab K. Otfried
Published: September 2008

Background  22q11.2 deletion syndrome can be associated with a variety of somatic symptoms, developmental delays and psychiatric disorders. At present, there is little information on behaviour problems, parental stress and possible relations between these factors. Therefore, this study investigates behaviour problems of children and adolescents with 22q11.2DS, and their primary caregivers’ stress.

Methods  Parents of 4–17 year old subjects known to the German 22q11.2 deletion syndrome foundation were anonymously asked to fill out several questionnaires, e.g. the Child Behavior Checklist 4–18 (CBCL/4–18).

Results  The primary caregivers of 77/126 children [43 males, 34 females, mean age: 8;0 (4;0–16;11) years] sent back filled‐out questionnaires. Forty‐six of 76 subjects were rated as clinical on at least one of the CBCL‐scales. Males had significantly higher scores on the total problems scale and the internalizing problems scale than females. The patients’ age correlated with several CBCL‐scales. Eleven of 49 subjects were suspicious of an autism spectrum disorder. Compared with the general population, but not with other parents of mentally and/or physically handicapped children, the primary caregivers experienced higher levels of stress, but showed normal life satisfaction.

Conclusions  In spite of high rates of clinical behaviour problems among children and adolescents with 22q11.2DS and despite increased parental stress, most primary caregivers seem to have effective coping strategies, e.g. partnership support, to sustain normal levels of life satisfaction.
Information needs in parents of children with a rheumatic disease
Authors: Thon A. , Ullrich G.
Published: September 2008

Background and Objective  Incorporating the patient's perspective and expectations into the delivery of health care has become an important indicator of today's quality of medical care. Our aim was consequently to explore the information needs of parents of children with juvenile idiopathic arthritis and other rheumatic diseases.

Materials and Methods  Cross‐sectional, anonymous survey using a purpose‐designed questionnaire, which separately assessed sources of information and topics. With respect to sources, we also asked about their degree of helpfulness, and regarding topics, we also asked about further interests (information needs). The questionnaire was sent to 146 families continuously attending our paediatric rheumatology outpatient clinic. The response rate was 79.5%. The mean age of the children was 6.9 ± 4.3 years, 69% were girls and disease duration averaged 2.6 ± 4.3 years. Mean Child Health Assessment Questionnaire score as a measure of functional disability was 0.259 (±0.45; range 0.0–2.13).

Results  Regarding sources, those with a professional medical background were appreciated, while information from friends and family members, in particular, was not. Overall, parents considered themselves well‐informed. Parents had frequently received information on core domains of medical aspects. They described deficits related to psychosocial impact, to (vocational) education and to complementary therapy. However, their interest in further information was high almost irrespective of the amount of prior information.

Conclusion  For further tailored information and support strategies it should be taken into account that even for topics largely covered by usual medical advice, residual interest and information needs of parents remain high.
Genetic screening of a Dutch population with isolated GH deficiency (IGHD)
Authors: De Graaff Laura C. G. , Argente Jesús , Veenma Danielle C. M. , Herrebout Maaike A. C. , Friesema Edith C. H. , Uitterlinden André G. , Drent Madeleine L. , Campos‐Barros Ángel , Hokken‐Koelega Anita C. S.
Published: September 2008

Objective  Five per cent to 30% of cases of idiopathic isolated GH deficiency (IGHD) have first‐degree relatives with short stature, which is suggestive of a genetic aetiology. The HYPOPIT study aimed to obtain an overall picture of gene encoding pituitary GH (GH1) and gene encoding GH releasing hormone‐receptor (GHRHR) defects in a Dutch IGHD cohort and to relate them with clinical parameters.

Design, patients and measurements  Genetic analysis was performed of exons and exon–intron boundaries of GH1 and GHRHR in 89 Caucasian IGHD patients from 81 families, using denaturing high‐performance liquid chromatography (dHPLC), DNA sequencing and multiplex ligation‐dependent probe amplification. In addition, we performed functional studies on novel identified GH1 exonic variants.

Results  Five different heterozygous GH1 mutations were present in 5 out of 81 participating families (6·1%), whereas no mutations in GHRHR were found. Patients with IGF‐I SDS < –4·0 and peak GH levels < 5·7 mU/l had a mutation frequency of 40%, in contrast to 6·8% in patients with only one criterion, and 0·0% in patients with none of these criteria (P = 0·00007). Five new GH1 and two GHRHR variants were also identified; two of them (GH1 F92L and D153H) caused a marked reduction of GH secretion in vitro.

Conclusion  GH1 and GHRHR mutations are rare in Caucasian Dutch IGHD patients, which suggests the involvement of other genetic determinants in the aetiology of IGHD. IGF‐I < –4·0 and peak GH levels < 5·7 mU/l are strong predictors of GH1 mutations in the studied population.
Scale‐dependent effects of fine sediments on temperate headwater invertebrates
Authors: LARSEN S. , VAUGHAN I. P. , ORMEROD S. J.
Published: September 2008

1. Anthropogenic activities can increase fine sediment supply to streams over multiple spatial and temporal extents. Identifying the processes responsible, and the scale at which any effects on stream organisms become evident, are key management needs, but appropriately scaled surveys are surprisingly few.

2. We surveyed macroinvertebrates and superficial fine sediments at two spatial resolutions (reach‐ and patch‐scale) in tributaries of the River Usk, a temperate, montane catchment in rural Wales (U.K.). Land use, habitat and geomorphological character were measured on‐site or derived from an existing database (=Fluvial Audit). We aimed to identify: (i) how in‐stream sediments varied with land use and associated geomorphology; (ii) likely consequences for macroinvertebrates and (iii) any scale‐dependence in relationships between macroinvertebrates and sediment character.

3. At both the reach‐ and patch‐scales, bed cover by fine sediment was related directly to the extent of eroding banks 500 m upstream. In turn, sedimentation and bank erosion were negatively correlated with catchment or riparian woodland extent.

4. At the reach scale, macroinvertebrate composition varied with catchment land use and stream chemistry, with richness declining as rough grazing or woodland was replaced by improved grassland. There was no response to deposited sediment except for weak increase in the relative abundance of oligochaetes.

5. By contrast, at the patch scale, fine sediments were accompanied by pronounced changes in invertebrate composition, and we ranked the 27 most common taxa according to their apparent sediment tolerance. General estimating equations showed that total and Ephemeroptera, Plecoptera and Trichoptera richness decreased significantly by 20% and 25% at the most sediment impacted sites (30% cover) by comparison with sediment‐free sites.

6. We conclude that sediment deposition in the upper Usk system mostly reflects local bank erosion, with riparian woodland likely to mediate this process through bank stability. Fine sediment release had marked ecological effects, but these were detectable only at patch‐to‐patch scales. We suggest that investigation of localized sediment release in streams will benefit from scale‐dependent or scale‐specific sampling, and some effects could go undetected unless sample resolution is selected carefully.
Assessing the sources and magnitude of diurnal nitrate variability in the San Joaquin River (California) with an in situ optical nitrate sensor and dual nitrate isotopes
Authors: PELLERIN BRIAN A. , DOWNING BRYAN D. , KENDALL CAROL , DAHLGREN RANDY A. , KRAUS TAMARA E. C. , SARACENO JOHNFRANCO , SPENCER ROBERT G. M. , BERGAMASCHI BRIAN A.
Published: September 2008

1. We investigated diurnal nitrate (NO3−) concentration variability in the San Joaquin River using an in situ optical NO3− sensor and discrete sampling during a 5‐day summer period characterized by high algal productivity. Dual NO3− isotopes (δ15NNO3 and δ18ONO3) and dissolved oxygen isotopes (δ18ODO) were measured over 2 days to assess NO3− sources and biogeochemical controls over diurnal time‐scales.

2. Concerted temporal patterns of dissolved oxygen (DO) concentrations and δ18ODO were consistent with photosynthesis, respiration and atmospheric O2 exchange, providing evidence of diurnal biological processes independent of river discharge.

3. Surface water NO3− concentrations varied by up to 22% over a single diurnal cycle and up to 31% over the 5‐day study, but did not reveal concerted diurnal patterns at a frequency comparable to DO concentrations. The decoupling of δ15NNO3 and δ18ONO3 isotopes suggests that algal assimilation and denitrification are not major processes controlling diurnal NO3− variability in the San Joaquin River during the study. The lack of a clear explanation for NO3− variability likely reflects a combination of riverine biological processes and time‐varying physical transport of NO3− from upstream agricultural drains to the mainstem San Joaquin River.

4. The application of an in situ optical NO3− sensor along with discrete samples provides a view into the fine temporal structure of hydrochemical data and may allow for greater accuracy in pollution assessment.
Effectiveness of different gutta‐percha techniques when filling experimental internal resorptive cavities
Authors: Gencoglu N. , Yildirim T. , Garip Y. , Karagenc B. , Yilmaz H.
Published: September 2008

Aim  To determine the quality of root fillings in teeth with artificial internal resorptive cavities filled with Thermafil, JS Quick‐Fill, Soft Core, System B and Microseal, and by cold lateral compaction (LC) technique.

Methodology  Sixty maxillary incisor teeth were selected. After access cavity preparation and root canal instrumentation, the roots were sectioned horizontally and artificial internal resorption cavities were prepared on the canal walls. The tooth sections were cemented together and the root canals were filled using one of six different techniques: Thermafil, JS Quick‐Fill, Soft Core, System B and Microseal, and by LC. The roots were then divided at the level of the previous section and each root surface was photographed. Image analysis program was used to calculate the percentage of sealer, gutta‐percha and void in the internal resorptive cavities. All measurements were analysed statistically using One‐way anova and Newman–Keuls tests.

Results  The Microseal technique filled 99% of the artificial resorptive area followed by LC (92%), SystemB (89%), Quick‐Fill (88%), Thermafil (74%) and Soft‐Core (73%). Warm gutta‐percha compaction techniques filled the resorption areas with more gutta‐percha than sealer (Microseal 68%, System B 62%) compared to the other techniques (LC 48%, Quick Fill 41%, Soft Core 34%, Thermafil 35%). In addition, core techniques left a considerable volume of voids in the resorptive areas (Quick‐Fill 12%, Thermafil 26%, Soft Core 27%).

Conclusions  Warm gutta techniques filled artificial resorption cavities significantly better than the other gutta‐percha techniques.
Nutritional potential and functional properties of tempe produced from mixture of different legumes. 1: Chemical composition and nitrogenous constituent
Authors: Nassar Ahmad G. , Mubarak Adel E. , El‐Beltagy Alaa E.
Published: September 2008

Fermented foods such as Tempe represent a technological alternative for a great variety of legumes and combination of them to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. The chemical composition, carbohydrate fraction and nitrogenous constituents were investigated for individual different legumes, i.e. faba bean; lupine, chickpea; peas and their mixture before and after fermentation by Rhizopus oligosporus. Tempe had a higher (P < 0.05) protein and fibre content compared with legume mixtures before fermentation, while it had a lower fat, ash and carbohydrate contents. Also, reducing and non‐reducing sugars, stachyose as well as raffinose were reduced after fermentation of legume mixtures. A significant reduction was observed in non‐protein nitrogen and protein nitrogen, while total nitrogen and true protein were increased.
Effect of domestic cooking on the red cabbage hydrophilic antioxidants
Authors: Podsędek Anna , Sosnowska Dorota , Redzynia Małgorzata , Koziołkiewicz Maria
Published: September 2008

The contents of vitamin C, total phenolics, anthocyanins, hydroxybenzoic and hydroxycinnamic acids as well as 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) monocation radical scavenging activity were evaluated in two varieties of red cabbage before and after conventional and steam‐cooking. During the conventional cooking 32.7–64.5% of vitamin C and 45.7–66.9% of total phenolics were retained in cooked tissue. Decreasing cooking water volume by half led to better retention of both phenolics (by 2.7–14.5%) and vitamin C (by 14.2–18.4%). However, shortening the cooking time by half affected the retention of phenolics and vitamin C only by 3.8–6.7% and 0–2.2%, respectively. Steam‐cooking is recommended to prevent the major loss of scavenging activity, because under these conditions, the corresponding TEAC (Trolox Equivalent Antioxidant Capacity) values were reduced only by 5–20%. Moreover, the content of vitamin C was decreased by 2.1–22.7% while losses of total phenolics were up to 10%. The phenolics are the major source of free radical scavenging activity of red cabbage, since the contribution of vitamin C to TEAC for fresh and cooked red cabbage was from 18.2 to 28.5%.
Effect of regular and hydrolysed dairy proteins on texture, microstructure and colour of lean poultry meat batters
Authors: Barbut Shai
Published: September 2008

The use of 2% milk protein isolate (MPI), and some of its fractions which included caseinate, whey protein isolate (WPI), two whey protein hydrolysates (5.2% and 8.5%; WPH‐I and WPH‐II respectively) and β‐lactoglobulin (β‐lac) was evaluated in lean chicken breast meat batters. Adding caseinate and MPI resulted in the highest fracture force values, and caseinate also provided higher yield compared with the control. Both proteins were observed to form distinct protein islands embedded within the meat protein matrix, which appeared to enhance the gel structure. The two hydrolysates provided the highest yield compared with all other treatments. However, adding WPH‐II also resulted in the lowest fracture force and hardness values, while WPH‐I provided similar values to the control. The low hardness value could be explained by the light micrograph which showed WPH‐II interfering with the binding of the meat proteins. The WPI and β‐lac provided similar yield, fracture and hardness values as the control. The colour of the products was most affected by the WHP‐I and WHP‐II; both resulted in lower lightness, yellowness and overall spectra reflectance curves. A cost analysis revealed that caseinate addition was the most economical in this lean meat system.