bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping dynamic memories of gradually changing objects
Authors: Preminger Son , Blumenfeld Barak , Sagi Dov , Tsodyks Misha
Published: March 2009

Our brain is able to maintain a continuously updated memory representation of objects despite changes in their appearance over time (aging faces or objects, growing trees, etc.). Although this ability is crucial for cognition and behavior, it was barely explored. Here, we investigate this memory characteristic using a protocol emulating face transformation. Observers were presented with a sequence of faces that gradually transformed over many days, from a known face (source) to a new face (target), in presentations separated by other stimuli. This practice resulted in a drastic change in the memory and recognition of the faces. Although identification of the source and older face instances was reduced, recent face instances were increasingly identified as the source and rated as highly similar to the memory of the source. Using an object perturbation method, we estimated the corresponding memory shift, showing that memory patterns shifted from the source neighborhood toward the target. Our findings suggest that memory is updated to account for object changes over time while still keeping associations with past appearances. These experimental results are broadly compatible with a recently developed model of associative memory that assumes attractor dynamics with a learning rule facilitated by novelty, shown to hold when objects change gradually over short timescales.
Hepatitis C virus NS2 is a protease stimulated by cofactor domains in NS3
Authors: Schregel V. , Jacobi S. , Penin F. , Tautz N.
Published: March 2009

Chronic infection with hepatitis C virus (HCV) affects 130 million people worldwide and is a major cause of liver cirrhosis and liver cancer. After translation of the HCV RNA genome into a polyprotein, 2 viral proteases process its non-structural protein (NS) region. While the essential chymotrypsin-like serine protease NS3–4A mediates all cleavages downstream of NS3, the NS2–3 cysteine protease catalyzes a vital cleavage at the NS2/3 site. Protease activity of NS2–3 has been described to require, besides NS2, the N-terminal 181 aa of NS3. The latter domain corresponds to the NS3 serine protease domain and contains a structural Zn
2+
-binding site with functional importance for both viral proteases. The catalytic triad of the NS2–3 protease resides in NS2; the role of the NS3 part in proteolysis remained largely undefined. Here we report a basal proteolytic activity for NS2 followed by only 2 amino acids of NS3. Basal activity could be dramatically enhanced by the NS3 Zn
2+
-binding domain (NS3 amino acids 81–213) not only
in cis
but also
in trans
which, however, required a more extended N-terminal part of NS3 downstream of NS2
in cis
. Thus, this study defines for the first time (i) NS2 as a bona fide protease, (ii) NS3 as its regulatory cofactor, and (iii) functional subdomains in NS3 that cooperate in NS2 protease activation. These findings give new mechanistic insights into function and regulation of the NS2 protease and have important implications for the development of anti-HCV therapeutics.
Inhibition of Myc-induced cell transformation by brain acid-soluble protein 1 (BASP1)
Authors: Hartl Markus , Nist Andrea , Khan M. Imran , Valovka Taras , Bister Klaus
Published: March 2009

Cell transformation by the Myc oncoprotein involves transcriptional activation or suppression of specific target genes with intrinsic oncogenic or tumor-suppressive potential, respectively. We have identified the
BASP1
(
CAP-23
,
NAP-22
) gene as a novel target suppressed by Myc. The acidic 25-kDa BASP1 protein was originally isolated as a cortical cytoskeleton-associated protein from rat and chicken brain, but has also been found in other tissues and subcellular locations.
BASP1
mRNA and protein expression is specifically suppressed in fibroblasts transformed by the v-
myc
oncogene, but not in cells transformed by other oncogenic agents. The
BASP1
gene encompasses 2 exons separated by a 58-kbp intron and a Myc-responsive regulatory region at the 5′ boundary of untranslated exon 1. Bicistronic expression of
BASP1
and v-
myc
from a retroviral vector blocks v-
myc
-induced cell transformation. Furthermore, ectopic expression of
BASP1
renders fibroblasts resistant to subsequent cell transformation by v-
myc
, and exogenous delivery of the
BASP1
gene into v-
myc
-transformed cells leads to significant attenuation of the transformed phenotype. The inhibition of v-
myc
-induced cell transformation by BASP1 also prevents the transcriptional activation or repression of known Myc target genes. Mutational analysis showed that the basic N-terminal domain containing a myristoylation site, a calmodulin binding domain, and a putative nuclear localization signal is essential for the inhibitory function of BASP1. Our results suggest that down-regulation of the
BASP1
gene is a necessary event in
myc
-induced oncogenesis and define the BASP1 protein as a potential tumor suppressor.
Ruling out and ruling in neural codes
Authors: Jacobs Adam L. , Fridman Gene , Douglas Robert M. , Alam Nazia M. , Latham Peter. E. , Prusky Glen T. , Nirenberg Sheila
Published: March 2009

The subject of neural coding has generated much debate. A key issue is whether the nervous system uses coarse or fine coding. Each has different strengths and weaknesses and, therefore, different implications for how the brain computes. For example, the strength of coarse coding is that it is robust to fluctuations in spike arrival times; downstream neurons do not have to keep track of the details of the spike train. The weakness, though, is that individual cells cannot carry much information, so downstream neurons have to pool signals across cells and/or time to obtain enough information to represent the sensory world and guide behavior. In contrast, with fine coding, individual cells can carry much more information, but downstream neurons have to resolve spike train structure to obtain it. Here, we set up a strategy to determine which codes are viable, and we apply it to the retina as a model system. We recorded from all the retinal output cells an animal uses to solve a task, evaluated the cells' spike trains for as long as the animal evaluates them, and used optimal, i.e., Bayesian, decoding. This approach makes it possible to obtain an upper bound on the performance of codes and thus eliminate those that are insufficient, that is, those that cannot account for behavioral performance. Our results show that standard coarse coding (spike count coding) is insufficient; finer, more information-rich codes are necessary.
Metalloporphyrins, used for HO‐1 Inhibition, Themselves Affect Hepatic Microcirculation, Liver Function, and Hepatocellular Integrity
Authors: SCHEINGRABER STEFAN , MESSNER SVEN , MATT SUSANNE , ABEL KATHRIN , GOGER SIMONE , KÖSTNER KIM , SCHILLING MARTIN K. , MENGER MICHAEL D.
Published: March 2009

Background:Metalloporphyrins (MPs) are broadly used in the studies of the role of the heme oxygenase (HO)‐1 system in different stress models. However, possible side effects of the MP administration itself have to be further investigated.Methods:Sin IV mesoporpyhrin IX (SnMP; 10 μmol/kg body weight), tin protoporpyhrin IX (SnPP; 50 μmol/kg body weight), or chromium mesoporpyhrin IX (CrMP; 40 μmol/kg body weight) were administered to Sprague‐Dawley rats (each group,n=5). The hepatic microcirculation was assessed by intravital microscopy (IVM). Blood samples were taken and the activity of HO‐1 inhibition was measured by the determination of bilirubin accumulation after bile duct ligation.Results:CrMP administration led to a decrease in mean arterial pressure. CrMP induced a marked hemolysis, a significant decrease of sinusoidal diameter and blood flow, and a marked inflammatory response. SnMP decreased sinusoidal diameters; however, this was compensated by an increase of sinusoidal red blood cell velocity. SnPP, but not SnMP, led to an increase of the number of nonperfused sinusoids. SnPP and CrMP revealed a two‐fold increase in aspartite aminotransferase values after the completion of the IVM. The administration of MPs led to a 40%–50% decrease in the levels of conjugated bilirubin therapy, indicating that they actually inhibit HO‐1 activity.Conclusions:The administration of MPs affects both the systemic macrohemodynamics and the hepatic microcirculation. As SnMP displayed the smallest number of side effects, this MP can be recommended for the studies of the HO‐1 action on the liver microcirculation.
Families, Not Parents, Differ: Development of Communication in Finnish Infants
Authors: Haapakoski Maija , Silvén Maarit
Published: March 2009

This longitudinal study on Finnish families was conducted to identify developmental differences in family‐level communication among mothers, fathers, and their infants during the second half of the infant's first year, and associations with infants' later language and communicative skills. We examined coregulated communication of parent‐infant dyads during 5‐min laboratory play sessions at 7 and 11 months. Few differences in mutually regulated communicative exchanges emerged between maternal and paternal dyads, and few developmental changes were found across the whole sample. Families with different communication profiles were identified, and changes rather than stability characterized communicative development at the family level. The family‐level differences at 7 months predicted variation in children's language and communicative skills at 14 months.
Polarized Growth in Budding Yeast in the Absence of a Localized Formin
Authors: Gao Lina , Bretscher Anthony
Published: March 2009

Polarity is achieved partly through the localized assembly of the cytoskeleton. During growth in budding yeast, the bud cortex and neck localized formins Bni1p and Bnr1p nucleate and assemble actin cables that extend along the bud-mother axis, providing tracks for secretory vesicle delivery. Localized formins are believed to determine the location and polarity of cables, hence growth. However, yeast expressing the nonlocalized actin nucleating/assembly formin homology (FH) 1-FH2 domains of Bnr1p or Bni1p as the sole formin grow well. Although cables are significantly disorganized, analysis of directed transport of secretory vesicles is still biased toward the bud, reflecting a bias in correctly oriented cables, thereby permitting polarized growth. Myosin II, localized at the bud neck, contributes to polarized growth as a mutant unable to interact with F-actin further compromises growth in cells with an unlocalized formin but not with a localized formin. Our results show that multiple mechanisms contribute to cable orientation and polarized growth, with localized formins and myosin II being two major contributors.
5 Proximity and Presence
Authors: Rotman Andy
Published: March 2009

Chapter 5 continues an analysis of prasāda, first focusing on the Toyikā story, which offers an egalitarian vision of the practice of prasāda in a time after the Buddha’s final nirvāṇa This account offers additional insight into the specifics of ritual action and the construction of shrines, and the importance of proximity and place for the mechanics of prasāda. This configuration of prasāda stresses a logic of presence, and the geography of practice that emerges may offer a subaltern perspective on early Buddhist pilgrimage.
7 Past and Present
Authors: Rotman Andy
Published: March 2009

Chapter 7 returns to the Koṭikarṇa-avadāna and considers what monastics say about seeing the Buddha and what they do when confronted with the opportunity. The chapter then focuses on two accounts from the Aśoka cycle of stories that address the problem of how to see the Buddha’s physical body after he has passed into final nirvāṇa. The first concerns King Aśoka and the logistics of pilgrimage, and the second involves Upagupta and the veneration of images.
Visualization of genomic data with the Hilbert curve
Authors: Anders Simon
Published: March 2009

In many genomic studies, one works with genome-position-dependent data, e.g. ChIP-chip or ChIP-Seq scores. Using conventional tools, it can be difficult to get a good feel for the data, especially the distribution of features. This article argues that the so-called Hilbert curve visualization can complement genome browsers and help to get further insights into the structure of one's data. This is demonstrated with examples from different use cases. An open-source application, called HilbertVis, is presented that allows the user to produce and interactively explore such plots.

Availability:  http://www.ebi.ac.uk/huber-srv/hilbert/

Contact:  sanders@fs.tum.de

Supplementary information:  Supplementary Data are available at Bioinformatics online.
Ecological consequences of Late Quaternary extinctions of megafauna
Authors: Johnson C.N.
Published: March 2009

Large herbivorous vertebrates have strong interactions with vegetation, affecting the structure, composition and dynamics of plant communities in many ways. Living large herbivores are a small remnant of the assemblages of giants that existed in most terrestrial ecosystems 50 000 years ago. The extinction of so many large herbivores may well have triggered large changes in plant communities. In several parts of the world, palaeoecological studies suggest that extinct megafauna once maintained vegetation openness, and in wooded landscapes created mosaics of different structural types of vegetation with high habitat and species diversity. Following megafaunal extinction, these habitats reverted to more dense and uniform formations. Megafaunal extinction also led to changes in fire regimes and increased fire frequency due to accumulation of uncropped plant material, but there is a great deal of variation in post-extinction changes in fire. Plant communities that once interacted with extinct large herbivores still contain many species with obsolete defences against browsing and non-functional adaptations for seed dispersal. Such plants may be in decline, and, as a result, many plant communities may be in various stages of a process of relaxation from megafauna-conditioned to megafauna-naive states. Understanding the past role of giant herbivores provides fundamental insight into the history, dynamics and conservation of contemporary plant communities.
Dynamics of crowing development in the domestic Japanese quail (Coturnix coturnix japonica)
Authors: Derégnaucourt Sébastien , Saar Sigal , Gahr Manfred
Published: March 2009

Species-specific behaviours gradually emerge, via incomplete patterns, to the final complete adult form. A classical example is birdsong, a learned behaviour ideally suited for studying the neural and molecular substrates of vocal learning. Young songbirds gradually transform primitive unstructured vocalizations (subsong, akin to human babbling) into complex, stereotyped sequences of syllables that constitute adult song. In comparison with birdsong, territorial and mating calls of vocal non-learner species are thought to exhibit little change during development. We revisited this issue using the crowing behaviour of domestic Japanese quail (Coturnix coturnix japonica). Crowing activity was continuously recorded in young males maintained in social isolation from the age of three weeks to four months. We observed developmental changes in crow structure, both the temporal and the spectral levels. Speed and trajectories of these developmental changes exhibited an unexpected high inter-individual variability. Mechanisms used by quails to transform sounds during ontogeny resemble those described in oscines during the sensorimotor phase of song learning. Studies on vocal non-learners could shed light on the specificity and evolution of vocal learning.
Assessment of cardiovascular regulation through irreversibility analysis of heart period variability: a 24 hours Holter study in healthy and chronic heart failure populations
Authors: Porta Alberto , D'addio Gianni , Bassani Tito , Maestri Roberto , Pinna Gian Domenico
Published: March 2009

We propose an approach based on time reversibility analysis to characterize the cardiovascular regulation and its nonlinearities as derived from 24 hours Holter recordings of heart period variability in a healthy population (
n
=12, age: median=43 years, range=34–55 years) and in a pathological group of age-matched chronic heart failure (CHF) patients (
n
=13, primarily in NYHA class II, age: median=37 years, range=33–56 years, ejection fraction: median=25%, range=13–30%). Two indices capable of detecting nonlinear irreversible dynamics according to different strategies of phase-space reconstruction (i.e. a fixed two-dimensional phase-space reconstruction and an optimal selection of the embedding dimension, respectively) are tested and compared with a more traditional nonlinear index based on local nonlinear prediction. Results showed that nonlinear dynamics owing to time irreversibility at short time scales are significantly present during daytime in healthy subjects, more frequently present in the CHF population and less frequently during night-time in both groups, thus suggesting their link with a dominant sympathetic regulation and/or with a vagal withdrawal. On the contrary, nonlinear dynamics owing to time irreversibility at longer, dominant time scales were insignificantly present in both groups. During daytime in the healthy population, irreversibility was mostly due to the presence of asymmetric patterns characterized by bradycardic runs shorter than tachycardic ones. Nonlinear dynamics produced by mechanisms different from those inducing temporal irreversibility were significantly detectable in both groups and more frequently during night-time. The present study proposes a method to distinguish different types of nonlinearities and assess their contribution over different temporal scales. Results confirm the usefulness of this method even when applied in uncontrolled experimental conditions such as those during 24 hours Holter recordings.
Modelling and disentangling physiological mechanisms: linear and nonlinear identification techniques for analysis of cardiovascular regulation
Authors: Batzel Jerry , Baselli Giuseppe , Mukkamala Ramakrishna , Chon Ki H
Published: March 2009

Cardiovascular (CV) regulation is the result of a number of very complex control interactions. As computational power increases and new methods for collecting experimental data emerge, the potential for exploring these interactions through modelling increases as does the potential for clinical application of such models. Understanding these interactions requires the application of a diverse set of modelling techniques. Several recent mathematical modelling techniques will be described in this review paper. Starting from Granger's causality, the problem of closed-loop identification is recalled. The main aspects of linear identification and of grey-box modelling tailored to CV regulation analysis are summarized as well as basic concepts and trends for nonlinear extensions. Sensitivity analysis is presented and discussed as a potent tool for model validation and refinement. The integration of methods and models is fostered for a further physiological comprehension and for the development of more potent and robust diagnostic tools.
Depression of cardiovascular autonomic function is more pronounced after mitral valve surgery: evidence for direct trauma
Authors: Retzlaff Beatrice , Bauernschmitt Robert , Malberg Hagen , Brockmann Gernot , Uhl Christian , Lange Rüdiger , Kurths Jürgen , Bretthauer Georg , Wessel Niels
Published: March 2009

The analysis of baroreflex sensitivity (BRS) and heart rate variability (HRV) leads to additional insights into patients' prognosis after cardiovascular events. The following study was performed to assess the differences in the post-operative recovery of autonomic regulation after mitral valve (MV) and aortic valve (AV) surgery with a heart–lung machine. Among the 43 consecutive male patients enrolled in a prospective study, 26 underwent isolated AV surgery and 17 isolated MV surgery. Blood pressure as well as ECG signals were recorded the day before, 24 hours after and one week after surgery. BRS was calculated according to the dual sequence method, and HRV was calculated using standard linear as well as nonlinear parameters. There were no major differences between the two groups in the pre-operative values. At 24 hours a comparable depression of HRV and BRS in both groups was observed, while at 7 days there was partial recovery in AV patients, which was absent in MV patients:
p
(AV versus MV)<0.001. While the response of the autonomic system to surgery is similar in AV and MV patients, there is obviously a decreased ability to recover in MV patients, probably attributed to traumatic lesions of the autonomic nervous system by opening the atria. Ongoing research is required for further clarification of the pathophysiology of this phenomenon and to establish strategies to restore autonomic function.
Positioning cytokinesis
Authors: Oliferenko Snezhana , Chew Ting Gang , Balasubramanian Mohan K.
Published: March 2009

Cytokinesis is the terminal step of the cell cycle during which a mother cell divides into daughter cells. Often, the machinery of cytokinesis is positioned in such a way that daughter cells are born roughly equal in size. However, in many specialized cell types or under certain environmental conditions, the cell division machinery is placed at nonmedial positions to produce daughter cells of different sizes and in many cases of different fates. Here we review the different mechanisms that position the division machinery in prokaryotic and eukaryotic cell types. We also describe cytokinesis-positioning mechanisms that are not adequately explained by studies in model organisms and model cell types.
Examining the relationship between typical drinking behavior and 21st birthday drinking behavior among college students: implications for event‐specific prevention
Authors: Lewis Melissa A. , Lindgren Kristen P. , Fossos Nicole , Neighbors Clayton , Oster‐Aaland Laura
Published: March 2009

Aims  The purpose of this research was to: (i) compare 21st birthday drinking with typical drinking; (ii) assess the prevalence of negative consequences and risk behaviors experienced during the 21st birthday week; and (iii) examine the role of typical drinking and 21st birthday drinking in explaining 21st birthday week negative consequences and risk behaviors.

Setting and participants  Participants (n = 306; 50% male) included college students turning 21 at a Midwestern public university in the United States.

Design and measurement  Approximately 1 week prior to their 21st birthday, students completed measures of typical past 3‐month alcohol consumption via a web‐based survey. Following their birthday, students (n = 296; 50% male) completed measures of 21st birthday week drinking as well as negative consequences and risk behaviors.

Findings  Findings indicated that students consumed considerably larger amounts of alcohol during the week of their 21st birthdays in comparison to typical weekly consumption. Additionally, students experienced a variety of negative consequences and risk behaviors during the week of their 21st birthday, including hangovers, vomiting and not remembering part of the previous evening. Negative binomial regression results indicated that those most likely to experience more negative consequences and risk behaviors associated with 21st birthday drinking were those who consumed heavy amounts of alcohol the week of their birthday, but who did not typically drink excessively.

Conclusions  Findings underscore the need to develop event‐specific prevention approaches for occasions associated with extreme drinking and provide direction for considering who may be at greatest risk for problems associated with celebratory drinking.
Retention in methadone maintenance drug treatment for prescription‐type opioid primary users compared to heroin users
Authors: Banta‐Green Caleb J. , Maynard Charles , Koepsell Thomas D. , Wells Elizabeth A. , Donovan Dennis M.
Published: March 2009

Aims  To assess retention in methadone maintenance treatment for prescription‐type opioid primary (PTOP) users compared to heroin users.

Design and participants  A retrospective cohort study was carried out to examine the association between opiate types used on 12‐month retention. The study population consisted of adults admitted to one of 11 not‐for‐profit methadone maintenance clinics in 2004 and 2005 throughout Washington State (n = 2308). Logistic regression analyses with fixed effects for treatment agencies were conducted.

Measurements  Opiate use type in past 30 days: any heroin use or primary prescription opioid without heroin use. Demographics, other drugs used, self‐reported medical and psychiatric concerns, social, familial and legal issues, public assistance type and housing stability were documented at intake using a comprehensive biopsychosocial instrument, the Treatment and Assessment Reports Generation Tool.

Findings  The odds of being retained in treatment for PTOP compared to heroin users not adjusting for other factors was 1.33 (95% confidence interval [CI], 1.03, 1.71). In the final logistic regression model the odds of retention for PTOP compared to heroin users was 1.25 (95% CI, 0.93, 1.67), indicating that there was no statistically significant difference in treatment retention by opiate type after adjusting for demographics, treatment agencies, other drug use, public assistance type, medical, psychiatric, social, legal and familial factors.

Conclusion  The findings of this study suggest that PTOP can be treated at methadone maintenance treatment facilities at least as effectively as heroin users in terms of treatment retention.
The Hewitt airway – the first known artificial oral ‘air‐way’ 101 years since its description
Authors: Haridas R. P.
Published: March 2009

The year 2008 marked 100 years since the publication of Sir Frederic W. Hewitt’s description of his artificial airway. Hewitt’s airway was the first known oral airway and laid the foundations for the numerous other airways that were later developed. Oral airways made anaesthesia safer and significantly reduced the trauma associated with earlier attempts at managing the obstructed airway.
Awake intubation using the LMA‐CTrach™ in patients with difficult airways*
Authors: López A. M. , Valero R. , Pons M. , Anglada T.
Published: March 2009

We studied 21 patients with known difficult airways who underwent awake tracheal intubation using the LMA CTrach™. Patients were given midazolam, atropine, a continuous infusion of remifentanil and topical lidocaine applied to the oropharyx. We limited the number of insertion attempts to three and the time to adjust the view to 5 min. In case of failure, we performed awake fibreoptic tracheal intubation. We found insertion of the device was successful and well tolerated in all patients. Vocal cords could be seen immediately in nine patients and following corrective manoeuvres in 10 patients. Tracheal intubation was successful in 20 patients: 19 cases under direct vision and in one blindly. In one patient with undiagnosed lingual tonsil hyperplasia, tracheal intubation was impossible using the device. No patient had an unpleasant recall of the procedure. We conclude that the LMA CTrach is easy to use, well tolerated and suitable for awake orotracheal intubation in patients with known difficult airways.
Patient information about general anaesthesia on the internet
Authors: Tallgren M. , Bäcklund M.
Published: March 2009

The internet is a frequently consulted source of health information. Using the Google search engine, we searched for patient information about general anaesthesia on the world wide web, using four synonyms of the term in four languages and analysing the top 20 results. Of the 320 search results, 104 (32%) contained relevant information: 36 (45%) with the English (UK); 39 (49%) with the English (US); 13 (16%) with the Swedish; and 16 (20%) with the Finnish search terms (p < 0.001). ‘Good’ websites, defined as those with a DISCERN rating of 4–5 stars, were found in all languages: 12 with the English (UK); 11 with the English (US); two with the Swedish; and one with the Finnish search terms (p = 0.012). Few good websites showed a reading grade level of ≤ 8 that is recommended for consumer health information. Of the good quality sites, 18/22 (82%) remained within the top 20, three months later.
Effects of reverse Trendelenburg position and inguinal compression on femoral vein cross‐sectional area in infants and young children
Authors: Suk E. H. , Kim D. H. , Kil H. K. , Kweon T. D.
Published: March 2009

This study evaluated the effects of the reverse Trendelenburg position and additional inguinal compression on the cross‐sectional area of the femoral vein in paediatric patients. Seventy subjects were allocated to two groups: the infants group and the children group. Cross‐sectional area of the femoral vein was measured just below the inguinal ligament using ultrasound. Three measurements were obtained for each patient: (i) supine, (ii) reverse Trendelenburg position and (iii) reverse Trendelenburg position with inguinal compression. In the infants group, femoral vein cross‐sectional area increased by a mean (SD) of 21.1 (15.2) % in the reverse Trendelenburg position and by 60.7 (30.8) % in the reverse Trendelenburg position with inguinal compression; whereas in the children group, femoral vein cross‐sectional area increased by 24.7 (15.8) % in the reverse Trendelenburg position and by 100.3 (50.7) % in the reverse Trendelenburg position with inguinal compression. Inguinal compression in the reverse Trendelenburg position offers a useful means of increasing femoral vein cross‐sectional area in paediatric patients.
Validation of a bedside activated clotting time test (Hemochron® Jr II Signature) with low dose heparin therapy
Authors: Racioppi L. , Quinart A. , Biais M. , Nouette‐Gaulain K. , Revel P. , Sztark F.
Published: March 2009

The purpose of this study was to validate a device designed to measure activated clotting time in low‐range heparin plasma concentrations (ACT‐LR) prospectively during the post‐operative period of vascular surgery. Measurement of ACT‐LR and activated partial thromboplastin time (APTT) were performed before heparinisation (T0) and at the end of surgery (T1). ACT‐LR(T1) and ΔACT‐LR (defined as ACT‐LR(T1) – ACT‐LR(T0)) were evaluated as diagnostic tests for excessive anticoagulation, defined by APTT more than twice the laboratory’s normal, by Bland‐Altman method and receiver operating characteristic (ROC) curves. In 103 patients, mean (SD) ACT‐LR was 137 (33) s at T0 and 176 (39) s at T1. Bland‐Altman graph did not show a good agreement between APTT and ACT‐LR. Areas under ROC curves were 0.82 (95% CI: 0.75–0.89) and 0.87 (95% CI: 0.80–0.93) for ACT‐LR(T1) and ΔACT‐LR, respectively. Using a threshold of 32 s for ΔACT‐LR, test sensitivity was 87% (95% CI: 81–93%), specificity was 85% (95% CI: 78–92%), positive predictive value was 90% (95% CI: 84–96%) and negative predictive value was 81% (95% CI: 73–86%). While ΔACT‐LR may have some potential in evaluating excessive anticoagulation in vascular surgery, the poor correlation between ACT‐LR and APTT does not support its routine use.
Widespread syn‐sedimentary deformation on a muddy deep‐water basin‐floor: the Vischkuil Formation (Permian), Karoo Basin, South Africa
Authors: Van Der Merwe W. C. , Hodgson D. M. , Flint S. S.
Published: March 2009

The ∼380‐m‐thick mudstone–siltstone‐dominated Vischkuil Formation represents the initiation phase of a 1.3‐km‐thick prograding basin floor to slope to shelf succession that marks a significant increase in the rate of siliciclastic sediment supply to the early Karoo Basin in the Permian. In the upper Vischkuil Formation three well exposed, widespread (∼3000 km2) 10–70‐m‐thick intervals of deformed strata are encased within undeformed sediments. Such chaotic mass movement deposits that are mappable over areas comparable with seismic‐scale mass transport deposits are commonly associated with submarine slope settings. However, the surrounding lithofacies and the correlation of distinctive marker beds indicate that these deformation intervals developed in a distal low gradient basin floor setting. The deformed intervals comprise a lower division of tight down‐flow verging folds dissected by thrust planes that sole out onto a highly sheared décollement surface that are interpreted as slides. The lower divisions are overlain by an upper division of chaotic lithofacies with large contorted clasts of sandstone supported by a fine‐grained matrix interpreted as a debrite. The juxtaposition of these lithofacies, the distribution of thickness of the divisions, and their close kinematic relationships indicate that the emplacement of the debris‐flows triggered and drove the underlying slide, in a low‐gradient distal setting. Individual beds in the deformed intervals can be mapped laterally into undeformed strata indicating limited movement of the slide. Therefore, widespread zones of syn‐sedimentary deformation in deep‐water settings do not necessarily indicate a slope setting and should not be used as single criterion to determine depositional setting. When associated with major debrites they may be developed on a flat basin floor.
Silymarin inhibited proliferation and induced apoptosis in hepatic cancer cells
Authors: Ramakrishnan G. , Lo Muzio L. , Elinos‐Báez C. M. , Jagan S. , Augustine T. A. , Kamaraj S. , Anandakumar P. , Devaki T.
Published: March 2009

Objectives:  The aim of this study was to investigate mechanisms involved in the growth inhibitory effect of silymarin, in humanhepatocellular carcinoma.

Materials and Methods:  The human hepatocellular carcinoma cell line HepG2 was utilized and the MTT assay was performed to study the antiproliferative effect of silymarin. Dual staining was undertaken for ethidium bromide/acridine orange, propidium iodide staining and DNA fragmentation studies were executed to confirm the presence of apoptosis. Cell‐cycle analysis was revealed by flow cytometry and mitochondrial transmembrane potential was measured by uptake of the mitochondrial‐specific lipophilic cationic dye rhodamine 123. Western blotting analysis for cytochrome c, p53, Bax, Bcl‐2, APAF‐1, caspase‐3, survivin, β‐catenin, cyclin D1, c‐Myc and PCNA was carried out.

Results:  Silymarin inhibited population growth of the hepatocellular carcinoma cells in a dose‐dependent manner, and the percentage of apoptotic cells was increased after treatment with 50 and 75 µg/ml silymarin for 24 h. Silymarin treatment increased the proportion of cells with reduced DNA content (sub‐G0/G1 or A0 peak), indicative of apoptosis with loss of cells in the G1 phase. Silymarin also decreased mitochondrial transmembrane potential of the cells, thereby increasing levels of cytosolic cytochrome c while up‐regulating expression of pro‐apoptotic proteins (such as p53, Bax, APAF‐1 and caspase‐3) with concomitant decrease in anti‐apoptotic proteins (Bcl‐2 and survivin) and proliferation‐associated proteins (β‐catenin, cyclin D1, c‐Myc and PCNA).

Conclusions:  Our results demonstrate that silymarin treatment inhibited proliferation and induced apoptosis in the human hepatocellular carcinoma cell line HepG2.
Widespread impairment of cell proliferation in the neonate Ts65Dn mouse, a model for Down syndrome
Authors: Contestabile A. , Fila T. , Cappellini A. , Bartesaghi R. , Ciani E.
Published: March 2009

Objectives: Among the many pathological aspects of Down syndrome, brain hypoplasia and mental retardation have been recently ascribed to defective proliferation of neural precursors during central nervous system development. By analogy, other features of Down syndrome, such as heart defects, gastrointestinal abnormalities, craniofacial dystrophy and reduced growth rate could be related, at least in theory, to similar proliferation impairment in peripheral tissues.

Materials and methods: In order to test this hypothesis, we evaluated cell proliferation in peripheral tissues of the Ts65Dn mouse, one of the animal models most commonly used to investigate Down syndrome.

Results: In fibroblast cultures from neonatal Ts65Dn mice, we found that cell proliferation was notably impaired. While length of the cell cycle was similar in fibroblasts from Ts65Dn and control mice, the number of actively proliferating cells was significantly smaller in Ts65Dn mice. Moreover, fibroblasts from Ts65Dn animals exhibited limited population‐doubling capacity, decreased proliferative lifespan and premature senescence. Analysis of cell proliferation in the skin of neonates, in vivo, showed that in Ts65Dn mice, cell proliferation was significantly reduced compared to control mice.

Conclusions: Our results suggest that defective proliferation may be a generalized feature of trisomic mice. In view of the genetic and phenotypic similarities between Ts65Dn mice and individuals with Down syndrome, proliferation impairment in various organs may also occur in subjects with Down syndrome. Thus, perturbation of a basic developmental function, cell proliferation, may be a critical determinant that contributes to the many aspects of pathology of this condition.
Preparation and sensory perception of fat‐free foams – effect of matrix properties and level of aeration
Authors: Minor Marcel , Vingerhoeds Monique H. , Zoet Franklin D. , De Wijk René , Van Aken George A.
Published: March 2009

The sensory perception of fat‐free model foams with a consistency between pourable (liquid; xanthan thickened) and spoonable (semi‐solid; gelled; carrageenan thickened) and varying level of aeration was studied. At low air contents (5, 10% v/v) perception is largely determined by the matrix properties; the presence of air is hardly experienced. On the other hand, at high levels of aeration (80% v/v) perception is determined by bubble characteristics and the matrix plays a negligible role in perception. Bubbles were better noticeable in a semi‐solid, i.e. carrageenan matrix, than in liquid, i.e. xanthan‐based foams. In semi‐solid sucrose–ester carrageenan foams, large bubbles were perceived as more airy and less creamy, compared with the same compositions with smaller bubbles.
Rheological properties of Josapine pineapple juice at different stages of maturity
Authors: Shamsudin Rosnah , Wan Daud Wan Ramli , Takrif Mohd Sobri , Hassan Osman , Ilicali Coskan
Published: March 2009

The rheological behaviour of Josapine pineapple juice with at various maturity stages was studied at a wide range of temperature (5–65 °C) and concentration (4–14 °Brix) using a rotational rheometer as the measuring system. The results show that josapine pineapples juice demonstrated a Newtonian behavior and is influenced by maturity stage, temperature and concentration. The Arrhenius typed equation successfully describe the effect of temperature on the viscosity, on the other hand, the effect of concentration can be described better using exponential equation. Finally, an equation describing the combined effect of temperature and concentration on viscosity at different stages of maturity was successfully developed.
Stability and rheological behaviour of salad dressing obtained with whey and different combinations of stabilizers
Authors: De Cássia da Fonseca Vânia , Haminiuk Charles Windson Isidoro , Izydoro Dayane Rosalyn , Waszczynskyj Nina , De Paula Scheer Agnes , Sierakowski Maria‐Rita
Published: March 2009

In this work the stability and the rheological behaviour of salad dressing containing ‘Minas Frescal’ whey cheese was studied. The salad dressing was stabilised by xanthan gum (XG), propylene glycol alginate (PGA) and carboxymethylcellulose (CMC). All samples were stable for a period of 4 months. The rheological model of Ostwald‐de‐Waelle (Power‐Law) was used in order to fit the data and to obtain the rheological parameters of flow behaviour index (n), consistency coefficient and apparent viscosity (ηap). All formulations showed a pseudoplastic behaviour and the PGA contributed to increase the values of flow behaviour index. Consistency coefficient was similarly affected by XG and PGA fractions. Apparent viscosity was highly influenced by the hydrocolloid CMC, with higher values of apparent viscosity in the proportion of 0.25/0.25/0.5% (PGA/XG/CMC). Hydrocolloid association (ternary mixtures) was statistically significant, resulting in an increase of K and ηap parameters. The results show that salad dressing with whey as aqueous phase and stabilised by a ternary combination of XG, PGA and CMC can be a technological alternative to the food industry.
Consumer evaluation of bakery product flavour as affected by incorporating the prebiotic tagatose
Authors: Armstrong Laura M. , Luecke Katherine J. , Bell Leonard N.
Published: March 2009

This study evaluated whether incorporating tagatose, a monosaccharide with prebiotic properties, into bakery products affected their flavours. Cinnamon muffins, lemon cookies, and chocolate cakes were prepared; 1 or 2% tagatose was added to the experimental products while an equal amount of sucrose was added to the control products. Using triangle tests, untrained consumer panels (n=65–81) were unable to distinguish between the flavour of products with and without tagatose. In addition, the flavours of bakery products containing and not containing tagatose were liked similarly. Based on this data, bakery products may be formulated containing low levels of tagatose for its health benefits without altering the product’s flavour.
Fast laboratory test results alone cannot deliver the benefits of near patient testing: a follow‐up study after 3 years of extended laboratory service at a primary health care centre
Authors: Haglund Sofie , Transö Bente , Persson Lars‐Göran , Zafirova Tamara , Grodzinsky Ewa
Published: March 2009

Objectives  Technological development has progressed towards point‐of‐care testing (POCT) at primary health care centres (PHCs). However, to our knowledge, there has been no extensive evaluation of the effects on patient and clinical logistics when an extended laboratory service (ELS) is offered.

Methods  Questionnaires were used to evaluate patient logistics before the introduction of ELS and after 6 months, as the proportion of consultations completed within one visit. That is, the patient is sampled, the test result is made available, and the patient is informed of the clinical decision. After 3 years of ELS, clinical logistics were followed up using questionnaires and by measuring turnaround time (TAT) from sampling to available test result (TATa) and from sampling to a clinical decision (TATd), and the proportion of laboratory test results reported back to the patient on the day of sampling (TATi).

Results  After 6 months of ELS, the theoretical proportion of consultations which could be completed within 1 day had increased from 20% to 68%, while the proportion of patients desiring this situation had increased from 72% to 85%. After 3 years of ELS, the TATi was 56%. However, the majority of these tests were from the menu available before ELS. While 66% of patients wished to receive the laboratory test results at the consultation, this was achieved in 42% of cases. Patients below 65 years of age were more anxious than older patients to complete the consultation within a single PHC visit.

Conclusions  The clinical logistics concerning TATi did not correspond to the patients' wishes. When the consultation was completed within 1 day, the majority of the laboratory analyses were from the menu available before ELS. An ELS alone cannot deliver all the desired benefits of POCT.
The subjective incremental cost of informed consent and documentation in hospital care: a multicentre questionnaire survey in Japan
Authors: Fukuda Haruhisa , Imanaka Yuichi , Kobuse Hiroe , Hayashida Kenshi , Murakami Genki
Published: March 2009

Objective  To reveal the amount of time and financial cost required to obtain informed consent and to preserve documentation.

Methods  The questionnaire was delivered to all staff in six acute care public hospitals in Japan. We examined health care staff perceptions of the time they spent obtaining informed consent and documenting information. All data were collected in 2006 and estimates in the past week in 2006 were compared to estimates of time spent in a week in 1999. We also calculated the economic costs of incremental amounts of time spent in these procedures.

Results  In 2006, health care staff took about 3.89 hours [95% Confidence Interval (CI) 3.71–4.07] per week to obtain informed consent and 6.64 hours (95% CI 6.40–6.88) per week to write documentation on average. Between 1999 and 2006, the average amount of time for conducting informed consent was increased to 0.67 (P < 0.001) hours per person‐week, and the average amount of time for documentation was increased to 0.70 (P < 0.001) hours per person‐week. The annual economic cost of activities for informed consent and documentation in a 100‐bed hospital increased from 117 755 to 449 402 US dollars.

Conclusions  We found a considerable increase in time spent on informed consent and documentation, and associated cost over a 7‐year time period. Although greater attention to the informed consent process should be paid to ensure the notions of patient autonomy and self‐determination, the increased resources devoted to these practices must be considered in light of current cost containment policies.
Preliminary reliability of an observer rating scale for assessing medication adherence on psychiatric wards
Authors: Byrne Mitchell K. , Deane Frank P. , Willis Aimee , Hawkins Barbara , Quinn Rebecca
Published: March 2009

Objectives  Medication non‐adherence is a major contributor to poor outcomes following discharge from psychiatric hospitals. It is therefore imperative that staff are able to accurately assess the extent to which patients have engaged with treatment. This study presents data on a new observer rating instrument of patient medication adherence.

Methods  Staff participating in a medication adherence training programme (‘Medication Alliance’) were given a brief overview of the Observer Rating of Medication Taking (ORMT) scale. Participants then watched six video vignettes of patient adherence behaviour and provided a rating on their scale for each vignette. Participant ratings were then compared with ‘expert’ ratings.

Results  Percentage agreement between ‘experts’ and participants ranged from a low of 68% through to 98% agreement. Only one vignette was rated significantly differently [Mdiff = 0.33, t(49) = 2.08, P = 0.007], with 32% of people falling outside the expert rating range (all of those ratings being higher). This difference was attributed to between group differences, [F(2,47) = 3.49, P < 0.05] and post hoc assessment suggested that the differences between expert and trainee ratings for the vignette may be explained by trainee characteristics, as distinct from inherent characteristics of the rating scale.

Conclusion  The ORMT can help mental health professionals identify particular non‐adherent behaviours thus facilitating identification and treatment of likely non‐adherence before discharge. The scale appears to be accessible to a variety of professions with a range of experience and requires minimum training in order to be used reliably.