bluuebunny/crossref_metadata_2025 huggingface dataset:
Small-molecule tools for dissecting the roles of SSB/protein interactions in genome maintenance
Authors: Lu Duo , Bernstein Douglas A. , Satyshur Kenneth A. , Keck James L.
Published: December 2009

Bacterial single-stranded DNA-binding proteins (SSBs) help to recruit a diverse array of genome maintenance enzymes to their sites of action through direct protein interactions. For all cases examined to date, these interactions are mediated by the evolutionarily conserved C terminus of SSB (SSB-Ct). The essential nature of SSB protein interactions makes inhibitors that block SSB complex formation valuable biochemical tools and attractive potential antibacterial agents. Here, we identify four small molecules that disrupt complexes formed between
Escherichia coli
SSB and Exonuclease I (ExoI), a well-studied SSB-interacting enzyme. Each compound disrupts ExoI/SSB-Ct peptide complexes and abrogates SSB stimulation of ExoI nuclease activity. Structural and biochemical studies support a model for three of the compounds in which they compete with SSB for binding to ExoI. The fourth appears to rely on an allosteric mechanism to disrupt ExoI/SSB complexes. Subsets of the inhibitors block SSB-Ct complex formation with two other SSB-interaction partners as well, which highlights their utility as reagents for investigating the roles of SSB/protein interactions in diverse DNA replication, recombination, and repair reactions.
Live-Cell Imaging in Caenorhabditis elegans Reveals the Distinct Roles of Dynamin Self-Assembly and Guanosine Triphosphate Hydrolysis in the Removal of Apoptotic Cells
Authors: He Bin , Yu Xiaomeng , Margolis Moran , Liu Xianghua , Leng Xiaohong , Etzion Yael , Zheng Fei , Lu Nan , Quiocho Florante A. , Danino Dganit , Zhou Zheng
Published: December 2009

Dynamins are large GTPases that oligomerize along membranes. Dynamin's membrane fission activity is believed to underlie many of its physiological functions in membrane trafficking. Previously, we reported that DYN-1 ( Caenorhabditis elegans dynamin) drove the engulfment and degradation of apoptotic cells through promoting the recruitment and fusion of intracellular vesicles to phagocytic cups and phagosomes, an activity distinct from dynamin's well-known membrane fission activity. Here, we have detected the oligomerization of DYN-1 in living C. elegans embryos and identified DYN-1 mutations that abolish DYN-1's oligomerization or GTPase activities. Specifically, abolishing self-assembly destroys DYN-1's association with the surfaces of extending pseudopods and maturing phagosomes, whereas inactivating guanosine triphosphate (GTP) binding blocks the dissociation of DYN-1 from these membranes. Abolishing the self-assembly or GTPase activities of DYN-1 leads to common as well as differential phagosomal maturation defects. Whereas both types of mutations cause delays in the transient enrichment of the RAB-5 GTPase to phagosomal surfaces, only the self-assembly mutation but not GTP binding mutation causes failure in recruiting the RAB-7 GTPase to phagosomal surfaces. We propose that during cell corpse removal, dynamin's self-assembly and GTP hydrolysis activities establish a precise dynamic control of DYN-1's transient association to its target membranes and that this control mechanism underlies the dynamic recruitment of downstream effectors to target membranes.
Penser la littérature médiévale: par-dela le binarisme
Authors: Cerquiglini-Toulet Jacqueline
Published: December 2009

Au-delà des formules binaires et du goût pour une pensée duelle qui caractérisent la pensée féodale selon Erich Auerbach, l'article analyse les figures de la complexité qu'offre le Moyen Âge. L'accent porté de plus en plus au fil du temps sur les états intermédiaires:
dorveille
,
nonchaloir
, clair-obscur signe la mise en question des vérités tranchées. Le blanc ne s'oppose plus au noir et des formules comme
Armes et Amours
s'adjoignent un troisième terme qui renvoie souvent à la littérature ou à la réflexivité. C'est l'ensemble de ces phénomènes que cerne l'article avec comme interrogation essentielle: comment écrit-on et lit-on la complexité dans les textes médiévaux, comment construit-on ou déconstruit-on du sens?
Propofol Depresses Angiotensin II–induced Cell Proliferation in Rat Cardiac Fibroblasts
Authors: Cheng Tzu-Hurng , Leung Yuk-Man , Cheung Chi-Wai , Chen Cheng-Hsien , Chen Yen-Ling , Wong Kar-Lok
Published: December 2009

Background

Propofol may have beneficial effects on the prevention of angiotensin II (Ang II)-induced cardiac fibroblast proliferation via its antioxidative properties. The authors hypothesized that propofol may alter Ang II-induced cell proliferation and aimed to identify the putative underlying signaling pathways in rat cardiac fibroblasts.

Methods

Cultured rat cardiac fibroblasts were pretreated with propofol then stimulated with Ang II; cell proliferation and endothelin-1 gene expression were examined. The effect of propofol on Ang II-induced nicotinamide adenine dinucleotide phosphate-oxidase activity, reactive oxygen species formation, extracellular signal-regulated kinase phosphorylation, and activator protein 1-mediated reporter activity were also examined. The effect of propofol on nitric oxide production and protein kinase B and endothelial nitric oxide synthase phosphorylations were also tested to elucidate the intracellular mechanism of propofol in proliferation.

Results

Ang II (100 nm) increased cell proliferation and endothelin-1 expression, which were partially inhibited by propofol (10 or 30 microm). Propofol also inhibited Ang II-increased nicotinamide adenine dinucleotide phosphate-oxidase activity, reactive oxygen species formation, extracellular signal-regulated kinase phosphorylation, and activator protein 1-mediated reporter activity. Propofol was also found to increase nitric oxide generation and protein kinase B and nitric oxide synthase phosphorylations. Nitric oxide synthase inhibitor (N-nitro-L-arginine methylester) and the short interfering RNA transfection for protein kinase B or endothelial nitric oxide synthase markedly attenuated the inhibitory effect of propofol on Ang II-induced cell proliferation.

Conclusions

The authors' results suggest that propofol prevents cardiac fibroblast proliferation by interfering with the generation of reactive oxygen species and involves the activation of the protein kinase B-endothelial nitric oxide synthase-nitric oxide pathway.
Effects of Dexmedetomidine and Propofol on Lower Esophageal Sphincter and Gastroesophageal Pressure Gradient in Healthy Volunteers
Authors: Turan Alparslan , Wo John , Kasuya Yusuke , Govinda Raghavendra , Akça Ozan , Dalton Jarrod E. , Sessler Daniel I. , Rauch Stefan
Published: December 2009

Background

Many anesthetics reduce lower esophageal sphincter pressure (LESP). Reduced pressure and consequent reduction in the gastroesophageal pressure gradient (GEPG) thus promotes gastroesophageal reflux and may contribute to aspiration pneumonia and associated morbidity. Therefore, the authors compared LESP and GEPG during dexmedetomidine and propofol sedation.

Methods

Using a randomized, double-blind, crossover design, 11 healthy volunteers were sedated on 2 separate days. Baseline LESP and GEPG were recorded each day. Subsequently, on each day volunteers received three 40-min-long sedative infusions of increasing doses of 0.6, 1.2, and 2.4 ng/ml dexmedetomidine or 1, 2, and 4 microg/ml propofol. LESP and GEPG were recorded during inhalation and expiration at 20 and 40 min after starting each infusion phase, and these measurements were averaged. Results are presented as mean (95% confidence interval).

Results

Two subjects did not return for the dexmedetomidine study day, and the dexmedetomidine results were unusable in another; propofol results in these volunteers were nonetheless retained for analysis. There were no significant differences in LESP and GEPG as a function of drug. However, there was a small but significant 7.4 (-1.6 to -13.2) mmHg (approximately 25%) dose-dependent decrease in LESP over the range of targeted low to high blood levels of each drug.

Conclusions

Both dexmedetomidine and propofol have similar effects on LESP and GEPG. Although both of the drugs cause some decrease in LESP at high concentrations, it is unlikely that this effect would promote gastroesophageal reflux during sedation.
Bupivacaine Inhibits Glutamatergic Transmission in Spinal Dorsal Horn Neurons
Authors: Furutani Kenta , Ikoma Miho , Ishii Hideaki , Baba Hiroshi , Kohno Tatsuro
Published: December 2009

Background

The local anesthetic bupivacaine is thought not only to block sodium channels but also to interact with various receptors. Here, the authors focus on excitatory glutamatergic transmission in the superficial dorsal horn of the spinal cord with respect to its importance for nociceptive processing.

Methods

The effects of bupivacaine on the response to exogenous administration of N-methyl-D-aspartate (NMDA) receptor agonists were examined in lamina II neurons of adult rat spinal cord slices using the whole-cell patch-clamp technique.

Results

Bupivacaine (0.5, 2 mm) dose-dependently reduced the peak amplitudes of exogenous NMDA-induced currents. However, this inhibitory effect of bupivacaine (2 mm) was not blocked by the presence of tetrodotoxin, a sodium channel blocker, or La(3+), a voltage-gated Ca+ channel blocker, and was unaffected by changes in pH conditions. Moreover, intrapipette guanosine-5'-O-(2-thiodiphosphate) (1 mm), a G-protein inhibitor, did not block the reduction of NMDA current amplitudes by bupivacaine. Similarly, lidocaine, ropivacaine, and mepivacaine also reduced the amplitudes of NMDA-induced currents.

Conclusions

These findings raise the possibility that the antinociceptive effect of bupivacaine may be due to direct modulation of NMDA receptors in the superficial dorsal horn. In addition to voltage-gated sodium channels, glutamate NMDA receptors are also important for analgesia induced by local anesthetics.
Guarding Pain and Spontaneous Activity of Nociceptors after Skin versus Skin Plus Deep Tissue Incision
Authors: Xu Jun , Brennan Timothy J.
Published: December 2009

Background

Guarding pain after rat plantar incision is similar to pain at rest in postoperative patients. Spontaneous activity (SA) in nociceptive pathways quite likely transmits such ongoing pain. This study examined the extent of tissue injury by incision on pain behaviors and nociceptor SA.

Methods

Rat pain behaviors were measured after a sham procedure, skin incision, or skin plus deep tissue incision. Separate groups of rats underwent in vivo single-fiber recording 1 day after a sham procedure, skin, or skin plus deep tissue incision or 7 days after skin plus deep tissue incision.

Results

Compared with the control procedure, skin incision induced moderate guarding on the day of incision only, whereas skin plus deep tissue incision caused guarding for 5 days. Mechanical and heat hyperalgesia were similar in both incised groups, except that mechanical hyperalgesia lasted longer after skin plus deep tissue incision. On Postoperative Day 1, skin incision (18.2%) produced a similar prevalence of SA in nociceptors as in controls (13.0%), whereas skin plus deep tissue incision generated a greater prevalence of SA (61.0%); SA rate also tended to be greater (6.1 vs. 10.0 imp/s) after skin plus deep tissue incision. Seven days after skin plus deep tissue incision, the SA prevalence was similar (13.6%) as in controls.

Conclusions

These data demonstrated that incised deep tissue rather than skin had a central role in the genesis of guarding behavior and nociceptor SA. Understanding the responses of deep tissue to incision and the mechanisms for deep tissue pain will improve postoperative pain management.
No Association between Intraoperative Hypothermia or Supplemental Protective Drug and Neurologic Outcomes in Patients Undergoing Temporary Clipping during Cerebral Aneurysm Surgery
Authors: Hindman Bradley J. , Bayman Emine O. , Pfisterer Wolfgang K. , Torner James C. , Todd Michael M.
Published: December 2009

Background

Although hypothermia and barbiturates improve neurologic outcomes in animal temporary focal ischemia models, the clinical efficacy of these interventions during temporary occlusion of the cerebral vasculature during intracranial aneurysm surgery (temporary clipping) is not established.

Methods

A post hoc analysis of patients from the Intraoperative Hypothermia for Aneurysm Surgery Trial who underwent temporary clipping was performed. Univariate and multivariate logistic regression methods were used to test for associations between hypothermia, supplemental protective drug, and short- (24-h) and long-term (3-month) neurologic outcomes. An odds ratio more than 1 denotes better outcome.

Results

Patients undergoing temporary clipping (n = 441) were assigned to intraoperative hypothermia (33.3 degrees +/- 0.8 degrees C, n = 208) or normothermia (36.7 degrees +/- 0.5 degrees C, n = 233), with 178 patients also receiving supplemental protective drug (thiopental or etomidate) during temporary clipping. Three months after surgery, 278 patients (63%) had good outcome (Glasgow Outcome Score = 1). Neither hypothermia (P = 0.847; odds ratio = 1.043, 95% CI = 0.678-1.606) nor supplemental protective drug (P = 0.835; odds ratio = 1.048, 95% CI = 0.674-1.631) were associated with 3-month Glasgow Outcome Score. The effect of supplemental protective drug did not significantly vary with temperature. The effects of hypothermia and protective drug did not significantly vary with temporary clip duration. Similar findings were made for 24-h neurologic status and 3-month Neuropsychological Composite Score.

Conclusion

In the Intraoperative Hypothermia for Aneurysm Surgery Trial, neither systemic hypothermia nor supplemental protective drug affected short- or long-term neurologic outcomes of patients undergoing temporary clipping.
Predicting Success on the Certification Examinations of the American Board of Anesthesiology
Authors: McClintock Joseph C. , Gravlee Glenn P.
Published: December 2009

Background

Currently, residency programs lack objective predictors for passing the sequenced American Board of Anesthesiology (ABA) certification examinations on the first attempt. Our hypothesis was that performance on the ABA/American Society of Anesthesiologists In-Training Examination (ITE) and other variables can predict combined success on the ABA Part 1 and Part 2 examinations.

Method

The authors studied 2,458 subjects who took the ITE immediately after completing the first year of clinical anesthesia training and took the ABA Part 1 examination for primary certification immediately after completing residency training 2 yr later. ITE scores and other variables were used to predict which residents would complete the certification process (passing the ABA Part 1 and Part 2 examinations) in the shortest possible time after graduation.

Results

ITE scores alone accounted for most of the explained variation in the desired outcome of certification in the shortest possible time. In addition, almost half of the observed variation and most of the explained variance in ABA Part 1 scores was accounted for by ITE scores. A combined model using ITE scores, residency program accreditation cycle length, country of medical school, and gender best predicted which residents would complete the certification examinations in the shortest possible time.

Conclusions

The principal implication of this study is that higher ABA/ American Society of Anesthesiologists ITE scores taken at the end of the first clinical anesthesia year serve as a significant and moderately strong predictor of high performance on the ABA Part 1 (written) examination, and a significant predictor of success in completing both the Part 1 and Part 2 examinations within the calendar year after the year of graduation from residency. Future studies may identify other predictors, and it would be helpful to identify factors that predict clinical performance as well.
Defining DIOS and Constipation in Cystic Fibrosis With a Multicentre Study on the Incidence, Characteristics, and Treatment of DIOS
Authors: Houwen Roderick H , van der Doef Hubert P , Sermet Isabelle , Munck Anne , Hauser Bruno , Walkowiak Jaroslaw , Robberecht Eddy , Colombo Carla , Sinaasappel Maarten , Wilschanski Michael ,   ESPGHAN Cystic Fibrosis Working Group
Published: December 2009

Objectives:

Various definitions for distal intestinal obstruction syndrome (DIOS), meconium ileus equivalent, and constipation in patients with cystic fibrosis (CF) are used. However, an unequivocal definition for DIOS, meconium ileus equivalent, and constipation is preferred. The aims of this study were, therefore, to seek consensus on the definitions for DIOS and constipation in patients with CF and to determine the incidence, characteristics, and treatment of DIOS in a cohort of paediatric patients with CF.

Methods:

During the 2005 European Society for Paediatric Gastroenterology, Hepatology, and Nutrition meeting in Porto a group of paediatric gastroenterologists discussed the definition of DIOS and constipation in CF. Subsequently, all patients younger than or equal to 18 years with complete DIOS according to the definition agreed upon and diagnosed during the years 2001 to 2005 in 8 CF centres were studied.

Results:

Distal intestinal obstruction syndrome was defined as an acute complete or incomplete faecal obstruction in the ileocaecum, whereas constipation was defined as gradual faecal impaction of the total colon. Fifty‐one episodes of DIOS in 39 patients were recorded, giving an overall incidence of 6.2 (95% confidence interval, 4.4–7.9) episodes per 1000 patient‐years. Of the 39 patients with DIOS, 20% experienced a relapse, 92% were pancreatic insufficient, 44% had a history of meconium ileus at birth, and 82% had a severe genotype. Conservative treatment was effective in 49 of 51 DIOS episodes (96%).

Conclusions:

The European Society for Paediatric Gastroenterology, Hepatology, and Nutrition CF Working Group definitions of DIOS and constipation in CF are specific and make a clear distinction between these 2 entities. The incidence of DIOS in the present study was considerably higher than reported previously.
Conceptualization and Treatment of Chronic Abdominal Pain in Pediatric Gastroenterology Practice
Authors: Schurman Jennifer V , Hunter Heather L , Friesen Craig A
Published: December 2009

Objectives:

The aim of this study was to examine how children with abdominal pain presently are viewed, assessed, and treated by pediatric gastroenterologists across North America, as well as how perspectives have changed since initial release of the Rome criteria for functional gastrointestinal disorders approximately 15 years ago.

Patients and Methods:

One hundred seventy‐four full members of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition completed a pediatric gastroenterology practice survey designed by the authors in 2006. The responses were examined for practice patterns and specific knowledge/use of the Rome criteria. The responses were also compared with historical data from 151 North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition members who completed a similar survey in 1992.

Results:

There were few changes in the evaluation, treatment, or outcomes for children with abdominal pain for the past 15 years. Knowledge of the Rome criteria was common, but use in practice was not; several specific problems with the criteria were identified. A mismatch also appeared between belief in the importance of psychological factors in the creation/maintenance of pediatric abdominal pain and integration of these factors as part of standard evaluation and treatment. Finally, controversy emerged regarding both the term “functional” and the importance of histologic inflammation in the pathophysiology of pediatric abdominal pain.

Conclusions:

The evolution and dissemination of the Rome criteria for the past 15 years have not substantially changed evaluation or treatment practices for children with abdominal pain. Many areas of inconsistency and controversy remain. More focused research is needed to better understand this common pain condition and to establish an effective treatment program that can be disseminated across practitioners.
Variable Clinical Spectrum of the Most Common Inborn Error of Bile Acid Metabolism—3β‐hydroxy‐Δ5‐C27‐steroid Dehydrogenase Deficiency
Authors: Subramaniam Pushpa , Clayton Peter T , Portmann Bernard C , Mieli‐Vergani Giorgina , Hadžić Nedim
Published: December 2009

Objective:

We studied the clinical features of children with 3β‐hydroxy‐Δ5‐C27‐steroid dehydrogenase (3β‐HSDH) deficiency presenting to King's College and Great Ormond Street hospitals between 1989 and 2005. The diagnosis was made biochemically by detection of sulphated dihydroxycholenoic acids and trihydroxycholenoic acids in urine by fast atom bombardment mass spectrometry or electrospray ionisation tandem mass spectrophotometry and a plasma bile acid profile showing absent or low cholic and chenodeoxycholic acid levels and high concentrations of 3β‐7α‐dihydroxy‐5‐cholenoic acid and 3β‐7α‐12α‐trihydroxy‐5‐cholenoic acid.

Results:

Eighteen children (12 male) with 3β‐HSDH deficiency were identified and diagnosed at a median age of 1.35 years (range 8 weeks–11 years). The presenting features included neonatal cholestasis (n = 11), rickets (n = 8, 1 of whom also had hypocalcaemic tetany, seizures, and normal liver biochemical markers), hepatomegaly (n = 7), pruritus (n = 3), and steatorrhoea and failure to thrive (n = 3). Ten children had low serum 25‐OH vitamin D levels, of whom 8 also had low vitamin E and 6 had low vitamin A serum levels. Liver histology showed giant cell change and hepatocyte disarray in all with added features of cholestasis in 11, bridging fibrosis in 6, micronodular cirrhosis in 1, fatty change in 1, and active lobular and portal inflammation in 1. Five patients were treated with cholic acid and chenodeoxycholic acid (7 mg · kg−1 · day−1 of each), 7 with chenodeoxycholic acid only (7–18 mg · kg−1 · day−1), and 1 with cholic acid (8 mg · kg−1 · day−1) only. Repeated liver biopsies performed in 4 patients 6 months after starting replacement therapy showed improved histological changes. Three children died untreated before 5 years of age. After a median follow‐up of 5.5 years (range 1–17 years) 12 out of 13 treated children have no clinical signs of liver disease or of fat‐soluble vitamin deficiency.

Conclusions:

3β‐HSDH deficiency is a rare inborn error of metabolism with diverse clinical features. Early replacement treatment leads to clinical and biochemical control and prevents chronic liver and bone disease, at least in the medium term.
Brain activity in an awake chimpanzee in response to the sound of her own name
Authors: Ueno Ari , Hirata Satoshi , Fuwa Kohki , Sugama Keiko , Kusunoki Kiyo , Matsuda Goh , Fukushima Hirokata , Hiraki Kazuo , Tomonaga Masaki , Hasegawa Toshikazu
Published: December 2009

The brain activity of a fully awake chimpanzee being presented with her name was investigated. Event-related potentials (ERPs) were measured for each of the following auditory stimuli: the vocal sound of the subject's own name (SON), the vocal sound of a familiar name of another group member, the vocal sound of an unfamiliar name and a non-vocal sound. Some differences in ERP waveforms were detected between kinds of stimuli at latencies at which P3 and Nc components are typically observed in humans. Following stimulus onset, an Nc-like negative shift at approximately 500 ms latency was observed, particularly in response to SON. Such specific ERP patterns suggest that the chimpanzee processes her name differently from other sounds.
Evolution of ultraviolet vision in shorebirds (Charadriiformes)
Authors: Ödeen Anders , Håstad Olle , Alström Per
Published: December 2009

Diurnal birds belong to one of two classes of colour vision. These are distinguished by the maximum absorbance wavelengths of the SWS1 visual pigment sensitive to violet (VS) and ultraviolet (UVS). Shifts between the classes have been rare events during avian evolution. Gulls (Laridae) are the only shorebirds (Charadriiformes) previously reported to have the UVS type of opsin, but too few species have been sampled to infer that gulls are unique among shorebirds or that Laridae is monomorphic for this trait. We have sequenced the SWS1 opsin gene in a broader sample of species. We confirm that cysteine in the key amino acid position 90, characteristic of the UVS class, has been conserved throughout gull evolution but also that the terns
Anous minutus, A. tenuirostris
and
Gygis alba
, and the skimmer
Rynchops niger
carry this trait. Terns, excluding
Anous
and
Gygis
, share the VS conferring serine in position 90 with other shorebirds but it is translated from a codon more similar to that found in UVS shorebirds. The most parsimonious interpretation of these findings, based on a molecular gene tree, is a single VS to UVS shift and a subsequent reversal in one lineage.
A speculum of chymical practice: Isaac Newton, Martin Lister (1639–1712), and the making of telescopic mirrors
Authors: Roos Anna Marie
Published: December 2009

In 1674 the natural philosopher and physician Martin Lister published a new method of making glass of antimony for telescopic mirrors, using Derbyshire cawk or barite as a flux. New manuscript evidence reveals that Sir Isaac Newton requested samples of the cawk and antimony from Lister through an intermediary named Nathaniel Johnston. An analysis of Lister's paper and Johnston's correspondence and its context reveals insights not only about Newton's work with telescopic specula but also about his alchemical investigations. Analysing these sources also contributes to our understanding of the nature of correspondence networks in the early ‘scientific revolution’ in England.
Qualitative criterion for interception in a pursuit/evasion game
Authors: Morgan J. A.
Published: December 2009

A qualitative account is given of a differential pursuit/evasion game. A criterion for the existence of an intercept solution is obtained using future cones that contain all attainable trajectories of target or interceptor originating from an initial position. A sufficient and necessary conditon that an opportunity to intercept always exists is that, after some initial time, the future cone of the target be contained within the future cone of the interceptor. The sufficient condition may be regarded as a kind of Nash equilibrium.
Studies of the Kinetic Mechanism of Maize Endosperm ADP-Glucose Pyrophosphorylase Uncovered Complex Regulatory Properties
Authors: Boehlein Susan K. , Shaw Janine R. , Stewart Jon D. , Hannah L. Curtis
Published: December 2009

ADP-glucose pyrophosphorylase catalyzes the synthesis of ADP-glucose (ADP-Glc) from Glc-1-phosphate (G-1-P) and ATP. Kinetic studies were performed to define the nature of the reaction, both in the presence and absence of allosteric effector molecules. When 3-phosphoglycerate (3-PGA), the putative physiological activator, was present at a saturating level, initial velocity studies were consistent with a Theorell-Chance BiBi mechanism and product inhibition data supported sequential binding of ATP and G-1-P, followed by ordered release of pyrophosphate and ADP-Glc. A sequential mechanism was also followed when 3-PGA was absent, but product inhibition patterns changed dramatically. In the presence of 3-PGA, ADP-Glc is a competitive inhibitor with respect to ATP. In the absence of 3-PGA—with or without 5.0 mm inorganic phosphate—ADP-Glc actually stimulated catalytic activity, acting as a feedback product activator. By contrast, the other product, pyrophosphate, is a potent inhibitor in the absence of 3-PGA. In the presence of subsaturating levels of allosteric effectors, G-1-P serves not only as a substrate but also as an activator. Finally, in the absence of 3-PGA, inorganic phosphate, a classic inhibitor or antiactivator of the enzyme, stimulates enzyme activity at low substrate by lowering the K  M values for both substrates.
What is associated with low food intake in older people with dementia?
Authors: Lin Li‐Chan , Watson Roger , Wu Shiao‐Chi
Published: December 2009

Aims.  The aim of this study was to investigate the risk factors of institutionalised older people for developing low food intake.

Background.  Eating difficulties among patients with dementia have been identified in western society and typically progress as dementia advances. Findings from previous studies reflect that low food intake or weight loss might not be a consequence of people with dementia being unable or unwilling to eat independently.

Design.  The study consisted of observers’ training and mealtime observations. Each data collector received two days of didactic and clinical training. Observation was done for two days during lunch and dinner.

Methods.  Four hundred seventy‐seven participants were selected from residents with dementia at nine dementia special care units in licensed long‐term care facilities in northern and central Taiwan. Data were collected using the Barthel index, Mini‐Mental State Examination (MMSE), and the Edinburgh Feeding Evaluation in Dementia (EdFED) scale.

Results.  The prevalence of low food intake at meals in residents with dementia in LTCF’s was 30·7%. Eating difficulty, no feeding assistance, moderate dependence, fewer family visits, being female and older, were six independent factors associated with low food intake after controlling for all other factors.

Conclusion.  Nursing staff need to assess residents’ feeding ability to continue to self‐feed. Also, to supervise the feeding of residents with moderate dependency and provide appropriate verbal or physical assistance at meal times is recommended.

Relevance to clinical practice.  Constructing strategies to encourage families to visit their older relatives in institutions is recommended.
Relationships between nurse care‐giving behaviours and preterm infant responses during bathing: a preliminary study
Authors: Liaw Jen‐Jiuan , Yang Luke , Chou Hsiu‐Ling , Yang Meei‐Horng , Chao Shih‐Ching
Published: December 2009

Aims. The purpose of this study was to explore the relationships between specific nurse care‐giving behaviours and preterm infant behavioural responses during bathing and to identify nurse behaviours associated with infant ‘stress’.

Background. Although recent advances in medical technology have improved neonatal intensive care, the high mortality and morbidity rates in preterm infants have not decreased proportionally. As caregivers strive to reduce infant mortality and morbidity, a factor for consideration is which caregiver behaviours are associated with preterm infant well‐being.

Design. A descriptive correlational design.

Method. Convenience samples of 24 preterm infants and 12 nurses were recruited. A total of 120 baths were videotaped. Infant and nurse behaviours were measured using the coding schemes developed by the researchers. Pearson coefficient correlation, non‐parametric Kruskal–Wallis test,t‐test and generalised linear models were methods for data analysis.

Results. As nurses provided more support, stress was reduced in the infants, and their self‐regulation during the bath was enhanced especially by the use of ‘containment’ and ‘positional support’. Conversely, non‐therapeutic caregiver behaviours including ‘rapid and rough handling’ of the baby, ‘chatting with other people’ and ‘inappropriate handling’ increased infant ‘stress’ during the bath.

Conclusion. The findings provide new information about the link between care‐giving and infant responses and how caregivers can better interact with preterm infants during a very sensitive period of brain development.

Relevance to clinical practice. How nurses take care of the preterm infants influences their responses to care‐giving stimuli. To interact better with the infant during care‐giving procedures, nurses need to provide more supportive care‐giving behaviours especially ‘position support’ and ‘containment’ based on the infant’s needs, and avoid care‐giving that may be too rough and occur too quickly without attending the baby’s stressful signals, positioning the baby in hyperextension posture, or chatting with other people during procedures.
Clinical trials: the challenge of recruitment and retention of participants
Authors: Gul Raisa B , Ali Parveen A
Published: December 2009

Aims and objectives.  This article, based on the available literature, attempts to discuss the importance of recruitment and retention of research participants, the associated barriers and challenges, and various strategies to overcome these barriers.

Background.  The inability to recruit and retain the required participants in a research project poses serious threats to both the internal and the external validity of a research study. Despite serious implications, the issues of recruitment and retention do not receive due attention in research and publications. Literature suggests a lack of coordinated efforts to collect information on the outcomes of recruitment experiences in clinical trials and population studies. Studies often mention the number of participants who refuse to participate; however, the majority of the studies often fail to mention the specific reasons insufficient recruitment or retention of the participants.

Design.  A methodological paper.

Method.  Various participant‐, context‐, environment‐ and research‐related factors are examined that affect the phenomenon of recruitment and retention of the participants in a study.

Results.  Delayed or inefficient recruitment also has financial and ethical implications. Although there are many pieces of information scattered throughout academic journals on recruitment and retention of participants in research, few authors have dealt with the issue holistically. It is imperative for researchers to understand the importance of recruitment and retention of research participants, the associated barriers and challenges, and various strategies to overcome these barriers.

Conclusion.  Appropriate recording and reporting of the problems faced while recruiting and retaining the participants in research studies can help not only in understating the challenge, but will also help in devising the strategies to overcome this problem. This article was an attempt to synthesise and review the available literature on recruitment and retention issues, which demand extensive theoretical and conceptual thinking as part of the research design.

Relevance to practice.  An understanding of the challenges and issues related to recruitment and retention can help researchers to think ahead about the strategies to overcome these issues and consequently save the time and energy of the participants, researchers and funding agencies.
Autoantibodies to Neurotrophic Receptors TrkA, TrkB and TrkC in Patients with Acute Chagas’ Disease
Authors: Lu B. , Luquetti A. O. , Rassi A. , PereiraPerrin M.
Published: December 2009

Neurotrophic receptors TrkA and TrkC double up as receptors that Trypanosoma cruzi uses to invade cells and as autoantigen in T. cruzi‐infected individuals (with Chagas’ disease). Consequently, autoantibodies against TrkA and TrkC (ATA) potently block T. cruzi invasion in vitro and in ATA‐immunized mice. Thus, ATA could keep T. cruzi invasion in check in Chagas’ disease. However, ATA has been examined only in patients with chronic Chagas’ disease. To determine whether ATA potentially participate in the early stage of infection, we analysed the sera of 15 patients with acute Chagas’ disease, 4–66 years of age. We find that all sera contain high antibody titres to TrkA, TrkB and TrkC, but not to other growth factor receptors, indicating that ATA are produced relatively soon after T. cruzi infection by an age‐independent process. One individual, who acquired the disease after an accidental laboratory infection, converted to Trk‐antibody (Ab)‐seronegative when progressing to the chronic phase. ATA from acute patients were of low avidity (K0 <24.8 × 10−8 m) and of IgM and IgA isotypes. In contrast, ATA from chronic patients were of high avidity (Ko = 1.4 to 4.5 × 10−8 m) and of the IgG2 isotype. Therefore, ATA underwent affinity maturation and class switch when patients progressed from acute to chronic disease. Thus, it may be that Trk autoimmunity, which starts in the acute Chagas’ disease, plays a role in attenuating parasitemia and tissue parasitism that characterizes the acute/chronic phase transition of Chagas’ disease.
Increased mucosal expression of GATA‐3 and STAT‐4 in pediatric ulcerative colitis
Authors: Ohtani Kiyotaka , Ohtsuka Yoshikazu , Ikuse Tamaki , Baba Yosuke , Yamakawa Yoko , Aoyagi Yo , Fujii Tohru , Kudo Takahiro , Nagata Satoru , Shimizu Toshiaki
Published: December 2009

Background:  Serum pro‐inflammatory cytokine levels are frequently elevated in the acute phase of pediatric inflammatory bowel disease (IBD). Because the role of pro‐inflammatory cytokine in the acute phase of pediatric IBD has not been well investigated, the serum levels of pro‐inflammatory cytokines and the expression of Th1 and Th2 signaling molecules in mucosa from the acute phase of pediatric IBD were examined.

Methods:  Twenty children with ulcerative colitis (UC; mean age, 9.95 ± 4.10 years) and 12 with Crohn's disease (CD; mean age, 10.0 ± 4.90 years) were enrolled for the serum cytokine (interleukin [IL]‐4, IL‐5, IL‐6, tumor necrosis factor‐α, tumor growth factor‐β1, and interferon‐γ) assay. Expression of T‐helper cell 1 (Th1) (T‐box expressed in T cells: T‐bet and signal transducer and activator of transcription‐4: STAT‐4) and Th2 (GATA‐3 and STAT‐6) signaling molecules was examined on real‐time polymerase chain reaction using mucosal samples from eight children in the acute phase of UC, eight with CD and eight controls.

Results:  Significant elevation of serum IL‐4 and IL‐6 levels was detected at the acute phase of pediatric UC and CD compared with levels at remission (P < 0.05 in each). The mucosal expression of GATA‐3 and STAT‐4 was significantly enhanced in the acute phase of pediatric UC compared with normal mucosa. No significant difference was observed in the expression of all examined molecules in the acute phase of pediatric CD.

Conclusions:  IL‐4 and its signaling molecule GATA‐3, as well as the Th1 signaling molecule STAT‐4, are involved in the pathogenesis of acute phase of pediatric UC.
ILLEGAL MUSIC DOWNLOADING AND ITS IMPACT ON LEGITIMATE SALES: AUSTRALIAN EMPIRICAL EVIDENCE
Authors: McKENZIE JORDI
Published: December 2009

This paper explores illegal music file‐sharing activity and its effect on Australian sales of singles in the physical and digital retail markets. Using fifteen weeks of Australian Recording Industry Association weekly chart rankings of physical and digital sales, combined with a proxy for download activity derived from the popular peer‐to‐peer (P2P) network Limewire, the evidence suggests no discernible impact of download activity on legitimate sales. Whilst significant negative correlation between chart rank and download activity is observed in the digital market, once download endogeneity is purged from the model and song heterogeneity is controlled for no significant relationship remains.
CORPORATE GOVERNANCE IN JAPAN AND THE UK: CODES, THEORY AND PRACTICE
Authors: Mizuno Mitsuru , Tabner Isaac T.
Published: December 2009

We reflect on the evolution of corporate governance and the role of institutional investors in enhancing governance in Japan and the UK. Japan places emphasis on stakeholder capitalism, whereas the UK places emphasis on shareholder capitalism. Nonetheless, in both countries, institutional investors have exerted significant influence on the evolution of corporate governance. Institutional investors in the UK have more power over company management than their Japanese counterparts, although it is alleged that these powers are not exercised to their best potential in either country.
WHY HAS TOP EXECUTIVE COMPENSATION INCREASED SO MUCH IN CHINA: A EXPLANATION OF PEER‐EFFECTS
Authors: Yang Ruilong , Yang Jidong
Published: December 2009

Top executive compensation can be affected significantly by peer group pay. This paper investigates the impact of peer effects on the change in top executive compensation based on evidence from China. Empirical results show that if the top three executives' compensation was lower than the peer group median level in year t − 1, the percentage change in the top three executives compensation in year t would be higher by 0.225%, and that the absolute level of pay would increase by 51 000 yuan. Furthermore, better performance, faster growth and state ownership increase the likelihood of peer effects, while corporate governance variables do not.
The Effect of Moderate to Heavy Alcohol Consumption on Neuropsychological Performance as Measured by the Repeatable Battery for the Assessment of Neuropsychological Status
Authors: Green Alisa , Garrick Therese , Sheedy Donna , Blake Helen , Shores Edwin Arthur , Harper Clive
Published: December 2009

Background: Excessive alcohol use is associated with damage to the structure and function of the brain and impairment of cognition and behavior. Traditional test batteries used to assess cognitive performance in alcoholics are extensive and costly, limiting their use across various clinical and research settings. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a relatively new instrument that attempts to overcome some of these limitations. As yet the individual effect of moderate to heavy alcohol consumption on RBANS performance has not been examined. The primary aim of this study was to explore and quantify differences in performance between controls and drinkers on the RBANS and to examine the influence of age, gender, and alcohol use patterns on test performance.

Methods: Data from a subset of “Using Our Brains” (UoB) donors (n = 28) still actively drinking and meeting criteria for moderate to heavy alcohol use (30 to 80 g of ethanol per day) (Harper, 1988) and 28 matched controls (age, education, and premorbid Intelligence Quotient) were compared.

Results: Participants in the alcohol group performed below the healthy control group on the visuospatial and immediate memory index, and also on the RBANS total scorep < 0.001 and showed a greater decline in RBANS scores from estimated cross‐sectional premorbid levels. There was a positive association between alcohol ingestion in the preceding 12 months and the language indexp < 0.03 and the semantic fluency subtest (p < 0.03). Age was negatively associated with story memory (p < 0.02), coding (p < 0.001), list recognition (p < 0.01), story recall (p < 0.03), and figure recall (p < 0.02).

Conclusion: Our results suggest that the RBANS is able to detect and characterize differences in verbal fluency, visuospatial skills, components of declarative memory, and psychomotor speed between healthy controls and moderate to heavy active alcohol users. Executive functions, commonly affected by alcoholism and not included in the RBANS, require assessment with additional measures.
Mechanisms of Postural Control in Alcoholic Men and Women: Biomechanical Analysis of Musculoskeletal Coordination During Quiet Standing
Authors: Sullivan Edith V. , Rose Jessica , Pfefferbaum Adolf
Published: December 2009

Background:  Excessive sway during quiet standing is a common sequela of chronic alcoholism even with prolonged sobriety. Whether alcoholic men and women who have remained abstinent from alcohol for weeks to months differ from each other in the degree of residual postural instability and biomechanical control mechanisms has not been directly tested.

Method:  We used a force platform to characterize center‐of‐pressure biomechanical features of postural sway, with and without stabilizing conditions from touch, vision, and stance, in 34 alcoholic men, 15 alcoholic women, 22 control men, and 29 control women. Groups were matched in age (49.4 years), general intelligence, socioeconomic status, and handedness. Each alcoholic group was sober for an average of 75 days.

Results:  Analysis of postural sway when using all 3 stabilizing conditions versus none revealed diagnosis and sex differences in ability to balance. Alcoholics had significantly longer sway paths, especially in the anterior–posterior direction, than controls when maintaining erect posture without balance aids. With stabilizing conditions the sway paths of all groups shortened significantly, especially those of alcoholic men, who demonstrated a 3.1‐fold improvement in sway path difference between the easiest and most challenging conditions; the remaining 3 groups, each showed a ∼2.4‐fold improvement. Application of a mechanical model to partition sway paths into open‐loop and closed‐loop postural control systems revealed that the sway paths of the alcoholic men but not alcoholic women were characterized by greater short‐term (open‐loop) diffusion coefficients without aids, often associated with muscle stiffening response. With stabilizing factors, all 4 groups showed similar long‐term (closed loop) postural control. Correlations between cognitive abilities and closed‐loop sway indices were more robust in alcoholic men than alcoholic women.

Conclusions:  Reduction in sway and closed‐loop activity during quiet standing with stabilizing factors shows some differential expression in men and women with histories of alcohol dependence. Nonetheless, enduring deficits in postural instability of both alcoholic men and alcoholic women suggest persisting liability for falling.
Common Genetic Contributions to Alcohol and Cannabis Use and Dependence Symptomatology
Authors: Sartor Carolyn E. , Grant Julia D. , Bucholz Kathleen K. , Madden Pamela A. F. , Heath Andrew C. , Agrawal Arpana , Whitfield John B. , Statham Dixie J. , Martin Nicholas G. , Lynskey Michael T.
Published: December 2009

Background:  Despite mounting evidence that use of and dependence on alcohol and cannabis are influenced by heritable factors, the extent to which heritable influences on these phenotypes overlap across the 2 substances has only rarely been explored. In the current study, we quantified cross‐substance overlap in sources of variance and estimated the degree to which within‐substance associations between use and dependence measures are attributable to common genetic and environmental factors for alcohol and cannabis.

Methods:  The sample was comprised of 6,257 individuals (2,761 complete twin pairs and 735 singletons) from the Australian Twin Registry, aged 24 to 36 years. Alcohol and cannabis use histories were collected via telephone diagnostic interviews and used to derive an alcohol consumption factor, a frequency measure for cannabis use, and DSM‐IV alcohol and cannabis dependence symptom counts. Standard genetic analyses were conducted to produce a quadrivariate model that provided estimates of overlap in genetic and environmental influences across the 4 phenotypes.

Results:  Over 60% of variance in alcohol consumption, cannabis use, and cannabis dependence symptoms, and just under 50% of variance in alcohol dependence (AD) symptoms were attributable to genetic sources. Shared environmental factors did not contribute significantly to the 4 phenotypes. Nearly complete overlap in heritable influences was observed for within‐substance measures of use and dependence symptoms. Genetic correlations across substances were 0.68 and 0.62 for use and dependence symptoms, respectively.

Conclusions:  Common heritable influences were evident for alcohol and cannabis use and for AD and cannabis dependence symptomatology, but findings indicate that substance‐specific influences account for the majority of the genetic variance in the cannabis use and dependence phenotypes. By contrast, the substantial correlations between alcohol use and AD symptoms and between cannabis use and cannabis dependence symptoms suggest that measures of heaviness of use capture much of the same genetic liability to alcohol‐ and cannabis‐related problems as dependence symptomatology.