bluuebunny/crossref_metadata_2025_split huggingface dataset:
REGULATION OF RYANODINE RECEPTORS FROM SKELETAL AND CARDIAC MUSCLE DURING REST AND EXCITATION
Authors: Laver DR 
Published: October 2006

SUMMARY

In muscle, intracellular calcium concentration, hence skeletal muscle force and cardiac output, is regulated by uptake and release of calcium from the sarcoplasmic reticulum (SR). The ryanodine receptor (RyR) forms the calcium release channel in the SR.
Calcium release through RyRs is modulated by a wide variety of endogenous molecules, including small diffusible ligands such as ATP, Ca2+ and Mg2+. The regulation of RyR channels by ATP, Ca2+ and Mg2+ is a complex interplay of several regulatory mechanisms, which are still being unravelled. Consequently, it is not clearly known how RyRs are regulated in resting muscle and during contraction.
The present paper reviews factors controlling the activity of RyRs in skeletal and cardiac muscle with an emphasis on mechanistic insights derived from single channel recording methods.
In addition, the nature of dihydropyridine receptor (DHPR) control of RyRs in skeletal muscle derived from experiments with peptide fragments of the DHPR II–III loop is reviewed.
Finally, recent experiments on coupled RyRs in lipid bilayers and their potential for resolving the elusive mechanisms controlling calcium release during cardiac contraction are discussed.
Sleep–wake cycles in obese children with and without binge‐eating episodes
Authors: Tzischinsky Orna , Latzer Yael 
Published: October 2006

Aim:  The aim of the study was to assess binge‐eating episodes and to characterise sleep–wake cycles among obese children.Method:  The obese group consisted of 36 children. All participants received a diagnosis of primary obesity. The obese group was subdivided into two groups: obese with binge eating and without binge eating. A normal‐weight control group was comprised of 25 normal‐weight children. Sleep–wake patterns were monitored for 1 week, using mini‐actigraphs and self‐report questionnaires.Results:  Thirty‐seven per cent of the obese children reported uncontrolled binge‐eating episodes. Actigraphic monitoring revealed significant differences in sleep quality between all three groups. Self‐report questionnaires presented significantly more sleep disturbances in the obese group with binge eating and obese group without binge eating than in the normal‐weight group.Conclusion:  Sleep disruption in obese children with binge eating is significantly more severe than in both obese non‐binge‐eating children and normal‐weight controls.
Diagnosis of foetal alcohol syndrome and alcohol use in pregnancy: A survey of paediatricians’ knowledge, attitudes and practice
Authors: Elliott Elizabeth J , Payne Jan , Haan Eric , Bower Carol 
Published: October 2006

Aim:  To measure paediatricians’ knowledge, attitudes and practices regarding foetal alcohol syndrome (FAS) and alcohol use during pregnancy.Methods:  Postal survey of paediatricians in Western Australia in 2004. Of 179 eligible paediatricians, 132 (73.7%) responded (90 consultant paediatricians and 42 paediatric trainees).Results:  Of the 132 respondents, 18.9% identified all four essential diagnostic features for FAS. Only 49.2% had previously diagnosed FAS (range 1–30 cases) but 91.7% had seen children diagnosed by others; 76.5% had suspected but not diagnosed FAS; 12.1% had been convinced of but not recorded the diagnosis; and 31.8% had referred children for diagnostic confirmation. Although 79.6% agreed early diagnosis might be advantageous, 69.6% said diagnosis might be stigmatising and 36.4% thought parents might resist referral for assessment and treatment. Although 78.2% agreed avoiding binge drinking may reduce FAS, only 43.9% believed women should abstain from using alcohol in pregnancy. Only 4.5% felt very prepared to deal with a patient with FAS: most wanted educational materials for themselves (69.7%) and child carers (71.2%). Only 23.3% routinely ask about alcohol use when taking a pregnancy history and 4.2% routinely provide information on the consequences of alcohol use. Only 11.4% had read the current Australian national health guideline regarding alcohol consumption in pregnancy and 9.1% provided advice consistent with the guideline.Conclusion:  Paediatricians identified the need for educational materials about FAS and alcohol use in pregnancy for themselves and their clients. Lack of knowledge about FAS diagnosis and management will limit opportunities for diagnosis, prevention and early intervention.
Caring for adolescents with mental health problems: Challenges in the emergency department
Authors: Stewart Claire , Spicer Maureen , Babl Franz E 
Published: October 2006

Aim:  To explore management issues in adolescents with mental health problems who presented to a children’s hospital emergency department (ED).Methods:  Retrospective chart review of all mental health presentations of adolescents (12–18 years) to a tertiary children’s hospital ED, over a 1‐year period (2003–2004). Patients were identified based on a search of the electronic ED log. Medical and mental health records were manually abstracted.Results:  There were 203 presentations during the study period. Eighteen per cent of patients presented more than once. Mean age was 14.7 years, 73% were female and 67% presented after 6 pm. Fifty‐seven per cent presented with non‐accidental overdose, self‐harm or suicide risk. There were 110 security incidents in 26% of presentations during the ED stay. A total of 47% were admitted, 27% to the medical inpatient service and 20% to a psychiatric inpatient facility.Conclusion:  Adolescent mental health presentations to the ED require a high number of ED, mental health and inpatient service resources. Security incidents occur frequently. We propose changes to address identified problems. These include redesigning the physical structure of the ED, more mental health training and support for ED staff, better access to mental health records and crisis plans for adolescents at risk, and improved after‐hours mental health services for children and adolescents.
Evaluation of renal tubular function in children taking anti‐epileptic treatment
Authors: UNAY BULENT , AKIN RIDVAN , SARICI S UMIT , GOK FAYSAL , KURT ISMAIL , GOKCAY ERDAL 
Published: October 2006

SUMMARY:Aim:  To assess the effects of anti‐epileptic drugs on renal tubular function.Methods:  Urinary N‐acetyl‐β‐D‐glucosaminidase activity was measured in 114 epileptic children (mean age 5.6 ± 1.1 years) who were undergoing monotherapy with valproate (n = 46), carbamazepine (n = 34), lamotrigine (n = 13) and combined therapy with valproate+carbamazepine (n = 21).Results:  The urinary N‐acetyl‐β‐D‐glucosaminidase index of valproate (P < 0.01), carbamazepine (P < 0.05) and polytherapy group (P < 0.01) were significantly elevated when compared with that of the control group. No significant difference in N‐acetyl‐β‐D‐glucosaminidase levels was found between the lamotrigine group and the control subjects. We found that the distribution of the N‐acetyl‐β‐D‐glucosaminidase values of patients depended significantly on the length of therapy (P < 0.01). The level of urinary excretion of N‐acetyl‐β‐D‐glucosaminidase was significantly higher in the patients who were taking long‐term treatment (>10 years) with valproate, carbamazepine and combined therapy than those taking therapy shorter than 10 years (P < 0.01). The mean serum concentrations of valproate and carbamazepine were 68.7 ± 17.44 µg/mL and 5.41 ± 1.23 µg/mL, respectively. There was a significant correlation between the serum concentration of valproate and urinary N‐acetyl‐β‐D‐glucosaminidase levels (r = 0.44, P < 0.01). There was also a significant correlation between the serum concentration of carbamazepine and N‐acetyl‐β‐D‐glucosaminidase excretion (r = 0.52, P < 0.01).Conclusion:  The present study demonstrated that in patients treated with valproate and carbamazepine, an impairment of tubular function can be present, whereas lamotrigine does not cause any significant change.
Intrapleural heparin or heparin combined with human recombinant DNase is not effective in the treatment of empyema in a rabbit model
Authors: DIKENSOY Oner , ZHU Zhiwen , NA Moon Jun , LIAO Huai , DONNELLY Edwin , LIGHT Richard W. 
Published: October 2006

Objective and background:  The aim of this study was to investigate the effectiveness of intrapleural heparin or heparin combined with human recombinant DNase in the treatment of empyema.Methods:  Empyema was induced in rabbits with an intrapleural injection of 109Pasteurella multicoda organisms in infusion agar via a surgically placed chest tube. Once empyema was verified, a blinded investigator administered drugs via the chest tube. There were three treatment groups each with six rabbits. One group was given 1000 IU heparin, a second group was given 1000 IU heparin plus 1 mg of human recombinant DNase via chest tube and the control group received saline. The rabbits received treatment every 12 h for a total of six treatments and the volume of each treatment was 3 mL. The animals were sacrificed at day 10 and the amount of empyema and pleural thickening was scored macroscopically on a scale of 0–6.Results:  The total volume of pleural effusion aspirated was significantly higher in the heparin group (25.8 ± 10.7 mL) compared with either saline (8 ± 8.9) or heparin plus human recombinant DNase (6.8 ± 6.1) groups (P = 0.003). The mean empyema and pleural thickening scores did not differ significantly between the groups (P = 0.8, P = 0.5 respectively). A weak correlation was found between total volume of aspirated pleural fluid and pleural parameters of white blood cell counts and LDH levels (r = 0.546 and P = 0.02, r = 0.631 and P = 0.02 respectively).Conclusion:  The intrapleural administration of 1000 IU heparin alone or in combination with 1 mg of human recombinant DNase is no more effective than saline in the treatment of empyema in rabbits. Intrapleural heparin significantly increased the drainage of pleural fluid compared with the combination and saline group.
The effects of adulthood olanzapine treatment on cognitive performance and neurotrophic factor content in male and female rats neonatally treated with quinpirole
Authors: Thacker Stephanie K. , Perna Marla K. , Ward Jeffery J. , Schaefer Tori L. , Williams Michael T. , Kostrzewa Richard M. , Brown Russell W. 
Published: October 2006

AbstractMale and female Sprague–Dawley rats were administered quinpirole (1 mg/kg, i.p.) or saline once daily from postnatal day (P)1 to P21. This drug treatment has been shown to produce long‐term priming of the D2 receptor. Beginning on P62, rats were administered the atypical antipsychotic olanzapine (2.5 mg/kg) or saline twice daily (i.p.) for 28 days. One day after olanzapine treatment ceased, rats were tested on the place and match‐to‐place versions of the Morris water maze (MWM) for seven consecutive days. Dopamine D2 receptor priming was verified through a yawning behavioural test, a D2 receptor‐mediated event, before olanzapine was administered as well as after olanzapine treatment and behavioural testing were complete. Results showed that neonatal quinpirole treatment induced D2 priming that was eliminated by olanzapine treatment. On the MWM place version, D2‐primed rats demonstrated a significant impairment that was eliminated by olanzapine treatment, but olanzapine treatment to animals neonatally treated with saline produced a significant deficit on the place version of the MWM. There were no significant deficits on the match‐to‐place version. Brain tissue analyses revealed that neonatal quinpirole treatment produced a significant decrease in hippocampal NGF, BDNF and ChAT that was eliminated by olanzapine treatment. Neonatal quinpirole treatment produced a significant decrease in BDNF and ChAT in the frontal cortex that was unaffected by olanzapine treatment. These results show that olanzapine eliminates D2 receptor priming and cognitive impairment and also alleviates decreases in neurotrophins and acetylcholinergic markers produced by D2 priming in the hippocampus.
5‐HT1B receptor‐mediated presynaptic inhibition at the calyx of Held of immature rats
Authors: Mizutani Haruo , Hori Tetsuya , Takahashi Tomoyuki 
Published: October 2006

Abstract5‐Hydroxytryptamine (5‐HT) inhibits transmitter release via activating GTP‐binding proteins, but the target of 5‐HT receptors in the nerve terminal is not determined. We addressed this question at the calyx of Held synapse in the brainstem slice of immature rats. Bath‐application of 5‐HT attenuated the amplitude of nerve‐evoked excitatory postsynaptic currents (EPSCs) associated with an increase in the paired‐pulse ratio, whereas it had no effect on the amplitude of spontaneous miniature EPSCs. The 5‐HT1B receptor agonist CP93129 mimicked the inhibitory effect of 5‐HT, but the 5‐HT1A agonist (R)‐(+)‐8‐hydroxy‐DPAT (8‐OHDPAT) had no effect. The 5‐HT1B receptor antagonist NAS‐181 blocked the inhibitory effect of 5‐HT. These results suggest that 5‐HT activated 5‐HT1B receptors in calyceal nerve terminals, thereby inhibiting transmitter release. In direct whole‐cell recordings from calyceal nerve terminals, 5‐HT attenuated voltage‐dependent Ca2+ currents, but had no effect on voltage‐dependent K+ currents. When EPSCs were evoked by presynaptic Ca2+ currents during simultaneous pre‐ and postsynaptic recordings, the magnitude of the 5‐HT‐induced inhibition of Ca2+ currents fully explained that of EPSCs. Upon repetitive applications, 5‐HT showed tachyphylaxis, with its effect on both EPSCs and presynaptic Ca2+ currents becoming weaker in the second application. 1,2‐bis(o‐aminophenoxy)ethane‐N‐N′‐N′‐N′‐tetraacetic acid (BAPTA; 10 mm) loaded into the nerve terminal abolished this tachyphylaxis. The presynaptic inhibitory effect of 5‐HT was prominent at postnatal day 5, but became weaker as animals matured. We conclude that activation of 5‐HT1B receptors inhibits voltage‐gated Ca2+ channels, thereby inhibiting transmitter release at immature calyceal nerve terminals, and that 5‐HT1B receptors undergo Ca2+‐dependent tachyphylaxis on repetitive activations.
Zinc neurotoxicity is dependent on intracellular NAD+ levels and the sirtuin pathway
Authors: Cai Ai‐Li , Zipfel Gregory J. , Sheline Christian T. 
Published: October 2006

AbstractZinc neurotoxicity has been demonstrated in ischemic, seizure, hypoglycemic, and trauma‐induced neuronal death where Zn2+ is thought to be synaptically released and taken up in neighbouring neurons, reaching toxic concentrations. We previously demonstrated that toxicity of extracellular Zn2+ depended on entry, elevation in intracellular free Zn2+ ([Zn2+]i), a reduction in NAD+ and ATP levels, and dysfunction of glycolysis and cellular metabolism. We suggested that PARP‐1 activation alone can not explain this loss of neuronal NAD+. NAD+ was recently demonstrated to permeate neurons and glia, and we have now shown that exogenous NAD+ can reduce Zn2+ neurotoxicity, and 3‐acetylpyridine, which generates inactive NAD+, potentiated Zn2+ neurotoxicity. Sirtinol and 2‐hydroxynaphthaldehyde, inhibitors of the sirtuin pathway (SIRT proteins are NAD+‐catabolic protein deacetylases), attenuated both acute and chronic Zn2+ neurotoxicity. Resveratrol and fisetin (sirtuin activators) potentiated NAD+ loss and Zn2+ neurotoxicities. Furthermore, neuronal cultures derived from the Wlds mouse, which overexpress the NAD+ synthetic enzyme nicotinamide mononucleotide adenyl transferase (NMNAT‐1), had reduced sensitivity to Zn2+ neurotoxicity. Finally, nicotinamide was demonstrated to attenuate CA1 neuronal death after 10 min of global ischemia in rat even if administered 1 h after the insult. Together with previous data, these results further implicate NAD+ levels in Zn2+ neurotoxicity.
A distinct anatomical network of cortical areas for analysis of motion in far peripheral vision
Authors: Palmer S. M. , Rosa M. G. P. 
Published: October 2006

AbstractWe defined cortical areas involved in the analysis of motion in the far peripheral visual field, a poorly understood aspect of visual processing in primates. This was accomplished by small tracer injections within and around the representations of the monocular field of vision (‘temporal crescents’) in the middle temporal area (MT) of marmoset monkeys. Quantitative analyses demonstrate that the representation of the far periphery receives specific connections from the retrosplenial cortex (areas 23v and prostriata), as well as comparatively stronger inputs from the primary visual area (V1) and from areas surrounding MT (in particular, the medial superior temporal area, MST). In contrast, the far peripheral representation receives little or no input from most other extrastriate areas, including the second visual area (V2), the densely myelinated areas of the dorsomedial cortex, and ventral stream areas; these areas are shown to have robust projections to other parts of MT. Our results demonstrate that the responses of cells in different parts of a same visual area can be determined by different combinations of synaptic inputs, in terms of areas of origin. They also suggest that the interconnections responsible for motion processing in the far periphery of the visual field convey information that is crucial for rapid‐response aspects of visual function such as orienting, postural and defensive reactions.
Bottom‐up, not top‐down, modulation of imitation by human and robotic models
Authors: Press Clare , Gillmeister Helge , Heyes Cecilia 
Published: October 2006

AbstractVisual observation of human actions provokes more motor activation than observation of robotic actions. We investigated the extent to which this visuomotor priming effect is mediated by bottom‐up or top‐down processing. The bottom‐up hypothesis suggests that robotic movements are less effective in activating the ‘mirror system’ via pathways from visual areas via the superior temporal sulcus to parietal and premotor cortices. The top‐down hypothesis postulates that beliefs about the animacy of a movement stimulus modulate mirror system activity via descending pathways from areas such as the temporal pole and prefrontal cortex. In an automatic imitation task, subjects performed a prespecified movement (e.g. hand opening) on presentation of a human or robotic hand making a compatible (opening) or incompatible (closing) movement. The speed of responding on compatible trials, compared with incompatible trials, indexed visuomotor priming. In the first experiment, robotic stimuli were constructed by adding a metal and wire ‘wrist’ to a human hand. Questionnaire data indicated that subjects believed these movements to be less animate than those of the human stimuli but the visuomotor priming effects of the human and robotic stimuli did not differ. In the second experiment, when the robotic stimuli were more angular and symmetrical than the human stimuli, human movements elicited more visuomotor priming than the robotic movements. However, the subjects' beliefs about the animacy of the stimuli did not affect their performance. These results suggest that bottom‐up processing is primarily responsible for the visuomotor priming advantage of human stimuli.
Type 1 diabetes as a risk factor for stroke in men and women aged 15–49: a nationwide study from Sweden
Authors: Sundquist K. , Li X. 
Published: October 2006

AbstractAims  The main objective was to determine premature stroke risk in men and women in Sweden with previous hospital admission for Type 1 diabetes or without previous hospital admission.Methods  All individuals in Sweden aged 15–34 years at first hospital admission for Type 1 diabetes and aged 15–49 years at first hospital admission for stroke during the study period (1987–2001) were identified. Standardized incidence ratios (SIRs) were calculated to compare premature stroke risk between individuals admitted to hospital with Type 1 diabetes and individuals without hospital admission, after controlling for age, time period, occupation and geographical region. SIRs were also calculated for individuals with diabetic complications.Results  The overall SIRs for premature stroke in men and women with hospital admission for Type 1 diabetes were 17.94 [95% confidence interval (CI) 12.87, 24.36] and 26.11 (95% CI 18.81, 35.32), respectively. Men and women with diabetic nephropathy had the highest significant SIRs of premature stroke: 48.87 and 73.53, respectively.Conclusions  Our data indicate that young to middle‐aged individuals with Type 1 diabetes had a considerably higher risk of premature stroke than those without Type 1 diabetes. This underscores the need to implement vigorous interventions in healthcare settings in order to decrease the risk of premature stroke in individuals with Type 1 diabetes.
How do parents perceive their adolescent's diabetes: a qualitative study
Authors: Carroll Aaron E. , Marrero David G. 
Published: October 2006

AbstractBackground/aims  The developmental tasks of adolescence, combined with physical changes, can interfere with self‐management behaviour. Yet little is known about how parents view these challenges as they attempt to help their children cope with diabetes. Our objective was to understand how living with an adolescent with diabetes influences parents’ perceptions of their child's well‐being, their relationship with their child, and how they perceive the influence of peers and school on their child's diabetes.Methods  Twenty‐eight parents of adolescents with Type 1 diabetes, aged 13–18 years, participated in focus groups. Transcripts were analysed using qualitative methods to determine dominant themes and incidence density.Results  Themes included how diabetes negatively influences their adolescent's lifestyle, how diabetes makes it difficult for parents to understand developmental challenges experienced by their child, concerns regarding the potential to develop long‐term complications, perceptions on how diabetes impacts on their relationship with their child and relationships with peers and how their children's school impacts on their diabetes self‐managementConclusions  This qualitative focus group study provides insight into parental perceptions of adolescents living with Type 1 diabetes, specifically as it relates to lifestyle implications, relationships with parents, peers and physicians, and school experiences.
Food habits, energy and nutrient intake in adolescents with Type 1 diabetes mellitus
Authors: Lodefalk M. , Åman J. 
Published: October 2006

Abstract1Aims  The aims were to describe the food habits of adolescents with Type 1 diabetes (Type 1 DM) and to compare them with healthy control subjects; to describe the distribution of energy‐providing nutrients in patients and compare it with current recommendations and previous reports; and finally, to investigate associations between dietary intake and glycaemic control.Methods  One hundred and seventy‐four adolescents with Type 1 DM and 160 age‐ and sex‐matched healthy control subjects completed a validated food frequency questionnaire, and 38 randomly chosen patients completed a prospective 4‐day food record.Results  Patients ate more regularly, and more often ate fruit and fruit juice, potatoes and root vegetables, meat, fish, egg, offal and sugar‐free sweets than control subjects. Control subjects more often ate ordinary sweets and snacks. Patients chose coarse rye bread and dairy products with less fat to a greater extent than control subjects. Patients were heavier than control subjects. The intake of saturated fat was higher in patients compared with recommendations and, for boys with diabetes, the intake of protein was higher than recommended. Patients with poorer glycaemic control ate vegetables, fruit and fish less often than patients with better control.Conclusions  The food habits of adolescents with Type 1 DM were healthier than those of control subjects. The intake of energy‐providing nutrients was in line with current recommendations and showed improvements compared with previous reports, with the exception of fibre intake. The association between dietary intake and glycaemic control needs further investigation in prospective studies.