bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intact fibula improves fracture healing in a rat tibia osteotomy model
Authors: Shefelbine Sandra J. , Augat Peter , Claes Lutz , Beck Alexander 
Published: October 2004

AbstractRat tibia fractures are often used in fracture healing studies. Usually the fracture is stabilized with an intramedullary pin, which provides bending stiffness, but little torsional stiffness. The objective of this research was to determine the in vitro torsional rigidity of an osteotomized tibia with and without the fibula, and to determine if this difference influences the healing process in vivo. In vitro eleven rat tibias received an osteotomy, were stabilized with an intramedullary pin, and were tested in internal rotation to determine the torsional rigidity. The fibula was then manually broken and the torsional rigidity measured again. In vivo 18 rats received a tibial osteotomy, eight of which had an additional fractured fibula. After three weeks, the rats were sacrificed and the tibias were analyzed. Bone density in the fracture callus was measured with qCT. Bending rigidity and maximum breaking moment were determined in three‐point bending. In vitro testing demonstrated that the torsional rigidity with an intact fibula was nearly two times higher than when the fibula was fractured. Though the torsional rigidity was still small in comparison with an intact bone, it resulted in a significantly different healing process in vivo. Rats with intact fibulas had significantly higher bone mineral density, bending rigidity, and maximum breaking moment compared to rats with a fractured fibula. These results indicate that torsional stability considerably affects the healing process. In a fracture model, it is critical to characterize the mechanical environment of the fracture. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Molecular barcodes detect redundancy and contamination in hairpin-bisulfite PCR
Authors: Miner Brooks E. , Stöger Reinhard J. , Burden Alice F. , Laird Charles D. , Hansen R. Scott 
Published: October 2004

Abstract
PCR amplification of limited amounts of DNA template carries an increased risk of product redundancy and contamination. We use molecular barcoding to label each genomic DNA template with an individual sequence tag prior to PCR amplification. In addition, we include molecular ‘batch-stamps’ that effectively label each genomic template with a sample ID and analysis date. This highly sensitive method identifies redundant and contaminant sequences and serves as a reliable method for positive identification of desired sequences; we can therefore capture accurately the genomic template diversity in the sample analyzed. Although our application described here involves the use of hairpin-bisulfite PCR for amplification of double-stranded DNA, the method can readily be adapted to single-strand PCR. Useful applications will include analyses of limited template DNA for biomedical, ancient DNA and forensic purposes.
Regional Differences in Neurogenic Signal Transduction Pathway of Cholera Toxin‐Induced Fluid, Electrolyte and Serotonin Accumulation in the Porcine Jejunum
Authors: Berggreen Paul , Grøndahl Marie Louise , Ersbøll Anette Kjær , Maltbæk Jørgen Strange , Thorbøll Jens Erik , Skadhauge Erik , Hansen Mark Berner 
Published: October 2004

Abstract:Serotonin, acetylcholine and substance P are mediators involved in the secretory response to cholera toxin in the small intestine. The aim of this study was to investigate the regional difference in the effect of a serotonin receptor type 3 antagonist (ondansetron), a nicotinic receptor antagonist (hexamethonium), and a substance P antagonist (the neurokinin receptor type 1 antagonist, CP 99,994) on the cholera toxin‐induced fluid accumulation in the porcine jejunum. A dose‐range of cholera toxin (0.32–56.00 μg/loop) was instilled for 4 hr in ligated loops in two regions of the proximal jejunum in 6–8‐week‐old pigs. Ondansetron (200 μg/kg), hexamethonium (10 mg/kg), CP 99,994 (1 mg/kg), or saline alone (control) were given intravenously 10 min. before cholera toxin instillation. Cardiovascular parameters, blood gas data, net fluid accumulation, serotonin and electrolyte concentration in the accumulated fluid were measured. Cardiovascular and blood gas parameters were within the normal range in all treatments. The apparent maximal response in fluid accumulation was reduced 20% in case of ondansetron, and by 33% using CP 99,994 in the aboral region compared to control, whereas no effect was observed in the oral region. Hexamethonium reduced the apparent maximal secretory response in both the oral and aboral regions by 45%. None of the treatments with antagonists changed the luminal content of serotonin or the electrolyte concentrations in the accumulated fluid. The results demonstrate that the involvement of serotonin receptor type 3 and neurokinin type 1 receptors in the transductional pathway of cholera toxin‐induced fluid accumulation vary significantly within the jejunum, while the cholinergic (nicotinic) transmission plays an even role.
Protective Role of Metallothionein on DNA Damage in Rat Kidney Caused by Cis‐Diamminedichloroplatinum
Authors: Hosokawa Toshiyuki , Okabe Masashi , Saito Shigeru , Saito Takeshi , Kurasaki Masaaki 
Published: October 2004

Abstract:Cis‐diamminedichloroplatinum (cis‐DDP) has been used as an anticancer agent but it also causes nephrotoxicity. To study the cis‐DDP metabolism and its effects, the induction of metallothioneins and DNA damage caused by cis‐DDP were observed. Cis‐DDP or trans‐DDP was administered to seven‐week‐old Wistar male rats as three daily injections of 8.0 mg/kg body wt., intraperitoneally. Using the obtained kidneys, gel filtration assay, metal analysis, immunohistochemistry and terminal deoxy transferase‐mediated deoxy uracil triphosphate nick end labeling (TUNEL) method were carried out to examine localization of metallothioneins and DNA damage caused by cis‐DDP. Platinum (Pt) contents, 26.05±12.01 μg/g body wt. and 51.29±4.59 μg/g body wt. (average±S.E.) were detected in the kidney of rats injected with both cis‐ and trans‐DDP, respectively. Metallothionein was detected in the cortex of the kidney in rats administrated cis‐DDP or trans‐DDP. The mRNA was also detected in the same region. On the other hand cis‐DDP showed induction of DNA damage on the cells in the outer stripe of the outer medulla but trans‐DDP did not show any damage. The region‐induced DNA damage differed from that induced by metallothioneins. Cis‐DDP is suggested to be mainly trapped at the proximal tubules by metallothioneins, and the rest of cis‐DDP induces DNA damage at the outer stripe of the outer medulla. Metallothioneins are considered to contribute to the protection against cis‐DDP in the rat cortex.
Amiodarone for Rapid Cardioversion of Chronic Atrial Tachyarrhythmia?
Authors: Nielsen Klaus Damkjær , Møller Søren 
Published: October 2004

Abstract:Electrical cardioversion of atrial tachyarrhythmia has disadvantages, such as the need for general anaesthesia, skin burns and thoracic pain. Pharmacodynamic cardioversion is without these side effects, but the reports of the efficacy of the treatment vary a lot. Amiodarone has been the only drug so far reported to give a combination of high efficacy and low frequency of serious side effects such as ventricular tachycardia and shock. The purpose of the present study was to assess the effect of amiodarone on chronic atrial tachycardia. Seventeen patients with chronic atrial fibrillation or flutter were given an oral dose of 30 mg/kg amiodarone. Serial blood tests after amiodarone ingestion were taken to document absorption. Patients, who did not convert to sinus rhythm within 24 hr were treated by electrical cardioversion. No patients converted pharmacodynamically to sinus rhythm. Twelve patients (71%) reached the recommended serum concentration of amiodarone (2–2.5 mg/l, median 2.4 mg/l, range 0.96–4.7). The concentration of desethylamiodarone remained low (<0.2 mg/l), and there were no objective or subjective side effects following the treatment. Sixteen patients (94%) were converted to sinusrhythm the day after by electrical cardioversion without complications. A single high dose of amiodarone is a safe but ineffective method of converting chronic atrial fibrillation and flutter, and may be used as adjuvant therapy in combination with electrical cardioversion.
Associations between carbon isotope ratios of ecosystem respiration, water availability and canopy conductance
Authors: McDowell N. G. , Bowling D. R. , Schauer A. , Irvine J. , Bond B. J. , Law B. E. , Ehleringer J. R. 
Published: October 2004

AbstractWe tested the hypothesis that the stable carbon isotope signature of ecosystem respiration (δ13CR) was regulated by canopy conductance (Gc) using weekly Keeling plots (n=51) from a semiarid old‐growth ponderosa pine (Pinus ponderosa) forest in Oregon, USA. For a comparison of forests in two contrasting climates we also evaluated trends inδ13CRfrom a wet 20‐year‐old Douglas‐fir (Pseudotsuga menziesii) plantation located near the Pacific Ocean. Intraannual variability inδ13CRwas greater than 8.0‰ at both sites, was highest during autumn, winter, and spring when rainfall was abundant, and lowest during summer drought. Theδ13CRof the dry pine forest was consistently more positive than the wetter Douglas‐fir forest (mean annualδ13CR: −25.41‰ vs. −26.23‰, respectively,P=0.07). At the Douglas‐fir forest,δ13CR–climate relationships were consistent with predictions based on stomatal regulation of carbon isotope discrimination (Δ). Soil water content (SWC) and vapor pressure deficit (vpd) were the most important factors governingδ13CRin this forest throughout the year. In contrast,δ13CRat the pine forest was relatively insensitive toSWCorvpd, and exhibited a smaller drought‐related enrichment (∼2‰) than the enrichment observed during drought at the Douglas‐fir forest (∼5‰). Groundwater access at the pine forest may buffer canopy–gas exchange from drought. Despite this potential buffering,δ13CRat the pine forest was significantly but weakly related to canopy conductance (Gc), suggesting thatδ13CRremains coupled to canopy–gas exchange despite groundwater access. During drought,δ13CRwas strongly correlated with soil temperature at both forests. The hypothesis that canopy‐level physiology is a critical regulator ofδ13CRwas supported; however, belowground respiration may become more important during rain‐free periods.
Divergent pheromone‐mediated insect behaviour under global atmospheric change
Authors: Mondor Edward B. , Tremblay Michelle N. , Awmack Caroline S. , Lindroth Richard L. 
Published: October 2004

AbstractWhile the effects of global atmospheric changes on vegetation and resulting insect populations(‘bottom‐up interactions’) are being increasingly studied, how these gases modify interactions among insects and their natural enemies (‘top‐down interactions’) is less clear. As natural enemy efficacy is governed largely by behavioural mechanisms, altered prey finding and prey defence may change insect population dynamics. Here we show that pheromone‐mediated escape behaviours, and hence the vulnerability of insects to natural enemies, are divergent under atmospheric conditions associated with global climate change. Chaitophorus stevensis, a common aphid on trembling aspen trees, Populus tremuloides, have diminished escape responses in enriched carbon dioxide (CO2) environments, while those in enriched ozone (O3) have augmented escape responses, to alarm pheromone. These results suggest that divergent pheromone‐mediated behaviours could alter predator–prey interactions in future environments.
Paired comparisons of carbon exchange between undisturbed and regenerating stands in four managed forests in Europe
Authors: Kowalski Andrew S. , Loustau Denis , Berbigier Paul , Manca Giovanni , Tedeschi Vanessa , Borghetti Marco , Valentini Riccardo , Kolari Pasi , Berninger Frank , Rannik Üllar , Hari Pertti , Rayment Mark , Mencuccini Maurizio , Moncrieff John , Grace John 
Published: October 2004

AbstractThe effects of harvest on European forest net ecosystem exchange (NEE) of carbon and its photosynthetic and respiratory components (GPP (gross primary production) and TER (total ecosystem respiration)) were examined by comparing four pairs of mature/harvested sites in Europe via a combination of eddy covariance measurements and empirical modeling. Three of the comparisons represented high coniferous forestry (spruce in Britain, and pines in Finland and France), while a coppice‐with‐standard oak plantation was examined in Italy.While every comparison revealed that harvesting converted a mature forest carbon sink into a carbon source of similar magnitude, the mechanisms by which this occurred were very different according to species or management practice. In Britain, Finland, and France the annual sink (source) strength for mature (clear‐cut) stands was estimated at 496 (112), 138 (239), and 222 (225) g C m−2, respectively, with 381 (427) g C m−2 for the mature (coppiced) stand in Italy. In all three cases of high forestry in Britain, Finland, and France, clear‐cutting crippled the photosynthetic capacity of the ecosystem – with mature (clear‐cut) GPP of 1970 (988), 1010 (363), and 1600 (602) g C m−2– and also reduced ecosystem respiration to a lesser degree – TER of 1385 (1100), 839 (603), and 1415 (878) g C m−2, respectively. By contrast, harvesting of the coppice oak system provoked a burst in respiration – with mature (clear‐cut) TER estimated at 1160 (2220) gC m−2– which endured for the 3 years sampled postharvest. The harvest disturbance also reduced GPP in the coppice system – with mature (clear‐cut) GPP of 1600 (1420) g C m−2– but to a lesser extent than in the coniferous forests, and with near‐complete recovery within a few years. Understanding the effects of harvest on the carbon balance of European forest systems is a necessary step towards characterizing carbon exchange for timberlands on large scales.
Spatial and temporal variability in forest–atmosphere CO2 exchange
Authors: Hollinger D. Y. , Aber J. , Dail B. , Davidson E. A. , Goltz S. M. , Hughes H. , Leclerc M. Y. , Lee J. T. , Richardson A. D. , Rodrigues C. , Scott N.A. , Achuatavarier D. , Walsh J. 
Published: October 2004

AbstractSeven years of carbon dioxide flux measurements indicate that a ∼90‐year‐old spruce dominated forest in Maine, USA, has been sequestering 174±46 g C m−2 yr−1 (mean±1 standard deviation, nocturnal friction velocity (u*) threshold >0.25 m s−1). An analysis of monthly flux anomalies showed that above‐average spring and fall temperatures were significantly correlated with greater monthly C uptake while above‐average summer temperatures were correlated with decreased net C uptake. Summer months with significantly drier or wetter soils than normal were also characterized by lower rates of C uptake. Years with above‐average C storage were thus typically characterized by warmer than average spring and fall temperatures and adequate summer soil moisture.Environmental and forest–atmosphere flux data recorded from a second tower surrounded by similar forest, but sufficiently distant that flux source regions (‘footprints’), did not overlap significantly showed almost identical temperature and solar radiation conditions, but some differences in energy partitioning could be seen. Half‐hourly as well as integrated (annual) C exchange values recorded at the separate towers were very similar, with average annual net C uptake differing between the two towers by <6%. Interannual variability in net C exchange was found to be much greater than between tower variability. Simultaneous measurements from two towers were used to estimate flux data uncertainty from a single tower. Carbon‐flux model parameters derived independently from each flux tower data set were not significantly different, demonstrating that flux towers can provide a robust method for establishing C exchange model parameters.
Management of tongue‐tie in children: A survey of paediatric surgeons in Australia
Authors: Brinkmann S , Reilly S , Meara JG 
Published: October 2004

Objectives:  To explore the beliefs and practices of Australian surgeons regarding surgical intervention to release tongue‐tie and to determine the main referral sources. In addition, we aimed to ascertain if there were differences in beliefs and practices according to surgical specialty.Methods:  Four hundred surgeons in three different surgical specialties were surveyed via questionnaire. Multiple choice response questions and open ended questions were used to explore beliefs and practices surrounding tongue‐tie assessment, management and follow up. The questionnaires were distributed by email (where available), followed by fax and mail.Results:  A response rate of 80.8% (n = 323) was obtained. Of these, 236 (73%) reported they practised surgery to release tongue‐tie; 46% were oral and maxillofacial surgeons, 37% were plastic surgeons and 17% were paediatric general surgeons. Indications for surgical management and follow up varied according to surgical specialty. There was no clear consensus regarding clinical indicators for surgery or functional outcomes following surgery.Conclusions:  It appears that until a prospective study designed to address some of the controversial issues outlined is undertaken, we will remain ignorant about the need for surgery to release tongue‐tie in children.
Pneumococcal meningitis in Western Australian children: Epidemiology, microbiology and outcome
Authors: King BA , Richmond P 
Published: October 2004

Objectives:  Pneumococcal meningitis is now vaccine‐preventable but continues to cause high rates of neurological sequelae internationally. Population‐based epidemiology, outcome and microbiology data are necessary to target vaccination strategies. This study outlines these key areas for Western Australian children diagnosed 1990−2000.Methods:  The charts of all rural and metropolitan children with International Classification of Disease 9 and 10 discharge codes of pneumococcal or streptococcal meningitis from the Health Department's Hospital Morbidity Data System were reviewed.Results:  Over 10.5 years, 94 episodes were confirmed. The average annual incidence for children under 2 years was 13.45 per 100 000 and 0.66 per 100 000 for children 2 years or older. Indigenous children had an almost seven‐fold increased risk compared to non‐Indigenous (with 78.55 per 100 000 in the under two‐year Indigenous group). Eight children died and 24 of the survivors had neurological sequelae. Penicillin resistance occurred in four of 87 isolates. One quarter of the cohort qualify under the current Australian policy of vaccination of high‐risk children with seven‐valent conjugate (7vPCV) vaccine. Most isolates (49/58) were 7vPCV serotypes, however, Indigenous populations were less well‐covered (58.3% covered vs 91.3% of isolates from non‐Indigenous children). Indigenous coverage would be improved to 75% with 11‐valent conjugate vaccine.Conclusions:  Indigenous children and those under 2 years are most affected by pneumococcal meningitis and remain primary vaccination targets. Three quarters of these children would not be protected by a policy of vaccination of only high‐risk children with 7vPCV − improved protection requires higher valencies for Indigenous populations and universal infant vaccination.
Pneumococcal meningitis: Clinical course and resource use in Western Australian children
Authors: King BA , Richmond P 
Published: October 2004

Objectives:  Paediatric pneumococcal meningitis causes high rates of neurological sequelae and is presenting challenges due to the emergence of antibiotic resistance. Diagnosis can be difficult and management is frequently complicated and resource intensive. This population‐based study outlines the diagnosis, clinical course and initial resource use of Western Australian (WA) children diagnosed between 1990 and 2000.Methods:  The charts of all rural and metropolitan children discharged from all WA hospitals with International Classification of Disease 9 and 10 codes of pneumococcal or streptococcal meningitis from the Health Department's Hospital Morbidity Data System were reviewed retrospectively.Results:  Ninety‐four episodes of pneumococcal meningitis were confirmed (median age 12.4 months). Initial diagnosis was often difficult with a suggestive prodrome in less than one quarter of cases and a median of two reviews until diagnosis (range 1−7). The median duration of hospitalization was 11.6 days, 41.5% were admitted to the Intensive Care Unit (ICU), and 47.9% had seizures. There were eight related deaths and neurological sequelae occurred in 24. Initial hospitalization cost on average $A19 900. Penicillin resistance was first noted in 1993 and occurred in 4.6% of isolates. Most cases (84.5%) were caused by serotypes contained in the currently available seven‐valent conjugate vaccine.Conclusions:  Pneumococcal meningitis is often difficult to diagnose, necessitates long and frequently complicated in‐patient stays and has high rates of neurological sequelae. It is possible to prevent most cases with new conjugate vaccines.
Head lice prevalence in primary schools in Victoria, Australia
Authors: Counahan M , Andrews R , Büttner P , Byrnes G , Speare R 
Published: October 2004

Objectives:  To determine the prevalence of and assess risk factors associated with head lice infections (pediculosis) in children from government primary schools in Victoria, Australia.Methods:  Between May and October 2001, children were selected by clustered random sampling of schools and classes, then examined for head lice using hair conditioner and a fine‐toothed head lice comb. There were 1838 children screened from 16 primary schools. Risk factors evaluated included metropolitan or rural residence, school class, gender and hair length.Results:  Thirteen percent of children (239/1838) had an active infection (95% CI, 10.9−15.1) and 3.3% (61/1838) had an inactive infection (95% CI, 2.0−4.6). Prevalence of active pediculosis varied between schools from 0 to 28%. Our screening identified no more than one case per class in the majority of classes screened (58.5%). Females were 2.2 times more likely to have active infection than males (95% CI [1.7,2.9]) and there was no significant difference for the other risk factors investigated.Conclusions:  Our study demonstrated the prevalence of head lice varied across Victoria and showed that risk factors commonly attributed to head lice infections did not hold true. Our findings support the premise that traditional ad hoc mass school‐based screening may not be the best use of resources when controlling head lice. We suggest a more pragmatic community‐based approach.