bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aspen wood-wool is preferred as a resting place, but does not affect intracage fighting of male BALB/c and C57BL/6J mice
Authors: Eskola Satu , Kaliste-Korhonen Eila 
Published: April 2007

Aspen wood-wool, provided as nesting material, was evaluated as a possible improvement of cage environment for 10-14-week-old inbred male mice maintained in groups of six (BALB/c n = 72 and C57BL/6J n = 36). The daily behaviour of mice was video recorded and their body weight, food consumption, weights of some organs and serum corticosterone concentrations were measured. Aggressive interactions between cage mates and against a strange intruder as well as the number of wounds on the back of the animals was monitored in order to evaluate the effect of nesting material on intermale aggression. Nesting material did not affect the daily active/passive behaviour patterns of mice, although animals clearly preferred it as a resting place. BALB/c mice given nesting material showed less weight gain and smaller brown adipose tissue weights than animals without nesting material. The other characteristics measured were not affected by the presence of nesting material in either strain. The presence of nesting material had no effect on fighting in cages. C57BL/6J mice were more aggressive than BALB/c mice according to the number of wounded animals in a cage. Wounded BALB/c mice had enlarged spleens and decreased epididymal adipose tissue weights. In conclusion, the nesting material used in this study did not adversely affect the animals. On the other hand, the material was clearly preferred to conventional bedding as a resting place. These findings suggest that nesting material may improve the cage environment of laboratory mice. Furthermore, there was an indication of strain differences in aggressive behaviour. It could be suggested that C57BL/6J mice are less tolerant towards intruders and housing six mice per cage is not suitable for this strain.
Methods for exposure of laboratory animals to ultraviolet radiation
Authors: Goettsch Wim , Garssen Johan , de Gruijl Frank R. , Dortant Paul , van Loveren Henk 
Published: April 2007

Two different sources of ultraviolet B (UVB) radiation, an electronically controlled UVB exposure unit, containing FS40 tubes, and a hand-held Kromayer lamp, were evaluated for actual irradiance in W/m2 and spectra (physical dosimetry and biological dosimetry (skin effects in rodents)). The technical studies of the FS40 sources demonstrated that the flux intensity of the lamps could be changed electronically, without affecting the spectrum. Thus it was possible to standardize UVB exposure electronically. The biologically effective doses of these sources were analysed in RIV-Tox Wistar rats and BALB/c mice. After low doses of UVB radiation, histopathological changes such as acanthosis, hyperkeratosis and dermal inflammation were observed in the skin without the presence of major side effects such as erythema and oedema. After higher doses of UVB radiation erythema and oedema were clearly visible. Quantitative studies showed that the minimal erythema dose, as a biological parameter, correlated well to the emission in J/m2. In addition, biological parameters such as acanthosis and inflammation in the skin correlated well to the actual exposure in J/m2 and were sensitive biomarkers for UVB-induced skin toxicity. Thus, in addition to minimal erythemal doses, acanthosis and inflammation may also be applied as biologically relevant doses for studies of the biological effects of UVB radiation.
EEG evaluation of reflex testing as assessment of depth of pentobarbital anaesthesia in the rat
Authors: Haberham Z. L. , van den Brom W. E. , Venker-van Haagen A. J. , Baumans V. , de Groot H. N. M. , Hellebrekers L. J. 
Published: April 2007

Electroencephalography (EEG) was applied to evaluate the validity of the paw pinch reflex as an indicator of anaesthetic depth in rats which are anaesthetized with a single intraperitoneal dose of pentobarbital. After induction of the anaesthesia, characterized by the rapid loss of the animals' ability to maintain upright posture, the EEG of 10 out of 11 rats was dominated by paroxysmal (burst suppression) activity, associated with unconsciousness. In seven out of 11 rats, the paw pinch reflex was lost after onset of paroxysmal electroencephalographic activity. However, the paw pinch reflex remained present in four out of 11 animals, demonstrating that the response is independent of cortical activity. In five out of seven rats, the EEG still showed paroxysmal activity when the paw pinch reflex was regained. However, in two other rats the EEG returned to a pattern similar to that shown by awake animals, 4 and 21 min respectively, before the reflex was regained. These data indicate that in the pentobarbital-anaesthetized rat, presence of the paw pinch reflex is not related to the level of depression of electrical activity in the cerebral cortex, and consequently is probably not related to the level of consciousness. Based upon these findings it is concluded that the paw pinch reflex is unreliable as a sole indicator of anaesthetic depth.
Antidepressants and suicidality
Authors: Lader Malcolm 
Published: April 2007

The acceptability of antidepressants among both professionals and the lay public, including depressed patients, has been set back by insistent reports of an enhanced suicidal risk. This encompasses suicidal ideas, intention, attempts and completed acts. Such behaviour is an intrinsic feature of the more depressed individuals and it is difficult to disentangle the risks (or protection) afforded by the use of antidepressants from the background risk. Clinical trials contain too little data even on meta-analysis to allow firm conclusions, especially with respect to suicide itself. At the other end of the continuum, correlation of prescribing data and suicide data suggests a protective effect of antidepressants, especially the selective serotonin reuptake inhibitors (SSRIs). Other GP databases suggest that a major effect on completed suicide can be ruled out, but that suicidal attempts may be somewhat more frequent in patients taking antidepressants. Against this, other causes of mortality in depressed patients are markedly lower in SSRI-taking patients. An exception is venlafaxine which may be associated with a discernibly enhanced risk, but differential allocation to groups cannot be excluded. The efficacy of antidepressants in children and adolescents is weaker than in adults, and only significant for fluoxetine. The risks of suicidal behaviour may be increased in this age group; careful choice of medication and close monitoring are essential. In adults, the suicidal risk should be carefully assessed and patients managed accordingly. They and their carers should be warned of a possible delay in onset of effect. 'Ex-label' use is especially problematic. All in all, the antidepressants have a favourable risk/benefit ratio, but special cases such as children necessitate thoughtful prescribing.
The accuracy of image-free computer navigation in the placement of the femoral component of the Birmingham Hip Resurfacing
Authors: Davis E. T. , Gallie P. , Macgroarty K. , Waddell J. P. , Schemitsch E. 
Published: April 2007

A cadaver study using six pairs of lower limbs was conducted to investigate the accuracy of computer navigation and standard instrumentation for the placement of the Birmingham Hip Resurfacing femoral component. The aim was to place all the femoral components with a stem-shaft angle of 135°. The mean stem-shaft angle obtained in the standard instrumentation group was 127.7° (120° to 132°), compared with 133.3° (131° to 139°) in the computer navigation group (p = 0.03). The scatter obtained with computer-assisted navigation was approximately half that found using the conventional jig. Computer navigation was more accurate and more consistent in its placement of the femoral component than standard instrumentation. We suggest that image-free computer-assisted navigation may have an application in aligning the femoral component during hip resurfacing.
The initial stability and contact mechanics of a press-fit resurfacing arthroplasty of the hip
Authors: Udofia I. , Liu F. , Jin Z. , Roberts P. , Grigoris P. 
Published: April 2007

Finite element analysis was used to examine the initial stability after hip resurfacing and the effect of the procedure on the contact mechanics at the articulating surfaces. Models were created with the components positioned anatomically and loaded physiologically through major muscle forces. Total micromovement of less than 10 μm was predicted for the press-fit acetabular components models, much below the 50 μm limit required to encourage osseointegration. Relatively high compressive acetabular and contact stresses were observed in these models. The press-fit procedure showed a moderate influence on the contact mechanics at the bearing surfaces, but produced marked deformation of the acetabular components. No edge contact was predicted for the acetabular components studied. It is concluded that the frictional compressive stresses generated by the 1 mm to 2 mm interference-fit acetabular components, together with the minimal micromovement, would provide adequate stability for the implant, at least in the immediate post-operative situation.
Balloon kyphoplasty as a single or as an adjunct procedure for the management of symptomatic vertebral haemangiomas
Authors: Hadjipavlou A. , Tosounidis T. , Gaitanis I. , Kakavelakis K. , Katonis P. 
Published: April 2007

Vertebral haemangiomas are usually asymptomatic and discovered fortuitously during imaging. A small proportion may develop variable degrees of pain and neurological deficit. We prospectively studied six patients who underwent eight surgical procedures on 11 vertebral bodies. There were 11 balloon kyphoplasties, six lumbar and five thoracic. The mean follow-up was 22.3 months (12 to 36). The indications for operation were pain in four patients, severe back pain with Frankel grade C paraplegia from cord compression caused by soft-tissue extension from a thoracic vertebral haemangioma in one patient, and acute bleeding causing Frankel grade B paraplegia from an asymptomatic vascular haemangioma in one patient. In four patients the exhibited aggressive vascular features, and two showed lipomatous, non-aggressive, characteristics. One patient who underwent a unilateral balloon kyphoplasty developed a recurrence of symptoms from the non-treated side of the vertebral body which was managed by a further similar procedure. Balloon kyphoplasty was carried out successfully and safely in all patients; four became asymptomatic and two showed considerable improvement. Neurological recovery occurred in all cases but bleeding was greater than normal. To avoid recurrence, complete obliteration of the lesion with bone cement is indicated. For acute bleeding balloon kyphoplasty should be combined with emergency decompressive laminectomy. For intraspinal extension with serious neurological deficit, a combination of balloon kyphoplasty with intralesional alcohol injection is effective.
Endoprosthetic replacement of the distal femur for bone tumours
Authors: Myers G. J. C. , Abudu A. T. , Carter S. R. , Tillman R. M. , Grimer R. J. 
Published: April 2007

We investigated whether improvements in design have altered the outcome for patients undergoing endoprosthetic replacement of the distal femur after resection of a tumour. Survival of the implant and ‘servicing’ procedures have been documented using a prospective database, review of the design of the implant and case records. In total, 335 patients underwent a distal femoral replacement, 162 having a fixed-hinge design and 173 a rotating-hinge. The median age of the patients was 24 years (interquartile range 17 to 48). A total of 192 patients remained alive with a mean follow-up of 12 years (5 to 30). The risk of revision for any reason was 17% at five years, 33% at ten years and 58% at 20 years. Aseptic loosening was the main reason for revision of the fixed-hinge knees while infection and fracture of the stem were the most common for the rotating-hinge implant. The risk of revision for aseptic loosening was 35% at ten years with the fixed-hinge knee, which has, however, been replaced by the rotating-hinge knee with a hydroxyapatite collar. The overall risk of revision for any reason fell by 52% when the rotating-hinge implant was used. Improvements in the design of distal femoral endoprostheses have significantly decreased the need for revision operations, but infection remains a serious problem. We believe that a cemented, rotating-hinge prosthesis with a hydroxyapatite collar offers the best chance of long-term survival of the prosthesis.
Aptamers Evolved from Cultured Cancer Cells Reveal Molecular Differences of Cancer Cells in Patient Samples
Authors: Shangguan Dihua , Cao Zehui Charles , Li Ying , Tan Weihong 
Published: April 2007

Abstract
Background: Molecular-level differentiation of neoplastic cells is essential for accurate and early diagnosis, but effective molecular probes for molecular analysis and profiling of neoplastic cells are not yet available. We recently developed a cell-based SELEX (systematic evolution of ligands by exponential enrichment) strategy to generate aptamers (designer DNA/RNA probes) as molecular probes to recognize neoplastic cells.
Methods: We tested 6 cell-SELEX–generated aptamers with equilibrium dissociation constants in the nanomolar to subnanomolar range: sgd5, selected from Toledo cells, a human diffuse large-cell lymphoma cell line (B-cell), and sgc8, sgc3, sgc4, sgd2, and sgd3 from CCRF-CEM cells, a human precursor T cell acute lymphoblastic leukemia (T-ALL) cell line. Aptamers were labeled with fluorescein isothiocyanate fluorophores and then used to recognize, by flow cytometric analysis, neoplastic cells in cultured hematopoietic cell lines and clinical samples.
Results: Aptamer sgd5 recognized only its target cells. Aptamers sgc3, sgd2, sgd3, sgc4, and sgc8, selected from a T-cell leukemia cell line, identified all of the cultured T-cell leukemia cell lines with relatively high fluorescence intensity. Aptamers sgc8, sgc3, and sgd3 showed good selectivity toward T-ALL cells and almost no binding to normal hematopoietic cells or lymphoma and myeloma cells. Selected aptamers also detected targets on the cell membranes of neoplastic cells in patient samples.
Conclusions: Aptamers selected against cultured neoplastic cells can effectively be used as molecular probes for recognition of neoplastic cells in patient samples. Cell-based aptamer selection can be used to generate aptamer probes to obtain molecular signatures of neoplastic cells in patient samples.
Comparison of Bromcresol Green and Agarose Protein Electrophoresis for Quantitation of Serum Albumin in Multiple Myeloma
Authors: Snozek Christine LH , Saenger Amy K , Greipp Philip R , Bryant Sandra C , Kyle Robert A , Rajkumar S Vincent , Katzmann Jerry A 
Published: April 2007

Abstract
Background: The International Staging System for multiple myeloma has increased the importance of accurate measurement of serum albumin. Two common albumin assays, bromcresol green (BCG) and agarose gel protein electrophoresis (PEL), frequently yield discordant results, creating confusion regarding which assay is superior for use in myeloma.
Methods: We measured albumin by BCG on a Roche Modular system, by PEL with a Helena SPIFE SPE Vis agarose gel, and by immunonephelometry performed on a Dade Behring BNII nephelometer. BCG and PEL were used to measure albumin in 5777 patient samples, and all 3 methods were used in an additional 252 samples. The clinical impact was assessed on 698 myeloma patient samples.
Results: For sera with zero/low monoclonal immunoglobulin protein (M)-spike (0 to &lt;15 g/L), results for both BCG and PEL correlated well to nephelometry, although median PEL results were 8 g/L lower than corresponding BCG measurements. Correlation between PEL and nephelometry or BCG diminished with increasing M-spike, with PEL eventually overestimating albumin compared with both other assays. IgG and IgA M-spikes showed significantly different effects on albumin discordance. For 35% of myeloma patients, discrepancy between BCG and PEL had a potentially clinically significant effect on staging, but no difference in group survival was found.
Conclusions: Both BCG and PEL correlate well to nephelometry in sera with zero/low M-spikes. In the presence of larger M-spikes, PEL correlates poorly to nephelometry or BCG, whereas BCG compares well with nephelometry regardless of M-spike. Thus, albumin measurement can be performed reliably in myeloma patient sera by use of inexpensive, automated BCG assays.
Genotype–Environment Interactions: Cognitive Aging and Social Factors
Authors: Reynolds Chandra A. , Gatz Margaret , Berg Stig , Pedersen Nancy L. 
Published: April 2007

AbstractThe possibility of genotype–environment interaction for memory performance and change was examined in 150 monozygotic (MZ) twin pairs from the Swedish Adoption Twin Study of Aging (SATSA). We used an MZ twin pair difference approach to examine the possibility that genotype was associated with intrapair variability and thus suggestive of genotype–nonshared environment interactions. Multiple ‘variability genes’ were found for longitudinal change in a semantic memory task including candidates coding for apolipoprotein E (APOE) and estrogen receptor alpha (ESR1) as well as serotonin candidates (HTR2Aand5HTT). One candidate also related to variability in change in episodic memory (5HTT). Of the significant associations observed, generally results indicated that MZ pairs who carry putative risk alleles were less variable than noncarriers, suggesting that noncarriers may be more sensitive to environmental contexts. We sought to ‘contextualize’ the possible nonshared environmental influences for found gene–environment (G × E) effects by considering intrapair differences in measured social and stress factors, including social support, life events and depressive symptoms. Results suggested that nonshared environmental influences associated with depressive symptoms may moderate the G × E relationship observed forESR1andAPOEand longitudinal semantic memory change whereby noncarriers of putative risk alleles may be relatively more sensitive to depressionevoking environmental contexts than carriers of the risk allele. Thus, the contexts that facilitate or reduce depressive symptoms may affect semantic memory resiliency dependent on genotype. Further work ought to consider larger sample sizes as well as consider additional social and contextual factors.
Genetic Contribution to the P3 in Young and Middle-Aged Adults
Authors: Smit Dirk J. A. , Posthuma Danielle , Boomsma Dorret I. , de Geus Eco J.C. 
Published: April 2007

AbstractPrevious studies in young and adolescent twins suggested substantial genetic contributions to the amplitude and latency of the P3 evoked by targets in an oddball paradigm. Here we examined whether these findings can be generalized to adult samples. A total of 651 twins and siblings from 292 families participated in a visual oddball task. In half of the subjects the age centered around 26 (young adult cohort), in the other half the age centered around 49 (middle-aged adult cohort). P3 peak amplitude and latency were scored for 3 midline leads Pz, Cz, and Fz. No cohort differences in heritability were found. P3 amplitude (∼50%) and latency (∼45%) were moderately heritable for the 3 leads. A single genetic factor influenced latency at all electrodes, suggesting a single P3 timing mechanism. Specific genetic factors influenced amplitude at each lead, suggesting local modulation of the P3 once triggered. Genetic analysis of the full event-related potential waveform showed that P3 heritability barely changes from about 100 ms before to 100 ms after the peak. Age differences are restricted to differences in means and variances, but the proportion of genetic variance as part of the total variance of midline P3 amplitude and latency does not change from young to middle-aged adulthood.
Personality, Health and Lifestyle in a Questionnaire Family Study: A Comparison Between Highly Cooperative and Less Cooperative Families
Authors: Distel Marijn A. , Ligthart Lannie , Willemsen Gonneke , Nyholt Dale R. , Trull Timothy J. , Boomsma Dorret I. 
Published: April 2007

AbstractThe effect of nonresponse on health and lifestyle measures has received extensive study, showing at most relatively modest effects. Nonresponse bias with respect to personality has been less thoroughly investigated. The present study uses data from responding individuals as a proxy for the missing data of their nonresponding family members to examine the presence of nonresponse bias for personality traits and disorders as well as health and lifestyle traits. We looked at the Big Five personality traits, borderline personality disorder (BPD) features, attention-deficit/hyperactivity disorder, Anger, and several measures of health (Body Mass Index, migraine) and lifestyle (smoking, alcohol use). In general, outcomes tend to be slightly more favorable for individuals from highly cooperative families compared to individuals from less cooperative families. The only significant difference was found for BPD features (p = .001). However, the absolute difference in mean scores is very small, less than 1 point for a scale ranging from 0 to 72. In conclusion, survey data on personality, health and lifestyle are relatively unbiased with respect to nonresponse.
Multiple Maternities and Neighborhood Income
Authors: Urquia Marcelo Luis , Frank John William , Glazier Richard Henry , Moineddin Rahim 
Published: April 2007

AbstractThis study aimed to examine differences in multiple maternities by neighborhood-income levels in Toronto, Canada. Hospital records were used to perform secondary analysis of 144,731 maternities resulting in single or multiple infants live-born to mothers residing in the City of Toronto 1996 to 2001. The independent variable was neighborhood income, defined as mean household neighborhoodincome quintiles. Multiple logistic regression analysis was used to compute adjusted odds ratios (AORs) and 95% confidence intervals (CIs). Differences by income levels were found in twin maternities but not in higher order maternities. Twin maternities were more likely to occur in the richest neighborhood-income quintile compared to the rest of the population (AOR: 1.25, 95% CI: 1.10-1.41), after adjustment for potential confounders. The positive association between high neighborhood income and twin maternities found in this study suggests that the richest neighborhoods select families whose characteristics pose them at increased risk of having twins. Further studies are needed to clarify the underlying mechanisms leading to socioeconomic differences in multiple births.
Determination of residual stress in bonded wood components
Authors: Scheffler Michael , Weber Tony , Niemz Peter , Hardtke Hans-Jürgen 
Published: April 2007

Abstract
Climate tests on double-layered samples were performed to detect deformation and induced stress concentrations. The paper is divided into two parts. The first presents experimental results for double-layered specimens. These specimens consisted of two wooden layers (each conditioned at a different climate before bonding) that were bonded using two different adhesives. The displacement field of the specimens was measured by means of digital fringe projection. The second part presents finite element results for two model stages using coupled thermal-mechanical analysis. For the first simple model, both orthotropic properties and the grain orientations were taken into account to investigate the behavior of the layers in principle. The results were compared to those for the experimental set-up. The improved second-stage model considers the adhesive layer between the wooden layers. The experimental and computational results of the improved simulation model are in good agreement. In the future, if inelastic material behavior is considered in a competitively superior manner, even better simulation results can be expected.