bluuebunny/crossref_metadata_2025_split huggingface dataset:
Follow‐Up After Surgery for Benign Nodular Thyroid Disease: Evidence‐Based Approach
Authors: Phitayakorn Roy , McHenry Christopher R. 
Published: March 2008

AbstractBackgroundThere is no consensus on what constitutes appropriate methodology and timing for follow‐up of patients after surgery for benign nodular disease.MethodsA systematic review of the medical literature using evidence‐based criteria was used to address the following four issues: (1) How often should patients who have undergone thyroidectomy for the treatment of benign nodular goiter be followed, and what constitutes appropriate follow‐up? (2) What is the most appropriate method for detecting recurrent nodular thyroid disease? (3) Does thyroid hormone administration prevent recurrent nodular thyroid disease? (4) Does iodine administration prevent recurrent nodular thyroid disease?ResultsAltogether, 742 articles were found in MEDLINE using a keyword search strategy; we then narrowed them to 23 articles. There were a total of four articles with Level I data, five articles with Level II data, one article with Level III data, and 13 articles with Level IV or retrospective data.ConclusionsBased on the available data, it is our recommendation that patients undergoing thyroid lobectomy for benign nodular thyroid disease should be followed with an annual physical examination, neck ultrasonography, and serum thyroid‐stimulating hormone (TSH) measurement. Patients undergoing total thyroidectomy should be followed with an annual physical examination and a serum TSH measurement. Routine thyroxine and/or iodine supplementation may be useful for preventing recurrence in patients from iodine‐deficient regions.
Size-dependent Fano Interaction in the Laser-etched Silicon Nanostructures
Authors: Kumar Rajesh , Shukla AK , Mavi HS , Vankar VD 
Published: March 2008

Abstract
Photo-excitation and size-dependent Raman scattering studies on the silicon (Si) nanostructures (NSs) prepared by laser-induced etching are presented here. Asymmetric and red-shifted Raman line-shapes are observed due to photo-excited Fano interaction in the quantum confined nanoparticles. The Fano interaction is observed between photo-excited electronic transitions and discrete phonons in Si NSs. Photo-excited Fano studies on different Si NSs show that the Fano interaction is high for smaller size of Si NSs. Higher Fano interaction for smaller Si NSs is attributed to the enhanced interference between photo-excited electronic Raman scattering and phonon Raman scattering.
In vitro characterization of a murine oligodendrocyte precursor cell line (BO‐1) following spontaneous immortalization
Authors: Pringproa Kidsadagon , Kumnok Jirawat , Ulrich Reiner , Baumgärtner Wolfgang , Wewetzer Konstantin 
Published: March 2008

AbstractThe understanding of oligodendrocyte differentiation is crucial for designing therapies of demyelinating diseases. Oligodendrocyte precursor cells are of particular interest in this context, because of their remyelinating potential. Permanent cell lines, which are a versatile tool for studying oligodendrocyte physiology, have been so far mainly established from the rat CNS. In the present study, we describe a novel murine oligodendrocyte precursor cell line (BO‐1) established by spontaneous immortalization using light microscopy, immunocytochemical phenotyping and genetic analysis. BO‐1 cells displayed a bi‐ to multipolar morphology and expressed early oligodendrocytic lineage markers, such as A2B5 and NG‐2. Expression of pre‐oligodendrocyte (O4, CNPase) and mature oligodendrocyte markers (e.g. myelin basic protein) was found in about 30% and 1.5% of the cells, respectively. Addition of serum, known to promote type‐2 astrocyte differentiation, significantly increased the number of GFAP‐positive cells, while thyroid hormones, (T3/T4) known to foster oligodendrocyte differentiation, did not substantially alter the antigenic and gene expression of myelin markers. This deficiency might be related to the high intrinsic proliferation rate of BO‐1 cells that was unaltered upon removal of mitogenic factors. Expression of O4 and CNPase in BO‐1 cells could be significantly increased by co‐culture with primary astrocytes suggesting that the differentiating potential of BO‐1 cells was influenced by environmental factors and may have to be fully explored in future studies. In summary, the novel murine BO‐1 cell line shares several characteristics with oligodendrocyte precursor cells but displays a restricted differentiation into mature oligodendrocytes.
Mechanical abrasion of kimberlite indicator minerals: experimental investigations
Authors: Afanas’ev V.P. , Nikolenko E.I. , Tychkov N.S. , Titov A.T. , Tolstov A.V. , Kornilova V.P. , Sobolev N.V. 
Published: March 2008

Abstract
The relative abrasive stability of kimberlite indicator minerals such as pyrope, picroilmenite, olivine, and apatite as well as diamonds and kimberlite fragments was studied experimentally, and the following sequence of mineral abrasive stability was established: pyrope–olivine–picroilmenite–apatite–kimberlite fragments. Diamond did not virtually change during the experiment. Kimberlite fragments appeared to be rather stable. Their relics were preserved until the end of the experiment, whereas the other minerals acquired wearing-resistant shapes. Pyrope, olivine, and apatite were shaped into an oval. Owing to anisotropy of microhardness, picroilmenite forms hexagonal tablets, which are typical of ancient haloes of indicator minerals in all diamondiferous regions. The parity analysis of the abrasive stabilities of pyrope and picroilmenite has shown that in the haloes of “mature” littoral zone represented by pyrope alone, with a possible admixture of diamond, picroilmenite is completely destroyed by abrasion.
Variation in longevity and traits of leaves among co-occurring understorey plants in a tropical montane forest
Authors: Shiodera Satomi , Rahajoe Joeni S. , Kohyama Takashi 
Published: March 2008

Abstract:The relationship between leaf longevity and other leaf traits was compared among different life-form categories (trees, herbs, climbers and epiphytes) of 101 plant species in a tropical montane forest on Mt. Halimun, West Java, Indonesia. We applied the Cox proportional hazards regression to estimate the leaf longevity of each species from 30 mo of census data. We examined whether estimated longevity was explained by either species life-form categories, taxonomic groupings (eudicots, monocots, magnoliids and chloranthales, and ferns) or such leaf traits as leaf area, leaf mass per area (LMA), mass-based leaf nitrogen, penetrometer reading, condensed-tannin-free total phenolics and condensed tannin. There was a wide-ranged interspecific variation in leaf longevity, mostly 10–50 mo, similarly across life-form categories. LMA showed a strong positive influence on leaf longevity. We found that relationships between leaf longevity and some leaf traits were different among various life forms. Trees tended to have high LMA, while climbers tended to have low LMA at the same leaf longevity. We hypothesize that such difference among life forms reflects shoot architecture characteristics. Multi-shoot trees with branching architecture need to have self-supporting leaves, whereas semi-epiphytic climbers can maintain relatively low biomass investment to leaves hanging or relying upon the mechanical support from host plants.
Patterns of community composition in two tropical tree frog assemblages: separating spatial structure and environmental effects in disturbed and undisturbed forests
Authors: Ernst Raffael , Rödel Mark-Oliver 
Published: March 2008

Abstract:An on-going controversy in community ecology involves the debate about the many factors that affect the assembly and composition of a given species assemblage. Theory suggests that community composition is influenced by environmental gradients or biotic processes. This study examines patterns of community composition in two tropical tree frog assemblages of primary and exploited lowland rain-forest sites in the Guiana Shield area of central Guyana, South America and the Upper Guinean rain-forest block of south-western Côte d'Ivoire, West Africa. We tested community composition and species abundance data of two adult tree frog communities collected on 21 standardized transects during a period of 5 y for evidence of spatial correlation in community composition. We applied simple and partial Mantel tests to separate the effects of environmental variables, spatial distance and spatial autocorrelation on community composition. Whenever environmental effects were accounted for, we found significant positive spatial correlation of community composition. All assemblages appeared to be spatially structured, i.e. sites in close proximity had similar species assemblages. However, spatially structured environmental variation (autocorrelation) did not account for the spatial structure of species incidence. Environmental factors did not prove to be significant predictors of species incidence in any of the assemblages analysed, even if we controlled for spatial effects. Observed correlation patterns of species composition were consistent within respective realms and disturbance regimes. Moreover, general correlation patterns were consistent between geographic regions. These results are in contrast to previously published results from a study on leaf-litter anurans and indicate that group-specific differences must not be neglected when analysing patterns of species composition in anurans as they may drastically alter the outcome of the analysis.
Rooting depth and above-ground community composition in Kalahari sand woodlands in western Zimbabwe
Authors: Holdo Ricardo M. , Timberlake Jonathan 
Published: March 2008

Abstract:The pattern of coarse-root distribution was analysed in the woody plant community along a 200-m edaphic gradient on a Kalahari sand woodland catena in Zimbabwe. The root systems of 45 trees and shrubs were excavated, mapped, and digitized to analyse rooting depth and architecture. Patterns of change in the above-ground community were also identified along this transect. Rooting depth increased, and the centre of mass of the root profile shifted towards the maximum rooting depth as a function of distance up the catena. The data also suggest that interspecific variation in rooting depth may increase up the catena. The below-ground pattern was accompanied by above-ground changes: species richness and basal area also increased up the catena. It is hypothesized that increasing soil depth allows greater coexistence of alternative water-use strategies, resulting in the observed increase in species richness up the catena.
Temporal and spatial variation of fine roots in a northern AustralianEucalyptus tetrodontasavanna
Authors: Janos David P. , Scott John , Bowman David M. J. S. 
Published: March 2008

Abstract:Six rhizotrons in anEucalyptus tetrodontasavanna revealed seasonal changes in the abundance of fine roots (≤ 5 mm diameter). Fine roots were almost completely absent from the upper 1 m of soil during the dry season, but proliferated after the onset of wet-season rains. At peak abundance of 3.9 kg m−2soil surface, fine roots were distributed relatively uniformly throughout 1 m depth, in contrast with many tropical savannas and tropical dry forests in which fine roots are most abundant near the soil surface. After 98% of cumulative annual rainfall had been received, fine roots began to disappear rapidly, such that 76 d later, less than 5.8% of peak abundance remained. The scarcity of fine roots in the upper 1 m of soil early in the dry season suggests that evergreen trees may be able to extract water from below 1 m throughout the dry season. Persistent deep roots together with abundant fine roots in the upper 1 m of soil during the wet season constitute a ‘dual’ root system. Deep roots might buffer atmospheric CO2against increase by sequestering carbon at depth in the soil.
Phase Contrast X-Ray Synchrotron Imaging: Opening Access to Fossil Inclusions in Opaque Amber
Authors: Lak Malvina , Néraudeau Didier , Nel André , Cloetens Peter , Perrichot Vincent , Tafforeau Paul 
Published: March 2008

AbstractA significant portion of Mesozoic amber is fully opaque. Biological inclusions in such amber are invisible even after polishing, leading to potential bias in paleoecological and phylogenetic studies. Until now, studies using conventional X-ray microtomography focused on translucent or semi-opaque amber. In these cases, organisms of interest were visualized prior to X-ray analyses. It was recently demonstrated that propagation phase contrast X-ray synchrotron imaging techniques are powerful tools to access invisible inclusions in fully opaque amber. Here we describe an optimized synchrotron microradiographic protocol that allowed us to investigate efficiently and rapidly large amounts of opaque amber pieces from Charentes (southwestern France). Amber pieces were imaged with microradiography after immersion in water, which optimizes the visibility of inclusions. Determination is not accurate enough to allow precise phylogenetic studies, but provides preliminary data on biodiversity and ecotypes distribution; phase contrast microtomography remains necessary for precise determination. Because the organisms are generally much smaller than the amber pieces, we optimized local microtomography by using a continuous acquisition mode (sample moving during projection integration). As tomographic investigation of all inclusions is not practical, we suggest the use of a synchrotron for a microradiographic survey of opaque amber, coupled with microtomographic investigations of the most valuable organisms.
Light-Emitting Diodes Are Better Illumination Sources for Biological Microscopy than Conventional Sources
Authors: Cole Richard W. , Turner James N. 
Published: March 2008

AbstractLight-emitting diodes (LEDs) can be easily and inexpensively integrated into modern light microscopes. There are numerous advantages of LEDs as illumination sources; most notably, they provide brightness and spectral control. We demonstrate that for transmitted light imaging, an LED can replace the traditional tungsten filament bulb while offering longer life; no color temperature change with intensity change; reduced emission in the infrared region, which is important for live cell imaging; and reduced cost of ownership. We show a direct substitution of the typical tungsten bulb with a commercially available LED and demonstrated the color stability by imaging a histology section over a wide range of light intensities. For fluorescent imaging, where the typical illumination sources are mercury or xenon lamps, we demonstrate that LEDs offer advantages of providing a longer lifespan, having a more constant intensity output over time, more homogeneous illumination, and significantly lower photon dose. Our LED equipped system was used to image and deconvolve dual fluorescently labeled cells, as well as image cells undergoing mitosis expressing green fluorescent protein–histone 2B complex. The timing of the stages of mitosis is well established as an indicator of cell viability.
The phytocannabinoid Δ9‐tetrahydrocannabivarin modulates inhibitory neurotransmission in the cerebellum
Authors: Ma Y‐L , Weston S E , Whalley B J , Stephens G J 
Published: March 2008

Background and purpose:The phytocannabinoid Δ9‐tetrahydrocannabivarin (Δ9‐THCV) has been reported to exhibit a diverse pharmacology; here, we investigate functional effects of Δ9‐THCV, extracted fromCannabis sativa, using electrophysiological techniques to define its mechanism of action in the CNS.Experimental approach:Effects of Δ9‐THCV and synthetic cannabinoid agents on inhibitory neurotransmission at interneurone‐Purkinje cell (IN‐PC) synapses were correlated with effects on spontaneous PC output using single‐cell and multi‐electrode array (MEA) electrophysiological recordings respectively, in mouse cerebellar brain slicesin vitro.Key results:The cannabinoid receptor agonist WIN 55,212‐2 (WIN55) decreased miniature inhibitory postsynaptic current (mIPSC) frequency at IN‐PC synapses. WIN55‐induced inhibition was reversed by Δ9‐THCV, and also by the CB1receptor antagonist AM251; Δ9‐THCV or AM251 acted to increase mIPSC frequency beyond basal values. When applied alone, Δ9‐THCV, AM251 or rimonabant increased mIPSC frequency. Pre‐incubation with Δ9‐THCV blocked WIN55‐induced inhibition. In MEA recordings, WIN55 increased PC spike firing rate; Δ9‐THCV and AM251 acted in the opposite direction to decrease spike firing. The effects of Δ9‐THCV and WIN55 were attenuated by the GABAAreceptor antagonist bicuculline methiodide.Conclusions and implications:We show for the first time that Δ9‐THCV acts as a functional CB1receptor antagonist in the CNS to modulate inhibitory neurotransmission at IN‐PC synapses and spontaneous PC output. Δ9‐THCV‐ and AM251‐induced increases in mIPSC frequency beyond basal levels were consistent with basal CB1receptor activity. WIN55‐induced increases in PC spike firing rate were consistent with synaptic disinhibition; whilst Δ9‐THCV‐ and AM251‐induced decreases in spike firing suggest a mechanism of PC inhibition.
Prospective study to assess risk factors for pelvic floor dysfunction after delivery
Authors: SERATI MAURIZIO , SALVATORE STEFANO , KHULLAR VIK , UCCELLA STEFANO , BERTELLI EVELINA , GHEZZI FABIO , BOLIS PIERFRANCESCO 
Published: February 2008

AbstractBackground. To identify obstetric risk factors for de novo pelvic floor disorders after vaginal delivery. Methods. Antenatally asymptomatic women who delivered vaginally were interviewed on urinary, anal and sexual disorders antenatally, 6 and 12 months postpartum. Results. Of 967 women, 336 were included for final analysis. Urinary symptoms occurred in 27 and 23% of women at 6 and 12 months postpartum: univariate analysis showed a significant relation to the use of epidural analgesia (p =0.04) and to a second stage of labour >1 h (p =0.02), the latter was confirmed significant by multivariate analysis. Anal incontinence occurred in 7.1 and 6.8% of women at 6 and 12 months postpartum, respectively. Dyspareunia was reported by 24% at 6 months, decreasing to 8% at 12 months (p <0.0001). Conclusions. Our study shows that a second stage longer than 1 h is associated with the development of postpartum urinary incontinence. Except for dyspareunia, pelvic floor dysfunction rarely resolves spontaneously.
Prevalence of maternal group B streptococcal colonisation in European countries
Authors: BARCAITE EGLE , BARTUSEVICIUS ARNOLDAS , TAMELIENE RASA , KLIUCINSKAS MINDAUGAS , MALECKIENE LAIMA , NADISAUSKIENE RUTA 
Published: February 2008

AbstractBackground. Group B streptococcus (GBS) is a leading cause of neonatal sepsis in many industrialised countries. However, the burden of perinatal GBS disease varies between these countries. We undertook a systematic review to determine the prevalence of maternal group B streptococcal colonisation, one of the most important risk factor for early onset neonatal infection, and to examine the serotype distribution of the GBS strains isolated and their susceptibility to antibiotics in European countries. Methods. We followed the standard methodology for systematic reviews. We prepared a protocol and a form for data extraction that identifies key characteristics on study and reporting quality. The search was conducted for the years 1996–2006 including electronic, hand searching and screening of reference lists. Results. Twenty‐one studies presented data on 24,093 women from 13 countries. Among all studies, GBS vaginal colonisation rates ranged from 6.5 to 36%, with one‐third of studies reporting rates of 20% or greater. The regional carriage rates were as follows: Eastern Europe 19.7–29.3%, Western Europe 11–21%, Scandinavia 24.3–36%, and Southern Europe 6.5–32%. GBS serotypes III, II and Ia were the most frequently identified serotypes. None of the GBS isolates were resistant to penicillin or ampicillin, whereas 3.8–21.2% showed resistance to erythromycin and 2.7–20% showed resistance to clindamycin. Conclusion. Although there is variation in the proportion of women colonised with GBS, the range of colonisation, the serotype distribution and antimicrobial susceptibility reported from European countries appears to be similar to that identified in overseas countries.
Symptoms of Influenza Virus Infection in Hospitalized Patients
Authors: van den Dool C. , Hak E. , Wallinga J. , van Loon A. M. , Lammers J. W. J. , Bonten M. J. M. 
Published: February 2008

Background.During influenza outbreaks, fever and cough are the most accurate symptoms in predicting influenza virus infection in the community.Objective.To determine the usefulness of fever, cough, and other symptoms for diagnosing influenza virus infection in hospitalized patients.Design.Prospective cohort study.Setting.Three wards (pulmonology, internal medicine and infectious diseases, and geriatrics) of a tertiary care hospital in the Netherlands.Patients.All patients staying in the wards during peak national influenza activity in the 2005-2006 and 2006-2007 influenza seasons.Methods.During peak influenza activity, the presence of fever, cough, and/or other symptoms possibly associated with influenza was monitored for all patients, and nose and throat swab samples were taken twice weekly for virologic analysis.Results.Of 264 patients, 23 (9%) tested positive for influenza virus. The positive predictive value of fever and cough for the diagnosis of influenza virus infection was 23% (95% confidence interval, 0%-62%), and the sensitivity was 35% (95% confidence interval, 11%-58%). The combination of symptoms with the highest positive predictive value (40%) was that of cough, chills, and obstructed nose or coryza. The combination of cough and chills or fever had the highest sensitivity (60%). None of the combinations of symptoms had both a positive predictive value and a sensitivity higher than 40%.Conclusions.Both the sensitivity and the positive predictive value of fever, cough, and/or other symptoms for the diagnosis of influenza virus infection in hospitalized patients are low. The use of these common symptoms for treatment decisions and infection control management will probably be insufficient to contain a nosocomial outbreak, because many influenza cases will remain unidentified.
The effect of sequence quality on sequence alignment
Authors: Malde Ketil 
Published: February 2008

Abstract
Motivation: The nucleotide sequencing process produces not only the sequence of nucleotides, but also associated quality values. Quality values provide valuable information, but are primarily used only for trimming sequences and generally ignored in subsequent analyses.
Results: This article describes how the scoring schemes of standard alignment algorithms can be modified to take into account quality values to produce improved alignments and statistically more accurate scores. A prototype implementation is also provided, and used to post-process a set of BLAST results. Quality-adjusted alignment is a natural extension of standard alignment methods, and can be implemented with only a small constant factor performance penalty. The method can also be applied to related methods including heuristic search algorithms like BLAST and FASTA.
Availability: Software is available at http://malde.org/~ketil/qaa.
Contact: ketil.malde@imr.no
Supplementary information: Supplementary data are available at Bioinformatics online.