bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of computed tomography before lumbar puncture: a survey of clinical practice
Authors: Greig P R , Goroszeniuk D 
Published: March 2006

Abstract

Introduction
It is becoming increasingly common to request computed tomography (CT) to rule out space occupying lesions before lumbar puncture (LP), even in patients with no clinical signs. Imaging trends within a busy district general hospital in Oxfordshire, UK were analysed with results used to clarify when imaging should be considered mandatory.

Method
A retrospective six month sample was obtained comprising all adults considered for LP. Observed frequencies of abnormal examination findings compared with abnormal investigations were used to determine sensitivity, specificity, positive predictive, and negative predictive values to assess the validity of using a normal clinical examination as a basis for excluding CT.

Results
64 patients were considered for LP. In total, 58 patients underwent LP, with a single patient receiving two. After an abnormal CT scan, six patients did not undergo a planned LP. In all six of these cases subarachnoid haemorrhage was detected, and in all cases this was considered a probable diagnosis. In no case was an LP precluded by an unsuspected space occupying lesion. Neurological examination showed a sensitivity of 0.72 (0.52 to 0.93), specificity 0.78 (0.64 to 0.91), positive predictive value 0.61 (0.41 to 0.83), and negative predictive value 0.85 (0.73 to 0.97).

Discussion
The high sensitivity and negative predictive values support normal neurological examination as an effective predictor of normal CT scan. This permits the recommendation in cases where subarachnoid haemorrhage is not suspected, a CT scan can be avoided provided there are no abnormal findings on physical or fundoscopic examination.
Investigation and management of severe hyponatraemia in a hospital setting
Authors: Huda M S B , Boyd A , Skagen K , Wile D , van Heyningen C , Watson I , Wong S , Gill G 
Published: March 2006

Abstract

Aims
To evaluate the assessment and management of severe hyponatraemia in a large teaching hospital.

Methods
Inpatients with serum sodium &lt;125 mmol/l were identified prospectively from a laboratory database over a six month period. Notes were examined and data extracted. Case notes were carefully reviewed retrospectively by a consultant endocrinologist with regard to accuracy of the diagnosis and the appropriateness of investigations and management.

Results
104 patients with a serum sodium &lt;125 mmol/l were identified. Mean (SD) age was 69 (14), 52% were female, mean hospital stay was 16 (12) days, and overall mortality 27%. Adequate investigations were rarely performed. Only 28 (26%) had plasma osmolality measured, 29 (27%) urine osmolality, 11 (10%) urinary sodium, 8 (8%) plasma cortisol, and 2 (2%) a short Synacthen test. Comparing the “ward” and “specialist review” diagnoses, there were significant discrepancies for “no cause found” (49% v 27%, p&lt;0.001), alcohol (6% v 11% p&lt;0.01), and syndrome of inappropriate antidiuresis (20% v 32%, p = 0.001). Treatment was often illogical with significant management errors in 33%. These included fluid restriction and intravenous saline given together (4%) and fluid restriction in diuretic induced hyponatraemia (6%). Mortality was higher in the group with management errors (41% v 20% p = 0.002).

Conclusion
Severe hyponatraemia is a serious condition, but its investigation and evaluation is often inadequate. Some treatment patterns seem to be arbitrary and illogical, and are associated with higher mortality.
Emotions in Vowel Segments of Continuous Speech: Analysis of the Glottal Flow Using the Normalised Amplitude Quotient
Authors: Airas Matti , Alku Paavo 
Published: March 2006

Abstract
Emotions in short vowel segments of continuous speech were analysed usinginverse filtering and a recently developed glottal flow parameter, the normalisedamplitude quotient (NAQ). Simulated emotion portrayals were produced by 9 professionalstage actors. Separated /a:/ vowel segments were inverse filtered andparameterised using NAQ. Statistical analyses showed significant differencesamong most of the emotions studied. Results also demonstrated clear gender differences.Inverse filtering, together with NAQ, was shown to be a promisingmethod for the analysis of emotional content in continuous speech.
Production of Weak Elements in Speech – Evidence from F₀ Patterns of Neutral Tone in Standard Chinese
Authors: Chen Yiya , Xu Yi 
Published: March 2006

AbstractMany weak elements in speech, such as schwa in English and neutral tone inStandard Chinese, are commonly assumed to be unspecified or underspecifiedphonologically. The surface phonetic values of these elements are assumed toderive from interpolation between the adjacent phonologically specified elementsor from the spreading of the contextual phonological features. In the present study,we re-evaluate this view by investigating detailed F0 contours of neutral-tone syllablesin Standard Chinese, which are widely accepted as toneless underlyingly. Werecorded sentences containing 0-3 consecutive neutral-tone syllables at twospeaking rates with two focus conditions. Results of the experiment indicate thatneutral-tone syllables do have a target that is independent of the surroundingtones, which is likely to be static and mid. Furthermore, the neutral tone is found tobe different from the full lexical tones in the manner with which the underlyingtonal target is implemented: it is slow and ineffective both in overcoming the influenceof the preceding full lexical tone and in approaching its own target. Applyingthe recently proposed pitch target approximation model, we conclude that theneutral tone differs from the other lexical tones in Standard Chinese not only interms of its mid target, but also in terms of the weak articulatory strength withwhich this target is implemented. Finally, we suggest that this new understandingis potentially applicable to other weak elements in speech.
Functional Relevance of Golgi- and Plasma Membrane-Localized Endothelial NO Synthase in Reconstituted Endothelial Cells
Authors: Zhang Qian , Church Jarrod E. , Jagnandan Davin , Catravas John D. , Sessa William C. , Fulton David 
Published: March 2006

Objective—We have previously shown in COS-7 cells that targeting of endothelial NO synthase (eNOS) to the Golgi or plasma membrane (PM) regulates the mechanism and degree of eNOS activation. However, little is known about the functional significance of eNOS targeting in endothelial cells (ECs). The goal of the current study was to isolate these 2 pools of enzyme in ECs and determine their functional significance in response to agonist stimulation and manipulation of membrane cholesterol levels.Methods and Results—Using an RNA interference strategy, we generated stable populations of ECs that had >90% inhibition of eNOS expression and lacked the ability to produce NO. Reconstitution of these eNOS “knockdown” ECs with Golgi- and PM-targeted eNOS restored the ability of ECs to produce NO. Calcium-dependent agonists were the more efficient stimulus for the PM-restricted eNOS in ECs. In contrast, Golgi eNOS was less responsive to both calcium- and Akt-dependent agonists. eNOS restricted to the PM was more sensitive to manipulation of membrane cholesterol levels and was significantly attenuated by modified low-density lipoprotein.Conclusions—Within ECs, the PM is the most efficient location to produce NO but is more vulnerable to cholesterol levels and modified low-density lipoprotein.
Observed and Modeled Greenland Ice Sheet Snow Accumulation, 1958–2003, and Links with Regional Climate Forcing
Authors: Hanna Edward , McConnell Joe , Das Sarah , Cappelen John , Stephens Ag 
Published: March 2006

Abstract
Annual and monthly snow accumulation for the Greenland Ice Sheet was derived from ECMWF forecasts [mainly 40-yr ECMWR Re-Analysis (ERA-40)] and further meteorological modeling. Modeled accumulation was validated using 58 ice core accumulation datasets across the ice sheet and was found to be 95% of the observed accumulation on average, with a mean correlation of 0.53 between modeled and observed. Many of the ice core datasets are new and are presented here for the first time. Central and northern interior parts of the ice sheet were found to be ∼10%–30% too dry in ERA-40, in line with earlier ECMWF analysis, although too much (&gt;50% locally) snow accumulation was modeled for interior southern parts of Greenland. Nevertheless, 47 of 58 sites show significant correlation in temporal variability of modeled with observed accumulation. The model also captures the absolute amount of snow accumulation at several sites, most notably Das1 and Das2 in southeast Greenland. Mean modeled accumulation over the ice sheet was 0.279 (standard deviation 0.034) m yr−1 for 1958–2003 with no significant trend for either the ice sheet or any of the core sites. Unusually high accumulation in southeast Greenland in 2002/03 leads the authors to study meteorological synoptic forcing patterns and comment on the prospect of enhanced climate variability leading to more such events as a result of global warming. There is good agreement between precipitation measured at coastal meteorological stations in southern Greenland and accumulation modeled for adjacent regions of the ice sheet. There is no significant persistent relation between the North Atlantic Oscillation index and whole or southern Greenland accumulation.
Recent Trends in Four Common Stability Indices Derived from U.S. Radiosonde Observations
Authors: DeRubertis Diana 
Published: March 2006

Abstract
Daily sounding-derived atmospheric stability indices are typically employed for short-term severe weather forecasts. Over longer time periods, these indicators may convey changes in the potential for severe storm development over the United States. Daily (0000 UTC) observations from 48 radiosonde stations in the contiguous United States are extracted to assemble a ∼50 yr record of four common stability indices: the Lifted Index, the K-Index, convective available potential energy (CAPE), and the Air Force Severe Weather Threat Index. Because of radiosonde data inhomogeneities, the 1973–97 period is the focus of the analysis. Trends in the mean and extreme values of daily index observations are calculated for spring and summer seasons. In addition, climatological mean indices, as well as the mean frequency of index extremes, are determined for all U.S. regions. At stations free of obvious data discontinuities, the early part of the record (1948–65) is compared with more recent periods.
In spring, few significant changes in either index means or extremes are reported. However, in summer, widespread trends toward enhanced instability appear, particularly in the Lifted Index, the K-Index, and CAPE. Stations in the Plains and southern states show the most consistent increases in severe weather potential, while significant trends in index extremes are uncommon in the western region, possibly due to the rarity of severe weather there.
Variability and the Severity of the “Little Dry Season” in Southwestern Nigeria
Authors: Adejuwon James O. , Odekunle Theophilus O. 
Published: March 2006

AbstractThe Little Dry Season (LDS) of West Africa is manifested as a decline in both the frequency and amount of daily rainfall for a number of weeks halfway through the rainy season. The mean or climatological LDS is derived from the slope of the cumulative percentage graph of 5-day mean rainfall (daily rainfall data between 1961 and 2000). LDS variability analysis was carried out using the concept of relative variability. The results obtained showed that LDS is observed from mid-July to mid-September along the coast. Northward and eastward the period of occurrence decreases. In general, the phenomenon is not observed north of the eastward-flowing or east of the southward-flowing River Niger. The results also show considerable interannual variability. Variability was highest along the southwestern coast and declined inland northward and eastward. Variability was highest with respect to total rainfall, followed by length and number of rain days. There are indications that for most years the LDS was only relatively dry while in certain years it represented a period of drought. The occurrence of the LDS in space and time is explained by the movements of the intertropical discontinuity and its associated zone of rainfall. Interannual variability in occurrence and severity are determined by the Walker Circulation phenomenon. Variability in the severity of the LDS has mixed implications for agricultural practices.
Sea Surface Temperature Daytime Climate Analyses Derived from Aerosol Bias-Corrected Satellite Data
Authors: Nalli Nicholas R. , Reynolds Richard W. 
Published: March 2006

Abstract
This paper describes daytime sea surface temperature (SST) climate analyses derived from 16 years (1985–2000) of reprocessed Advanced Very High Resolution Radiometer (AVHRR) Pathfinder Atmospheres (PATMOS) multichannel radiometric data. Two satellite bias correction methods are employed: the first being an aerosol correction, the second being an in situ correction of satellite biases. The aerosol bias correction is derived from observed statistical relationships between the slant-path aerosol optical depth and AVHRR multichannel SST (MCSST) depressions for elevated levels of tropospheric and stratospheric aerosol. Weekly analyses of SST are produced on a 1° equal-angle grid using optimum interpolation (OI) methodology. Four separate OI analyses are derived based on 1) MCSST without satellite bias correction, 2) MCSST with aerosol satellite bias correction, 3) MCSST with in situ correction of satellite biases, and 4) MCSST with both aerosol and in situ corrections of satellite biases. These analyses are compared against the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager OI SST, along with the extended reconstruction SST in situ analysis product. The OI analysis 1 exhibits significant negative and positive biases. Analysis 2, derived exclusively from satellite data, reduces globally the negative bias associated with elevated atmospheric aerosol, and subsequently reveals pronounced variations in diurnal warming consistent with recently published works. Analyses 3 and 4, derived from in situ correction of satellite biases, alleviate biases (positive and negative) associated with both aerosol and diurnal warming, and also reduce the dispersion. The PATMOS OISST 1985–2000 daytime climate analyses presented here provide a high-resolution (1° weekly) empirical database for studying seasonal and interannual climate processes.
The SCL relative LYL-1 is required for fetal and adult hematopoietic stem cell function and B-cell differentiation
Authors: Capron Claude , Lécluse Yann , Kaushik Anna Lila , Foudi Adlen , Lacout Catherine , Sekkai Dalila , Godin Isabelle , Albagli Olivier , Poullion Isabelle , Svinartchouk Fedor , Schanze Elisabeth , Vainchenker William , Sablitzky Fred , Bennaceur-Griscelli Annelise , Duménil Dominique 
Published: March 2006

AbstractHematopoietic stem cells (HSCs) arise, self-renew, or give rise to all hematopoietic lineages through the effects of transcription factors activated by signaling cascades. Lyl-1 encodes a transcription factor containing a basic helix-hoop-helix (bHLH) motif closely related to scl/tal, which controls numerous decisions in embryonic and adult hematopoiesis. We report here that Lyl-1 null mice are viable and display normal blood cell counts, except for a reduced number of B cells resulting from a partial block after the pro-B stage. Nevertheless, the deletion of Lyl-1 results in a diminution in the frequency of immature progenitors (Lin–, CD34–, sca-1+, c-kit+ [LSK], and LSK-side population [LSK-SP]) and in S12 colony-forming unit (CFU-S12) and long-term culture-initiating cell (LTC-IC) content in embryonic day 14 fetal liver (E14 FL) and adult bone marrow (BM). More important, Lyl-1–/– E14 FL cells and BM are severely impaired in their competitive reconstituting abilities, especially with respect to B and T lineage reconstitution. Thus, ablation of Lyl-1 quantitatively and functionally affects HSCs, a cell population that transcribes Lyl-1 more actively than their differentiated progenies. Our results demonstrate for the first time that Lyl-1 functions are important for HSC properties and B-cell differentiation and that they are largely distinct from scl functions.
Chemokine receptor targeting efficiently directs antigens to MHC class I pathways and elicits antigen-specific CD8+ T-cell responses
Authors: Schiavo Roberta , Baatar Dolgor , Olkhanud Purevdorj , Indig Fred E. , Restifo Nicholas , Taub Dennis , Biragyn Arya 
Published: March 2006

AbstractChemokines are key controllers of cell trafficking and are involved in numerous pathologic and inflammatory conditions. However, the fate of a chemokine ligand, once it is endocytosed with its receptor, remains obscure. Here, using chemokine–tumor antigen fusion constructs, we demonstrate for the first time that chemokines are internalized to early/late endosomal and lysosomal compartments through a clathrin-dependent process and subsequently delivered to the cytosol for proteasomal processing, facilitating efficient cross-presentation to the TAP-1–dependent MHC class I processing pathway. These data not only elucidate the intracellular fate of chemokine ligands upon receptor uptake, but also demonstrate the superior carrier potency of chemokines for delivering self-antigens to both class I and II processing pathways to induce CD8+ and CD4+ T-cell responses.
Antibody-dependent cellular cytotoxicity (ADCC) is mediated by genetically modified antigen-specific human T lymphocytes
Authors: Clémenceau Béatrice , Congy-Jolivet Nicolas , Gallot Géraldine , Vivien Régine , Gaschet Joëlle , Thibault Gilles , Vié Henri 
Published: March 2006

AbstractIn the context of transplantation, donor and virus-specific T-lymphocyte infusions have demonstrated the dramatic potential of T cells as immune effectors. Unfortunately, most attempts to exploit the T-cell immune system against nonviral malignancies in the syngeneic setting have been disappointing. In contrast, treatments based on monoclonal antibodies (Abs) have been clinically successful and have demonstrated the clinical relevance of several antigens as therapeutic targets and the importance of the antibody-dependent cellular cytotoxicity (ADCC) pathway. In the present study, we considered the possibility of arming specific T cells with a receptor that would enable them to mediate ADCC. After transduction with a CD16/γ receptor gene, CD4+ and CD8+ cytotoxic T lymphocytes displayed stable expression of the CD16 receptor at their surface. In the absence of Ab, CD16/γ expression did not affect the capacity of specific T lymphocytes to kill their target following “natural” T-cell receptor recognition. When tested against the autologous B-lymphoblastoid cell line (BLCL) coated with anti-CD20 mAb, the newly expressed Fc receptor enabled the T cells to kill the BLCL through ADCC. Adoptive transfer of such newly designed immune effector may be considered to increase antibody efficiency by harnessing the immune potential of T cells.
Vascular endothelial cell–specific phosphotyrosine phosphatase (VE-PTP) activity is required for blood vessel development
Authors: Bäumer Sebastian , Keller Linda , Holtmann Astrid , Funke Ruth , August Benjamin , Gamp Alexander , Wolburg Hartwig , Wolburg-Buchholz Karen , Deutsch Urban , Vestweber Dietmar 
Published: March 2006

AbstractVE-PTP, a receptor-type phosphotyrosine phosphatase, associates with the tyrosine kinase receptor Tie-2 and VE-cadherin and enhances the adhesive function of the latter. Here, VE-PTP was found to be restricted to endothelial cells, with a preference for arterial endothelium. Mutant mice expressing a truncated, secreted form of VE-PTP lacking the cytoplasmic and transmembrane domains and the most membrane-proximal extracellular fibronectin type III repeat, showed severe vascular malformations causing lethality at 10 days of gestation. Although blood vessels were initially formed, the intraembryonic vascular system soon deteriorated. Blood vessels in the yolk sac developed into dramatically enlarged cavities. In explant cultures of mutant allantoides, endothelial cells were found next to vessel structures growing as cell layers. No signs for enhanced endothelial apoptosis or proliferation were observed. Thus, the activity of VE-PTP is not required for the initial formation of blood vessels, yet it is essential for their maintenance and remodeling.
Differential Spatial Approximation between Secretin and Its Receptor Residues in Active and Inactive Conformations Demonstrated by Photoaffinity Labeling
Authors: Dong Maoqing , Hosohata Keiko , Pinon Delia I. , Muthukumaraswamy Natesa , Miller Laurence J. 
Published: March 2006

AbstractUnderstanding of the conformational changes in G protein-coupled receptors associated with activation and inactivation is of great interest. We previously used photoaffinity labeling to elucidate spatial approximations between photolabile residues situated throughout the pharmacophore of secretin agonist probes and this receptor. The aim of the current work was to develop analogous photolabile secretin antagonist probes and to explore their spatial approximations. The most potent secretin antagonist reported is a pseudopeptide ([ψ4, 5]secretin) in which the peptide bond between residues 4 and 5 was replaced by a ψ(CH2-NH) peptide bond isostere. We have developed a series of [ψ4, 5]secretin analogs incorporating photolabile benzoyl phenylalanine residues in positions 6, 22, and 26. Each bound to the secretin receptor saturably and specifically, with affinity similar to their parental peptide. At concentrations with no measurable agonist activity, each probe covalently labeled the secretin receptor. Peptide mapping using proteolytic cleavage, immunoprecipitation, and radiochemical sequencing identified that each of these three probes labeled the amino terminus of the secretin receptor. Whereas the position 22 probe labeled the same residue as its analogous agonist probe and the position 6 probe labeled a residue within two residues of that labeled by its analogous agonist probe, the position 26 probe labeled a site 16 residues away from that labeled by its analogous agonist probe. Thus, whereas structurally related agonist and antagonist probes dock in the same general region of this receptor, conformational differences in active and inactive states result in substantial differences in spatial approximation at the carboxyl-terminal end of secretin analogs.
Breath Analysis: Potential for Clinical Diagnosis and Exposure Assessment
Authors: Cao Wenqing , Duan Yixiang 
Published: March 2006

AbstractBreath tests are among the least invasive methods available for clinical diagnosis, disease state monitoring, and environmental exposure assessment. In recent years, interest in breath analysis for clinical purposes has increased. This review is intended to describe the potential applications of breath tests, including clinical diagnosis of diseases and monitoring of environmental pollutant exposure, with emphasis on oxidative stress, lung diseases, metabolic disorder, gastroenteric diseases, and some other applications. The application of breath tests in assessment of exposure to volatile organic compounds is also addressed. Finally, both the advantages and limitations of breath analysis are summarized and discussed.