bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Inclusion Body Contaminants on the Oxidative Renaturation of Hen Egg White Lysozyme
Authors: Maachupalli‐Reddy Jhansi , Kelley Brian D. , Clark Eliana De Bernardez 
Published: July 2002

AbstractThe effect of typical contaminants in inclusion body preparations such as DNA, ribosomal RNA, phospholipids, lipopolysaccharides, and other proteins on renaturation rate and yield of hen egg white lysozyme was investigated. Separate experiments were conducted in which known amounts of individual contaminants were added to test their effect on renaturation kinetics. On the basis of a simplified model for the kinetic competition between folding and aggregation, it was found that none of the above contaminants had an effect on the rate of the folding reaction, but some of them significantly affected the rate of the aggregation reaction and, thus, the overall renaturation yield. While ribosomal RNA did not seem to affect the aggregation reaction, plasmid DNA and lipopolysaccharides increased the aggregation rate, resulting in a decrease of about 10% in the overall renaturation yield. Phospholipids were found to improve refolding yields by about 15% by decreasing the overall rate of the aggregation reaction without affecting the rate of the folding reaction. Proteinaceous contaminants which aggregate upon folding, such as β‐galactosidase and bovine serum albumin, were found to significantly decrease renaturation yields by promoting aggregation. This effect was strongly dependent on the concentration of the proteinaceous impurity. On the other hand, the presence of refolding ribonuclease A, which does not significantly aggregate upon folding under the conditions tested in this work, did not affect the renaturation kinetics of lysozyme, even at concentrations as high as 0.7 mg/mL.
Mapping soil texture classes using field textuing, particle size distribution and local knowledge by both conventional and geostatisical methods
Authors: Oberthür T. , Goovaerts P , Dobermann A . 
Published: July 2002

SummaryWe investigated the utility of three interpolation techniques that ignored descriptive `soft' information and one that used it for mapping topsoil texture classes: re‐coding of soil map units within Geographical Information Systems (GIS), Thiessen polygons, and classifcation of probability vectors estimated by ordinary indicator kriging and simple indicator kriging with local prior means. The results were compared with texture maps based on a classifcation of kriged maps of particle size distribution. The methods were applied to two distinct regions, which represent large areas in rain‐fed rice ecosystems and irrigated rice ecosystems. The `hard' databases for both areas contained soil information needed for mapping at regional scales (1:100 000‐1:150 000). These data were complemented with 'soft' information derived from farmers and soil experts (Northeast Thailand) and soil maps (Nueva Ecija, Philippines). Interpolated maps agreed with the texture map based on interpolation of particle size distribution, and ®eld estimates of soil texture proved to be valuable surrogates for laboratory measurements of soil texture classes. The interpolation of categorical data such as soil texture classes allows for upgrading and increasing the resolution of maps in sparsely sampled regions by using simple field measurements. Validation using independent test sets showed that indicator kriging with local prior means performed best in the rain‐fed lands, whereas soft information did not improve the predictions in Nueva Ecija. Local knowledge in a formalized form was valuable in Northeast Thailand and the interpolated soil texture map for this area had an accuracy and resolution to support agronomic decisions at the village scale. The poor quality of the soil map and the fact that the gradually changing variability in young alluvial soils can be modelled with fewer data explained the lower accuracy of simple indicator kriging with local prior means in Nueva Ecija. Thiessen polygons performed well in the undulating rain‐fed lands but were not as reliable as indicator kriging in the gradually changing irrigated lands.
Increasing curvature of the normal fetal ductus arteriosus with advancing gestational age
Authors: Benson C. B. , Brown D. L. , Doubilet P. M. , DiSalvo D. N. , Laing F. C. , Frates M. C. 
Published: July 2002

AbstractIn order to determine whether the configuration of the normal fetal ductus arteriosus changes with increasing gestational age, we prospectively collected oblique transverse sonographic images of the fetal thorax through the ductus arteriosus. Scans from 240 consecutive normal fetuses with gestational age 20 weeks or more were included in the study. The images were reviewed independently by two sonologists and the ductus arteriosus was graded as: (1) straight; (2) mildly curved (C‐shaped, bending < 90° from a straight line); or (3) markedly curved (C‐shaped, bending < 90°, or S‐shaped). In cases where the two sonologists' gradings did not concur, the images were re‐reviewed jointly by both sonologists and a grading was assigned by consensus. Forty‐two cases were rejected, due to inadequate images.The ductus arteriosus was graded in 42 fetuses aged 20–25.9 weeks, 48 at 26–31.9 weeks, 74 at 32–37.9 weeks, and 34 at 38 weeks or more for a total of 198 cases. There was a significant trend to greater curvature with increasing gestational age (p < 0.0001). The frequency of a straight ductus arteriosus decreased steadily from 55% of fetuses aged 20–25.9 weeks to 3% of fetuses at 38 weeks or older, while the frequency of marked curvature increased from 2% in the youngest age group to 56% in the oldest. The proportion with mild curvature showed little variation throughout gestation.In summary, the configuration of the ductus arteriosus is variable but tends to become more curved as pregnancy proceeds. Marked curvature or tortuosity of the ductus arteriosus should not be misinterpreted as a great vessel anomaly. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology
Sex Hormones and Cognitive Function in Older Men
Authors: Yaffe Kristine , Lui Li‐Yung , Zmuda Joeseph , Cauley Jane 
Published: July 2002

OBJECTIVES: Recent studies have suggested that estrogen may improve cognitive function or prevent cognitive decline in older women. Little research has been conducted on exogenous or endogenous sex hormones and cognition in older men, yet it has been hypothesized that testosterone, either directly or by conversion to estrogens, may improve cognitive function. We investigated whether serum level of testosterone and estradiol is associated with cognition in older community‐dwelling men.DESIGN: A cross‐sectional study.SETTING: Population‐based listings in the Monongahela Valley near Pittsburgh, Pennsylvania.PARTICIPANTS: Three hundred ten men (mean age ± standard deviation = 73.0 ± 7.1) who were part of a cohort study.MEASUREMENTS: We measured cognitive function using the Mini‐Mental State Examination (MMSE), Trails B, and Digit Symbol. Sex hormone levels were determined by radioimmunoassay from serum obtained at the time of cognitive testing and analyzed by tertile.RESULTS: No consistent association between total testosterone level and cognitive test scores was observed. However, men with high bioavailable (loosely protein‐bound) testosterone had better cognitive test scores on all three tests (P≤ .001). Total estradiol levels were associated with worse cognitive scores on Digit Symbol (P < .001) and Trails B (P = .002), but bioavailable estradiol levels were not associated with cognitive function. Level of sex hormone binding globulin (SHBG) was negatively associated with cognitive scores on all three tests (P≤ .001). After adjusting for age and education, the statistical significance lessened for bioavailable testosterone (MMSE, P = .086; Digit Symbol, P = .047; Trails B, P = .076) and became nonsignificant for SHBG (all cognitive tests P> .10).CONCLUSIONS: Our findings support the hypothesis that higher levels of bioavailable testosterone, but not of bioavailable estradiol, are associated with better cognitive function in older men. In addition, bioavailable measures of testosterone may better reflect hormone levels available to the brain and thus be more closely associated with central nervous system outcomes such as cognition. Future studies, especially randomized trials, should be undertaken to determine whether testosterone may protect against cognitive decline in older men.
Evening Light Exposure: Implications for Sleep and Depression
Authors: Wallace‐Guy Geralyn M. , Kripke Daniel F. , Jean‐Louis Girardin , Langer Robert D. , Elliott Jeffrey A. , Tuunainen Arja 
Published: July 2002

OBJECTIVES: To examine whether dim illumination in the evening is a factor in sleep disturbances of aging, depression, and circadian phase advance.DESIGN: One‐week continuous recordings were made to record illumination exposure and to infer 24‐hour sleep patterns from wrist activity.SETTING: Recordings took place during normal home and community activities.PARTICIPANTS: Complete data of 154 postmenopausal women, mean age 66.7, were selected from a larger study of participants in the Women's Health Initiative.MEASUREMENTS: Illumination in lux was averaged for 4 hours before bedtime and over 24 hours. Mood was measured using a brief eight‐item screen.RESULTS: Illumination in the 4 hours before bedtime was quite dim: median 24 lux. Nevertheless, evening light exposure was not significantly related to sleep amount (in bed or out of bed) sleep efficiency, sleep latency, wake within sleep, or mood. In contrast, the overall amount of light throughout the 24 hours was negatively correlated with sleep latency, wake within sleep, and depressed mood.CONCLUSIONS: Low evening lighting does not appear to be a crucial factor in sleep and mood disturbances of aging, but overall lighting may contribute to these disturbances.
The benzene ground state potential surface. IV. Discrimination between multiple E1u force field solutions through infrared intensities
Authors: Goodman Lionel , Ozkabak Ali G. , Wiberg Kenneth B. 
Published: July 2002

Accurate values for integrated intensities of the infrared active 13C6H6 fundamentals, ν18, ν19, ν20, and ν11 (Wilson notation) have been measured and redetermined for ν18 and ν19 in C6H6 and C6D6. The 13C6H6 intensities are I18=6.52±0.15, I19=12.60±0.20, I20=55.6±1, and I11=74.6±3 km/mol. Unlike C6H6 and C6D6, interfering transitions in 13C6H6 are minor and these intensities can be used as a critical test for theoretical predictions of atomic polar tensors. The ν18 intensities in C6H6 and C6D6 (7.48±0.15 and 7.09±0.14 km/mol, respectively) and the ν19 intensity in C6D6 (2.51±0.12 km/mol) are measured to be substantially lower than the literature values. The qualitative intensity pattern of benzene in-plane fundamentals uniquely discriminate among the eight possible real E1u force field solutions obtained from frequency information alone. Isotopically invariant dipole moment derivatives, ∂μ/∂S18a, ∂μ/∂S19a, and ∂μ/∂S20a are 0.494±0.005, 0.395±0.016, and 0.770±0.008 D/Å, respectively, obtained from the 13C6H6 experimental intensities and the complete experimental force field of Part II. Using these quantities and the L−1 matrix (Table III), dipole moment gradients for C6H6 become ∂μ/∂Q018a =+0.298, ∂μ/∂Q019a =+0.371, and ∂μ/∂Q020a =+0.814 D/Å. Mode decomposition matrices expressing normal modes of benzene in terms of isotopically labeled molecule modes have been used to definitively determine the C6H6 dipole gradient signs. The signs are in agreement with theoretical calculations. The D6 isotopic labeling effect on C6H6 ν18 intensity provides a sensitive test of E1u force field quality and reveals the inadequacy of present theoretical force field approaches. Ab initio atomic polar tensors have been obtained both at the HF level, using several basis sets up to the 6-311+G(d,p) and at the
MP2 level up to the 6-31+G(d) basis set. The dipole derivative for the CC stretch is highly sensitive to both basis set (particularly diffuse functions) and correlation effects. Qualitative CH and CC stretching dipole derivative and intensity predictions by the MP2/6-31+G(d) calculation are encouraging (i.e., within 15% of the experimental values). However, the same calculation yields 20% and 45% errors for the CH bending dipole derivative and fundamental intensity, respectively.
Neoclassical quasilinear transport theory of fluctuations in toroidal plasmas
Authors: Shaing K. C. 
Published: July 2002

A transport theory of fluctuations with frequencies less than the gyrofrequency in toroidal plasmas is developed to calculate particle and heat fluxes, bootstrap current, Ware pinch flux, and modification to plasma conductivity. It is found that the particle and heat fluxes are proportional to ∑m,n,ωm2(eΦ̃mnω/Te)2, the bootstrap current and Ware pinch flux are proportional to ∑m,n,ωm[(m−nq)/‖m−nq‖] (eΦ̃mnω/Te)2, and the modification
to plasma conductivity is proportional to ∑m,n,ω‖m−nq‖(eΦ̃mnω /Te)2, where m (n) is the poloidal (toridal) mode number for the (m,n) mode with frequency ω, Φ̃mnω is its mode amplitude, e is the electric charge, Te is the electron temperature, and q is the safety factor. Alternatively, in terms of the poloidal wave vector kθ and the parallel wave vector k∥, the particle and heat fluxes are proportional to 〈k2θ〉〈(eΦ̃/Te)2〉, the bootstrap current and Ware pinch flux are proportional to 〈kθk∥/‖k∥‖〉〈(eΦ̃/ Te)2〉, and the modification to plasma conductivity is proportional to 〈‖k∥‖〉〈(eΦ̃/Te)2〉, where 〈Φ̃2〉 is the averaged fluctuation level. Thus the sensitivities of various transport fluxes to plasma fluctuations are different: the most sensitive ones are particle and heat fluxes, the less sensitive ones are bootstrap current and Ware pinch flux, and the least sensitive one is the modification to plasma conductivity. The effects of fluctuations on bootstrap current and Ware pinch flux and on modification to plasma conductivity are smaller than those on particle and heat fluxes by factors of 〈kθk∥/‖k∥‖〉/〈k2
θ〉 and 〈k∥‖〉/〈k2θ〉, respectively. It is demonstrated explicitly that the matrix consisting of these transport coefficients satisfies Onsager symmetry. Furthermore, it is shown that the electron and ion transport are coupled through plasma flows. The theory is employed to discuss some qualitative transport properties observed in toroidal plasma experiments.
Organizational communication and the symbolic construction of police murder investigations 1
Authors: Innes Martin 
Published: July 2002

ABSTRACTThis paper draws upon a range of empirical data to consider the ways in which police murder investigations are symbolically constructed, both within and outside of the police organization. It is argued that a range of communicative formats serve to produce the activities associated with police murder investigations in a way that serves to legitimate the police function to both members of the public and police officers alike. A particular emphasis is placed upon understanding the connections between informal and formal communications, and the instrumental and expressive objectives that variously underpin them.
MDMA toxicity: no evidence for a major influence of metabolic genotype at CYP2D6
Authors: O'DONOHOE ALAN , O'FLYNN KAREN , SHIELDS KEVIN , HAWI ZIARIH , GILL MICHAEL 
Published: July 2002

Abstract3,4 Methylenedioxymethamphetamine (MDMA or ecstasy) has become a major drug of abuse over the last decade. It produces a mixture of systemic and neuropsychological effects. Animal studies show a range of short‐ and long‐term toxic effects, both systemically and neurochemically. In humans, toxicity and death due to the drug have been attributed to a variety of causes, with ‘idiosyncratic’, or non‐dose‐related, reactions often cited. It has recently been established that MDMA is metabolized via the cytochrome P450 enzyme, debrisoquine hydroxylase. This enzyme is coded by the gene CYP2D6. This gene contains mutations which effect the function of the enzyme, and individuals homozygous for these mutations are known as poor metabolizers. Between 3 and 10% of the Caucasian population are thus affected, and therefore may be less able to metabolize MDMA. In this paper we examine the hypothesis that individuals selected on the basis of having had an adverse reaction to MDMA will be more likely than the general population to have homozygous mutations at CYP2D6. We obtained retrospectively seven cases of toxicity or death thought to be due to MDMA. DNA was extracted from these patients, and their genotype ascertained. None of this small sample was shown to be homozygous for the mutation at CYP2D6. Three possible explanations are offered for these results. (1) The non‐dose‐related nature of MDMA toxicity may be due, either alone or in combination, to contaminants in the drug, or ambient environmental/physiological factors. (2) Our genotyping methods may have missed one of the rare additional mutations which effect gene function at CYP2D6. (3) Our study sample may be too small to demonstrate a statistically significant result. A larger study is currently under way.
An Intralysosomal hsp70 Is Required for a Selective Pathway of Lysosomal Protein Degradation
Authors: Agarraberes Fernando A. , Terlecky Stanley R. , Dice J. Fred 
Published: July 2002

Previous studies have implicated the heat shock cognate (hsc) protein of 73 kD (hsc73) in stimulating a lysosomal pathway of proteolysis that is selective for particular cytosolic proteins. This pathway is activated by serum deprivation in confluent cultured human fibroblasts. We now show, using indirect immunofluorescence and laser scanning confocal microscopy, that a heat shock protein (hsp) of the 70-kD family (hsp70) is associated with lysosomes (ly-hsc73). An mAb designated 13D3 specifically recognizes hsc73, and this antibody colocalizes with an antibody to lgp120, a lysosomal marker protein. Most, but not all, lysosomes contain ly-hsc73, and the morphological appearance of these organelles dramatically changes in response to serum withdrawal; the punctate lysosomes fuse to form tubules.
Based on susceptibility to digestion by trypsin and by immunoblot analysis after two-dimensional electrophoresis of isolated lysosomes and isolated lysosomal membranes, most ly-hsc73 is within the lysosomal lumen. We determined the functional importance of the ly-hsc73 by radiolabeling cellular proteins with [3H]leucine and then allowing cells to endocytose excess mAb 13D3 before measuring protein degradation in the presence and absence of serum. The increased protein degradation in response to serum deprivation was completely inhibited by endocytosed mAb 13D3, while protein degradation in cells maintained in the presence of serum was unaffected. The intralysosomal digestion of endocytosed [3H]RNase A was not affected by the endocytosed mAb 13D3. These results suggest that ly-hsc73 is required for a step in the degradative pathway before protein digestion within lysosomes, most likely for the import of substrate proteins.
Peripheral Selection of  T Cell Repertoires: The Role of Continuous Thymus Output
Authors: Tanchot Corinne , Rocha Benedita 
Published: July 2002

We investigated the role of continuous thymus output in the shaping of mature T cell repertoires by studying in vivo the survival of a single clone of mature Rag2-deficient T cell receptor (TCR) transgenic cells at different stages of activation in the absence or presence of thymus export. In the absence of thymus export, TCR-transgenic lymphocytes survived indefinitely in the peripheral pools. When new lymphocytes were produced in the thymus and migrated to the periphery, resident memory T cells were maintained in constant numbers, whereas naive and self-reactive T cells were replaced by recent thymus migrants.
This T cell renewal ensured both the efficiency of recall responses to antigens as memory T cells persisted independently of thymus output, and the capacity of the immune system to respond to new antigen stimulation as the naive T cell pool was continuously renewed. Our results also indicate that thymus export is required to control the number of self-reactive peripheral T cells that may invade the peripheral pools if thymus output fails.
The Role of Virus-Specific Cd8+ Cells in Liver Damage and Viral Control during Persistent Hepatitis B Virus Infection
Authors: Maini Mala K. , Boni Carolina , Lee Chun Kyon , Larrubia Juan R. , Reignat Stephanie , Ogg Graham S. , King Abigail S. , Herberg Jethro , Gilson Richard , Alisa Akeem , Williams Roger , Vergani Diego , Naoumov Nikolai V. , Ferrari Carlo , Bertoletti Antonio 
Published: July 2002

Hepatitis B virus (HBV) is a noncytopathic virus, and the recognition of infected hepatocytes by HBV-specific CD8 cells has been assumed to be the central mechanism causing both liver damage and virus control. To understand the role of cytotoxic T cells in the pathogenesis of HBV infection, we used functional assays that require T cell expansion in vitro and human histocompatibility leukocyte antigen (HLA)-peptide tetramers that allow direct ex vivo quantification of circulating and liver-infiltrating HBV-specific CD8 cells. Two groups of patients with persistent HBV infection were studied: one without liver inflammation and HBV replication, the other with liver inflammation and a high level of HBV replication. Contrary to expectation, a high frequency of intrahepatic HBV-specific CD8 cells was found in the absence of hepatic immunopathology. In contrast, virus-specific T cells were more diluted among liver infiltrates in viremic patients, but their absolute number was similar because of the massive cellular infiltration. Furthermore, inhibition of HBV replication was associated with the presence of a circulating reservoir of CD8+ cells able to expand after specific virus recognition that was not detectable in highly viremic patients with liver inflammation.
These results show that in the presence of an effective HBV-specific CD8 response, inhibition of virus replication can be independent of liver damage. When the HBV-specific CD8 response is unable to control virus replication, it may contribute to liver pathology not only directly but by causing the recruitment of nonvirus-specific T cells.
Nucleosomal DNA property database.
Authors: Levitsky V G , Ponomarenko M P , Ponomarenko J V , Frolov A S , Kolchanov N A 
Published: July 2002

Abstract
MOTIVATION: Chromatin structure plays the crucial role in proper gene functioning. Therefore, it is very important to investigate nucleosomal DNA properties and recognize genome nucleosome positioning sequences. Nevertheless, applying different sequence analysis methods separately is insufficient for complete nucleosomal DNA description. One of the most probable reasons for that is the weakness of nucleosome positioning signals. The present paper offers a set of methods to reveal the most important nucleosomal DNA characteristics and to show a common pattern of nucleosome site properties. RESULTS: A complex approach was used to determine conformational and physicochemical properties that are most significant for nucleosome binding site description. The integrated database of nucleosomal DNA properties is compiled. This database comprises different sections for description of DNA characteristics. Revealing significant DNA characteristics allows the classification of various samples of site sequences and the generation of programs for site recognition. AVAILABILITY: The current version of the database is available at http://wwwmgs.bionet.nsc. ru/system/BDNAvideo/. C-code of the recognition program may be found in the section FEATURE. WWW-available programs for testing arbitrary sequences are accessible at http://wwwmgs.bionet.nsc. ru/Programs/bDNA/NA_bDNA.htm/. The links to the mirror site(s) can be found at http://wwwmgs.bionet.nsc.ru/mgs/links/mirrors.html+ ++.