bluuebunny/crossref_metadata_2025_split huggingface dataset:
IgG and IgA subclass mRNA-bearing plasma cells in periodontitis gingival tissue and immunoglobulin levels in the gingival crevicular fluid
Authors: Takahashi K , Mooney J , Frandsen E V G , Kinane D F 
Published: November 2003

Abstract
The humoral immune response, especially the production of IgG and IgA, is considered to have a protective role in the pathogenesis of periodontal disease, but the precise mechanisms are still unknown. In order to determine local IgG and IgA production, we investigated the presence of human IgG and IgA subclass mRNA-bearing plasma cells within periodontal tissue by in situ hybridization using digoxigenin-labelled oligonucleotide probes in 24 gingival biopsy samples (pocket depth&gt;5 mm) which were obtained from eight patients with adult periodontitis. Furthermore, we examined IgG and IgA subclass proteins and digested IgA1 Fab portions in the gingival crevicular fluid (GCF), corresponding to the sites from which the tissues were taken, by ELISA. IgG and IgA subclass mRNA-expressing cells were detected in all serial formalin-fixed/paraffin-embedded gingival tissue sections sampled. Plasma cells showed strong cytoplasmic staining with a high contrast and a good retention of morphology with these probes. IgG1 mRNA-expressing cells were predominant (mean 63%) and IgG2 mRNA-expressing cells were present at around 23% of total IgG plasma cells, while IgG3 and IgG4 mRNA-expressing cells were present to a much lesser extent (3% and 10%, respectively). Similar proportions of IgG subclass proteins in GCF were detected, which were also consistent with ‘normal’ serum levels. In terms of IgA subclass, IgA1 mRNA-positive cells were predominant (mean 65.1%, P&lt;0.001). In contrast, IgA2 protein in the GCF samples were detected at higher concentrations than IgA1 (P&lt;0.001). The ratio of total IgG to IgA mRNA-positive plasma cells was ≈7.5:1. There was a good correlation between the amounts of IgG subclass proteins in GCF and the number of IgG subclass mRNA-positive cells in the same sites, but not between IgA subclass proteins and the number of IgA subclass mRNA-positive cells. These data suggest that IgG and IgA subclass proteins can be locally produced in the periodontitis gingiva. In addition, as we detected IgA1 Fab fragments in GCF, this is further confirmation that secreted IgA1 protein in GCF may be digested by periodontal bacteria.
Serum levels of soluble Fas/APO-1 (CD95) and its molecular structure in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases
Authors: Jodo S , Kobayashi S , Kayagaki N , Ogura N , Feng Y , Amasaki Y , Fujisaku A , Azuma M , Yagita H , Okumura K , Koike T 
Published: November 2003

Abstract
There are two major forms of the Fas molecule, membranous Fas and soluble Fas (sFas). To clarify the clinical significance of sFas in autoimmune diseases, we designed a sandwich ELISA to determine serum concentrations of sFas and its molecular structure, and we then analysed the correlation between levels of sFas and laboratory findings in patients with SLE and other autoimmune diseases. The levels of serum sFas were significantly higher in SLE patients than in subjects with other autoimmune diseases and in healthy donors, and the frequency of a positive serum sFas was much greater in SLE patients with high SLE disease activity index scores than in those with low scores. In addition, sFas-positive SLE patients showed a significant difference in various laboratory parameters from sFas-negative SLE patients. Serial measurements of serum sFas levels in SLE patients with active disease revealed that the elevated level of sFas dramatically decreased with improvement in clinical and laboratory findings, following corticosteroid therapy. We propose that the serum level of sFas can serve as an appropriate marker for evaluating SLE disease activity. Serum sFas is heterogeneous with respect to molecular structure, thus several mechanisms are involved in the generation of sFas.
Wasting in the acquired immune deficiency syndrome is associated with multiple defects in the serum insulin‐like growth factor system
Authors: Frost Robert , Fuhrer Jack , Steigbigel Roy , Mariuz Peter , Lang Charles , Gelato Marie 
Published: November 2003

OBJECTIVE The aim of this investigation was to characterize the GH–IGF axis of patients with AIDS associated wasting. A special emphasis was placed on determining whether IGF binding proteins (IGFBPs) of patients who have lost more than 10% of their ideal body mass are structurally different from the IGFBPs of patients with no weight loss.DESIGN AND PATIENTS A cross‐sectional study of 11 AIDS patients was performed to determine whether the IGF system is abnormal in AIDS patients with wasting. Seven additional AIDS patients were followed longitudinally to determine whether AIDS patients experience long‐term changes to their IGF system.MEASUREMENTS Serum levels of GH and IGF‐I were measured by radioimmunoassay, IGF‐II was measured by radioreceptor assay, and IGFBP‐1 was measured by an enzyme linked immunoassay. IGFBP‐3 and IGFBP‐3 protease activity were measured by ligand blotting and a BP‐3 protease assay, respectively. IGFBP‐3 ternary complex formation and IGFBP‐1 phosphovariants were analysed by non‐denaturing PAGE.RESULTS AIDS patients who had lost more than 10% of their ideal body mass demonstrated a 55% reduction in serum IGF‐I (81 vs 179 μg/l) and a 70% reduction in IGF‐II (226 vs 776 μg/l), compared to healthy HIV negative subjects. IGF‐I levels were depressed, in some patients, despite high serum levels of GH. AIDS patients who had lost more than 10% of their ideal body mass had low levels of IGFBP‐3 and a reduced ability to form the IGFBP‐3 ternary complex. The IGFBP‐3 ternary complex could be restored only upon addition of pure IGFBP‐3 and acid labile subunit to serum. Serum IGFBP‐1 was increased more than threefold compared to control subjects (90 vs 24 μg/l). IGFBP‐1 was present as a free phosphoprotein in AIDS patients with low levels of IGF‐I and in a bound form when serum IGF‐I levels were normal. Changes in the GH–IGF axis were sustained for up to 25 months in AIDS patients with wasting.CONCLUSIONS AIDS wasting is associated with a GH resistant state that results in low levels of serum IGF‐I, IGF‐II and IGFBP‐3, elevated levels of phosphorylated IGFBP‐1, and a reduced ability to form the IGFBP‐3 ternary complex.
Ecological implications of xylem cavitation for several Pinaceae in the Pacific Northern USA
Authors: Piñol J. , Sala A. 
Published: November 2003

Abstract1. Xylem hydraulic properties and vulnerability to cavitation (determined using the air‐injection method) were studied in six Pinaceae of the northern Rocky Mountains: Pinus ponderosa, Pseudotsuga menziesii, Larix occidentalis, Pinus contorta, Pinus albicaulis and Abies lasiocarpa. We tested whether species extending into drier habitats exhibited increased resistance to water stress‐induced cavitation, and whether there is a trade‐off between xylem transport capacity and resistance to cavitation.2. At lower elevations the more drought‐tolerant P. ponderosa was much less resistant to cavitation than the codominant P. menziesii. Greater vulnerability to cavitation in P. ponderosa was compensated for, at least in part, by increased stomatal control of water loss (inferred from carbon isotope discrimination) and by increased sapwood to leaf area ratios. Similar differences, but less pronounced, were found in codominant species at higher elevations.3. Leaf specific hydraulic conductivity was negatively correlated with mean cavitation pressure. When species were separated into pines and non‐pines, sapwood specific conductivity and mean cavitation pressure were also negatively correlated within each of the two groups.4. Our results indicate that within the evergreen conifers examined, greater resistance to water stress‐induced cavitation is not required for survival in more xeric habitats, and that there is a trade‐off between xylem conductance and resistance to cavitation.
Torpor, arousal and activity of hibernating Greater Horseshoe Bats (Rhinolophus ferrumequinum)
Authors: Park K. J. , Jones G. , Ransome R. D. 
Published: November 2003

Abstract1. Patterns of torpor, arousal and activity in free‐living Greater Horseshoe Bats, Rhinolophus ferrumequinum (Schreber), were investigated during the hibernation period by using temperature‐sensitive radio‐transmitters.2. Torpor bouts varied between 0·1 and 11·8 days, with individual means ranging from 1·3 to 7·4 days. Torpor bout duration decreased with increasing ambient temperature.3. Activity duration varied from 37 min to 54 h 24 min, with individual means ranging from 2 : 29 to 8 : 58 h. Activity duration increased with ambient temperatures above approximately 10 °C.4. Ten of 11 bats synchronized their arousals with dusk. The circadian rhythm of one bat showed a free‐running pattern over a period of about 5 weeks. Arousals were more highly synchronized, and closer to dusk, in individuals with lower body condition.5. That bats forage in mild weather is supported by the strong synchronization of arousals with dusk, especially in bats with low body condition.6. Patterns of torpor and subsequent activity are consistent with predictions that torpor lasts until a critical metabolic or water imbalance is achieved. Because metabolism and water loss are temperature‐dependent, torpor bout duration decreases with increasing temperature. The imbalance is corrected during subsequent activity, which is relatively constant in duration until a temperature threshold of 10 °C, above which increasing levels of foraging lead to longer activity bouts.
Spatial and physical heterogeneity of N supply from soil does not influence N capture by two grass species
Authors: Hodge A. , Stewart J. , Robinson D. , Griffiths B. S. , Fitter A. H. 
Published: November 2003

Abstract1. Plant responses after addition of nitrogen‐rich complex organic material (Lolium perenne L. shoots), differing in physical (coarsely cut or finely ground) and spatial (uniform dispersion or discrete patches) heterogeneity, were examined.2. The organic material was added to microcosm units containing L. perenne and Poa pratensis L. as monocultures or mixed swards in order to examine how species composition affected exploitation of the added 15N‐labelled N source.3. Capture of N (as 15N) from the organic material was followed by harvesting individual shoots. Poa pratensis captured more N from the added material when in mixtures with L. perenne than when in monoculture, particularly from the milled material. Capture of N by L. perenne shoots was not affected by either sward composition or method of organic material placement.4. At final harvest (70 days after addition of the organic material), roots from P. pratensis monocultures had greater dry weights, lengths and N contents than those from L. perenne monocultures; P. pratensis shoot dry weights were also greater.5. Capture by swards of N from the added organic material was the same (≈26% of that originally available) regardless of sward composition or organic material placement. However, within the mixed swards P. pratensis captured more N than L. perenne (≈18 and 9%, respectively).
A novel DNA polymerase in the hyperthermophilic archaeon, Pyrococcus furiosus: gene cloning, expression, and characterization
Authors: Uemori Takashi , Sato Yoshimi , Kato Ikunoshin , Doi Hirofumi , Ishino Yoshizumi 
Published: November 2003

Background:In many respects Archaea are much more like eukaryotes than prokaryotes with respect to the conservation of many of the components involved in transcription, translation and DNA replication. So far, only a few DNA polymerases with structures similar to those of eukaryotic DNA polymerase α have been found in Archaea. The identification and characterization of all the DNA polymerases of one archaeon would add considerably to our knowledge of the basic mechanisms of DNA replication in these organisms.Results:We have identified a novel DNA polymerase composed of two proteins, DP1 and DP2, with molecular weights of 69 294 Da and 143 161 Da, respectively, in the hyperthermophilic archaeon, Pyrococcus furiosus, and have cloned the corresponding genes which are tandemly arranged on the Pyrococcus genome. No significant sequence homology was found between these two proteins and other known DNA polymerases. The pol genes were transcribed as part of a single operon that additionally contained genes homologous to the cdc18+/CDC6 and Dmc1/Rad51 family of proteins. We purified the Pyrococcus DNA polymerase from Escherichia coli strains expressing the cloned genes and characterized its activity. It possesses strong 3′  →  5′ exonucleolytic activity and has a template‐primer preference which is characteristic of a replicative DNA polymerase.Conclusion:In P. furiosus, we identified a second DNA polymerase encoded by two genes, neither of which display significant homology to any other known DNA polymerase. Both the enzymatic properties of the enzyme and the gene organization raise the possibility that this enzyme might be the replicative DNA polymerase of P. furiosus.
χ*, a χ‐related 11‐mer sequence partially active in an E. coli recC* strain
Authors: Handa Naofumi , Ohashi Seishi , Kusano Kohji , Kobayashi Ichizo 
Published: November 2003

Background:χ sequence (5′GCTGGTGG) of Escherichia coli was first identified as a site that increased the plaque size of bacteriophage λ. Subsequent studies showed that this site is responsible for both the attenuation of RecBCD exonuclease activity and the promotion of RecA, RecBCD‐mediated recombination. It is known that bacteriophage λ containing the χ site makes very small plaques on a recC* (recC1004) mutant because χ is not recognized by the RecBC*D mutant enzyme.Results:We cloned E. coli chromosomal fragments in λ which allowed λ to form larger plaques on this recC* mutant. The fragments were found to share a χ‐like 11‐mer sequence, 5′GCTGGTGCTCG. Substitution of these fragments with a synthetic 11‐mer of this sequence and single‐base‐pair substitution analysis of its last four nucleotides demonstrated that this sequence is both necessary and sufficient for the observed activity. The sequence, designated χ* (chi‐star), protected rolling‐circle DNA replication in the recC* mutant and in the recBCD+ strain, most likely because it attenuated the exonuclease activity of the RecBC*D and RecBCD+ enzyme. χ*, did not significantly stimulate λ recombination in two assays.Conclusion:We have discovered that a mutant RecBCD enzyme responds, in vivo, to a longer χ variant.
Temporal regulation of the mid‐prepupal gene FTZ‐F1: DHR3 early late gene product is one of the plural positive regulators
Authors: Kageyama Yuji , Masuda Shoko , Hirose Susumu , Ueda Hitoshi 
Published: November 2003

Background:Various ecdysteroid responsive genes play important roles in insect moulting and metamorphosis. Late FTZ‐F1, a member of the nuclear receptor superfamily, is a unique transcription factor which is induced by a pulse exposure of 20‐hydroxyecdysone. Elucidation of the regulation mechanism of this gene during prepupal period will help our understanding of metamorphosis at a molecular level.Results:Using transgenic fly lines carrying various transcription regulatory regions of the FTZ‐F1 gene fused to the LacZ gene, we investigated cis‐regulatory elements in the late FTZ‐F1 transcription unit. The region which governs the stage‐specific expression during pre‐pupal period was narrowed down to 1.2 kb, from –0.7 to +0.5 kb relative to the transcription start site. Electrophoresis mobility shift assays using staged extracts and various probes within the stage‐specific region allowed us to identify binding sites for DHR3, an early late gene product, around 170 and 450 bp downstream of the transcription initiation site. Mutations disrupting these binding sites reduced the reporter gene expression without affecting the stage specificity.Conclusions:Our deletion and mutation studies of the cis‐regulatory element of the FTZ‐F1 gene suggest that the DHR3 binding sites located in the 5′ non‐coding region are involved in the prepupal expression of the gene. These DHR3 binding sites confer high level expression while other elements are also involved in stage‐specific expression.
Loss of teratogenic response to 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) in mice lacking the Ah (dioxin) receptor
Authors: Mimura Junsei , Yamashita Keisuke , Nakamura Kenji , Morita Masanobu , Takagi Toshio N. , Nakao Kazuki , Ema Masatsugu , Sogawa Kazuhiro , Yasuda Mineo , Katsuki Motoya , Fujii‐Kuriyama Yoshiaki 
Published: November 2003

Background:The aryl hydrocarbon receptor (AhR or dioxin receptor) is a ligand‐activated transcription factor that is considered to mediate pleiotropic biological responses such as teratogenesis, tumour promotion, epithelial hyperplasia and the induction of drug‐metabolizing enzymes to environmental contaminants usually represented by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD). In contrast to the role of AhR in the regulatory mechanism of xenobiotic‐metabolizing enzymes, there is no direct proof that the AhR is involved in the teratogenic effects of TCDD.Results:To gain insight into the physiological and teratogenic role of the AhR, we have used gene targeting in mice to disrupt the murine Ahr gene by homologous recombination. Ahr‐null mice were viable and fertile and were apparently normal at birth, but displayed a slightly slower growth rate than wild‐type mice for the first few weeks of life. When pregnant dams were administered with TCDD by gavage, at a dose of 40 μg/kg body weight at gestation day 12.5, none of the Ahr‐null mutant foetuses were sensitive to the teratogenic effects of TCDD, although almost all wild‐type foetuses suffered from cleft palate and hydronephrosis. In heterozygous Ahr+/− genotypes, nearly all foetuses suffered from hydronephrosis in response to TCDD treatment, while haplo‐insufficiency was observed in the incidence of cleft palate.Conclusion:These results clearly show that the AhR is involved in the malformation of the palate and kidney in mouse embryos caused by TCDD and suggests that the mechanism of its involvement differs between the cleft palate and hydronephrosis.
Nuclear accumulation of Saccharomyces cerevisiae Mcm3 is dependent on its nuclear localization sequence
Authors: Young Michael R. , Suzuki Katsunori , Yan Hong , Gibson Susan , Tye Bik K. 
Published: November 2003

Background:The proteins of the Mcm2‐7 family are required for the initiation of DNA replication. In Saccharomyces cerevisiae the nuclear envelope does not break down during the mitotic phase of the cell cycle. Large nuclear proteins, such as the Mcm proteins, which accumulate in the nucleus during specific portions of the cell cycle, must have regulated mechanisms to direct their entry into the nucleus.Results:We have identified a nuclear localization sequence (NLS) in Mcm3, and demonstrated that it is necessary for the translocation of Mcm3 into the nucleus and sufficient for directing Escherichia coliβ‐galactosidase to the nucleus. Immediately adjacent to the nuclear localization sequence are four potential sites for phosphorylation by Cdc28. Mutagenesis of all four sites has no immediate phenotypic effect on cell growth or viability, nor does it affect nuclear accumulation of Mcm3, although two‐dimensional protein gel analysis has shown that at least some of these sites are normally phosphorylated in vivo. Substitution of the Mcm3 NLS by the SV40 large T‐antigen NLS also directs the nuclear accumulation of the Mcm3‐T‐antigen protein, although cell growth is compromised. Replication activity in cells bearing either the Mcm3‐Cdc28 phosphorylation site mutations or the Mcm3 T‐antigen NLS substitution, as measured by plasmid stability assays, is comparable to activity in wild‐type cells.Conclusions:The Mcm3 protein is imported into the nucleus by a specific NLS. The cell cycle specific nuclear accumulation of Mcm3 appears to be a result of nuclear retention or nuclear targeting, rather than nuclear import regulated through the NLS.
Replication profile of Saccharomyces cerevisiae chromosome VI
Authors: Friedman Katherine L. , Brewer Bonita J. , Fangman Walton L. 
Published: November 2003

Background:An understanding of the replication programme at the genome level will require the identification and characterization of origins of replication through large, contiguous regions of DNA. As a step toward this goal, origin efficiencies and replication times were determined for 10 ARSs spanning most of the 270 kilobase (kb) chromosome VI of Saccharomyces cerevisiae.Results:Chromosome VI shows a wide variation in the percentage of cell cycles in which different replication origins are utilized. Most of the origins are activated in only a fraction of cells, suggesting that the pattern of origin usage on chromosome VI varies greatly within the cell population. The replication times of fragments containing chromosome VI origins show a temporal pattern that has been recognized on other chromosomes—the telomeres replicate late in S phase, while the central region of the chromosome replicates early.Conclusions:As demonstrated here for chromosome VI, analysis of the direction of replication fork movement along a chromosome and determination of replication time by measuring a period of hemimethylation may provide an efficient means of surveying origin activity over large regions of the genome.
Far‐field characterization of small apertures
Authors: Petrov N. I. , Woo G. M. , Lee M. B. 
Published: November 2003

SummaryA far‐field method for characterizing apertures based on the relationship between the relative intensity of propagating modes in a given medium and a small aperture illuminated with a light beam is proposed. A simple optical set‐up based on computer‐generated holograms and spatial filters is suggested to measure the relative strength of modes and provide axial intensity measurements in the far‐field zone. It is shown that the minimal size of a spot that may be measured decreases with an increase in the refractive index of a medium into which light propagates and with the use of high‐order spatial mode filters. The intensities transmitted through tapered optical fibre tips have been measured and their aperture diameters determined using window‐type spatial filters. The results have been compared with measurements using scanning electron microscopy.
Image analysis of X‐ray microtomograms of soft materials during convective drying
Authors: Leonard A. , Blacher S. , Marchot P. , Pirard J. P. , Crine M. 
Published: November 2003

SummaryX‐ray microtomography is used to explore the textural evolution that soft materials undergo during a drying treatment. An original image processing algorithm is applied to vertical projections and reconstructed cross‐section images in order to quantify the texture at different stages of drying. Measurements are performed both on grey‐level and on binary images. It is shown that X‐ray microtomography is a very promising tool in the field of drying investigations. It can be used to determine internal moisture profiles, and to follow crack development and shrinkage in an accurate and non‐destructive way. This information is crucial to validate drying models. Waste‐water sludges are used as test materials to assess the validity of the proposed methodology. The management of these sludges, often including a drying stage, will become a challenge in the forthcoming years in accordance with environmental regulations. Samples collected in two waste‐water treatment plants are investigated. Their analysis by X‐ray microtomography brings to the fore two different drying behaviours, illustrating that sludge drying is a complex unit operation very sensitive to the way the material is produced.