bluuebunny/crossref_metadata_2025_split huggingface dataset:
Systemic effects of oral tolerance on inflammation: mobilization of lymphocytes and bone marrow eosinopoiesis
Authors: Rodrigues Claudiney M. , Martins‐Filho Olindo A. , Vaz Nelson M. , Carvalho Cláudia R. 
Published: February 2006

SummaryOral tolerance is a T‐cell mediated phenomenon defined by inhibition of immune responsiveness to a protein previously contacted by the oral route. Oral tolerance may prevent autoimmune and allergic diseases that involve the recruitment and/or activation of different cell types including mast cells, neutrophils, eosinophils, monocytes and lymphocytes. The mechanisms by which oral tolerance avoids these immunological disorders are still controversial. Herein we used a murine model of ovalbumin (OVA)‐induced peritonitis to investigate the effect of oral tolerance on allergic inflammation. Frequency of leucocyte subpopulations was evaluated by global and differential cell counts in peritoneal lavage fluid, peripheral blood, and bone marrow. Changes on lymphocyte subsets and adhesion molecules expression by these cells were analysed by flow cytometry. As compared with OVA‐immune mice, intraperitoneal challenge of tolerant animals with OVA resulted in a significantly milder peritonitis, mostly affecting neutrophils and eosinophils; a concomitant reduction in total white blood cell counts was also observed, mainly because of lower neutrophil and eosinophil counts. Eosinophils, but not neutrophils, were also reduced in the bone‐marrow of OVA‐challenged tolerant mice. No changes occurred in total peritoneal lymphocyte counts in OVA‐tolerant mice, however, there was a significant decrease in CD3+ CD8+ T cells and an increase in B cells (CD45R+) in these animals as compared to immune OVA‐challenged animals. Altered expression of CD18 and CD54, respectively, in blood and peritoneal lymphocytes was also noted. These results suggest that, in addition to local specific effects, oral tolerance has systemic effects on the mobilization of leucocytes and bone‐marrow eosinopoiesis.
Identification of a major histocompatibility complex class I‐restricted T‐cell epitope in the tumour‐associated antigen, 5T4
Authors: Redchenko Irina , Harrop Richard , Ryan Matthew G. , Hawkins Robert E. , Carroll Miles W. 
Published: February 2006

Summary5T4 is a surface glycoprotein expressed on placental trophoblasts and also on a wide range of human carcinomas. Its highly restricted expression on normal tissues and broad distribution on many carcinomas make 5T4 a promising target for cancer immunotherapy. In the current study, we set out to investigate whether a 5T4‐specific cytotoxic T lymphocyte (CTL) repertoire exists in healthy individuals. CD4‐depleted peripheral blood mononuclear cells (PBMCs) from blood donors were screened using an ex vivo interferon‐γ (IFN‐γ) enzyme‐linked immunospot (ELISPOT) assay. A panel of overlapping peptides, spanning the full length of the 5T4 protein, was used as a source of antigen. In the process of screening, one out of 30 blood donors demonstrated a positive ex vivo IFN‐γ ELISPOT response to a single 5T4 peptide. A polyclonal T‐cell line was derived from this donor by culturing PBMCs with autologous peptide‐pulsed dendritic cells (DCs). The resulting polyclonal T‐cell line and clones were tested in a 51Cr‐release assay and by ELISPOT and were shown to be peptide specific. Furthermore, antigen‐presenting cells (APCs), infected with a viral vector expressing 5T4, were able to stimulate IFN‐γ production by the peptide‐specific T‐cell clones. A minimal CD8 epitope, PLADLSPFA, has been identified and found to be restricted through human leucocyte antigen (HLA) Cw7. Subsequently, we have demonstrated that HLA‐Cw7‐positive colorectal cancer patients vaccinated with a recombinant vaccinia viral vector encoding 5T4 (TroVax) are capable of mounting a strong IFN‐γ ELISPOT response to this novel CTL epitope. These findings have potential application in cancer immunotherapy in terms of subunit vaccine design and the monitoring of immune responses induced in patients by 5T4‐based therapies.
Significant impact of 5α‐reductase type 2 polymorphisms on sperm concentration and motility
Authors: Elzanaty S. , Giwercman Y. L. , Giwercman A. 
Published: February 2006

SummaryAndrogens, including 5α‐dihydrotestosterone (DHT), are known to play a role for spermatogenesis and accessory sex gland function. The enzyme 5α‐reductase (SRD5A) catalyses the conversion of testosterone to DHT. Our objective was to investigate whether polymorphisms in the SRD5A2 gene influence semen parameters in the general population. DNA from 182 Swedish military conscripts was examined for the A49T, V89L, and R227Q polymorphisms in the SRD5A type 2 gene. Ejaculates were analysed according to WHO guidelines. In addition, sperm motility was assessed using computer‐aided sperm analysis (CASA). Seminal markers of epididymal (neutral α‐glucosidase), prostatic (prostate specific‐antigen and zinc), and seminal vesicles function (fructose) were measured. The A49TT‐allele was associated with significantly higher sperm concentration compared with the wild type A‐allele (mean: 102 × 106/mL vs. 57 × 106/mL, p = 0.02). The V89LV‐genotype was correlated with significantly higher proportion progressive motile spermatozoa compared with the L‐variant (mean: 55% vs. 48%, p = 0.04). The same trend was found regarding the CASA motile spermatozoa (mean: 52% vs. 41%, p = 0.02). No association between any of the polymorphisms and biochemical markers was found. SRD5A2 gene variants were associated with sperm concentration and motility, but not with epididymal and accessory sex gland markers. This effect on sperm parameters might therefore be exerted via a direct effect of DHT on spermatogenesis.
Chronic partial sleep loss increases the facilitatory role of a masked prime in a word recognition task
Authors: SWANN CLAIRE E. , YELLAND GREG W. , REDMAN JENNIFER R. , RAJARATNAM SHANTHA M. W. 
Published: February 2006

SummaryNeurobehavioural performance deficits associated with sleep loss have been extensively studied, in particular, the effects on psychomotor performance. However, there is no consensus as to which, if any, cognitive functions are impaired by sleep loss. To examine how sleep loss might affect cognition, the automatic processes supporting word recognition were examined using the masked priming paradigm in participants who had been exposed to two consecutive days of sleep restriction. Twelve healthy volunteers (mean age 24.5 years) were recruited. Nocturnal sleep duration was restricted to 60% of each participant's habitual sleep duration for two consecutive nights by delaying scheduled time of sleep onset and advancing time of awakening. In controlled laboratory conditions, participants completed the Psychomotor Vigilance Task and Karolinska Sleepiness Scale and a masked priming word recognition task. As expected, significant increases in subjective sleepiness and impaired psychomotor performance were observed after sleep loss. In contrast, response times and error rate on the masked priming task were not significantly affected. However, the magnitude of the masked priming effect, which can be taken as an index of automaticity of lexical processing, increased following sleep loss. These findings suggest that while no evidence of impairment to lexical access was observed after sleep loss, an increase in automatic processing may occur as a consequence of compensatory mechanisms.
Bladder voiding in sleeping infants is consistently accompanied by a cortical arousal
Authors: ZOTTER HEINZ , SAUSENG WERNER , KUTSCHERA JOERG , MUELLER WILHELM , KERBL REINHOLD 
Published: February 2006

SummaryThe aim of the study was to find out whether bladder voiding in healthy sleeping infants was accompanied by any arousal reaction. Polygraphic recordings were performed in 21 healthy infants (11 female) born at term. The infants’ age at study entry was 42 ± 4 days and actual body weight was 4852 ± 689 g (mean ± SD). Bladder voiding was recorded by an adapted enuresis detector which was connected to the polygraphic computer unit. Arousals were defined as suggested by the ‘International Paediatric Work Group on Arousals’. Awakenings were excluded from the study. Bladder voiding was recorded at a mean time of 68 ± 7 min after the infant had fallen asleep and occurred during quiet sleep (QS). Electroencephalogram frequency (P < 0.01) and heart rate (P < 0.05) were higher during the 5‐s period before and after bladder voiding when compared with a 30‐s interval before voiding. Furthermore, bladder voiding was accompanied by body movements in all infants. Respiratory frequency did not change significantly. We could demonstrate for the first time in sleeping infants, that bladder voiding during QS was accompanied by a cortical arousal.
Nocturnal sustained attention during sleep deprivation can be predicted by specific periods of subjective daytime alertness in normal young humans
Authors: TAILLARD JACQUES , MOORE NICHOLAS , CLAUSTRAT BRUNO , COSTE OLIVIER , BIOULAC BERNARD , PHILIP PIERRE 
Published: February 2006

SummaryIn our 24‐h society, nocturnal sleep‐related accidents are common. Because all individuals are not equal in their responses to sleep loss, it is very important to identify predictors of vulnerability to sleep deprivation in normal subjects. We investigated the performance of a cognitive test of sustained attention, electroencephalogram theta/alpha power, subjective sleepiness, and two circadian markers (core temperature and melatonin) in 18 healthy men (nine morning types and nine evening types, 21.4 ± 1.9 years) during a 36‐h sleep deprivation in a constant routine protocol. Sleep need (self‐reported) and baseline sleep structure were also investigated. Nighttime performance impairment was defined as the difference between the mean nocturnal number of lapses (00:00–19:30 hours) and the mean diurnal number of lapses (07:30–20:30 hours) expressed as a percentage. Feeling fully alert in the morning just after awakening and/or sleepy in early afternoon were the only two factors (Multiple R > 0.80, >60% of explained variance) which better predicted the decrease in performances of nocturnal operational tasks requiring sustained attention.
A novel high‐affinity arginine transporter from the human parasitic protozoan Leishmania donovani
Authors: Shaked‐Mishan Pninit , Suter‐Grotemeyer Marianne , Yoel‐Almagor Tamar , Holland Neta , Zilberstein Dan , Rentsch Doris 
Published: February 2006

SummaryWe describe the first functional and molecular characterization of an amino acid permease (LdAAP3) from the human parasitic protozoan Leishmania donovani, the causative agent of visceral leishmaniasis in humans. This permease contains 480 amino acids with 11 predicted trans‐membrane domains. Expressing LdAAP3 in Saccharomyces cerevisiae mutants revealed that LdAAP3 codes for a high‐affinity arginine transporter (Km 1.9 µM). LdAAP3 is highly specific for arginine as its transport was not inhibited by other amino acids or arginine‐related compounds. Using green fluorescence protein (GFP) fused to the N‐terminus of LdAAP3, this transporter was localized to the surface membrane of promastigotes. The GFP–LdAAP3 chimera mediated a threefold increase in arginine transport in promastigotes, indicating that it is active and confirmed that LdAAP3 codes for an arginine transporter in parasite cells as well. LdAAP3 is novel as it shares a high level of homology with amino acid permeases from other trypanosomatidae but almost none with permeases from other phyla. The results of this work suggest that LdAAP3 might play a role in host–parasite interaction.
The PmrA/PmrB and RcsC/YojN/RcsB systems control expression of the Salmonella O‐antigen chain length determinant
Authors: Delgado Mónica A. , Mouslim Chakib , Groisman Eduardo A. 
Published: February 2006

SummaryThe lipopolysaccharide (LPS) is the outermost component of the cell envelope in Gram‐negative bacteria. It consists of the hydrophobic lipid A, a short non‐repeating core oligosaccharide and a distal polysaccharide termed O‐antigen. We report here that the PmrA/PmrB and RcsC/YojN/RcsB two‐component systems of Salmonella enterica serovar Typhimurium independently promote transcription of the wzzst gene, which encodes a protein that determines the chain length of the O‐antigen. We show that the regulatory proteins PmrA and RcsB footprint partially overlapping regions of the wzzst promoter stimulating transcription from the same start site. Induction of the PmrA/PmrB or RcsC/YojN/RcsB systems increased the fraction of LPS molecules containing 16–35 O‐antigen subunits, leading to heightened resistance to serum. The LPS of a rcsB null mutant exhibited an altered mobility in the O‐antigen subunits attached to the lipid A‐core region when separated on a SDS/PAGE gel, suggesting that RcsB may regulate additional LPS genes. Inactivation of the wzzst gene eliminated the enhanced swarming behaviour exhibited by the rcsB mutant. That multiple regulatory systems control wzzst expression suggests that the Wzzst protein is required under different environmental conditions.
Characterization of a unique type IA topoisomerase in Bacillus cereus
Authors: Li Zhiyu , Hiasa Hiroshi , DiGate Russell 
Published: February 2006

Summary Bacillus cereus topoisomerase IIIβ (bcTopo IIIβ) has been cloned, overexpressed and biochemically characterized. This enzyme exhibits 64% and 33% sequence identity to Bacillus subtilis topoisomerase III (bsTopo III) and Escherichia coli topoisomerase III (ecTopo III) respectively. The enzymatic properties of bcTopo IIIβ differ substantially from other bacterial type IA topoisomerases, including E. coli type IA topoisomerases and B. cereus topoisomerase I (bcTopo I) and IIIα (bcTopo IIIα). bcTopo IIIβ only partially relaxes negatively supercoiled DNA and appears incapable of generating fully relaxed topoisomers. In contrast to ecTopo III and bcTopo IIIα, bcTopo IIIβ is not a decatenase. bcTopo IIIβ is unable to compensate the loss of ecTopo III in vivo. Therefore, bcTopo IIIβ is a unique prokaryotic type IA topoisomerase that is different from previously characterized topoisomerases.
NBU1 integrase: evidence for an altered recombination mechanism
Authors: Schmidt John W. , Rajeev Lara , Salyers Abigail A. , Gardner Jeffrey F. 
Published: February 2006

SummaryNBU1 is a 10.3 kbp Bacteroides mobilizable transposon. A previous study had identified a 2.7 kbp segment of the excised circular intermediate that was sufficient to mediate integration of the element after transfer. This segment contained an integrase gene, intN1, and a region spanning the ends of the circular form within which integration occurred (attN1). The integrase protein, IntN1, appeared to be a member of the tyrosine recombinase family because it contains the canonical C‐terminal RKHRHY [RK(H/K)R(H/W)Y] motif that characterizes members of that family. In this study, we describe an Escherichia coli‐based integration assay system that has allowed us to characterize attN1 in detail. We first localized attN1 to a 250 bp region. We then used site‐directed mutations to identify directly repeated sequences within attN1 that were required for site‐specific integration. The locus of NBU1 site‐specific integration in the Bacteroides thetaiotaomicron chromosome, attBT1‐1, contains a 14 bp sequence that is identical to a 14 bp sequence that spans the joined ends of the NBU1 attN1 site (common core sequences). The effects of mutations in the common core were different from the expected results if NBU1 integration was similar to λ integration. In particular single base changes near one end of the common core region, which introduced heterology, actually increased the frequency of integration. By contrast, compensating changes that restored homology in the common core region reduced the integration frequency. The recombination mechanism also differs from the one used by conjugative transposons that have coupling sequences between the sites of strand cleavage and exchange. These results indicate that although NBU1 integrase is considered to be a member of the tyrosine recombinase family, it catalyses an integrative recombination reaction that occurs by a different crossover mechanism.
Ribosomal protein L11 mutations in two functional domains equally affect release factors 1 and 2 activity
Authors: Sato Hanae , Ito Koichi , Nakamura Yoshikazu 
Published: February 2006

SummaryBacterial release factors (RFs) 1 and 2 catalyse translation termination at UAG/UAA and UGA/UAA stop codons respectively. It has been shown that limiting the amount of ribosomal protein L11 affects translation termination at UAG and UGA differently. To understand the functional interplay between L11 and RF1/RF2, we isolated 21 distinct mutations in L11 as suppressors of either temperature‐sensitive (ts) RF1/RF2 strains or read‐through mutants of lacZ nonsense (UAG or UGA) strains. 10 of 21 mutants restored ts lethal growth of RF1 and/or RF2 strains. All the selected L11 mutants, including the RF1ts‐ and RF2ts‐specific suppressors, had the same effect, either enhancing or reducing, on UAG and UGA termination efficiency in vivo. The specific properties of the selected L11 mutations remained unchanged in an RF3 deletion strain. Moreover, ribosomes absent of L11 had equally reduced activity for both RF1‐ and RF2‐mediated peptide release in vitro. These results suggest that, unlike the previous notion, L11 has a common, cooperative role with RF1 and RF2. These L11 mutations were located on the surface of two domains of L11, and interpreted to affect the interaction between L11 and rRNA or the RFs thereby leading to the altered translation termination.
First estimates of the fundamental parameters of the relatively bright Galactic open cluster NGC 5288
Authors: Piatti Andrés E. , Clariá Juan J. , Ahumada Andrea V. 
Published: February 2006

Abstract
In this paper we present charge-coupled device (CCD) images in the Johnson B and V and Kron—Cousins I passbands for the previously unstudied open cluster NGC 5288. The sample consists of 15 688 stars reaching down to V∼ 20.5. The cluster appears to have a relatively small but conspicuous nucleus and a low-density extended coronal region. Star counts carried out in 25 × 25 pixel2 boxes distributed throughout the whole observed field allowed us to estimate the angular core and corona radii as∼1.3 and 6.3 arcmin, respectively. Our analysis suggests that NGC 5288 is moderately young and probably more metal-rich than the Sun. Adopting the theoretical metal content Z= 0.040, which provides the best global fit, we derive an age of 130+40−30 Myr. Simultaneously, we have obtained colour excesses E(B-V) = 0.75 and E(V-I) = 0.95 and an apparent distance modulus V-MV= 14.00. The law of interstellar extinction in the cluster direction is found to be normal. NGC 5288 is located at 2.1 ± 0.3 kpc from the Sun beyond the Carina spiral feature and∼7.4 kpc from the Galactic Centre. The cluster metallicity seems to be compatible with the cluster position in the Galaxy, given the recognized radial abundance gradient in the disc. For the first time, in this paper we determine the basic parameters for the open cluster NGC 5381, situated in the same direction as NGC 5288. This determination was reached by using CCD VI data published almost a decade ago by Pietrzyński et al. (1997) for NGC 5381. The properties of some open clusters aligned along the line of sight of NGC 5288 are examined. The properties of clusters of similar ages to NGC 5288 are also looked into. Evidence is presented that these did not form mainly along the spiral arms but rather in the thin Galactic disc (Z∼±100 pc).
Over‐expression of different aldehyde dehydrogenase genes in Arabidopsis thaliana confers tolerance to abiotic stress and protects plants against lipid peroxidation and oxidative stress
Authors: KOTCHONI SIMEON O. , KUHNS CHRISTINE , DITZER ANDREA , KIRCH HANS‐HUBERT , BARTELS DOROTHEA 
Published: February 2006

ABSTRACTAldehyde dehydrogenases (ALDHs) play a major role in the detoxification processes of aldehydes generated in plants when exposed to abiotic stress. In previous studies, we have shown that the Arabidopsis thaliana ALDH3I1 gene is transcriptionally activated by abiotic stress, and over‐expression of the ALDH3I1 gene confers stress tolerance in transgenic plants. The A. thaliana genome contains 14 ALDH genes expressed in different sub‐cellular compartments and are presumably involved in different reactions. The purpose of this study was to compare the potential of a cytoplasmic and a chloroplastic stress‐inducible ALDH in conferring stress tolerance under different conditions. We demonstrated that constitutive or stress‐inducible expression of both the chloroplastic ALDH3I1 and the cytoplasmic ALDH7B4 confers tolerance to osmotic and oxidative stress. Stress tolerance in transgenic plants is accompanied by a reduction of H2O2 and malondialdehyde (MDA) derived from cellular lipid peroxidation. Involvement of ALDHs in stress tolerance was corroborated by the analysis of ALDH3I1 and ALDH7B4 T‐DNA knockout (KO) mutants. Both mutant lines exhibited higher sensitivity to dehydration and salt than wild‐type (WT) plants. The results indicate that ALDH3I1 and ALDH7B4 not only function as aldehyde‐detoxifying enzymes, but also as efficient reactive oxygen species (ROS) scavengers and lipid peroxidation‐inhibiting enzymes. The potential of ALDHs to interfere with H2O2 was also shown for recombinant bacterial proteins.
Predicting the clinical outcome of tetanus: the tetanus severity score
Authors: Thwaites C. L. , Yen L. M. , Glover C. , Tuan P. Q. , Nga N. T. N. , Parry J. , Loan H. T. , Bethell D. , Day N. P. J. , White N. J. , Soni N. , Farrar J. J. 
Published: February 2006

SummaryObjectives  To create a new tetanus score and compare it with the Phillips and Dakar scores.Methods  We used prospectively acquired data from consecutive patients admitted to the Hospital for Tropical Diseases, Ho Chi Minh City, to create the Tetanus Severity Score (TSS) with multivariate logistic regression. We compared the new score with Phillips and Dakar scores by means of resubstituted and prospective data, assessing performance in terms of sensitivity, specificity and area under receiver operator characteristic curves.Results  Resubstitution testing yielded a sensitivity of 77% (298/385) and a specificity of 82% (1183/1437) for the TSS; 89% (342/385) and 20% (281/1437) for the Phillips score; and 13% (49/385) and 98% (1415/1437) for the Dakar score. The TSS showed greatest discrimination with 0.89 area under the receiver operator characteristic curve (95% CI 0.88–0.90); this was 0.74 for the Dakar score and (95% CI 0.71–0.77) and 0.66 for the Phillips score (95% CI 0.63–0.70; P values <0.001). Prospective testing showed 65% (13/20) sensitivity and 91% (210/230) specificity for the TSS; 80% (16/20) and 51% (118/230) for the Phillips score; and 25% (5/20) and 96% (221/230) for the Dakar score. The TSS achieved the greatest area under TSS of 0.89 (95% CI 0.82–0.96), significantly greater than the Phillips score [0.74 (0.6–0.88), P = 0.049] but not the Dakar score [0.80, (0.71–0.90), P = 0.090].Conclusions  The TSS is the first prospectively developed classification scheme for tetanus and should be adopted to aid clinical triage and management and as a basis for clinical research.