bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prostaglandin E2 is a potent regulator of interleukin‐12‐ and interleukin‐18‐induced natural killer cell interferon‐γ synthesis
Authors: Walker William , Rotondo Dino 
Published: February 2004

SummarySynthesis of interferon (IFN)‐γ by natural killer (NK) cells is an important pro‐inflammatory event with interleukin (IL)‐12 and IL‐18 playing major inductive roles. However, other temporal events are likely to regulate such processes and as prostaglandin E2 (PGE2) is ubiquitous during inflammation this study tested the hypothesis that PGE2 was capable of directly modulating cytokine‐induced NK cell IFN‐γ synthesis in the absence of other immune cells. Using homogenous NK cell lines to establish direct effects, PGE2 (0·1–1 µm) was found to suppress NK cell IFN‐γ synthesis and antagonized the potent synergistic IFN‐γ‐inducing effects of IL‐12 and IL‐18. The actions of PGE2 were mimicked by synthetic PGE2 analogues including misoprostol and butaprost. The selective EP2 receptor agonist butaprost, but not the EP1/EP3 agonist sulprostone, suppressed IFN‐γ synthesis and exclusively competed with PGE2 for receptor binding on NK cells. Further analysis showed that PGE2 did not modulate IL‐12 receptor mRNA expression and the effects of PGE2 could be mimicked by the phosphodiesterase inhibitor 3‐iosobutyl‐1‐methylxanthine. The absence of demonstrable receptor modulation coupled with the observed suppression of IFN‐γ synthesis by both EP2 receptor‐selective agonists and IBMX suggest that PGE2 acts directly on NK cells via EP2 receptors with its downstream effects on cAMP metabolism. This conclusion is further supported by findings that PGE2 and its analogues consistently elevated levels of cAMP in NK cells. The ability of PGE2 to antagonize the potent inductive signal provided by the combination of IL‐12 and IL‐18 supports the concept that PGE2 may play an important role in limiting innate inflammatory processes in vivo through direct suppression of NK cell IFN‐γ synthesis.
Allelic distribution of human leucocyte antigen in historical and recently diagnosed tuberculosis patients in Southern Italy
Authors: Ruggiero Giuseppina , Cosentini Elena , Zanzi Delia , Sanna Veronica , Terrazzano Giuseppe , Matarese Giuseppe , Sanduzzi Alessandro , Perna Francesco , Zappacosta Serafino 
Published: February 2004

SummaryThis study addresses the analysis of the human leucocyte antigen (HLA) allele distribution in 54 historical and in 68 recently diagnosed tuberculosis (TB) patients. The historical cohort was characterized by the presence of large fibrocavernous lesions effectively treated with therapeutic pneumothorax during the period 1950–55. Patients and healthy controls enrolled in the study were from the Campania region of southern Italy. No significant association between HLA alleles and TB in the population of recently diagnosed TB patients was observed. On the contrary, among the historical TB patients there was a strong association with an increased frequency of the HLA‐DR4 allele alone and/or in the presence of the HLA‐B14 allele (P = 0·000004; Pc = 0·0008), as well as with a decreased frequency of the HLA‐A2+,‐B14−,DR4− allele association (P = 0·00005; Pc = 0·01). In order to exclude any interference from age‐related factors, these results were confirmed by comparing the historical cohort of TB patients with an age‐matched healthy control population of the same ethnic origin (P = 0·00004; Pc = 0·008; and P = 0·0001; and Pc = 0·02, respectively).
CD40 is required for the optimal induction of protective immunity to Mycobacterium avium
Authors: Flórido Manuela , Gonçalves Ana Sofia , Gomes M. Salomé , Appelberg Rui 
Published: February 2004

SummaryC57Bl/6 mice and mice deficient in the CD40 molecule were infected with three strains of Mycobacterium avium. Two of the M. avium strains proliferated more extensively in CD40‐deficient (CD40−/−) mice than in control mice. The increased susceptibility to infection of CD40−/− mice was associated with the generation of poorer interleukin‐12 (IL‐12) p40 and interferon‐γ (IFN‐γ) responses as compared to the controls, suggesting a role for CD40 in the development of protective immunity. In contrast, direct triggering of CD40 on infected macrophages failed to induce any anti‐mycobacterial activity in infected macrophages.
Restricted cytokine production from mouse peritoneal macrophages in culture in spite of extensive uptake of plasmid DNA
Authors: Yasuda Kei , Kawano Hiroki , Yamane Ikuko , Ogawa Yoshiyuki , Yoshinaga Takaharu , Nishikawa Makiya , Takakura Yoshinobu 
Published: February 2004

SummaryThe production of inflammatory cytokines from macrophages (Mφ), upon stimulation with plasmid DNA (pDNA) containing CpG motifs, is a critical process for DNA‐based therapies such as DNA vaccination and gene therapy. We compared Mφ activation, following stimulation with naked pDNA, based on the production of cytokines from cell lines (RAW264.7 and J774A1) and peritoneal Mφs in primary culture. The Mφ cell lines RAW264.7 and J774A1 produced a significant amount of tumour necrosis factor‐α (TNF‐α) upon stimulation with naked pDNA and this response required endosomal acidification. On the other hand, peritoneal Mφs (both resident and elicited) in primary culture did not secrete TNF‐α or interleukin‐6, although they contain the mRNA of toll‐like receptor‐9 (TLR‐9) and are able to respond to CpG oligodeoxynucleotides. This unresponsiveness was not a result of impaired cellular uptake of pDNA because the primary cultured Mφs showed a higher uptake of pDNA than the RAW264.7 and J774A1 cell lines. These findings have important implications for Mφ activation by naked pDNA as it has been generally assumed that pDNA that contains CpG motifs is a potent agent for inducing inflammatory cytokines in vivo, based on evidence from in vitro studies using Mφ cell lines.
Factors affecting the susceptibility of the mouse pituitary gland to CD8 T‐cell‐mediated autoimmunity
Authors: De Jersey James , Carmignac Danielle , Le Tissier Paul , Barthlott Thomas , Robinson Iain , Stockinger Brigitta 
Published: February 2004

SummaryWe have previously shown, in a transgenic mouse model, that the pituitary gland is susceptible to CD8 T‐cell‐mediated autoimmunity, triggered by a cell‐specific model autoantigen, resulting in pan‐anterior pituitary hypophysitis and dwarfism. In the present study, we now demonstrate that antigen dose, the T‐cell precursor frequency, the degree of lymphopenia and the context of target antigen expression, are important parameters determining the time course and extent of the pathological consequences of CD8 T‐cell‐mediated autoimmunity. Furthermore, our data indicate that the pituitary gland is susceptible to CD8 autoimmunity following an inflammatory insult such as a viral infection. As lymphocytic hypophysitis may be manifest in other autoimmune conditions, and the pituitary gland may be susceptible to T‐cell‐mediated pathology after immunization with a virus expressing soluble pituitary antigen, it is important to consider that strategies based on vaccination against soluble pituitary gonadotrophins could have other unexpected endocrine consequences.
A Versatile Birth—Death Model Applicable to Four Distinct Problems
Authors: Gani J. 
Published: February 2004

SummaryThis paper revisits a simple birth–death model which arises in slightly different forms in four distinct stochastic problems. These are the barbershop queue, coupon collecting, vocabulary usage and geological dating. Discrete and continuous time Markov chains are used to characterize these problems. Somewhat different questions are posed for each particular case, and practical results are derived for each process. The paper concludes with some comments on the versatility of this applied probability model.
The Distribution of Species Numbers in a Controlled Environment
Authors: Whittle Peter 
Published: February 2004

SummaryA model is proposed in which a population of projects is induced to distribute itself optimally over a number of modes (‘species’), consistently with resource constraints, by manipulation of a price vector. A control rule for the price vector is suggested which is shown by the use of a Liapunov function to achieve convergence to the optimum. For a stochastic version of the problem this Liapunov function has a distributional interpretation, leading to the conclusion that the numbers in the various surviving modes are distributed as independent gamma variables in an open model.
Asymptotics and Criticality for a Correlated Bernoulli Process
Authors: Heyde C.C. 
Published: February 2004

SummaryA generalized binomial distribution that was proposed by Drezner & Farnum in 1993 comes from a correlated Bernoulli process with interesting asymptotic properties which differ strikingly in the neighbourhood of a critical point. The basic asymptotics and a short‐range/long‐range dependence dichotomy are presented in this note.
Ultimate Extinction of the Promiscuous Bisexual Galton—Watson Metapopulation
Authors: Cornell Stephen J. , Isham Valerie S. 
Published: February 2004

SummaryA variant of a sexual Gallon–Watson process is considered. At each generation the population is partitioned among n‘hosts’ (population patches) and individual members mate at random only with others within the same host. This is appropriate for many macroparasite systems, and at low parasite loads it gives rise to a depressed rate of reproduction relative to an asexual system, due to the possibility that females are unmated. It is shown that stochasticity mitigates against this effect, so that for small initial populations the probability of ultimate extinction (the complement of an ‘epidemic’) displays a tradeoff as a function of n between the strength of fluctuations which overcome this ‘mating’ probability, and the probability of the subpopulation in one host being ‘rescued’ by that in another. Complementary approximations are developed for the extinction probability: an asymptotically exact approximation at large n, and for small n a short‐time probability that is exact in the limit where the mean number of offspring per parent is large.
Existence and Uniqueness of Q‐Processes with a Given Finite μ‐Invariant Measure
Authors: Pollett Phil , Zhang Hanjun 
Published: February 2004

SummaryLet Q be a stable and conservative Q‐matrix over a countable state space S consisting of an irreducible class C and a single absorbing state 0 that is accessible from C. Suppose that Q admits a finite μ‐subinvariant measure m on C. We derive necessary and sufficient conditions for there to exist a Q‐process for which m is μ‐invariant on C, as well as a necessary condition for the uniqueness of such a process.
Subexponential Distributions — Large Deviations with Applications to Insurance and Queueing Models
Authors: Baltrūnas Aleksandras , Klüppelberg Claudia 
Published: February 2004

SummaryThis paper presents a fine large‐deviations theory for heavy‐tailed distributions whose tails are heavier than exp(−√t and have finite second moment. Asymptotics for first passage times are derived. The results are applied to estimate the finite time ruin probabilities in insurance as well as the busy period in a GI/G/1 queueing model.
Long‐Range Dependence of Markov Renewal Processes
Authors: Vesilo R.A. 
Published: February 2004

SummaryThis paper examines long‐range dependence (LRD) and asymptotic properties of Markov renewal processes generalizing results of Daley for renewal processes. The Hurst index and discrepancy function, which is the difference between the expected number of arrivals in (0, t] given a point at 0 and the number of arrivals in (0, t] in the time stationary version, are examined in terms of the moment index. The moment index is the supremum of the set of r > 0 such that the rth moment of the first return time to a state is finite, employing the solidarity results of Sgibnev. The results are derived for irreducible, regular Markov renewal processes on countable state spaces. The paper also derives conditions to determine the moment index of the first return times in terms of the Markov renewal kernel distribution functions of the process.
Dismissing‐avoidant pattern of attachment and mimicry reactions at different levels of information processing
Authors: Sonnby‐Borgström Marianne , Jönsson Peter 
Published: February 2004

Sonnby‐Borgström, M. & Jönsson, P. (2004). Dismissing‐avoidant pattern of attachment and mimicry reactions at different levels of information processing. Scandinavian Journal of Psychology, 45, 103–113.Individuals with a dismissing‐avoidant pattern of attachment are assumed to repress anxiety‐related signals, a disposition hypothesized to interfere with facial mimicry and emotional contagion. Further, they are assumed to have one internal working model associated with anxiety, operating out of awareness at early, automatic stages of information processing, and another positive model operating at later, cognitively controlled stages of processing. The main aim of the present investigation was to compare facial mimicry in dismissing‐avoidant and non‐dismissing subjects at different levels of information processing. Pictures of happy and angry faces were exposed to 61 subjects at three different exposure times (17, 56, and 2,350 ms) in order to elicit facial muscle reactions, first at automatic levels and then at a more controlled levels. Corrugator activity (“frowning muscles”) represented negative emotions and zygomaticus activity (“smiling muscles”) positive emotions. The dismissing‐avoidant subjects scored significantly lower on emotional empathy than the non‐dismissing subjects. At the automatic level the dismissing‐avoidant subjects showed “normal” corrugator responses (negative emotions) upon exposure to angry faces. At the cognitively controlled level of processing (2,350 ms) a significant interaction effect was shown between Faces × Muscles × Attachment pattern. The dismissing‐avoidant subjects showed no corrugator response and an increased zygomaticus response (“smiling reaction”) to the angry face, whereas the non‐dismissing subjects reacted with a significant mimicking reaction. The dismissing‐avoidant subjects’ tendency to “smiling” in response to the angry face at the controlled level (2,350 ms) may be interpreted as a repression of their earlier, automatically evoked (56 ms) negative emotional reaction.
Relations between enabling skills and reading comprehension: A follow‐up study of Latvian students from first to second grade
Authors: Sprugevica Ieva , Høien Torleiv 
Published: February 2004

Sprugevica, I. & Høien, T. (2004). Relations between enabling skills and reading comprehension: A follow‐up study of Latvian students from first to second grade. Scandinavian Journal of Psychology, 45, 115–122.In order to examine the relationships among various phonological skills and reading comprehension, Latvian children were followed from grade 1 to grade 2 and were tested with a battery of phonological, word reading, and reading comprehension tasks. A principal component analysis of the phonological tasks revealed three salient factors: a phonemic awareness factor, a rapid naming factor, and a short‐term memory factor. In order to analyze the relationship between various phonological skills and reading comprehension, a structural modeling analysis was performed. Phonemic awareness and rapid naming explained approximately the same amount of unique variance in reading comprehension, but phonemic awareness had most predictive power indirectly via word decoding. Only rapid naming had a significant direct impact on reading comprehension.
Effects of age and anxiety on episodic memory: Selectivity and variability
Authors: Li Juan , Nilsson Lars‐Göran , Wu Zhenyun 
Published: February 2004

Li, J., Nilsson, L.‐G. & Wu, Z. (2004). Effects of age and anxiety on episodic memory: Selectivity and variability. Scandinavian Journal of Psychology, 45, 123–129.Selective age‐related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high‐ and low‐anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well‐known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age‐related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory.
Assessing Type A behavior in children: A longitudinal exploration of the overlap between Type A behavior and hyperactivity
Authors: Nyberg Lilianne , Bohlin Gunilla , Hagekull Berit 
Published: February 2004

Nyberg, L., Bohlin, G. & Hagekull, B. (2004). Assessing Type A behavior in children: A longitudinal exploration of the overlap between Type A behavior and hyperactivity. Scandinavian Journal of Psychology, 45, 145–156.Child Type A behavior and its relation to hyperactivity were investigated developmentally using a longitudinal normal sample of 91 children (46 boys and 45 girls) between the ages of 4 and 8–9. In light of the overlap found in several studies between Type A behavior, as measured by the Matthews Youth Test for Health (MYTH) questionnaire, and hyperactivity measured by questionnaires, an attempt was made to measure Type A behavior as distinct from hyperactivity using behavioral observations. The MYTH questionnaire and behavioral observations were used to assess Type A behavior and questionnaire‐based measures and behavioral observations were used to assess hyperactivity. Predictions were made regarding individual stability in phenomena and in measures. The results indicated considerable stability in the respective Type A and hyperactivity measures over time, and further, that behavioral observations make it possible to measure Global Type A behavior and Type A Competitiveness as distinct from hyperactivity, although the status of Type A Impatience at early ages is not yet settled. The MYTH and the observed Type A behavior showed differential relations to external criteria, such as achievement measures and problem behavior. This has implications for future measurement and perhaps conceptualization of Type A behavior in children, and thereby also for studying the developmental aspects of Type A behavior.
Development of clinical guidelines for prone positioning in critically ill adults
Authors: Rowe Catherine 
Published: February 2004

Summary• Literature reveals evidence that prone positioning can improve the oxygenation of critically ill patients suffering from acute lung injury or acute respiratory distress syndrome• Multicentre evidence, however, does not support the claim that it improves patients' outcome• The implementation of multiprofessional guidelines by which to direct the manoeuvre will facilitate the safe and effective management of patients in the prone position. They will thus heighten multiprofessional awareness of the technique and promote its proactive use at such time so as to achieve maximum clinical benefit
Effect of employee worktime control on health: a prospective cohort study
Authors: Ala-Mursula L , Vahtera J , Pentti J , Kivimäki M 
Published: February 2004

Aims:To investigate the health effects of employee worktime control.Methods:Prospective cohort study among 4218 permanent full time municipal employees linking questionnaire data from 1997 and 2000 with sickness absence records from 1997 and 2001. Worktime control was considered high for the highest tertile in both 1997 and 2000, low for the lowest tertile for both years, and intermediate for all other combinations. Self rated health status, psychological distress, and medically certified periods of sickness absence were used as the health outcomes. Adjustments were made for age, baseline health status, occupational status, marital status, dependent children, and behavioural health risks.Results:In the follow up, women with a low level of worktime control had a 1.9 times (95% CI 1.4 to 2.5) higher odds ratio for poor self rated health, a 1.4 times (95% CI 1.1 to 1.8) higher odds ratio for psychological distress, and a 1.5 times (95% CI 1.3 to 1.7) higher risk of medically certified sickness absences than women with a high level of worktime control. The health effects of worktime control were particularly evident among women with families. Among men, worktime control was not associated with self rated health or distress, but it predicted sickness absences in two subgroups: those with dependent children and those with manual occupations.Conclusions:A low level of worktime control increases the risk of future health problems. The risk is highest among women, especially those with families, and among manual workers. The results suggest that worktime control can help workers integrate their work and private lives successfully.
Association between urinary 1-hydroxypyrene and genotoxic effects in coke oven workers
Authors: Siwińska E , Mielżyńska D , Kapka L 
Published: February 2004

Aims:To investigate whether current occupational exposure of coke oven workers to polycyclic aromatic hydrocarbons (PAHs) results in genotoxic effects measured in peripheral blood lymphocytes and whether these biomarkers are associated with the biomarkers of exposure.Methods:Blood and urine samples were collected immediately after a shift at the end of a working week from 50 coke oven workers and 50 control workers not exposed to PAHs. Methods included: (1) biomarkers of exposure: urinary 1-hydroxypyrene (HpU), urinary mutagenicity by the plate Salmonella test with strains TA98 and YG1024 after metabolic activation, expressed as mutagenic rate (MR98 and MR1024, respectively), urinary cotinine; and (2) biomarkers of biological effects in peripheral blood lymphocytes (PBL): sister chromatid exchanges (SCE/cell), cells of high frequency of SCE (% HFC), micronuclei (MN/1000 cells), chromosomal aberrations (CA/100 cells), and DNA damage by the Comet assay.Results:Occupational exposure to PAH resulted in significantly increased levels of HpU and mutagenic effect of urine. Median values of these biomarkers in coke oven workers were: 9.0 μmol/mol creatinine for HpU, 2.7 for MR98, and 8.2 for MR1024, compared to the controls: HpU = 0.6 μmol/mol creatinine, MR98 = 1.2, and MR1024 = 5.5. Occupational exposure caused significant induction of SCE, HFC, and MN in coke oven workers: median SCE = 5.9, HFC = 12.0%, MN = 6.0 compared to the controls: 3.9, 5.0%, and 3.0, respectively. No effect of occupational exposure was found in relation to CA and DNA damage measured with the Comet assay. HpU concentration was positively associated with SCE and HFC. The concentration of urinary 1-hydroxypyrene corresponding to a 5% probability of increased SCE was 1.0 μmol/mol creatinine.Conclusions:The occupational exposure to PAHs resulted in measurable biological effects (SCE, HFC, MN). In coke oven workers an increased level of SCE was not observed below the level of 1.0 μmol HpU/mol creatinine.