bluuebunny/crossref_metadata_2025_split huggingface dataset:
An association between plastic mattress covers and sheepskin underbedding use in infancy and house dust mite sensitization in childhood: a prospective study
Authors: Trevillian L. F. , Ponsonby A.‐L. , Dwyer T. , Lim L. L.‐Y. , Kemp A. , Cochrane J. , Carmichael A. 
Published: December 2004

SummaryBackground Higher house dust mite (HDM) allergen exposure during infancy has been associated with increased HDM sensitization. Infant bedding has been associated with the accumulation of varying levels of HDM. Prospective data on the relationship between infant bedding and the development of HDM sensitization has not been previously examined.Objectives To determine if particular types of bedding used in infancy are associated with increased risk of house dust mite sensitization in childhood.Methods A population‐based sample (n = 498) of children born in 1988 or 1989, and who were resident in Northern Tasmania in 1997, participated in this study. These children were part of a birth cohort study (1988–95), the Tasmanian Infant Health Survey. Data on infant underbedding and mattresses was available on 460 and 457 children, respectively. The main outcome measure was HDM sensitization defined as a skin prick test (SPT) reaction of 3 mm or more to the allergens of Dermatophagoides pteronyssinus and/or Dermatophagoides farinae.Results The use of either sheepskin underbedding or plastic mattress covers in infancy was associated with an increased risk of sensitization to HDM allergens at age 8 years. The adjusted risk ratio (RR) for sensitization to HDM with sheepskin in infancy was 2.27 (95% CI: 1.14, 4.55), P = 0.020. The adjusted RR for sensitization to HDM with the use of plastic mattress covers in infancy was 2.06 (95% CI: 1.22, 3.51), P = 0.007. The use of a foam mattress in infancy was not related to subsequent HDM sensitization.Conclusion Infant's bedding plays a role in the development of HDM sensitization in childhood. Intervention studies to examine mite allergen levels and the role of underbedding on the development of HDM sensitization are required.
CTLA-4 (CD152) expression in peripheral blood T cells in Kawasaki disease
Authors: MATSUBARA T , ANWAR R , FUJIWARA M , ICHIYAMA T , FURUKAWA S 
Published: December 2004

SUMMARYKawasaki disease (KD) is an acute febrile illness of early childhood caused by vasculitis. Whether or not peripheral blood T cells are activated in acute KD remains uncertain, as some reports have presented evidence of peripheral blood T cell activation, whereas others suggest that the level of peripheral blood T cell activation is low during acute KD. Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4, CD152) is a surface molecule of activated T cells. We therefore investigated intracellular CTLA-4 expression in the peripheral blood T cells of patients with acute KD as a marker of T cell activation. We collected blood samples from 20 patients with KD and six with Epstein–Barr virus infectious mononucleosis (EBV-IM) who were admitted to our hospital, as well as 13 healthy children. We determined the intracellular expression of CTLA-4 in T cells by flow cytometry. We demonstrated that the intracellular expression of CTLA-4 is up-regulated in peripheral blood CD3+ T cells, CD4+ T cells and CD8+ T cells at the early part of the acute stage in KD. However, the mean percentages of intracellular T cells expressing CTLA-4 in EBV-IM patients were about fourfold higher than those in T cells from patients with acute KD. Our results suggested that the level of activation of peripheral blood T cells is very low during acute KD.
Production of antineutrophil cytoplasm antibodies derived from circulating B cells in patients with systemic vasculitis
Authors: CLAYTON A R , SAVAGE C O S 
Published: December 2004

SUMMARYThe pathogenesis of systemic vasculitis is complex and is likely to involve many mechanisms. In certain systemic vasculitides, autoimmunity plays an important role with autoantibodies developing towards neutrophils, which are termed antineutrophil cytoplasm antibodies (ANCA). There is a growing body of evidence that T cells may contribute to the pathogenesis of ANCA-associated vasculitides. A system was set up to determine whether B cells require T cell help to produce antibodies in a peripheral blood lymphocyte (PBL) culture system enriched for B cells and dendritic cells (DC). As a control, tetanus toxoid (TT) antibody production was detected from individuals not recently immunized with tetanus vaccine when stimulated with TT antigen. Proteinase 3 (PR3) and myeloperoxidase (MPO) antibodies were produced from B cell and DC enriched cultures prior to the addition of antigen in some ANCA-positive patients with high ANCA titres, but not from patients with low ANCA titres or controls. PBMC from individuals recently immunized with tetanus vaccine were also maximally stimulated in that addition of antibody did not enhance antibody production. We conclude that this system supports a role for T cell help in the production of TT antibodies in individuals not immunized recently with tetanus vaccine. However, in patients with ANCA-associated vasculitis and controls recently immunized with tetanus vaccine, circulating B cells are apparently spontaneously producing autoantibody, possibly reflecting a system already maximally driven in vivo, and therefore masking underlying potential T cell-B cell collaboration. Such B cells may be less responsive to regulatory stimuli in vivo.
Age-related accumulation of Ig VH gene somatic mutations in peripheral B cells from aged humans
Authors: CHONG Y , IKEMATSU H , YAMAJI K , NISHIMURA M , KASHIWAGI S , HAYASHI J 
Published: December 2004

SUMMARYTo investigate age-related alterations in human humoral immunity, we analysed Ig heavy chain variable region genes expressed by peripheral B cells from young and aged individuals. Three hundred and twenty-seven cDNA sequences, 163 µ and 164 γ transcripts with VH5 family genes, were analysed for somatic hypermutation and VHDJH recombinational features. Unmutated and mutated µ transcripts were interpreted as being from naive and memory IgM B cells, respectively. In young and aged individuals, the percentages of naive IgM among total µ transcripts were 39% and 42%, respectively. D and JH segment usage in naive IgM from aged individuals was similar to that from young individuals. The mutational frequencies of memory IgM were similar in young and aged individuals. γ transcripts, which are regarded as being from memory IgG B cells, showed a significantly higher mutational frequency (7·6%) in aged than in young individuals (5·8%) (P &lt; 0·01). These findings suggest that VHDJH recombinational diversity was preserved, but that the accumulation of somatic mutations in the IgG VH region was increased in aged humans. The accumulation of somatic mutations in IgG B cells during ageing may imply that an age-related alteration exists in the selection and/or maintenance of peripheral memory B cells.
Molecular cloning of feline tumour necrosis factor receptor type I (TNFR I) and expression of TNFR I and TNFR II in lymphoid cells in cats
Authors: Mizuno T. , Goto Y. , Baba K. , Masuda K. , Ohno K. , Tsujimoto H. 
Published: December 2004

SummaryTumour necrosis factor (TNF)‐α is a pro‐inflammatory cytokine produced by many types of cells. It has been shown that two distinct TNF receptors (TNFRs), TNFR type I (TNFR I) and TNFR type II (TNFR II), have different functions in signal transduction, which is possibly associated with the development of a variety of diseases. In this study, we isolated a feline TNFR I cDNA clone and analysed the expression of TNFR I and TNFR II mRNA in feline lymphoid cells. The deduced amino acid sequence of feline TNFRI cDNA showed 75.8, 62.5 60.9 and 72.1% similarity with those of its human, mouse, rat, and pig counterparts, respectively. The feline TNFR I cDNA was shown to encode extracellular, transmembrane and intracellular domains fundamentally conserved in the homologues of other species. Expression of TNFR I and TNFR II mRNAs was shown to be up‐regulated in feline peripheral blood mononuclear cells (PBMC) by stimulation with concanavalin A. Five of six feline lymphoma cell lines were shown to express both TNFR I and TNFR II mRNAs. The expression of TNFR I in PBMC was up‐regulated in cats infected with feline immunodeficiency virus (FIV), whereas the expression of TNFR II in PBMC was not different between FIV‐infected cats and uninfected cats. The present study indicate that expression of TNFR I and TNFR II may be associated with disease progression, especially in retrovirus infections in cats.
Relative quantification of HLA‐DRA1 and ‐DQA1 expression by real‐time reverse transcriptase–polymerase chain reaction (RT–PCR)
Authors: Fernandez S. , Wassmuth R. , Knerr I. , Frank C. , Haas J. P. 
Published: December 2004

SummaryPolymorphism in the upstream regulatory region (URR) of the MHC class II DQA1 gene defines 10 different alleles named QAP (DQA1 promoter). In vitro studies have suggested that allelic polymorphism in the HLA‐DQA promoter region may result in differences in HLA‐DQA1 gene expression. In the present study, we used real‐time reverse transcriptase–polymerase chain reaction (RT–PCR) to quantify differences in HLA‐DQA1 gene expression. After the isolation of total mRNA, reverse transcription into cDNA was carried out using random hexamer priming and moloney murine leukaemia virus (MMLV) reverse transcriptase. Quantification of DQA1 mRNA species using a set of six group‐specific primer pairs for the detection of HLA‐DQA1*01, *02, *03, *04, *05 and *06 was carried out on an ABI PRISM GeneAmp 7700 Sequence Detection System (Perkin Elmer, Foster City, CA) with real‐time detection and quantification taking advantage of the fluorescence TaqMan technology (Perkin Elmer, Foster City, CA). Normalization of cDNA templates was achieved by glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) quantification. In addition, the total amount of mRNA produced by HLA‐DQA1 and HLA‐DRA1 expression was quantified for comparison. Subsequently, this approach was validated using Raji and HUT‐78 cell lines and tested with peripheral mononuclear cells (PBMC) of 45 samples taken from healthy volunteers. The sensitivity was determined with ≥ 102 copies. Comparison of the allele‐specific DQA1 expression with the total expression of DQA1 and DRA1 mRNA indicated that DQA1*04 expression was increased compared with the expression of other alleles of the DQA1 gene. Thus, allele‐specific quantification of DQA1 gene products could be achieved by real‐time RT–PCR suitable for the analysis of differential expression of DQA1 mRNAs in homozygote and heterozygote combinations.
Expression of low‐frequency Ala108Pro substitution in the platelet glycoprotein Ibβ gene
Authors: Kunishima S. , Gassner C. , Inoue C. , Kamiya T. , Ozawa K. 
Published: December 2004

SummaryWe determined the gene frequency of the glycoprotein (GP) Ibβ Ala108Pro substitution. The Pro108 allele was not found in 208 healthy Japanese and 200 healthy Caucasians. In vitro expression studies showed surface expression of the GPIbβ Pro108 variant, suggesting the possibility of the involvement of the substitution as an alloantigen.
Jun oncoproteins do not function as primary transcription factors for the mouse major histocompatibility complex class I H‐2 genes in fibroblasts
Authors: Hatina J. , Reischig J. 
Published: December 2004

SummaryThere are several reports in the literature focusing on regulation of major histocompatibility complex (MHC) class I genes by transcription factors of the jun family. The methods employed in these reports differed in various respects, and their results are inconsistent. In mouse Lewis lung carcinoma, B16‐melanoma and F9‐teratocarcinoma cell lines, c‐jun was characterized as a transcriptional activator of the murine MHC class I H2‐Kb gene, while c‐jun was identified as a direct transcriptional repressor of the swine class I PD1 gene, and c‐jun stably transfected clones of mouse L‐fibroblasts markedly reduced their H‐2 class I gene expression. In this study, we attempted to reproduce this last effect by means of transient transfection coupled to Northern hybridization, upon transfecting L‐fibroblasts with expression vectors for all jun family members as well as with an array of c‐jun‐derived dominant negative mutants. No change in H‐2 class I expression could be identified. Next, we derived two additional fibroblastic cell lines from the fibrosarcoma of the H2‐Kk/v‐jun transgenic mouse and transfected them with the two most potent c‐jun dominant negative mutants, again without eliciting any change in H‐2 class I mRNA level. We conclude that the negative regulation of H‐2 class I genes by c‐jun in cells of the fibroblastic lineage is not a primary effect.
Lack of association of the interleukin‐1 receptor antagonist gene with palmoplantar pustulosis in Japanese
Authors: Niizeki H. , Yokoyama M. , Inamoto N. , Nishikawa T. , Naruse T. , Inoko H. , Hashigucci K. 
Published: December 2004

SummaryWe analysed a polymorphism of the interleukin (IL)‐1 receptor antagonist (IL1RN) gene in 93 Japanese patients with palmoplantar pustulosis (PPP). None of the IL1RN alleles was significantly increased in the patients compared with controls. Because PPP has been reported to be associated with the tumour necrosis factor (TNF) region, we examined the association between the TNF and IL1RN genes. There was a difference in IL1RN*2 positivity between patients with and without the AA genotype of the TNF gene. In contrast, such a difference was not found in controls. These data indicate a possible epistatic effect between TNF and IL1RN linked genes for susceptibility to the pathogenesis of PPP.
Free energy and kinetics of dissolution of Sokoto rock phosphate and the implications for replenishing phosphorus in the savanna soil of Nigeria
Authors: Agbenin J. O. 
Published: December 2004

SummaryThe direct application of Sokoto phosphate rock to restore phosphorus in the savanna soil of Nigeria has not been very successful. The dissolution of Sokoto phosphate rock was investigated in three electrolyte solutions – 0.01 m CaCl2, NaCl and KCl – at pH range 3.5–7.0 under laboratory conditions to provide solubility and kinetic data that are required to develop guidelines for direct application in the field. The phosphate rock dissolved in the salt solutions in the order KCl > NaCl > CaCl2. Particle size and ionic strength had no significant effect on the dissolution. The standard free energy of reaction ΔG°R in an acidic solution with no basic cations was −38 kJ mol−1. If Ca2+ ions were in the acidic solution, then ΔG°R increased to 210 kJ mol−1, 170 kJ mol−1 for Na+ ions, and 107 kJ mol−1 for K+ ions in the solution. The theoretical solubility constant (Ks) calculated from the relation ΔG° = −RT ln Ks gave Ks = 106.7 in an acidic solution without basic cations, but decreased to 10−36.8 with Ca2+ ions in solution, 10−29.8 with Na+ ions, and 10−18.8 with K+ ions in solution. At pH ≥ 5.5, the dissolution was more constrained by Ca2+ ions or basic cations in solution than by availability of protons. The kinetics of the dissolution reaction was best described by a power function: Ct = atb, where Ct is the amount of P released from the rock phosphate at time t, and a and b are fitting parameters. An Elovich and a parabolic diffusion expression equally gave satisfactory fits to the dissolution data, suggesting that the rate of dissolution was limited by a combination of film‐ and intra‐particle diffusion. To utilize this rock phosphate as an effective source of P, management practices that increase Ca sinks and the supply of protons to the soil are necessary. In the savanna, increasing the soil's organic matter greatly enhances cation exchange capacity and availability of protons. The practice should provide adequate sinks for Ca2+ and the acidic environment required for the release of P from rock phosphate.
A model describing the interactions between anaerobic microbiology and geochemistry in a soil amended with glucose and nitrate
Authors: Dassonville F. , Renault P. , Vallès V. 
Published: December 2004

SummaryUnder anaerobic conditions, microbes closely interact with geochemical reactions and can have an impact on the soil, the deep vadose zone, the underlying aquifer and the atmosphere. We have designed a model combining anaerobic microbial activities with geochemical reactions in the soil, and assessed it in batch experiments. The model describes the dynamics of six functional microbial communities, their decomposition after death, and the catabolism of carbohydrates through denitrification, dissimilatory NH4+ production, Fe(III) reduction, fermentation, acetogenesis, and SO42– reduction. It was combined with a model that thermodynamically describes acid–base, reduction–oxidation and complexation reactions in solution, and kinetic precipitation and dissolution. Batch incubations were done on a Calcic Cambisol, either without amendment, or after supplying (i) glucose or (ii) glucose and NO3–. Gases, mineral cations and anions, glucose, fatty acids and alcohols were measured during incubation. Net production of CO2 was similar for both glucose treatments, about 40 times larger than in the control. For the glucose treatments, the main microbial activities were fermentation, acetogenic transformation of ethanol, and oxidation of H2. When the soil was enriched with NO3–, no H2 was produced, and microbial activities were rapidly inhibited by NO2–. The model shows these trends as well as geochemical characteristics including pH and reduction–oxidation potential.
Competition between the nymphs of two regionally co‐occurring species of Notonecta (Hemiptera: Notonectidae)
Authors: Briers Robert A. , Warren Philip H. 
Published: December 2004

1. Two species of freshwater invertebrate predator, Notonecta maculata and N. obliqua, showed a negative association in a series of small, man‐made ponds in the Peak National Park, Derbyshire, U.K. The present study examines the potential role of interspecific interactions among nymphs on this regional distribution pattern.2. The survival, development and feeding efficiency of nymphs were examined in laboratory and field mesocosm experiments with intra‐ and interspecific competition and contrasting environmental complexity.3. Survival to adulthood and mean lifespan varied significantly in interspecific competition treatments in both laboratory and field experiments, with N. maculata showing higher survival in the simple environment and N. obliqua higher survival in the complex environment.4. Variations in feeding efficiency were consistent with the survival trends: N. maculata had a higher efficiency in the simple environment, whereas N. obliqua had greater efficiency in the complex environment. There was evidence of a developmental response in feeding efficiency, with differences between species increasing with age.5. These results suggest that the relative competitive abilities of the two species are affected by habitat complexity, and that competition between species may modify the species distribution where they co‐occur.
Population dynamics of planktonic rotifers in Lake Loosdrecht, the Netherlands, in relation to their potential food and predators
Authors: Ooms‐Wilms A. L. , Postema G. , Gulati R. D. 
Published: December 2004

1. This study uses descriptive data to examine the shift in dominance in the rotifer community in summer from Keratella cochlearis to Anuraeopsis fissa in a shallow eutrophic lake. Population density and egg ratio were estimated from May to September for these small loricate rotifers, as well as the soft‐bodied Filinia longiseta and Polyarthra spp., to compare rates of population increase, birth and death.2. Keratella cochlearis was succeeded by A. fissa in late May, perhaps as a result of the shorter egg development times of the latter at temperatures > 15 °C, and species‐specific responses to food and predation. Population variables suggest that the decline of K. cochlearis was the result of a food shortage which caused a decrease in reproduction and increased mortality.3. High population densities of A. fissa and Polyarthra spp. were associated with low egg ratios, birth rates and rates of increase within a species, suggesting intraspecific competition. The egg ratios of the two soft‐bodied rotifers were strongly intercorrelated in the study period, although their diets supposedly differ. The egg ratios of A. fissa showed positively correlated fluctuations with the abundance of diatoms.4. Short periods of higher rates of increase of A. fissa conferred advantage to this rotifer and manifested in its dominance. The mean birth rates of A. fissa and F. longiseta were twice as high as for K. cochlearis. Furthermore, death rates of loricate and soft‐bodied rotifers were similar and high, which suggests that food shortage similarly increased death rates, or that predation may be sometimes substantial for soft‐bodied and loricate species, or both.5. Predation was probably not an important factor in steering the seasonal succession in the lake. A difference in abilities of the studied rotifers to exploit resources seems more important. Perhaps temperature is also a factor, but the specifics remain unclear and await more experimental work.
Effects of precipitation and soil water potential on drought deciduous phenology in the Kalahari
Authors: Jolly William M. , Running Steven W. 
Published: December 2004

AbstractWe utilized an ecosystem process model to investigate the influence of precipitation and soil water potential on vegetation phenology in the semi‐arid, drought‐deciduous ecosystems in the Kalahari region of South Africa. The timing of leaf flush was assumed to be the first day during which a rainfall event exceeded that day's estimate of potential evapotranspiration after a defined dry season. Leaf senescence was assumed to be a dynamic feedback between soil water potential and net plant carbon gain and was determined by dynamically modeling the effects of concomitant trends in soil water potential and net primary production on leaf area index (LAI). Model predictions of LAI were compared with satellite‐derived normalized difference vegetation indices (NDVI) for 3 years at two sites along the Kalahari transect. The mean absolute error for the prediction of modeled leaf flush date compared with leaf flush dates estimated from NDVI were 10.0 days for the Maun site and 39.3 days for the Tshane site. Correlations between model predicted 10‐day average LAI and 10‐day composite NDVI for both Maun and Tshane were high (ρ=0.67 and 0.74, respectively, P<0.001), suggesting that this method adequately predicts intra‐annual leaf area dynamics in these dry tropical ecosystems.
Raphidascaris acus (Bloch, 1779) larvae infections of the stone loach, Barbatula barbatula (L.), from the River Haná, Czech Republic
Authors: Koubková B , Baruš V , Prokeš M , Dyková I 
Published: December 2004

AbstractThe stone loach, Barbatula barbatula (L.), is a typical and dominant intermediate host of Raphidascaris acus in lowland streams of Central Europe. The prevalence of infection of R. acus in B. barbatula from the River Haná ranged throughout the year from 73.3 to 100%. The abundance and the mean intensity of infection also varied throughout the year with a peak in September. Larvae were located mainly in the liver parenchyma. High numbers of larvae and their migration through the tissue caused cyst‐ or abscess‐like formations in the host parenchyma. The severity of the disease condition ranged from mild to severe. We speculate that the infection of stone loach by R. acus larvae regulates the population density and abundance of the intermediate host in lowland streams where natural predators are absent.