bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intranasal inoculation of Chlamydia trachomatis mouse pneumonitis agent induces significant neutrophil infiltration which is not efficient in controlling the infection in mice
Authors: Bai Hong , Yang Jie , Qiu Hongyu , Wang Shuhe , Fan Yijun , Han Xiaobing , Xie Shusheng , Yang Xi 
Published: January 2005

SummaryPrevious studies have shown that chlamydial infection is accompanied by significant infiltration of neutrophils at the site of infection. However, the role of neutrophils in host defence against chlamydial infection is not clearly understood. Using genetically different inbred mouse strains and CXCR‐2 gene knockout (KO) mice, we examined the mechanism for neutrophil recruitment and the role of neutrophils during chlamydial lung infection. Our data showed that C3H mice exhibited significantly higher and more persistent neutrophil infiltration in the lung than did C57BL/6 mice following Chlamydia trachomatis mouse pneumonitis infection. The massive neutrophil infiltration in C3H mice was paralleled by high‐level expression of CXCR‐2 and its ligands, CXC chemokines (macrophage inflammatory protein 2, cytokine‐induced neutrophil attractant (KC) and lipopolysaccharide‐induced CXC chemokine), and proinflammatory cytokines (tumour necrosis factor‐α, interleukin‐1 and interleukin‐6) in the lung. Although much greater infiltration of neutrophils was observed in C3H mice than in C57BL/6 mice, the former mice had more severe disease and higher in vivo chlamydial growth than the latter. Moreover, CXCR‐2 KO mice, which revealed a dramatic reduction in neutrophil activity, showed comparable chlamydial infection to wild‐type mice. These results suggest that neutrophils are not efficient for controlling chlamydial lung infection.
Antibody repertoire development in fetal and neonatal piglets. XI. The thymic B‐cell repertoire develops independently from that in blood and mesenteric lymph nodes
Authors: McAleer Jeremy , Weber Patrick , Sun Jishan , Butler John E. 
Published: January 2005

SummaryThe origin and function of thymic B cells is currently unresolved. In the present study we compared VH gene repertoire diversification in >3500 cloned VDJs (from 11 animals at three time‐points, using three to five animals per time‐point) that were expressed with immunoglobulin (Ig)M, IgD, IgG, IgA and IgE in thymus, mesenteric lymph nodes (MLN) and peripheral blood B cells (PBB) of newborn piglets and 5‐week‐old isolator piglets maintained germfree (GF) or colonized with Escherichia coli. The results showed that the repertoire expressed with IgM, IgD, IgG and IgA in PBB and MLN remained polyclonal, undiversified and unselected in piglets maintained GF for 5 weeks, that age and colonization resulted in significant repertoire diversification of IgG and IgA in the MLN and of IgG in blood, that the thymic B‐cell repertoire was polyclonal, unaffected by colonization and showed no clonal selection in any isotype, and that the thymic IgA and IgE repertoires were more diverse at birth than the repertoire of any isotype in MLN or PBB. IgD was seldom recovered from the PBB of newborn piglets or at any time‐point in thymus, but was recovered in the MLN of all 11 animals examined. The IgD and IgM repertoires in all tissues remained polyclonal and unselected, although VH usage by IgD transcripts did not always parallel that of IgM in the same tissue. Therefore, isotype‐switched B cells in the thymic medulla cannot be accounted for by immigration of B cells diversified by colonization of the gut, and thymic B cells undergo switch recombination and repertoire diversification before birth without clonal selection.
Aberrant regulation of interleukin‐12 receptor β2 chain on type 1 cytokine‐stimulated T lymphocytes in type 1 diabetes
Authors: Skarsvik Susanne , Ludvigsson Johnny , Vaarala Outi 
Published: January 2005

SummaryAn aberrant mitogen‐induced polarization of peripheral blood T cells has been associated with type 1 diabetes (T1D). We studied, in T1D, type 1 and 2 cytokine‐induced expression of the interleukin‐12 receptor β2 chain (IL‐12Rβ2 chain), which plays a critical role in regulating T‐cell polarization. Peripheral blood lymphocytes from children with newly diagnosed T1D (n = 10; mean age 10 years), from children with longstanding T1D (n = 8; mean age 12·9 years) and from healthy children (n = 15; mean age 11·5 years) were stimulated with phytohaemagglutinin (PHA) in a type 1 (IL‐12 and anti‐IL‐4) or a type 2 (IL‐4 and anti‐IL‐12) cytokine environment. Secretion of interferon‐γ (IFN‐γ), IL‐5 and IL‐13, as detected by enzyme‐linked immunosorbent assay (ELISA), and expression of the IL‐12Rβ2 chain on CD4 and CD8 cells by flow cytometry, were analysed. Children with newly diagnosed and longstanding T1D had lower expression levels of the IL‐12Rβ2 chain on IL‐12Rβ2 chain‐positive CD4 T cells (for a type 1 or a type 2 cytokine environment: P = 0·01 and P = 0·002 or P = 0·02 and P = 0·01, respectively) and on IL‐12Rβ2 chain‐positive CD8 T cells (for a type 1 or a type 2 cytokine environment: P = 0·007 and P = 0·0007 or P = 0·003 and P = 0·01, respectively) when compared to healthy children. A decreased percentage of IL‐12Rβ2 chain‐expressing CD4 T cells (P = 0·07 and P = 0·03) and CD8 T cells (P = 0·004 and P = 0·01) and increased secretion of IL‐13 (P = 0·006 and P = 0·04) in a type 1 cytokine environment was seen in both groups of patients. Peripheral blood T cells from patients with both newly diagnosed and longstanding T1D showed poor polarization towards type 1 cells.
Overlap of gastrointestional symptom complexes in a US community
Authors: Locke G. R. , Zinsmeister A. R. , Fett S. L. , Melton L. J. , Talley N. J. 
Published: January 2005

Abstract  Background:  Although the Rome criteria define a number of individual functional gastrointestinal disorders, people may have symptoms of multiple disorders at the same time. In addition, therapies may be effective in subsets of people with specific disorders, yet at the same time help people with multiple disorders.Aim:  To estimate the prevalence of combinations of gastrointestional (GI) symptom complexes.Methods:  A valid self report questionnaire which records GI symptoms was mailed to an age‐ and gender‐stratified random sample of Olmsted County, MN residents aged 30–64 years. Standard definitions were used to identify people with gastro‐oesophageal reflux, dyspepsia, irritable bowel syndrome (IBS), constipation and diarrhoea. The prevalence of people meeting multiple symptom complexes was estimated. Specifically, combinations of dyspepsia, IBS and constipation were compared to dyspepsia, IBS and diarrhoea.Results:  A total of 657 (69%) of 943 eligible subjects responded; 643 provided data for each of the necessary symptom questions. Each two‐way combination of symptom group was present in between 4 and 9% of the population; each three‐way combination was present in 1–4% of the population. The overlap between dyspepsia, IBS and constipation was similar to dyspepsia, IBS and diarrhoea, except body mass index was higher in the diarrhoea overlap group (P = 0.03).Conclusion:  Symptom complex overlap is common in the community; for each condition, the majority of sufferers reported an additional symptom complex. This overlap of symptoms challenges the current paradigm that functional GI disorders represent multiple discreet entities.
Is gastric electrical stimulation superior to standard pharmacologic therapy in improving GI symptoms, healthcare resources, and long‐term health care benefits?
Authors: Cutts T. F. , Luo J. , Starkebaum W. , Rashed H. , Abell T. L. 
Published: January 2005

Abstract  Context:  Severe upper gastrointestinal (GI) motor disorders, including gastroparesis (GP), can consume significant health care resources. Many patients are refractory to traditional drug therapy.Objective:  To compare symptoms, healthcare resource utilization and costs in two groups of patients with the symptoms of GP: those treated via gastric electrical stimulation (GES) and those treated with traditional pharmacological agents in an intensive outpatient program (MED).Design:  A long‐term comparison of patients with devices (n = 9) vs intensive medical therapy (n = 9).Setting and patients: A total of 18 eligible patients with the symptoms of GP reported for 1‐year baseline and long‐term treatment for 3 years.Interventions:  Patients with the symptoms of GP were treated by a GES or intensive medical therapy (MED).Main outcome measures:  GP Symptoms, healthcare resource utilization using investigator‐derived independent outcome measure score (IDIOMS) and total hospital (inpatient and outpatient) billing costs.Results:  Gastrointestinal symptoms were significantly different from baseline (F = 3.03, P < 0.017) with GP patients treated via GES showing more sustained improvement over 36 months than those treated via MED. Healthcare resource usage, measured via the IDIOMS, significantly improved at 12, 24 and 36 month follow‐up for GES patients (F = 10.49, P < 0.001), compared with patients receiving medical therapy, who demonstrated further deterioration. GP patients treated via GES also proved superior to medical therapy at 24 and 36 months with regard to decreased costs (F = 4.85, P < 0.001). Within group comparisons indicated significantly reduced hospital days for both patient groups; however, no statistical differences were noted between groups in terms of hospital days. Three of nine patients in the MED group died primarily from i.v. access related problems; none of the GES patients died.Conclusion:  We conclude that GES is more effective in improving long‐term GI symptoms and costs, and decreasing use of healthcare resources than intensive medical therapy, in this sample of patients with the symptoms of GP followed for 3 years. Certain patients with GP form a high‐risk group in terms of costs, quality of life, morbidity and mortality.
Reproducibility of meal‐induced transient lower oesophageal sphincter relaxations in patients with gastro‐oesophageal reflux disease
Authors: Boeckxstaens G. E. , Hirsch D. P. , Verkleij C. B. , Lei A. , Holman R. , Lehmann A. , Rydholm H. 
Published: January 2005

Abstract Aim:  To calculate the number of subjects required in trials investigating drugs reducing the number of transient lower oesophageal sphincter relaxations (TLOSRs), the inter‐ and intra‐individual variability of TLOSRs were determined, using meal ingestion as a trigger of TLOSRs and reflux.Methods:  A total of 23 gastro‐oesophageal reflux disease (GORD) patients with no to grade B oesophagitis and a hiatal hernia ≤3 cm underwent oesophageal manometry and pHmetry 1 h before and 3 h after ingestion of a solid meal on two separate days approximately 4 weeks apart. Reflux episodes and the underlying mechanisms and the number of TLOSRs were evaluated.Results:  The number of TLOSRs, reflux episodes and % time with pH < 4 after meal ingestion did not differ significantly between the two sessions. The intra‐individual variation of TLOSRs in the 3 h postprandial period (24.4) was smaller compared with the inter‐individual variation (47.5). Transient lower oesophageal sphincter relaxations were the predominant cause of reflux accounting for 61 ± 7 and 70 ± 5% of the reflux episodes in visits 1 and 2, respectively.Conclusions:  These data for the first time provide information on the variability of TLOSRs and reflux evoked by meal ingestion, which is of crucial importance for the design and power calculations of future clinical studies evaluating the efficacy of new drugs targeting TLOSRs.
Accumulation and localization of aluminium in root tips of loblolly pine seedlings and the associated ectomycorrhiza Pisolithus tinctorius
Authors: MOYER‐HENRY K. , SILVA I. , MACFALL J. , JOHANNES E. , ALLEN N. , GOLDFARB B. , RUFTY T. 
Published: January 2005

ABSTRACTEvidence from past studies suggests that loblolly pine may be tolerant of Al. The experiments described in this manuscript were initiated to examine Al tolerance and Al accumulation in the pine root and the degree of Al accumulation in fungal hyphae when pine roots were colonized with the ectomycorrhiza Pisolithus tinctorius. The experiments used lumogallion staining and confocal microscopy to localize Al in root and fungal structures. The results clearly showed that loblolly pine seedlings were highly resistant to Al. A decrease in primary root extension could not be detected until Al+3 activities approached 40 µmol L−1, and extension was suppressed only 30% at an Al+3 activity of 580 µmol L−1. This contrasted with the response of the Al‐sensitive ‘check’ species soybean, where primary root extension was severely restricted at Al+3 activities lower than 5 µmol L−1. Tissue Al measurements and lumogallion fluorescence of longitudinal sections of the pine root tip indicated that tolerance was associated with both Al exclusion from the tip region and compartmentalization of absorbed Al in peripheral cell areas outside of the meristem. In lateral roots colonized with ectomycorrhizae, lumogallion fluorescence showed that large amounts of Al accumulated at the fungal mantle and in areas with the Hartig net. At higher magnification, lumogallion indicated substantial Al accumulation inside hyphae. Little Al could be detected in lateral root cells. The results show that pine possesses multiple mechanisms that can contribute to Al tolerance in acid field soils.
Blockage of apoplastic bypass‐flow of water in rice roots by insoluble salt precipitates analogous to a Pfeffer cell
Authors: RANATHUNGE K. , STEUDLE E. , LAFITTE R. 
Published: January 2005

ABSTRACTPrecipitates of insoluble inorganic salts were used to clog apoplastic pores in cell walls of the outer part of rice roots (OPR) in two rice cultivars (lowland cv. IR64 and upland cv. Azucena). Aerenchyma of two different root zones (20–50 and 50–100 mm from the apex) was perfused with 1 m m potassium ferrocyanide (K4[Fe(CN)6]) while the whole root segments were bathed in 0.5 m m copper sulphate (CuSO4) medium. In another experiment, salts were applied on opposite sides of the OPR. The copper‐ferrocyanide precipitation technique resembles the famous osmotic experiments of the German botanist Wilhelm Pfeffer, in which he used them with clay diaphragms. Precipitates were observed on the side where ferrocyanide was applied, suggesting that Cu2+ and SO42– were passing the barrier including the Casparian bands of the exodermis much faster than ferrocyanide. There was a patchiness in the formation of precipitates, correlated with the maturation of the exodermis. The intensity of copper ferrocyanide staining decreased along developing rice roots. No precipitates were observed in mature parts beyond 70–80 mm from the root apex, except for sites around the emergence of secondary roots, which were fairly leaky to both water and ions. Blockage of the apoplastic pores with precipitates caused a three‐ to four‐fold reduction of hydraulic conductivity of the OPR (LpOPR). The reflection coefficient of the OPR (σsOPR) increased in response to the blockage with precipitates. The osmotic versus diffusive water permeability ratios of the OPR (PfOPR/PdOPR) were around 600 for immature and 1200 for mature root segments. Treatment significantly affected the bulk rather than the diffusive water flow and caused a three‐ to five‐fold reduction of the PfOPR/PdOPR ratios. Results indicated that despite the existence of an exodermis with Casparian bands, most of the water moved around cells rather than using the cell‐to‐cell passage.
Transverse hydraulic redistribution by a grapevine
Authors: SMART D. R. , CARLISLE E. , GOEBEL M. , NÚÑEZ B. A. 
Published: January 2005

ABSTRACTRoot hydraulic redistribution has been shown to occur in numerous plant species under both field and laboratory conditions. To date, such water redistribution has been demonstrated in two fundamental ways, either lifting water from deep edaphic sources to dry surface soils or redistributing water downward (reverse flow) when inverted soil Ψs gradients exist. The importance of hydraulic redistribution is not well documented in agricultural ecosystems under field conditions, and would be important because water availability can be temporally and spatially constrained. Herein we report that a North American grapevine hybrid (Vitis riparia × V. berlandieri cv 420 A) growing in an agricultural ecosystem can redistribute water from a restricted zone of available water under a drip irrigation emitter, laterally across the high resistance pathways of the trunk and into roots and soils on the non‐irrigated side. Deuterium‐labelled water was used to demonstrate lateral movement across the vine's trunk and reverse flow into roots. Water redistribution from the zone of available water and into roots distant from the source occurred within a relatively short time frame of 36 h, although overnight deposition into rhizosphere soils around the roots was not detected. Deuterium was eventually detected in rhizosphere soils adjacent to roots on the non‐irrigated side after 7 d. Application of identical amounts of water with the same deuterium enrichment level (2%) to soils without grapevine roots showed that physical transport of water through the vapour phase could not account for either downward or transverse movement of the label. These results confirmed that root presence facilitated the transport of label into soils distant from the wetted zone. When deuterium‐labelled water was allowed to flow directly into the trunk above the root–trunk interface, reverse flow occurred and lateral movement across the trunk and into roots originating around the collar region did not encounter large disproportionate resistances. Rapid redistribution of water into the entire root system may have important implications for woody perennial cultivars growing where water availability is spatially heterogeneous. Under the predominantly dry soil conditions studied in this investigation, water redistributed into roots may extend root longevity and increase the vines water capacitance during periods of high transpiration demand. These benefits would be enhanced by diminished water loss from roots, and could be equally important to other cited benefits of hydraulic redistribution into soils such as enhancement of nutrient acquisition.
Influence of anoxia on whole plant sulphur nutrition of flooding‐tolerant poplar (Populus tremula × P. alba)
Authors: HERSCHBACH C. , MULT S. , KREUZWIESER J. , KOPRIVA S. 
Published: January 2005

ABSTRACTThe investigations reported herein were performed to test whether anoxic soil conditions changed the sink strength of the roots for reduced sulphur and therefore transport of sulphur in the phloem, and whether increasing sulphide contents in anoxic soils due to bacteria activity causes changes in sulphate assimilation of the roots. Anoxic conditions caused by flooding of the flooding‐tolerant tree species Populus tremula × P. alba led not only to changes in carbon metabolism, but also influenced sulphate assimilation. In the roots, activity and transcript of adenosine 5′‐phosphosulphate (APS) reductase, the key enzyme of the sulphate assimilation pathway, completely disappeared, but the Cys content increased 6.7 times after 15 d of flooding. A higher glutathione content of phloem exudates after 3 and 7 d of flooding indicates an increased transport of reduced sulphur to the roots. However, the export rate of 35S‐sulphur out of mature leaves after flap feeding 35S‐sulphate was not different between flooded and control poplars. Since the allocation to the roots was diminished, enhanced phloem contents of GSH indicate a diminished sink strength of the roots rather than an enhanced sink strength. Therefore, a higher transport of GSH in the phloem could not be responsible for the higher Cys content in the roots. As protein contents were unaffected the higher Cys content in roots could also not originate from protein breakdown. Enhanced O‐acetylserine (thiol) lyase (OASTL) activity were measured in the roots demonstrating an uncoupling of sulphate reduction and Cys synthesis. A possible contribution in detoxification of sulphide produced in the anoxic soil is discussed.
Growth responses and fitness costs after induction of pathogen resistance depend on environmental conditions
Authors: DIETRICH R. , PLOSS K. , HEIL M. 
Published: January 2005

ABSTRACTFitness costs of resistance are among the most widely discussed explanations for the evolution of induced resistance, but studies on induced resistance to pathogens are scarce and contradictory. In the present study the influence of nitrogen supply, length of the growing period and competition on the seed production of Arabidopsis in response to treatment with the chemical resistance elicitor BION® was investigated. BION® treatment elicited resistance to the bacterial pathogen Pseudomonas syringae, and biochemical changes after BION® treatment were similar to those observed after bacterial infection. Induced plants grew more slowly during the first week after resistance induction, for which they then compensated by exhibiting faster growth than controls. Whether or not induced plants produced less seeds than controls depended on growing conditions. Costs, no costs and even higher seed production by induced plants were observed in experiments differently combining abiotic conditions. A higher seed production by induced plants arose particularly when the vegetation period was short, most probably a consequence of senescence‐related processes that had been activated by resistance elicitation. Induced plants, however, produced less seeds when competing with controls and experiencing a full growing period. Studies controlling only some of the critical environmental factors can easily lead to apparently contradictory results, which in fact represent different outcomes of a complex interplay of factors.
Natural variation in the regulation of leaf senescence and relation to other traits in Arabidopsis
Authors: LEVEY S. , WINGLER A. 
Published: January 2005

ABSTRACTLeaf senescence results in the recycling of nutrients, thereby providing resources required for growth and reproduction. In this study, the effect of day‐length on leaf senescence in eight different Arabidopsis thaliana ecotypes was determined and the relationship between senescence and other morphological and life history traits was analysed. A significant variation in the start and extent of leaf senescence depending on the genetic background and the response to day‐length was found. Whereas senescence of early flowering ecotypes was accelerated by long days, no effect of day‐length on senescence could be found in late flowering Kas‐1 plants. Senescence in the different ecotypes was associated with other traits, such as floral transition, the total number of fruits, the total number of leaves and the maximum chlorophyll content. Plants that bolted early also senesced early, produced fewer leaves, accumulated less chlorophyll, but produced more fruits. The present results indicate that senescence may be a key component in the trade‐off between investment in photosynthetic capacity and reproduction. The relationship between senescence and other traits was maintained independent of whether differences in senescence were caused by genetic (ecotype) or environmental (day‐length) variation, suggesting that genetic and environmental factors affect these traits through common regulatory pathways.