bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human monocyte‐derived dendritic cells are chemoattracted to C3a after up‐regulation of the C3a receptor with interferons
Authors: Gutzmer Ralf , Lisewski Margarete , Zwirner Jörg , Mommert Susanne , Diesel Carola , Wittmann Miriam , Kapp Alexander , Werfel Thomas 
Published: March 2004

SummaryThe anaphylatoxin C3a is an important inflammatory mediator in the innate and adaptive immune systems. Recent reports in various animal models have fostered the role of C3a in mediating allergic reactions such as pulmonary allergies. However, data in humans are limited and the cellular targets for C3a are not fully understood. We sought to explore human dendritic cells as a new target for C3a, because C3a receptor (C3aR) expression has been described on myeloid cells, and dendritic cells are likely make contact with C3a at sites of inflammatory reactions. In this study, we demonstrated the expression of the C3aR on human monocyte‐derived dendritic cells (MoDC) and its up‐regulation by interferon (IFN)‐α, IFN‐γ and prostaglandin E2 (PGE2). The strongest up‐regulation was yielded by the combination of IFN‐α+ IFN‐γ. Tumour necrosis factor‐α (TNF‐α) down‐regulated the C3aR. After up‐regulation of the C3aR by IFN‐α+ IFN‐γ, C3a significantly up‐regulated the surface expression of CD54, CD83 and CD86, but not of CD40, CD80 or human leucocyte antigen (HLA)‐DR. C3a had no effect on the production of interleukin (IL)‐10 or IL‐12p70, or on the capacity of MoDC to stimulate autologous T‐cell proliferation. However, C3a had a direct migratory effect on MoDC, as indicated by the induction of F‐actin polymerization and migration in Boyden chamber experiments, which was pronounced after up‐regulation of the C3aR with IFN‐α+ IFN‐γ. Therefore, dendritic cells represent another group of target cells that might be recruited by C3a to areas of inflammation, in particular under conditions where IFNs are increased in the surrounding environment.
The chemical composition and some physical properties of a water‐soluble gum from Prosopis africana seeds
Authors: Achi Ome K. , Okolo Ngozika I. 
Published: March 2004

SummaryA water‐soluble gum was extracted from the endocarp capsule of the seed coat of Prosopis africana. The gum yield varied substantially with the method of dehulling. Maximum yield was obtained after boiling in 0.1 m Na2CO3 for 4 h. The effects of two different gum concentrations on the rheological properties of gum solutions were examined. The gum formed viscous solutions at low concentrations and exhibited stable viscosity in the pH range 6.0–8.0. Chemical analyses showed that the purified gum had a composition of 2.4% fat, 1.04% protein, 21.5% crude fibre and a gelation concentration of at least 10%. Galactose and mannose were the major polysaccharides identified. Large reductions in viscosity were observed with the addition of various concentrations of Na+ salts. The activation energies of flow for 2 and 3% gum solutions were in the range of 19.2–22.8 kJ mol−1 and were characteristic of systems with little intra‐ and intermolecular interactions.
Nurse educators’ workplace empowerment, burnout, and job satisfaction: testing Kanter's theory
Authors: Sarmiento Teresa P. , Laschinger Heather K. Spence , Iwasiw Carroll 
Published: March 2004

Background.  Empowerment has become an increasingly important factor in determining college nurse educator burnout, work satisfaction and performance in current restructured college nursing programmes in Canada.Aim.  This paper reports a study to test a theoretical model specifying relationships among structural empowerment, burnout and work satisfaction.Method.  A descriptive correlational survey design was used to test the model in a sample of 89 Canadian full‐time college nurse educators employed in Canadian community colleges. The instruments used were the Conditions of Work Effectiveness Questionnaire, Job Activities Scale, Organizational Relationship Scale, Maslach Burnout Inventory Educator Survey and Global Job Satisfaction Questionnaire.Results.  College nurse educators reported moderate levels of empowerment in their workplaces as well as moderate levels of burnout and job satisfaction. Empowerment was significantly related to all burnout dimensions, most strongly to emotional exhaustion (r = −0·50) and depersonalization (r = −0·41). Emotional exhaustion was strongly negatively related to access to resources (r = −0·481, P = 0·0001) and support (r = −0·439, P = 0·0001). Multiple regression analysis revealed that 60% of the variance in perceptions of job satisfaction was explained by high levels of empowerment and low levels of emotional exhaustion [R2 = 0·596, F (1, 86) = 25·01, P = 0·0001]. While both were significant predictors of perceived job satisfaction, empowerment was the stronger of the two (β = 0·49).Conclusions.  The results provide support for Kanter's organizational empowerment theory in the Canadian college nurse educator population. Higher levels of empowerment were associated with lower levels of burnout and greater work satisfaction. These findings have important implications for nurse education administrators.
A concept analysis of palliative care in the United States
Authors: Meghani Salimah H. 
Published: March 2004

Purpose.  The purpose of this analysis is to trace the evolution of the concept of palliative in the United States, explicate its meanings, and draw comparisons with other related concepts such as hospice care and terminal care.Methods.  Rodgers’ evolutionary method was used as an organizing framework for the concept analysis. Data were collected from a review of CINAHL, MEDLINE, CANCERLIT, PsycINFO and Sociological Abstracts databases using ‘palliative care’ and ‘United States’ as keywords. Articles written in the English language, with an abstract, published between 1965 and 2003 were considered. Data were synthesized to identify attributes, antecedents and consequences of palliative care.Findings.  There has been a significant evolution in understanding of the palliative care concept in the United States over the last few decades, which has resulted in the emergence of new models of palliative care. Four attributes of the current palliative care concept were identified: (1) total, active and individualized patient care, (2) support for the family, (3) interdisciplinary teamwork and (4) effective communication. Results reinforce that cure and palliation are not mutually exclusive categories.Conclusions.  The scope of palliative care has evolved to include a wide range of patient populations who may not be appropriately termed ‘dying’ but for whom alleviation of suffering and improvement of quality of life may be very relevant goals. The ultimate success of the new models of palliative care will eventually rest upon the commitment of health professionals to recognize and integrate the changing concept of palliative care into everyday practice.
Rehabilitation after coronary heart disease: spouses’ views of support
Authors: Kärner Anita M. , Dahlgren Madeleine Abrandt , Bergdahl Björn 
Published: March 2004

Background.  Family presence decreases mortality and improves psychosocial recovery after a coronary heart disease event. In this situation, spousal support seems important for the recovering partner's self‐esteem and mastery. There is inadequate knowledge of how spouses view their supportive roles.Aim.  The aim of this paper is to report a study investigating spouses’ experiences of the rehabilitation phase of their partners’ coronary heart disease and to gain their views about supporting them in lifestyle changes.Method.  Eight male (mean age 61) and 17 female spouses (mean age 53), were interviewed 1 year after their partner's cardiac event. Of the partners, 18 had experienced myocardial infarction and 19 were revascularized. Interview transcripts were analysed qualitatively using a phenomenographic framework.Findings.  The analysis yielded five different views of the spouse's role. The participative role involved taking a practical part in lifestyle changes, communicating empathetically, and being positive about changes. The regulative role was characterized by being either positive or negative about changes, giving practical or cognitive support in order to control the partner's behaviour, and communicating authoritatively. In the observational role the spouse was passive, complied with suggestions, and communicated empathetically. The incapacitated role involved a positive attitude to changes, communicating without making demands, but being unable to provide support because of personal problems. Assuming a dissociative role entailed being negative about changes and authoritatively declaring a reluctance to be involved in the partner's change of lifestyle. Spouses adopted different roles depending on the support situation.Conclusion.  Spouses’ views of their roles in support varied considerably in terms of awareness of the benefits of behavioural changes, style of communication, pattern of co‐operation and support situation. The findings favour the view that a family perspective is important in planning rehabilitation of patients following coronary heart disease.
Altered activity of the P2 isoform of plastidic glucose 6‐phosphate dehydrogenase in tobacco (Nicotiana tabacum cv. Samsun) causes changes in carbohydrate metabolism and response to oxidative stress in leaves
Authors: Debnam Phillip M. , Fernie Alisdair R. , Leisse Andrea , Golding Alison , Bowsher Caroline G. , Grimshaw Caroline , Knight Jacqueline S. , Emes Michael J. 
Published: March 2004

SummaryExpression of one specific isoform of plastidic glucose 6‐phosphate dehydrogenase (G6PDH) was manipulated in transgenic tobacco. Antisense and sense constructs of the endogenous P2 form of G6PDH were used to transform plants under the control of the cauliflower mosaic virus (CaMV) 35S promotor. Recombinant plants with altered expression were taken through to homozygosity by selective screening. Northern analyses revealed substantial changes in the expression of the P2 form of G6PDH, with no apparent impact on the activity of the cytosolic isoenzyme. Analysis of G6PDH activity in chloroplasts showed that despite the large changes in expression of P2‐G6PDH, the range of enzyme activity varied only from approximately 50 to 200% of the wild type, reflecting the presence of a second G6PDH chloroplastic isoform (P1). Although none of the transgenic plants showed any visible phenotype, there were marked differences in metabolism of both sense and antisense lines when compared with wild‐type/control lines. Sucrose, glucose and fructose contents of leaves were higher in antisense lines, whereas in overexpressing lines, the soluble sugar content was reduced below that of control plants. Even more striking was the observation that contents of glucose 6‐phosphate (Glc6P) and 6‐phosphogluconate (6PG) changed, such that the ratio of Glc6P:6PG was some 2.5‐fold greater in the most severe antisense lines, compared with those with the highest levels of overexpression. Because of the distinctive biochemical properties of P2‐G6PDH, we investigated the impact of altered expression on the contents of antioxidants and the response of plants to oxidative stress induced by methyl viologen (MV). Plants with decreased expression of P2‐G6PDH showed increased content of reduced glutathione (GSH) compared to other lines. They also possessed elevated contents of ascorbate and exhibited a much higher ratio of reduced:oxidised ascorbate. When exposed to MV, leaf discs of wild‐type and overexpressing lines demonstrated increased oxidative damage as measured by lipid peroxidation. Remarkably, leaf discs from plants with decreased P2‐G6PDH did not show any change in lipid peroxidation in response to increasing concentrations of up to 15 µm MV. The results are discussed from the perspective of the role of G6PDH in carbohydrate metabolism and oxidative stress. It is suggested that the activity of P2‐G6PDH may be crucial in balancing the redox poise in chloroplasts.
Organellar gene transcription and early seedling development are affected in the rpoT;2 mutant of Arabidopsis
Authors: Baba Kyoko , Schmidt Julien , Espinosa‐Ruiz Ana , Villarejo Arsenio , Shiina Takashi , Gardeström Per , Sane Aniruddha P. , Bhalerao Rishikesh P. 
Published: March 2004

SummaryAn Arabidopsis mutant that exhibited reduced root length was isolated from a population of activation‐tagged T‐DNA insertion lines in a screen for aberrant root growth. This mutant also exhibited reduced hypocotyl length as well as a delay in greening and altered leaf shape. Molecular genetic analysis of the mutant indicated a single T‐DNA insertion in the gene RpoT;2 encoding a homolog of the phage‐type RNA polymerase (RNAP), that is targeted to both mitochondria and plastids. A second T‐DNA‐tagged allele also showed a similar phenotype. The mutation in RpoT;2 affected the light‐induced accumulation of several plastid mRNAs and proteins and resulted in a lower photosynthetic efficiency. In contrast to the alterations in the plastid gene expression, no major effect of the rpoT;2 mutation on the accumulation of examined mitochondrial gene transcripts and proteins was observed. The rpoT;2 mutant exhibited tissue‐specific alterations in the transcript levels of two other organelle‐directed nuclear‐encoded RNAPs, RpoT;1 and RpoT;3. This suggests the existence of cross‐talk between the regulatory pathways of the three RNAPs through organelle to nucleus communication. These data provide an important information on a role of RpoT;2 in plastid gene expression and early plant development.
Temporally and spatially controlled induction of gene expression in Arabidopsis thaliana
Authors: Maizel Alexis , Weigel Detlef 
Published: March 2004

SummaryTemporally and spatially regulated induction of gene expression is an important tool of genetic analysis. In plants, several systems are available for spatially unregulated induction of gene expression, or for spatially regulated expression. Here, we describe a new system that provides both temporal and spatial control for transgene expression. It combines the advantages of its two constituent components: temporally regulated activity of the ethanol‐dependent AlcR transcription factor, and tissue specificity of a plant promoter. As a proof of principle, transgenic lines were developed in which the promoter of the meristem identity gene LEAFY (LFY) provided flower‐specific expression of the AlcR activator. Tissue‐specific activity of AlcR was confirmed with a responder in which the β‐glucuronidase (GUS) reporter was under the control of the alcA response element. As expected, reporter activity in a pattern typical for the LFY promoter was ethanol dependent. Next, we placed the LFY coding sequenced under control of the AlcA response element. In a strong lfy‐12 background, this construct in combination with the LFY:AlcR driver provided complete, ethanol‐dependent rescue of the lfy phenotype, including restoration of fertility. Apart from facilitating the investigation of temporal and spatial requirements of gene activity, this technology will permit new types of genetic modifier screens starting with mutations that otherwise confer lethality or sterility.
Improved tandem affinity purification tag and methods for isolation of protein heterocomplexes from plants
Authors: Rohila Jai S. , Chen Mei , Cerny Ronald , Fromm Michael E. 
Published: March 2004

SummaryA synthetic gene encoding the tandem affinity purification (TAP) tag has been constructed, and the TAP tag assayed for its effects on expression levels and subcellular localization by fusion to green fluorescent protein (GFP) as well as for its effects on steroid‐dependent translocation to the nucleus and transcription when fused to a hybrid glucocorticoid receptor. A nuclear localization signal (NLS) was detected in the calmodulin‐binding protein (CBP) domain and removed by mutation to improve the usefulness of the TAP tag. Additionally, purification improvements were made, including inhibition of a co‐purifying protease, and adding a protein cross‐linking step to increase the recovery of interacting proteins. The improved synthetic TAP tag gene and methods were used to isolate proteins interacting with the hybrid glucocorticoid receptor and to identify them by mass spectrometry. The two proteins identified, HSP70 and HSP90, are known to interact with the glucocorticoid receptor in vivo in mammalian cells and in vitro in plants.
PPR motifs of the nucleus‐encoded factor, PGR3, function in the selective and distinct steps of chloroplast gene expression in Arabidopsis
Authors: Yamazaki Hiroyuki , Tasaka Masao , Shikanai Toshiharu 
Published: March 2004

SummaryPlastid gene expression is regulated by a variety of nuclear genes. We have isolated Arabidopsis thaliana proton gradient regulation 3 (pgr3) mutants, which display aberrant chlorophyll fluorescence because of defects in chloroplast gene expression. High chlorophyll fluorescence (HCF) because of a reduced level of the cytochrome b6/f complex was observed in two alleles, pgr3‐1 and pgr3‐2 but not in pgr3‐3. In contrast, a transient increase in fluorescence after turning off the actinic light, which was ascribed to chloroplast NAD(P)H dehydrogenase (NDH) activity, was impaired in pgr3‐1 and pgr3‐3 but not in pgr3‐2. Both phenotypes were complemented by the introduction of a single gene, PGR3, encoding a protein containing 27 pentatrico‐peptide repeat (PPR) motifs. PPR motifs are present in proteins functioning in the post‐transcriptional regulation of organellar gene expression. The conserved threonine in the motif was substituted by isoleucine in the 15th and 12th PPR motifs in pgr3‐1 and pgr3‐2, respectively, and the conserved leucine by phenylalanine in the final incomplete motif of pgr3‐3. We consider that the different domains of the PPR repeats in PGR3 might have different functions in conferring RNA stability and probably allowing translation as well as recognizing at least two distinct target RNAs.
Biomass, nutrient and pigment content of beech (Fagus sylvatica) saplings infected with Phytophthora citricola, P. cambivora, P. pseudosyringae and P. undulata
Authors: Fleischmann F. , Göttlein A. , Rodenkirchen H. , Lütz C. , Oßwald W. 
Published: March 2004

Summary Fagus sylvatica saplings were infected with Phytophthora citricola, Phytophthora cambivora, Phytophthora pseudosyringae and Phytophthora undulata to study the influence of these root pathogens on total belowground and aboveground biomass, on the nutrient distribution within plants, on the concentration of plastid pigments, including tocopherol and on components of the xanthophyll cycle. Phytophthora citricola and P. cambivora infection significantly reduced total biomass of beech when compared with control plants and finally most of these plants died at the end of the experiment. However, beech invaded by the other two Phytophthora spp. did not differ from control plants and none of them was killed. Fine root length as well as the number of root tips of all infected beeches were reduced between 30 and 50%. The excellent growth of beech infected with P. pseudosyringae and P. undulata when compared with control plants was correlated with a strong increase of important root efficiency parameters. Phytophthora citricola and P. cambivora caused a significant reduction in nitrogen concentration of leaves in comparison with control and other infected plants, whereas this nutrient was slightly increased in fine and coarse roots. Furthermore, the phosphorus and potassium concentrations in leaves were impaired after infection with P. citricola. However, foliar concentrations of Ca and Mg were not affected by the different Phytophthora spp., whereas fine and coarse roots were significantly enriched with Ca in beech infected with P. citricola or P. cambivora. The concentrations of α‐tocopherol and xanthophyll cycle pigments were increased in plants infected by P. citricola and P. cambivora, indicating that several reactive oxygen species might be formed in leaves during infection.
Necrophylactic periderm formation in the roots of western larch and Douglas‐fir trees infected with Armillaria ostoyae. II. The response to the pathogen
Authors: Robinson R. M. , Morrison D. J. , Jensen G. D. 
Published: March 2004

SummaryPeriderm formation was studied in bark samples collected from the roots of western larch (Larix occidentalis) and Douglas‐fir (Pseudotsuga menziesii) trees infected with Armillaria ostoyae. Necrophylactic periderms were formed in advance of infection and successfully restricted continued fungal spread in 68 and 45% of the samples collected from 10‐ and 27‐year‐old western larch, respectively. However, all periderms formed in 11‐ and 25‐year‐old Douglas‐fir had been breached by the advancing fungus. In both species, necrophylactic periderms were commonly breached at the junction of the periderm with the vascular cambium. In western larch, stone phellem often comprised the external phellem layer of necrophylactic periderms with multiple bands of phellem. In 27‐year‐old western larch, infection was often confined to discrete lesions bounded by multiple periderms with multiple bands of phellem. In both tree species, phellem production was greater in response to infection than in response to abiotic wounding.
Analysis of limited fertility in intracytoplasmic sperm injection of sperm obtained by electroejaculation
Authors: Nakamura Yoshihiro , Matsumiya Kiyomi , Kitamura Masaya , Nishimura Kenji , Tsujimura Akira , Takeyama Masami , Kondoh Nobuyuki , Miyazaki Kazunori , Okuyama Akihiko 
Published: March 2004

Background and Aims:  We correlated findings in semen from patients with ejaculatory dysfunction with results of in vitro fertilization using their electroejaculated sperm.Methods and Results:  Electroejaculation was carried out in six patients with the above‐mentioned criteria for a total of eight times. Sperm was obtained in six attempts. Intracytoplasmic injection of these sperm was performed in 156 eggs. Sixty‐seven eggs were fertilized; most of these were injected with motile sperm. Two women became pregnant, both after injection with motile sperm. As previously reported, electroejaculated sperm showed low motility and a low fertilization rate, but even motile sperm had a low fertilization rate.Conclusion:  The results of the present study suggest the importance in fertilization of undetermined factors in addition to sperm motility. (Reprod Med Biol 2004; 3: 9–12)