bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of hepatocyte growth factor and c‐met protein is significantly associated with the progression of oral squamous cell carcinoma in Taiwan
Authors: Chen Yu‐Shan , Wang Jeng‐Tzung , Chang Yu‐Fong , Liu Bu‐Yuan , Wang Yi‐Ping , Sun Andy , Chiang Chun‐Pin
Published: March 2004

Background:  Hepatocyte growth factor (HGF) is a pleotropic growth factor that regulates cell proliferation, migration, survival, tumor angiogenesis, and tumor cell invasion and metastasis. Its diverse biological effects are mediated through its interaction with its receptor, c‐met protein.

Methods:  In this study, we examined the expression of HGF and c‐met protein in 93 specimens of oral squamous cell carcinoma (OSCC), 10 specimens of oral epithelial dysplasia (OED), 14 specimens of oral epithelial hyperkeratosis (OEH), and 16 specimens of normal oral mucosa (NOM) by immunohistochemistry. The HGF and c‐met labeling indices (LIs) in OSCC, OED, OEH, and NOM groups were calculated and compared between groups. The correlation between the expression of HGF or c‐met in OSCCs and clinicopathological parameters, or survival of OSCC patients was analyzed statistically to investigate the possible influence of HGF or c‐met on the progression and prognosis of OSCCs in Taiwan.

Results:  Positive HGF or c‐met staining was mainly cytoplasmic. The mean HGF LI increased significantly from NOM (3.1 ± 5.1%) through OEH (32.5 ± 19.8%) and OED (52.0 ± 19.3%) to OSCC (71.9 ± 28.6%; P = 0.000). The mean c‐met LI also increased significantly from NOM (25.8 ± 30.8%) and OEH (34.4 ± 19.3%) through OED (53.0 ± 20.0%) to OSCC (73.0 ± 29.4%; P = 0.000). Statistical analysis showed that the c‐met LI in either the tumor center or invasion front was significantly associated with T status, N status, and clinical staging of OSCC. However, only the HGF LI in the tumor invasion front was significantly correlated with N status and clinical staging of OSCC.

Conclusion:  Our results suggest that the expression of HGF and c‐met protein is an early event in oral carcinogenesis in Taiwan. The HGF LI in the tumor invasion front and the c‐met LI in either the tumor center or invasion front can predict the progression of OSCCs in Taiwan.
The relationship of proliferating cell density at the invasive tumour front with prognostic and risk factors in human oral squamous cell carcinoma
Authors: Tumuluri Vijay , Thomas Graham A. , Fraser Ian S.
Published: March 2004

BACKGROUND:  We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC).

METHODS:  Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki‐67 antigen using a horseradish peroxidase based two‐step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki‐67 labelling index (LI) was determined by measuring the number of nuclei/mm2 of epithelium.

RESULTS:  Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki‐67 LI compared with early stage of disease (2111 ± 905 vs. 1908 ± 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki‐67 LI than tumours where distant metastasis was not detected (3257 ± 650 vs. 1966 ± 881; P < 0.0001).

CONCLUSIONS:  Cell proliferation, as measured by the Ki‐67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival.
HLA typing in Taiwanese patients with oral submucous fibrosis
Authors: Chen Hsin‐Ming , Hsieh Rhong‐Phong , Yang Hsiang , Kuo Ying‐Shiung , Kuo Mark Yen‐Ping , Chiang Chun‐Pin
Published: March 2004

Background:  A significant association of certain human leukocyte antigens (HLA) and haplotypic pairs with oral submucous fibrosis (OSF) has been reported. However, controversial result of no HLA association with OSF has also been reported. In this study, the phenotype and haplotype frequencies of HLA‐A, ‐B, ‐C, ‐DRB1, and ‐DQB1 in 135 Taiwanese OSF patients were calculated and compared with those in 540 healthy control Taiwanese.

Methods:  The analysis of HLA‐A, ‐B, and ‐C antigens, and of HLA‐DRB1 and ‐DQB1 alleles in OSF patients and healthy control subjects, was performed by serologic typing and DNA typing using polymerase chain reaction with sequence‐specific primers (PCR‐SSP), respectively.

Results:  We found that the phenotype frequency of HLA‐B76 (3.0%) in OSF patients was significantly greater than that (0%) in healthy control subjects (corrected P (Pc) = 0.000). In addition, the haplotype frequencies of HLA‐B48/Cw7 (3.0%), ‐B51/Cw7 (6.7%), and ‐B62/Cw7 (8.2%) in OSF patients were significantly greater than the corresponding haplotype frequencies (0, 0.7, and 1.9%, respectively) in healthy control subjects (Pc = 0.000). The relative risk (RR) values of haplotypes B51/Cw7 (9.57) and B62/Cw7 (4.7) were greater than the RR values of phenotypes B51 (1.81), B62 (2.31), and Cw7 (1.91) in OSF patients. In addition, the etiologic fraction (EF) value of haplotype B51/Cw7 (0.63) was higher than the EF values of phenotypes B51 (0.2) and Cw7 (0.59).

Conclusions:  We conclude that some Taiwanese areca quid (AQ) chewers with particular HLA phenotypes and haplotypes are prone to have OSF. In addition, some particular HLA haplotypes may play more important roles than the individual HLA phenotypes for the genetic susceptibility to OSF. However, the significantly increased HLA phenotype B76 and three of the common HLA haplotypes detected are present in only about 20% of incident cases of OSF.
Primary productivity and species richness: relationships among functional guilds, residency groups and vagility classes at multiple spatial scales
Authors: Bailey S.‐A. , Horner‐Devine M. C. , Luck G. , Moore L. A. , Carney K. M. , Anderson S. , Betrus C. , Fleishman E.
Published: March 2004

One of the major determinants of species richness is the amount of energy available, often measured as primary productivity. Heterogeneity of environmental variables has also been found to influence species richness. Predicting species distributions across landscapes and identifying areas that have high species richness, or vulnerable groups of species, is useful for land management. Remotely sensed data may help identify such areas, with the Normalized Difference Vegetation Index (NDVI) providing an estimate of primary productivity. We examined the relationship between maximum productivity (NDVI), heterogeneity of productivity, and species richness of birds and butterflies at multiple spatial scales. We also explored relationships between productivity, functional guilds and residency groups of birds, and vagility classes of butterflies. Positive linear relationships between maximum NDVI and number of functional guilds of birds were found at two spatial scales. We also found positive linear relationships between maximum NDVI and species richness of neotropical migrant birds at two scales. Heterogeneity of NDVI, by contrast, was negatively associated with number of functional guilds of birds and species richness of resident birds. Maximum NDVI was associated with species richness of all butterflies and of the most vagile butterflies. No association was found between heterogeneity of NDVI and species richness of butterflies. In the Great Basin, where high greenness and availability of water correspond to areas of high species richness and maximum NDVI, our results suggest that NDVI can provide a reliable basis for stratifying surveys of biodiversity, by highlighting areas of potentially high biodiversity across large areas. Measures of heterogeneity of NDVI appear to be less useful in explaining species richness.
Vertebrate herbivores and ecosystem control: cascading effects of faeces on tundra ecosystems
Authors: Van Der Wal René , Bardgett Richard D. , Harrison Kathryn A. , Stien Audun
Published: March 2004

We tested the hypothesis that large herbivores manipulate their own food supply by modifying soil nutrient availability. This was investigated experimentally the impact of faeces on grasses, mosses and soil biological properties in tundra ecosystems. For this, we increased the density of reindeer Rangifer tarandus platyrhynchus faeces and studied the response of a tundra system on Spitsbergen to this single faecal addition treatment for four subsequent years. From the third year onwards faecal addition had unambiguously enhanced the standing crop of grasses, as evidenced by an increase in both shoot density and mass per shoot. Although reindeer grazing across experimental plots was positively related to the abundance of grasses in anyone year, the increase in grass abundance in fouled plots failed to result in greater grazing pressure in those plots. Faecal addition enhanced soil microbial biomass C and N, particularly under wet conditions where faecal decay rates were greatest, whilst grasses appeared to benefit from faeces under dry conditions. Whilst growth of grasses and soil microbial biomass were stimulated by faecal addition, the depth of the extensive moss layer that is typical of tundra ecosystems was significantly reduced in fouled plots four years after faecal addition. The greatest reduction in moss depth occurred where fouling increased soil microbial biomass most, suggesting that enhanced decomposition of moss by a more abundant microbial community may have caused the reduced moss layer depth in fouled plots. Our field experiment demonstrates that by the production of faeces alone, vertebrate herbivores greatly impact on both above‐ and belowground components of tundra ecosystems and in doing so manipulate their own food supply. Our findings verify the assertion that grazing is of fundamental importance to tundra ecosystem productivity, and support the hypothesis that herbivory is instrumental in promoting grasses whilst suppressing mosses. The widely observed inverse relationship between grass and moss abundance in the field may therefore reflect the long history of plant‐herbivore interactions in tundra ecosystems.
Scale dependence of diversity measures in a leaf‐litter ant assemblage
Authors: Leponce Maurice , Theunis Laurence , Delabie Jacques H. C. , Roisin Yves
Published: March 2004

A reliable characterization of community diversity and composition, necessary to allow inter‐site comparisons and to monitor changes, is especially difficult to reach in speciose invertebrate communities. Spatial components of the sampling design (sampling interval, extent and grain) as well as temporal variations of species density affect the measures of diversity (species richness S, Buzas and Gibson's evenness E and Shannon's heterogeneity H). Our aim was to document the small‐scale spatial distribution of leaf litter ants in a subtropical dry forest of the Argentinian Chaco and analyze how the community characterization was best achieved with a minimal sampling effort. The work was based on the recent standardized protocol for collecting ants of the leaf litter (“A.L.L.”: 20 samples at intervals of 10 m). To evaluate the consistency of the sampling method in time and space, the selected site was first subject to a preliminary transect, then submitted after a 9‐month interval to an 8‐fold oversampling campaign (160 samples at interval of 1.25 m). Leaf litter ants were extracted from elementary 1 m2 quadrats with Winkler apparatus. An increase in the number of samples collected increased S and decreased E but did not affect much H. The sampling interval and extent did not affect S and H beyond a distance of 10 m between samples. An increase of the sampling grain had a similar effect on S than a corresponding increase of the number of samples collected, but caused a proportionaly greater increase of H. The density of species m−2 varied twofold after a 9‐month interval; the effect on S could only be partially corrected by rarefaction. The measure of species numerical dominance was little affected by the season. A single standardized A.L.L. transect with Winkler samples collected <45% of the species present in the assemblage. All frequent species were included but their relative frequency was not always representative. A log series distribution of species occurrences was oberved. Fisher's α and Shannon's H were the most appropriate diversity indexes. The former was useful to rarefy or abundify S and the latter was robust against sample size effects. Both parametric and Soberón and Llorente extrapolation methods outperformed non‐parametric methods and yielded a fair estimate of total species richness along the transect, a minimum value of S for the habitat sampled.
The region effect on mesoscale plant species richness between eastern Asia and eastern North America
Authors: E. Ricklefs Robert , Qian Hong , S. White Peter
Published: March 2004

The greater number of plant species in temperate eastern Asia compared to eastern North America has been ascribed to both local environment and regional characteristics, but the relative contributions of each have not been resolved. In this analysis, we related species richness of flowering plants in mesoscale floras (<104 km2) dominated by temperate forest vegetation to area, elevation, latitude, and several climate variables. When analyses were conducted separately within each region, area and, in eastern Asia, elevation, were the primary determinants of species richness. It appears that the number of species in mesic temperate floras within these regions is largely unrelated to the relatively narrow range of local climate factors associated with these floras. Analysis of covariance of the logarithm of species richness with the logarithm of area (b=0.148) and climate measurements as independent variables revealed a region effect, with species richness in eastern Asia exceeding that in eastern North America by 0.294 log10 units, or a factor of 2.0. Similar regional differences in species richness were apparent in floras compiled from larger areas. Understanding differences in plant species richness between regions requires consideration of regional influences, whose effects should be tested in comparative analyses based on floristic surveys of ecologically characterized small areas.
Reassessing the role of defensin in the innate immune response of the mosquito, Aedes aegypti
Authors: Bartholomay L. C. , Fuchs J. F. , Cheng L.‐L. , Beck E. T. , Vizioli J. , Lowenberger C. , Christensen B. M.
Published: March 2004

Defensin is the predominant inducible immune peptide in Aedes aegypti. In spite of its activity against Gram‐positive bacteria in vitro, defensin expression is detected in mosquitoes inoculated with Gram‐positive or negative bacteria, or with filarial worms. Defensin transcription and expression are dependent upon bacterial dose; however, translation is inconsistent with transcription because peptide is detectable only in mosquitoes inoculated with large doses. In vitro translation assays provide further evidence for post‐transcriptional regulation of defensin. Clearance assays show that a majority of bacteria are cleared before defensin is detected. In gene silencing experiments, no significant difference in mortality was observed between defensin‐deficient and control mosquitoes after bacteria inoculation. These studies suggest that defensin may have an alternative function in mosquito immunity.
DNA methylation in insects
Authors: Field L. M. , Lyko F. , Mandrioli M. , Prantera G.
Published: March 2004

Cytosine DNA methylation has been demonstrated in numerous eukaryotic organisms and has been shown to play an important role in human disease. The function of DNA methylation has been studied extensively in vertebrates, but establishing its primary role has proved difficult and controversial. Analysing methylation in insects has indicated an apparent functional diversity that seems to argue against a strict functional conservation. To investigate this hypothesis, we here assess the data reported in four different insect species in which DNA methylation has been analysed more thoroughly: the fruit fly Drosophila melanogaster, the cabbage moth Mamestra brassicae, the peach‐potato aphid Myzus persicae and the mealybug Planococcus citri.
Synchronization of Plodia interpunctella lepidopteran cells and effects of 20‐hydroxyecdysone
Authors: Siaussat D. , Mottier V. , Bozzolan F. , Porcheron P. , Debernard S.
Published: March 2004

We have investigated the molecular and cellular mechanisms involved in the control of insect cell cycle by 20‐hydroxyecdysone (20E) using the IAL‐PID2 cell line established from imaginal wing discs of Plodia interpunctella. We first defined conditions for use of hydroxyurea, a reversible inhibitor of DNA synthesis, in order to synchronize the IAL‐PID2 cells in their division cycle. A high degree of synchrony was reached when cells were exposed to two consecutive hydroxyurea treatments at 1 mm for 36 h spaced 16 h apart. Under these conditions, flow cytometry analysis demonstrated that 20E at 10−6 m induced an inhibition of cell growth by an arrest of 90% of the cells in G2/M phase. Using cDNA probes specifically designed from E75 and HR3 nuclear receptors of Plodia interpunctella, we showed that PiE75 and PHR3 were highly induced by 20E through S and G2 phases with maximal enhancement just before the G2/M arrest of cells. These findings suggest that PiE75 and PHR3 could be involved in a 20E‐induced genetic cascade leading to G2/M arrest.
Work of Female Rural Doctors
Authors: Wainer Jo
Published: March 2004

Objective:  To identify the impact of family life on the ways women practice rural medicine and the changes needed to attract women to rural practice.

Design:  Census of women rural doctors in Victoria in 2000, using a self‐completed postal survey.

Setting: General and specialist practice.

Subjects: Two hundred and seventy‐one female general practitioners and 31 female specialists practising in Rural, Remote and Metropolitan Area Classifications 3–7. General practitioners are those doctors with a primary medical degree and without additional specialist qualifications.

Main outcome measure: Interaction of hours and type of work with family responsibilities.

Results: Generalist and specialist women rural doctors carry the main responsibility for family care. This is reflected in the number of hours they work in clinical and non‐clinical professional practice, availability for on‐call and hospital work, and preference for the responsibilities of practice partnership or the flexibility of salaried positions. Most of the doctors had established a satisfactory balance between work and family responsibilities, although a substantial number were overworked in order to provide an income for their families or meet the needs of their communities. Thirty‐six percent of female rural general practitioners and 56% of female rural specialists preferred to work fewer hours. Female general practitioners with responsibility for children were more than twice as likely as female general practitioners without children to be in a salaried position and less likely to be a practice partner. The changes needed to attract and retain women in rural practice include a place for everyone in the doctor's family, flexible practice structures, mentoring by women doctors and financial and personal recognition.

What this paper adds:   Women make up less than a quarter of the rural general practice workforce and an even smaller percentage of the specialist rural medical workforce. As a result their experiences are not well articulated in research on rural medical practice and their needs are not well represented in policies and programs for rural doctors. The incoming cohort of rural general practitioners has a majority of women and it is essential that the practice styles and needs of women doctors are understood in order to attract and retain women in rural medicine. This survey identifies some of the effects of family responsibilities on the work practices of female rural doctors and the changes needed to the structure of rural practice to include the way women work.
Rural Doctors’ Satisfaction in Japan: A Nationwide Survey
Authors: Matsumoto Masatoshi , Okayama Masanobu , Kajii Eiji
Published: March 2004

Objectives:  The purpose of this paper was to discover to what degree Japanese rural doctors are satisfied with various aspects of their jobs and lives, and to find out whether they intend to continue their rural careers.

Design:  Nationwide postal survey

Setting:  Public clinics or hospitals in municipalities that are authorised as ‘rural’ by the national government.

Subjects:  A total of 4896 doctors working for public clinics or hospitals.

Interventions:  Self‐evaluation questionnaires were mailed. The rural doctors were asked to evaluate their satisfaction with 19 items related to their job conditions and 10 items concerning life conditions, using a four‐point scale. They also were asked to evaluate their intent to stay in rural practice until retirement.

Results:  The response rate was 64%. Overall, rural doctors were satisfied with both their work and life conditions. However, only 27% of respondents hoped to continue rural practice beyond the usual age of retirement. Among job‐related items, continuing medical education and interactions with municipal governments were rated as least satisfactory. Among lifestyle‐related items, duration of holidays and workload were unsatisfactory. Subgroup analysis revealed male doctors showed greater intent to stay in rural practice. Doctors aged > 50 years were more satisfied with most aspects of their job and lifestyle than younger doctors. A strong correlation was found between the degree of intent to stay and several items such as interactions with municipal government, human interactions salary and job fulfilment.

Conclusions:  Strategies, based on the results of this survey, should be implemented. Particularly in Japan, positive interaction between doctors and municipal governments is crucial.

What this paper adds:   Though rural doctors in Japan in general were satisfied with their lifestyle and work conditions, they have low intentions to stay in rural areas. Among the various factors that can cause this dissociation between satisfaction and intention to stay, doctors’ interactions with municipal governments play a pivotal role.
Psychosocial Investigation of Individual and Community Responses to the Experience of Ovine Johne's Disease in Rural Victoria
Authors: Hood Bernadette , Seedsman Terence
Published: March 2004

Objective:  This paper explores the psychosocial outcomes for individuals and communities in rural Victoria who experienced the outbreak of Ovine Johne's Disease (OJD).

Design:  The study uses a qualitative methodology to analyse the minutes of evidence provided by the inquiry into the control of OJD to identify the psychosocial events, experiences and outcomes associated with the control of this outbreak. The inquiry was undertaken by the Environment and Natural Resources Committee of the Victorian State Government.

Setting:  Public hearings were undertaken by the committee across several rural Victorian communities and the state capital, Melbourne.

Subjects:  The transcripts detail 136 submissions from 98 individuals and 23 organisations.

Outcome measures:  The analysis aimed to provide insight into the impact of the disease on individuals and communities and also to explore the factors individuals perceived as associated with these outcomes.

Results:  While the paper identifies that aspects of stock loss associated with the outbreak caused substantial emotional and economic distress, for farmers the most significant finding was the impact of the government control program on individuals, families and rural communities. The control program was perceived as having very limited scientific credibility and its implementation was described as heartless, inflexible and authoritarian. Involvement with the program resulted in farmers reporting emotions, such as, trauma, shame, guilt and stigma. Families became discordant and the sense of community within rural townships fragmented. Psychological outcomes of grief, depression and anxiety emerged as prevalent themes within families and communities.

Conclusions:  These data highlight the need for significant attention to the management of rural disasters, such as, the OJD program.

What this paper adds:  There is an acknowledgement in the literature that rural disasters have a significant impact on the well‐being of individuals, families and communities. The major focus of the previous research has, however, been on the impact of economic losses with less recognition of the other psychosocial loss experiences that accompany the experience of rural disaster. This paper achieves a clear description of the experiences for individuals (trauma, stigma, sense of personal failure, loss of identity, diminished self esteem and family disruption) and communities (destroyed social cohesion, economic disharmony) caught up in the OJD disaster and explores the factors that individuals perceive as responsible for these outcomes. The mental health outcomes for individuals, such as, loss, grief and depression are also explored within this paper. This paper highlights the psychosocial complexity of the experience of rural disaster for individuals and communities significantly extending the current knowledge base in this area.
Activation of human macrophages by allogeneic islets preparations: inhibition by AOP‐RANTES and heparinoids
Authors: Sigrist Séverine , Oberholzer José , Bohbot Alain , Esposito Guy , Mandes Karim , Lamartine Roger , Toso Christian , Bucher Pascal , Pinget Michel , Kessler Laurence
Published: March 2004

During transplantation, pancreatic islets release chemokines which promote macrophage attraction, hampering engraftment of islets. The aim of this study was to modulate chemotaxis and the immune response of human macrophages induced by islets. Human monocyte‐derived macrophages of healthy subjects were exposed to supernatants of human islets. Chemotaxis, tumour necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) release were evaluated. To modulate migration, human macrophages were incubated in the presence of aminooxypentane‐regulated on activation, normal, T‐cell expressed, and secreted (AOP‐RANTES), a potent antagonist of CCR5. Chemotactic activity of islets supernatant was modulated by the addition of heparin or heparinoids [pentosan and calix[8S]arene (C8S)]. AOP‐RANTES significantly reduced, in a dose‐dependent manner, macrophage chemotaxis and cytokine release induced by islets supernatant. The chemotactic index was reduced from 3·05 ± 0·27 to 0·71 ± 12, TNF‐α from 1205 ± 52 to 202 ± 12 pg/ml, and IL‐1β from 234 ± 12 to 10 ± 6 pg/ml. The trapping of chemokines by heparinoids reduced the chemotactic activity of islets supernatant from 3·05 ± 0·27 to 1·2 ± 0·1 with heparin or pentosan and to 1·72 ± 0·22 with C8S, and also decreased the TNF‐α release by human macrophages from 1205 ± 35 to 1000 ± 26 (C8S), 250 ± 21 (heparin) and 320 ± 19 (pentosan) pg/ml, and IL‐1β from 234 ± 13 to 151 ± 5 (C8S), 50 ± 3 (heparin) and 57 ± 4 (pentosan) pg/ml. In conclusion, AOP‐RANTES and heparinoids inhibit human macrophage activation and migration induced by islets supernatant.
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

The 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

A 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

Expression 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

An 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

Temporally 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

A 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

Plastid 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

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.