High-throughput screening identifies compounds that enhance lentiviral transduction

A difficulty in the field of gene therapy is the need to increase the susceptibility of hematopoietic stem cells (HSCs) to ex vivo genetic manipulation. To overcome this obstacle a high-throughput screen was performed to identify compounds that could enhance the transduction of target cells by lentiviral vectors. Of the 1280 compounds initially screened using the myeloid-erythroid-leukemic K562 cell line, 30 were identified as possible enhancers of viral transduction. Among the positive hits were known enhancers of transduction (camptothecin, etoposide and taxol), as well as the previously unidentified phorbol 12-myristate 13-acetate (PMA). The percentage of green fluorescent protein (GFP)-positive-expressing K562 cells was increased more than fourfold in the presence of PMA. In addition, the transduction of K562 cells with a lentiviral vector encoding fVIII was four times greater in the presence of PMA as determined by an increase in the levels of provirus in genetically modified cells. PMA did not enhance viral transduction of all cell types (for example, sca-1(+) mouse hematopoietic cells) but did enhance viral transduction of human bone marrow-derived CD34(+) cells. Notably, the percentage of GFP-positive CD34(+) cells was increased from 7% in the absence of PMA to greater than 22% in the presence of 1 nM PMA. PMA did not affect colony formation of CD34(+) cells or the expression of the hematopoietic markers CD34 and CD45. These data demonstrate that high-throughput screening can be used to identify compounds that increase the transduction efficiency of lentiviral vectors, identifying PMA as a potential enhancer of lentiviral HSC transduction.

Apathy and cortical atrophy in Alzheimer's disease

OBJECTIVES

Apathy has been reported as the most prevalent behavioural symptom experienced in Alzheimer's disease (AD), associated with greater functional decline and caregiver distress. The aim of the current study was to investigate structural correlates of apathy in AD using magnetic resonance imaging (MRI) regional volume and regional cortical thickness measures.

METHODS

Semi-structured interviews were conducted with 111 AD patients and their caregivers as part of the European multi-centre study AddNeuroMed. Apathy was measured using the apathy domain of the Neuropsychiatric Inventory (NPI). All AD patients were scanned using a 1.5T MRI scanner and the images analysed using an automated analysis pipeline.

RESULTS

We found apathy to be the most prevalent neuropsychiatric symptom occurring in 57% of patients. Apathetic patients had significantly greater cortical thinning in left caudal anterior cingulate cortex (ACC) and left lateral orbitofrontal cortex (OFC), as well as left superior and ventrolateral frontal regions, than those without apathy symptoms.

CONCLUSIONS

Apathy is mediated by frontocortical structures but this is specific to the left hemisphere at least for patients in the mild to moderate stages of AD.

The psychosocial vulnerability model of hostility as a predictor of coronary heart disease in low-income African Americans

The current study examined social support and stress as mediators of the hostility-coronary heart disease (CHD) relationship as suggested by the psychosocial vulnerability model in a sample of low-income African Americans. Among 95 CHD patients and 30 healthy controls, hostility was negatively correlated with social support, but was not related to minor stress. CHD patients endorsed higher levels of hostility; however, the relationship between hostility and CHD status was diminished once stress and social support were included in the model. This study lends partial support for the psychosocial vulnerability model of hostility in African Americans, but suggests that the relationship between hostility and stress may be impacted by socioeconomic status.

Changes in composition, structure and aboveground biomass over seventy-six years (1930-2006) in the Black Rock Forest, Hudson Highlands, southeastern New York State

We sought to quantify changes in tree species composition, forest structure and aboveground forest biomass (AGB) over 76 years (1930-2006) in the deciduous Black Rock Forest in southeastern New York, USA. We used data from periodic forest inventories, published floras and a set of eight long-term plots, along with species-specific allometric equations to estimate AGB and carbon content. Between the early 1930s and 2000, three species were extirpated from the forest (American elm (Ulmus americana L.), paper birch (Betula papyrifera Marsh.) and black spruce (Picea mariana (nigra) (Mill.) BSP)) and seven species invaded the forest (non-natives tree-of-heaven (Ailanthus altissima (Mill.) Swingle) and white poplar (Populus alba L.) and native, generally southerly distributed, southern catalpa (Catalpa bignonioides Walt.), cockspur hawthorn (Crataegus crus-galli L.), red mulberry (Morus rubra L.), eastern cottonwood (Populus deltoides Bartr.) and slippery elm (Ulmus rubra Muhl.)). Forest canopy was dominated by red oak and chestnut oak, but the understory tree community changed substantially from mixed oak-maple to red maple-black birch. Density decreased from an average of 1500 to 735 trees ha(-1), whereas basal area doubled from less than 15 m(2) ha(-1) to almost 30 m(2) ha(-1) by 2000. Forest-wide mean AGB from inventory data increased from about 71 Mg ha(-1) in 1930 to about 145 Mg ha(-1) in 1985, and mean AGB on the long-term plots increased from 75 Mg ha(-1) in 1936 to 218 Mg ha(-1) in 1998. Over 76 years, red oak (Quercus rubra L.) canopy trees stored carbon at about twice the rate of similar-sized canopy trees of other species. However, there has been a significant loss of live tree biomass as a result of canopy tree mortality since 1999. Important constraints on long-term biomass increment have included insect outbreaks and droughts.

Attitudes Toward Health Care Providers and Appointment Attendance in HIV/AIDS Patients

Patients with HIV/AIDS are likely to have numerous interactions with health care providers (HCPs) during the course of their disease. Research has shown that satisfaction with one's HCP is related to better medication adherence in patients with HIV/AIDS. Although a patient's attitude toward his or her HCP is important, little has been done to assess how it relates to appointment attendance. The current study assessed how attitudes toward HCPs as well as social support and depression relate to outpatient appointment attendance. Further, this study used a newly developed, psychometrically valid scale to assess specific patient attitudes toward HCPs including those related to disease stigma. Participants were predominantly low-income African American men (N = 109) recruited from a public southern HIV clinic. Analyses indicated that attitudes toward HIV HCPs, social support, and medication status but not depression or satisfaction with social support were associated with appointment attendance.

A stage-targeted physical activity intervention among a predominantly African-American low-income primary care population

PURPOSE

To examine the efficacy of a stage-targeted physical activity intervention among low-income African-Americans.

METHODS

207 participants were randomly assigned to groups and administered baseline measures. Intervention participants were mailed stage-targeted physical activity information, whereas control participants received low-sodium diet brochures. Measures were readministered by phone 1 and 6 months later, with response rates of 69% and 46%, respectively.

RESULTS

69% of participants were African-American and 64% had a monthly household income of < $1000. A doubly-multivariate analysis of variance indicated that intervention participants reported more physical activity than control participants at 1 month (F(1, 204) = 4.03, p < .05). Unlike control participants, intervention participants reported significant stage progression at 1 month, according to a McNemar chi2 test. Gains attenuated by 6 months.

CONCLUSIONS

The current study supports the use of this intervention among low-income African-Americans. Limitations include use of self-report measures and small sample size.

Components of ecosystem evaporation in a temperate coniferous rainforest, with canopy transpiration scaled using sapwood density

Here we develop and test a method to scale sap velocity measurements from individual trees to canopy transpiration (E(c)) in a low-productivity, old-growth rainforest dominated by the conifer Dacrydium cupressinum. Further, E(c) as a component of the ecosystem water balance is quantified in relation to forest floor evaporation rates and measurements of ecosystem evaporation using eddy covariance (E(eco)) in conditions when the canopy was dry and partly wet. Thermal dissipation probes were used to measure sap velocity of individual trees, and scaled to transpiration at the canopy level by dividing trees into classes based on sapwood density and canopy position (sheltered or exposed). When compared with ecosystem eddy covariance measurements, E(c) accounted for 51% of E(eco) on dry days, and 22% of E(eco) on wet days. Low transpiration rates, and significant contributions to E(eco) from wet canopy evaporation and understorey transpiration (35%) and forest floor evaporation (25%), were attributable to the unique characteristics of the forest: in particular, high rainfall, low leaf area index, low stomatal conductance and low productivity associated with severe nutrient limitation.

Attitudes toward HIV Health Care Providers scale: development and validation

Patient attitudes toward their health care providers can play an important role in determining health behavior change. The frequency of contact with health care professionals and disease stigma makes assessing patients' perception of this relationship of particular interest in an HIV medical population. While past general satisfaction and attitude tools have been used to assess this construct, there is a need for an assessment tool specific to patient attitudes in an HIV setting. This study was designed to validate the Attitudes toward HIV Health Care Provider scale (AHHCP) in an HIV medical population. Principal components analysis of the AHHCP yielded a two-factor structure accounting for 53.3% of the total variance in attitudes toward health care providers. The two factors represented items concerning Professionalism and Emotional Support. The AHHCP was found to have good internal consistency (0.92) and convergent validity with a measure of patient satisfaction (r = 0.59). The results of the present study suggest that the AHHCP is a reliable and valid instrument for use in assessing patient attitudes toward their health care providers.

Use of the Beck Depression Inventory-II with African American primary care patients

The Beck Depression Inventory-II (BDI-II) is one of the most common self-report instruments used for depression screening. However, there is a lack of research examining the effectiveness of this instrument in detecting depression in an African American primary care sample. The current study included 220 African American primary care patients who completed the BDI-II and were administered a diagnostic interview to establish depressive diagnoses. Results indicated that depressed patients demonstrated significantly greater BDI-II total scores compared to non-depressed patients. The recommended cutoff score of 14 for screening for depression appears to be appropriate for African American patients in the primary care setting. This cutoff yielded sensitivity of 87.7% and specificity of 83.9%. Positive predictive value of the BDI-II was .70, and negative predictive value was .94. Similar to findings with predominantly Caucasian samples, current results suggest the BDI-II is an appropriate and accurate instrument to use for depression screening among African American primary care patients.

Response of photosynthesis in second-generation Pinus radiata trees to long-term exposure to elevated carbon dioxide partial pressure

Second-generation Pinus radiata D. Don trees, propagated from cuttings of 4-year-old trees previously grown at ambient (36 Pa) and elevated (65 Pa) CO2 partial pressure (Ca) were grown under the same conditions in open-top chambers for a further year. As cuttings of the original trees, these second-generation trees were physiologically the same age as the first-generation trees with the only difference between the two being size. This allowed us to test the effects of tree size independently of age or duration of exposure. Total non-structural carbohydrate concentration, area-based nitrogen concentration, leaf mass per unit area and chlorophyll concentration measured in three foliage age cohorts were unaffected by either age or Ca. There were no signs of photosynthetic down-regulation in trees grown at elevated Ca. When measured at the growth Ca, photosynthetic rate in young needles during summer, autumn and spring was 34, 43 and 38% higher, respectively, in trees grown at elevated Ca than in trees grown at ambient Ca. In older needles, the corresponding photosythetic rate increases were 26, 47 and 49%. Water-use efficiency, determined by stable carbon isotope analysis, was 49% higher in foliage in the elevated Ca treatment than in foliage in the ambient Ca treatment. This increase was entirely due to photosynthetic enhancement, because stomatal conductance did not differ between treatments. We conclude that down-regulation of photosynthesis at elevated Ca is related to tree size rather than tree age or duration of exposure, and that enhanced photosynthetic rates can be maintained while sink strength is high enough to use the excess photosynthates.elevated CO2, needle age, photosynthetic down-regulation, photosynthetic enhancement, sink strength, water-use efficiency.

Sapwood development in Pinus radiata trees grown for three years at ambient and elevated carbon dioxide partial pressures

Clonal trees of Pinus radiata D. Don were grown in open-top chambers at a field site in New Zealand for 3 years at ambient (37 Pa) or elevated (65 Pa) carbon dioxide (CO2) partial pressure. Nitrogen (N) was supplied to half of the trees in each CO2 treatment, at 15 g N m-2 in the first year and 60 g N m-2 in the subsequent 2 years (high-N treatment). Trees in the low-N treatment were not supplied with N but received the same amount of other nutrients as trees in the high-N treatment. In the first year, stem basal area increased more in trees growing at elevated CO2 partial pressure and high-N supply than in control trees, suggesting a positive interaction between these resources. However, the relative rate of growth became the same across trees in all treatments after 450 days, resulting in trees growing at elevated CO2 partial pressure and high-N supply having larger basal areas than trees in the other treatments. Sapwood N content per unit dry mass was consistently about 0.09% in all treatments, indicating that N status was not suppressed by elevated CO2 partial pressure. Thus, during the first year of growth, an elevated CO2 partial pressure enhanced carbon (C) and N storage in woody stems, but there was no further stimulus to C and N deposition after the first year. The chemical composition of sapwood was unaffected by elevated CO2 partial pressure, indicating that no additional C was sequestered through lignification. However, independent of the treatments, early wood was 13% richer in lignin than late wood. Elevated CO2 partial pressure decreased the proportion of sapwood occupied by the lumina of tracheids by up to 12%, indicating increased sapwood density in response to CO2 enrichment. This effect was probably a result of thicker tracheid walls rather than narrower lumina.

Responses of transpiration and photosynthesis to reversible changes in photosynthetic foliage area in western red cedar (Thuja plicata) seedlings

Experiments were conducted on 1-year-old western red cedar (Thuja plicata Donn.) seedlings to determine the response of illuminated foliage to reversible changes in total photosynthetic foliage area (L(A)). Reductions in L(A) were brought about by either shading the lower foliage or by reducing the ambient CO2 concentration (c(a)) of the air surrounding the lower part of the seedling. In the latter case, the vapor pressure was also changed so that transpiration rates (E) could be manipulated independently of photosynthetic rates (A). We hypothesized that following such treatments, short-term compensatory changes would occur in stomatal conductance (g(s)) and A of the remaining foliage. These changes would occur in response to hydraulic signals generated by changes in the water potential gradient rather than changes in the distribution of sources and sinks of carbon within the seedling. When a portion of the foliage was shaded, there was an immediate reduction in whole-seedling E and a concomitant increase in g(s), A and E in the remaining illuminated foliage. However, the intercellular CO2 concentration did not change. These compensatory effects were fully reversed after the shade was removed. When the lower foliage A was reduced to < 0 micromol m-2 s-1, by shading or lowering c(a), and E was either unchanged or increased (by adjusting the vapor pressure deficit), there was no significant increase in g(s) and A in the remaining foliage. We conclude that compensatory responses in illuminated foliage occur only when reductions in L(A) are accompanied by a reduction in whole-plant E. The relationship between the reduction in whole-seedling E and the increase in A is highly linear (r2 = 0.68) and confirms our hypothesis of the strong regulation of g(s) by hydraulic signals generated within the seedling. We suggest that the mechanism of the compensatory effects is a combination of both increased CO2 supply, resulting from increased g(s), and a response of the rate of carboxylation, possibly related to the activity of Rubisco.

Molecules with shape memory based on restricted rotation

[reaction--see text] Diimide 1 and octaimide 2 both adopt two stable conformations at room temperature as a result of restricted rotation about two C(aryl)-N(imide) single bonds, a compact "folded" and an open "unfolded" structure. Predictable ratios of folded and unfolded rotamers can be achieved by heating in solvents of appropriate polarity as measured by the Reichardt's parameter (E(T30)). On cooling to room temperature, the resulting conformational changes are "locked in" as restricted rotation is reestablished.

A social cognitive model for health education/health promotion practice

AIM

To investigate the place and validity of contemporary social cognitive models for health education practice in nursing settings and, in doing so, develop and put forward a specific model for this purpose.

BACKGROUND/RATIONALE

The last decade or so has seen a marked increase in the amount of health educational/health promotional activities that nurses are expected to undertake. This has followed on from concerted calls to make health education a familiar and recognized part of nursing practice. Despite this, past and current evidence identifies that nurses have been, and continue to be, ineffective and inconsistent health education practitioners. Where health education activity does take place it tends to centre specifically on social cognitive behavioural change strategies. Subsequently, it is argued here that any failure on the part of nurses successfully to apply health educational initiatives into practice has been compounded by the lack of any nursing-specific social cognitive model process. This paper seeks to redress this imbalance by putting forward the case for such a model, developing it, and demonstrating how it can be incorporated into the practice setting.

METHOD

A systematic review of the literature has been conducted and the article draws upon this in order to develop an evolving theoretical perspective for health education practice. The proposed model has evolved from this new perspective. Development of this model has drawn on contemporary social cognitive behavioural models--using them as a means to develop a further conceptual framework for nursing.

CONCLUSION

Social cognitive behavioural models are valuable tools that nurses can incorporate routinely into existing frameworks of practice. The proposed model is designed to make the adoption of health-related behavioural change in clients easier and more realistic. If the current situation continues whereby social cognitive behavioural models are not adopted as a concerted and routine part of nursing practice, then nursing may well continue to fall behind other health professions in the discipline of health education.

A stage planning programme model for health education/health promotion practice

AIM

To investigate the validity of a stage planning programme model for health education/health promotion practice in nursing settings and to develop a specific model for this purpose. Background/rationale. The last decade or so has seen a marked increase in the amount of health educational/health promotional activities that nurses are expected to undertake. This has followed concerted calls to make health promotion a familiar and recognized part of nursing practice. Despite this, however, current health-related practices are still unstructured, haphazard and under-evaluated. This state of affairs is further compounded by the lack of any generic and systematic nursing planning process model by which health education/health promotion programmes are applied in practice. This paper puts forward the case for such a model, develops it, and demonstrates its possible application in clinical settings.

METHOD

A systematic literature review was conducted in order to develop a new theoretical perspective for health promotion/health education nursing practice. The proposed model has evolved from this new perspective. The process of developing this model has drawn on existing contemporary planning models--using them as a means to develop a conceptual framework. Consequently, the proposed model seeks to critique, adapt and adopt some of their components within a nursing context.

CONCLUSION

If the current situation continues, in which planning process models are not adopted as a routine part of practice, then nursing may well remain a "bystander" in health promotion/health education.

Canopy position and needle age affect photosynthetic response in field-grown Pinus radiata after five years of exposure to elevated carbon dioxide partial pressure

Photosynthesis of tree seedlings is generally enhanced during short-term exposure to elevated atmospheric CO2 partial pressure, but longer-term studies often indicate some degree of photosynthetic adjustment. We present physiological and biochemical evidence to explain observed long-term photosynthetic responses to elevated CO2 partial pressure as influenced by needle age and canopy position. We grew Pinus radiata D. Don. trees in open-top chambers for 5 years in sandy soil at ambient (36 Pa) and elevated (65 Pa) CO2 partial pressures. The trees were well watered and exposed to natural light and ambient temperature. In the fourth year of CO2 exposure (fall 1997), when foliage growth had ceased for the year, photosynthetic down-regulation was observed in 1-year-old needles, but not in current-year needles, suggesting a reduction in carbohydrate sink strength as a result of increasing needle age (Turnbull et al. 1998). In 5-year-old trees (spring 1997), when foliage expansion was occurring, photosynthetic down-regulation was not observed, reflecting significantly large sinks for carbohydrates throughout the tree. Net photosynthesis was stimulated by 79% in trees growing in elevated CO2 partial pressure, but there was no significant effect on photosynthetic capacity or Rubisco activity and concentration. Current-year needles were more responsive to elevated CO2 partial pressure than 1-year-old needles, exhibiting larger relative increases in net photosynthesis to elevated CO2 partial pressure (98 versus 64%). Lower canopy and upper canopy leaves exhibited similar relative responses to growth in elevated CO2 partial pressure. However, needles in the upper canopy exhibited higher net photosynthesis, photosynthetic capacity, and Rubisco activity and concentration than needles in the lower canopy. Given that the ratio of mature to juvenile foliage mass in the canopy will increase as trees mature, we suggest that trees may become less responsive to elevated CO2 partial pressure with increasing age. We conclude that tree response to elevated CO2 partial pressure is based primarily on sink strength and not on the duration of exposure.

Photosynthesis and light-use efficiency by plants in a Canadian boreal forest ecosystem

Measurements of the photosynthetic response to midsummer irradiance were made for 11 species representing the dominant trees, understory shrubs, herbaceous plants and moss species in an old black spruce (Picea mariana (Mill.) B.S.P.) boreal forest ecosystem. Maximum rates of photosynthesis per unit foliage area at saturating irradiance, A(max), were highest for aspen (Populus tremuloides Michx.), reaching 16 micromol m(-2) s(-1). For tamarack (Larix laricina (Du Roi) K. Kock) and P. mariana, Amax was only 2.6 and 1.8 micromol m(-2) s(-1), respectively. Values of A(max) for understory shrubs and herbaceous plants were clustered between 9 and 11 micromol m(-2) s(-1), whereas A(max) of feather moss (Pleurozium schreberi (Brid.) Mitt.) reached only 1.9 micromol m(-2) s(-1). No corrections were made for differences in shoot structure, but values of photosynthetic light-use efficiency were similar for most species (70-80 mmol CO2 mol(-1)); however, they were much lower for L. laricina and P. mariana (15 mmol CO2 mol(-1)) and much higher for P. schreberi (102 m;mol CO2 mol(-1)). There was a linear relationship between Amax and foliage nitrogen concentration on an area basis for the broad-leaved species in the canopy and understory, but the data for P. mariana, L. laricina and P. schreberi fell well below this line. We conclude that it is not possible to scale photosynthesis from leaves to the canopy in this ecosystem based on a single relationship between photosynthetic rate and foliage nitrogen concentration.

Responses of leaf respiration to temperature and leaf characteristics in three deciduous tree species vary with site water availability

We measured responses of leaf respiration to temperature and leaf characteristics in three deciduous tree species (Quercus rubra L., Quercus prinus L. and Acer rubrum L.) at two sites differing in water availability within a single catchment in the Black Rock Forest, New York. The response of respiration to temperature differed significantly among the species. Acer rubrum displayed the smallest increase in respiration with increasing temperature. Corresponding Q(10) values ranged from 1.5 in A. rubrum to 2.1 in Q. prinus. Dark respiration at ambient air temperatures, expressed on a leaf area basis (Rarea), did not differ significantly between species, but it was significantly lower (P < 0.01) in trees at the wetter (lower) site than at the drier (upper) site (Q. rubra: 0.8 versus 1.1 micromol m(-2) s(-1); Q. prinus: 0.95 versus 1.2 micromol m(-2) s(-1)). In contrast, when expressed on a leaf mass basis (R(mass)), respiration rates were significantly higher (P < 0.01) in A. rubrum (12.5-14.6 micromol CO(2) kg(-1) s(-1)) than in Q. rubra (8.6-9.9 micromol CO(2) kg(-1) s(-1)) and Q. prinus (9.2-10.6 micromol CO(2) kg(-1) s(-1)) at both the lower and upper sites. Respiration on a nitrogen basis (R(N)) displayed a similar response to R(mass). The consistency in R(mass) and R(N) between sites indicates a strong coupling between factors influencing respiration and those affecting leaf characteristics. Finally, the relationships between dark respiration and A(max) differed between sites. Trees at the upper site had higher rates of leaf respiration and lower A(max) than trees at the lower site. This shift in the balance of carbon gain and loss clearly limits carbon acquisition by trees at sites of low water availability, particularly in the case of A. rubrum.

Health education, behavioural change and social psychology: nursing's contribution to health promotion?

AIMS

To critically review the complex processes that underpin the modification of a client's health-related behaviour. This paper also seeks to contextualize the operational differences between health-educating and health-promoting activities - as a means of rationalizing current practice.

BACKGROUND

In "health promotional" encounters, there is a plethora of evidence that suggests that nurses work predominantly within a "traditional" preventative framework of practice. The prevalence of a culturally inherent biomedical framework, governing most nursing practice, tends to reduce health-related client interventions to little more than one-off, reductionist information-giving exercises. The expectation on clients to respond to and subsequently modify their health behaviour, when presented with such information, is unrealistic in most cases. Nurses are often unaware of the extremely complex human phenomena associated with modifying health-related behaviours and the resultant change processes. In nursing-related health encounters, the planned or unplanned intervention and the subsequent outcomes are mostly viewed within a too simplistic and superficial context.

DESIGN

A selective review of the relevant literature.

CONCLUSION

Where many nurses believe themselves to be health promotionalists, the likelihood is that they are instead more likely to be traditional health educationalists. Not that this is the main problem, in itself--but if nursing is to progress on this issue, it must first become more effective in delivering its current health education initiatives. Armed with further knowledge and understanding of their practices, health educators are far more likely to achieve a degree of success in their behavioural-change encounters as well as approach the intervention with a far more realistic expectation of outcome. Without this further understanding, it is argued that the integration of health educational initiatives into nursing practice will generally do little or nothing to change the health status of clients.

The case for researching the history of community nursing practice

Despite a flurry of interest in the 1980s, the adoption of a positivist, objective, scientific paradigm for nursing research has led to a rejection of the study of nursing history as a valid pursuit in recent years. In this article, it is argued that this is a precarious situation. By not examining the history of the profession, nursing -- and in particular community nursing -- undermines its efforts to validate itself within the wider health-care arena. Nursing must learn from the mistakes of the past, as well as the successes, but do so in a critical way that does not romanticize its history.

Plant growth in elevated CO2 alters mitochondrial number and chloroplast fine structure

With increasing interest in the effects of elevated atmospheric CO(2) on plant growth and the global carbon balance, there is a need for greater understanding of how plants respond to variations in atmospheric partial pressure of CO(2). Our research shows that elevated CO(2) produces significant fine structural changes in major cellular organelles that appear to be an important component of the metabolic responses of plants to this global change. Nine species (representing seven plant families) in several experimental facilities with different CO(2)-dosing technologies were examined. Growth in elevated CO(2) increased numbers of mitochondria per unit cell area by 1.3-2.4 times the number in control plants grown in lower CO(2) and produced a statistically significant increase in the amount of chloroplast stroma (nonappressed) thylakoid membranes compared with those in lower CO(2) treatments. There was no observable change in size of the mitochondria. However, in contrast to the CO(2) effect on mitochondrial number, elevated CO(2) promoted a decrease in the rate of mass-based dark respiration. These changes may reflect a major shift in plant metabolism and energy balance that may help to explain enhanced plant productivity in response to elevated atmospheric CO(2) concentrations.

Applying collaborative practice to health promotion

BACKGROUND

Since the publication of the Health of the Nation document in 1992, collaborative practice has been at the forefront of health service reform. While other professional groups have readily adopted health promotion and collaboration, the nursing profession has experienced difficulties in changing practice and some have resisted reform. The author examines the issues surrounding nursing's apparent hesitancy in adopting collaborative working practices.

CONCLUSION

To promote collaborative practice, nurses need to be aware of the range of teams and agencies involved in health promotion and acknowledge the client as an equal member of the team. However, better education, training and shared learning initiatives are essential to improve collaborative practice.

Amycolatopsis sacchari sp. nov., a moderately thermophilic actinomycete isolated from vegetable matter

The taxonomic position of a group of moderately thermophilic actinomycetes isolated from vegetable matter was determined using a suite of genotypic and phenotypic properties. The organisms were found to share a range of chemical and morphological markers typical of members of the genus Amycolatopsis. A representative of the group, strain K24T, formed a distinct phyletic line within the range of variation occupied by the genus Amycolatopsis in the 16S rDNA tree. The strains have many phenotypic properties in common and some of these distinguish the group from representatives of the validly described species of Amycolatopsis. It is clear from the combined datasets that the strains merit recognition as a new species of Amycolatopsis. The name proposed for the new species is Amycolatopsis sacchari; the type strain is K24T (= DSM 44468T = KCTC 9863T).

The role of community-based nurses in health promotion

It is the responsibility of all nurses to incorporate health promotional and health education activities into their professional roles. Much of the literature around this issue relates to the specific role of community-based nurses in the primary healthcare team, and identifies their unique position and responsibility for pioneering the universal acceptance and adoption of health-promoting practice. Community-based nurses are in a good position to commission health-related activities and integrate them into practice (Department of Health and Social Security, 1987; Department of Health, 1992, 1996). On the basis of this, one might expect that the results of studies in this area would identify evidence of good understanding, adoption, parity and support for such initiative among community professionals. However, many studies have identified a state of confusion, poor understanding, a lack of parity between professional groups, a lack of professional support and training, and haphazard implementation of such strategies (Dines, 1994; Russell, 1997). Inconsistency in study findings is problematic and tends to present a skewed picture of current practice. It is suggested that community-based nurses may benefit from a change in the way they view the implementation of health promotional practices, and that policy issues related to practice could be further clarified and enforced.

Using mass media within health-promoting practice: a nursing perspective

For some time health professionals have recognized the growing importance of utilizing mass media strategies as part of their health-promoting practice. The ever-evolving climate of technology and increasing reliance on mass communications has further reinforced the position of mass media initiatives. The enormous potential for mass media resources to reach certain audiences and influence their health-related behaviours has become particularly well established. Despite these facts, however, it is argued that the nursing profession has been less than pro-active in acknowledging, accommodating and adopting such practices. Consequently, the incorporation of health-related mass media initiatives into nursing's health-promotional role remains an elusive exercise. The maintenance of such a position, it is claimed, is potentially damaging for the profession as a whole. In light of this state of affairs, this paper seeks to review the literature surrounding the nature and processes of mass media strategies, their relevance to health promotion and nursing, how they are currently utilized and how they can be incorporated further into nursing practice. In conclusion, it is argued that nursing should seek to become a more active user of mass communication/media technology--especially in relation to its health-promotional practices.

'Naturalistic vs reductionistic approaches to health-related practice: opposing dichotomy or symbiotic partnership?'

Complementary therapies, within Health Service arenas, have traditionally been associated with 'naturalistic' approaches to health care provision rather than with 'reductionist' practices. Evidence does exist, however, that certain approaches to complementary therapies can exist comfortably within both camps. Subsequent debates within nursing literature, surrounding the place and validity of reductionist approaches to health care provision and their relationship with the 'counter-part' naturalistic (i.e. empowerment) approaches to health care, have existed for some time now. Naturalistic (inductive and interpretive) and reductionistic (deductive and fixed) classifications of health care provision have continued to be viewed, by many health care professionals, as apposite, divided and allopathic. This appears to be even more so recently where elements of reductionist health care have been portrayed in terms that serve to undervalue and undermine its contribution. This is whilst naturalistic approaches, in far more favourable terms, have gone on to be 'championed' by many health professions. This account sets out to investigate how this situation impacts upon the discipline of complementary therapies. It seeks to do so by defining the nature and purpose of these differing approaches - particularly within the boundaries of health promotion activities. It goes on to suggest that our current practices/viewpoints, related to these particular approaches, could be considered in themselves to be flawed, limiting and reductionist with a potential to unwittingly create a counterproductive practice ethic. As an alternative to this situation, it is suggested that by identifying the strengths and weaknesses of both stances it is possible to find common ground which marries together the more favourable aspects of these approaches. This can subsequently provide a clearer and more productive consensus for complementary therapies and other naturalistic-based practices to move forward.

Is there a place for epidemiology in nursing?

BACKGROUND

Epidemiological research is seen by many to have immense value in helping to determine the health of populations and in helping to plan and determine health service policy. Despite this it seems to be poorly understood and greatly underused by the nursing profession.

CONCLUSION

Epidemiological studies can potentially offer considerable benefits to the way nurses incorporate health-related practices into their professional role. Research also offers a valuable opportunity for the nursing profession to become more active in helping to determine health policy issues. This article explores the nature of the dilemmas surrounding nursing and epidemiology and argues that nursing might be better served by a more proactive role in this valuable research discipline.

What is the role of health promotion in nursing?

There is much confusion about the philosophical assumptions underlying nursing and health promotion. Effective health promotion strategies are based on the concepts of patient empowerment and the need for equal working relationships. The cultural climate of nursing may have to change if these principles are to be successfully adopted.

The relationship between health promotion and complementary therapies

The underlying philosophies of health promotion and complementary therapies are very closely related and, consequently, share many similarities; yet such similarities that exist between these two disciplines are rarely expressed, acknowledged or explored. It would be almost impossible to practice complementary therapies without incorporating elements of health promotion within them, whether this is done so knowingly, or not, by the practitioner. This account sets out to establish the nature of such a relationship and highlights the common advantages and dilemmas in recognizing such a relationship. It seeks to determine the validity of closer collaboration (between the two disciplines) in order to provide a collective consensus for like-minded nurses to move towards a more holistic and empowering paradigm. It concludes by suggesting that, in order to move the shared aims of health promotion and complementary therapies forward, closer ties need to be established, between the disciplines, and built upon.

The nature of health promotion in acute and community settings

Since the late 1980s, there has been a consistent call from nursing's advisory and legislative bodies to incorporate the discipline of health promotion into the nursing profession. On reflection, however, evidence indicates that despite these calls there has not been a universal uptake of health promotional activity into the profession. What is evident is that where health promotional activity does take place, it occurs more in the community than in the acute setting. This article sets out to explore the reasons for this. It suggests that certain current and future activities may help to further promote the universal adoption of health promotion within nursing practice.

Agglomeration inhibition reflected stone-forming activity during long-term potassium citrate therapy in calcium stone formers

OBJECTIVES

The agglomeration of preformed crystals of calcium oxalate has been hypothesized to be the rate-limiting step in renal stone-forming activity (SFA). The effect of urine on the in vitro inhibition of agglomeration of seed crystals of calcium oxalate monohydrate, designated [tm], has been used to monitor SFA in calcium oxalate stone formers (CaOxSF). The objective of the present study was to determine whether [tm] could be used to help monitor the long-term effectiveness of oral potassium citrate therapy (K-Cit-Rx) in CaOxSF.

METHODS

Clinic and radiographic (or ultrasound) reports were evaluated for 80 patients, aged 20 to 72 years, 55 men and 25 women, who were treated with oral K-Cit for recurrent calcium oxalate urolithiasis at the Ochsner Stone Clinic between January 1992 and July 1996. Seventy-five of these patients had at least one 24-hour citrate excretion rate of less than 3.0 mm/day before or after K-Cit-Rx. SFA graded on a scale of -2 to +2 by radiographic criteria was combined with information on stone passage to evaluate clinical stone status, and 24-hour urine collections were evaluated for volume, pH, calcium, citrate, uric acid, oxalate, creatinine, and [tm] on free diet before and after 6 to 53 months of K-Cit-Rx. Historical information on procedures performed for urolithiasis before and on K-Cit-Rx was also reviewed.

RESULTS

K-Cit-Rx resulted in increased urine pH (P <0.0001) and decreased calcium (P=0.0475), [tm] (P=0.0045), number of stones passed per year (P=0.0016), and remedial procedures per year (P <0.0001). Patients taking allopurinol in addition to K-Cit required higher doses (P <0.0001) of K-Cit to control their disease, had lower pretreatment urine pH (P=0.0493), and showed greater increase in urine citrate (P=0.0092) than those on K-Cit alone. Those taking high-dose K-Cit were younger (P=0.0363) and showed greater decrease in SFA (P=0.0005) than those taking lower doses. A small group of 10 medication refractory patients, who retained (n=9) or increased (n=1) their stone burden during K-Cit-Rx, was identified. Compared with the medication-responsive group, the refractory patients were older (P=0.0124), and had greatly increased SFA (P <0.0001) and higher (P=0.0347) urine pH before and during (P=0.0173) treatment (data not shown).

CONCLUSIONS

The data confirm that [tm] can be used not only to verify previously documented stone formation rate but also to help evaluate the long-term effectiveness of therapy. In this report, changes in [tm] after K-Cit-Rx reflected decreased stone formation rate and decreased remedial procedures.

Differences between descriptive and multivariate estimates of the impact of Chevron Corporation's Health Quest Program on medical expenditures

This investigation focused on alternative methods for evaluating the impact of Chevron Corporation's Health Quest Fitness Center program on medical expenditures, comparing descriptive and multivariate research designs. Many uncontrolled studies of corporate health management programs base estimates of program effectiveness on descriptive analyses such as Student's tests. Unlike more sophisticated multivariate analyses, descriptive analyses often produce biased estimates of program cost savings. To test alternative research design methods, the investigators compared inpatient and pharmacy expenditures for program participants and non-participants over a 2.5-year period, using descriptive and multivariate regression analyses. Results showed that compared with non-participants, expenditures for participants were significantly lower for subjects who used a Health Quest fitness center at least twice weekly. Previous descriptive studies suggested a much broader impact. The results underscore the need to use multivariate analyses when evaluating the financial impact of corporate health management programs, especially when randomization cannot be used to assign participation status.