Rapid neutrophil mobilization by VCAM-1+ endothelial cell-derived extracellular vesicles

AIMS

Acute myocardial infarction rapidly increases blood neutrophils (<2 h). Release from bone marrow, in response to chemokine elevation, has been considered their source, but chemokine levels peak up to 24 h after injury, and after neutrophil elevation. This suggests that additional non-chemokine-dependent processes may be involved. Endothelial cell (EC) activation promotes the rapid (<30 min) release of extracellular vesicles (EVs), which have emerged as an important means of cell-cell signalling and are thus a potential mechanism for communicating with remote tissues.

METHODS AND RESULTS

Here, we show that injury to the myocardium rapidly mobilizes neutrophils from the spleen to peripheral blood and induces their transcriptional activation prior to arrival at the injured tissue. Time course analysis of plasma-EV composition revealed a rapid and selective increase in EVs bearing VCAM-1. These EVs, which were also enriched for miRNA-126, accumulated preferentially in the spleen where they induced local inflammatory gene and chemokine protein expression, and mobilized splenic-neutrophils to peripheral blood. Using CRISPR/Cas9 genome editing, we generated VCAM-1-deficient EC-EVs and showed that its deletion removed the ability of EC-EVs to provoke the mobilization of neutrophils. Furthermore, inhibition of miRNA-126 in vivo reduced myocardial infarction size in a mouse model.

CONCLUSIONS

Our findings show a novel EV-dependent mechanism for the rapid mobilization of neutrophils to peripheral blood from a splenic reserve and establish a proof of concept for functional manipulation of EV-communications through genetic alteration of parent cells.

Hyperglycemia Induces Trained Immunity in Macrophages and Their Precursors and Promotes Atherosclerosis

BACKGROUND

Cardiovascular risk in diabetes remains elevated despite glucose-lowering therapies. We hypothesized that hyperglycemia induces trained immunity in macrophages, promoting persistent proatherogenic characteristics.

METHODS

Bone marrow-derived macrophages from control mice and mice with diabetes were grown in physiological glucose (5 mmol/L) and subjected to RNA sequencing (n=6), assay for transposase accessible chromatin sequencing (n=6), and chromatin immunoprecipitation sequencing (n=6) for determination of hyperglycemia-induced trained immunity. Bone marrow transplantation from mice with (n=9) or without (n=6) diabetes into (normoglycemic) Ldlr-/- mice was used to assess its functional significance in vivo. Evidence of hyperglycemia-induced trained immunity was sought in human peripheral blood mononuclear cells from patients with diabetes (n=8) compared with control subjects (n=16) and in human atherosclerotic plaque macrophages excised by laser capture microdissection.

RESULTS

In macrophages, high extracellular glucose promoted proinflammatory gene expression and proatherogenic functional characteristics through glycolysis-dependent mechanisms. Bone marrow-derived macrophages from diabetic mice retained these characteristics, even when cultured in physiological glucose, indicating hyperglycemia-induced trained immunity. Bone marrow transplantation from diabetic mice into (normoglycemic) Ldlr-/- mice increased aortic root atherosclerosis, confirming a disease-relevant and persistent form of trained innate immunity. Integrated assay for transposase accessible chromatin, chromatin immunoprecipitation, and RNA sequencing analyses of hematopoietic stem cells and bone marrow-derived macrophages revealed a proinflammatory priming effect in diabetes. The pattern of open chromatin implicated transcription factor Runt-related transcription factor 1 (Runx1). Similarly, transcriptomes of atherosclerotic plaque macrophages and peripheral leukocytes in patients with type 2 diabetes were enriched for Runx1 targets, consistent with a potential role in human disease. Pharmacological inhibition of Runx1 in vitro inhibited the trained phenotype.

CONCLUSIONS

Hyperglycemia-induced trained immunity may explain why targeting elevated glucose is ineffective in reducing macrovascular risk in diabetes and suggests new targets for disease prevention and therapy.

The Updated Neuroradiology Milestones: Synapsing from 1.0 to 2.0

The Accreditation Council for Graduate Medical Education is currently in the process of specialty-by-specialty revision of the Milestones. As a result, the Neuroradiology Milestones 2.0 Workgroup was created to refine a system of competency-based assessments for fellow educational growth and development. Strengths of the new Milestones include decreased complexity and uniformity within a subcompetency as it relates to a specific educational development trajectory. The Supplemental Guide serves to decrease clutter in the Milestones 2.0 document and provides a more practical resource for guidance. This article serves to review the history of the Neuroradiology Milestones, followed by a summary of the timeline of events and discussions of the workgroup for development of Neuroradiology Milestones 2.0 and a synopsis of major changes. The plan is for the updated Neuroradiology Milestones to take effect in 2021 or 2022 based on public commentary.

Diabetes and Metabolic Drivers of Trained Immunity

Accumulating evidence shows how diverse physiological functions, such as metabolism, immunity, tissue homeostasis, and hematopoiesis, are intricately and profoundly intertwined at multiple levels. This brief review will present evidence from a rapidly expanding field of immunometabolism, highlighting how cells that are relevant to processes at play in determining vascular health and disease can be programmed by changes in their metabolic environment. It will focus on how such changes can be imprinted or trained, particularly through epigenetic modifications, such that adaptations driven by metabolic signals can cause persistent changes in cell function, even after the original stimulus has been corrected or removed. Recognition of these processes and elucidation of the mechanisms underlying them stand to have far-reaching implications for the diagnosis and treatment of diabetes and related metabolic states.

Regenerative medicine, organ bioengineering and transplantation

Background

Organ transplantation is predicted to increase as life expectancy and the incidence of chronic diseases rises. Regenerative medicine-inspired technologies challenge the efficacy of the current allograft transplantation model.

Methods

A literature review was conducted using the PubMed interface of MEDLINE from the National Library of Medicine. Results were examined for relevance to innovations of organ bioengineering to inform analysis of advances in regenerative medicine affecting organ transplantation. Data reports from the Scientific Registry of Transplant Recipient and Organ Procurement Transplantation Network from 2008 to 2019 of kidney, pancreas, liver, heart, lung and intestine transplants performed, and patients currently on waiting lists for respective organs, were reviewed to demonstrate the shortage and need for transplantable organs.

Results

Regenerative medicine technologies aim to repair and regenerate poorly functioning organs. One goal is to achieve an immunosuppression-free state to improve quality of life, reduce complications and toxicities, and eliminate the cost of lifelong antirejection therapy. Innovative strategies include decellularization to fabricate acellular scaffolds that will be used as a template for organ manufacturing, three-dimensional printing and interspecies blastocyst complementation. Induced pluripotent stem cells are an innovation in stem cell technology which mitigate both the ethical concerns associated with embryonic stem cells and the limitation of other progenitor cells, which lack pluripotency. Regenerative medicine technologies hold promise in a wide array of fields and applications, such as promoting regeneration of native cell lines, growth of new tissue or organs, modelling of disease states, and augmenting the viability of existing ex vivo transplanted organs.

Conclusion

The future of organ bioengineering relies on furthering understanding of organogenesis, in vivo regeneration, regenerative immunology and long-term monitoring of implanted bioengineered organs.

Glutamine Links Obesity to Inflammation in Human White Adipose Tissue

While obesity and associated metabolic complications are linked to inflammation of white adipose tissue (WAT), the causal factors remain unclear. We hypothesized that the local metabolic environment could be an important determinant. To this end, we compared metabolites released from WAT of 81 obese and non-obese women. This identified glutamine to be downregulated in obesity and inversely associated with a pernicious WAT phenotype. Glutamine administration in vitro and in vivo attenuated both pro-inflammatory gene and protein levels in adipocytes and WAT and macrophage infiltration in WAT. Metabolomic and bioenergetic analyses in human adipocytes suggested that glutamine attenuated glycolysis and reduced uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) levels. UDP-GlcNAc is the substrate for the post-translational modification O-linked β-N-acetylglucosamine (O-GlcNAc) mediated by the enzyme O-GlcNAc transferase. Functional studies in human adipocytes established a mechanistic link between reduced glutamine, O-GlcNAcylation of nuclear proteins, and a pro-inflammatory transcriptional response. Altogether, glutamine metabolism is linked to WAT inflammation in obesity.

2379Endothelial cell derived extracellular vesicles mediate immune cell deployment from the spleen and transcriptional programming following acute myocardial infarction

Background

Acute myocardial infarction (AMI) induces transcriptional activation of monocyte en route to the injured myocardium, possibly through interactions involving plasma liberated extracellular vesicles (EVs), which are enriched for proteins and microRNAs (miRNAs) post-AMI. Neutrophils are the first immune cells to arrive at sites of injury and mediate further damage to the ischaemic myocardium. Here, we describe neutrophil-deployment from the spleen in AMI and by endothelial cell (EC) derived-EVs.

Methods

Patients presenting AMI provided informed consent as part of the Oxford Acute Myocardial Infarction Study (OxAMI). Plasma EV were isolated by differential ultra-centrifugation (120,000g, 2 hours) followed by washing and characterised for: morphology using transmission electron microscopy (TEM), size and concentration profiling by Nanoparticle Tracking Analysis, EV markers (TSG101, ALIX, CD9, HSP70) by western blot, and miRNAs by RT-qPCR. Mouse and human EC were used in vitro to derive EC-EV under control conditions or after inflammatory stimulation with tumour necrosis factor-alpha (TNF-α) (10ng/mL) and from CRISPR-edited miRNA-126 knock-out ECs. EC-EVs were tail vein injected into wild-type mice or exposed to primary human peripheral blood neutrophils in vitro.

Results

Patients presenting with AMI (N=15) have significantly more plasma EV at time of injury vs a 6-month follow-up measurement (2.2-fold more, P=0.008). Plasma EVs at the time of AMI presentation correlate significantly with the extent of ischaemic injury (R=0.046, P=0.006) and plasma neutrophils (R=0.37, P=0.017). Experimental AMI in wild-type mice induced a significant increase in peripheral blood neutrophils and a simultaneous reduction in splenic-neutrophils, suggesting splenic-neutrophil deployment (P=0.004). Human plasma EV are enriched for vascular cell adhesion molecule-1 (VCAM-1) and EC-associated miR-126 post-AMI (Akbar et al 2017). miRNA-126-mRNA targets are significantly over represented when compared to neutrophil Gene Ontology terms for: degranulation (P<0.001), activation (P<0.001), chemotaxis (P=0.008) and migration (P=0.008). Human and mouse EC release more EV after inflammatory stimulation and show enrichment for miRNA-126. CRISPR-edited miRNA-126 deficient human EC express more VCAM-1 (P<0.001) and release more EC-EVs (P<0.001). EC-EV exposure to primary human neutrophils alters inflammatory gene expression (IL-6 (P<0.05), CCL7 (P<0.001) and CCL18 (P<0.001)). EC-EV tail vein injected into wild-type mice mobilise splenic-neutrophils to peripheral blood (P<0.001).

Conclusions

Neutrophil deployment from the spleen is a novel finding in acute injury and interactions with EC-EV may mediate their splenic liberation and transcriptional programming following AMI, en route to the injured myocardium. The splenic neutrophil reserve may be a novel therapeutic target in AMI to modulate the inflammatory response before recruitment of cells to sites of injury.

Acknowledgement/Funding

British Heart Foundation Project Grant and Centre for Research Excellence Awards (RE/13/1/30181), Nuffield Benefaction for Medicine and ISSF

Differential Gene Expression in Macrophages From Human Atherosclerotic Plaques Shows Convergence on Pathways Implicated by Genome-Wide Association Study Risk Variants

Supplemental Digital Content is available in the text.

Objective—

Plaque macrophages are intricately involved in atherogenesis and plaque destabilization. We sought to identify functional pathways in human plaque macrophages that are differentially regulated in respect of (1) plaque stability and (2) lipid content. We hypothesized that differentially regulated macrophage gene sets would relate to genome-wide association study variants associated with risk of acute complications of atherosclerosis.

Approach and Results—

Forty patients underwent carotid magnetic resonance imaging for lipid quantification before endarterectomy. Carotid plaque macrophages were procured by laser capture microdissection from (1) lipid core and (2) cap region, in 12 recently symptomatic and 12 asymptomatic carotid plaques. Applying gene set enrichment analysis, a number of gene sets were found to selectively upregulate in symptomatic plaque macrophages, which corresponded to 7 functional pathways: inflammation, lipid metabolism, hypoxic response, cell proliferation, apoptosis, antigen presentation, and cellular energetics. Predicted upstream regulators included IL-1β, TNF-α, and NF-κB. In vivo lipid quantification by magnetic resonance imaging correlated most strongly with the upregulation of genes of the IFN/STAT1 pathways. Cross-interrogation of gene set enrichment analysis and meta-analysis gene set enrichment of variant associations showed lipid metabolism pathways, driven by genes coding for APOE and ABCA1/G1 coincided with known risk-associated SNPs (single nucleotide polymorphisms) from genome-wide association studies.

Conclusions—

Macrophages from recently symptomatic carotid plaques show differential regulation of functional gene pathways. There were additional quantitative relationships between plaque lipid content and key gene sets. The data show a plausible mechanism by which known genome-wide association study risk variants for atherosclerotic complications could be linked to (1) a relevant cellular process, in (2) the key cell type of atherosclerosis, in (3) a human disease-relevant setting.

Intravascular catheter migration: A cross-sectional and health-economic comparison of adhesive and subcutaneous engineered stabilisation devices for intravascular device securement

The Infusional Services Team at a large cancer centre in Belfast, Northern Ireland, performed a cross-sectional analysis of two catheter securement technologies to address an area of frequent, but underestimated concern – peripherally inserted central catheter migration and dislodgement. Healthcare practitioner and patient feedback, along with economic impact, were assessed. The costs associated with catheter replacement during the adhesive device group study period were calculated using an average cost per insertion, based on material costs required for the procedure. Other factors were the replacement cost of the adhesive engineered securement device with each dressing change. In the subcutaneous securement group, the material costs were adjusted for use of the subcutaneous device as it remained in situ for the duration of the catheters’ dwell time. This review found that subcutaneous securement offers both patient and facilities a safe, effective and economical alternative for device securement with patients who are unable to tolerate or have successful securement with adhesive securement devices. The use of subcutaneous devices provided for reduced risks for peripherally inserted central catheters in terms of dislodgement, migration or malposition, alleviating the potential risks to develop catheter-related thrombosis and device-related infection.

The relationship of perivascular adipose tissue and atherosclerosis in the aorta and carotid arteries, determined by magnetic resonance imaging

BACKGROUND AND AIMS

Imaging studies have relied on the 'overall' volumetric quantification of perivascular adipose tissue. We sought to assess the relationship of circumferential distribution between perivascular adipose tissue and adjacent wall thickness of carotid and aortic arteries using dedicated magnetic resonance imaging sequences.

METHODS

Vessel wall and perivascular adipose tissue were acquired using magnetic resonance imaging (1.5 T). Co-registered images were segmented separately, and measurements of both perivascular adipose tissue and vessel wall were obtained along radii of the vessel spaced at angles of 5° each.

RESULTS

In total, 29 patients were recruited. Perivascular adipose tissue thickness of the aorta was 3.34 ± 0.79 mm with specific pattern of 'double peaks' distribution, while carotid perivascular adipose tissue had no identifiable pattern with thickness of 0.8 ± 0.91 mm. Although statistically significant, the correlation between perivascular adipose tissue thickness and wall thickness in carotid arteries with normal (r = 0.040, p = 0.001) or with abnormal wall thickness (r = -0.039, p = 0.015) was merely nominal. Similarly, perivascular adipose tissue of the aorta had very weak correlation with normal aortic wall thickness (r = 0.010, p = 0.008) but not with the abnormal ones (r = -0.05, p = 0.29).

CONCLUSION

Dissociation between the spatial distribution of perivascular adipose tissue and arterial wall thickening in the aorta and carotid arteries does not support that perivascular adipose tissue has a causal role in promoting atherosclerotic plaque via a paracrine route. Yet, perivascular adipose tissue functional properties were not examined in this study.

Endothelium-derived extracellular vesicles promote splenic monocyte mobilization in myocardial infarction

Transcriptionally activated monocytes are recruited to the heart after acute myocardial infarction (AMI). After AMI in mice and humans, the number of extracellular vesicles (EVs) increased acutely. In humans, EV number correlated closely with the extent of myocardial injury. We hypothesized that EVs mediate splenic monocyte mobilization and program transcription following AMI. Some plasma EVs bear endothelial cell (EC) integrins, and both proinflammatory stimulation of ECs and AMI significantly increased VCAM-1-positive EV release. Injected EC-EVs localized to the spleen and interacted with, and mobilized, splenic monocytes in otherwise naive, healthy animals. Analysis of human plasma EV-associated miRNA showed 12 markedly enriched miRNAs after AMI; functional enrichment analyses identified 1,869 putative mRNA targets, which regulate relevant cellular functions (e.g., proliferation and cell movement). Furthermore, gene ontology termed positive chemotaxis as the most enriched pathway for the miRNA-mRNA targets. Among the identified EV miRNAs, EC-associated miRNA-126-3p and -5p were highly regulated after AMI. miRNA-126-3p and -5p regulate cell adhesion- and chemotaxis-associated genes, including the negative regulator of cell motility, plexin-B2. EC-EV exposure significantly downregulated plexin-B2 mRNA in monocytes and upregulated motility integrin ITGB2. These findings identify EVs as a possible novel signaling pathway by linking ischemic myocardium with monocyte mobilization and transcriptional activation following AMI.

Association between antidepressant prescribing and suicide rates in OECD countries: an ecological study

INTRODUCTION

We have conducted an ecological study to assess the association between antidepressant prescribing and suicide rates using the Organisation for Economic Co-operation and Development (OECD) health data, making this the largest ecological study in recent times.

METHOD

Data were derived for the years 1995-2008 from the OECD health data set. The residuals for all variables were adjusted for country and year within each country. These were then analysed to identify predictors of suicide rate. Pearson's rank correlation coefficient and linear regression model were employed to assess associations and identify significant predictors of suicide rate.

RESULTS

Suicide rate has significant positive correlations with antidepressant rates (p=0.031) and unemployment (p=0.028). It also has a significant negative correlation with inpatient psychiatric beds (p=0.039). The actual coefficients are less than ±0.16, indicating weak relationships. After adjusting for other variables, the only variable that is a statistically significant predictor of suicide rate is antidepressant prescribing (p=0.005, r²=0.09).

DISCUSSION

Our analysis using this large data set suggests a statistically significant, albeit weak positive, association between antidepressant prescribing and suicide rates.

Results of a feasibility study for a psycho-educational intervention in head and neck cancer

BACKGROUND

With survival rates for people with head and neck (H&N) cancers static during the past 30 years and the enormous burden of psychosocial impacts they suffer well documented, the testing of psychosocial interventions in this group is a priority.

OBJECTIVE

To test the feasibility of providing a psycho-educational intervention for people with H&N cancer.

METHODOLOGY

A prospective non-randomised design was used. Subjects were patients with H&N cancer. They were offered the Nucare coping strategies program in one of three formats: small group and one-to-one formats with therapists; and a home format, with material for home use, without a therapist. Outcomes measures (quality of life (QOL) and anxiety and depression) were collected at baseline and following the intervention. Analyses were performed using non-parametric statistics.

RESULTS

Of 128 people invited to participate, 66 agreed, 59 completed the intervention and 50 had outcomes data. Following the intervention, there were significant improvements in physical and social functioning and global QOL, and reduced fatigue, sleep disturbance and depressive symptoms.

CONCLUSIONS

These data suggest that the intervention is desired by the target group, feasible to deliver after cancer therapy and may have some beneficial effects, although an appropriately designed study is required to confirm this.

Teaching head and neck cancer patients coping strategies: results of a feasibility study

To test the feasibility of providing a psycho-educational intervention for people with head and neck (H&N) cancer. A prospective non-randomized design was used. Subjects were patients with H&N cancer. They were offered the Nucare coping strategies program in one of three formats: small group and one-to-one formats with therapists; and a home format, with material for home use, without a therapist. Outcomes measures (quality of life (QOL) and anxiety and depression) were collected at baseline and following the intervention. Analyses were performed using non-parametric statistics. Of 128 people invited to participate, 66 agreed, 59 completed the intervention and 50 had outcomes data. Following the intervention, there were significant improvements in physical and social functioning and global QOL, and reduced fatigue, sleep disturbance and depressive symptoms. These data suggest that the intervention may have some beneficial effects, although an appropriately designed study is required to confirm this.

Lessons learned: Outcomes and methodology of a coping skills intervention trial comparing individual and group formats for patients with cancer

OBJECTIVE

Nucare, a short-term psychoeducational coping skills training intervention was evaluated in a randomized controlled clinical trial (RCT) of 225 newly diagnosed breast and colon cancer patients.

METHOD

Measures of psychosocial distress, well being and optimism were evaluated every four months during a one-year period. Patients were randomized to one of four arms: Nucare presented in an individual basis; Nucare presented in a group format; a non-directive supportive group; and a no-intervention control. The interventions were provided in five sessions of ninety minutes each.

RESULTS

Patients with breast cancer who received Nucare presented in an individual format showed more significant improvements in well-being over time compared to those in the control and group arms.

CONCLUSIONS

We were unable to develop functioning groups within the RCT. Partial explanations for the latter finding include the structural limitations of the RCT: the groups were small, difficult to schedule and patients indicated that they would have preferred to choose whether or not to participate in a group. The positive changes in women with breast cancer who received Nucare persisted at 12 months.

Resource use in women completing treatment for breast cancer

OBJECTIVE

To explore resources used by women completing treatment for breast cancer, how they learned about them, and the psychological factors that predicted their use.

DESIGN

A questionnaire on resource use was administered as part of a randomized clinical trial which assessed subjects' psychosocial characteristics and tested the outcomes of a psychosocial intervention.

SETTING

Women completing treatment for breast cancer were recruited from the oncology departments of three university-teaching hospitals in Montreal. A questionnaire gathered data on the resources used by the subjects, how they learned about them, and the role of the health care team in their decision-making. Emotional distress, dimensions of coping effort, a sense of control and optimism were also measured.

RESULTS

Five categories of resources were explored; professional services, informal support networks, informational resources, support organizations and complementary therapies. Most women found out about the last two resources by themselves. Women who used cancer support organizations or complementary therapies scored high on the use of problem-solving coping and low on the use of escape/avoidance coping. In addition they were moderately optimistic, had a slightly lower sense of personal control and were somewhat more distressed than the non-users. The use of support organizations and complementary therapies appears to represent a thoughtful approach to dealing with the distress of cancer. The opinion of the oncologist regarding resource use was valued by nearly half of the sample.

Nurses' motivation and its relationship to the characteristics of nursing care delivery systems: a test of the job characteristics model

The purpose of the study was to describe the relationship among motivation, job satisfaction and the characteristics of nursing care delivery systems using the Job Characteristics Model of Work Motivation (Hackman & Oldham, 1980), and to test a framework of nursing care delivery system attributes that have been found to contribute to job satisfaction and good patient care outcomes. The present era of cost containment pressures means that nurse administrators need to ensure that nurses have a work environment with the characteristics of work known to be linked to job satisfaction, motivation and good outcomes. The model was tested with nurses working in medical-surgical areas of four Montreal teaching hospitals. Findings included the applicability of the Job Characteristics Model to the work of nursing and that the addition of four attributes of nursing care delivery systems, namely support for autonomy, communication, adequate time for patient care and the degree of environmental uncertainty contributed to job satisfaction and motivation.

A randomized trial of a program of early postpartum discharge with nurse visitation

OBJECTIVE

Our purpose was to compare an early postpartum discharge program versus standard postpartum care.

STUDY DESIGN

A randomized controlled trial in a 637-bed university hospital included 175 healthy women recruited at 32 to 38 weeks gestation from physicians' offices and sonograms. Experimental intervention consisted of discharge 6 to 36 hours post partum with nursing care available by telephone or at home at 34 to 38 weeks' gestation and at < or = 48 hours and at 3, 5, and 10 days post partum. The control included a postpartum stay of 48 to 72 hours and standard follow-up.

RESULTS

At 1 month no significant differences were seen in perceived maternal competence (Experimental-Control = 4.3 points [95% confidence interval-7.7 to 16.3]), infant weight gain (1.2 gm/ day [-2.8 to 5.2]); identification of significant neonatal hyperbilirubinemia (rate ratio 0.50 [0.10 to 2.51]), infant utilization of health services (rate ratio 0.88 [0.45 to 1.73]), or predominant breast-feeding (adjusted odds ratio 1.25 [0.88 to 1.75]). Program participants did have significantly less frequent infant bilirubin testing (rate ratio 0.39 [0.17 to 0.94]). The program also enhanced perceived maternal competence in recent immigrants (26.9 points [2.7 to 51.5]).

CONCLUSIONS

Early postpartum discharge coupled with prenatal, postnatal, and home contacts leads to no apparent disadvantage and may yield benefits for some mothers and infants.

Restructuring to create a climate for clinical excellence for nursing

A fundamental responsibility and urgent requirement of health care leaders is to create and develop organizational structures and environments that support nurses and nurses' work--whose ultimate goal is to support the analytical, interpersonal and technical skills that combine with knowledge to produce wise and thoughtful caring. The ways in which structure can facilitate and enhance care delivery often are not clearly understood. This article describes a strategic reorientation and reorganization of the Department of Nursing of the Sir Mortimer B. Davis Jewish General Hospital in Montréal, designed to meet the needs of patients, nurses and the hospital more effectively.

Coping with cancer during the first year after diagnosis. Assessment and intervention

The emotional coping of 205 patients newly diagnosed with cancer was evaluated every 4 months during a 1-year period. Patients received a psychosocial intervention either immediately (early intervention, EI), or after a 4-month delay (later intervention, LI). No significant differences were found between the two groups, except at 8 months, when the LI group was significantly less depressed, anxious, and worried, and felt more in control than the EI group. The LI group continued to have less worry related to illness at 12 months. Patients with high ego strength had low levels of distress at baseline and may not have needed the intervention. The emotional coping of patients with breast cancer improved during the year regardless of the intervention timing. Patients with other diagnoses appeared to benefit most from the IL. It was concluded that patients with low ego strength and diagnoses other than breast cancer might be at higher risk for psychosocial complications and could benefit from the intervention.

A survey examining nurses' knowledge of pain control

Three hundred and eighteen (318) nursing staff members at an acute care teaching hospital in Montreal, Canada, were surveyed to identify their knowledge of pain assessment and management. Two pain instruments were combined and adapted for use. The final instrument consisted primarily of true/false responses and took about 10 min to complete. The mean score was 63.9%. Overall results indicated that nurses lacked knowledge and understanding of opioid addiction, equivalent dosing, properties of opioids, and differences in acute and chronic pain. No statistically significant differences were found in the scores by level of educational preparation or by years of experience. Presentation of the results unit by unit demonstrated that the instrument is suitable as an educational tool as well as an effective strategy to introduce nursing staff to nursing research.

Specification of male development in Caenorhabditis elegans: the fem genes

Mutation of the gene fem-2 causes feminization of both sexes: hermaphrodites make no sperm, and males produce oocytes in an intersexual somatic gonad. A double mutant harboring ts alleles of both fem-1 (formerly named isx-1; G. A. Nelson, K. K. Lew, and S. Ward, 1978, Dev. Biol. 66, 386-409) and fem-2 causes transformation of XO animals (normally male) into spermless hermaphrodites at restrictive temperature. The phenotypes, temperature-sensitive periods, and maternal effects observed in mutants of each fem gene are found to be similar. It is suggested that the fem genes are centrally involved in specification of male development in Caenorhabditis elegans--both in the germ line of hermaphrodites and in somatic and germ line tissues of males.

Factors affecting the nurse as a teacher and practicer of breast self-examination

The purpose of this study was to compare the knowledge, attitudes, confidence and practice of breast self-examination of a group of hospital-employed nurses and non-nurses, in an attempt to understand the factors which influence why nurses do not teach or practice breast self-examination more significantly. A 41-item questionnaire administered to 380 female hospital employees compared data on demographics, risk factors, practice, knowledge, perceived susceptibility and reasons for and against practice. The findings show significant differences in knowledge levels and confidence between the nurse and non-nurse group. The differences between the two groups in frequency of practice, however, are extremely small. The significance of these findings to nursing education is discussed.

Characterization of a bacterium of the genus Azospirillum from cellulolytic nitrogen-fixing mixed cultures

A bacterium with the taxonomic characteristics of the genus Azospirillum was isolated from celluloytic N2-fixing mixed cultures. Its characteristics fit the descriptions of both Azopirillum lipoferum (Beijerinck) comb. nov. and Azospirillum brasilense sp. nov. It may be a variant strain of A. lipoferum. In mixed cultures with cellulolytic organisms, the bacterium grew and fixed N2 with cellelose as a sole source of energy and carbon. The mixed cultures used cellulose from leaves of wheat (Triticum aestivum L.), corn (Zea mays L.), and big bluestem grass (Andropogon gerardii Vitm). Microaerophilic N2-fixing bacteria of the genus Azospirillum, such as the bacterium we isolated, may be important contributors of fixed N2 in soil with partial anaerobiosis and cellulose decomposition.

Reversible alteration in the neuromuscular junctions of Drosophila melanogaster bearing a temperature-sensitive mutation, shibire

In this study we report a relationship between the ultrastruct of the neuromuscular junctions of tibial muscles and the temperature-induced paralysis in shibire flies. There is a decrease in the number of synaptic vesicles of neuromuscular junctions in flies which are held at or above 29 degrees. Shortly after return to 22 degrees C, the synaptic vesicles are again present in large numbers. Prior treatment with tetrodotoxin or barbiturate protects the junctions from the temperature change in morphology.