Mobile genes in the human microbiome are structured from global to individual scales.

Recent work has underscored the importance of the microbiome in human health, and has largely attributed differences in phenotype to differences in the species present among individuals. However, mobile genes can confer profoundly different phenotypes on different strains of the same species. Little is known about the function and distribution of mobile genes in the human microbiome, and in particular whether the gene pool is globally homogenous or constrained by human population structure. Here, we investigate this question by comparing the mobile genes found in the microbiomes of 81 metropolitan North Americans with those of 172 agrarian Fiji islanders using a combination of single-cell genomics and metagenomics. We find large differences in mobile gene content between the Fijian and North American microbiomes, with functional variation that mirrors known dietary differences such as the excess of plant-based starch degradation genes found in Fijian individuals. Notably, we also observed differences between the mobile gene pools of neighbouring Fijian villages, even though microbiome composition across villages is similar. Finally, we observe high rates of recombination leading to individual-specific mobile elements, suggesting that the abundance of some genes may reflect environmental selection rather than dispersal limitation. Together, these data support the hypothesis that human activities and behaviours provide selective pressures that shape mobile gene pools, and that acquisition of mobile genes is important for colonizing specific human populations.

Improving the diagnosis of LV non-compaction with cardiac magnetic resonance imaging.

BACKGROUND: Current diagnostic criteria for left ventricular non-compaction (LVNC) poorly correlate with clinical outcomes. We aimed to develop a cardiac magnetic resonance (CMR) based semi-automated technique for quantification of non-compacted (NC) and compacted (C) masses and to ascertain their relationships to global and regional LV function. METHODS: We analysed CMR data from 30 adults with isolated LVNC and 20 controls. NC and C masses were measured using relative signal intensities of myocardium and blood pool. Global and regional LVNC masses was calculated and correlated with both global and regional LV systolic function as well as occurrence of arrhythmia. RESULTS: LVNC patients had significantly higher end-systolic (ES) and end-diastolic (ED) NC:C ratios compared to controls (ES 0.21 [SD 0.09] vs. 0.12 [SD 0.02], p<0.001; ED 0.39 [SD 0.08] vs. 0.26 [SD 0.05], p<0.001). NC:C ratios correlated inversely with global ejection fraction, with a stronger correlation in ES vs. ED (r=-0.58, p<0.001 vs. r=-0.30, p=0.03). ES basal, mid and apical NC:C ratios also showed a significant inverse correlation with global LV ejection fraction (ES basal r=-0.29, p=0.04; mid-ventricular r=-0.50, p<0.001 and apical r=-0.71, p<0.001). Upon ROC testing, an ES NC:C ratio of 0.16 had a sensitivity of 70% and a specificity of 95% for detection of significant LVNC. Patients with sustained ventricular tachycardia had a significantly higher ES NC:C ratio (0.31 [SD 0.18] vs. 0.20 [SD 0.06], p=0.02). CONCLUSIONS: The NC:C ratio derived from relative signal intensities of myocardium and blood pool improves the ability to detect clinically relevant NC compared to previous CMR techniques.

Gene decay in archaea.

The gene-dense chromosomes of archaea and bacteria were long thought to be devoid of pseudogenes, but with the massive increase in available genome sequences, whole genome comparisons between closely related species have identified mutations that have rendered numerous genes inactive. Comparative analyses of sequenced archaeal genomes revealed numerous pseudogenes, which can constitute up to 8.6% of the annotated coding sequences in some genomes. The largest proportion of pseudogenes is created by gene truncations, followed by frameshift mutations. Within archaeal genomes, large numbers of pseudogenes contain more than one inactivating mutation, suggesting that pseudogenes are deleted from the genome more slowly in archaea than in bacteria. Although archaea seem to retain pseudogenes longer than do bacteria, most archaeal genomes have unique repertoires of pseudogenes.

Evaluating the graduates of the Dalhousie University School of Nursing baccalaureate programme: a quantitative/qualitative responsive model.

The purpose of this study was to determine if the Dalhousie University School of Nursing's curriculum enabled its graduates to meet the terminal objectives of the programme and to determine if these objectives were consistent with the requirements of their employers. An explorative, descriptive design using qualitative and quantitative data were employed through a mailed survey and employer focus groups. Stufflebeam's model served as the conceptual framework to guide this product evaluation. The setting for this study was a baccalaureate school of nursing and eight employing agencies in eastern Canada. A total of 190 graduates were sampled comprising basic and post-RN graduates from the class of 1989 to 1991 inclusive. The response rate was 40.5% (n = 77). Analysis of data included frequency and percentage calculations and thematic descriptions of employer and graduate responses. Findings of this study indicated that the graduates and their respective employers rated the nursing programme to be very satisfactory. Implications for curriculum accountability are discussed.

Evaluation of different medium supplements for in vitro cultivation of Brugia malayi third-stage larvae.

Growth and development of Brugia malayi (Nematoda: Filarioidea) third-stage larvae (L3) were compared in 5 medium supplements. The basic culture medium (NI) consisted of a 1:1 (v/v) mixture of NCTC-135 and Iscove's modified Dulbecco's medium, an antibiotic/antimycotic mixture, and 1 of the following 5 supplements: 25 mg/ml bovine albumin fraction-V (BAF), 10% fetal bovine serum (FBS), 10% commercially obtained human serum (CHS), 10-15% pooled human serum from hospital patients (PHS), and 10-15% human serum from a single individual (SHS). Cultures were maintained at 37 C in an atmosphere of 5% CO2 in air. NI-BAF and NI-CHS did not support molting of L3 to fourth-stage larvae (L4), whereas NI-FBS, NI-PHS, and NI-SHS did support molting of L3 to L4 but only the larvae in NI-SHS attempted the fourth molt. Growth and development of in vitro larvae in NI-PHS and NI-SHS were comparable to that observed in jirds for the first 28 days, after which the in vitro larvae lagged behind in vivo larvae. Optimal growth and development may be dependent on certain as yet unidentified components of specific human serum.

Preparing health professionals for a collaborative health promotion role.

Practitioners and educators must consider whether or not the curriculum offered in a university setting by our health professional schools prepares the potential practitioner for work in the multisectorial, interdisciplinary milieu that has been recommended by The Alma Ata Declaration, the Epp Health Promotion document and the Ottawa Charter. I describe a final-year course in Community Health Nursing that is being offered by Dalhousie University School of Nursing. The course is open to generic and post-registration nurses. The course, based on adult learning principles, used a collaborative community development approach. The curriculum was designed to give baccalaureate student nurses the experience of participating in collaborative health promotion directed towards the strengthening of a community. Student, faculty, preceptor and service-based coordinators' evaluation of the two-year implementation of the course is described in the paper.

Primary health care through a community based smoking-cessation program.

The International Conference on Primary Health Care, meeting in Alma-Ata, in the Soviet Union, September 12, 1978, expressed the need for urgent action by all governments, all health and development workers and the world community, to protect and promote the health of all people of the world. The world was caught by the phrase which emerged from this conference, "Health For All by the Year 2000" and many have examined the articles of the Alma-Ata declaration and tried to implement them in their corner of the world. This paper describes a community-based smoking-cessation program which was implemented in the province of Nova Scotia, Canada, during the years 1980-1984. Primary to this project was the belief that people have the right and the duty to participate individually and collectively in planning and implementing their health care. This paper describes one community's effort in putting this belief into practice.

Planning and evaluation of cross-cultural health education activities.

This paper was written to assist health professionals who are or who are planning to undertake health education activities with people of a different culture. The focus is on the educative function of health promotion. A short summary of relevant learning theory is presented. Some obstacles (pitfalls) encountered in cross-cultural transfer of information, knowledge and skills are presented and the effects of this learning process on the learner and teacher are explored. Examples of possible conflict situations drawn from the author's experiences and research are presented. Variables which influence planning and implementation of health education in cross-cultural settings are examined. A cyclical model which identifies critical questions to be asked and decisions to be made in a four-phased process of assessment, planning, implementation and evaluation is described for the use of health educators in transcultural settings. The need for systematic cultural assessment prior to planning is stressed to ensure relevancy, acceptance and positive outcome of programmes. Cooperative efforts of health educators with existing systems and traditional teachers and involvement of clients during all phases of the decision making process are suggested.

A proposed framework for evaluation of support courses in a nursing curriculum.

Evaluation of nursing educational programmes has received increased attention since the early 1970s. Many evaluation models have been proposed; they are intended for evaluation of the total educational programme, but provide little evidence on the relevancy of the support courses to nursing practice. This paper describes one nursing school's experience in evaluation of a support course. The nature and sources of problems and difficulties encountered during the evaluation process are also discussed. The authors propose a framework for evaluation of support courses in a nursing curriculum. This framework is an application of the Glaser, Stufflebeam and Stake models of programme evaluation. It is designed to assist nurse educators to strive for sound curriculum decisions.