Nontarget arthropod abundance in areawide-managed corn habitats treated with semiochemical-based bait insecticide for corn rootworm (Coleoptera: Chrysomelidae) control.

Impacts of semiochemical-based insecticidal bait applications on beneficial arthropod groups common to field corn, Zea mays L., habitats were assessed in areawide-managed field sites in South Dakota and Iowa during 1997 and 1998. Slam, a commercial bait formulation comprised of 87% cucurbitacin and 13% carbaryl insecticide, was used for management of adult rootworm, Diabrotica spp., and controls consisted of cornfield habitats without bait applications. Effects on beneficial organisms were variable, and negative impacts were infrequent. Coccinellidae, Staphylinidae, and Anthocoridae were usually more abundant in bait-treated plots than in controls that received at-plant soil insecticides, especially by 4 wk postapplication. Carabid beetle activity also had increased in bait-treated corn by proportionally greater rates than in control plots at 4 wk postapplication in two of the four site by year combinations in this study. Impacts of semiochemical-based adulticide applications on Formicidae were not consistently negative or positive. The relative lack of consistent negative impacts on nontarget arthropods suggests that other biotic and abiotic factors leading to natural population fluxes may have more influence on these groups of beneficial organisms than applications of semiochemical-based bait containing carbaryl. Overall, it seems that areawide applications of these baits for managing rootworm populations in corn are not likely to impose deleterious effects on the nontarget faunal groups we surveyed, especially in comparison with the at-plant applications of soil insecticides used as experimental controls in this study.

What you ask is what you get: learning from interviewing in qualitative research.

This paper outlines some important issues discovered about undertaking qualitative interviews. A description of a study that involved interviewing the authors' students is followed by discussion of aspects of the interviewing process that became apparent during analysis of those interviews. Problems that were encountered with retrospective interviews, power differentials, question sequencing, some interview techniques, and a prior knowledge of the students are illuminated to assist other qualitative interviewers to be aware of these potential areas of difficulty.

Moving from technical to critical reflection in journalling: an investigation of students' ability to incorporate three levels of reflective writing.

This paper outlines a research project aimed at changing the levels of reflection of preregistration nursing students in a tertiary institution. Whilst reflection is widely espoused now in nursing, few studies have been found that identify whether the level of reflective writing can be identified or developed by students. Anecdotal and research evidence (Powell 1989; van Manen 1977) however indicates that most student reflective writing occurs at the technical level. A descriptive exploratory study using both qualitative and quantitative techniques was undertaken to apply van Manen's (1977) levels in a structured way in an attempt to facilitate the student's understanding and use of the levels in their reflective writing. The findings of the study indicate that student self evaluation and identification of the levels in their own writing can lead to change in the levels of critical reflective writing achieved by undergraduate students.

An exploration of the preceptor role: preceptors' perceptions of benefits, rewards, supports and commitment to the preceptor role.

This Australian study, a replication of Canadian research by Dibert & Goldenberg, was undertaken to explore the relationship between preceptors' perceptions of benefits, rewards and support, and their commitment to the preceptor role. A convenience sample of 134 nurse preceptors involved in an undergraduate nursing course were invited to complete a four-part questionnaire consisting of the Preceptor's Perception of Benefits and Rewards Scale, the Preceptor's Perception of Support Scale, the Commitment to the Preceptor Role Scale, and demographic details. The results, in the main, parallel those of the original research, with differences reflecting the distinct nature and the more recent use of preceptorship in Australia. The results indicate a clear commitment to the preceptor role and a perception that both material and non-material benefits are derived from acting in the role. Additionally, support from the institution and coworkers was considered vital for participation in the role. This not only has implications for nursing educators, administrators and potential preceptors, but also for those being preceptored.

Reflective writing: a strategy to foster critical inquiry in undergraduate nursing students.

Whilst nursing has recognised the importance of reflective practitioners, few strategies designed to achieve this outcome are currently apparent in nursing education literature. Writing, forwarded as one way to enhance the development of critical thinking and reflection in undergraduate nursing students, is the focus of this article. The article describes a project undertaken to explore the ways writing could be incorporated into an undergraduate curriculum as a strategy to enhance and extend personal and professional meaning-making. It examines a number of strategies utilised in the project and offers some insightful understandings developed by the team.

'It comes together at the end': the impact of a one-year subject in Nursing Inquiry on philosophies of nursing.

This paper reframes an interpretive study as critical inquiry as the researchers interrogate their roles and authority in the 'reading' of what is valued as reflective. Working from data collected in written philosophies and interviews within the context of a one-year subject aimed at developing reflective practice and an appreciation of ways of knowing, this paper examines the change in philosophies of nursing perceived by three university-based educators and their students. The study reveals a growing appreciation of the complexity of nursing but a limited consideration of the dialectic of critical theorising and everyday engagement necessary to critical reflection and reconstruction of action. More importantly, the process of research collaboration raises questions of the soul-searching necessary for university educators to act against the institutionalised political context that determines what is seen to be of value in student learning.

A survey to determine the prevalence of leprosy in a community in east Trinidad.

A house-to-house survey was conducted in a community in East Trinidad, where a clustering of cases had been observed. There were 1355 residents, of whom 73.5% had a complete visual skin examination. No new cases of leprosy were found but a variety of skin disorders were diagnosed. The most common disorder was pityriasis versicolor, which is one of the differential diagnoses of hypopigmented skin lesions. This has serious implications for the delayed diagnosis of leprosy. In all, 5 of the 9 old cases residing in the survey area suffered from paucibacillary disease, and had a history of contact with a lepromatous case. They were not listed initially as contacts of this index case. Contact lists should therefore include nonfamilial persons having frequent contact with an index case. The definition of 'frequent' should be determined by each programme. It may also be necessary to review the duration of surveillance of contacts. The survey was estimated to have cost about US $2,500 and was not considered to be cost-effective.

Attitudes and practices of pesticide users in Saint Lucia, West Indies.

This article reports the results of a Saint Lucia survey, part of a larger program, that was the first to document the prevalence of suboptimal safety practices among vector control and farm workers using pesticides in the English-speaking Caribbean. Among other things, the survey found that many of 130 pesticide users surveyed were unaware that the skin and eyes were important potential routes of absorption. Over a quarter said they had felt ill at some point as a result of pesticide use. About half the respondents said they had received more than "introductory" training in safe pesticide use, and most said they always found labels or directions affixed to pesticide containers. However, about half said they never or only sometimes understood the labels, and many of those who said they understood did not always follow the instructions. About a quarter of the smokers said they smoked while using pesticides; about a sixth of the survey subjects said they ate food while using pesticides; and over 60% said they never wore protective clothing.

Attitudes and practices of pesticide users in Saint Lucia, West Indies

This article reports the results of a Saint Lucia survey, part of a larger program, that was the first to document the prevalence of suboptimal safety practices among vector control and farm workers using pesticides in the English-speaking Caribbean. Among other things, the survey found that many of 130 pesticide users surveyed were unaware that the skin and eyes were important potential routes of absorption. Over a quarter said had felt ill at some point as a result of pesticide use. About half the respondents said they had received more than "introductory" training in safe pesticide use, and most said they always found labels or directions affixed to pesticide containers. However, about half said they never or only sometimes understood the labels, and many of those who said they understood did not always follow the instructions. About a quarter of the smokers said they smoked while using pesticides; about a sixth of the survey subjects said they ate food while using pesticides; and over 60 percent said they never wore protective clothing

Attitudes and practices of pesticide users in Saint Lucia, West Indies

This article reports the results of a Saint Lucia survey, part of a larger program, that was the first to document the prevalence of suboptimal safety practices among vector control and farm workers using pesticides in the English-speaking Caribbean. Among other things, the survey found that many of 130 pesticide users surveyed were unaware that the skin and eyes were important potential routes of absorption. Over a quarter said had felt ill at some point as a result of pesticide use. About half the respondents said they had received more than "introductory" training in safe pesticide use, and most said they always found labels or directions affixed to pesticide containers. However, about half said they never or only sometimes understood the labels, and many of those who said they understood did not always follow the instructions. About a quarter of the smokers said they smoked while using pesticides; about a sixth of the survey subjects said they ate food while using pesticides; and over 60 percent said they never wore protective clothing

Epidemiological indicators and the epidemiology of measles in the English-speaking Caribbean and Suriname.

The main purpose of this article is to discuss the definitions and limitations of the indicators used to study the epidemiology of measles in the English-speaking Caribbean and Suriname. In addition, the epidemiology of measles over the past ten years is briefly reviewed, with a focus on recent epidemics. The predicted epidemiological picture of measles over the next few years is also discussed and, finally, the difference between elimination and eradication of measles is explained.

Epidemiological indicators and epidemiology of measles in the English-speaking Caribbean and Suriname

The main purpose of this article is to discuss the definitions and limitations of the indicators used to study the epidemiology of measles in the English-speaking Caribbean and Suriname. In addition, the epidemiology of measles over the past ten years is briefly reviewed, with a focus on recent epidemics. The predicted epidemilogical picture of measles over the next few years is also discussed and, finally, the difference between elimination and eradiction of measles is explained.

Cholesteryl ester transfer protein in human brain.

The evidence that apolipoproteins are found in the cerebrospinal fluid and low-density lipoprotein receptor is found in the brain suggests that the brain may have an active lipid transport system. In plasma, cholesteryl ester transfer protein mediates the exchange and net transfer of cholesteryl ester and triglycerides among lipoproteins. Cholesteryl ester transfer activity was measured in the cerebrospinal fluid and plasma of ten neurologically normal subjects. Cholesteryl ester transfer activity was readily detectable in cerebrospinal fluid (7.4 +/- 13% cholesteryl ester was transferred per 20 microliters), and this activity was completely abolished with specific antibody against the plasma cholesteryl ester transfer protein. The concentration of cholesteryl ester transfer activity in the cerebrospinal fluid was about 12% of that found in plasma, whereas the concentration of albumin in cerebrospinal fluid was only about 0.6% of that in plasma, suggesting direct synthesis of cholesteryl ester transfer protein within the brain. Cholesteryl ester transfer activity was found in conditioned medium from human neuroblastoma and neuroglioma cells and sheep choroid plexus. The data suggest that cholesteryl ester transfer protein is synthesized and secreted in the brain. This protein could play an important role in the transport and redistribution of lipids within the central nervous system.

Regulation of LTP-I secretion from human monocyte-derived macrophages by differentiation and cholesterol accumulation in vitro.

Human macrophages in vitro synthesize and secrete the cholesteryl ester (CE) transfer protein, LTP-I. The effect of differentiation of monocyte-to-macrophage on the synthesis and secretion of LTP-I cholesteryl ester transfer activity was investigated. One marker of macrophage differentiation is expression of the 'scavenger' receptor, which mediates macrophage uptake and degradation of acetylated low-density lipoprotein. Monocytes secreted very little detectable CE transfer activity in the first 24 h following cell isolation. Both CE transfer activity and scavenger receptor activity increased with time in culture. Thus, although circulating monocytes probably do not secrete CE transfer activity, tissue macrophages such as hepatic Kupffer cells may contribute to plasma CE transfer activity. Resident macrophages of the arterial wall are derived from circulating monocytes which enter the vessel wall where they differentiate into macrophages. Such macrophages are the principal source of lipid-laden foam cells of the atherosclerotic plaque. Cholesterol accumulation results when uptake of lipoprotein cholesterol overwhelms the capacity of macrophages to excrete cholesterol. Since LTP-I is postulated to function in reverse cholesterol transport, the effect on LTP-I secretion of loading macrophages with cholesterol was determined after exposure of macrophages to acetylated-LDL or free cholesterol (FC). Cholesterol loading by both these maneuvers resulted in dose-dependent increases in macrophage secretion of CE transfer activity, and there was a significant positive correlation between CE transfer activity secreted and accumulation of CE. Thus, LTP-I may function at the cellular level in maintenance of lipid homeostasis: macrophage LTP-I secretion may be a protective mechanism in response to excess cholesterol accumulation in resident macrophages of the arterial wall.

Inhibition of lipid transfer by a unique high density lipoprotein subclass containing an inhibitor protein.

We have isolated from human plasma a unique subclass of the high density lipoproteins (HDL) which contains a potent lipid transfer inhibitor protein (LTIP) that inhibited cholesteryl ester, triglyceride, and phospholipid transfer mediated by the lipid transfer protein, LTP-I, and phospholipid transfer mediated by the phospholipid transfer protein, LTP-II. This HDL subclass not only inhibited cholesteryl ester transfer from HDL to LDL or VLDL, but also inhibited cholesteryl ester transfer from HDL to HDL. The inhibitor protein was isolated by sequential chromatography of human whole plasma on dextran sulfate-cellulose, phenyl-Sepharose, and chromatofocusing chromatography. Isolated LTIP had the following characteristics: an apparent molecular weight of 29,000 +/- 1,000, (n = 10) by sodium dodecyl sulfate gel electrophoresis, and an isoelectric point of 4.6 as determined by chromatofocusing. LTIP remained functional following delipidation with organic solvents. Antibody to LTIP was produced, and an immunoaffinity column of the anti-LTIP was prepared. Passage of human, rat, or pig whole plasma over the anti-LTIP column enhanced cholesteryl ester transfer activity in human (17%), pig (200%), and rat plasma (125%). The HDL subclass containing LTIP was isolated from whole human HDL (d 1.063-1.21 g/ml) by immunoaffinity chromatography. The isolated LTIP-HDL complex was shown to: i) contain about 60% protein and 40% lipid, ii) have alpha and pre-beta electrophoretic mobility, iii) have particle size distribution somewhat smaller than whole HDL, about 100,000 daltons, as determined by gradient gel electrophoresis, and iv) contain only a small amount of apoA-I (less than 5%) and a trace amount of apoA-II. Assay of ultracentrifugally obtained lipoprotein fractions revealed that approximately 85% of the total functional LTIP activity was in the d 1.063-1.21 g/ml HDL fraction. Furthermore, immunoblot analysis of whole plasma by nondenaturing gradient gel electrophoresis revealed that LTIP was found predominantly in particles in the size range of HDL. This unique HDL subclass may play an important role in the regulation of plasma lipid transfer and metabolism.

Regulation of plasma lipid transfer by the high-density lipoproteins.

Mechanisms that regulate the activity of the plasma cholesteryl ester transfer protein (lipid protein transfer-I) are poorly understood. We have examined the role of endogenous regulators of the lipid transfer process, in particular the plasma high-density lipoproteins (HDLs), in both humans and two species previously reported to be devoid of cholesteryl ester transfer activity, the rat and the pig. Chromatography of d greater than 1.21 g/ml plasma on phenyl-Sepharose either enhanced (human) lipid transfer activity or unmasked (rat and pig) a nearly completely suppressed lipid transfer activity. The HDLs (either native or delipidated) were shown to be a rich source of a plasma lipid transfer inhibitor protein. Partial purification of the HDL-derived lipid transfer inhibitor protein was achieved by sequential chromatography on phenyl- and DEAE-Sepharose. Additional analysis of plasma from patients with very low (Tangier disease), normal, or very high levels of HDL cholesterol (hyperalphalipoproteinemia) revealed a significant inverse correlation between plasma cholesteryl ester transfer activity and the subjects HDL cholesterol level. These results suggest that circulating levels of the plasma high density lipoproteins may be an important determinant of plasma cholesteryl ester transfer activity, through the function of the HDL-derived lipid transfer inhibitor protein.

Isolation and characterization of a phospholipid transfer protein (LTP-II) from human plasma.

In this report we have described the purification of a human plasma phospholipid transfer protein, designated LTP-II, which displayed the following characteristics: i) facilitated both the exchange and net mass transfer of lipoprotein phospholipids; ii) did not facilitate the transfer of lipoprotein cholesteryl esters (CE) or triglycerides (TG); iii) was not recognized by antibody to the human cholesteryl ester transfer protein (LTP-I); iv) showed no amino acid sequence homology to the cholesteryl ester transfer protein (LTP-I); v) has an apparent molecular weight (Mr) of 70,000 off Sephacryl S200, and 69,000 off sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE); vi) has an apparent isoelectric point of 5.0 by chromatofocusing; and vii) when added to an incubation mixture of VLDL, HDL3, and the human plasma cholesteryl ester transfer protein (LTP-I), enhanced the observed transfer of cholesteryl esters from HDL3 to VLDL, even though LTP-II has no intrinsic cholesteryl ester transfer activity of its own. These results show that this phospholipid transfer protein is unique from the human plasma cholesteryl ester transfer protein, and may play an important role in human lipoprotein lipid metabolism.

Distribution and localization of lecithin:cholesterol acyltransferase and cholesteryl ester transfer activity in A-I-containing lipoproteins.

Two types of A-I-containing lipoproteins are found in human high density lipoproteins (HDL): particles with A-II (Lp(A-I with A-II] and particles without A-II (Lp(A-I without A-II]. We have studied the distribution of lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer (CET) activities in these particles. Lp(A-I with A-II) and Lp(A-I without A-II) particles were isolated from ten normolipidemic subjects by anti-A-I and anti-A-II immunosorbents. Most plasma LCAT mass (70 +/- 15%), LCAT (69 +/- 16%), and CET (81 +/- 15%) activities were detected in Lp(A-I without A-II). Some LCAT (mass: 16 +/- 7%, activity: 17 +/- 8%) and CET activities (7 +/- 8%) were detected in Lp(A-I with A-II). To determine the size subspecies that contain LCAT and CET activities, isolated Lp(A-I with A-II) and Lp(A-I without A-II) particles of six subjects were further fractionated by gel filtration column chromatography. In Lp(A-I without A-II), most LCAT and CET activities were associated with different size particles, with the majority of the LCAT and CET activities located in particles with hydrated Stokes diameters of 11.6 +/- 0.4 nm and 10.0 +/- 0.6 nm, respectively. In Lp(A-I with A-II), most of the LCAT and CET activities were located in particles similar in size: 11.1 +/- 0.4 nm and 10.6 +/- 0.3 nm, respectively. Ultracentrifugation of A-I-containing lipoproteins resulted in dissociation of both LCAT and CET activities from the particles. Furthermore, essentially all CET and LCAT activities were recovered in the non-B-containing plasma obtained by anti-LDL immunoaffinity chromatography. This report, therefore, provides direct evidence for the association of LCAT and CET protein with A-I-containing lipoproteins. Our conclusions pertain to fasting normolipidemic subjects and may not be applicable to hyperlipidemic or nonfasting subjects.