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Biomedical subjects

C O Boyd

Publications and source records attributed to C O Boyd.

17 recordsLinked to original sources
PubMed1998

Primary care of the older adult with end-stage Alzheimer's disease.

End-of-life care is slowly being recognized as a dimension of primary care. Although terminal care programs have been established largely in response to the needs of cancer and AIDS patients, few clinical guidelines exist for end-of-life care in other diagnostic categories. Hospice philosophy and the palliative care literature provide the grounds for designing primary care approaches for a variety of noncancer, terminally ill patients. A growing need for hospice/palliative care exists for end-stage Alzheimer's patients. This article describes end-stage Alzheimer's disease and proposes ways a primary care provider may participate in the terminal care process. A patient education handout discussing end-stage Alzheimer's disease issues and providing family resources is presented.

Aged↗
PubMed1997

When the hospice patient is manipulative.

Oncology and hospice literature have addressed the problem of psychiatric complications, secondary to the stressors of diagnosis and treatment. This literature focuses particularly on depression and anxiety, which not only compound patients' suffering but also may interfere with optimal care. Little attention has been given, however, to the unique challenges of providing hospice care to patients with preexisting psychiatric conditions. As hospice care becomes increasingly mainstream in the health care system, we can expect to meet more patients with such conditions. In order to contribute to collegial dialogue that addresses this minority population in hospice services, a case study is presented in this article of the process of care for a hospice patient with a preexisting psychiatric condition. Interventions are suggested, using a theoretical matrix of hospice philosophy and principles of care for manipulative patients.

Adaptation, Psychological↗
PubMed1995

Striking changes in the structure and organization of rat fetal membranes precede parturition.

Premature rupture of fetal membranes can harm infant and mother. It is unclear whether structural changes predispose these membranes to breaking. We thus assessed rat visceral yolk sac placenta (VYSP) and amnion by light and by transmission electron microscopy on Days 18-21 of gestation. Light microscope sections were stained for connective tissue (extracellular matrix) components: collagen, glycoprotein, and glycosaminoglycans/proteoglycans. Some tissue was incubated with chondroitinase ABC. We observed that fetal membranes became increasingly fragile, rupturing readily on Day 21. On Days 18-20, the two epithelial layers of the capsular VYSP were separated by a well-developed, well-vascularized connective tissue layer that stained intensely for all matrix components studied; on Day 21, the connective tissue layer was thinner, moderately stained, and less vascularized. On Days 18-20, the two cellular layers of the amnion were separated by a narrow, compact connective tissue layer that stained modestly for all matrix components; on Day 21, this area was widened and stained faintly. Transmission electron microscopy showed that collagen fibrils of the amnion were abundant, closely packed, and well organized on Days 18-20, whereas on Day 21 they were few in number, widely spaced, and disorganized. Similar changes were present after incubation with chondroitinase ABC. In addition, amniotic epithelial cells were moribund and delaminating, basal laminae were deteriorating or absent, and few cells were at the outer surface of the amnion. All changes preceded parturition. We conclude that the structural integrity of rat fetal membranes is impaired before birth through the loss of connective tissue components and cells, changes that presumably underlie membrane rupture. Lastly, the similarity of structural changes in rat and human fetal membranes point to the potential usefulness of the rat model.

Amnion↗
PubMed1994

Cloning of a complementary deoxyribonucleic acid encoding the murine homolog of the very low density lipoprotein/apolipoprotein-E receptor: expression pattern and assignment of the gene to mouse chromosome 19.

We report the cloning of a complementary DNA for the mouse homolog of the very low density lipoprotein (VLDL)/apolipoprotein-E receptor (VLDLR), the deduced amino acid sequence of the protein, and the mapping of the gene encoding the receptor to mouse chromosome 19. Northern hybridization revealed that the VLDLR messenger RNA (mRNA) is most abundant in skeletal muscle, heart, kidney, and brain. It was also detected in lung and in low levels in liver, but it was not found in spleen or testes. Levels of VLDLR mRNA in mouse placenta increased from days 8-18 of gestation. The VLDLR mRNA was induced in 3T3-L1 cells undergoing differentiation into adipocytes. The increase in VLDLR mRNA paralleled the rise in lipoprotein lipase and hormone-sensitive lipase mRNAs. However, VLDLR and low density lipoprotein receptor-related protein were increased in the presence of retinoic acid, whereas the induction of lipoprotein lipase and hormone-sensitive lipase mRNAs was inhibited. Our observations demonstrate regulated expression of the VLDLR gene in placenta and adipocytes, where the receptor protein may play roles in the uptake of triglyceride-rich particles for storage of lipid (adipocytes) or for lipid transport to the fetus (placenta). The availability of a murine complementary DNA probe and the knowledge of the map position of the VLDLR gene in the mouse genome will facilitate studies on the function and regulation of this protein.

3T3 Cells↗
PubMed1993

Toward a nursing practice research method.

This article promotes a structure for nursing research in which the primary feature is the nurse researcher-as-clinician in a collaborative relationship with the client-as-subject. Elements of a theoretical rationale for blending the roles of clinician and researcher in an essentially qualitative methodology are developed. A nursing practice research method is conceptualized not as merely a technical activity with a focus on narrative data, but also as an explicit recognition of research as practice with an emphasis on intersubjectivity and dialogue in the research process as constitutive of reality. Research and knowledge development are thus envisioned as taking place from within the nursing situation and contingent on the quality of the nurse-client relationship. The nurse and client are recognized as the authors of the nursing-research situation in which meanings of health experiences are explored and chosen, and opportunities for enhanced quality of life are presented to both. Nurse and client each lend a unique perspective in the shared nursing-research situation. Regardless of the facticities of the client's medical status, both nurse and client have the potential for positive growth and change when these unique perspectives of nurse and client are joined. The proposed nursing practice research methodology capitalizes on these features of the practice situation, and thus, speaks directly to the concerns of the clinician.

Clinical Competence↗
PubMed1993

Qualitative research proposals and reports.

In essence, a well-developed qualitative proposal provides: 1. A clear statement that specifies the phenomenon to be studied; 2. Documentation of a need for study, with specification of the significance of the study for nursing (or social science in general); 3. Acknowledgement of the researcher's a priori orientation(s) and perspective(s) with articulated questions about the attendant presuppositions; 4. Identification of the qualitative approach with a rationale for its selection; 5. Specification of the design with attention to: a. what data are sought, b. how and when those data will be solicited, c. how relationships with research participants will be initiated, maintained, and terminated, d. how data will be managed, e. how data will be analyzed and related to preexisting knowledge, f. how findings will be reported.

Nursing Methodology Research↗
PubMed1993

Philosophical foundations of qualitative research.

Although new and still emerging for us, qualitative research approaches have been receiving considerable attention for some time in other disciplines. Along with philosophical debates, there are debates about whether there needs to be a debate. On a philosophical level, there is irreconcilable conflict between the quantitative and qualitative paradigms. It is important to recognize this conflict, avoiding illogical compromise. Yet, proponents of each paradigm need to applaud both the existence of the other and the hybrid paradigms that inevitably are born of conflict. An apt beginning would be broader definitions of what constitutes science and research in nursing, eliminating the sense-organ bias that is so contrary to our philosophy for practice. This alone would provide qualitative nurse researchers with the sanction they need to progress in their exploration of various approaches to creating a science and a body of knowledge in, for, and about nursing practice. In the chapters to follow, readers will be introduced to several qualitative research approaches. Each approach represents an interpretation of the qualitative paradigm in nursing research, grounded in the general perspective of phenomenological philosophy. This perspective focuses on phenomena as they appear and recognizes that reality is subjective and a matter of appearances for us in our social world. Subjectivity means that the world becomes real through our contact with it and acquires meaning through our interpretations of that contact. Truth, then, is a composite of realities, and access to truth is a problem of access to human subjectivity. This perspective guides the qualitative researcher in nursing to the subject matter of lived experiences, which are the original contacts with a world, and of the processes and content of interpretation--the meaning attributions that constitute realities and perspectives for a future of possibilities in the world. Other consequences of a phenomenological perspective in research include deliberate attention to the researcher's involvement in the study, engagement of multiple modes of awareness, and creative expression of findings. The product of efforts to establish a phenomenological baseline, a thorough and accurate description of nursing phenomena (a task that remains forever incomplete), will be clarified nursing concepts. If we encourage our qualitative nurse researchers, we can look forward to enhanced relevance in theoretical and empirical comments about nursing from studies guided by a mature nursing identity.

Holistic Health↗
PubMed1993

Qualitative approaches in nursing research. Phenomenology: the method.

Anderson (1989) argued that the proper focus for phenomenological nurse researchers is working out the problems and dilemmas of doing phenomenology well, rather than pondering the possibilities of triangulated research. Among those problems are questions concerning how and when one "brackets," how the researcher's self is featured, and the issue of rigor in analysis of phenomenological data. In accord with this position, the overview of phenomenological method in this chapter reveals a need to continue development of a phenomenology that produces nursing knowledge to guide nursing practices. It has been proposed that the qualities and characteristics of the researcher-researched relationship are particularly important to reconsider. The commonalities of the various phenomenologies that are engaging nurse researchers have been emphasized; their variations serve to raise methodological questions, redirecting us to yet another look at philosophical foundations for our science. The very subject matter of phenomenology is described variously. Some phenomenologies specify that the subject matter is such experiences as being in pain, doubting treatment, hoping to be well again, recovering from illness, or preparing for discharge. However, it may also be the mode of doubting or hoping, or it may be a focus on ways that it is possible to be in the world, such as what it is like to parent a child with a chronic illness, for example. The product of phenomenological inquiry, the description of experience, is inescapably interpretive, but the extent of the interpretation is another variability among the phenomenologies. However, to the extent that the description is an effective communication of insights into human experience, its relevance is immediate and direct. As a particular qualitative approach in nursing research, phenomenology has the distinction of turning the researcher on the self, that is, on his or her own reflective and intuitive grasp of experience. The researcher's direct experience constitutes the data, whether immediate or vicarious. It also has the distinction of deliberate modification by nurses for its use in nursing. This is a fortuitous development well worth our attention as the qualitative paradigm in nursing continues to gain momentum in revolutionizing our science and our practice.

Consciousness↗
PubMed1989

A qualitative investigation of reassurance.

The findings in this exploratory investigation bear witness to the existence of good nursing practice in a system that is often criticized as inhumane. Nurses do attend to clients' emotional needs in health crises and health care situations that undermine clients' abilities to understand their experiences, to make choices, and to exercise control over their circumstances. The findings also disclose the complexity of reassurance as concept and nursing intervention. We note nevertheless a nursing style that includes physical proximity, touch, ministrations, and accompaniment over time through the experiences that threaten clients' assurance and challenge their resources. These are features of nursing practice that need to be given utmost importance through formal conceptualizations in order to preserve them in our shared nursing culture. From a research perspective, we have learned that nurses are able to describe well their experiences when asked to share in an atmosphere of expectation that experiences contribute to nursing knowledge. Qualitative approaches are especially well suited to establish such an atmosphere and to facilitate explications of nurses' work. The line of inquiry into caring as the core concept of nursing practice, which has gained the attention of nurse scholars in recent years, has enormous potential to advance humanistic nursing practice. This investigation of reassurance provides evidence of its significance for us and its relevance to the construction of knowledge about caring. Future studies of reassuring another and of being reassured using qualitative strategies contain the promise of protecting nursing expertise and contributing to its refinement.

Adolescent↗
PubMed1985

Uptake of gold- and [3H]cholesteryl linoleate-labeled human low density lipoprotein by cultured rat granulosa cells: cellular mechanisms involved in lipoprotein metabolism and their importance to steroidogenesis.

We used electron microscopy, acid hydrolase cytochemistry, and biochemistry to analyze the uptake and metabolism of colloidal gold- and [3H]cholesteryl linoleate-labeled human low density lipoprotein (LDL) by cultured rat granulosa cells. The initial interaction of gold-LDL conjugates with granulosa cells occurred at binding sites diffusely distributed over the plasma membrane. After incubation with ligand in the cold, 99.9% of the conjugates were at the cell surface but less than 4% lay over coated pits. Uptake was specific since it was decreased 93-95% by excess unconjugated LDL and heparin, but only 34-38% by excess unconjugated human high density lipoprotein. LDL uptake was related to granulosa cell differentiation; well-luteinized cells bound 2-3 times as much gold-LDL as did poorly luteinized cells. Ligand internalization was initiated by warming and involved coated pits, coated vesicles, pale multivesicular bodies (MVBs), dense MVBs, and lysosomes. A key event in this process was the translocation of gold-LDL conjugates from the cell periphery to the Golgi zone. This step was carried out by the pale MVB, a prelysosomal compartment that behaves like an endosome. Granulosa cells exposed to LDL labeled with gold and [3H]cholesteryl linoleate converted [3H]sterol to [3H]progestin in a time-dependent manner. This conversion was paralleled by increased gold-labeling of lysosomes and blocked by chloroquine, an inhibitor of lysosomal activity. In brief, granulosa cells deliver LDL to lysosomes by a receptor-mediated mechanism for the hydrolysis of cholesteryl esters. The resulting cholesterol is, in turn, transferred to other cellular compartments, where conversion to steroid occurs. These events comprise the pathway used by steroid-secreting cells to obtain the LDL-cholesterol vital for steroidogenesis.

Animals↗
PubMed1981

Cytoplasmic granules in luteal cells of pregnant and non-pregnant guinea pigs. A cytochemical study.

Secretory granules, which are released by exocytosis and are speculated to contain progesterone, have been described in luteal cells of sheep and other large domestic animals. These granules are small and densely staining. Gemmell and Stacy ('79) suggested that luteal cells of guinea pigs also contain secretory granules, although they could not document exocytosis of granule content at the fine structural level. For the present study, quantitative methods were used to reexamine the possibility that luteal cells of guinea pigs possess secretory granules. Ovaries of guinea pigs were fixed in situ by vascular perfusion at the time of maximum progesterone secretion, when such granules would be most abundant, as well as other stages. Two types of granules that might be confused with secretory granules are microperoxisomes and lysosomes. Therefore, slices of perfusion-fixed corpora lutea were incubated for the fine structural localization of a peroxisomal enzyme, catalase, or for the lysosomal enzymes, acid phosphatase (ACPase) and arylsulfatase. Other tissue was prepared for conventional electron microscopy. Granule types were classified on the basis of size, morphology, and enzyme content. Quantitation of granule types was carried out on both cytochemically reacted and conventionally prepared luteal tissue. More than 5500 microperoxisomes, 2800 lysosomes, and 1100 multivesicular bodies (MVBs) were tabulated. The results indicate that luteal cells of guinea pigs have three main types of granules: 1) Microperoxisomes, about 0.2 micrometer in diameter and containing catalase; 2) lysosomes, about 0.5 micrometer in diameter and positive for ACPase and arylsulfatase; and 3) MVBs, about 0.4 micrometer in diameter and containing small vesicles. At the time of peak steroid secretion during pregnancy and the estrous cycle, the granule population in luteal cells of guinea pigs consists of 73-80% microperoxisomes, 13-17% lysosomes, and 7-9% MVBs. These proportions are similar in tissue reacted for cytochemistry and tissue prepared by conventional means. Greater than 99% of the small 0.2-0.3 micrometer diameter granules in guinea pig luteal cells are catalase reactive. This finding eliminates from further consideration most of the prime candidates for secretory granules in these cells. Finally, neither a sequential appearance of granules nor exocytosis of secretory product was detected. Our data thus argue against the suggestion that luteal cells of guinea pig have secretory granules of the type observed in corpora lutea of large domestic animals.

Acid Phosphatase↗
PubMed1979

Surface morphology of macrophages in the regressing corpus luteum, as revealed by scanning electron microscopy.

Activated macrophages phagocytize moribund luteal cells and thus play a central role in the postpartum regression of corpora lutea in guinea pigs (Paavola, '79). When viewed by transmission electron microscopy (TEM), these luteal macrophages exhibit many surface protrusions. To characterize more fully the nature and extent of these evaginations, as well as to gain further understanding of phagocytes in their natural surroundings, luteal macrophages were studied in situ by scanning electron microscopy of regressing corpora lutea. Correlated TEM was carried out to confirm the identity of the various cell types. Even in low power scanning electron micrographs, macrophages are consipicuous, and can be readily distinguished from luteal cells by their surface topography. Luteal cell surfaces bear low ridge-like folds and sparse microvilli. In contrast, macrophages characteristically exhibit highly developed surface projections, the most common of which are knob-like or clubbed processes of varying size and shape. Other distinctive surface modifications displayed by luteal macrophages include long, slender filopodia, and well developed pseudopodia. These processes generally have an uneven distribution over the cell; thus, luteal macrophages may appear polarized with regard to surface activity. Both filopodia and pseudopodia occur in close contact with luteal cell surfaces. In addition, occasional luteal macrophages have surfaces that are covered with large, crater-like depressions. The phagocytosis of cells and cellular debris by macrophages was also observed. In summary, the highly pleomorphic surface activity of luteal macrophages appears to be correlated with their role in the removal of senescent luteal cells.

Animals↗
PubMedDate not supplied

Student placements as a creative solution to the nursing shortage.

This article combines a case presentation of a university affiliation with a home care agency and a study of the perceptions of district nurses in the agency regarding client and student interactions. Overwhelmingly, district nurses found having student placements positive. However, some concerns are expressed.

Community Health Nursing↗