Biomedical subjects

G Grant

Publications and source records attributed to G Grant.

At least 127 records · Page 7Linked to original sources

PubMed1993

Action research and quality of care: a mechanism for agreeing basic values as a precursor to change.

This paper describes the trend apparent in nursing and other practice disciplines towards more participative and collaborative methods of enquiry as exemplified by action research. In so doing it notes the conceptual similarities between action research, change theory and quality initiatives. Particular attention is focused on the need to establish the basic values which provide the impetus and direction for subsequent activity. The difficulties this may pose are illustrated by reference to the application in two continuing care hospital wards for elderly patients of a checklist operationalizing a typology of care. A mechanism to facilitate and make explicit the values underpinning care in any given environment is suggested.

Aged↗

PubMed1993

Rust out and therapeutic reciprocity: concepts to advance the nursing care of older people.

This paper considers the issue of the quality of nursing care for frail elderly patients in continuing-care environments. The continued failure to raise the standards of such care is explored and potential explanations sought. It is argued that the application of models of nursing do not represent the best solution and that there is a need for a fundamental re-appraisal of sources of job satisfaction for nurses working with such patients. Using the results of an evaluation of a respite care service two concepts, 'rust out' and 'therapeutic reciprocity', are identified as offering the basis for future research, education and practice developments in this field.

Aged↗

PubMed1993

Service evaluation: time to open both eyes.

This paper draws attention to issues raised by the present emphasis on service evaluation. It highlights in particular the limitation of many current models and argues the need to adopt a broad approach which takes account of the potentially disparate views of differing interest groups. The central tenets of a pluralistic model are presented and the benefits of such an approach are illustrated by reference to a recent evaluation of a respite care scheme for elderly people and their carers.

Clinical Competence↗

PubMed1993

Antinutritive effects of wheat-germ agglutinin and other N-acetylglucosamine-specific lectins.

Incorporation of N-acetylglucosamine-specific agglutinins from wheat germ (Triticum aestivum; WGA), thorn apple (Datura stramonium) or nettle (Urtica dioica) rhizomes in the diet at the level of 7 g/kg reduced the apparent digestibility and utilization of dietary proteins and the growth of rats, with WGA being the most damaging. As a result of their binding and endocytosis by the epithelial cells of the small intestine, all three lectins were growth factors for the gut and interfered with its metabolism and function to varying degrees. WGA was particularly effective; it induced extensive polyamine-dependent hyperplastic and hypertrophic growth of the small bowel by increasing its content of proteins, RNA and DNA. Furthermore, an appreciable portion of the endocytosed WGA was transported across the gut wall into the systemic circulation, where it was deposited in the walls of the blood and lymphatic vessels. WGA also induced the hypertrophic growth of the pancreas and caused thymus atrophy. Although the transfer of the gene of WGA into crop plants has been advocated to increase their insect resistance, as the presence of this lectin in the diet may harm higher animals at the concentrations required to be effective against most pests, its use in plants as natural insecticide is not without health risks for man.

Acetylglucosamine↗

PubMed1993

Pancreatic enlargement is evident in rats fed diets containing raw soybeans (Glycine max) or cowpeas (Vigna unguiculata) for 800 days but not in those fed diets based on kidney beans (Phaseolus vulgaris) or lupinseed (Lupinus angustifolius).

Pancreatic weights and composition were studied with rats fed diets containing raw legume seeds for up to 800 d. Rapid pancreatic enlargement was induced by dietary soybeans (Glycine max) (high Kunitz and Bowman-Birk trypsin inhibitor contents, moderate lectin content) during the initial 150 d. Over the next 200 d the rate of pancreatic growth was similar to that in controls. After 350 d a second period of rapid pancreatic growth occurred. Macroscopic pancreatic nodules were evident in a number of rats fed soybeans for 500 d or more. A similar pattern of pancreatic growth was observed in rats fed dietary cowpeas (Vigna unguiculata) (high Bowman-Birk inhibitor content, low lectin content). Extensive pancreatic growth was also found in young rats fed moderate dietary levels of kidney beans (Phaseolus vulgaris) (low Bowman-Birk inhibitor content, high lectin content). However, the trophic effects diminished with time, and from 100 d onwards, little enlargement was evident. Consumption of a lupinseed (Lupinus angustifolius) diet (low trypsin inhibitor, low lectin content) did not cause pancreatic enlargement. The initial pancreatic growth induced by dietary soybeans seemed to be due to the lectins and trypsin inhibitors, whereas the second period of pancreatic growth was possibly due primarily to the trypsin inhibitors.

Analysis of Variance↗

PubMed1993

Kidney bean lectin-induced Escherichia coli overgrowth in the small intestine is blocked by GNA, a mannose-specific lectin.

The reversible and dose-dependent hyperplastic growth of the small intestine and accelerated epithelial cell turnover caused by feeding rats with diets containing kidney bean lectin (PHA) increased the proportion of immature cells on the villi whose membrane and/or cytoplasm contained mainly simple, polymannosylated glycans. These new alpha-linked mannosyl terminals, particularly of the damaged epithelium, facilitated the preferential adherence of opportunistic Escherichia coli with mannose-sensitive Type 1 fimbriae, and other coliforms, to the glycocalyx. Accordingly, the growth of the gut was accompanied by a reversible and PHA dose-dependent overgrowth with E. coli. As expected from their common carbohydrate specificity, the inclusion in the diet of the mannose-specific agglutinin from snowdrop (Galanthus nivalis) bulbs (GNA) significantly reduced the extent of E. coli overgrowth, but abolished neither the growth nor the damage caused by PHA to the small intestine. Thus, GNA and perhaps other mannose-specific lectins, especially when used in a preventive mode, can be used to specifically block the proliferation of Type 1 E. coli in the small intestine.

Animals↗

PubMed1992

Demonstration of transganglionically transported choleragenoid in rat spinal cord by immunofluorescence cytochemistry.

Injections of the B-subunit of cholera toxin (CTB) were made into the sciatic nerve of the rat. Following a survival of 2-3 days, the fluorescent antibody technique was used to show that CTB can be utilized as a highly sensitive immunocytochemically detectable transganglionic tracer for primary afferent fibers in the spinal cord. CTB-labeled fibers as well as fibers containing calcitonin gene-related peptide- (CGRP-) or substance P-like immunoreactivity were visualized simultaneously by using different fluorochromes. However, no double labeled fibers were found.

Animals↗

PubMed1992

Alterations in the level of insulin receptor and GLUT-4 mRNA in skeletal muscle from rats fed a kidney bean (Phaseolus vulgaris) diet.

1. A decline in the level of circulating insulin was observed in rats fed a diet containing kidney bean. 2. Consumption of a diet containing kidney bean caused an increase in the level of mRNAs for the insulin receptor (327%) and GLUT-4 (185%) in the gastrocnemius muscle. In contrast there was only a small increase in the amount of actin mRNA (125%). Since the kidney bean-fed rats are euglycaemic the results suggest that insulin receptor and GLUT-4 mRNA levels are regulated in response to circulating insulin concentrations rather than glucose. 3. No increases in the level of insulin receptor and actin mRNA were evident in the soleus muscle of rats fed the diet containing kidney bean; however a decline was observed in the level of GLUT-4 mRNA. 4. It is proposed that a component of kidney beans, most likely the lectin phytohaemagglutinin, has systemic effects which lead to changes in expression of the insulin receptor and GLUT-4 genes and to the sensitivity of muscle to insulin.

Actins↗

PubMed1992

Cytogenetic comparison of two poorly differentiated human lung squamous cell carcinoma lines.

This paper presents a cytogenetic analysis of two established but early-passage (passages 5 and 18) cell lines derived from histologically similar, poorly differentiated lymph node metastases of squamous cell carcinoma of the lung. The cell lines showed 3 shared marker chromosomes, del(1)(q11), del(2)(p11.1) and del(2)(q11.1). One of the lines (DLKP) had 8 additional markers including structural rearrangements such as translocations and isochromosomes. Five additional markers (including two deletions of chromosome 3) were found in DLRP. A notable feature of DLRP was the high incidence of telomeric association evident in the majority of metaphase plates. Over-representation of chromosome 7 was a characteristic feature of metaphases derived from DLKP, and identification of i(21q) in this cell line was an unusual finding. The results indicate significant cytogenetic heterogeneity between these early-passage cell lines derived from two apparently histologically similar tumors.

Carcinoma, Squamous Cell↗

PubMed1992

Changing pattern of c-FOS expression in spinal cord neurons after electrical stimulation of the chronically injured sciatic nerve in the rat.

Immunocytochemical technique was used to study the distribution of c-FOS protein immunoreactive cells in the spinal cord and gracile nuclei 2 h after electrical stimulation of the sciatic nerve in ketamine/xylazine/acepromazine-anesthetized adult rats. Quantitative examination of the c-fos-labeled cells in the spinal cord laminae was made in unoperated and sham operated controls, after sciatic nerve transection without electrical stimulation, and after electrical stimulation at C-fiber or A alpha/beta-fiber intensity, both in normal animals and at various survival times after chronic sciatic nerve injury (transection and ligation) or crush. Unoperated animals showed very few c-fos-labeled cells, and sham operated controls showed labeled cells located mainly outside the sciatic nerve projection territory. A small increase in number of c-fos protein positive cells was seen after sciatic nerve transection without electrical stimulation. Stimulation of the normal sciatic nerve at C-fiber intensity resulted in c-fos protein-positive cells within the sciatic projection territory in the ipsilateral dorsal horn. Labeled cells were seen in all spinal cord laminae except lamina IX, with the vast majority in lamina I and outer lamina II. No labeled cells were seen in the gracile nucleus. Stimulation at A alpha/beta fiber intensity resulted in no or only a very small number of c-fos-positive neurons. Electrical stimulation of the injured sciatic nerve at C-fiber intensity, using the uninjured contralateral side as control, resulted in significant decreases in c-fos-immunoreactive cells in lamina I plus the outer portion of lamina II at 12 and 39 days survival after injury. A non-significant decrease was seen in these laminae also after 21 days. Significant increases were seen in laminae III and IV at 21 days. Decreases in laminae V, VI and more ventral laminae were significant at 21 and 39 days after injury. At longer survival times, the difference between the normal and injured side seen weeks after injury tended to disappear. Stimulation at A alpha/beta fiber intensity 21 days after injury resulted in increases in the numbers of labeled cells in ipsilateral laminae II, III and IV and in the gracile nucleus. Sciatic nerve stimulation after crush injury resulted in more variable side differences, with tendencies for the same alterations as those noted after chronic transection-ligation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1992

Mineral excretion of rats fed on diets containing faba beans (Vicia faba L.) or faba bean fractions.

The effects on faecal mineral excretion of two commercial varieties (local cultivar and Troy cultivar) of raw faba beans (Vicia faba L., minor) meal (VFM) and its fractions have been studied in growing rats. Diets contained local-VFM (dark seed coat) and Troy-VFM (light seed coat) at 474-500 g/kg diet, hull (VFH) from both varieties at 65 g/kg diet, and the insoluble cotyledon residue (VFCR) obtained from the Troy variety at 237 g/kg diet. Rats were pair-fed on diets which had been supplemented with amino acids to target requirements and contained similar amounts of zinc, manganese, iron and copper. With VFM diets the apparent absorption of Zn and Mn was significantly reduced. On the other hand, with hulls the apparent absorption of Fe was reduced while that of Cu slightly increased. As the amounts of calcium, phosphorus and magnesium in VFM and VFH diets were higher than in the controls, the increased intake resulted in a significant increase in both the apparent absorption and the faecal excretion of these minerals. The inclusion of VFCR in the diet had no significant effect on the mineral content of faeces. The relatively low concentrations of phytate in the bean seeds of 7.8 and 6.7 g/kg for the local and Troy cultivars respectively, could not adequately account for the increased mineral excretion. The results suggest that other seed constituents, possibly the soluble non-starch polysaccharides, may be involved in the elevated loss of Zn and Mn in rats fed on diets containing faba bean for extended periods, while some insoluble structural hull components may interfere with the absorption of Fe from the gut.

Animals↗

PubMed1992

Nutritional evaluation of the trypsin (EC 3.4.21.4) inhibitor from cowpea (Vigna unguiculata Walp.).

The effect of feeding rats purified cowpea (Vigna unguiculata Walp.) trypsin (EC 3.4.21.4) inhibitor in a semi-synthetic high-quality diet based on lactalbumin (10 g inhibitor/kg) for 10 d was a moderate reduction in the weight gain of rats in comparison with controls, despite an identical food intake in the two groups. The reduction in the growth rate was about 20% on a live weight basis. However, the corresponding value calculated from the weight of dry carcasses was less, only about 7%, probably because the water content of the body of the two groups of rats was different. Although most of the cowpea trypsin inhibitor (CpTI) was rapidly broken down in the digestive tract, its inclusion in the diet led to a slight, though significant, increase in the nitrogen content of faeces but not of urine. Accordingly, the net protein utilization of rats fed on inhibitor-containing diets was also slightly depressed while their energy expenditure was elevated. In agreement with results obtained for the protease inhibitors of soya bean, the slight anti-nutritional effects of CpTI were probably due mainly to the stimulation of the growth and metabolism of the pancreas. Thus, the nutritional penalty for increased insect-resistance after the transfer of the cowpea trypsin inhibitor gene into food plants is slight in the short-term.

Animals↗

PubMed1992

Mid-range theory building and the nursing theory-practice gap: a respite care case study.

Nursing, with its historical roots in practice, has tended to have an uneasy relationship with theory. Whilst the benefits of theory to nursing have been propounded by many commentators, it remains that theory all too rarely informs nursing practice. This paper argues for the development and utilization of mid-range theories as representing a solution to this problem. The advantages of such an approach are illustrated by the application, testing and refinement of Chenitz's theory of relocation to a hospital-based respite care scheme for the frail elderly.

Adaptation, Psychological↗

PubMed1992

Effect of the beta-adrenoceptor agonist clenbuterol and phytohaemagglutinin on growth, protein synthesis and polyamine metabolism of tissues of the rat.

1. The kidney bean lectin, phytohaemagglutinin (PHA), induced a marked atrophy of skeletal muscle which was evident from the changes in tissue composition (protein, RNA, DNA and polyamine content) and from the reduction in weight and protein synthesis of hind leg muscles of rats fed on kidney bean-diets for four days. The beta-adrenoceptor agonist, clenbuterol, induced skeletal muscle hypertrophy by transiently stimulating protein synthesis. As a consequence, the muscle loss caused by a short exposure to PHA was, in part, ameliorated by clenbuterol treatment. 2. Cardiac muscle was affected to a lesser extent than skeletal muscle by both clenbuterol and the lectin. However, there was evidence that protein synthesis in heart was reduced by PHA. 3. PHA had opposite effects on the gut, the lectin-induced hyperplasia of the jejunum was accompanied by a large increase in protein synthesis. Clenbuterol alone had no effect on the jejunum whereas a combination of PHA and clenbuterol appeared to exacerbate the effect of the lectin on gut. 4. Both the lectin-induced gut growth and the hypertrophy of skeletal muscle caused by clenbuterol were preceded by the accumulation of polyamines in the respective tissues. Of particular note was the observation that a significant increase in the proportion of the intraperitoneally injected 14C-labelled spermidine or putrescine taken up by the growing tissues could be detected by the second day. Therefore, the measurement of uptake of labelled polyamines may be used as a sensitive indicator of early alterations in tissue metabolism.

Animals↗

PubMed1992

Urea synthesis in rats fed diet containing kidney beans.

When rats were fed a diet containing kidney bean (Phaesolus vulgaris) urea excretion was increased 3-5 fold. Isolated liver mitochondria from rats fed the kidney bean diet produced 40% more citrulline in the presence of arginine than mitochondria isolated from control rats. Mitochondrial activities of urea cycle enzymes and N-acetylglutamate synthetase were similar in animals fed diets containing kidney bean or lactalbumin. The possible mechanisms causing acute urea production in rats fed with kidney bean are discussed.

Acetyltransferases↗

PubMed1991

Choleragenoid horseradish peroxidase used for studying projections of some hindlimb cutaneous nerves and plantar foot afferents to the dorsal horn and Clarke's column in the rat.

The aim of the present study has been to investigate the spinal projections of cutaneous hindlimb afferents particularly to the deep dorsal horn and to Clarke's column (CC), by using the B-subunit of cholera toxin conjugated to horseradish peroxidase. Injections into three different cutaneous hindlimb nerves in adult rats resulted in dense labeling in the dorsal horn laminae IIi-IV/V, moderate labeling in lamina I and modest labeling in dorsomedial parts of CC. Footpad injections gave similar results, except for a lack of labeling in CC and only weak labeling in laminae I and V. The results suggest that B-HRP should be a useful marker for studying cutaneous myelinated nerve fiber projections to the rat spinal cord.

Afferent Pathways↗

PubMed1991

Topographic relationship between sagittal Purkinje cell bands revealed by a monoclonal antibody to zebrin I and spinocerebellar projections arising from the central cervical nucleus in the rat.

We have examined the topographic relationship between the sagittal bands of zebrin I immunoreactive Purkinje cells revealed by a monoclonal antibody, mabQ113, and the distribution of spinocerebellar fibers originating from the central cervical nucleus in the rat. The mossy fiber terminals were anterogradely labeled following injections of cholera toxin subunit B into the C1-C3 segments and visualized immunohistochemically. Zebrin I positive Purkinje cells appeared in seven sagittal bands (P1+ to P7+ bands). In lobules I-V of the anterior lobe, labeled mossy fiber terminals were distributed in the midline region, subjacent to the P1+ bands and at around 0.5 mm from the midline region, subjacent to the P2+ band in the lateral A1 to the medial A2 zones of Voogd et al. (1985). Labeled terminals were seen in the entire B zone and those distributed in its medial part were related to the P3+ band. In lobule VIII, labeled terminals were seen subjacent to the P1+, P2+ and P3+ bands, which were located in the lateral A1-A3 (or B) zones. In the copula pyramidis, labeled terminals appeared subjacent to the P4+, P5+ and the P6+ bands in the C1 and C2 zones (or the C1-C3 zones). Although the labeled terminals were seen beneath the zebrin I positive bands, the borders of terminal distribution were not well-delineated, and did not respect the borders of zebrin I positive bands.

Afferent Pathways↗

PubMed1991

Brainstem projections of different branches of the vestibular nerve: an experimental study by transganglionic transport of horseradish peroxidase in the cat. II. The anterior and posterior ampullar nerves.

The brainstem projections of the ampullar nerves from the vertical semicircular canals, the anterior (AAN) and the posterior ampullar nerve (PAN), were studied in adult cats using the transganglionic horseradish peroxidase (HRP) method. Each nerve was exposed in three experiments. Two animals in each group had labeling which allowed detailed mapping. From the AAN, terminal-type labeling was found in two separate groups, one laterally and one medially, both in the lateral (LV) and in the superior (SV) vestibular nucleus. In addition, such labeling was found in all parts of the medial vestibular nucleus (MV). Labeled structures were found also in the descending vestibular nucleus, (DV) more densely over its lateral part, except for cell group f, where no labeling was found. From the PAN, terminal-type labeling was found medially and laterally in the LV and in the medial part of the SV. In the MV, such labeling was evenly distributed rostrally but concentrated laterally in caudal parts. In the DV, terminal-type labeling was present rostrally, whereas no labeling was seen caudally. In the interstitial nucleus of the vestibular nerve, terminal-type labeling was observed from the AAN but not from the PAN. No labeled fibers from either of the two ampullar nerves were seen outside the vestibular root and nuclei, except for small-caliber fibers from the SV heading towards the brachium conjunctivum. The findings clearly indicate a specific termination for each of the two ampullar nerves.

Animals↗