Search PubMed⌕ Search

Biomedical subjects

L Scott

Publications and source records attributed to L Scott.

At least 37 records · Page 2Linked to original sources
PubMed1999

Microvolume fluorimetry for the determination of absolute CD4 and CD8 lymphocyte counts in patients with HIV: a comparative evaluation.

This study compared CD4 and CD8 lymphocyte counts obtained by microvolume fluorimetry (MVF) with those derived by flow cytometry (FC). Samples from 192 patients with known or suspected HIV were analysed, and the distribution of CD4 counts for these samples ranged from 0 and 1,279/microl, with 142/192 (74%) of the samples having CD4 values of less than 400/microl. Good agreement between FC and MVF CD4 counts was found (MVF = 0.98 x FC + 7.30) although there was a minor constant inter-method bias of approximately +7 cells/microl for the MVF data. For CD8 counts there was a constant bias between the two methods of approximately +23 cells/microl for FC. Most outliers were associated with higher FC CD8 counts. Supplementary analyses showed a high level of agreement between FC and MVF methods for the CD4:CD8 ratios (MVF = 0.98 x FC). This suggests that observed discrepancies between FC and MVF methods were almost certainly a result of the influence of the absolute lymphocyte counts obtained from the haematology analyser. The results confirm that the IMAGN 2000 microvolume fluorimeter system can be used as an alternative to conventional flow cytometry for the enumeration of CD4 and CD8 counts.

CD4 Lymphocyte Count↗
PubMed1999

The nature and structure of supervision in health visiting with victims of child sexual abuse.

RATIONALE: Part of a higher research degree to explore professional practice. AIM: To explore how health visitors work with victims of child sexual abuse and the supervision systems to support them. OBJECTIVE: To seek the views and experiences of practising health visitors relating to complex care in order to consider the nature and structure of supervision. METHODOLOGY: The research reported in this paper used a qualitative method of research and semi-structured interviews with practising health visitors of varying levels of experience in venues around England. Qualitative research enabled the exploration of experiences. OUTCOMES: Identification of the need for regular, structured, accountable opportunities in a 'private setting' to discuss whole caseload work and current practice issues. RESULTS: Supervision requires a structured, formalized process, in both regularity and content, as a means to explore and acknowledge work with increasingly complex care, to enable full discussion of whole caseloads. Supervision is demonstrated as a vehicle to enable the sharing of good practices and for weak practices to be identified and managed appropriately. Supervision seeks to fulfil the above whilst promoting a stimulating, learning experience, accommodating the notion that individuals learn at their own pace and bring a wealth of human experience to the service. STUDY LIMITATIONS: The size of the study was dictated by the amount of time available within which to complete a research master's degree course primarily in the author's own time, over a 2-year period. The majority of participants volunteered their accounts in their own time. For others I obtained permission from their employers for them to participate once they approached me with an interest in being interviewed. CONCLUSIONS: This research provides a model of supervision based on practitioner views and experiences. The article highlights the value of research and evidence-based information to enhance practice accountability and the quality of care. Proactive risk management can safeguard the health and safety of the public, the practitioner and the organization.

Child↗
PubMed1999

Compartmentalisation of the developing trigeminal ganglion into maxillary and mandibular divisions does not depend on target contact.

During development axons contact their target tissues with phenomenal accuracy but the mechanisms that control this homing behaviour remain largely elusive. A prerequisite to the study of the factors involved in hard-wiring the nervous system during neurogenesis is an accurate calendar of developmental events. We have studied the maxillary and mandibular components of the trigeminal system to determine the stages during embryogenesis when a gross somatotopic order is first established within the trigeminal ganglion and the axons projecting to the brainstem. The retrograde transganglionic fluorescent tracers DiO and DiI were injected into the maxillary and mandibular arches or their derivatives in fixed mouse embryos staged between 13 and 40 somites (E9-E11). After 1-4 wk, the distribution of the 2 tracers was determined using confocal laser scanning microscopy. The first maxillary nerve cell bodies and their developing axons were labelled at the 30 somite stage (E10). This was 2 somite stages earlier than the mesencephalic nucleus and the ganglion cell bodies of the mandibular nerve. The gross somatotopic division of cells within the trigeminal ganglion projecting to the maxillary and mandibular targets was established by the 32 somite stage (E10). This arrangement was evident as 2 groups of cell bodies occupying adjacent but separate regions of the trigeminal ganglion. The central branches of the maxillary and mandibular cell bodies entered the metencephalon as 2 distinct bundles at the same stage. The trigeminal motor nucleus was first detected at the 38 somite stage (E10.5). Gross somatotopy in the major divisions of the trigeminal ganglion is established before outgrowing axons have contacted their peripheral target tissue at E10.5. This suggests that target tissues do not induce somatotopy.

Animals↗
PubMed1999

Decreasing ascorbate intake does not affect the levels of glutathione, tocopherol or retinol in the ascorbate-requiring osteogenic disorder shionogi rats.

Levels of glutathione in liver and kidney, and other nutrients in plasma were evaluated in male and female ascorbate-requiring osteogenic disorder Shionogi (ODS) rats fed semipurified diets in which the concentrations of ascorbate were gradually decreased from 1965 to 180 mg/kg. Plasma ascorbate levels in ODS rats were unaffected when ascorbate levels in the diet were decreased from 1965 to 768 mg/kg. However, plasma ascorbate levels decreased progressively when levels of ascorbate in the diet were decreased from 527 to 180 mg/kg. Plasma ascorbate levels decreased up to 77% when the dietary ascorbate concentration decreased from 1965 to 180 mg/kg. Ascorbate levels in liver and kidney fell as much as 60-70% when the dietary ascorbate levels were reduced from 1965 to 180 mg/kg. However, the glutathione levels in these tissues were not affected. Plasma retinol and vitamin E levels were not affected by decreasing dietary ascorbate intake. Total cholesterol levels increased significantly in female rats as dietary ascorbate intake declined. Levels of glycated hemoglobin decreased significantly when dietary ascorbate levels decreased from 1965 to 527 mg/kg. This study suggests that levels of vitamin E, retinol and glutathione are not affected by decreased dietary intake of ascorbate under nonscorbutic conditions, whereas elevated ascorbate intake is associated with a decrease in levels of plasma cholesterol in female ODS rats. However, excessive intake of ascorbate may be associated with elevated glycation of hemoglobin. To achieve the maximal health benefit of ascorbate supplementation, further studies are necessary to define optimal ascorbate intakes.

Administration, Oral↗
PubMed1999

Patient satisfaction with emergency department triage nursing care: a multicenter study.

This descriptive, correlational study examines relationships between (1) individual patient and nurse characteristics and (2) patient satisfaction with triage nursing care, patient satisfaction with the triage nurse, and patient's intention to return to a specific Emergency Department. The convenience sample consisted of Urgent/Delayed patients (N = 378) triaged in an urban academic medical center, a public hospital in a small city, and a Catholic hospital in a small city. Analysis of variance revealed significantly higher levels of patient satisfaction at the academic medical center, whereas higher levels of intent to return were reported by subjects from the Catholic-affiliated hospital. Educational preparation of the triage nurse was identified as a significant predictor of both patient satisfaction with triage nursing care and loyalty to a specific.

Adult↗
PubMed1999

Sleep-induced changes in associative memory.

The notion that dreaming might alter the strength of associative links in memory was first proposed almost 200 years ago. But no strong evidence of such altered associative links has been obtained. Semantic priming can be used to quantify the strength of associative links between pairs of words; it is thought to measure the automatic spread of activation from a "node" representing one word to nodes representing semantically related words. Semantic priming could thus be used to test for global alterations in the strengths of associative links across the wake-sleep cycle. Awakenings from REM and nonREM (NREM) sleep produce a period of state carry-over during which performance is altered as a result of the brain's slow transition to full wakefulness, and cognitive testing in this period can provide information about the functioning of the brain during the prior sleep period. When subjects were tested across the night--before and after a night's sleep as well as immediately following forced awakenings from REM and NREM sleep--weak priming (e. g., thief-wrong) was found to be state dependent (p = 0.016), whereas strong priming (e.g., hot-cold) was not (p = 0.89). Weak primes were most effective in the presleep and REM sleep conditions and least effective in NREM and postsleep conditions. Most striking are analyses comparing weak and strong priming within each wake-sleep state. Contrary to the normal pattern of priming, subjects awakened from REM sleep showed greater priming by weak primes than by strong primes (p = 0.01). This result was seen in each of three protocols. In contrast, strong priming exceeded weak priming in NREM sleep. The shift in weak priming seen after REM sleep awakenings suggests that cognition during REM sleep is qualitatively different from that of waking and NREM sleep and may reflect a shift in associative memory systems, a shift that we hypothesize underlies the bizarre and hyperassociative character of REM-sleep dreaming. Known changes in brainstem activity that control the transition into and maintenance of REM sleep provide a possible explanation of this shift.

Adult↗
PubMed1998

Target pioneering and early morphology of the murine chorda tympani.

Many studies demonstrate that differentiation of certain sensory receptors during development is induced by their nerve supply. Thus the navigational accuracy of pioneering fibres to their targets is crucial to this process. The special gustatory elements of the facial and glossopharyngeal nerves are used extensively as model systems in this field. We examined the chorda tympani, the gustatory component of the facial nerve, to determine the precise time course of its development in mice. The transganglionic fluorescent tracer DiI was injected into the anterior aspect of the mandibular arch of fixed embryos aged between 30 and 50 somites (E10-E12). It was allowed to diffuse retrogradely via the geniculate ganglion to the brainstem for 4 wk, before the distribution of DiI was determined using confocal laser scanning microscopy. Geniculate ganglion cells were first labelled at the 34 somite stage (E10). Pioneering chorda tympani fibres that arise from these cells passed peripherally and followed an oblique course as they grew towards the mandibular arch. At the 36 somite stage (E10.5), the peripheral component followed an intricate postspiracular course and passed anteriorly to arch over the primitive tympanic cavity, en route to the lingual epithelium. From the 36 to 50 somite stages (E10.5-E12), it consistently traced in the fashion of a 'U' bend. The central fascicle also traced at the 36 somite stage (E10.5) and just made contact with the brainstem. At the 40 somite stage (E11), the central fibres clearly chose a route of descent into the spinal trigeminal tract and branched into the solitary tract. Pioneering chorda tympani fibres contact the lingual epithelium when the target is primordial. The lingual epithelium may be a source of a neurotropic factor that attracts peripheral chorda tympani fibres to the sites of putative papillae. However, the chorda tympani is probably not a vital influence on the subsequent differentiation of gustatory papillae, since the papillae are elaborated 5 d later at E15 in murine embryos. The early morphology of the nerve is true to the amniote vertebrate phenotype.

Animals↗
PubMed1997

Iowa relaxes CON.

Explore the source record for details and available documents.

Capital Expenditures↗