Search PubMed⌕ Search

Biomedical subjects

C S Scott

Publications and source records attributed to C S Scott.

At least 55 records · Page 3Linked to original sources
PubMed1995

Evaluating students' substance abuse assessment skills.

Graduating nursing students' abilities to assess clients for substance use were evaluated using two standardized patient (SP) cases. In the comprehensive health history case (unprompted), 55% of the study participants assessed alcohol use and 20% assessed drug use. When prompted to conduct a substance use history, at least 90% of the subjects asked about the quantity and frequency of alcohol use and 80% asked about drug use. However, in the prompted case, fewer than 10% of the subjects linked current alcohol and drug (AOD) use with risks and consequences, nor did they ask the SP if he had considered decreasing substance use. The mean score for communication skills used in the two assessment interviews were 3.65 and 3.56 on a 1 to 6 Likert scale. These data point out the need for additional emphasis on instructing students to include AOD questions as part of routine assessments, what questions to ask in a substance use assessment, and how to act on the information received. The use of SPs is one way to obtain valid information about students' assessment competencies.

Adult↗
PubMed1995

Immunophenotypic and DNA genotypic analysis of T-cell and NK-cell subpopulations in patients with B-cell chronic lymphocytic leukaemia (B-CLL).

Absolute numbers and distributions of peripheral blood T-cells and NK cells were immunophenotypically determined in 21 patients with B-CLL and compared with those obtained from a series of 13 elderly normal controls with an age range of 60-87 years. For absolute CD3+, CD4+ and CD8+ T-cell, and CD16+ NK subpopulation numbers, there were no consistent differences between the normal and B-CLL groups although some individual patient variation was seen. Immunophenotypic analyses did however reveal that CD3+ T-cells in almost half (10/21) of the B-CLL patients were Ia+ (defined as > 20% positive cells), compared to 0/13 of the elderly control group (p < 0.001), and that the proportions of CD4+ and CD8+ cells expressing membrane CD45RO were significantly increased compared to the control group. Subdivision of the B-CLL cases into those with low (< 20%) and high (> 20%) proportions of CD3+ T-cells co-expressing Ia further showed that CD45RO expression by CD4+ fractions was particularly prominent in the Ia+ subgroup, and that the relative increase of CD4+CD45RO+ cells was primarily a consequence of decreased absolute numbers of CD4+CD45RA+ lymphocytes. This study also examined extracted DNA from enriched CD3+ T-cell fractions (obtained by immunomagnetic bead selection in 9 of the B-CLL cases) by PCR analysis with two primers for the T-cell gamma gene locus. With the V gamma C (consensus) primer, 8/9 cases were polyclonal and the remaining case was oligoclonal. For comparison, 7/9 CD3+ fractions were oligoclonal with the V gamma 9 primer with the other two cases being polyclonal. No monoclonal CD3+ components were found. It is suggested that the observed increased Ia expression by CD3+ cells and the predominance of CD4+ cells expressing membrane CD45RO in patients with B-CLL may be of potential relevance to understanding the pathogenesis and patterns of disease progression.

Aged↗
PubMed1995

Clonal CD3+CD8+ large granular lymphocyte (LGL)/NK-associated (NKa) expansions: primary malignancies or secondary reactive phenomena?

This study reports the clinical, haematological and immunophenotypic features of a series of 25 patients with clonal expansions of large granular lymphocytes (LGL)/NK-associated (NKa) cells. These showed a male predominance (16:9) with a median age of 67 (range 38-91) years; four had a documented history of rheumatoid arthritis, a further 18 had diverse clinical disorders, and the remaining three were clinically well. Mild anaemia was found in approximately half the patients and a lymphocytosis (seen in approximately 70% of the cases) was usually modest (< 10.0 x 10(9)/l). Neutropenia was the most frequently observed feature, and this was typically persistent in nature. Serum studies revealed few consistent features although positive rheumatoid factor and increased soluble CD8 levels were noted in 67% and 87% of those cases tested. Phenotypically, all cases were CD2+CD3+CD8+ and expressed membrane TCR alpha beta chains; most (17/22) were additionally CD5+ and (19/22) CD7+. The staining intensities of CD5 and CD7 antigens were however lower than that of normal CD4+ and CD8+ blood lymphocytes. Expression of NKa antigens was variable although 16/22 cases were CD16+CD56- and 19/22 were CD57+. Clonal CD3+CD8+ LGL/NKa expansions with a CD16+CD56+ composite phenotype were not seen in this patient series. Analyses of 'activation' antigens showed a consistent lack of CD25 expression by CD3+ cells, but increased CD3/Ia co-expression was found in a high proportion (19/25) of cases. Studies of CD45R isoform expression by CD8+ LGL/NKa cell fractions revealed a consistent CD45RA+RO- profile for all cases tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Recommended procedures for the classification of acute leukaemias.

The classification of acute leukaemias is now widely based on a combined morphological, cytochemical and immunophenotyping approach. Difficulties are frequently encountered however in reaching an acceptable degree of diagnostic concordance between different laboratories because of variations in the techniques used (in terms of methodologies, reagents and equipment) and diagnostic interpretation. The International Council for Standardization in Haematology (ICSH) convened an expert panel to consider currently available diagnostic techniques with the aim of defining a minimum cytochemical and immunological diagnostic panel that could be used as core components for the classification of acute leukaemia. The proposed ICSH scheme, which attempts to balance the basic requirement for providing precise and informative diagnostic information without limiting its use to only those laboratories with sophisticated facilities, is based on three sequential levels of investigation; primary cytochemistry, intracellular phenotyping and membrane immunophenotyping. The minimum ICSH recommended cytochemistries comprise myeloperoxidase (MPO), chloroacetate esterase (ChlorE) and alpha-naphthyl acetate esterase (ANAE), and standardised methods for these cytochemistries are detailed in this communication. For cases of acute leukaemia that remain unclassified by primary cytochemistry, subsequent immunological analyses for cytoplasmic CD3, CD22, MPO and nuclear TdT are recommended. The ICSH panel considers that the use of these minimum primary cytochemical and intracellular phenotyping procedures will lead to the consistent classification of most acute leukaemias, and that the third level of investigation (membrane immunophenotyping) should be used for the purposes of confirmation, diagnostic clarification of atypical leukaemias, and the subtyping of acute lymphoblastic leukaemias (ALL). The ICSH panel also recognised that there are a number of additional technologies which can provide definitive diagnostic information, such as cytogenetics and DNA genotyping, but these were excluded from the minimum panel because of their restricted availability. While many specialised laboratories, particularly in the areas of diagnostic research, will continue to use individual investigatory protocols, it is considered that the inclusion of the ICSH scheme as core components would lead to greater consistency when comparing independent studies of acute leukaemia.

Acute Disease↗
PubMed1994

Unique immunophenotype of acute promyelocytic leukaemia as defined by CD9 and CD68 antibodies.

Twenty-one cases of acute promyelocytic leukaemia (FAB M3) demonstrating t(15,17) chromosomal translocation were studied in detail by immunocytochemical techniques using a panel of monoclonal antibodies. A characteristic myeloid phenotype of the leukaemic cells, co-expression of CD9 and CD68 antigens and absence of HLA-DR, was noted in all cases. Although the cellular morphology of acute promyelocytic leukaemia provides the most rapid means for diagnosis, this unique leukaemic cell phenotype provides confirmatory diagnostic evidence. In view of the new therapeutic options and prognosis in acute promyelocytic leukaemia, the detection of cases with atypical morphology based on this unique phenotype would be of value. In addition, the phenotype of acute promyelocytic leukaemia is similar to that of basophils and mast cells and raises the possibility that the leukaemic cells may have undergone a degree of basophilic differentiation.

Antigens, CD↗
PubMed1994

A biclonal large granular lymphocyte (LGL)/NK-associated (NKa) disorder of CD4+ and CD8+ lymphocyte subpopulations characterized by the simultaneous presence of distinct TCR rearrangements.

This communication reports a patient with concomitant expansions of CD4+ and CD8+ large granular lymphocytes. Immunological analyses revealed that the abnormally increased CD4+ LGL fraction was phenotypically similar to other reported persistent CD4+ LGL expansions, whereas the phenotypic profile for the CD8+ LGL component was unusual. Of particular note was the finding that both the CD4+ and CD8+ LGL fractions showed high membrane CD45RO isoform expression, thus suggesting their 'primed' status. Molecular biology studies of immunomagnetically fractionated cells using a T gamma 9 TCR gamma gene primer further revealed that the CD4+ and CD8+ components were both clonal but showed different patterns of rearrangement. It is suggested that the simultaneous presence of CD4+ and CD8+ clonal populations are unlikely to have been derived from a common progenitor and that they reflect expansions of functionally restricted subpopulations.

Aged↗
PubMed1994

Clonality of CD3 negative large granular lymphocyte proliferations determined by PCR based X-inactivation studies.

AIMS: To examine persistent CD3-large granular lymphocytosis (LGL) cases for clonality, both by lineage specific (T cell receptor) and lineage independent (X-inactivation) molecular methods; and to find out whether X-inactivation studies are more appropriate than gene rearrangement studies for this subset of LGL disorders. METHODS: Patients were selected who had LGL of more than six months' duration and identified as CD3- by immunophenotyping. T cell receptor studies and, where possible, X-inactivation studies of the phosphoglycerate kinase (PGK) gene were carried out. Analysis of subpopulations was carried out on cases heterozygous for PGK by the use of a polymerase chain reaction (PCR) method for X-inactivation. RESULTS: Of 17 CD3- LGL cases studied, all were found to be germline for beta, gamma, and delta T cell receptor studies, and immunoglobulin heavy chain genes. However, six of these were analysed by X-inactivation of the PGK gene and two cases gave clonal band patterns but only within the CD3- subpopulation. CONCLUSIONS: Clonal analysis by the lineage independent method of X-inactivation allows clonal expansion undetected by T and B cell specific markers to be identified. It is therefore a more appropriate method for the analysis of CD3- LGL. This has implications for diagnosis in CD3- LGL disorders.

Adult↗
PubMed1994

Regulation of plasma vasopressin by plasma osmolality and carotid sinus pressure in anesthetized rabbits.

The purpose of the experiments was to investigate the effect of changes in carotid sinus baroreceptor stimulation on plasma vasopressin (AVP) at different plasma osmolalities in the anesthetized artificially ventilated rabbit. Both carotid sinuses were isolated and perfused with blood at servo-controlled pressures. The vagus and aortic depressor nerves were sectioned bilaterally to eliminate input from atrial and aortic arch baroreceptors. Saline (0.3%, wt/vol) was infused to lower plasma osmolality, and 5% saline was infused to raise plasma osmolality. At three plasma osmolalities, the carotid sinus pressure (CSP) was changed from 100 mmHg to 40 and 140 mmHg and returned to 100 mmHg. There were no changes in plasma AVP in response to changes in CSP at low plasma osmolality (289 mosmol/kgH2O), but at medium (309 mosmol/kgH2O) and high (323 mosmol/kgH2O) osmolality, plasma AVP was higher at 40 than at 140 mmHg CSP. The relationship between plasma AVP and plasma osmolality was expressed as a linear regression at each CSP. Changes in CSP changed the sensitivity but not the threshold of the osmotic control of AVP release.

Animals↗
PubMed1994

Persistent clonal expansions of CD3+TCR gamma delta+ and CD3+TCR alpha beta+CD4-CD8- lymphocytes associated with neutropenia.

This communication reports the clinical and cellular features of five elderly female patients with persistent moderate to severe neutropenia and concomitant relative expansions of CD3+TCR gamma delta+ (n = 4) or CD3+TCR alpha beta+CD4-CD8- (n = 1) lymphocyte populations. In clinical terms, severe neutropenia was the main contributing factor to patient symptoms although two additionally had long-standing histories of rheumatoid arthritis. The absolute lymphocyte counts did not exceed the normal upper limit in these patients, and morphologically the lymphocytes were not typically of large granular lymphocyte (LGL) type although LGL-associated BLT-esterase staining was consistently increased. Expression of NK-associated (NKa) membrane determinants (CD16, CD56 and CD57) were variable but there was an apparent correlation between weak membrane CD8 and CD16 expression. DNA genotypic studies confirmed that the four CD3+TCR gamma delta+ cases were clonal in nature and add further support to an emerging impression that expansions of these lymphocyte subpopulations may frequently be clinically associated with autoimmune phenomena in general and neutropenia in particular.

Aged↗
PubMed1993

Potential risk factors for rape in three ethnic groups.

This article describes the frequency of possible risk factors that emerged during a cross-cultural study of psychosocial response to sexual assault among African-American, Hispanic, and non-Hispanic white women presenting for treatment at a major urban rape treatment center. Of 881 victims screened, 51% had no observable risk factors while 49% fell into categories of variables that previous research has associated with increased vulnerability. Included were mental disability (psychiatric or developmental), a prior history of rape or incest, tourist or visitor status (site unfamiliarity), and homelessness. Ethnic groups differed significantly in these categories, suggesting socioeconomic and cultural variables that may affect rape statistics and that should be taken into account in rape prevention programs in the community.

Adolescent↗
PubMed1993

Cultural beliefs about rape and victims' response in three ethnic groups.

Cultural definitions of rape were assessed among 101 African-American, Hispanic, and non-Hispanic white female rape victims and 89 nonvictims matched for ethnicity, age, marital status, and socioeconomic status. Hispanics scored highest and whites lowest both in perceived community victim-blaming and in victims' psychological distress. Social and treatment implications are discussed.

Adaptation, Psychological↗
PubMed1993

Characteristics of dean's letters in 1981 and 1992.

PURPOSE: To compare results from 1981 and 1992 national surveys of the writers of medical school dean's letters, and to rate the 1992 letters based on the guidelines recommended by the Association of American Medical Colleges (AAMC). METHOD: In early 1992 a survey was administered to the dean's letter writers at all 125 U.S. medical schools with fully accredited four-year programs; the survey incorporated many items from a 1981 survey. In addition, 550 dean's letters from all U.S. medical schools for the graduating class of 1992 were collected and rated based on guidelines published by the AAMC in 1989. RESULTS: The response rate of the 1992 survey was comparable to that of the 1981 survey (85% and 87%, respectively). In both surveys, slightly more than half the schools used more than one letter writer; however, the 1992 letters were longer and there were more of them, in spite of the fact that there were approximately 700 fewer graduates. In 1992 the estimated total cost per school was $25,000 (comparable data were not collected in 1981). The ratings of the letters revealed that only 38% of the schools introduced their letters as letters of "evaluation," as recommended by the AAMC, and that 15% of the schools failed to use the AAMC guidelines for format. When the schools were rated for overall quality (i.e., format combined with information about the students' performance in comparison with that of peers), 55% of the schools passed and 45% failed. CONCLUSION: Several recommendations for improving dean's letters are discussed, including the following: (1) all dean's letters should be formatted according to the AAMC guidelines; (2) each school should have one person responsible for central overview of the school's letters; and (3) for comparative performance information, schools should at least give the percentages of grades given in the required clerkships, and it would be preferable for them to employ systems that group students into four to six groups and to indicate the percentage of students in each group.

Correspondence as Topic↗
PubMed1993

Subcellular fractionation studies indicate an intracellular localization for human monocyte specific esterase (MSE).

Human monocyte-specific esterase (MSE) is one of the few haemopoietic cell enzymes that show absolute lineage restriction. Although the function of MSE has yet to be deduced, its potential role in tumour cell killing has stimulated particular interest. Knowledge of subcellular localization of MSE is fundamental to understanding its function and, in this context, it is widely believed that MSE is expressed as a plasma membrane ectoenzyme; a contention that is largely based upon experiments which examined fixed cells by ultrastructural cytochemistry. However, as recent molecular studies of human MSE indicate, a number of inconsistencies between its structure and a membrane localization, we applied the techniques of phase separation in the non-ionic detergent Triton X-114 and differential centrifugation to further investigate whether this particular esterase species is membrane-bound or associated with an intracellular organelle. These studies provide strong evidence that MSE is in fact a soluble intracellular enzyme that is almost certainly located within the lumen of the endoplasmic reticulum.

Carboxylic Ester Hydrolases↗
PubMed1993

Transient and persistent expansions of large granular lymphocytes (LGL) and NK-associated (NKa) cells: the Yorkshire Leukaemia Group Study.

A survey of 870 different adult blood samples (primarily from patients with non-haematological disorders) found that 269 (31%) had increased proportions (> 25%) and/or absolute numbers (> 1.0 x 10(9)/l) of morphologically-defined large granular lymphocytes (LGL), and/or phenotypically-defined NK-associated (NKa) cells. Of these, 112 were re-analysed at least 6 months after initial presentation and were classified as 'persistent' (92/112) or 'transient' (20/112) according to whether or not the original abnormality was still present. Lymphocyte counts in most patients with persistent abnormalities were within normal limits (18/92) or slightly increased (68/92), with only six having a lymphocytosis exceeding 10.0 x 10(9)/l. With the exception of five persistent LGL expansions in which the granular lymphocytes did not express NKa determinants (designated LGL+NKa-), the remaining 87 cases could be phenotypically grouped according to their primary abnormality as CD8+NKa+ (n = 33), CD4+ NKa+ (n = 14), CD8dim+NKa+ (n = 7) or CD8-NKa+ (n = 33). TCR genotypic studies in 58 patients showed that the 16 patients with rearranged TCR components were restricted to the CD8+NKa+ group and that, in most of these, the CD8+ fraction showed abnormal relative CD16/CD56 expression. Persistent neutropenia (n = 15) also appeared to be associated with primary abnormalities of CD8+NKa+ cells (12/15), with 10 of these additionally showing rearranged TCR genes. In contrast, persistently increased CD8dim+NKa+ and CD8-NKa+ components did not appear to phenotypically differ from their corresponding 'counterparts' in normal bloods or in patients with transient LGL/NKa+ abnormalities. This survey has therefore established that persistent LGL/NKa+ abnormalities are considerably more common than suggested in published work, that a high proportion of patients with expanded CD8+NKa+ components, with quite diverse clinical histories, show evidence of clonal lymphoid populations, and that the clonal nature of such disorders appears to be associated with abnormal NKa phenotypic patterns.

Adult↗