Biomedical subjects

E Townsend

Publications and source records attributed to E Townsend.

At least 19 recordsLinked to original sources

PubMed2003

General practitioner contacts with patients before and after deliberate self harm.

BACKGROUND: Deliberate self harm (DSH) is an increasingly common problem. Although much attention is focused on suicide prevention by psychiatric services, the role of the general practitioner (GP) in the prevention of suicidal behaviour and in the aftercare of DSH patients is also important. AIM: To examine the nature and timing of GP contacts with DSH patients before and after an episode of DSH, and patients' satisfaction with these contacts. DESIGN OF STUDY: Structured interviews with patients shortly after an episode of DSH and again approximately one year later. SETTING: A representative sample of 139 DSH patients presenting to a district general hospital. METHOD: Patients were interviewed shortly after DSH and at follow-up about GP contacts, prescribed medication and psychiatric symptoms. RESULTS: At the time of DSH, 91.4% of patients were diagnosed with a psychiatric disorder (depression 69.8%), with 28% receiving treatment from psychiatric services. Two-thirds of patients had been in contact with their GP in the month before DSH, but only 13.3% reported expressing suicidal thoughts. Patients consulted their GP in the week following DSH in 40.6% of cases. Over half (57.9%) the patients discussed the reasons for their DSH at the first consultation and 69.5% reported that this was helpful. Overall, 64.3% of patients were satisfied with the follow-up consultations. CONCLUSIONS: The major role of the GP in the prevention of suicidal behaviour is in the detection and treatment of depression, and in the aftercare of DSH patients.

Adolescent↗

PubMed2001

Effects of legislation restricting pack sizes of paracetamol and salicylate on self poisoning in the United Kingdom: before and after study.

OBJECTIVE: To evaluate the effects on suicidal behaviour of legislation limiting the size of packs of paracetamol and salicylates sold over the counter. DESIGN: Before and after study. SETTING: UK population, with detailed monitoring of data from five liver units and seven general hospitals, between September 1996 and September 1999. SUBJECTS: People who died by suicidal or accidental overdose with paracetamol or salicylates or who died of undetermined causes; patients admitted to liver units with hepatic paracetamol poisoning; patients presenting to general hospitals with self poisoning after taking paracetamol or salicylates. MAIN OUTCOME MEASURES: Mortality from paracetamol or salicylate overdose; numbers of patients referred to liver units or listed for liver transplant; numbers of transplantations; numbers of overdoses and tablets taken; blood concentrations of the drugs; prothrombin times; sales to pharmacies and other outlets of paracetamol and salicylates. RESULTS: Numbers of tablets per pack of paracetamol and salicylates decreased markedly in the year after the change in legislation on 16 September 1998. The annual number of deaths from paracetamol poisoning decreased by 21% (95% confidence interval 5% to 34%) and the number from salicylates decreased by 48% (11% to 70%). Liver transplant rates after paracetamol poisoning decreased by 66% (55% to 74%). The rate of non-fatal self poisoning with paracetamol in any form decreased by 11% (5% to 16%), mainly because of a 15% (8% to 21%) reduction in overdoses of paracetamol in non-compound form. The average number of tablets taken in paracetamol overdoses decreased by 7% (0% to 12%), and the proportion involving >32 tablets decreased by 17% (4% to 28%). The average number of tablets taken in salicylate overdoses did not decrease, but 34% fewer (2% to 56%) salicylate overdoses involved >32 tablets. After the legislation mean blood concentrations of salicylates after overdose decreased, as did prothrombin times; mean blood concentrations of paracetamol did not change. CONCLUSION: Legislation restricting pack sizes of paracetamol and salicylates in the United Kingdom has had substantial beneficial effects on mortality and morbidity associated with self poisoning using these drugs.

Acetaminophen↗

PubMed2001

Lithium for maintenance treatment of mood disorders.

BACKGROUND: Mood disorders are common, disabling and tend to be recurrent. They carry a high risk of suicide. Maintenance treatment, aimed at the prevention of relapse, is therefore of vital importance. Lithium has been used for some years as the mainstay of maintenance treatment in bipolar affective disorder, and to a lesser extent in unipolar disorder. However, the efficacy and effectiveness of prophylactic lithium therapy has been disputed. Low suicide rates in lithium-treated patients have led to claims that lithium has a specific anti-suicidal effect. If so, this is of considerable importance as treatments for mental disorders in general have not been shown convincingly to be effective in suicide prevention. OBJECTIVES: 1. To investigate the efficacy of lithium treatment in the prevention of relapse in recurrent mood disorders. 2. To examine the effect of lithium treatment on consumers' general health and social functioning, its acceptability to consumers, and the side-effects of treatment. 3. To investigate the hypothesis that lithium has a specific effect in reducing the incidence of suicide and deliberate self-harm in persons with mood disorders. SEARCH STRATEGY: The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) and The Cochrane Controlled Clinical Trials Register (CCTR) were searched. Reference lists of relevant papers and major text books of mood disorder were examined. Authors, other experts in the field and pharmaceutical companies were contacted for knowledge of suitable trials, published or unpublished. Specialist journals concerning lithium were hand searched. SELECTION CRITERIA: Randomised controlled trials comparing lithium with placebo, where the stated intent of treatment was maintenance or prophylaxis. Participants were males and females of all ages with diagnoses of mood disorder. Discontinuation studies (in which all participants had been stable on lithium for some time before being randomised to either continued lithium treatment or placebo substitution) were excluded. DATA COLLECTION AND ANALYSIS: Data were extracted from the original reports independently by two reviewers. The main outcomes studied were related to the objectives stated above. Data were analysed for all diagnoses of mood disorder and for bipolar and unipolar disorder separately. Data were analysed using Review Manager version 4.0. MAIN RESULTS: Nine studies were included in the review, reporting on 825 participants randomly allocated to lithium or placebo. Lithium was found to be more effective than placebo in preventing relapse in mood disorder overall, and in bipolar disorder. The most consistent effect was found in bipolar disorder (random effects OR 0.29; 95% CI 0.09 to 0.93 ). In unipolar disorder, the direction of effect was in favour of lithium, but the result (when heterogeneity between studies was allowed for) did not reach statistical significance. Considerable heterogeneity was found between studies in all groups of patients. The direction of effect was the same in all studies; no study found a negative effect for lithium. Heterogeneity may have been due to differences in selection of participants, and to differing exposures to lithium in the pre-study phase resulting in variable influence of a discontinuation effect. There was little reported data on overall health and social functioning of participants under the different treatment conditions, or on the participants' own views of their treatment. Descriptive analysis showed that assessments of general health and social functioning generally favoured lithium. Small absolute numbers of deaths and suicides, and the absence of data on non-fatal suicidal behaviours, made it impossible to draw meaningful conclusions about the place of lithium therapy in suicide prevention. REVIEWER'S CONCLUSIONS: This systematic review indicates that lithium is an efficacious maintenance treatment for bipolar disorder. In unipolar disorder the evidence of efficacy is less robust. This review does not cover the relative efficacy of lithium compared with other maintenance treatments, which is at present unclear. There is no definitive evidence from this review as to whether or not lithium has an anti-suicidal effect. Systematic reviews and large scale randomised studies comparing lithium with other maintenance treatments (e.g. anti-convulsants, antidepressants) are necessary. Outcomes relating to death and suicidal behaviour should be included in all future maintenance studies of mood disorder.

Antimanic Agents↗

PubMed2001

Substances used in deliberate self-poisoning 1985-1997: trends and associations with age, gender, repetition and suicide intent.

BACKGROUND: Rates of deliberate self-poisoning have increased in recent years. While over-the-counter availability and prescribing patterns may influence trends in substances used in overdose, these may also be related to clinical characteristics of patients. We investigate trends in substances used for self-poisoning and the influence of age, gender, suicidal intent and repetition status on the substances used. METHOD: Data collected by the Oxford Monitoring System for Attempted Suicide were used to review trends and patterns of self-poisoning between 1985 and 1997. RESULTS: There were substantial increases in self-poisoning with paracetamol and antidepressants. While the increase in antidepressant self-poisoning closely paralleled local prescribing figures during 1995-97, SSRI antidepressant overdoses occurred somewhat more often than expected compared with tricyclic overdoses. Paracetamol overdoses were more common in first-timers and young people, whereas overdoses of antidepressants and tranquillizers were more common in repeaters and older people. Self-poisoning with gas and non-ingestible poisons was associated with high suicidal intent. CONCLUSIONS: There have been marked changes in the substances used for self-poisoning, which seem primarily to reflect availability, as do the influences of age and repeater status on choice of substances used. Degree of suicidal intent may also influence choice of method of self-poisoning.

Acetaminophen↗

PubMed2001

The efficacy of problem-solving treatments after deliberate self-harm: meta-analysis of randomized controlled trials with respect to depression, hopelessness and improvement in problems.

BACKGROUND: Brief problem-solving therapy is regarded as a pragmatic treatment for deliberate self-harm (DSH) patients. A recent meta-analysis of randomized controlled trials (RCTs) evaluating this approach indicated a trend towards reduced repetition of DSH but the pooled odds ratio was not statistically significant. We have now examined other important outcomes using this procedure, namely depression, hopelessness and improvement in problems. METHOD: Six trials in which problem-solving therapy was compared with control treatment were identified from an extensive literature review of RCTs of treatments for DSH patients. Data concerning depression, hopelessness and improvement in problems were extracted. Where relevant statistical data (e.g. standard deviations) were missing these were imputed using various statistical methods. Results were pooled using meta-analytical procedures. RESULTS: At follow-up, patients who were offered problem-solving therapy had significantly greater improvement in scores for depression (standardized mean difference = -0.36; 95% CI -0.61 to -0.11) and hopelessness (weighted mean difference =-3.2; 95% CI -4.0 to -2.41), and significantly more reported improvement in their problems (odds ratio = 2.31; 95% CI 1.29 to 4.13), than patients who were in the control treatment groups. CONCLUSIONS: Problem-solving therapy for DSH patients appears to produce better results than control treatment with regard to improvement in depression, hopelessness and problems. It is desirable that this finding is confirmed in a large trial, which will also allow adequate testing of the impact of this treatment on repetition of DSH.

Cognitive Behavioral Therapy↗

PubMed2001

Deliberate self-harm patients with alcohol disorders: characteristics, treatment, and outcome.

Deliberate self-harm (DSH) patients with alcohol problems present a considerable challenge for clinical services. In a study of a sample of 150 DSH patients who were representative of all such patients seen at a general hospital during the study period, 40 patients with an ICD-10 diagnosis of alcohol dependence or harmful use of alcohol were compared with the remainder of the sample. The treatment of the patients with alcohol disorders before and after the episode of DSH and the outcome 12-20 months later were also investigated. Compared with other DSH patients, those with an alcohol diagnosis were older and more often male, living alone, unemployed, sick, disabled, or with a past history of DSH. They also had higher scores on measures of anger, aggression, and impulsivity. Comorbid psychiatric disorder was present in 37 (92.5%) patients, this being depression in three-quarters of those cases. Fourteen (35.0%) patients were receiving treatment from the psychiatric services prior to DSH, and 33 (82.5%) were subsequently offered treatment. Of the patients who were followed up, 37.9% remained in contact with psychiatric services, 55.2% showed poor compliance with treatment and 44.8% reported a further episode of DSH. All patients presenting after DSH need to be carefully screened for alcohol disorders and for comorbid psychiatric diagnoses. Treatment of DSH patients with alcohol disorders should include the treatment of any comorbid depressive illness.

Adolescent↗

PubMed2001

Psychiatric and personality disorders in deliberate self-harm patients.

BACKGROUND: Previous UK studies have reported much lower rates of psychiatric and personality disorder in those who attempt suicide than in those who die by suicide. AIMS: To determine the nature and prevalence of psychiatric and personality disorders in deliberate self-harm (DSH) patients. METHOD: A representative sample of 150 DSH patients who presented to a general hospital were assessed using a structured clinical interview and a standardised instrument. Follow-up interviews were completed for 118 patients approximately 12-16 months later. RESULTS: ICD-10 psychiatric disorders were diagnosed in 138 patients (92.0%), with comorbidity of psychiatric disorders in 46.7%. The most common diagnosis was affective disorder (72.0%). Personality disorder was identified in 45.9% of patients interviewed at follow-up. Comorbidity of psychiatric and personality disorder was present in 44.1%. CONCLUSIONS: Psychiatric and personality disorders, and their comorbidity, are common in DSH patients. This has important implications for assessment and management.

Adolescent↗

PubMed2001

Psychosocial and pharmacological treatment of patients following deliberate self-harm: the methodological issues involved in evaluating effectiveness.

Development of effective treatments for patients following deliberate self-harm (self-poisoning or self-injury) is a very important element in suicide prevention. The randomized controlled trial (RCT) is the mainstay of evaluation of treatments. In a systematic review of the literature, the effectiveness of treatments based on RCTs was examined and the quality of the RCTs was assessed. Twenty trials were identified, and where possible, these were grouped on the basis of similarities among the types of treatment. In this paper, we examine the methodological aspects of the trials and consider what may be learned that will assist in the design of future studies in this field. The methodological quality of the trials was reasonable, but most trials included too few participants to detect clinically important differences in rates of repeated self-harm. In planning future trials, the following major issues should be addressed: investigators should perform power calculations to determine the number of subjects necessary to detect clinically important effects, provide information on method of randomization and interventions, use standard measures of outcome, and focus on homogeneous subgroups of patients. Improving the methodology of future studies in this field will be essential if sound evidence is to be obtained which can inform effective service provision for deliberate self-harm patients.

Humans↗

PubMed2000

Psychosocial versus pharmacological treatments for deliberate self harm.

OBJECTIVES: To identify and synthesise the findings from all randomised controlled trials that have examined the effectiveness of treatments of patients who have deliberately harmed themselves. SEARCH STRATEGY: Electronic databases screened: MEDLINE (from 1966-February 1999); PsycLit (from 1974-March 1999); Embase (from 1980-January 1999); The Cochrane Controlled Trials Register (CCTR) No.1 1999. Ten journals in the field of psychiatry and psychology were hand searched for the first version of this review. We have updated the hand search of three specialist journals in the field of suicidal research until the end of 1998. Reference lists of papers were checked and trialists contacted. SELECTION CRITERIA: All RCTs of psychosocial and/or psychopharmacological treatment versus standard or less intensive types of aftercare for patients who shortly before entering a study engaged in any type of deliberately initiated self-poisoning or self-injury, both of which are generally subsumed under the term deliberate self-harm. DATA COLLECTION AND ANALYSIS: Data were extracted from the original reports independently by two reviewers. Studies were categorized according to type of treatment. The outcome measure used to assess the efficacy of treatment interventions for deliberate self-harm was the rate of repeated suicidal behaviour. We have been unable to examine other outcome measures as originally planned (e.g. compliance with treatment, depression, hopelessness, suicidal ideation/thoughts, change in problems/problem resolution). MAIN RESULTS: A total of 23 trials were identified in which repetition of deliberate self-harm was reported as an outcome variable. The trials were classified into 11 categories. The summary odds ratio indicated a trend towards reduced repetition of deliberate self-harm for problem-solving therapy compared with standard aftercare (0.70; 0.45 to 1.11) and for provision of an emergency contact card in addition to standard care compared with standard aftercare alone (0.45; 0.19 to 1.07). The summary odds ratio for trials of intensive aftercare plus outreach compared with standard aftercare was 0.83 (0.61 to 1.14), and for antidepressant treatment compared with placebo was 0.83 (0. 47 to 1.48). The remainder of the comparisons were in single small trials. Significantly reduced rates of further self-harm were observed for depot flupenthixol vs. placebo in multiple repeaters (0. 09; 0.02 to 0.50), and for dialectical behaviour therapy vs. standard aftercare (0.24; 0.06 to 0.93). REVIEWER'S CONCLUSIONS: There still remains considerable uncertainty about which forms of psychosocial and physical treatments of self-harm patients are most effective, inclusion of insufficient numbers of patients in trials being the main limiting factor. There is a need for larger trials of treatments associated with trends towards reduced rates of repetition of deliberate self-harm. The results of small single trials which have been associated with statistically significant reductions in repetition must be interpreted with caution and it is desirable that such trials are also replicated.

Cognitive Behavioral Therapy↗

PubMed2000

Reflections on a renaissance of occupation.

At the close of the 20th century, there is a renaissance of occupation in occupational therapy and occupational science. Kielhofner (1992) offers an intraprofessional explanation that the growing interest in occupation recaptures occupational therapy's lost identity. An extraprofessional explanation is that postmodern ideas and social practices have helped to create a societal context in which a renaissance of occupation is welcome. Postmodernism raises questions and awareness of power, diversity, temporality, and situatedness in which normative ideas of occupation as paid work can be challenged. Since occupation is of primary concern to occupational therapy and occupational science, the authors reflect on postmodernism and its influence on a renaissance of occupation in these two fields. These reflections consider what such a renaissance means for occupational therapists and occupational scientists in the 21st century.

Forecasting↗

PubMed1998

Deliberate self harm: systematic review of efficacy of psychosocial and pharmacological treatments in preventing repetition.

OBJECTIVE: To identify and synthesise the findings from all randomised controlled trials that have examined the effectiveness of treatments of patients who have deliberately harmed themselves. DESIGN: Systematic review of randomised controlled trials of psychosocial and physical treatments. Studies categorised according to type of treatment. When there was more than one investigation in a particular category a summary odds ratio was estimated with the Mantel-Haenszel method. SETTING: Randomised trials available in electronic databases in 1996, in the Cochrane Controlled Trials Register in 1997, and from hand searching of journals to 1997. SUBJECTS: Patients who had deliberately harmed themselves shortly before entry into the trials with information on repetition of behaviour. The included trials comprised 2452 randomised participants with outcome data. MAIN OUTCOME MEASURE: Repetition of self harm. RESULTS: 20 trials reported repetition of self harm as an outcome variable, classified into 10 categories. Summary odds ratio (all for comparison with standard aftercare) indicated reduced repetition for problem solving therapy (0.73; 95% confidence interval 0.45 to 1.18) and for provision of an emergency contact card in addition to standard care (0.45; 0.19 to 1.07). The summary odds ratios were 0.83 (0.61 to 1.14) for trials of intensive aftercare plus outreach and 1.19 (0.53 to 2.67) for antidepressant treatment compared with placebo. Significantly reduced rates of further self harm were observed for depot flupenthixol versus placebo in multiple repeaters (0.09; 0.02 to 0.50) and for dialectical behaviour therapy versus standard aftercare (0.24; 0.06 to 0.93). CONCLUSION: There remains considerable uncertainty about which forms of psychosocial and physical treatments of patients who harm themselves are most effective. Further larger trials of treatments are needed.

Aftercare↗

PubMed1998

Complement activation during major surgery: the effect of extracorporeal circuits and high-dose aprotinin.

OBJECTIVE: To assess the in vivo contribution to complement activation of an extracorporeal circuit and the use of high-dose aprotinin during major surgery. DESIGN: Sequential samples were obtained from 8 patients undergoing thoracic surgery, 20 patients undergoing orthotopic liver transplantation (OLT) using venovenous bypass, and 19 patients undergoing cardiac surgery using cardiopulmonary bypass (CPB). INTERVENTION: The latter two groups were part of a randomized controlled trial of high-dose aprotinin. MEASUREMENTS: Total complement activation was measured with the hemolytic complement activity and the C3 activation-specific marker, C3d antigen. MAIN RESULTS: Complement activation did not occur during thoracic surgery. During OLT, C3d antigen levels, expressed as mean +/- standard deviation (SD), were elevated from baseline at skin closure (8.6 +/- 2.5 v 13.0 +/- 5.2 mg/L; p = 0.0082). During cardiac surgery, C3d antigen levels increased 10 minutes after the start of CPB (pre-CPB, 8.0 +/- 1.9 v 14.2 +/- 3.1 mg/L; p = 0.0001) and remained at greater than baseline values postoperatively (8.0 +/- 1.9 v 11.8 +/- 2.3 mg/L; p = 0.002). There was no difference in complement activation in those receiving high-dose aprotinin during OLT or cardiac surgery. Complement activation during cardiac surgery using extracorporeal circulation occurred to a greater extent than during OLT and thoracic surgery. Complement activation during cardiac surgery or OLT was not attenuated by the use of high-dose aprotinin.

Adolescent↗

PubMed1997

Gamma delta T cells: their immunobiology and role in malaria infections.

The status of research on gamma delta T cells is reviewed. Recent research shows that gamma delta T cells may see antigens in an immunoglobulin-like manner and that non-peptidic substance can be antigens for these cells. Considerable advances have been made in defining the immunobiology of gamma delta T cells, with evidence for sentinel, protective and immunoregulatory roles. Research on gamma delta T cells in malaria infections suggests that gamma delta T cells are mediators of protective immunity, most probably through the production of Th1 cytokines such as TNF alpha, TNF delta and IFN gamma and that excessive production of such cytokines may contribute to pathology. Our data on the features of the peripheral blood gamma delta T cells response in humans infected with Plasmodium falciparum show that there is considerable variation between individuals in the relative expansion of gamma delta T lymphocytes following primary or secondary infection. They confirm that activation of gamma delta T cells occurs during P. falciparum infection and that activated cells can persist for many weeks after treatment. The possibility that gamma delta T cells have an immunoregulatory function in malaria infections is proposed.

Cytokines↗

PubMed1996

Prevalence of abdominal aortic aneurysm in a hypertensive population.

Two studies were undertaken to estimate the prevalence of abdominal aortic aneurysm in a hypertensive population. The initial study screened hypertensive people from three local general practices. In this study 918 patients underwent ultrasound scanning of the abdominal aorta (498 men and 420 women). A total of 24 abdominal aortic aneurysms were identified; 20 in men (4%) and four in women (0.9%). Of these, 11 were > 4 cm in transverse diameter. Following this study, only hypertensive men over the age of 60 years and women over the age of 65 years were screened from a total of 29 general practices. Regular scanning sessions were held at each practice and 1328 patients attended (744 men and 584 women). A total of 43 abdominal aortic aneurysms were detected; 39 in men (5.2%) and four in women (0.7%). Hypertensive men are at increased risk of developing abdominal aortic aneurysms and should be offered an initial ultrasound scan at 60 years of age. Female hypertensives yield a much lower detection rate and screening hypertensive females would probably be an inappropriate use of available resources.

Age Distribution↗

PubMed1993

PCNA immunostaining in breast cancer.

Expression of proliferating cell nuclear antigen (PCNA) has been shown to be of prognostic value in patients with certain types of cancer. The aim of this study was to determine if the abundance of PCNA is inversely correlated with survival of patients with breast cancer. Paraffin blocks were available from 68 patients, all of whom had been followed clinically for at least 5 years. Sections from 20 patients showed no reactivity to PCNA and were excluded from the study because it was not possible to distinguish between true negatives and false negatives (those due to poor fixation of the original specimens). The PCNA index (the number of stained cancer cells as a percentage of the total number of cancer cells present) was calculated for the remaining 48 patients. Results were analysed by Wilcoxon's rank sum test (two tailed) and Pearson's correlation coefficient. There was no statistical difference between the PCNA indices of those patients dead from their disease within 5 years of diagnosis compared with those alive and without signs of breast cancer at 5 years. There was also no correlation between PCNA index and size of the cancer, involvement of axillary lymph nodes, time to recurrence or time to death. There was, however, a significant correlation between PCNA index and histological grade (P = 0.029). It appears that PCNA staining of stored paraffin sections is of little prognostic value in patients with breast cancer.

Antibodies, Monoclonal↗

PubMed1993

1993 Muriel Driver Lecture. Occupational therapy's social vision.

Occupational therapy has tremendous, unfulfilled potential. The lecture critically analyzes that potential in light of occupational therapy's social vision. The analysis is built on emerging views of occupational therapy's core philosophy of client-centered practice using the ordinary occupations of daily life as a form of therapy. Critical analysis shows that foundational features of occupational therapy are consistent with foundational features of social justice. However, analysis also shows that occupational therapy's social vision is narrowed to comply with dominant community, managerial and medical approaches to disability and aging. Given therapists' good intentions, critical analysis is unnerving, but it provides a guide for transforming practice and developing occupational therapy's potential.

Canada↗

PubMed1993

Occupational therapy guidelines for client-centred practice: impact study findings.

The Guidelines Impact Study investigated use and usefulness of the guidelines for client-centred practice produced in the 1980's by the Department of National Health and Welfare and the Canadian Association of Occupational Therapists. This paper outlines the study, summarizes findings, and discusses implications for revising and updating the Guidelines. Qualitative interview data from key informants across Canada were incorporated into a quantitative survey of a 5% sample of CAOT members. Data reveal variable use of the Guidelines, with greatest use in acute care and rehabilitation services; and mixed interpretations of the Model of Occupational Performance, particularly 'environment' and 'spiritual component'. Recommendations include: clarification of the purpose and audience of revised Guidelines; national consultation during updating to include diverse forms of practice; and rethinking the Model of Occupational Performance as a dynamic model. Updated Guidelines should include both generic concepts and specific applications for different types of occupational therapy practice.

Attitude of Health Personnel↗

PubMed1992

Development of a sensitive peptidase assay: in search of cell associated proteases responsible for the cleavage of preproTGF alpha.

A radiometric assay has been developed for the detection of proteolytic activity capable of releasing transforming growth factor alpha (TGF alpha) from its membrane bound precursor. The assay is dependent upon the separation by thin layer chromatography of hydrolytic products of a nonapeptide substrate containing a radioactive iodinated tyrosine residue as a reporting group N-terminal to an octapeptide which is cognate to the N-terminal cleavage sequence of TGF alpha. We describe the selectivity of the peptidase assay with commercially purified proteases and with cell-associated peptidases, its exquisite sensitivity, and its applicability to defining peptidase activity, which may be responsible for the processing of the membrane-bound prepro TGF alpha. The activity of two different elastases had different profiles which thus may be of use in characterizing them. The characteristics of the intact and extracted HeLa cell assay with respect to time, cell density, and peptidase concentration are defined, as are conditions needed to remove endogenous, confounding, proteolytic activity from the serum used to support cell culture. Intact HeLa cell cultures exhibit both exo- and endo-peptidase activity at approximately equal levels in both sparse and dense monolayer culture without relationship to cell density, and at a level equal to 1-2% of total cell activity of these enzyme classes.

Amino Acid Sequence↗