Feasibility and acceptability of NIDUS-professional, a training and support intervention for homecare workers caring for clients living with dementia: a cluster-randomised feasibility trial

INTRODUCTION

In the first randomised controlled trial of a dementia training and support intervention in UK homecare agencies, we aimed to assess: acceptability of our co-designed, manualised training, delivered by non-clinical facilitators; outcome completion feasibility; and costs for a future trial.

METHODS

This cluster-randomised (2:1) single-blind, feasibility trial involved English homecare agencies. Intervention arm agency staff were offered group videocall sessions: 6 over 3 months, then monthly for 3 months (NIDUS-professional). Family carers (henceforth carers) and clients with dementia (dyads) were offered six to eight complementary, individual intervention sessions (NIDUS-Family). We collected potential trial measures as secondary outcomes remotely at baseline and 6 months: HCW (homecare worker) Work-related Strain Inventory (WRSI), Sense of Competence (SoC); proxy-rated Quality of Life (QOL), Disability Assessment for Dementia scale (DAD), Neuropsychiatric Inventory (NPI) and Homecare Satisfaction (HCS).

RESULTS

From December 2021 to September 2022, we met agency (4 intervention, 2 control) and HCWs (n = 62) recruitment targets and recruited 16 carers and 16/60 planned clients. We met a priori progression criteria for adherence (≥4/6 sessions: 29/44 [65.9%,95% confidence interval (CI): 50.1,79.5]), HCW or carer proxy-outcome completion (15/16 (93.8% [69.8,99.8]) and proceeding with adaptation for HCWs outcome completion (46/63 (73.0% [CI: 60.3,83.4]). Delivery of NIDUS-Professional costs was £6,423 (£137 per eligible client). WRSI scores decreased and SoC increased at follow-up, with no significant between-group differences. For intervention arm proxy-rated outcomes, carer-rated QOL increased, HCW-rated was unchanged; carer and HCW-rated NPI decreased; DAD decreased (greater disability) and HCS was unchanged.

CONCLUSION

A pragmatic trial is warranted; we will consider using aggregated, agency-level client outcomes, including neuropsychiatric symptoms.

Feasibility and acceptability of NIDUS-Professional, a training and support intervention for homecare workers caring for clients living with dementia: a cluster-randomised feasibility trial protocol

INTRODUCTION

Most people living with dementia want to remain living in their own homes, and are supported to do so by family carers and homecare workers. There are concerns that homecare is often unable to meet the needs of this client group, with limited evidence regarding effective interventions to improve it for people living with dementia. We have developed a training and support programme for homecare workers (NIDUS-Professional) to be delivered alongside support sessions for people living with dementia and their family carers (NIDUS-Family). We aim to assess (1) its acceptability among homecare workers and employing agencies, and (2) the feasibility of homecare workers, people living with dementia and their family carers completing the outcomes of intervention in a future randomised controlled trial.

METHODS AND ANALYSIS

This is a cluster-randomised (2:1) single-blind, multisite feasibility trial. We aim to recruit 60-90 homecare workers, 30-60 clients living with dementia and their family carers through 6-9 English homecare agencies. In the intervention arm, homecare staff will be offered six group sessions on video call over three months, followed by monthly group sessions over the subsequent three-month period. Outcome measures will be collected at baseline and at six months.

ETHICS AND DISSEMINATION

The study received ethical approval on 7 January 2020 from the Camden & King's Cross Research Ethics Committee. Study reference: 19/LO/1667. Findings will be disseminated through a peer-reviewed journal, conference presentation and blog to research and clinical audiences; we will attend forums to present findings to participating homecare agencies and their clients.

TRIAL REGISTRATION NUMBER

ISRCTN15757555.

Time to reflect is a rare and valued opportunity; a pilot of the NIDUS-professional dementia training intervention for homecare workers during the Covid-19 pandemic

Most people living with dementia want to continue living in their own home for as long as possible and many rely on support from homecare services to do so. There are concerns that homecare often fails to meet the needs of clients with dementia, but there is limited evidence regarding effective interventions to improve its delivery for this client group. We aimed to assess whether a co-designed, 6-session dementia training intervention for homecare workers (NIDUS-professional) was acceptable and feasible. Facilitated training sessions were delivered over 3 months, followed by 3, monthly implementation meetings to embed changes in practice. Two trained and supervised facilitators without clinical qualifications delivered the intervention via group video-calls during Oct 2020-March 2021 to a group of seven homecare workers from one agency in England. Participants provided qualitative feedback 3- and 6-months post intervention. Qualitative interview data and facilitator notes were integrated in a thematic analysis. Adherence to the intervention and fidelity of delivery were high, indicating that it was acceptable and feasible to deliver in practice. Thirty of a possible 42 (71.4%) group sessions were attended. In our thematic analysis we report one over-arching theme: 'Having time and space to reflect is a rare opportunity'. Within this we identified four subthemes (Having time to reflect is a rare opportunity; Reflecting with peers enhances learning; Reflection and perspective taking can improve care; Recognising skills and building confidence) through which we explored how participants valued the intervention to discuss their work and learn new skills. Attendance was lower for the implementation sessions, perhaps reflecting participants' lack of clarity about their purpose. We used our findings to consider how we can maintain positive impacts of the manualised sessions, so that these are translated into tangible, scalable benefits for people living with dementia and the homecare workforce. A randomised feasibility trial is underway.

Mortality, morbidity, and cardiovascular risk factor outcomes from cardiac rehabilitation, in ethnic minorities: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Abstract

Background

Cardiac rehabilitation (CR) is a secondary prevention intervention for coronary heart disease that has well-established efficacy in reducing mortality, morbidity, and cardiovascular risk factors. However, outcomes from CR are known to differ between population groups, with ethnic minorities reported to have health outcome disparities. However, there is no synthesis of these CR outcomes for ethnic minority populations.

Purpose

The main purpose of this study was to evaluate the impact of CR on rates of mortality, morbidity, and important cardiovascular risk factor outcomes including exercise performance, exercise capacity, low-density lipoproteins, cholesterol levels, body mass index, weight, waist circumference and systolic blood pressure, within ethnic minority groups.

Methods

Four electronic databases (Medline, EMBASE, CINAHL, Scopus) were searched from February to September 2021, for studies that reported CR outcomes of ethnic minorities. Potential papers were independently screened by two reviewers, and discrepancies were resolved by a third reviewer. Data was extracted from the studies using an electronic data extraction form. Meta-analyses for eligible studies were performed using Revman 5.4. Risk of bias were assessed using the Cochrane Tool.

Results

Across 13 studies (n = 132,109 participants), the 10,494 participants of ethnic minority groups achieved significant improvements in mortality, morbidity, and most cardiovascular risk factor outcomes including exercise performance, exercise capacity, body mass index, waist circumference, and systolic blood pressure. However, while ethnic minority groups achieved equivalent outcomes from CR for exercise performance and low-density lipoproteins, some outcomes were worse (exercise capacity, body mass index, waist circumference, systolic blood pressure). In addition, minority participants had greater reductions in cholesterol levels.

Conclusion

Ethnic minority groups achieve important improvements in mortality, morbidity, and cardiovascular risk factor outcomes from CR, although to a lesser extent than majority groups. Therefore, this information can be used to support efforts to improve participation in CR and prompt changes to the delivery of CR services for ethnic minority participants.

Safety, Tolerability and Pharmacokinetics of Icapamespib, a Selective Epichaperome Inhibitor, in Healthy Adults

Background

Neurodegenerative diseases are devastating conditions that most commonly affect individuals 65 years and older. Currently there are no effective treatments or cures for neurodegenerative diseases, and therapeutics that selectively target the underlying causes of these diseases are needed. Epichaperomes play a major role in the maintenance and progression of neuronal pathology. Inhibiting epichaperomes induces degradation of disease associated proteins and is a promising therapeutic approach to treat neurodegenerative diseases, in particular Alzheimer’s Disease and amyotrophic lateral sclerosis.

Objectives

This Phase 1 clinical study evaluated the safety, tolerability, pharmacokinetics, and bioavailability of icapamespib, a purine scaffold inhibitor of epichaperomes that is specific to epichaperomes, in healthy subjects.

Design

Double-blind, placebo-controlled dose escalating single ascending dose and multiple ascending doses and an unblinded two-period cross-over bioavailability study design.

Setting

Single site in the United States.

Participants

Healthy men or women of 18 to 60 years of age, inclusive, for Part 1 (single ascending dose), ≥ 60 years of age for Part 2 (multiple ascending dose), or 18 to 49 years of age for Part 3 (bioavailability).

Treatment

In the single ascending dose group, oral single doses (10, 20, and 30 mg icapamespib or placebo) were administered to healthy non-elderly subjects. In the multiple ascending dose group, multiple doses (20 and 30 mg icapamespib once daily for 7 days or placebo) were administered to healthy elderly subjects. In the bioavailability group, the bioavailability of once daily oral icapamespib solution and tablet was assessed in healthy non elderly subjects.

Measurements

Safety was evaluated based on assessments of treatment-emergent adverse events, physical examinations, clinical laboratory tests (hematology, clinical chemistry, and urinalysis), vital signs, and 12-lead electrocardiograms. Icapamespib concentration was evaluated in plasma and cerebrospinal fluid, the latter in Part 2 (multiple ascending dose) only.

Results

Forty-eight subjects in total were randomized and assessed for tolerability, pharmacokinetics, and bioavailability parameters as follows: 24 subjects in Part 1 (single ascending dose) with PU-AD 10 mg (n = 6), 20 mg (n = 6), 30 mg (n = 6), and placebo (n = 6); 16 subjects in Part 2 (multiple ascending dose) with icapamespib 20 mg (n = 6), 30 mg (n = 6), and placebo (n = 4); and 8 subjects in Part 3 (bioavailability) crossed-over between icapamespib 30 mg (tablet) and icapamespib 30 mg (oral solution). Single doses of icapamespib up to 30 mg and multiple doses of icapamespib up to 30 mg for 7 days were generally safe and well tolerated in healthy non-elderly and elderly subjects. Treatment-emergent adverse events were mild, with headache being the most common treatment-emergent adverse event. Mean icapamespib exposure (area under the curve) was dose-proportional over the dose range tested. The median time to maximum observed plasma concentration ranged from 1.00 to 2.00 h across single ascending dose, multiple ascending dose, and bioavailability groups; icapamespib exposure was 50% higher in elderly subjects compared with non-elderly subjects but was well tolerated.

Conclusions

The study provides clinical evidence of the safety of icapamespib in healthy non elderly and elderly subjects and supports the advancement of icapamespib to Phase 2 evaluation in Alzheimer’s Disease and other neurodegenerative diseases.

Involving carers in the teaching, learning and assessment of masters students

Involving patients and carers in teaching, learning and assessment focuses the students on person-centred care by providing the opportunity to listen to, and reflect on, the perspective of patient and/or carer and also allows the students the opportunity to work in partnership with them to effect meaningful change. This paper presents an example at Teesside University where two informal carers have been involved as partners in the programme team of The Master of Arts in Advancing Practice over the past four years. In year two of the programme, the student is required to work within their organisation and governance policies to identify, implement and evaluate a practice development change project. Involving carers at critical points throughout the year has enriched, supported and challenged the students' learning. Evaluation has highlighted the role that carers can play in bringing a new dimension to the students' learning experience. The authors believe that direct involvement of this kind has much potential for other programmes in improving health and social care education which, in turn, will improve health and social care services.

Meeting complex health needs in prisons

The vast majority of prisoners have several health needs which combine at different levels of severity. This complexity of needs often amalgamates to include mental and physical illnesses, homelessness, unemployment, and drug and alcohol addictions. 'Complexity' can serve as an umbrella term for a number of health and social justice agendas, including public health, primary and secondary care, and social care, and must be fully understood to meet the 'complex needs imperative' that exists in all prisons.

[The sainsbury centre for mental health: forensic mental health services in England and wales]

The Sainsbury Centre for Mental Health (SCMH) is a charity founded in 1985 by Gatsby Charitable Foundation. The SCMH works to improve the quality of life for people with mental health problems by influencing policy and practice in mental health and related services. Working to improve the quality of mental health care for people in prison is one of SCMH main work theme. This paper describes some epidemiological aspects of mental health situation of prisoners in England and Wales and the available forensic facilities to manage this kind of patients in prison.

The impact of early dementia on outdoor life

This article reports the voices of 22 people with early to moderate dementia and their carers about the use of the outdoor environment. Analysis of semi-structured interviews demonstrates that people with early dementia value the outdoor environment for reasons such as exercise, fresh air, emotional well-being, the opportunity for informal encounters with neighbours and friends and the appreciation of the countryside. Conversely, not being able to go out was associated with feelings of depression. Carers reported that the impact of dementia was to decrease the frequency of outdoor activity and to limit the areas visited to those that were the most familiar. Maintaining outdoor activity is likely to be an effective measure in extending the period of good quality living and might decrease the period when intensive services are required. It should therefore be considered in planning for both residential care and community living in the future.

Costs of occupational therapy in residential homes and its impact on service use

The Care Home Activity Project was a feasibility study examining the effect of occupational therapy on levels of depression and quality of life of residents in care homes. This paper describes the costs of the one year occupational therapy intervention, the use and cost of services received by the residents both before and after the intervention and compares these with the services received by a control group over the same period. Eight homes in northern England were included in the study with four homes receiving the services of a full-time occupational therapist, the remaining four acting as the control group. Services received by residents in both groups were recorded at the beginning and end of the one year study. The cost of the occupational therapy intervention was computed from published unit costs with adjustments for travel, equipment costs and methods of working. There was a significant increase in the likelihood of using social services in the intervention homes. This could be explained by previously unrecognised needs being revealed by the therapists. There may have been a reduction in health costs in the intervention group. At 2005 levels, the net cost of providing the occupational therapy service was pounds 16 (E 23) per resident per week. This study demonstrates that occupational therapy is feasible in residential homes at modest cost. It may uncover unmet needs for some services. Future studies should match groups for hospital use at baseline.

The care home activity project: does introducing an occupational therapy programme reduce depression in care homes?

The primary aim of the study was to test the hypothesis that depression severity in care homes for older people would be reduced by an occupational therapy programme. This was a feasibility study for a cluster randomised controlled trial and involved four intervention and four control homes in northern England. In each intervention home a registered occupational therapist worked full-time for one year delivering an individualised programme to participants. Pre- and post-intervention data for the Geriatric Mental State-Depression Scale (primary outcome measure) were obtained for 143 participants. Secondary outcomes included dependency and quality of life. No significant intervention effects were found in any of the quantitative outcome measures, though qualitative interviews showed the intervention was valued by many participants, staff and relatives. Therapist ratings and qualitative interviews suggested that the intervention was beneficial to some participants but no distinctive characteristics were found that might enable prediction of likely benefit on initial assessment. This exploratory study provides no evidence that this intervention produced benefits in terms of depression, dependency or quality of life. Lack of prior power calculations means these are not definitive findings; but numbers were sufficient to perform the required analyses and data did not suggest effects that would have reached statistical significance with a larger sample. This study highlights issues for consideration in providing such services in care homes.

Esomeprazole 20 mg on-demand is more acceptable to patients than continuous lansoprazole 15 mg in the long-term maintenance of endoscopy-negative gastro-oesophageal reflux patients: the COMMAND Study

BACKGROUND

Symptom relief, through adherence to appropriate maintenance therapy, is the sole objective of treatment for patients with endoscopy-negative gastro-oesophageal reflux disease.

AIM

To compare the efficacy of 'on-demand' treatment with esomeprazole 20 mg vs. continuous treatment with lansoprazole 15 mg daily in patients with endoscopy-negative gastro-oesophageal reflux disease.

METHODS

Endoscopy-negative gastro-oesophageal reflux disease patients who achieved complete resolution of heartburn after short-term (2-4 weeks) treatment with esomeprazole 20 mg (n = 774) were randomized to receive either esomeprazole 20 mg on-demand (n =311) or lansoprazole 15 mg continuous daily treatment (n = 311) for 6 months.

RESULTS

Significantly more patients were willing to continue taking esomeprazole on-demand than lansoprazole continuous therapy after 6 months (93% vs. 88%; P = 0.02). This superior outcome was achieved despite patients on esomeprazole requiring medication only 38% as often as those on lansoprazole, leading to direct cost savings of more than one-third (36%). Furthermore, patients receiving esomeprazole 20 mg on-demand were more satisfied with their treatment after 1 month compared with patients taking lansoprazole 15 mg continuously.

CONCLUSIONS

In patients with endoscopy-negative gastro-oesophageal reflux disease, esomeprazole 20 mg on-demand is more acceptable to patients and is an economically more effective treatment than lansoprazole 15 mg continuously.

Early asthma control and maintenance with eformoterol following reduction of inhaled corticosteroid dose

BACKGROUND

Previous studies have indicated the benefits of adding long acting beta(2) agonists to inhaled corticosteroids in the maintenance treatment of moderate to severe asthma. The effects of adding eformoterol to corticosteroids on asthma control and exacerbations in patients with mild to moderate asthma were studied.

METHODS

After a run in period of 7-14 days on existing medication, 663 symptomatic patients were randomised to receive budesonide Turbohaler 400 microg twice daily together with either eformoterol Turbohaler 9 micro g (delivered dose) or placebo twice daily. After 4 weeks patients whose asthma was well controlled (n=505) were re-randomised to receive budesonide 400 microg daily and either eformoterol 9 micro g or placebo twice daily for a further 6 months.

RESULTS

Patients receiving eformoterol achieved asthma control 10 days sooner than those receiving budesonide alone, and improvements in lung function, symptoms, quality of life, and relief beta(2) agonist use were significantly greater with eformoterol. During the 6 month follow up the frequency of mild exacerbations was significantly lower in the eformoterol group than in those receiving budesonide alone (7.2 versus 10.5 per patient, 95% confidence interval for ratio 0.49 to 0.96, p=0.03). The time to first day of poorly controlled asthma was 97 days in the eformoterol group compared with 42 days in the placebo group (p=0.003).

CONCLUSIONS

Adding eformoterol to a low or moderate dose of budesonide in mild asthma resulted in faster and more effective control than treatment with budesonide alone. Eformoterol allowed the corticosteroid dose to be reduced while also decreasing the rate of mild exacerbations compared with budesonide alone. These data suggest a therapeutic advantage of adding eformoterol to inhaled corticosteroids in patients with mild to moderate asthma.

Development of an ELISA for bovine IL-10

The objective of the study was to develop an assay for bovine IL-10 that could be applied to analyses of immune responses and advance understanding of a variety of diseases of cattle. Recombinant bovine IL-10 (rbo IL-10) was transiently expressed in Cos-7 cells and shown to inhibit the synthesis of IFN gamma by bovine cells stimulated with antigen in vitro. Mice were immunised with a plasmid containing a cDNA insert encoding rbo IL-10 and inoculated with rbo IL-10. A number of monoclonal antibodies (mAb) were generated that reacted with rbo IL-10 in an ELISA. Some of these mAb neutralised the ability of rbo IL-10 to inhibit IFN gamma synthesis by antigen-stimulated bovine cells. A pair of mAb was identified that together could be used to detect both recombinant and natural bovine IL-10 present in supernatant of PBMC stimulated with ConA. A luminescent detection method was applied to the ELISA making it more sensitive. Using this method native IL-10 was detected in supernatants of PBMC, diluted blood and undiluted blood from cattle immunised with Mycobacterium bovis BCG or ovalbumin and incubated in vitro with antigen indicating the applicability of the assay to a number of in vitro culture systems.

Young adults' immediate and delayed reactions to simulated marital conflicts: implications for intergenerational patterns of violence in intimate relationships

This study investigated the thoughts and feelings that young adults from violent (VPA) and nonviolent (NPA) interparental-conflict backgrounds reported while listening to simulated marital conflicts and after a delay for reflection. While listening to conflicts, VPAs were more likely than NPAs to predict negative outcomes and to place blame. No between-groups differences regarding negative outcomes emerged after a delay. VPAs also reported perpetrating and experiencing more aggressive conflict in their dating relationships. Post hoc probes revealed that the negative-outcome-prediction and blaming variables played no significant mediating role in participants' intergenerational patterns of intimate-relationship aggression; however, methodological limitations likely compromised the statistical power for examining this mediational model. Results are discussed in light of research regarding intergenerational patterns of violence within families.

Management of older patients with hypertension in primary care: improvement on the rule of halves

OBJECTIVES

the benefits of treatment of hypertension in older people are well-established but implementation of this knowledge may be sub-optimal. We have determined recent primary care management of older people with hypertension.

METHODS

we examined health records (n = 6986) of a 1 in 7 sample of patients aged 65-80 years from a random sample of practices (n = 51) in the former Northern Region of the UK, stratified by health authority, for the previous 6 years. We recorded documented risk factors, diagnosis of hypertension, three most recent blood pressure readings, current drug therapy and previous blood pressure lowering therapy, and presence of coexistent pathology.

RESULTS

blood pressure was defined as hypertensive (> or = 160/> or = 90 mmHg; one or both values above these limits), normotensive or undetermined using a validated algorithm. In 30% of patients, blood pressure status was undetermined. Thirty-five percent of subjects were found to be hypertensive. Of these, 70% were receiving antihypertensive treatment but only 30% of treated patients had controlled (< 150 and 90 mmHg) and 13% well controlled (< 140 and 85 mmHg) blood pressure. In all, 14% of older hypertensive patients were detected, treated and had their hypertension controlled. There were significant differences between practices in the proportion of hypertensive patients treated (P < 0.001) and in the proportion of hypertensive patients whose blood pressure was controlled (P < 0.01).

CONCLUSIONS

treatment of hypertension in older people in primary care has improved in terms of detection and treatment but in only one-third of patients is high blood pressure controlled. There remain important opportunities for prevention of stroke and myocardial infarction in this age group through achieving improved blood pressure control.

Peroxidation of proteins before lipids in U937 cells exposed to peroxyl radicals

This study provides the first report of the formation of protein hydroperoxides in cells attacked by reactive oxygen species. U937 cells exposed to peroxyl radicals generated by the thermal decomposition of a water-soluble azo compound gradually accumulated hydroperoxide (-OOH) groups. In an incubation for 22 h, 1.2 mM peroxyl radicals was generated and each cell acquired 1.5x10(8) -OOH groups. These groups were located on the cell proteins; no lipid peroxidation was detected. The extent of protein peroxidation was proportional to the rate of generation of the peroxyl radicals. There was no lag period before the onset of peroxidation, indicating that cell antioxidants could not protect the proteins. The half-life of protein hydroperoxides in cell suspensions was approx. 4 h at 37 degrees C. Our results suggest that protein hydroperoxides might have a significant role as intermediates in the development of biological damage initiated by reactive oxygen species.

Systems change resulting from HIV/AIDS education and training. A cross-cutting evaluation of nine innovative projects

An evaluation of nine diverse HIV/AIDS training programs assessed the degree to which the programs produced changes in the ways that health care systems deliver HIV/AIDS care. Participants were interviewed an average of 8 months following completion of training and asked for specific examples of a resulting change in their health care system. More than half of the trainees gave at least one example of a systems change. The examples included the way patient referrals are made, the manner in which agency collaborations are organized, and the way care is delivered.

Are postal questionnaire surveys of reported activity valid? An exploration using general practitioner management of hypertension in older people

BACKGROUND

Postal questionnaire surveys are commonly used in general practice and often ask about self-reported activity. The validity of this approach is unknown.

AIM

To explore the criterion validity of questions asking about self-reported activity in a self-completion questionnaire.

METHOD

A comparison was made between (a) the self-reported actions of all general practitioner (GP) principals in 51 general practices randomly selected within the nine family health services authorities of the former northern regional health authority, and (b) the contents of the medical records (case notes and computerized records) of patients classified as hypertensive from a 1 in 7 random sample of all patients registered in these practices and aged between 65 and 80. Data were gathered from the GPs by self-completion postal questionnaires. Six comparisons were made for two groups of items: first, target and achieved blood pressure; secondly, patient's weight, smoking status, alcohol consumption, exercise and salt intake. The frequency with which the data items were recorded in patient records was compared with the GPs' self-reported frequency of performing the actions.

RESULTS

No relationship was found between achieved blood pressure and stated target levels. For each of the other actions, more than half of the responders reported that they usually or always performed the activity. For four of these (smoking, weight, alcohol and exercise), a significant association was noted, but the size of this varied considerably.

CONCLUSIONS

There is a variable relationship between what responders report that they do in self-completion questionnaires, and what they actually do as judged by the contents of their patients' medical records. In the absence of prior, knowledge of the validity of questions on reported activity, or of concurrent attempts to establish their validity, the questions should not be asked.

Use of differential normal pulse voltammetry for the measurement of locus coeruleus catecholaminergic metabolism in an acute anaesthetized rodent model of allodynia: effect of mexiletine

Neuropathic pain can be triggered by non-painful stimuli (e.g., light touch), a sensory abnormality termed allodynia. The acute blockade of spinal glycine receptors with intrathecal strychnine induces a reversible allodynia-like state in the rat. We describe the application of in vivo differential normal pulse voltammetry with carbon fibre micro-electrodes for monitoring the catechol oxidation current (CAOC) of the locus coeruleus (LC) in the strychnine model of allodynia. In addition, we tested the effect of mexiletine, a drug useful in the management of clinical neuropathic pain in this model. Our results show that somatosensory processing in the spinal cord of urethane-anaesthetized rats is radically altered during glycine receptor blockade such that the normally innocuous stimulus of hair deflection causes the marked activation of the LC as determined using in vivo differential normal pulse voltammetry. Mexiletine suppressed the LC and cardiovascular responses of strychnine induced allodynia. Results of this study indicate that LC CAOC, an index of LC neuronal activity: (a) is a sensitive biochemical index of strychnine-allodynia; (b) is temporally correlated with the cardiovascular and motor responses evoked by hair deflection during glycine receptor blockade; and (c) can be used to quantitate allodynia in the strychnine model.

Biosynthesis of vitamin B12: the multi-enzyme synthesis of precorrin-4 and factor IV

BACKGROUND

In order to study the biosynthesis of vitamin B12, it is necessary to produce various intermediates along the biosynthetic pathway by enzymic methods. Recently, information on the organisation of the biosynthetic pathway has permitted the selection of the set of enzymes needed to biosynthesise any specific identified intermediate. The aim of the present work was to use recombinant enzymes in reconstituted multi-enzyme systems to biosynthesise particular intermediates.

RESULTS

The products of the cobG and cobJ genes from Pseudomonas denitrificans were expressed heterologously in Escherichia coli to afford good levels of activity of the corresponding enzymes, CobG and CobJ. Aerobic incubation of precorrin-3A with the CobG enzyme alone yielded precorrin-3B. When CobJ and S-adenosyl-L-methionine were included in the incubation, the product was precorrin-4. Both precorrin 3B and precorrin-4 are known precursors of vitamin B12 and their availability has allowed new mechanistic studies of enzymic transformations.

CONCLUSIONS

Our results show that the expression of the CobG and CobJ enzymes has been successful, thus facilitating the biosynthesis of two precursors of vitamin B12. This lays the foundation for the structure determination of CobG and CobJ as well as future enzymic experiments focusing on later steps of vitamin B12 biosynthesis.

Doctors' attitudes towards the detection and treatment of hypertension in older people

Within the former northern region a questionnaire was sent to a one in two random sample of general practitioners and to consultant physicians involved in the treatment of older hypertensive patients, to determine current attitudes of doctors to the management of hypertension in older people. A total of 407 general practitioners and 125 consultant physicians (including 38 consultant geriatricians) completed the questionnaire; response rates of 58% and 73% respectively. The median (range) threshold level for intervention of an otherwise well 75-year-old patient was 180 (140-240)/100 (90-120) mm Hg for general practitioners as against current recommendations of > or = 160/90 mm Hg. Geriatricians adopted significantly lower thresholds than both general practitioners and other specialists. Target blood pressure (BP) and drug therapy were in line with British Hypertension Society recommendations. The majority of general practitioners stated that they would initiate treatment for hypertension later, be less aggressive in their treatment and accept higher levels of BP than with younger patients. Approximately half perceived compliance and lifestyle changes as problematic in older people, while approximately a third were concerned about the problems created by drug treatment and uncertainty about the practicality of treating all older hypertensive patients. A quarter expressed reluctance to initiate hypertensive treatment because of side effects and to treat isolated systolic hypertension. These stated attitudes amongst general practitioners may explain the continuing conservatism in the management of hypertension. This study found considerable variation in diagnostic threshold between doctors, which suggests that current management of hypertension in older people is likely to vary significantly.

Defining hypertension in older people from primary care case notes review

A method of defining blood pressure (BP) status from a review of primary care patient records was developed and then validated using the case notes of a general practitioner with an interest in hypertension. Data were drawn from the records of the previous 6 years of all 65 to 80-year-old patients in the practice (n = 263). Patients were then categorised as hypertensive, normotensive or 'undetermined' by using a flowchart based on the mean of the three most recent BP measurements, antihypertensive medication and comorbidities of ischaemic heart disease, myocardial infarction, angina, oedema or cardiac failure. Mean systolic BP of > or = 160 mm Hg and/or diastolic BP of > or = 90 mm Hg were used as a threshold definition of hypertension and of BP control. Disagreement between general practitioner and the notes based definition occurred in 11% of patients (5% hypertensive, 6% normotensive). Reasons for disagreement were: controlled hypertensives with comorbidities such as angina or heart failure (4%), isolated elevated readings (3%), use of antihypertensive medication for separate indications (2%), other reasons (2%). The resulting sensitivity and specificity was 86% and 88% respectively. Including the recording of a diagnosis of hypertension in the definition increased the sensitivity to 98% with specificity unchanged at 88%. Actual sensitivity of the instrument when used in other practices is likely to lie between 88% and 98% depending on the quality of the doctor's recording of the diagnosis of hypertension. These findings suggest that data from primary care case notes can provide a ready and valid means of defining cases of hypertension for studying the management of hypertension in primary care and for research purposes.

Innocuous hair deflection evokes a nociceptive-like activation of catechol oxidation in the rat locus coeruleus following intrathecal strychnine: a biochemical index of allodynia using in vivo voltammetry

Blockade of spinal glycinergic inhibition with intrathecal (i.t.) strychnine induces a reversible allodynia-like state in both conscious and lightly-anaesthetized rats. Since the locus coeruleus (LC) is activated by noxious stimuli, we determined the effect of non-noxious hair deflection (HD) on noradrenergic neuronal activity in the LC of rats treated with i.t. strychnine. Differential normal pulse voltammetry was used to measure the catechol oxidation current (CA.OC), an index of LC activity. Rats were maintained in a light plane of anaesthesia with i.v. urethane and i.t. strychnine (40 micrograms) was injected near the L1-L2 segment. HD, applied to the caudal dermatomes affected by i.t. strychnine, evoked a significant increase (max. 141 +/- 7%, n = 5, P < 0.05) in CA.OC and mean arterial pressure as compared to baseline (no strychnine). In contrast, HD had no significant effect on CA.OC or mean arterial pressure in the saline-treated rats (n = 5). Pre-treatment with i.t. MK801 (30 micrograms) significantly blocked the increase in CA.OC and mean arterial pressure evoked by HD in strychnine-treated rats. The results of this study indicated that HD, in the presence of i.t. strychnine but not saline, can evoke noradrenergic activity in the LC of lightly anaesthetized rats. This effect on the LC is: (1) comparable to that observed with noxious stimulation without i.t. strychnine; (2) segmentally localized, corresponding to the spinal site of strychnine injection; and (3) mediated by spinal NMDA receptors, consistent with the role of excitatory amino acids in sensory transmission. These data provide the first neurochemical evidence that HD, in the presence of i.t. strychnine, is a nociceptive event, supporting the use of this preparation as an experimental model of allodynia.

Mechanisms involved in the induction of human endothelial cell necrosis

The effects of the inflammatory mediators lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF) and unstimulated and activated neutrophils (PMNs) on endothelial cell (EC) necrosis were studied using the cultured human EC line (ECV-304) and human PMNs in vitro. LPS and TNF alone or their combination failed to induce EC necrosis. Activated PMNs, as evidenced by augmentations in CD11b expression and respiratory burst, induced significant EC necrosis commencing at 12 hr of coculture, which was strongly dependent on the ratio of PMN:ECs and the duration of PMN:EC coculture. In contrast, unstimulated PMNs induced no significant increases in EC necrosis. To examine the mechanisms of activated PMN-mediated EC necrosis, the oxygen radical scavengers superoxide dismutase (SOD) and catalase, as well as the protease inhibitors phenylmethylsulfonyl fluoride (PMSF), alpha 1-antitrypsin (alpha 1-AT), soybean trypsin-chymotrypsin inhibitor (TCI), and aprotinin, were studied in coculture experiments. EC necrosis induced by activated PMNs could be markedly attenuated by SOD, PMSF, alpha 1-AT, TCI, aprotinin, or their combinations. Although aprotinin enhanced respiratory burst, this agent inhibited necrosis by downregulating PMN CD11b and PMN-EC adhesion. These results demonstrate that the inflammatory mediators LPS and TNF and quiescent PMNs fail to induce EC necrosis. However, PMNs activated by inflammatory mediators can induce EC necrosis through oxidative and nonoxidative mechanisms and this process is dependent on PMN-EC adhesion.

The role of excitatory amino acids in the expression of precipitated acute and chronic clonidine withdrawal: an in vivo voltammetric study in the rat locus coeruleus

It has been previously shown that activation of excitatory amino acid (EAA) pathways contributes to hyperactivity of the locus coeruleus (LC) in antagonist precipitated opioid withdrawal. In this study, using differential normal pulse voltammetry to monitor catechol oxidation as an index of the activity of the LC, the role of EAA pathways in antagonist precipitated withdrawal after acute and chronic clonidine treatment was examined. Intracerebroventricular clonidine (10 micrograms i.c.v.) significantly reduced LC activity to 54.4 +/- 3.1% of baseline 45 minutes following the injection. Subsequent systemic injection of the selective alpha 2 receptor antagonist atipamezole (0.2 mg/kg i.v.) or yohimbine (0.5 mg/kg i.v.) resulted in a rapid reversal of the depressant effects and a significant increase in LC activity above baseline. Pretreatment with the non-selective EAA receptor antagonist gamma-D-glutamylglycine (DGG) (50 micrograms i.c.v.) attenuated the atipamezole-induced rebound response of the LC but not the reversal of clonidine action. However, both the yohimbine-induced rebound and reversal of clonidine effects were attenuated by DGG treated animals. In chronic clonidine treated animals (2, 5, 7, 10 micrograms/h i.c.v., 5 days), a challenge with atipamezole (0.2 mg/kg i.v.) produced an immediate increase in LC activity, blood pressure and heart rate. The magnitude of these responses was dependent on the dose of clonidine. The atipamezole-induced increase in LC activity and blood pressure was significantly attenuated by pretreatment with DGG (200 micrograms i.c.v.). These findings suggest that LC hyperactivity and blood pressure increases elicited during clonidine withdrawal are mediated in part by activation of EAA receptors. In this regard, the mechanisms underlying clonidine withdrawal closely resembles those underlying opioid withdrawal.

Within and between observer agreement on ultrasonic evaluation of bovine ovarian structures

A diagnostic ultrasound unit with a 5 MHz probe was used to examine ovarian structures in vitro from 32 reproductive tracts obtained at slaughter from young cows. Agreement between and within observers, and between observers and dissection results was evaluated using the kappa statistic. Agreement was high (kappa from 0.531 to 0.969) for all evaluations of corpora lutea. The sensitivity, specificity and predictive value of both positive and negative findings for presence of a corpus luteum was > 0.9. Agreement between and within observers was little better than chance for follicles measuring 4 to < 6 mm and for follicles measuring 6 to < 10 mm. However, agreement between observers and dissection results indicated that observers could detect follicles 4 to < 6 mm and 6 to < 10 mm (kappa 0.301 to 0.731 and 0.414 to 0.612, respectively). Kappa values within and between observers and between observers and dissection results for observations of follicles measuring > or = 10 mm were almost all > 0.4 indicating that large follicles can be readily detected using ultrasound. It is suggested that further validation of ultrasound methods is needed to determine whether follicles measuring < 4 mm can be accurately identified, and whether follicles can be accurately identified and monitored over a number of days. The ultrasound unit was useful for detecting the presence of corpora lutea and follicles. However, agreement between and within observers on the presence of follicles measuring < 10 mm was poor.