OA32 Minimally invasive, ultrasound-guided tissue biopsies of synovial tissue in children with Juvenile Idiopathic Arthritis for research: a feasibility study

Introduction/Background

When investigating disease mechanisms, site-specific differences in immune cell phenotype and function have highlighted the need to analyse cellular and molecular mechanisms at the tissue site directly. In adults, the ability to obtain synovial tissue biopsies using ultrasound-guided techniques, combined with advanced tissue analytics, has revolutionised our understanding of the cellular ecosystem that operates within the joint and how it contributes to disease. However, a similar approach in paediatric disease is lacking.

Description/Method

Aims: 1) To describe the protocol for undertaking minimally invasive ultrasound-guided synovial tissue biopsies in children and young people with arthritis, for the purpose of research, alongside routine clinical care. 2) To investigate whether high-quality synovial tissue can be obtained that is suitable for downstream applications including single cell profiling technologies, histology and digital spatial profiling.

Treatment-naïve children with a diagnosis of Juvenile Idiopathic Arthritis, who were being referred for a corticosteroid joint injection were recruited from two large UK Paediatric Rheumatology centres. We established a workflow pipeline for performing synovial tissue biopsies in child and young people with arthritis, using standardised procedures for biopsy and sample processing. Procedures were performed by experienced paediatric interventional radiologists with experience of joint biopsy for diagnostic purposes. Following a general anaesthetic, required as part of routine clinical care and the establishment of sterility, synovial fluid was aspirated. Needle-biopsies were undertaken from the same needle insertion site and subsequently corticosteroid was injected into the joint. Thickened synovium was graded via ultrasonography. Participating families completed questionnaires prior to and following synovial biopsy.

Discussion/Results

11 participants were recruited to the study over a nine month period, with a median age of 7 years (range 1-16 years); 91% were female. Samples obtained included core synovial biopsies, paired synovial fluid and peripheral blood. Synovial tissue fragments were processed for histology by formalin fixation and cryopreserved for downstream applications, including RNA sequencing and cell culture. Quality control indices included histological analysis to ensure the biopsied material was characteristically synovium and to grade the severity of inflammation. No significant complications were reported; however, one child had a mild haemarthrosis controlled with cold saline wash out and cold compresses.

Key learning points/Conclusion

Obtaining biopsies of synovial tissue in children with Juvenile Idiopathic Arthritis for the purpose of research, alongside clinical care is feasible. Analysis of tissue direct from the site of inflammation with single-cell RNA sequencing in children is achievable.

Developing good practice by understanding how UK medical schools address low level concerns: a survey study

In the literature, a distinction is made between low-level concerns and what is regarded as fitness to practise concerns. The General Medical Council expects all UK medical schools to have a transparent process in place about how concerns about its medical students are identified monitored and responded to. However, internationally, there is currently no well-established consensus on what is good practice in managing low-level concerns. Furthermore, currently, there is little information on how the UK medical schools vary in the processes they implement to monitor and respond to low-level concerns of their students. An online survey was developed and informed by the literature and sent to all UK medical schools to better understand their low-level concerns process. Of 39 medical schools invited, 25 participated. The data indicate variations between medical schools in the processes implemented. These variations can potentially influence the quality of the data; for example, whether there is a named person co-ordinating concerns between medical schools and placement providers. Furthermore, the data identify primary-care-based learning as offering missed opportunities where low-level concerns could be picked up. Key areas identified within the data for further work include how to quality assure that processes are equitable and how to bring more consistency to what sanctions are common and how these are decided up on.

British Thoracic Society survey of rehabilitation to support recovery of the post-COVID-19 population

OBJECTIVE

A proportion of those recovering from COVID-19 are likely to have significant and ongoing symptoms, functional impairment and psychological disturbances. There is an immediate need to develop a safe and efficient discharge process and recovery programme. Established rehabilitation programmes are well placed to deliver a programme for this group but will most likely need to be adapted for the post-COVID-19 population. The purpose of this survey was to rapidly identify the components of a post-COVID-19 rehabilitation assessment and elements of a successful rehabilitation programme that would be required to deliver a comprehensive service for those post-COVID-19 to inform service delivery.

DESIGN

A survey comprising a series of closed questions and a free-text comment box allowing for a qualitative analysis.

SETTING

Online survey.

PARTICIPANTS

Multiprofessional clinicians across specialties were invited to take part.

RESULTS

1031 participants responded from a broad range of specialties. There was overwhelming support for an early posthospital discharge recovery programme to advise patients about the management of fatigue (95% agreed/strongly agreed), breathlessness (94%) and mood disturbances (including symptoms of anxiety and depression, 92%). At the time point of 6-8 weeks, an assessment was considered important, focusing on a broad range of possible symptoms and supporting a return to work. Recommendations for the intervention described a holistic programme focusing on symptom management, return of function and return to employment. The free-text comments added depth to the survey and the need 'not to reinvent the wheel' but rather adapt well-established rehabilitation services to individually tailor needs-based care with continued learning for service development.

CONCLUSION

The responses indicate a huge interest and the urgent need to establish a programme to support and mitigate the long-term impact of COVID-19 by optimising and individualising existing rehabilitation programmes.

Notch Coordinates Periodontal Ligament Maturation through Regulating Lamin A

Tooth eruption is a continuous biological process with dynamic changes at cellular and tissue levels, particularly within the periodontal ligament (PDL). Occlusion completion is a significant physiological landmark of dentition establishment. However, the importance of the involvement of molecular networks engaging in occlusion establishment on the final PDL maturation is still largely unknown. In this study, using rat and mouse molar teeth and a human PDL cell line for RNAseq and proteomic analysis, we systematically screened the key molecular links in regulating PDL maturation before and after occlusion establishment. We discovered Notch, a key molecular pathway in regulating stem cell fate and differentiation, is a major player in the event. Intercepting the Notch pathway by deleting its key canonical transcriptional factor, RBP-Jkappa, using a conditional knockout strategy in the mice delayed PDL maturation. We also identified that Lamin A, a cell nuclear lamina member, is a unique marker of PDL maturation, and its expression is under the control of Notch signaling. Our study therefore provides a deep insight of how PDL maturation is regulated at the molecular level, and we expect the outcomes to be applied for a better understanding of the molecular regulation networks in physiological conditions such as tooth eruption and movement and also for periodontal diseases.

Neurovascular damage in experimental allergic encephalomyelitis: a target for pharmacological control

The blood-brain barrier (BBB) is composed of a continuous endothelial layer with pericytes and astrocytes in close proximity to offer homeostatic control to the neurovasculature. The human demyelinating disease multiple sclerosis and the animal counterpart experimental allergic encephalomyelitis (EAE) are characterized by enhanced permeability of the BBB facilitating oedema formation and recruitment of systemically derived inflammatory-type cells into target tissues to mediate eventual myelin loss and neuronal dysfunction. EAE is considered a useful model for examining the pathology which culminates in loss of BBB integrity and the disease is now proving valuable in assessing compounds for efficacy in limiting damage at neurovascular sites. The precise mechanisms culminating in EAE-induced BBB breakdown are unclear although several potentially disruptive mediators have been implicated and have been previously identified as potent effectors of cerebrovascular damage in non-disease related conditions of the central nervous system. The review considers evidence that common mechanisms may mediate cerebrovascular permeability changes irrespective of the initial insult and discusses therapeutic approaches for the control of BBB leakage in the demyelinating diseases.

Evaluation of the Effects of Sativex (THC BDS: CBD BDS) on Inhibition of Spasticity in a Chronic Relapsing Experimental Allergic Autoimmune Encephalomyelitis: A Model of Multiple Sclerosis

This study investigated the antispasticity potential of Sativex in mice. Chronic relapsing experimental allergic encephalomyelitis was induced in adult ABH mice resulting in hind limb spasticity development. Vehicle, Sativex, and baclofen (as a positive control) were injected intravenously and the “stiffness” of limbs assessed by the resistance force against hind limb flexion. Vehicle alone caused no significant change in spasticity. Baclofen (5 mg/kg) induced approximately a 40% peak reduction in spasticity. Sativex dose dependently reduced spasticity; 5 mg/kg THC + 5 mg/kg CBD induced approximately a 20% peak reduction; 10 mg/kg THC + 10 mg/kg CBD produced approximately a 40% peak reduction in spasticity. Sativex has the potential to reduce spasticity in an experimental mouse model of multiple sclerosis (MS). Baclofen reduced spasticity and served as a positive control. Sativex (10 mg/kg) was just as effective as baclofen, providing supportive evidence for Sativex use in the treatment of spasticity in MS.

Continuation of treatment of drug misusers between primary and secondary care in the South West

Focal points

Interventions for helping people recognise early signs of recurrence in bipolar disorder

BACKGROUND

Recurrence rates for bipolar disorder are high despite effective treatments with mood stabiliser drugs. Self-help treatments and psychological treatments that teach patients to recognise and manage early warning symptoms and signs (EWS) of impending manic or depressive episodes are popular with patients. The main aim of such interventions is to intervene early and prevent bipolar episodes, thereby increasing the time to the next recurrence and preventing hospitalisation.

OBJECTIVES

To compare the effectiveness of an EWS intervention plus treatment as usual (TAU ) versus TAU (involving and not involving a psychological therapy) on time to manic, depressive and all bipolar episodes (the primary outcome), hospitalisation, functioning, depressive and manic symptoms.

SEARCH STRATEGY

Relevant studies identified by searching Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (CCDANCTR-Studies and CCDANCTR-References - searched on 20/10/2005), supplemented with hand searching the journal Bipolar Disorders, searching the UK National Research Register, checking reference lists of included studies and contacting authors.

SELECTION CRITERIA

Only randomised controlled trials (RCTs) were included. Participants were adults with a diagnosis of bipolar disorder based on standardised psychiatric criteria.

DATA COLLECTION AND ANALYSIS

Two reviewers independently rated trials for inclusion. Data were extracted from included trials by reviewers using a data extraction sheet. Authors of all the included studies were contacted for any additional information required. Time to recurrence data was summarised as log hazard ratios, dichotomous data as relative risk and continuous data as weighted mean difference, using random effects models to calculate effect size only when there was heterogeneity in the data.

MAIN RESULTS

Eleven RCTs were identified, but only six provided primary outcome data. All six RCTs were of high quality. Time to first recurrence of any type (RE, hazards ratio 0.57, 95% CI 0.39 to 0.82), time to manic/hypomanic episode, time to depressive episode, and percentage of people hospitalised and functioning favoured the intervention group. Neither depressive nor hypomanic symptoms differed between intervention and control groups.

AUTHORS' CONCLUSIONS

This review shows a beneficial effect of EWS in time to recurrence, percentage of people hospitalised and functioning in people with bipolar disorder. However, the absence of data on the primary outcome measure in so many included studies is a source of concern and a potential source of bias. Mental health services should consider routinely providing EWS interventions to adults with bipolar disorder, as they appear to reduce hospitalisation and therefore may be cost-effective.

Glutamate-stimulated peroxynitrite production in a brain-derived endothelial cell line is dependent on N-methyl-D-aspartate (NMDA) receptor activation

There is accumulating and convincing evidence indicating a role for glutamate in the pathogenesis of the human demyelinating disease multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE), the animal model of MS, demonstrate that pharmacological inhibition of specific glutamate receptors suppresses neurological symptoms and prevents blood-brain barrier (BBB) breakdown. The mechanisms through which glutamate influences BBB function during EAE remain unclear. Glutamate triggers the production of nitric oxide and superoxide, which can lead to the formation of peroxynitrite (ONOO(-)). Recent studies have implicated ONOO(-) in the loss of neurovascular integrity during EAE. We propose that glutamate contributes to BBB breakdown via the actions of ONOO(-). The present investigation examined glutamate-induced ONOO(-) formation in the b.End3 brain-derived endothelial cell line. b.End3 cells were incubated with a concentration range of glutamate and ONOO(-) production was assessed over time. Results showed a concentration- and time-dependent increase in ONOO(-) levels in glutamate-treated cells that were suppressed by selective and non-selective inhibitors of ONOO(-)-mediated reactions. Specific activation of b.End3-associated NMDA receptors also resulted in a concentration-dependent increase in ONOO(-) production. The ability of b.End3 cells to respond to the presence of glutamate was confirmed through the detection of NMDA receptor immnuoreactivity in cell extracts. In addition, the use of the NMDA receptor antagonists MK-801 and memantine reduced glutamate-mediated ONOO(-) generation from b.End3 cells. The data reinforce the important relationship between glutamate and the NMDA receptor, positioned at neurovascular sites, which may be of particular relevance to the pathogenesis of demyelinating disease.

Asbestos-related disease

Until the 1980s, asbestos was widely used throughout the UK. The incidence of asbestos-related disease is still climbing because of the long delay in developing the disease from the initial exposure. The spectrum of diseases encompasses malignant mesothelioma, asbestosis, asbestos-related lung carcinoma and benign pleural disease, including pleural plaques.

Regional access to acute ischemic stroke intervention

BACKGROUND AND PURPOSE

Benefit-risk ratios from recombinant tissue plasminogen activator (rtPA) therapy for acute ischemic stroke demonstrate lack of efficacy if intravenous administration is commenced beyond 3 hours of symptom onset. We undertook to enhance therapeutic effectiveness by ensuring equitable access to rtPA for patients affected by acute ischemic stroke within a 20 000 km(2) population referral base served by a tertiary facility.

METHODS

Representatives of all provider groups involved in emergency medical services developed a Regional Acute Stroke Protocol (RASP), a coordinated regional system response by dispatch personnel, paramedics, physicians, community service providers, emergency and inpatient staff in community hospitals, and the tertiary facility acute stroke team.

RESULTS

As of July 26, 1999, all ambulance services in Southeastern Ontario began bypassing the closest hospital to deliver patients meeting the criteria for the RASP to the Kingston General Hospital. At 12 months, approximately 403 ischemic strokes have occurred in the region, the RASP has been activated 191 times, and 42 patients have received rtPA.

CONCLUSIONS

We conclude that (1) acute stroke patients in Southeastern Ontario have improved access to interventions for stroke care; (2) geography of the region is not a barrier to access to interventions for patients with acute stroke; and (3) acute ischemic stroke patients treated with rtPA account for 5% of all acute strokes and 10% of all ischemic strokes in this region.

L-arginine modifies free radical production and the development of experimental allergic encephalomyelitis

OBJECTIVES AND DESIGN

The present investigation examines the effects of increasing central nervous system (CNS) levels of nitric oxide (NO), via the administration of L-arginine, on the development of experimental allergic encephalomyelitis (EAE).

SUBJECTS

EAE was induced in male Lewis rats (200-250 g).

TREATMENT

Normal rats were orally dosed with L-arginine (300 mg/kg body weight) once daily for 12 days. EAE-sensitised animals received L-arginine (300 mg/kg body weight) once daily from day 1 to 12 post-inoculation.

METHODS

Neurological and histological development of EAE were assessed. In addition, CNS cytosol levels of nitrite, superoxide and hydrogen peroxide were measured. Results were analysed using the Mann Whitney U-test and Chi-squared test.

RESULTS

L-arginine administration significantly delayed disease onset (p < 0.05) and reduced the severity of neurological (p < 0.05) and histological (p < 0.001) signs of EAE. Treatment with L-arginine caused a significant elevation in CNS nitrite concentrations (p < 0.05) which in EAE-sensitised animals was associated with a concomitant and dramatic decrease in superoxide (p < 0.05) and hydrogen peroxide (p < 0.05) levels.

CONCLUSIONS

The results suggest that NO may act as a protective molecule during the development of EAE possibly via the modulation of oxidant-mediated neuroinflammation.

The detection and quantitation of inflammation in the central nervous system during experimental allergic encephalomyelitis using the radiopharmaceutical 99mTc-RP128

RP128 is a novel agent which readily chelates 99mTc to form a radiopharmaceutical which binds in vivo to the tuftsin receptor located specifically on neutrophils and monocyte-macrophages, therefore removing the need for in vitro cell labelling prior to intravenous administration. We have assessed the ability of 99mTc-RP128 to detect central nervous system (CNS) inflammation in experimental allergic encephalomyelitis (EAE), an animal model of the human disease multiple sclerosis. The radiopharmaceutical was recorded at significantly increased levels in all EAE diseased CNS tissues, compared to normal and control samples, at 0.5, 1 and 3 h post-injection using a dual radioisotope technique to correct for non-extravasated tracer (P<0.05). Moreover, extravascular accumulation of the agent could be clearly demonstrated in inflammatory tissues with minimal loss of sensitivity when the secondary isotopic correction for blood volume was omitted. In addition, 99mTc-RP128 successfully monitored glucocorticoid suppression of inflammation (P<0.05), recording a typical dose-response to increasing steroid concentration. Clearly, 99mTc-RP128 can quantitatively detect CNS inflammation and assess responses to therapy indicating potential value as an imaging agent both clinically and as a research aid. Furthermore, the rapid in vivo labelling by 99mTc-RP128 of specific inflammatory cells combined with the ability to monitor the progress of anti-inflammatory therapeutics may recommend the agent for use in a variety of inflammatory conditions.

Physicians' perceptions of the effect on clinical services of an alternative funding plan at an academic health sciences centre

BACKGROUND

In July 1994 an alternative funding plan for clinical services (global funding instead of fee-for-service payment) was established at the Southeastern Ontario Health Sciences Centre, Kingston, Ont. This study describes the perceptions of the referring physicians and consultants of the effects of the alternative funding plan 2.5 years after it was initiated.

METHODS

A questionnaire was mailed to all physicians in the Kingston area in November 1996. Information was collected on demographics, referring physicians' perceptions of the funding plan's impact on their practices, consultants' perceptions of its impact on their activities, perceptions of referring and consultant physicians of its impact on services provided by consultants, and attitudes toward alternative funding in the context of the Ontario health care system.

RESULTS

Of the 772 physicians 531 (68.8%) returned a completed questionnaire (323 referring physicians and 208 consultants). A sizeable proportion of the referring physicians (126 [39.0%]) indicated that they were referring fewer patients to consultants at the study centre. They did not think that their practice volume had increased, but they did report spending more time on complex cases and on patient care after referral or hospital stay, and more time coordinating community care after hospital stay. Of the consultants 81 (38.9%) believed that their time spent on patient care had increased. No consistent impact on time spent on research or teaching activities was perceived. A total of 54 (26.0%) of the consultants were concerned about the impact of the alternative funding plan on quality of care. A significant proportion of the respondents (399 [75.1%]) believed that outpatient waiting times had increased, and 116 (35.9%) of the referring physicians believed that consultants were not as available by telephone. Most (220 [68.1%]) of the referring physicians believed that the funding change had had a negative effect on health care services in the region, and 87 (41.8%) of the consultants agreed. Nevertheless, the respondents believed that other factors such as funding cuts, hospital bed closures and staff layoffs were much more responsible than the alternative funding plan for their negative perceptions.

INTERPRETATION

The alternative funding plan appears to have had an impact on the practices of individual physicians. However, it was not the focus for significant opposition or support from either consultants participating in the funding plan or referring physicians.

Effect of concentrated red grape juice consumption on serum antioxidant capacity and low-density lipoprotein oxidation

This study examines whether the beneficial antioxidant effects of red wine can be reproduced by nonalcoholic red grape juice concentrate. Seven subjects consumed 125 ml concentrate daily for 7 days. Following first ingestion there was a rise in serum total antioxidant capacity (TAC) from 441 to 478 mumol/l at 60 min (p < 0.005). On day 8, TAC was 50 mumol/l higher than at baseline (p < 0.05). There was reduced susceptibility of low-density lipoprotein (LDL) to oxidation. Red grape juice concentrate ingestion results in increased serum antioxidant capacity and protection of LDL from oxidation and thus nonalcoholic red grape extract may have similar beneficial effects to red wine.

Substituting home care for hospitalization: the role of a quick response service for the elderly

The purpose of the present study was to examine the role of a rapid access home-based service as a means for the elderly to avoid admission to an acute-care hospital. The setting for the study included emergency departments in three acute care hospitals and a home care program in a mid-size Canadian city. Multiple sources of information were obtained to evaluate the service. Hospital emergency department records and home care records were reviewed. Patients who participated in the service (n = 96) and physicians and nurses (n = 119) who had involvement with the service were surveyed appraising the service in terms of relevance, access, quality and coordination. Study results revealed that elderly women with multiple health problems who lived alone were the most frequent users of the service. The majority of the patients admitted to the service presented with problems of a functional nature that were the result of a fall or mobility problems. The results indicated that the service did avert hospital admissions and facilitated a process by which patients could avoid the intermediate step of hospitalization before placed in a higher level of care or returning to previous levels of functioning. Economic analysis indicated that the value of the service stemmed from the benefits to patients and caregivers rather than from cost savings offered to acute care hospitals.

Regulation of chronic relapsing experimental allergic encephalomyelitis by endogenous and exogenous glucocorticoids

Expression, development and resolution of the acute form of experimental allergic encephalomyelitis (EAE), typically induced in the highly susceptible Lewis rat, are closely regulated by endogenous corticosteroids. Administration of synthetic glucocorticoids also efficiently controls the manifestation of disease. The pivotal role played by the corticosteroids in modifying the induction and progression of EAE is further emphasised by a reversal of corticoid-mediated effects through adrenalectomy or treatment with the steroid receptor antagonist RU486 (mifepristone). Chronic relapsing EAE (CREAE) is characterised by acute symptoms, periods of remission and re-emergence of disease. The mechanisms governing the development of CREAE are unclear, but may require the regulatory influence of endogenous glucocorticoids. The current study has monitored circulating corticosteroids throughout the course of CREAE in the Biozzi ABH mouse and found that major fluctuations in systemic levels coincide with the relapsing-remitting phases of the disease. Furthermore, increasing circulating adrenocorticoids through administration of the steroidal compound dexamethasone markedly suppresses the occurrence of acute signs. The importance of the glucocorticoids in controlling CREAE is again highlighted by the intensification of symptoms and reduction in the survival rate of inoculated mice receiving RU486 prior to and during the acute phase of disease. The data reinforce the amelioratory actions of exogenous and naturally occurring glucocorticoids in the pathogenesis of EAE and extend earlier observations in the monophasic disease by demonstrating corticosteroid-dependent effects in a relapsing-remitting mouse model.

MK-801 limits neurovascular dysfunction during experimental allergic encephalomyelitis

Increased permeability of the blood-brain barrier (BBB) is a characteristic of the demyelinating disease multiple sclerosis and the animal counterpart experimental allergic encephalomyelitis (EAE). In physically traumatized cerebral tissue neurovascular damage, linked with activation of the cerebroendothelial-bound N-methyl-D-aspartate receptor, can be treated with the antagonist MK-801. We have examined the ability of MK-801 to modify BBB leakage and the development of disease during EAE. Prophylactic MK-801, at 0.15 mg kg(-1) body weight suppressed neurovascular breakdown, measured by a dual radioisotope technique, and significantly reduced neurological deficits (P < .05), but not perivascular lesions. A 2-fold increase in administered MK-801 completely prevented abnormal extravasation in cerebella (P < .01) and significantly inhibited BBB disruption in medulla-pons (P < .05) and cervical spinal tissues (P < .01). High-dose treatment also restricted disease development (P < .01) and lesion formation (P < .05). Therapeutic MK-801, at 0.30 mg kg(-1) body weight, completely counteracted neuroendothelial leakage in cerebella (P < .05) and inhibited BBB dysfunction in remaining tissues without restricting inflammatory cell invasion. However, doubling the dose did not further enhance suppression of neurovascular breakdown. Our use of MK-801 to control major features of EAE strongly implicates N-methyl-D-aspartate receptor-dependent mechanisms in disease development and prompts consideration of a role for the receptor in the pathogenesis of human demyelinating conditions.

A pharmacological study on the role of nitric oxide in the pathogenesis of experimental allergic encephalomyelitis

OBJECTIVE AND DESIGN

The study examines the effects of nitric oxide synthase (NOS) inhibitors on the development of neurological EAE and the levels of nitrite in the central nervous system (CNS) during established disease.

MATERIALS

EAE was induced in male Lewis rats (200-250 g).

TREATMENT

Rats received NG-nitro-L-arginine methyl ester (L-NAME) (30 mg/kg body weight) day 7 to 12 post-inoculation (P.I.), 7-nitroindazole (10 mg/kg) day 7 to 11 P.I. or aminoguanidine (200 or 400 mg/kg) day 1 to 12 P.I.

METHODS

Neurological symptoms were assessed and CNS cytosol nitrite and protein levels measured. Results were analysed using the Mann Whitney U-test and the Fischer exact probability test.

RESULTS

Symptoms of EAE were associated with a significant elevation in CNS nitrite (p < 0.001). Treatment with NOS inhibitors caused a marked reduction in nitrite levels (p < 0.01). However, in some experiments, vehicle administration also reduced CNS nitrite content (p < 0.05). Although neurological disease was suppressed in EAE-sensitised rats receiving L-NAME (2 +/- 0.3 vs 3 +/- 0.3 mean peak severity +/- SEM) and 7-nitroindazole (1 +/- 0.3 vs 3 +/- 0.3, p < 0.01) comparable inhibition was achieved by respective vehicle treatment (p < 0.01). In contrast, neither aminoguanidine nor corresponding vehicle altered disease development.

CONCLUSIONS

Drug-induced reductions in CNS nitrite levels during EAE are not always associated with a suppression of neurological symptoms, which suggests NO is not of primary importance in disease pathogenesis. In addition, the study emphasises the strict requirement for appropriate controls when assessing the efficacy of drugs on the course of EAE.

Lack of influence of intestinal transit on oxidative status in premenopausal women

OBJECTIVE

There are reasons for believing that diet can alter the risk of malignancy by alteration of the body's oxidative status. Intestinal contents and enterohepatically recirculated substances are influenced by intestinal transit rate. A low fibre diet has been linked to the increase in constipation seen in countries consuming a westernized diet, as well as to the aetiology of many diseases. We studied the effects of altering intestinal transit rates and of wheat bran on oxidative status.

DESIGN

40 premenopausal women were randomized to receive dietary supplements of wheat bran, senna or loperamide for the length of two menstrual cycles. Dietary records, whole gut transit time (WGTT) and plasma lipid peroxides, measured as TBARS (specifically malondialdehyde) were determined at the beginning and end of each intervention.

SETTING

University department of Medicine, Bristol Royal Infirmary.

RESULTS

36 volunteers completed the study. WGTT increased in those receiving loperamide and decreased in those receiving senna. The decrease in WGTT was not significant in those receiving wheat bran. Diets did not change. There were no changes in TBARS, cholesterol, triglyceride or TBARS adjusted for cholesterol and triglyceride, during any intervention.

CONCLUSIONS

Dietary supplementation with wheat bran and pharmacological alteration of intestinal transit had no influence on oxidative status or on plasma cholesterol or triglycerides.

Recent advances in the pharmacological control of experimental allergic encephalomyelitis (EAE) and the implications for multiple sclerosis treatment

The autoimmune, cell-mediated condition experimental allergic encephalomyelitis (EAE) is the representative model for the inflammatory central nervous system disease MS. EAE has been extensively employed to determine the efficacy of pharmacological agents that may be of ultimate use in the treatment of MS. A wide variety of drugs has been examined for activity in EAE but, over the last decade, three groups of compounds have emerged with clear and reproducible ability to modify significantly the onset and progression of the disease. The immunosuppressants, the modulators of catecholamine activity and the antineoplastic agents have convincingly altered the course of EAE and, as a consequence, provided understanding of the mechanisms of disease expression and offered further insight into the pathogenesis of MS. The article stresses the usefulness of EAE as a model to identify prospective pharmacological treatments for MS and, in particular, considers those compounds subsequently assessed for their ability to interfere with the progression of the human disease.

Changes in the cellular distribution of lipocortin-1 (Annexin-1) in C6 glioma cells after exposure to dexamethasone

Glucocorticoid-induced changes in cellular levels of Lipocortin-1 (LC-1) (Annexin 1) in C6 glioma cells were determined by electrotransfer and immunoblotting techniques. Separate cell protein fractions were prepared to study the influence of the glucocorticoid steroid, dexamethasone, on LC-1 localisation. Cells were grown in steroid-depleted medium and exposed to dexamethasone (10(-8) and 10(-7) M) for 2, 6, and 16 hr. The glucocorticoid-dependent changes in cellular content of LC-1 were both dose- and time-related. Increases above control levels in intracellular and extracellular LC-1 content were detected with the greatest changes occurring at the cell surface. The glucocorticoid-dependent alteration in LC-1 distribution in C6 glioma cells was attenuated by the protein synthesis inhibitor, cycloheximide, indicating the involvement of de novo LC-1 synthesis. The significance of these results is discussed in relation to the current concept that some of the anti-inflammatory effect of glucocorticoids occurs through the action of extracellular LC-1.

Inhibition of blood-brain barrier disruption in experimental allergic encephalomyelitis by short-term therapy with dexamethasone or cyclosporin A

Double radioisotope measurement of neurovascular integrity in Lewis rats inoculated for experimental allergic encephalomyelitis (EAE) showed abnormal elevation of albumin extravasation in the cerebellum, medulla-pons and cervical spinal cord at the time of clinical manifestation. Therapeutically administered dexamethasone (Dex) (0.1-1 mg/kg body weight) or cyclosporin A (CsA) (25-75 mg/kg body weight) dose-dependently reduced albumin movement across the blood-brain barrier (BBB). Dex at a dose of 1 mg/kg completely suppressed abnormal BBB permeability in all tissues (P < or = 0.001), while CsA at the highest dose of 75 mg/kg achieved highly significant (P < or = 0.001), but not complete, suppression of aberrant barrier leakage in the areas studied. The implications of these findings to possible drug action at the immunocompromised cerebrovasculature are discussed.