POS1241 THE IMPACT OF THE COVID-19 PANDEMIC ON PHYSICAL FUNCTIONING AND MENTAL WELLBEING IN 824 PATIENTS WITH RHEUMATIC DISEASE OVER 8 MONTHS: PHYSICAL FUNCTIONING DECLINES

Background:

Worldwide the detrimental consequences of the COVID-19 pandemic on physical and psychological health have been recognised. Social distancing and isolation measures have negatively impacted physical functioning (PF) and mental health (MH), and are known to have reduced physical activity (PA) generally within the population. A significant proportion of patients with autoimmune rheumatic disease (ARD) are considered ‘clinically extremely vulnerable’ (CEV), at high risk from COVID19 and been advised to follow stricter social distancing precautions than the general population. Evidence in ARD patients highlights the importance of PA in maintaining physical and psychological wellbeing. Prior to the pandemic limitations in both PF and MH in patients with ARD were recognised and early in the pandemic MH was noted to be impacted by distancing measures in this population.

Objectives:

This is an interim report of a research study (clinicaltrials.gov NCT04542031) exploring the impact of the COVID19 pandemic on the physical and psychological wellbeing of patients with rheumatic disease, to inform guidelines and target service provision as the pandemic continues.

Methods:

We distributed two web-based surveys, eight months apart during the first (April-2020) and second wave (December-2020) of the pandemic. Surveys were communicated via a linked mobile-phone SMS message, to all rheumatology patients with a validated mobile number under follow-up at the Royal Wolverhampton Trust. We assessed patients using the Short Form-12 version 2 made up of mental (MCS) and physical component scores (PCS). For each survey, data were collected 4-weeks following distribution; comparative analysis was conducted using SPSS version-27.

Results:

Initial surveys were sent to 7911 active follow up patients; 1694/7911 (21.4%) responded and consented for further follow up, of which 1636 were linked to a validated mobile number. 899/1636 (55.0%) responded to the second survey and 824/899 (91.7%) responses were linked across both surveys. These 824 patients were predominately female (69.5%), aged 61 years and 76.3% had an ARD; 388/824 patients were CEV, 436 were in the comparator group. For the CEV group, scores remained significantly lower than the comparator for PCS (survey 1: 36.40 vs 39.61 [P<0.001], survey 2: 36.11 vs 38.66 [P<0.001]) and MCS (41.61 vs 43.44 P<0.001; 41.19 vs 43.60 [P<0.001]); there was no deterioration in CEV scores. In the comparator group, while MCS did not differ in patients with ARD, PCS significantly decreased (1.39; 95% CI: 0.69, 2.08; P<0.001); PCS in the non-inflammatory group did not significantly change (-0.23, P=0.65).

Conclusion:

These preliminary data suggest that while the physical and mental health of CEV patients is significantly lower in this cohort, surprisingly, neither aspects of health have been worsened by the impacts of the pandemic over an 8-month period. However, the physical functioning of patients with ARD significantly decreased in this time, which may reflect the reduction in PA faced by society, and reduced contact with secondary care services. These data suggest services need to adapt to provide additional support to patients with ARD to maintain physical functioning during the pandemic. Further work exploring the evolving pattern of the physical and psychological responses to the pandemic is ongoing.

Acknowledgements:

We would like to thank the Hibbs Lupus Trust.

Disclosure of Interests:

None declared

OP0009-PARE SUCCESSFUL PATIENT EDUCATION ON COVID-19 VACCINE SAFETY IN A LARGE RHEUMATOLOGY COHORT USING INTERACTIVE MOBILE-PHONE VIDEO TECHNOLOGY: CONTEXT, RESULTS, AND NEXT STEPS

Background:

There are reported concerns of patient misunderstanding of the COVID-19 pandemic and vaccination safety. It is particularly important that these are understood in patients taking complex immunusuppressive therapies. Rapid delivery of targeted and up-to-date video messages from clinicians sent directly to patients could address patient uncertainty, and improve COVID-19 vaccination uptake. Innovative SMS (short message service) based video message has already shown promise in delivering COVID-19 information to patients [1]. We present our experience in creating a tailored vaccine information video sent directly to our large cohort of patients in the UK with a range of rheumatic diseases and report on the learning points going forward.

Objectives:

Our three objectives were: (1) educate our patients using an interactive mobile video information resource outlining the safety of the COVID vaccination in these patient groups; (2) better understand our patients’ views of the COVID-19 vaccine; (3) evaluate the patient experience of this approach.

Methods:

We designed and recorded an 8-minute interactive web-based video delivered education resource designed for mobile phones. This included: aims of the video; details of licenced vaccines; UK vaccination schedule; frequently asked questions; links to national charity resources; our clinician recommendations; a rheumatologist being vaccinated; case studies; and summary data. We produced a simple mobile phone web-based evaluation of the resource, including anonymised patient demographics, their understanding of the safety of the vaccine pre/ post video, and their user experience. Resource and evaluation were piloted by local healthcare professionals, our Patient Participation Group, a national charity, and approved by senior management. We distributed this to our follow-up patient cohort via our hospital SMS provider on 21.12.20, at the start of roll-out of UK vaccines, containing a link to the resource and evaluation.

Results:

Of a cohort of 10,981 patients, we had 8886 mobile phone numbers. At Day 14, we recorded 2358 video views (26.3%) and 664/2358 completed evaluations (28.1%). Only one person reported being unable to watch the video. Before watching the video, 348/664 patients (52.4%) were unsure if the vaccine was safe and/or recommended for them, rising to 626/664 (94.3%) post-video.Reasons for uncertainty after the video (38/664) included drug allergy and fertility concerns. Following the video, 509/664 patients (76.6%) reported that they were more likely to have the vaccination. The majority of the patients (614/660, 93.0%) agreed that the method was a helpful method to share such information.Age distribution of our whole cohort, patients with mobile phones, and responders were similar: Age >50 was 80.4%,76.3%,and 88.6% respectively. A large proportion was treated with immunosuppressive medication (61.3% conventional DMARD, 39.4% biological DMARD and 17.6% corticosteroids). Gender and case mix for responders were similar to published data from our cohort: female 74.0%; rheumatoid arthritis commonest disease (389/664, 58.5%).

Conclusion:

To our knowledge, this is the first study to show the potential for SMS linked interactive multimedia message for patient education. The multimedia component allows users to easily navigate to relevant sections, and access a choice of linked resources. We demonstrate this low-cost technology is simple, effective and well placed to assist physicians in educating patients during a time when face-to-face contact is proving to be difficult. We have shown high levels of patient satisfaction, reassurance, and self-reported behaviour change. Such technology has potential utility for national bodies, primary and secondary care groups, and merits further research.

References:

[1]The Lancet Rheumatology. Rapid distribution of information by SMS-embedded video link to patients during a pandemic. June 2020,Volume2,Number 6,e309-e368

Acknowledgements:

We would like to thank the Hibbs Lupus Trust, and our Patient Participation Group.

Disclosure of Interests:

None declared

The impact of COVID-19 on rheumatology patients in a large UK centre using an innovative data collection technique: prevalence and effect of social shielding

OBJECTIVES

We sought to gain insight into the prevalence of COVID-19 and the impact stringent social distancing (shielding) has had on a large cohort of rheumatology (RD) follow-up patients from a single large UK centre.

METHODS

We linked COVID-19-related deaths, screening and infection rates to our RD population (1.2.20-1.5.20) and audited active rheumatology follow-up patients through survey data communicated via a linked mobile phone SMS message. We assessed epidemiology, effect of stringent social distancing (shielding) and quality of life (HRQoL) by Short Form 12 (SF12).

RESULTS

There were 10,387 active follow-up patients, 7911 had linked mobile numbers. 12/10,387 RD patients died from COVID-19 (0.12%); local population 4131/7,415,149 (0.12%). For patients with mobile phones, 1693/7911 (21%) responded and of these, 1605 completed the SF12. Inflammatory arthritis predominated 1174/1693 (69%); 792/1693 (47%) were shielding. Advice on shielding/distancing was followed by 1372/1693(81%). 61/1693 (4%) reported COVID-19 (24/61 shielding); medication distribution was similar in COVID and non-COVID patients. Mental SF12 (MCS) but not physical (PCS) component scores were lower in COVID (60) vs. non-COVID (1545), mean differences: MCS, - 3.3; 95% CI - 5.2 to - 1.4, P < 0.001; PCS, - 0.4; 95% CI, - 2.1 to 1.3). In 1545 COVID-negative patients, those shielding had lower MCS (- 2.1; 95% CI - 2.8 to - 1.4) and PCS (- 3.1, 95% CI - 3.7 to - 2.5), both P < 0.001.

CONCLUSIONS

Our full RD cohort had no excess of COVID deaths compared to the general local population. Our survey data suggest that shielding adversely affects both mental and physical health in RD. These data broaden our understanding of shielding, indicating need for further study.

A pragmatic proposal for triaging DXA testing during the COVID-19 global pandemic

The COVID-19 pandemic has resulted in huge disruption to healthcare provision, including to dual-energy X-ray absorptiometry (DXA) imaging. Increased waiting lists for DXA from the pandemic mean potential long and uncertain delays in treatment for osteoporosis. To address these increased waiting lists, we propose a rapid, simple, one-stop algorithm incorporating medication use (aromatase inhibitor, corticosteroid) and clinical risk stratification supplementing a standard FRAX assessment. Our pragmatic algorithm produces a recommendation to treat empirically, image with DXA, or observe. If applied, we model a significant reduction in DXA scan requirements with a corresponding reduction in treatment delays for those awaiting DXA. We estimate this will reduce DXA scan numbers by about 50%, whilst pragmatically ensuring those with the highest clinical need correctly receive treatment without delay. This algorithm will help many clinicians including general practitioners/family physicians prioritise DXA when they may not always have the expertise to make this judgement based on clinical information alone. Although we have used UK guidelines as an example, this approach is flexible enough for adaptation by other countries based on their local guidelines, licensing, prescribing requirements, and DXA waiting list times. There are some limitations to our proposal. However, it represents one way of managing the uncertainty of the current COVID-19 pandemic.

SAT0650-HPR WHAT CAN WE LEARN FROM A ROUTINE FRAILTY ASSESSMENT IN RHEUMATOLOGY? A SERVICE EVALUATION OF 170 NEW PATIENT REFERRALS TO A SINGLE RHEUMATOLOGY CENTRE

Background:

Frailty is common among patients with rheumatological diseases, and there is increasing evidence that it is associated with poorer outcomes. Frailty scores worsen during the course of chronic inflammatory arthritis (IA) and connective tissue disease (CTD). Existing tools such as the Rockwood Clinical Frailty Scale (a nine-point scale from 1 very fit- 9 severely frail) allow for rapid frailty assessment by doctors and nurses. Frailty assessment is recommended by NHS England as an important public health opportunity for targeted interventions for both primary and secondary care. We have limited understanding of frailty in rheumatology new patient cohorts, and it is not routinely assessed in most centres. We report the feasibility and utility of frailty scores in patients referred to rheumatology, and association with final diagnosis.

Objectives:

This service evaluation assesses the utility and feasibility of implementing the Rockwood Clinical Frailty Score for new patient referrals at a single UK centre.

Methods:

New patient assessments at a rheumatology consultant general new patient clinic were prospectively coded over 9-months (March- December 2019). Anonymised coded demographic data included: age, gender, referral source, history of depression, RFCS and clinical diagnosis (coded against established categories, those requiring further tests coded ‘awaiting investigations’). RCFS coding was assisted by an online validated pictorial aide memoir for coding.

Results:

Of the 181 referrals, 11 (6%) were excluded for incomplete data. The mean age of the remaining 170 patients was 53 years (SD 16.8; range 17-87), predominantly female (123/170; 72%). Most referrals, 57% (97/170) were from primary care, 23% (39/170) from musculoskeletal integrated triage services, 5% (9/170) from orthopaedics, 4% (7/170) from gastroenterology; 18 were from 12 secondary-care specialties. The RCFS was: mean 2.6 (median 2, range 1-7) with depression in 61/170 (36%), but no effect of this on mean RCFS (2.6 in both). RCFS increased with age (70-79, n=21, mean 2.9; >80, N=12, 4.3). The majority of patients had non-inflammatory (NI) diagnoses (119/170, 70%) e.g. osteoarthritis, fibromyalgia. Overall 19% (32) ‘inflammatory arthritis’ (IA; rheumatoid arthritis, psoriatic, undifferentiated inflammatory arthritis, gout); 4% (6) were diagnosed with a form of connective tissue disease (undifferentiated CTD; SLE; Sjogren’s syndrome); 8% (13) were awaiting further investigations. Patients in both the NI and IA category were found to have an average RCFS of 2.6 (SD, NI 1.1; IA 0.9). Patients who received a diagnosis of CTD had an average RCFS of 3.5 (SD 1.8). We identified 30 patients who scored four or more (vulnerable/ at risk) for targeted intervention by therapy and allied health professionals. The RCFS was positively evaluated by clinicians.

Conclusion:

RFCS was simple to introduce to our centre and has provided us with additional data to plan our service provision for primary and secondary care support for our cohort. Our new patients with CTD, and who were elderly had higher frailty scores, we found no association between frailty and depression or presence of IA or NI. The RCFS was easy to use and can be integrated into routine clinical practice for new and follow up patients. Further studies are required to support these findings.

References:

[1]Haider, S., Grabovac, I., Berner, C., et al. Frailty in seropositive rheumatoid arthritis patients of working age: a cross-sectional study. Clinical and experimental rheumatology. 2018.

[2]Katz PP, Andrews J, Yazdany J, et al. Is frailty a relevant concept in SLE? Lupus Science & Medicine 2017;4:e000186.

[3]ALPAY M, CASSEM EH. Diagnosis and treatment of mood disorders in patients with rheumatic disease. Annals of the Rheumatic Diseases 2000;59:2-4.

Disclosure of Interests:

None declared

THU0301 OUTPATIENT REFERRAL WITH A POSITIVE ANCA? A SINGLE-CENTRE EVALUATION OF THE IMPACT OF IMPLEMENTING THE 2017 REVISED INTERNATIONAL CONSENSUS ON ANCA TESTING FROM 1547 NEW PATIENT REFERRALS

Background:

Anti-neutrophil cytoplasmic antibodies (ANCAs) are valuable laboratory markers used in the detection of medium and small-vessel vasculitis: granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis and microscopic polyangiitis. Historically, and in our own centre, ANCAs are screened for using indirect immunofluorescence (IIF) with antigen-specific immunoassays being performed on IIF-ANCA positive results. While highly sensitive, IIF has a low specificity compared to antigen-specific immune-assay for MPO and PR3. Anecdotally, positive IIF ANCA results often trigger rheumatology referrals. A 2017 International consensus statement has recommended ten clinical indications for requesting ANCA, and suggested high quality immunoassays are the preferred screening method, without the categorical need for IIF.

Objectives:

This service evaluation explores the local impact and implications of adopting the 2017 International Consensus on ANCA testing by evaluating new patient referrals to a single UK rheumatology centre.

Methods:

New out-patient referrals to a single consultant rheumatologist at one UK centre were collected over 40-months (2016-19) and prospectively coded by referral indication from the clinical letter prior to clinical assessment. Data collected included: anonymised baseline demographics, referral source, key features for referral, and diagnosis following assessment. Referral text was coded using clinical reasoning theory, to identify up to four ‘key-features’ of the referral, typed by the clinician as free text. This included clinical findings, suspected diagnosis, ANCA testing (MPO/PR3 status), other autoantibodies, arthralgia, synovitis, or other important features (e.g. rash, Raynaud’s phenomenon). Diagnosis at the visit was coded against established rheumatological diagnoses. We retrospectively identified any patient where ANCA/ MPO/PR3 formed a key part of the referral, using electronic text search tools.

Results:

A total of 1748 referrals were seen, 177 (10.1%) were excluded due to incomplete data. This left 1547 for analysis, of these 18 (1.2%) had been referred with an ANCA IIF positive result as a key component for the referral. The 18 ANCA positive were predominantly female (16/18) and had a mean age of 49 (SD 16.6). The majority of referrals were initiated primary care (16/18); the remaining referrals were from haematology and ophthalmology. The majority (17/18, 94%) tested negative for MPO and PR3, 1/18 (6%) was PR3 antibody positive (known inflammatory bowel disease). Retrospectively, none of the ANCA requests would have met the 2017 gating criteria for testing. In total 13/18 patients were given an additional diagnosis: Fibromyalgia 6 (28%); Soft tissue rheumatism 4 (22%); undifferentiated inflammatory arthritis 1; reactive arthritis 1; biomechanical joint pain 1; probable connective tissue disease 1.

Conclusion:

This service evaluation shows that routine outpatient referrals with positive IIF ANCA represent a small but significant proportion of referrals to our centre (1.2%). The vast majority of these would be filtered out with a gating strategy. This evaluation demonstrates the low specificity of IIF ANCA without any suggestive clinical symptoms. By adopting MPO/PR3 immune-assays as the primary screening method, the vast majority of these referrals (17/18, 94%) would have tested ‘negative’, reducing uncertainty for patients and primary care clinicians. None of these patients were diagnosed with vasculitis. These data support adoption of the 2017 Consensus Statement across our, and other units, to reduce unnecessary referrals, uncertainty, and cost. Our electronic requesting system allows for the introduction of an ANCA gating strategy. These data can be used to educate primary care teams regarding indications and interpretation of ANCA testing.

References:

[1]Broeders S, Goletti S, Tomasi J, et alRevised 2017 international consensus on ANCA testing in small vessel vasculitis. Annals of the Rheumatic Diseases 2019;78:e113.

Disclosure of Interests:

None declared

Free Nano-Object Ramsey Interferometry for Large Quantum Superpositions

We propose an interferometric scheme based on an untrapped nano-object subjected to gravity. The motion of the center of mass (c.m.) of the free object is coupled to its internal spin system magnetically, and a free flight scheme is developed based on coherent spin control. The wave packet of the test object, under a spin-dependent force, may then be delocalized to a macroscopic scale. A gravity induced dynamical phase (accrued solely on the spin state, and measured through a Ramsey scheme) is used to reveal the above spatially delocalized superposition of the spin-nano-object composite system that arises during our scheme. We find a remarkable immunity to the motional noise in the c.m. (initially in a thermal state with moderate cooling), and also a dynamical decoupling nature of the scheme itself. Together they secure a high visibility of the resulting Ramsey fringes. The mass independence of our scheme makes it viable for a nano-object selected from an ensemble with a high mass variability. Given these advantages, a quantum superposition with a 100 nm spatial separation for a massive object of 10^{9}  amu is achievable experimentally, providing a route to test postulated modifications of quantum theory such as continuous spontaneous localization.

Voltage transfer function as an optical method to characterize electrical properties of liquid crystal devices

The voltage transfer function is a rapid and visually effective method to determine the electrical response of liquid crystal (LC) systems using optical measurements. This method relies on crosspolarized intensity measurements as a function of the frequency and amplitude of the voltage applied to the device. Coupled with a mathematical model of the device it can be used to determine the device time constants and electrical properties. We validate the method using photorefractive LC cells and determine the main time constants and the voltage dropped across the layers using a simple nonlinear filter model.

Regional review of patients with psoriatic arthritis in secondary care in the West Midlands: prevalence, disease activity and eligibility for anti-tumour necrosis factor therapy

OBJECTIVES

Tumour necrosis factor alpha-blockers (TNF-alpha) are licensed for the treatment of psoriatic arthritis (PsA) and their use has been approved by the National Institute for Health and Clinical Excellence (NICE) for use in the United Kingdom under a set of defined clinical criteria.

METHODS

In this out-patient study we evaluated PsA in rheumatology secondary care clinics in units across the West Midlands over a 2-week period, assessing prevalence, disease activity and eligibility for anti TNF-alpha treatment as defined by the NICE criteria.

RESULTS

Of the 1718 forms returned from the 2000 sent (86% response rate), 175 patients had PsA (10.2%). Of those, 22 (12.6%) were already on anti TNF-alpha treatment. 12 patients were noted to have purely axial disease and as per the NICE guidelines should not be assessed under the PsA criteria. A further 5 patients fulfilled the criteria for treatment with anti TNF-alpha with no contraindications. In the region 22 out of 27 patients (81%) with active disease were correctly on Anti TNF therapy. In total 27 (15.4%) patients with PsA met the NICE criteria for treatment of PsA with anti TNF-alpha therapy. 3 patients had previously failed anti TNF-alpha treatment. No patient fulfilling criteria for treatment were found to have any contraindications to treatment.

CONCLUSION

We note the relatively high proportion of PsA patients eligible for treatment with anti TNF-alpha blockers in the region (15.4%) compared to the NICE estimate (2.4%). This may be in part explained by a selection bias. However, the results may have significant implications for healthcare provision given the relatively high cost of anti-TNF-alpha agents. We comment on the limitations of such criteria and the effective use of regional collaboration for both training and audit purposes.

Heart rate and catecholamine contribution to QT interval shortening on exercise

BACKGROUND

QT interval shortens with exercise. Some of this shortening is due to an increase in heart rate, and some is due to other effects of exercise, probably mostly neuroendocrine effects. Data from subjects with cardiac transplants have suggested that non-heart rate-related changes in QT interval on exercise are due to the effects of circulating catecholamines.

HYPOTHESIS

We sought to determine whether changes in plasma catecholamine levels with exercise are an important contributor to non-heart rate-related QT interval shortening.

METHODS

Subjects with DDD pacemakers were recruited. Subjects had QT intervals measured at rest, during a low fixed level exercise test designed to increase heart rate to about 110 beats/min, and, after resting, during pacing at a heart rate of 110 beats/min. Catecholamine levels were measured at each stage of the study.

RESULTS

QT interval at rest was 420 +/- 12 ms, during pacing 366 +/- 16 ms, and on exercise 325 +/- 14 ms. This then gave the proportion of QT interval shortening due to heart rate as 68.6 +/- 9.3% of total QT shortening, with the range between 35 and 95.6%. There was no proportionality between the degree of QT interval shortening on exercise that was not due to increases in heart rate and changes in plasma catecholamine levels.

CONCLUSION

Two-thirds of exercise-induced QT interval shortening are due to an increase in heart rate, and one-third to other effects. Changes in plasma catecholamine levels on exercise were not closely related to changes in the QT interval on exercise.

The receptor tyrosine phosphatase Dlar and integrins organize actin filaments in the Drosophila follicular epithelium

BACKGROUND

Regulation of actin structures is instrumental in maintaining proper cytoarchitecture in many tissues. In the follicular epithelium of Drosophila ovaries, a system of actin filaments is coordinated across the basal surface of cells encircling the oocyte. These filaments have been postulated to regulate oocyte elongation; however, the molecular components that control this cytoskeletal array are not yet understood.

RESULTS

We find that the receptor tyrosine phosphatase (RPTP) Dlar and integrins are involved in organizing basal actin filaments in follicle cells. Mutations in Dlar and the common beta-integrin subunit mys cause a failure in oocyte elongation, which is correlated with a loss of proper actin filament organization. Immunolocalization shows that early in oogenesis Dlar is polarized to membranes where filaments terminate but becomes generally distributed late in development, at which time beta-integrin and Enabled specifically associate with actin filament terminals. Rescue experiments point to the early period of polar Dlar localization as critical for its function. Furthermore, clonal analysis shows that loss of Dlar or mys influences actin filament polarity in wild-type cells that surround mutant tissues, suggesting that communication between neighboring cells regulates cytoskeletal organization. Finally, we find that two integrin alpha subunits encoded by mew and if are required for proper oocyte elongation, implying that multiple components of the ECM are instructive in coordinating actin fiber polarity.

CONCLUSIONS

Dlar cooperates with integrins to coordinate actin filaments at the basal surface of the follicular epithelium. To our knowledge, this is the first direct demonstration of an RPTP's influence on the actin cytoskeleton.

The Trio family of guanine-nucleotide-exchange factors: regulators of axon guidance

Axon guidance requires the integration of diverse guidance signals presented by numerous extracellular cues and cell-cell interactions. The molecular mechanisms that interpret these signals involve networks of intracellular signaling proteins that coordinate a variety of responses to the environment, including remodeling and assembly of the actin cytoskeleton. Although it has been clear for some time that Rho family GTPases play a central role in the orchestration of cytoskeletal assembly, our understanding of the components that regulate these important molecules is far more primitive. Recent functional studies of the Trio family of guanine-nucleotide-exchange factors reveal that Trio proteins play a vital role in neuronal cell migration and axon guidance. Although the molecular analysis of Trio proteins is still in its infancy, accumulated evidence suggests that Trio proteins function as integrators of multiple upstream inputs and as activators of multiple downstream pathways. Future studies of these mechanisms promise to yield insights not only into neural development but also into the ongoing function and remodeling of the adult nervous system.

The guanine nucleotide exchange factor trio mediates axonal development in the Drosophila embryo

Recent analysis of Rho subfamily GTPases in Drosophila revealed roles for Rac and Cdc42 during axonogenesis. Here, we describe the identification and characterization of the Drosophila counterpart of Trio, a guanine nucleotide exchange factor (GEF) that associates with the receptor phosphatase LAR and regulates GTPase activation in vertebrate cells. Mutants deficient in trio activity display defects in both central and peripheral axon pathways reminiscent of phenotypes observed in embryos deficient in small GTPase function. Double mutant analysis shows that trio interacts with Rac in a dose-sensitive manner but not with Rho. Moreover, reduction of trio activity potentiates the phenotype of mutations in the LAR homolog Dlar, suggesting that these proteins collaborate in orchestrating the cytoskeletal events that underlie normal axonogenesis.

The tyrosine kinase Abl and its substrate enabled collaborate with the receptor phosphatase Dlar to control motor axon guidance

Genetic analysis of growth cone guidance choice points in Drosophila identified neuronal receptor protein tyrosine phosphatases (RPTPs) as key determinants of axon pathfinding behavior. We now demonstrate that the Drosophila Abl tyrosine kinase functions in the intersegmental nerve b (ISNb) motor choice point pathway as an antagonist of the RPTP Dlar. The function of Abl in this pathway is dependent on an intact catalytic domain. We also show that the Abl phosphoprotein substrate Enabled (Ena) is required for choice point navigation. Both Abl and Ena proteins associate with the Dlar cytoplasmic domain and serve as substrates for Dlar in vitro, suggesting that they play a direct role in the Dlar pathway. These data suggest that Dlar, Abl, and Ena define a phosphorylation state-dependent switch that controls growth cone behavior by transmitting signals at the cell surface to the actin cytoskeleton.

Clinical audit of the process of referral to genitourinary medicine of patients found to be chlamydia positive in a family planning service

This paper describes a collaborative audit between a large family planning and genitourinary medicine (GUM) service undertaken to ensure that all women presenting for termination of pregnancy (TOP) or IUD fitting were offered screening for chlamydia, were informed of a positive result, and were subsequently referred to GUM for full sexual health screening and contact tracing. Over a six month period in 1996 1072 patients were seen for either TOP (763) or W1) fitting (309) and of these 999 were offered a test which was performed in 988. Overall 38 positive tests were reported (3.8 per cent) but only two of 259 patients tested prior to lUD fitting were found to have chlamydia (<0.8 per cent). Only 27 of these 38 women (74 per cent) had information recorded in their notes that they had been given their result and 24 patients (63 per cent) were seen in GUM. The audit uncovered problems with documentation and cross-referencing of information which largely accounted for the failure to reach some of the standards set. An action plan has been formulated in an attempt to improve this aspect of the screening service. If more widespread screening for chlamydia is to be effectively implemented as recommended by the 31st RCOG Study Group on the Prevention of Pelvic Infection, then it is of importance that workable local protocols are in place including arrangements for partner notification and treatment. This will involve close collaboration between a range of specialities working in the sexual health field.

Human cells unable to express decoron produced disorganized extracellular matrix lacking "shape modules" (interfibrillar proteoglycan bridges)

The shapes of extracellular matrices are determined by positioning collagen fibrils in the right places, oriented and maintained viv-à-vis each other. The fibrils are linked orthogonally by dermatan/chondroitin sulfates or keratan sulfate (in small proteoglycans) attached every approximately 65 nm via their protein moieties to collagen fibrils at specific binding sites. These regular repeating structures are the "shape modules." The characteristic arrays of orthogonal interfibrillar bridges were missing and the extracellular matrix was totally disorganized in matrices produced by fibroblasts taken postmortem from skin of an electively aborted fetus which did not express decoron in culture, thus supporting the shape module hypothesis. Biglycon, dermatan sulfate, heparan sulfate, collagen, and hyaluronan were produced by these cells but did not contribute to a normal extracellular matrix. A similar electron histochemical and biochemical survey of extracellular matrices produced by seven normal and eight osteogenesis imperfecta cell lines from donors of different ages and both sexes showed no comparable disruptions of their matrices. This investigation appears to be the first to demonstrate systematically proteoglycan:collagen interactions in matrices produced by cultured human cells.

Possible toxicity of herbal remedies

Herbal remedies are rapidly gaining popularity throughout the world as a result of dissatisfaction with conventional medicines. It is a widely held belief that herbal preparations are "natural" and are therefore intrinsically harmless. However, their effects can be very powerful and potentially lethal if used incorrectly and their use as a substitute for conventional medicines may be ineffective. Toxic effects have been attributed to several factors including hepatotoxicity of main constituents, contamination of preparations by heavy metals or microorganisms, and adverse reactions due to age, and genetic and concomitant disease characteristics of the user.

Protistan communities in aquifers: a review

Eukaryotic microorganisms (protists) are a very important component of microbial communities inhabiting groundwater aquifers. This is not unexpected when one considers that many protists feed heterotrophically, by means of either phagotrophy (bacterivory) or osmotrophy. Protistan numbers are usually low (< 10(2) per g dw of aquifer material) in pristine, uncontaminated aquifers but may increase by several orders of magnitude in aquifers subject to organic pollution. Small flagellates (typically 2-3(5) microns in size in situ) are by far the dominant protists in aquifers, although amoebae and occasionally ciliates may also be present in much lower numbers. Although a wealth of new taxonomic information is waiting to be brought to light, interest in the identity of aquifer protists is not exclusively academic. If verified, the following hypotheses may prove to be important towards our understanding of the functioning of microbial communities in aquifers: (1) Differences in swimming behavior between species of flagellates lead to feeding heterogeneity and niche differentiation, implying that bacterivorous flagellates graze on different subsets of the bacterial community, and therefore play different roles in controlling bacterial densities. (2) Bacterivorous flagellates grazing on bacteria capable of degrading organic compounds have an indirect effect on the overall rates of biodegradation.

Gingival fibromatosis and Klippel-Trénaunay-Weber syndrome. Case report

A case of a young male with the Klippel-Trénaunay-Weber syndrome is described. Typical features of hemihypertrophy, hemangiomata, macrodactyly, and macrocephaly were present. The most striking oral feature was generalized severe gingival hypertrophy confirmed histologically, ultrastructurally, and by collagen analysis. In the absence of other known systemic causes of gingival enlargement, a diagnosis of familial gingival fibromatosis in association with Klippel-Trénaunay-Weber-syndrome is concluded. The combination of gingival fibromatosis and Klippel-Trénaunay-Weber syndrome has not been reported to our knowledge, it is uncertain whether this occurrence is significant or coincidental.

Apoprotein B-100 production is decreased in subjects heterozygous for truncations of apoprotein B

Among individuals who are heterozygous for familial hypobetalipoproteinemia (FHBL) and who have various truncations of apoprotein (apo) B (ie, FHBL with apoB truncation/apoB-100 genotypes), the plasma concentrations of apoB-100 are typically approximately 30% rather than the expected approximately 50% of those in unaffected family members. The metabolic basis for the low apoB-100 levels is unknown. Therefore, we compared the metabolism of apoB-100 in 8 subjects with heterozygous FHBL (2 apoB-89/apoB-100, 2 apoB-75/apoB-100, 2 apoB-54.8/apoB-100, 1 apoB-52/apoB-100, and 1 apoB-31/apoB-100) with the metabolism of apoB-100 in 8 apoB-100/apoB-100 control subjects who were paired with the heterozygotes by gender, age, height, weight, and race. Endogenous labeling of apoB-100 with [13C]leucine and a multicompartmental kinetic model were used to obtain kinetic parameters. FHBL heterozygotes had significantly reduced VLDL apoB-100 production rates (7.7 +/- 3.7 versus 21.2 +/- 6.2 mg.kg-1.d-1, P = .002) and LDL apoB-100 production rates (4.5 +/- 3.12 versus 15.3 +/- 1 mg.kg-1.d-1, P = .05) compared with control subjects. Fractional conversion rates of VLDL to LDL were not significantly different (0.67 +/- 0.36 versus 0.77 +/- 0.17 pools/d), and the respective fractional catabolic rates of apoB-100 in VLDL, IDL, and LDL also were similar in both groups. Thus, FHBL heterozygotes produced apoB-100 at about 30% of the rates of control subjects. We believe these reduced production rates largely account for the lower than expected levels of apoB-100 and LDL cholesterol in the plasma of FHBL heterozygotes.

QT interval dispersion in chronic heart failure and left ventricular hypertrophy: relation to autonomic nervous system and Holter tape abnormalities

OBJECTIVE

To study QT dispersion in left ventricular hypertrophy and chronic heart failure and to determine the relation to ventricular arrhythmias.

SETTING

Investigational laboratory of a tertiary referral centre.

STUDY DESIGN

Patients with left ventricular hypertrophy and normal systolic function (n = 14) and patients with chronic heart failure (n = 18) were matched with controls (n = 17). The QT dispersion was examined in relation to abnormalities in resting mechanical and autonomic function and to the findings of 24 hour Holter monitoring.

MAIN OUTCOME MEASURES

QT dispersion is the difference between the maximum and the minimum QT values from the 12 lead electrocardiogram. Mean(SD) QT dispersion from the 10 lead electrocardiogram was also examined once the 12 lead minimum and maximum values had been removed. The QT distribution is the curve describing the distance from the mean for all QT intervals (ms).

RESULTS

All measures of QT dispersion were increased significantly in left ventricular hypertrophy and tended to increase in those with heart failure. The QT distribution was abnormal in both heart failure and left ventricular hypertrophy. There was no relation between the degree of change in QT dispersion and the incidence of ventricular arrhythmia on 24 hour Holter monitoring. Also there was no relation between QT dispersion and autonomic or mechanical abnormalities. The QT dispersion was related to QRS duration.

CONCLUSION

Though QT dispersion and distribution are abnormal in left ventricular hypertrophy these findings do not support the hypothesis that QT dispersion reflects arrhythmic risk in either hypertrophy or heart failure.

Efficacy of psyllium in reducing serum cholesterol levels in hypercholesterolemic patients on high- or low-fat diets

OBJECTIVES

To determine the efficacy of psyllium in reducing serum cholesterol levels in patients on high- or low-fat diets.

DESIGN

Double-blind, placebo-controlled, 16-week parallel trial. The study included an 8-week baseline period and an 8-week treatment period.

PATIENTS

Healthy men and women, 21 to 70 years old, with primary hypercholesterolemia (total serum cholesterol > or = 5.7 mmol/L [220 mg/dL]). Thirty-seven participants followed a high-fat diet and 81 participants followed a low-fat diet.

INTERVENTION

Participants were randomly assigned to either psyllium, 5.1 g twice a day, or placebo.

MEASUREMENTS

Fasting lipid and apolipoprotein concentrations, including direct low-density lipoprotein (LDL) cholesterol quantification; nutritional analyses of 4 days of 7-day food records to monitor dietary compliance; and physical examinations, clinical chemistry and hematologic studies, and urinalysis to assess treatment safety.

MAIN RESULTS

Psyllium recipients in both the high- and low-fat diet groups showed small but significant decreases (P < 0.05) in total cholesterol and low-density lipoprotein (LDL) cholesterol levels. Total cholesterol and LDL cholesterol levels decreased 5.8% and 7.2%, respectively, in psyllium recipients on high-fat diets and 4.2% and 6.4%, respectively, in psyllium recipients on low-fat diets. No significant difference was seen in LDL cholesterol response when psyllium recipients on low- and high-fat diets were compared (P > 0.2). No significant reductions in lipid levels were observed in placebo recipients. Based on the National Cholesterol Education Program LDL cholesterol classification system, 39% of the psyllium recipients improved in LDL cholesterol classification (P < 0.0001) compared with 20.3% of placebo recipients (P > 0.2).

CONCLUSIONS

Psyllium produces a modest but significant improvement in total cholesterol and LDL cholesterol levels in persons on either low-fat or high-fat diets. Psyllium, when added to a prescribed low-fat diet, may obviate the need for typical lipid-lowering medications or may prove to be a valuable adjunct to other treatments in patients with moderately elevated LDL cholesterol levels.

Neutrophil integrin assay for clinical studies

The level of expression of neutrophil adhesion molecules may be a useful marker for neutrophil activation in clinical studies. We therefore determined neutrophil integrin expression under various experimental conditions using a Fluorescence Activated Cell Sorter (FACS) after the cells had been labelled with fluorescent conjugated antibodies to the integrin subunits CD11a, CD11b and CD18. Levels of labelled CD11b and CD18 increased after activation with the chemotactic peptide formyl-methionyl-leucyl phenylalanine (fMLP) in a dose- and time-dependent manner, but CD11a did not, indicating that CD11a would not be a useful marker of neutrophil activation. The baseline expression of CD11b and CD18 on unstimulated neutrophils was similar in heparin and EDTA anti-coagulated blood but the response to activation with fMLP was significantly less for the EDTA anti-coagulated samples (p < 0.01 in paired t-test). The labelling of integrins was significantly higher in unfixed whole blood samples compared to samples fixed with 1 per cent paraformaldehyde. However, the increase in labelling induced by fMLP was similar whether or not the samples were fixed after activation. Labelling of CD11b and CD18 was greater for preparations of isolated neutrophils than for neutrophils in whole blood, and the response to fMLP stimulation tended to be lower for the isolated cells. Our results indicate that heparin should be used as anti-coagulant in clinical studies utilizing whole blood if subsequent activation of neutrophils is planned (e.g. to detect in vivo priming), although EDTA may be used if baseline expression alone is to be measured. Fixation of blood samples should not affect the ability to detect neutrophil activation.

Pyogenic liver abscess: a 7-year experience in a large community hospital

This is a retrospective study of 27 consecutive patients with a diagnosis of pyogenic liver abscess (PLA) seen over a period of 7 years. There were 10 males and 17 females whose ages ranged from 5 to 86 years (mean 56). Fever, abdominal pain and vomiting were the commonest symptoms, and abdominal tenderness was the commonest physical finding. An elevated alkaline phosphatase was seen in 78% of all patients and was the commonest biochemical abnormality. Biliary disease accounted for a third of all cases, and in 22% of the patients the abscesses were considered to be idiopathic. Ultrasonography and/or CT scanning was employed in the diagnosis and follow-up of all patients. Percutaneous needle aspiration (PNA) and percutaneous drainage (PCD) under ultrasound or CT guidance was employed as the primary therapy in 24 patients. The procedure failed in 5 patients (18.5%), there was 1 complication (3.7%) and no deaths were seen as a result of these procedures. Three patients (11%) ultimately died of their abscesses. This study emphasizes the important role of percutaneous drainage as a complementary form of therapy to surgical drainage in the management of pyogenic liver abscesses.

A high carbohydrate-fat free diet alters the proportion of heparin-bound VLDL in plasma and the expression of VLDL-apoB-100 epitopes

High carbohydrate-fat free diets (CHO-diet) induce the secretion of increased numbers of very-low-density lipoprotein (VLDL) particles and alter the composition and metabolism of VLDL. The aims of this study were to examine VLDL in greater detail, specifically to document any CHO-diet-induced alterations of apolipoprotein B-100 (apoB-100) epitope expression of VLDL, and any changes induced in subclasses of VLDL, as defined by heparin Sepharose chromatography. Fifteen normolipidemic subjects participated in the study by eating a basal typical American diet for 7 days and high carbohydrate diet (85% carbohydrate, less than 1% fat) for another 7 days. The sequence was changed in seven subjects. Fasting blood samples were analyzed for lipoprotein lipid and apoprotein concentrations. Heparin affinity VLDL subclasses were characterized chemically and electrophoretically [sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE)]. Immunoreactivities of apoB in VLDL were tested in solid phase competitive-binding radioimmunoassays (RIAs) using five monoclonal anti-B antibodies that react with defined epitopes of apoB-100. The CHO diet produced consistent increases of plasma triglycerides in all subjects by a mean of 66% and decreases in plasma cholesterol by 18%. ApoB in plasma decreased by 21% and apoA-I by 17%; however, apoE and ApoA-II did not change. VLDL was enriched with triglycerides (55.0% +/- 0.8 v 57.0% +/- 0.7, P less than .05) and apoE (3.7% +/- 0.5 to 5.9% +/- 0.7, P less than .007) and the ratio between apoE and apoC in VLDL increased (0.15 +/- 0.03 to 0.25 +/- 0.03, P less than .002).(ABSTRACT TRUNCATED AT 250 WORDS)

An extra source of conflict? Diabetes in adolescence

Adolescence can be difficult at the best of times, but being diabetic can add extra stress. Nurses can minimise this by supporting diabetic adolescents and helping them lead as normal lives as possible.

High carbohydrate fat-free diet modulates epitope expression of LDL-apoB-100 and interaction of LDL with human fibroblasts

High carbohydrate diets are known to increase the concentration of very low density lipoprotein (VLDL) and to lower the concentrations of low density lipoprotein (LDL) and high density lipoprotein (HDL) in plasma. Such diets also alter lipoprotein compositions and metabolism. The aims of the present study were to assess in detail the effects of a virtually fat-free high carbohydrate (CHO) diet (CHO greater than 85% and fat less than 1% of calories) on various aspects of LDL. Thirteen healthy normolipidemic volunteers ate a basal "American" diet and the CHO diet for 7 days each in a forward or reverse sequence. Fasting blood samples were drawn at the ends of each study period and analyzed for lipoprotein lipid and apolipoprotein concentrations. Compositions of LDL particles isolated by ultracentrifugation were characterized chemically, LDL sizes were assessed by nondenaturing gradient electrophoresis on 2-16% gels, and association and degradation of LDL with normal human skin fibroblasts were quantified in cell cultures. Immunoreactivities of apoB in LDL were tested in solid phase competitive binding radioimmunoassays using five monoclonal anti-LDL antibodies that reacted with defined epitopes of apoB-100. The study diet produced consistent decreases of LDL cholesterol and apoB concentrations by 25% and 17%, respectively. LDL compositions were altered. Mean LDL triglycerides increased 3% to 4% of total LDL mass (P less than 0.004), and LDL particle sizes decreased (P less than 0.01). In radioimmunoassays that contained monoclonal antibody B1B3, an antibody that inhibits binding of LDL to the LDL receptor, the mean ED50 value for LDL protein was reduced from 3.75 to 2.66 micrograms (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation of clinical and molecular biological abnormalities in osteogenesis imperfecta

Substitution of a glycine residue in the triple helix of the alpha 1(I) chain by either arginine, valine or alanine was associated with the type II lethal perinatal osteogenesis imperfecta phenotype. This phenotype was also produced by a frameshift mutation that resulted in an abnormal amino acid sequence of the carboxy-terminal propeptide of the pro-alpha 1(I) chain. The latter baby, however, showed some clinical and radiographic differences from the other babies with type II OI. The severity of the clinical and radiographic phenotypes are likely to be determined by both the type and site of the mutation as well as by the intra-uterine environment.

Uncoupled expression of mRNAs for alpha 1(I) and alpha 2(I) procollagen chains in chemically transformed Syrian hamster fibroblasts

Syrian hamster embryo fibroblasts transformed by 4-nitroquinoline-1-oxide (NQT-SHE cells) failed to synthesize the pro-alpha 1(I) subunit of type I procollagen but continued to synthesize altered forms of the other subunit, pro-alpha 2(I) (Peterkofsky, B., and Prather, W. (1986) J. Biol. Chem. 261, 16818-16826). This was unusual, since synthesis of the two subunits generally is coordinately regulated. Present experiments using cell-free translation and hybridization of RNA from normal and transformed Syrian hamster fibroblasts with labeled pro-alpha 1(I) DNA probes show that mRNA for pro-alpha 1(I) is absent from the transformant. In contrast, dot-blot and Southern blot hybridizations of cellular DNAs with pro-alpha 1(I) DNA probes demonstrated that the transformed cells contained pro-alpha 1(I) gene sequences and that the gross structure of the gene was unchanged by transformation. mRNA for the other type I procollagen subunit, pro-alpha 2(I), was present in transformed cells and the major collagenous polypeptide translated from this RNA migrated like the normal pro-alpha 2 subunit during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The translated procollagen chain was cleaved to an alpha 2(I)-sized collagen chain by pepsin at 4 degrees C. These studies provide a molecular basis for the observed collagen phenotype of NQT-SHE cells.

Perinatal lethal osteogenesis imperfecta in transgenic mice bearing an engineered mutant pro-alpha 1(I) collagen gene

Substitutions of single glycine residues of alpha 1(I) collagen have previously been associated with the inherited disease osteogenesis imperfecta type II. Transgenic mice bearing a mutant alpha 1(I) collagen gene into which specific glycine substitutions have been engineered show a dominant lethal phenotype characteristic of the human disease, and demonstrate that as little as 10% mutant gene expression can disrupt normal collagen function.

Introduction of the human pro alpha 1(I) collagen gene into pro alpha 1(I)-deficient Mov-13 mouse cells leads to formation of functional mouse-human hybrid type I collagen

The Mov-13 mouse strain carries a retroviral insertion in the pro alpha 1(I) collagen gene that prevents transcription of the gene. Cell lines derived from homozygous embryos do not express type I collagen although normal amounts of pro alpha 2 mRNA are synthesized. We have introduced genomic clones of either the human or mouse pro alpha 1(I) collagen gene into homozygous cell lines to assess whether the human or mouse pro alpha 1(I) chains can associate with the endogenous mouse pro alpha 2(I) chain to form stable type I collagen. The human gene under control of the simian virus 40 promoter was efficiently transcribed in the transfected cells. Protein analyses revealed that stable heterotrimers consisting of two human alpha 1 chains and one mouse alpha 2 chain were formed and that type I collagen was secreted by the transfected cells at normal rates. However, the electrophoretic migration of both alpha 1(I) and alpha 2(I) chains in the human-mouse hybrid molecules were retarded, compared to the alpha (I) chains in control mouse cells. Inhibition of the posttranslational hydroxylation of lysine and proline resulted in comigration of human and mouse alpha 1 and alpha 2 chains, suggesting that increased posttranslational modification caused the altered electrophoretic migration in the human-mouse hybrid molecules. Amino acid sequence differences between the mouse and human alpha chains may interfere with the normal rate of helix formation and increase the degree of posttranslational modifications similar to those observed in patients with lethal perinatal osteogenesis imperfecta. The Mov-13 mouse system should allow us to study the effect specific mutations introduced in transfected pro alpha 1(I) genes have on the synthesis, assembly, and function of collagen I.

Phospholipid asymmetry in human erythrocyte ghosts

Using phospholipase digestion and the fluorescent probe merocyanine 540 the maintenance of phospholipid asymmetry in the plasma membrane of human erythrocyte ghosts was investigated. Digestion with phospholipase A2 indicated that ghosts prepared in the presence of Mg++ as the only divalent cation retained the normal phospholipid asymmetry characteristic of intact erythrocytes. These ghosts, like normal erythrocytes, also failed to stain with merocyanine 540. However, the presence of as little as 5-10 microM Ca++ during ghost preparation resulted in ghosts in which lipid asymmetry had been abolished, as indicated by phospholipase digestion. Moreover, these ghosts stained with merocyanine 540. In contrast to ghosts, intact erythrocytes treated with ionophore required millimolar levels of Ca++ ions to disrupt membrane lipid asymmetry. To discover the reason for this difference in behavior between ghosts and intact cells, ghosts were prepared from preswollen cells using only small volumes of buffer for lysis. These experiments demonstrated that as the cellular contents of erythrocytes are diluted, the asymmetric arrangement of phospholipids becomes more sensitive to disruption by Ca++.

Immunohistochemical localization of carcinoembryonic antigen (CEA), CEA-S, and nonspecific cross-reacting antigen (NCA) in carcinomas of lung

Antisera to carcinoembryonic antigen (CEA), to a physicochemical subset of CEA, namely CEA-S, and to nonspecific cross-reacting antigen (NCA) were used for the immunohistochemical localization of these antigens in human bronchogenic carcinomas using a triple layer immunoperoxidase technique. The study is based on an analysis of tumors from 130 patients. CEA, CEA-S, and NCA were all identified in the membrane and/or cytoplasm of neoplastic cells, and a good correlation between the antigens was observed in a majority of tumors. The presence or absence of these tumor-associated glycoproteins appeared to be correlated with the histologic type of the tumors, especially in small cell anaplastic carcinoma and adenocarcinoma, and the degree of histologic differentiation of adenocarcinomas correlated positively with these tumor-associated antigens. Data from this group of patients suggest that analysis of tissue CEA at the time of biopsy or surgical resection may facilitate a more objective interpretation of serial plasma CEA assays.

Inhibition by tumor-promoting phorbol esters of procollagen synthesis in promotable JB6 mouse epidermal cells

The JB6 mouse epidermal cell line has been developed to study promotion of neoplastic transformation in vitro. Treatment of JB6 cells with 12-O-tetradecanoylphorbol 13-acetate (TPA) or other tumor promoters resulted in the irreversible acquisition by JB6 cells of tumorigenicity in nude mice and anchorage-independent growth in soft agar. As previously reported, one of the biochemical responses that occurs during TPA treatment is a greater than 75% reduction in a mannose-labeled glycoprotein with an apparent molecular weight of 180,000. This TPA-sensitive glycoprotein has now been identified on the basis of collagenase and pepsin sensitivity as procollagen pro-alpha 1(I) chain. [3H]proline labeling also demonstrated a parallel decrease in the 150,000 procollagen pro-alpha 2(I) component. Two nonphorbol promoters, mezerein and epidermal growth factor, were also active in decreasing procollagen synthesis. Promotion-sensitive and promotion-resistant clonal derivatives of JB6 showed similar basal levels of collagen synthesis as well as similar degrees of TPA-dependent procollagen loss indicating that the collagen decrease may be necessary but is not sufficient to produce the promotion response. Comparison of chemically transformed mouse epidermal cell lines with paried nontransformants suggests the reduced procollagen synthesis is a stably acquired phenotypic change and may therefore be involved in maintenance of the transformed phenotype as well as in its induction.

Involvement of spectrin in the maintenance of phase-state asymmetry in the erythrocyte membrane

The fluorescent probe merocyanine 540 does not stain the plasma membrane of normal human or murine erythrocytes, nor of genetically abnormal human spherocytic erythrocytes. It does, however, stain erythrocyte membranes in several systems in which the underlying spectrin network is altered or missing. Because of the greater affinity of merocyanine 540 for fluid--phase lipid bilayers, these results suggest that the external leaflet of erythrocyte membranes becomes more disordered upon alteration or loss of the internal spectrin network. Analysis of the transbilayer arrangement of membrane phospholipids by digestion with phospholipase A2 suggests that lipid compositional asymmetry of the erythrocyte membrane is responsible for a phase-state asymmetry between the two lipid leaflets, and that spectrin is required to maintain this asymmetry and the gel-like state of the external leaflet.

Therapy of locally unresectable pancreatic carcinoma: a randomized comparison of high dose (6000 rads) radiation alone, moderate dose radiation (4000 rads + 5-fluorouracil), and high dose radiation + 5-fluorouracil: The Gastrointestinal Tumor Study Group

One-hundred-ninety-four eligible and evaluable patients with histologically confirmed locally unresectable adenocarcinoma of the pancreas were randomly assigned to therapy with high-dose (6000 rads) radiation therapy alone, to moderate-dose (4000 rads) radiation + 5-fluorouracil (5-FU), and to high-dose radiation plus 5-FU. Median survival with radiation alone was only 51/2 months from date of diagnosis. Both 5-FU-containing treatment regimens produced a highly significant survival improvement when compared with radiation alone. Forty percent of patients treated with the combined regimens were still living at one year compared with 10% of patients treated with radiation only. Survival differences between 4000 rads plus 5-FU and 6000 rads plus 5-FU were not significant with an overall median survival of ten months. Significant prognostic variables, in addition to treatment, were pretreatment performance status and pretreatment CEA level.

Therapy of locally unresectable pancreatic carcinoma: a randomized comparison of high dose (6000 rads) radiation alone, moderate dose radiation (4000 rads + 5-fluorouracil), and high dose radiation + 5-fluorouracil: The Gastrointestinal Tumor Study Group

One-hundred-ninety-four eligible and evaluable patients with histologically confirmed locally unresectable adenocarcinoma of the pancreas were randomly assigned to therapy with high-dose (6000 rads) radiation therapy alone, to moderate-dose (4000 rads) radiation + 5-fluorouracil (5-FU), and to high-dose radiation plus 5-FU. Median survival with radiation alone was only 51/2 months from date of diagnosis. Both 5-FU-containing treatment regimens produced a highly significant survival improvement when compared with radiation alone. Forty percent of patients treated with the combined regimens were still living at one year compared with 10% of patients treated with radiation only. Survival differences between 4000 rads plus 5-FU and 6000 rads plus 5-FU were not significant with an overall median survival of ten months. Significant prognostic variables, in addition to treatment, were pretreatment performance status and pretreatment CEA level.