A multicentre audit of GDPs knowledge of orthodontic retention

OBJECTIVE

To determine GDP knowledge and willingness to supervise orthodontic retention and provide replacements retainers.

DESIGN

An audit sampling GDPs from six centres within England (Bradford, Cambridge, Burton-Upon-Trent, Croyden, Norwich and Plymouth). A gold standard of 100% of GDPs should be aware of commonly used retainers and be able to provide replacements was selected.

METHOD

Overall, 1,053 postal questionnaires were sent to local GDPs. The questions covered knowledge and provision of various retainers, practitioner background and education. GDP satisfaction with the information provided by the orthodontist at discharge was also explored.

RESULTS

Five hundred and two questionnaires were received (response rate of 48%). The majority of GDPs (64%) were trained in the UK. Awareness of vacuum-formed, Hawley and fixed retainers was generally high. A significantly smaller number of GDPs were willing to prescribe, fit or review the retainers. The most common reasons for reluctance in provision were insufficient knowledge, financial and time constraints. Over two thirds (72%) of GDPs would like further training on retention.

CONCLUSION

This audit highlights a need for increased training at undergraduate and postgraduate levels to update practitioners about contemporary retention practice. Better communication is required from orthodontists to GDPs to ensure that on discharge the dentist is aware of the retainer type and retention regime.

Performance monitoring for brain-computer-interface actions

When presented with a difficult perceptual decision, human observers are able to make metacognitive judgements of subjective certainty. Such judgements can be made independently of and prior to any overt response to a sensory stimulus, presumably via internal monitoring. Retrospective judgements about one's own task performance, on the other hand, require first that the subject perform a task and thus could potentially be made based on motor processes, proprioceptive, and other sensory feedback rather than internal monitoring. With this dichotomy in mind, we set out to study performance monitoring using a brain-computer interface (BCI), with which subjects could voluntarily perform an action - moving a cursor on a computer screen - without any movement of the body, and thus without somatosensory feedback. Real-time visual feedback was available to subjects during training, but not during the experiment where the true final position of the cursor was only revealed after the subject had estimated where s/he thought it had ended up after 6s of BCI-based cursor control. During the first half of the experiment subjects based their assessments primarily on the prior probability of the end position of the cursor on previous trials. However, during the second half of the experiment subjects' judgements moved significantly closer to the true end position of the cursor, and away from the prior. This suggests that subjects can monitor task performance when the task is performed without overt movement of the body.

Oscillatory neural responses evoked by natural vestibular stimuli in humans

While there have been numerous studies of the vestibular system in mammals, less is known about the brain mechanisms of vestibular processing in humans. In particular, of the studies that have been carried out in humans over the last 30 years, none has investigated how vestibular stimulation (VS) affects cortical oscillations. Here we recorded high-density electroencephalography (EEG) in healthy human subjects and a group of bilateral vestibular loss patients (BVPs) undergoing transient and constant-velocity passive whole body yaw rotations, focusing our analyses on the modulation of cortical oscillations in response to natural VS. The present approach overcame significant technical challenges associated with combining natural VS with human electrophysiology and reveals that both transient and constant-velocity VS are associated with a prominent suppression of alpha power (8-13 Hz). Alpha band suppression was localized over bilateral temporo-parietal scalp regions, and these alpha modulations were significantly smaller in BVPs. We propose that suppression of oscillations in the alpha band over temporo-parietal scalp regions reflects cortical vestibular processing, potentially comparable with alpha and mu oscillations in the visual and sensorimotor systems, respectively, opening the door to the investigation of human cortical processing under various experimental conditions during natural VS.

Learning to integrate contradictory multisensory self-motion cue pairings

Humans integrate multisensory information to reduce perceptual uncertainty when perceiving the world and self. Integration fails, however, if a common causality is not attributed to the sensory signals, as would occur in conditions of spatiotemporal discrepancies. In the case of passive self-motion, visual and vestibular cues are integrated according to statistical optimality, yet the extent of cue conflicts that do not compromise this optimality is currently underexplored. Here, we investigate whether human subjects can learn to integrate two arbitrary, but co-occurring, visual and vestibular cues of self-motion. Participants made size comparisons between two successive whole-body rotations using only visual, only vestibular, and both modalities together. The vestibular stimulus provided a yaw self-rotation cue, the visual a roll (Experiment 1) or pitch (Experiment 2) rotation cue. Experimentally measured thresholds in the bimodal condition were compared with theoretical predictions derived from the single-cue thresholds. Our results show that human subjects combine and optimally integrate vestibular and visual information, each signaling self-motion around a different rotation axis (yaw vs. roll and yaw vs. pitch). This finding suggests that the experience of two temporally co-occurring but spatially unrelated self-motion cues leads to inferring a common cause for these two initially unrelated sources of information about self-motion. We discuss our results in terms of specific task demands, cross-modal adaptation, and spatial compatibility. The importance of these results for the understanding of bodily illusions is also discussed.

A life cycle model to enable research of cryostorage recalcitrance in temperate woody species: the case of sitka spruce (Picea sitchensis)

Empirical testing of protocols and fundamental investigations are the approaches usually applied to study germplasm storage recalcitrance in temperate plants. However, they can fall short of practicable solutions, even after exhaustive experimentation, and the generation of negative survival data makes it difficult to plan further investigations. Picea sitchensis somatic embryos are amenable to cryopreservation whereas in vitro shoot meristems, although able to survive, are incapable of sustained recovery. Differential Scanning Calorimetry (DSC) revealed that these disparate responses could not be attributed to biophysical factors. A model is presented hypothesising that in some cases life cycle adaptations (cold hardening, dormancy) may have opposing influences on survival causing delayed-onset, cryogenically-induced loss of viability in temperate tree species.

Self-motion leads to mandatory cue fusion across sensory modalities

When perceiving properties of the world, we effortlessly combine multiple sensory cues into optimal estimates. Estimates derived from the individual cues are generally retained once the multisensory estimate is produced and discarded only if the cues stem from the same sensory modality (i.e., mandatory fusion). Does multisensory integration differ in that respect when the object of perception is one's own body, rather than an external variable? We quantified how humans combine visual and vestibular information for perceiving own-body rotations and specifically tested whether such idiothetic cues are subjected to mandatory fusion. Participants made extensive size comparisons between successive whole body rotations using only visual, only vestibular, and both senses together. Probabilistic descriptions of the subjects' perceptual estimates were compared with a Bayes-optimal integration model. Similarity between model predictions and experimental data echoed a statistically optimal mechanism of multisensory integration. Most importantly, size discrimination data for rotations composed of both stimuli was best accounted for by a model in which only the bimodal estimator is accessible for perceptual judgments as opposed to an independent or additive use of all three estimators (visual, vestibular, and bimodal). Indeed, subjects' thresholds for detecting two multisensory rotations as different from one another were, in pertinent cases, larger than those measured using either single-cue estimate alone. Rotations different in terms of the individual visual and vestibular inputs but quasi-identical in terms of the integrated bimodal estimate became perceptual metamers. This reveals an exceptional case of mandatory fusion of cues stemming from two different sensory modalities.

Common things are common: a case series of oral foreign bodies in paediatric patients

Reports of foreign bodies in the oral cavity are few in number. Three cases of children of varying ages, presenting with oral foreign bodies, and their subsequent diagnosis and management, are described. The importance of considering foreign bodies, as part of a differential diagnosis in paediatric patients, where aetiology is uncertain and clinical appearance is unusual, is highlighted.

Postpartum mood disorders: a review of clinical and epidemiological factors

The postpartum period is a time of risk for mood disturbance in women. Postpartum blues occurs commonly, but is self-limited. Postpartum depression occurs in 13% of postpartum women. However, it is estimated that nearly one-half of all cases go undetected. Postpartum psychosis is rare, affecting 1-2 per 1000 women. Postpartum mood disorders can have far-reaching consequences and have been shown to affect the social and psychological development of children. It is critical that healthcare providers understand these disorders and their risk factors to increase detection and to educate women about the risks and treatments of postpartum mood disorders. This review is intended to provide healthcare providers with a better understanding of the descriptive epidemiology, risk factors, and treatments of postpartum mood disorders. The utility of specific screening instruments is also discussed.

Selective modulation of chemokinesis, degranulation, and apoptosis in eosinophils through the PGD2 receptors CRTH2 and DP

BACKGROUND

PGD(2) is the major prostanoid released by mast cells during an allergic response. Its role in the allergic response, however, remains unclear.

OBJECTIVE

Because the accumulation of eosinophils is a feature of allergic reactions, we investigated the role of PGD(2) in the modulation of eosinophil function.

METHODS

Circulating human eosinophils were isolated and challenged with PGD(2). The effects of PGD(2) on various eosinophil functions were then analyzed.

RESULTS

PGD(2) binds with high affinity preferentially to 2 receptors, DP and chemoattractant receptor-homologous molecule expressed on T(H)2 cells (CRTH2). We show that both DP and CRTH2 are detectable on circulating eosinophils. We demonstrate that PGD(2) (1-10 nmol/L) induces a rapid change in human eosinophil morphology and an increase in chemokinesis and promotes eosinophil degranulation. These effects are induced by the CRTH2-selective agonist 13-14-dihydro-15-keto-PGD(2) (DK-PGD(2)) but not by the DP-selective agonist BW245C. These results suggest a role for CRTH2 in the modulation of eosinophil movement and in triggering the release of cytotoxic proteins. Finally, we demonstrate that BW245C, but not DK-PGD(2), can delay the onset of apoptosis in cultured eosinophils, presumably through interaction with DP.

CONCLUSION

These data support the hypothesis that PGD(2) controls eosinophil functions through 2 pharmacologically distinct receptors with independent functions. Blockade of PGD(2)-mediated effects on human eosinophils may reduce the damage caused by these cells during an allergic response, but inhibition of both receptors may be required.

Cataract surgery in a community hospital outreach clinic: patients' costs and satisfaction

A cataract day surgery service for the population of central Norfolk, UK, was provided by the main ophthalmic department in a district general hospital and in an outreach clinic in a community hospital 40 km distant. The outreach clinic aimed to extend the accessibility of this particular service in a rural area where many patients faced long journeys to the main hospital. Samples of 201 patients attending the main hospital for day cataract surgery and 198 patients attending the outreach clinic for the same procedure were identified. Patients were interviewed and given questionnaire forms to establish their general health before the operation, their arrangements to get to hospital and their satisfaction with the clinic and the care they had received. The sample of patients attending the outreach clinic was slightly older, less affluent and in slightly poorer general health than the patients attending the main hospital. The two samples were similar in terms of visual acuity after the operation, complication rates, satisfaction with the outcome of the operation and subsequent use of health services. The journey to hospital was quicker, more convenient and less costly for the outreach clinic patients than the main hospital patients. The net benefit to patients of the outreach clinic was estimated as pounds sterling 39,000 per annum. Satisfaction with administrative matters, facilities at the two clinics and the care received was high in both samples, but patients were significantly more satisfied with arrangements at the smaller outreach clinic. This evidence suggests that an outreach clinic in a small community hospital can provide cataract day surgery under local anaesthesia as effectively as a district centre, at a reduced social cost and with positive social benefits. Further study of heath service costs is vital, but political pressure to acknowledge patient preferences for more local services is growing.

Deprivation and poor health in rural areas: inequalities hidden by averages

Poor health and social deprivation scores in 570 wards in East Anglia, UK, were much less associated in rural than in urban areas. The deprivation measure most closely related to poor health in the least accessible rural wards was male unemployment, but use of this measure did not remove the urban-rural gradient of association strength. Neither did replacing wards by smaller enumeration districts as the units of analysis. The differences between urban and rural correlations were removed by restricting the comparison to wards with the same unemployment range and combining pairs of rural wards with similar deprivation values. Apparent differences between rural and urban associations are therefore not due to the choice of deprivation indices or census areas but are artifacts of the greater internal variability, smaller average deprivation range and smaller population size of rural small areas. Deprived people with poor health in rural areas are hidden by favourable averages of health and deprivation measures and do not benefit from resource allocations based on area values.

Mortality, long-term illness and deprivation in rural and metropolitan wards of England and Wales

The relationships between mortality, limiting long-term illness and indicators of social deprivation were investigated using regression analysis on data for rural wards, metropolitan wards and the remaining wards in England and Wales. Regional differences were controlled. In rural wards, people had better health than average and slightly better health than would be expected from their deprivation scores. Average levels of health in rural areas were only weakly related to deprivation, which was partly but not fully due to the restricted range of average deprivation values in rural wards. In metropolitan areas, relatively poor levels of health were largely explained by social deprivation, but people in Inner London were healthier than might be expected from measures of deprivation. The relationship between health and social deprivation is therefore not uniform over England and Wales, but varies between geographical types of area. One consequence is that resource allocation on the basis of social deprivation would put the populations of rural areas and Inner London at an advantage.

Autism and autistic behavior in Joubert syndrome

To determine whether individuals with Joubert syndrome exhibit features of autism as defined by the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV), we examined 11 children with Joubert syndrome using the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule-Generic. Three children met DSM-IV criteria for autistic disorder and one for pervasive developmental disorder not otherwise specified. The other seven all demonstrated at least one DSM-IV symptom of autism, but did not meet criteria for a pervasive developmental disorder. Both total number of DSM-IV symptoms and number of social symptoms distinguished the autism and nonautism subgroups. In contrast, the two subgroups displayed similar levels of communication impairments and repetitive or stereotyped behavior. The key to diagnosing autism in Joubert syndrome is to focus on social behaviors, particularly milestones typically achieved very early in life (eg, attending to human voices, showing objects of interest, enjoyment of social interactions). Implications for the role of the cerebellum in nonmotor behavior and for clinical management of Joubert syndrome also are discussed.

Effects of distances to hospital and GP surgery on hospital inpatient episodes, controlling for needs and provision

Age and sex adjusted inpatient episode ratios were calculated from hospital records over a two year period for 555 census wards in Cambridgeshire, Norfolk and Suffolk, UK. Hospital episodes were divided into acute, psychiatric and geriatric specialties, and elective and emergency acute admissions were distinguished. Variations in inpatient episode ratios between wards were compared with census indicators of the 'needs' of local populations for inpatient services, measures of the local provision of hospital and other related services, and measures of the distance to the nearest general practitioner surgery and the distance to the nearest hospital. Hospital episodes were found to be strongly related to both distance measures, but the associations were partially explained by a tendency for the health status of local populations (measured by the needs indicators) to be worst in urban areas close to health services. Including needs and provision variables together with the distance variables explained most of the variations in age and sex adjusted inpatient ratios for small areas. Needs were the most important determinants of emergency acute and psychiatric inpatient rates, but service provision was more important for elective acute and geriatric inpatients. Controlling for needs and provision, distance to hospital produced 17% reduction in acute episodes, 37% reduction in psychiatric episodes and 23% reduction in geriatric episodes over the range of distances observed. Distance to nearest GP surgery reduced elective acute episodes by up to 15% after controlling for confounders. These results demonstrate that the NHS is falling short of its aim to provide fair access to services irrespective of geography, and new policies will be required if geographical inequities are to be reduced.

Factors associated with home advantage in English and Scottish soccer matches

Using the results from the end-of-season (1992-93) league tables, overall home advantage was confirmed in the eight major divisions of the English and Scottish football leagues. The degree of home advantage was found to vary significantly across the divisions. Furthermore, these divisional differences in home advantage were found to be significantly associated with the mean attendance of each division. In an attempt to understand these findings, every occurrence of two influential events (either a sending-off or penalty scored) reported in a national Sunday newspaper was recorded. The overall frequency of both sendings-off and penalties scored favoured the home side, but again this was not constant across the divisions. In divisions with large crowds, the percentage of home sendings-off was relatively small (30%), compared with no difference (50%) in divisions with smaller crowds. Similarly, the percentage of penalties scored by home sides in divisions with the largest crowds was large ( > 70%), in contrast to little or no advantage in divisions with smaller crowds. Two possible explanations for these findings were proposed. Either larger crowds were able to provoke the away player into more reckless behaviour (real fouls), or influence the referee into believing that the away player had committed more fouls (perceived fouls).

Unemployment rate as an updatable health needs indicator for small areas

BACKGROUND

The objective of the study was to compare updatable unemployment rates with the unemployment rate and composite deprivation indices from the 1991 Census as health needs indicators for small areas.

METHODS

Townsend, Carstairs and Jarman indices and male unemployment rates were calculated from the 1991 Census, for 275 wards of the former East Anglian health region with unchanged boundaries between 1981 and 1991. Male unemployment rates were also derived from April 1991 unemployment benefit claimant figures, using both Office of Population Censuses and Surveys mid-year estimates of population and estimates derived from Family Health Services Authority patient registers as the denominator. Ward values were compared using Pearson product moment correlation.

RESULTS

All three unemployment measures were closely related to each other and all were broadly as effective in predicting ward variations in mortality and long-term illness in 1991 as the compound deprivation indices of Jarman. Townsend and Carstairs.

CONCLUSION

Updatable unemployment rates were as suitable as the composite indices as an indicator of relative health needs for small areas in the year of the Census and might be expected to be superior in inter-censal years.

Prepubertal testosterone treatment of female rats: defeminization of behavioral and endocrine function in adulthood

This study assessed the capacity of testosterone (T) administered well after the neonatal "critical" period to permanently sexually differentiate reproductive function. Females received T filled or empty Silastic capsules during days 15-30 of age and vaginal cyclicity, ovarian weight and appearance, lordosis and proceptive behaviors, mounting behavior, and the gonadotropin response to estrogen and progesterone were measured in adulthood. T-treated females (plasma levels of 0.66 ng T/ml) showed constant vaginal estrus from the day of vaginal opening and small, polyfollicular ovaries. Proceptive behaviors were dramatically reduced whether or not the ovaries were present after day 15 of age, but lordosis behavior was not affected. Exposure to T for 5-6 h was ineffective. Compared to controls, T-treated females had dramatically reduced plasma FSH and LH surges. No effects were observed on mounting behavior, phallus size, or body weights. These results suggest that androgen at approximately male levels can act on neural substrates well beyond the neonatal period to permanently defeminize endocrine and behavioral function in the female rat.

Day of injury CT scan as an index to pre-injury brain morphology

This study compared the ventricle-to-brain ratio (VBR) of the day-of-injury (DOI) computerized tomogram (CT) in traumatic brain-injured (TBI) patients with post-injury (2 months or greater) magnetic resonance (MR) VBRs in the same patients and in medical control subjects. The DOI VBR did not differ significantly from the medical controls, but both (DOI and medical control VBR) differed significantly from post-injury VBR. Additionally, a case study is presented wherein MR imaging studies were obtained prior to TBI so that a direct comparison of pre-injury to DOI to post-injury changes could be made. In this case the pre-injury and DOI VBRs were within approximately 9% of each other. In contrast, the post-injury VBR demonstrated over a 100% increase in comparison to either the pre-injury or DOI scan. This case and another case are illustrated using three-dimensional image analysis to represent ventricular change over time. These cases, along with the similarity of the DOI VBR with the medical controls, suggests that the DOI VBR can be utilized as an estimate or index of pre-injury ventricle/brain morphology. This will permit the use of DOI CT data for within-subject designs in TBI research that examines the course of degenerative changes over time.

Peri-operative drug prescribing pattern and manufacturers' guidelines. An audit

Many patients admitted for surgery are receiving regular drug therapy. Adverse effects may occur, either as a result of these drugs being stopped suddenly or because staff are unaware of significant interactions between certain drugs and anaesthetic agents or techniques. This study aimed to find out how regular drug medication is actually given in the peri-operative period. In addition, pharmaceutical companies were contacted and asked for information about the effects of sudden withdrawal of their products and potential interactions with anaesthetic agents. We found that many drugs were omitted peri-operatively with potentially significant effects. Pharmaceutical companies do not seem to appreciate the importance of this problem and not all of them give clear recommendations relevant to practising anaesthetists.

Perinatal outcome of forty-nine pregnancies complicated by acardiac twinning

Acardiac twinning affects 1 in 100 monozygotic twin pregnancies and 1 in 35,000 pregnancies overall. The presence of an acadiac twin requires the normal (or "pump") twin to provide circulation for itself, as well as the acardiac sibling. In many cases the acardiac twin is almost equal to the normal twin. The principal perinatal problems associated with acardiac twinning are pump-twin congestive heart failure, maternal hydramnios, and preterm delivery. We reviewed the perinatal courses of 49 acardiac twin pregnancies to identify factors prognostic of favorable outcome. The overall perinatal mortality was 55%, primarily associated with prematurity. Mean (+/- SD) gestational age at delivery was 29 +/- 7.3 weeks, with a mean (+/- SD) normal twin weight of 1378 +/- 1047 gm. The acardiac weight averaged 651 +/- 571 gm. However, the occurrence of hydramnios, the occurrence of preterm labor, and perinatal outcome were strongly related to the ratio of the acardiac and pump-twin's weight. The mean overall ratio of the twin weights was 52% +/- 42%. However, the mean weight ratio for patients delivered before 34 weeks was 60% versus 29% (p less than 0.04). Preterm delivery was strongly associated with the development of hydramnios and congestive heart failure in the pump twin (p less than 0.01). If the twin-weight ratio was above 70% (25% of cases), the incidence of preterm delivery was 90%; hydramnios, 40%; and pump-twin congestive heart failure, 30% compared with 75%, 30%, and 10%, respectively, when the ratio was less (p less than 0.05). Regression of the weight of the acardiac twin against its longest dimension (L) resulted in this equation for prediction of acardiac weight: Weight (grams) = 1.2 L2-1.7L; r = 0.79, p less than 0.01. These data suggest that estimation of the relative weights in acardiac twins provides prognostic information regarding outcome. Poor outcome occurs with congestive heart failure and hydramnios in the normal twin. Use of the above data may assist in counseling patients and determining optimal management.

Acute anterior compartment syndrome in the thigh: a case report and review of the literature

An unusual case of acute anterior thigh compartment syndrome promptly recognized and successfully treated in a young athletic patient is presented and the literature reviewed. With the increased interest in physical fitness in today's society, this condition may occur more frequently than it is recognized. Prompt diagnosis and treatment can reduce morbidity.

The National Evaluation of School Nutrition Programs: program impact on anthropometric measures

This report describes the anthropometric analysis component of the National Evaluation of School Nutrition Programs. It addresses two research questions: First, is there a relationship between participation in the school nutrition programs and students' height, weight, and triceps fatfold, and, second, are the impacts of program participation on height, weight, and triceps fatfold different for students with different characteristics? The anthropometric analyses suggest that long-term participation in the School Lunch Program has no relationship to height but does have a small relationship to the weight of school-aged children. This is at least partly due to an increase in body fat. Program impacts do not differ for students with different income and ethnic characteristics; however, impacts are greater for older children than for younger children. The School Breakfast Program has no relationship with students' height and only weak relationships with students' weight and triceps fatfold. The Breakfast Program tends slightly to move participants toward the middle of the weight distribution and away from the extremes. Although there are statistically significant increases in weight and triceps fatfold thickness associated with participation in the School Lunch Program, they are small compared with effects of the child's sex, height, and ethnic background. Other variables, such as parents' height and weight, parents' education and family income, also have greater impacts on weight and triceps fatfold measurements than participation in the School Nutrition Programs.

The National Evaluation of School Nutrition Programs: program impact on dietary intake

This article describes the dietary analysis component of the National Evaluation of School Nutrition Programs. It addresses two research questions: 1) do participants and nonparticipants in the school nutrition programs have different calorie and nutrient intakes for 24 h, breakfast, and/or lunch and 2) if there are differences in the nutritional quality or total quantity of food consumed? Students who participate in the School Lunch Program get more than nonparticipants of almost all nutrients that were examined, both at lunch and during 24 h. The superior lunch and 24-h intakes of Lunch Program participants are due to the higher nutritional quality of the School Lunch compared with lunches that nonparticipants eat. The most important impact of the School Breakfast is that when the program is available, it increases the likelihood that children will eat breakfast, and children who eat breakfast have significantly higher intakes of nutrients than children who skip breakfast. The School Breakfast provides more calcium, phosphorus, protein, and magnesium than a non-US Department of Agriculture breakfast, but less vitamin A, vitamin B6, niacin, thiamin, and iron. The positive impacts of calcium and phosphorus carry over 24 h, while the negative impacts for vitamin A, vitamin B6, niacin, thiamin, and iron are made up during the remainder of the day. Although strong conclusions cannot be drawn about the impact of the Milk Program, milk is an important component of all US Department of Agriculture school nutrition programs and makes a major contribution to student dietary intake. Its presence in the meal patterns probably accounts for some of the greater nutrient intakes associated with participation in the School Lunch Program and most of the greater intakes associated with participation in the School Breakfast Program.

Synthesis of sulphated proteoglycans by rheumatoid and normal synovial tissue in culture

Synthesis of sulphated proteoglycans by cell lines derived from explants of 7 rheumatoid and 9 normal specimens of synovial tissue, as well as by 7 lines of skin fibroblasts from non-rheumatoid patients, was examined. Cells of all 3 types were cultured as monolayers. They were then disaggregated and their capacity to synthesise proteoglycan estimated in cell suspensions by the incorporation of [35S]-sulphate into CPC-precipitable material during 2 hours of incubation. Cell suspensions incorporated somewhat more [35S]-sulphate than corresponding duplicate monolayers. Synovial cells from rheumatoid patients incorporated 2 to 3 times as much [35S]-sulphate as synovial cells from normals. Skin fibroblasts, however, incorporated less [35S]-sulphate than rheumatoid or normal synovial cells up to the fifth passage. Thereafter their incorporation gradually increased to overtake that of synovial cells. About one-half to one-third of the total [35S]-sulphate labelled material was closely associated with cells from synovial tissues and fibroblasts respectively.