AB1570-PARE PROFILING LOW BACK PAIN PATIENTS FOR THE DEVELOPMENT OF A PERSONALIZED COACHING APPLICATION

Background

Low back pain is a major public health problem that is increasing with the aging of the population. It is the leading cause of disability in most countries [1]. The recommendations of Inserm (2019) include personalized physical activity programs according to the individual characteristics (motivation, preferences, attitude towards physical activity) and life context of each patient (family and professional load, socioeconomic level, living place) [2]. However, the current management of chronic low back pain includes rehabilitation programs that are costly and/or not always personalized, which reduces their effectiveness.

Objectives

The objective of this research is to better understand the characteristics of people with chronic low back pain to identify main motivational profiles that will allow us to offer personalized coaching via a mobile application.

Methods

After a review of the literature and following advice from experts in the management of chronic low back pain, we selected 8 scales to characterize patients: General Health Status (MYMOP), Treatment Burden (TBQ), Quality of Life (EQ-5D-5L), Level (IPAQ), Fears and Beliefs (FABQ-AP), and Motivation (EMAPS) for physical activity, Emotional Status (PHQ-9), and Sense of Self-Efficacy (FC-CPSES). These questionnaires were administered online to participants in the ComPaRe (Community of Patients for Research) chronic low back pain cohort. An initial descriptive analysis of the results allowed us to describe our sample. In order to distinguish different motivational profiles of patients towards physical activity, we performed a Agglomerative Hierarchical Clustering (AHC) and a principal component analysis (PCA) of the results of the EMAPS, PHQ-9, FABQ-AP and FC-CPSES scales.

Results

A total of 193 patients with chronic low back pain were included (m ≃ 54years, s ≃ 13years; majority women (74%); duration of low back pain: m ≃ 15years, s ≃ 12years; occupational status: 44% employed, 22% on disability, 19% retired). Clustering analysis allowed us to distinguish 4 main profiles that we named as follows: (1) “Amotivated,” characterized by the lowest motivation and highest amotivation toward physical activity (i.e. they do not understand why it is useful), (2) “Cautious” with low motivation and having the highest fears and beliefs toward physical activity, (3) “Depressed” with good intrinsic motivation but also a significant level of depressive symptoms, and (4) “Confident” also showing good intrinsic motivation and having the highest sense of self-efficacy.

Conclusion

The main novelty of this research is a new classification of 4 motivational profiles in the low back pain population determined by a clustering method. This typology is in line with the HAPA model of behavior change [3]. It will allow us to make recommendations for the design of a personalized mobile coaching application. Future work will aim to test and evaluate the personalization of e-coaching according to these profiles.

References

[1]Hurwitz, E.L., Randhawa, K., Yu, H. et al. Initiative mondiale de soins de la colonne vertébrale: un résumé du fardeau mondial des études sur les douleurs lombaires et cervicales. Eur Spine J 27, 796–801 (2018). https://doi.org/10.1007/s00586-017-5432-9

[2]Julie Boiche, Béatrice Fervers, Damien Freyssenet, Isabelle Gremy, Thibaut Guiraud, et al. Activité physique: Prévention et traitement des maladies chroniques. [Rapport de recherche] Institut national de la santé et de la recherche médicale(INSERM). 2019, Paris: Inserm: Éditions EDP Sciences (ISSN: 0990-7440) / 824 p.〈inserm-02102457〉

[3]Schwarzer, R. (2016). Health action process approach (HAPA) as a theoretical framework to understand behavior change. Actualidades en Psicología, 30(121), 119–130. https://doi.org/10.15517/ap.v30i121.23458

Disclosure of Interests

None declared

Quality of life in neurofibromatosis 1: development and validation of a tool dedicated to cutaneous neurofibromas in adults

BACKGROUND

Cutaneous neurofibromas (cNF), present in 95% of individuals with neurofibromatosis 1 (NF1), are considered as one of the greatest medical burden because of physical disfigurement. No specific score evaluates their impact on quality of life (QoL).

OBJECTIVE

To develop a specific score assessing cNF-related QoL.

METHODS

Through a multidisciplinary workshop including 10 patients, 3 expert-in-NF1 physicians, 3 health care workers (nurses and psychologist) and 1 methodologist, the French version of the Skindex-16 was modified by adding 3 items. The new cNF-Skindex was validated among patients with NF1 recruited in the ComPaRe online cohort, in France (N=284). Construct validity was assessed by comparing it with the EQ-5D-5L, its visual analog scale and the MYMOP2 and by assessing its association with patients' characteristics. Reliability was assessed by a test-retest. An English version of the tool was developed using a back forward translation.

RESULTS

A total of 228 individuals with NF1, with cNF answered the 19-item questionnaire. These items fitted into 3 domains: emotions, symptoms, functioning. One was dropped during analysis because >90% responders were not concerned. The cNF-Skindex significantly correlated with the EQ-5D-5L (N=193) and MYMOP2 (N=210) indicating good external validity: rs 0.38 (p<0.001), and 0.58 (p<0.001) respectively. Having >50 cNF was the only independent variable associated with the total score cNF-Skindex (β=15.88, 95%CI 6.96 - 24.81, p=0.001), and with the 3 sub-scores: "functioning" (β=2.65, 95%CI 0.71 - 4.59, p=0.008), "emotions" (β=17.03, 95%CI 4.11 - 29.96, p=0.010) and "symptoms" (β=3.90, 95%CI 1.95 - 5.85, p<0.001). Test-retest reliability (N=133) found an ICC at 0.96 demonstrating good reproducibility.

CONCLUSION

The cNF-Skindex demonstrated excellent psychometric properties. The global and sub-scores were increased with higher number of cNF arguing for its use in further trials aiming to reduce their number or prevent their development. Cross-cultural validation and evaluation of its responsiveness are the next steps.

P–327 Patients’ perspectives on how to improve the management of endometriosis in France: The ComPaRe-Endometriosis cohort

Study question

How should endometriosis management be improved from the patient’s point of view?

Summary answer

One thousand endometriosis patients proposed 2,587 ideas to improve the management of endometriosis that reflect three main themes: diagnosis, care, and information on the disease.

What is known already

Endometriosis is a gynecologic condition affecting 10% of reproductive-age women. The disease causes severe pelvic pain and has a dramatic impact on women’s quality of life. A mean delay of 7 years was described between onset of symptoms and diagnosis. There is an urgent need to reduce this delay and to rethink endometriosis care in order to adopt a more comprehensive and patient-centered approach, as women are often dissatisfied with the care they receive.

Study design, size, duration

This study was carried out in a random sample of endometriosis patients participating in ComPaRe (Community of Patients for Research), a prospective e-cohort of adult chronic disease patients who will be followed-up for 10 years. Participants complete monthly online questionnaires about their life with their disease(s). Recruitment began in January 2017 and is still ongoing, with currently 44,000 participants, including 10,000 endometriosis patients in the ComPaRe-Endometriosis sub-cohort.

Participants/materials, setting, methods

We selected a random sample of 1,000 participants in ComPaRe-Endometriosis, forming 3 equal groups of age (&lt;25, 25–45, &gt;45 years old) and education (&lt;12, 12–14, &gt;14 years). We conducted a qualitative study to gather their ideas for improving the management of their disease. Participants were asked: “If you had a magic wand, what would you change in your health care?”. One interviewer and two patients independently extracted ideas from the open-ended responses using thematic analysis.

Main results and the role of chance

Patients proposed a total of 2,587 ideas to improve the management of endometriosis, which we classified in three main themes: diagnosis, care, and information on the disease. To improve diagnosis, women proposed 724 ideas classified into 11 areas of improvement, including training of health professionals, taking symptoms seriously, improving the diagnosis process, and recognition of the disease by clinicians. To improve care, patients gave 1,677 ideas classified into 71 areas of improvement. For example, they asked for a better pain management, more listening from caregivers, the reimbursement of care or medical treatments, help in accessing clinicians that are expert in endometriosis, and reduced waiting times for medical appointments and exams. Finally, to improve information on the disease, participants suggested 186 ideas classified into 5 areas of improvement, covering more explanation about the disease, public recognition of endometriosis and general awareness, and more research and more explanation of research results.

Limitations, reasons for caution

The results were reviewed by three people in order to reduce the margin of interpretation in the analysis of this open-ended question, but some subjectivity remains. Generalizability may be difficult because the results are linked to the specificities of the French model of care.

Wider implications of the findings: Through the many ideas proposed by patients, we identified a total of 87 areas for improvement in endometriosis diagnosis, care, and information. These results reflect patients’ expectations in terms of management of their disease and will be useful to design a better global care for endometriosis from the patients’ perspective.

Trial registration number

Not applicable

What makes digital health intrusive? Qualitative findings from an international study on diabetes

Background

Remote digital monitoring (RDM, i.e., using digital devices to monitor patients' health and behavior) is a novel care model that can improve health outcomes for people with chronic conditions. However, it could be intrusive to patients' lives. We sought to understand which aspects of RDM make it intrusive to patients and why.

Methods

We performed content analysis of qualitative data collected by using open-ended questions in an international, online survey with a convenience sample of adults with type 1 or 2 diabetes (February-July 2019). Participants were first shown scenarios describing possible RDM features (i.e. different RDM tools [for glucose or food monitoring], feedback loops [receiving feedback in consultation, or remotely by a physician, or by artificial intelligence], and data handling options [by the public or private sector]).

Results

We analyzed data from 709 participants from 24 countries (38% men, median age 38, 54% type 1). Participants found RDM burdensome (n = 468). Burden arose from RDM features that caused disruption in daily life (e.g., alerts), features that may invite undesirable attention in public (e.g., visible wearable sensors may invite questions about one's health), or from having to adapt one's life to fit in RDM (e.g., adapt one's mealtime routine around food monitoring). Participants wanted control, particularly over sharing food-monitoring data with health care professionals in real-time to receive feedback (n = 440). They felt RDM could expose a delicate topic to 'surveillance' by authority figures (i.e., their data may 'reveal' poor dietary habits, leading to criticism by physicians). Intrusion could take the form of RDM eroding the patient-physician relationship (n = 34), or fear of data misuse (n = 206), which was associated with private-sector financial interests.

Conclusions

Our findings offer directions for minimally intrusive RDM design and show that digital health may cause concerns about stigma and treatment burden.

Key messages

Remote digital monitoring is intrusive when it increases treatment burden and limits patients’ control over their own health. “Minimally intrusive” digital health design could increase patient acceptability and, ultimately, foster scalability.

Plasma electron source for generating a ribbon beam in the forevacuum pressure range

We describe a plasma-cathode electron beam source based on a hollow cathode glow discharge and operating in the forevacuum pressure range that produces a steady-state ribbon beam. The electron beam is generated in the pressure range of 10-30 Pa. A multi-aperture electron extraction and beam formation system is used to provide beam stability and enhanced uniformity of beam current density, allowing the use of this kind of device for beam-plasma surface modification over relatively large areas.

Correlates of body mass index among primary school children in Ho Chi Minh City, Vietnam

OBJECTIVES

To document the prevalence of overweight and obesity and examine associated risk factors.

STUDY DESIGN

A cross-sectional survey was conducted in 16 primary public schools in eight districts of Ho Chi Minh City in 2016. A multistage clustering sampling method was used to collect a sample of 1806 pupils attending the first, second, and third grades (7-9 years).

METHODS

Age- and sex-adjusted body mass index (BMI) status was defined using International Obesity Taskforce cut-offs. Ordered probit regression models were used to assess the association between child BMI and its socio-economic and demographic risk factors. The model was estimated separately for boys and girls to assess the extent to which the socio-economic gradients in BMI vary by gender.

RESULTS

The prevalence of obesity among boys was twice the rate for girls (24.7 vs 12.3%). The prevalence of overweight and obesity were also higher among pupils attending schools located in urban districts than in semi-rural districts. Gender, household wealth, the frequency of having breakfast at home, parental body weight, and school location were strong predictors of child BMI status. The protective effect of having breakfast more frequently at home against the risk of overweight/obesity was more pronounced in girls than in boys. Father's body weight and child BMI were more strongly associated with boys from poorer households than boys from wealthier households, while the differences were not significant for girls.

CONCLUSIONS

The high prevalence of childhood overweight and obesity indicates an urgent need for more gender-specific, effective intervention, and prevention programs.

Tuning Plasmon Resonance in Magnetoplasmonic Nanochains by Controlling Polarization and Interparticle Distance for Simple Preparation of Optical Filters

Magnetoplasmonic Fe₃O₄-coated Ag nanoparticles (NPs) are assembled in large scale (18 × 18 mm²) in order to observe unique modulation of plasmonic coupling and optical tunable application via both external magnetic field and the combination of magnetic dipole and electrostatic interactions of particle-particle and particle-substrate. These large nanochains film exhibits outstanding tunability of plasmonic resonance from visible to near-infrared range by controlling the polarization angle and interparticle distance (IPD). The enormous spectral shift mainly originated from far-field rather than near-field coupling of Ag cores because of the sufficiently large separation between them in which Fe₃O₄ shell acts as spacer. This tunable magnetoplasmonic film can be applicable in the field of anisotropic optical waveguides, tunable optical filter, and nanoscale sensing platform.

Mycotic aneurysm of the descending thoracic aorta. Review and case report

A 74-year-old male presented with bilateral invalidating claudication. A bilateral percutaneous transluminal angioplasty (PTA) with stenting of both superficial femoral arteries was performed but complicated by an urosepsis with Escherichia coli and a septic phlebitis at the site of an intravenous line. The phlebitis was complicated by a local abcedation for which incision and drainage were performed. One month after discharge he was readmitted at our hospital with septic fever and positive hemocultures for Escherichia coli. Positron emission tomography-computed tomographic scan (PET/CT-scan) showed a mycotic aneurysm of the thoracic aorta. Because no cryopreserved donor aorta was available and the aneurysm size rapidly increased, an open in situ repair was performed with a Dacron silver prosthesis soaked in rifampicin. His recovery was further complicated by a perforated toxic megacolon for which a subtotal colectomy was performed. Further recovery was uncomplicated and 10 months after the aortic repair patient is still free from infection.

Differential Inflammatory Involvement in Retina and Choroïd in Birdshot Chorioretinopathy

BACKGROUND

Birdshot chorioretinopathy is characterised by dual unrelated inflammatory involvement of the retina and the choroid. Indocyanine green angiography made it possible to assess and follow choroidal disease with the same precision as retinal involvement was followed so far. The aim of this study was to analyse the severity, progression and response to therapy of both retinal involvement using fluorescein angiography and choroidal involvement using indocyanine green angiography.

PATIENTS AND METHODS

Patients with birdshot retinochoroidopathy followed at La Source Eye Centre in Lausanne, Switzerland from January 1995 to December 2002 were subdivided into three subgroups according to the duration of evolution of the disease: untreated patients with no more than one year duration of the disease (group 1, n = 6); treated patients with disease duration of 1 - 7 years duration (group 2, n = 5) and patients with disease lasting for more than 7 years (group 3, n = 4). Fluorescein and indocyanine green angiographic signs (angiographic scores given by a masked observer) were analysed in the 3 groups and compared to the "cream-coloured" fundus lesions.

RESULTS

Fifteen out of the 742 patients (2.0 %) seen at La Source Eye Centre during the time period considered presented BC and were included in the study. In the "early disease group" fluorescein and ICG angiography showed more severe choroidal than retinal involvement with respective scores of 3 +/- 0.79 (ICG) and 2 +/- 1.17 (FA) while there were few depigmented fundus lesions to be seen (score 1 +/- 0.27). The choroidal involvement responded well to systemic corticosteroids +/- immunosuppressive therapy (scores in groups 2 and 3 = 1.2 and 0.75), while retinal disease was stabilised at best (scores in groups 2 and 3 = 2.2. and 2.4) and depigmented fundus lesions increased (scores in groups 2 and 3 = 2.8 and 3).

CONCLUSION

The evolution and response to therapy of retinal and choroidal disease in birdshot chorioretinopathy have a different course with choroidal disease responding well to therapy while retinal disease is more resistant, possibly explaining the slow deterioration of functional parameters despite therapy. The increase of "cream-coloured" fundus lesions despite good choroidal response to therapy could be explained by depigmentation left behind after resolution of choroidal stromal granulomas, a hypothesis recently confirmed by an autopsy case of birdshot chorioretinopathy.

Value of high-frequency ultrasound biomicroscopy in uveitis

PURPOSE

To determine the use of high-frequency ultrasound biomicroscopy (UBM) in the assessment of inflammatory lesions of the iris, ciliary body, pars plana and peripheral vitreous, and in particular to determine the proportion of cases for which UBM contributed significant additional, hitherto inaccessible, information.

METHODS

Charts of patients seen in the uveitis clinic at University Eye Hospital from November 1994 to September 1999 for whom a UBM investigation had been performed were analysed. UBM was performed in a standard manner, using a Humphrey UBM 840 system. The clinical relevance of the UBM findings was determined for the whole series and for the following six subgroups of patients arbitrarily established according to the type and location of pathology: hypotony, pseudophakic uveitis, iris and ciliary body pathology excluding hypotony, pars plana pathology, scleritis and Toxocara uveitis. Findings were classified as positive when they confirmed a suspected diagnosis of lesional process or when they gave essential information. Findings were classified as essential when they led to the diagnosis or when they modified therapeutic intervention.

RESULTS

During the study period 111 eyes of 77 patients were included. UBM findings contributed essential information that allowed a diagnosis to be reached or that influenced treatment in 43% of cases. It yielded positive findings in 91% of cases, enabling assessment of morphological changes in the iris, ciliary body, and retroiridal and peripheral vitreous induced by intraocular inflammatory or pseudo-inflammatory disorders. Specific UBM signs, present in all patients, were identified in Toxocara uveitis. The groups of patients that benefited most from UBM examination were those with hypotony (83% essential findings) and opaque media (100% essential findings).

CONCLUSION

For uveitis patients with an inflammatory process situated in the iris/ciliary body/pars plana/retroiridal vitreous areas, UBM was of great clinical value and improved the management in a significant manner.

The control of haemolysis during transurethral resection of the prostate when water is used for irrigation: monitoring absorption by the ethanol method

OBJECTIVE

To determine whether the addition of ethanol to water for irrigation during transurethral resection of the prostate (TURP) and monitoring breath ethanol could be used to detect irrigant absorption and to limit free plasma haemoglobin in cases of absorption.

PATIENTS AND METHODS

One hundred patients (46 in Piteå, Sweden and 54 in Uong bi, Vietnam) underwent surgery for benign prostatic hyperplasia (BPH) under an intermittent irrigation technique using water containing 2% ethanol. An expired breath alcohol meter was used to monitor ethanol in the patients' breath every 5 min. Blood samples taken after TURP were assessed for free haemoglobin in 99 patients, and other markers of haemolysis were also evaluated in the Swedish group.

RESULTS

Thirty-two patients had detectable ethanol in their breath. There was a close correlation between the maximum ethanol reading during surgery and the level of free plasma haemoglobin after TURP (r = 0.90, P < 0.001). There was no correlation between the duration of TURP and the free haemoglobin level.

CONCLUSION

Monitoring breath ethanol during TURP assesses absorption and so can help to keep control of haemolysis. It is suggested that the value on the alcohol meter should not be allowed to exceed 0.15 (corresponding to a blood ethanol level of 0.15 per thousand), which should maintain the free plasma haemoglobin level at < 1.0 g/L after TURP. Restricting the operative duration per se is not a reliable safety measure.

[Intraocular hypotony: use of ultrasound biomicroscopy (UBM) for differential diagnosis and its schematic representation]

OBJECTIVES

To determine the use of high-frequency ultrasound biomicroscopy (UBM) in the assessment of hypotony and in particular to determine the proportion of cases for which UBM contributed significant additional hitherto unaccessible information.

PATIENTS AND METHODS

Ultrasound biomicroscopy was performed in a standard manner, using a Humphrey UBM 840 system (Humphrey Instruments, Inc., San Leandro, CA). UBM findings were analysed and the clinical relevance of UBM information was determined for the whole collective.

RESULTS

Twelve patients with hypotony were examined. UBM findings contributed essential information that allowed to reach a diagnosis or that determined the therapeutic attitude in 10 of the 12 hypotonic patients. In two cases the cause of hypotony was tractional ciliary body detachment, in 5 cases it was post-inflammatory atrophy of the ciliary body, in 3 cases it was post-traumatic irido and cyclodialysis, in one case it was supraciliary and suprachoroidal effusion and in the last case it was due to uveal effusion syndrome. Based on these findings we established a schematic approach for hypotony.

CONCLUSIONS

This procedure enabled us to assess the morphological changes found in patients with hypotony. In a majority of cases UBM was useful either to orient therapeutic intervention or to establish a diagnosis. On the base of our findings a schematic approach for hypotony, using UBM, was established.

Ultrasound biomicroscopy in peripheral retinovitreal toxocariasis

PURPOSE

To report ultrasound biomicroscopic features in peripheral retinovitreal Toxocara uveitis.

METHODS

Three patients with unilateral vitreitis suspected to be caused by peripheral toxocariasis were referred for ultrasound biomicroscopic examination of the peripheral retina, pars plana, and adjacent vitreous.

RESULTS

In two of the three patients, characteristic pseudocystic transformation of the peripheral vitreous was seen. In both patients, Toxocara serology was positive and eosinophilia was present. In the third patient, no pseudocystic transformation of the peripheral vitreous was seen; however, there was the dense thickening adjacent to the pars plana usually seen by ultrasound biomicroscopy in pars planitis and corresponding to clinically visible snowbanks. The third patient had a negative Toxocara serology and later developed bilateral intermediate uveitis of the pars planitis type. In none of 48 patients with diverse inflammatory conditions of the retroiridal space that were examined by ultrasound biomicroscopy were the characteristic Toxocara-associated pseudocystic images seen.

CONCLUSIONS

Pseudocystic transformation of the peripheral vitreous appears to be a rather specific and sensitive ultrasound biomicroscopic sign in patients with presumed peripheral toxocariasis that will likely aid diagnosis in difficult cases.

Posterior sub-Tenon's steroid injections for the treatment of posterior ocular inflammation: indications, efficacy and side effects

PURPOSE

Posterior sub-Tenon's steroid injections (PSTSI) are a standard drug delivery method used for the treatment of chronic uveitis of the posterior segment. The aim of this study was to analyse the indications, efficacy and complications of PSTSI in the treatment of chronic uveitis.

METHODS

During the period 1990-1994, 53 (9.5%) of 558 patients (58 eyes) followed up in the uveitis clinic received a total of 162 PSTSI of triamcinolone acetonide 40 mg in the superior quadrants. Indications for treatment were vision inferior or equal to 0.7 and/or intolerable visual disturbance. Only patients in whom PSTSI were the only treatment parameter changed were analysed. Among the main parameters analysed were visual acuity, aqueous laser flare photometry, intraocular pressure (IOP) and complications.

RESULTS

Anatomical location of uveitis was as follows: anterior HLA-B27-related uveitis with CME (1 patient/1 eye), intermediate uveitis (28/32), posterior uveitis (10/10) and panuveitis (14/15). Mean duration of follow-up was 448+/-57 days. Visual acuity improved significantly from 0.40+/-0.03 to 0.79+/-0.07, with 59.4% of eyes having a gain of 2-5 Snellen lines and 18.7% a gain of >5 lines. Mean aqueous flare photometry decreased significantly from 29.6+/-3.5 to 13.6+/-2.2 photons/ms. Mean IOP increased significantly from 13.6+/-0.5 to 18.5+/-0.8 mm Hg with a rise of pressure >8 mm Hg in 23 cases (36%), transient in 16 cases, but chronic in 6 cases, needing filtering surgery. Partial superior ptosis was seen in two cases and cataract progressed in seven cases.

CONCLUSION

PSTSI are very effective in restoring visual acuity in chronic uveitis of the posterior segment, without systemic complications, but at the expense of intraocular hypertension, a complication that was found more frequently than expected.

Effect of cataract surgery with intraocular lens implantation on inflammation in chronic uveitis: a longitudinal laser flare photometry study

BACKGROUND

The precise effect of cataract surgery with implantation of an intraocular lens (IOL) on the course of uveitis is not well known. Laser flare photometry allows quantitative assessment of intraocular inflammation. The aim of this study was to determine the effect of cataract surgery with IOL implantation on the disease course and level of inflammation in chronic uveitis, using laser flare photometry monitoring.

METHODS

The charts of all patients who underwent surgery for secondary uveitic cataract between 1990 and 1994 (24/558 [4.3%]) were reviewed. Only eyes that had received standardized perioperative steroid treatment and had systematic laser flare photometry follow-up were included. Cataracts due to Fuchs' heterochromic cyclitis were excluded. Visual acuity, flare values and recurrence of flare episodes were compared before and after cataract surgery, and postoperative data were compared between eyes that received heparin-coated IOLs and those that received uncoated IOLs.

RESULTS

Nineteen eyes of 16 patients met the inclusion criteria. The mean length of the pre- and- postoperative follow-up periods was 779 and 444 days respectively. The mean visual acuity increased from 0.2 (standard error of the mean [SEM] 0.2) preoperatively to 0.8 (SEM 0.3) postoperatively (p < or = 0.001). The mean flare value decreased from 58.6 (SEM 18.6) photons/ms during preoperative follow-up to 29.7 (SEM 7.8) photons/ms during postoperative follow-up (p < or = 0.006). The mean number of recurrences per 6 months decreased from 0.27 (SEM 0.03) preoperatively to 0.12 (SEM 0.01) postoperatively (p < or = 0.05). The difference in the postoperative recurrence rate between the eyes that received coated IOLs (0.0) and those that received uncoated IOLs (0.18 [SEM 0.02]) approached statistical significance (p < or = 0.054).

INTERPRETATION

Quantitative assessment of inflammation by laser flare photometry in patients undergoing surgery for uveitic cataract showed that there was significantly less inflammation and fewer recurrences postoperatively and that recurrences were less severe.

Need for certainty and interest in genetic testing

The relation among need for certainty, type of information presented about a genetic test, and level of interest in predictive genetic testing was examined. Participants were randomly assigned to receive 1 of 2 descriptions of the test. The only difference between the descriptions was that one included a paragraph that emphasized the cancer risk remaining for those who test negative for gene mutations. As predicted, a significant interaction between need for certainty and type of information presented was observed. Whereas women high in need for certainty were more interested in genetic testing when provided with the standard description and less interested when provided with the more complete one, women low in need for certainty showed the opposite pattern. The results suggest that interest in genetic testing is determined by the correspondence between an individual's personal goals and her perception of the kind of information provided by the test.

Modeling the electrophoresis of rigid polyions: application to lysozyme

An algorithm is developed to determine the electrophoretic mobility of a rigid polyion modeled as a low dielectric volume element of arbitrary shape containing an arbitrary charge distribution. The solvent is modeled as a high dielectric continuum with salt distributed according to the linearized Poisson Boltzmann equation. Account is also taken of a Stern layer that separates the molecular surface and the surface of hydrodynamic shear, or Stern surface. Relaxation of the ion atmosphere because of the presence of the external field is ignored. The electrostatic and hydrodynamic problems are both solved by boundary element methods. The procedure is first applied to spherical polyions containing monopolar, dipolar, and quadrupolar charge distributions, and calculated mobilities are found to be in excellent agreement with the theory of Yoon and Kim. It is then applied to lysozyme by using models that account for the detailed shape and charge distribution of the enzyme. For reasonable choices of the molecular and Stern surfaces, calculated and experimental mobilities are found to be in fair agreement with each other. However, if a pH independent Stern layer (or, equivalently, translational diffusion constant, Dt) is assumed, the calculated mobilities exhibit a stronger pH dependence than is observed experimentally. A small increase in Dt with increasing pH could correct this discrepancy.

Epidemiological characteristics of uveitis in Switzerland

Since January 1990, data from uveitis patients have been systematically stored in a computer data bank. During the period from January 1990 to March 1993, 435 new patients (185 female and 250 male, mean age 43 years; range 6-92) were seen at the Uveitis Clinic of the Hôpital Jules Gonin. These 435 patients (630 eyes) were subdivided into anterior uveitis (268 patients--62%), intermediate uveitis (47 patients--11%), posterior uveitis (89 patients--20%) and panuveitis (31 patients--7%). The incidence of uveitis for the referral area considered was calculated to be 17 per 100,000 inhabitants per year. A specific diagnosis was found in 312 cases (72%). The most frequently diagnosed entities were HLA-B27-associated acute anterior uveitis (67 cases--15.4%), uveitis associated with acute herpes zoster ophthalmicus (40 cases--9.2%), toxoplasmosis (39 cases--9%), typical pars planitis (29 cases--6.7%), sarcoidosis (29 cases--6.7%), Fuchs' heterochromic cyclitis (27 cases--6.2%), herpetic anterior uveitis (21 cases--4.8%) and acute retinal necrosis (11 cases--2.5%). Incidence and distribution of most disease entities correspond to those of other European series.

[Indications and complications of systemic corticosteroid therapy in treatment of uveitis]

PURPOSE

Systemic steroids is often the first choice of immunosuppressive therapy for severe endogenous uveitis. The aim of this study was to analyse the indications of steroid therapy, complications and side-effects.

PATIENTS AND METHODS

Charts from all patients that received oral steroid therapy were reviewed for this purpose and a questionnaire was sent out to all patients to record their subjective complaints.

RESULTS

From January 1990 to March 1993, 63 out of the 435 new patients seen at the uveitis clinic received oral prednisone. In 4 cases severe complications occurred that did however not lead to discontinuation of therapy. In 2 cases of intolerance cyclosporine (CsA) had to be added to the treatment regimen to lower the steroid doses and in one case steroids had to be stopped because of intolerance. The questionnaire showed a high rate of subjective side-effects to steroids.

CONCLUSIONS

In our collective oral steroids were associated with complications, intolerance and side-effects in a high proportion of cases. It is important to explain the possible side-effects to the patient before starting the therapy. The preventable collateral effects like weight gain and decalcification should be addressed by diet recommendations and modern calcium sparing therapy.

[Uveitis in the elderly]

BACKGROUND

There is only scarce information available in the literature on uveitis of older patients. The aim of this study was to study this age group in greater detail.

PATIENTS AND METHODS

435 patients were seen in the uveitis clinic of the University Eye Hospital Jules Gonin from January 1990 to March 1993. We analysed here the 94 (21.8%) patients that presented a first episode of uveitis after the age of sixty.

RESULTS

This collective was characterised by an increased frequency of the anatomic diagnosis of panuveitis (p < 0.0001), and of the specific diagnosis of zoster uveitis (p < 0.0001), sarcoidosis (p < 0.0001), uveitis associated with scleritis (p < 0.05) and granulomatous anterior uveitis (p < 0.01). The frequency of diagnosis of intermediate uveitis was significantly reduced (p < 0.034) as were the specific diagnosis of HLA-B27 positive acute anterior uveitis (p < 0.001), pars planitis (p < 0.08) and non granulomatous anterior uveitis (p < 0.01). Reiter's uveitis, Possner-Schlossmann Syndrome, Behçet's uveitis, Vogt-Koyanagi-Harada disease and Toxoplasmosis retinochoroiditis were never diagnosed in this group of elderly patients. The proportion of defined specific diagnosis (75.5%) was comparable to the group of patients of less than 60 years old.

CONCLUSION

As can be seen from our data, epidemiological characteristics of old age uveitis differ markedly from younger patients which should influence the diagnostic approach in these patients.

Defective lens fiber differentiation and pancreatic tumorigenesis caused by ectopic expression of the cellular retinoic acid-binding protein I

All-trans retinoic acid, a metabolite of retinol, is a possible morphogen in vertebrate development. Two classes of cellular proteins, which specifically bind all-trans retinoic acid, are thought to mediate its action: the nuclear retinoic acid receptors (RAR alpha, beta, gamma), and the cytoplasmic binding proteins known as cellular retinoic acid-binding proteins I and II (CRABP I and II). The function of the retinoic acid receptors is to regulate gene transcription by binding to DNA in conjunction with the nuclear retinoid X receptors (RXR alpha, beta, gamma), which in turn have 9-cis retinoic acid as a ligand. Several lines of evidence suggest that the role of the cellular retinoic acid-binding proteins is to control the concentration of free retinoic acid reaching the nucleus in a given cell. Here, we have addressed the role of the cellular retinoic acid-binding protein I in development by ectopically expressing it in the mouse lens, under the control of the alpha A-crystallin promoter. We show that this ectopic expression interferes with the development of the lens and with the differentiation of the secondary lens fiber cells, causing cataract formation. These results suggest that correct regulation of intracellular retinoic acid concentration is required for normal eye development. In addition, the generated transgenic mice also present expression of the transgene in the pancreas and develop pancreatic carcinomas, suggesting that overexpression of the cellular retinoic acid-binding protein is the cause of the tumors. These results taken together provide evidence for a role of the cellular retinoic acid-binding protein in development and cell differentiation. The relevance of these findings to the possible role of the cellular retinoic acid-binding proteins in the transduction of the retinoic acid signal is discussed.

Intravenous cefazolin in penetrating eye injuries. Treatment of experimental posttraumatic endophthalmitis

The use of intravenous antibiotics as prophylaxis in penetrating eye injuries is strictly empiric and not based on scientific data supporting their use. To determine the efficacy of prophylactic intravenous cefazolin in penetrating eye injuries, a rabbit model of posttraumatic endophthalmitis was developed. Forty rabbits received penetrating eye injuries followed immediately by an intravitreal inoculum of live Staphylococcus epidermidis. The rabbits then were randomly divided into four groups: group 1 received three doses of intravenous cefazolin; group 2 received six doses, and group 3 received nine doses; group 4 received no treatment and served as controls. All control rabbits developed 4+ vitreitis; rabbits receiving three doses of the antibiotic developed 2+ vitreitis, and those receiving six or nine doses of cefazolin showed no vitreous inflammation (P < or = 0.0001). Histologic examination of control eyes showed an exuberant reaction with formation of retrolental membranes, vitreous abscess, and retinal detachment. Eyes treated with nine doses of cefazolin were devoid of inflammatory cells. These findings suggest that intravenous cefazolin is effective in preventing the development of posttraumatic endophthalmitis in a rabbit model.

Human retinal pigment epithelial cells possess beta 2-adrenergic receptors

Beta-adrenergic receptors on cultured human retinal pigment epithelium were demonstrated by the binding of [125I]cyanopindolol. Its pharmacologic specificity was also examined. Specific [125I]cyanopindolol binding was saturable, with a dissociation constant of 130 pM and a receptor density of 12 fmol per one-half million cells, which is equivalent to 14,000 receptor sites per retinal pigment epithelial cell. Agonists competed for specific [125I]cyanopindolol binding, with the following rank order of potencies: (-)-isoproterenol > (-)-epinephrine > (-)-norepinephrine. Beta 2-selective antagonist ICI-118551 was approximately 3 log orders more potent than the beta 1-selective antagonist, betaxolol. These receptors were also coupled to an adenylate cyclase. These results suggest strongly that cultured human retinal pigment epithelial cells possess beta 2-adrenergic receptors. The potential significance of these findings with regard to retinal pigment epithelial functions is discussed herein.

Vitrectomy for perforating eye injuries from shotgun pellets

Pars plana vitrectomy and scleral buckling were performed on 22 eyes of 19 patients for treatment of perforating eye injuries from shotgun pellets. We reviewed the intraoperative findings at the time of vitrectomy to determine what factors might influence final visual acuity. The presence of a total retinal detachment at vitrectomy portended a poor prognosis when compared with eyes without total retinal detachment, as only one of ten eyes with total retinal detachment obtained useful vision (P = .002). Preoperative separation of the posterior vitreous was associated with a favorable outcome when compared with the absence of posterior vitreous detachment (P = .035), as ten of 16 eyes with posterior vitreous detachment at the time of vitrectomy ultimately achieved functional vision. The locations of the exit wounds did not affect visual success in the overall series of patients. However, in the patients who achieved visual success, exit wounds outside the vascular arcades were more likely to be associated with final visual acuities of, or better than, 20/70 than were those within the arcades (P = .022). Other prognostic factors, such as the number of perforations and the use of cryotherapy, were also examined for their effects on final visual outcome. However, these factors did not appear to affect visual outcome statistically.

Postnatal development of the ciliary body and pars plana. A morphometric study in childhood

The ciliary body of the human eye serves many vital functions and provides important access to the posterior segment of the globe in vitreoretinal surgery. Although embryogenesis and prenatal development of the ciliary body have been well documented, continuing development of the ciliary body during early childhood has not been studied extensively. We determined the lengths of the ciliary body and pars plana in 76 normal eyes of subjects who ranged in age from 1 week to 6 years. The ciliary body was found to be of substantial length soon after birth; it measured a mean of 3.06 mm nasally and 3.31 mm temporally. Three quarters of the final length of the ciliary body at adulthood was achieved by age 24 months. The growth of the ciliary body is discussed in relation to the growth of the eye.

Differential localization of dopamine D1 and D2 receptors in rat retina

Dopamine interacts with distinct receptors on different target neurons in the rat retina. Dopamine receptors were labeled in the rat retina by autoradiography using 3H-SCH-23390 and 3H-spiperone binding to retinal sections. The 3H-SCH-23390 binding to D1 receptors was most concentrated in the inner plexiform, inner nuclear, and ganglion cell layers; it was absent from the outer nuclear layer and the photoreceptor inner and outer segments. Competition studies indicated that 3H-SCH-23390 binding to the inner retina was inhibited with high affinities by the D1-specific agonist and antagonist, SKF-38393 and SCH-23390. The D2-specific compounds were ineffective in competing for 3H-SCH-23390 binding. The 3H-spiperone binding to D2 receptors, however, was most concentrated in the photoreceptor inner and outer segments and in the outer nuclear layer. The D2-specific agonist and antagonists, such as quinpirole, sulpiride, and eticlopride, competed for 3H-binding with high affinities; SCH-23390 and SKF-38393 were ineffective. The D2 receptors on the photoreceptors had a high affinity for clozapine but lower affinities for the modified benzamides. This is characteristic of a novel subtype of D2 receptors. Thus, D1 and D2 dopamine receptors are localized differentially in the rat retina to mediate different physiologic effects of dopamine.

Guanine nucleotide-binding regulatory proteins in retinal pigment epithelial cells

The expression of GTP-binding regulatory proteins (G proteins) in retinal pigment epithelial (RPE) cells was analyzed by RNA blot hybridization and cDNA amplification. Both adult and fetal human RPE cells contain mRNA for multiple G protein alpha subunits (G alpha) including Gs alpha, Gi-1 alpha, Gi-2 alpha, Gi-3 alpha, and Gz alpha (or Gx alpha), where Gs and Gi are proteins that stimulate or inhibit adenylyl cyclase, respectively, and Gz is a protein that may mediate pertussis toxin-insensitive events. Other G alpha-related mRNA transcripts were detected in fetal RPE cells by low-stringency hybridization to Gi-2 alpha and Gs alpha protein-coding cDNA probes. The diversity of G proteins in RPE cells was further studied by cDNA amplification with reverse transcriptase and the polymerase chain reaction. This approach revealed that, besides the above mentioned members of the G alpha gene family, at least two other G alpha subunits are expressed in RPE cells. Human retinal cDNA clones that encode one of the additional G alpha subunits were isolated and characterized. The results indicate that this G alpha subunit belongs to a separate subfamily of G proteins that may be insensitive to inhibition by pertussis toxin.

A clinical comparison of the Oculab Tono-Pen with the Goldmann applanation tonometer in eyes filled with silicone oil

Intraocular pressure in 21 eyes filled with silicone oil was measured with two different instruments: the Oculab Tono-Pen and a Goldmann applanation tonometer mounted to a slit lamp biomicroscope. Intraocular pressure ranged from 2 mmHg to 28 mmHg, and the mean difference between readings obtained from the two instruments was 0.64, which was not statistically significant. These results suggest that the Oculab Tono-Pen is an effective instrument with which to measure intraocular pressure in silicone-filled eye.

Somatostatin binding sites in human and monkey brain: localization and characterization

A radioiodinated analogue of somatostatin 28, 125I [Leu8,D-Trp22,Tyr25] SS-28, was used to localize and characterize somatostatin binding sites in both human and monkey brain. High-affinity binding sites (approximately 1 nM) were found in cerebral cortex. The highest binding was in cerebral cortex with intermediate binding found in hippocampus, striatum, and amygdala and low binding in hypothalamus and brainstem. There was a rough correlation between somatostatin receptor binding and concentrations of somatostatin-like immunoreactivity (SLI) in human brain. Somatostatin receptors were stable for up to 24 h in an animal model simulating human autopsy conditions and there was no correlation between postmortem interval and receptor binding in human brain. Pharmacologic characterization in human cortex showed that there was a correlation between the inhibition of receptor binding by somatostatin analogues and their known abilities to inhibit growth hormone secretion. These findings demonstrate that a highly specific membrane-associated receptor for somatostatin is present in both monkey and human brain. Examination of somatostatin receptor binding in Alzheimer's disease and Huntington's disease may improve understanding of the role of somatostatin in both these illnesses.

[Salmonella osteomyelitis in sickle cell anemia]

Case report of a 28-year old black sickle cell anemia patient with salmonella osteomyelitis of the radius. Aside from sickle cell anemia patients this skeletal complication of enteric salmonellosis is an extreme rarity. Description of the typical roentgenological features including intracortical fissures and sequestration.

Reduced numbers of somatostatin receptors in the cerebral cortex in Alzheimer's disease

Somatostatin receptor concentrations were measured in patients with Alzheimer's disease and controls. In the frontal cortex (Brodmann areas 6, 9, and 10) and temporal cortex (Brodmann area 21), the concentrations of somatostatin in receptors in the patients were reduced to approximately 50 percent of control values. A 40 percent reduction was seen in the hippocampus, while no significant changes were found in the cingulate cortex, postcentral gyrus, temporal pole, and superior temporal gyrus. Scatchard analysis showed a reduction in receptor number rather than a change in affinity. Somatostatin-like immunoreactivity was significantly reduced in both the frontal and temporal cortex. Somatostatin-like immunoreactivity was linearly related to somatostatin-receptor binding in the cortices of Alzheimer's patients. These findings may reflect degeneration of postsynaptic neurons or cortical afferents in the patients' cerebral cortices. Alternatively, decreased somatostatin-like immunoreactivity in Alzheimer's disease might indicate increased release of somatostatin and down regulation of postsynaptic receptors.

Two types of somatostatin receptors differentiated by cyclic somatostatin analogs

Somatostatin receptors in rat brain, pituitary, and pancreas were labeled with two radioiodinated analogs of somatostatins 14 and 28. Two cyclic analogs of somatostatin, SMS201-995 and cyclo(Ala-Cys-Phe-D-Trp-Lys-Thr-Cys), showed biphasic displacement of binding to somatostatin receptors by these radioligands. In contrast, all other somatostatin analogs, including somatostatin-14, competed for the receptor sites with monophasic displacement of radioligand receptor binding. Thus two types of somatostatin receptors were identified. It was found that the pituitary and pancreas have predominantly one type of somatostatin receptor whereas the brain has both, and that different regions of the brain have various proportions of the two types. These findings suggest methods to characterize other types of somatostatin receptors subserving somatostatin's diverse physiological functions, including a potential role in cognitive function and extrapyramidal motor system control.

Brain peptidase with a unique neuronal localization: the histochemical distribution of dipeptidyl-aminopeptidase II

To assess whether specific peptidases regulate neuropeptide disposition, we have examined histochemically the localization of dipeptidyl-aminopeptidase II (DAP II). With beta-naphthylamide (beta-NA) substrates, this enzyme has a selectivity for lysyl-alanyl-beta-NA. DAP II staining is highly localized to specific neuronal populations with no staining over glia. Areas in the brain with high densities of DAP II staining include the mitral cells in the olfactory bulb, polymorphic cells in the hippocampus, the paraventricular nucleus of the hypothalamus, and the anterior dorsal thalamus, Purkinje cells, and deep nuclei in the cerebellum. Staining occurs in virtually all cell groups in the inferior colliculus, red nucleus, oculomotor nucleus, and mesencephalic nucleus of the trigeminal nerve, the stratum album of the superior colliculus, as well as most cells in the cochlear and superior olivary nuclei. DAP II localizations do not correlate fully with those on any known neuropeptide. Of the numerous peptides evaluated, only glucagon competes substantially for the DAP Ii substrate, reducing enzymatic activity by 50% at a 2 x 10(-5) M concentration.

[3H]doxepin interactions with histamine H1-receptors and other sites in guinea pig and rat brain homogenates

[3H]Doxepin, a tricyclic antidepressant, binds to brain homogenates with two saturable components. The high affinity component, with a dissociation constant (KD) of 0.26 nM, is associated with histamine H1-receptors. This high affinity binding shows stereospecificity in that d-chlorpheniramine is 100 times more potent than the pharmacologically less active l-isomer. Its drug specificity and regional variation closely parallel those exhibited by [3H]mepyramine binding. The drug specificity of the low affinity component is distinct from that of histamine H1-receptors, with no stereospecificity for chlorpheniramine isomers. Furthermore, all the H1-histamine antagonists tested display micromolar potency at the low-affinity doxepin sites but nanomolar potency at the high-affinity doxepin sites associated with a physiological histamine H1-receptor. The drug specificity of the low affinity site does not correspond to that of any known neurotransmitter receptor. Tricyclic antidepressants display IC50 values of 30-600 nM for the inhibition of [3H]doxepin binding to the low-affinity component with most values in the 0.1-0.3 microM affinity range.

GABA receptors are increased in brains of alcoholics

gamma-Aminobutyric acid (GABA) receptor binding was increased in postmortem brain samples of chronic alcoholic patients compared to control patients. Numbers of binding sites were augmented in alcoholic brain, with no change in affinity. Muscarinic cholinergic and benzodiazepine receptors did not differ between controls and alcoholic brains, while a modest reduction in beta-adrenergic receptors may have been related to postmortem receptor changes. The results suggest that GABAergic mechanisms might play a role in chronic alcoholism.

Histidine decarboxylase. Purification from fetal rat liver, immunologic properties, and histochemical localization in brain and stomach

Histidine decarboxylase from fetal rat liver was purified to near-homogeneity. The purified enzyme has a molecular weight of 210,000, and appears to contain two subunits with molecular weights of 145,000 and 66,000, respectively. The enzyme is inhibited by heavy metals such as Hg2+ and Zn2+ and sulfhydryl-reactive compounds such as 5,5'-dithiobis-2-nitrobenzoic acid. The enzyme is partially dependent on exogenous pyridoxal phosphate. Extensive dialysis results in 50% loss of enzyme activity which can be fully recovered by adding pyridoxal phosphate. Affinity of pyridoxal phosphate for the apoenzyme is 0.1 microM at pH 6.8. Antibody against purified histidine decarboxylase was raised in rabbits. The antibody has been employed in immunohistochemical studies to visualize histidine decarboxylase containing cells and neuronal processes in rat stomach and brain, respectively. Immunologic studies indicate that histidine decarboxylase from brain, gastric mucosa, and fetal rat liver share common antigenic properties.

Histamine H1-receptors labeled in vivo: antidepressant and antihistamine interactions

3H-Mepyramine labels specific histamine H1-receptors in brains of mice after intravenous injection. The potencies of H1-antihistamines in reducing 3H-mepyramine binding in vivo correspond to their pharmacological activities and show parallels with their affinities for 3H-mepyramine binding sites in isolated brain membranes. Several antidepressants are potent in competing for 3H-mepyramine binding in vivo as well as in vitro.

Neurotransmitter receptor localizations: brain lesion induced alterations in benzodiazepine, GABA, beta-adrenergic and histamine H1-receptor binding

Selective neuronal lesions have been utilized in efforts to localize binding sites in rat brain for beta-adrenergic, gamma-aminobutyric acid (GABA), histamine H1 and benzodiazepine receptors. The various receptors respond differentially to lesions both in extent of change and in time course. After kainate lesions in the corpus striatum, benzodiazepine receptors are depleted up to 45% at 45--78 days but are unaffected after 7 days. By contrast striatal GABA receptors are increased at 7 days but depleted at later times. Thus both striatal benzodiazepine and GABA receptors appear to be associated at least in part with intrinsic neurons. In the cerebellum both benzodiazepine and GABA receptors are reduced in kainate treated rats and in Nervous mice, mutants which lack Purkinje cells. The most pronounced dissimilarity between benzodiazepine and GABA receptors occurs in Weaver mice, which selectively lack granule cells and display a 60% reduction in GABA receptors but a 40% augmentation in benzodiazepine receptors. A major portion of cerebellar GABA receptors, therefore, appear to be localized to granule cells. Striatal beta-adrenergic receptors are reduced following intrastriatal kainate injections but are unaffected by cerebral cortex ablation, suggesting an association with intrinsic neurons but not with axon terminals of the corticostriate pathway. While intraventricular injections of 6-hydroxydopamine enhance [3H]dihydroalprenolol binding to beta-adrenergic receptors in the cerebral cortex and hippocampus, such binding is not augmented in the corpus striatum, brain stem, midbrain or thalamus-hypothalamus by this treatment. Moreover, medial forebrain bundle lesions, which destroy ascending adrenergic neurons, fail to alter cerebral cortical or striatal beta-adrenergic receptors. Thus denervation-elicited increases in beta-adrenergic receptors vary with brain region and the type of denervating lesion. Histamine H1-receptors are the most resistant of all to neuronal lesions. In the corpus striatum [3H]mepyramine binding is unaffected by cerebral cortex ablation, nigral injections of 6-hydroxydopamine or brain stem hemisection. In the hippocampus, medial forebrain bundle lesions, intrahippocampal kainate injection, and fimbria and fornix transection largely fail to alter [3H]mepyramine binding. Accordingly, a major portion of these receptors may be associated with nonneuronal elements such as glia or blood vessels.

Characteristics of histamine H1-receptors in peripheral tissues labeled with [3H]mepyramine

Specific binding of [3H]mepyramine to membranes of various peripheral tissues of different species has been demonstrated. Drug specificity indicates an association with histamine H1-receptors. Of all the tissues examined brain contains the highest numbers of binding sites, while substantial levels of specific [3H]mepyramine binding are also demonstrable in some species in heart, lung, adrenal and ileum. Negligible specific [3H]mepyramine binding is observed in the liver, stomach and uterus of several species. The lesser bronchoconstricting response of the rat than of other species to histamine is paralleled by a lower number of [3H]mepyramine binding sites in rat lung than in other species. However, similar numbers or [3H]mepyramine binding sites occur in ileal membranes of rat, guinea pig and rabbit, although contractile effects of histamine vary in these species. In the quinea-pig ileum, [3H]mepyramine binding is most concentrated in the longitudinal muscle itself where histamine exerts its predominant contractile effects. In the bovine adrenal gland, [3H]mepyramine binding is more abundant and has higher affinity for drugs in the medulla than in the cortex.