Patients' perspective on how to improve the care of people with chronic conditions in France: a citizen science study within the ComPaRe e-cohort

Background

This study aimed to involve patients with chronic conditions in generating ideas for improving their care.

Methods

We performed a citizen science study. Participants were adult patients with chronic conditions recruited in Community of Patients for Research ‘ComPaRe,’ a French e-cohort of patients with chronic conditions. Participants generated ideas to improve their care in answer to the open-ended question, ‘If you had a magic wand, what would you change in your healthcare?’ Three researchers and two patients independently extracted ideas from open-ended answers by using thematic analysis. Ideas were grouped into areas for improvement at the consultation, hospital/clinic and health system levels. Findings were validated and enriched by a second sample of participants recruited in ComPaRe.

Results

Between May 2017 and April 2018, a total of 1636 patients provided 3613 ideas to improve consultations (1701 ideas related to 58 areas for improvement), hospitals/clinics (928 ideas related to 41 areas for improvement) and the health system (984 ideas related to 48 areas for improvement). At the consultation level, most ideas were related to improving physician–patient discussions, informing patients about their own care, and adapting treatment to patient preferences and context. At the hospital/clinic level, most ideas aimed at improving the coordination and collaboration in care. At the health system level, most ideas were related to decreasing the administrative burden imposed on patients, improving access to care and reducing the costs of care.

Conclusion

Patients have many ideas to improve their care, from the content of consultations to the organisation of hospitals. Our study provides the proof of concept for a method to leverage patients’ practical knowledge of the care system to improve it.

Acceptable medication non-adherence: A crowdsourcing study among French physicians for commonly prescribed medications

Background

Achieving good medication adherence is a major challenge for patients with chronic conditions. Our study aimed to assess the Threshold for Unacceptable Risk of Non-adherence (TURN), defined as the threshold at which physicians consider the health risks incurred by patients due to medication non-adherence unacceptable, for the most commonly prescribed drugs in France.

Methods

We conducted an online study using a crowdsourcing approach among French general practitioners and specialists from September 2016 to August 2017. Physicians assessed the TURN for various levels of missed doses by evaluating a series of randomly presented clinical vignettes, each presenting a given medication with a given therapeutic indication. For each “drug-indication group” (i.e., all drugs from the same pharmacological class with a similar therapeutic indication): 1) we described the distribution of physicians’ assessments, 2) we provided a summary estimate of the TURN, defined as the frequency of missed doses above which 75% of the physicians’ assessments were located; 3) we computed the number of pill boxes reimbursed in France in 2016 to put our results into context.

Results

We collected a total of 5365 assessments from 544 physicians, each of whom evaluated a random sample among 528 distinct clinical vignettes. Estimates of the TURN varied widely across drug-indication groups, ranging from risk considered unacceptable with 1 daily dose missed per month (e.g., insulin for diabetes) to risk always considered acceptable (e.g., anti-dementia drugs). Drugs with an estimated TURN of over one missing daily dose per week represented 44.9% of the prescription volume of the medications assessed in our study.

Conclusions

According to physicians, the impact of non-adherence may vary greatly. Patient-physician discussions on the variable consequences of non-adherence could lead to a paradigm shift by seeking to reach “optimal adherence” depending on drugs rather than unrealistic “perfect adherence” to all drugs.

Avoidable workload of care for patients living with HIV infection in Abidjan, Côte d'Ivoire: A cross-sectional study

OBJECTIVE

People living with HIV infection (PLWHIV) in Sub-Saharan Africa cope with an increasing workload of care (doctor visits, lab tests, medication management, refills, etc.) in a context of poor health service organization. We aimed to describe the workload of care for PLWHIV in Sub-Saharan Africa and assess to what extent simple adjustments in care organization could reduce this workload of care.

METHODS

Adult PLWHIV under antiretroviral treatment for at least 1 year were recruited in three centers (two public, one private) in Abidjan, Côte d'Ivoire. Using methods inspired from sociology, we precisely described all health-related activities (HRAs) performed by patients, in 1 month, in terms of time, money and opportunity costs. Then, we assessed the theoretical avoidable workload of care if patients' visits and tests had been grouped on the same days.

RESULTS

We enrolled 476 PLWHIV in the study. Patients devoted 6.7 hours (SD = 6.3), on average, in HRAs per month and spent 5% (SD = 11) of their monthly revenue, on average, on health activities. However, we found great inter-patient heterogeneity in the mixture of activities performed (managing medications; dietary recommendations; visits, tests, support groups; administrative tasks; etc.) and their time allocation, temporal dispersion and opportunity costs (personal, familial, social or professional costs). For 22% of patients, grouping activities on the same days could reduce both time and cost requirements by 20%.

CONCLUSION

PLWHIV in Côte d'Ivoire have a heavy workload of care. Grouping visits and tests on the same days may be a simple and feasible way to reduce patients' investment of time and money in their care.

Avoidable waste of research related to outcome planning and reporting in clinical trials

BACKGROUND

Inadequate planning, selective reporting, and incomplete reporting of outcomes in randomized controlled trials (RCTs) contribute to the problem of waste of research. We aimed to describe such a waste and to examine to what extent this waste could be avoided.

METHODS

This research-on-research study was based on RCTs included in Cochrane reviews with a summary of findings (SoF) table. We considered the outcomes reported in the SoF tables as surrogates for important outcomes for patients and other decision makers. We used a three-step approach. (1) First, in each review, we identified, for each important outcome, RCTs that were excluded from the corresponding meta-analysis. (2) Then, for these RCTs, we systematically searched for registrations and protocols to distinguish between inadequate planning (an important outcome was not reported in registries or protocols), selective reporting (an important outcome was reported in registries or protocols but not in publications), and incomplete reporting (an important outcome was incompletely reported in publications). (3) Finally, we assessed, with the consensus of five experts, the feasibility and cost of measuring the important outcomes that were not planned. We considered inadequately planned or selectively or incompletely reported important outcomes as avoidable waste if the outcome could have been easily measured at no additional cost based on expert evaluation.

RESULTS

Of the 2711 RCTs included in the main comparison of 290 reviews, 2115 (78%) were excluded from at least one meta-analysis of important outcomes. Every trial contributed to 55%, on average, of the meta-analyses of important outcomes. Of the 310 RCTs published in 2010 or later, 156 were registered. Inadequate planning affected 79% of these RCTs, whereas incomplete and selective reporting affected 41% and 15%, respectively. For 63% of RCTs, we found at least one missing important outcome for which the waste was avoidable and for 30%, the waste was avoidable for all important outcomes.

CONCLUSIONS

Most of the RCTs included in our sample did not contribute to all the important outcomes in meta-analyses, mostly because of inadequate planning or incomplete reporting. A large part of this waste of research seemed to be avoidable.

Patients' perspectives on how to decrease the burden of treatment: a qualitative study of HIV care in sub-Saharan Africa

Objective

Patients living with HIV infection (PLWH) in sub-Saharan Africa face an important burden of treatment related to everything they do to take care of their health: doctor visits, tests, regular refills, travels, and so on. In this study, we involved PLWH in proposing ideas on how to decrease their burden of treatment and assessed to what extent these propositions could be implemented in care.

Methods

Adult PLWH recruited in three HIV care centres in Côte d’Ivoire participated in qualitative interviews starting with ‘What do you believe are the most important things to change in your care to improve your burden of treatment?’ Two independent investigators conducted a thematic analysis to identify and classify patients' propositions to decrease their burden of treatment. A group of experts involving patients, health professionals, hospital leaders and policymakers evaluated each patient proposition to assess its feasibility.

Results

Between February and April 2017, 326 participants shared 748 ideas to decrease their burden of treatment. These ideas were grouped into 59 unique patient propositions to improve their personal care and the organisation of their hospital or clinic and/or the health system. Experts considered that 27 (46%), 19 (32%) and 13 (22%) of patients' propositions were easy, moderate and difficult, respectively, to implement. A total of 118 (36%) participants offered at least one proposition considered easily implementable by our experts.

Conclusion

Asking PLWH in sub-Saharan Africa about how their care could be improved led to identifying meaningful propositions. According to experts, half of the ideas identified could be implemented easily at low cost for minimally disruptive HIV care.

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.

Discordance Between Drug Adherence as Reported by Patients and Drug Importance as Assessed by Physicians

PURPOSE

Among patients on long-term medical therapy, we compared (1) patient and physician assessments of drug adherence and of drug importance and (2) drug adherence reported by patients with drug importance as assessed by their physicians.

METHODS

We recruited to the study patients receiving at least 1 long-term drug treatment from both hospital and ambulatory settings in France. We compared drug adherence reported by patients and drug importance assessed by physicians using Spearman correlation coefficients. Reasons for nonadherence were collected with open-ended questions and classified as intentional or unintentional.

RESULTS

Between April and August 2014, we recruited 128 patients taking 498 drugs. Patients and physicians showed only weak agreement in their assessments of drug adherence (r = -0.25; 95% CI, -0.37 to -0.11) and drug importance (r = 0.07; 95% CI, 0.00 to 0.13). We did not find any correlation between physician-assessed drug importance and patient-reported drug adherence (r = -0.04; 95% CI, -0.14 to 0.06). In all, 94 (18.9%) of the drugs that physicians considered important were not correctly taken by patients. Patients intentionally did not adhere to 26 (48.1%) of the drugs for which they reported reasons for nonadherence.

CONCLUSIONS

We found substantial discordance between patient and physician evaluations of drug adherence and drug importance. Nearly 20% of drugs considered important by physicians were not correctly taken by patients. These findings highlight the need for better patient-physician collaboration in drug treatment.

Impact of a store-and-forward teledermatology intervention versus usual care on delay before beginning treatment: A pragmatic cluster-randomized trial in ambulatory care

Introduction

In France, 66% of patients forego getting specialized care by dermatologists because of difficulty obtaining appointments. Store-and-forward teledermatology could improve how promptly treatment begins by reducing the delay in obtaining a specialist’s opinion. In this study, we compared the delay before care between general practitioners (GPs) using a store-and-forward teledermatology intervention and GPs addressing their patients with a standard referral letter.

Methods

We performed an open-label, pragmatic cluster-randomized controlled trial with two parallel arms. GP clinics in Paris (France) were randomly assigned to use either teledermatology referral (use of electronics to send clinical images taken using a mobile phone) or conventional referral (using standard letters) to care for patients for whom a dermatologist’s advice was needed for the diagnosis or treatment of skin lesions. Dermatologists integrated responses to teledermatology requests in their usual schedule. Patients were followed up for three months. Primary outcome was the delay, in days, between the GP’s consultation and a reply by the specialist allowing treatment to begin. Analyses were adjusted for clustering of GPs and identities of dermatologists.

Results

Between February and June 2014, 103 patients were included in the study (53 patients of 20 GPs in the intervention group). The median delay between the initial GP’s consultation and the reply allowing for treatment to begin was four days in the intervention group and 40 days in the control group (adjusted hazard ratio = 2.55; p < 0.011).

Discussion

We showed that a simple store-and-forward teledermatology intervention significantly reduced the delay before beginning care (ClinicalTrials.gov identifier: NCT02122432).

Frugal innovation in medicine for low resource settings

Whilst it is clear that technology is crucial to advance healthcare: innovation in medicine is not just about high-tech tools, new procedures or genome discoveries. In constrained environments, healthcare providers often create unexpected solutions to provide adequate healthcare to patients. These inexpensive but effective frugal innovations may be imperfect, but they have the power to ensure that health is within reach of everyone. Frugal innovations are not limited to low-resource settings: ingenuous ideas can be adapted to offer simpler and disruptive alternatives to usual care all around the world, representing the concept of "reverse innovation". In this article, we discuss the different types of frugal innovations, illustrated with examples from the literature, and argue for the need to give voice to this neglected type of innovation in medicine.

Development and validation of an instrument to assess treatment adherence for each individual drug taken by a patient

OBJECTIVE

To develop and validate an instrument to assess adherence to each individual drug taken by patients undergoing long-term treatment.

DESIGN

Multicentre prospective observational validation study.

SETTING

Six general practitioners' clinics and 6 university hospitals in Paris, France.

PARTICIPANTS

Patients 18 years and older receiving at least one long-term treatment.

METHODS

The instrument was developed from a literature search and interviews with experts. Clarity and wording were assessed during pilot testing with 51 patients. The tool was validated in a sample of consecutive patients. We assessed agreement between adherence measured with our tool and drug diaries and compared measurements from our instrument with (1) the Lu instrument; (2) the Adherence Estimator (AE); (3) patient's adherence assessed by physicians; (4) the Morisky Medication Adherence Scale-4 items (MMAS-4); and (5) the Treatment Burden Questionnaire (TBQ). Reliability was assessed by a test-retest method.

RESULTS

A total of 243 patients taking 961 drugs were recruited in 2014. We found good agreement between adherence measured by our tool and drug diaries (intraclass correlation coefficient (ICC) 0.69, 95% CI 0.34 to 0.91) and a linear relationship between measurement with our tool and (1) the Lu instrument (p<0.01); (2) 2 items of the AE (perceived need for medication (p<0.01) and concerns about medication (p<0.01)); (3) patients' adherence assessed by their physicians (p<0.01); (4) the MMAS-4 (p<0.01) and (5) the TBQ (p<0.01). Reliability of the retest was good (ICC 0.67, 95% CI 0.42 to 0.85).

CONCLUSIONS

We developed an instrument with acceptable validity and reliability to assess adherence for each drug taken by patients, usable in hospital and primary care settings.

Taxonomy of the burden of treatment: a multi-country web-based qualitative study of patients with chronic conditions

BACKGROUND

Management strategies for patients with chronic conditions are becoming increasingly complex, which may result in a burden of treatment for patients. To develop a Minimally Disruptive Medicine designed to reduce the burden of treatment, clinicians need to understand which healthcare tasks and aggravating factors may be responsible for this burden. The objective of the present study was to describe and classify the components of the burden of treatment for patients with chronic conditions from the patient's perspective.

METHODS

We performed a multi-country qualitative study using an online survey and a purposive sampling strategy to select English-, French-, and Spanish-speaking participants with different chronic conditions. Participants were recruited by physicians, patients' associations, advertisement on social media, and 'snowballing'. The answers were analyzed by i) manual content analysis with a grounded theory approach, coded by two researchers, and ii) automatic textual analysis by Reinert's method.

RESULTS

Between 2013 and 2014, 1,053 participants from 34 different countries completed the online survey using 408,625 words. Results from both analyses were synthesized in a taxonomy of the burden of treatment, which described i) the tasks imposed on patients by their diseases and by their healthcare system (e.g., medication management, lifestyle changes, follow-up, etc.); ii) the structural (e.g., access to healthcare resources, coordination between care providers), personal, situational, and financial factors that aggravated the burden of treatment; and iii) patient-reported consequences of the burden (e.g., poor adherence to treatments, financial burden, impact on professional, family, and social life, etc.). Our findings may not be applicable to patients with chronic conditions who differ from those who responded to our survey.

CONCLUSIONS

Our taxonomy of the burden of treatment, provided by patients with chronic conditions from different countries and settings, supports the development of tools to ascertain the burden of treatment and highlights potential targets for interventions to minimize it.

Adaptation and validation of the Treatment Burden Questionnaire (TBQ) in English using an internet platform

BACKGROUND

Treatment burden refers to the workload imposed by healthcare on patients, and the effect this has on quality of life. The Treatment Burden Questionnaire (TBQ) aims to assess treatment burden in different condition and treatment contexts. Here, we aimed to evaluate the validity and reliability of an English version of the TBQ, a scale that was originally developed in French.

METHODS

The TBQ was translated into English by a forward-backward translation method. Wording and possible missing items were assessed during a pretest involving 200 patients with chronic conditions. Measurement properties of the instrument were assessed online with a patient network, using the PatientsLikeMe website. Dimensional structure of the questionnaire was assessed by factor analysis. Construct validity was assessed by associating TBQ global score wıth clinical variables, adherence to medication assessed by Morisky's Medication Adherence Scale (MMAS-8), quality of life (QOL) assessed by the PatientsLikeMe Quality of Life Scale (PLMQOL), and patients' confidence in their knowledge of their conditions and treatments. Reliability was determined by a test-retest method.

RESULTS

In total, 610 patients with chronic conditions, mainly from the USA, UK, Canada, Australia, or New Zealand, completed the TBQ between September and October 2013. The English TBQ showed a unidimensional structure with Cronbach α of 0.90. The TBQ global score was negatively correlated with the PLMQOL score (rs = -0.50; p < 0.0001). Low rather than moderate or high adherence to medication was associated with high TBQ score (mean [SD] TBQ score 61.8 [30.5] vs. 37.7 [27.5]; P < 0.0001). The treatment burden was higher for patients who had insufficient knowledge compared with those who had sufficient knowledge about their treatments (mean ± SD TBQ score 62.3 ± 31.3 vs. 47.8 ± 30.4; P < 0.0001) and conditions (63.0 ± 31.6 vs. 49.3 ± 30.7; P < 0.0001). The intraclass correlation coefficient for the retest (n = 282) was 0.77 (95% CI 0.70 to 0.82).

CONCLUSIONS

We found that the English TBQ is a reliable instrument in this population, and provide evidence supporting the construct validity for its use to assess treatment burden for patients with one or more chronic conditions in English-speaking countries.

Development and description of measurement properties of an instrument to assess treatment burden among patients with multiple chronic conditions

BACKGROUND

Patients experience an increasing treatment burden related to everything they do to take care of their health: visits to the doctor, medical tests, treatment management and lifestyle changes. This treatment burden could affect treatment adherence, quality of life and outcomes. We aimed to develop and validate an instrument for measuring treatment burden for patients with multiple chronic conditions.

METHODS

Items were derived from a literature review and qualitative semistructured interviews with patients. The instrument was then validated in a sample of patients with chronic conditions recruited in hospitals and general practitioner clinics in France. Factor analysis was used to examine the questionnaire structure. Construct validity was studied by the relationships between the instrument's global score, the Treatment Satisfaction Questionnaire for Medication (TSQM) scores and the complexity of treatment as assessed by patients and physicians. Agreement between patients and physicians was appraised. Reliability was determined by a test-retest method.

RESULTS

A sample of 502 patients completed the Treatment Burden Questionnaire (TBQ), which consisted of 7 items (2 of which had 4 subitems) defined after 22 interviews with patients. The questionnaire showed a unidimensional structure. The Cronbach's α was 0.89. The instrument's global score was negatively correlated with TSQM scores (rs = -0.41 to -0.53) and positively correlated with the complexity of treatment (rs = 0.16 to 0.40). Agreement between patients and physicians (n = 396) was weak (intraclass correlation coefficient 0.38 (95% confidence interval 0.29 to 0.47)). Reliability of the retest (n = 211 patients) was 0.76 (0.67 to 0.83).

CONCLUSIONS

This study provides the first valid and reliable instrument assessing the treatment burden for patients across any disease or treatment context. This instrument could help in the development of treatment strategies that are both efficient and acceptable for patients.

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.