Design: Case reports.

Results: Two patients had development of visual loss 3 days to 2 weeks after the booster administration of 20 mu g of recombinant hepatitis B virus surface antigen (Engerix-B). In both cases, fundus examination, fluorescein angiograms, and the course of the disease were typical of acute posterior multifocal placoid pigment epitheliopathy. In case 1, 1 week after immunization, the leukocyte count was 10.3 X 10(9)/L with 24% polynuclear eosinophils (2.47 X 10(9)/L); in case 2, blood cell counts were normal.

Conclusion: Hepatitis B virus immunization may be a risk factor for acute posterior multifocal placoid pigment epitheliopathy. Molecular mimicry between a retinal pigment epithelium protein and hepatitis B surface antigen could play a role. These cases suggest an immune-mediated retinal pigment epithelium disruption or choroidal vascular occlusions triggered by hepatitis B surface antigen.

Methods-A retrospective study of the populations of the Brittany and Loire regions in west France was made from 1 January 1982 to 31 December 1991. All internal medicine and rheumatology practitioners of these regions were consulted.

Results-Sixty-two (62) cases were reported (93% response). The disease incidence calculated over five years was 0 . 16 per 100 000 inhabitants in the study population. There was no sex bias (sex ratio 1 . 06 in ASD v 1 . 05 in the overall population. The mean age of the study population was 36 years, with two peaks of distribution at 15-25 and 36-45 years. A history of allergy was present in 23% of patients (n = 14). In two patients, it was possible to correlate an environmental allergen to exacerbation of ASD.

Conclusion-The yearly incidence of ASD was estimated to be 0 . 16 per 100 000 inhabitants. However, it was not possible to incriminate any infectious, toxic, or genetic factors in exacerbation of the disease.

The incidence of infra-clinical deficiencies was estimated to be 55% by examining dietary vitamin A intake, 21% by using the RDR test, 6% by the ICT and 2% from serum retinol values. a These variations are not due to the choice of threshold values for each of the methods, yet rather to poor correlations between the results given by these methods. Canonical correlation analyses indicate that some parameters related to retinol secretion from the liver including Zn, prealbumin and retinol-binding protein, can affect individual patient response towards the different methods. Validation of the RDR test in this elderly population was not successful because of poor reproducibility and moderate correction of RDR-detected vitamin A deficiencies by vitamin A supplementation.

The method chosen for the determination of vitamin A status in elderly people must be carefully evaluated to account for possible age-related changes in the patient response to the method employed In the institutionalized elderly population examined in this study, we observed a low vitamin A intake, whereas serum retinol and ICT are within normal ranges and while RDR test's responses appear too variable to draw any conclusion.

The generality of the property in plants led to search for its origin: apical meristem own dynamics, ontogenetic evolution of internal relationships, dialectical relationships between the plant and its environment.

Some models were put forward to account for the development of Antithamnion but did not take into account the heteroblasty phenomenon. The investigations presented here are a first attempt at representation through formal grammar, based on double wall map systems. The model leads to the assumption of the occurrence of an oscillatory mechanism associated with a threshold that determines both qualitatively (axial cell of the cladomophoric or pleuridiophic type) and quantitatively the development of the whorls.

Methods. - Five observers, having never used EES, followed to EES examinations for a 3-6 month period. They then reviewed the standardized records of 29 patients with cardio-oesophageal cancer. They had to evaluate the degree of tumour infiltration within oesophageal wall and the site of metastatic lymph nodes. Results were compared with the diagnosis of 5 experienced senior endoscopists. Interobserver agreement was estimated with kappa statistics and considered excellent for k greater than or equal to 0.75, good to moderate if 0.75 > k greater than or equal to 0.40, and poor if k < 0.40.

Results. - Inter-observer agreement was poor for the topographic diagnosis of lymph nodes (kappa index from - 0.09 to 0.33), lower to that of the 5 senior observers (0.33 to 0.77). It was satisfactory for degree of tumour infiltration (T1 : k = 0.66, T2 : k = 0.58; T3: k = 0.56; T4 : k = 0.46). The individual sensitivities were weak according to lymph nodes site, but good for presence of lymph nodes (86 to 100 %), with a specificity of 40 to 73 %.

Conclusions. - After theoretical training of EES, agreement and diagnostic performances are good enough to diagnose pathological images (except for T4 tumors), and poor for localizing images in the mediastinum. This emphasizes the difficulties in learning echo-anatomy and gives useful guidelines for training programs in EES.