Organochlorine pollutants in chub, Leuciscus cephalus, from the Svratka River, Czech Republic.

The aim was to evaluate the extent of pollution of the Svratka River with organochlorinated pollutants using the chub (Leuciscus cephalus) as a suitable bioindicator of the river contamination. The sum of 7 PCB congeners was found in range of 7.6-93.8 ng/g (with median of 31.7 ng/g) wet weight (ww), DDTs of 2.9-93.8 (29.9) ng/g ww, HCHs isomers of 0.1-5.3 (1.0) ng/g ww, HCB of 0.3-8.4 (2.2) ng/g ww and OCS of <0.1-0.5 (0.1) ng/g ww. Our results confirm predominance of metabolite DDE and higher-chlorinated PCB congeners and are comparable with similar studies and findings within the Czech Republic.

Expression of the multidrug resistance-associated protein 1 (MRP1) and the lung resistance-related protein (LRP) in human lung cancer.

Fifty lung cancer samples (41 non-small cell lung cancer-NSCLC and 9 small cell lung cancer-SCLC) were immunohistochemically analyzed for lung resistance-related protein (LRP) and multidrug resistance-associated protein 1 (MRP1) expressions which were then correlated with histopathological subtype of the tumor. To detect these proteins, monoclonal antibodies LRP-56 and MRPm6 were used. NSCLC samples were divided into two groups, adenocarcinomas (17 samples) and squamous cell carcinomas (24 samples). Four categories of LRP and MRP1 quantity were distinguished: +++ = high level--90--100% of positive cells, ++ = lower level--10--90% of positive cells, + = low level--up to 10% of positive cells, - = negative cells--0% of positive cells. Within the NSCLC group the most samples (36/41) had the similar level of LRP and MRP1. Significantly higher expression of both proteins was observed in the adenocarcinomas in comparison with squamous cell carcinomas. The lowest positive staining for LRP and MRP1 proteins has been found in SCLC. It is suggested that our finding can confirm the overall empirical clinical knowledge about much higher chemosensitivity of untreated SCLC comparing to NSCLC.

Langerhans cells in Langerhans cell granulomatosis are not actively proliferating cells.

Pulmonary Langerhans cell granulomatosis (LCG), also called histiocytosis X, is a disorder of unknown etiology characterized by the presence of destructive granulomas containing numerous Langerhans cells (LCs). The process may be localized or multifocal, and it remains unclear whether the same pathogenic mechanism is involved in all forms of the disease. It is often assumed that the massive accumulation of LCs at the sites of the lesions results from the abnormal proliferation of these cells, although it has been suggested that LCG in adults, at least in the lung, could be a reactive disorder initiated by activated LCs. Little is known, however, concerning the mechanisms responsible for the accumulation of large numbers of LCs in the course of the disease, and the relative contribution of recruitment and local proliferation of these cells remains to be established. To investigate this question, the proportion of replicating LCs was evaluated in biopsied granulomas from patients with localized or diffuse form of LCG by means of several histopathological techniques currently used in assessment of cell proliferation. The findings demonstrate that, except for proliferating cell nuclear antigen (PCNA), all parameters measured are low in all forms of the disease. They are similar to those of renewing epithelial cells and clearly less than those of neoplastic cells. These data strongly suggest that LCs in LCG granulomas are not a rapidly dividing cell population and that local LC replication makes only a minimal contribution to granuloma maintenance. Caution appears to be necessary in the use of PCNA as a marker of growth fraction.

[Lymphadenopathy of dermatosis in the course of drug hypersensitivity. Cytologic, immunohisto- and immunocytologic, ultrastructural aspects. Report of a case]. / Lymphadénopathie des dermatoses au cours d'une hypersensibilité médicamenteuse. Aspect cytologique, immunohisto et immunocytologique, ultrastructural. A propos d'une observation.

In addition to the morphological details obtained from the imprints, a simple immunocytological study allowed us to diagnose one case of a dermopathic lymphadenopathy simulating a T cell lymphoma, following a drug-induced erythrodermia. We were able to identify the increase of CD1a+ and Prot. S100+ cells on acetone fixed imprints. The histological, immunohistological and ultrastructural investigations confirmed the value of the cytological study and that the dendritic cells were Langerhans cells (Birbeck granules+). Most of them were considered as migrating from the dermal lesions.

[Cell proliferation in tumor pathology]. / Prolifération cellulaire en pathologie tumorale.

There are many ways to analyse and quantify the proliferating activity of a tumor. The different technics are more and more specific of each phase of the cell cycle. This paper firstly describes the basis of each of these technics (mitosis count, DNA staining with various compounds fluorescent or not, incorporation of specific molecules during the phase of DNA synthesis, detection of proliferation antigens by immunological methods). Secondly, the interest of the proliferating fraction knowledge of a tumor is discussed, for various pathologies and according to the technic used.