Protein kinase Cgamma autoimmunity in paraneoplastic cerebellar degeneration and non-small-cell lung cancer.

BACKGROUND: The clinical and immunological profiles of patients with paraneoplastic cerebellar degeneration (PCD) and non-small-cell lung cancer (NSCLC) are not well known. OBJECTIVE: To review the clinical and immunological features of patients with PCD, NSCLC and without well-characterised onconeural antibodies. METHODS: The clinical features of nine patients with the diagnosis of classical PCD and NSCLC, included in our archives, were retrospectively reviewed. The presence of antibodies to cerebellar components was determined by immunohistochemistry and immunoblot of rat cerebellum. A cDNA library of human cerebellum was screened with the positive sera to identify the antigen. RESULTS: Nine patients with PCD and NSCLC were identified. Six patients were men, and the median age at diagnosis of PCD was 63 (range 47-73) years. PCD was completely reversed in two patients, and partially in one, after treatment of the tumour. The serum of one of the patients with PCD showed a unique reactivity with Purkinje cells. The screening of a cerebellar-expression library resulted in the isolation of protein kinase Cgamma (PKCgamma). PKCgamma immunoreactivity was not observed in the serum of 170 patients with non-paraneoplastic neurological syndromes, 27 patients with PCD, no onconeural antibodies and small-cell lung cancer, and 52 patients with NSCLC without paraneoplastic neurological syndromes. The NSCLC from 11 patients without PCD did not express PKCgamma at either the RNA or protein level. However, many cells of the NSCLC of the patient with PKCgamma antibodies expressed PKCgamma. CONCLUSION: PCD occurs in patients with NSCLC without typical onconeural antibodies and is associated with immune reactions against key proteins of the Purkinje cells.

[In vitro sensitivity of Entamoeba histolytica to metronidazole]. / Sensibilidad in vitro de Entamoeba histolytica a Metronidazol.

The chemotherapy of amebiasis includes different substances with intra and extraintestinal action. Nowadays, metronidazole is the election drug by its high efficacy and low toxicity. Some therapeutic failures with metronidazole in patients with invader amebiasis and some reports of resistance to it, of certain strains of Trichomonas vaginalis and species of Bacteroides have caused an increased interest to do new in vitro evaluation of this compound and to search of new antiamebic drugs. The object of this work was to standardize with our conditions a microtechnique to evaluate the sensibility to metronidazole, experimented by trophozoites of three amebic strains of different virulence (HK9:NIH, HM1:IMSS, HM3:IMSS) and to compare the effect exerted by the drug on them. We modified the technique proposed by Cedeño and Krogstad in 1983. First we read the results in a half of the time employed by them (24h) and after, we fixed the trophozoites with 0.25% glutaraldehyde before of make the counts of them. We compared the number of cells in microcultures of 3.2 x 10(4) trophozoites incubated during 24h with metronidazole (from 0.008 to 1 micrograms/ml) with the obtained in control microcultures. Each one of the strains showed to have a characteristic sensibility to the drug (p less than 0.001), which was directly proportional to the concentration. The middle effective dose of HK9 and HM1 strains was 0.3 microgram/ml and of 1 microgram/ml for HM3 strain. This technique seems to be reproducible and could be useful to quantify the in vitro activity of antiamebic agents.