SKH-1 mouse skin painting: a short-term assay to evaluate the tumorigenic activity of cigarette smoke condensate.

The hairless mouse strain SKH-1 was investigated in a short-term assay to assess the tumorigenic activity of mainstream cigarette smoke condensate (CSC). The design chosen was the two-stage dermal tumorigenicity assay (skin painting), with tumor initiation using a single dermal application of the carcinogen/mutagen dimethylbenz(a)anthracene applied to the back at a non-tumorigenic dose and tumor promotion by repeated dermal applications of CSC at the same site. The mice reproducibly developed skin tumors at the application site after 15 weeks at a frequency that allowed comparison of the treatment groups. The histopathological examination revealed the benign nature of the tumors (keratotic papillomas). Prolongation of the application period to 25 weeks resulted in the development of malignant tumors (carcinomas), indicating that the benign tumors after 15 weeks can be taken as surrogate endpoints for malignancies progressing after further treatment. After 15 weeks, tumor incidence (the percentage of tumor-bearing mice), tumor multiplicity (the number of tumors per mouse), and tumor-onset (the duration of the application period that resulted in a meaningful tumor incidence) were positively correlated with the initiating and promoting dose. The reproducibility of this assay was at least comparable to that described for other skin painting models in the literature. When the assay system was used to compare CSCs to which different concentrations of benzo(a)pyrene were added, its ability to distinguish these different condensate preparations was comparable to that of other models. The results obtained with the SKH-1 mouse strain suggest its usefulness in the short-term skin painting assay for the comparative investigation of the tumorigenic activity of different CSCs.

[Contribution of enzyme-linked immuno-electrotransfer blot assay for the diagnosis of human neurocysticercosis]. / Apport de l'enzyme-linked immunoelectrotransfer blot assay au diagnostic de la neurocysticercose humaine.

An enzyme-linked immunoelectrotransfer blot (EITB) is developed for immunodiagnosing human neurocysticercosis. The assay's efficacy is evaluated in 71 neurocysticercotic patients whose diagnosis of the disease and evaluation of disease activity is based on CT scan findings. We identified eight bands (molecular weigh less than 35 000) that evaluate the disease activity: active disease, calcification in progress, inactive disease. All samples patients with active disease recognized 14 000 band. This band is missing in the others parasitic diseases and in serum of the patients with inactive diseases or calcification in progress. The enzyme-linked immunoelectrotransfer blot is simple to perform and may be used in sero-epidemiology.

[Immunologic diagnosis of the cerebrospinal fluid and serum in developing brain cysticercosis]. / Diagnostic immunologique dans le liquide céphalo-rachidien et le sérum de la cysticercose encéphalique évolutive.

ELISA detection of specific antibodies in the serum (IgG) and cerebrospinal fluid (IgG, IgM and IgA) was evaluated in 28 patients. Diagnosis of cerebral cysticercosis and evaluation of disease activity was based on CT scan findings. Specific IgG antibodies were found in the serum in 83.3% of patients with active disease and 10% of those with inactive disease. Cerebrospinal fluid tests evidenced specific antibodies in all patients with active disease and none of the patients with inactive disease. The specific CSF antibodies were IgG (94.4%), IgM (66.6%) or IgA (66.6%). Antibody titers were significantly higher in patients with an intraventricular vesicle or cyst.

[Racemous cysticercosis of the cauda equina and cystic arachnoiditis. Apropos of 2 cases]. / Cysticercose racemeuse de la queue de cheval et arachnoidite kystique. A propos de deux cas.

Central nervous system infection by the larval form of the pork tapeworm, taenia solium is a major public health problem in view of its prevalence. The high incidence of neurocysticercosis in Reunion Island has been precised by computerized tomography and Elisa test. Spinal involvement is an uncommon form of cysticercosis, occurring with a frequency of less than 1% in large series. The types of involvement that are most common are subarachnoid cysts which appear as intradural extramedullary masses and meningeal reaction with appearance of arachnoiditis at myelography. Intramedullary involvement is less frequent. Epidural and subpial masses have been reported very rarely. The authors report the two first cases of spinal cysticercosis in Reunion Island which are both extramedullary leptomeningeal forms. A radicular syndrome was present in both cases; incontinence and sacral hemihypoesthesia in one case. Myelography showed lumbosacral arachnoid cysts. Immunodiagnostic tests were positive in blood and C.S.F. in the two cases. Laminectomy was performed and the arachnoid membrane appeared opaque and thickened; the cysts were removed. Microscopically the cystic wall had a thin and curved cuticle, no scolex was found. Treatment was completed with the anti-helminthic agent Praziquantel. Full recovery was observed in one case. In the other case low back pain spread out to the lower extremities with a non radicular distribution and was associated with lumbosacral spinal fibrosis.

[Epidemiologic survey of the cysticercosis endemic on Réunion Island]. / Enquête épidémiologique sur l'endémie cysticerquienne à la Réunion.

The high incidence of cysticercosis was underestimated in Reunion Island before computed tomography (January, 1984). In 1974, Soulayrolles et Boyer-Vidal found that cysticercosis was responsible for 0.5 p. 100 of the cases of epilepsy. In hospitalized people, routine cranial and muscles radiographies detected: 1/among 242 epileptics: 183 men: 36 positive (19.67 p. 100); 59 women: 9 positive (15.25 p. 100), 2/among 166 non epileptic-related neurological disorders: 106 men, 6 positive (5.66 p. 100), 60 women: 6 positive (8.33 p. 100); 3/among 219 hospitalized patients with no neurological diseases: 124 men: 18 positive (14.5 p. 100), 95 women: 2 positive (2.10 p. 100). The clinical features of cysticercosis are so various that it appears impossible to define a typical clinical presentation. On the other hand the diagnosis is easy with CT scan and a serodiagnostic test (Elisa). In 98 patients, clinical symptoms and signs, CT scan and serology (Elisa) have been evaluated. Praziquantel was introduced in 1984 with good results as judged by serial CT scans. A human and animal investigation has been set up to define more clearly the relationship between the human parasitosis and rearing of domestic pigs to try to eradicate human and animal cysticercosis in Reunion Island.