Vincenzo Covelli

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Pathbase is a database that stores images of the abnormal histology associated with spontaneous and induced mutations of both embryonic and adult mice including those produced by transgenesis, targeted mutagenesis and chemical mutagenesis. Images of normal mouse histology and strain-dependent background lesions are also available. The database and the(More)
Age-related alterations of the immune system affect both antibody and cell-mediated immune responses, T-cell responses being more severely affected than B-cell responses. Within the T-cell population, aging leads to replacement of virgin by memory cells and to accumulation of cells with signal transduction defects. Changes in T-cell subsets and in cytokine(More)
Loss-of-function mutations in Patched (Ptch1) are implicated in constitutive activation of the Sonic hedgehog pathway in human basal cell carcinomas (BCCs), and inherited Ptch1 mutations underlie basal cell nevus syndrome in which a typical feature is multiple BCC occurring with greater incidence in portals of radiotherapy. Mice in which one copy of Ptch1(More)
Patched1 heterozygous mice (Ptch1 1/2) are useful for basal cell carcinoma (BCC) studies, being remarkably susceptible to BCC induction by ultraviolet or ionizing radiation. Analogously, skin carcinogenesis-susceptible (CarS) mice are elective for studies of papilloma and squamous cell carcinoma (SCC) induction. We previously reported a striking effect of(More)
We described previously a basal cell carcinoma (BCC) and medulloblastoma (MB) phenotype for CD1Ptch1(neo67/+) mice exposed to ionizing radiation. Ptch1 heterozygous mice mimic the predisposition to BCC and MB development of patients affected by nevoid BCC syndrome that inherit a mutant Patched (Ptch1) allele. To examine the impact of genetic background on(More)
Two lines of mice were produced by bidirectional selective breeding: one resistant (CAR-R) and one susceptible (CAR-S) to two-stage skin carcinogenesis by dimethylbenz(a)anthracene and 12-O-tetradecanoyl-phorbol-13-acetate. The dimethylbenz(a)anthracene-DNA adduct formation was compared in the two lines by a postlabeling procedure so as to determine whether(More)
The patched (Ptc1) protein is a negative regulator of sonic hedgehog signaling, a genetic pathway whose perturbation causes developmental defects and predisposition to specific malignant tumors. Humans and mice with mutated Ptc1 are prone to medulloblastoma and basal cell carcinoma (BCC), both tumors showing dependence on radiation damage for rapid onset(More)
Biozzi MICE were obtained from an albino outbred stock by selective mating according to classical artificial selection methods, the criteria being either high (H) or low (L) antibody response to a defined immunogenic stimulus (Biozzi et al., 1975). Samples from divergent stabilized sublines were made available for lifespan and pathology observations to be(More)
This paper presents a review of several studies conducted in our laboratory to examine the carcinogenic effects in mice of high-LET radiation and, for comparison, of low-LET reference radiation. For some specific end-points the following conclusions can be formulated: i) the dose-response curves for myeloid leukemia and malignant lymphoma can be interpreted(More)
RETICULUM cell sarcoma (RCS) is observed with an average final incidence of about 57 % and appears late in the life of untreated ageing (C57BI/Cne x C3H/Cne) Fl male mice (Covelli et al., 1973). RCS is practically the only type of lymphoma developing spontaneously in animals of this strain: the total number of control mice autopsied to date is well over 400(More)