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Selina Iussich

Publications and source records attributed to Selina Iussich.

6 recordsLinked to original sources

Use of s-100 and chromogranin a antibodies as immunohistochemical markers on detection of malignancy in aortic body tumors in dog.

To define the characteristics of malignancy we performed routine histology and an immunohistochemical study on seventeen aortic body tumors in dogs. We essayed tumors using a panel of immunohistochemical markers: neuron specific enolase (NSE), chromogranin A (CrA) and S-100. Among 17 cases, the neoplastic cells were positive for NSE (17 cases, 100%), S-100 (9 cases, 53%), and CrA (8 cases, 47%), respectively. The sustentacular cells density and chief cell staining intensity were both inversely related to tumor grade. The most relevant data was consistent with a negative staining of S-100 correlated with absence or decreased number of sustentacular cells in tumors grade III. This report indicates that the immunohistochemical panel has utility for the diagnosis of chemodectoma and the negative staining to CrA and S-100 markers in tumors grade III expresses an indication of malignant behaviour of the tumor.

Age Factors↗

Spontaneous feline mammary carcinoma is a model of HER2 overexpressing poor prognosis human breast cancer.

Companion animal spontaneous tumors are suitable models for human cancer, primarily because both animal population and the tumors are genetically heterogeneous. Feline mammary carcinoma (FMC) is a highly aggressive, mainly hormone receptor-negative cancer, which has been proposed as a model for poor prognosis human breast cancer. We have identified and studied the feline orthologue of the HER2 gene, which is both an important prognostic marker and therapeutic target in human cancer. Feline HER2 (f-HER2) gene kinase domain is 92% similar to the human HER2 kinase. F-HER2-specific mRNA was found 3- to 18-fold increased in 3 of 3 FMC cell lines, in 1 of 4 mammary adenomas and 6 of 11 FMC samples using quantitative reverse transcription-PCR. Western blot showed that an anti-human HER2 antibody recognized a protein comigrating with the human p185HER2 in FMC cell lines. The same antibodies strongly stained 13 of 36 FMC archival samples. These data show that feline HER2 overexpression qualifies FMC as homologous to the subset of HER2 overexpressing, poor prognosis human breast carcinomas and as a suitable model to test innovative approaches to therapy of aggressive tumors.

Animals↗

Surgery alone versus surgery and doxorubicin for the treatment of feline injection-site sarcomas: a report on 69 cases.

Sixty-nine cats were treated for injection-site sarcomas at the Veterinary Teaching Hospital of Grugliasco, Turin (Italy). The animals were divided into two subgroups: those subjected to four doxorubicin cycles combined with radical surgical excision 10 days after the second chemotherapy cycle (group A, 49 cats) or those treated with surgery alone (group B, 20 cats). Each cat was monitored for lung metastasis and local recurrence. In group A, 28 cats were alive at the end of the follow-up period. In this group, the recurrence rate was 40.8% while lung metastasis occurred in 12% of cats. In group B, eight animals were alive at the end of the follow-up period, while the rates of recurrence and metastasis were 35% and 10%. Neither the median disease-free interval nor the median overall survival was reached in either group. Moreover, there were no statistically significant differences between the two groups.

Animals↗

Sporadic Creutzfeldt-Jakob disease: the extent of microglia activation is dependent on the biochemical type of PrPSc.

In prion-related encephalopathies, microglial activation occurs early and is dependent on accumulation of disease-specific forms of the prion protein (PrPSc) and may play a role in nerve cell death. Previously, we found that different types of PrPSc (i.e. type 1 and type 2) coexisted in approximately 25% of patients with sporadic Creutzfeldt-Jakob disease (CJD); and a close relationship was detected between PrPSc type, the pattern of PrP immunoreactivity, and extent of spongiform degeneration. To investigate whether microglial reaction is related to the biochemical type and deposition pattern of PrPSc, we carried out a neuropathologic and biochemical study on 26 patients with sporadic CJD, including all possible genotypes at codon 129 of the prion protein gene. By quantitative analysis, we demonstrated that strong microglial activation was associated with type 1 PrPSc and diffuse PrP immunoreactivity, whereas type 2 PrPSc and focal PrP deposits were accompanied by mild microglia reaction. These findings support the view that the phenotypic heterogeneity of sporadic CJD is largely determined by the physicochemical properties of distinct PrPSc conformers.

Adult↗

Evaluation of anti-prion activity of congo red and its derivatives in experimentally infected hamsters.

Among transmissible spongiform encephalopathies (TSE), particularly dreadful are the bovine spongiform encephalopathy (BSE), because of its epidemic character, and the new variant of Creutzfeldt-lakob disease (vCJD) in man, possibly related to BSE prion, through the intake of infected food. To treat TSE, many potentially therapeutic agents have been tested: some of them, among which is Congo Red (CAS 573-58-0, CR), delayed the onset of symptoms in scrapie-infected rodents, and some CR derivatives proved to be effective in vitro. The capacity of a synthesized CR derivative (CR-A) and of the aromatic central benzidine rings of CR (CR-B) to abrogate scrapie-induced disease in experimentally infected hamsters was assayed. CR, used as reference substance, administered i.c. after pre-incubation with the scrapie inoculum, was strongly effective in slowing the progression of the infection, while both CR-A and CR-B, administered alone or together, were not effective. Both CR-A and CR, when administered by subcutaneous route in i.c. scrapie-infected animals. prolonged the survival time in comparison to controls; CR-B was not effective. Moreover, both CR and CR-A were very effective in prolonging the survival time of i.p. scrapie-infected hamsters. The hypothesis of possible different mechanisms of interaction between CR or CR-A and the scrapie agent related to the chemical structures of the molecules is discussed.

Animals↗

Tetracyclines affect prion infectivity.

Prion diseases are transmissible neurodegenerative disorders of humans and animals for which no effective treatment is available. Conformationally altered, protease-resistant forms of the prion protein (PrP) termed PrP(Sc) are critical for disease transmissibility and pathogenesis, thus representing a primary target for therapeutic strategies. Based on previous findings that tetracyclines revert abnormal physicochemical properties and abolish neurotoxicity of PrP peptides in vitro, we tested the ability of these compounds to interact with PrP(Sc) from patients with the new variant of Creutzfeldt-Jakob disease (vCJD) and cattle with bovine spongiform encephalopathy (BSE). The incubation with tetracycline hydrochloride or doxycycline hyclate at concentrations ranging from 10 microM to 1 mM resulted in a dose-dependent decrease in protease resistance of PrP(Sc). This finding prompted us to investigate whether tetracyclines affect prion infectivity by using an animal model of disease. Syrian hamsters were injected intracerebrally with 263K scrapie-infected brain homogenate that was coincubated with 1 mM tetracycline hydrochloride, 1 mM doxycycline hyclate, or vehicle solution before inoculation. Hamsters injected with tetracycline-treated inoculum showed a significant delay in the onset of clinical signs of disease and prolonged survival time. These effects were paralleled by a delay in the appearance of magnetic-resonance abnormalities in the thalamus, neuropathological changes, and PrP(Sc) accumulation. When tetracycline was preincubated with highly diluted scrapie-infected inoculum, one third of hamsters did not develop disease. Our data suggest that these well characterized antibiotics reduce prion infectivity through a direct interaction with PrP(Sc) and are potentially useful for inactivation of BSE- or vCJD-contaminated products and prevention strategies.

Animals↗