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Dive into the research topics where Franca Piras is active.

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Featured researches published by Franca Piras.


Cancer | 2005

The predictive value of CD8, CD4, CD68, and human leukocyte antigen-D-related cells in the prognosis of cutaneous malignant melanoma with vertical growth phase.

Franca Piras; Romano Colombari; Luigi Minerba; Daniela Murtas; Carlo Floris; Cristina Maxia; Arianna Corbu; M. Teresa Perra; P. Sirigu

To establish the prognostic value of immune system cells that infiltrate melanoma, the authors evaluated the distribution and density of T lymphocyte subsets, macrophages, and dendritic cells in samples of primary cutaneous melanoma from 47 patients with Stage I and II melanoma according to the American Joint Committee on Cancer staging system.


British Journal of Ophthalmology | 2003

Detection of human papillomavirus DNA in pterygia from different geographical regions

Franca Piras; Ps Moore; J Ugalde; Maria Teresa Perra; Aldo Scarpa; P. Sirigu

Background/aims: The aetiology and pathogenesis of pterygia remain unclear and the involvement of human papillomavirus (HPV) is controversial. 41 pterygia from two geographic locations were evaluated for the presence of HPV DNA. Methods: 41 pterygium biopsies (17 from Italy and 24 from Ecuador) were analysed using the L1C1 and PU-1ML primer sets by polymerase chain reaction (PCR) and DNA sequence analysis. Results: 22 of the 41 pterygia (54%) were positive for HPV, including all 17 Italian cases and 5/24 (21%) Ecuadorean cases. DNA sequencing of the 22 positive cases showed that 11 were HPV type 52, four were type 54, five were candHPV90, and two of unknown genotype. Conclusions: The major differences in the frequency of HPV in geographically distant populations might suggest a possible explanation for the vast differences in the reported detection rates. Three subtypes of HPV were found in this sample of pterygia. None the less, these results suggest that HPV may have a pathogenic role in pterygium.


Histopathology | 2007

Nuclear survivin is associated with disease recurrence and poor survival in patients with cutaneous malignant melanoma

Franca Piras; Daniela Murtas; Luigi Minerba; J Ugalde; C Floris; Cristina Maxia; R Colombari; Maria Teresa Perra; P. Sirigu

Aims:  Survivin is expressed in neoplastic cells and appears to be associated with resistance to therapy and shorter survival in various types of tumours. The aim of the present study was to determine whether nuclear or cytoplasmic expression of survivin is related to disease recurrence and overall survival of patients with Stage I and II melanoma according to the American Joint Committee on Cancer (AJCC) staging system.


Virology Journal | 2011

Prevalence of human papillomavirus infection in women in Benin, West Africa

Franca Piras; Michela Piga; Antonella De Montis; Ahissou Rf Zannou; Luigi Minerba; Maria Teresa Perra; Daniela Murtas; Manuela Atzori; Marco Pittau; Cristina Maxia; P. Sirigu

BackgroundCervical cancer ranks as the first most frequent cancer among women in Benin. The major cause of cervical cancer now recognized is persistent infection of Human Papillomavirus (HPV). In Benin there is a lack of screening programs for prevention of cervical cancer and little information exists regarding HPV genotype distribution.MethodsCervical cells from 725 women were examined for the presence of viral DNA by means of a polymerase chain reaction (PCR) multiplex-based assay with the amplification of a fragment of L1 region and of E6/E7 region of the HPV genome, and of abnormal cytology by Papanicolaou method. The association between HPV status and Pap test reports was evaluated. Socio-demographic and reproductive characteristics were also related.ResultsA total of 18 different HPV types were identified, with a prevalence of 33.2% overall, and 52% and 26.7% among women with and without cervical lesions, respectively. Multiple HPV infections were observed in 40.2% of HPV-infected women. In the HPV-testing group, the odds ratio for the detection of abnormal cytology was 2.98 (95% CI, 1.83-4.84) for HPV positive in comparison to HPV negative women. High risk types were involved in 88% of infections, most notably HPV-59, HPV-35, HPV-16, HPV-18, HPV-58 and HPV-45. In multiple infections of women with cytological abnormalities HPV-45 predominated.ConclusionsThis study provides the first estimates of the prevalence of HPV and type-specific distribution among women from Benin and demonstrates that the epidemiology of HPV infection in Benin is different from that of other world regions. Specific area vaccinations may be needed to prevent cervical cancer and the other HPV-related diseases.


Journal of Cellular and Molecular Medicine | 2007

Neovascularization and mast cells with tryptase activity increase simultaneously in human pterygium.

Domenico Ribatti; Beatrice Nico; Cristina Maxia; Vito Longo; Daniela Murtas; Domenica Mangieri; M. Teresa Perra; Michela De Giorgis; Franca Piras; Enrico Crivellato; P. Sirigu

Mast cells (MC) have been implicated in both normal and pathological angiogenesis, such as that in chronic inflammatory diseases and tumors. This assumption is partially supported by the close structural association between MC and blood vessels and the recruitment of these cells during tumor growth. MC release a number of angiogenic factors among which tryptase, a serine protease stored in MC granules, is one of the most active. In this study, we correlate the extent of angiogenesis with the number of tryptase‐reactive MC in tissue fragments from pterygium and normal bulbar conjunctiva investigated by immunohistochemistry, using two murine monoclonal antibodies against the endothelial cell marker CD31 and the MC marker tryptase. Angiogenesis, measured as microvessel density, was highly correlated with MC tryptase‐positive cell count in pterygium tissues. These results suggest that the characteristic neovascularization observed in pterygium may be sustained, at least in part, by MC angiogenic mediators, in particular tryptase.


Journal of Cellular and Molecular Medicine | 2008

Expression of survivin protein in pterygium and relationship with oxidative DNA damage

Cristina Maxia; Maria Teresa Perra; Paolo Demurtas; Luigi Minerba; Daniela Murtas; Franca Piras; Arianna Corbu; Dc Gotuzzo; Rg Cabrera; Domenico Ribatti; P. Sirigu

Ultraviolet radiation is known to cause oxidative DNA damage and is thought to be a major factor implicated in the pathogenesis of pterygium. Among all the photo‐oxidative DNA products, the 8‐hydroxydeoxyguanosine (8‐OHdG) is regarded a sensitive and stable biomarker for evaluating the degree of DNA damage. The protein p53 is a major cell stress regulator that acts to integrate signals from a wide range of cellular stresses. UV radiation has a carcinogenic effect resulting in DNA damaged cells with loss of normal growth control. This assumption is supported by the association between UV‐B exposure and activation of survivin, a member of the inhibitor of apoptosis protein family (IAP), highly up‐regulated in almost all types of human malignancy. In this study we demonstrate, for the first time in pterygium, the immunohistochemical presence of survivin, and investigate the correlation between survivin, p53 and 8‐OHdG. Our results demonstrate that oxidative stress could lead to a significant activation of survivin expression, suggesting that this might be an important event in the development of pterygium, inducing and supporting a hyperproliferative condition. Survivin expression in pterygium would counteract UV‐B‐induced apoptosis and would cooperate with loss of p53. The co‐operation between survivin and functional loss of p53 might provide a general mechanism for aberrant inhibition of apoptosis that could be responsible for the development of pterygium and its possible progression to neoplasia.


International Journal of Experimental Pathology | 2010

Erythropoietin is involved in angiogenesis in human primary melanoma

Domenico Ribatti; Beatrice Nico; Maria Teresa Perra; Vito Longo; Cristina Maxia; Tiziana Annese; Franca Piras; Daniela Murtas; P. Sirigu

In this study, the extent of angiogenesis, evaluated as microvascular volume density, immunoreactivity of tumour cells to erythropoietin (Epo) and of endothelial cells to Epo receptor (EpoR) have been correlated in human primary melanoma specimens. Results showed that Epo/EpoR expression correlate with angiogenesis and tumour thickness. These findings suggest that Epo is secreted by tumour cells and it affects vascular endothelial cells via its receptor and promotes angiogenesis in a paracrine manner, playing an important role in melanoma angiogenesis.


International Journal of Experimental Pathology | 2009

Correlation between NGF/TrkA and microvascular density in human pterygium

Domenico Ribatti; Beatrice Nico; Maria Teresa Perra; Cristina Maxia; Franca Piras; Daniela Murtas; Enrico Crivellato; P. Sirigu

Pterygium is a surface ocular lesion that is associated with chronic UV exposure. The primary effect is a solar actinic elastosis within the stroma. All the other changes are secondary. Pterygium is characterized by proliferation, inflammatory infiltrates, fibrosis, angiogenesis and extracellular matrix breakdown. The aim of this study was to correlate microvascular density and nerve growth factor (NGF)/NGF‐receptor transmembrane tyrosine kinase (TrkA) expression in endothelial cells in human pterygium. Specimens of human pterygium obtained from 30 patients who had undergone surgical excision and of 10 normal bulbar conjunctiva were investigated immunohistochemically by using anti‐CD31, anti‐NGF and anti‐TrkA antibodies. Results showed that endothelial cells in human pterygium are immunoreactive to both NGF and its receptor TrkA, and that this immunoreactivity is correlated to microvascular density. The results of this study suggest that an autocrine loop between NGF and its receptor TrkA is activated in pterygium and that it is involved in the angiogenic response taking place in this pathological condition. These data are in accord with recent evidences, which have clearly established that NGF plays a role as an angiogenic factor in several pathological conditions. Understanding the mechanism of angiogenesis in pterygium provides a basis for a rational approach to the development of anti‐angiogenic therapy in patients affected by this disease.


Histopathology | 2006

Finding of conjunctival melanocytic pigmented lesions within pterygium

Maria Teresa Perra; R Colombari; Cristina Maxia; Ignazio Alberto Zucca; Franca Piras; Arianna Corbu; S Bravo; Aldo Scarpa; P. Sirigu

Aims : Conjunctival pigmented lesions have characteristic clinical and histopathological appearances. Melanocytic pigmented lesions commonly occur in the conjunctiva, although they have not been previously reported in pterygium, a common lesion which originates from conjunctiva. Our aim was to evaluate the possibility of an association between pterygium and conjunctival melanocytic pigmented lesions.


Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology | 2007

A morphological and 13C NMR study of the extramandibular fat bodies of the striped dolphin (Stenella coeruleoalba).

Cristina Maxia; Paola Scano; Federica Maggiani; Daniela Murtas; Franca Piras; Roberto Massimo Crnjar; Adolfo Lai; P. Sirigu

The molecular and histological structure of the fat bodies covering externally the posterolateral region of the jaw of the striped dolphin (Stenella coeruleoalba) was investigated by means of morphological and nuclear magnetic resonance techniques. The analyses of samples belonging to adult and juvenile individuals were performed with the aim of seeking the presence of age‐related differences. In our study, the level of isovalerate (iso5:0) in the extramandibular fat of the juvenile individuals is comparable with those of the adult counterparts; conversely, longer isobranched fatty acids were detected in lower quantities in the juveniles together with a higher degree of unsaturation. The morphologic analyses revealed that, in both adults and juveniles, this fatty tissue is similar to univacuolar adipose tissue. However, in the juveniles, a muscular component was present, whereas only in adult subjects, enlarged and irregularly shaped cavities may be seen within the adipose tissue. These cavities, structurally organized as veins, may regulate blood flow in response to changing water temperature and stabilize thermal gradient within the jaw lipids. These data suggest that the molecular components and the histological organization can indicate a maturation of the organ with age that probably may reflect different sound reception properties. Anat Rec, 2007.

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P. Sirigu

University of Cagliari

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S Lai

University of Cagliari

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