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Lucio Andreassi

Publications and source records attributed to Lucio Andreassi.

15 recordsLinked to original sources
PubMed2006

Prevalence of skin allograft discards as a result of serological and molecular microbiological screening in a regional skin bank in Italy.

BACKGROUND: Postmortem skin is widely used in the treatment of patients with severe burns. Skin specimens must be screened for transmissible agents including human immunodeficiency virus (HIV), hepatitis B (HBV) and C (HCV) virus, human T-cell lymphotropic virus (HTLV), cytomegalovirus (CMV) and Treponema pallidum. METHODS: Four hundred and sixty-one cadaveric donors underwent serological and molecular microbiological (polymerase chain reaction, PCR) screening at Siena Skin Bank between 2000 and 2004. RESULTS: 74/461 donors (16.1%) were found ineligible under current regulations. CONCLUSIONS: These results are interesting in a local context and underline the importance of screening involving both routine serological procedures and molecular microbiological investigation. The latter has not been uniformly introduced in many countries and very limited data is available to assess its cost-benefit ratio in the field of skin donor screening.

Cadaver↗
PubMed2005

Autologous epidermal cultures and narrow-band ultraviolet B in the surgical treatment of vitiligo.

BACKGROUND: Vitiligo is an acquired skin disorder with a great social impact. It can be successfully treated with autologous epidermal grafting. OBJECTIVE: To evaluate the possibility of treating vitiligo by autologous grafting of epidermal cells and narrow-band ultraviolet B (UVB). METHODS: Autologous epidermal cultures were prepared starting from small biopsies of normally pigmented skin. Cells were cultured on hyaluronic acid membranes using medium supplemented with patient's serum. Cell cultures were grafted onto laser-abraded depigmented areas. Patients underwent narrow-band UVB therapy 3 weeks after grafting. RESULTS: Repigmentation of the grafted areas started 1 month after transplant and continued until 4 months after grafting. All patients were evaluated 3, 6, 12, and 18 months after grafting. At the 18-month follow-up, repigmentation was observed in 75% of patients with focal and segmental vitiligo and in 30% of patients with generalized vitiligo. CONCLUSIONS: This therapy can be considered for the treatment of stable vitiligo (especially focal and segmental) resistant to standard therapies. Their results are encouraging from the clinical and esthetic point of view, although the treatment is costly and highly specialized.

Adolescent↗
PubMed2004

Melanoma computer-aided diagnosis: reliability and feasibility study.

BACKGROUND: Differential diagnosis of melanoma from melanocytic nevi is often not straightforward. Thus, a growing interest has developed in the last decade in the automated analysis of digitized images obtained by epiluminescence microscopy techniques to assist clinicians in differentiating early melanoma from benign skin lesions. PURPOSE: The aim of this study was to evaluate diagnostic accuracy provided by different statistical classifiers on a large set of pigmented skin lesions grabbed by four digital analyzers located in two different dermatological units. EXPERIMENTAL DESIGN: Images of 391 melanomas and 449 melanocytic nevi were included in the study. A linear classifier was built by using the method of receiver operating characteristic curves to identify a threshold value for a fixed sensitivity of 95%. A K-nearest-neighbor classifier, a nonparametric method of pattern recognition, was constructed using all available image features and trained for a sensitivity of 98% on a large exemplar set of lesions. RESULTS: On independent test sets of lesions, the linear classifier and the K-nearest-neighbor classifier produced a mean sensitivity of 95% and 98% and a mean specificity of 78% and of 79%, respectively. CONCLUSIONS: In conclusion, our study suggests that computer-aided differentiation of melanoma from benign pigmented lesions obtained with DB-Mips is feasible and, above all, reliable. In fact, the same instrumentations used in different units provided similar diagnostic accuracy. Whether this would improve early diagnosis of melanoma and/or reducing unnecessary surgery needs to be demonstrated by a randomized clinical trial.

Diagnosis, Computer-Assisted↗
PubMed2004

Digital surface microscopy analysis of conjunctival pigmented lesions: a preliminary study.

The objective of this study was to investigate whether digital surface microscopy (DSM) could be used for the follow-up and comparison of malignant and benign conjunctival pigmented lesions (CPLs). Thirty-nine CPLs [16 de novo malignant melanomas (MMs), one MM arising from primary acquired melanosis (PAM), six PAMs and 16 naevi] were digitally analysed and biopsied. All of the PAMs and 10 naevi, which had not been surgically excised, were followed up using DSM. Thirty parameters were evaluated grouped into four categories: geometry, colour, texture and islands of colour. None of the CPLs that were followed up, which comprised 10 naevocytic naevi and seven PAMs, showed any morphological change at DSM analysis, except for one PAM which developed an MM 1 year later. Of the geometric variables examined, the area, maximum diameter and minimum diameter showed significantly higher values in MMs compared with benign CPLs. With regard to the colour of CPLs, MMs were significantly darker and bluer than naevi. In the texture group, contrast was significantly higher in MMs. In the islands-of-colour group, the imbalance of blue-grey regions and the presence of dark areas were significantly higher in MMs. DSM greatly simplified the follow-up of CPLs, such as PAMs with atypia, by providing satisfactory quality images with high reproducibility; this technique is also easy to use and well accepted by patients. Moreover, this preliminary study allowed us to determine which objective variables could be important for distinguishing between benign CPLs and conjunctival MMs.

Adolescent↗
PubMed2004

Inter- and intra-variability of pigmented skin lesions: could the ABCD rule be influenced by host characteristics?

BACKGROUND/PURPOSE: Many differences in color, shape and dimension exist between different moles even in the same individual. Major differences might be accounted for anatomical location, genetic factors and by environmental factors, mainly sunlight exposure. Therefore, it would be of great value, when evaluating skin lesions, to take into account the degree of intra- and inter-variability of several diagnostic parameters. In order to assess the morphologic and chromatic differences between lesions belonging to different patients and between lesions belonging to the same individual, we examined objective digital parameters obtained with dermatoscopic analysis, using the DBDermo MIPS system (BIO MIPS Engineering, S.R.L, siena, Italy). METHODS: The automatic classifier inside the software is based on a 'match by similarity' algorithm, based on the measurement of the Euclidean distances of all variables considered from the reference image. Two-hundred and four clinically benign pigmented lesion, belonging to 18 patients were examined, stored and automatically processed. For each lesion objective parameters related to geometry, color and texture were automatically evaluated. RESULTS: We found skin color (healthy skin) is objectively different from subject to subject and the lesion color is more similar among different lesions of the same patient than among lesions belonging to different individuals both in their darkest and slightly dark component. We also observed that lesion dimensions are individual correlates, i.e. the probability for a lesion to be large is higher when the other, in the same patient, is large. CONCLUSION: Many parameters of pigmented skin lesions evaluated by digital dermoscopy analysis are similar in the same patient and different from those belonging to different individuals. This indicates that, when considering a lesion, we should take into account the peculiar patient's characteristics.

Diagnosis, Computer-Assisted↗
PubMed2003

Involvement of oxidative stress in apoptosis induced by a mixture of isothiazolinones in normal human keratinocytes.

A 3:1 combination of 5-chloro-2-methyl-4-isothiazolin-3-one (CMI) and 2-methyl-4-isothiazolin-3-one (MI) is widely used to preserve cosmetic products. We show here that CMI/MI induced apoptosis in normal human keratinocytes (NHK) as at low concentrations (0.001-0.05% documented by subdiploid DNA content and phosphatidylserine exposure, while at the highest concentration (0.1% as supplied, 15 p.p.m.) the response was necrosis. Various molecular events accompanied the cytotoxic effects of CMI/MI. Generation of ROS and hyperpolarization of mitochondrial transmembrane potential (DeltaPsim) were early events, followed by increased Fas expression and activation of caspase-8, and then activation of caspase-3 and -9. The drop in DeltaPsim occurred only later in the cell death pathway, when NHK showed signs of apoptosis. Pretreatment of cells for 2 h with the redox-active agent N-acetyl-L-cysteine conferred complete protection against the CMI/MI-induced cytotoxic effects, DeltaPsim loss, and apoptosis. The pan-caspase inhibitor Z-Val-Ala-Asp(OMe)-CH2F blocked the CMI/MI-induced apoptosis without preventing ROS generation and the drop in DeltaPsim. These results indicate that the generation of ROS plays an important part in mediating apoptosis and necrosis associated with CMI/MI treatment. This new aspect of the in vitro toxicity of CMI/MI may provide important information about the relationship between the preservative's in vitro apoptotic activity and its in vivo toxicity.

Amino Acid Chloromethyl Ketones↗
PubMed2002

Automated diagnosis of pigmented skin lesions.

Since advanced melanoma remains practically incurable, early detection is an important step toward a reduction in mortality. High expectations are entertained for a technique known as dermoscopy or epiluminescence light microscopy; however, evaluation of pigmented skin lesions by this method is often extremely complex and subjective. To obviate the problem of qualitative interpretation, methods based on mathematical analysis of pigmented skin lesions, such as digital dermoscopy analysis, have been developed. In the present study, we used a digital dermoscopy analyzer (DBDermo-Mips system) to evaluate a series of 588 excised, clinically atypical, flat pigmented skin lesions (371 benign, 217 malignant). The analyzer evaluated 48 parameters grouped into 4 categories (geometries, colors, textures and islands of color), which were used to train an artificial neural network. To evaluate the diagnostic performance of the neural network and to check it during the training process, we used the error area over the receiver operating characteristic curve. The discriminating power of the digital dermoscopy analyzer plus artificial neural network was compared with histologic diagnosis. A feature selection procedure indicated that as few as 13 of the variables were sufficient to discriminate the 2 groups of lesions, and this also ensured high generalization power. The artificial neural network designed with these variables enabled a diagnostic accuracy of about 94%. In conclusion, the good diagnostic performance and high speed in reading and analyzing lesions (real time) of our method constitute an important step in the direction of automated diagnosis of pigmented skin lesions.

Automation↗
PubMed2002

Digital dermoscopy analysis and artificial neural network for the differentiation of clinically atypical pigmented skin lesions: a retrospective study.

Noninvasive diagnostic methods such as dermoscopy or epiluminescence light microscopy have been developed in an attempt to improve diagnostic accuracy of pigmented skin lesions. The evaluation of the many morphologic characteristics of pigmented skin lesions observable by epiluminescence light microscopy, however, is often extremely complex and subjective. With the aim of obviating these problems of qualitative interpretation, methods based on mathematical analysis of pigmented skin lesions have recently been designed. These methods are based on computerized analysis of digital images obtained by epiluminescence light microscopy. In this study we used a digital dermoscopy analyzer with 147 clinically atypical pigmented skin lesions (90 nevi and 57 melanomas) to determine its discriminating power with respect to histologic diagnosis. The system evaluated 48 objective parameters used to train an artificial neural network. Using the artificial neural network with 10 variables selected by a stepwise procedure, we obtained a maximum accuracy in distinguishing melanoma from benign lesions of about 93%. Comparing this result with those of the many studies using classical epiluminescence light microscopy, it emerges that the method proposed is equal or even superior in diagnostic accuracy and has the advantage of not depending on the expertise of the clinician who examines the lesion.

Humans↗
PubMed2002

UVA light stimulates the production of cathepsin G and elastase-like enzymes by dermal fibroblasts: a possible contribution to the remodeling of elastotic areas in sun-damaged skin.

Solar elastosis is characterized by accumulation of large amounts of material staining similarly to elastin in the dermis. The nature of this material and the process responsible for its accumulation are still unknown. Elastolytic proteases have important functions in the catabolism of the interstitial matrix and can also generate, by the digestion of the interstitial proteins, soluble peptides which can induce collagen and elastin synthesis and deposition. We investigated whether (i) elastolytic enzymes can be detected in samples from sun-exposed and non-exposed skin, and (ii) ultraviolet (UV) rays influence the production of elastolytic activities in cultured dermal fibroblasts. Immunoelectron microscopy showed a positive reaction for neutrophil elastase and cathepsin G in fibroblast-like cells from specimens of sun-exposed areas. Little or no reaction was found in biopsies of sun-protected skin. Fibroblast cultures from sun-exposed skin expressed higher levels of hydrolytic activity against synthetic substrates of elastases and cathepsin G than those obtained from sun-protected areas. Irradiation with UVA strongly stimulated the production of these activities in fibroblasts from sun-protected sites. No significant change was detected in parallel sets of cultures after UVB irradiation. Inhibition experiments indicated that the elastase-like activity expressed by fibroblasts can be attributed to at least two enzymes.

Aged↗
PubMedDate not supplied

Autografts and cultured epidermis in the treatment of vitiligo.

Skin transplants can be a useful and efficacious method to treat vitiligo. The aim is to repopulate areas lacking melanocytes with functional cells taken from normally pigmented areas. Several procedures have been devised and tested: some consist in the simple transfer of epidermis sampled and implanted as is, whereas others are based on the transplantation of disaggregated and manipulated cells. The therapeutic success of the former methods is partly determined by the ability and experience of the surgeon performing the operation, whereas the results of the latter methods mainly depend on the laboratory facilities and abilities of the personnel who manipulate the cells to be transplanted. The transplantation of cultured cells is the most fascinating and promising procedure but requires the observance of still not completely predictable procedures. The use of biological material of animal origin and the use of factors to stimulate cell proliferation, such as growth factors and promoting agents, are other points that require attention.

Culture Techniques↗
PubMedDate not supplied

Reality and fantasies: the psychology of skin transplants.

Skin transplants present similarities with and differences from other organ transplants (heart, kidney, liver) in the psychological sphere and in regard to symbolic and mythological references. A brief story supplies some explanations and introduces the reader to information in the psychosomatic and psycholinguistic spheres in scientific literature. We also present a list of commonly used terms that include the word skin, and cite important literary references that have some relationship with the subject of skin transplants, all to emphasize and explain why/how this topic is so emotionally involving.

History, 19th Century↗
PubMedDate not supplied

Maurizio Binazzi.

Explore the source record for details and available documents.

Dermatology↗
PubMedDate not supplied

Skin cancer day in Italy: method of referral to open access clinics and tumor prevalence in the examined population.

Education campaigns to encourage self-examination coupled with rapid access to specialized dermatological clinics is considered the key strategy in the realization of early detection of cutaneous melanoma and non-melanoma skin cancer (NMSC). An alternative to an initial visit to the family doctor is open access to a skin cancer clinic at the decision of the individual. This approach has been followed mainly in countries with high melanoma incidence where the majority of the population is of northern European origin. However, the efficacy of this system has not been well established because there are few studies involving systematic follow up of individuals with positive screening through pathological confirmation of the diagnosis. We report the follow up data focussed on melanoma and NMSC detection rates in more than 1,000 subjects examined at numerous 1-day, open access clinics on the occasion of the Italian nation-wide "Skin Cancer Day" campaign promoted by the Federation of Italian Dermatological Societies. Total body skin examination was performed on all subjects, and surgical excision of a lesion was recommended in 41 of the 1042 subjects (3.9 %). Histologic diagnosis, available for 39/41 lesions, evidenced 3 superficial spreading melanomas (1 in situ, one "thin" lesion, ie. 0.30 mm in thickness, and one "thick" lesion, with a thickness of 4.53 mm) and 6 NMSC (5 BCC and 1 SCC). Thus, the prevalence of skin cancer (melanoma and NMSC) in this group was 0.8 % (9/1042), and the prevalence of melanoma was 3/1042, 0.2 %, rather similar to that found in populations of northern European origin. Open access to skin cancer clinics may represent an alternative approach to melanoma prevention also in southern European populations. Increased public awareness regarding skin cancer probably represents the main effect of this type of campaign.

Adult↗