1,720,973 research outputs found
Molecular genetic aspects of cutaneous melanoma
No full textThe etiopathogenesis of cutaneous melanoma has been correlated to both genetic and environmental factors. During the last decade, molecular-genetic studies have demonstrated that high-penetrance genes such as cyclin-dependent kinase inhibitor 2A (CDKN2A) and cyclin-dependent kinase (CDK4), and low-penetrance genes such as MC1R play an important role in the pathogenesis of melanoma. CDKN2A and CDK4 genes function as cell cycle regulators, while MC1R gene is an important determinant of cutaneous pigmentation. Several studies have emphasized that CDKN2A gene, a tumor suppressor gene located at 9p21, has a crucial role in the development of familial, multiple and sporadic melanoma. Germline mutations of the CDKN2A gene have been identified in approximately 25-40% of familial melanoma kindreds worldwide and in 8-20% of patients with multiple primary melanoma (MPM). In contrast, somatic mutations of the CDKN2A gene have been frequently identified in sporadic melanoma. Mutations of the CDK4 oncogene have been described at a low frequency in familial and sporadic melanoma, and no alterations have been identified in patients with MPM. Recent studies showed that specific allelic variants of the MC1R gene confer susceptibility to melanoma and modify the risk of developing melanoma in patients who harbor CDKN2A mutations. Finally, based on the low number of studies, it is not yet clear the precise role of some putative oncogene or tumor suppressor genes located on chromosomes 1, 6, 7, 10, 11 and 17, which have been previously shown to be altered in cutaneous melanoma
Efficacy, tolerability, and cosmetic outcome of MAL-PDT in the treatment of basal cell carcinoma
No full text
Efficacy of photodynamic therapy with methyl aminolevulinate in the treatment of superficial and nodular basal cell carcinoma: an open-label trial
No full textPhotodynamic therapy with methyl aminolevulinate (MAL-PDT) is a non-invasive therapy for superficial and nodular basal cell carcinoma (BCC). We performed an open-label trial to evaluate efficacy, safety, tolerability and cosmetic outcome of MAL-PDT in selected patients with superficial and nodular BCCs. Ninety-four superficial and 24 nodular BCCs in 69 patients were treated with 2 to 8 MAL-PDT sessions. Efficacy, safety, tolerability and cosmetic outcome were evaluated at months 1, 3, 6 and 12 after the last MAL-PDT treatment and then every 3 months. One patient discontinued the study for reasons unrelated to study procedures. Complete clinical regression was detected in 84/94 (89.4%) superficial BCCs, and 12/23 (52.2%) nodular BCCs one month after 2 MAL-PDT sessions. No further clinical improvement was observed in either superficial or nodular BCCs with treatment continuation up to a maximum of 8 MAL-PDT sessions. Adverse effects were limited to mild local skin reactions, and cosmetic outcome was rated as excellent or good. Recurrence was observed in 2/84 (2.4%) successfully treated superficial BCCs at 6 and 12 months after treatment discontinuation. Based on the efficacy, tolerability, cosmetic outcome and recurrence rate, our results support the use of MAL-PDT for treatment of superficial BCC and for selected cases of nodular BCC
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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