Thy-1 as a potential novel diagnostic marker for gastrointestinal stromal tumors

Purpose Only few immunohistochemical markers besides c-kit exist for gastrointestinal stromal tumors (GISTs). Thy-1, a cell-surface glycoprotein, is a marker for several types of stem cells and particularly for neuronal precursor cells. The aim of this study was to determine Thy-1 expression in GISTs. Materials and methods Fifty-seven surgically resected and paraffin-embedded GIST samples were analyzed by immunohistochemistry with peroxidase method for Thy-1 molecule. Results Thy-1 was detected in the majority of 57 GIST samples (54 out of 57 patients, 95%). All samples were c-kit positive and 90% were CD34 positive. All three Thy-1 negative samples were CD34 positive, had a low proliferative index (Ki-67 ≤ 10%) and were located in the upper gastrointestinal tract (one in esophagus and two in the stomach). As a tendency, Thy-1 negative patients had a better prognosis, although not reaching level of significance due to low numbers. Conclusions Thy-1 is expressed in the majority of GISTs, suggesting a novel, additional standard marker for identifying GIST. Future studies should focus on the role of Thy-1 in the pathogenesis of GIST and subsequently on its potential to act as a molecular target for adjuvant therapy with new molecular antitumor agents. Financial support for this study was provided by research grants from the Hamburger Krebsgesellschaft e. V. (J.T.K., E.F.Y., J.R.I.).     

Oligodontia and associated characteristics: assessment in view of prosthodontic rehabilitation

Bibliographic evidence regarding oligodontia was reviewed to extract information necessary for a systematic review for a prosthodontic approach to management. Syndromic oligodontia, appearing as a symptom of many syndromes, was distinguished from isolated, or non-syndromic, which is an independent trait. Although a rare disorder, oligodontia has always been considerably researched, especially concerning its prevalence and genetic background. Non-syndromic oligodontia has been associated with the presence of small and misshapen natural teeth, orofacial clefting and reduced saliva secretion. A typical maxillofacial morphology has also been reported, which seems to result from the lack of dental and functional compensation and not from an altered growth pattern. Syndromic oligodontias also exhibit the above basic features but are complicated by each syndrome's specific characteristics. Prosthodontic treatment of individuals with oligodontia must anticipate the dental and oral clinical characteristics and provide with continuing support and preservation of proper maxillofacial relationships.     

Combinatorial stresses kill pathogenic Candida species

Pathogenic microbes exist in dynamic niches and have evolved robust adaptive responses to promote survival in their hosts. The major fungal pathogens of humans, Candida albicans and Candida glabrata, are exposed to a range of environmental stresses in their hosts including osmotic, oxidative and nitrosative stresses. Significant efforts have been devoted to the characterization of the adaptive responses to each of these stresses. In the wild, cells are frequently exposed simultaneously to combinations of these stresses and yet the effects of such combinatorial stresses have not been explored. We have developed a common experimental platform to facilitate the comparison of combinatorial stress responses in C. glabrata and C. albicans. This platform is based on the growth of cells in buffered rich medium at 30°C, and was used to define relatively low, medium and high doses of osmotic (NaCl), oxidative (H(2)O(2)) and nitrosative stresses (e.g., dipropylenetriamine (DPTA)-NONOate). The effects of combinatorial stresses were compared with the corresponding individual stresses under these growth conditions. We show for the first time that certain combinations of combinatorial stress are especially potent in terms of their ability to kill C. albicans and C. glabrata and/or inhibit their growth. This was the case for combinations of osmotic plus oxidative stress and for oxidative plus nitrosative stress. We predict that combinatorial stresses may be highly significant in host defences against these pathogenic yeasts.     

Internet use and misuse: a multivariate regression analysis of the predictive factors of internet use among Greek adolescents

The internet is an integral tool for information, communication, and entertainment among adolescents. As adolescents devote increasing amounts of time to utilizing the internet, the risk for adopting excessive and pathological internet use is inherent. The study objectives include assessing the characteristics and predictors of excessive internet use and evaluating the prevalence of pathological internet use among Greek adolescents. A cross-sectional study design was applied to this effect. The study population (n = 897) consisted of a random sample of adolescents residing in Athens, Greece. Self-completed questionnaires, pertaining to internet access characteristics and Young’s Internet Addiction Scale (YIAS) score, were applied in order to investigate the study objectives. The multivariate regression analysis indicated that the most significant predictors of overall internet use included accessing the internet via one’s own home portal and for the purpose of social interaction. Internet access via the school environment was a significant deterrent among low (1–3 h/week) internet users, while access via internet cafés was a significant predictor for high (11–20 h/week) internet users. Moreover, accessing the internet for the purposes of game playing was the most significant predictor for excessive (>20 h/week) internet use. The prevalence of borderline internet use among the study population was 12.8%, while 1.00% reported addictive internet use. Also, 10.4% of male excessive internet users reported addictive internet use (p < 0.0001). In conclusion, excessive internet use is predicted solely by the location of internet access (own home portal) and the scope of internet use (i.e., sites relating to socialization and game playing) and may lead to internet addiction, particularly among male adolescents.