University of Graz

About: University of Graz is a education organization based out in Graz, Steiermark, Austria. It is known for research contribution in the topics: Population & Quantum chromodynamics. The organization has 17934 authors who have published 37489 publications receiving 1110980 citations. The organization is also known as: Carolo Franciscea Graecensis & Karl Franzens Universität.

Maternal methylation imprints on human chromosome 15 are established during or after fertilization

Abstract: Prader-Willi syndrome (PWS) is a neurogenetic disorder that results from the lack of transcripts expressed from the paternal copy of the imprinted chromosomal region 15q11-q13 (refs. 1,2). In some patients, this is associated with a deletion of the SNURF-SNRPN exon 1 region inherited from the paternal grandmother and the presence of a maternal imprint on the paternal chromosome. Assuming that imprints are reset in the germ line, we and others have suggested that this region constitutes part of the 15q imprinting center (IC) and is important for the maternal to paternal imprint switch in the male germ line. Here we report that sperm DNA from two males with an IC deletion had a normal paternal methylation pattern along 15q11-q13. Similar findings were made in a mouse model. Our results indicate that the incorrect maternal methylation imprint in IC deletion patients is established de novo after fertilization. Moreover, we found that CpG-rich regions in SNURF-SNRPN and NDN, which in somatic tissues are methylated on the maternal allele, are hypomethylated in unfertilized human oocytes. Our results indicate that the normal maternal methylation imprints in 15q11-q13 also are established during or after fertilization.

Dermatoscopy of facial actinic keratosis, intraepidermal carcinoma, and invasive squamous cell carcinoma: A progression model

Abstract: Background Little is known about the dermoscopic features of keratinocyte skin cancer. Objective We sought to determine the dermoscopic features of facial actinic keratosis (AK), intraepidermal carcinoma (IEC), moderately to poorly differentiated invasive squamous cell carcinoma (SCC), and well-differentiated SCC of the keratoacanthoma type. Methods This was a retrospective analysis of dermoscopic images of histopathologically diagnosed keratinocyte skin cancer. Results A total of 243 (70 AK, 71 IEC, 78 SCC, and 24 keratoacanthomas) tumors of the face from 243 patients (mean age: 71.1 years; range: 44-94 years) were analyzed. The majority of patients had a fair skin type, history of melanoma or nonmelanoma skin cancer, and multiple AK. A red pseudonetwork was significantly associated with AK ( P P P Limitations The retrospective design of our study and the lack of assessment of sensitivity and specificity of the dermoscopic criteria are limitations. Conclusions Based on our findings we propose a progression model of facial AK developing into IEC and invasive SCC.