18 research outputs found
Malignant solitary fibrous tumor involving the liver
Solitary fibrous tumors are predominantly benign and are most commonly found in the thoracic cavity and pleura; while reports exist in the literature of malignant solitary fibrous tumors and those located in extrathoracic organs, these cases are considered extremely rare. Herein, a case is reported of a malignant solitary fibrous tumor involving the liver that was diagnosed and treated in a 62-year-old woman. The patient presented with complaints of upper abdominal pain and unintentional weight loss. Computed tomography scan of the abdomen revealed a remarkably large mass, measuring 15 cm Ă— 10 cm Ă— 20 cm, which appeared to be unrelated to any particular organ. The intraoperative finding of a wide communication with the left liver suggested hepatic origin, and served as an indicator for tumor resection via left hemihepatectomy. The diagnosis of solitary fibrous tumor and its malignant nature was confirmed by histological and immunohistochemical examination of the resected tissues. Hepatic solitary fibrous tumor is very rare, and surgery remains the mainstay of treatment. Due to limited reports of such tumors in the literature, little can be said about the benefit of adjuvant therapy and prognosis for the rare cases with malignant histological findings
Regulation of Translesion Synthesis DNA Polymerase η by Monoubiquitination
DNA polymerase eta is a Y family polymerase involved in translesion synthesis (TLS). Its action is initiated by simultaneous interaction between the PIP box in pol eta and PCNA and between the UBZ in pol eta and monoubiquitin attached to PCNA. Whereas monoubiquitination of PCNA is required for its interaction with pol eta during TLS, we now show that monoubiquitination of pol eta inhibits this interaction, preventing its functions in undamaged cells. Identification of monoubiquitination sites within pol eta nuclear localization signal (NLS) led to the discovery that pol eta NLS directly contacts PCNA, forming an extended pol eta-PCNA interaction surface. We name this the PCNA-interacting region (PIR) and show that its monoubiquitination is downregulated by various DNA-damaging agents. We propose that this mechanism ensures optimal availability of nonubiquitinated, TLS-competent pol eta after DNA damage. Our work shows how monoubiquitination can either positively or negatively regulate the assembly of a protein complex, depending on which substrates are targeted by ubiquitin
Functional characterization of Rad18 domains for Rad6, ubiquitin, DNA binding and PCNA modification
Rad18 is a ubiquitin E3 ligase that monoubiquitinates PCNA on stalled replications forks. This allows recruitment of damage-tolerant polymerases for damage bypass and DNA repair. In this activity, the Rad18 protein has to interact with Rad6, the E2 ubiquitin-conjugating enzyme, ubiquitin, PCNA and DNA. Here we analyze the biochemical interactions of specific domains of the Rad18 protein. We found that the Rad6/Rad18 complex forms stable dimers in vitro. Consistent with previous findings, both the Ring domain and a C-terminal region contribute to the Rad6 interaction, while the C-terminus is not required for the interaction with PCNA. Surprisingly we find that the C2HC zinc finger is important for interaction with ubiquitin, apparently analogous to the interactions of classical zinc fingers with ubiquitin such as found in the UBZ and UBM domains in Y-family polymerases. Finally we find that the SAP domain, but not the zinc finger domain, is capable of DNA binding in vitro
Management of intra-thoracic anastomotic leakages after esophagectomy: updated systematic review and meta-analysis of endoscopic vacuum therapy versus stenting
Despite a significant decrease of surgery-related mortality and morbidity, anastomotic leakage still occurs in a significant number of patients after esophagectomy. The two main endoscopic treatments in case of anastomotic leakage are self-expanding metal stents (SEMS) and the endoscopic vacuum therapy (EVT). It is still under debate, if one method is superior to the other. Therefore, we performed a systematic review and meta-analysis of the existing literature to compare the effectiveness and the related morbidity of SEMS and EVT in the treatment of esophageal leakage. We systematically searched for studies comparing SEMS and EVT to treat anastomotic leak after esophageal surgery. Predefined endpoints including outcome, treatment success, endoscopy, treatment duration, re-operation rate, intensive care and hospitalization time, stricture rate, morbidity and mortality were assessed and included in the meta-analysis. Seven retrospective studies including 338 patients matched the inclusion criteria. Compared to stenting, EVT was significantly associated with higher healing (OR 2.47, 95% CI [1.30 to 4.73]), higher number of endoscopic changes (pooled median difference of 3.57 (95% CI [2.24 to 4.90]), shorter duration of treatment (pooled median difference - 11.57 days; 95% CI [- 17.45 to - 5.69]), and stricture rate (OR 0.22, 95% CI [0.08 to 0.62]). Hospitalization and intensive care unit duration, in-hospital mortality rate, rate of major and treatment related complications, of surgical revisions and of esophago-tracheal fistula failed to show significant differences between the two groups. Our analysis indicates a high potential for EVT, but because of the retrospective design of the included studies with potential biases, these results must be interpreted with caution. More robust prospective randomized trials should further investigate the potential of the two procedures
Molecular Profile of Gastrointestinal Stromal Tumors in Sixty-Eight Patients from a Single Swiss Institution.
Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. It has distinct molecular features and primarily affects the KIT and PDGFRA genes
Knowledge and Influence of Predatory Journals in Dermatology: A Pan-Austrian Survey
The aim of this study was to assess the knowledge and influence of predatory journals in the field of dermatology in Austria. A total of 286 physicians (50.5% men) completed a questionnaire. The vast majority of subjects read scientific articles (n = 281, 98.3%) and took them into consideration in their clinical decision-making (n = 271, 98.5% of participants that regularly read scientific literature). Open access was known by 161 (56.3%), predatory journals by 84 (29.4%), and the Beall’s list by 19 physicians (6.7%). A total of 117 participants (40.9%) had been challenged by patients with results from the scientific literature, including 9 predatory papers. Participants who knew of predatory journals had a higher level of education as well as scientific experience, and were more familiar with the open-access system (p <0.001). These results indicate that the majority of dermatologists are not familiar with predatory journals. This is particularly the case for physicians in training and in the early stages of their career