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Invertebrate predation on amphibians is widespread, although unreported in Europe. Here, we present documented predation of the Karpathos water frog (Pelophylax cerigensis) by the crab Potamon karpathos. Pelophylax cerigensis is an endangered, endemic species exclusively found on the Rhodes and Karpathos Islands in the South Aegean Sea, Greece. The Karpathos population is at risk due to limited suitable habitats and a scarcity of freshwater bodies on the island. From April to October, when there is no rain on the island, frogs and crabs cohabitate, sharing the same shallow ditches. Incidents of frog predation by crabs are common, indicated by numerous individuals with amputated limbs and scars, representing an additional threat to the endangered frog. Further research on the interactions between the two species is urgently required, as it has direct conservation implications.

Post-translational modifications of histones play a key role in DNA-based processes, like transcription, by modulating chromatin structure. N-terminal acetylation is unique among the numerous histone modifications because it is deposited on the N-alpha amino group of the first residue instead of the side-chain of amino acids. The function of this modification and its interplay with other internal histone marks has not been previously addressed. Here, we identified N-terminal acetylation of H4 (N-acH4) as a novel regulator of arginine methylation and chromatin silencing in Saccharomyces cerevisiae. Lack of the H4 N-alpha acetyltransferase (Nat4) activity results specifically in increased deposition of asymmetric dimethylation of histone H4 arginine 3 (H4R3me2a) and in enhanced ribosomal-DNA silencing. Consistent with this, H4 N-terminal acetylation impairs the activity of the Hmt1 methyltransferase towards H4R3 in vitro. Furthermore, combinatorial loss of N-acH4 with internal histone acetylation at lysines 5, 8 and 12 has a synergistic induction of H4R3me2a deposition and rDNA silencing that leads to a severe growth defect. This defect is completely rescued by mutating arginine 3 to lysine (H4R3K), suggesting that abnormal deposition of a single histone modification, H4R3me2a, can impact on cell growth. Notably, the cross-talk between N-acH4 and H4R3me2a, which regulates rDNA silencing, is induced under calorie restriction conditions. Collectively, these findings unveil a molecular and biological function for H4 N-terminal acetylation, identify its interplay with internal histone modifications, and provide general mechanistic implications for N-alpha-terminal acetylation, one of the most common protein modifications in eukaryotes.

A 67 year old man presented with non-invasive thymoma, associated aplastic anemia and important hypogammaglobulinemia; the postoperative course has been characterized, three months later, by thrombocytopenia (kept under control with steroid therapy) and, two years later, by squamous lung cancer, not susceptible of surgical treatment. The patient died five years after operation because of progression of the lung cancer. Anemia improved only partially after operation; there where no effects on hypogammaglobulinemia. Thymoma has been reported in literature in 50% of patients with aplastic anemia, 7-13% of adult patients with hypogammaglobulinemia is affected by thymoma, in 21% of patients that presented with thymoma other tumors have been discovered through clinical history.

Aim: To evaluate the clinical picture, diagnostic techniques and most appropriate treatment in traumatic diaphragmatic hernia with delayed presentation on the basis of personal experience and in the light of other published studies., Experimental Design: Review of cases treated., Setting: Patients treated in University General Surgery wards., Patients: Those patients in whom diagnosis was made some time after trauma and after the acute event were selected from a group of patients with traumatic diaphragmatic hernia., Surgery: All patients underwent surgery to reduce hernia and repair the diaphragmatic lesion., Measurements: All clinical findings were examined together with the tests performed and the type of treatment carried out., Results: The diagnosis was made between 3 months and 3 years after the injury. Three patients presented manifest symptoms of high intestinal occlusion on entry. Radiological alterations were present in standard chest X-rays in all patients and digestive tract contrast radiography was positive for the diagnosis of hernia in 3 out of 4 cases in which it was performed; a preoperative diagnosis of hernia was obtained in 4 cases. Patients were operated using a thoracotomy (3 cases) or combined laparothoracotomy access (2 cases); the diaphragmatic lesion, localised in all cases in the cupula of the left hemidiaphragm, was repaired using separate sutures in non-reabsorbable material without the use of grafts. One patient died postoperatively owing to septic complications., Conclusions: traumatic diaphragmatic hernia with delayed presentation involves severe complications that increase morbidity and operating mortality.

Aim: Retrospective evaluation of 19 diaphragmatic ruptures due to blunt trauma., Materials and Methods: We collected all patients with thoracic and/or abdominal blunt trauma who were admitted to the department of surgery (Clinica Chirurgica and Chirurgia generale C) from 1970 to 1995. We selected patients with ascertained diaphragmatic rupture., Results: We considered 17 cases of TDR (15 males and 4 females). Mean age was 38 years (range 16-67). Radiologic findings were consistent with TDR in 10 cases out of 17 (58.8%). Right hemidiaphragm was injured in 6 cases (31.6%). 10 patients (52.6%) presented at operation with intrathoracic visceral herniation. 8 patients underwent laparotomy, 7 both laparotomy and thoracotomy, 4 thoracotomy alone. Perioperative mortality was 15.7% (3 patients)., Discussion and Conclusions: The clinical features were complicated by a large number of associated lesions; radiologic diagnosis is comparatively easy if visceral herniation into the thorax is present, repeated radiologic examinations facilitate diagnosis. The surgical access is determined by concomitant associated injuries which may require urgent operation.