PIN domain of Nob1p is required for D-site cleavage in 20S pre-rRNA

Nob1p (Yor056c) is essential for processing of the 20S pre-rRNA to the mature 18S rRNA. It is part of a pre-40S ribosomal particle that is transported to the cytoplasm and subsequently cleaved at the 3' end of mature 18S rRNA (D-site). Nob1p is also reported to participate in proteasome biogenesis, and it was therefore unclear whether its primary activity is in ribosome synthesis. In this work, we describe a homology model of the PIN domain of Nob1p, which structurally Mimics Mg2+-dependent exonucleases despite negligible similarity in primary sequence. Insights gained from this model were used to design a point mutation that was predicted to abolish the postulated enzymatic activity. Cells expressing Nob1p with this mutation failed to cleave the 20S pre-rRNA. This supports both the significance of the structural model and the idea that Nob1p is the long-sought D-site endonuclease.</p

Surgical treatment of solitary sternal metastasis from breast cancer Case report

Bone metastasis is a frequent and early complication of breast cancer. This case report describes a technique for a partial exeresis of the sternum and the reconstruction of the pleura with autologous dermis from the lower abdomen and the loss of substance with a myocutaneous flap

Thoracoscopy in pleural effusion –two techniques: awake single-access video-assisted thoracic surgery versus 2-ports video-assisted thoracic surgery under general anesthesia

Awake single access video-assisted thoracic surgery with local anesthesia improves procedure tolerance, reduces postoperative stay and costs. MATERIALS &amp; METHODS: Local anesthesia was made with lidocaine and ropivacaine. We realize one 20 mm incision for the 'single-access', and two incisions for the '2-trocars technique'. RESULTS: Mortality rate was 0% in both groups. Postoperative stay: 3dd ± 4 versus 4dd ± 5, mean operative time: 39 min versus 37 min (p &lt; 0.05). Chest tube duration: 2dd ± 5 versus 3dd ± 6. COMPLICATIONS: 11/95 versus 10/79. CONCLUSION: Awake technique reduce postoperative hospital stay and chest drainage duration, similar complications and recurrence rate. The authors can say that 'awake single-access VATS' is an optimal diagnostic and therapeutic tool for the management of pleural effusions, but above extends surgical indication to high-risk patients

Nodular histiocytic/mesothelial hyperplasia as consequence of chronic mesothelium irritation by sub-phrenic abscess.

Nodular histiocytic/mesothelial hyperplasia (NHMH) is a benign localized alteration, first described in 1975 by Rosai in the hernia sac [1]. Few pulmonary cases have been reported in literature [2–6]. Sometimes it has been reported in the pericardium [7,8] or presenting as an inguinal mass [9]. The ‘mesothelial/monocytic incidental cardiac excrescence’, first described by Weinot et al. in 1994 [10] is now considered a similar lesion to NHMH [11]. It consists of a reactive proliferation of histiocytes and mesothelium secondary to chronic irritation and it has been observed in pleura-damaging processes, such as pneumothorax [5], or as consequence of cardiac catheterization, inflammation, mechanical or tumor stimulation [11]. The rarity of NHMH and the moderate cytological atypia often present, make this lesion difficult to diagnose. It can be easily confused with primary mesothelial lesions and neoplasms such as adenocarcinomas, granulosa cell tumors or Langerhans’ histiocytosis. We report a case of pleural NHMH in a patient with a subphrenic abscess, in which no pulmonary pathogenic noxa was evident. We hypothesize a transdiaphragmatic chronic irritation as a pathogenetic mechanism underlying NHMH

Mediastinal syndrome from plasmablastic lymphoma in human immunodeficiency virus and human herpes virus 8 negative patient with polycythemia vera: a case report

Background: Plasmoblastic lymphoma is a rare and aggressive subtype of diffuse large B cell lymphoma, which occurs usually in the jaw of immunocompromised subjects. Case presentation: We describe the occurrence of plasmoblastic lymphoma in the mediastinum and chest wall skin of an human immunodeficiency virus-negative 63-year-old Caucasian man who had had polycytemia vera 7 years before. At admission, the patient showed a superior vena cava syndrome, with persistent dyspnoea, cough, and distension of the jugular veins. Imaging findings showed a 9.7 × 8 × 5.7 cm mediastinal mass. A chest wall neoformation biopsy and ultrasound-guided fine-needle aspiration biopsy of the mediastinal mass allowed diagnosis of plasmoblastic lymphoma and establishment of an immediate chemotherapeutic regimen, with rapid remission of compression symptoms. Conclusions: Plasmoblastic lymphoma is a very uncommon, difficult to diagnose, and aggressive disease. The presented case represents the first rare mediastinal plasmoblastic lymphoma in a human immunodeficiency virus-/human herpesvirus-8-negative patient. Pathologists should be aware that this tumor does appear in sites other than the oral cavity. Fine-needle aspiration biopsy is a low-cost, repeatable, easy-to-perform technique, with a high diagnostic accuracy and with very low complication and mortality rates. Fine-needle aspiration biopsy could represent the right alternative to surgery in those patients affected by plasmoblastic lymphoma, being rapid and minimally invasive. It allowed establishment of prompt medical treatment with subsequent considerable reduction of the neoplastic tissue and resolution of the mediastinal syndrome

Kinetic modelling of competition and depletion of shared miRNAs by competing endogenous RNAs

Non-conding RNAs play a key role in the post-transcriptional regulation of mRNA translation and turnover in eukaryotes. miRNAs, in particular, interact with their target RNAs through protein-mediated, sequence-specific binding, giving rise to extended and highly heterogeneous miRNA-RNA interaction networks. Within such networks, competition to bind miRNAs can generate an effective positive coupling between their targets. Competing endogenous RNAs (ceRNAs) can in turn regulate each other through miRNA-mediated crosstalk. Albeit potentially weak, ceRNA interactions can occur both dynamically, affecting e.g. the regulatory clock, and at stationarity, in which case ceRNA networks as a whole can be implicated in the composition of the cell's proteome. Many features of ceRNA interactions, including the conditions under which they become significant, can be unraveled by mathematical and in silico models. We review the understanding of the ceRNA effect obtained within such frameworks, focusing on the methods employed to quantify it, its role in the processing of gene expression noise, and how network topology can determine its reach.Comment: review article, 29 pages, 7 figure

Analisi dei fattori di rischio dell'ipoparatiroidismo transitorio e definitivo nei pazienti sottoposti a tiroidectomia

Obiettivi. Con questa revisione della letteratura ci proponiamo di valutare quali sono i fattori che possono essere valutati nei pazienti da sottoporre a tiroidectomia ai fini di una migliore gestione preoperatoria e post-operatoria dell\u2019ipoparatiroidismo transitorio e definitivo. Discussione. L\u2019ipoparatiroidismo transitorio \ue8 una complicanza potenzialmente grave che include una vasta gamma di segni e sintomi che permane solo per poche settimane dopo l\u2019intervento chirurgico. L\u2019ipoparatiroidismo definitivo si verifica quando \ue8 necessario un trattamento medico per un periodo maggiore di 12 mesi. I fattori di rischio che ne possono influenzare l\u2019insorgenza in seguito ad interventi di tiroidectomia sono molteplici: biochimici preoperatori e post opera- tori, il sesso femminile, la malattia di Graves e le malattie neoplastiche della tiroide, l\u2019abilit\ue0 del chirurgo e la tecnica chirurgica utilizzata. Il trattamento medico prevede la somministrazione di calcio, vitamina D e talvolta magnesio. Conclusioni: Anche se i fattori biologici e biochimici legati al paziente ricoprono una certa importanza nella correlazione con l\u2019ipoparatiroidismo, riteniamo che i fattori causali pi\uf9 importanti sono da correlare alle variabili intraoperatorie come l\u2019esperienza del chirurgo e la tecnica utilizzata che deve mirare alla visualizzazione e al rispetto in situ delle paratiroidi.Aims. This review evaluates those main risk factors that can affect patients undergoing thyroidectomy, to reach a better pre- and post-operative management of transient and permanent hypoparathyroidism. Discussion. The transient hypoparathyroidism is a potentially severe complication of thyroidectomy, including a wide range of signs and symptoms that persists for a few weeks. The definitive hypoparathyroidism occurs when a medical treatment is necessary over 12 months. Risk factors that may influence the onset of this condition after thyroidectomy include: pre- and post-operative biochemical factors, such as serum calcium levels, vitamin D blood concentrations and intact PTH. Other involved factors could be summarized as follow: female sex, Graves' or thyroid neoplastic diseases, surgeon's dexterity and surgical technique. The medical treatment includes the administration of calcium, vitamin D and magnesium sometimes. Conclusions. Although biological and biochemical factors could be related to iatrogenic hypoparathyroidism, the surgeon's experience and the used surgical technique still maintain a crucial role in the aetiology of this important complication

Dynamic Smagorinsky model on anisotropic grids

Large Eddy Simulation (LES) of complex-geometry flows often involves highly anisotropic meshes. To examine the performance of the dynamic Smagorinsky model in a controlled fashion on such grids, simulations of forced isotropic turbulence are performed using highly anisotropic discretizations. The resulting model coefficients are compared with a theoretical prediction (Scotti et al., 1993). Two extreme cases are considered: pancake-like grids, for which two directions are poorly resolved compared to the third, and pencil-like grids, where one direction is poorly resolved when compared to the other two. For pancake-like grids the dynamic model yields the results expected from the theory (increasing coefficient with increasing aspect ratio), whereas for pencil-like grids the dynamic model does not agree with the theoretical prediction (with detrimental effects only on smallest resolved scales). A possible explanation of the departure is attempted, and it is shown that the problem may be circumvented by using an isotropic test-filter at larger scales. Overall, all models considered give good large-scale results, confirming the general robustness of the dynamic and eddy-viscosity models. But in all cases, the predictions were poor for scales smaller than that of the worst resolved direction

Naf1p is a box H/ACA snoRNP assembly factor

Box H/ACA small nucleolar ribonucleoprotein particles (snoRNPs) contain four essential proteins, Cbf5p, Gar1p, Nhp2p, and Nop10p, each of which, with the exception of Gar1p, is required for box H/ACA snoRNA accumulation. Database searches identified a novel essential protein, which we termed Naf1p, with a region of homology to the RNA-binding domain of Gar1p and other features in common with hnRNP-like proteins. Naf1p is localized to the nucleus and is not a stable component of the H/ACA snoRNPs, but it is required for the accumulation of all box H/ACA snoRNAs. This requirement is not at the level of snoRNA transcription initiation or termination. Naf1p shows in vitro RNA-binding activity and also binds directly to Cbf5p and Nhp2p. Naf1p was shown to bind to the CTD in vivo in a two-hybrid assay, and the phosphorylated CTD, but not the nonphosphorylated CTD, was shown to precipitate tagged Naf1p from a cell lysate. We propose that Naf1p is recruited to the CTD of RNA polymerase 11 and binds to nascent box H/ACA snoRNAs promoting snoRNP assembly.</p

One shoot seldinger central venous catheterization in dialyzed patients

Introduction: Central Venous Catheterization is necessary in uremic patient (before dialysis) and many other conditions. In this study we demonstrated the advantages of ultrasonography to perform the procedure. Materials and methods: 48 uremic patient were submitted to ultrasound-guided central venous catheterization. The procedure was performed following the Seldinger “one shot” technique. Results: The mean operative time was 4 minutes, with a high rate of success (100%) and a low percentage of complications (2%). Conclusion: The ultrasound-guided central venous catheterization is a safe procedure, rapid and easy to perform. The procedure has a low rate of failures and complications and a high rate of success. It is suitable in all patients with vascular anatomical variations, “difficult neck”, or coagulation disorders