164 research outputs found

    Bidimensional Tandem Mass Spectrometry for Selective Identification of Nitration Sites in Proteins.

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    Nitration of protein tyrosine residues is very often regarded as a molecular signal of peroxynitrite formation during development, oxidative stress, and aging. However, protein nitration might also have biological functions comparable to protein phosphorylation, mainly in redox signaling and in signal transduction. The major challenge in the proteomic analysis of nitroproteins is the need to discriminate modified proteins, usually occurring at substoichiometric levels from the large amount of nonmodified proteins. Moreover, precise localization of the nitration site is often required to fully describe the biological process. Existing methodologies essentially rely on immunochemical techniques either using 2D-PAGE fractionation in combination with western blot analyses or exploiting immunoaffinity procedures to selectively capture nitrated proteins. Here we report a totally new approach involving dansyl chloride labeling of the nitration sites that rely on the enormous potential of MSn analysis. The tryptic digest from the entire protein mixture is directly analyzed by MS on a linear ion trap mass spectrometer. Discrimination between nitro- and unmodified peptide is based on two selectivity criteria obtained by combining a precursor ion scan and an MS3 analysis. This new procedure was successfully applied to the identification of 3-nitrotyrosine residues in complex protein mixtures

    Real time detection of cache-based side-channel attacks using hardware performance counters

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    Cache-based side-channel attacks are increasingly exposing the weaknesses of many cryptographic libraries and tools by showing that, even though the algorithms might be considered strong, their implementations often lead to unexpected behaviors that can be exploited to obtain sensitive data, usually encryption keys. In this study we analyze three methods to detect cache-based side-channel attacks in real time, preventing or limiting the amount of leaked information. We focus our efforts on detecting three attacks on the well-known OpenSSL library: one that targets AES, one that targets RSA and one that targets ECDSA. The first method is based on monitoring the involved processes and assumes the victim process is known. By collecting and correlating the monitored data we find out whether there exists an attacker and pinpoint it. The second method uses anomaly detection techniques and assumes the benign processes and their behavior are known. By treating the attacker as a potential anomaly we understand whether an attack is in progress and which process is performing it. The last method is based on employing a neural network, a machine learning technique, to profile the attacker and to be able to recognize when a process that behaves suspiciously like the attacker is running. All the three of them can successfully detect an attack in about one fifth of the time required to complete it. We could not experience the presence of false positives in our test environment and the overhead caused by the detection systems is negligible. We also analyze how the detection systems behave with a modified version of one ofthe spy processes. With some optimization we are confident these systems can be used in real world scenarios

    HIV-1 Tropism Test Evaluation: Assessment and Clinical Implications

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    CCR5 and CXCR4 chemokines receptors are critical coreceptors for the binding of HIV to specific host cells. Guidelines recommend its assessment in case of virological failure or before prescription of CCR5 inhibitors. Strategies to assess viral tropism may be divided into phenotypic and genotypic assays; registrative trials of CCR5 inhibitors used phenotypic assay, but recently genotypic ones have been used in clinical practice. The presence of CXCR4 is increasing in naïve patients, with both acute and chronic HIV-1 infections; this coreceptor usage is associated with CD4 depletion. The assessment of viral tropism should be considered in every stage of HIV-1 infection

    High incidence of vascular complication after computed tomography guided lung biopsy : what's matter , the patient or the tecnique?

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    We read with interest the article of Anzidei on a predicitive score of complication after lung computed tomography -guided biopsy . We think there is a percentage of complications especially pneumotohorax which are impossible to avoid , but it would be useful to predict in which cases they occur with hiogh frequency

    Is Post-Operative Lung Ultrasonography Effective in Lung Abnormalities Analysis?

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    We read with interest the article of Dr. Patella (1) about the use of chest ultrasonography after thoracic surgery for pneumothorax evaluation and management. We completely agree about the use of ultrasound in the post-operative evaluation with the possibility to reduce the number of chest X-ray (CXR). In fact, it is well known that in many cases the postoperative CXR, especially when daily performed, represents a possible waste of time and resources(2)

    SICOB-endorsed national Delphi consensus on obesity treatment optimization: focus on diagnosis, pre-operative management, and weight regain/insufficient weight loss approach

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    Purpose: Overweight and obesity affects 60% of adults causing more than 1.2 million deaths across world every year. Fight against involved different specialist figures and multiple are the approved weapons. Aim of the present survey endorsed by the Italian Society of Bariatric Surgery (SICOB) is to reach a national consensus on obesity treatment optimization through a Delphi process. Methods: Eleven key opinion leaders (KOLs) identified 22 statements with a major need of clarification and debate. The explored pathways were: (1) Management of patient candidate to bariatric/metabolic surgery (BMS); (2) Management of patient not eligible for BMS; (3) Management of patient with short-term (2 years) weight regain (WR) or insufficient weight loss (IWL); (4) Management of the patient with medium-term (5 years) WR; and (5) Association between drugs and BMS as WR prevention. The questionnaire was distributed to 65 national experts via an online platform with anonymized results. Results: 54 out of 65 invited panelists (83%) respond. Positive consensus was reached for 18/22 statements (82%); while, negative consensus (s20.4; s21.5) and no consensus (s11.5, s17) were reached for 2 statements, respectively (9%). Conclusion: The Delphi results underline the importance of first-line interdisciplinary management, with large pre-treatment examination, and establish a common opinion on how to properly manage post-operative IWL/WR. Level of evidence v: Report of expert committees

    Does Myasthenia Gravis Affect Long-Term Survival in Thymic Carcinomas? An ESTS Database Analysis

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    Background: Thymic carcinoma is a rare and highly malignant tumor with a dismal prognosis, which occasionally coexists with myasthenia gravis (MG). This study aims to investigate the MG incidence on a surgical cohort of patients with thymic carcinoma and to explore its influence on long-term survival. Methods: the prospectively collected data from the ESTS database on thymic epithelial tumors were reviewed. Clinical, pathological, and survival information on thymic carcinoma were analyzed. Results: the analysis was conducted on 203 patients, with an equal gender distribution (96 males and 107 females). MG was detected in 22 (10.8%) patients, more frequently elderly (>60 years, p = 0.048) and male (p = 0.003). Induction therapy was performed in 22 (10.8%) cases. After surgery, 120 (59.1%) patients had a Masaoka stage II-III while complete resection (R0) was achieved in 158 (77.8%). Adjuvant therapy was performed in 68 cases. Mean follow-up was 60 (SD = 14) months. The 3-year, 5-year and 10-year survival rates were 79%, 75% and 63%, respectively. MG did not seem to influence long-term survival (5-year survival in non-MG-TCs 78% vs. 50% in MG-TCs, p = ns) as age < 60 years, female gender, early Masaoka stage, and postoperative radiotherapy did, conversely. Conclusions: myasthenia occurred in about 10% of thymic carcinomas and it did not seem to affect significantly the long-term prognosis in surgically treated thymic carcinoma-patients
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