125 research outputs found

    A rapid spectroscopic method to detect the fraudulent treatment of tuna fish with carbon monoxide

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    Carbon monoxide (CO) can be used to treat fresh meat and fish in order to retain its 'fresh' red colour appearance for a longer period of time. In fact, upon aging, myoglobin is oxidized to met-myoglobin with the concomitant blue-shift and broadening of the Soret maximum, which brings about a change in the colour of the fish, revealing that it is no longer fresh. The use of carbon monoxide, which reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish has been investigated by optical spectroscopy as the formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. The presence of met- and oxy-myoglobin can obscure the presence of small amounts of the CO adduct; however, it can be revealed by chemically reducing the met- and oxy-forms to the deoxy-form in an anaerobic environment. This spectroscopic method provides a qualitatively rapid laboratory screening procedure for food control to unmask the presence of CO in frozen or fresh fish. (c) 2006 Elsevier Ltd. All rights reserved

    Role of lysines in cytochrome c – cardiolipin interaction

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    Cytochrome c undergoes structural variations during the apoptotic process; such changes have been related with modifications occurring in the protein when it forms a complex with cardiolipin, one of the phospholipids constituting the mitochondrial membrane. Although several studies have been performed to identify the site(s) of the protein involved in the cytochrome c/cardiolipin interaction, to date the location of this hosting region(s) remains unidentified and is a matter of debate. To gain a deeper insight into the reaction mechanism, we investigate the role that the Lys72, Lys73 and Lys79 residues play in the cytochrome c/cardiolipin interaction, as these side chains appear to be critical for cytochrome c/cardiolipin recognition. The Lys72Asn, Lys73Asn, Lys79Asn, Lys72/73Asn and Lys72/73/79Asn mutants of horse heart cytochrome c were produced and characterized by circular dichroism, UV-visible and resonance Raman spectroscopies, and the effects of the mutations on the interaction of the variants with cardiolipin have been investigated. The mutants are characterized by a subpopulation with non-native axial coordination, and are less stable than the wild type protein. Furthermore, the mutants lacking Lys72 and/or Lys79 do not bind cardiolipin and those lacking Lys73, although they form a complex with the phospholipid, do not show any peroxidase activity. These observations indicate that the Lys72, Lys73 and Lys79 residues stabilize the native axial Met80-Fe(III) coordination as well as the tertiary structure of cytochrome c. Moreover, while Lys72 and Lys79 are critical for cytochrome c/cardiolipin recognition, the simultaneous presence of Lys72, Lys73 and Lys79 is necessary for peroxidase activity of cardiolipin-bound cytochrome c

    Multiparametric magnetic resonance imaging for the differential diagnosis between granulomatous prostatitis and prostate cancer: a literature review to an intriguing diagnostic challenge

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    Multiparametric magnetic resonance imaging (mpMRI) is currently the most effective diagnostic tool for detecting prostate cancer (PCa) and evaluating adenocarcinoma-mimicking lesions of the prostate gland, among which granulomatous prostatitis (GP) represents the most interesting diagnostic challenge. GP consists of a heterogeneous group of chronic inflammatory lesions that can be differentiated into four types: idiopathic, infective, iatrogenic, and associated with systemic granulomatous disease. The incidence of GP is growing due to the increase in endourological surgical interventions and the adoption of intravesical instillation of Bacillus Calmette-Guerin in patients with non-muscle invasive bladder cancer; therefore, the difficulty lies in identifying specific features of GP on mpMRI to avoid the use of transrectal prostate biopsy as much as possible

    Transverse prostate maximum sectional area can predict clinically significant prostate cancer in PI-RADS 3 lesions at multiparametric magnetic resonance imaging

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    BackgroundTo evaluate multiparametric magnetic resonance imaging (mpMRI) parameters, such as TransPA (transverse prostate maximum sectional area), TransCGA (transverse central gland sectional area), TransPZA (transverse peripheral zone sectional area), and TransPAI (TransPZA/TransCGA ratio) in predicting prostate cancer (PCa) in prostate imaging reporting and data system (PI-RADS) 3 lesions. MethodsSensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), the area under the receiver operating characteristic curve (AUC), and the best cut-off, were calculated. Univariate and multivariate analyses were carried out to evaluate the capability to predict PCa. ResultsOut of 120 PI-RADS 3 lesions, 54 (45.0%) were PCa with 34 (28.3%) csPCas. Median TransPA, TransCGA, TransPZA and TransPAI were 15.4cm(2), 9.1cm(2), 5.5cm(2) and 0.57, respectively. At multivariate analysis, location in the transition zone (OR=7.92, 95% CI: 2.70-23.29, P<0.001) and TransPA (OR=0.83, 95% CI: 0.76-0.92, P<0.001) were independent predictors of PCa. The TransPA (OR=0.90, 95% CI: 0.082-0.99, P=0.022) was an independent predictor of csPCa. The best cut-off of TransPA for csPCa was 18 (Sensitivity 88.2%, Specificity 37.2%, PPV 35.7%, NPV 88.9%). The discrimination (AUC) of the multivariate model was 0.627 (95% CI: 0.519-0.734, P<0.031). ConclusionsIn PI-RADS 3 lesions, the TransPA could be useful in selecting patients requiring biopsy

    PSMA-PET Guided Treatment in Prostate Cancer Patients with Oligorecurrent Progression after Previous Salvage Treatment

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    Background: Prostate Specific Membrane Antigen-Positron Emission Tomography (PSMA-PET) is used to select recurrent prostate cancer (PCa) patients for metastases-directed therapy (MDT). We aimed to evaluate the oncologic outcomes of second-line PSMA-guided MDT in oligo-recurrent PCa patients. Methods: we performed a retrospective analysis of 113 recurrent PCa after previous radical prostatectomy and salvage therapies with oligorecurrent disease at PSMA-PET (≤3 lesions in N1/M1a-b) in three high-volume European centres. Patients underwent second-line salvage treatments: MDT targeted to PSMA (including surgery and/or radiotherapy), and the conventional approach (observation or Androgen Deprivation Therapy [ADT]). Patients were stratified according to treatments (MDT vs. conventional approach). Patients who underwent MDT were stratified according to stage in PSMA-PET (N1 vs. M1a-b). The primary outcome of the study was Progression-free survival (PFS). Secondary outcomes were Metastases-free survival (MFS) and Castration Resistant PCa free survival (CRPC-FS). Kaplan-Meier analyses assessed PFS, MFS and CRPC-FS. Multivariable Cox regression models identified predictors of progression and metastatic disease. Results: Overall, 91 (80%) and 22 (20%) patients were treated with MDT and the conventional approach, respectively. The median follow-up after PSMA-PET was 31 months. Patients who underwent MDT had a similar PFS compared to the conventional approach (p = 0.3). Individuals referred to MDT had significantly higher MFS and CRPC-FS compared to those who were treated with the conventional approach (73.5% and 94.7% vs. 30.5% and 79.5%; all p ≤ 0.001). In patients undergoing MDT, no significant differences were found for PFS and MFS according to N1 vs. M1a-b disease, while CRPC-FS estimates were significantly higher in patients with N1 vs. M1a-b (100% vs. 86.1%; p = 0.02). At multivariable analyses, age (HR = 0.96) and ADT during second line salvage treatment (HR = 0.5) were independent predictors of PFS; MDT (HR 0.27) was the only independent predictor of MFS (all p ≤ 0.04) Conclusion: Patients who underwent second-line PSMA-guided MDT experienced higher MFS and CRPC-FS compared to men who received conventional management

    Coronary stenting and surgery: Perioperative management of antiplatelet therapy in patients undergoing surgery after coronary stent implantation [Stent coronarico e chirurgia: La gestione perioperatoria della terapia antiaggregante nel paziente portatore di stent coronarico candidato a intervento chirurgico]

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    The management of antiplatelet therapy in patients with coronary stents undergoing surgery is a growing clinical problem and often represents a matter of debate between cardiologists and surgeons. It has been estimated that about 4-8% of patients undergoing coronary stenting need to undergo surgery within the next year. Surgery represents one of the most common reasons for premature antiplatelet therapy discontinuation, which is associated with a significant increase in mortality and major adverse cardiac events, in particular stent thrombosis. In addition, surgery confers an additional risk of perioperative cardiac ischemic events, being high in these patients because of the pro-inflammatory and pro-thrombotic effects of surgery. Current international guidelines recommend to postpone non-urgent surgery for at least 6 weeks after bare metal stent implantation and for 6-12 months after drug-eluting stent implantation. However, these recommendations provide little support with regard to managing antiplatelet therapy in the perioperative phase in case of urgent operations and/or high hemorrhagic risk. Furthermore, ischemic and hemorrhagic risk is not defined in detail on the basis of clinical and procedural characteristics. Finally, guidelines shared with cardiologists and surgeons are lacking. The present consensus document provides practical recommendations on the management of antiplatelet therapy in the perioperative period in patients with coronary stents undergoing surgery. Cardiologists and surgeons contributed equally to its creation. An ischemic risk stratification has been provided on the basis of clinical and procedural data. All surgical interventions have been defined on the basis of the hemorrhagic risk. A consensus on the most appropriate antiplatelet regimen in the perioperative phase has been reached on the basis of the ischemic and hemorrhagic risk. Dual antiplatelet therapy should not be withdrawn for surgery at low bleeding risk, whereas aspirin should be continued perioperatively in the majority of surgical operations. In the event of interventions at high risk for both bleeding and ischemic events, when oral antiplatelet therapy withdrawal is required, perioperative treatment with short-acting intravenous glycoprotein IIb/IIIa inhibitors (tirofiban or eptifibatide) should be considered. \ua9 2012 Il Pensiero Scientifico Editore
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