81 research outputs found
Sutureless technique to support anastomosis during thoracic aorta replacement
<p>Abstract</p> <p>Background</p> <p>In aortic replacement procedures the aortic wall and Teflon strips form a double layer, with the use of continuous sutures. Surgical glues may or may not be used to enhance the durability of the anastomoses. In this technical report a modification of the aortic stumps preparation is devised.</p> <p>The technique reduces substantially the preparation time of the aortic stumps by the use of ligation clips and a surgical sealant.</p> <p>Technique</p> <p>Suturing is the standard method for the aortic-teflon double-layer formation prior to Dacron anastomosis. In this study, instead of suturing, 5-6 ligation clips are primarily applied on the exterior of the double layer to facilitate proper cooptation. Secondarily, in order to fuse the two layers together, a sealant is injected in between the Teflon and aortic wall. Thus each stump is delivered quickly sutureless for the Dacron anastomosis.</p> <p>Between January 2003 and March 2009 this modified operative technique was performed in 14 cases (group A) with a mean age of 50 ± 16 years. This was contrasted against 24 controls (group B), with a mean age of 40 ± 28 years, treated with the conventional method, where only continuous sutures were used during the anastomosis. All patients were cases of ascending aorta replacement and/or aortic hemi-arch replacement, for acute aortic dissection or aortic dilatation.</p> <p>Results</p> <p>The pure anastomosis time (stump preparation and Dacron connection) was shortened by approximately 25 minutes depending on surgeon's experience. The anastomosis blood-loss was also significantly reduced in the sutureless group A, as evident by the dry operative field and the limited use of blood products, post-prosthetic graft anastomosis. This reflected to a faster post-operative recovery, faster extubation and fewer complications. At a mean follow-up of 21 ± 7 days, there were no post-operative deaths being related to acute aortic dissection or rupture of the anastomotic site.</p> <p>Conclusion</p> <p>Aortic replacement with the combination of ligation clips and a surgical sealant vs. sutures alone allows easy manipulations of the aorta and adaptation of the diameters, thus optimizing aortic operational timings and hemostasis. Moreover, it prevents blood loss and aortic wall trauma from multiple sutures.</p
Encrypted and Covert DNS Queries for Botnets: Challenges and Countermeasures
There is a continuous increase in the sophistication that modern malware
exercise in order to bypass the deployed security mechanisms. A typical
approach to evade the identification and potential take down of a botnet
command and control server is domain fluxing through the use of Domain
Generation Algorithms (DGAs). These algorithms produce a vast amount of
domain names that the infected device tries to communicate with to find the
C&C server, yet only a small fragment of them is actually registered. This
allows the botmaster to pivot the control and make the work of seizing the
botnet control rather difficult.
Current state of the art and practice considers that the DNS queries performed by a compromised device are transparent to the network administrator and therefore can be monitored, analysed, and blocked. In this work, we
showcase that the latter is a strong assumption as malware could efficiently
hide its DNS queries using covert and/or encrypted channels bypassing the
detection mechanisms. To this end, we discuss possible mitigation measures
based on traffic analysis to address the new challenges that arise from this
approach
Multi-center study of inter-rater reproducibility, image quality, and diagnostic accuracy of CZT versus conventional SPECT myocardial perfusion imaging
Cadmium-zinc-telluride (CZT)-based detectors exhibit higher diagnostic sensitivity in myocardial perfusion imaging (MPI) than conventional Anger-MPI for detection of coronary artery disease (CAD); however, reduced specificity and diagnostic accuracy of CZT-MPI were observed. This study aims to compare these different camera systems and to examine the degree of inter-rater reproducibility among readers with varying experience in MPI. 83 patients who underwent double stress/rest examinations using both a CZT and conventional SPECT cameras within one visit were included. Anonymized and randomized MPI-images were distributed to 15 international readers using a standardized questionnaire. Subsequent coronary angiography findings of ten patients served as a reference for analysis of sensitivity and specificity. Image quality was significantly better in CZT-MPI with significantly lower breast attenuation (P < 0.05). CZT-MPI exhibited higher sensitivity than Anger-MPI (87.5% vs. 62.5%) and significantly reduced specificity (40% vs. 100%). Readers experienced with both camera systems had the highest inter-rater agreement indicating higher reproducibility (CZT 0.54 vs. conv. 0.49, P < 0.05). Higher diagnostic sensitivity of CZT-MPI offers advantages in detection of CAD yet potentially of at the cost of reduced specificity, therefore it requires special training and a differentiated evaluation approach, especially for non-experienced readers with such camera systems. The online version contains supplementary material available at 10.1007/s12350-022-03054-w
No improvement in long-term survival over time for chronic lymphocytic leukemia patients in stereotyped subsets #1 and #2 treated with chemo(Immuno)therapy
Multicentre multi-device hybrid imaging study of coronary artery disease: results from the EValuation of INtegrated Cardiac Imaging for the Detection and Characterization of Ischaemic Heart Disease (EVINCI) hybrid imaging population
AIMS:
Hybrid imaging provides a non-invasive assessment of coronary anatomy and myocardial perfusion. We sought to evaluate the added clinical value of hybrid imaging in a multi-centre multi-vendor setting.
METHODS AND RESULTS:
Fourteen centres enrolled 252 patients with stable angina and intermediate (20-90%) pre-test likelihood of coronary artery disease (CAD) who underwent myocardial perfusion scintigraphy (MPS), CT coronary angiography (CTCA), and quantitative coronary angiography (QCA) with fractional flow reserve (FFR). Hybrid MPS/CTCA images were obtained by 3D image fusion. Blinded core-lab analyses were performed for CTCA, MPS, QCA and hybrid datasets. Hemodynamically significant CAD was ruled-in non-invasively in the presence of a matched finding (myocardial perfusion defect co-localized with stenosed coronary artery) and ruled-out with normal findings (both CTCA and MPS normal). Overall prevalence of significant CAD on QCA (>70% stenosis or 30-70% with FFR 640.80) was 37%. Of 1004 pathological myocardial segments on MPS, 246 (25%) were reclassified from their standard coronary distribution to another territory by hybrid imaging. In this respect, in 45/252 (18%) patients, hybrid imaging reassigned an entire perfusion defect to another coronary territory, changing the final diagnosis in 42% of the cases. Hybrid imaging allowed non-invasive CAD rule-out in 41%, and rule-in in 24% of patients, with a negative and positive predictive value of 88% and 87%, respectively.
CONCLUSION:
In patients at intermediate risk of CAD, hybrid imaging allows non-invasive co-localization of myocardial perfusion defects and subtending coronary arteries, impacting clinical decision-making in almost one every five subjects
A Novel, Cell-Free Therapy to Enter Our Hearts: The Potential Role of Small EVs in Prevention and Treatment of CVD
Heart disease constitutes one of the leading causes of morbidity and mortality worldwide. Current therapeutic techniques, such as interventional revascularization, although lifesaving, come along with myocardial injury related to the reperfusion itself, called ischemia-reperfusion injury, which is an added factor for increased morbidity. For that reason, there is an imperative need for novel therapies to be developed that would either prevent or treat myocardial injury. Extracellular vesicles (EVs), specifically small EVs (sEVs), have proven to be important mediators of intercellular communication. The fact that they carry information reflecting that of the parental cell makes them an ideal candidate for diagnostic purposes. sEVs derived from immunoregulatory cells, such as mesenchymal stem cells or cardiac progenitor cells, could also be used therapeutically to exert the primary immunomodulatory function but without carrying the side effects related to cell therapy. Furthermore, as a natural product, they have the added advantage of low immunogenicity, offering the potential for safe drug delivery. In the field of cardiology, there has been great interest in the therapeutic and diagnostic potential of sEVs with significant translational potential. Here, we review the potential use of sEVs in the context of myocardial ischemia and ischemia-reperfusion injury
THE ROLE OF TC - 99MΜ - MIBI IN THE ASSESSMENT OF MYOCARDIAL PERFUSION FUNCTION AND VIABILITY
ΜΕΛΕΤΗ: ΕΚΤΙΜΗΣΑΜΕ ΤΗΝ ΠΕΡΙΟΧΙΚΗ ΜΥΟΚΑΡΔΙΑΚΗ ΛΕΙΤΟΥΡΓΙΑ ΣΥΓΚΡΙΝΟΝΤΑΣ ΤΗΝ GATEDTC - 99M - MIBI ΤΟΜΟΓΡΑΦΙΑ ΕΚΠΟΜΠΗΣ ΜΕ ΤΟ MRI (ΠΡΩΤΟΚΟΛΛΟ 1) ΚΑΙ ΕΞΕΤΑΣΑΜΕ ΤΟ ΡΟΛΟ ΤΟΥ TC - 99M - MIBI ΣΤΗΝ ΕΚΤΙΜΗΣΗ ΤΗΣ ΜΥΟΚΑΡΔΙAΚΗΣ ΒΙΩΣΙΜΟΤΗΤΟΣ (ΠΡΩΤΟΚΟΛΛΟ 2). ΕΠΙΣΗΣ, ΕΞΕΤΑΣΘΗΚΕ Η ΠΙΘΑΝΟΤΗΤΑ ΕΦΑΡΜΟΓΗΣ ΕΝΟΣ ΤΑΧΕΟΣ ΠΡΩΤΟΚΟΛΛΟΥ ΣΥΝΔΥΑΖΟΝΤΑΣ ΘΑΛΛΙΟ - 201 ΚΑΙ TC - 99M - MIBI. ΜΕΘΟΔΟΙ ΚΑΙ ΑΠΟΤΕΛΕΣΜΑΤΑ: GATED ΤΟΜΟΓΡΑΦΙΑ ΕΚΠΟΜΠΗΣ ΜΕ TC - 99M - MIBI ΚΑΙ CINE - MRI ΠΡΑΓΜΑΤΟΠΟΙΗΘΗΚΑΝ ΕΝ ΗΡΕΜΙΑ ΣΕ 24 (9 ΜΕ ΠΡΟΗΓΟΥΜΕΝΟ ΕΜΦΡΑΓΜΑ) ΑΣΘΕΝΕΙΣ. ΣΤΟ ΔΕΥΤΕΡΟ ΠΡΩΤΟΚΟΛΛΟ ΜΕΛΕΤΗΣΑΜΕ 30 (16 ΜΕ ΦΥΣΙΟΛΟΓΙΚΗ ΚΑΙ 14 ΜΕ ΕΠΗΡΕΑΣΜΕΝΗ ΚΟΙΛΙΑΚΗ ΛΕΙΤΟΥΡΓΙΑ) ΑΣΘΕΝΕΙΣ. ΑΝΑΛΥΣΑΜΕ ΚΑΙ ΣΥΓΚΡΙΝΑΜΕ ΤΙΣ ΤΟΜΟΓΡΑΦΙΚΕΣ ΕΙΚΟΝΕΣ ΤΟΥ TC - 99M - MIBI (UNGATED ΚΑΙ GATED) ΜΕ ΑΥΤΕΣ ΤΗΣ ΑΝΑΚΑΤΑΝΟΜΗΣ ΚΑΙ ΗΡΕΜΙΑΣ ΤΟΥ ΘΑΛΛΙΟΥ - 201. ΠΡΩΤΟΚΟΛΛΟ1: ΣΤΟΥΣ ΑΣΘΕΝΕΙΣ ΜΕ ΦΥΣΙΟΛΟΓΙΚΗ ΜΥΟΚΑΡΔΙΑΚΗ ΑΙΜΑΤΩΣΗ, Η ΣΥΣΤΑΛΤΙΚΟΤΗΤΑ ΕΚΤΙΜΗΘΗΚΕ ΩΣ ΦΥΣΙΟΛΟΓΙΚΗ ΑΠΟ ΤΗ GATED ΤΟΜΟΓΡΑΦΙΑ ΚΑΙ ΤΟ MRI, ΕΝΩ ΣΕ ΑΣΘΕΝΕΙΣ ΜΕ ΠΡΟΗΓΟΥΜΕΝΟ ΕΜΦΡΑΓΜΑ ΤΟΥ ΜΥΟΚΑΡΔΙΟΥ ΚΑΙ ΟΙ ΔΥΟ ΤΕΧΝΙΚΕΣ ΕΔΕΙΞΑΝ ΑΝΩΜΑΛΙΕΣ ΣΥΣΤΑΛΤΙΚΟΤΗΤΑΣ. Η ΣΥΜΦΩΝΙΑ ΜΕΤΑΞΥ ΤΩΝ ΔΥΟ ΤΕΧΝΙΚΩΝ ΣΤΟ ΣΥΝΟΛΟ ΤΩΝ ΕΞΕΤΑΣΘΕΝΤΩΝ ΤΜΗΜΑΤΩΝ ΗΤΑΝ ΚΑΛΗ ΓΙΑ ΤΗΝ ΤΟΙΧΩΜΑΤΙΚΗ ΚΙΝΗΤΙΚΟΤΗΤΑ (Κ=0.66) ΚΑΙ ΤΗΝ ΣΥΣΤΟΛΙΚΗ ΠΑΧΥΝΣΗ (Κ=0.69) ΕΝΩ ΣΕ ΤΜΗΜΑΤΑ ΜΕ ΠΡΟΣΛΗΨΗ 0.05). (ΠΕΡΙΚΟΠΗ ΠΕΡΙΛΗΨΗΣ)WE HAVE VALIDATED ECG - GATED EMISSION TOMOGRAPHY USING ^99MTC - MIBI FOR THE ASSESSMENT OF REGIONAL VENTRICULAR FUNCTION BY COMPARING IT WITH CINE - MRI (PROTOCOL 1). WE HAVE ALSO COMPARED REST ^99MTC - MIBI TOMOGRAMS WITH STRESS - REDISTRIBUTION AND DELAYED REST^ 201TI IMAGES (PROTOCOL 2) IN ORDER TO COMPARE THE TRACERS FOR THE ASSESSMENT OF MYOCARDIAL VIABILITY AND TO VALIDATE A RAPIDPROTOCOL COMBINING THE TWO TRACERS. METHODS AND RESULTS: GATED TOMOGRAPHY ANDCINE MRI WAS PERFORMED AT REST IN 24 PATIENTS, 9 WITH PREVIOUS MYOCARDIAL INFARCTION. FOR THE SECOND PROTOCOL WE STUDIED 30 CONSECUTIVE PATIENTS DIVIDED INTO TWO GROUPS: 16 WITH NORMAL LEFT VENTRICULAR FUNCTION AND 14 WITH ABNORMAL FUNCTION. WE HAVE COMPARED: REST (UNGATED AND GATED) ^99MTC - MIBI IMAGES WITH REDISTRIBUTION ^201TI AND REST ^201TI IMAGES. PROTOCOL 1: IN 8 PATIENTS WITHOUT CAD, WALL MOTION AND THICKENING WERE NORMAL BY BOTH GATED TOMOGRAPHY AND MRI. GATED TOMOGRAPHY SHOWED ABNORMAL WALL MOTION OR THICKENING IN ALL PATIENTS WITH PREVIOUS MI AND IN 5 OF 7 PATIENTS WITH CAD BUT NO PRIOR MI. OVERALL, THERE WAS GOOD AGREEMENT BETWEEN GATED TOMOGRAPHY AND MRI FOR BOTH WALL MOTION (178/212, Κ =0.66) AND WALL THICKENING (184/212, Κ=0.69). (ABSTRACT TRUNCATED
ΜΕΛΕΤΗ ΤΗΣ ΒΙΟΣΥΝΘΕΣΗΣ ΤΩΝ ΠΟΛΥΑΜΙΝΩΝ ΣΤΟ ΒΑΚΤΗΡΙΟ ESCHERICHIA COLI
Η ΑΠΟΚΑΡΒΟΞΥΛΑΣΗ ΤΗΣ ΟΡΝΙΘΙΝΗΣ (ODC) ΑΠΟ E. COLI ΚΑΘΑΡΙΣΤΗΚΕ ΜΕΧΡΙ ΟΜΟΙΟΓΕΝΕΙΑΣΑΠΟ ΤΟ ΣΤΕΛΕΧΟΣ MG1655+PODC ΠΟΥ ΤΗΝ ΥΠΕΡΠΑΡΑΓΕΙ. ΠΡΟΣΔΙΟΡΙΣΤΗΚΕ Η Ν-ΤΕΛΙΚΗ ΑΜΙΝΟΞΙΚΗ ΑΛΛΗΛΟΥΧΙΑ ΤΗΣ ΚΑΙ ΠΡΟΒΛΕΦΘΗΚΕ Η ΠΡΩΤΟΤΑΓΗΣ ΔΟΜΗ ΤΗΣ ΑΠΟ ΤΗΝ ΑΛΛΗΛΟΥΧΙΑ ΤΟΥ ΓΟΝΙΔΙΟΥ ΤΗΣ. ΤΟ ΥΠΟΛΟΓΙΖΟΜΕΝΟ ΜΟΡΙΑΚΟ ΤΗΣ ΒΑΡΟΣ ΕΙΝΑΙ 79416 ΚΑΙ ΤΟ ΙΣΟΗΛΕΚΤΡΙΚΟ ΤΗΣ ΣΗΜΕΙΟ 5.59. ΟΙ ΑΝΤΙΣΤΟΙΧΕΣ ΠΕΙΡΑΜΑΤΙΚΕΣ ΤΙΜΕΣ ΕΙΝΑΙ 82000 ΚΑΙ 5.3. ΕΙΝΑΙ ΜΙΑ ΠΡΩΤΕΙΝΗ ΜΕ ΕΝΑΛΛΑΞ ΥΔΡΟΦΟΒΕΣ ΚΑΙ ΥΔΡΟΦΙΛΕΣ ΠΕΡΙΟΧΕΣ. ΣΧΗΜΑΤΙΖΕΙ ΣΥΣΣΩΜΑΤΩΜΑΤΑ ΜΕ ΤΗΝ ΠΑΡΟΔΟ ΤΟΥ ΧΡΟΝΟΥ. ΑΠΩΛΕΙΑ ΤΟΥ C-ΤΕΛΙΚΟΥ ΤΗΣ ΑΚΡΟΥ, ΚΑΘΩΣ ΚΑΙ ΜΕΤΑΛΛΑΞΗ ΤΗΣ LYS-347 ΣΕ SER Η ARG ΟΔΗΓΕΙ ΣΕ ΑΠΩΛΕΙΑ ΤΗΣ ΕΝΖΥΜΙΚΗΣ ΔΡΑΣΤΙΚΟΤΗΤΑΣ. ΕΝΕΡΓΟΠΟΙΕΙΤΑΙ ΑΠΟ GTP ΚΑΙ UTP, ΑΛΛΑ ΟΧΙ ΑΠΟ ATP ΚΑΙ CTP. ΤΟ CTP ΔΕΣΜΕΥΕΤΑΙ ΣΤΗΝ ODC ΕΞΕΙΔΙΚΕΥΜΕΝΑ, ΣΕ PH 8.5. H ODC ΦΩΣΦΟΡΥΛΙΩΝΕΤΑΙ IN VITRO ΚΑΙ IN VIVO. ΤΟ ΑΝΤΙΕΝΖΥΜΟ ΤΗΣ ODC ΑΠΟ THERMOPHILUS ΜΕ ΣΤΗΛΗ, ODC-SEPHAROSE ΚΑΙΜΕ ΑΝΟΣΟΚΑΤΑΚΡΗΜΝΙΣΗ, ΚΑΙ ΜΕΛΕΤΗΘΗΚΑΝ ΟΙ ΙΔΙΟΤΗΤΕΣ ΤΟΥ
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