Status and characterisation of COMPASS RICH-1 Albrecht, E.; Baum, G.; Birsa, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2005, Letnik:
553, Številka:
1
Journal Article
Recenzirano
COMPASS RICH-1, a gas-radiator RICH detector with large transversal dimensions, which makes use of MWPC with CsI photocathodes as photon detectors, is in operation at COMPASS since 2001. The ...behaviour of the detector components is optimised and fully understood. The characterisation of the detector is now complete. We report about the detector status and its response in the COMPASS environment.
We present a VLSI implementation of a hardware sorting algorithm for continuous data sorting. The device is able to continuously process an input data stream while producing a sorted output data ...stream. At each clock cycle, the device reads and processes a 48-bit word, 24 bits for the datum and 24 bits for the associated tag. The data stream is sorted according to the tags preserving the order of words with identical tags. Sequences up to 256 words are completely sorted and longer sequences are partially sorted. The maximum operation frequency is 50 Mwords/s. The architecture is based on a chain of identical elementary sorting units. A full custom design exploits the highly regular architecture to achieve high area and time performance. We describe the algorithm and give architectural details.
Platelet activation has been demonstrated in experimental and clinical models of ischemia-reperfusion, but the underlying mechanism is still unclear. We mimicked the ischemia-reperfusion model in ...vitro by exposing platelets to anoxia-reoxygenation (A-R) and evaluated the role of oxygen free radicals (OFRs), which are usually produced during the reperfusion phase, in inducing platelet activation.
Human platelets were exposed to 15 and 30 minutes of anoxia and then reoxygenated. Compared with control platelets kept in atmospheric conditions, platelets exposed to A-R showed spontaneous platelet aggregation (SPA), which was maximal after 30 minutes of anoxia. Superoxide dismutase (SOD) (-74%, P < .005), catalase (-67%. P < .005). SOD plus catalase (-82%, P < .005), and the hydroxyl radical (OH0) scavengers mannitol (-66%, P < .005) and deoxyribose (-55%, P < .005) inhibited SPA. Platelets that had undergone A-R released superoxide anion (0-2), as detected by lucigenin chemiluminescence. Also, platelets exposed to A-R and incubated with salicylic acid generated 2.3- and 2,5-dihydroxybenzoates, which derive from salicylic acid reaction with OH0. SPA was significantly inhibited by the cyclooxygenase enzyme inhibitors aspirin and indomethacin: by SQ29548, a thromboxane (Tx) A2 receptor antagonist; by diphenyliodonium an inhibitor of flavoprotein-dependent enzymes: and by arachidonyl trifluoromethyl ketone, a selective inhibitor of cytosolic phospholipase A2. Platelets exposed to A-R markedly generated inositol 1,3,4-trisphosphate and TxA2, which were inhibited by incubation of platelets with SOD plus catalase.
This study shows that platelets exposed to A-R intrinsically generated 0-2 and OH0, which in turn activate arachidonic acid metabolism via phospholipases A2 and C, and provides further support for the use of antioxidant agents as inhibitors of platelet function in ischemia-reperfusion models.
P30 A STONE ON THE HEART Viele, A; Lombardi, M; Trivisonno, A ...
European heart journal supplements,
05/2023, Letnik:
25, Številka:
Supplement_D
Journal Article
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Odprti dostop
Abstract
We report a case of a 71–year–old female patient presented to our observation with worsening episodes of chest pain associated with cold sweat and spontaneous regression. Seven months ...earlier, the patient had undergone mitral valve replacement surgery with bioprosthesis for severe insufficiency. Pre–operative coronary angiography had documented the absence of significant lesions of the coronary arteries. Four months after the operation, hospitalisation was necessary due to an infective endocarditis on the prosthetic valve, effectively treated with specific antibiotic therapy. The patient came to the Emergency Department reporting episodes of stress related angina, lasting for a few days. The ECG documented sinus rhythm and non–specific anomalies of the ventricular repolarization phase. The haematochemical tests showed a minimal increase in the HS troponine values. Ultrasound documented normal left ventricular dimensions, no regional kinetic abnormalities with normal global systolic function and good functioning of the mitral bioprosthesis. The patient was admitted in our department of cardiology for further investigations. The next day the patient complained of severe oppressive chest pain with ECG evidence of diffuse ST–T segment depression and elevation in aVR and V1. Blood pressure was 170/90 mmHg and ultrasound showed apex hypokinesia with severely reduced systolic function. Nitrate s.l was administered with gradual improvement of symptoms and normalisation of the ECG. The patient underwent coronary angiography but during the first injection of contrast test, an anomalous stagnation of the contrast was highlighted in the aorta. It was urgently decided to perform aortic CT scan. The examination showed the presence of a voluminous pseudoaneurysm starting from the aortic bulb, partially thrombosed, which compressed the left main and the origin of the circumflex artery. The patient was therefore subjected to cardiac surgery the following day, with a good follow–up result one month after discharge.
Abstract
The infective endocarditis (IE) has a significant impact on mortality rate in the first year after diagnosis, despite the improvements in early diagnosis and therapy. Embolic complications ...cause worsening of patient’s prognosis and they occur in the 20–50% of cases, with a risk of new embolic events after the initiation of antibiotic therapy rated between 6 and 12%. Echocardiographic characterization of vegetation has an important role in the definition of the embolization risk, it is documented that vegetation with dimension more than 10 mm are at higher risk. Several characteristic of the patient (diabetes, previous embolization, atrial fibrillation) determine the increase of the embolization risk, as well as the initiation of antibiotic therapy. We describe the case of a 64 y.o. man with chronic coronary syndrome (previous PCI) and previous Bentall–De Bono intervention for ascending aorta aneurysm. Patient was under anticoagulant therapy with DOAC due to atrial fibrillation. He was admitted to the emergency department for intermittent fever during the last three months, dyspnea and fatigue. Blood test showed neutrophilic leukocytosis and increased value of inflammatory markers. Transthoracic echography revealed an hyperechoic image on the ventricular side of the aortic prosthesis. The diagnosis of infective endocarditis was confirmed with transesophageal echocardiography, and empiric antibiotic therapy was initiated. Cardiac surgeon suggested follow up and new evaluation after three weeks of therapy. Clinical course was complicated by acute abdomen. The CT exam revealed dilation of a distal tract of superior mesenteric artery (maximum axial diameter was 10 mm) associated with distal thrombosis extended for 6 mm. The transthoracic echocardiogram showed absence of the vegetation on aortic prosthesis previous documented. Therapy with intravenous infusion of unfractionated heparin was administrated for three weeks, but the control TC showed persistence of the thrombotic occlusion of superior mesenteric artery so the case was discussed with Vascular Surgery team. They decided to treat patient with embolization and aneurysmectomy surgery (cultures were negative). This clinical case demonstrates that embolic complication of infective endocarditis, even on proper antbiotic therapy and close monitorization, are unpredictable and can cause the worsening of patient’s clinical course.
Abstract
Il SARS–CoV2 è trasmesso tra gli umani attraverso particelle respiratorie e l’infezione può determinare un largo spettro di manifestazioni cliniche. Precedenti studi hanno dimostrato il ...ruolo centrale dell’immunità cellulo–mediata nel limitare la gravità delle infezioni da virus respiratori. I linfociti T–helper CD4+ sono coinvolti in funzioni di coordinazione e regolazione dell’immunità anti–virale: determinano lo sviluppo di anticorpi neutralizzanti ad alta affinità e la differenziazione dei centri germinali a cellule B in cellule della memoria secernenti anticorpi con lunga vita. Nessun dubbio sul ruolo cruciale della risposta a cellule T durante l’infezione da SARS–CoV2 o dopo la vaccinazione. Descriviamo il caso di un paziente di 39 anni, vaccinato con ChAdOx1–S. Dopo due settimane il paziente accusava dispnea e febbricola. Il test molecolare per SARS–CoV2 era negativo; agli esami ematici la PCR era aumentata. La TC del torace escludeva embolia polmonare e rivelava pattern a vetro smerigliato bilaterale, come da flogisi. All‘ecocardiogramma i parametri erano nella norma. L’ECG mostrava tachicardia sinusale. Il paziente veniva dimesso dal PS con terapia cortisonica. Una settimana dopo i sintomi peggiooravano. Una nuova TC torace mostrava difetti di opacizzazione di rami secondari dell’arteria polmonare ed aspetto bilaterale a vetro smerigliato. Si iniziava terapia con EBPM ed antibiotici a largo spettro. Il test molecolare e la sierologia per SARS–CoV2 erano negativi. Negativi i test per Mycoplasma, Chlamydia, Legionella e CMV DNA. L’emocromo mostrava ridotti linfociti (6,8%) con neutrofilia relativa (90,4%), ma normale valore dei bianchi. La TC–HR mostrava aspetto “crazy paving” bilaterale suggestivo per infezione virale o micotica (pattern come da infezione da Pneumocystis Jiroveci). Il test per HIV aveva esito positivo; alla tipizzazione linfocitaria ridotti i livelli di linfociti T–Helper (CD3+/CD4+) e rapporto CD3+/CD4+ 0%. Per il rapido deterioramento del quadro clinico il paziente veniva trasferito in terapia intensiva. Dopo 30 giorni dalla diagnosi di AIDS il paziente giungeva ad exitus. Il ruolo dei linfociti T nello sviluppo di anticorpi neutralizzanti e di cellule della memoria durante l’infezione da SARS–CoV2 è la chiave nella strategia di vaccinazione per ridurre il dilagare della pandemia, tuttavia nel nostro paziente questo meccanismo non ha funzionato rivelando il deficit del suo sistema immunitario da una latente infezione da HIV.
Abstract
Coronary artery kink is a variant of anomalous coronary artery, not related to vessel disease. Often it is associated with coronary artery tortuosity (CAT) and fibromuscular dysplasia. The ...pathogenesis and clinical implications are not fully understood. Kinks are hypothesized to cause coronary blood flow alterations that can results in ischemia and even in acute coronary syndrome. It is speculated that coronary artery kinks are most often caused by guide wire straightening and seen after wiring the artery, but that is not always the case. We describe the case of a 55 years old woman, with familiar history of CAD. In 2019 she had percutaneous Patent Foramen Ovale closure intervention. She presented to the Emergency Department complaining chest pain radiating into the neck. The ECG was normal, but Troponin I levels were mildly elevated (2,1 ng/ml) and ipokinesia of basal and mid segment of the anterior intraventricular spetum was found at the ecoscopy. The patient was admitted to Cardiology department with diagnosis of unstable angina and urgent coronary angiography was performed. At a first glance the coronary arteries did not exhibit significant arteriosclerotic or thrombotic changes. However, upon a closer review, a focal kink of the mid left descending coronary artery was found. This coronary kink folded the LAD during systole causing a transient stenosis that resolved during diastole. Management of coronary kinks is controversial. In the past, literature suggested treatment with coronary stenting as one of the management options. However there are reported cases of adverse outcomes, such as shifting of kink proximally, requiring an additional stenting. We decided to treat patient with medical approach: beta–blockers at the tolerated doses was initiated, in addition to ACE–Inibithor, Aspirin and statin. Stenting of the coronary artery was not a choice, due to the possibility of shifting (as described in literature) and stent fracture. At a one month follow up the patient presented asymptomatic for angina, palpitation or dyspnea. Even if rarely coronary artery kink is a potential cause of myocardial ischemia and its treatment is often challenging to improve patient quality of life and to prevent adverse cardiac event.
Abstract
Coronary artery fistula (CAF) is defined as anomalous communication between coronary arteries and cardiac chamber or a major thoracic vessel. CAF are a rare coronary anomaly, mostly ...congenital, first described by Krause in 1856. In literature the incidence in general population is approximately 0,002%. Detection of CAF during coronary angiography is usually accidental. In 50% of cases CAF originate from right coronary artery, in 30% they originate from LAD, while in the rest of the percentage CAF originate from left circumflex artery. CAF drain into low–pressure chamber (right ventricle or right atrium, superior Vena Cava or pulmonary artery). We can distinguish CAF into little or medium sized, usually with silent clinical course, and large sized CAF, with variable clinical signs, depending on the extent of the shunt and on the hemodynamic overload of the receiving chamber. We describe the case of a 57 y.o woman with hypertension, admitted for femur fracture. ECG showed bifasic T waves in the anterior leads, already described in a previous ECG. Normal systolic function and no valvular defect were found on the echocardiogram. Patient was asymptomatic. Coronary angiography documented normal coronary arteries, with a double coronary fistula: the first from a septal branch of posterior descending and the second one from distal branches of the first diagonal. Even if CAF have often a favorable clinical course with no relevant consequences for the patient, it’s crucial to obtain more information about their functional implication and their anatomic connections. Indeed, rare cases of sudden cardiac death have been described in patients with CAF involved in myocardial ischemia based on the theft syndrome mechanism. Echocardiographic evaluation of the patient to detect associated congenital abnormalities, pressure overload of the receiving chambers and the extent of the shunt on the coronary angiography are crucial for the proper management of CAF. In the case described above we decided to optimize therapy adding beta–blocker (to reduce the overload caused by the two coronary fistula).
The radiator gas and the gas system of COMPASS RICH-1 Albrecht, E.; Baum, G.; Bellunato, T. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2003, Letnik:
502, Številka:
1
Journal Article
Recenzirano
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The design of the COMPASS RICH-1 gas system, its operational modes, the cleaning setups for the preparation of the radiator gas and transmission measurement installations are described. The gas ...system in presently fully operational and satisfactory transmission of VUV light through the radiator gas has been reached.
