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Lusitania Sacra, n. 47 (2023): Arte, arquitetura e religião no século XX

We present the case of a male patient on hemodialysis with a ruptured pseudoaneurysm in a brachiocephalic arteriovenous fistula (AVF) and with edema and pain in the right arm attended to in the emergency department. An ultrasonographic scan identified a ruptured pseudoaneurysm with hemorrhagic infiltration of the arm muscular tissues. We performed a percutaneous ultrasound-guided thrombin injection with an angioplasty balloon inflated in the lumen of the AVF achieving the pseudoaneurysm thrombosis. After 6 months of follow-up, the patient's arteriovenous access remains functional. Percutaneous ultrasound-guided thrombin injection assisted by an angioplasty balloon may be a good alternative to surgical intervention in the treatment of symptomatic growing pseudoaneurysms of the arteriovenous fistula with the benefit of preserving the vascular access.

Background: Hemodialysis access–induced distal ischemia consists of symptomatic extremity malperfusion after vascular access creation. It is usually caused by discordant vascular resistance, with arteriovenous shunting of a high blood volume from arterial into venous system and subsequent hand hypoperfusion. Less often, hemodialysis access–induced distal ischemia is caused by arterial stenosis. In these cases, access frequently has normal/low flow, radial pulse is usually absent and not recoverable with vascular access digital compression, diabetes is often present, and percutaneous transluminal angioplasty can be critical for access and limb salvage. Methods: Retrospective study conducted between June 2011 and February 2018 of patients with vascular access submitted to arterial percutaneous transluminal angioplasty for limb-threatening ischemia. Results: Twenty-nine patients were referred for arterial angiography after hemodialysis access–induced distal ischemia diagnosis and physical examination or ultrasound findings suggestive of arterial disease. In 11 patients, percutaneous transluminal angioplasty was not technically feasible. Among 18 treated patients, 83.3% had diabetes and 60% had skin ulcerations. Target arteries were radial (11), brachial (7), axillar (2), ulnar (2), and subclavian (1). Clinical success, defined as arteriovenous maintenance and wound healing/pain resolution, was observed in 12 patients (66.7%). Concomitant procedures included adjuvant banding ( n = 2) and finger amputation ( n = 1), and one reintervention was performed. No intra- or postoperative complications were reported. Conclusion: Hemodialysis access–induced distal ischemia is a serious complication of hemodialysis vascular access, with multifactorial etiology. Correct and timely diagnosis is crucial for maintaining access and limb salvage. Percutaneous transluminal angioplasty is a minimally invasive procedure that may be effective and long-lasting in carefully selected patients with ischemic complaints.

CSS was founded in 1974 and it has defined its mission, vision and values to support anddevelopthecommunityofRioTinto,Porto,andMatosinhos.CSSdevelopsservicesinseveralareas:childhoodandyoutheducation,elderlythathas3differentvalences(social center, day center and home support) and community intervention that comprises 24 projects within 6areas. Its major source of revenues are the grants and donations, mainly those from socialsecurity,whichhavebeenincreasingandthatallowtocoverthemaincostdriver–labor costs.The EBITDA of the center have been growing since2017.

The distal arteriovenous fistula (AVF) has less complications and better patency than the proximal fistula, when it works properly. The complications of outflow of the fistula are complex, and it is necessary to analyze all solutions to solve the problem. We introduce a novel approach to solve outflow problems of a radio-cephalic AVF by straightening of the forearm cephalic vein with drainage into the median basilic vein. info:eu-repo/semantics/publishedVersion

Objective: Permanent access in the form of a fistula is the preferred form of vascular access for most pediatric patients on maintenance hemodialysis (HD) therapy; however, the technical aspects of the procedure that are unique to the pediatric population, the expectation of a short waiting time for kidney transplantation and the need to cannulate every other day (with the pain and fear associated with it) limit its use. Our objective was to analyze the long-term outcomes of pediatric arteriovenous fistulas in our institution. Methods: A retrospective review was performed of all arteriovenous fistula (AVF) created in a HD population aged 0 to 18 years at a single institution from 2007 to 2019. Data abstracted included age, weight, etiology of renal failure, time on dialysis, central venous catheter history and transplantation history. Data were analyzed to determine the primary and secondary patency. Results: During the study period, 19 AVFs were performed in 16 patients, of whom 9 patients (56.3%) were male. Mean patient age was 12.3 years (range 5-17 years), and mean weight was 38.3kg (range 12-83kg). At the time of AVF creation, 9 patients were on dialysis and 7 patients had a central venous catheter (CVC), with a median length of CVC dependence of 10 months. Procedures performed included 4 radiocephalic fistulas, 11 brachiocephalic fistulas and 4 brachiobasilic. Five accesses failed to mature (26.3%). Mean follow-up was 6 years. The 2-year primary and secondary patency rates were 92.3% and 100%, respectively. The 4-year primary and secondary patency rates were 76.9% and 100%, respectively. No thrombosis was documented during follow-up. During the postoperative period, 10 patients (62.5%) received a kidney transplant, in a mean time of 23 months. Conclusions: AVFs demonstrate excellent long-term patency in pediatric HD patients. No significant complications were reported and no thrombosis occurred.

A casa de Janus / coordenação [de] Mário João Alves Chaves. - Lisboa : Universidade Lusíada, 2021. - ISBN 978-989-640-238-9. - P. 141-150.

Dissertação de Mestrado, Psicologia (Área de Especialização em Psicologia Clínica e da Saúde - Psicologia Clínica Dinâmica), Universidade de Lisboa, Faculdade de Psicologia, 2020 Submitted by Biblioteca FPIE-ULisboa (bibliorul@fpie.ulisboa.pt) on 2021-04-09T09:17:13Z No. of bitstreams: 1 ulfpie054220_tm.pdf: 581540 bytes, checksum: dd1b8f1803d3c54036e1b925899e8973 (MD5) Made available in DSpace on 2021-04-09T09:17:37Z (GMT). No. of bitstreams: 1 ulfpie054220_tm.pdf: 581540 bytes, checksum: dd1b8f1803d3c54036e1b925899e8973 (MD5) Previous issue date: 2020

Introduc��a��o: O stress ergono��mico associado a�� execuc��a��o procedimentos endovasculares leva o cirurgia��o vascular a assumir frequentemente um conjunto de posturas e movimentos para controlo imagiolo��gico do procedimento. Isto condiciona um aumento do risco a longo termo de desenvolvimento de patologia mu��sculo-esquele��tica. A utilizac��a��o de smart glasses (o��culos inteligentes) podera�� ter um papel na reduc��a��o deste risco, permitindo ao profissional controlar o procedimento sem necessidade de reposicionamento constante. Atrave��s da aplicac��a��o do questiona��rio Quick Exposure Check (QEC), compa- ramos o risco ergono��mico durante a realizac��a��o de procedimentos endovasculares com e sem a utilizac��a��o de smart glasses. Me��todos: O QEC foi aplicado por um observador externo durante a realizac��a��o de procedimentos endovasculares com e sem a utilizac��a��o de smart glasses Epson Moverio BT-35E��. Os dois grupos de procedimentos foram comparados relativamente ao score total no QEC e aos scores parciais que avaliam o risco relativo a diferentes segmentos anato��micos (coluna cervical, coluna lombar, ombro/brac��o e punho/ma��o). Os scores parciais de auto-percepc��a��o de stress e de ritmo de trabalho, avaliados pelo profissional, foram tambe��m comparados. Resultados: O QEC foi aplicado a um total de 12 procedimentos. Os procedimentos com utilizac��a��o de smart glasses (n=6) obtiveram um score total me��dio significativamente mais baixo no QEC (83.7 ��� risco ergono��mico baixo), comparativamente aos procedimentos sem utilizac��a��o de smart glasses (108.3 ��� risco ergono��mico moderado; p=0.009). Os scores parciais me��dios relativos a�� coluna cervical e lombar foram tambe��m significativamente mais baixos neste grupo (lombar: 11.3 vs 18; p=0.002) (cervical: 18 vs 26.7; p=0.002). Na��o se encontraram diferenc��as estatisticamente significativas para os scores parciais me��dios relativos ao ombro/brac��o e punho/ma��o, nem para os scores parciais me��dios de auto-percepc��a��o de stress e de ritmo de trabalho. Conclusa��o: A utilizac��a��o de smart glasses durante a cirurgia endovascular mostrou reduzir o risco ergono��mico, avaliado pela escala QEC, de moderado para baixo. Esta reduc��a��o traduz-se principalmente numa diminuic��a��o do risco de patologia mu��sculo-esquele��tica a ni��vel da coluna e do pescoc��o., Angiologia e Cirurgia Vascular, Vol 15 No 3 (2019): September

Vascular access dysfunction is a serious problem in dialysis units. Some patients have complex dysfunctions that are difficult to resolve. In this article, we report the case a of two patients with radiocephalic arteriovenous fistulae (RC-AVF) who had stenosis/occlusion of the forearm median vein and where we used the basilic vein of the forearm as a solution. We reviewed the use of this surgical solution in RC-AVF. Two male patients on hemodialysis exhibited stenosis/occlusion of the forearm median vein. The forearm basilic vein was isolated and rotated toward the forearm median vein in order to solve RC-AVF problems. One patient had fistula thrombosis 5 months after the procedure, while for the other patient, the fistula continues to work without problems. Literature describes only a few cases using the forearm basilic vein or the brachial vein for fistula recovery. This procedure increased the patency of fistulas. This approach has been proven to be a good solution for solving outflow problems using the superficial or deep veins, increasing fistula patency and avoiding the need to place a central venous catheter and all the related complications.

Dysfunction of arteriovenous access for hemodialysis is a challenge for the vascular surgeon. Some patients have complex vascular access with problems that are difficult to solve. Careful analysis of the vascular network with ultrasound and dissection of the veins during surgery can help to identify the best option for each access. We introduce and discuss the case of creation of a radio-cephalic fistula with outflow into the brachial vein in 64-year-old hemodialysis male patient. This technique enables extending fistula patency, arterializing the brachial vein, and improves cost efficiency.

The vascular access is the mainstay of hemodialysis. Arteriovenous fistula has been prioritized as the first choice of long-term vascular access for its inferior rate of complications and improved patient survival. Rope ladder and buttonhole venipuncture are the most common techniques for arteriovenous fistulae cannulation. Much of the concern regarding buttonhole cannulation is the increased risk for potentially severe systemic infections. Increased risk for stenosis and thrombosis has been addressed but not confirmed. We discuss two cases of stenosis and thrombosis related to buttonhole puncture which heralded angiography intervention, raising awareness for the demand of close surveillance of arteriovenous fistulae when using buttonhole cannulation.

The increasing survival of hemodialysis patients results in the depletion of superficial venous capital justifying the use of the basilic vein. Many groups still prefer an arteriovenous graft due to transposition complexity and the time needed to achieve maturation. In this work we review the results of our series of basilic vein transpositions (BVT). BVTs were performed in two stages: first, creation of the fistula; second, transposition of the vein using three small incisions in the arm. All patients had to have direct arterialization of the basilic vein, therefore, patients with previous ipsilateral wrist fistulas also followed a two-stage protocol. Data were retrospectively revised from all transposition procedures made between September 2005 and November 2012. Patency and complication rates were the primary outcomes evaluated. A total of 276 basilic veins were transposed. Usage rate was 82.2%. 8% (N = 22) of the fistulas were never used due to thrombosis. Secondary patency rates at 1 and 2 years were, respectively, 84% and 66.3%. Complications occurred in 61.6% (N = 170) of fistulas and 65.9% (N = 112) of which had to undergo surgical or endovascular revision. The most frequent complication was vein stenosis (39.7% of late complications, N = 92). Albeit its greater technical complexity, the transposed basilic vein represents a hemodialysis access with good patency rates. Complication rates, although high, are less than those of CVC or prosthetic grafts. These results support the use of the transposed basilic vein as hemodialysis access after the brachiocephalic fistula.

The percutaneous transluminal balloon angioplasty or cephalic vein transposition is the treatment for cephalic arch stenosis. In some cases, rotation of the external jugular vein may be a good option for the cephalic arch problems. We describe a new technique to treat cephalic arch stenosis. The technique enables the cephalic arch and subclavian vein to be bypassed altogether through the rotation of the external jugular vein. It consists of 3 small incisions, thus causing minimal surgical damage.

Dysfunction problems with vascular access are a concern to patients and dialysis units. The vascular surgeon should analyse such dysfunction and perform a careful assessment of the vascular network in order to find new fistula layouts. We introduce and discuss the case of creation of a radio-cephalic fistula with outflow into the forearm basilic vein through rotation of the forearm basilic vein toward the cephalic vein in the forearm of an 88-year-old hemodialysis male patient. This technique enables extending fistula patency and improves cost efficiency.

Vascular access dysfunction is a serious problem in dialysis units. Some patients have complex dysfunctions that are difficult to resolve. In this article, we report the case a of two patients with radiocephalic arteriovenous fistulae (RC-AVF) who had stenosis/occlusion of the forearm median vein and where we used the basilic vein of the forearm as a solution. We reviewed the use of this surgical solution in RC-AVF. Two male patients on hemodialysis exhibited stenosis/occlusion of the forearm median vein. The forearm basilic vein was isolated and rotated toward the forearm median vein in order to solve RC-AVF problems. One patient had fistula thrombosis 5 months after the procedure, while for the other patient, the fistula continues to work without problems. Literature describes only a few cases using the forearm basilic vein or the brachial vein for fistula recovery. This procedure increased the patency of fistulas. This approach has been proven to be a good solution for solving outflow problems using the superficial or deep veins, increasing fistula patency and avoiding the need to place a central venous catheter and all the related complications.

Vascular access dysfunction is a serious problem in dialysis units. Some patients have complex dysfunctions that are difficult to resolve. In this article, we report the case a of two patients with radiocephalic arteriovenous fistulae (RC-AVF) who had stenosis/occlusion of the forearm median vein and where we used the basilic vein of the forearm as a solution. We reviewed the use of this surgical solution in RC-AVF. Two male patients on hemodialysis exhibited stenosis/occlusion of the forearm median vein. The forearm basilic vein was isolated and rotated toward the forearm median vein in order to solve RC-AVF problems. One patient had fistula thrombosis 5 months after the procedure, while for the other patient, the fistula continues to work without problems. Literature describes only a few cases using the forearm basilic vein or the brachial vein for fistula recovery. This procedure increased the patency of fistulas. This approach has been proven to be a good solution for solving outflow problems using the superficial or deep veins, increasing fistula patency and avoiding the need to place a central venous catheter and all the related complications. info:eu-repo/semantics/publishedVersion

Background: The definition of significant stenosis (SS) remains controversial. Methods: We retrospectively reviewed 1,040 consultations. SS was defined in the presence of clinical and echo-Doppler (DDU) criteria: Qa 25%; RI >0.7 in the feeding artery or absolute minimal luminal stenosis diameter Results: Two hundred twenty-one arteriovenous fistulas (AVFs) were included: 58.8% had SS, 18.6% had BS, and 22.6% had no dysfunctional access (ND). SS had a significantly higher thrombotic events than BS and ND (13.1 vs. 4.4%, p = 0.018). The annual thrombosis rate was 0.007, 0.037, and 0.004 in the ND, SS, and BS, respectively. AVF cumulative survival at 5 years was significantly lower in SS (89.5%) compared to BS (100%) and ND (97.4%; p = 0.03). BS had an HR for AVF failure of 1.1, p = 0.955, while the SS presented an HR of 5.9, p = 0.09. Conclusion: AVF clinical monitoring with additional DDU criteria appear to be appropriate for therapeutic referral.

Purpose The aim of this study is to validate the current applicability of arteriovenous access banding in high flow access (HFA) and/or haemodialysis access-induced distal ischaemia (HAIDI). Methods This retrospective study was conducted at the GEV (Grupo de Estudos Vasculares) vascular access centre. The clinical records of consecutive patients undergoing banding for HAIDI and HFA symptoms, between June 2011 and January 2015, were reviewed until April 2015. All vascular access patients’ consultation records and surgical notes were reviewed. We analysed and compared patients’ age, gender, comorbidities, symptoms and intraoperative ultrasound control. We defined technical failure as recurrence of symptoms, requiring new banding. Excessive banding, access thrombosis, rupture and false aneurysm development were registered as complications. Primary clinical success was defined as improvement of symptoms or effective flow reduction after banding, with no need for reintervention. If one reintervention was necessary, we have defined it as secondary clinical success. Results Overall, 119 patients underwent banding: 64 (54%) with HAIDI and 55 (46%) with HFA. The HAIDI group was significantly older (65 ± 13 years compared with 56 ± 22 years, p = 0.001) and had significantly greater number of patients with diabetes (56% vs 24%, p = 0.004). Primary success was achieved in 85 patients (71.4%) and the secondary success rate was 84.9%. Older age (p = 0.016) and intraoperative ultrasound control (p = 0.012) were significantly associated with primary success. Conclusions Our results do not corroborate the high incidence of thrombosis previously reported as associated with AV access banding and suggest that ultrasound control is crucial for preventing technical failure. The procedure was effective on both compared groups.

The exhaustion of superficial venous patrimony or reduced diameter of superficial veins usually prevents patients from having an arteriovenous fistula created. In such cases, using deep vessels can be a more viable option as opposed to an arteriovenous graft. We describe a new approach for the brachio-brachial arteriovenous fistula creation technique. It consists of 3 small incisions, thus causing minimal surgical damage. We have found it to be better tolerated by the patients and well received by dialysis nurses. This procedure also allows improved access for cannulation and more available puncture sites. info:eu-repo/semantics/publishedVersion

Dysfunction problems with vascular access are a concern to patients and dialysis units. The vascular surgeon should analyse such dysfunction and perform a careful assessment of the vascular network in order to find new fistula layouts. We introduce and discuss the case of creation of a radio-cephalic fistula with outflow into the forearm basilic vein through rotation of the forearm basilic vein toward the cephalic vein in the forearm of an 88-year-old hemodialysis male patient. This technique enables extending fistula patency and improves cost efficiency. info:eu-repo/semantics/publishedVersion

Vascular access is essential for the implementation of hemodialysis (HD). The arteriovenous fistula (AVF) can be constructed in various locations using various veins. However, the quality of the veins will influence the construction site, as well as the functioning of the AVF. Careful analysis of the vascular network allows options for the development of new fistulas presentations. We present and discuss the case of a woman aged 69 years in HD in which a brachial-cephalic fistula with drainage to basilic vein was created, through rotation of the cephalic vein on the forearm level. This kind of access serves to prolong the time spent dialyzing through native fistulae, with their reduced complications and greater cost-effectiveness.

Purpose Hemodialysis (HD) is the main treatment modality in stage 5 chronic kidney disease, and vascular access planning is a crucial step in the path to dialysis treatment. Beyond detailed patient history and physical examination, duplex ultrasound (DU) evaluation is essential in preoperative vascular mapping. Methods A retrospective descriptive nonrandomized study was performed and included 108 end-stage kidney disease patients referred from eight HD centers to be assessed for creation of an arteriovenous (AV) access (AV fistula or AV graft). We assessed primary failure, primary unassisted patency (PP) and primary assisted patency (PAP) rates and cumulative survival of AV accesses at 6 and 12 months. Results We created 86 AV accesses of which 79 (91.9%) were AV fistulas (AVFs) (29 distal AVFs, 49 proximal AVFs and 1 femorofemoral AVF) and 7 (8.1%) arteriovenous grafts (AVGs). Fifteen percent (15%) (n = 12) of primary failure occurred in the AVF group. Any case of primary failure was observed between AVGs. In the AVF group, PP at 6 months was 63.8% and at 12 months was 48.3%, PAP was 80.7% at 6 and 12 months. PP excluding primary failures was 73.0% and 55.3% at 6 and 12 months, respectively. The cumulative survival at 6 and 12 months was 80.7%. In the AVG group, PP at 6 months and 12 months was 66.7%, PAP and cumulative survival at 6 and 12 months were of 100%. Conclusions This study demonstrates that preoperative vascular mapping with a patient-centered approach may be critical to achieve good outcomes allowing the increase in AVF access.

Vascular access is essential for the implementation of hemodialysis (HD). The arteriovenous fistula (AVF) can be constructed in various locations using various veins. However, the quality of the veins will influence the construction site, as well as the functioning of the AVF. Careful analysis of the vascular network allows options for the development of new fistulas presentations. We present and discuss the case of a woman aged 69 years in HD in which a brachial-cephalic fistula with drainage to basilic vein was created, through rotation of the cephalic vein on the forearm level. This kind of access serves to prolong the time spent dialyzing through native fistulae, with their reduced complications and greater cost-effectiveness. info:eu-repo/semantics/publishedVersion

The discovery of the biological effects of carbon monoxide (CO) in recent years strongly suggests that CO could find applications as a therapeutic agent. CO is a highly toxic gas when used at industrial doses, due in part to its binding affinity to hemoglobin. Since hemoglobin binds CO with the highest affinity in vivo, it also constitutes a major barrier to the delivery of CO to tissues in need of therapy. A method of delivering CO that can bypass hemoglobin is the use of pro-drugs or CO carriers, called CO-releasing molecules (CO-RMs) that become activated and release CO in tissues in need of treatment. Organometallic carbonyl complexes are best suited to play the role of CO carriers, and indeed the natural CO carrier molecules hemoglobin and myoglobin belong to this class of chemical compounds. Here we describe the preparation of novel molybdenum CO-RMs of general formula Mo(CO)3(CNCR′R″CO2R‴)3 (R′, R″ = H, Me, iPr, CH2Ph, CO2Li, −CH2CH2–, −CH2(CH2)3CH2–; R‴ = H, Li), which present favorable druglike c...

Decarbonylation of the tertiary aldehydes 4-ethyl-4-formyl-hexanenitrile (2) and 2-methyl-2-phenylpropanal (4) promoted by dioxygen occurs at room temperature only if suspended in water probably via the sequential acyl radical–CO liberation–tertiary radical that is promoted by an ‘on water’ process originating preferentially from the corresponding tertiary hydroperoxide.

Introdução: Os acessos vasculares são responsáveis por elevada morbilidade nos doentes em hemodiálise. A fístula arteriovenosa (FAV) representa o acesso vascular com menor taxa de complicações, pelo que a Consulta de Acessos Vasculares para hemodiálise procura promover o aumento da sua taxa de patência. Métodos: avaliação retrospectiva dos motivos de referenciação à consulta entre 01-01-2008 e 31-12-2009, do resultado das intervenções e análise dos factores relacionados com a patência da FAV. Resultados: Avaliaram-se 697 doentes (58% homens, 30% diabéticos, idade média 64±15 anos) referenciados para construção de acesso (71%), suspeita de estenose (14%), síndrome de roubo (6%) pseudoaneurismas (4%) e hipertensão venosa (HTV) (3%). Os acessos construídos foram FAV simples (n=514; 91% dos doentes), transposição da veia basílica (n=40) e pontagem arteriovenosa com prótese (n=10). A taxa de patência global (às 4 semanas) foi 83% (75%, 93% e 40% respectivamente nas FAVs, transposições e pontagens). A localização proximal da FAV (p Background: The vascular access is responsible for high morbidity in for hemodialysis patients. Arteriovenous fistula (AVF) provides the vascular access with lower complication rate, so the Consulta de Acessos Vasculares for hemodialysis promotes actions to increase its patency rate. Methods: Retrospective study of the causes for referral to consultation between 01/01/2008 and 31/12/2009, outcome of proposed interventions and factors favoring AVF patency. Results: We evaluated 697 patients (58% male, 30% diabetic, mean age 64 ± 15 years) referred for construction of access (71%), suspicion of stenosis (14%), steal syndrome (6%), pseudoaneurysm (4%) and venous hypertension (HTV) (3%). The constructed access were simple AVF (n=514, 91% of patients, transposition of the basilic vein (n=40) and prothesic arteriovenous graft (n=10). The global access patency rate (at 4th week) was 83% (with 75%, 93%, 40% for AVFs, transposition and grafts, respectively). Proximal location of AVF (p

Vascular access is essential for the implementation of hemodialysis (HD). The arteriovenous fistula (AVF) can be constructed in various locations using various veins. However, the quality of the veins will influence the construction site, as well as the functioning of the AVF. Careful analysis of the vascular network allows options for the development of new fistulas presentations. We present and discuss the case of a woman aged 69 years in HD in which a brachial-cephalic fistula with drainage to basilic vein was created, through rotation of the cephalic vein on the forearm level. This kind of access serves to prolong the time spent dialyzing through native fistulae, with their reduced complications and greater cost-effectiveness.

Dissertação apresentada para obtenção do Grau de Mestre em Informática, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia In recent years we have observed an increased use of the Internet as a means for transmitting large content. There have been several technology attempts to attack this problem, including costly distribution networks and, more recently, peer to peer (P2P) protocols. Amongst these P2P protocols, BitTorrent has proven itself as an effective means for transmitting large content items and today enjoys great popularity. Numerous researchers have analyzed BitTorrent and proposed concepts and models to enhance its reliability, efficiency and fairness. Further, there are proposals to extend BitTorrent to support on-demand multimedia streaming. In this Dissertation we present Bitocast, a content distribution system that combines IP Multicast and BitTorrent protocols in order to achieve a more efficient usage of an Internet Service Provider’s network and reduce download time when serving large sets of contents to large audiences.

Mestrado em Engenharia Alimentar - Qualidade e Segurança Alimentar - Instituto Superior de Agronomia Volatile compounds were identified by gas chromatography–mass spectrometry (GC-MS) and, it was determined the amount of ascorbic acid by high performance liquid chromatography (HPLC) present in juice samples and soft drinks in different types of packages, at different times and at different temperatures of ageing (approximately 22ºC and 40°C). The freezing effect of the samples has also been tested. After optimization of the sample preparation method by micro-extraction in the solid phase, a DVB/CAR/PDMS fibre was used at an extraction temperature of 40°C, during 40 min and were optimized the conditions in the chromatograph. At room temperature, both beverages had suffered lower aromatic profile variations in Tetrapak package. At 40°C, juice packages react similarly concerning the ascorbic acid content as well as the aromatic profile, however, in the soft-drink, the loss in ascorbic acid is much lower in the PET package, and for the aromatic profile, Tetrapak is the package with lower variations. All of the samples, for both ageing studies, had statistically significant variations (p

This paper presents the concept and most of the research undertaken all over the world for the development of a bio-artificial pancreas (BAP) device over the last 30 years. The devices studied, meant to mimic the insulin secretion of the natural organ, were diverse and have been reviewed. Allogeneic or xenogeneic cells or cell clusters have been separated from the host's immune system by synthetic biocompatible semipermeable membranes to prevent the need, of the host, for immune-suppressing regimens. The biocompatible polymer used as a barrier and its intrinsic characteristics, the cell immobilization or suspension media, the existence or not of co-immobilized molecules or cells, the number of devices used and the implantation site, were addressed.

Submitted by lara martins (laramartins.defi@chporto.min-saude.pt) on 2011-04-20T08:58:27Z No. of bitstreams: 1 sdarticle.pdf: 42469 bytes, checksum: f13bf76e25a7ac8bb39c7ddb5781d8a0 (MD5) Made available in DSpace on 2011-04-20T08:58:27Z (GMT). No. of bitstreams: 1 sdarticle.pdf: 42469 bytes, checksum: f13bf76e25a7ac8bb39c7ddb5781d8a0 (MD5) Previous issue date: 2003-05

No other form of therapy, whether medical or surgical, has an impact comparable to heart transplantation on the quality of life and survival of selected patients with severe heart failure. In the EU and in the USA about 10 patients per million of population are transplanted each year. In Portugal, a country with a population of 10 million, 100 patients should be transplanted each year, but only 12 patients were in fact transplanted in 1999. We rank 17th, in terms of the rate of heart transplantation per million of population, among the 23 European countries with registries of this activity. This is due to structural and organizational deficiencies of three main types: the lack of professional teams dedicated to severe heart failure treatment and heart transplantation; the lack of infrastructure, particularly heart failure wards and heart failure outpatient clinics; and the inappropriate distribution of the tasks associated with heart transplantation and patient follow-up. We present an estimate of the number of potential heart transplant candidates in Portugal, based on the EPICA study and a prediction of the resources needed for a successful heart transplantation program serving a population of 2 million. This was based on what is known of the natural history, morbidity and mortality of severe heart failure, on our own experience in this field, and finally on the experience of a large international heart transplantation center. The recommendations of the British Transplantation Society and those of the Department of Cardiothoracic Surgery of Stanford University were also taken into account.

The authors describe a case in which an exostosis of the femur produced thrombosis of the third portion of the right femoral artery in a male of 34.

A review of the surgical management of 21 patients presenting fractures, dislocations of the knee-joint associated with arterial injury, or both has been presented herein.