Design of a bifurcated stent graft, with its accompanying delivery system.

Abdominal Aortic Aneurysms (AAA) haemorhaging is a life-threatening disease. An aneurysm is a permanent swelling of an artery due to a weakness in its wall. Current surgical repair involves opening the chest or abdomen, gaining temporary vascular control of the aorta and suturing a prosthetic graft to the healthy aorta within the aneurysm itself The outcome of this surgical approach is not perfect, and the quality of life after this repair is impaired by postoperative pain, sexual dysfunction, and a lengthy hospital stay resulting in high health costs. All these negative effects are related to the large incision and extensive tissue dissection. Endovascular grafting is an alternative to the standard surgical method. This treatment is a less invasive method of treating aortic aneurysms. It involves a surgical exposure of the common femoral arteries where the stent graft can be inserted through by an over-the-wire technique. All manipulations are controlled from a remote place by the use of a catheter and this technique avoids the need to directly expose the diseased artery through a large incision or an extensive dissection. The proposed design method outlined in this project is to develop the endovascular approach. The main aim is to design an unitary bifurcated stent graft (1 e- bifurcated graft as a single component) to treat these Abdominal Aortic Aneurysms. This includes the delivery system and deployment mechanism necessary to first accurately position the stent graft across the aneurysm sac and also across the iliac bifurcation, and secondly fix the stent graft in position by using expandable metal stents. Thus, excluding the aneurysm from the circulation and therefore preventing rupture. Miniaturisation is a critical aspect of this design, as the smaller the crimped stent graft the easier to guide through the vascular system to the desired location. Biocompatibility is an important aspect. The preferred materials for this prosthesis are to use Shape Memory Alloys for the stent and a multifilament fabric for the graft. A taper design is applied for the geometry as this gives a favourable flow characteristic and reduced wave reflections. Adequate testing of the stent graft to prove its durability and the ease of the method of deployment is a prerequisite. A bench test facility has being designed and build to replicate the cardiovascular system and the disease in question aortic aneurysms at the iliac bifurcation. The testing here shows the feasibility of the proposed delivery system and the durability of the stent graft across the aneurysm sac. Finally, these endovascular treatments offer the economic advantage of short hospital stays or even treatment as an outpatient, as well as elimination of the need for postoperative intensive care The risk of developing an aneurysm increases with age, that is one of the mam reasons to look for less invasive ways of treating aneurysms. Consequently, there is enormous pressure to develop and use these devices rapidly.

Resposta pressórica após exercício resistido de diferentes segmentos corporais em hipertensos

FUNDAMENTO: O exercício resistido tem sido atualmente recomendado como componente adjunto do exercício aeróbico no programa de treinamento físico direcionado ao tratamento e controle da hipertensão arterial sistêmica (HAS). Entretanto, o mesmo ainda não tem sido amplamente incorporado na prática clínica, possivelmente pela escassez de evidências disponíveis sobre os limites seguros da resposta pressórica aguda nessa modalidade. OBJETIVO: Investigar o efeito agudo do exercício resistido progressivo, de diferentes segmentos corporais, na resposta pressórica de pacientes com hipertensão arterial sistêmica (HAS) controlada. MÉTODOS: Vinte e cinco pacientes (14 mulheres) com HAS controlada com medicamentos (64,5 ± 10,8 anos de idade) e sedentários, realizaram três visitas para uma sessão de exercício resistido progressivo aleatória, nos seguintes grupos musculares: quadríceps femoral, grande dorsal e bíceps braquial. Medidas de pressão arterial foram obtidas em todas as visitas no repouso, imediatamente após cada série de exercício e após 5 minutos de recuperação. RESULTADOS: Imediatamente após o exercício resistido agudo, houve significante aumento das pressões sistólicas, sem modificações significantes das pressões diastólicas, quando comparadas aos níveis pressóricos de repouso, para todos os grupos musculares e para todas as intensidades avaliadas. Adicionalmente, observou-se maior tendência à elevação da pressão sistólica quando o quadríceps femoral foi exercitado em alta intensidade. CONCLUSÃO: O exercício resistido de diferentes segmentos corporais promoveu aumentos similares e seguros dos níveis de pressão arterial sistólica, embora com tendência a maior resposta desta quando exercitados grandes grupos musculares em cargas elevadas.

Efeitos da exposição à fumaça lateral do cigarro sobre o barorreflexo em ratos adultos

FUNDAMENTO: Tem sido demonstrado na literatura que a exposição à fumaça do cigarro causa hipertensão em ratos; entretanto, ainda não foi demonstrado se a função barorreflexa está prejudicada antes do animal se tornar hipertenso. OBJETIVO: Avaliamos os efeitos de curto prazo da exposição à fumaça lateral do cigarro (FLC) sobre a função barorreflexa em ratos Wistar normotensos. MÉTODOS: Os ratos foram expostos à FLC durante três semanas, 180 minutos, cinco dias por semana, a uma concentração de monóxido de carbono entre 100-300 ppm. A pressão arterial média (PAM) e a freqüência cardíaca (FC) foram avaliadas através de canulação da veia e artéria femoral. RESULTADOS: Não houve diferença significante entre os grupos controle e FLC em relação à MAP e FC, componentes simpáticos e parassimpáticos da função barorreflexa. CONCLUSÃO: Nossos dados sugerem que três semanas de exposição à FLC não são suficientes para causar dano significante aos parâmetros cardiovasculares e sensibilidade barorreflexa em ratos Wistar normotensos.

Acesso radial em intervenções coronarianas percutâneas: panorama atual brasileiro

FUNDAMENTO: Embora a técnica radial exiba resultados incontestáveis na redução de complicações vasculares e ocorrência de sangramento grave quando comparada à técnica femoral, seu emprego permanece restrito a poucos centros que a elegeram como via de acesso preferencial. OBJETIVO: Avaliar o cenário atual das intervenções coronarianas percutâneas no Brasil quanto à utilização da via de acesso radial. MÉTODOS: Análise dos dados cadastrados de forma espontânea na Central Nacional de Intervenções Cardiovasculares (CENIC) durante o quadriênio de 2005-2008, o que totaliza 83.376 procedimentos. RESULTADOS: A técnica radial foi utilizada em 12,6% dos procedimentos efetivados, e a técnica femoral, em 84,3%. Os 3,1% restantes foram representados pela dissecção ou punção braquial. Com uma taxa de sucesso de 97,5%, a opção pelo acesso radial associou-se à redução significativa de complicações vasculares quando comparado ao femoral (2,5% versus 3,6%, p < 0,0001). CONCLUSÃO: A utilização da técnica radial permanece baixa no Brasil. Ausência de programas de treinamento, incertezas quanto à curva de aprendizagem e carência de estudos em larga escala, que corroboram os benefícios demonstrados até o momento, são possíveis justificativas para esses achados.

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

Background: Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients. Objective: To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations. Methods: This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years) with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior® device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound. Results: The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01) and triglycerides (p = 0.02); intima-media thickness, to age (p < 0.01); diameter, to creatinine (p = 0.03) and age (p = 0.02); relative distensibility, to age (p < 0.01) and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively). Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01) and with relative distensibility (p < 0.01), while diameter showed a positive correlation with distensibility (p = 0.03). Conclusion: In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic blood pressure related to the carotid functional measure. The carotid artery structure was directly related to aortic stiffness, which was inversely related to the carotid artery functional property.

Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

Background:Heart failure and atrial fibrillation (AF) often coexist in a deleterious cycle.Objective:To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF) ablation.Methods:Patients with ventricular systolic dysfunction [ejection fraction (EF) <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class) and echocardiographic (EF, left atrial diameter) data were compared (McNemar test and t test) before and after ablation.Results:31 patients (6 women, 25 men), aged 37 to 77 years (mean, 59.8±10.6), underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%). During a mean follow-up of 20.3±17 months, 24 patients (77%) were in sinus rhythm, 11 (35%) being on amiodarone. Eight patients (26%) underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures). Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001). The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005) and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026). No major complications occurred.Conclusion:Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement.

Role of microRNAs 221/222 on Statin Induced Nitric Oxide Release in Human Endothelial Cells

Background: Nitric oxide (NO) has been largely associated with cardiovascular protection through improvement of endothelial function. Recently, new evidence about modulation of NO release by microRNAs (miRs) has been reported, which could be involved with statin-dependent pleiotropic effects, including anti-inflammatory properties related to vascular endothelium function. Objective: To evaluate the effects of cholesterol-lowering drugs including the inhibitors of cholesterol synthesis, atorvastatin and simvastatin, and the inhibitor of cholesterol absorption ezetimibe on NO release, NOS3 mRNA expression and miRs potentially involved in NO bioavailability. Methods: Human umbilical vein endothelial cells (HUVEC) were exposed to atorvastatin, simvastatin or ezetimibe (0 to 5.0 μM). Cells were submitted to total RNA extraction and relative quantification of NOS3 mRNA and miRs -221, -222 and -1303 by qPCR. NO release was measured in supernatants by ozone-chemiluminescence. Results: Both statins increased NO levels and NOS3 mRNA expression but no influence was observed for ezetimibe treatment. Atorvastatin, simvastatin and ezetimibe down-regulated the expression of miR-221, whereas miR-222 was reduced only after the atorvastatin treatment. The magnitude of the reduction of miR-221 and miR-222 after treatment with statins correlated with the increment in NOS3 mRNA levels. No influence was observed on the miR-1303 expression after treatments. Conclusion: NO release in endothelial cells is increased by statins but not by the inhibitor of cholesterol absorption, ezetimibe. Our results provide new evidence about the participation of regulatory miRs 221/222 on NO release induction mediated by statins. Although ezetimibe did not modulate NO levels, the down-regulation of miR-221 could involve potential effects on endothelial function.

Comparison of ACUITY and CRUSADE Scores in Predicting Major Bleeding during Acute Coronary Syndrome

Background:The ACUITY and CRUSADE scores are validated models for prediction of major bleeding events in acute coronary syndrome (ACS). However, the comparative performances of these scores are not known.Objective:To compare the accuracy of ACUITY and CRUSADE in predicting major bleeding events during ACS.Methods:This study included 519 patients consecutively admitted for unstable angina, non-ST-elevation or ST-elevation myocardial infarction. The scores were calculated based on admission data. We considered major bleeding events during hospitalization and not related to cardiac surgery, according to the Bleeding Academic Research Consortium (BARC) criteria (type 3 or 5: hemodynamic instability, need for transfusion, drop in hemoglobin ≥ 3 g, and intracranial, intraocular or fatal bleeding).Results:Major bleeding was observed in 31 patients (23 caused by femoral puncture, 5 digestive, 3 in other sites), an incidence of 6%. While both scores were associated with bleeding, ACUITY demonstrated better C-statistics (0.73, 95% CI = 0.63 - 0.82) as compared with CRUSADE (0.62, 95% CI = 0.53 - 0.71; p = 0.04). The best performance of ACUITY was also reflected by a net reclassification improvement of + 0.19 (p = 0.02) over CRUSADE’s definition of low or high risk. Exploratory analysis suggested that the presence of the variables ‘age’ and ‘type of ACS’ in ACUITY was the main reason for its superiority.Conclusion:The ACUITY Score is a better predictor of major bleeding when compared with the CRUSADE Score in patients hospitalized for ACS.

Tramadol Alleviates Myocardial Injury Induced by Acute Hindlimb Ischemia Reperfusion in Rats

AbstractBackground:Organ injury occurs not only during periods of ischemia but also during reperfusion. It is known that ischemia reperfusion (IR) causes both remote organ and local injuries.Objective:This study evaluated the effects of tramadol on the heart as a remote organ after acute hindlimb IR.Methods:Thirty healthy mature male Wistar rats were allocated randomly into three groups: Group I (sham), Group II (IR), and Group III (IR + tramadol). Ischemia was induced in anesthetized rats by left femoral artery clamping for 3 h, followed by 3 h of reperfusion. Tramadol (20 mg/kg, intravenous) was administered immediately prior to reperfusion. At the end of the reperfusion, animals were euthanized, and hearts were harvested for histological and biochemical examination.Results:The levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were higher in Groups I and III than those in Group II (p < 0.05). In comparison with other groups, tissue malondialdehyde (MDA) levels in Group II were significantly increased (p < 0.05), and this increase was prevented by tramadol. Histopathological changes, including microscopic bleeding, edema, neutrophil infiltration, and necrosis, were scored. The total injuryscore in Group III was significantly decreased (p < 0.05) compared with Group II.Conclusion:From the histological and biochemical perspectives, treatment with tramadol alleviated the myocardial injuries induced by skeletal muscle IR in this experimental model.

Observações sôbre a anestesia geral pelo hidrato de cloral na prática da cirurgia veterinária

In this paper the A. A. report the observations about the general anesthesia by chloral hydrate on the veterinary surgery. The observations were made on emasculation practices of horses, mules and hogs. It was possible to establish the following conclusions: 1) The choral hydrate presents low cost, it harmless, and is of easy application. 2) The more recommendable dosis for equine and swine were : 12-13 g per 100 k of body weight, in destilled water solution at 30 and 20%, respectively. 3) The anaethestic was injected by intravenous way with good results; in horses and mules the applications were made in the jugular; in swine, in the anterior vena cava, as was described by Carle and Dewhirst, because it was impracticable in the ear vein. 4) The dosis applied produced deep narcosis not lasting to long and with no danger to the animal's life. 5) In the case of fattening hogs, it must be made a discount of about 40% on the body weight, to calculate dosis to be employed. 6) The tables A and B show the results, that may be considered as good.

Histology of the liver of Oligosarcus jenynsii (Ostariophysi, Characidae) from Los Padres Lake, Argentina

The liver is an organ notable for its sensitivity to a great variety of environmental factors. It is composed of a parenchyma divided into irregular lobules by the exocrine pancreas or hepatopancreas; the pancreatic cells are arranged around a branch of the portal vein. The hepatocytes are radially arranged in cords around a central sinusoid. The liver histomorphology and the organization of exocrine pancreatic tissue of O. jenynsii (Günther, 1864) is similar to the acinar morphology of many teleosts, including freshwater and marine species. The aim of the present work was to carry out the histological analysis of the liver of Oligosarcus jenynsii, one of the most common species inhabiting Los Padres Lake (Buenos Aires Province, Argentina).

Contribuição para o conhecimento da intoxicação pelo veneno dos "escorpiões"

Nous avons travaillé à Bello Horizonte, Etat de Minas, avec le venin de 4 espèces de Scorpions: Tityus bahiensis (C. L. KOCK, 1836). Tityus serrulatus (LUTZ-MELLO, 1922). Tityus dorsomaculatus (LUTZ – MELLO, 1922). Bothriurus (espèce em étude), sur un total de 13.640 individus. Nous avons essayé et observe l’action du venin sur 97 espèces differentes d’êtres vivants – depuis les chlamydozoaires jusqu’à l’«Homo sapiens». Nous avons cherché à déterminer une unité toxique «plus précise, plus régulierè». Les étalons dits «unité vésicule», «unité morsure» sont inconstants et sans rigueur. Tout au plus, peuvent ils server à l’étude de l’action générale du venin, et cela meme, dans certains cas seulement. Nous avons employé la pesée pour determiner l’unité toxique. Ce qui est important pour qui étudie ces sujets ce n’est pás lê nombre de vésicules, mais bien la quantité de venin humide ou desséché qu’elles contiennent. La balance, pour notre travail, est um moyen indicateur de bien plus grande précision que la «vésicule» ou la «morsure». Nous sommes parvenus à prouver qu’il existe une relation constante entre le poid brut des vésicules et la quantité de venin humide ou desséché qu’elles contiennent dans leur intérieur. Donc em pesant les vésicules, nous pesons indirectement le venin. Peu nous importe qu’il y ait 10 ou 100 vésicules. Il nous importe seulement de savoir combien elles pèsent, et de déterminer par ce fait, la quantité proportionnelle de vain pur. La technique générale est la suivante: Nous pesons um certain nombre de vésicules. Nous triturons ensuite, dans um mortier stérilisé et nous emulsionnons, par l’addition consécutive d’eau distillée, stérilisée. Nous filtrons l’émulsion sur le papier filtre employé em chimie, préalablement taré et desséché dans une atmosphere de chlorure de calcium. Après le filtrage on sèche à nouveau les papiers filtre employés d'abord à l'étuve et ensuite dans la même atmosphère de chlorure de calcium. Nous pesons plusieurs fois et on obtient la moyenne de ces pesées. On soustrait de cette dernière pesée le taux des substances non venimeuses, glandulaires, également dissoutes et calculées à 23 du poids brut et celles retenues par les papiers,-on obtient ainsi la moyenne réelle du venin pur contenu dans les vésicules utilisèés. Une simple divisiôn suffit pour fixer la moyenne de chacune. Ces données ont été vérifiées par les expériences faites avec du venin pur, largement obtenu dans notre Laboratoire. Nous avons trouvé de la sorte pour une vésicule de Tityus serrulatus: 0,gr.000,386 de T. bahiensis: 0,gr.001.261.24 de venin pur ce qui donne. 7/15,96 pour la 1ère. 1/8,36 pour la 2ème du poids sec de chaque vésicule. Le poids sec, pour une moyenne obtenue de 1.000 vésicules, fut de 0,gr.008,236 pour Tityus bahiensis. Maximum 0,gr.011. Minimum 0,gr.004.4 pour chacun. Pour Tityus serrulatus, en 1.049 vésicules le poids fut de 0,gr.006,08. Maximum 0,gr.014.03. Minimum 0,gr.003,1 pour chacun. C'est pour cette raison que l'unité-vésicule est incertaine. 2 poules A et B.; l'une, A, pesant 2 K.030 gr. reçoit dans une veinè, une émulsion en sèrum physiologique à 8,50/%, stérilisé, de 19 vésicules totales de Tityus serrulatus, et présence de légers phénomènes toxiques. L'autre, B, pesant 2 K.320 gr. meurt avec tous les phénomènes classiques de l'empoisonnement, par l'injection endoveineuse del'émulsion de 16 vésicules totales de venin de Tityus serrulatus! Les premières 19 vésicules pesaient 0,gr.58; les 16 derniéres-84 milligrammes. Les premières contenaient 0,gr.003. 634 et les secondes 0,gr.005.263 de venin pur! La moyenne obtenue de 6346 scorpions, (entre T. bahiensis et T. serrulatus) nous a fourni pour chacun: 0,gr.000,131,53 de venin pur, par piqûre. Si l'on spécifie: Pour 5.197 T. bahiensis. La moyenne pour une piqûre est 0,gr.000.106.15. Pour 1.149 T. serrulatus, la moyenne pour une piqûre est.......0,gr.000.246.30. La quantité a varié, selon les individus, de 0,gr.000.035.71, à 0,gr.000.436.01 de venin pur, pour une piqûre. D'après ce qui vient d'étre dit, on peut voir combien la quantité de venin éjaculé varie, chaque fois, chez les scorpions. L'unité-piqûre ne peut done pas ètre utiliseé pour des expériences dèlicates. Le mieux est de se servir de venin pur, et c'est ce que nous avons fait pour les expériences minutieuses. Quand on n'en possède pas, on peut établir pour chaque série des expériences à tenter-la dose minima mortelle en poids (grammes et fractions) de vésicules. D'après les bases ici consignées, et avec une trés petite erreur, on peut calculer la quantité de venin pur de cette dóse. Ce calcul est d'ailleurs dispensable. On peut s'en rapporter simplement au poids sec des vésicules totales et dire que la D. m. m. est de tant de milligr. secs. Comme le venin se conserve mal dans les vésicules, il faut, dans ce procédé, doser la D. m. m. toutes les fois que l'on veut procéder á une sériê d'expériences. Le venin desséché rappelle, d'après le temps de conservations au Laboratoire, celui de Crotatus terrificus et celui des Lachesis (quand il est vieux). Il est retenu au passage en partie, par les bougies Berkfeld et Chamberland. La conservation en état de dessication est la meilleure. Ainsi gardé, à l'abri de la lumierè, aux approches de 0,gr., pendant 8 mois, il perd à peine 1,2 à 1,4 de sa valeur primitive. L'echauffement à 100 gr. trouble une dissolution de venin dans l'eau distilleé; sans atteindre toutefois son pouvoir toxique, quand on l'injecte par la voie intra-cérébrale. Nous avons fait l'experience par 11 voies diverses. Sur des animaux sensibles, nous n'avons pas obtenu de phénomènes toxiques, apparemment, par les voies suivantes: 1) buccale; 2) gastrique; 3) rectale; 4) chambre oculaire antérieure; 5) cornéenne; 6) trachéenne; 7) meningée {sur; intra; 8) simple contact, bien que direct, avec le systemè nerveux central. La gravité des phènomènes décroît suivant l'échelle ci-dessous: 1) intra-cérébrale...

Ganglioneuroma da região cervical

A case of ganglioneuroma in the neck of a girl sixteen years old first noticed at the age of fifteen months is reported. The tumor successfully removed at operation has the size of an orange and is in relation by its internal surface with the trachea, oesophagus and vertebral column. Anteriorly it is crossed by the left common carotid and internal jugular vein which are meanwhile dissociated. Although this suggests an origin from the pneumogastric nerve no convincing proof of such an origin was obtained.