Grafting of Araucaria angustifolia (BERTOL.) kuntze through the four seasons of the year

Araucaria angustifolia is an endangered conifer species of South America that has been over exploited for timber. To incentivize Araucaria angustifolia planting is essential and may play a key role on the conservation of this species and the ecosystems that depend on it. Hence, techniques that allow the production of seedlings with attributes that may entice farmers to plant A. angustifolia trees are very important. Grafting may permit the selection of female trees and the production of precocious plants that will produce high quality seeds. The aim of this study was to determine the best season of the year to graft. Three-year-old seedlings were used as rootstock and orthotropic branches of young plants were used for scion collection. The technique used for the grafting was the bark patch. This procedure was carried out in the beginning of each season in 2007 and 2008, with a total of 160 grafted plants. Grafting carried out in the beginning of autumn had a 50 % success rate. Grafting success was negligible for all remaining seasons. In conclusion, grafting through bark patching is a viable technique for the production of A. angustifolia seedlings. Future research should be carried out to produce grafted seedlings in large-scale.

Breeding, genetic and genomic of citrus for disease resistance

Although the citriculture is one of the most important economic activities in Brazil, it is based on a small number of varieties. This fact has contributed for the vulnerability of the culture regarding the phytosanitary problems. A higher number of varieties/genotypes with potential for commercial growing, either for the industry or fresh market, has been one of the main objectives of citrus breeding programs. The genetic breeding of citrus has improved, in the last decades, due to the possibility of an association between biotechnological tools and classical methods of breeding. The use of molecular markers for early selection of zygotic seedlings from controlled crosses resulted in the possibility of selection of a high number of new combination and, as a consequence, the establishment of a great number of hybrids in field experiments. The faster new tools are incorporated in the program, the faster is possibility to reach new genotypes that can be tested as a new variety. Good traits should be kept or incorporate, whereas bad traits have to be excluded or minimized in the new genotype. Scion and rootstock can not be considered separately, and graft compatibility, fruit quality and productivity are essential traits to be evaluated in the last stages of the program. The mapping of QTLs has favored breeding programs of several perennial species and in citrus it was possible to map several characteristics with qualitative and quantitative inheritance. The existence of linkage maps and QTLs already mapped, the development of EST and BAC library and the sequencing of the Citrus complete genome altogether make very demanding and urgent the exploration of such data to launch a wider genetic study of citrus. The rising of information on genome of several organisms has opened new approaches looking for integration between breeding, genetic and genome. Genome assisted selection (GAS) involves more than gene or complete genome sequencing and is becoming an import support in breeding programs of annual and perennial species. An huge information amount can be derivate from genome analysis. The use and benefit of such informations will depend on the genetic basis of the breeding program.

Analysis of flow dynamics in right ventricular outflow tract.

BACKGROUND: The mechanism behind early graft failure after right ventricular outflow tract (RVOT) reconstruction is not fully understood. Our aim was to establish a three-dimensional computational fluid dynamics (CFD) model of RVOT to investigate the hemodynamic conditions that may trigger the development of intimal hyperplasia and arteriosclerosis. METHODS: Pressure, flow, and diameter at the RVOT, pulmonary artery (PA), bifurcation of the PA, and left and right PAs were measured in 10 normal pigs with a mean weight of 24.8 ± 0.78 kg. Data obtained from the experimental scenario were used for CFD simulation of pressure, flow, and shear stress profile from the RVOT to the left and right PAs. RESULTS: Using experimental data, a CFD model was obtained for 2.0 and 2.5-L/min pulsatile inflow profiles. In both velocity profiles, time and space averaged in the low-shear stress profile range from 0-6.0 Pa at the pulmonary trunk, its bifurcation, and at the openings of both PAs. These low-shear stress areas were accompanied to high-pressure regions 14.0-20.0 mm Hg (1866.2-2666 Pa). Flow analysis revealed a turbulent flow at the PA bifurcation and ostia of both PAs. CONCLUSIONS: Identified local low-shear stress, high pressure, and turbulent flow correspond to a well-defined trigger pattern for the development of intimal hyperplasia and arteriosclerosis. As such, this real-time three-dimensional CFD model may in the future serve as a tool for the planning of RVOT reconstruction, its analysis, and prediction of outcome.

Transition en transplantation rénale [Transition in kidney transplantation].

La transition en transplantation rénale constitue une étape importante dans la vie d'un jeune adolescent greffé. Durant cette période, les impératifs de la greffe se heurtent aux changements physiologiques et psychologiques de l'adolescence, avec un risque augmenté de non-observance thérapeutique et donc de perte du greffon. Il n'existe pas encore un modèle optimal de transition unanimement accepté, mais il a été démontré que la mise en place d'une équipe multidisciplinaire de professionnels pédiatres et adultes, ayant une formation dans la gestion des adolescents et jeunes adultes, est bénéfique. Cette équipe doit assurer une transition progressive des jeunes patients vers la clinique adulte selon un plan bien défini. Transition from pediatric to adult care in renal transplantation has emerged as a critical step in the life of a young kidney recipient. During this phase, young patients are faced with the physiological and psychological changes associated with adolescence that can lead to non-compliance and potentially graft loss. To date, there is not a unique accepted model of transition, however it has been proved that the presence of a multidisciplinary team including specialists in adolescent management and in the transition from pediatric to adult transplant care is beneficial during this at-risk phase. The goal of this team is to ensure a progressive transition of the patients according to a precise plan and time line.

Novel therapeutic strategies targeting regulatory T cells and downstream TCR signaling in transplantation

Avec plus de 100000 transplantations d'organes solides (TOS) par année dans le monde, la transplantation d'organes reste actuellement l'un des meilleurs traitements disponibles pour de nombreuses maladies en phase terminale. Bien que les médicaments immunosuppresseurs couramment utilisés soient efficaces dans le contrôle de la réponse immune engendrant le rejet aigu d'une greffe, la survie du greffon à long terme ainsi que la présence d'effets secondaires indésirables restent un enjeu considérable en clinique. C'est pourquoi il est nécessaire de trouver de nouvelles approches thérapeutiques innovantes permettant de contrôler la réponse immunitaire et ainsi d'améliorer les résultats à long terme. L'utilisation des lymphocytes T régulateurs (Treg), suppresseurs naturels de la réponse inflammatoire, a fait l'objet de nombreuses études ces dix dernières années, et pourrait être considérée comme un moyen intéressant d'améliorer la tolérance immunologique de la greffe. Cependant, l'un des obstacles de l'utilisation des Treg comme agent thérapeutique est leur nombre insuffisant non seulement en conditions normales, mais en particulier lors d'une forte réponse immune avec expansion de cellules immunitaires alloréactives. En raison des limitations techniques connues pour l'induction des Treg ex-vivo ou in vitro, nous avons dédié la première partie du travail de thèse à la détermination de l'efficacité de l'induction des Treg in vivo grâce à l'utilisation d'un complexe protéique IL-2/JES6-1 (IL2c). Nous avons montré que l'expansion des Treg par IL2c permettait d'augmenter la survie du greffon sur un modèle murin de transplantation de peau avec mismatch entre le donneur et le receveur pour le complexe majeur d'histocompatibilité (CMH). De plus, nous avons vu qu'en combinant IL2c à une inhibition à court terme de la voie de co-stimulation CD40L-CD40 (anti-CD154/MRl, administré au moment de la transplantation) pour empêcher l'activation des lymphocytes T, il est possible d'induire une tolérance robuste à long terme. Finalement, nos résultats soulignent l'importance de cibler une voie de co-stimulation bien particulière. En effet, l'utilisation d'IL2c combinée au blocage de la co-stimulation CD28-B7.1/2 (CTLA-4 Ig) n'induit qu'une faible prolongation de la survie de la greffe et n'induit pas de tolérance. L'application chez l'humain des traitements induisant la tolérance dans des modèles expérimentaux murins ou de primates n'a malheureusement pas montré de résultats probants en recherche clinique ; une des principales raisons étant la présence de lymphocytes B et T mémoires provenant du systeme d immunité acquise. C est pourquoi nous avons testé si la combinaison d'IL2c et MR1 améliorait la survie de la greffe dans des souris pré¬sensibilisées. Nous avons trouvé qu'en présence de lymphocytes B et T mémoires alloréactifs, l'utilisation d'IL2c et MR1 permettait une amélioration de la survie de la greffe de peau des souris immunocompétentes mais comparé aux souris receveuses naïves, aucune tolérance n'a pu être induite. Toutefois, l'ajout d'un traitement anti-LFA-1 (permettant de bloquer la circulation des lymphocytes T activées) a permis d'améliorer de manière significative la survie de la greffe. Cependant, le rejet chronique, dû à la présence de lymphocytes B activés/mémoires et la production d'anticorps donneur-spécifiques, n'a pas pu être évité. Cibler l'activation des lymphocytes T est la stratégie immunothérapeutique prépondérente après une TOS. C'est pourquoi dans la deuxième partie de cette thèse nous nous sommes intéressés au système de signalisation d'un récepteur des lymphocytes T qui dépend de la paracaspase Malti en tant que nouvelle stratégie immunosuppressive pour le contrôle des lymphocytes T alloréactifs. Nous avons montré que bien que l'inhibition de la signalisation du lymphocyte T en aval de Malti induise une tolérance envers un greffon de peau avec incompatibilités antigéniques mineures, cela ne permet cependant qu'une régulation partielle de l'alloréponse contre des antigènes du CMH. Nous nous sommes aussi intéressés spécifiquement à l'activité protéolytique de Malti. L'inhibition constitutive de l'activité protéolytique de Malti chez les souris Malti-ki s'est révélée délétère pour l'induction de la tolérance car elle diminue la fonction des Treg et augmente l'alloréactivité des cellules Thl. Cependant, lors de l'utilisation d'un inhibiteur peptidique de l'activité protéase de Malti in vitro, il a été possible d'observer une atténuation de l'alloéactivité des lymphocytes T ainsi qu'un maintien de la population des Treg existants. Ces résultats nous laissent penser que des études plus poussées sur le rôle de la signalisation médiée par Malti seraient à envisager dans le domaine de la transplantation. En résumé, les résultats obtenus durant cette thèse nous ont permis d'élucider certains mécanismes immunologiques propres à de nouvelles stratégies thérapeutiques potentielles dont le but est d'induire une tolérance lors de TOS. De plus, ces résultats nous ont permis de souligner l'importance d'utiliser des modèles davantage physiologiques contenant, notamment en tenant compte des lymphocytes B et T mémoires alloréactifs. -- Organ transplantation remains the best available treatment for many forms of end-stage organ diseases, with over 100,000 solid organ transplantations (SOT) occurring worldwide eveiy year. Although the available immunosuppressive (IS) drugs are efficient in controlling acute immune activation and graft rejection, the off-target side effects as well as long-term graft and patient survival remain a challenge in the clinic. Hence, innovative therapeutic approaches are needed to improve long-term outcome across immunological barriers. Based on extensive experimental data obtained over the last decade, it is tempting to consider immunotherapy using Treg; the natural suppressors of overt inflammatory responses, in promoting transplantation tolerance. The first hurdle for the therapeutic use of Treg is their insufficient numbers in non- manipulated individuals, in particular when facing strong immune activation and expanding alloreactive effector cells. Because of the limitations associated with current protocols aiming at ex-vivo expansion or in vitro induction of Treg, the aim of the first part of this thesis was to determine the efficacy of direct in vivo expansion of Treg using the IL-2/JES6- 1 immune complex (IL2c). We found that whilst IL2c mediated Treg expansion alone allowed the prolonged graft survival of fìlli MHC-mismatched skin grafts, its combination with short-term CD40L-CD40 co-stimulation blockade (anti-CD 154/MR1) to inhibit T cell activation administered at the time of transplantation was able to achieve long-term robust tolerance. This study also highlighted the importance of combining Treg based therapies with the appropriate co-stimulation blockade as a combination of IL2c and CD28-B7.1/2 co- stimulation blockade (CTLA-4 Ig) only resulted in slight prolongation of graft survival but not tolerance. The translation of tolerance induction therapies modelled in rodents into non-human primates or into clinical trials has seldom been successful. One main reason being the presence of pre-existing memory T- and B-cells due to acquired immunity in humans versus laboratory animals. Hence, we tested whether IL2c+MRl could promote graft survival in pre-sensitized mice. We found that in the presence of alloreactive memory T- and B-cells, IL2c+MRl combination therapy could prolong MHC-mismatched skin graft survival in immunocompetent mice but tolerance was lost compared to the naïve recipients. The addition of anti-LF A-1 treatment, which prevents the trafficking of memory T cells worked synergistically to significantly further enhance graft survival. However, late rejection mediated by activated/memory B cells and persistent donor-specific alloantibodies still occurred. Immunotherapeutic strategies targeting the activation of T cells are the cornerstone in the current immunosuppressive management after SOT. Therefore, in the next part of this thesis we investigated the paracaspase Malti-dependent T-cell receptor signalling as a novel immunosuppressive strategy to control alloreactive T cells in transplantation. We observed that although the inhibition of Malti downstream T signalling lead to tolerance of a minor H- mismatch skin grafts, it was however not sufficient to regulate alloresponses against MHC mismatches and only prolonged graft survival. Furthermore, we investigated the potential of more selectively targeting the protease activity of Malti. Constitutive inhibition of Malti protease activity in Malti-ki mice was detrimental to tolerance induction as it diminished Treg function and increased Thl alloreactivity. However, when using a small peptide inhibitor of Malti proteolytic activity in vitro, we observed an attenuation of alloreactive T cells and sparing of the pre-existing Treg pool. This indicates that further investigation of the role of Malti signalling in the field of transplantation is required. Collectively, the findings of this thesis provide immunological mechanisms underlying novel therapeutic strategies for the promotion of tolerance in SOT. Moreover, we highlight the importance of testing tolerance induction therapies in more physiological models with pre-existing alloreactive memory T and B cells.

Aorto-bronchial and aorto-pulmonary fistulation after thoracic endovascular aortic repair: an analysis from the European Registry of Endovascular Aortic Repair Complications.

OBJECTIVES: To learn upon incidence, underlying mechanisms and effectiveness of treatment strategies in patients with central airway and pulmonary parenchymal aorto-bronchial fistulation after thoracic endovascular aortic repair (TEVAR). METHODS: Analysis of an international multicentre registry (European Registry of Endovascular Aortic Repair Complications) between 2001 and 2012 with a total caseload of 4680 TEVAR procedures (14 centres). RESULTS: Twenty-six patients with a median age of 70 years (interquartile range: 60-77) (35% female) were identified. The incidence of either central airway (aorto-bronchial) or pulmonary parenchymal (aorto-pulmonary) fistulation (ABPF) in the entire cohort after TEVAR in the study period was 0.56% (central airway 58%, peripheral parenchymal 42%). Atherosclerotic aneurysm formation was the leading indication for TEVAR in 15 patients (58%). The incidence of primary endoleaks after initial TEVAR was n = 10 (38%), of these 80% were either type I or type III endoleaks. Fourteen patients (54%) developed central left bronchial tree lesions, 11 patients (42%) pulmonary parenchymal lesions and 1 patient (4%) developed a tracheal lesion. The recognized mechanism of ABPF was external compression of the bronchial tree in 13 patients (50%), the majority being due to endoleak formation, further ischaemia due to extensive coverage of bronchial feeding arteries in 3 patients (12%). Inflammation and graft erosion accounted for 4 patients (30%) each. Cumulative survival during the entire study period was 39%. Among deaths, 71% were attributed to ABPF. There was no difference in survival in patients having either central airway or pulmonary parenchymal ABPF (33 vs 45%, log-rank P = 0.55). Survival with a radical surgical approach was significantly better when compared with any other treatment strategy in terms of overall survival (63 vs 32% and 63 vs 21% at 1 and 2 years, respectively), as well as in terms of fistula-related survival (63 vs 43% and 63 vs 43% at 1 and 2 years, respectively). CONCLUSIONS: ABPF is a rare but highly lethal complication after TEVAR. The leading mechanism behind ABPF seems to be a continuing external compression of either the bronchial tree or left upper lobe parenchyma. In this setting, persisting or newly developing endoleak formation seems to play a crucial role. Prognosis does not differ in patients with central airway or pulmonary parenchymal fistulation. Radical bronchial or pulmonary parenchymal repair in combination with stent graft removal and aortic reconstruction seems to be the most durable treatment strategy.

Fluid dynamics simulation of right ventricular outflow tract oversizing.

OBJECTIVES: Repair of the right ventricular outflow tract (RVOT) in paediatric cardiac surgery remains challenging due to the high reoperation rate. Intimal hyperplasia and consequent arteriosclerosis is one of the most important limitation factors for graft durability. Since local shear stress and pressure are predictive elements for intimal hyperplasia and wall degeneration, we sought to determine in an oversized 12-mm RVOT model, with computed fluid dynamics simulation, the local haemodynamical factors that may explain intimal hyperplasia. This was done with the aim of identifying the optimal degree of oversizing for a 12-mm native RVOT. METHODS: Twenty domestic pigs, with a weight of 24.6 ± 0.89 kg and a native RVOT diameter of 12 ± 1.7 mm, had valve conduits of 12, 16, 18 and 20 mm implanted. Pressure and flow were measured at 75, 100 and 125% of normal flow at RVOT at the pulmonary artery, pulmonary artery bifurcation and at the left and right pulmonary arteries. Three-dimensional computed fluid dynamics (CFD) simulation in all four geometries in all flow modalities was performed. Local shear stress and pressure conditions were investigated. RESULTS: Corresponding to 75, 100 and 125% of steady-state flow, three inlet velocity profiles were obtained, 0.2, 0.29 and 0.36 m/s, respectively. At inflow velocity profiles, low shear stress areas, ranged from 0 to 2 Pa, combined with high-pressure areas ranging from 11.5 to 12.1 mmHg that were found at distal anastomosis, at bifurcation and at the ostia of the left and right pulmonary arteries in all geometries. CONCLUSIONS: In all three oversized geometries, the local reparation of shear stress and pressure in the 16-mm model showed a similar local profile as in the native 12 mm RVOT. According to these findings, we suggest oversizing the natural 12-mm RVOT by not more than 4 mm. The elements responsible for wall degeneration and intimal hyperplasia remain very similar to the conditions present in native RVOT.

A descriptive study on the surgery and the microbiology of Gustilo type III fractures in an university hospital in Switzerland.

OBJECTIVE: To describe the epidemiology, the surgical treatment, the microbiology, the antibiotic prophylaxis and the outcome of patients with the most severe type of open fractures. METHODS: Retrospective chart reviews of patients with Gustilo type III open fracture admitted to an university hospital in Switzerland between January 2007 and December 2011. The patient's and fracture's characteristics, surgery, antibiotic prophylaxis, and microbiology findings at the initial and at the revision surgery were described. RESULTS: Thirty patients were included (83% male, mean age 41 years). More than half of the patients had polytrauma. In all patients, debridement and stabilization surgery (70% using external fixation) were performed at admission. Soft tissue reconstruction was performed in 87% and in 23% immediate bone graft was performed. Antibiotic prophylaxis were given in all patients for a median duration of 9 days (60% received amoxicillin/clavulanic acid). Positive bacterial culture was found in 53% of the patients at initial surgery and in 88% at revision surgery. At initial and revision surgery, 47% and 88% of the pathogens were amoxicillin/clavulanic acid-resistant. Treatment outcome was favorable in 24 of 30 patients (80%) and in six cases (20%) an amputation had to be performed. None of the patients had chronic bone infection. CONCLUSIONS: Positive cultures were found often in open fractures. Amoxicillin/clavulanic acid which is often mentioned in many guidelines as prophylaxis in open fractures does not cover the most common isolated organisms. The combination of surgery and antibiotic prophylaxis leads to good outcome in Gustilo type III fracture.

The Combined Pedicled Anterolateral Thigh and Vastus Lateralis Flap as Filler for Complex Perineal Defects.

Extensive defects of the pelvis and genitoperineal region are a reconstructive challenge. We discuss a consecutive series of 25 reconstructions with the pedicled anterolateral thigh (ALT) flap including muscle part of the vastus lateralis (VL) in 23 patients from October 1999 to September 2012.Only surface defects larger than 100 cm and reconstructions by composite ALT + VL were included in this retrospective analysis. Of the 23 patients, 19 underwent oncologic resection, whereas 4 cases presented Fournier gangrene. Three patients did not reach 6 months of follow-up and were excluded from further data analysis. Among the remaining 20 patients (22 reconstructions), average follow-up period was 14 months (range, 10-18 months). Patient's average age was 60 years. Average size of the defect was 182 cm.Postoperative complications included 1 (4.5%) flap necrosis out of 22 raised flaps, 1 partial flap necrosis after venous congestion, and 2 cases where a complementary reconstructive procedure was performed due to remaining defect or partial flap failure. In 6 cases, peripheral wound dehiscence (27%) was treated by debridement followed by split-thickness skin graft or advancement local flaps. Defect size was significantly related to postoperative complications and increased hospital stay, especially in those patients who underwent preoperative radiotherapy. At the end of the follow-up period, a long-term and satisfactory coverage was obtained in all patients without functional deficits.This consecutive series of composite ALT + VL flap shows that, in case of extended defects, the flap provides an excellent and adjustable muscle mass, is reliable with minimal donor-site morbidity, and can even be designed as a sensate flap.

A new formula for calculating standard liver volume for living donor liver transplantation without using body weight.

BACKGROUND & AIMS: The standard liver volume (SLV) is widely used in liver surgery, especially for living donor liver transplantation (LDLT). All the reported formulas for SLV use body surface area or body weight, which can be influenced strongly by the general condition of the patient. METHODS: We analyzed the liver volumes of 180 Japanese donor candidates and 160 Swiss patients with normal livers to develop a new formula. The dataset was randomly divided into two subsets, the test and validation sample, stratified by race. The new formula was validated using 50 LDLT recipients. RESULTS: Without using body weight-related variables, age, thoracic width measured using computed tomography, and race independently predicted the total liver volume (TLV). A new formula: 203.3-(3.61×age)+(58.7×thoracic width)-(463.7×race [1=Asian, 0=Caucasian]), most accurately predicted the TLV in the validation dataset as compared with any other formulas. The graft volume for LDLT was correlated with the postoperative prothrombin time, and the graft volume/SLV ratio calculated using the new formula was significantly better correlated with the postoperative prothrombin time than the graft volume/SLV ratio calculated using the other formulas or the graft volume/body weight ratio. CONCLUSIONS: The new formula derived using the age, thoracic width and race predicted both the TLV in the healthy patient group and the SLV in LDLT recipients more accurately than any other previously reported formulas.

Connexin43 Inhibition Prevents Human Vein Grafts Intimal Hyperplasia.

Venous bypass grafts often fail following arterial implantation due to excessive smooth muscle cells (VSMC) proliferation and consequent intimal hyperplasia (IH). Intercellular communication mediated by Connexins (Cx) regulates differentiation, growth and proliferation in various cell types. Microarray analysis of vein grafts in a model of bilateral rabbit jugular vein graft revealed Cx43 as an early upregulated gene. Additional experiments conducted using an ex-vivo human saphenous veins perfusion system (EVPS) confirmed that Cx43 was rapidly increased in human veins subjected ex-vivo to arterial hemodynamics. Cx43 knock-down by RNA interference, or adenoviral-mediated overexpression, respectively inhibited or stimulated the proliferation of primary human VSMC in vitro. Furthermore, Cx blockade with carbenoxolone or the specific Cx43 inhibitory peptide 43gap26 prevented the burst in myointimal proliferation and IH formation in human saphenous veins. Our data demonstrated that Cx43 controls proliferation and the formation of IH after arterial engraftment.

Percepción del dolor en pacientes postoperados de cirugía cardiaca

Pain is defined as an unpleasant sensory or emotional experience, associated with tissue damage, that is a reality linked to the surgical procedure and the postoperative period. Objective: Knowing the degree of pain experienced by patients after cardiac surgery, depending on the type of intervention they underwent, over the post-operative period in an intensive care unit (ICU). Method: Descriptive observational study. Pain was assessed by the visual analog scale (VAS), going from 0 to 10, thereby obtaining the first VAS1 assessment at 2 h post-extubation and every 8 hours thereafter up to 48 hours or until discharge to floor VAS7. It included patients having undergone cardiac surgery [valve surgery, bypass, combined procedure (including valve surgery and bypass) and mediastinitis]. Data were processed using Spss.v 20. Results: 120 patients 70 years old on average (standard deviation (SD): 13.3 years old) were included, out of which 70% were male. 40.8% of them had underwent bypass coronary revascularization. Patients subjected to the bypass technique showed an VAS1 mean value of 4.35 (SD: 2.45), unlike those subjected to valve surgery, who showed a mean value of 2.89 (SD: 2.27), those subjected to the combined procedure, who showed a mean value of 3.87 (SD: 2.90), and those with mediastinitis, who showed a mean value of 3.33 (SD: 3.51); (p < 0.031). 28.5% of patients had underwent revascularization (n = 49 ) by an internal mam mary artery (IMA) graft. These patients showed a mean value for VAS1 of 5.4 (SD: 1.89), unlike those who had underwent a combined procedure [IMA and saphenous vein (SV)], who showed a mean value of 3.9 (SD: 2.6), and those who had underwent a SV procedure , who showed a mean value of 3.5 (SD: 2.1); (p < 0.045). Conclusions: Patients having underwent bypass and IMA procedures perceive more pain than in other cardiac surgery and graft interventions

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In the past 2 decades, there has been an increase in both basic science research detailing the anatomy and biomechanics of the native posterior cruciate ligament (PCL) and outcome studies evaluating manage- ment of the ruptured PCL. While the methodology of the latter continues to improve, results based on the current level of evidence must be interpreted cautiously (18). The focus of many recent studies has been double-bundle versus single-bundle reconstruction techniques. The theoretical advantage goes to double-bundle techniques, but a clinical difference in outcome has not been consistently demonstrated (8,17). Some biomechanical studies have reported improved control of posterior laxity with double-bundle reconstruc- tion; however, results appear to be more dependent on tunnel position and graft tensioning (13). In acute isolated symptomatic PCL injuries in which the posteromedial bundle and the meniscofemoral ligament remain intact, a single-bundle augmentation procedure may be the preferred surgical technique. In more complex PCL ruptures with associated injuries involving the posterolateral structures (PLS) or medial collateral ligament, more benefit may be derived from double-bundle reconstruction. Again, cadaveric testing of double-bundle PCL reconstruction has not consistently outperformed single-bundle techniques in combined PCL/PLS injury (3). Multi-ligamentous injuries are commonly associated with PCL rupture (15), and their management should be considered carefully in the decision to reconstruct one or both of the functionally dis- tinct PCL bundles. However, the technical complexity of double-bundle reconstruction, the longer surgical time required, as well as the inconclusive clinical outcome are all factors that must be weighed carefully.

Pulmonary valve stenosis due to undifferentiated pleomorphic sarcoma

Pulmonary artery sarcomas are uncommon intracardiac tumours with poor prognosis. We report the case of a 69-year-old woman in good health presenting with rapidly progressive dyspnoea and an unfamiliar systolic murmur. Echocardiography revealed pulmonary valve stenosis due to an obstructing mobile mass. Imaging studies confirmed the presence of a contrast-enhancing lesion adherent to the valve, extending into the pulmonary trunk and right ventricular outflow tract, and suggestive of malignancy. Endovascular biopsy was attempted with no success. Surgical resection with autologous graft valve replacement and pulmonary artery reconstruction was performed. Postoperative histological examination confirmed the diagnosis of an undifferentiated pleomorphic sarcoma. Pulmonary artery sarcoma should be considered as a rare differential diagnosis in patients presenting with dyspnoea and a crescendo-decrescendo systolic murmur increasing with inspiration. Echocardiography is a useful first diagnostic approach but multi-imaging assessment is almost always necessary for definite diagnosis. Our case provides insights into the challenges met by cardiologists, radiologists and cardiac surgeons in the management of such cases.