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Sinus of Valsalva aneurysm rupture is a rare condition with a great potential for morbidity and mortality if not promptly diagnosed and managed. We present an unusual non-infected sinus of Valsalva aneurysm rupture in a 47-year-old female. This case report, a likely presentation of a late congenital heart defect, highlights the need for a high index of suspicion in a patient with atypical history of congestive cardiac failure.

Since its emergence in March 2020, the SARS-CoV-2 global pandemic has produced more than 116 million cases and 2.5 million deaths worldwide. Despite the enormous efforts carried out by the scientific community, no effective treatments have been developed to date. We applied a novel computational pipeline aimed to accelerate the process of identifying drug repurposing candidates which allows us to compare three-dimensional protein structures. Its use in conjunction with two in silico validation strategies (molecular docking and transcriptomic analyses) allowed us to identify a set of potential drug repurposing candidates targeting three viral proteins (3CL viral protease, NSP15 endoribonuclease, and NSP12 RNA-dependent RNA polymerase), which included rutin, dexamethasone, and vemurafenib. This is the first time that a topological data analysis (TDA)-based strategy has been used to compare a massive number of protein structures with the final objective of performing drug repurposing to treat SARS-CoV-2 infection.

Background and Aim: The coronavirus disease 2019 (COVID-19) pandemic has seen the cancellation of elective cardiac surgeries worldwide. Here we report the experience of a cardiac surgery unit in a developing country in response to the COVID-19 crisis., Methods: From 6th April to 12th June 2020, 58 patients underwent urgent or emergency cardiac surgery. Data was reviewed from a prospectively entered unit-maintained cardiac surgery database. To ensure safe delivery of care to patients, a series of strict measures were implemented which included: a parallel healthcare system maintaining a COVID-19 cold site, social isolation of patients for one to 2 weeks before surgery, polymerase chain reaction testing for COVID-19, 72 hours before surgery, discrete staff assigned only to cardiac surgical cases socially isolated for 2 weeks as necessary., Results: The mean age at surgery was 59.7 ± 11 years and 41 (70.7%) were male. Fifty-two patients were hypertensive (90%), and 32 were diabetic (55.2%). There were three emergency type A aortic dissections. Forty-seven patients underwent coronary artery bypass graft surgery with all but three performed off-pump. Fourteen cases required blood product transfusion. One patient had postoperative pneumonia associated with chronic obstructive pulmonary disease. The median length of stay was 5.7 ± 1.8 days. All patients were discharged home after rehabilitation. There were no cases of COVID-19 infection among healthcare workers during the study period., Conclusion: These strategies allowed us to maintain a service for urgent and emergency procedures and may prove useful for larger countries when there is decrease in COVID-19 cases and planning for the restart of elective cardiac surgery., (© 2020 The Authors. Journal of Cardiac Surgery published by Wiley Periodicals LLC.)

Real-time decision making needs evaluating quantities of interest (QoI) in almost real time. When these QoI are related to models based on physics, the use of Model Order Reduction techniques allows speeding-up calculations, enabling fast and accurate evaluations. To accommodate real-time constraints, a valuable route consists of computing parametric solutions-the so-called computational vademecums-that constructed off-line, can be inspected on-line. However, when dealing with shapes and topologies (complex or rich microstructures) their parametric description constitutes a major difficulty. In this paper, we propose using Topological Data Analysis for describing those rich topologies and morphologies in a concise way, and then using the associated topological descriptions for generating accurate supervised classification and nonlinear regression, enabling an almost real-time evaluation of QoI and the associated decision making.

Structural changes to the wall of the left atrium are known to occur with conditions that predispose to Atrial fibrillation. Imaging studies have demonstrated that these changes may be detected non-invasively. An important indicator of this structural change is the wall's thickness. Present studies have commonly measured the wall thickness at few discrete locations. Dense measurements with computer algorithms may be possible on cardiac scans of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). The task is challenging as the atrial wall is a thin tissue and the imaging resolution is a limiting factor. It is unclear how accurate algorithms may get and how they compare in this new emerging area. We approached this problem of comparability with the Segmentation of Left Atrial Wall for Thickness (SLAWT) challenge organised in conjunction with MICCAI 2016 conference. This manuscript presents the algorithms that had participated and evaluation strategies for comparing them on the challenge image database that is now open-source. The image database consisted of cardiac CT (n=10) and MRI (n=10) of healthy and diseased subjects. A total of 6 algorithms were evaluated with different metrics, with 3 algorithms in each modality. Segmentation of the wall with algorithms was found to be feasible in both modalities. There was generally a lack of accuracy in the algorithms and inter-rater differences showed that algorithms could do better. Benchmarks were determined and algorithms were ranked to allow future algorithms to be ranked alongside the state-of-the-art techniques presented in this work. A mean atlas was also constructed from both modalities to illustrate the variation in thickness within this small cohort., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

The elaboration of biomimetic materials inspired from the specific structure of native bone is one the main goal of tissue engineering approaches. To offer the most appropriate environment for bone reconstruction, we combined electrospinning and electrospraying to elaborate an innovative scaffold composed of alternating layers of polycaprolactone (PCL) and hydroxyapatite (HA). In our approach, the electrospun PCL was shaped into a honeycomb-like structure with an inner diameter of 160 μm, capable of providing bone cells with a 3D environment while ensuring the material biomechanical strength. After 5 days of culture without any differentiation factor, the murine embryonic cell line demonstrated excellent cell viability on contact with the PCL-HA structures as well as active colonization of the scaffold. The cell differentiation, as tested by RT-qPCR, revealed a 6-fold increase in the expression of the RNA of the Bglap involved in bone mineralization as compared to a classical 2D culture. This differentiation of the cells into osteoblasts was confirmed by alkaline phosphatase staining of the scaffold cultivated with the cell lineage. Later on, organotypic cultures of embryonic bone tissues showed the high capacity of the PCL-HA honeycomb structure to guide the migration of differentiated bone cells throughout the cavities and the ridge of the biomaterial, with a colonization surface twice as big as that of the control. Taken together, our results indicate that PCL-HA honeycomb structures are biomimetic supports that promotes in vitro osteocompatibility, osteoconduction, and osteoinduction and could be suitable for being used for bone reconstruction in complex situations such as the repair of maxillofacial defects.

Interpenetrating polymer networks (IPNs) have gained great attention for a number of biomedical applications due to their improved properties compared to individual components alone. In this study, we investigated the capacity of newly-developed naturally-derived IPNs as potential biomaterials for tissue engineering. These IPNs combine the biologic properties of a fibrous fibrin network polymerized at the nanoscale and the mechanical stability of polyethylene oxide (PEO). First, we assessed their cytotoxicity in vitro on L929 fibroblasts. We further evaluated their biocompatibility ex vivo with a chick embryo organotypic culture model. Subcutaneous implantations of the matrices were subsequently conducted on nude mice to investigate their biocompatibility in vivo. Our preliminary data highlighted that our biomaterials were non-cytotoxic (viability above 90%). The organotypic culture showed that the IPN matrices induced higher cell adhesion (across all the explanted organ tissues) and migration (skin, intestine) than the control groups, suggesting the advantages of using a biomimetic, yet mechanically-reinforced IPN-based matrix. We observed no major inflammatory response up to 12 weeks post implantation. All together, these data suggest that these fibrin-based IPNs are promising biomaterials for tissue engineering., Competing Interests: The authors declare no conflict of interest.

Glass sheets covered with aligned electrospun silk fibroin (Bombyx mori) were compared to tissue culture-treated Thermanox® coverslips, using an organotypic culture method. Different chick embryo organ behaviours were analysed in terms of circularity, cell growth and cell adhesion after being cultivated in contact with these two materials. The circularity (cell layer shape corresponding to the trend of the biomaterials to induce a specific directionality) depends on the organ used when in contact with silk fibroin. This biomaterial induced higher cell adhesion (kidney) or lower cell adhesion (spine) compared to Thermanox. Cell growth, represented by the cell layer area (mm 2 ), was also drastically reduced (gonad) or increased (blood vessel) on the silk fibroin. Organotypic culture is a rapid, cost effective and relatively simple method to evaluate different parameters, allowing prescreening of morphology and cytocompatibility to select the appropriate applications for new biomaterials. In the present study we compared the morphology of different organotypic cultures on orientated silk and Thermanox as growth supports to rapidly evaluate the benefit of a silk-based biomaterial for tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd., (Copyright © 2014 John Wiley & Sons, Ltd.)

Thin-Film-Transistors Liquid-Crystal Display has become a standard in the field of displays. However, the structure of these devices presents interest not only in that field, but also for biomedical applications. One of the key components, called here TFT substrate, is a glass substrate with a dense and large array of thousands of transparent micro-electrodes that can be considered as a large scale multi-electrode array(s). Multi-electrode array(s) are widely used for in vitro electrical investigations on neurons and brain, allowing excitation, registration, and recording of their activity. However, the range of application of conventional multi-electrode array(s) is usually limited to some tens of cells in a homogeneous cell culture, because of a small area, small number and a low density of the micro-electrodes. TFT substrates do not have these limitations and the authors are currently studying the possibility to use TFT substrates as new tools for in vitro electrical investigation on tissues and organoids. In this respect, experiments to determine the cyto-biocompatibility of TFT substrates with tissues were conducted and are presented in this study. The investigation was performed using an organotypic culture method with explants of brain and liver tissues of chick embryos. The results in term of morphology, cell migration, cell density and adhesion were compared with the results from Thermanox ® , a conventional plastic for cell culture, and with polydimethylsiloxane, a hydrophobic silicone. The results with TFT substrates showed similar results as for the Thermanox ® , despite the TFT hydrophobicity. TFT substrates have a weak cell adhesion and promote cell migration similarly to Thermanox ® . It could be concluded that the TFT substrates are cyto-biocompatible with the two studied organs.

Purpose: The increasing demand for esthetically pleasing results has contributed to the use of ceramics for dental implant abutments. The aim of this study was to compare the biological response of epithelial tissue cultivated on lithium disilicate (LS 2 ) and zirconium oxide (ZrO 2 ) ceramics. Understanding the relevant physicochemical and mechanical properties of these ceramics will help identify the optimal material for facilitating gingival wound closure., Methods: Both biomaterials were prepared with 2 different surface treatments: raw and polished. Their physicochemical characteristics were analyzed by contact angle measurements, scanning white-light interferometry, and scanning electron microscopy. An organotypic culture was then performed using a chicken epithelium model to simulate peri-implant soft tissue. We measured the contact angle, hydrophobicity, and roughness of the materials as well as the tissue behavior at their surfaces (cell migration and cell adhesion)., Results: The best cell migration was observed on ZrO 2 ceramic. Cell adhesion was also drastically lower on the polished ZrO 2 ceramic than on both the raw and polished LS 2 . Evaluating various surface topographies of LS 2 showed that increasing surface roughness improved cell adhesion, leading to an increase of up to 13%., Conclusions: Our results demonstrate that a biomaterial, here LS 2 , can be modified using simple surface changes in order to finely modulate soft tissue adhesion. Strong adhesion at the abutment associated with weak migration assists in gingival wound healing. On the same material, polishing can reduce cell adhesion without drastically modifying cell migration. A comparison of LS 2 and ZrO 2 ceramic showed that LS 2 was more conducive to creating varying tissue reactions. Our results can help dental surgeons to choose, especially for esthetic implant abutments, the most appropriate biomaterial as well as the most appropriate surface treatment to use in accordance with specific clinical dental applications., Competing Interests: No potential conflict of interest relevant to this article was reported.

In this work, we have investigated the potential of perfluoropolyether (PFPE) polymers for use in biomaterial applications, especially in cell culture and tissue engineering. PFPE substrates were synthesized by the photocuring of liquid PFPE urethane dimethacrylate. These surfaces were then modified by ECM protein coatings and microstructuration, to promote cell adhesion and migration. The surface properties of PFPE and PDMS (used as a reference) samples were studied by static contact angle measurements and AFM imaging. Both polymer surfaces were hydrophobic, having sessile air-water contact angles superior to 100°. Collagen and fibronectin coatings were found to change the wettability of PFPE and PDMS samples. The biological testing of substrates was done using a liver organotypic culture to evaluate the migration and density of liver cells. The results over seven days of culture demonstrated that the migration and density of cells cultured under untreated PFPE were higher than the migration and density of cells cultured under PDMS. ECM protein coatings enhanced cell migration from liver explants cultured on PFPE or PDMS. Furthermore, these coatings were more efficient in the case of a PFPE sample. From a second series of tests, in which the PFPE was microstructured, it was found that microstructures promoted the formation of a 3D cell layer. These results indicate that PFPE polymers have a potential for use in the development of biomaterials for tissue engineering and cell culture., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: Ceramics are widely used materials for prosthesis, especially in dental fields. Despite multiple biomedical applications, little is known about ceramic surface modifications and the resulting cell behavior at its contact. The aim of this study is to evaluate the biological response of polished versus glazed surface treatments on lithium disilicate dental ceramic., Methods: We studied a lithium disilicate ceramic (IPS e.max(®) Press, Ivoclar Vivadent) with 3 different surface treatments: raw surface treatment, hand polished surface treatment, and glazed surface treatment (control samples are Thermanox(®), Nunc). In order to evaluate the possible modulation of cell response at the surface of ceramic, we compared polished versus glazed ceramics using an organotypic culture model of chicken epithelium., Results: Our results show that the surface roughness is not modified as demonstrated by equivalent Ra measurements. On the contrary, the contact angle θ in water is very different between polished (84°) and glazed (33°) samples. The culture of epithelial tissues allowed a very precise assessment of histocompatibility of these interfaces and showed that polished samples increased cell adhesion and proliferation as compared to glazed samples., Significance: Lithium disilicate polished ceramic provided better adhesion and proliferation than lithium disilicate glazed ceramic. Taken together, our results demonstrate for the first time, how it is possible to use simple surface modifications to finely modulate the adhesion of tissues. Our results will help dental surgeons to choose the most appropriate surface treatment for a specific clinical application, in particular for the ceramic implant collar., (Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Soft tissue adhesion on titanium represents a challenge for implantable materials. In order to improve adhesion at the cell/material interface we used a new approach based on the molecular recognition of titanium by specific peptides. Silk fibroin protein was chemically grafted with titanium binding peptide (TiBP) to increase adsorption of these chimeric proteins to the metal surface. A quartz crystal microbalance was used to quantify the specific adsorption of TiBP-functionalized silk and an increase in protein deposition by more than 35% was demonstrated due to the presence of the binding peptide. A silk protein grafted with TiBP and fibronectin-derived arginine-glycine-aspartic acid (RGD) peptide was then prepared. The adherence of fibroblasts on the titanium surface modified with the multifunctional silk coating demonstrated an increase in the number of adhering cells by 60%. The improved adhesion was demonstrated by scanning electron microscopy and immunocytochemical staining of focal contact points. Chick embryo organotypic culture also revealed strong adhesion of endothelial cells expanding on the multifunctional silk peptide coating. These results demonstrated that silk functionalized with TiBP and RGD represents a promising approach to modify cell-biomaterial interfaces, opening new perspectives for implantable medical devices, especially when reendothelialization is required., (Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Metal injection molding (MIM) is a near net shape manufacturing method that allows for the production of components of small to moderate size and complex shape. MIM is a cost-effective and flexible manufacturing technique that provides a large innovative potential over existing methods for the industry of implantable devices. Commercially pure titanium (CP-Ti) samples were machined to the same shape as a composite feedstock with titanium and polyoxymethylene, and these metals were injected, debinded and sintered to assess comparative biological properties. Moreover, we treated MIM-Ti parts with BIOCOAT®, BIODIZE® and BIOCER®, three different anodic oxidation techniques that treat titanium using acid, alkaline and anion enriched electrolytes, respectively. Cytocompatibility as well as morphological and chemical features of surfaces was comparatively assessed on each sample, and the results revealed that MIM-Ti compared to CP-Ti demonstrated a specific surface topography with a higher roughness. MIM-Ti and BIOCER® samples significantly enhanced cell proliferation, cell adhesion and cell differentiation compared to CP-Ti. Interestingly, in the anodization post-treatment established in this study, we demonstrated the ability to improve osseointegration through anionic modification treatment. The excellent biological response we observed with MIM parts using the injection molding process represents a promising manufacturing method for the future implantable devices in direct contact with bones., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Aim: To investigate the effects of a neonatal low-protein diet on the morphology of myotubes in culture and the expression of key proteins that regulate myogenesis in young and adult rats., Methods: Male Wistar rats (n = 18) were suckled by mothers fed diets containing 17% protein (controls, C) or 8% protein (undernourished, UN). All rats were fed a normal protein diet after weaning. Muscles were removed from the legs of 42-, 60- and 90-day-old rats. Muscle cells were cultured to assess cell number, morphology and the expression of major proteins involved in myogenesis (Pax7, cadherins, β1 integrin, IL-4Rα and myogenin) by western blotting. IL-4 levels in culture supernatants were measured by ELISA., Results: Offspring from mothers fed a low-protein diet showed a lower body weight gain. Cell number and myotube expansion were reduced in cultured muscle cells from UN, but the expression of myogenic marker proteins was unaltered., Conclusions: Dietary restriction during lactation had no impact on the synthesis of myogenic marker proteins, and myocyte differentiation occurred normally in the muscles of offspring aged 42, 60 or 90 days. Nevertheless, the number and morphology of the myotubes are altered.

Woven poly(ethylene terephthalate) (PET) is widely used in implantable medical devices. Upon implantation, fibrinogen interacts with the PET and changes conformation, such that the fibrinogen P2 epitope may become exposed. This allows inflammatory cells to interact with the material. In this study we have coated PET with heparin and show that this decreases PET hydrophobicity and the presence of the fibrinogen P2 epitope on the material surface. In addition, we show that heparin-induced reduction of PET hydrophobicity correlates with decreased exposure of the fibrinogen P2 epitope and reduced adhesion of monocytes. Reduction of PET hydrophobicity was furthermore associated with reduced PMN elastase production and decreased interaction between PET and embryonic chicken tissue. We conclude that the heparin coating-induced decrease in PET hydrophobicity is associated with decreased interaction between PET and inflammatory cells. Independent of this interaction, the hydrophobic nature of the heparin coating is related to tissue interaction as demonstrated by a reduction in adhesion, growth and spreading of tissue on PET. The combination of these properties makes heparin coating a candidate for improving biocompatibility of PET.

We have synthesized titanium-based alloys containing molybdenum and tantalum elements by powder metallurgy. The microstructure, the residual porosity and the mechanical properties of the sintered Ti-Mo and Ti-Ta-Mo alloys were investigated by using optical and electronic microscopy, X-ray diffraction, microhardness and compression tests. The cytocompatibility of the different alloys was evaluated by the assessment of bone cell density, migration and adhesion after 14 days incubation. All the alloys present a high ductility and an excellent cytocompatibility, which make these materials useful for medical implants.

Previous work has reported the results of a multidisciplinary effort producing a proof-of-concept on the use of pectic polysaccharides in the surface modification of medical devices. This study was designed to learn more about the capability of engineered rhamnogalacturonan-I (RG-I) fractions of apple pectin to control bone cell and macrophage behavior. Thermanox or polystyrene Petri dishes were surface modified with two different modified hairy regions (MHRs) obtained by different enzymatic liquefaction processes of apples differing in relative amounts and lengths of their neutral side chains: (long-haired) MHR-alpha and (short-haired) MHR-B. Bone explants from 14-day-old chick embryos were cultured for 14 days on both pectic substrata. MHR-B promoted cell migration and differentiation, MHR-alpha did not. On MHR-alpha, J774.2 macrophages grew well, their percentage in G1 phase was decreased and in S phase increased, and they did not secrete either proinflammatory-cytokines or nitrites. Contrasting results were gained from macrophages on MHR-B, except for nitrite secretion. Thus, we conclude that coatings from tailored pectins show different biological activities in vitro and are potential innovative candidates for improving the biocompatibility of medical devices in various applications.

There is evidence that the shape of cells and their contact with a matrix direct the growth and the differentiation of both normal and cancer cells. Cells in 3D culture resemble the in vivo situation more closely than do those in conventional 2D cultures. We have studied the interactions and functions of B16F10 mouse melanoma cells, which spread and grow well on tissue culture polystyrene (tPS), when they were made to aggregate on cellulose-coated Petri dishes (CEL). This aggregation of melanoma cells on CEL was Ca2+ dependent and mediated by N-cadherins. The levels of N-cadherin and beta-catenin transcripts in cells cultured on CEL and tPS were similar, but those on CEL contained less beta-catenin protein. Immunoprecipitation and immunostaining showed that both N-cadherins and beta-catenins were present at the membranes of cells on CEL. Cells proliferated significantly more slowly after 48 h on CEL and the cellulose coating caused most of them to arrest in G1. We also compared the melanin contents and tyrosinase activity of cells on CEL and controls grown on tPS. Melanogenesis was induced in cells aggregated on CEL. A cellulose substrate thus appears to be an outstanding tool for studying cell-cell interactions and cell functions in 3D cultures.

Ti-based biocompatible alloys are especially used for replacing failed hard tissue. Some of the most actively investigated materials for medical implants are the beta-Ti alloys, as they have a low elastic modulus (to inhibit bone resorption). They are alloyed with elements such as Nb, Ta, Zr, Mo, and Fe. We have prepared a new beta-Ti alloy that combines Ti with the non-toxic elements Ta and Mo using a vacuum arc-melting furnace and then annealed at 950 degrees C for one hour. The alloy was finally quenched in water at room temperature. The Ti-12Mo-5Ta alloy was characterised by X-ray diffraction, optical microscopy, SEM and EDS and found to have a body-centred-cubic structure (beta-type). It had a lower Young's modulus (about 74 GPa) than the classical alpha/beta Ti-6Al-4V alloy (120 GPa), while its Vickers hardness remained very high (about 303 HV). This makes it a good compromise for a use as a bone substitute. The cytocompatibility of samples of Ti-12Mo-5Ta and Ti-6Al-4V titanium alloys with various surface roughnesses was assessed in vitro using organotypic cultures of bone tissue and quantitative analyses of cell migration, proliferation and adhesion. Mechanically polished surfaces were prepared to produce unorientated residual polished grooves and cells grew to a particularly high density on the smoother Ti-12Mo-5Ta surface tested.

The cytotoxicity caused by the debris resulting from wear of prostheses can produce major damage to tissues around the implant. We have compared particle internalization by macrophages and fibroblasts in vitro and analyzed cell death. J774.2 macrophages and L929 fibroblasts were incubated with 0.43 and 2.81 microm alumina particles or 0.45 and 3.53 microm polystyrene (PS) beads. Incubation of J774.2 cells with alumina particles of both sizes and 0.5 and 1.0 mg/ml PS beads significantly decreased cell numbers in a particle concentration-dependent manner. L929 cells were not affected by lower concentrations of 0.43 microm alumina particles (which aggregate at high concentrations) and they internalized 0.45 microm PS beads without any decrease in cell numbers. Particles were more cytotoxic for macrophages than for fibroblasts. Particles caused the size of both types of cells to increase in correlation with cytotoxicity. Trypan blue exclusion and lactate dehydrogenase release showed cell membrane leakage for both types of cells incubated with PS beads for 24 h. Apoptosis was assessed by annexin V-FITC, propidium iodide staining and assay of caspase 3 activity. Macrophage death appeared to depend on both necrosis, caused mainly by 3.53 microm PS beads, and apoptosis, mainly due to 0.45 microm PS beads. The release of the inflammatory cytokine IL-6 appears to be nonlinearly correlated with cytotoxicity. Thus, the size of the internalized particles affects macrophages and fibroblasts differently, and the increase in cell size can be used as a preliminary criterion of particle cytotoxicity in vitro.

Purpose: Embolic events during carotid angioplasty are a challenging problem. This experimental study was undertaken to determine the embolic risk after each stage of carotid angioplasty procedure., Methods: Five ex vivo carotid artery balloon angioplasties were performed on fresh carotid specimens. The carotid specimens were obtained from five patients who underwent an internal carotid artery bypass for stenosis >75%. Before the endovascular maneuvers and after each stage of the procedures, the specimens were flushed with 20 mL of saline solution. Small particulate emboli (diameter, <60 microm) were searched in all the effluents according to the Coulter technique. After this procedure, each effluent was also submitted to scanning electron microscopy., Results: When the stenosis was crossed with the guidewire or the balloon catheter, the number and the mean diameter of embolic particles did not change with three plaques (CP1, CP2, and CP3) and were increased with two plaques (CP4 and CP5). The maximal size of particles was 220 microm (CP5). After balloon angioplasty, the number and the mean diameter of particles increased with CP1, CP2, and CP3. With CP4 and CP5, the number of particles decreased, but their size increased. The maximal size of particles was 1100 microm (CP4)., Conclusion: Carotid balloon angioplasty generates embolic particles after each stage of the procedure. Techniques of prevention should then be effective from the initial step of the angioplasty procedure, and the selection of patients for carotid angioplasty remains crucial.

We have examined the link between the aggregation or spreading of cells adhering to substrata of differing biocompatibility and activation of the cyclic AMP (cAMP) pathway. We compared the rate at which the Mouse Swiss 3T3 fibroblasts attached to Cuprophan (CU), AN69 and a control plastic in the presence and absence of foetal calf serum (FCS). Serum had no effect on the kinetics of cell attachment to CU or AN69. Cells incubated in culture medium containing 10% FCS aggregated on CU, whereas they spread on AN69 and plastic. Aggregated cells contained significantly higher concentrations of cAMP than cells spreading, and aggregation was prevented by treatment with miconazole, an inhibitor of adenylyl cyclase. cAMP-dependent cell aggregation occurred on all three substrata in serum-free medium, suggesting that proteins adsorbed onto AN69 and plastic in the presence of serum helped protect the cells. Far less serum protein was adsorbed onto CU than onto AN69 or plastic, consistent with the similar increases in cAMP in cells attached to CU with or without serum.

Portal vein thrombosis complicating a trauma is rare. We report a case of portal vein thrombosis associated with esophageal rupture after a blast injury due to the explosion of a pressurized nitrogen bottle. Portal vein thrombosis was discovered during oesophageal reconstruction, 70 days after the initial injury. A favorable outcome was observed.

Glutaraldehyde (GTA) is used to cross-link collagen-based biomaterials, but these materials are often cytotoxic. In order to overcome this problem, we have proposed the use of the acyl azide methods with either hydrazine or diphenylphosphoryl azide (DPPA) as reagents. In this paper we determine the cytocompatibility of acyl azide- and GTA-treated pericardium in vitro, by an organotypic chick aorta culture technique developed for the evaluation of the propensity of vascular cells (both endothelial and smooth muscle cells) to migrate and grow on the surface of biomaterials. We first examined pericardium stabilization as a function of GTA concentration and time, so that we could minimize residual GTA molecules in the material. Treatment for 72 h with 0.05% GTA was optimal for thermal stabilization of the pericardium with a denaturation temperature (Td) of 86.8 degrees C, providing similar results to treatment with 0.6% GTA for 4 h (Td = 85.1 degrees C). Pericardium treated in this way was, however, poorly cytocompatible with little vascular cell migration and growth when compared with tissues treated by the acyl azide methods. The best results were obtained with 0.5% DPPA; treated tissues showed a high level of cross-linking (Td = 82.4 degrees C) and three-fold increases in cell growth and migration over those in a non-toxic control.

Permanent pacemaker electrode infection is rare but can be fatal. The authors report two cases presenting with spondylodiscitis, a previously described mode of presentation of valve endocarditis but not previously reported in this context. In one case, recurrent courses of antibiotics did not prevent repeated episodes of bacteraemia. In the second, the relapse of infection occurred at different sites of the vertebral column until surgical removal of the electrodes: the usual features of this pathology were observed: frequent but not constant infection at the site of the pacemaker implantation, making the diagnosis more difficult; delayed signs of spondylodiscitis after implantation of the pacemaker; recurrence of infection when antibiotic therapy alone was prescribed and, therefore, the need for surgical ablation of all implanted material. The authors underline the diagnostic value of transoesophageal echocardiography.

This a retrospective study of 19 patients presenting with chronic pancreatitis and benign stenosis of the common bile duct, who were followed up for periods ranging from 13 months to 48 months after biliary stenting (average 18 months). There were 18 men and one woman, aged between 38 and 65 years (average 49 years). The mean duration of the disease before stenting was seven years (range 1-25 years). Symptoms were present in ten patients: obstructive jaundice in four cases, cholangitis in three cases, and biliary colic in three cases. Nine patients without clinical complaints presented with chronic cholestasis. Endoscopic retrograde cholangiopancreatography (ERCP) showed 15 long, regular stenoses of the intrapancreatic course of the common bile duct, three short stenoses located at the upper margin of the head of the pancreas, and one biliary stenosis associated with peripheral compression by a cyst of the head of the pancreas. Forty endoscopic biliary stenting procedures were performed in the 19 patients over a six-year period. Successful insertion of the prosthesis was achieved in 39 cases. Two complications occurred: one duodenal ulceration and one stent migration into the bile duct. The mean duration of biliary stenting was ten months. Only two patients (10%) had complete clinical, biological, and radiological recovery. Complete failure of biliary stenting was observed in six patients (31%). Eleven patients (59%) had partial results: six (31%) had biological improvement although the biliary stricture persisted, and five were clinically asymptomatic but had cholestasis, and still presented with biliary stenosis in four cases.(ABSTRACT TRUNCATED AT 250 WORDS)

We report a case of aortic endothelioma revealed by intestinal metastasis in a man who was admitted for severe anemia, left heart failure, and fatal ileo-mesenteric infarction. This is the 13th published case of aortic endothelioma, and the first case revealed by intestinal metastasis. It illustrates the value of the magnetic resonance imaging for the detection of an aortic tumor when intestinal angiosarcoma has been diagnosed. The surgical treatment could improve an otherwise very poor prognosis.

The authors report a case of angiosarcoma of the descending thoracic aorta presenting with a metastasis of the small intestine. This is a very rare tumour in this localisation, two cases having been described among the 28 cases of aortic tumour reported in the literature.