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Introduction Primary adipose cardiac tumors are divided into two different entities: lipomatous hypertrophy of the interatrial septum (LHIS) and lipomas. Lipomas are usually benign masses of unknown pathogenesis. Currently few cases are reported in literature, with no differences in gender distribution. Clinical Case A 63–year–old patient presented to our emergency room complaining chest pain and dyspnea on exercise. Her medical history shows severe obesity, hypertention, past surgical removal of several systemic lipomas (uterus lipoma, right ovary lipoma, right thigh and leg lipoma, right forearm and wrist lipoma). A coronary angiography was performed showing the lack of angiographically significant lesions. On suspicion of microvascular angina, she began therapy with Ranolazine and Beta–blockers. Echocardiographic examination showed a lipomatous interatrial septum in the postero–superior tract with a maximum of 22.5mm thickness (image 1). At 12 months, chest CT and MRI scan showed a hyperintense mass on interatrial septum measuring 32x34mm. The formation, mainly protruding in the right atrium, does not obstruct the outlet of the hollow veins, nor the outlet of the pulmonary veins. No hemodynamic compromise and compression were detected. Last follow–up visit our patient presented dyspnea and chest pain, the echocardiogram showed a slight increase of the mass size (see image), with unchanged thicknesses and biventricular pump function. Conclusions In literature there is no evidence of malignant transformation of cardiac lipomas, however well–differentiated cell tumors can coexist with liposarcomas. There are no guidelines for the treatment of cardiac lipomas, radical resection is practiced in the majority of symptomatic patients and should be considered in all patients with cardiac lipoma. Asymptomatic lipomas can excessively grow up and infiltrate into the myocardium, resulting in negative outcomes to a possible subsequent resection. According to the worsening of the clinical course, the patient under consideration was referred for lipoma resection surgery.

Introduction Diffuse large B–cell lymphoma (DLBCL) is the most common subtype of non–Hodgkin‘s lymphoma in adults. Rituximab and Anthracycline–based chemotherapy are the standard treatment, complete remission (CR) is achived in approximately 67% of patients. About one third of patients have refractory disease or relapse after standard therapy, mostly within 5 years of achieving CR. Clinical Case A 62–year–old patient, current smoker, without previous cardiovascular diseases presented to our ER for dyspnea and asthenia. Medical history showed GBC–DLBCL at third stage that achieved CR with R–CHOP therapy and intrathecal prophylaxis. The ECG documented sinus tachycardia with normal ventricular repolarization. Arterial blood gas analysis showed a condition of respiratory distress (pO2 71 mmHg, pCO2 27 mmHg). For suspicion of pulmonary embolism, chest CT with contrast was done showing a bulky mass extending from the right atrium to the right ventricle, also involving the pericardial sac (image 1). Transthoracic echocardiography showed a bulky mass (area 31 cm2) occupying almost the entire right atrium (5.9 x 4.4 cm) and extended, through the tricuspid valve, into the right ventricle, displacing the interventricular septum (image 2). Endomyocardial biopsy confirmed the diagnosis of GBC–DLBCL cardiac recurrence. Assumed the good systolic function of the left ventricle and the age of the patient, chemotherapy debulking was performed with Gemcitabine, followed by R–CHOP and MTX. One month after therapy post–treatment Total Body CT shows a good response with no evidence on echocardiogram of pathological tissue in the right ventricle (image 3). Conclusions Cardiac DLBCL is a rare tumor with few cases reported in the literature. There is currently no standard therapy, particularly for those who are unsuitable for high–dose chemotherapy a/o autologous stem cell transplantation. The multidisciplinary cardiological and hematological approach has proved to be fundamental these patient‘s therapeutic management.

Grafting polymerisation of methyl methacrylate and ethyl acrylate onto linen and cotton was carried out in order to reinforce these materials, when they underwent degradation. Take into account this aim, an artificially ageing was performed onto cellulose based textiles by metaperiodate oxidation, in order to obtain degraded model samples. Carbonyl groups were introduced in the cellulose and used as photosensitive agents, allowing the formation of radical sites during the polymerisation reaction, that started by irradiating the substrate by ultraviolet light. In this paper the effectiveness of grafting polymerisation as a method for textile conservation is discussed, starting from the results obtained from several characterisations, as the grafting yields and the grafting efficacy evaluation, the DSC analysis, the FTIR spectroscopy and the SEM observations. Moreover the consolidating and the protective effects were investigated by evaluating the mechanical properties and the wetting behaviour of the grafted samples, and comparing them with the original and aged substrates. The mechanical strength of cellulose based textiles has been improved, as well as the wetting behaviour has been enhanced.

two different diisocyanates were investigated as co-monomers for in situ polymerisation of poly(urethane-urea) into Neapolitan yellow tuff for conservation and restoration purpose. The obtained copolymers were characterised by means of FTIR spectroscopy, whereas the protective and consolidating efficiency of the performed treatments was evaluated through water capillary absorption, water vapour permeability and abrasion resistance measurements. The distribution and the penetration depth of the synthesized copolymer were also analysed applying micro-FTIR. The morphology of treated tuff was investigated by SEM. It was shown that comparatively higher protective and consolidating properties are achieved by using 1,6-diisocyanatohexane as monomer for in situ polymerisation.

With the aim of identifying the most suitable commercial water dispersed polyacrylates to be used in the conservation and restoration field, the properties of four commercial polymers were compared with those shown by Primal AC33, a product made and commercialized by Rohm and Haas, widely used as a consolidating and adhesive agent for art works, and nowadays out of production. Chemical, molecular, thermal, mechanical and optical investigation techniques were applied on films obtained from the polymer water dispersions cast at room temperature. Selected polymers were characterized before and after artificial aging under a xenon-arc lamp in order to determine their photooxidative stability. It was found that Acrilem IC15, among the selected products, was the material with improved physico-chemical properties and photooxidative stability with respect to that shown by the discontinued Primal AC33.

With the aim of better understanding the phenomena related to the application of polymeric materials on natural fiber textiles for restoration purposes, six commercial polymers based on acrylic and acetovinylic monomers are tested on modem cotton textiles. Cotton samples are impregnated with water dispersions of these polymers. The morphology of the polymeric films formed on the surfaces of the fibers, the chromatic and consolidating effects of the applications, and the adhesive properties of the polymers are investigated. The morphology of the films coating the fibers is independent of the morphology of the fibers constituting the textile substrate. There are no relevant chromatic effects related to the application of polymeric materials on cotton fabrics, indicating that treatments should be compatible with the aesthetic of cotton items. The consolidating effect of application is evaluated on cotton yarns artificially degraded in HCl solution, and depends strictly on the amount of polymer applied. Peel strength values exhibited by cotton samples prepared by compression molding and under vacuum suggest that the most useful adhesive agents are those with a Tg slightly lower than room temperature.

Crystallization of an ethylene–propylene copolymer (E/P) filled with diverse weight percentages of titanium dioxide (TiO2) was performed under isothermal and nonisothermal conditions to investigate the influence of the inorganic substance on the nucleation and growth mechanisms of the matrix. The overall and radial crystallization rates of the composite materials were measured using, respectively, differential scanning calorimetry (DSC) and optical microscopy. The nucleation density of E/P spherulites as a function of composition was investigated by scanning electron microscopy (SEM), revealing a nucleating effect of TiO2. A comparison between the spherulitic texture of specimens showed a higher fineness of the composites relative to the neat matrix, whereas no changes of surface nucleation density were appreciable among composites within the explored compositional range. The thermal behavior is discussed in the light of the enhanced thermal conductivity of polymer composites, which conciliates the crystallization kinetics of the matrix, analyzed using the Avrami equation, to optical and SEM observations. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3409–3416, 2003

One of the major problems in automatic woven-fabric recognition is how to detect the areas of interlacing warp and weft yams. This problem is termed ‘crossed-points detection’. With a non-periodic design, such as flowers, which may sometimes occur over a woven-fabric background, tbe problem of crossed-points detection becomes very difficult. In this work, we propose a new and fully automatic method based on Fourier image-analysis techniques. The application of this method to simple woven fabric, as well as to fabric with skewness or with non-periodic design, demonstrates the ability to solve such crossed-points-detection problems. Finally the algorithm is evaluated visually by superposing the detected grid image on the initial woven-fabric image. All the detected crossed-points are displayed independently and may be saved as file-format images for further processing.

The effect on the electrical properties of polymethylmethacrylate polymer containing liquid crystal as dispersed molecules is investigated in the temperature range 30-100°C and the frequency ange from 100 Hz to 10 kHz. It is found that increasing the liquid crystal content enhances the ac-impedance, decreases the ac-loss conductivity and decreases the value of the dielectric constant. The decrease in the ac-impedance with increasing frequency is associated with a dramatic increase in the ac-loss conductivity at frequencies higher than 1 kHz. The decrease in the ac-conductivity with increasing the dispersed liquid crystal phase is attributed to the reduction of the mobility of the charge carriers. Thus, the dielectric property of the system improves.

Melt rheology, phase morphology and properties of (60/40) isotactic polypropylene/ethylene-co-propylene (iPP/EPR) blends containing EPR copolymer synthesized by means of a titanium based catalyst with very high stereospecific activity (EPRTi) were compared to that of (60/40) iPP/EPR blends containing EPR copolymer synthesized by using a traditional vanadium based catalyst (EPRV). It was found that both the melts are to be classified `negative deviation blends' and that for such a composition the copolymer represents the dispersed phase. SEM investigations showed in fact that the EPR phase segregate in to irregular shaped domains localized in the core of the bars, the dispersion coarseness increasing with an increase in the ratio between the EPR viscosity and iPP viscosity. At low temperatures the iPP impact strength was improved, comparatively better properties being shown by the blends containing the EPRV copolymer. The different behaviour of EPRTi and EPRV phases as impact modifiers was ascribed to their both different dispersion degree and microstructure. For test temperatures higher than EPR Tg the ethylenic crystallinity exhibited by the EPRTi phase was considered to induce toughening deterioration by decreasing tie molecules density in the EPRTi domains, notwithstanding the beneficial effect of the ethylenic build-up. The reduction in iPP crystallinity index (Xc) value found for iPP/EPRTi blends indicated a strong interference of the crystallization process of EPRTi ethylenic sequences with the iPP crystallization process. SAXS investigations revealed in addition that the iPP/EPRTi materials are characterized by an amorphous interlamellar layer (La) higher than that shown by plain iPP and iPP phase crystallized in presence of EPRV copolymer. Taking also into account results obtained studying blends containing lower content of such EPR phases composition effects were investigated. WAXS studies showed that with increasing copolymer content the ratio between the apparent crystal size of iPP phase grown in a direction perpendicular to the (110) crystallographic plane [D(110)] and that grown in direction perpendicular to the (040) crystallographic plane [D(040)] increases. Such an effect was related to an increased iPP nucleation density according to DSC results.

This chapter provides practical information for optimizing scanning of coronary artery bypass grafts and reading the images. Reading the images is best done on axial and multiplanar reformations and should include the evaluation of graft anastomoses and run-offs as well as the native vessels. The thoracic aorta and cardiac function should be considered in the reporting.

The phase morphology and structure of thermoplastic elastomers obtained from isotactic polypropylene (iPP) and ethylene—propylene random copolymer (EPR) blends by means of the dynamic curing of EPR rubbery component carried out during its melt mixing with iPP in a Banbury mixer at 180°C were investigated. Samples obtained by compression molding and by using isothermal crystallization conditions of the iPP phase were analyzed by means of differential scanning calorimetry, of optical, scanning, and transmission electron microscopy, and of wide-angle and small-angle X-ray diffraction. The influence of cooling below the melting point and of EPR molecular structure on the kinetic and thermodynamic parameters related to crystallization process of the iPP phase was also studied. It was found that the process of dynamic curing of the EPR component dramatically affects the development of the phase morphology and structure in the material. As a matter of fact, the blend containing the uncured EPR is characterized by the presence of iPP domains randomly distributed in the EPR rubbery matrix, whereas in the blend containing the cured EPR the iPP phase becomes the continuous phase crystallizing in a structure that resembles a cobweb tending to surround the EPR cured particles; moreover such an iPP cobweb appears to be contituted by row structures of stacked lamellae. It was found that the addition of EPR phase interferes dramatically with the crystallization process of the iPP, thus inducing drastic modification in its intrinsic morphology (size, neatness, regularity of spherulites, inner structure of spherulites, etc.). Such interference was found to be comparatively stronger when the iPP phase crystallizes in presence of cured EPR. The elastic behavior of the thermoplastic elastomer material was accounted for by applying the “leaf spring model” to the morphology and structure of the iPP phase crystallized in presence of cured EPR. © 1994 John Wiley & Sons, Inc.

Isotactic polypropylene (iPP) based blends containing as second component ethylene-propylene copolymers (EPR) having, for constant propylene (C3) content (wt/wt), different average molecular masses ( M w and/or M n ) and, for constant average molecular mass, different molecular mass distributions (MMD) were investigated. The study was undertaken to establish the influence of the melt phase viscosity ratio μ in determining the average particle size of the EPR phase in the vicinity of the minimum expected according to the Taylor-Tomotika theory for the average particle size versus log μ function, when μ is about equal to unity (in previous studies we have in fact reached μ values far above 1). Moreoever, we also report the effects of molecular mass and molecular mass distribution of the EPR phase on the melt rheological behaviour of iPP/EPR blends, on the mode and state of dispersion of the EPR phase in the melt, as well as, in the solid state after iPP crystallization in injection moulded samples, on the crystalline lamellar thickness and the thickness of the amorphous interlayer of iPP phase, and finally on the impact properties of blend materials. It should be pointed out that the apparent viscosity of all the iPP/EPR blends investigated is expected to obey the logarithm additivity rule that applies at constant temperature and shear rate. The application of the Cross-Bueche equation revealed that the zero-shear viscosity ηo of these iPP/EPR blends deviates positively from the logarithm additivity rule. Assuming that the crystallization of the iPP phase freezes the morphology of the EPR phase, a strict correlation is confirmed to exist between the values of EPR particle size and EPR particle size range, as measured by scanning electron microscopy on samples in the solid state, and μ value. The number average particle diameter ( D n ) and the particle size range of the EPR phase (D) are found to increase with increasing μ value as expected according to the Taylor-Tomotika theory. Finally, when the iPP phase crystallizes from its blends with EPR under non-isothermal conditions, the phase structure developed in the blends is characterized by lamellar thickness and interlamellar amorphous layer thickness, respectively, lower and higher than that shown by plain iPP.

A series of new acylic dichlorides were prepared from 4,4'-dihydroxybiphenyl and the ethylester of an ω-bromo alkyl-carboxylic acid. These dichlorides condensed with terephthalic dihydrazide. The resulting poly(ether-alkyl)hydrazides, whose general formula is [NHNHCOPhCONHNHCO(CH 2 ) m OPhPhO(CH 2 ) m CO] n (m= 3,4,5), showed different thermal behavior according to the value m. The crystallinity of the polymers increased with m while the T g and cyclization temperature to polyoxadiazoles decreased in the same direction

Nuclear magentic resonance (NMR) microimaging is now a well-accepted tool in medicine and biology, but, nothwithstanding considerable effort, its value as a microscopy technique in materials science is still questionable. In fact, although obtaining microimages of full uncut solid matter is very desirable, actual applications and results mostly concern images obtained with the help of a liquid-like contrast material, which is used in order to obtain narrow NMR lines [1]. True NMR images of solids can be obtained only with rather complex pulse sequences still in the experimental stage and with rather poor resolution [2]. Solid-state characterization of multiphase polymeric materials is highly desirable. Multilayer films for packaging, polymer blends for improving selected performances of existing materials and composites for structural applications are the three most important industrial fields of interest of multicomponent polymer-based materials [3]. The analysis of structures such as the above is currently possible only through manipulating, destructive techniques such as sectioning, fracturing, etching, staining and viewing by optical [4] or electron microscopy [5]. The purpose of this letter is to show that simple NMR microimaging methods can be successfully employed in the characterization of solid polymers. The poly(ethylene terephthalate) (PET) from Ciba used was a biaxially oriented transparent film of thickness 0.1 mm. It had a glass transition temperature (Tg) of 120 °C and a melting point (Tin) of 255 °C. PET was used in our devices as interposed lamina as well as a mask to produce multilayer films with an alternating thickness of approximately 0.1 mm. The two other components used for the multilayers were the following. Polycaprolactone (PCL) from Solvay; Tg -62 °C and T m 66 °C. With this polymer, and with PET, five-layer multistrates [6] (PET/PCL/PET/PCL/PET) were obtained by compression-moulding PCL within PET sheets at 110 °C and at a pressure of 100 kgcm -2, followed by. quenching to room temperature. Ethylene-vinyl acetate copolymer (EVA) from Dupont, a thermo

The structure of phases and interphases in samples crystallized under controlled undercoolings, of isotactic polypropylene/ethylene-co-propylene copolymers (iPP/EPR blends) was examined using optical and electron microscopy and small-angle X-ray scattering and differential scanning calorimetry. The study was undertaken to establish the influence of molecular structure of the EPR copolymers and blend composition on the phase structure developed in samples isothermally crystallized at relatively low undercoolings. Optical and electron microscopy revealed that the molecular structure and composition of the EPR phase play a predominant role in determining the mode and state of dispersion of the minor rubber component. It was also found that the crystallization process of iPP from its blends was influenced by the presence of the EPR phase with no regular dependence on its molecular structure and composition. For a given crystallization temperature, a decrease in thickness of the crystalline lamellae,Lc, and an increase in the amorphous interlamellar layer,La were observed. TheLc andLa values were found to be strictly related to the blend composition;Lc decreasing andLa increasing with increasing EPR content in the blend.

Polypropylene (PP) based blends containing as second non-crystallizable component commercial ethylene-propylene copolymers (EPR) having different C3 contents (wt/wt) and molecular-weight distributions (MWD), and, for fixed C3 content and MWD almost constant, different average molecular mass, were investigated. The study was undertaken to establish the influence of EPR molecular structure and composition on the melt rheology, on the mode and state of dispersion of the minor component in the melt as well as in the solid state and on the impact properties of injection-moulded samples. An attempt to correlate the molecular structure of EPR with rheological behaviour, size of rubbery particles and impact resistance was also accomplished. It was found that the values of the blend zero-shear viscosity (ηo) and the α(blend) parameter, obtained by applying the Cross equation, decrease with increasing dispersion coarseness of the minor component according to the results already obtained while studying the different incompatible blend system made by polyamide-6 and ethylene-vinyl acetate copolymers. The size and size distribution of EPR domains are determined by the value of the phase viscosity ratio (μ) irrespective of C3 content along the EPR chain. The trend of the number-average particle diameter ( D n ) versus log μ showed that D n decreases with decreasing log μ, in agreement with expectation on the basis of Taylor-Tomotika theory. The range of particle size effective for PP toughening was dependent on test temperature; for a temperature higher than EPR Tg and close to PP Tg, such range is narrower than that effective at room temperature.

To realize a system for textile design patterns retrieval, we adopt an Image Indexing Method-Based Region. This indexing method is achieved by regions segmentation process followed by regions indexing one. Note that the later indexing process strongly depends on the quality of produced segmentation, and will have a negative impact on retrieval results. Therefore, an efficient segmentation method must be developed. In this paper, we propose an adaptive and efficient unsupervised color image segmentation method. The proposed method is based on Gaussian Mixture Model, and cluster validity index. The model parameters are estimated using EM algorithm, and the optimal cluster number is detected by Cluster Validity Index. Using this method, the design patterns are well extracted. In the second part of this work, the outcome of this segmentation results will be supplied to the input of the indexing process to complete our retrieval system. © The Textile Institute 2006. ________________________________________

Two different diisocyanates were investigated as co-monomers for in situ polymerisation of poly(urethane-urea) into Neapolitan yellow tuff for conservation and restoration purpose. The obtained copolymers were characterised by means of FTIR spectroscopy, whereas the protective and consolidating efficiency of the performed treatments was evaluated through water capillary absorption, water vapour permeability and abrasion resistance measurements. The distribution and the penetration depth of the synthesized copolymer were also analysed applying micro-FTIR. The morphology of treated tuff was investigated by SEM. It was shown that comparatively higher protective and consolidating properties are achieved by using 1,6-diisocyanatohexane as monomer for in situ polymerisation.

The first synthesis of poly(urethane urea) by in situ polymerization inside stone was successfully carried out. Poly(propylene glycol), isophorondiisocyanate, and a catalyst [tin(II) ethyl hexanoate, aluminum acetylacetonate, or zirconium acetylacetonate] were mixed with acetone in petri dishes, and tuff samples were placed in the dishes at room temperature. The effects of the comonomer ratio, catalyst, and catalyst concentration on the chemical structure of the synthesized poly(urethane urea) were investigated. The poly(urethane urea) distribution inside the tuff and the related morphology were also analyzed, as well as the reversibility of the performed treatments. Finally, the effects of the in situ polymerization polymer on the properties of the stone, such as water capillary absorption and permeability to water vapor, were assessed.

In this paper, the problem of crossed-states detection is investigated and solved. The identification of the weave types in the fabric is realized by analyzing the texture information in the extracted crossed-points. This analysis is termed as 'crossed-states detection'. Finally, to evaluate visually our proposed method, it is applied to plain woven fabric without skewness as well as with skewness. The obtained results demonstrate the ability to solve such crossed-states detection problems. This non-destructive method will be a useful tool that can decrease the human intervention in analysing fabric weave types, especially in the context of ancient textiles.

Conductive polymer composites are important materials for many technical applications. These materials can be used as solar cells, resistors, semiconductor elements, antistatics and electromagnetic shielding materials [1-4]. In our previous publications we attempted to study the electrical characteristics of different polymer composites, at low and high frequency (microwave) range with respect to different types of fillers under different conditions [5-8]. The reported results indicate that the conductivity behaviour of carbon fibre filled polymer composites is governed by complex charge transfer mechanisms such as tunnelling, hopping and interconnecting between fibres. The rate of crosslinking depends on the fibre concentration and their distribution [9, 10]. However, there have been few investigations into the type of majority charge carriers that could be presented in the bulk. For example, it was thought that laminated carbon fibreepoxy composite is likely to exhibits interesting electrical properties. The present work is concerned with calculation of the charge carrier concentration in unidirectional epoxy-laminated carbon fibre composite using the Hall effect concept. We applied the Hall effect technique because it is controlled by surface states. We believe that this technique is practically suitable for materials that have conduction mechanism controlled by hopping or tunnelling processes. Furthermore, this technique was used successfully to measure the compliance of some orientated polymers [11]. The samples used in this study were epoxy composite containing 10, 25 and 36 layers of unidirectional carbon fibres. The prepreg epoxy resin was provided by DuPont (Italy). The physical parameters of this epoxy are given elsewhere [7]. The laminated sheet composites were prepared by embedding carbon fibre layers in epoxy matrix using curing hot pressing techniques. Samples in the form of parallelpipeds were cut from each composite sheet. The electrodes were made of copper evaporated on both sides of the specimen for Hall effect measurements. The measurements were performed at room temperature under constant magnetic field. A conventional Hall effect experimental set-up

With the aim of clarifying the complex shapes of the stress-strain curves of yams such as wool and silk and improving the reproducibility of the experimental results achieved through their mechanical characterization, nylon 6,6 yams consisting of one, three, nine, and thirty filaments are selected as a modeling system. Moreover, the uniaxial tensile properties of commercial nylon 6,6 yarns are investigated and compared with the corre sponding properties of commercial wool and silk yarns. Moisture level plays a very relevant role in determining the mechanical behavior of yarns. With an increasing moisture level of conditioning, in fact, nylon 6,6, wool, and silk yarns show neat breaking points, and their stress-strain curves tend to assume the typical shape of the curve shown by respective single fibres. This suggests that high moisture levels minimize the multiple breakage phenomena occurring in the yam. Moreover, for all the yarns investigated and, in particular, for wool, the process of conditioning at 100% RH reduces the variability of the experimental results, thus inducing a significant improvement in the precision and reproducibility of uniaxial tensile tests.

The use of pulsed laser radiation in order to remove small particles from a substrate has gained a growing interest in the last decade, finding applications in several fields ranging from the microcircuits industry to cultural heritage restoration and conservation. The application of such a technique requires the knowledge of the correct laser irradiation parameters to be used in order to obtain a desired result avoiding substrate damage. In this paper we have studied the effect of frequency-doubled (532 nm) Nd:YAG laser radiation on clean cotton samples. We have observed that ‘yellowing’ is present even at low fluences. This suggests that less invasive laser assisted particle removal techniques, some of which have already been proposed by different authors, must be considered.

Conversion of dihydroxyl groups to dialdehyde by periodate oxidation is a useful method widely used in derivatization of cellulose to activate the polymer to further reactions as grafting polymerization. To investigate the cellulose behavior at different level of oxidation and to better understand the influence of the crystallinity on the effects induced by oxidative reactions on different cellulose materials, linen and cotton textiles have been oxidized with periodate solutions in different conditions. Oxidized cellulose samples have been characterized by several techniques: solid-state 13 C NMR, Wide Angle X-Ray diffraction, and SEM. Moreover the mechanical properties of the untreated and oxidized yarns have been evaluated by means of tensile tests, the oxidation degree has been measured by means of the hydroxylamine hydrochloride method.

With the aim of better understanding the phenomena related to the application of polymeric materials on natural fiber textiles for restoration purposes, six commercial polymers based on acrylic and acetovinylic monomers are tested on modem cotton textiles. Cotton samples are impregnated with water dispersions of these polymers. The morphology of the polymeric films formed on the surfaces of the fibers, the chromatic and consolidating effects of the applications, and the adhesive properties of the polymers are investigated. The morphology of the films coating the fibers is independent of the morphology of the fibers constituting the textile substrate. There are no relevant chromatic effects related to the application of polymeric materials on cotton fabrics, indicating that treatments should be compatible with the aesthetic of cotton items. The consolidating effect of application is evaluated on cotton yarns artificially degraded in HCl solution, and depends strictly on the amount of polymer applied. Peel strength values exhibited by cotton samples prepared by compression molding and under vacuum suggest that the most useful adhesive agents are those with a Tg slightly lower than room temperature.

We evaluated the occurrence of a rapid process of restenosis after percutaneous mitral valvuloplasty (PMV), initiated by the recurrence of acute rheumatic fever. Restenosis after PMV has been mainly related to a high echocardiographic score (or = 8) indicating a severely compromised mitral valve apparatus.From 1986 to 1996, 120 patients underwent PMV by the transseptal approach at our Institution. The mean follow-up time was 58 +/- 32 months (range 3 months to 9 years).Restenosis occurred in 10 patients (8.3%): in 4 restenosis was found within a relatively short period of time (1 to 3 months) following a documented recurrence of acute rheumatic fever; in the other 6 patients there was a gradual loss of the initial gain in the mitral valve area.These data suggest two potential mechanisms of restenosis: 1) a more common slow process, due to turbulent flow-trauma on the mitral valve; 2) a rapid process that relates to valvulitis consequent to a recurrence of acute rheumatic fever. In consideration of the second possibility, after PMV prophylactic treatment may be warranted at least in those patients who are at high risk of streptococcal infection.

Woven coronary malformation is characterized by the branching of a major epicardial coronary artery into thin channels which then merge again in a normal conduit. The angiogram can suggest a filling defect instead of a malformation and an undue coronary angioplasty could be performed determining some damage to the arterial wall. In this case report we describe a patient with a stenosis on the left anterior descending coronary artery and a woven coronary artery on the right coronary artery. In 1995 a coronary angioplasty was performed on the left anterior descending coronary artery. Four years later a coronary angiogram did not show any changes in the right coronary artery. In this patient the malformation did not induce any reduction in the coronary reserve as shown at cardiac scintigraphy. We need more information about the natural history of such a malformation.

Plasma beta-endorphin levels were studied in the coronary sinus of 8 patients undergoing percutaneous transluminal coronary angioplasty (PTCA). All the patients had ECG ischemic signs and pain during the inflation of the balloon. No significant changes in plasma beta-endorphin levels were observed during PTCA-induced ischemia. Baseline coronary sinus plasma beta-endorphin levels were found to be elevated when compared with peripheral ones which would suggest an accumulation of beta-endorphin in the ischemic heart.

In this multicenter, randomized trial we evaluated whether stent implantation after successful recanalization of a chronic coronary occlusion reduced the incidence of restenosis.Percutaneous transluminal coronary angioplasty (PTCA) in chronic total occlusions is associated with a higher rate of angiographic restenosis and reocclusion than PTCA in subtotal stenoses. Preliminary reports have suggested a decreased restenosis rate after stent implantation in coronary total occlusions.We randomly assigned 110 patients with recanalized total occlusion to Palmaz-Schatz stent implantation, followed by 1 month of anticoagulant therapy versus no other treatment. The primary end point was the minimal lumen diameter (MLD) of the treated segment at follow-up, as determined by quantitative angiography at a core laboratory.Repeat coronary angiography was performed 9 months after the procedure in 88% of patients. The MLD (mean +/- SD) at follow-up was 1.74 +/- 0.88 mm in patients assigned to stent implantation and 0.85 +/- .75 mm in patients assigned to PTCA (p0.001). Stent implantation was associated with a lower incidence of restenosis (defined as diameter stenosisor =50% at follow-up) (32% vs. 68%, p0.001) and reocclusion (8% vs. 34%, p = 0.003) than balloon PTCA. Likewise, stent-treated patients had less recurrent ischemia (14% vs. 46%, p = 0.002) and target lesion revascularization (5.3% vs. 22%, p = 0.038), but experienced a longer hospital stay.Palmaz-Schatz stent implantation after successful balloon PTCA of chronic total occlusions improves the midterm angiographic and clinical outcome and could be the preferred treatment option in selected patients with occluded vessels.

The properties of a polymer can be extensively modified by physical mixing with another polymer. The properties of the resulting polymer blend depend not only on the composition and processing conditions but also on the physical state of each component at the temperature of application of the blend. Most of the theoretical and experimental investigations of the properties of polymer blends concern mainly systems containing amorphous components [1]. Recently, for both fundamental and practical reasons, blends with crystallizable components have received increasing attention [2].