984 resultados para TIBIAL VESSEL OCCLUSIONS
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A possible relationship between C.pneumoniae (CP) infection, atherosclerosis and acute myocardial infarction is a debated matter. Now we performed the search of CP in histological segments of fatal ruptured plaques and of stable plaques by histochemistry (Macchiavello stain), immunohistochemistry and in situ hybridization techniques. Electron microscopy and confocal laser microscopy techniques were used in two additional cases. The semi-quantitification of CP + cells (0-4+) and quantification of lymphocytes demonstrated greater amount of CP + cells and more inflammation in the adventitia of vulnerable plaque vessel segments than of stable ones, larger amount of CP + cells in adventitia than in the plaque and high frequency of CP + cells in all groups studied. This preliminary study strongly suggests a direct pathogenetic involvement of adventitial CP in the rupture of the atheromatous plaque, development of acute myocardial infarction and also in the development of atherosclerosis.
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OBJECTIVE: To assess the in-hospital results and clinical follow-up of young patients (< 50 years) with multivessel coronary artery disease undergoing stent implantation in native coronary arteries and to compare their results with those of patients with single-vessel coronary artery disease. METHODS: We retrospectively studied 462 patients undergoing coronary stent implantation. Patients were divided into 2 groups: group I (G-I) - 388 (84%) patients with single-vessel coronary artery disease; and group II (G-II) - 74 (16%) patients with multivessel coronary artery disease. RESULTS: The mean age of the patients was 45±4.9 years, and the clinical findings at presentation and demographic data were similar in both groups. The rate of clinical success was 95% in G-I and 95.8% in G-II (P=0.96), with no difference in regard to in-hospital evolution between the groups. Death, acute myocardial infarction, and the need for myocardial revascularization during clinical follow-up occurred in 10.1% and 11.2% (P=0.92) in G-I and G-II, respectively. By the end of 24 months, the actuarial analysis showed an event-free survival of 84.6 % in G-I and 81.1% in G-II (P=0.57). CONCLUSION: Percutaneous treatment with coronary stent implantation in young patients with multivessel disease may be safe with a high rate of clinical success, a low incidence of in-hospital complications, and a favorable evolution in clinical follow-up.
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The lymphatic vasculature is important for the regulation of tissue fluid homeostasis, immune response, and lipid absorption, and the development of in vitro models should allow for a better understanding of the mechanisms regulating lymphatic vascular growth, repair, and function. Here we report isolation and characterization of lymphatic endothelial cells from human intestine and show that intestinal lymphatic endothelial cells have a related but distinct gene expression profile from human dermal lymphatic endothelial cells. Furthermore, we identify liprin beta1, a member of the family of LAR transmembrane tyrosine phosphatase-interacting proteins, as highly expressed in intestinal lymphatic endothelial cells in vitro and lymphatic vasculature in vivo, and show that it plays an important role in the maintenance of lymphatic vessel integrity in Xenopus tadpoles.
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All patients having undergone a coronarography during 1984 have been surveyed in Switzerland. This retrospective study has used existing data in the 13 centers practicing this diagnostic procedure. 4921 coronarographies were carried out in 1984, amongst 4359 patients. In terms of population-based rates, the national figures are 77 procedures/100,000 residents, and 68 patients/100,000 residents. Female rates are one fourth of the male rates (27/100,000 versus 112/100,000). For both sexes, the highest utilization rates are for the age groups 60-64. Swiss figures are relatively low when compared with other developed countries. However, patterns of utilization are very different within the country: according to the Canton of residence of the patient, the utilization rates (standardized for age and sex) vary from 8/100,000 to 160/100,000. There is a distinct gradient from south-west to north-east, which closely corresponds to the distribution of centers practicing the procedure. More intriguing is the fact that cardiovascular mortality shows an inverse geographical gradient, with the highest mortality in Cantons having the lowest rate of coronarography. Various reasons for the observed variations are discussed, in relation with differences in supply of diagnostic and therapeutic equipments, but also in relation with various patterns of demand related to differential morbidity rates and/or differential patterns of clinical decision.
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Objective: Saphenous vein graft bypass remains the salvage option when¦endovascular procedure has failed or was contraindicated due to extensive¦occlusive lesions. However, pathological wall remodeling leading leading to¦graft failure is one of the most limiting factors of this therapy. Therefore, the¦understanding of this remodeling process of human vein is essential to the design¦of future effective therapeutics and it requires an adapted model of ex-vivo vein¦perfusion.¦Methods: We have developed an ex vivo vein support system (EVVSS), which¦uses standardized and controlled hemodynamic parameters for the pulsatile¦perfusion of saphenous vein segments. The morphological and molecular¦parameters involved in the remodeling process under an arterial shear stress¦associated to low (7 mm Hg) or high (70 mm Hg) pressure conditions can be¦analyzed.¦Results: Histomorphometric analysis showed that the vein segments perfused¦during 7 days under high pressure undergo a significant neointima development¦compared to veins exposed to low pressure conditions. The application of an¦arterial shear stress in the vein under low pressure induced an elevation of the¦MMP-2 and MMP-9 expression, activity and transcription. The application of¦higher pressure is associated to increased MMP2 expression and transcription¦and MMP9 transcription. TIMP1 expression and transcription were initiated by¦the application of an arterial shear stress but not modified by the modification¦of the pressure. However, TIMP2 expression was increased under high¦pressure conditions but its transcription was inhibited by arterial shear stress,¦independently of the pressure. The values of transcription and expression of¦PAI-1 were not modified by high pressure. Eph-B4 transcription and expression¦were significantly decreased under arterial shear stress.¦Conclusion: These data show that our EVVSS is a valuable setting to study¦ex vivo remodeling of human saphenous veins submitted to arterial conditions.¦The intimal hyperplasia as well as MMP 2, 9 and TIMP 2 seem to be influenced¦by the pressure.
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BACKGROUND: Dissection during laparoscopic surgery produces smoke containing potentially toxic substances. The aim of the present study was to analyze smoke samples produced during laparoscopic colon surgery using a bipolar vessel sealing device (LigaSuretrade mark). METHODS: Four consecutive patients undergoing left-sided colectomy were enrolled in this pilot study. Smoke was produced by the use of LigaSuretrade mark. Samples (5,5l) were evacuated from the pneumoperitoneum in a closed system into a reservoir. Analysis was performed with CO2-laser-based photoacoustic spectroscopy and confirmed by a Fourier-transform infrared spectrum. The detected spectra were compared to the available spectra of known toxins. RESULTS: Samples from four laparoscopic sigmoid resections were analyzed. No relevant differences were noted regarding patient and operation characteristics. The gas samples were stable over time proven by congruent control measurements as late as 24 h after sampling. The absorption spectra differed considerably between the patients. One broad absorption line at 100 ppm indicating H2O and several unknown molecules were detected. With a sensitivity of alpha min ca 10-5 cm-1 no known toxic substances like phenol or indole were identified. CONCLUSION: The use of a vessel sealing device during laparoscopic surgery does not produce known toxic substances in relevant quantity. Further studies are needed to identify unknown molecules and to analyze gas emission under various conditions.
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In this study we analyzed the microanatomy of the dorsal vessel of the triatomine Panstrongylus megistus. The organ is a tuble anatomically divided into an anterior aorta anad a posterior heart, connected to the body wall through 8 pairs of alary muscles. The heart is divided in 3 chambers by means of 2 pairs of cardiac valves. a pair of ostia can be observed in the lateral wall of each chamber. A bundle of nerve fibers was found outside the organ, running dorsally along its major axis. A group of longitudinal muscular fibers was found in the ventral portion of the vessel. The vessel was found to be lined both internally and externally by pericardial cells covered by a thin laminar membrane. Inseide the vessel the pericardial cells were disposed in layers and on the outside they formed clusters or rows.
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Water transport in wood is vital for the survival of trees. With synchrotron radiation X-ray tomographic microscopy (SRXTM), it has become possible to characterize and quantify the three-dimensional (3D) network formed by vessels that are responsible for longitudinal transport. In the present study, the spatial size dependence of vessels and the organization inside single growth rings in terms of vessel-induced porosity was studied by SRXTM. Network characteristics, such as connectivity, were deduced by digital image analysis from the processed tomographic data and related to known complex network topologies.
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Coronary magnetic resonance angiography (MRA) is a technique aimed at establishing a noninvasive test for the assessment of significant coronary stenoses. There are certain boundary conditions that have hampered the clinical success of coronary MRA and coronary vessel wall imaging. Recent advances in hardware and software allow for consistent visualization of the proximal and mid portions of the native coronary arteries. Current research focuses on the use of intravascular MR contrast agents and black blood coronary angiography. One common goal is to create a noninvasive test which might allow for screening for major proximal and mid coronary artery disease. These novel approaches will represent a major step forward in diagnostic cardiology.
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Purpose. We evaluated the influence of the time between low-dose gadolinium (Gd) contrast administration and coronary vessel wall enhancement (LGE) detected by 3T magnetic resonance imaging (MRI) in healthy subjects and patients with coronary artery disease (CAD). Materials and Methods. Four healthy subjects (4 men, mean age 29 ± 3 years and eleven CAD patients (6 women, mean age 61 ± 10 years) were studied on a commercial 3.0 Tesla (T) whole-body MR imaging system (Achieva 3.0 T; Philips, Best, The Netherlands). T1-weighted inversion-recovery coronary magnetic resonance imaging (MRI) was repeated up to 75 minutes after administration of low-dose Gadolinium (Gd) (0.1 mmol/kg Gd-DTPA). Results. LGE was seen in none of the healthy subjects, however in all of the CAD patients. In CAD patients, fifty-six of 62 (90.3%) segments showed LGE of the coronary artery vessel wall at time-interval 1 after contrast. At time-interval 2, 34 of 42 (81.0%) and at time-interval 3, 29 of 39 evaluable segments (74.4%) were enhanced. Conclusion. In this work, we demonstrate LGE of the coronary artery vessel wall using 3.0 T MRI after a single, low-dose Gd contrast injection in CAD patients but not in healthy subjects. In the majority of the evaluated coronary segments in CAD patients, LGE of the coronary vessel wall was already detectable 30-45 minutes after administration of the contrast agent.
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SUMMARY: In a randomly selected cohort of Swiss community-dwelling elderly women prospectively followed up for 2.8 +/- 0.6 years, clinical fractures were assessed twice yearly. Bone mineral density (BMD) measured at tibial diaphysis (T-DIA) and tibial epiphysis (T-EPI) using dual-energy X-ray absorptiometry (DXA) was shown to be a valid alternative to lumbar spine or hip BMD in predicting fractures. INTRODUCTION: A study was carried out to determine whether BMD measurement at the distal tibia sites of T-EPI and T-DIA is predictive of clinical fracture risk. METHODS: In a predefined representative cohort of Swiss community-dwelling elderly women aged 70-80 years included in the prospective, multi-centre Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture risk (SEMOF) study, fracture risk profile was assessed and BMD measured at the lumbar spine (LS), hip (HIP) and tibia (T-DIA and T-EPI) using DXA. Thereafter, clinical fractures were reported in a bi-yearly questionnaire. RESULTS: During 1,786 women-years of follow-up, 68 clinical fragility fractures occurred in 61 women. Older age and previous fracture were identified as risk factors for the present fractures. A decrease of 1 standard deviation in BMD values yielded a 1.5-fold (HIP) to 1.8-fold (T-EPI) significant increase in clinical fragility fracture hazard ratio (adjusted for age and previous fracture). All measured sites had comparable performance for fracture prediction (area under the curve range from 0.63 [LS] to 0.68 [T-EPI]). CONCLUSION: Fracture risk prediction with BMD measurements at T-DIA and T-EPI is a valid alternative to BMD measurements at LS or HIP for patients in whom these sites cannot be accessed for clinical, technical or practical reasons.
Enclavado endomedular tibial: ¿Logra la vía de abordaje suprapatelar la misma reducción radiológica?
Resumo:
El tractament definitiu de les fractures tibials motiva diversos punts de controvèrsia. La via d'abordatge suprapatelar en posició de semiextensió, per al enclavat endomedul.lar tibial anterógrad, es va dissenyar amb l'objectiu principal d'evitar complicacions de l'abordatge tradicional trans o paratendó rotulià, com són la reducció de les fractures diafisàries proximals tibials i reduir el dolor anterior de genoll. Aquest nou abordatge quirúrgic, descrit al 2009, a més ha d'oferir uns resultats postoperatoris radiològics iguals o millors a la via d'abordatge tradicional. En aquest treball, s'ha descrit l'alineació radiològica postoperatòria, d'una sèrie de pacients afectes de fractura diafisaria tibial, tractats mitjançant abordatge suprapatelar i enclavat endomedul.lar a l'Hospital Vall d'Hebron.