In vitro effects of nonesterified fatty acids on bovine neutrophils oxidative burst and viability

An in vitro study was conducted to examine the influence of nonesterified fatty acids (NEFA) on bovine polymorphonuclear leukocytes (PMN). Eight healthy, midlactating Holstein cows were used as blood donors. Blood PMN were isolated and incubated with a mixture of NEFA, reflecting composition of bovine plasma NEFA at concentrations that were intended to mimic those found in blood of cows undergoing high, moderate, or low lipomobilization intensity (2, 1, 0.5, 0.25, 0.125, and 0.0625 mM). Control samples were incubated in absence of NEFA. Phagocytosis and oxidative burst activities were assessed by a 2-color flow cytometric method, which was based on oxidation of intracellular dihydrorhodamine 123 to green fluorescent rhodamine 123. Oxidative burst products were generated by incubating PMN with Staphylococcus aureus labeled with propidium iodide. A flow cytometric technique was used to detect PMN viability, necrosis, and apoptosis using fluorescein isothiocyanate-labeled annexin-V and propidium iodide. Phagocytic activity was not affected by NEFA. The highest concentration of NEFA (2 mM) was associated with a dramatic increase of phagocytosis-associated oxidative burst activities with a reduction in cell viability (48.0 vs. 97.5% in control samples) and with a marked increase of necrosis (49.4 vs. 0.5% in control samples). Conversely, the mixture of NEFA did not affect the occurrence of apoptosis. Enhancement of the oxidative burst associated with the highest concentration of NEFA might explain the reduced viability and higher percentage of necrosis observed under the same conditions. This study demonstrated a substantial resistance of bovine PMN to an overload of fatty acids. However, observation that the highest concentration of NEFA regulated some PMN functions encourages the possibility of in vivo studies to assess the relationships between intensity of lipomobilization, plasma NEFA, and bovine PMN functions

Patient-Specific Virtual Insertion of Electrode Array for Electrical Simulations of Cochlear Implants

International audienceSensorineural hearing loss is becoming one the most common reasons of disability. Worldwide 278 million people (around 25% of people above 45 years) suffer from moderate to several hearing disorders. Cochlear implantation (CI) enables to convert sound to an electrical signal that directly stimulates the auditory nerves via the electrode array surgically placed. However, this technique is intrinsically patient-dependent and its range of outcomes is very broad. A major source of outcome variability resides in the electrode array insertion. It has been reported to be one of the most important steps in cochlear implant surgery. In this context, we propose a method for patient-specific virtual electrode insertion further used into a finite element electrical simulation, and consequently improving the planning of the surgical implantation. The anatomical parameters involved in the electrode insertion such as the curvature and the number of turns of the cochlea, make virtual insertion highly challenging. Moreover, the influence of the insertion parameters and the use of different manufactured electrode arrays increase the range of scenarios to be considered for the implantation of a given patient. To this end, the method we propose is fast, easily parameterizable and applicable to a wide range of anatomies and insertion configurations. Our method is novel for targeting automatic virtual electrode insertion. Also, it combines high-resolution imaging techniques and clinical data to be further used into a finite element study and predict implantation outcomes in humans

Mécanismes immunopathologiques associés aux granulomes et kystes odontogènes: revue générale

The authors make a general survey of the immunopathological mechanisms involved in odontogenic cysts and granulomas. The dental pulp and the sound periapical tissues contain neither inflammatory nor immunoglobin-producing cells.Dental decay associated with bacterial agression of the dental pulp and periapical tissues might induce a non-specific inflammation which subsequently becomes more specific. Immunoglobulins are present in fluid aspirates from odontogenic cysts and granulomas.Several investigations have pointed out non-specific inflammatory mediators (including the C3 complement components), T lymphocytes (helpers and suppressors), B lymphocytes, Protein S-100 + cells (Langerhans cells).The presence of immunoglobulins, immunocompetent cells and C3 complement components confirms that all constituents of both humoral and cell-mediated immunological reactions might play an essential role in the pathogenesis of osteolysis.Les auteurs font une mise au point concernant les mécanismes immunopathologiques associés aux granulomes et kystes odontogènes.L’apparition de la carie dentaire suivie de l’agression des tissus pulpaires et périapicaux par les bactéries et leurs toxines pourrait induire une réponse inflammatoire non spécifique d’abord, puis spécifique ensuite.Les kystes odontogènes inflammatoires et ceux liés au développement, mais secondairemlent infectés, sont également le siège de réactions inflammatoires chroniques.On sait que les IgG, les IgA et les IgM sont présents dans le produit d’aspiration du kyste. Les IgE ont également été mises en évidence mais dans une moindre proportion.Plusieurs investigations rapportées dans la littérature ont mis en évidence dans les lésions kystiques et les granulomes dentaires:— les différents médiateurs non spécifiques de l’inflammation (y compris les produits dérivés de la fraction C3 du complémnt)— les lymphocytes T («helper» et «suppressor»)— les lymphocytes B— les cellules «protéine S-100 positives».La présence de toutes les classes d’immunoglobulines, de cellules immuno-compétentes et des produits dérivés de la fraction C3 du complément dans les kystes et granulomes dentaires pourrait expliquer la pathogénie des lésions d’ostéolyse qui les accompagnent

Automatic Generation of a Computational Model for Monopolar Stimulation of Cochlear Implants

International audienceCochlear implants have the potential to significantly improve severe sensorineural hearing loss. However, the outcome of this technique is highly variable and depends on patient-specific factors. We previously proposed a method for patient-specific electrical simulation after CI, which can assist in surgical planning of the CI and determination of the electrical stimulation pattern. However, the virtual implant placement and mesh generation were carried out manually and the process was not easily applied automatically for further cochlear anatomies. Moreover, in order to optimize the implant designs, it is important to develop a way to stimulate the results of the implantation in a population of virtual patients. In this work we propose an automatic framework for patient-specific electrical simulation in CI surgery. To the best of our knowledge, this is the first method proposed for patient-specific generation of hearing models which combines high-resolution imaging techniques, clinical CT data and virtual electrode insertion. Furthermore, we show that it is possible to use the computational models of virtual patients to simulate the results of the electrical activation of the implant in the cochlea and surrounding bone. This is an important step because it allows us to advance towards a complete surgical planning and implant optimization procedure

SPM to the heart: mapping of 4D continuous velocities for motion abnormality quantification

International audienceThis paper proposes to apply parallel transport and statistical atlas techniques to quantify 4D myocardial motion abnormalities. We take advantage of our previous work on cardiac motion , which provided a continuous spatiotemporal representation of velocities, to interpolate and reorient cardiac motion fields to an unbiased reference space. Abnormal motion is quantified using SPM analysis on the velocity fields, which includes a correction based on random field theory to compensate for the spatial smoothness of the velocity fields. This paper first introduces the imaging pipeline for constructing a continuous 4D velocity atlas. This atlas is then applied to quantify abnormal motion patterns in heart failure patients

Morphological changes in 15 skeletal muscles of horses after 8 weeks of aquatraining

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Prediction of infarct localization from myocardial deformation

International audienceWe propose a novel framework to predict the location of a myocardial infarct from local wall deformation data. Non-linear dimensionality reduction is used to estimate the Euclidean space of coordinates encoding deformation patterns. The infarct location of a new subject is inferred by two consecutive interpolations, formulated as multiscale kernel regressions. They consist in (i) finding the low-dimensional coordinates associated to the measured deformation pattern, and (ii) estimating the possible infarct location associated to these coordinates. These concepts were tested on a database of 500 synthetic cases generated from a realistic electromechanical model of the two ventricles. The database consisted of infarcts of random extent, shape, and location overlapping the whole left-anterior-descending coronary territory. We demonstrate that our method is accurate and significantly overcomes the limitations of the clinically-used thresholding of the deformation patterns (average area under the ROC curve of 0.992±0.011 vs. 0.812±0.124, p<0.001)

Removal of a below knee plaster cast worn for 28 months: a case report

<p>Abstract</p> <p>Introduction</p> <p>An unusual situation in which a below knee cast was removed after 28 months is reported. To the best of our knowledge no similar cases have been reported in the literature.</p> <p>Case presentation</p> <p>The cast was removed from the leg of a 45-year-old Caucasian woman. Significant muscle atrophy and dense skin scales were present but the underlying skin surface was relatively healthy with only small pitted 1-2 mm ulcers. No pathogenic organisms were cultured from this environment.</p> <p>Conclusion</p> <p>It seems likely that skin can tolerate cast immobilization for prolonged duration.</p

Histological type and marker expression of the primary tumour compared with its local recurrence after breast-conserving therapy for ductal carcinoma in situ

We have investigated primary ductal carcinomas in situ (DCIS) of the breast and their local recurrences after breast-conserving therapy (BCT) for histological characteristics and marker expression. Patients who were randomized in the EORTC trial 10853 (wide local excision versus excision plus radiotherapy) and who developed a local recurrence were identified. Histology was reviewed for 116 cases; oestrogen and progesterone receptor status, and HER2/ neu and p53 overexpression were assessed for 71 cases. Comparing the primary DCIS and the invasive or non-invasive recurrence, concordant histology was found in 62%, and identical marker expression in 63%. Although 11% of the recurrences developed at a distance from the primary DCIS, nearly all these showed the same histological and immunohistochemical profile. 5 patients developed well-differentiated DCIS or grade I invasive carcinoma after poorly differentiated DCIS. Although these recurrences occurred in the same quadrant as the primary DCIS, they may be considered as second primary tumours. Only 4 patients developed poorly differentiated DCIS or grade III invasive carcinoma after well differentiated DCIS. We conclude that in most cases the primary DCIS and its local recurrence are related histologically or by marker expression, suggesting that local recurrence usually reflects outgrowth of residual DCIS; progression of well differentiated DCIS towards poorly differentiated DCIS or grade III invasive carcinoma is a non-frequent event. © 2001 Cancer Research Campaign http://www.bjcancer.co