Search results for "DOPPLER"
showing 10 items of 637 documents
Invitation to participate in a multi-center study for validation of cerebral computed tomography angiography and computed tomography perfusion in the…
2021
In recent years commensal microorganisms are not just “passive occupants”, but important element of homeostasis. There are numerous reports documenting the composition and role of the gut, skin or vagina microbiome but the role of commensal organisms living in the lungs is relatively unknown. Pulmonary microbiome impact on the immune response of the host organism and may indicate new therapeutic directions. Lung microbiome, by modulating the expression of innate immunity genes, causes an increase in the concentration of IL-5, IL-10, IFNγ and CCL11, affects the TLR4 dependent response of pulmonary macrophages and modulate the production of antibacterial peptides contained in the mucus. It is…
MitoKATP-channel opener protects against neuronal death in rat venous ischemia.
2005
OBJECTIVE: Mitochondrial adenosine triphosphate-dependent potassium (mitoK ATP ) channels are present in the brain, and several reports have shown their neuroprotective, preconditioning effect against an ischemic insult. The role of mitoK ATP channels in the penumbra area has not been studied thoroughly. In a model of venous ischemia, widespread penumbra-like low flow areas are created, which are susceptible to cortical spreading depression. Thus, we studied effects of mitoK ATP channels on infarct size in this model. METHODS: Male Wistar rats were subjected to two-vein occlusion by photochemical thrombosis of two adjacent cortical veins combined with KCI-induced cortical spreading depressi…
The large-scale magnetic field of the eccentric pre-main-sequence binary system V1878 Ori
2020
We report time-resolved, high-resolution optical spectropolarimetric observations of the young double-lined spectroscopic binary V1878 Ori. Our observations were collected with the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope through the BinaMIcS large programme. V1878 Ori A and B are partially convective intermediate mass weak-line T Tauri stars on an eccentric and asynchronous orbit. We also acquired X-ray observations at periastron and outside periastron. Using the least-squares deconvolution technique (LSD) to combine information from many spectral lines, we clearly detected circular polarization signals in both components throughout the orbit. We refined the orbita…
Searching for the right timing of surgical delay: angiogenesis, vascular endothelial growth factor and perfusion changes in a skin-flap model.
2009
Summary Background The angiogenic potential of vascular endothelial growth factor (VEGF) and its oxygen pressure-dependent regulation suggest a strong connection between this growth factor and the ‘delay phenomenon'. In this study we focused on the chronological changes in VEGF concentration and flap perfusion in order to optimise the duration of surgical delay. Methods The VEGF concentration in skin and underlying muscle was measured in oversized, random-pattern flaps on 38 male Sprague-Dawley rats after 3, 5 or 7 days of surgical delay. Additionally, flaps were raised 5 or 7 days past preconditioning. The effect on flap perfusion was measured using indocyanine green fluoroscopy and the si…
LASCA and PPG imaging for non-contact assessment of skin blood supply
2013
Laser speckle contrast analysis (LASCA) offers a non-contact, full-field, and real-time mapping of capillary blood flow and can be considered as an alternative method to Laser Doppler perfusion imaging (LDPI). Photoplethysmography (PPG) is well known technique for assessment of skin blood pulsations that can be related to blood flow. In recent years several studies have been done on development of non-contact PPG imaging (PPGI). LASCA and PPGI techniques are simpler and cheaper compared with LDPI. LASCA technique has been implemented in several commercial instruments. However, these systems are still too expensive and bulky to be widely available. Several optical techniques have found new i…
Laboratory Measurements of Flow and Turbulence in Discontinuous Distributions of Ligulate Seagrass
2007
Turbulent flow characteristics were investigated in laboratory flume studies of a ligulate plant canopy interrupted by a gap representing discontinuities observed in seagrass prairies. The reliability of velocity measurements obtained using an acoustic Doppler velocimeter within the canopy was shown using specifically designed experiments. In relatively fast flow (mean velocity 5.5 cm s−1), the mean flow profile was logarithmic above the canopy, had an inflection point near its top, and uniformly low values within it. Within the gap, a recirculation cell formed. Reynolds stress maxima were approximately coincident with the mean flow inflection point. Quadrant analysis revealed an ejection-d…
The automated assesment of artery hemodynamic parameters from ultrasound video
2012
The custom designed video processing software for analysis of B-mode and Doppler-mode ultrasound video has been proposed in this work. The software allows adjusting user-defined thresholds and tolerance levels to enhance contour detection in noisy and artifacted ultrasound images. The developed software is able to evaluate 16 hemodynamic parameters (artery diameter, pulse rate and flow velocity related parameters) in each cardiac cycle. The measurements were performed intermittently recording artery diameter (B-mode) and flow velocity (Doppler-mode). Software has validated in femoral artery measurements. The hemodynamic parameters computed by software were consistent with those obtained by …
Chemotherapy cardiotoxicity: cardioprotective drugs and early identification of cardiac dysfunction.
2016
Background: Chemotherapy cardiotoxicity is an emerging problem and it is very important to prevent cardiac dysfunction caused by anticancer drugs. The aim of this study was to assess the alterations of the cardiac function induced by chemotherapy in a follow-up of 2 years and to evaluate the cardioprotective role of angiotensin-converting enzyme inhibitors (ACEIs) in the prevention of cardiac dysfunction. Methods: A prospective study was carried out using patients with breast cancer (85 women; median age 57W12years) and other inclusion and exclusion criteria. On the basis of treatment, patients were divided into six groups: fluorouracil-epirubicincyclophosphamide, FEC (group A); FEC and tra…
Cardiovascular imaging in the diagnosis and monitoring of cardiotoxicity: Role of echocardiography
2016
The evaluation by cardiovascular imaging of chemotherapy patients became a central topic in the last several years. The use of drugs for the treatment of cancers increased, and new molecules and protocols were developed to improve outcomes in these patients. Although, these novel approaches also produced a progressive increase in side effects, particularly myocardial dysfunction. Imaging of the heart was highly accurate in the early diagnosis of cancer therapeutics related-cardiac dysfunction. Echocardiography is the first-line method to assess ventricular function alterations, and it is required to satisfy the need for an early, easy and accurate diagnosis to stratify the risk of heart fai…
Chemotherapy-induced cardiotoxicity: role of the tissue Doppler in the early diagnosis of left ventricular dysfunction.
2011
Cardiotoxicity is a common complication of chemotherapy. The aim of this study was to assess the cardiotoxicity of anticancer drugs using tissue Doppler imaging. A prospective study was carried out using patients with early breast cancer (72 women, median age: 57 ± 12 year) and other inclusion and exclusion criteria. Inclusion criteria were treatment with epirubicin, trastuzumab, fluorouracil, cyclophosphamide, taxotere, and taxolo; left ventricular ejection fraction (LVEF) of more than 50%; and absence of important pathologies. Exclusion criteria were presence of known heart disease, earlier exposure to mediastinal irradiation, and earlier chemotherapy. On the basis of treatment, patients …