Search results for: blood pressure
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Study of Non-Newtonian biomagnetic blood flow in a stenosed bifurcated artery having elastic walls
PublicationFluid structure interaction (FSI) gained attention of researchers and scientist due to its applications in science felds like biomedical engineering, mechanical engineering etc. One of the major application in FSI is to study elastic wall behavior of stenotic arteries. In this paper we discussed an incompressible Non-Newtonian blood fow analysis in an elastic bifurcated artery. A magnetic feld is applied along x direction. For...
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New method to monitor changes in the subarachnoid width and pial artery pulsation for physiological and clinical research
PublicationThere are several medical conditions associated with brain oedema such as traumatic brain injury, intoxication or tumors. Brain edema and related brain parenchyma expansion may lead to compression and subsequent injury of several brain structures. So far, the only method enabling detection and monitoring of the progress a cerebral oedema in a patient, has been monitoring of intracranial pressure (ICP) with a pressure probe inserted...
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Pial artery and subarachnoid width response to apnoea in normal humans
PublicationBackground: Little is known about intracranial pressure (ICP)-cerebral haemodynamic interplay during repetitive apnoea. A recently developed method based on near-infrared transillumination/backscattering sounding (NIR-T/BSS) noninvasively measures changes in pial artery pulsation (cc-TQ) as well as subarachnoid width (sas-TQ) in humans. Method: We tested the complex response of the pial artery and subarachnoid width to apnoea...
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Effect of Maximal Apnoea Easy-Going and Struggle Phases on Subarachnoid Width and Pial Artery Pulsation in Elite Breath-Hold Divers
PublicationPurpose: The aim of the study was to assess changes in subarachnoid space width (sas-TQ), the marker of intracranial pressure (ICP), pial artery pulsation (cc-TQ) and cardiac contribution to blood pressure (BP), cerebral blood flow velocity (CBFV) and cc-TQ oscillations throughout the maximal breath hold in elite apnoea divers. Non-invasive assessment of sas-TQ and cc-TQ became possible due to recently developed method based on...
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Effects of consecutive apneas on pial artery pulsation and subarachnoid width in healthy subjects
PublicationHypercapnia is known to dilate the pial artery, disrupt cerebral autoregulation and increase pial artery pulsation. The cerebral blood flow velocity (CBFV) response to hypercapnia is biphasic. Below the threshold for the increase of blood pressure (BP) with carbon dioxide partial pressure (pCO2), the CBFV measurement reflects vascular reactivity to pCO2 alone at a constant BP. Above this threshold, the CBFV measurement provides...
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Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency
PublicationPial artery adjustments to changes in blood pressure (BP)may last only seconds in humans. Using a novelmethod called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of...
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Fatal N-Ethylhexedrone Intoxication
PublicationN-Ethylhexedrone [2-(ethyloamino)-1-phenylhexan-1-one; α-ethylaminohexanophenone; NEH] is one of the most recent synthetic cathinones that appeared on the illegal market in late 2015. The majority of information concerning the model of consumption of NEH and its impact on the body originates only from self-reports from grey literature websites and drug forums. There are only limited data associated with the concentrations of NEH...
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Numerical Model of the Aortic Valve Implanted Within Real Human Aorta
PublicationCardiovascular system diseases are the main cause of deaths in developed and developing countries. The main reasons are myocardial infarction, heart failure, stroke and valvular diseases. These are caused mainly by arteriosclerosis. The valvular diseases involve a significant burden for the health care system and their frequency is rising with the patient age. This work describes the tools and numerical models appropriate for modeling...
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CARDIOVASCULAR RISK FACTORS AMONG POLISH EMPLOYEES OF UNIFORMED SERVICES
PublicationObjectives: Employees of uniformed services (EoUS) were screened for cardiovascular risk factors. Material and Methods: A total of 1138 EoUS (age M±SD 49.9±6.0 years) and 263 controls (age M±SD 54.4±9.7 years) under the care of the cardiology clinic in Gdańsk, Poland,were included in the study. Medical history and blood samples were collected, and a physical examination was performed. Ten-year cardiovascular risk of death was...
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Human subarachnoid space width oscillations in the resting state
PublicationAbnormal cerebrospinal fluid (CSF) pulsatility has been implicated in patients suffering from various diseases, including multiple sclerosis and hypertension. CSF pulsatility results in subarachnoid space (SAS) width changes, which can be measured with near-infrared transillumination backscattering sounding (NIR-T/BSS). The aim of this study was to combine NIR-T/BSS and wavelet analysis methods to characterise the dynamics of the...
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Mild poikilocapnic hypoxia increases very low frequency haemoglobin oxygenation oscillations in prefrontal cortex
PublicationBackground: The aim of the study was to investigate the effect of mild cerebral hypoxia on haemoglobin oxygenation(HbO2), cerebrospinal fluid dynamics and cardiovascular physiology. To achieve this goal, four signals were recorded simultaneously: blood pressure, heart rate / electrocardiogram, HbO2 from right hemisphere and changes of subarachnoid space (SAS) width from left hemisphere. Signals were registered from 30 healthy,...
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Comparison of near infrared spectroscopy (NIRS) and near-infrared transillumination-backscattering sounding (NIR-T/BSS) methods
PublicationThe aim of the study was to compare simultaneously recorded a NIR-T/BSS and NIRS signals from healthy volunteers. NIR-T/BSS is a device which give an ability to non-invasively detect and monitor changes in the subarachnoid space width (SAS). Experiments were performed on a group of 30 healthy volunteers (28 males and 2 females, age 30.8 ± 13.4 years, BMI = 24.5 ± 2.3 kg/m2). We analysed recorded signals using analysis methods based...
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Innovative Implantable Left Ventricular Assist Device—Performance under Various Resistances and Operating Frequency Conditions
PublicationThis paper presents the operation of an innovative left ventricular assist device under various resistances and operating frequencies. The operating principle of the device is based on pulsatile blood flow, which is forced by a suction–discharge device pumping helium into a set of intra-cardiac balloons. In this way, the ejection fraction of the left ventricle is increased, and the mitral valve is additionally occluded. What is...
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Fluid structure interaction study of non-Newtonian Casson fluid in a bifurcated channel having stenosis with elastic walls
PublicationFluid–structure interaction (FSI) gained a huge attention of scientists and researchers due to its applications in biomedical and mechanical engineering. One of the most important applications of FSI is to study the elastic wall behavior of stenotic arteries. Blood is the suspension of various cells characterized by shear thinning, yield stress, and viscoelastic qualities that can be assessed by using non-Newtonian models. In this...
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The non-invasive evaluation of heart function in patients with an acute myocardial infarction: The role of impedance cardiography
PublicationBackground: The purpose of this study was to analyze hemodynamic changes in patients treated with percutaneous coronary intervention (PCI) at an early stage of acute myocardial infarction (AMI) and at one-month follow-up. Methods: Patients with AMI (n = 27) who underwent PCI were analyzed using impedance cardiography (ICG). ICG data were collected continuously (beat by beat) during the whole PCI procedure and thereafter at every...
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Computer-Aided Detection of Hypertensive Retinopathy Using Depth-Wise Separable CNN
PublicationHypertensive retinopathy (HR) is a retinal disorder, linked to high blood pressure. The incidence of HR-eye illness is directly related to the severity and duration of hypertension. It is critical to identify and analyze HR at an early stage to avoid blindness. There are presently only a few computer-aided systems (CADx) designed to recognize HR. Instead, those systems concentrated on collecting features from many retinopathy-related...
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Blood equivalent phantom vs whole human blood, a comparative study
PublicationPreclinical research of biomedical optoelectronic devices is often performed with the use of blood phantoms — a simpli¯ed physical model of blood. The aim of this study is the comparison and distinction between blood phantoms as well as whole human blood measurements. We show how the use of such phantoms may in°uence the incorrect interpretation of measured signal. On the other hand, we highlight how the use of blood phantoms enables...
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MACHINE LEARNING SYSTEM FOR AUTOMATED BLOOD SMEAR ANALYSIS
PublicationIn this paper the authors propose a decision support system for automatic blood smear analysis based on microscopic images. The images are pre-processed in order to remove irrelevant elements and to enhance the most important ones - the healthy blood cells (erythrocytes) and the pathologic (echinocytes). The separated blood cells are analyzed in terms of their most important features by the eigenfaces method. The features are the...
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Applications of Raman spectroscopy for detection of selected substances in tissues
PublicationThis dissertation explores the applications of Raman spectroscopy for biological tissue analysis. Basics of Raman and surface-enhanced Raman spectroscopy (SERS) are described, along with an analysis of the literature on biodetection and non-invasive blood analysis with emphasis on glucose detection. Instrumentation for Raman measurements is described. The sources of noise and interferences occurring in biological tissue measurements...
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Computed aided system for separation and classification of the abnormal erythrocytes in human blood
PublicationThe human peripheral blood consists of cells (red cells, white cells, and platelets) suspended in plasma. In the following research the team assessed an influence of nanodiamond particles on blood elements over various periods of time. The material used in the study consisted of samples taken from ten healthy humans of various age, different blood types and both sexes. The markings were leaded by adding to the blood unmodified...
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Between autonomy and paternalism: Attitudes of nursing personnel towards Jehovah’s Witnesses’ refusal of blood transfusion
PublicationObjectives: The study describes the attitudes of Polish nursing personnel towards Jehovah’s Witnesses’ (JWs’) refusal to receive blood and blood products.Methods: We developed an online survey assessing nurses’ knowledge and attitudes towards JWs’ refusal of blood transfusion in a life-threatening condition. It also examined nurses’ attitudes towards ethical and legal issues associated with JWs’ refusal of bloodtransfusions....
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Measurement of complex refractive index of human blood by low-coherence interferometry
PublicationIn this article, the usefulness of the optical technique for measurements of blood complex refractive index has been examined. Measurement of optical properties of human blood is difficult to perform because of its nonuniform nature. However, results of my investigation have shown the usefulness of low-coherencei nterferometry for measurement complex refractive index of human blood. Furthermore, mathematical analysis of spectrum...
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The gaseous messenger carbon monoxide is released from the eye into the ophthalmic venous blood depending on the intensity of sunlight
PublicationCircadian and seasonal rhythms in daylight affect many physiological processes. In the eye, energy of intense visible light not only initiates a well-studied neural reaction in the retina that modulates the secretory function of the hypothalamus and pineal gland, but also activates the heme oxygenase (HO) to produce carbon monoxide (CO). This study was designed to determine whether the concentration of carbon monoxide (CO) in the...
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Raman spectroscopic investigation of blood and related materials
PublicationThis paper reports preliminary studies on use of Raman spectroscopy for investigation of blood. High quality blood spectra were recorded in-vitro with excitation wavelengths of 830 nm. Because of complex composition of the blood as well as by light attenuation and scattering in the tissues, spectra set up from wide, low-intensive Raman bands and intensive optical background. To get information about origin of bands in Raman spectra...
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Comment on "Quantitative comparison of analysis methods for spectroscopic optical coherence tomography"
PublicationIn a recent paper by Bosschaart et al. [Biomed. Opt. Express 4, 2570 (2013)] various algorithms of time-frequency signal analysis have been tested for their performance in blood analysis with spectroscopic optical coherence tomography sOCT). The measurement of hemoglobin concentration and oxygen saturation based on blood absorption spectra have been considered. Short time Fourier transform (STFT) was found as the best method for...
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Initial Report on Numerical Modeling of Blood Flow in Myocardial Bridge Region of Coronary Artery: Concept of Model Validation
PublicationThe paper presents a numerical method of blood flow simulation within the coronary artery covered by the myocardial bridge. The myocardial bridge is a congenital coronary abnormality caused by the blood vessel location under one of the heart muscles. In this case, the blood flow within the vessel is partially disturbed which can cause several consequences. The presented numerical simulation allowed us to estimate the blood flow...
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A review of methods of blood supply to organs of the gastrointestinal tract. State of art
PublicationThe correct assessment of blood supply is essential to eliminate possible postoperative complications. Re-anastomosis of the gastrointestinal tract after its resection must be preceded by the analysis of blood supply to the anastomosed fragments. It is important that the blood supply assessment procedure is reliable but also non-absorbing and, if possible, short. It should also be possible to repeat the procedure due to the need...
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A SHORT REVIEW OF BLOOD FLOW MODELLING METHODS: FROM MACRO- TO MICROSCALES
PublicationThe aim of this paper it to review various scale approaches to the blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic descriptions. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented with particular attention...
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Absorption spectroscopy setup for determination of whole human blood and blood–derived materials spectral characteristics
PublicationA dedicated absorption spectroscopy system was set up using tungsten-halogen broadband source, optical fibers, sample holder, and a commercial spectrometer with CCD array. Analysis of noise present in the setup was carried out. Data processing was applied to the absorption spectra to reduce spectral noise, and improve the quality of the spectra and to remove the baseline level. The absorption spectra were measured for whole blood...
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Sensing of anesthetic drugs in blood with Raman spectroscopy
PublicationA proof-of-concept study of a Raman spectroscopy-based approach for measuring the content of anesthesia drugs in blood is presented. Spectra of spiked blood from several patients exhibit prominent changes in regions associated with the drug.
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Combined analysis of whole human blood parameters by Raman spectroscopy and spectral-domain low-coherence interferometry
PublicationIn this article the simultaneous investigation of blood parameters by complementary optical methods, Raman spectroscopy and spectral-domain low-coherence interferometry, is presented. Thus, the mutual relationship between chemical and physical properties may be investigated, because low-coherence interferometry measures optical properties of the investigated object, while Raman spectroscopy gives information about its molecular...
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Haemocompatibility of Modified Nanodiamonds
PublicationThis study reports the interactions of modified nanodiamond particles in vitro with human blood. Modifications performed on the nanodiamond particles include oxygenation with a chemical method and hydrogenation upon chemical vapor deposition (CVD) plasma treatment. Such nanodiamonds were later incubated in whole human blood for different time intervals, ranging from 5 min to 5 h. The morphology of red blood cells was assessed along...
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Sensors for Rapid Detection of Environmental Toxicity in Blood of Poisoned People
PublicationRecently, the diagnosis and treatment of poisoned person can be done only in specialized centers. Furthermore, currently used clinical methods of intoxication diagnosis are not sufficient for early detection. Conventional laboratory tests based on urine and blood require professional, high skilled staff, high cost equipment as well as they are arduous and lasting analytical procedures. There is a need to elaborate relatively cheap...
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Utilizing pulse dynamics for non-invasive Raman spectroscopy of blood analytes
PublicationNon-invasive measurement methods offer great benefits in the field of medical diagnostics with molecular-specific techniques such as Raman spectroscopy which is increasingly being used for quantitative measurements of tissue biochemistry in vivo. However, some important challenges still remain for label-free optical spectroscopy to be incorporated into the clinical laboratory for routine testing. In particular, non-analyte-specific...
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Modelling of blood flow: from macro to microscales
PublicationThe aim of this paper it to review various scale approaches to blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic description. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented.
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Optoelectronic device for hematocrit measurements
PublicationAn optoelectronic system for measurements of hematocrit level (HCT) in the whole human blood is presented. Proposed system integrates a dedicated optoelectronic sensor, a microcontroller and a small LCD display in a low cost, battery-powered, handheld device. Chosen method for determining blood hematocrit level is based on optical properties of whole blood in visible and NIR wavelength range. Measurements with the use of proposed...
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Label‐free optical detection of cyclosporine in biological fluids
PublicationIn this paper, a spectroscopic method for determination of cyclosporine concentrations in biological fluids is presented. Blood plasma and hemoglobin solutions are chosen for the experiment. For various cyclosporine concentrations in blood plasma and hemoglobin, absorbance measurements in spectra range from 600 to 1100 nm are performed. The measurement results are analyzed by the use of a dedicated algorithm. The obtained data...
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Application of spectroscopy to the measurement of blood parameters
PublicationSpectroscopy is the study of formation and interpretation of the spectra arising from the interactions of all types of radiation on matter, understood as a collection of atoms and molecules. This is a very important department of optics which gives us many opportunities to measure various parameters such as material blood parameters. Among the diseases that are associated significantly with changes in rheological properties of...
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On various modelling approaches to real-time visualisation of blood flow
PublicationThis paper reviews various modelling approaches to real-time visualisation of blood flow. These include classic, macroscale approach based on the momentum conservation equation together with a proper constitutive equation. Moreover, modern micro- and mesoscale approaches, such as molecular dynamics and dissipative particle dynamics, are discussed. Advantages and disadvantages of the discussed methods are highlighted with particular...
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Contour Analysis of Bleeding Regions in Endoscopic Images
PublicationThis paper investigates the problem of detecting bleeding regions in images acquired from endoscopic examinations of gastrointestinal tract. The purpose is to identify the characteristic features of bleeding areas' contours in order to develop an accurate method for discriminating between true bleeding regions and missed detections, which could lead to a significant reduction of the false alarm rate of existing blood-detection...
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Modeling and simulation of blood flow under the influence of radioactive materials having slip with MHD and nonlinear mixed convection
PublicationRadioactive materials are widely in industry, nuclear plants and medical treatments. Scientists and workers in these fields are mostly exposed to such materials, and adverse effects on blood and temperature profiles are observed. In this regard, objective of the current study is to model and simulate blood based nanofluid with three very important radioactive materials, named as Uranium dioxide (UO2), Thorium dioxide (ThO2) and...
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DIFFRACTION PHASE MICROSCOPY FOR OBSERVATION ON RED BLOOD CELLS FLUCTUATION
PublicationNowadays there is quite huge need for more and more precise and effective fast diagnostics methods in hematology diseases. One of the most important blood components are erythrocytes – RBCs (Red Blood Cells). Due to their size they are easy to observe using microscopy. It is commonly known that the shape and lifetime of RBCs allows for early disease identification. Authors present special measurement system for RBCs fluctuations observation...
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Active dynamic thermography method for TRAM flap blood perfusion mapping in breast reconstruction
PublicationThis paper presents the new method of the transverse rectus abdominis musculocutaneous flap blood perfusion mapping based on the active dynamic thermography. The method is aimed at aiding a surgeon during breast reconstruction procedure. A pair of dTnorm and t90_10 parameters were used as parametric image descriptors of the flap blood perfusion. The method was tested on 38 patients that were subjected to breast reconstruction procedure....
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Observation on red blood cells fluctuations by diffraction phase microscopy
PublicationNowadays there is quite huge need for more and more precise and effective fast diagnostics methods in hematology diseases. One of the most important blood components are erythrocytes – Red Blood Cells (RBCs). Due to their size they are easy to observe using microscopy. It is commonly known that the shape and lifetime of RBCs allows for early disease identification. Authors present special measurement system for RBCs fluctuations...
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Novel methods for diagnosis of pulmonary microangiopathy in diabetes mellitus
PublicationLung microangiopathy is a little known negative influence of diabetes mellitus on the functioning of the lungs. In current medical practice lung microangiopathy is diagnosed by comparing two measurements of lung diffusing capacity - one with the subject standing and one with the subject lying. The necessity to take two measurements is inconvenient. In lung microangiopathy we observe a reduction of diffusing capacity, lung flow...
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Obrazowanie perfuzji mózgu z wykorzystaniem modelowania parametrycznego danych DSC-MRI
PublicationPomiary DSC-MRI (Dynamic Susceptibility Contrast Magnetic Resonance Imaging) zostały wykorzystane w pracy do estymacji parametrów perfuzji mózgu: przepływu krwi mózgowej (cerebral blood flow, CBF), objętości krwi mózgowej (cerebral blood volume, CBV) oraz średniego czasu przejścia (mean transit time, MTT). Zaproponowano model trzykompartmentowy. Przedstawiono i porównano dwa podejścia do identyfikacji modelu na podstawie danych...
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Brain perfusion imaging with the use of parametric modelling basing on DSC-MRI data
PublicationW pracy do estymacji parametrów perfuzji mózgu: przepływu krwi mózgowej (cerebral blood flow, CBF), objętości krwi mózgowej (cerebral blood volume, CBV) oraz średniego czasu przejścia (mean transit time, MTT) wykorzystano pomiary DSC-MRI (Dynamic Susceptibility Contrast Magnetic Resonance Imaging). W modelowaniu danych MRI zastoswoano model trzykompartmentowy. Przedstawiono i porównano dwa podejścia do identyfikacji modelu różniące...
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Optoelectronic investigation of nanodiamond interactions with human blood
PublicationWe present optoelectronic investigation of in vitro interactions of whole human blood with different nanodiamond biomarkers. Plasmo-chemical modifications of detonation nanodiamond particles gives the possibility for controlling their surface for biological applications. Optical investigations reveal the biological activity of nanodiamonds in blood dependent on its surface termination. We compare different types of nanodiamonds:...
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Role of quantitative chest perfusion computed tomography in detecting diabetic pulmonary microangiopathy
PublicationAims: Aimof the study was to determine the role of perfusion chest computed tomography(pCT) in evaluation of pulmonary diabetic angiopathy.Methods: 18 never-smoking patients (10 diabetic patients and 8 healthy controls) underwentchest high resolution CT (HRCT) and then pCT scanning. In both groups, blood tests,biochemical analysis, fibrinogen, HbA1c, spirometry, diffusion capacity for carbonmonoxide(DLCO) and body pletysmography...
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Detection of propofol concentrations in blood by Raman spectroscopy
PublicationIn this paper we present a proof-of-concept of a Raman spectroscopy-based approach for measuring the content of propofol, a common anesthesia drug, in whole human blood, and plasma, which is intended for use during clinical procedures. This method utilizes the Raman spectroscopy as a chemically–sensitive method for qualitative detection of the presence of a drug and a quantitative determination of its concentration. A number of...