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https://www.readbyqxmd.com/read/28227821/dual-modality-arterial-pulse-monitoring-system-for-continuous-blood-pressure-measurement
#1
Wen-Xuan Dai, Yuan-Ting Zhang, Jing Liu, Xiao-Rong Ding, Ni Zhao, Wen-Xuan Dai, Yuan-Ting Zhang, Jing Liu, Xiao-Rong Ding, Ni Zhao, Wen-Xuan Dai, Yuan-Ting Zhang, Xiao-Rong Ding, Ni Zhao, Jing Liu
Accurate and ambulatory measurement of blood pressure (BP) is essential for efficient diagnosis, management and prevention of cardiovascular diseases (CVDs). However, traditional cuff-based BP measurement methods provide only intermittent BP readings and can cause discomfort with the occlusive cuff. Although pulse transit time (PTT) method is promising for cuffless and continuous BP measurement, its pervasive use is restricted by its limited accuracy and requirement of placing sensors on multiple body sites...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227451/cuff-pressure-induced-pat-changes-modelling-and-experimental-verification-towards-calibration-of-blood-pressure-surrogates
#2
Erik Bresch, Lars Schmitt, Dennis De Matteis, Jens Muehlsteff, Erik Bresch, Lars Schmitt, Dennis De Matteis, Jens Muehlsteff, Erik Bresch, Dennis De Matteis, Lars Schmitt, Jens Muehlsteff
Arterial Blood Pressure (ABP) is one of the most often measured vital parameters in daily clinical practice. State-of-the-Art non-invasive ABP measurement technologies have obvious limitations and are still mainly based on uncomfortable techniques by complete or partial occlusions of arteries. Additionally, embodiments are bulky, difficult to apply for the layman, or provide only intermittent measurements. We have been investigating the pulse arrival time (PAT) and pulse transit time (PTT) methodology for unobtrusive blood pressure (BP) measurements...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227450/using-multiple-placements-of-accelerometers-to-measure-cardiovascular-pulse-transit-times
#3
Natalie Kurgan Canino, Ruisheng Rick Wang, Charles J Robinson, Natalie Kurgan Canino, Ruisheng Wang, Charles J Robinson, Natalie Kurgan Canino, Charles J Robinson, Ruisheng Rick Wang
To measure pulse transit times (PTT) and calculate pulse wave velocities (PWV), tri-axial and uniaxial accelerometers were placed in groups of 2 to 4 over the manubrium, xiphoid process, forehead, wrist and ankle, and/or over the carotid, femoral, and posterior auricular arteries in 11 consented supine subjects. Signals were sampled at 1 kHz and filtered. Radial vectors were calculated from the tri-axial measurements. A 3-lead ECG was simultaneously collected over the same 180 s window, as well as respiratory rate...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227448/a-pulse-transit-time-based-fusion-method-for-the-noninvasive-and-continuous-monitoring-of-respiratory-rate
#4
Xiao-Rong Ding, Yuan-Ting Zhang, Hon Ki Tsang, Walter Karlen, Xiao-Rong Ding, Yuan-Ting Zhang, Hon Ki Tsang, Walter Karlen, Hon Ki Tsang, Walter Karlen, Yuan-Ting Zhang, Xiao-Rong Ding
The purpose of this study was to investigate whether pulse transit time (PTT) can be used for continuous monitoring of respiratory rate (RR). We derived PTT from the electrocardiogram and photoplethysmogram obtained from 42 recordings of CapnoBase, a publicly available benchmark data set for validating respiratory related measurements. The number of breaths in a minute (RR#) was estimated from the heart rate interval (HRI), pulse rate interval (PRI), and from PTT. In addition, to improve the estimation reliability, we investigated a fusion of the three HRI, PRI and PTT derived estimations...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227262/pulse-transit-time-and-heart-rate-variability-in-sleep-staging
#5
Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic, Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic, Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic
This paper presents a new and robust algorithm for detection of sleep stages by using the lead I of the Electrocardiography (ECG) and a fingertip Photoplethysmography (PPG) sensor, validated using multiple overnight PSG recordings consisting of 20 human subjects (9 insomniac and 11 healthy). Heart Rate Variability (HRV) and Pulse Transit Time (PTT) biomarkers which were extracted from ECG and PPG biosignals then employed to extract features. Distance Weighted k-Nearest Neighbours (DWk-NN) was used as classifier to differentiate sleep epochs...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227193/double-sensor-complementary-placement-method-to-reduce-motion-artifacts-in-ppg-using-fast-independent-component-analysis
#6
Frank P-W Lo, Max Q-H Meng, Frank P-W Lo, Max Q-H Meng, Max Q H Meng, Frank P W Lo
A novel sensor placement method for better removal of motion artifacts (MA) from photoplethysmography (PPG) signal using Fast Independent Component Analysis (ICA) is proposed in this paper. The method enhances the determination of pulse transit time (PTT) of PPG signals. The design makes use of double reflectance mode based PPG probes, which are placed complementary to each other and on the two sides of a single finger. Furthermore, a novel indicator denoted as Separating Factor is proposed as well. It helps evaluating the performance of ICA with different sensors configuration...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227114/photoplethysmography-derivatives-and-pulse-transit-time-in-overnight-blood-pressure-monitoring
#7
Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic, Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic, Sobhan Salari Shahrbabaki, Beena Ahmed, Thomas Penzel, Dean Cvetkovic
Overnight continuous blood pressure measurement provides simultaneous monitoring of blood pressure and sleep architecture. By this means, we are able to investigate whether different sleep events are associated to blood pressure fluctuations. In this paper, we used the Pulse Transit Time (PTT) to develop and evaluate functions for measurement of blood pressure. We focused on the first and second derivatives of fingertip Photoplethysmography (PPG) recordings to detect PPG critical points. By applying R wave of ECG and PPG critical points, we created two PTT-based models for estimation of systolic and diastolic blood pressure (SBP and DBP)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226573/a-preliminary-study-on-multi-wavelength-ppg-based-pulse-transit-time-detection-for-cuffless-blood-pressure-measurement
#8
Jing Liu, Yuan-Ting Zhang, Xiao-Rong Ding, Wen-Xuan Dai, Ni Zhao, Jing Liu, Yuan-Ting Zhang, Xiao-Rong Ding, Wen-Xuan Dai, Ni Zhao, Wen-Xuan Dai, Yuan-Ting Zhang, Xiao-Rong Ding, Ni Zhao, Jing Liu
Pulse transit time (PTT) has been widely studied as an index of blood pressure (BP) changes. In recent years, some prototypes of PTT-based wearable BP measurement devices have been developed, which can relieve users from the discomfort caused by the inflating cuff used in auscultatory and oscillometric BP measurement techniques. However, in the common practice for PTT detection, multi-site sensor implementation on human body is required, making it difficult for the integration of wearable devices. Since multi-wavelength (MW) photoplethysmogram (PPG) signals carry blood pulsation information of different blood vessels embedded in different skin depths, the time difference between different wavelength PPG signals collected at the same body site can be treated as a special PTT on a short length of blood vessels beneath the skin...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226571/cuff-less-ppg-based-continuous-blood-pressure-monitoring-a-smartphone-based-approach
#9
Aman Gaurav, Maram Maheedhar, Vijay N Tiwari, Rangavittal Narayanan, Aman Gaurav, Maram Maheedhar, Vijay N Tiwari, Rangavittal Narayanan, Maram Maheedhar, Rangavittal Narayanan, Vijay N Tiwari, Aman Gaurav
Cuff-less estimation of systolic (SBP) and diastolic (DBP) blood pressure is an efficient approach for non-invasive and continuous monitoring of an individual's vitals. Although pulse transit time (PTT) based approaches have been successful in estimating the systolic and diastolic blood pressures to a reasonable degree of accuracy, there is still scope for improvement in terms of accuracies. Moreover, PTT approach requires data from sensors placed at two different locations along with individual calibration of physiological parameters for deriving correct estimation of systolic and diastolic blood pressure (BP) and hence is not suitable for smartphone deployment...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28224106/impact-of-high-dose-vitamin-c-on-platelet-function
#10
Bassem M Mohammed, Kimberly W Sanford, Bernard J Fisher, Erika J Martin, Daniel Contaifer, Urszula Osinska Warncke, Dayanjan S Wijesinghe, Charles E Chalfant, Donald F Brophy, Alpha A Fowler Iii, Ramesh Natarajan
AIM: To examine the effect of high doses of vitamin C (VitC) on ex vivo human platelets (PLTs). METHODS: Platelet concentrates collected for therapeutic or prophylactic transfusions were exposed to: (1) normal saline (control); (2) 0.3 mmol/L VitC (Lo VitC); or (3) 3 mmol/L VitC (Hi VitC, final concentrations) and stored appropriately. The VitC additive was preservative-free buffered ascorbic acid in water, pH 5.5 to 7.0, adjusted with sodium bicarbonate and sodium hydroxide...
February 4, 2017: World Journal of Critical Care Medicine
https://www.readbyqxmd.com/read/28222636/change-in-pulse-transit-time-in-the-lower-extremity-after-lumbar-sympathetic-ganglion-block-an-early-indicator-of-successful-block
#11
Eun-Young Joo, Yu Gyeong Kong, Jonghyuk Lee, Hyun-Seok Cho, Sung-Hoon Kim, Jeong Hun Suh
Objective To investigate the change in pulse transit time (PTT)-time between the electrocardiographic R wave and the highest point of the corresponding plethysmographic wave-after lumbar sympathetic ganglion block (LSGB) and evaluate PTT as an indicator of successful LSGB. Methods Sixteen cases of sympathetically mediated lower extremity neuropathic pain treated with LSGB were studied. Correlations between the changes in PTT and temperature were used to identify the cutoff point indicating successful LSGB. Results PTT rate of change at 5 min relative to the baseline PTT (dPTT5/PTT0) significantly correlated positively with the temperature change at 20 min (correlation coefficient 0...
February 2017: Journal of International Medical Research
https://www.readbyqxmd.com/read/28218346/usefulness-of-clearance-parametric-images-in-detection-of-regional-renal-parenchyma-dysfunction
#12
Jacek Kuśmierek, Małgorzata Bieńkiewicz, Tomasz Konecki, Marian Surma, Marek Sosnowski, Anna Płachcińska
BACKGROUND: The aim of the study was to examine whether parametric clearance images (PAR) enhance diagnostic potential of a dynamic renal scintigraphy with detection of local dysfunction of kidneys, on a model of kidneys after treatment with extracorporeal shock wave lithotripsy (ESWL), MATERIAL AND METHODS: Kidneys after ESWL were accepted as a proper model for the implementation of this objective because of the previously proven damaging effect of a shock wave on renal parenchyma and known region of ESWL application...
2017: Nuclear Medicine Review. Central & Eastern Europe
https://www.readbyqxmd.com/read/28203580/unusual-presentation-of-diffuse-large-b-cell-lymphoma-with-splenic-infarcts
#13
Vivek Kumar, Parita Soni, Vishangi Dave, Jonathan Harris
A 67-year-old man presented with a 3-day history of abdominal pain, fever, and significant weight loss over 2 months. Physical examination revealed left upper quadrant tenderness, hepatomegaly, splenomegaly, and bilateral pitting edema but peripheral lymphadenopathy was absent. Laboratory tests showed anemia, thrombocytopenia, elevated prothrombin time (PT), partial thromboplastin time (PTT), and increased lactate dehydrogenase (LDH). PTT was corrected completely in mixing study. Further workup for the cause of coagulopathy revealed decreased levels of all clotting factors except factor VIII and increase fibrinogen levels, which ruled out disseminated intravascular coagulation (DIC)...
January 2017: Journal of Investigative Medicine High Impact Case Reports
https://www.readbyqxmd.com/read/28198716/incidence-of-cannula-associated-deep-vein-thrombosis-after-veno-venous-ecmo
#14
Jay Menaker, Ali Tabatabai, Raymond Rector, Katelyn Dolly, Joseph Kufera, Eugenia Lee, Zachary Kon, Pablo Sanchez, Si Pham, Daniel L Herr, Michael Mazzeffi, Ronald P Rabinowitz, James V OʼConnor, Deborah M Stein, Thomas M Scalea
Limited literature regarding the incidence of cannula associated deep vein thrombosis (CaDVT) following veno-venous extracorporeal membrane oxygenation (VV ECMO) exists. The purpose of this study was to identify the incidence of post decannulation CaDVT and identify any associated risk factors. Forty eight patients were admitted between August 2014 and January 2016 to the Lung Rescue Unit were included in the study. Protocolized anticoagulation levels (partial thromboplastin time 45-55 second) and routine post decannulation DVT screening were in place during the study period...
February 13, 2017: ASAIO Journal: a Peer-reviewed Journal of the American Society for Artificial Internal Organs
https://www.readbyqxmd.com/read/28192672/smart-nanostructures-for-cargo-delivery-uncaging-and-activating-by-light
#15
Mahdi Karimi, Parham Sahandi Zangabad, Soodeh Baghaee-Ravari, Mahdi Ghazizadeh, Hamed Mirshekari, Michael R Hamblin
Nanotechnology has begun to play a remarkable role in various fields of science and technology. In biomedical applications, nanoparticles have opened new horizons, especially for biosensing, targeted delivery of therapeutics, etc. Among drug delivery systems (DDSs), smart nanocarriers that can respond to specific stimuli in their local environment represent a growing field. Nanoplatforms that can be activated by an external application of light, can be used for a wide variety of photo-activated therapies, (especially light-triggered DDSs) relying on photo-isomerization, photo-crosslinking/uncrosslinking, photo-reduction, etc...
February 13, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28184979/association-between-hematologic-and-inflammatory-markers-and-31-thrombotic-and-hemorrhagic-events-in-berlin-heart-excor-patients
#16
Amit Iyengar, Matthew L Hung, Kian Asanad, Oh Jin Kwon, Nicholas J Jackson, Brian L Reemtsen, Myke D Federman, Reshma M Biniwale
Bleeding and thrombotic events remain a significant cause of morbidity in pediatric patients supported with ventricular assist devices (VADs). The objective of this study is to identify the association between markers of anticoagulation and bleeding and thrombosis events during Berlin Heart ExCor support. A retrospective, single-center analysis of 9 patients supported with the Berlin Heart ExCor was performed. Inflammatory and anticoagulation parameters including C-reactive protein, fibrinogen, partial thromboplastin time (PTT), and platelet count were measured at 48 and 24 h before and after bleeding or thrombosis events...
February 10, 2017: Pediatric Cardiology
https://www.readbyqxmd.com/read/28181456/dual-plasmonic-gold-nanostars-for-photoacoustic-imaging-and-photothermal-therapy
#17
Vijay Raghavan, Cathal O'Flatharta, Roisin Dwyer, Aedán Breathnach, Haroon Zafar, Peter Dockery, Antony Wheatley, Ivan Keogh, Martin Leahy, Malini Olivo
AIM: To fabricate multimodal nanoconstruct that act as a single node for photoacoustic imaging (PAI) and photothermal therapy (PTT) in the fight against cancer. MATERIALS & METHODS: Dual plasmonic gold nanostars (DPGNS) were chemically synthesized by reducing gold precursor using ascorbic acid and silver ions as shape directing agent. PAI and PTT were performed using commonly available 1064 nm laser source on DPGNS embedded tumor xenografts on mice. RESULTS & CONCLUSION: Photoacoustic amplitude increase with longer wavelength source and with silica coating of DPGNS...
February 9, 2017: Nanomedicine
https://www.readbyqxmd.com/read/28166774/highly-wearable-cuff-less-blood-pressure-and-heart-rate-monitoring-with-single-arm-electrocardiogram-and-photoplethysmogram-signals
#18
Qingxue Zhang, Dian Zhou, Xuan Zeng
BACKGROUND: Long-term continuous systolic blood pressure (SBP) and heart rate (HR) monitors are of tremendous value to medical (cardiovascular, circulatory and cerebrovascular management), wellness (emotional and stress tracking) and fitness (performance monitoring) applications, but face several major impediments, such as poor wearability, lack of widely accepted robust SBP models and insufficient proofing of the generalization ability of calibrated models. METHODS: This paper proposes a wearable cuff-less electrocardiography (ECG) and photoplethysmogram (PPG)-based SBP and HR monitoring system and many efforts are made focusing on above challenges...
February 6, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28165076/zwitterionic-gold-nanorods-low-toxicity-and-high-photothermal-efficacy-for-cancer-therapy
#19
Huangyong Jiang, Dong Chen, Dongbo Guo, Nan Wang, Yue Su, Xin Jin, Gangsheng Tong, Xinyuan Zhu
Novel "zwitterionic" gold nanorods (Au NRs) were constructed through a facile ligand exchange process between cetyltrimethylammonium bromide (CTAB)-Au NRs and the zwitterionic block polymer {poly(2-methacryloyloxyethyl phosohorylcholine)-b-poly(lipoic methacrylate) (pMPC-b-pLA)}. In vitro, they exhibited low dark cytotoxicity and a high therapeutic efficacy to cancer cells. Their blood circulation half-life in vivo (t1/2, ∼10 h) was 20-fold longer than that of CTAB-Au NRs (t1/2, <30 min). After intravenous administration, they accumulated in tumour sites via an enhanced permeability and retention (EPR) effect and enabled destruction of human xenograft tumours in mice after exposure of the tumour location to NIR laser irradiation at 808 nm...
February 6, 2017: Biomaterials Science
https://www.readbyqxmd.com/read/28161572/single-wavelength-light-mediated-synergistic-bimodal-cancer-photoablation-and-amplified-photothermal-performance-by-graphene-gold-nanostar-photosensitizer-theranostics
#20
Chunhui Wu, Dan Li, Lianhui Wang, Xiaotian Guan, Yuan Tian, Hong Yang, Shun Li, Yiyao Liu
: Light-triggered nanotheranostics opens a fascinating but challenging avenue to achieve simultaneous and highly efficient anticancer outcomes for multimodal therapeutic and diagnostic modalities. Herein, a multifunctional phototheranostics based on a photosensitizer-assembled graphene/gold nanostar hybrid (GO/AuNS-PEG) was developed for cancer synergistic photodynamic (PDT) and photothermal therapy (PTT) as well as effective photothermal imaging. The stable and biocompatible GO/AuNS-PEG composite displayed a high photothermal conversion efficiency due to the enhanced optical absorbance of both graphene and gold nanostars in the near-infrared (NIR) range...
February 1, 2017: Acta Biomaterialia
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