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Sample records for non-invasive cardiac stress

  1. Non-invasive Mapping of Cardiac Arrhythmias.

    PubMed

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome).

  2. Non-invasive assessment of cardiac output in children.

    PubMed Central

    Richardson, J R; Ferguson, J; Hiscox, J; Rawles, J

    1998-01-01

    BACKGROUND: Stroke distance, the systolic velocity integral of aortic blood flow, is a linear analogue of stroke volume; its product with heart rate is minute distance, analogous to cardiac output. OBJECTIVE: To investigate the feasibility of assessing cardiac output in children with a simple non-invasive Doppler ultrasound technique, and to determine the normal range of values. METHODS: Peak aortic blood velocity, stroke distance, and minute distance were measured through the suprasternal window in 166 children (mean age 9.6 years, range 2-14) using a portable non-imaging Doppler ultrasound instrument. RESULTS: The technique was well tolerated by all the children participating. Mean peak aortic blood velocity was 138 cm/s and was independent of age. Mean stroke distance was 31.8 cm and showed a small but significant increase with age; mean minute distance was 2490 cm and fell with age, as did heart rate. CONCLUSIONS: Suprasternal Doppler ultrasound measurement of stroke distance is a convenient, well tolerated, non-invasive technique for the assessment of cardiac output in children. The normal range of values during childhood has been established. The technique has great potential for assessing hypovolaemia in children. Images p307-a PMID:9785155

  3. Stress detection in bivalve mollusk using non-invasive bioelectric monitoring of myoneural behavior

    SciTech Connect

    Morgan, E.L.; Hardison, B.S.; Dawson, V.K.; Waller, D.; Waller, W.T.; Dickson, K.L.; Allen, H.J.

    1995-12-31

    Few studies have demonstrated cause-and-effect linkages between extrinsic environmental factors and intrinsic bioelectric action potentials of bivalve mollusk using non-invasive, non-destructive approaches. A non-invasive, external probe configuration and detection system, similar to one used previously with native unionids, was developed for continuously monitoring bioelectric activities of clams and mussels. Using remote probes and differential amplifiers, bioelectric activities were recorded for cardiac, adductor, siphon and foot responses using a computer equipped with integrating software. To test if remote, non-invasive probes would detect similar information to that recorded by invasive needle electrodes, two individuals of zebra mussel (Dreissenia polymorpha), and Asiatic clam (Corbicula fluminea) were each configured with two sets of probes. One set was inserted between the valves and along the inside surface of the shelf; the other set was positioned remotely about the outside margins of the valves. Signal validation was made by simultaneously recording bioelectric responses for the same animal from both sets of probes. In preliminary stress tests monitored bivalves were subjected to changes in temperatures over 2 to 3 hr intervals from ambient to potentially lethal levels (20 to 30 C for zebra, 25 C to 40 C for corbicula). Dramatic increases resulted in both number and amplitude of cardiac events as temperature increased. Planned studies will use this approach to evaluate bivalve myoneural behavior patterns in response to chemical and non-chemical stimuli.

  4. Non-invasive assessment of cardiac output during mechanical ventilation - a novel approach using an inert gas rebreathing method.

    PubMed

    Nickl, Werner; Bugaj, Till; Mondritzki, Thomas; Kuhlebrock, Kathrin; Dinh, Winfried; Krahn, Thomas; Sohler, Florian; Truebel, Hubert

    2011-06-01

    Measurement of cardiac output (CO) is of importance in the diagnostic of critically ill patients. The invasive approach of thermodilution (TD) via pulmonary artery catheter is clinically widely used. A new non-invasive technique of inert gas rebreathing (IGR) shows a good correlation with TD measurements in spontaneously breathing individuals. For the first time, we investigated whether IGR can also be applied to sedated and mechanically ventilated subjects with a clinical point of care device. CO data from IGR were compared with TD in six healthy mongrel dogs. Data sampling was repeated under baseline conditions (rest) and under stress challenge by applying 10 μg/kg/min of dobutamine intravenously. Switching from mechanical ventilation to IGR, as well as the rebreathing procedures, were carried out manually. Cardiac output data from IGR and TD correlated with a coefficient of r=0.90 (95% confidence interval [0.81; 0.95]). The Bland-Altman analysis showed a bias of 0.46 l/min for the IGR CO measurements. Ninety-five percent of all differences fall in the interval [-1.03; 1.95], being the limit of the ± 1.96 standard deviation lines. IGR is a new approach for non-invasive cardiac output measurement in mechanically ventilated individuals, but requires further investigation for clinical use.

  5. Non-invasive cardiac imaging techniques and vascular tools for the assessment of cardiovascular disease in type 2 diabetes mellitus.

    PubMed

    Djaberi, R; Beishuizen, E D; Pereira, A M; Rabelink, T J; Smit, J W; Tamsma, J T; Huisman, M V; Jukema, J W

    2008-09-01

    Cardiovascular disease is the major cause of mortality in type 2 diabetes mellitus. The criteria for the selection of those asymptomatic patients with type 2 diabetes who should undergo cardiac screening and the therapeutic consequences of screening remain controversial. Non-invasive techniques as markers of atherosclerosis and myocardial ischaemia may aid risk stratification and the implementation of tailored therapy for the patient with type 2 diabetes. In the present article we review the literature on the implementation of non-invasive vascular tools and cardiac imaging techniques in this patient group. The value of these techniques as endpoints in clinical trials and as risk estimators in asymptomatic diabetic patients is discussed. Carotid intima-media thickness, arterial stiffness and flow-mediated dilation are abnormal long before the onset of type 2 diabetes. These vascular tools are therefore most likely to be useful for the identification of 'at risk' patients during the early stages of atherosclerotic disease. The additional value of these tools in risk stratification and tailored therapy in type 2 diabetes remains to be proven. Cardiac imaging techniques are more justified in individuals with a strong clinical suspicion of advanced coronary heart disease (CHD). Asymptomatic myocardial ischaemia can be detected by stress echocardiography and myocardial perfusion imaging. The more recently developed non-invasive multi-slice computed tomography angiography is recommended for exclusion of CHD, and can therefore be used to screen asymptomatic patients with type 2 diabetes, but has the associated disadvantages of high radiation exposure and costs. Therefore, we propose an algorithm for the screening of asymptomatic diabetic patients, the first step of which consists of coronary artery calcium score assessment and exercise ECG.

  6. [Non-invasive cardiac output measurement with USCOM in air rescue operation].

    PubMed

    Schedler, O; Handschak, H; Hensel, M

    2008-12-01

    In cardiac emergency events (NACA score = 3.4), a non-invasive cardiac output test involving transaortalic blood flow velocity measurement was used in the air rescue of 30 patients. An average velocity integral (Vti) of 21.9 +/- 9.9 cm was determined in the short examination time (t = 120 +/- 30 sec). Related to the middle body surface (BSA = 2.0 +/- 0.3 m (2)), the calculated cardiac index (CI) was 2.6 +/- 1.1 l/min/m (2). The CI was under 2.2 l/min/m (2) in 12 examinations (40 %). 5 patients in this group subsequently received catecholamine therapy. Thrombolysis therapy increased by 17 % in the myocardial infarction group with CI

  7. Electro-resistive bands for non-invasive cardiac and respiration monitoring, a feasibility study.

    PubMed

    Gargiulo, Gaetano D; O'Loughlin, Aiden; Breen, Paul P

    2015-02-01

    Continuous unobtrusive monitoring of tidal volume, particularly for critical care patients (i.e. neonates and patients in intensive care) during sleep studies and during daily activities, is still an unresolved monitoring need. Also a successful monitoring solution is yet to be proposed for continuous non-invasive cardiac stroke volume monitoring that is a novel clinical need.In this paper we present the feasibility study for a wearable, non-invasive, non-contact and unobtrusive sensor (embedded in a standard T-shirt) based on four electro-resistive bands that simultaneously monitors tidal volume and cardiac stroke volume changes. This low power sensor system (requires only 100 mW and accepts a wide power supply range up to ±18 V); thus the sensor can be easily embedded in existing wearable solutions (i.e. Holter monitors). Moreover, being contactless, it can be worn over bandages or electrodes, and as it does not rely over the integrity of the garment to work, it allows practitioners to perform procedures during monitoring. For this preliminary evaluation, one subject has worn the sensor over the period of 24 h (removing it only to shower); the accuracy of the tidal volume tested against a portable spirometer reported a precision of ±10% also during physical activity; accuracy tests for cardiac output (as it may require invasive procedure) have not been carried out in this preliminary trial.

  8. Patient-specific volume conductor modeling for non-invasive imaging of cardiac electrophysiology.

    PubMed

    Pfeifer, B; Hanser, F; Seger, M; Fischer, G; Modre-Osprian, R; Tilg, B

    2008-01-01

    We propose a general workflow to numerically estimate the spread of electrical excitation in the patients' hearts. To this end, a semi-automatic segmentation pipeline for extracting the volume conductor model of structurally normal hearts is presented. The cardiac electrical source imaging technique aims to provide information about the spread of electrical excitation in order to assist the cardiologist in developing strategies for the treatment of cardiac arrhythmias. The volume conductor models of eight patients were extracted from cine-gated short-axis magnetic resonance imaging (MRI) data. The non-invasive estimation of electrical excitation was compared with the CARTO maps. The development of a volume conductor modeling pipeline for constructing a patient-specific volume conductor model in a fast and accurate way is one essential step to make the technique clinically applicable.

  9. Non-invasive reproductive and stress endocrinology in amphibian conservation physiology

    PubMed Central

    Narayan, E. J.

    2013-01-01

    Non-invasive endocrinology utilizes non-invasive biological samples (such as faeces, urine, hair, aquatic media, and saliva) for the quantification of hormones in wildlife. Urinary-based enzyme immunoassay (EIA) and radio-immunoassay have enabled the rapid quantification of reproductive and stress hormones in amphibians (Anura: Amphibia). With minimal disturbance, these methods can be used to assess the ovarian and testicular endocrine functions as well as physiological stress in captive and free-living populations. Non-invasive endocrine monitoring has therefore greatly advanced our knowledge of the functioning of the stress endocrine system (the hypothalamo–pituitary–interrenal axis) and the reproductive endocrine system (the hypothalamo–pituitary–gonadal axis) in the amphibian physiological stress response, reproductive ecology, health and welfare, and survival. Biological (physiological) validation is necessary for obtaining the excretory lag time of hormone metabolites. Urinary-based EIA for the major reproductive hormones, estradiol and progesterone in females and testosterone in males, can be used to track the reproductive hormone profiles in relationship to reproductive behaviour and environmental data in free-living anurans. Urinary-based corticosterone metabolite EIA can be used to assess the sublethal impacts of biological stressors (such as invasive species and pathogenic diseases) as well as anthropogenic induced environmental stressors (e.g. extreme temperatures) on free-living populations. Non-invasive endocrine methods can also assist in the diagnosis of success or failure of captive breeding programmes by measuring the longitudinal patterns of changes in reproductive hormones and corticosterone within captive anurans and comparing the endocrine profiles with health records and reproductive behaviour. This review paper focuses on the reproductive and the stress endocrinology of anurans and demonstrates the uses of non-invasive endocrinology

  10. Non-invasive cardiac mapping in clinical practice: Application to the ablation of cardiac arrhythmias.

    PubMed

    Dubois, Rémi; Shah, Ashok J; Hocini, Mélèze; Denis, Arnaud; Derval, Nicolas; Cochet, Hubert; Sacher, Frédéric; Bear, Laura; Duchateau, Josselin; Jais, Pierre; Haissaguerre, Michel

    2015-01-01

    Ten years ago, electrocardiographic imaging (ECGI) started to demonstrate its efficiency in clinical settings. The initial application to localize focal ventricular arrhythmias such as ventricular premature beats was probably the easiest to challenge and validates the concept. Our clinical experience in using this non-invasive mapping technique to identify the sources of electrical disorders and guide catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats) and ventricular pre-excitation (Wolff-Parkinson-White syndrome) is described here.

  11. Non-invasive cardiac pacing with image-guided focused ultrasound

    PubMed Central

    Marquet, Fabrice; Bour, Pierre; Vaillant, Fanny; Amraoui, Sana; Dubois, Rémi; Ritter, Philippe; Haïssaguerre, Michel; Hocini, Mélèze; Bernus, Olivier; Quesson, Bruno

    2016-01-01

    Currently, no non-invasive cardiac pacing device acceptable for prolonged use in conscious patients exists. High Intensity Focused Ultrasound (HIFU) can be used to perform remote pacing using reversibility of electromechanical coupling of cardiomyocytes. Here we described an extracorporeal cardiac stimulation device and study its efficacy and safety. We conducted experiments ex vivo and in vivo in a large animal model (pig) to evaluate clinical potential of such a technique. The stimulation threshold was determined in 10 different ex vivo hearts and different clinically relevant electrical effects such as consecutive stimulations of different heart chambers with a single ultrasonic probe, continuous pacing or the inducibility of ventricular tachycardia were shown. Using ultrasonic contrast agent, consistent cardiac stimulation was achievable in vivo for up to 1 hour sessions in 4 different animals. No damage was observed in inversion-recovery MR sequences performed in vivo in the 4 animals. Histological analysis revealed no differences between stimulated and control regions, for all ex vivo and in vivo cases. PMID:27827415

  12. Non-invasive cardiac pacing with image-guided focused ultrasound

    NASA Astrophysics Data System (ADS)

    Marquet, Fabrice; Bour, Pierre; Vaillant, Fanny; Amraoui, Sana; Dubois, Rémi; Ritter, Philippe; Haïssaguerre, Michel; Hocini, Mélèze; Bernus, Olivier; Quesson, Bruno

    2016-11-01

    Currently, no non-invasive cardiac pacing device acceptable for prolonged use in conscious patients exists. High Intensity Focused Ultrasound (HIFU) can be used to perform remote pacing using reversibility of electromechanical coupling of cardiomyocytes. Here we described an extracorporeal cardiac stimulation device and study its efficacy and safety. We conducted experiments ex vivo and in vivo in a large animal model (pig) to evaluate clinical potential of such a technique. The stimulation threshold was determined in 10 different ex vivo hearts and different clinically relevant electrical effects such as consecutive stimulations of different heart chambers with a single ultrasonic probe, continuous pacing or the inducibility of ventricular tachycardia were shown. Using ultrasonic contrast agent, consistent cardiac stimulation was achievable in vivo for up to 1 hour sessions in 4 different animals. No damage was observed in inversion-recovery MR sequences performed in vivo in the 4 animals. Histological analysis revealed no differences between stimulated and control regions, for all ex vivo and in vivo cases.

  13. Peripartum cardiomyopathy: postpartum decompensation and use of non-invasive cardiac output monitoring.

    PubMed

    Lorello, G; Cubillos, J; McDonald, M; Balki, M

    2014-02-01

    The utility of a non-invasive cardiac output monitor (NICOM™) in guiding the peripartum management and identification of postpartum complications in a patient with severe peripartum cardiomyopathy is reported. A 31-year-old nulliparous woman at 35 weeks of gestation presented with a three-week history of worsening dyspnea and progressive functional deterioration. A transthoracic echocardiogram showed severe left ventricular systolic dysfunction with an ejection fraction <20%. Cardiac status was monitored using NICOM™ during labor and delivery. The baseline values were: cardiac output 5.3 L/min, total peripheral resistance 1549 dynes.sec/cm(5), stroke volume 42.1 mL and stroke volume variation 18%. She received early epidural analgesia during labor, titrated slowly with a loading dose of 0.0625% bupivacaine 10 mL and fentanyl 25 μg, followed by patient-controlled epidural analgesia (0.0625% bupivacaine with fentanyl 2 μg/mL, infusion at 10 mL/h, bolus dose 5 mL and lockout interval 10 min). After epidural drug administration, total peripheral resistance decreased, cardiac output increased, and satisfactory analgesia was obtained. She had an uneventful vaginal delivery with a forceps-assisted second stage after prophylactic administration of furosemide 20 mg. NICOM™ was discontinued after delivery. Fifteen hours post-delivery, the patient developed cardiogenic shock, which resolved after aggressive therapy with inotropes and furosemide. NICOM™ can be used to guide treatment during labor and delivery in patients with critical peripartum cardiomyopathy. We suggest that use of NICOM™ be extended into the postpartum period to detect signs of cardiac decompensation in such patients.

  14. Non-invasive cortisol measurements as indicators of physiological stress responses in guinea pigs

    PubMed Central

    Pschernig, Elisabeth; Wallner, Bernard; Millesi, Eva

    2016-01-01

    Non-invasive measurements of glucocorticoid (GC) concentrations, including cortisol and corticosterone, serve as reliable indicators of adrenocortical activities and physiological stress loads in a variety of species. As an alternative to invasive analyses based on plasma, GC concentrations in saliva still represent single-point-of-time measurements, suitable for studying short-term or acute stress responses, whereas fecal GC metabolites (FGMs) reflect overall stress loads and stress responses after a species-specific time frame in the long-term. In our study species, the domestic guinea pig, GC measurements are commonly used to indicate stress responses to different environmental conditions, but the biological relevance of non-invasive measurements is widely unknown. We therefore established an experimental protocol based on the animals’ natural stress responses to different environmental conditions and compared GC levels in plasma, saliva, and fecal samples during non-stressful social isolations and stressful two-hour social confrontations with unfamiliar individuals. Plasma and saliva cortisol concentrations were significantly increased directly after the social confrontations, and plasma and saliva cortisol levels were strongly correlated. This demonstrates a high biological relevance of GC measurements in saliva. FGM levels measured 20 h afterwards, representing the reported mean gut passage time based on physiological validations, revealed that the overall stress load was not affected by the confrontations, but also no relations to plasma cortisol levels were detected. We therefore measured FGMs in two-hour intervals for 24 h after another social confrontation and detected significantly increased levels after four to twelve hours, reaching peak concentrations already after six hours. Our findings confirm that non-invasive GC measurements in guinea pigs are highly biologically relevant in indicating physiological stress responses compared to circulating

  15. Quantification of the impaired cardiac output response to exercise in heart failure: application of a non-invasive device.

    PubMed

    Myers, Jonathan; Gujja, Pradeep; Neelagaru, Suresh; Hsu, Leon; Burkhoff, Daniel

    2009-01-01

    An impaired cardiac output (CO) response to exercise is a hallmark of chronic heart failure (CHF), and the degree to which CO is impaired is related to the severity of CHF and prognosis. However, practical methods for obtaining cardiac output during exercise are lacking, and what constitutes and impaired response is unclear. Forty six CHF patients and 13 normal subjects underwent cardiopulmonary exercise testing (CPX) while CO and other hemodynamic measurements at rest and during exercise were obtained using a novel, non-invasive, bioreactance device based on assessment of relative phase shifts of electric currents injected across the thorax, heart rate and ventricular ejection time. An abnormal cardiac output response to exercise was defined as achieving ≤ 95% of the confidence limits of the slope of the relationship between CO and oxygen uptake (VO2). An impaired CO slope identified patients with more severe CHF as evidenced by a lower peak VO2, lower peak CO, heightened VE/VCO2 slope, and lower oxygen uptake efficiency slope. CO can be estimated during exercise using a novel bioreactance technique; patients with an impaired response to exercise exhibit reduced exercise capacity and inefficient ventilation typical of more severe CHF. Non- invasive measurement of cardiac performance in response to exercise provides a simple method of identifying patients with more severe CHF and may complement the CPX in identifying CHF patients at high risk. Key pointsNon-invasive measurement of cardiac output during exercise is feasible in patients with heart failure.Impairment in the CO response to exercise identifies heart failure patients with more severe disease, lower exercise capacity and inefficient ventilation.Non-invasive measurement of cardiac performance during exercise has potentially important applications for the functional and prognostic assessment of patients with heart failure.

  16. Non-invasive cardiac assessment in high risk patients (The GROUND study): rationale, objectives and design of a multi-center randomized controlled clinical trial

    PubMed Central

    de Vos, Alexander M; Rutten, Annemarieke; van de Zaag-Loonen, Hester J; Bots, Michiel L; Dikkers, Riksta; Buiskool, Robert A; Mali, Willem P; Lubbers, Daniel D; Mosterd, Arend; Prokop, Mathias; Rensing, Benno J; Cramer, Maarten J; van Es, H Wouter; Moll, Frans L; van de Pavoordt, Eric D; Doevendans, Pieter A; Velthuis, Birgitta K; Mackaay, Albert J; Zijlstra, Felix; Oudkerk, Matthijs

    2008-01-01

    Background Peripheral arterial disease (PAD) is a common disease associated with a considerably increased risk of future cardiovascular events and most of these patients will die from coronary artery disease (CAD). Screening for silent CAD has become an option with recent non-invasive developments in CT (computed tomography)-angiography and MR (magnetic resonance) stress testing. Screening in combination with more aggressive treatment may improve prognosis. Therefore we propose to study whether a cardiac imaging algorithm, using non-invasive imaging techniques followed by treatment will reduce the risk of cardiovascular disease in PAD patients free from cardiac symptoms. Design The GROUND study is designed as a prospective, multi-center, randomized clinical trial. Patients with peripheral arterial disease, but without symptomatic cardiac disease will be asked to participate. All patients receive a proper risk factor management before randomization. Half of the recruited patients will enter the 'control group' and only undergo CT calcium scoring. The other half of the recruited patients (index group) will undergo the non invasive cardiac imaging algorithm followed by evidence-based treatment. First, patients are submitted to CT calcium scoring and CT angiography. Patients with a left main (or equivalent) coronary artery stenosis of > 50% on CT will be referred to a cardiologist without further imaging. All other patients in this group will undergo dobutamine stress magnetic resonance (DSMR) testing. Patients with a DSMR positive for ischemia will also be referred to a cardiologist. These patients are candidates for conventional coronary angiography and cardiac interventions (coronary artery bypass grafting (CABG) or percutaneous cardiac interventions (PCI)), if indicated. All participants of the trial will enter a 5 year follow up period for the occurrence of cardiovascular events. Sequential interim analysis will take place. Based on sample size calculations about

  17. A robust and reliable non-invasive test for stress responsivity in mice

    PubMed Central

    Zimprich, Annemarie; Garrett, Lillian; Deussing, Jan M.; Wotjak, Carsten T.; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabě; Wurst, Wolfgang; Hölter, Sabine M.

    2014-01-01

    Stress and an altered stress response have been associated with many multifactorial diseases, such as psychiatric disorders or neurodegenerative diseases. As currently mouse mutants for each single gene are generated and phenotyped in a large-scale manner, it seems advisable also to test these mutants for alterations in their stress responses. Here we present the determinants of a robust and reliable non-invasive test for stress-responsivity in mice. Stress is applied through restraining the mice in tubes and recording behavior in the Open Field 20 min after cessation of the stress. Two hours, but not 15 or 50 min of restraint lead to a robust and reproducible increase in distance traveled and number of rearings during the first 5 min in the Open Field in C57BL/6 mice. This behavioral response is blocked by the corticosterone synthesis inhibitor metyrapone, but not by RU486 treatment, indicating that it depends on corticosteroid secretion, but is not mediated via the glucocorticoid receptor type II. We assumed that with a stress duration of 15 min one could detect hyper-responsivity, and with a stress duration of 2 h hypo-responsivity in mutant mouse lines. This was validated with two mutant lines known to show opposing effects on corticosterone secretion after stress exposure, corticotropin-releasing hormone (CRH) over-expressing mice and CRH receptor 1 knockout (KO) mice. Both lines showed the expected phenotype, i.e., increased stress responsivity in the CRH over-expressing mouse line (after 15 min restraint stress) and decreased stress responsivity in the CRHR1-KO mouse line (after 2 h of restraint stress). It is possible to repeat the acute stress test several times without the stressed animal adapting to it, and the behavioral response can be robustly evoked at different ages, in both sexes and in different mouse strains. Thus, locomotor and rearing behavior in the Open Field after an acute stress challenge can be used as reliable, non-invasive indicators of

  18. Thermal Imaging to Study Stress Non-invasively in Unrestrained Birds

    PubMed Central

    Jerem, Paul; Herborn, Katherine; McCafferty, Dominic; McKeegan, Dorothy; Nager, Ruedi

    2015-01-01

    Stress, a central concept in biology, describes a suite of emergency responses to challenges. Among other responses, stress leads to a change in blood flow that results in a net influx of blood to key organs and an increase in core temperature. This stress-induced hyperthermia is used to assess stress. However, measuring core temperature is invasive. As blood flow is redirected to the core, the periphery of the body can cool. This paper describes a protocol where peripheral body temperature is measured non-invasively in wild blue tits (Cyanistes caeruleus) using infrared thermography. In the field we created a set-up bringing the birds to an ideal position in front of the camera by using a baited box. The camera takes a short thermal video recording of the undisturbed bird before applying a mild stressor (closing the box and therefore capturing the bird), and the bird’s response to being trapped is recorded. The bare skin of the eye-region is the warmest area in the image. This allows an automated extraction of the maximum eye-region temperature from each image frame, followed by further steps of manual data filtering removing the most common sources of errors (motion blur, blinking). This protocol provides a time series of eye-region temperature with a fine temporal resolution that allows us to study the dynamics of the stress response non-invasively. Further work needs to demonstrate the usefulness of the method to assess stress, for instance to investigate whether eye-region temperature response is proportional to the strength of the stressor. If this can be confirmed, it will provide a valuable alternative method of stress assessment in animals and will be useful to a wide range of researchers from ecologists, conservation biologists, physiologists to animal welfare researchers. PMID:26575985

  19. Non-invasive evaluation of physiological stress in an iconic Australian marsupial: the Koala (Phascolarctos cinereus).

    PubMed

    Narayan, Edward J; Webster, Koa; Nicolson, Vere; Mucci, Al; Hero, Jean-Marc

    2013-06-15

    Koalas (Phascolarctos cinereus) are the only extant representatives of Australia's unique marsupial family Phascolarctidae and were listed as nationally Vulnerable in 2012. Causes of mortality are diverse, although the disease chlamydiosis, dog attacks, collisions with cars, and loss of habitat represent the principal reasons for the continued species decline. Koala breeding facilities in Queensland and New South Wales, Australia have been established for conservation and tourism. Non-invasive monitoring of physiological stress is important for determining the sub-lethal effects of environmental stressors on the well-being, reproduction and survival of Koalas in Zoos and also in the wild. In this study, we developed a faecal cortisol metabolite (FCM) enzyme-immunoassay (EIA) for monitoring physiological stress in Koalas from two established Zoos in Australia and also within a free-living sub-population from Queensland. Biological validation of the FCM EIA was done using an adrenocorticotropic hormone (ACTH) challenge. We discovered excretory lag-times of FCM of 24 h in females (n=2) and 48 h in male (n=2) Koalas in response to the ACTH challenge. FCM levels showed an episodic and delayed peak response lasting up to 9 days post ACTH challenge. This finding should be taken into consideration when designing future experiments to study the impacts of short-term (acute) and chronic stressors on the Koalas. Laboratory validations were done using parallelism and recovery checks (extraction efficiency) of the cortisol standard against pooled Koala faecal extracts. Greater than 99% recovery of the cortisol standard was obtained as well as a parallel displacement curve against Koala faecal extracts. FCM levels of the captive Koalas (n=10 males and 13 females) significantly differed by sex, reproductive condition (lactating versus non-lactating Koalas) and the handling groups. Handled male Koalas had 200% higher FCM levels than their non-handled counterparts, while females

  20. Towards real-time MRI-guided 3D localization of deforming targets for non-invasive cardiac radiosurgery.

    PubMed

    Ipsen, S; Blanck, O; Lowther, N J; Liney, G P; Rai, R; Bode, F; Dunst, J; Schweikard, A; Keall, P J

    2016-11-21

    Radiosurgery to the pulmonary vein antrum in the left atrium (LA) has recently been proposed for non-invasive treatment of atrial fibrillation (AF). Precise real-time target localization during treatment is necessary due to complex respiratory and cardiac motion and high radiation doses. To determine the 3D position of the LA for motion compensation during radiosurgery, a tracking method based on orthogonal real-time MRI planes was developed for AF treatments with an MRI-guided radiotherapy system. Four healthy volunteers underwent cardiac MRI of the LA. Contractile motion was quantified on 3D LA models derived from 4D scans with 10 phases acquired in end-exhalation. Three localization strategies were developed and tested retrospectively on 2D real-time scans (sagittal, temporal resolution 100 ms, free breathing). The best-performing method was then used to measure 3D target positions in 2D-2D orthogonal planes (sagittal-coronal, temporal resolution 200-252 ms, free breathing) in 20 configurations of a digital phantom and in the volunteer data. The 3D target localization accuracy was quantified in the phantom and qualitatively assessed in the real data. Mean cardiac contraction was  ⩽  3.9 mm between maximum dilation and contraction but anisotropic. A template matching approach with two distinct template phases and ECG-based selection yielded the highest 2D accuracy of 1.2 mm. 3D target localization showed a mean error of 3.2 mm in the customized digital phantoms. Our algorithms were successfully applied to the 2D-2D volunteer data in which we measured a mean 3D LA motion extent of 16.5 mm (SI), 5.8 mm (AP) and 3.1 mm (LR). Real-time target localization on orthogonal MRI planes was successfully implemented for highly deformable targets treated in cardiac radiosurgery. The developed method measures target shifts caused by respiration and cardiac contraction. If the detected motion can be compensated accordingly, an MRI-guided radiotherapy

  1. Towards real-time MRI-guided 3D localization of deforming targets for non-invasive cardiac radiosurgery

    NASA Astrophysics Data System (ADS)

    Ipsen, S.; Blanck, O.; Lowther, N. J.; Liney, G. P.; Rai, R.; Bode, F.; Dunst, J.; Schweikard, A.; Keall, P. J.

    2016-11-01

    Radiosurgery to the pulmonary vein antrum in the left atrium (LA) has recently been proposed for non-invasive treatment of atrial fibrillation (AF). Precise real-time target localization during treatment is necessary due to complex respiratory and cardiac motion and high radiation doses. To determine the 3D position of the LA for motion compensation during radiosurgery, a tracking method based on orthogonal real-time MRI planes was developed for AF treatments with an MRI-guided radiotherapy system. Four healthy volunteers underwent cardiac MRI of the LA. Contractile motion was quantified on 3D LA models derived from 4D scans with 10 phases acquired in end-exhalation. Three localization strategies were developed and tested retrospectively on 2D real-time scans (sagittal, temporal resolution 100 ms, free breathing). The best-performing method was then used to measure 3D target positions in 2D-2D orthogonal planes (sagittal-coronal, temporal resolution 200-252 ms, free breathing) in 20 configurations of a digital phantom and in the volunteer data. The 3D target localization accuracy was quantified in the phantom and qualitatively assessed in the real data. Mean cardiac contraction was  ⩽  3.9 mm between maximum dilation and contraction but anisotropic. A template matching approach with two distinct template phases and ECG-based selection yielded the highest 2D accuracy of 1.2 mm. 3D target localization showed a mean error of 3.2 mm in the customized digital phantoms. Our algorithms were successfully applied to the 2D-2D volunteer data in which we measured a mean 3D LA motion extent of 16.5 mm (SI), 5.8 mm (AP) and 3.1 mm (LR). Real-time target localization on orthogonal MRI planes was successfully implemented for highly deformable targets treated in cardiac radiosurgery. The developed method measures target shifts caused by respiration and cardiac contraction. If the detected motion can be compensated accordingly, an MRI-guided radiotherapy

  2. Mechanography: a non-invasive technique for the evaluation of cardiac function in children

    PubMed Central

    Spitaels, Silja; Fouron, Jean-Claude; Davignon, André

    1972-01-01

    Experience in the pediatric age group with mechanography, an indirect method of cardiovascular investigation, is described with emphasis on the recording technique and on the analysis of the tracings. A few examples are presented with comments on the morphological aspects and the time characteristics of the pulse curves, showing how much information about cardiac disease and especially myocardial function in children may be obtained. PMID:4640813

  3. (Non-invasive evaluation of the cardiac autonomic nervous system by PET)

    SciTech Connect

    Not Available

    1992-01-01

    The proposed research addresses the development, validation and application of cardiac PET imaging techniques to characterize the autonomic nervous system of the heart. PET technology has significantly matured over the last two decades. Instrument design, image processing and production of radiochemical compounds have formed an integrative approach to provide a powerful and novel imaging modality for the quantitative in vivo evaluation of the autonomic nervous system of the heart. Animal studies using novel tracers for the sympathetic and parasympathetic nerve terminals will be employed to characterize the functional integrity of nerve terminals. This work will be complemented by the development of agents which bind to postsynaptic receptor sites. The combined evaluation of presynaptic and postsynaptic neuronal function will allow a unique characterization of neuronal function. Initial development in animal studies will be followed by feasibility studies in humans. These studies are designed to test sophisticated imaging protocols in the human heart and validate the scintigraphic findings with independent markers of autonomic innervation. Subsequent clinical application in various cardiac diseases is expected to provide new insights into the neuropathophysiology of the heart.

  4. A non-invasive approach to investigation of ventricular blood pressure using cardiac sound features.

    PubMed

    Tang, Hong; Zhang, Jinghui; Chen, Huaming; Mondal, Ashok; Park, Yongwan

    2017-02-01

    Heart sounds (HSs) are produced by the interaction of the heart valves, great vessels, and heart wall with blood flow. Previous researchers have demonstrated that blood pressure can be predicted by exploring the features of cardiac sounds. These features include the amplitude of the HSs, the ratio of the amplitude, the systolic time interval, and the spectrum of the HSs. A single feature or combinations of several features have been used for prediction of blood pressure with moderate accuracy. Experiments were conducted with three beagles under various levels of blood pressure induced by different doses of epinephrine. The HSs, blood pressure in the left ventricle and electrocardiograph signals were simultaneously recorded. A total of 31 records (18 262 cardiac beats) were collected. In this paper, 91 features in various domains are extracted and their linear correlations with the measured blood pressures are examined. These features are divided into four groups and applied individually at the input of a neural network to predict the left ventricular blood pressure (LVBP). The analysis shows that non-spectral features can track changes of the LVBP with lower standard deviation. Consequently, the non-spectral feature set gives the best prediction accuracy. The average correlation coefficient between the measured and the predicted blood pressure is 0.92 and the mean absolute error is 6.86 mmHg, even when the systolic blood pressure varies in the large range from 90 mmHg to 282 mmHg. Hence, systolic blood pressure can be accurately predicted even when using fewer HS features. This technique can be used as an alternative to real-time blood pressure monitoring and it has promising applications in home health care environments.

  5. [Non-invasive evaluation of the cardiac autonomic nervous system by PET]. Progress report

    SciTech Connect

    Not Available

    1992-12-01

    C-11 hydroxy ephedrine, introduced as the first clinically usable norepinephrine analogue, studies employing normal volunteers and patients with various cardiac disorders was found to valuable as a nonadreneric tracer. Simultaneously, animal studies been used to assess its use following ischemic injury in order to define neuronal damage. Current research focuses on the comparison of C-11 hydroxyephedrine with other neurotransmitters such as C-11 epinephrine and C-11 threohydroxyephedrine. Epinephrine is primarily stored in vesicles of the nerve terminal, while threo-hydroxyephedrine is only substrate to uptake I mechanism. Such a combination of radiotracers may allow the dissection of uptake I mechanism as well as vesicular storage. In parallel to the refinement of presynaptic tracers for the sympathetic nervous system, we are developing radiopharmaceuticals to delineate the adrenergic receptors in the heart. The combined evaluation of pre- and postsynaptic nerve function will improve our ability to identify abnormalides. We are currently developing a new radiosynthesis of the hydrophilic adrenergic receptor antagonist C-11 CGP-12177 which has been used by others for the visualization of adrenergic receptors in the heart. We are developing radiopharmaceuticals, for the delineation of presynaptic cholinergic nerve terminals. Derivatives of benzovesamicol have been labeled in our institution and are currently under investigation. The most promising agent is F-18 benzovesamicol (FEBOBV) which allows the visualization of parasympathetic nerve terminals in the canine heart as demonstrated by, preliminary PET data.

  6. [Non-invasive evaluation of the cardiac autonomic nervous system by PET

    SciTech Connect

    Not Available

    1992-01-01

    C-11 hydroxy ephedrine, introduced as the first clinically usable norepinephrine analogue, studies employing normal volunteers and patients with various cardiac disorders was found to valuable as a nonadreneric tracer. Simultaneously, animal studies been used to assess its use following ischemic injury in order to define neuronal damage. Current research focuses on the comparison of C-11 hydroxyephedrine with other neurotransmitters such as C-11 epinephrine and C-11 threohydroxyephedrine. Epinephrine is primarily stored in vesicles of the nerve terminal, while threo-hydroxyephedrine is only substrate to uptake I mechanism. Such a combination of radiotracers may allow the dissection of uptake I mechanism as well as vesicular storage. In parallel to the refinement of presynaptic tracers for the sympathetic nervous system, we are developing radiopharmaceuticals to delineate the adrenergic receptors in the heart. The combined evaluation of pre- and postsynaptic nerve function will improve our ability to identify abnormalides. We are currently developing a new radiosynthesis of the hydrophilic adrenergic receptor antagonist C-11 CGP-12177 which has been used by others for the visualization of adrenergic receptors in the heart. We are developing radiopharmaceuticals, for the delineation of presynaptic cholinergic nerve terminals. Derivatives of benzovesamicol have been labeled in our institution and are currently under investigation. The most promising agent is F-18 benzovesamicol (FEBOBV) which allows the visualization of parasympathetic nerve terminals in the canine heart as demonstrated by, preliminary PET data.

  7. Design and testing of an MRI-compatible cycle ergometer for non-invasive cardiac assessments during exercise

    PubMed Central

    2012-01-01

    Background Magnetic resonance imaging (MRI) is an important tool for cardiac research, and it is frequently used for resting cardiac assessments. However, research into non-pharmacological stress cardiac evaluation is limited. Methods We aimed to design a portable and relatively inexpensive MRI cycle ergometer capable of continuously measuring pedalling workload while patients exercise to maintain target heart rates. Results We constructed and tested an MRI-compatible cycle ergometer for a 1.5 T MRI scanner. Resting and sub-maximal exercise images (at 110 beats per minute) were successfully obtained in 8 healthy adults. Conclusions The MRI-compatible cycle ergometer constructed by our research group enabled cardiac assessments at fixed heart rates, while continuously recording power output by directly measuring pedal force and crank rotation. PMID:22423637

  8. An open-source framework for stress-testing non-invasive foetal ECG extraction algorithms.

    PubMed

    Andreotti, Fernando; Behar, Joachim; Zaunseder, Sebastian; Oster, Julien; Clifford, Gari D

    2016-05-01

    Over the past decades, many studies have been published on the extraction of non-invasive foetal electrocardiogram (NI-FECG) from abdominal recordings. Most of these contributions claim to obtain excellent results in detecting foetal QRS (FQRS) complexes in terms of location. A small subset of authors have investigated the extraction of morphological features from the NI-FECG. However, due to the shortage of available public databases, the large variety of performance measures employed and the lack of open-source reference algorithms, most contributions cannot be meaningfully assessed. This article attempts to address these issues by presenting a standardised methodology for stress testing NI-FECG algorithms, including absolute data, as well as extraction and evaluation routines. To that end, a large database of realistic artificial signals was created, totaling 145.8 h of multichannel data and over one million FQRS complexes. An important characteristic of this dataset is the inclusion of several non-stationary events (e.g. foetal movements, uterine contractions and heart rate fluctuations) that are critical for evaluating extraction routines. To demonstrate our testing methodology, three classes of NI-FECG extraction algorithms were evaluated: blind source separation (BSS), template subtraction (TS) and adaptive methods (AM). Experiments were conducted to benchmark the performance of eight NI-FECG extraction algorithms on the artificial database focusing on: FQRS detection and morphological analysis (foetal QT and T/QRS ratio). The overall median FQRS detection accuracies (i.e. considering all non-stationary events) for the best performing methods in each group were 99.9% for BSS, 97.9% for AM and 96.0% for TS. Both FQRS detections and morphological parameters were shown to heavily depend on the extraction techniques and signal-to-noise ratio. Particularly, it is shown that their evaluation in the source domain, obtained after using a BSS technique, should be

  9. Addressing Assumptions for the Use of Non-invasive Cardiac Output Measurement Techniques During Exercise in COPD.

    PubMed

    Perrault, Hélène; Richard, Ruddy; Kapchinsky, Sophia; Baril, Jacinthe; Bourbeau, Jean; Taivassalo, Tanja

    2016-01-01

    The multifactorial functional limitation of COPD increasingly demonstrates the need for an integrated circulatory assessment. In this study cardiac output (Qc) derived from non-inert (CO2-RB), inert (N2O-RB) gas rebreathing approaches and bioimpedance were compared to examine the limitations of currently available non-invasive techniques for exercise Qc determination in patients with chronic lung disease. Thirteen COPD patients (GOLD II-III) completed three constant cycling bouts at 20, 35, and 50% of peak work on two occasions to assess Qc with bioimpedance as well as using CO2-RB and N2O-RB for all exercise tests. Results showed significantly lower Qc using the N2O-RB or end-tidal CO2-derived Qc compared to the PaCO2-derived CO2-RB or the bioimpedance at rest and for all exercise intensities. End-tidal CO2-derived values are however not statistically different from those obtained using inert-gas rebreathing. This study show that in COPD patients, CO2-rebreathing Qc values obtained using PaCO2 contents which account for any gas exchange impairment or inadequate gas mixing are similar to those obtained using thoracic bioimpedance. Alternately, the lower values for N2O rebreathing derived Qc indicates the inability of this technique to account for gas exchange impairment in the computation of Qc. These findings indicate that the choice of a gas rebreathing technique to measure Qc in patients must be dictated by the ability to include in the derived computations a correction for either gas exchange inadequacies and/or a vascular shunt.

  10. Non-invasive stratification of postinfarction rats based on degree of cardiac dysfunction using magnetic resonance imaging and echocardiography.

    PubMed

    Aronsen, Jan Magnus; Espe, Emil Knut Stenersen; Skårdal, Kristine; Hasic, Almira; Zhang, Lili; Sjaastad, Ivar

    2017-02-10

    The myocardial infarction (MI) rat model plays a crucial role in modern cardiovascular research, but the inherent heterogeneity of this model represents a challenge. We sought to identify subgroups among the post-MI rats, and establish simple non-invasive stratification protocols for such subgroups. Six weeks after induction of MI, 49 rats underwent non-invasive examinations using magnetic resonance imaging (MRI) and echocardiography. 12 sham-operated rats served as controls. Increased end-diastolic left ventricular (LV) pressure and lung weight served as indicators for congestive heart failure (CHF). A clustering algorithm using thirteen non-invasive and invasive parameters was used to identify distinct groups among the animals. The cluster analysis revealed four distinct post-MI phenotypes; two without congestion but with different degree of LV dilatation, and two with different degree of congestion and right ventricular (RV) affection. Among the MRI parameters, RV mass emerged as robust non-invasive marker of CHF with 100% specificity/sensitivity. Moreover, LV infarct size and RV ejection fraction further predicted subgroup among the non-CHF and CHF rats with excellent specificity/sensitivity. Of the echocardiography parameters, left atrial diameter predicted CHF. Moreover, MRI-derived LV end-diastolic diameter predicted the subgroups among the non-CHF rats. We propose two simple non-invasive schemes to stratify post-MI rats, based on the degree of heart failure; one for MRI and one for echocardiography.

  11. Non-invasive monitoring of stress hormones in the bat Eptesicus isabellinus - Do fecal glucocorticoid metabolite concentrations correlate with survival?

    PubMed

    Kelm, Detlev H; Popa-Lisseanu, Ana G; Dehnhard, Martin; Ibáñez, Carlos

    2016-01-15

    Chronic stress may negatively impact fitness and survival in wildlife. Stress hormone analysis from feces is a non-invasive tool for identifying stressors and deducing about individual and population level fitness. Although many bat populations are endangered, fecal stress hormone analysis has not been established in bats as a method for focusing conservation efforts. The isabelline serotine bat, Eptesicus isabellinus, is exposed to human disturbance as its roosts are mostly found in anthropogenic structures. Moreover, this bat is host to various diseases and survival rates between colonies may vary significantly. To validate the analysis of fecal glucocorticoid metabolites, we applied an adrenocorticotropic hormone (ACTH) challenge and tested four different enzyme immunoassays (EIA) for measuring glucocorticoid concentrations. Cortisol and its metabolites showed the highest increase in blood and feces after the ACTH challenge, but corticosterone and its metabolites also increased significantly. Baseline fecal cortisol metabolite (FCM) concentrations did not increase until 1.5h after the animals were captured, which is a convenient time lag for sample collection from captured animals. We furthermore compared baseline FCM concentrations between five colonies of E. isabellinus in Andalusia, Spain, and tested for their correlation with survival rates. FCM concentrations did not vary between colonies, but FCM levels increased with the animals' age. FCM analysis may prove a useful tool for identifying bat colonies that experience uncommon environmental stress. However, inter-individual variation in hormone secretion, due to factors such as age, may require additional information to properly interpret differences in hormone concentrations.

  12. Non-invasive assessment of reproductive status and stress in captive Asian elephants in three south Indian zoos.

    PubMed

    Kumar, Vinod; Palugulla Reddy, Vivekananda; Kokkiligadda, Adiseshu; Shivaji, Sisinthy; Umapathy, Govindhaswamy

    2014-05-15

    Asian elephants in captivity need immediate attention to be bred so as to meet the increasing demand for captive elephants and to overcome the dependence on supplementing the captive stock with wild animals. Unfortunately, captive breeding programs across the globe have met with limited success and therefore more effort is needed to improve breeding in captivity. Endocrine profiling of reproductive hormones (progestagens and androgens) and the stress hormone (glucocorticoids) could facilitate better management and breeding strategies. In the present study, we investigated reproductive and stress physiology of 12 captive Asian elephants for 10-27 months using a non-invasive method based on steroid analysis of 1700 elephant dung samples. Most of the elephants were cycling regularly. Males during musth showed increased fecal androgen metabolite concentrations and exhibited a slight increase in fecal glucocorticoid metabolite levels. Elephants used in public festivals and processions showed significantly increased in faecal glucocorticoid metabolite levels. The results indicate that captive elephants require periodic health care, better husbandry practices and scientific management for sustainable captive population.

  13. [Non-invasive evaluation of the cardiac autonomic nervous system by PET]. Progress report, September 1991--September 1992

    SciTech Connect

    Not Available

    1992-09-01

    The proposed research addresses the development, validation and application of cardiac PET imaging techniques to characterize the autonomic nervous system of the heart. PET technology has significantly matured over the last two decades. Instrument design, image processing and production of radiochemical compounds have formed an integrative approach to provide a powerful and novel imaging modality for the quantitative in vivo evaluation of the autonomic nervous system of the heart. Animal studies using novel tracers for the sympathetic and parasympathetic nerve terminals will be employed to characterize the functional integrity of nerve terminals. This work will be complemented by the development of agents which bind to postsynaptic receptor sites. The combined evaluation of presynaptic and postsynaptic neuronal function will allow a unique characterization of neuronal function. Initial development in animal studies will be followed by feasibility studies in humans. These studies are designed to test sophisticated imaging protocols in the human heart and validate the scintigraphic findings with independent markers of autonomic innervation. Subsequent clinical application in various cardiac diseases is expected to provide new insights into the neuropathophysiology of the heart.

  14. Identifying Model Inaccuracies and Solution Uncertainties in Non-Invasive Activation-Based Imaging of Cardiac Excitation using Convex Relaxation

    PubMed Central

    Erem, Burak; van Dam, Peter M.; Brooks, Dana H.

    2014-01-01

    Noninvasive imaging of cardiac electrical function has begun to move towards clinical adoption. Here we consider one common formulation of the problem, in which the goal is to estimate the spatial distribution of electrical activation times during a cardiac cycle. We address the challenge of understanding the robustness and uncertainty of solutions to this formulation. This formulation poses a non-convex, non-linear least squares optimization problem. We show that it can be relaxed to be convex, at the cost of some degree of physiological realism of the solution set, and that this relaxation can be used as a framework to study model inaccuracy and solution uncertainty. We present two examples, one using data from a healthy human subject and the other synthesized with the ECGSIM software package. In the first case, we consider uncertainty in the initial guess and regularization parameter. In the second case, we mimic the presence of an ischemic zone in the heart in a way which violates a model assumption. We show that the convex relaxation allows understanding of spatial distribution of parameter sensitivity in the first case, and identification of model violation in the second. PMID:24710159

  15. Utility of T-wave amplitude as a non-invasive risk marker of sudden cardiac death in hypertrophic cardiomyopathy

    PubMed Central

    Sugrue, Alan; Killu, Ammar M; DeSimone, Christopher V; Chahal, Anwar A; Vogt, Josh C; Kremen, Vaclav; Hai, JoJo; Hodge, David O; Acker, Nancy G; Geske, Jeffrey B; Ackerman, Michael J; Ommen, Steve R; Lin, Grace; Noseworthy, Peter A; Brady, Peter A

    2017-01-01

    Objective Sudden cardiac arrest (SCA) is the most devastating outcome in hypertrophic cardiomyopathy (HCM). We evaluated repolarisation features on the surface electrocardiogram (ECG) to identify the potential risk factors for SCA. Methods Data was collected from 52 patients with HCM who underwent implantable cardioverter defibrillator (ICD) implantation. Leads V2 and V5 from the ECG closest to the time of ICD implant were utilised for measuring the Tpeak-Tend interval (Tpe), QTc, Tpe/QTc, T-wave duration and T-wave amplitude. The presence of the five traditional SCA-associated risk factors was assessed, as well as the HCM risk-SCD score. Results 16 (30%) patients experienced aborted cardiac arrest over 8.5±4.1 years, with 9 receiving an ICD shock and 7 receiving ATP. On univariate analysis, T-wave amplitude was associated with appropriate ICD therapy (HR per 0.1 mV 0.79, 95% CI 0.56 to 0.96, p=0.02). Aborted SCA was not associated with a greater mean QTc duration, Tpeak-Tend interval, T-wave duration, or Tpe/QT ratio. Multivariate analysis (adjusting for cardinal HCM SCA-risk factors) showed T-wave amplitude in Lead V2 was an independent predictor of risk (adjusted HR per 0.1 mV 0.74, 95% CI 0.57 to 0.97, p=0.03). Addition of T-wave amplitude in Lead V2 to the traditional risk factors resulted in significant improvement in risk stratification (C-statistic from 0.65 to 0.75) but did not improve the performance of the HCM SCD-risk score. Conclusions T-wave amplitude is a novel marker of SCA in this high risk HCM population and may provide incremental predictive value to established risk factors. Further work is needed to define the role of repolarisation abnormalities in predicting SCA in HCM.

  16. Effectiveness of prophylactic non-invasive ventilation on respiratory function in the postoperative phase of pediatric cardiac surgery: a randomized controlled trial

    PubMed Central

    Silva, Camilla R. S.; Andrade, Lívia B.; Maux, Danielle A. S. X.; Bezerra, Andreza L.; Duarte, Maria C. M. B.

    2016-01-01

    ABSTRACT Objective To evaluate the effectiveness of prophylactic, non-invasive ventilation (NIV) on respiratory function in seven- to 16-year-old children in the post-operative phase of cardiac surgery. Method A randomized, controlled trial with 50 children who had undergone cardiac surgery with median sternotomy. After extubation, patients were randomly assigned to one of two groups: control group (n=26), which received instructions regarding posture, early ambulation, and cough stimulation, and CPAP group (continuous positive airway pressure; n=24), which received the same instructions as the control group and CPAP=10 cmH20 twice daily for 30 minutes from the 1st to the 5th post-operative day (POD). As a primary outcome, lung function was evaluated before and on the 1st, 3rd, and 5th PODs with measures of respiratory rate (RR), tidal volume (TV), slow vital capacity (SVC), inspiratory capacity (IC), minute volume (MV), peak expiratory flow (PEF), and maximal inspiratory pressure (MIP). As secondary outcomes, the time of hospitalization and intensive care were recorded. A mixed, linear regression model and z-test were used to analyze respiratory function, considering p<0.05. Results All variables, except RR and MV, showed a significant drop on the 1st POD, with gradual recovery; however, only MIP had returned to pre-operative values on the 5th POD in both groups. The RR showed a significant increase on the 1st POD, with a gradual reduction but without returning to baseline. In the intergroup analysis, significant improvement (p=0.04) was observed only in PEF in the CPAP group on the 1st DPO. The length of hospitalization and intensive care showed no significant differences. Conclusion NIV was safe and well accepted in this group of patients, and the protocol used was effective in improving PEF on the 1st DPO in the CPAP group. PMID:27706462

  17. SU-C-303-06: Treatment Planning Study for Non-Invasive Cardiac Arrhythmia Ablation with Scanned Carbon Ions in An Animal Model

    SciTech Connect

    Eichhorn, A; Constantinescu, A; Prall, M; Kaderka, R; Durante, M; Graeff, C; Lehmann, H I; Takami, M; Packer, D L; Lugenbiel, P; Thomas, D; Richter, D; Bert, C

    2015-06-15

    Purpose: Scanned carbon ion beams might offer a non-invasive alternative treatment for cardiac arrhythmia, which are a major health-burden. We studied the feasibility of this procedure in an animal model. The underlying treatment planning and motion mitigation strategies will be presented. Methods: The study was carried out in 15 pigs, randomly distributed to 3 target groups: atrioventricular node (AVN, 8 animals with 25, 40, and 55 Gy target dose), left ventricular free-wall (LV, 4 animals with 40 Gy) and superior pulmonary vein (SPV, 3 animals with 40 Gy). Breathing motion was suppressed by repeated enforced breathholds at end exhale. Cardiac motion was mitigated by an inhomogeneous rescanning scheme with up to 15 rescans. The treatment planning was performed using the GSI in-house software TRiP4D on cardiac-gated 4DCTs, applying a range-considering ITV based on an extended CTV. For AVN and SPV isotropic 5 mm margins were applied to the CTV, while for the LV 2mm+2% range margins were used. The opposing fields for AVN and LV targets were optimized independently (SFUD), while SPV treatments were optimized as IMPT deliveries, including dose restrictions to the radiosensitive AVN. Results: Median value of D{sub 95} over all rescanning simulations was 99.1% (AVN), 98.0% (SPV) and 98.3% (LV) for the CTV and 94.7% (AVN) and 92.7% (SPV) for the PTV, respectively. The median D{sub 5}-D{sub 95} was improved with rescanning compared to unmitigated delivery from 13.3 to 6.5% (CTV) and from 23.4 to 11.6% (PTV). ICRP dose limits for aorta, trachea, esophagus and skin were respected. The maximal dose in the coronary arteries was limited to 30 Gy. Conclusion: We demonstrated the feasibility of a homogeneous dose delivery to different cardiac structures in a porcine model using a time-optimized inhomogeneous rescanning scheme. The presented treatment planning strategies were applied in a pig study with the analysis ongoing. Funding: This work was supported in part by the

  18. Prediction of rectal temperature using non-invasive physiologic variable measurements in hair pregnant ewes subjected to natural conditions of heat stress.

    PubMed

    Vicente-Pérez, Ricardo; Avendaño-Reyes, Leonel; Mejía-Vázquez, Ángel; Álvarez-Valenzuela, F Daniel; Correa-Calderón, Abelardo; Mellado, Miguel; Meza-Herrera, Cesar A; Guerra-Liera, Juan E; Robinson, P H; Macías-Cruz, Ulises

    2016-01-01

    Rectal temperature (RT) is the foremost physiological variable indicating if an animal is suffering hyperthermia. However, this variable is traditionally measured by invasive methods, which may compromise animal welfare. Models to predict RT have been developed for growing pigs and lactating dairy cows, but not for pregnant heat-stressed ewes. Our aim was to develop a prediction equation for RT using non-invasive physiological variables in pregnant ewes under heat stress. A total of 192 records of respiratory frequency (RF) and hair coat temperature in various body regions (i.e., head, rump, flank, shoulder, and belly) obtained from 24 Katahdin × Pelibuey pregnant multiparous ewes were collected during the last third of gestation (i.e., d 100 to lambing) with a 15 d sampling interval. Hair coat temperatures were taken using infrared thermal imaging technology. Initially, a Pearson correlation analysis examined the relationship among variables, and then multiple linear regression analysis was used to develop the prediction equations. All predictor variables were positively correlated (P<0.01; r=0.59-0.67) with RT. The adjusted equation which best predicted RT (P<0.01; Radj(2)=56.15%; CV=0.65%) included as predictors RF and head and belly temperatures. Comparison of predicted and observed values for RT indicates a suitable agreement (P<0.01) between them with moderate accuracy (Radj(2)=56.15%) when RT was calculated with the adjusted equation. In general, the final equation does not violate any assumption of multiple regression analysis. The RT in heat-stressed pregnant ewes can be predicted with an adequate accuracy using non-invasive physiologic variables, and the final equation was: RT=35.57+0.004 (RF)+0.067 (heat temperature)+0.028 (belly temperature).

  19. Non-Invasive Assessment of the Interrelationships of Diet, Pregnancy Rate, Group Composition, and Physiological and Nutritional Stress of Barren-Ground Caribou in Late Winter.

    PubMed

    Joly, Kyle; Wasser, Samuel K; Booth, Rebecca

    2015-01-01

    The winter diet of barren-ground caribou may affect adult survival, timing of parturition, neonatal survival, and postpartum mass. We used microhistological analyses and hormone levels in feces to determine sex-specific late-winter diets, pregnancy rates, group composition, and endocrine-based measures of physiological and nutritional stress. Lichens, which are highly digestible but contain little protein, dominated the diet (> 68%) but were less prevalent in the diets of pregnant females as compared to non-pregnant females and males. The amount of lichens in the diets of pregnant females decreased at higher latitudes and as winter progressed. Pregnancy rates (82.1%, 95% CI = 76.0 - 88.1%) of adult cows were within the expected range for a declining herd, while pregnancy status was not associated with lichen abundance in the diet. Most groups (80%) were of mixed sex. Male: female ratios (62:100) were not skewed enough to affect the decline. Levels of hormones indicating nutritional stress were detected in areas of low habitat quality and at higher latitudes. Levels of hormones indicated that physiological stress was greatest for pregnant cows, which faced the increasing demands of gestation in late winter. These fecal-based measures of diet and stress provided contextual information for the potential mechanisms of the ongoing decline. Non-invasive techniques, such as monitoring diets, pregnancy rates, sex ratios and stress levels from fecal samples, will become increasingly important as monitoring tools as the industrial footprint continues to expand in the Arctic.

  20. Aerial Imagery and Other Non-invasive Approaches to Detect Nitrogen and Water Stress in a Potato Crop

    NASA Astrophysics Data System (ADS)

    Nigon, Tyler John

    Post-emergence nitrogen (N) fertilizer is typically split applied to irrigated potato (Solanum tuberosum L.) in Minnesota in order to minimize the likelihood of nitrate leaching and to best match N availability to crop demands. Petiole nitrate-nitrogen (NO3-N) concentration is often used as a diagnostic test to determine the rate and timing of split applications, but using this approach for variable rate applications is difficult. Canopy-level spectral measurements, such as hyperspectral and multispectral imagery, have the potential to be a reliable tool for making in-season N management decisions for precision agriculture applications. The objectives of this two year field study were to evaluate the effects of variety, N treatment, and water stress on growth characteristics and the ability of and canopy-level reflectance to predict N stress in potato. Treatments included two irrigation regimes (unstressed and stressed), five N regimes categorized by three N rates (34 kg N ha-1, 180 kg N ha-1, and 270 kg N ha-1) in which the 270 kg N ha-1 rate had post-emergence N either split applied or applied early in the season, and two potato varieties (Russet Burbank and Alpine Russet). Higher N rates and split applications generally resulted in higher tuber yield for both varieties. Insufficient supplemental water was found to reduce tuber yield and plant N uptake. Of the broadband indices, narrowband indices, and partial least squares regression (PLS) models evaluated, the best predictor of N stress as measured by leaf N concentration was the PLS model using derivative reflectance (r2 of 0.79 for RB and 0.77 for AR). However, the best technique for determining N stress level for variable rate application of N fertilizer was MTCI (MERIS Terrestrial Chlorophyll Index) due to its good relationship with leaf N concentration and high accuracy. As a final aspect of the study, results from the experimental plots were used to predict N stress in a

  1. Portable oxidative stress sensor: dynamic and non-invasive measurements of extracellular H₂O₂ released by algae.

    PubMed

    Koman, Volodymyr B; Santschi, Christian; von Moos, Nadia R; Slaveykova, Vera I; Martin, Olivier J F

    2015-06-15

    Reactive oxygen species (ROS) generated by aerobic organisms are essential for physiological processes such as cell signaling, apoptosis, immune defense and oxidative stress mechanisms. Unbalanced oxidant/antioxidant budgets are involved in many diseases and, therefore, the sensitive measurement of ROS is of great interest. Here, we present a new device for the real-time monitoring of oxidative stress by measuring one of the most stable ROS, namely hydrogen peroxide (H2O2). This portable oxidative stress sensor contains the heme protein cytochrome c (cyt c) as sensing element whose spectral response enables the detection of H2O2 down to a detection limit of 40 nM. This low detection limit is achieved by introducing cyt c in a random medium, enabling multiscattering that enhances the optical trajectory through the cyt c spot. A contact microspotting technique is used to produce reproducible and reusable cyt c spots which are stable for several days. Experiments in static and microfluidic regimes, as well as numerical simulations demonstrate the suitability of the cyt c/H2O2 reaction system for the real-time sensing of the kinetics of biological processes without H2O2 depletion in the measurement chamber. As an example, we detect the release of H2O2 from the green alga Chlamydomonas reinhardtii exposed to either 180 nM functionalized CdSe/ZnS core shell quantum dots, or to 10 mg/l TiO2 nanoparticles. The continuous measurement of extracellular H2O2 by this optical sensor with high sensitivity is a promising new means for real-time cytotoxicity tests, the investigation of oxidative stress and other physiological cell processes.

  2. Non-Invasive Assessment of the Interrelationships of Diet, Pregnancy Rate, Group Composition, and Physiological and Nutritional Stress of Barren-Ground Caribou in Late Winter

    PubMed Central

    Joly, Kyle; Wasser, Samuel K.; Booth, Rebecca

    2015-01-01

    The winter diet of barren-ground caribou may affect adult survival, timing of parturition, neonatal survival, and postpartum mass. We used microhistological analyses and hormone levels in feces to determine sex-specific late-winter diets, pregnancy rates, group composition, and endocrine-based measures of physiological and nutritional stress. Lichens, which are highly digestible but contain little protein, dominated the diet (> 68%) but were less prevalent in the diets of pregnant females as compared to non-pregnant females and males. The amount of lichens in the diets of pregnant females decreased at higher latitudes and as winter progressed. Pregnancy rates (82.1%, 95% CI = 76.0 – 88.1%) of adult cows were within the expected range for a declining herd, while pregnancy status was not associated with lichen abundance in the diet. Most groups (80%) were of mixed sex. Male: female ratios (62:100) were not skewed enough to affect the decline. Levels of hormones indicating nutritional stress were detected in areas of low habitat quality and at higher latitudes. Levels of hormones indicated that physiological stress was greatest for pregnant cows, which faced the increasing demands of gestation in late winter. These fecal-based measures of diet and stress provided contextual information for the potential mechanisms of the ongoing decline. Non-invasive techniques, such as monitoring diets, pregnancy rates, sex ratios and stress levels from fecal samples, will become increasingly important as monitoring tools as the industrial footprint continues to expand in the Arctic. PMID:26061003

  3. Multiobjective optimization of cartilage stress for non-invasive, patient-specific recommendations of high tibial osteotomy correction angle - a novel method to investigate alignment correction.

    PubMed

    Zheng, Keke; Scholes, Corey J; Chen, Junning; Parker, David; Li, Qing

    2017-04-01

    Medial opening wedge high tibial osteotomy (MOWHTO) is a surgical procedure to treat knee osteoarthritis associated with varus deformity. However, the ideal final alignment of the Hip-Knee-Ankle (HKA) angle in the frontal plane, that maximizes procedural success and post-operative knee function, remains controversial. Therefore, the purpose of this study was to introduce a subject-specific modeling procedure in determining the biomechanical effects of MOWHTO alignment on tibiofemoral cartilage stress distribution. A 3D finite element knee model derived from magnetic resonance imaging of a healthy participant was manipulated in-silico to simulate a range of final HKA angles (i.e. 0.2°, 2.7°, 3.9° and 6.6° valgus). Loading and boundary conditions were assigned based on subject-specific kinematic and kinetic data from gait analysis. Multiobjective optimization was used to identify the final alignment that balanced compressive and shear forces between medial and lateral knee compartments. Peak stresses decreased in the medial and increased in the lateral compartment as the HKA was shifted into valgus, with balanced loading occurring at angles of 4.3° and 2.9° valgus for the femoral and tibial cartilage respectively. The concept introduced here provides a platform for non-invasive, patient-specific preoperative planning of the osteotomy for medial compartment knee osteoarthritis.

  4. A Non-Invasive Method for Detecting the Metabolic Stress Response in Rodents: Characterization and Disruption of the Circadian Corticosterone Rhythm

    PubMed Central

    Thanos, Panayotis K.; Cavigelli, Sonia A.; Michaelides, Michael; Olvet, Doreen M.; Patel, Ujval; Diep, Mai N.; Volkow, Nora D.

    2009-01-01

    1. Summary Plasma corticosterone (CORT) measures are a common procedure to detect stress responses in rodents. However, the procedure is invasive and can influence CORT levels, making it less than ideal for monitoring CORT circadian rhythms. In the current paper, we examined the applicability of a non-invasive fecal CORT metabolite measure to assess the circadian rhythm. We compared fecal CORT metabolite levels to circulating CORT levels, and analyzed change in the fecal circadian rhythm following an acute stressor (i.e. blood sampling by tail veil catheter). Fecal and blood samples were collected from male adolescent rats and analyzed for CORT metabolites and circulating CORT respectively. Fecal samples were collected hourly for 24 hours pre- and post-blood draw. On average, peak fecal CORT metabolite values occurred 7–9 hours after the plasma CORT peak and time-matched fecal CORT values were well correlated with plasma CORT. As a result of the rapid blood draw, fecal production and CORT levels were altered the next day. These results indicate fecal CORT metabolite measures can be used to assess conditions that disrupt the circadian CORT rhythm, and provide a method to measure long-term changes in CORT production. This can benefit research that requires long-term glucocorticoid assessment (e.g. stress mechanisms underlying health). PMID:18380537

  5. Non-invasive monitoring of reproductive and stress hormones in the endangered red panda (Ailurus fulgens fulgens).

    PubMed

    Beaulah Budithi, Neema Raja; Kumar, Vinod; Yalla, Suneel Kumar; Rai, Upashna; Umapathy, Govindhaswamy

    2016-09-01

    The red panda (Ailurus fulgens fulgens) is classified as endangered due to its declining population, habitat fragmentation and poaching. Efforts are being made to breed them in captivity as part of nationwide conservation breeding program. This study aimed to standardize Enzyme immunoassays (EIAs) to monitor reproductive (Progesterone metabolite, Testosterone) and stress hormone (Cortisol) in red panda. For this purpose, we collected 1471 faecal samples from four females and one male over a period of one year from Padmaja Naidu Himalayan Zoological Park, Darjeeling, India. HPLC confirmed the presence of immunoreactive 5α-pregnan-3α-ol-20-one, testosterone and cortisol metabolites in faecal samples. Using 5α-pregnan-3α-ol-20-one EIA, we were able to monitor reproduction and detect pregnancy in one of the females, which successfully conceived and delivered during the study period. We were also able to monitor testosterone and cortisol in faecal samples of the red panda. Faecal testosterone levels were found in higher concentration in breeding season than in non-breeding season. Faecal cortisol concentrations showed a negative relationship with ambient temperature and peaked during winter months in all animals. Standardization of EIAs and faecal hormone monitoring would facilitate red panda conservation breeding programs in India and elsewhere.

  6. The feasibility and applications of non-invasive cardiac output monitoring, thromboelastography and transit-time flow measurement in living-related renal transplantation surgery: results of a prospective pilot observational study

    PubMed Central

    2014-01-01

    Introduction Delayed graft function (DGF) remains a significant and detrimental postoperative phenomenon following living-related renal allograft transplantation, with a published incidence of up to 15%. Early therapeutic vasodilatory interventions have been shown to improve DGF, and modifications to immunosuppressive regimens may subsequently lessen its impact. This pilot study assesses the potential applicability of perioperative non-invasive cardiac output monitoring (NICOM), transit-time flow monitoring (TTFM) of the transplant renal artery and pre-/perioperative thromboelastography (TEG) in the early prediction of DGF and perioperative complications. Methods Ten consecutive living-related renal allograft recipients were studied. Non-invasive cardiac output monitoring commenced immediately following induction of anaesthesia and was maintained throughout the perioperative period. Doppler-based TTFM was performed during natural haemostatic pauses in the transplant surgery: immediately following graft reperfusion and following ureteric implantation. Central venous blood sampling for TEG was performed following induction of anaesthesia and during abdominal closure. Results A single incidence of DGF was seen within the studied cohort and one intra-operative (thrombotic) complication noted. NICOM confirmed a predictable trend of increased cardiac index (CI) following allograft reperfusion (mean CI - clamped: 3.17 ± 0.29 L/min/m2, post-reperfusion: 3.50 ± 0.35 L/min/m2; P < 0.05) mediated by a significant reduction in total peripheral resistance. Reduced TTFM at the point of allograft reperfusion (227 ml/min c.f. mean; 411 ml/min (95% CI: 358 to 465)) was identified in a subject who experienced intra-operative transplant renal artery thrombosis. TEG data exhibited significant reductions in clot lysis (LY30 (%): pre-op: 1.0 (0.29 to 1.71), post reperfusion 0.33 (0.15 to 0.80); P = 0.02) and a trend towards increased clot initiation following

  7. Evaluation of cardiac output in intensive care using a non-invasive arterial pulse contour technique (Nexfin(®)) compared with echocardiography.

    PubMed

    Taton, O; Fagnoul, D; De Backer, D; Vincent, J-L

    2013-09-01

    In this prospective study, cardiac output was measured in 38 intensive care unit patients before and after a fluid challenge, using both pulse contour analysis (Nexfin(®); BMEYE, Amsterdam, the Netherlands) and transthoracic echocardiography. The ability of the Nexfin device to detect significant changes in the velocity-time integral was evaluated. The pulse wave could not be detected by the Nexfin device in five patients (13%), leaving 33 patients for analysis. The Nexfin device adequately tracked changes in the velocity-time integral in 20 (61%) patients. Using a cut-off of a 10% increase in cardiac output estimated by the Nexfin or by echocardiography, the sensitivity of the Nexfin device to detect a response to fluid challenge was 47%, with specificity 81% and accuracy 64%. The percentage error between the Nexfin and echocardiography was 448%; lower limit of agreement -48% (95% CI -62 to -36%) and upper limit of agreement, 32% (95% CI 20-45%). We conclude that the Nexfin device does not adequately track changes in cardiac output in critically ill patients.

  8. The relationships between self-assessed habitual physical activity and non-invasive measures of cardiac autonomic modulation in young healthy volunteers.

    PubMed

    Sandercock, Gavin R H; Hardy-Shepherd, Darren; Nunan, David; Brodie, David

    2008-09-01

    Heart rate variability estimates cardiac autonomic modulation, but the relationship between habitual physical activity and heart rate variability remains unclear. The aims of this study were to compare RR-interval and heart rate variability indices in individuals of different habitual physical activity levels, and examine the relationship between habitual physical activity and heart rate variability. Ninety-two healthy volunteers (47 men, 45 women; mean age 23.1 years, s = 2.1) were divided into tertiles according to the Baecke Questionnaire score. Standard heart rate variability indices were derived from 5-min resting RR-interval recordings with paced respiration (0.25 Hz). Between-group differences and the relationship between habitual physical activity and heart rate variability were assessed. More active participants (tertiles 2-3) had longer RR-intervals than those in tertile 1 (P < 0.05). Participants in tertile 2 had higher root mean squared differences of successive normal RR-intervals than those in tertile 1 and a higher standard deviation of normal RR-intervals than those in tertiles 1 and 3. There was a positive linear relationship between habitual activity and RR-interval. Differing RR-interval lengths were found in subgroups of young individuals according to level of habitual physical activity. More active individuals showed resting bradycardia without evidence of enhanced cardiac parasympathetic modulation. The mechanism linking habitual physical activity and RR-interval length appears to be independent of physiological mechanisms that can be measured by heart rate variability.

  9. Speckle tracking echocardiography in the critically ill: enticing research with minimal clinical practicality or the answer to non-invasive cardiac assessment?

    PubMed

    Orde, S; Huang, S J; McLean, A S

    2016-09-01

    Echocardiography is developing rapidly. Speckle tracking echocardiography is the latest semi-automatic tool that has potential to quantitatively describe cardiac dysfunction that may be unrecognised by conventional echocardiography. It is a non-Doppler, angle-independent, feasible and reproducible method to evaluate myocardial function in both non-critically ill and critically ill populations. Increasingly it has become a standard measure of both left and right ventricle function in specific patient groups, e.g. chemotherapy-induced cardiomyopathy or pulmonary hypertension. To date there are few studies in the critically ill, predominantly in sepsis, yet all describe dysfunction beyond standard measures. Other areas of interest include heart-lung interactions, right ventricle function and twist and torsion of the heart. A word of caution is required, however, in that speckle tracking echocardiography is far from perfect and is more challenging, particularly in the critically ill, than implied by many published studies. It takes time to learn and perform and most values are not validated, particularly in the critically ill. We should be cautious in accepting that the latest software used in cardiology cohorts will automatically be the answer in the critically ill. Even with these limitations the technology is enticing and results fascinating. We are uncovering previously undescribed dysfunction and although it currently is essentially a research-based activity, there is great promise as a clinical tool as echocardiography analysis becomes more automated, and potentially speckle tracking echocardiography could help describe cardiac function in critical illness more accurately than is possible with current techniques.

  10. Usefulness of non-invasive measurement of cardiac output during sub-maximal exercise to predict outcome in patients with chronic heart failure.

    PubMed

    Goda, Ayumi; Lang, Chim C; Williams, Paula; Jones, Margaret; Farr, Mary Jane; Mancini, Donna M

    2009-12-01

    Peak oxygen consumption (Vo(2)) is a powerful prognostic predictor of survival in patients with chronic heart failure (CHF) because it provides an indirect assessment of a patient's ability to increase cardiac output (CO). However, many patients with CHF who undergo cardiopulmonary exercise testing are unable to perform maximal exercise. New metabolic carts coupled with the inert gas rebreathing technique provide a noninvasive measurement of CO. Whether the noninvasive measurement of CO at a fixed submaximal workload can predict outcome is unknown. This study's population comprised 259 patients (mean age 54 +/- 14 years, mean left ventricular ejection fraction 27 +/- 14%) with CHF who underwent symptom-limited incremental cardiopulmonary exercise testing. Vo(2) and CO were measured at rest, at 25 W, and at peak exercise. Submaximal exercise was defined as <80% peak Vo(2). Among 259 patients, 145 had Vo(2) at 25 W <80% of peak. Vo(2) at 25 W averaged 9.3 +/- 1.8 ml/kg/min. This Vo(2) represented 62 +/- 11% of peak Vo(2), which averaged 15.4 +/- 4.4 ml/kg/min. Prospective follow-up averaged 521 +/- 337 days. In this cohort, there were 15 outcome events (death, urgent heart transplantation, or implantation of a left ventricular assist device as a bridge to transplantation). On univariate Cox hazard analysis, CO at 25 W (hazard ratio 0.64, 95% confidence interval 0.48 to 0.84, p = 0.002) was found to be significant predictor of events of outcome. In conclusion, CO at 25 W measured noninvasively during submaximal exercise may have potential value as a predictor of outcomes in patients with CHF.

  11. Thallium cardiac stressing by esophageal pacing

    SciTech Connect

    Allen, M.L.; Vacek, J.L.; Preston, D.F.; Robinson, R.G.; Feldkamp, M.J. )

    1989-09-01

    Forty-three patients were examined with the transesophageal pacing method of cardiac stressing and thallium imaging. Transesophageal cardiac pacing, using a pill electrode or a permanent pacemaker lead, is a safe alternative for patients who are physically unable to exercise. Prior studies suggest that transvenous right atrial pacing with thallium injection is equivalent to physical exercise thallium studies in the detection of coronary artery disease. The esophageal pacing bipolar electrode similarly increases heart rate without the necessity of transvenous pacing or fluoroscopy and without the adverse side effects often seen when using pharmacologic stressing agents (i.e., dipyridamole). The results compare well with cardiac catheterization, echocardiographic, and electrocardiographic results. Cardiac paced stress testing requires no sedation, is performed on an out-patient basis, and causes little if any discomfort for the patient.

  12. Non-invasive hemoglobin monitoring.

    PubMed

    Joseph, Bellal; Haider, Ansab; Rhee, Peter

    2016-09-01

    Technology has transformed the practice of medicine and surgery in particular over the last several decades. This change in practice has allowed diagnostic and therapeutic tests to be performed less invasively. Hemoglobin monitoring remains one of the most commonly performed diagnostic tests in the United States. Recently, non-invasive hemoglobin monitoring technology has gained popularity. The aim of this article is to review the principles of how this technology works, pros and cons, and the implications of non-invasive hemoglobin technology particularly in trauma surgery.

  13. The timing of onset of mechanical systole and diastole in reference to the QRS-T complex: a study to determine performance criteria for a non-invasive diastolic timed vibration massage system in treatment of potentially unstable cardiac disorders.

    PubMed

    Gill, Harjit; Hoffmann, Andrew

    2010-12-01

    Our institution is in development of a low frequency, non-invasive Diastolic Timed Vibrator (DTV) for use in emergency treatment of ST Elevation Myocardial Infarction (STEMI). It is preferable to avoid vibration emissions during the IsoVolumetric Contraction Period (IVCP) and at least the majority of mechanical systole thereafter, as systolic vibration may cause a negative inotropic effect in the ischemic heart. Furthermore diastolic vibration should preferably include the IsoVolumetric Relaxation Period (IVRP) which has been shown in clinical studies to improve cardiac performance and enhance coronary flow. Electrocardiographic (ECG) monitoring can be used to enable diastolic tracking, however, the timing of the phases of the cardiac cycle in relation to the ECG waveform must first be verified. The objective of this study was therefore to determine timing of onset of mechanical systole and diastole in reference to the QRS-T Complex. One hundred and twenty-three adult echocardiographic studies were assessed for the point of mitral and aortic valve closure in relation to the QRS complex and T wave in a representative population. We found that onset of mechanical systole occurred on and usually shortly after the peak of a first dominant QRS complex deflection, and onset of diastole occurred at the earliest on and most commonly beyond the peak or midpoint of the T wave. A DTV should ideally be able to stop vibrating on or before the peak of the first dominant deflection of a QRS complex, and begin vibrating near the peak of the T wave. Given early detection of ventricular depolarization can occur 10-20 ms prior to R wave peak, it is proposed that a DTV should preferably be able to stop vibrating within 10 ms of a triggered stop command. Onset of vibration during peak of T wave could be approximated by a rate adapted Q-T interval regression equation, and then fine tuned by manual adjustment during therapy.

  14. [Non-invasive ventilation and acute cardiogenic pulmonary oedema].

    PubMed

    Golmard, Céline

    2015-11-01

    Non-invasive ventilation is an integral part of therapies used in patients presenting acute cardiogenic pulmonary oedema. In cardiac intensive care, these patients are treated by teams trained and practised in this technique. The nurses play a central role in the support and monitoring of the patients.

  15. Acute emotional stress and cardiac arrhythmias.

    PubMed

    Ziegelstein, Roy C

    2007-07-18

    Episodes of acute emotional stress can have significant adverse effects on the heart. Acute emotional stress can produce left ventricular contractile dysfunction, myocardial ischemia, or disturbances of cardiac rhythm. Although these abnormalities are often only transient, their consequences can be gravely damaging and sometimes fatal. Despite the many descriptions of catastrophic cardiovascular events in the setting of acute emotional stress, the anatomical substrate and physiological pathways by which emotional stress triggers cardiovascular events are only now being characterized, aided by the advent of functional neuroimaging. Recent evidence indicates that asymmetric brain activity is particularly important in making the heart more susceptible to ventricular arrhythmias. Lateralization of cerebral activity during emotional stress may stimulate the heart asymmetrically and produce areas of inhomogeneous repolarization that create electrical instability and facilitate the development of cardiac arrhythmias. Patients with ischemic heart disease who survive an episode of sudden cardiac death in the setting of acute emotional stress should receive a beta-blocker. Nonpharmacological approaches to manage emotional stress in patients with and without coronary artery disease, including social support, relaxation therapy, yoga, meditation, controlled slow breathing, and biofeedback, are also appropriate to consider and merit additional investigation in randomized trials.

  16. Stress imaging in congenital cardiac disease.

    PubMed

    Robbers-Visser, Daniëlle; Luijnenburg, Saskia E; van den Berg, Jochem; Moelker, Adriaan; Helbing, Willem A

    2009-12-01

    In patients with coronary arterial disease, stress imaging is able to demonstrate abnormalities in the motion of the ventricular walls, and abnormalities in coronary arterial perfusion not apparent at rest. It can also provide information on prognostic factors. In patients with congenitally malformed hearts, stress imaging is used to determine contractile reserve, abnormalities of mural motion, and global systolic function, but also to assess diastolic and vascular function. In most of these patients, stress is usually induced using pharmacological agents, mainly dobutamine given in varying doses. The clinical usefulness of abnormal responses to the stress induced in such patients has to be addressed in follow-up studies. The abnormal stress might serve as surrogate endpoints, predicting primary endpoints at an early stage, which are useful for stratification of risk in this population of growing patients. We review here the stress imaging studies performed to date in patients with congenitally malformed hearts, with a special emphasis on echocardiography and cardiac magnetic resonance imaging.

  17. Congenital coronary artery anomalies silent until geriatric age: non-invasive assessment, angiography tips, and treatment

    PubMed Central

    Rigatelli, Gianluca; Dell'Avvocata, Fabio; Van Tan, Nguyen; Daggubati, Rames; Nanijundappa, Aravinda

    2015-01-01

    Coronary artery anomalies (CAAs) may be discovered more often as incidental findings during the normal diagnostic process for other cardiac diseases or less frequently on the basis of manifestations of myocardial ischemia. The cardiovascular professional may be involved in their angiographic diagnosis, functional assessment and eventual endovascular treatment. A complete angiographic definition is mandatory in order to understand the functional effects and plan any intervention in CAAs: computed tomography and magnetic resonance imaging are useful non-invasive tools to detect three-dimensional morphology of the anomalies and its relationships with contiguous cardiac structures, whereas coronary arteriography remains the gold standard for a definitive anatomic picture. A practical idea of the possible functional significance is mandatory for deciding how to manage CAAs: non-invasive stress tests and in particular the invasive pharmacological stress tests with or without intravascular ultrasound monitoring can assess correctly the functional significance of the most CAAs. Finally, the knowledge of the particular endovascular techniques and material is of paramount importance for achieving technical and clinical success. CAAs represent a complex issue, which rarely involve the cardiovascular professional at different levels. A timely practical knowledge of the main issues regarding CAAs is important in the management of such entities. PMID:25678906

  18. Non-invasive glucose monitor

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2001-01-01

    A non-invasive method for determining blood level of an analyte of interest, such as glucose, comprises: generating an excitation laser beam (e.g., at a wavelength of 700 to 900 nanometers); focusing the excitation laser beam into the anterior chamber of an eye of the subject so that aqueous humor in the anterior chamber is illuminated; detecting (preferably confocally detecting) a Raman spectrum from the illuminated aqueous humor; and then determining the blood glucose level (or the level of another analyte of interest) for the subject from the Raman spectrum. Preferably, the detecting step is followed by the step of subtracting a confounding fluorescence spectrum from the Raman spectrum to produce a difference spectrum; and determining the blood level of the analyte of interest for the subject from that difference spectrum, preferably using linear or nonlinear multivariate analysis such as partial least squares analysis. Apparatus for carrying out the foregoing method is also disclosed.

  19. Phospholemman: a novel cardiac stress protein.

    PubMed

    Cheung, Joseph Y; Zhang, Xue-Qian; Song, Jianliang; Gao, Erhe; Rabinowitz, Joseph E; Chan, Tung O; Wang, Jufang

    2010-08-01

    Phospholemman (PLM), a member of the FXYD family of regulators of ion transport, is a major sarcolemmal substrate for protein kinases A and C in cardiac and skeletal muscle. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. Functionally, when phosphorylated at serine(68), PLM stimulates Na(+)-K(+)-ATPase but inhibits Na(+)/Ca(2+) exchanger in cardiac myocytes. In heterologous expression systems, PLM modulates the gating of cardiac L-type Ca(2+) channel. Therefore, PLM occupies a key modulatory role in intracellular Na(+) and Ca(2+) homeostasis and is intimately involved in regulation of excitation-contraction (EC) coupling. Genetic ablation of PLM results in a slight increase in baseline cardiac contractility and prolongation of action potential duration. When hearts are subjected to catecholamine stress, PLM minimizes the risks of arrhythmogenesis by reducing Na(+) overload and simultaneously preserves inotropy by inhibiting Na(+)/Ca(2+) exchanger. In heart failure, both expression and phosphorylation state of PLM are altered and may partly account for abnormalities in EC coupling. The unique role of PLM in regulation of Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and potentially L-type Ca(2+) channel in the heart, together with the changes in its expression and phosphorylation in heart failure, make PLM a rational and novel target for development of drugs in our armamentarium against heart failure. Clin Trans Sci 2010; Volume 3: 189-196.

  20. [Non invasive quantification of the parietal systolic stress of the left ventricle in patients with heart failure and its clinical application].

    PubMed

    Guadalajara Boo, José Fernando; González Zárate, Jaime; Bucio Reta, Eduardo; Pérez, Patricia; Cué Carpio, Ramón José

    2007-01-01

    The purpose of this study is to calculate non invasivelly left ventricular systolic wall stress by echocardiography in patients with primary heart failure, and compare the results with those obtained in parients with overloaded heart failure, diastolic dysfunction by Inapropiatte hypertrophy, with normal ejection fraction and people with normal heart, there stablish the value of the results in clinical settings. We studied 33 patients with heart failure by dilated cardiomyopathy. There was no significant association between the systolic wall stress and the ejection fraction, fractional shortening, dp/dt or left ventricular mass in this group of study. There was a significant association between systolic h/r ratio and the systolic wall stress. This study shows that in primary heart failure the afterload increases and has inverse relationship with ejection fraction (r = 0.86); but, when heart failure obey to an excessive overload exists an exquisite inverse relationship between systolic wall stress and ejection fraction (r = 0.93). The excessive hypertrophy (Inappropriate) reduces the systolic wall stress but causes diastolic dysfunction. The increase of systolic wall stress in Aortic regurgitation with normal ventricular performance is responsible of adequate left ventricular hypertrophy, by other means, in mitral insufficiency the presence of low or normal systolic wall The purpose of this study is to calculate non invasivelly left ventricular systolic wall stress by echocardiography in patients with primary heart failure, and compare the results with those obtained in parients with overloaded heart failure, diastolic dysfunction by Inapropiatte hypertrophy, with normal ejection fraction and people with normal heart, there stablish the value of the results in clinical settings. We studied 33 patients with heart failure by dilated cardiomyopathy. There was no significant association between the systolic wall stress and the ejection fraction, fractional shortening

  1. Non-invasive assessment of animal exercise stress: real-time PCR of GLUT4, COX2, SOD1 and HSP70 in avalanche military dog saliva.

    PubMed

    Diverio, S; Guelfi, G; Barbato, O; Di Mari, W; Egidi, M G; Santoro, M M

    2015-01-01

    Exercise has been shown to increase mRNA expression of a growing number of genes. The aim of this study was to assess if mRNA expression of the metabolism- and oxidative stress-related genes GLUT4 (glucose transporter 4), COX2 (cyclooxygenase 2), SOD1 (superoxide dismutase 1) and HSP70 (heat shock protein 70) in saliva changes following acute exercise stress in dogs. For this purpose, 12 avalanche dogs of the Italian Military Force Guardia di Finanza were monitored during simulation of a search for a buried person in an artificial avalanche area. Rectal temperature (RT) and saliva samples were collected the day before the trial (T0), immediately after the descent from a helicopter at the onset of a simulated avalanche search and rescue operation (T1), after the discovery of the buried person (T2) and 2 h later (T3). Expressions of GLUT4, SOD1, COX2 and HSP70 were measured by real-time PCR. The simulated avalanche search and rescue operation was shown to exert a significant effect on RT, as well as on the expression of all metabolism- and oxidative stress-related genes investigated, which peaked at T2. The observed expression patterns indicate an acute exercise stress-induced upregulation, as confirmed by the reductions in expression at T3. Moreover, our findings indicate that saliva is useful for assessing metabolism- and oxidative stress-related genes without the need for restraint, which could affect working dog performance.

  2. Non-Invasive Glucose Measurement

    NASA Astrophysics Data System (ADS)

    Blakley, Daniel

    2010-10-01

    There are two little words, when taken together have great implications: ``What IF'' In the US alone, there are millions who are burdened with diabetes and who must maintain their glucose levels by taking blood samples and having it analyzed. Even though this procedure has improved over time, still it is very intrusive and is a burden to many that must live with it. What if it were not necessary? Although it is current practice to measure glucose levels invasively (using blood samples), it may be possible to measure glucose non-invasively. Although several companies around the world have invested millions of dollars to address this problem, none have been successful thus far. However, there are many methods that hold a potential and many approaches that have not yet been explored. We are working on a review of what has been approached thus far and are entertaining proposals for a combined interdisciplinary approach which combines expertise from bioengineering, physics, and biology. We hope to learn from the unsuccessful attempts of others whilst employing innovative new approaches to this problem.

  3. Oxidative stress response in the skin mucus layer of Goodea gracilis (Hubbs and Turner, 1939) exposed to crude oil: A non-invasive approach.

    PubMed

    Dzul-Caamal, Ricardo; Salazar-Coria, Lucia; Olivares-Rubio, Hugo F; Rocha-Gómez, Maria Alejandra; Girón-Pérez, Manuel Iván; Vega-López, Armando

    2016-10-01

    The skin of the fish is the foremost target of oxidative stress due to the generation of Reactive Oxygen Species (ROS) originated in the environment and in the skin itself. In this study, a non-destructive assay was developed to evaluate the effects of crude oil (0.0001-0.1mg/L, 96h) on oxidative stress response in the Skin Mucus Layer (SML) of the dusky splitfin goodeid (Goodea gracilis). The response in the SML was compared with recognized target organs through the Integrated Biomarker Response (IBRv2) and a slight addition to the method was proposed. Crude oil was extremely toxic and elicited a clear induction of ROS in the SML, as in the brain, liver and muscle. By the exposure to crude, a significant change in the activities of Superoxide Dismutase (SOD), Catalase (CAT), Glutathione Peroxidase (GPx) as well as on lipid peroxidation (TBARS) and carbonyl protein (RCO) levels was detected. Also, increases in the activity of EROD were found. The general IBRv2 proposed in this study (gIBRv2) showed that oil causes the higher oxidative response in the SML (60.049) under different concentrations of petroleum, which was greater in the brain (56.749), muscle (56.561) and liver (55.775). The results of the study revealed an organ-specific antioxidant defense response that was dependent on the load of petroleum. These results contributed to the understanding of the complexity of oxidative stress response in fish exposed to crude oil using the Skin Mucus Layer as a target for environmental monitoring studies.

  4. Non-invasive sensing for food reassurance.

    PubMed

    Xiaobo, Zou; Xiaowei, Huang; Povey, Malcolm

    2016-03-07

    Consumers and governments are increasingly interested in the safety, authenticity and quality of food commodities. This has driven attention towards non-invasive sensing techniques used for rapid analyzing these commodities. This paper provides an overview of the state of the art in, and available alternatives for, food assurance based on non-invasive sensing techniques. The main food quality traits of interest using non-invasive sensing techniques are sensory characteristics, chemical composition, physicochemical properties, health-protecting properties, nutritional characteristics and safety. A wide range of non-invasive sensing techniques, from optical, acoustical, electrical, to nuclear magnetic, X-ray, biosensor, microwave and terahertz, are organized according to physical principle. Some of these techniques are now in a period of transition between experimental and applied utilization and several sensors and instruments are reviewed. With continued innovation and attention to key challenges, such non-invasive sensors and biosensors are expected to open up new exciting avenues in the field of portable and wearable wireless sensing devices and connecting with mobile networks, thus finding considerable use in a wide range of food assurance applications. The need for an appropriate regulatory framework is emphasized which acts to exclude unwanted components in foods and includes needed components, with sensors as part of a reassurance framework supporting regulation and food chain management. The integration of these sensor modalities into a single technological and commercial platform offers an opportunity for a paradigm shift in food reassurance.

  5. Non-invasive monitoring of physiological stress in the Western lowland gorilla (Gorilla gorilla gorilla): validation of a fecal glucocorticoid assay and methods for practical application in the field.

    PubMed

    Shutt, Kathryn; Setchell, Joanna M; Heistermann, Michael

    2012-11-01

    variation in FGCMs in samples from wild gorillas. Our study highlights the importance of thorough biological and immunological validation of FGCM assays, and presents validated, practical methods for the application of non-invasive adrenocortical monitoring techniques to field conservation contexts where it is crucially needed.

  6. Fibroblast growth factor 21 is induced upon cardiac stress and alters cardiac lipid homeostasis

    PubMed Central

    Brahma, Manoja K.; Adam, Rene C.; Pollak, Nina M.; Jaeger, Doris; Zierler, Kathrin A.; Pöcher, Nadja; Schreiber, Renate; Romauch, Matthias; Moustafa, Tarek; Eder, Sandra; Ruelicke, Thomas; Preiss-Landl, Karina; Lass, Achim; Zechner, Rudolf; Haemmerle, Guenter

    2014-01-01

    Fibroblast growth factor 21 (FGF21) is a PPARα-regulated gene elucidated in the liver of PPARα-deficient mice or PPARα agonist-treated mice. Mice globally lacking adipose triglyceride lipase (ATGL) exhibit a marked defect in TG catabolism associated with impaired PPARα-activated gene expression in the heart and liver, including a drastic reduction in hepatic FGF21 mRNA expression. Here we show that FGF21 mRNA expression is markedly increased in the heart of ATGL-deficient mice accompanied by elevated expression of endoplasmic reticulum (ER) stress markers, which can be reversed by reconstitution of ATGL expression in cardiac muscle. In line with this assumption, the induction of ER stress increases FGF21 mRNA expression in H9C2 cardiomyotubes. Cardiac FGF21 expression was also induced upon fasting of healthy mice, implicating a role of FGF21 in cardiac energy metabolism. To address this question, we generated and characterized mice with cardiac-specific overexpression of FGF21 (CM-Fgf21). FGF21 was efficiently secreted from cardiomyocytes of CM-Fgf21 mice, which moderately affected cardiac TG homeostasis, indicating a role for FGF21 in cardiac energy metabolism. Together, our results show that FGF21 expression is activated upon cardiac ER stress linked to defective lipolysis and that a persistent increase in circulating FGF21 levels interferes with cardiac and whole body energy homeostasis. PMID:25176985

  7. Non invasive assessment of the human tear film dynamics.

    PubMed

    Ring, M H; Rabensteiner, D F; Horwath-Winter, J; Boldin, I; Schrödl, F; Reitsamer, H; Haslwanter, T

    2015-11-01

    Dry eye disease, or keratoconjunctivitis sicca, is a multifactorial syndrome with altered tear film homeostasis leading to ocular irritations. These alterations cause discomfort and stress for the patient, but only a few objective parameters allow for proper differential diagnosis into different subtypes of this condition. The mostly invasively performed standard assessment procedures for tear film diagnosis are manifold, but often correlate quite poorly with the subjectively reported symptoms. Due to the inherent limitations, e.g. the subjectivity of the commonly performed invasive tests, a number of devices have been developed to assess the human tear film non-invasively. Since the production, delivery, distribution and drainage of the tear film is a dynamic process, we have focused our review on non-invasive methods which are capable of continuous or repetitive observations of the tear film during an inter-blink interval. These dynamic methods include (1) Interferometry, (2) Pattern Projection, (3) Aberrometry, (4) Thermography; and (5) Evaporimetry. These techniques are discussed with respect to their diagnostic value, both for screening and differential diagnostic of Dry Eye Disease. Many of the parameters obtained from these tests have been shown to have the potential to reliably discriminate patients from healthy subjects, especially when the tests are performed automatically and objectively. The differentiation into subtypes based solely on a single, dynamic parameter may not be feasible, but the combination of non-invasively performed procedures may provide good discrimination results.

  8. The role of cardiac sympathetic innervation and skin thermoreceptors on cardiac responses during heat stress

    PubMed Central

    Umemoto, Yasunori; Kinoshita, Tokio; Kouda, Ken; Ito, Tomoyuki; Nakamura, Takeshi; Crandall, Craig G.; Tajima, Fumihiro

    2015-01-01

    The mechanism(s) for the changes in cardiac function during heat stress remain unknown. This study tested two unique hypotheses. First, sympathetic innervation to the heart is required for increases in cardiac systolic function during heat stress. This was accomplished by comparing responses during heat stress between paraplegics versus tetraplegics, with tetraplegics having reduced/absent cardiac sympathetic innervation. Second, stimulation of skin thermoreceptors contributes to cardiovascular adjustments that occur during heat stress in humans. This was accomplished by comparing responses during leg only heating between paraplegic versus able-bodied individuals. Nine healthy able-bodied, nine paraplegics, and eight tetraplegics participated in this study. Lower body (i.e., nonsensed area for para/tetraplegics) was heated until esophageal temperature had increased by ∼1.0°C. Echocardiographic indexes of diastolic and systolic function were performed before and at the end of heat stress. The heat stress increased cardiac output in all groups, but the magnitude of this increase was attenuated in the tetraplegics relative to the able-bodied (1.3 ± 0.4 vs. 2.3 ± 1.0 l/min; P < 0.05). Diastolic function was maintained in all groups. Indexes of left atrial and ventricular systolic function were enhanced in the able-bodied, but did not change in tetraplegics, while these changes in paraplegics were attenuated relative to the able-bodied. These data suggest that the cardiac sympathetic innervation is required to achieve normal increases in cardiac systolic function during heat stress but not required to maintain diastolic function during this exposure. Second, elevated systolic function during heat stress primarily occurs as a result of increases in internal temperature, although stimulation of skin thermoreceptors may contribute. PMID:25795714

  9. Ultrasonic non invasive techniques for microbiological instrumentation

    NASA Astrophysics Data System (ADS)

    Elvira, L.; Sierra, C.; Galán, B.; Resa, P.

    2010-01-01

    Non invasive techniques based on ultrasounds have advantageous features to study, characterize and monitor microbiological and enzymatic reactions. These processes may change the sound speed, viscosity or particle distribution size of the medium where they take place, which makes possible their analysis using ultrasonic techniques. In this work, two different systems for the analysis of microbiological liquid media based on ultrasounds are presented. In first place, an industrial application based on an ultrasonic monitoring technique for microbiological growth detection in milk is shown. Such a system may improve the quality control strategies in food production factories, being able to decrease the time required to detect possible contaminations in packed products. Secondly, a study about the growing of the Escherichia coli DH5 α in different conditions is presented. It is shown that the use of ultrasonic non invasive characterization techniques in combination with other conventional measurements like optical density provides complementary information about the metabolism of these bacteria.

  10. [Non-invasive assessment of liver fibrosis].

    PubMed

    Cohen-Ezra, Oranit; Ben-Ari, Ziv

    2015-03-01

    Chronic liver diseases represent a major public health problem, accounting for significant morbidity and mortality worldwide. Prognosis and management of chronic liver diseases depend on the amount of liver fibrosis. Liver biopsy has long remained the gold standard for assessment of liver fibrosis. Liver biopsy is an invasive procedure with associated morbidity, it is rarely the cause for mortality, and has a few limitations. During the past two decades, in an attempt to overcome the limitations of liver biopsy, non-invasive methods for the evaluation of liver fibrosis have been developed, mainly in the field of viral hepatitis. This review will focus on different methods available for non-invasive evaluation of liver fibrosis including a biological approach which quantifies serum levels of biomarkers of fibrosis and physical techniques which measure liver stiffness by transient elastography, ultrasound or magnetic resonance based elastography, their accuracy, advantages and disadvantages.

  11. The Influence of Cardiac Risk Factor Burden on Cardiac Stress Test Outcomes

    PubMed Central

    Schrock, Jon W.; Li, Morgan; Orazulike, Chidubem; Emerman, Charles L.

    2011-01-01

    Background Chest pain is the most common admission diagnosis for observation unit patients. These patients often undergo cardiac stress testing to further risk stratify for coronary artery disease (CAD). The decision of whom to stress is currently based on clinical judgment. We sought to determine the influence of cardiac risk factor burden on cardiac stress test outcome for patients tested from an observation unit, inpatient or outpatient setting. Methods We performed a retrospective observational cohort study for all patients undergoing stress testing in our institution from June 2006 through July 2007. Cardiac risk factors were collected at the time of stress testing. Risk factors were evaluated in a summative fashion using multivariate regression adjusting for age and known coronary artery disease. The model was tested for goodness of fit and collinearity and the c statistic was calculated using the receiver operating curve. Results A total of 4026 subjects were included for analysis of which 22% had known CAD. The rates of positive outcome were 89 (12.0%), 95 (12.6%), and 343 (16.9%) for the OU, outpatients, and hospitalized patients respectively. While the odds of a positive test outcome increased for additional cardiac risk factors, ROC curve analysis indicates that simply adding the number of risk factors does not add significant diagnostic value. Hospitalized patients were more likely to have a positive stress test, OR 1.41 (1.10 - 1.81). Conclusions Our study does not support basing the decision to perform a stress test on the number of cardiac risk factors.

  12. Relationships Among Non-Invasive Predictors of Sudden Cardiac Death During Mental Stress and Exercise In Coronary Artery Disease Patients With Known Arrhythmic Vulnerability

    DTIC Science & Technology

    2009-12-16

    common symptom of an acute myocardial ischemia is pain in the chest region or angina pectoris . Myocardial infarction is a prolonged ischemic event...CVD is high based on symptom presentation (e.g. angina pectoris ) the ST segment depression is much more likely to be a good indicator of CVD and will...adverse coronary events, such as angina pectoris , MI, and coronary death, in this asymptomatic population (RR = 2.73, p = .04) (Rywik, et al., 2002). In

  13. Instrumentation for Non-Invasive Assessment of Cardiovascular Regulation

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J.

    1999-01-01

    It is critically important to be able to assess alterations in cardiovascular regulation during and after space flight. We propose to develop an instrument for the non-invasive assessment of such alterations that can be used on the ground and potentially during space flight. This instrumentation would be used by the Cardiovascular Alterations Team at multiple sites for the study of the effects of space flight on the cardiovascular system and the evaluation of countermeasures. In particular, the Cardiovascular Alterations Team will use this instrumentation in conjunction with ground-based human bed-rest studies and during application of acute stresses e.g., tilt, lower body negative pressure, and exercise. In future studies, the Cardiovascular Alterations Team anticipates using this instrumentation to study astronauts before and after space flight and ultimately, during space flight. The instrumentation may also be used by the Bone Demineralization/Calcium Metabolism Team, the Neurovestibular Team and the Human Performance Factors, Sleep and Chronobiology Team to measure changes in autonomic nervous function. The instrumentation will be based on a powerful new technology - cardiovascular system identification (CSI) - which has been developed in our laboratory. CSI provides a non-invasive approach for the study of alterations in cardiovascular regulation. This approach involves the analysis of second-to-second fluctuations in physiologic signals such as heart rate and non-invasively measured arterial blood pressure in order to characterize quantitatively the physiologic mechanisms responsible for the couplings between these signals. Through the characterization of multiple physiologic mechanisms, CSI provides a closed-loop model of the cardiovascular regulatory state in an individual subject.

  14. Non-invasive methods for embryo selection

    PubMed Central

    Sallam, HN; Sallam, NH; Sallam, SH

    2016-01-01

    Abstract With the widespread use of assisted reproduction, a simple and practical method for embryo selection is needed to optimize the chances of pregnancy while diminishing the incidence of multiple pregnancy and its accompanying problems. Many non-invasive methods for embryo selection have been proposed and some are more promising than others. This review summarizes these methods and attempts to evaluate them in the light of the best currently available evidence and to find out whether any of them is ripe for replacing or supplementing the time-honored method of morphological assessment. PMID:27909565

  15. Non-Invasive Assessment of Susceptibility to Ventricular Arrhythmias During Simulated Microgravity

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J.

    1999-01-01

    cardiac susceptibility to ventricular arrhythmias in subjects exposed to simulated space flight in the Human Studies Core protocol being conducted by the Cardiovascular Alterations Team, which involves sixteen days .of bed rest. In particular, we are applying a powerful new non-invasive technology, developed in Professor Cohen's laboratory at MIT for the quantitative assessment of the risk of life-threatening ventricular arrhythmias. This technology involves the measurement of microvolt levels of T wave alternans (TWA) during exercise stress, and was recently granted approval by the Food and Drug Administration to be used for the clinical evaluation of patients suspected to be at risk of ventricular arrhythmias. In addition, we are obtaining 24 hour Holter monitoring (to detect non-sustained ventricular tachycardia and to assess heart rate variability). We are also conducting protocols to obtain these same measures on a monthly basis for up to four months in subjects in the Bone Demineralization/calcium Metaboloism Team's long term bed rest study.

  16. Non-invasive Evaluation for Epilepsy Surgery

    PubMed Central

    IWASAKI, Masaki; JIN, Kazutaka; NAKASATO, Nobukazu; TOMINAGA, Teiji

    2016-01-01

    Epilepsy surgery is aimed to remove the brain tissues that are indispensable for generating patient’s epileptic seizures. There are two purposes in the pre-operative evaluation: localization of the epileptogenic zone and localization of function. Surgery is planned to remove possible epileptogenic zone while preserving functional area. Since no single diagnostic modality is superior to others in identifying and localizing the epileptogenic zone, multiple non-invasive evaluations are performed to estimate the location of the epileptogenic zone after concordance between evaluations. Essential components of non-invasive pre-surgical evaluation of epilepsy include detailed clinical history, long-term video-electroencephalography monitoring, epilepsy-protocol magnetic resonance imaging (MRI), and neuropsychological testing. However, a significant portion of drug-resistant epilepsy is associated with no or subtle MRI lesions or with ambiguous electro-clinical signs. Additional evaluations including fluoro-deoxy glucose positron emission tomography (FDG-PET), magnetoencephalography and ictal single photon emission computed tomography can play critical roles in planning surgery. FDG-PET should be registered on three-dimensional MRI for better detection of focal cortical dysplasia. All diagnostic tools are complementary to each other in defining the epileptogenic zone, so that it is always important to reassess the data based on other results to pick up or confirm subtle abnormalities. PMID:27627857

  17. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias.

    PubMed

    Karagueuzian, Hrayr S; Nguyen, Thao P; Qu, Zhilin; Weiss, James N

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death.

  18. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias

    PubMed Central

    Karagueuzian, Hrayr S.; Nguyen, Thao P.; Qu, Zhilin; Weiss, James N.

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death. PMID:23423152

  19. Non-Invasive Measurement of Intracranial Pressure Pulsation using Ultrasound

    NASA Technical Reports Server (NTRS)

    Ueno, Toshiaki; Ballard, R. E.; Yost, W. T.; Hargens, A. R.

    1997-01-01

    Exposure to microgravity causes a cephalad fluid shift which may elevate intracranial pressure (ICP). Elevation in ICP may affect cerebral hemodynamics in astronauts during space flight. ICP is, however, a difficult parameter to measure due to the invasiveness of currently available techniques. We already reported our development of a non-invasive ultrasound device for measurement of ICP. We recently modified the device so that we might reproducibly estimate ICP changes in association with cardiac cycles. In the first experiment, we measured changes in cranial distance with the ultrasound device in cadavera while changing ICP by infusing saline into the lateral ventricle. In the second experiment, we measured changes in cranial distance in five healthy volunteers while placing them in 60 deg, 30 deg head-up tilt, supine, and 10 deg head-down tilt position. In the cadaver study, fast Fourier transformation revealed that cranial pulsation is clearly associated with ICP pulsation. The ratio of cranial distance and ICP pulsation is 1.3microns/mmHg. In the tilting study, the magnitudes of cranial pulsation are linearly correlated to tilt angles (r=0.87). The ultrasound device has sufficient sensitivity to detect cranial pulsation in association with cardiac cycles. By analyzing the magnitude of cranial pulsation, estimates of ICP during space flight are possible.

  20. Emerging technologies for non-invasive quantification of physiological oxygen transport in plants.

    PubMed

    Chaturvedi, P; Taguchi, M; Burrs, S L; Hauser, B A; Salim, W W A W; Claussen, J C; McLamore, E S

    2013-09-01

    Oxygen plays a critical role in plant metabolism, stress response/signaling, and adaptation to environmental changes (Lambers and Colmer, Plant Soil 274:7-15, 2005; Pitzschke et al., Antioxid Redox Signal 8:1757-1764, 2006; Van Breusegem et al., Plant Sci 161:405-414, 2001). Reactive oxygen species (ROS), by-products of various metabolic pathways in which oxygen is a key molecule, are produced during adaptation responses to environmental stress. While much is known about plant adaptation to stress (e.g., detoxifying enzymes, antioxidant production), the link between ROS metabolism, O2 transport, and stress response mechanisms is unknown. Thus, non-invasive technologies for measuring O2 are critical for understanding the link between physiological O2 transport and ROS signaling. New non-invasive technologies allow real-time measurement of O2 at the single cell and even organelle levels. This review briefly summarizes currently available (i.e., mainstream) technologies for measuring O2 and then introduces emerging technologies for measuring O2. Advanced techniques that provide the ability to non-invasively (i.e., non-destructively) measure O2 are highlighted. In the near future, these non-invasive sensors will facilitate novel experimentation that will allow plant physiologists to ask new hypothesis-driven research questions aimed at improving our understanding of physiological O2 transport.

  1. Tissue-Informative Mechanism for Wearable Non-invasive Continuous Blood Pressure Monitoring

    NASA Astrophysics Data System (ADS)

    Woo, Sung Hun; Choi, Yun Young; Kim, Dae Jung; Bien, Franklin; Kim, Jae Joon

    2014-10-01

    Accurate continuous direct measurement of the blood pressure is currently available thru direct invasive methods via intravascular needles, and is mostly limited to use during surgical procedures or in the intensive care unit (ICU). Non-invasive methods that are mostly based on auscultation or cuff oscillometric principles do provide relatively accurate measurement of blood pressure. However, they mostly involve physical inconveniences such as pressure or stress on the human body. Here, we introduce a new non-invasive mechanism of tissue-informative measurement, where an experimental phenomenon called subcutaneous tissue pressure equilibrium is revealed and related for application in detection of absolute blood pressure. A prototype was experimentally verified to provide an absolute blood pressure measurement by wearing a watch-type measurement module that does not cause any discomfort. This work is supposed to contribute remarkably to the advancement of continuous non-invasive mobile devices for 24-7 daily-life ambulatory blood-pressure monitoring.

  2. Implementation of non-invasive brain physiological monitoring concepts.

    PubMed

    Ragauskas, Arminas; Daubaris, Gediminas; Ragaisis, Vytautas; Petkus, Vytautas

    2003-10-01

    The paper presents innovative methods and technology for non-invasive intracranial hemodynamics monitoring based on the measurement of brain parenchyma acoustic properties. The clinical investigation of new technology shows the similarity between the invasively recorded intracranial pressure (ICP) and non-invasively recorded intracranial blood volume (IBV) pulse waves, slow waves and slow trends under intensive care unit (ICU) conditions. Also, the applicability of the non-invasive IBV slow wave monitoring technique for cerebrovascular autoregulation non-invasive long-term monitoring is demonstrated by theoretical and experimental studies.

  3. Long-term non-invasive ventilation in children.

    PubMed

    Amaddeo, Alessandro; Frapin, Annick; Fauroux, Brigitte

    2016-12-01

    Use of long-term non-invasive ventilation is increasing exponentially worldwide in children of all ages. The treatment entails delivery of ventilatory assistance through a non-invasive interface. Indications for use of non-invasive ventilation include conditions that affect normal respiratory balance (eg, those associated with dysfunction of the central drive or respiratory muscles) and disorders characterised by an increase in respiratory load (eg, obstructive airway or lung diseases). The type of non-invasive ventilation used depends on the pathophysiological features of the respiratory failure. For example, non-invasive ventilation will need to either replace central drive if the disorder is characterised by an abnormal central drive or substitute for the respiratory muscles if the condition is associated with respiratory muscle weakness. Non-invasive ventilation might also need to unload the respiratory muscles in case of an increase in respiratory load, as seen in upper airway obstruction and some lung diseases. Technical aspects are also important when choosing non-invasive ventilation-eg, appropriate interface and device. The great heterogeneity of disorders, age ranges of affected children, prognoses, and outcomes of patients needing long-term non-invasive ventilation underline the need for management by skilled multidisciplinary centres with technical competence in paediatric non-invasive ventilation and expertise in sleep studies and therapeutic education.

  4. Non-invasive quick diagnosis of cardiovascular problems from visible and invisible abnormal changes with increased cardiac troponin I appearing on cardiovascular representation areas of the eyebrows, left upper lip, etc. of the face & hands: beneficial manual stimulation of hands for acute anginal chest pain, and important factors in safe, effective treatment.

    PubMed

    Omura, Yoshiaki; Jones, Marilyn K; Duvvi, Harsha; Shimotsuura, Yasuhiro; Ohki, Motomu; Rodriques, Aaron

    2014-01-01

    Our previous study indicated that there are at least 7 cardiovascular representation areas on the face, including the "Eyebrows", both sides of the "Nose", "Lelt Upper Lip" and the "Outside of the corner of both sides of the mouth," in addition to 2 areas in each hand. When there are cardiovascular problems, some of the heart representation areas of these areas often show the following changes: 1) Most distinctive visible changes such as the initial whitening with or without long white hair, then hair loss and complete disappearance of the hairs of the heart representation area of "Eyebrows" 2) Invisible biochemical changes that happen in heart representation areas at the "Left Upper Lips", 3) "Nose" below eye level as well as 4) "3rd segment of Middle Finger of Hands." Most distinctive visible & invisible changes are found in heart representation areas on the "Eyebrow", located nearest to the midline of face, where the color of the hairs becomes white compared with the rest of the Eyebrow. Then the cardiovascular problem advances, and hair starts disappearing. When there are no hairs at the heart representation areas of the Eyebrow, usually Cardiac Troponin I is increased to a very serious, abnormal high value. Most of the cardiovascular representation areas of the face show, regardless of presence or absence of visible change. When there is a cardiovascular problem, not only simple Bi-Digital O-Ring Test can detect without using any instrument in several minutes but also, corresponding biochemical changes of abnormally increased Cardiac Troponin I level can often be detected non-invasively from these Organ Representation Areas of Face & Hands, although changes in Eyebrows, L-Upper Lip & 3rd segment of middle fingers are clinically the most reliable changes & easy to identify the locations. Manual Stimulation of Hand's heart representation areas often eliminated acute anginal chest pain before medical help became available. Important factors for safe, effective

  5. Geraniol alleviates diabetic cardiac complications: Effect on cardiac ischemia and oxidative stress.

    PubMed

    El-Bassossy, Hany M; Ghaleb, Hanna; Elberry, Ahmed A; Balamash, Khadijah S; Ghareib, Salah A; Azhar, Ahmad; Banjar, Zainy

    2017-04-01

    The present study was planned to assess the possible protective effect of geraniol on cardiovascular complications in an animal model with diabetes. Diabetes was induced in rats by a single streptozotocin injection. In the treated group, geraniol (150mgkg(-1)day(-1)) was administered orally starting from the 15th day after induction of diabetes, and ending after 7 weeks; diabetic control rats were given vehicle for the same period. At the end of the study, cardiac contractility was assessed by using a Millar microtip catheter in anesthetised rats, and cardiac conductivity determined by a surface ECG. Serum levels of glucose, cholesterol, triglyceride and adiponectin as well as urine 8-isoprostane were determined. In addition, cardiac superoxide dismutase (SOD) and catalase activity were measured. Geraniol administration significantly alleviated the attenuated cardiac systolic function associated with diabetes as indicated by inhibiting the decrease in the rate of rise (dP/dtmax) in ventricular pressure and the increase in systolic duration observed in diabetic rats. In addition, geraniol alleviated impaired diastolic function as shown by inhibiting the decrease in the rate of fall (dP/dtmin) in ventricular pressure and increased isovolumic relaxation constant (Tau) observed in diabetic rats. ECG recordings showed that geraniol prevented any increase in QTc and T-peak-T-end intervals, and markers of LV ischemia and arrhythmogenesis, seen in diabetic animals. Geraniol suppressed the exaggerated oxidative stress as evidenced by preventing the increase in 8-isoprotane. In diabetic heart tissue, geraniol prevented the inhibition in catalase activity but did not affect the heart SOD. Geraniol partially reduced hyperglycemia, prevented the hypercholesterolemia, but did not affect the serum level of adiponectin in diabetic animals. Results obtained in this study suggest that geraniol provides a potent protective effect against cardiac dysfunction induced by diabetes. This

  6. Non-invasive diagnostic methods in dentistry

    NASA Astrophysics Data System (ADS)

    Todea, Carmen

    2016-03-01

    The paper, will present the most important non-invasive methods for diagnostic, in different fields of dentistry. Moreover, the laser-based methods will be emphasis. In orthodontics, 3D laser scanners are increasingly being used to establish database for normative population and cross-sectional growth changes but also to asses clinical outcomes in orthognatic surgical and non-surgical treatments. In prevention the main methods for diagnostic of demineralization and caries detection in early stages are represented by laser fluorescence - Quantitative Light Florescence (QLF); DiagnoDent-system-655nm; FOTI-Fiberoptic transillumination; DIFOTI-Digital Imaging Fiberoptic transillumination; and Optical Coherence Tomography (OCT). In odontology, Laser Doppler Flowmetry (LDF) is a noninvasive real time method used for determining the tooth vitality by monitoring the pulp microcirculation in traumatized teeth, fractured teeth, and teeth undergoing different conservative treatments. In periodontology, recently study shows the ability of LDF to evaluate the health of gingival tissue in periodontal tissue diseases but also after different periodontal treatments.

  7. Non-invasive physiology in conscious mice.

    PubMed

    Kale, Ajit; Amende, Ivo; Piskorski, Katrina; Chu, Victor; Otero, Jose M; Mueller, Peter; Hampton, Thomas G

    2004-06-01

    Linking gene defect to disease phenotypes in mice has become an essential step in the development of new drugs. Yet, many in vitro and in vivo assays require anaesthetic and surgery or do not reflect physiologically relevant phenomena. The effects of genes or diseases may only become apparent with stressors. Here, we apply non-invasive ECG monitoring and gait imaging systems to describe changes in the electrocardiogram and in gait dynamics resulting from a doubling of the ambulatory speed of mice. We found that B6C3H mice (n = 5) take 3.6 +/- 0.1 strides/second to walk 18cm/second and have a heart rate of 750 +/- 2bpm after 1 minute of walking at this speed. These mice significantly increase stride frequency to 5.2 +/- 0.1 strides/second in order to increase their speed to 36cm/second. The heart rate increased significantly (814 +/- 9bpm, p < 0.05) after trotting at the higher speed for 90 seconds, and the QRS interval duration significantly decreased (9.4 +/- 0.3ms vs. 10.4 +/- 0.3ms, p < 0.05). We discuss the application of the ECG screening and gait imaging systems to mouse models of Duchenne muscular dystrophy, Down syndrome and amyotrophic lateral sclerosis, diseases in humans that are known to affect the heart and neuromuscular systems.

  8. Myocardial Oxidative Stress in Infants Undergoing Cardiac Surgery.

    PubMed

    Sznycer-Taub, Nathaniel; Mackie, Stewart; Peng, Yun-Wen; Donohue, Janet; Yu, Sunkyung; Aiyagari, Ranjit; Charpie, John

    2016-04-01

    Cardiac surgery for congenital heart disease often necessitates a period of myocardial ischemia during cardiopulmonary bypass and cardioplegic arrest, followed by reperfusion after aortic cross-clamp removal. In experimental models, myocardial ischemia-reperfusion is associated with significant oxidative stress and ventricular dysfunction. A prospective observational study was conducted in infants (<1 year) who underwent elective surgical repair of a ventricular septal defect (VSD) or tetralogy of Fallot (TOF). Blood samples were drawn following anesthetic induction (baseline) and directly from the coronary sinus at 1, 3, 5, and 10 min following aortic cross-clamp removal. Samples were analyzed for oxidant stress using assays for thiobarbituric acid-reactive substances, protein carbonyl, 8-isoprostane, and total antioxidant capacity. For each subject, raw assay data were normalized to individual baseline samples and expressed as fold-change from baseline. Results were compared using a one-sample t test with Bonferroni correction for multiple comparisons. Sixteen patients (ten with TOF and six with VSD) were enrolled in the study, and there were no major postoperative complications observed. For the entire cohort, there was an immediate, rapid increase in myocardial oxidative stress that was sustained for 10 min following aortic cross-clamp removal in all biomarker assays (all P < 0.01), except total antioxidant capacity. Infant cardiac surgery is associated with a rapid, robust, and time-dependent increase in myocardial oxidant stress as measured from the coronary sinus in vivo. Future studies with larger enrollment are necessary to assess any association between myocardial oxidative stress and early postoperative outcomes.

  9. Modern non-invasive mechanical ventilation turns 25.

    PubMed

    Díaz Lobato, Salvador; Mayoralas Alises, Sagrario

    2013-11-01

    The history of non-invasive mechanical ventilation goes back more than 100 years, but it was not until 1987 when what we could call "modern" non-invasive mechanical ventilation was developed. The description of Delaubier and Rideau of a patient with Duchenne's disease who had been effectively ventilated through a nasal mask marked the start of a new era in the history of non-invasive mechanical ventilation. Over these last 25years, we have witnessed exponential growth in its use, field of activity and technological advances on an exciting fast-paced track. We believe that it is time to review the main milestones that have marked the development of non-invasive mechanical ventilation to date, while paying homage to this therapeutic method that has contributed so much to the advancement of respiratory medicine in the last 25years.

  10. Angiographic correlations of patients with small vessel disease diagnosed by adenosine-stress cardiac magnetic resonance imaging.

    PubMed

    Pilz, Guenter; Klos, Markus; Ali, Eman; Hoefling, Berthold; Scheck, Roland; Bernhardt, Peter

    2008-01-31

    Cardiac magnetic resonance imaging (CMR) with adenosine-stress myocardial perfusion is gaining importance for the detection and quantification of coronary artery disease (CAD). However, there is little knowledge about patients with CMR-detected ischemia, but having no relevant stenosis as seen on coronary angiography (CA). The aims of our study were to characterize these patients by CMR and CA and evaluate correlations and potential reasons for the ischemic findings. 73 patients with an indication for CA were first scanned on a 1.5T whole-body CMR-scanner including adenosine-stress first-pass perfusion. The images were analyzed by two independent investigators for myocardial perfusion which was classified as subendocardial ischemia (n = 22), no perfusion deficit (n = 27, control 1), or more than subendocardial ischemia (n = 24, control 2). All patients underwent CA, and a highly significant correlation between the classification of CMR perfusion deficit and the degree of coronary luminal narrowing was found. For quantification of coronary blood flow, corrected Thrombolysis in Myocardial Infarction (TIMI) frame count (TFC) was evaluated for the left anterior descending (LAD), circumflex (LCX) and right coronary artery (RCA). The main result was that corrected TFC in all coronaries was significantly increased in study patients compared to both control 1 and to control 2 patients. Study patients had hypertension or diabetes more often than control 1 patients. In conclusion, patients with CMR detected subendocardial ischemia have prolonged coronary blood flow. In connection with normal resting flow values in CAD, this supports the hypothesis of underlying coronary microvascular impairment. CMR stress perfusion differentiates non-invasively between this entity and relevant CAD.

  11. Photoionization sensors for non-invasive medical diagnostics

    NASA Astrophysics Data System (ADS)

    Mustafaev, Aleksandr; Rastvorova, Iuliia; Khobnya, Kristina; Podenko, Sofia

    2016-09-01

    The analysis of biomarkers can help to identify the significant number of diseases: lung cancer, tuberculosis, diabetes, high levels of stress, psychosomatic disorders etc. To implement continuous monitoring of the state of human health, compact VUV photoionization detector with current-voltage measurement is designed by Saint-Petersburg Mining University Plasma Research Group. This sensor is based on the patented method of stabilization of electric parameters - CES (Collisional Electron Spectroscopy). During the operation at atmospheric pressure VUV photoionization sensor measures the energy of electrons, produced in the ionization with the resonance photons, whose wavelength situated in the vacuum ultraviolet (VUV). A special software was developed to obtain the second-order derivative of the I-U characteristics, taken by the VUV sensor, to construct the energy spectra of the characteristic electrons. VUV photoionization detector has an unique set of parameters: small size (10*10*1 mm), low cost, wide range of recognizable molecules, as well as accuracy, sufficient for using this instrument for the medical purposes. This device can be used for non-invasive medical diagnostics without compromising the quality of life, for control of environment and human life. Work supported by Foundation for Assistance to Small Innovative Enterprises in Science and Technology.

  12. Non-invasive biomarkers of lung inflammation in smoking subjects.

    PubMed

    Malerba, M; Montuschi, P

    2012-01-01

    Cigarette smoking is the most important risk factor for the development of chronic obstructive pulmonary disease (COPD) and lung cancer, but only a part of smoking subjects develop these respiratory pathologies. Therefore, it is necessary to find sensible parameters to detect early lung alterations due to chronic tobacco smoke exposure. Long-term cigarette smoking is associated with a persistent inflammatory response in the lung that leads to tissue injury and dysfunction. Bronchoscopy and bronchial biopsies are the gold standard techniques for assessing pulmonary inflammation, but are invasive and not routinely used. Cellular analysis of induced sputum and measurement of fraction of exhaled nitric oxide (F(E)NO) are validated non-invasive techniques for assessing respiratory inflammation. Measurement of biomolecules in sputum supernatants and exhaled breath condensate (EBC) are used as a research tool, but require standardization of procedures and, generally, analytical validation. Electronic nose differentiates healthy smokers from healthy nonsmokers based on breath volatile organic compounds (VOC) patterns. These techniques are potentially useful for identifying biomarkers of pulmonary inflammation and oxidative stress. Induced sputum, F(E)NO, EBC and electronic nose are suitable for longitudinal sampling, thereby facilitating monitoring of lung damage process. This approach could enable an early identification of subgroups of healthy smokers at higher risk for tobacco-induced lung damage and prompt planning of secondary prevention strategies.

  13. Non-Invasive Respiratory Impedance Enhances Cerebral Perfusion in Healthy Adults

    PubMed Central

    Favilla, Christopher G.; Parthasarathy, Ashwin B.; Detre, John A.; Yodh, Arjun G.; Mullen, Michael T.; Kasner, Scott E.; Gannon, Kimberly; Messé, Steven R.

    2017-01-01

    Optimization of cerebral blood flow (CBF) is the cornerstone of clinical management in a number of neurologic diseases, most notably ischemic stroke. Intrathoracic pressure influences cardiac output and has the potential to impact CBF. Here, we aim to quantify cerebral hemodynamic changes in response to increased respiratory impedance (RI) using a non-invasive respiratory device. We measured cerebral perfusion under varying levels of RI (6 cm H2O, 9 cm H2O, and 12 cm H2O) in 20 healthy volunteers. Simultaneous measurements of microvascular CBF and middle cerebral artery mean flow velocity (MFV), respectively, were performed with optical diffuse correlation spectroscopy and transcranial Doppler ultrasound. At a high level of RI, MFV increased by 6.4% compared to baseline (p = 0.004), but changes in cortical CBF were non-significant. In a multivariable linear regression model accounting for end-tidal CO2, RI was associated with increases in both MFV (coefficient: 0.49, p < 0.001) and cortical CBF (coefficient: 0.13, p < 0.001), although the magnitude of the effect was small. Manipulating intrathoracic pressure via non-invasive RI was well tolerated and produced a small but measurable increase in cerebral perfusion in healthy individuals. Future studies in acute ischemic stroke patients with impaired cerebral autoregulation are warranted in order to assess whether RI is feasible as a novel non-invasive therapy for stroke. PMID:28261153

  14. Non-invasive hemodynamic assessment of aortic coarctation: validation with in vivo measurements.

    PubMed

    Itu, Lucian; Sharma, Puneet; Ralovich, Kristóf; Mihalef, Viorel; Ionasec, Razvan; Everett, Allen; Ringel, Richard; Kamen, Ali; Comaniciu, Dorin

    2013-04-01

    We propose a CFD-based approach for the non-invasive hemodynamic assessment of pre- and post-operative coarctation of aorta (CoA) patients. Under our approach, the pressure gradient across the coarctation is determined from computational modeling based on physiological principles, medical imaging data, and routine non-invasive clinical measurements. The main constituents of our approach are a reduced-order model for computing blood flow in patient-specific aortic geometries, a parameter estimation procedure for determining patient-specific boundary conditions and vessel wall parameters from non-invasive measurements, and a comprehensive pressure-drop formulation coupled with the overall reduced-order model. The proposed CFD-based algorithm is fully automatic, requiring no iterative tuning procedures for matching the computed results to observed patient data, and requires approximately 6-8 min of computation time on a standard personal computer (Intel Core2 Duo CPU, 3.06 GHz), thus making it feasible for use in a clinical setting. The initial validation studies for the pressure-drop computations have been performed on four patient datasets with native or recurrent coarctation, by comparing the results with the invasively measured peak pressure gradients recorded during routine cardiac catheterization procedure. The preliminary results are promising, with a mean absolute error of less than 2 mmHg in all the patients.

  15. Non-invasive electrocardiogram detection of in vivo zebrafish embryos using electric potential sensors

    NASA Astrophysics Data System (ADS)

    Rendon-Morales, E.; Prance, R. J.; Prance, H.; Aviles-Espinosa, R.

    2015-11-01

    In this letter, we report the continuous detection of the cardiac electrical activity in embryonic zebrafish using a non-invasive approach. We present a portable and cost-effective platform based on the electric potential sensing technology, to monitor in vivo electrocardiogram activity from the zebrafish heart. This proof of principle demonstration shows how electrocardiogram measurements from the embryonic zebrafish may become accessible by using electric field detection. We present preliminary results using the prototype, which enables the acquisition of electrophysiological signals from in vivo 3 and 5 days-post-fertilization zebrafish embryos. The recorded waveforms show electrocardiogram traces including detailed features such as QRS complex, P and T waves.

  16. Heart rate complexity: A novel approach to assessing cardiac stress reactivity.

    PubMed

    Brindle, Ryan C; Ginty, Annie T; Phillips, Anna C; Fisher, James P; McIntyre, David; Carroll, Douglas

    2016-04-01

    Correlation dimension (D2), a measure of heart rate (HR) complexity, has been shown to decrease in response to acute mental stress and relate to adverse cardiovascular health. However, the relationship between stress-induced changes in D2 and HR has yet to be established. The present studies aimed to assess this relationship systematically while controlling for changes in respiration and autonomic activity. In Study 1 (N = 25) D2 decreased during stress and predicted HR reactivity even after adjusting for changes in respiration rate, and cardiac vagal tone. This result was replicated in Study 2 (N = 162) and extended by including a measure of cardiac sympathetic activity; correlation dimension remained an independent predictor of HR reactivity in a hierarchical linear model containing measures of cardiac parasympathetic and sympathetic activity and their interaction. These results suggest that correlation dimension may provide additional information regarding cardiac stress reactivity above that provided by traditional measures of cardiac autonomic function.

  17. Non-invasive determination of the complete elastic moduli of spider silks

    NASA Astrophysics Data System (ADS)

    Koski, Kristie J.; Akhenblit, Paul; McKiernan, Keri; Yarger, Jeffery L.

    2013-03-01

    Spider silks possess nature’s most exceptional mechanical properties, with unrivalled extensibility and high tensile strength. Unfortunately, our understanding of silks is limited because the complete elastic response has never been measured—leaving a stark lack of essential fundamental information. Using non-invasive, non-destructive Brillouin light scattering, we obtain the entire stiffness tensors (revealing negative Poisson’s ratios), refractive indices, and longitudinal and transverse sound velocities for major and minor ampullate spider silks: Argiope aurantia, Latrodectus hesperus, Nephila clavipes, Peucetia viridans. These results completely quantify the linear elastic response for all possible deformation modes, information unobtainable with traditional stress-strain tests. For completeness, we apply the principles of Brillouin imaging to spatially map the elastic stiffnesses on a spider web without deforming or disrupting the web in a non-invasive, non-contact measurement, finding variation among discrete fibres, junctions and glue spots. Finally, we provide the stiffness changes that occur with supercontraction.

  18. Non-invasive microfluidic gap junction assay.

    PubMed

    Chen, Sisi; Lee, Luke P

    2010-03-01

    Gap junctions are protein channels between cells that allow direct electrical and metabolic coupling via the exchange of biomolecules and ions. Their expression, though ubiquitous in most mammalian cell types, is especially important for the proper functioning of cardiac and neuronal systems. Many existing methods for studying gap junction communication suffer from either unquantifiable data or difficulty of use. Here, we measure the extent of dye spread and effective diffusivities through gap junction connected cells using a quantitative microfluidic cell biology platform. After loading dye by hydrodynamic focusing of calcein/AM, dye transfer dynamics into neighboring, unexposed cells can be monitored via timelapse fluorescent microscopy. By using a selective microfluidic dye loading over a confluent layer of cells, we found that high expression of gap junctions in C6 cells transmits calcein across the monolayer with an effective diffusivity of 3.4 x 10(-13) m(2)/s, which are highly coupled by Cx43. We also found that the gap junction blocker 18alpha-GA works poorly in the presence of serum even at high concentrations (50 microM); however, it is highly effective down to 2.5 microM in the absence of serum. Furthermore, when the drug is washed out, dye spread resumes rapidly within 1 min for all doses, indicating the drug does not affect transcriptional regulation of connexins in these Cx43+ cells, in contrast to previous studies. This integrated microfluidic platform enables the in situ monitoring of gap junction communication, yielding dynamic information about intercellular molecular transfer and pharmacological inhibition and recovery.

  19. Non-invasive femoropopliteal assessment: is that angiogram really necessary?

    PubMed Central

    Shearman, C P; Gwynn, B R; Curran, F; Gannon, M X; Simms, M H

    1986-01-01

    A method of non-invasive preoperative assessment of chronically ischaemic legs was developed that used clinical data and data derived from Doppler ultrasonography to produce a numerical score that could be compared with an angiographic score for stenosis of the popliteal artery trifurcation. The two scoring systems were applied retrospectively to 144 legs after femorodistal bypass. A close correlation was observed (r = 0.89, p less than 0.001), and both systems tended to predict the level of grafting undertaken. A prospective comparison was then made in 81 ischaemic legs that were examined by arteriography; the correlation between the two scoring systems remained close (r = 0.89, p less than 0.001), and the level of bypass was correctly predicted by the non-invasive assessment in 44 of 50 legs that were operated on. Use of the non-invasive assessment subsequently greatly reduced the indications for preoperative arteriography in patients requiring femorodistal vascular reconstruction. PMID:3094784

  20. Asymmetric sympathetic output: The dorsomedial hypothalamus as a potential link between emotional stress and cardiac arrhythmias.

    PubMed

    Fontes, Marco Antônio Peliky; Filho, Marcelo Limborço; Santos Machado, Natália L; de Paula, Cristiane Amorim; Souza Cordeiro, Letícia M; Xavier, Carlos Henrique; Marins, Fernanda Ribeiro; Henderson, Luke; Macefield, Vaughan G

    2017-01-17

    The autonomic response to emotional stress, while involving several target organs, includes an important increase in sympathetic drive to the heart. There is ample evidence that cardiac sympathetic innervation is lateralized, and asymmetric autonomic output to the heart during stress is postulated to be a causal factor that precipitates cardiac arrhythmias. Recent animal studies provided a new picture of the central pathways involved in the cardiac sympathetic response evoked by emotional stress, pointing out a key role for the region of dorsomedial hypothalamus. However, how much of this information can be extrapolated to humans? Analysis of human functional imaging data at rest or during emotional stress shows some consistency with the components that integrate these pathways, and attention must be given to the asymmetric activation of subcortical sites. In this short review, we will discuss related findings in humans and animals, aiming to understand the neurogenic background for the origin of emotional stress-induced cardiac arrhythmias.

  1. Non-invasive high resolving power quantum microscope

    NASA Astrophysics Data System (ADS)

    Karmakar, Sanjit; Meyers, Ronald; Shih, Yanhua

    2013-09-01

    The development of a non-invasive high resolving power quantum microscope would further advance progress in research and development in biomedical and biosciences as well as the field of medical technology. Longer wavelengths, i.e visible or near-infrared, provide less invasive impact. On the other hand shorter wavelengths, i.e. UV, can provide better resolving power. That is why the development of a non-invasive high resolving power quantum microscope is critical. In this article, we propose such a microscope by using two-color entangled photon ghost imaging technology.

  2. An Acetone Nanosensor For Non-invasive Diabetes Detection

    NASA Astrophysics Data System (ADS)

    Wang, L.; Yun, X.; Stanacevic, M.; Gouma, P. I.

    2009-05-01

    Diabetes is a most common disease worldwide. Acetone in exhaled breath is a known biomarker of Type- 1 diabetes. An exhaled breath analyzer has been developed with the potential to diagnose diabetes as a non-invasive alternative of the currently used blood-based diagnostics. This device utilizes a chemiresistor based on ferroelectric tungsten oxide nanoparticles and detects acetone selectively in breath-simulated media. Real-time monitoring of the acetone concentration is feasible, potentially making this detector a revolutionary, non- invasive, diabetes diagnostic tool.

  3. Non-invasive brain stimulation in early rehabilitation after stroke.

    PubMed

    Blesneag, A V; Popa, L; Stan, A D

    2015-01-01

    The new tendency in rehabilitation involves non-invasive tools that, if applied early after stroke, promote neurorecovery. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may correct the disruption of cortical excitability and effectively contribute to the restoration of movement and speech. The present paper analyses the results of non-invasive brain stimulation (NIBS) trials, highlighting different aspects related to the repetitive transcranial magnetic stimulation frequency, transcranial direct current stimulation polarity, the period and stimulation places in acute and subacute ischemic strokes. The risk of adverse events, the association with motor or language recovery specific training, and the cumulative positive effect evaluation are also discussed.

  4. Non-invasive computer-assisted measurement of knee alignment.

    PubMed

    Clarke, Jon V; Riches, Philip E; Picard, Frederic; Deakin, Angela H

    2012-01-01

    The quantification of knee alignment is a routine part of orthopaedic practice and is important for monitoring disease progression, planning interventional strategies, and follow-up of patients. Currently available technologies such as radiographic measurements have a number of drawbacks. The aim of this study was to validate a potentially improved technique for measuring knee alignment under different conditions. An image-free navigation system was adapted for non-invasive use through the development of external infrared tracker mountings. Stability was assessed by comparing the variance (F-test) of repeated mechanical femoro-tibial (MFT) angle measurements for a volunteer and a leg model. MFT angles were then measured supine, standing and with varus-valgus stress in asymptomatic volunteers who each underwent two separate registrations and repeated measurements for each condition. The mean difference and 95% limits of agreement were used to assess intra-registration and inter-registration repeatability. For multiple registrations the range of measurements for the external mountings was 1° larger than for the rigid model with statistically similar variance (p=0.34). Thirty volunteers were assessed (19 males, 11 females) with a mean age of 41 years (range: 20-65) and a mean BMI of 26 (range: 19-34). For intra-registration repeatability, consecutive coronal alignment readings agreed to almost ±1°, with up to ±0.5° loss of repeatability for coronal alignment measured before and after stress maneuvers, and a ±0.2° loss following stance trials. Sagittal alignment measurements were less repeatable overall by an approximate factor of two. Inter-registration agreement limits for coronal and sagittal supine MFT angles were ±1.6° and ±2.3°, respectively. Varus and valgus stress measurements agreed to within ±1.3° and ±1.1°, respectively. Agreement limits for standing MFT angles were ±2.9° (coronal) and ±5.0° (sagittal), which may have reflected a variation

  5. Non-invasive assessment of adrenocortical function in captive Nile crocodiles (Crocodylus niloticus).

    PubMed

    Ganswindt, Stefanie B; Myburgh, Jan G; Cameron, Elissa Z; Ganswindt, Andre

    2014-11-01

    The occurrence of stress-inducing factors in captive crocodilians is a concern, since chronic stress can negatively affect animal health and reproduction, and hence production. Monitoring stress in wild crocodiles could also be beneficial for assessing the state of health in populations which are potentially threatened by environmental pollution. In both cases, a non-invasive approach to assess adrenocortical function as a measure of stress would be preferable, as animals are not disturbed during sample collection, and therefore sampling is feedback-free. So far, however, such a non-invasive method has not been established for any crocodilian species. As an initial step, we therefore examined the suitability of two enzyme-immunoassays, detecting faecal glucocorticoid metabolites (FGMs) with a 11β,21-diol-20-one and 5β-3α-ol-11-one structure, respectively, for monitoring stress-related physiological responses in captive Nile crocodiles (Crocodylus niloticus). An adrenocorticotropic hormone (ACTH) challenge was performed on 10 sub-adult crocodiles, resulting in an overall increase in serum corticosterone levels of 272% above the pre-injection levels 5h post-injection. Saline-treated control animals (n=8) showed an overall increase of 156% in serum corticosterone levels 5h post-administration. Faecal samples pre- and post-injection could be obtained from three of the six individually housed crocodiles, resulting in FGM concentrations 136-380% above pre-injection levels, always detected in the first sample collected post-treatment (7-15 days post-injection). FGM concentrations seem comparatively stable at ambient temperatures for up to 72 h post-defaecation. In conclusion, non-invasive hormone monitoring can be used for assessing adrenocortical function in captive Nile crocodiles based on FGM analysis.

  6. Non-invasive, energy-based assessment of patient-specific material properties of arterial tissue.

    PubMed

    Smoljkić, M; Vander Sloten, J; Segers, P; Famaey, N

    2015-10-01

    The mechanical properties of human biological tissue vary greatly. The determination of arterial material properties should be based on experimental data, i.e. diameter, length, intramural pressure, axial force and stress-free geometry. Currently, clinical data provide only non-invasively measured pressure-diameter data for superficial arteries (e.g. common carotid and femoral artery). The lack of information forces us to take into account certain assumptions regarding the in situ configuration to estimate material properties in vivo. This paper proposes a new, non-invasive, energy-based approach for arterial material property estimation. This approach is compared with an approach proposed in the literature. For this purpose, a simplified finite element model of an artery was used as a mock experimental situation. This method enables exact knowledge of the actual material properties, thereby allowing a quantitative evaluation of material property estimation approaches. The results show that imposing conditions on strain energy can provide a good estimation of the material properties from the non-invasively measured pressure and diameter data.

  7. The influence of motor activity on the development of cardiac arrhythmias during experimental emotional stress

    NASA Technical Reports Server (NTRS)

    Ulyaninskiy, L. S.; Urmancheyeva, T. G.; Stepanyan, Y. P.; Fufacheva, A. A.; Gritsak, A. V.; Kuznetsova, B. A.; Kvitka, A. A.

    1982-01-01

    Experimental emotional stress which can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular, extrasystoles and paroxysmal ventricular tachysystoles was studied. In these conditions the adrenalin content in the blood and myocardium is increased 3 to 4 times. It is found that moderate motor activity leads to a relative decrease of adrenalin in the myocardium and arrest of cardiac arrhythmias.

  8. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, Richard M.; Packer, Samuel

    1984-01-01

    There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

  9. Non-invasive method of measuring cerebral spinal fluid pressure

    NASA Technical Reports Server (NTRS)

    Borchert, Mark S. (Inventor); Lambert, James L. (Inventor)

    2000-01-01

    The invention provides a method of non-invasively determining intracranial pressure from measurements of an eye. A parameter of an optic nerve of the eye is determined, along with an intraocular pressure of the eye. The intracranial pressure may be determined from the intraocular pressure and the parameter.

  10. Eyeblink Conditioning: A Non-Invasive Biomarker for Neurodevelopmental Disorders

    ERIC Educational Resources Information Center

    Reeb-Sutherland, Bethany C.; Fox, Nathan A.

    2015-01-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition,…

  11. Non-invasive treatment options for focal cortical dysplasia

    PubMed Central

    WANG, TING-TING; ZHOU, DONG

    2016-01-01

    Focal cortical dysplasia (FCD) presents a strong clinical challenge especially for the treatment of the associated epilepsy. Epilepsy in FCD is often treatment-resistant and constitutes 50% of treatment-resistant cases. Antiepileptic drugs (AEDs) have been widely used in the treatment of FCD. However, evidence to suggest their specific effect on the treatment of FCD remains to be established. In view of this resistance, several alternative treatments have been suggested. Although treatment currently involves surgical management, non-invasive treatments have been identified. The aim of the present review, was to assess non-invasive management strategies including, i) mammalian target of rapamycin (mTOR) inhibitors, ii) ketogenic diet (KD), and iii) vagus nerve stimulation (VNS). In addition, we discussed the literature available regarding the use of AEDs in FCD. Experiments conducted with mammals detailing rapamycin gene mutations in FCD have produced vital information for exploring treatment options using mTOR inhibitors. Of note is the importance of KD in children with FCD. This diet has been shown to modify disease progression by attenuating chromatin modification, a master regulator for gene expression and functional adaptation of the cell. FCD has also been studied widely with neurostimulation techniques. The outcomes of these techniques have been found to be variable. For widespread dysplasias, VNS has been shown to produce responder rates of >50%. Nevertheless, non-invasive cranial nerve stimulation techniques such as transcutaneous VNS and non-invasive VNS are gaining better patient compatibility, albeit their efficacy remains to be established. PMID:27168769

  12. Method for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, R.M.; Packer, S.

    1984-10-30

    An apparatus and method is disclosed for diagnosing ocular cancer that is both non-invasive and accurate. The apparatus comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67. 2 figs.

  13. Non-invasive in vivo measurement of macular carotenoids

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2009-01-01

    A non-invasive in vivo method for assessing macular carotenoids includes performing Optical Coherence Tomography (OCT) on a retina of a subject. A spatial representation of carotenoid levels in the macula based on data from the OCT of the retina can be generated.

  14. A kinase interacting protein (AKIP1) is a key regulator of cardiac stress

    PubMed Central

    Sastri, Mira; Haushalter, Kristofer J.; Panneerselvam, Mathivadhani; Chang, Philip; Fridolfsson, Heidi; Finley, J. Cameron; Ng, Daniel; Schilling, Jan M.; Miyanohara, Atsushi; Day, Michele E.; Hakozaki, Hiro; Petrosyan, Susanna; Koller, Antonius; King, Charles C.; Darshi, Manjula; Blumenthal, Donald K.; Ali, Sameh Saad; Roth, David M.; Patel, Hemal H.; Taylor, Susan S.

    2013-01-01

    cAMP-dependent protein kinase (PKA) regulates a myriad of functions in the heart, including cardiac contractility, myocardial metabolism, and gene expression. However, a molecular integrator of the PKA response in the heart is unknown. Here, we show that the PKA adaptor A-kinase interacting protein 1 (AKIP1) is up-regulated in cardiac myocytes in response to oxidant stress. Mice with cardiac gene transfer of AKIP1 have enhanced protection to ischemic stress. We hypothesized that this adaptation to stress was mitochondrial-dependent. AKIP1 interacted with the mitochondrial localized apoptosis inducing factor (AIF) under both normal and oxidant stress. When cardiac myocytes or whole hearts are exposed to oxidant and ischemic stress, levels of both AKIP1 and AIF were enhanced. AKIP1 is preferentially localized to interfibrillary mitochondria and up-regulated in this cardiac mitochondrial subpopulation on ischemic injury. Mitochondria isolated from AKIP1 gene-transferred hearts showed increased mitochondrial localization of AKIP1, decreased reactive oxygen species generation, enhanced calcium tolerance, decreased mitochondrial cytochrome C release, and enhance phosphorylation of mitochondrial PKA substrates on ischemic stress. These observations highlight AKIP1 as a critical molecular regulator and a therapeutic control point for stress adaptation in the heart. PMID:23319652

  15. Non-invasive mouthguard biosensor for continuous salivary monitoring of metabolites.

    PubMed

    Kim, Jayoung; Valdés-Ramírez, Gabriela; Bandodkar, Amay J; Jia, Wenzhao; Martinez, Alexandra G; Ramírez, Julian; Mercier, Patrick; Wang, Joseph

    2014-04-07

    The present work describes the first example of a wearable salivary metabolite biosensor based on the integration of a printable enzymatic electrode on a mouthguard. The new mouthguard enzymatic biosensor, based on an immobilized lactate oxidase and a low potential detection of the peroxide product, exhibits high sensitivity, selectivity and stability using whole human saliva samples. Such non-invasive mouthguard metabolite biosensors could tender useful real-time information regarding a wearer's health, performance and stress level, and thus hold considerable promise for diverse biomedical and fitness applications.

  16. Limitations of Stroke Volume Estimation by Non-Invasive Blood Pressure Monitoring in Hypergravity

    PubMed Central

    2015-01-01

    Background Altitude and gravity changes during aeromedical evacuations induce exacerbated cardiovascular responses in unstable patients. Non-invasive cardiac output monitoring is difficult to perform in this environment with limited access to the patient. We evaluated the feasibility and accuracy of stroke volume estimation by finger photoplethysmography (SVp) in hypergravity. Methods Finger arterial blood pressure (ABP) waveforms were recorded continuously in ten healthy subjects before, during and after exposure to +Gz accelerations in a human centrifuge. The protocol consisted of a 2-min and 8-min exposure up to +4 Gz. SVp was computed from ABP using Liljestrand, systolic area, and Windkessel algorithms, and compared with reference values measured by echocardiography (SVe) before and after the centrifuge runs. Results The ABP signal could be used in 83.3% of cases. After calibration with echocardiography, SVp changes did not differ from SVe and values were linearly correlated (p<0.001). The three algorithms gave comparable SVp. Reproducibility between SVp and SVe was the best with the systolic area algorithm (limits of agreement −20.5 and +38.3 ml). Conclusions Non-invasive ABP photoplethysmographic monitoring is an interesting technique to estimate relative stroke volume changes in moderate and sustained hypergravity. This method may aid physicians for aeronautic patient monitoring. PMID:25798613

  17. Long term non-invasive domiciliary assisted ventilation for respiratory failure following thoracoplasty.

    PubMed Central

    Jackson, M.; Smith, I.; King, M.; Shneerson, J.

    1994-01-01

    BACKGROUND--Ventilatory failure is a well recognised complication of patients who have had a thoracoplasty for tuberculosis, but there are few data regarding the value of long term non-invasive assisted ventilation in this situation. METHODS--Thirty two patients who had had a thoracoplasty 20-46 years previously and who had developed respiratory failure were treated with nocturnal cuirass assisted ventilation or nasal positive pressure ventilation. Their survival and changes in arterial blood gases, nocturnal oximetry, and pulmonary function tests were assessed. RESULTS--The actuarial survival rates at one, three, five, and seven years after starting treatment were 91%, 74%, 64%, and 55%, respectively. Only seven of the 13 deaths were directly attributable to chronic respiratory or cardiac failure. The arterial PO2, PCO2, mean nocturnal oxygen saturation, vital capacity, and maximal inspiratory and expiratory pressures had all improved at the time of the initial post-treatment assessment (mean 12 days after starting treatment), but no subsequent improvements were seen after up to 48 months of follow up. Neither survival nor physiological improvements were correlated with the patients' age, the interval since thoracoplasty, or the pretreatment arterial blood gas tensions or results of pulmonary function tests. CONCLUSIONS--These results show that, even when ventilatory failure has developed, the prognosis with non-invasive assisted ventilation is good and the physiological abnormalities can be partially reversed. Patients who develop respiratory failure after a thoracoplasty should be considered for this type of long term domiciliary treatment. PMID:7940434

  18. Monitoring high-risk patients: minimally invasive and non-invasive possibilities.

    PubMed

    Renner, Jochen; Grünewald, Matthias; Bein, Berthold

    2016-06-01

    Over the past decades, there has been considerable progress in the field of less invasive haemodynamic monitoring technologies. Substantial evidence has accumulated, which supports the continuous measurement and optimization of flow-based variables such as stroke volume, that is, cardiac output, in order to prevent occult hypoperfusion and consequently to improve patients' outcome in the perioperative setting. However, there is a striking gap between the developments in haemodynamic monitoring and the increasing evidence to implement defined treatment protocols based on the measured variables, and daily clinical routine. Recent trials have shown that perioperative morbidity and mortality is higher than anticipated. This emphasizes the need for the anaesthesia community to address this issue and promotes the implementation of proven concepts into clinical practice in order to improve patients' outcome, especially in high-risk patients. The advances in minimally invasive and non-invasive monitoring techniques can be seen as a driving force in this respect, as the degree of invasiveness of any monitoring tool determines the frequency of its application, especially in the operating room (OR). From this point of view, we are very confident that some of these minimally invasive and non-invasive haemodynamic monitoring technologies will become an inherent part of our monitoring armamentarium in the OR and in the intensive care unit (ICU).

  19. Non-Invasive Ventilation in Patients with Heart Failure: A Systematic Review and Meta-Analysis

    PubMed Central

    Bittencourt, Hugo Souza; dos Reis, Helena França Correia; Lima, Melissa Santos; Gomes Neto, Mansueto

    2017-01-01

    Non-invasive ventilation (NIV) may perfect respiratory and cardiac performance in patients with heart failure (HF). The objective of the study to establish, through systematic review and meta-analysis, NIV influence on functional capacity of HF patients. A systematic review with meta-analysis of randomized studies was carried out through research of databases of Cochrane Library, SciELO, Pubmed and PEDro, using the key-words: heart failure, non-invasive ventilation, exercise tolerance; and the free terms: bi-level positive airway pressure (BIPAP), continuous positive airway pressure (CPAP), and functional capacity (terms were searched for in English and Portuguese) using the Boolean operators AND and OR. Methodological quality was ensured through PEDro scale. Weighted averages and a 95% confidence interval (CI) were calculated. The meta-analysis was done thorugh the software Review Manager, version 5.3 (Cochrane Collaboration). Four randomized clinical trials were included. Individual studies suggest NIV improved functional capacity. NIV resulted in improvement in the distance of the six-minute walk test (6MWT) (68.7m 95%CI: 52.6 to 84.9) in comparison to the control group. We conclude that the NIV is an intervention that promotes important effects in the improvement of functional capacity of HF patients. However, there is a gap in literature on which are the most adequate parameters for the application of this technique. PMID:28099587

  20. Complexity of cardiac signals for predicting changes in alpha-waves after stress in patients undergoing cardiac catheterization

    NASA Astrophysics Data System (ADS)

    Chiu, Hung-Chih; Lin, Yen-Hung; Lo, Men-Tzung; Tang, Sung-Chun; Wang, Tzung-Dau; Lu, Hung-Chun; Ho, Yi-Lwun; Ma, Hsi-Pin; Peng, Chung-Kang

    2015-08-01

    The hierarchical interaction between electrical signals of the brain and heart is not fully understood. We hypothesized that the complexity of cardiac electrical activity can be used to predict changes in encephalic electricity after stress. Most methods for analyzing the interaction between the heart rate variability (HRV) and electroencephalography (EEG) require a computation-intensive mathematical model. To overcome these limitations and increase the predictive accuracy of human relaxing states, we developed a method to test our hypothesis. In addition to routine linear analysis, multiscale entropy and detrended fluctuation analysis of the HRV were used to quantify nonstationary and nonlinear dynamic changes in the heart rate time series. Short-time Fourier transform was applied to quantify the power of EEG. The clinical, HRV, and EEG parameters of postcatheterization EEG alpha waves were analyzed using change-score analysis and generalized additive models. In conclusion, the complexity of cardiac electrical signals can be used to predict EEG changes after stress.

  1. Complexity of cardiac signals for predicting changes in alpha-waves after stress in patients undergoing cardiac catheterization.

    PubMed

    Chiu, Hung-Chih; Lin, Yen-Hung; Lo, Men-Tzung; Tang, Sung-Chun; Wang, Tzung-Dau; Lu, Hung-Chun; Ho, Yi-Lwun; Ma, Hsi-Pin; Peng, Chung-Kang

    2015-08-19

    The hierarchical interaction between electrical signals of the brain and heart is not fully understood. We hypothesized that the complexity of cardiac electrical activity can be used to predict changes in encephalic electricity after stress. Most methods for analyzing the interaction between the heart rate variability (HRV) and electroencephalography (EEG) require a computation-intensive mathematical model. To overcome these limitations and increase the predictive accuracy of human relaxing states, we developed a method to test our hypothesis. In addition to routine linear analysis, multiscale entropy and detrended fluctuation analysis of the HRV were used to quantify nonstationary and nonlinear dynamic changes in the heart rate time series. Short-time Fourier transform was applied to quantify the power of EEG. The clinical, HRV, and EEG parameters of postcatheterization EEG alpha waves were analyzed using change-score analysis and generalized additive models. In conclusion, the complexity of cardiac electrical signals can be used to predict EEG changes after stress.

  2. Complexity of cardiac signals for predicting changes in alpha-waves after stress in patients undergoing cardiac catheterization

    PubMed Central

    Chiu, Hung-Chih; Lin, Yen-Hung; Lo, Men-Tzung; Tang, Sung-Chun; Wang, Tzung-Dau; Lu, Hung-Chun; Ho, Yi-Lwun; Ma, Hsi-Pin; Peng, Chung-Kang

    2015-01-01

    The hierarchical interaction between electrical signals of the brain and heart is not fully understood. We hypothesized that the complexity of cardiac electrical activity can be used to predict changes in encephalic electricity after stress. Most methods for analyzing the interaction between the heart rate variability (HRV) and electroencephalography (EEG) require a computation-intensive mathematical model. To overcome these limitations and increase the predictive accuracy of human relaxing states, we developed a method to test our hypothesis. In addition to routine linear analysis, multiscale entropy and detrended fluctuation analysis of the HRV were used to quantify nonstationary and nonlinear dynamic changes in the heart rate time series. Short-time Fourier transform was applied to quantify the power of EEG. The clinical, HRV, and EEG parameters of postcatheterization EEG alpha waves were analyzed using change-score analysis and generalized additive models. In conclusion, the complexity of cardiac electrical signals can be used to predict EEG changes after stress. PMID:26286628

  3. Epac1-dependent phospholamban phosphorylation mediates the cardiac response to stresses

    PubMed Central

    Okumura, Satoshi; Fujita, Takayuki; Cai, Wenqian; Jin, Meihua; Namekata, Iyuki; Mototani, Yasumasa; Jin, Huiling; Ohnuki, Yoshiki; Tsuneoka, Yayoi; Kurotani, Reiko; Suita, Kenji; Kawakami, Yuko; Hamaguchi, Shogo; Abe, Takaya; Kiyonari, Hiroshi; Tsunematsu, Takashi; Bai, Yunzhe; Suzuki, Sayaka; Hidaka, Yuko; Umemura, Masanari; Ichikawa, Yasuhiro; Yokoyama, Utako; Sato, Motohiko; Ishikawa, Fumio; Izumi-Nakaseko, Hiroko; Adachi-Akahane, Satomi; Tanaka, Hikaru; Ishikawa, Yoshihiro

    2014-01-01

    PKA phosphorylates multiple molecules involved in calcium (Ca2+) handling in cardiac myocytes and is considered to be the predominant regulator of β-adrenergic receptor–mediated enhancement of cardiac contractility; however, recent identification of exchange protein activated by cAMP (EPAC), which is independently activated by cAMP, has challenged this paradigm. Mice lacking Epac1 (Epac1 KO) exhibited decreased cardiac contractility with reduced phospholamban (PLN) phosphorylation at serine-16, the major PKA-mediated phosphorylation site. In Epac1 KO mice, intracellular Ca2+ storage and the magnitude of Ca2+ movement were decreased; however, PKA expression remained unchanged, and activation of PKA with isoproterenol improved cardiac contractility. In contrast, direct activation of EPAC in cardiomyocytes led to increased PLN phosphorylation at serine-16, which was dependent on PLC and PKCε. Importantly, Epac1 deletion protected the heart from various stresses, while Epac2 deletion was not protective. Compared with WT mice, aortic banding induced a similar degree of cardiac hypertrophy in Epac1 KO; however, lack of Epac1 prevented subsequent cardiac dysfunction as a result of decreased cardiac myocyte apoptosis and fibrosis. Similarly, Epac1 KO animals showed resistance to isoproterenol- and aging-induced cardiomyopathy and attenuation of arrhythmogenic activity. These data support Epac1 as an important regulator of PKA-independent PLN phosphorylation and indicate that Epac1 regulates cardiac responsiveness to various stresses. PMID:24892712

  4. Non-invasive microsensors for studying cell/tissue physiology

    NASA Astrophysics Data System (ADS)

    Vanegas, D. C.; Taguchi, M.; Chaturvedi, P.; Burrs, S.; McLamore, E. S.

    2013-05-01

    Non-invasive tools that allow real-time quantification of molecules relevant to metabolism, homeostasis, and cell signaling in cells and tissue are of great importance for studying physiology. Several microsensor technologies have been developed to monitor concentration of molecules such as ions, oxygen, electroactive molecules (e.g., nitric oxide, hydrogen peroxide), and biomolecules (e.g., sugars, hormones). The major challenges for microsensors are overcoming relatively low sensitivity and low signal-to-noise ratio. Modern approaches for enhancing microsensor performance focus on the incorporation of catalytic nanomaterials to increase sensitivity, reduce response time, and increase operating range. To improve signal-to-noise ratio, a non-invasive microsensor modality called self-referencing (SR) is being applied. The SR technique allows measurement of temporal and spatial transport dynamics at the cell, tissue, organ, and organismal level.

  5. Non-invasive Imaging of Colitis using Multispectral Optoacoustic Tomography.

    PubMed

    Bhutiani, Neal; Grizzle, William E; Galandiuk, Susan; Otali, Denis; Dryden, Gerald W; Egilmez, Nejat K; McNally, Lacey R

    2016-12-01

    Currently, several non-invasive modalities, including MRI and PET, are being investigated to identify early intestinal inflammation, longitudinally monitor disease status, or detect dysplastic changes in patients with inflammatory bowel disease (IBD). Here, we assess the applicability and utility of multispectral optoacoustic tomography (MSOT) in evaluating the presence and severity of colitis. Mice with bacterial colitis demonstrated a temporally associated increase in mesenteric and colonic vascularity with an increase in mean signal intensity of oxygenated hemoglobin (p=0.004) by MSOT two days after inoculation. These findings were significantly more prominent 7 days after inoculation, with increased mean signal intensity of oxygenated hemoglobin (p=0.0002) and the development of punctate vascular lesions on the colonic surface, which corresponded to changes observed on colonoscopy as well as histology. With improvements in depth of tissue penetration, MSOT may hold potential as a sensitive, accurate, non-invasive imaging tool in evaluation of patients with IBD.

  6. Non-invasive assessments of adipose tissue metabolism in vitro

    PubMed Central

    Abbott, Rosalyn D.; Borowsky, Francis E.; Quinn, Kyle P.; Bernstein, David L.; Georgakoudi, Irene; Kaplan, David L.

    2015-01-01

    Adipose tissue engineering is a diverse area of research where the developed tissues can be used to study normal adipose tissue functions, create disease models in vitro, and replace soft tissue defects in vivo. Increasing attention has been focused on the highly specialized metabolic pathways that regulate energy storage and release in adipose tissues which affect local and systemic outcomes. Non-invasive, dynamic measurement systems are useful to track these metabolic pathways in the same tissue model over time to evaluate long term cell growth, differentiation, and development within tissue engineering constructs. This approach reduces costs and time in comparison to more traditional destructive methods such as biochemical and immunochemistry assays and proteomics assessments. Towards this goal, this review will focus on important metabolic functions of adipose tissues and strategies to evaluate them with noninvasive in vitro methods. Current non-invasive methods, such as measuring key metabolic markers and endogenous contrast imaging will be explored. PMID:26399988

  7. Hepatic steatosis and fibrosis: Non-invasive assessment

    PubMed Central

    Karanjia, Rustam N; Crossey, Mary M E; Cox, I Jane; Fye, Haddy K S; Njie, Ramou; Goldin, Robert D; Taylor-Robinson, Simon D

    2016-01-01

    Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and non-invasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy. PMID:28018096

  8. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    PubMed Central

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm Jr., Martin C.; Austen Jr., William G.; Yarmush, Martin L.

    2015-01-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases. PMID:25965851

  9. Skin rejuvenation with non-invasive pulsed electric fields.

    PubMed

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P; Albadawi, Hassan; Felix Broelsch, G; Watkins, Michael T; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C; Austen, William G; Yarmush, Martin L

    2015-05-12

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  10. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    NASA Astrophysics Data System (ADS)

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C., Jr.; Austen, William G., Jr.; Yarmush, Martin L.

    2015-05-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  11. Non-Invasive Blood Flow Monitoring on the Wrist

    DTIC Science & Technology

    2007-11-02

    INVASIVE BLOOD FLOW MONITORING ON THE WRIST M. Maier, L-G. Lindberg Department of Biomedical Engineering , University of Linköping, Sweden The Swedish...Department of Biomedical Engineering . This study was supported by The Swedish Competence Center of Non-invasive Medical Measurements NIMED...Element Number Author(s) Project Number Task Number Work Unit Number Performing Organization Name(s) and Address(es) Department of Biomedical

  12. SQUID magnetometry applied as non-invasive electroanalytic chemical technique

    SciTech Connect

    Jette, B.D.; MacVicar, M.L.A. )

    1991-03-01

    This paper reports on a SQUID magnetometer, employed as a highly sensitive ammeter, used to perform standard electroanalytic chemical measurements non- invasively. Specifically, the magnetic fields generated by the net ionic movement in the solution of a driven electrochemical system is detected by the gradiometer coils. The SQUID signal can then be compared to conventional current measurements. One such standard measurement investigated is Cyclic Voltametry (CV) which determines the I-V characteristics of an electrochemical system yielding critical kinetic parameters.

  13. Non-invasive assessment of leaf water status using a dual-mode microwave resonator.

    PubMed

    Dadshani, Said; Kurakin, Andriy; Amanov, Shukhrat; Hein, Benedikt; Rongen, Heinz; Cranstone, Steve; Blievernicht, Ulrich; Menzel, Elmar; Léon, Jens; Klein, Norbert; Ballvora, Agim

    2015-01-01

    The water status in plant leaves is a good indicator for the water status in the whole plant revealing stress if the water supply is reduced. The analysis of dynamic aspects of water availability in plant tissues provides useful information for the understanding of the mechanistic basis of drought stress tolerance, which may lead to improved plant breeding and management practices. The determination of the water content in plant tissues during plant development has been a challenge and is currently feasible based on destructive analysis only. We present here the application of a non-invasive quantitative method to determine the volumetric water content of leaves and the ionic conductivity of the leaf juice from non-invasive microwave measurements at two different frequencies by one sensor device. A semi-open microwave cavity loaded with a ceramic dielectric resonator and a metallic lumped-element capacitor- and inductor structure was employed for non-invasive microwave measurements at 150 MHz and 2.4 Gigahertz on potato, maize, canola and wheat leaves. Three leaves detached from each plant were chosen, representing three developmental stages being representative for tissue of various age. Clear correlations between the leaf- induced resonance frequency shifts and changes of the inverse resonator quality factor at 2.4 GHz to the gravimetrically determined drying status of the leaves were found. Moreover, the ionic conductivity of Maize leaves, as determined from the ratio of the inverse quality factor and frequency shift at 150 MHz by use of cavity perturbation theory, was found to be in good agreement with direct measurements on plant juice. In conjunction with a compact battery- powered circuit board- microwave electronic module and a user-friendly software interface, this method enables rapid in-vivo water amount assessment of plants by a handheld device for potential use in the field.

  14. Invasive and non-invasive assessment of portal hypertension.

    PubMed

    Leung, Jonathan Chung-Fai; Loong, Thomson Chi-Wang; Pang, James; Wei, Jeremy Lok; Wong, Vincent Wai-Sun

    2017-03-30

    Portal hypertension is the central driver of complications in patients with chronic liver diseases and cirrhosis. The diagnosis of portal hypertension has important prognostic and clinical implications. In particular, screening for varices in patients with portal hypertension can effectively reduce the morbidity and mortality of variceal bleeding. In this article, we review the invasive and non-invasive methods to assess portal hypertension. Hepatic venous pressure gradient remains the gold standard to measure portal pressure but is invasive and seldom performed outside expert centers and research settings. In recent years, a number of non-invasive tests of fibrosis have shown good correlation with liver histology. They also show promise in identifying patients with portal hypertension and large varices. As a result, the latest Baveno VI consensus guidelines endorse the use of liver stiffness measurement by transient elastography and platelet count as initial assessment to select patients for varices screening. On the other hand, the performance of non-invasive tests in assessing the response to non-selective beta-blockers or transjugular intrahepatic portosystemic shunting is either suboptimal or unclear.

  15. Method for non-invasively recording electrocardiograms in conscious mice

    PubMed Central

    Chu, Victor; Otero, Jose M; Lopez, Orlando; Morgan, James P; Amende, Ivo; Hampton, Thomas G

    2001-01-01

    Background The rapid increase in the development of mouse models is resulting in a growing demand for non-invasive physiological monitoring of large quantities of mice. Accordingly, we developed a new system for recording electrocardiograms (ECGs) in conscious mice without anesthesia or implants, and created Internet-accessible software for analyzing murine ECG signals. The system includes paw-sized conductive electrodes embedded in a platform configured to record ECGs when 3 single electrodes contact 3 paws. Results With this technique we demonstrated significantly reduced heart rate variability in neonates compared to adult mice. We also demonstrated that female mice exhibit significant ECG differences in comparison to age-matched males, both at baseline and in response to β-adrenergic stimulation. Conclusions The technology we developed enables non-invasive screening of large numbers of mice for ECG changes resulting from genetic, pharmacological, or pathophysiological alterations. Data we obtained non-invasively are not only consistent with what have been reported using invasive and expensive methods, but also demonstrate new findings regarding gender-dependent and age-dependent variations in ECGs in mice. PMID:11476671

  16. Non-invasive diagnosis of advanced fibrosis and cirrhosis.

    PubMed

    Sharma, Suraj; Khalili, Korosh; Nguyen, Geoffrey Christopher

    2014-12-07

    Liver cirrhosis is a common and growing public health problem globally. The diagnosis of cirrhosis portends an increased risk of morbidity and mortality. Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis. However, despite its universal use, liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks. In order to overcome the limitations of liver biopsy, a number of non-invasive techniques have been investigated for the assessment of cirrhosis. This review will focus on currently available non-invasive markers of cirrhosis. The evidence behind the use of these markers will be highlighted, along with an assessment of diagnostic accuracy and performance characteristics of each test. Non-invasive markers of cirrhosis can be radiologic or serum-based. Radiologic techniques based on ultrasound, magnetic resonance imaging and elastography have been used to assess liver fibrosis. Serum-based biomarkers of cirrhosis have also been developed. These are broadly classified into indirect and direct markers. Indirect biomarkers reflect liver function, which may decline with the onset of cirrhosis. Direct biomarkers, reflect extracellular matrix turnover, and include molecules involved in hepatic fibrogenesis. On the whole, radiologic and serum markers of fibrosis correlate well with biopsy scores, especially when excluding cirrhosis or excluding fibrosis. This feature is certainly clinically useful, and avoids liver biopsy in many cases.

  17. DDiT4L promotes autophagy and inhibits pathological cardiac hypertrophy in response to stress.

    PubMed

    Simonson, Bridget; Subramanya, Vinita; Chan, Mun Chun; Zhang, Aifeng; Franchino, Hannabeth; Ottaviano, Filomena; Mishra, Manoj K; Knight, Ashley C; Hunt, Danielle; Ghiran, Ionita; Khurana, Tejvir S; Kontaridis, Maria I; Rosenzweig, Anthony; Das, Saumya

    2017-02-28

    Physiological cardiac hypertrophy, in response to stimuli such as exercise, is considered adaptive and beneficial. In contrast, pathological cardiac hypertrophy that arises in response to pathological stimuli such as unrestrained high blood pressure and oxidative or metabolic stress is maladaptive and may precede heart failure. We found that the transcript encoding DNA damage-inducible transcript 4-like (DDiT4L) was expressed in murine models of pathological cardiac hypertrophy but not in those of physiological cardiac hypertrophy. In cardiomyocytes, DDiT4L localized to early endosomes and promoted stress-induced autophagy through a process involving mechanistic target of rapamycin complex 1 (mTORC1). Exposing cardiomyocytes to various types of pathological stress increased the abundance of DDiT4L, which inhibited mTORC1 but activated mTORC2 signaling. Mice with conditional cardiac-specific overexpression of DDiT4L had mild systolic dysfunction, increased baseline autophagy, reduced mTORC1 activity, and increased mTORC2 activity, all of which were reversed by suppression of transgene expression. Genetic suppression of autophagy also reversed cardiac dysfunction in these mice. Our data showed that DDiT4L may be an important transducer of pathological stress to autophagy through mTOR signaling in the heart and that DDiT4L could be therapeutically targeted in cardiovascular diseases in which autophagy and mTOR signaling play a major role.

  18. Cardiac vagal control and dynamic responses to psychological stress among patients with coronary artery disease.

    PubMed

    Grossman, P; Watkins, L L; Wilhelm, F H; Manolakis, D; Lown, B

    1996-12-15

    Two groups of patients with coronary artery disease who differed in level of cardiac vagal control were compared in their cardiovascular responses to psychological stress. Patients with lower vagal control manifested increased reactions in diastolic blood pressure and rate-pressure product to mental stress and tended to have greater systemic vasoconstriction.

  19. Stress-induced cardiac autonomic reactivity and preclinical atherosclerosis: does arterial elasticity modify the association?

    PubMed

    Chumaeva, Nadja; Hintsanen, Mirka; Pulkki-Råback, Laura; Merjonen, Päivi; Elovainio, Marko; Hintsa, Taina; Juonala, Markus; Kähönen, Mika; Raitakari, Olli T; Keltikangas-Järvinen, Liisa

    2015-01-01

    The effect of acute mental stress on atherosclerosis can be estimated using arterial elasticity measured by carotid artery distensibility (Cdist). We examined the interactive effect of acute stress-induced cardiac reactivity and Cdist to preclinical atherosclerosis assessed by carotid intima-media thickness (IMT) in 58 healthy adults aged 24-39 years participated in the epidemiological Young Finns Study. Cdist and IMT were measured ultrasonographically. Impedance electrocardiography was used to measure acute mental stress-induced cardiac autonomic responses: heart rate (HR), respiratory sinus arrhythmia and pre-ejection period after the mental arithmetic and the public speaking tasks. Interactions between HR reactivity and Cdist in relation to preclinical atherosclerosis were found. The results imply that elevated HR reactivity to acute mental stress is related to less atherosclerosis among healthy participants with higher arterial elasticity. Possibly, increased cardiac reactivity in response to challenging tasks is an adaptive reaction related to better cardiovascular health.

  20. Cardiac oxidative stress in a mouse model of neutral lipid storage disease☆

    PubMed Central

    Schrammel, Astrid; Mussbacher, Marion; Winkler, Sarah; Haemmerle, Guenter; Stessel, Heike; Wölkart, Gerald; Zechner, Rudolf; Mayer, Bernd

    2013-01-01

    Cardiac oxidative stress has been implicated in the pathogenesis of hypertrophy, cardiomyopathy and heart failure. Systemic deletion of the gene encoding adipose triglyceride lipase (ATGL), the enzyme that catalyzes the rate-limiting step of triglyceride lipolysis, results in a phenotype characterized by severe steatotic cardiac dysfunction. The objective of the present study was to investigate a potential role of oxidative stress in cardiac ATGL deficiency. Hearts of mice with global ATGL knockout were compared to those of mice with cardiomyocyte-restricted overexpression of ATGL and to those of wildtype littermates. Our results demonstrate that oxidative stress, measured as lucigenin chemiluminescence, was increased ~ 6-fold in ATGL-deficient hearts. In parallel, cytosolic NADPH oxidase subunits p67phox and p47phox were upregulated 4–5-fold at the protein level. Moreover, a prominent upregulation of different inflammatory markers (tumor necrosis factor α, monocyte chemotactant protein-1, interleukin 6, and galectin-3) was observed in those hearts. Both the oxidative and inflammatory responses were abolished upon cardiomyocyte-restricted overexpression of ATGL. Investigating the effect of oxidative and inflammatory stress on nitric oxide/cGMP signal transduction we observed a ~ 2.5-fold upregulation of soluble guanylate cyclase activity and a ~ 2-fold increase in cardiac tetrahydrobiopterin levels. Systemic treatment of ATGL-deficient mice with the superoxide dismutase mimetic Mn(III)tetrakis (4-benzoic acid) porphyrin did not ameliorate but rather aggravated cardiac oxidative stress. Our data suggest that oxidative and inflammatory stress seems involved in lipotoxic heart disease. Upregulation of soluble guanylate cyclase and cardiac tetrahydrobiopterin might be regarded as counterregulatory mechanisms in cardiac ATGL deficiency. PMID:23867907

  1. Cold Pressor Stress Cardiac Magnetic Resonance Myocardial Flow Reserve Is Not Useful for Detection of Coronary Endothelial Dysfunction in Women with Signs and Symptoms of Ischemia and No Obstructive CAD

    PubMed Central

    Landes, Sofy; Dela Cruz, Sherwin; Wei, Janet; AlBadri, Ahmed; Shufelt, Chrisandra; Mehta, Puja; Thomson, Louise E.; Diniz, Marcio A.; Zhang, Xiao; Petersen, John W.; Anderson, R. David; Pepine, Carl J.; Berman, Daniel S.; Bairey Merz, C. Noel

    2017-01-01

    Background Coronary endothelial function testing using acetylcholine is not routinely available, while non-pharmacological cold pressor testing (CPT) is considered an endothelial stressor. Noninvasive cardiac magnetic resonance imaging (CMRI) myocardial perfusion reserve index (MPRI) can detect coronary microvascular dysfunction (CMD). We evaluated if CPT stress CMRI MPRI could detect invasive coronary endothelial dysfunction. Methods Coronary reactivity testing was performed in 189 women with symptoms and signs of ischemic but no obstructive coronary artery disease as previously described plus CPT stress. Subjects also underwent pharmacologic and CPT stress during CMRI (1.5 T). Statistical analysis comparing CPT MPRI between groups was performed by Welch`s t-test and Mann-Whitney where appropriate. Anderson-Darling test and Levene test were considered to verify the normality and homogeneity of variances assumptions. Correlation analyses between CPT MPRI and both invasive and noninvasive measures of CMD were performed using Spearman correlation. Results While CPT MPRI correlated with pharmacological stress MPRI, it did not correlate with invasive measures of CMD including invasively measured responses to intracoronary (IC) adenosine, IC acetylcholine, CPT, or IC nitroglycerin. Additionally CPT MPRI was not significantly different between subjects with normal compared to abnormal pharm stress MPRI or normal compared to abnormal invasive CMD parameters. Conclusion Despite correlation with pharmacological stress MPRI, non-invasive CPT MPRI does not appear to be useful for detecting CMD in symptomatic women. PMID:28081214

  2. Solving the cardiac hypertrophy riddle: The angiotensin II-mechanical stress connection.

    PubMed

    Zablocki, Daniela; Sadoshima, Junichi

    2013-11-08

    A series of studies conducted 20 years ago, documenting the cardiac hypertrophy phenotype and its underlying signaling mechanism induced by angiotensin II (Ang II) and mechanical stress, showed a remarkable similarity between the effect of the Gαq agonist and that of mechanical forces on cardiac hypertrophy. Subsequent studies confirmed the involvement of autocrine/paracrine mechanisms, including stretch-induced release of Ang II in load-induced cardiac hypertrophy. Recent studies showed that the Ang II type 1 (AT1) receptor is also directly activated by mechanical forces, suggesting that AT1 receptors play an important role in mediating load-induced cardiac hypertrophy through both ligand- and mechanical stress-dependent mechanisms.

  3. Cardiac reactivity to and recovery from acute stress: temporal associations with implicit anxiety.

    PubMed

    Verkuil, Bart; Brosschot, Jos F; Thayer, Julian F

    2014-05-01

    Excessive cardiac responses to stressful events are a risk factor for morbidity and mortality. Adverse cardiac responses are usually attributed to conscious negative stress and emotions. Yet, cardiac responses might also be affected by emotions that are not consciously reported. Here we tested this hypothesis. Sixty participants were randomly allocated to an evaluated speaking stressor or control condition. Trait, state and implicit anxiety were assessed with the State Trait Anxiety Inventory, visual analog scales and the Implicit Association Test for assessing anxiety, with the latter two assessed before and after the stressor. Results showed that the stressor did not significantly affect implicit anxiety. Yet, participants with high implicit anxiety after the stressor had an overall enhanced heart rate and larger stressor-induced decreases in heart rate variability. These associations were independent of conscious anxiety. The implications of the results for a better understanding of excessive cardiac activity are discussed.

  4. Chronic stress and coping among cardiac surgeons: a single center study

    PubMed Central

    Spiliopoulos, Kyriakos; Gansera, Laura; Weiland, Hans Christian; Schuster, Tibor; Eichinger, Walter; Gansera, Brigitte

    2014-01-01

    Introduction Cardiac surgeons stress may impair their quality of life and professional practice. Objective To assess perceived chronic stress and coping strategies among cardiac surgeons. Methods Twenty-two cardiac surgeons answered two self-assessment questionnaires, the Trier Inventory for Chronic Stress and the German SGV for coping strategies. Results Participants mean age was 40±14.1 years and 13 were male; eight were senior physicians and 14 were residents. Mean values for the Trier Inventory for Chronic Stress were within the normal range. Unexperienced physicians had significantly higher levels of dissatisfaction at work, lack of social recognition, and isolation (P<0.05). Coping strategies such as play down, distraction from situation, and substitutional satisfaction were also significantly more frequent among unexperienced surgeons. "Negative" stress-coping strategies occur more often in experienced than in younger colleagues (P=0.029). Female surgeons felt more exposed to overwork (P=0.04) and social stress (P=0.03). Conclusion Cardiac surgeons show a tendency to high perception of chronic stress phenomena and vulnerability for negative coping strategies. PMID:25372902

  5. Reactive Oxygen Species, Endoplasmic Reticulum Stress and Mitochondrial Dysfunction: The Link with Cardiac Arrhythmogenesis

    PubMed Central

    Tse, Gary; Yan, Bryan P.; Chan, Yin W. F.; Tian, Xiao Yu; Huang, Yu

    2016-01-01

    Background: Cardiac arrhythmias represent a significant problem globally, leading to cerebrovascular accidents, myocardial infarction, and sudden cardiac death. There is increasing evidence to suggest that increased oxidative stress from reactive oxygen species (ROS), which is elevated in conditions such as diabetes and hypertension, can lead to arrhythmogenesis. Method: A literature review was undertaken to screen for articles that investigated the effects of ROS on cardiac ion channel function, remodeling and arrhythmogenesis. Results: Prolonged endoplasmic reticulum stress is observed in heart failure, leading to increased production of ROS. Mitochondrial ROS, which is elevated in diabetes and hypertension, can stimulate its own production in a positive feedback loop, termed ROS-induced ROS release. Together with activation of mitochondrial inner membrane anion channels, it leads to mitochondrial depolarization. Abnormal function of these organelles can then activate downstream signaling pathways, ultimately culminating in altered function or expression of cardiac ion channels responsible for generating the cardiac action potential (AP). Vascular and cardiac endothelial cells become dysfunctional, leading to altered paracrine signaling to influence the electrophysiology of adjacent cardiomyocytes. All of these changes can in turn produce abnormalities in AP repolarization or conduction, thereby increasing likelihood of triggered activity and reentry. Conclusion: ROS plays a significant role in producing arrhythmic substrate. Therapeutic strategies targeting upstream events include production of a strong reducing environment or the use of pharmacological agents that target organelle-specific proteins and ion channels. These may relieve oxidative stress and in turn prevent arrhythmic complications in patients with diabetes, hypertension, and heart failure. PMID:27536244

  6. Prediction of human core body temperature using non-invasive measurement methods.

    PubMed

    Niedermann, Reto; Wyss, Eva; Annaheim, Simon; Psikuta, Agnes; Davey, Sarah; Rossi, René Michel

    2014-01-01

    The measurement of core body temperature is an efficient method for monitoring heat stress amongst workers in hot conditions. However, invasive measurement of core body temperature (e.g. rectal, intestinal, oesophageal temperature) is impractical for such applications. Therefore, the aim of this study was to define relevant non-invasive measures to predict core body temperature under various conditions. We conducted two human subject studies with different experimental protocols, different environmental temperatures (10 °C, 30 °C) and different subjects. In both studies the same non-invasive measurement methods (skin temperature, skin heat flux, heart rate) were applied. A principle component analysis was conducted to extract independent factors, which were then used in a linear regression model. We identified six parameters (three skin temperatures, two skin heat fluxes and heart rate), which were included for the calculation of two factors. The predictive value of these factors for core body temperature was evaluated by a multiple regression analysis. The calculated root mean square deviation (rmsd) was in the range from 0.28 °C to 0.34 °C for all environmental conditions. These errors are similar to previous models using non-invasive measures to predict core body temperature. The results from this study illustrate that multiple physiological parameters (e.g. skin temperature and skin heat fluxes) are needed to predict core body temperature. In addition, the physiological measurements chosen in this study and the algorithm defined in this work are potentially applicable as real-time core body temperature monitoring to assess health risk in broad range of working conditions.

  7. Regulation of cardiac function during a cold pressor test in athletes and untrained subjects.

    PubMed

    Ifuku, Hirotoshi; Moriyama, Kayo; Arai, Kuniko; Shiraishi-Hichiwa, Yumiko

    2007-09-01

    By using (dP/dt)/P of carotid artery pulse, a non-invasive index of cardiac contractility, we examined the regulatory mechanism of cardiac function during a cold pressor test in athletes and untrained subjects. Twenty-four healthy subjects (9 athletes, 8 untrained subjects, and 7 hyperreactors of 4 athletes and 3 untrained subjects with a rise of 15 mmHg or greater in systolic and/or diastolic blood pressure) underwent the cold pressor test according to Hines and Brown (Am Heart J 11:1-9, 1936): immersion of the right hand in 4 degrees C water for 1 min. Although mean blood pressure increased during the cold stress in all the groups, cardiac function differed. In athletes, heart rate and cardiac contractility caused cardiac output to increase while total peripheral resistance (TPR) did not change. In untrained subjects, however, heart rate and cardiac contractility tended to decrease cardiac output and thus TPR increased. In hyperreactors, heart rate and cardiac contractility increased during cold stress, and also TPR increased. After the end of the test, heart rate and cardiac contractility decreased only in untrained group. The findings that during a cold pressor test heart rate and cardiac contractility are enhanced in athletes but depressed in untrained subjects indicate that the state of physical training influences cardiac sympathetic neural reactivity to cold stress, except for hyperreactors.

  8. Non-invasive quantification of lower limb mechanical alignment in flexion

    PubMed Central

    Deakin, Angela; Fogg, Quentin A.; Picard, Frederic

    2014-01-01

    Objective Non-invasive navigation techniques have recently been developed to determine mechanical femorotibial alignment (MFTA) in extension. The primary aim of this study was to evaluate the precision and accuracy of an image-free navigation system with new software designed to provide multiple kinematic measurements of the knee. The secondary aim was to test two types of strap material used to attach optical trackers to the lower limb. Methods Seventy-two registrations were carried out on 6 intact embalmed cadaveric specimens (mean age: 77.8 ± 12 years). A validated fabric strap, bone screws and novel rubber strap were used to secure the passive tracker baseplate for four full experiments with each knee. The MFTA angle was measured under the conditions of no applied stress, valgus stress, and varus stress. These measurements were carried out at full extension and at 30°, 40°, 50° and 60° of flexion. Intraclass correlation coefficients, repeatability coefficients, and limits of agreement (LOA) were used to convey precision and agreement in measuring MFTA with respect to each of the independent variables, i.e., degree of flexion, applied coronal stress, and method of tracker fixation. Based on the current literature, a repeatability coefficient and LOA of ≤3° were deemed acceptable. Results The mean fixed flexion for the 6 specimens was 12.8° (range: 6–20°). The mean repeatability coefficient measuring MFTA in extension with screws or fabric strapping of the baseplate was ≤2°, compared to 2.3° using rubber strapping. When flexing the knee, MFTA measurements taken using screws or fabric straps remained precise (repeatability coefficient ≤3°) throughout the tested range of flexion (12.8–60°); however, using rubber straps, the repeatability coefficient was >3° beyond 50° flexion. In general, applying a varus/valgus stress while measuring MFTA decreased precision beyond 40° flexion. Using fabric strapping, excellent repeatability

  9. Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758).

    PubMed

    Ferreira, João C P; Fujihara, Caroline J; Fruhvald, Erika; Trevisol, Eduardo; Destro, Flavia C; Teixeira, Carlos R; Pantoja, José C F; Schmidt, Elizabeth M S; Palme, Rupert

    2015-01-01

    Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots' physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3-9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural

  10. Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758)

    PubMed Central

    Ferreira, João C. P.; Fujihara, Caroline J.; Fruhvald, Erika; Trevisol, Eduardo; Destro, Flavia C.; Teixeira, Carlos R.; Pantoja, José C. F.; Schmidt, Elizabeth M. S.; Palme, Rupert

    2015-01-01

    Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots’ physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3–9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural

  11. Non-invasive techniques for determining musculoskeleton body composition

    SciTech Connect

    Cohn, S.H.

    1984-01-01

    In vivo neutron activation analysis, combined with gamma spectrometry, has ushered in a new era of clinical diagnosis and evaluation of therapies, as well as investigation into and modelling of body composition in both normal individuals and patients suffering from various diseases and dysfunctions. Body composition studies have provided baseline data on such vital constituents as nitrogen, potassium and calcium. The non-invasive measurement techniques are particularly suitable for study of the musculo-skeletal changes in body composition. Of particular relevance here is the measurement of calcium loss in astronauts during prolonged space flights.

  12. Non-invasive pulmonary function test on Morquio patients.

    PubMed

    Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G; Theroux, Mary; Bober, Michael B; Oldham, Helen M; Orii, Tadao; Shaffer, Thomas H

    2015-08-01

    In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and

  13. Towards a smart non-invasive fluid loss measurement system.

    PubMed

    Suryadevara, N K; Mukhopadhyay, S C; Barrack, L

    2015-04-01

    In this article, a smart wireless sensing non-invasive system for estimating the amount of fluid loss, a person experiences while physical activity is presented. The system measures three external body parameters, Heart Rate, Galvanic Skin Response (GSR, or skin conductance), and Skin Temperature. These three parameters are entered into an empirically derived formula along with the user's body mass index, and estimation for the amount of fluid lost is determined. The core benefit of the developed system is the affluence usage in combining with smart home monitoring systems to care elderly people in ambient assisted living environments as well in automobiles to monitor the body parameters of a motorist.

  14. Advances in non-invasive imaging of intracranial vascular disease.

    PubMed Central

    Jäger, H. R.; Grieve, J. P.

    2000-01-01

    Intra-arterial catheter angiography has, in the past, been the mainstay for the investigation of intracranial vascular disease. It is, however, invasive, usually requires in-patients admission, and is associated with a rate of neurological complications between 1% and 3%. In recent years, magnetic resonance angiography (MRA) and CT angiography (CTA) have emerged as non-invasive alternatives for imaging blood vessels and have made a significant impact on neuroradiological investigations. It is the purpose of this article to explain the basic technical principles of these two methods and to give an overview of their current clinical applications. PMID:10700757

  15. Kaempferol Attenuates Cardiac Hypertrophy via Regulation of ASK1/MAPK Signaling Pathway and Oxidative Stress.

    PubMed

    Feng, Hong; Cao, Jianlei; Zhang, Guangyu; Wang, Yanggan

    2017-02-20

    Kaempferol has been demonstrated to provide benefits for the treatment of atherosclerosis, coronary heart disease, hyperlipidemia, and diabetes through its antioxidant and anti-inflammatory properties. However, its role in cardiac hypertrophy remains to be elucidated. The aim of our study was to investigate the effects of kaempferol on cardiac hypertrophy and the underlying mechanism. Mice subjected to aorta banding were treated with or without kaempferol (100 mg/kg/d, p. o.) for 6 weeks. Echocardiography was performed to evaluate cardiac function. Mice hearts were collected for pathological observation and molecular mechanism investigation. H9c2 cardiomyocytes were stimulated with or without phenylephrine for in vitro study. Kaempferol significantly attenuated cardiac hypertrophy induced by aorta banding as evidenced by decreased cardiomyocyte areas and interstitial fibrosis, accompanied with improved cardiac functions and decreased apoptosis. The ASK1/MAPK signaling pathways (JNK1/2 and p38) were markedly activated in the aorta banding mouse heart but inhibited by kaempferol treatment. In in vitro experiments, kaempferol also inhibited the activity of ASK1/JNK1/2/p38 signaling pathway and the enlargement of H9c2 cardiomyocytes. Furthermore, our study revealed that kaempferol could protect the mouse heart and H9c2 cells from pathological oxidative stress. Our investigation indicated that treatment with kaempferol protects against cardiac hypertrophy, and its cardioprotection may be partially explained by the inhibition of the ASK1/MAPK signaling pathway and the regulation of oxidative stress.

  16. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water

    PubMed Central

    Chung, SH; Cerussi, AE; Merritt, SI; Ruth, J; Tromberg, BJ

    2012-01-01

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R = 0.96) with a difference of 1.1 ± 0.91 °C over a range of 28–48 °C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics. PMID:20551502

  17. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water.

    PubMed

    Chung, S H; Cerussi, A E; Merritt, S I; Ruth, J; Tromberg, B J

    2010-07-07

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R=0.96) with a difference of 1.1+/-0.91 degrees C over a range of 28-48 degrees C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics.

  18. Use of the single-breath method of estimating cardiac output during exercise-stress testing.

    NASA Technical Reports Server (NTRS)

    Buderer, M. C.; Rummel, J. A.; Sawin, C. F.; Mauldin, D. G.

    1973-01-01

    The single-breath cardiac output measurement technique of Kim et al. (1966) has been modified for use in obtaining cardiac output measurements during exercise-stress tests on Apollo astronauts. The modifications involve the use of a respiratory mass spectrometer for data acquisition and a digital computer program for data analysis. The variation of the modified method for triplicate steady-state cardiac output measurements was plus or minus 1 liter/min. The combined physiological and methodological variation seen during a set of three exercise tests on a series of subjects was 1 to 2.5 liter/min. Comparison of the modified method with the direct Fick technique showed that although the single-breath values were consistently low, the scatter of data was small and the correlation between the two methods was high. Possible reasons for the low single-breath cardiac output values are discussed.

  19. Salubrinal Alleviates Pressure Overload-Induced Cardiac Hypertrophy by Inhibiting Endoplasmic Reticulum Stress Pathway

    PubMed Central

    Rani, Shilpa; Sreenivasaiah, Pradeep Kumar; Cho, Chunghee; Kim, Do Han

    2017-01-01

    Pathological hypertrophy of the heart is closely associated with endoplasmic reticulum stress (ERS), leading to maladaptations such as myocardial fibrosis, induction of apoptosis, and cardiac dysfunctions. Salubrinal is a known selective inhibitor of protein phosphatase 1 (PP1) complex involving dephosphorylation of phospho-eukaryotic translation initiation factor 2 subunit (p-eIF2)-α, the key signaling process in the ERS pathway. In this study, the effects of salubrinal were examined on cardiac hypertrophy using the mouse model of transverse aortic constriction (TAC) and cell model of neonatal rat ventricular myocytes (NRVMs). Treatment of TAC-induced mice with salubrinal (0.5 mg·kg−1·day−1) alleviated cardiac hypertrophy and tissue fibrosis. Salubrinal also alleviated hypertrophic growth in endothelin 1 (ET1)-treated NRVMs. Therefore, the present results suggest that salubrinal may be a potentially efficacious drug for treating pathological cardiac remodeling. PMID:28152298

  20. Clinical role of non-invasive assessment of portal hypertension.

    PubMed

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-07

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field.

  1. Infrared thermography: A non-invasive window into thermal physiology.

    PubMed

    Tattersall, Glenn J

    2016-12-01

    Infrared thermography is a non-invasive technique that measures mid to long-wave infrared radiation emanating from all objects and converts this to temperature. As an imaging technique, the value of modern infrared thermography is its ability to produce a digitized image or high speed video rendering a thermal map of the scene in false colour. Since temperature is an important environmental parameter influencing animal physiology and metabolic heat production an energetically expensive process, measuring temperature and energy exchange in animals is critical to understanding physiology, especially under field conditions. As a non-contact approach, infrared thermography provides a non-invasive complement to physiological data gathering. One caveat, however, is that only surface temperatures are measured, which guides much research to those thermal events occurring at the skin and insulating regions of the body. As an imaging technique, infrared thermal imaging is also subject to certain uncertainties that require physical modelling, which is typically done via built-in software approaches. Infrared thermal imaging has enabled different insights into the comparative physiology of phenomena ranging from thermogenesis, peripheral blood flow adjustments, evaporative cooling, and to respiratory physiology. In this review, I provide background and guidelines for the use of thermal imaging, primarily aimed at field physiologists and biologists interested in thermal biology. I also discuss some of the better known approaches and discoveries revealed from using thermal imaging with the objective of encouraging more quantitative assessment.

  2. Influence of hemoglobin on non-invasive optical bilirubin sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Gong, Qiliang; Zou, Da; Xu, Kexin

    2012-03-01

    Since the abnormal metabolism of bilirubin could lead to diseases in the human body, especially the jaundice which is harmful to neonates. Traditional invasive measurements are difficult to be accepted by people because of pain and infection. Therefore, the real-time and non-invasive measurement of bilirubin is of great significance. However, the accuracy of currently transcutaneous bilirubinometry(TcB) is generally not high enough, and affected by many factors in the human skin, mostly by hemoglobin. In this talk, absorption spectra of hemoglobin and bilirubin have been collected and analyzed, then the Partial Least Squares (PLS) models have been built. By analyzing and comparing the Correlation and Root Mean Square Error of Prediction(RMSEP), the results show that the Correlation of bilirubin solution model is larger than that of the mixture solution added with hemoglobin, and its RMSEP value is smaller than that of mixture solution. Therefore, hemoglobin has influences on the non-invasive optical bilirubin sensing. In next step, it is necessary to investigate how to eliminate the influence.

  3. Modulation of Untruthful Responses with Non-Invasive Brain Stimulation

    PubMed Central

    Fecteau, Shirley; Boggio, Paulo; Fregni, Felipe; Pascual-Leone, Alvaro

    2013-01-01

    Deceptive abilities have long been studied in relation to personality traits. More recently, studies explored the neural substrates associated with deceptive skills suggesting a critical role of the prefrontal cortex. Here we investigated whether non-invasive brain stimulation over the dorsolateral prefrontal cortex (DLPFC) could modulate generation of untruthful responses about subject’s personal life across contexts (i.e., deceiving on guilt-free questions on daily activities; generating previously memorized lies about past experience; and producing spontaneous lies about past experience), as well as across modality responses (verbal and motor responses). Results reveal that real, but not sham, transcranial direct current stimulation (tDCS) over the DLPFC can reduce response latency for untruthful over truthful answers across contexts and modality responses. Also, contexts of lies seem to incur a different hemispheric laterality. These findings add up to previous studies demonstrating that it is possible to modulate some processes involved in generation of untruthful answers by applying non-invasive brain stimulation over the DLPFC and extend these findings by showing a differential hemispheric contribution of DLPFCs according to contexts. PMID:23550273

  4. Non-invasive primate head restraint using thermoplastic masks

    PubMed Central

    Drucker, Caroline B.; Carlson, Monica L.; Toda, Koji; DeWind, Nicholas K.; Platt, Michael L.

    2015-01-01

    Background The success of many neuroscientific studies depends upon adequate head fixation of awake, behaving animals. Typically, this is achieved by surgically affixing a head-restraint prosthesis to the skull. New Method Here we report the use of thermoplastic masks to non-invasively restrain monkeys’ heads. Mesh thermoplastic sheets become pliable when heated and can then be molded to an individual monkey’s head. After cooling, the custom mask retains this shape indefinitely for day-to-day use. Results We successfully trained rhesus macaques (Macaca mulatta) to perform cognitive tasks while wearing thermoplastic masks. Using these masks, we achieved a level of head stability sufficient for high-resolution eye-tracking and intracranial electrophysiology. Comparison with Existing Method Compared with traditional head-posts, we find that thermoplastic masks perform at least as well during infrared eye-tracking and single-neuron recordings, allow for clearer magnetic resonance image acquisition, enable freer placement of a transcranial magnetic stimulation coil, and impose lower financial and time costs on the lab. Conclusions We conclude that thermoplastic masks are a viable non-invasive form of primate head restraint that enable a wide range of neuroscientific experiments. PMID:26112334

  5. Clinical role of non-invasive assessment of portal hypertension

    PubMed Central

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-01

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field. PMID:28104976

  6. Evolving strategies for liver fibrosis staging: Non-invasive assessment

    PubMed Central

    Stasi, Cristina; Milani, Stefano

    2017-01-01

    Transient elastography and the acoustic radiation force impulse techniques may play a pivotal role in the study of liver fibrosis. Some studies have shown that elastography can detect both the progression and regression of fibrosis. Similarly, research results have been analysed and direct and indirect serum markers of hepatic fibrosis have shown high diagnostic accuracy for advanced fibrosis/cirrhosis. The prognosis of different stages of cirrhosis is well established and various staging systems have been proposed, largely based on clinical data. However, it is still unknown if either non-invasive markers of liver fibrosis or elastography may contribute to a more accurate staging of liver cirrhosis, in terms of prognosis and fibrosis regression after effective therapy. In fact, not enough studies have shown both the fibrosis regression in different cirrhosis stages and the point beyond which the prognosis does not change - even in the event of fibrosis regression. Therefore, future studies are needed to validate non-invasive methods in predicting the different phases of liver cirrhosis. PMID:28127192

  7. Non-invasive diagnosis of liver fibrosis and cirrhosis.

    PubMed

    Lurie, Yoav; Webb, Muriel; Cytter-Kuint, Ruth; Shteingart, Shimon; Lederkremer, Gerardo Z

    2015-11-07

    The evaluation and follow up of liver fibrosis and cirrhosis have been traditionally performed by liver biopsy. However, during the last 20 years, it has become evident that this "gold-standard" is imperfect; even according to its proponents, it is only "the best" among available methods. Attempts at uncovering non-invasive diagnostic tools have yielded multiple scores, formulae, and imaging modalities. All are better tolerated, safer, more acceptable to the patient, and can be repeated essentially as often as required. Most are much less expensive than liver biopsy. Consequently, their use is growing, and in some countries the number of biopsies performed, at least for routine evaluation of hepatitis B and C, has declined sharply. However, the accuracy and diagnostic value of most, if not all, of these methods remains controversial. In this review for the practicing physician, we analyze established and novel biomarkers and physical techniques. We may be witnessing in recent years the beginning of the end of the first phase for the development of non-invasive markers. Early evidence suggests that they might be at least as good as liver biopsy. Novel experimental markers and imaging techniques could produce a dramatic change in diagnosis in the near future.

  8. Non-invasive diagnostic imaging of colorectal liver metastases

    PubMed Central

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-01-01

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs. PMID:26217455

  9. Non-invasive diagnostic imaging of colorectal liver metastases.

    PubMed

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-07-28

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

  10. Non-invasive assessment of the liver using imaging

    NASA Astrophysics Data System (ADS)

    Thorling Thompson, Camilla; Wang, Haolu; Liu, Xin; Liang, Xiaowen; Crawford, Darrell H.; Roberts, Michael S.

    2016-12-01

    Chronic liver disease causes 2,000 deaths in Australia per year and early diagnosis is crucial to avoid progression to cirrhosis and end stage liver disease. There is no ideal method to evaluate liver function. Blood tests and liver biopsies provide spot examinations and are unable to track changes in function quickly. Therefore better techniques are needed. Non-invasive imaging has the potential to extract increased information over a large sampling area, continuously tracking dynamic changes in liver function. This project aimed to study the ability of three imaging techniques, multiphoton and fluorescence lifetime imaging microscopy, infrared thermography and photoacoustic imaging, in measuring liver function. Collagen deposition was obvious in multiphoton and fluorescence lifetime imaging in fibrosis and cirrhosis and comparable to conventional histology. Infrared thermography revealed a significantly increased liver temperature in hepatocellular carcinoma. In addition, multiphoton and fluorescence lifetime imaging and photoacoustic imaging could both track uptake and excretion of indocyanine green in rat liver. These results prove that non-invasive imaging can extract crucial information about the liver continuously over time and has the potential to be translated into clinic in the assessment of liver disease.

  11. Visual memory improved by non-invasive brain stimulation.

    PubMed

    Chi, Richard P; Fregni, Felipe; Snyder, Allan W

    2010-09-24

    Our visual memories are susceptible to errors, but less so in people who have a more literal cognitive style. This inspired us to attempt to improve visual memory with non-invasive brain stimulation. We applied 13 min of bilateral transcranial direct current stimulation (tDCS) to the anterior temporal lobes. Our stimulation protocol included 3 conditions, each with 12 neurotypical participants: (i) left cathodal stimulation together with right anodal stimulation, (ii) left anodal stimulation together with right cathodal stimulation, and (iii) sham (control) stimulation. Only participants who received left cathodal stimulation (decrease in excitability) together with right anodal stimulation (increase in excitability) showed an improvement in visual memory. This 110% improvement in visual memory was similar to the advantage people with autism, who are known to be more literal, show over normal people in the identical visual task. Importantly, participants receiving stimulation of the opposite polarity (left anodal together with right cathodal stimulation) failed to show any change in memory performance. This is the first demonstration that visual memory can be enhanced in healthy people using non-invasive brain stimulation.

  12. Rationale and Design of the Dual Energy Computed Tomography for Ischemia Determination Compared to “Gold Standard” Non-invasive and Invasive Techniques (DECIDE-Gold): A Multicenter International Efficacy Diagnostic Study of Rest-Stress Dual-Energy Computed Tomography Angiography with Perfusion

    PubMed Central

    Truong, Quynh A.; Knaapen, Paul; Pontone, Gianluca; Andreini, Daniele; Leipsic, Jonathon; Carrascosa, Patricia; Lu, Bin; Branch, Kelley; Raman, Subha; Bloom, Stephen; Min, James K.

    2014-01-01

    BACKGROUND Dual-energy CT (DECT) has potential to improve myocardial perfusion for physiologic assessment of coronary artery disease (CAD). Diagnostic performance of rest-stress DECT perfusion (DECTP) is unknown. OBJECTIVE DECIDE-Gold is a prospective multicenter study to evaluate the accuracy of DECT to detect hemodynamic (HD) significant CAD, as compared to fractional flow reserve (FFR) as a reference standard. METHODS Eligible participants are subjects with symptoms of CAD referred for invasive coronary angiography (ICA). Participants will undergo DECTP, which will be performed by pharmacological stress, and participants will subsequently proceed to ICA and FFR. HD-significant CAD will be defined as FFR ≥ 0.80. In those undergoing myocardial stress imaging (MPI) by positron emission tomography (PET), single photon emission computed tomography (SPECT) or cardiac magnetic resonance (CMR) imaging, ischemia will be graded by % ischemic myocardium. Blinded core laboratory interpretation will be performed for CCTA, DECTP, MPI, ICA and FFR. RESULTS Primary endpoint is accuracy of DECTP to detect ≥ 1 HD-significant stenosis at the subject-level when compared to FFR. Secondary and tertiary endpoints are accuracies of combinations of DECTP at the subject and vessel levels compared to FFR and MPI. CONCLUSION DECIDE-Gold will determine the performance of DECTP for diagnosing ischemia. PMID:25549826

  13. Aging induces cardiac diastolic dysfunction, oxidative stress, accumulation of advanced glycation endproducts and protein modification.

    PubMed

    Li, Shi-Yan; Du, Min; Dolence, E Kurt; Fang, Cindy X; Mayer, Gabriele E; Ceylan-Isik, Asli F; LaCour, Karissa H; Yang, Xiaoping; Wilbert, Christopher J; Sreejayan, Nair; Ren, Jun

    2005-04-01

    Evidence suggests that aging, per se, is a major risk factor for cardiac dysfunction. Oxidative modification of cardiac proteins by non-enzymatic glycation, i.e. advanced glycation endproducts (AGEs), has been implicated as a causal factor in the aging process. This study was designed to examine the role of aging on cardiomyocyte contractile function, cardiac protein oxidation and oxidative modification. Mechanical properties were evaluated in ventricular myocytes from young (2-month) and aged (24-26-month) mice using a MyoCam system. The mechanical indices evaluated were peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR90) and maximal velocity of shortening/relengthening (+/- dL/dt). Oxidative stress and protein damage were evaluated by glutathione and glutathione disulfide (GSH/GSSG) ratio and protein carbonyl content, respectively. Activation of NAD(P)H oxidase was determined by immunoblotting. Aged myocytes displayed a larger cell cross-sectional area, prolonged TR90, and normal PS, +/- dL/dt and TPS compared with young myocytes. Aged myocytes were less tolerant of high stimulus frequency (from 0.1 to 5 Hz) compared with young myocytes. Oxidative stress and protein oxidative damage were both elevated in the aging group associated with significantly enhanced p47phox but not gp91phox expression. In addition, level of cardiac AGEs was approximately 2.5-fold higher in aged hearts than young ones determined by AGEs-ELISA. A group of proteins with a molecular range between 50 and 75 kDa with pI of 4-7 was distinctively modified in aged heart using one- or two-dimension SDS gel electrophoresis analysis. These data demonstrate cardiac diastolic dysfunction and reduced stress tolerance in aged cardiac myocytes, which may be associated with enhanced cardiac oxidative damage, level of AGEs and protein modification by AGEs.

  14. The Impact of Stress Hormones on Post-traumatic Stress Disorders Symptoms and Memory in Cardiac Surgery Patients.

    PubMed

    Porhomayon, Jahan; Kolesnikov, Sergei; Nader, Nader D

    2014-01-01

    The relationship and interactions between stress hormones and post-traumatic stress disorder (PTSD) are well established from both animal and human research studies. This interaction is especially important in the post-operative phase of cardiac surgery where the development of PTSD symptoms will result in increased morbidity and mortality and prolong length of stay for critically ill cardiac surgery patients. Cardiopulmonary bypass itself will independently result in massive inflammation response and release of stress hormones in the perioperative period. Glucocorticoid may reduce this response and result in reduction of PTSD symptom clusters and therefore improve health outcome. In this review, we plan to conduct a systemic review and analysis of the literatures on this topic.

  15. Feasibility of Using Wideband Microwave System for Non-Invasive Detection and Monitoring of Pulmonary Oedema

    NASA Astrophysics Data System (ADS)

    Rezaeieh, S. Ahdi; Zamani, A.; Bialkowski, K. S.; Mahmoud, A.; Abbosh, A. M.

    2015-09-01

    Pulmonary oedema is a common manifestation of various fatal diseases that can be caused by cardiac or non-cardiac syndromes. The accumulated fluid has a considerably higher dielectric constant compared to lungs’ tissues, and can thus be detected using microwave techniques. Therefore, a non-invasive microwave system for the early detection of pulmonary oedema is presented. It employs a platform in the form of foam-based bed that contains two linear arrays of wideband antennas covering the band 0.7-1 GHz. The platform is designed such that during the tests, the subject lays on the bed with the back of the torso facing the antenna arrays. The antennas are controlled using a switching network that is connected to a compact network analyzer. A novel frequency-based imaging algorithm is used to process the recorded signals and generate an image of the torso showing any accumulated fluids in the lungs. The system is verified on an artificial torso phantom, and animal organs. As a feasibility study, preclinical tests are conducted on healthy subjects to determinate the type of obtained images, the statistics and threshold levels of their intensity to differentiate between healthy and unhealthy subjects.

  16. Feasibility of Using Wideband Microwave System for Non-Invasive Detection and Monitoring of Pulmonary Oedema

    PubMed Central

    Rezaeieh, S. Ahdi; Zamani, A.; Bialkowski, K. S.; Mahmoud, A.; Abbosh, A. M.

    2015-01-01

    Pulmonary oedema is a common manifestation of various fatal diseases that can be caused by cardiac or non-cardiac syndromes. The accumulated fluid has a considerably higher dielectric constant compared to lungs’ tissues, and can thus be detected using microwave techniques. Therefore, a non-invasive microwave system for the early detection of pulmonary oedema is presented. It employs a platform in the form of foam-based bed that contains two linear arrays of wideband antennas covering the band 0.7–1 GHz. The platform is designed such that during the tests, the subject lays on the bed with the back of the torso facing the antenna arrays. The antennas are controlled using a switching network that is connected to a compact network analyzer. A novel frequency-based imaging algorithm is used to process the recorded signals and generate an image of the torso showing any accumulated fluids in the lungs. The system is verified on an artificial torso phantom, and animal organs. As a feasibility study, preclinical tests are conducted on healthy subjects to determinate the type of obtained images, the statistics and threshold levels of their intensity to differentiate between healthy and unhealthy subjects. PMID:26365299

  17. Taxifolin protects against cardiac hypertrophy and fibrosis during biomechanical stress of pressure overload

    SciTech Connect

    Guo, Haipeng; Zhang, Xin; Cui, Yuqian; Zhou, Heng; Xu, Dachun; Shan, Tichao; Zhang, Fan; Guo, Yuan; Chen, Yuguo; Wu, Dawei

    2015-09-01

    Cardiac hypertrophy is a key pathophysiological component to biomechanical stress, which has been considered to be an independent and predictive risk factor for adverse cardiovascular events. Taxifolin (TAX) is a typical plant flavonoid, which has long been used clinically for treatment of cardiovascular and cerebrovascular diseases. However, very little is known about whether TAX can influence the development of cardiac hypertrophy. In vitro studies, we found that TAX concentration-dependently inhibited angiotensin II (Ang II) induced hypertrophy and protein synthesis in cardiac myocytes. Then we established a mouse model by transverse aortic constriction (TAC) to further confirm our findings. It was demonstrated that TAX prevented pressure overload induced cardiac hypertrophy in mice, as assessed by ventricular mass/body weight, echocardiographic parameters, myocyte cross-sectional area, and the expression of ANP, BNP and β-MHC. The excess production of reactive oxygen species (ROS) played critical role in the development of cardiac hypertrophy. TAX arrested oxidative stress and decreased the expression of 4-HNE induced by pressure overload. Moreover, TAX negatively modulated TAC-induced phosphorylation of ERK1/2 and JNK1/2. Further studies showed that TAX significantly attenuated left ventricular fibrosis and collagen synthesis through abrogating the phosphorylation of Smad2 and Smad2/3 nuclear translocation. These results demonstrated that TAX could inhibit cardiac hypertrophy and attenuate ventricular fibrosis after pressure overload. These beneficial effects were at least through the inhibition of the excess production of ROS, ERK1/2, JNK1/2 and Smad signaling pathways. Therefore, TAX might be a potential candidate for the treatment of cardiac hypertrophy and fibrosis. - Highlights: • We focus on the protective effect of taxifolin on cardiac remodeling. • Taxifolin inhibited cardiac hypertrophy and attenuated ventricular fibrosis. • Taxifolin

  18. In-vivo validation of a new non-invasive continuous ventricular stroke volume monitoring system in an animal model

    PubMed Central

    2011-01-01

    Introduction Recently, a non-invasive, continuous ventricular stroke volume monitoring system using skin electrodes has been developed. In contrast to impedance-based methods, the new technique (ventricular field recognition) enables measurement of changes in ventricular volume. A prototype using this new method was built (the hemologic cardiac profiler, HCP) and validated against a reference method in a pig model during variations in cardiac output. Methods In six Dalland pigs, cardiac output was simultaneously measured with the HCP (CO-HCP), and an invasive ultrasonic flow-probe around the ascending aorta (CO-FP). Variations in CO were achieved by change in ventricular loading conditions, cardiac pacing, and dobutamine administration. Data were analysed according to Bland-Altman analysis and Pearson's correlation. Results Pearson's correlation between the CO-HCP and the CO-FP was r = 0.978. Bland-Altman analysis showed a bias of - 0.114 L/minute, and a variability of the bias (2 standard deviations, 2SD) of 0.55 L/minute. Conclusions The results of the present study demonstrate that CO-HCP is comparable to CO-FP in an animal model of cardiac output measurements during a wide variation of CO. Therefore, the HCP has the potential to become a clinical applicable cardiac output monitor. PMID:21745380

  19. In vivo non-invasive multiphoton tomography of human skin

    NASA Astrophysics Data System (ADS)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  20. Non-invasive cerebellar stimulation--a consensus paper.

    PubMed

    Grimaldi, G; Argyropoulos, G P; Boehringer, A; Celnik, P; Edwards, M J; Ferrucci, R; Galea, J M; Groiss, S J; Hiraoka, K; Kassavetis, P; Lesage, E; Manto, M; Miall, R C; Priori, A; Sadnicka, A; Ugawa, Y; Ziemann, U

    2014-02-01

    The field of neurostimulation of the cerebellum either with transcranial magnetic stimulation (TMS; single pulse or repetitive (rTMS)) or transcranial direct current stimulation (tDCS; anodal or cathodal) is gaining popularity in the scientific community, in particular because these stimulation techniques are non-invasive and provide novel information on cerebellar functions. There is a consensus amongst the panel of experts that both TMS and tDCS can effectively influence cerebellar functions, not only in the motor domain, with effects on visually guided tracking tasks, motor surround inhibition, motor adaptation and learning, but also for the cognitive and affective operations handled by the cerebro-cerebellar circuits. Verbal working memory, semantic associations and predictive language processing are amongst these operations. Both TMS and tDCS modulate the connectivity between the cerebellum and the primary motor cortex, tuning cerebellar excitability. Cerebellar TMS is an effective and valuable method to evaluate the cerebello-thalamo-cortical loop functions and for the study of the pathophysiology of ataxia. In most circumstances, DCS induces a polarity-dependent site-specific modulation of cerebellar activity. Paired associative stimulation of the cerebello-dentato-thalamo-M1 pathway can induce bidirectional long-term spike-timing-dependent plasticity-like changes of corticospinal excitability. However, the panel of experts considers that several important issues still remain unresolved and require further research. In particular, the role of TMS in promoting cerebellar plasticity is not established. Moreover, the exact positioning of electrode stimulation and the duration of the after effects of tDCS remain unclear. Future studies are required to better define how DCS over particular regions of the cerebellum affects individual cerebellar symptoms, given the topographical organization of cerebellar symptoms. The long-term neural consequences of non-invasive

  1. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    PubMed Central

    Antonacci, Giuseppe; Braakman, Sietse

    2016-01-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p < 0.0001) and the surrounding cytoplasm (p < 0.0001). Moreover, we demonstrate the mechanical response of cells to Latrunculin-A, a drug that reduces cell stiffness by preventing cytoskeletal assembly. Our technique can therefore generate valuable insights into cellular biomechanics and its role in pathophysiology. PMID:27845411

  2. Non-Invasive Tension Measurement Devices for Parachute Cordage

    NASA Technical Reports Server (NTRS)

    Litteken, Douglas A.; Daum, Jared S.

    2016-01-01

    The need for lightweight and non-intrusive tension measurements has arisen alongside the development of high-fidelity computer models of textile and fluid dynamics. In order to validate these computer models, data must be gathered in the operational environment without altering the design, construction, or performance of the test article. Current measurement device designs rely on severing a cord and breaking the load path to introduce a load cell. These load cells are very reliable, but introduce an area of high stiffness in the load path, directly affecting the structural response, adding excessive weight, and possibly altering the dynamics of the parachute during a test. To capture the required data for analysis validation without affecting the response of the system, non-invasive measurement devices have been developed and tested by NASA. These tension measurement devices offer minimal impact to the mass, form, fit, and function of the test article, while providing reliable, axial tension measurements for parachute cordage.

  3. Non-invasive ventilation in acute cardiogenic pulmonary oedema

    PubMed Central

    Agarwal, R; Aggarwal, A; Gupta, D; Jindal, S

    2005-01-01

    Non-invasive ventilation (NIV) is the delivery of assisted mechanical ventilation to the lungs, without the use of an invasive endotracheal airway. NIV has revolutionised the management of patients with various forms of respiratory failure. It has decreased the need for invasive mechanical ventilation and its attendant complications. Cardiogenic pulmonary oedema (CPO) is a common medical emergency, and NIV has been shown to improve both physiological and clinical outcomes. From the data presented herein, it is clear that there is sufficiently high level evidence to favour the use of continuous positive airway pressure (CPAP), and that the use of CPAP in patients with CPO decreases intubation rate and improves survival (number needed to treat seven and eight respectively). However, there is insufficient evidence to recommend the use of bilevel positive airway pressure (BiPAP), probably the exception being patients with hypercapnic CPO. More trials are required to conclusively define the role of BiPAP in CPO. PMID:16210459

  4. Moral Enhancement Using Non-invasive Brain Stimulation

    PubMed Central

    Darby, R. Ryan; Pascual-Leone, Alvaro

    2017-01-01

    Biomedical enhancement refers to the use of biomedical interventions to improve capacities beyond normal, rather than to treat deficiencies due to diseases. Enhancement can target physical or cognitive capacities, but also complex human behaviors such as morality. However, the complexity of normal moral behavior makes it unlikely that morality is a single capacity that can be deficient or enhanced. Instead, our central hypothesis will be that moral behavior results from multiple, interacting cognitive-affective networks in the brain. First, we will test this hypothesis by reviewing evidence for modulation of moral behavior using non-invasive brain stimulation. Next, we will discuss how this evidence affects ethical issues related to the use of moral enhancement. We end with the conclusion that while brain stimulation has the potential to alter moral behavior, such alteration is unlikely to improve moral behavior in all situations, and may even lead to less morally desirable behavior in some instances. PMID:28275345

  5. An inverse method for non-invasive viscosity measurements

    NASA Astrophysics Data System (ADS)

    Fullana, J.-M.; Dispot, N.; Flaud, P.; Rossi, M.

    2007-04-01

    A procedure is presented which allows to compute in a non-invasive manner, blood viscosity through flow measurements obtained at a fixed vessel cross-section. The data set is made of measurements (artery radius and spatially discrete velocity profiles) performed at given time intervals for which the signal to noise ratio is typical of U.S. Doppler velocimetry in clinical situation. This identification approach is based on the minimization, through a backpropagation algorithm, of a cost function quantifying the distance between numerical data obtained through Navier-Stokes simulations and experimental measurements. Since this cost function implicitly depends on the value of viscosity used in numerical simulations, its minimization determines an effective viscosity which is shown to be robust to measurement errors and sampling time. Such an approach is shown to work in an in vitro experiment, and seems to be suitable for in vivo measurements of viscosity by the atraumatic techniques of Doppler echography.

  6. Hybrid CARS for Non-Invasive Blood Glucose Monitoring

    NASA Astrophysics Data System (ADS)

    Wang, Xi; Pestov, Dmitry; Zhang, Aihua; Murawski, Robert; Sokolov, Alexei; Welch, George; Laane, Jaan; Scully, Marlan

    2007-10-01

    We develop a spectroscopy technique that combines the advantages of both the frequency-resolved coherent anti-Stokes Raman scattering (CARS) and the time-resolved CARS. We use broadband preparation pulses to get an instantaneous coherent excitation of multiplex molecular vibration levels and subsequent optically shaped time-delayed narrowband probing pulse to detect these vibrations. This technique can suppress the nonresonant background and retrieve the molecular fingerprint signal efficiently and rapidly. We employ this technique to glucose detection, the final goal of which is accurate, non-invasive (i.e. painless) and continuous monitoring of blood glucose concentration in the Diabetes diagnosis to replace the current glucose measurement process, which requires painful fingerpricks and therefore cannot be performed more than a few times a day. We have gotten the CARS spectra of glucose aqueous solution down to 2 mM.

  7. Non-invasive assessment of phonatory and respiratory dynamics.

    PubMed

    LaBlance, G R; Steckol, K F; Cooper, M H

    1991-10-01

    Evaluation of vocal pathology and the accompanying dysphonia should include an assessment of laryngeal structure and mobility as well as respiratory dynamics. Laryngeal structure is best observed through laryngoscopy which provides an accurate assessment of the tissues and their mobility. Respiratory measures of lung volume, air-flow and pressure, and breathing dynamics are typically determined via spirometry and pneumotachography. While the above are traditional invasive procedures which interfere with normal speech production, recent advances in electronic technology have resulted in the development of non-invasive procedures to assess phonatory and respiratory dynamics. These procedures, when used as an adjunct to laryngoscopy, can provide information that is useful in the diagnosis and management of vocal tract dysfunction. The Laryngograph and Computer-Aided Fluency Establishment Trainer, described here, are examples of this new technology.

  8. [Non-invasive brain stimulation for Parkinson's disease].

    PubMed

    Gajo, Gianandrea; Pollak, Pierre; Lüscher, Christian; Benninger, David

    2015-04-29

    Parkinson's disease (PD) is a major socio-economic burden increasing with the aging population. In advanced PD, the emergence of symptoms refractory to conventional therapy poses a therapeutic challenge. The success of deep brain stimulation (DBS) and advances in the understanding of the pathophysiology of PD have raised interest in non-invasive brain stimulation (NIBS) as an alternative therapeutic tool. NIBS could offer an alternative approach for patients at risk who are excluded from surgery and/or to treat refractory symptoms. The treatment of the freezing of gait, a major cause of disability and falls in PD patients, could be enhanced by transcranial direct current stimulation (tDCS). A therapeutic study is currently performed at the Department of Neurology at the CHUV.

  9. Physician liability and non-invasive prenatal testing.

    PubMed

    Toews, Maeghan; Caulfield, Timothy

    2014-10-01

    Although non-invasive prenatal testing (NIPT) marks a notable development in the field of prenatal genetic testing, there are some physician liability considerations raised by this technology. As NIPT is still emerging as the standard of care and is just starting to receive provincial funding, the question arises of whether physicians are obligated to disclose the availability of NIPT to eligible patients as part of the physician-patient discussion about prenatal screening and diagnosis. If NIPT is discussed with patients, it is important to disclose the limitations of this technology with respect to its accuracy and the number of disorders that it can detect when compared with invasive diagnostic options. A failure to sufficiently disclose these limitations could leave patients with false assurances about the health of their fetuses and could raise informed consent and liability issues, particularly if a child is born with a disability as a result.

  10. Non-invasive neuroimaging using near-infrared light

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Boas, David A.; Sutton, Jeffrey P.

    2002-01-01

    This article reviews diffuse optical brain imaging, a technique that employs near-infrared light to non-invasively probe the brain for changes in parameters relating to brain function. We describe the general methodology, including types of measurements and instrumentation (including the tradeoffs inherent in the various instrument components), and the basic theory required to interpret the recorded data. A brief review of diffuse optical applications is included, with an emphasis on research that has been done with psychiatric populations. Finally, we discuss some practical issues and limitations that are relevant when conducting diffuse optical experiments. We find that, while diffuse optics can provide substantial advantages to the psychiatric researcher relative to the alternative brain imaging methods, the method remains substantially underutilized in this field.

  11. Non-Invasive Brain Stimulation in Neglect Rehabilitation: An Update

    PubMed Central

    Müri, René Martin; Cazzoli, Dario; Nef, Tobias; Mosimann, Urs P.; Hopfner, Simone; Nyffeler, Thomas

    2013-01-01

    Here, we review the effects of non-invasive brain stimulation such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies) fulfilling our search criteria. Activity of daily living measures such as the Barthel Index or, more specifically for neglect, the Catherine Bergego Scale were the outcome measure in three studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence. The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta-burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients. PMID:23772209

  12. Non-invasive pressure measuring device and method

    NASA Astrophysics Data System (ADS)

    Welch, Jeanne A.

    1990-12-01

    The invention relates generally to measuring devices and to devices for measuring the pressure in a sealed container. More particularly, the invention relates to a non-invasive device and method for measuring the pressure of a gas in a double-envelope lamp. An infrared gaseous discharge lamp of integrated double-envelope construction has an inner chamber or envelope filled with a gaseous medium under relatively high pressure which provides illumination when the lamp is energized. The outer chamber or envelope is normally evacuated or otherwise provided with a relatively low-pressure gas. Double-envelope lamps are subject to gas leaks from the inner chamber to the outer chamber. Eventually, these leaks may lead to catastrophic lamp failure by a mechanism that involves electric arcing in the outer chamber.

  13. Non-invasive prenatal testing: ethics and policy considerations.

    PubMed

    Vanstone, Meredith; King, Carol; de Vrijer, Barbra; Nisker, Jeff

    2014-06-01

    New technologies analyzing fetal DNA in maternal blood have led to the wide commercial availability of non-invasive prenatal testing (NIPT). We present here for clinicians the ethical and policy issues related to an emerging practice option. Although NIPT presents opportunities for pregnant women, particularly women who are at increased risk of having a baby with an abnormality or who are otherwise likely to access invasive prenatal testing, NIPT brings significant ethics and policy challenges. The ethical issues include multiple aspects of informed decision-making, such as access to counselling about the possible results of the test in advance of making a decision about participation in NIPT. Policy considerations include issues related to offering and promoting a privately available medical strategy in publicly funded institutions. Ethics and policy considerations merge in NIPT with regard to sex selection and support for persons living with disabilities.

  14. Non invasive sensing technologies for cultural heritage management and fruition

    NASA Astrophysics Data System (ADS)

    Soldovieri, Francesco; Masini, Nicola

    2016-04-01

    The relevance of the information produced by science and technology for the knowledge of the cultural heritage depends on the quality of the feedback and, consequently, on the "cultural" distance between scientists and end-users. In particular, the solution to this problem mainly resides in the capability of end-users' capability to assess and transform the knowledge produced by diagnostics with regard to: information on both cultural objects and sites (decay patterns, vulnerability, presence of buried archaeological remains); decision making (management plan, conservation project, and excavation plan). From our experience in the field of the cultural heritage and namely the conservation, of monuments, there is a significant gap of information between technologists (geophysicists/physicists/engineers) and end-users (conservators/historians/architects). This cultural gap is due to the difficulty to interpret "indirect data" produced by non invasive diagnostics (i.e. radargrams/thermal images/seismic tomography etc..) in order to provide information useful to improve the historical knowledge (e.g. the chronology of the different phases of a building), to characterise the state of conservation (e.g. detection of cracks in the masonry) and to monitor in time cultural heritage artifacts and sites. The possible answer to this difficulty is in the set-up of a knowledge chain regarding the following steps: - Integrated application of novel and robust data processing methods; - Augmented reality as a tool for making easier the interpretation of non invasive - investigations for the analysis of decay pathologies of masonry and architectural surfaces; - The comparison between direct data (carrots, visual inspection) and results from non-invasive tests, including geophysics, aims to improve the interpretation and the rendering of the monuments and even of the archaeological landscapes; - The use of specimens or test beds for the detection of archaeological features and

  15. Moral Enhancement Using Non-invasive Brain Stimulation.

    PubMed

    Darby, R Ryan; Pascual-Leone, Alvaro

    2017-01-01

    Biomedical enhancement refers to the use of biomedical interventions to improve capacities beyond normal, rather than to treat deficiencies due to diseases. Enhancement can target physical or cognitive capacities, but also complex human behaviors such as morality. However, the complexity of normal moral behavior makes it unlikely that morality is a single capacity that can be deficient or enhanced. Instead, our central hypothesis will be that moral behavior results from multiple, interacting cognitive-affective networks in the brain. First, we will test this hypothesis by reviewing evidence for modulation of moral behavior using non-invasive brain stimulation. Next, we will discuss how this evidence affects ethical issues related to the use of moral enhancement. We end with the conclusion that while brain stimulation has the potential to alter moral behavior, such alteration is unlikely to improve moral behavior in all situations, and may even lead to less morally desirable behavior in some instances.

  16. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    NASA Astrophysics Data System (ADS)

    Antonacci, Giuseppe; Braakman, Sietse

    2016-11-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p < 0.0001) and the surrounding cytoplasm (p < 0.0001). Moreover, we demonstrate the mechanical response of cells to Latrunculin-A, a drug that reduces cell stiffness by preventing cytoskeletal assembly. Our technique can therefore generate valuable insights into cellular biomechanics and its role in pathophysiology.

  17. [Non-invasive prenatal testing: challenges for future implementation].

    PubMed

    Henneman, Lidewij; Page-Chrisiaens, G C M L Lieve; Oepkes, Dick

    2015-01-01

    The non-invasive prenatal test (NIPT) is an accurate and safe test in which blood from the pregnant woman is used to investigate if the unborn child possibly has trisomy 21 (Down's syndrome), trisomy 18 (Edwards' syndrome) or trisomy 13 (Patau syndrome). Since April 2014 the NIPT has been available in the Netherlands as part of the TRIDENT implementation project for those in whom the first trimester combined test showed an elevated risk (> 1:200) of trisomy, or on medical indication, as an alternative to chorionic villous sampling or amniocentesis. Since the introduction of the NIPT the use of these invasive tests, which are associated with a risk of miscarriage, has fallen steeply. The NIPT may replace the combined test. Also the number of conditions that is tested for can be increased. Modification of current prenatal screening will require extensive discussion, but whatever the modification, careful counseling remains essential to facilitate pregnant women's autonomous reproductive decision making.

  18. Ultrahigh-speed non-invasive widefield angiography

    NASA Astrophysics Data System (ADS)

    Blatter, Cedric; Klein, Thomas; Grajciar, Branislav; Schmoll, Tilman; Wieser, Wolfgang; Andre, Raphael; Huber, Robert; Leitgeb, Rainer A.

    2012-07-01

    Retinal and choroidal vascular imaging is an important diagnostic benefit for ocular diseases such as age-related macular degeneration. The current gold standard for vessel visualization is fluorescence angiography. We present a potential non-invasive alternative to image blood vessels based on functional Fourier domain optical coherence tomography (OCT). For OCT to compete with the field of view and resolution of angiography while maintaining motion artifacts to a minimum, ultrahigh-speed imaging has to be introduced. We employ Fourier domain mode locking swept source technology that offers high quality imaging at an A-scan rate of up to 1.68 MHz. We present retinal angiogram over ˜48 deg acquired in a few seconds in a single recording without the need of image stitching. OCT at 1060 nm allows for high penetration in the choroid and efficient separate characterization of the retinal and choroidal vascularization.

  19. Novel non invasive diagnostic strategies in bladder cancer

    PubMed Central

    TRUTA, ANAMARIA; POPON, TUDOR ADRIAN HODOR; SARACI, GEORGE; GHERVAN, LIVIU; POP, IOAN VICTOR

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, −145, −222, −210, −10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population. PMID:27152066

  20. Novel non invasive diagnostic strategies in bladder cancer.

    PubMed

    Truta, Anamaria; Popon, Tudor Adrian Hodor; Saraci, George; Ghervan, Liviu; Pop, Ioan Victor

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, -145, -222, -210, -10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population.

  1. Skin autofluorescence, a non-invasive marker of advanced glycation end products: clinical relevance and limitations.

    PubMed

    Da Moura Semedo, Cidila; Webb, M'Balu; Waller, Helen; Khunti, Kamlesh; Davies, Melanie

    2017-01-31

    Advanced glycation end products (AGEs) are protein-bound compounds derived from glycaemic and oxidative stress that contain fluorescent properties, which can be non-invasively measured as skin autofluorescence (SAF) by the AGE Reader. SAF has been demonstrated to be a biomarker of cumulative skin AGEs and potentially may be a better predictor for the development of chronic complications and mortality in diabetes than glycated haemoglobin A1c. However, there are several confounding factors that should be assessed prior to its broader application: these include presence of other fluorescent compounds in the skin that might be measured (eg, fluorophores), skin pigmentation and use of skin creams. The aim of this article is to provide a theoretical background of this newly developed method, evaluate its clinical relevance and discuss the potential confounding factors that need further analysis.

  2. Non-invasive flux measurements using microsensors: theory, limitations, and systems.

    PubMed

    Newman, Ian; Chen, Shao-Liang; Porterfield, D Marshall; Sun, Jian

    2012-01-01

    Knowledge of the fluxes of ions and neutral molecules across the outer membrane or boundary of living tissues and cells is an important strand of applied molecular biology. Such fluxes can be measured non-invasively with good resolution in time and space. Two systems (MIFE™ and SIET) have been developed and have become widely used to implement this technique, and they are commercially available. This Chapter is the first comparative description of these two systems. It gives the context, the basic underlying theory, practical limitations inherent in the technique, theoretical developments, guidance on the practicalities of the technique, and the functionality of the two systems. Although the technique is strongly relevant to plant salt tolerance and other plant stresses (drought, temperature, pollutants, waterlogging), it also has rich relevance throughout biomedical studies and the molecular genetics of transport proteins.

  3. Targeted Deletion of MicroRNA-22 Promotes Stress-Induced Cardiac Dilation and Contractile Dysfunction

    PubMed Central

    Gurha, Priyatansh; Abreu-Goodger, Cei; Wang, Tiannan; Ramirez, Maricela O.; Drumond, Ana L.; van Dongen, Stijn; Chen, Yuqing; Bartonicek, Nenad; Enright, Anton J.; Lee, Brendan; Kelm, Robert J.; Reddy, Anilkumar K.; Taffet, George E.; Bradley, Allan; Wehrens, Xander H.; Entman, Mark L.; Rodriguez, Antony

    2012-01-01

    Background Delineating the role of microRNAs (miRNAs) in the posttranscriptional gene regulation offers new insights into how the heart adapts to pathological stress. We developed a knockout of miR-22 in mice and investigated its function in the heart. Methods and Results Here, we show that miR-22–deficient mice are impaired in inotropic and lusitropic response to acute stress by dobutamine. Furthermore, the absence of miR-22 sensitized mice to cardiac decompensation and left ventricular dilation after long-term stimulation by pressure overload. Calcium transient analysis revealed reduced sarcoplasmic reticulum Ca2+ load in association with repressed sarcoplasmic reticulum Ca2+ ATPase activity in mutant myocytes. Genetic ablation of miR-22 also led to a decrease in cardiac expression levels for Serca2a and muscle-restricted genes encoding proteins in the vicinity of the cardiac Z disk/titin cytoskeleton. These phenotypes were attributed in part to inappropriate repression of serum response factor activity in stressed hearts. Global analysis revealed increased expression of the transcriptional/translational repressor purine-rich element binding protein B, a highly conserved miR-22 target implicated in the negative control of muscle expression. Conclusion These data indicate that miR-22 functions as an integrator of Ca2+ homeostasis and myofibrillar protein content during stress in the heart and shed light on the mechanisms that enhance propensity toward heart failure. PMID:22570371

  4. Prognostic value of normal adenosine-stress cardiac magnetic resonance imaging.

    PubMed

    Pilz, Guenter; Jeske, Andrea; Klos, Markus; Ali, Eman; Hoefling, Berthold; Scheck, Roland; Bernhardt, Peter

    2008-05-15

    We investigated the prognostic value of normal adenosine stress cardiac magnetic resonance (CMR) in suspected coronary artery disease (CAD). Prospectively enrolled in the study were 218 patients with suspected CAD, no stress hypoperfusion, and no delayed enhancement in CMR, and consecutively deferred coronary angiography. The primary end point was a 12-month rate of major adverse cardiac events (MACE; cardiovascular mortality, myocardial infarction, revascularization, hospitalization due to cardiovascular event). CMR indication was symptomatic angina (Canadian Cardiovascular Society II in 42% and III in 7%) or evaluation of myocardial ischemia in patients with arrhythmia, syncope, and/or equivocal stress tests and cardiovascular risk factors (51%). As the main result, the 12-month MACE rate was 2/218 (1 stent implantation, 1 bypass surgery) and CMR negative predictive value 99.1%. There was no cardiac death or myocardial infarction. In conclusion, normal adenosine stress CMR predicts a very low MACE rate and an excellent 1-year prognosis in patients with suspected CAD. Our results provide clinical reassurance that patients at risk for CAD-associated MACE were not missed by CMR. Hence, CMR may serve as a reliable noninvasive gatekeeper to reduce the number of redundant coronary angiographies.

  5. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, Michael P.

    1996-01-01

    A coaxial hyperthermia applicator for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator.

  6. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

    DOEpatents

    Ross, M.P.

    1996-08-27

    A coaxial hyperthermia applicator is disclosed for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator. 11 figs.

  7. Non-invasive Optical Molecular Imaging for Cancer Detection

    NASA Astrophysics Data System (ADS)

    Luo, Zhen

    Cancer is a leading cause of death worldwide. It remains the second most common cause of death in the US, accounting for nearly 1 out of every 4 deaths. Improved fundamental understanding of molecular processes and pathways resulting in cancer development has catalyzed a shift towards molecular analysis of cancer using imaging technologies. It is expected that the non-invasive or minimally invasive molecular imaging analysis of cancer can significantly aid in improving the early detection of cancer and will result in reduced mortality and morbidity associated with the disease. The central hypothesis of the proposed research is that non-invasive imaging of changes in metabolic activity of individual cells, and extracellular pH within a tissue will improve early stage detection of cancer. The specific goals of this research project were to: (a) develop novel optical imaging probes to image changes in choline metabolism and tissue pH as a function of progression of cancer using clinically isolated tissue biopsies; (b) correlate changes in tissue extracellular pH and metabolic activity of tissues as a function of disease state using clinically isolated tissue biopsies; (c) provide fundamental understanding of relationship between tumor hypoxia, acidification of the extracellular space and altered cellular metabolism with progression of cancer. Three novel molecular imaging probes were developed to detect changes in choline and glucose metabolism and extracellular pH in model systems and clinically isolated cells and biopsies. Glucose uptake and metabolism was measured using a fluorescence analog of glucose, 2-NBDG (2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose), while choline metabolism was measured using a click chemistry analog of choline, propargyl choline, which can be in-situ labeled with a fluorophore Alexa-488 azide via a click chemistry reaction. Extracellular pH in tissue were measured by Alexa-647 labeled pHLIP (pH low insertion peptide

  8. Tissue Damage Characterization Using Non-invasive Optical Modalities

    NASA Astrophysics Data System (ADS)

    Diaz, David

    The ability to determine the degree of cutaneous and subcutaneous tissue damage is essential for proper wound assessment and a significant factor for determining patient treatment and morbidity. Accurate characterization of tissue damage is critical for a number of medical applications including surgical removal of nonviable tissue, severity assessment of subcutaneous ulcers, and depth assessment of visually open wounds. The main objective of this research was to develop a non-invasive method for identifying the extent of tissue damage underneath intact skin that is not apparent upon visual examination. This work investigated the relationship between tissue optical properties, blood flow, and tissue viability by testing the hypotheses that (a) changes in tissue oxygenation and/or microcirculatory blood flow measurable by Diffuse Near Infrared Spectroscopy (DNIRS) and Diffuse Correlation Spectroscopy (DCS) differ between healthy and damaged tissue and (b) the magnitude of those changes differs for different degrees of tissue damage. This was accomplished by developing and validating a procedure for measuring microcirculatory blood flow and tissue oxygenation dynamics at multiple depths (up to 1 centimeter) using non-invasive DCS and DNIRS technologies. Due to the lack of pressure ulcer animal models that are compatible with our optical systems, a proof of concept was conducted in a porcine burn model prior to conducting clinical trials in order to assess the efficacy of the system in-vivo. A reduction in total hemoglobin was observed for superficial (5%) and deep burns (35%) along with a statistically significant difference between the optical properties of superficial and deep burns (p < 0.05). Burn depth and viable vessel density were estimated via histological samples. 42% of vessels in the dermal layer were viable for superficial burns, compared to 25% for deep burns. The differences detected in optical properties and hemoglobin content by optical measurements

  9. Effects of far infrared rays irradiated from ceramic material (BIOCERAMIC) on psychological stress-conditioned elevated heart rate, blood pressure, and oxidative stress-suppressed cardiac contractility.

    PubMed

    Leung, Ting-Kai; Chen, Chien-Ho; Tsai, Shih-Ying; Hsiao, George; Lee, Chi-Ming

    2012-10-31

    The present study examined the effects of BIOCERAMIC on psychological stress-conditioned elevated heart rate, blood pressure and oxidative stress-suppressed cardiac contractility using in vivo and in vitro animal models. We investigated the effects of BIOCERAMIC on the in vivo cardiovascular hemodynamic parameters of rats by monitoring their heart rates, systolic blood pressure, mean blood pressure and diastolic blood pressure. Thereafter, we assayed its effects on the heart rate in an isolated frog heart with and without adrenaline stimulation, and on cardiac contractility under oxidative stress. BIOCERAMIC caused significant decreases in heart rates and systolic and mean blood pressure in the stress-conditioned heart rate rat models (P < 0.05), as well as in the experimental models of an isolated frog heart with and without adrenaline stimulation (P < 0.05), and normalized cardiac contractility under oxidative stress (P < 0.05). BIOCERAMIC may, therefore, normalize the effects of psychological stress and oxidative stress conditions.

  10. Impact of weightlessness on cardiac shape and left ventricular stress/strain distributions.

    PubMed

    Iskovitz, Ilana; Kassemi, Mohammad; Thomas, James D

    2013-12-01

    In this paper, a finite element model of the heart is developed to investigate the impact of different gravitational loadings of Earth, Mars, Moon, and microgravity on the cardiac shape and strain/stress distributions in the left ventricle. The finite element model is based on realistic 3D heart geometry, detailed fiber/sheet micro-architecture, and a validated orthotropic cardiac tissue model and constitutive relationship that capture the passive behavior of the heart at end-diastole. The model predicts the trend and magnitude of cardiac shape change at different gravitational levels with great fidelity in comparison to recent cardiac sphericity measurements performed during simulated reduced-gravity parabolic flight experiments. Moreover, the numerical predictions indicate that although the left ventricular strain distributions remain relatively unaltered across the gravitational fields and the strain extrema values occur at the same relative locations, their values change noticeably with decreasing gravity. As for the stress, however, both the magnitude and location of the extrema change with a decrease in the gravitational field. Consequently, tension regions of the heart on Earth can change into compression regions in space.

  11. Non-invasive photo acoustic approach for human bone diagnosis.

    PubMed

    Thella, Ashok Kumar; Rizkalla, James; Helmy, Ahdy; Suryadevara, Vinay Kumar; Salama, Paul; Rizkalla, Maher

    2016-12-01

    The existing modalities of bone diagnosis including X-ray and ultrasound may cite drawback in some cases related to health issues and penetration depth, while the ultrasound modality may lack image quality. Photo acoustic approach however, provides light energy to the acoustic wave, enabling it to activate and respond according to the propagating media (which is type of bones in this case). At the same time, a differential temperature change may result in the bio heat response, resulting from the heat absorbed across the multiple materials under study. In this work, we have demonstrated the features of using photo acoustic modality in order to non-invasively diagnose the type of human bones based on their electrical, thermal, and acoustic properties that differentiate the output response of each type. COMSOL software was utilized to combine both acoustic equations and bio heat equations, in order to study both the thermal and acoustic responses through which the differential diagnosis can be obtained. In this study, we solved both the acoustic equation and bio heat equations for four types of bones, bone (cancellous), bone (cortical), bone marrow (red), and bone marrow (yellow). 1 MHz acoustic source frequency was chosen and 10(5) W/m(2) power source was used in the simulation. The simulation tested the dynamic response of the wave over a distance of 5 cm from each side for the source. Near 2.4 cm was detected from simulation from each side of the source with a temperature change of within 0.5 K for various types of bones, citing a promising technique for a practical model to detect the type of bones via the differential temperature as well as the acoustic was response via the multiple materials associated with the human bones (skin and blood). The simulation results suggest that the PA technique may be applied to non-invasive diagnosis for the different types of bones, including cancerous bones. A practical model for detecting both the temperature change via

  12. N-acetylcysteine reverses cardiac myocyte dysfunction in a rodent model of behavioral stress

    PubMed Central

    Chen, Fangping; Hadfield, Jessalyn M.; Berzingi, Chalak; Hollander, John M.; Miller, Diane B.; Nichols, Cody E.

    2013-01-01

    Compelling clinical reports reveal that behavioral stress alone is sufficient to cause reversible myocardial dysfunction in selected individuals. We developed a rodent stress cardiomyopathy model by a combination of prenatal and postnatal behavioral stresses (Stress). We previously reported a decrease in percent fractional shortening by echo, both systolic and diastolic dysfunction by catheter-based hemodynamics, as well as attenuated hemodynamic and inotropic responses to the β-adrenergic agonist, isoproterenol (ISO) in Stress rats compared with matched controls (Kan H, Birkle D, Jain AC, Failinger C, Xie S, Finkel MS. J Appl Physiol 98: 77–82, 2005). We now report enhanced catecholamine responses to behavioral stress, as evidenced by increased circulating plasma levels of norepinephrine (P < 0.01) and epinephrine (P < 0.01) in Stress rats vs. controls. Cardiac myocytes isolated from Stress rats also reveal evidence of oxidative stress, as indicated by decreased ATP, increased GSSG, and decreased GSH-to-GSSG ratio in the presence of increased GSH peroxidase and catalase activities (P < 0.01, for each). We also report blunted inotropic and intracellular Ca2+ concentration responses to extracellular Ca2+ (P < 0.05), as well as altered inotropic responses to the intracellular calcium regulator, caffeine (20 mM; P < 0.01). Treatment of cardiac myocytes with N-acetylcysteine (NAC) (10−3 M) normalized calcium handling in response to ISO and extracellular Ca2+ concentration and inotropic response to caffeine (P < 0.01, for each). NAC also attenuated the blunted inotropic response to ISO and Ca2+ (P < 0.01, for each). Surprisingly, NAC did not reverse the changes in GSH, GSSG, or GSH-to-GSSG ratio. These data support a GSH-independent salutary effect of NAC on intracellular calcium signaling in this rodent model of stress-induced cardiomyopathy. PMID:23722706

  13. Evaluation of ventricular wall stress and cardiac function in patients with dilated cardiomyopathy.

    PubMed

    Scardulla, Francesco; Rinaudo, Antonino; Pasta, Salvatore; Scardulla, Cesare

    2016-01-01

    Dilated cardiomyopathy is a heart disease characterized by both left ventricular dilatation and left ventricular systolic dysfunction, leading to cardiac remodeling and ultimately heart failure. We aimed to investigate the effect of dilated cardiomyopathy on the pump performance and myocardial wall mechanics using patient-specific finite element analysis. Results evinced pronounced end-systolic wall stress on left ventricular wall of patients with dilated cardiomyopathy as compared to that of normal hearts. In dilated cardiomyopathy, both end-diastolic and end-systolic pressure-volume relationships of left ventricle and right ventricle were shifted to the right compared to controls, suggesting reduced myocardial contractility. We hereby propose that finite element analysis represents a useful tool to assess the myocardial wall stress and cardiac work, which are responsible for progressive left ventricular deterioration and poor clinical course.

  14. Aerobic exercise training rescues cardiac protein quality control and blunts endoplasmic reticulum stress in heart failure rats.

    PubMed

    Bozi, Luiz H M; Jannig, Paulo R; Rolim, Natale; Voltarelli, Vanessa A; Dourado, Paulo M M; Wisløff, Ulrik; Brum, Patricia C

    2016-11-01

    Cardiac endoplasmic reticulum (ER) stress through accumulation of misfolded proteins plays a pivotal role in cardiovascular diseases. In an attempt to reestablish ER homoeostasis, the unfolded protein response (UPR) is activated. However, if ER stress persists, sustained UPR activation leads to apoptosis. There is no available therapy for ER stress relief. Considering that aerobic exercise training (AET) attenuates oxidative stress, mitochondrial dysfunction and calcium imbalance, it may be a potential strategy to reestablish cardiac ER homoeostasis. We test the hypothesis that AET would attenuate impaired cardiac ER stress after myocardial infarction (MI). Wistar rats underwent to either MI or sham surgeries. Four weeks later, rats underwent to 8 weeks of moderate-intensity AET. Myocardial infarction rats displayed cardiac dysfunction and lung oedema, suggesting heart failure. Cardiac dysfunction in MI rats was paralleled by increased protein levels of UPR markers (GRP78, DERLIN-1 and CHOP), accumulation of misfolded and polyubiquitinated proteins, and reduced chymotrypsin-like proteasome activity. These results suggest an impaired cardiac protein quality control. Aerobic exercise training improved exercise capacity and cardiac function of MI animals. Interestingly, AET blunted MI-induced ER stress by reducing protein levels of UPR markers, and accumulation of both misfolded and polyubiquinated proteins, which was associated with restored proteasome activity. Taken together, our study provide evidence for AET attenuation of ER stress through the reestablishment of cardiac protein quality control, which contributes to better cardiac function in post-MI heart failure rats. These results reinforce the importance of AET as primary non-pharmacological therapy to cardiovascular disease.

  15. Non invasive analysis of miniature paintings: Proposal for an analytical protocol

    NASA Astrophysics Data System (ADS)

    Aceto, Maurizio; Agostino, Angelo; Fenoglio, Gaia; Gulmini, Monica; Bianco, Valentina; Pellizzi, Eleonora

    2012-06-01

    The characterisation of palettes used in manuscript illumination is a hard analytical task, due to value and fragility of the analysed items. Analysis on miniatures must be necessarily non-invasive and fast and requires the use of several techniques since no single technique is able to provide all information needed. In this work a four-step analytical protocol is proposed for non-invasive in situ characterisation of miniature paintings. The protocol allows the identification of coloured materials through the use in sequence of complementary techniques, so as to fully exploit the information given by each instrument. Preliminarily to the instrumental investigations on ancient books and miniatures is the compilation of spectroscopic databases obtained from "standard" samples prepared on parchment, according to recipes described in medieval artistic treatises. The protocol starts with an extensive investigation with UV-visible spectrophotometry in reflectance mode, collecting spectra from all the most significant painted areas in the manuscript; chemometric classification is then performed on the spectra to highlight areas possibly containing the same materials. The second step involves in-depth inspection of miniatures under optical microscopy that guides the interpretation of reflectance spectra. XRF spectrometry is then performed to characterise pigments and metal layers, to verify the presence of overlapping layers, to identify mordants in lakes and to recognise minor components that may yield information concerning provenance; in addition, chemometric classification can be performed on element concentrations to highlight similar areas. Finally, Raman spectroscopy is used to shed light on the uncertain cases, if still present. Such a procedure offers a wealth of information without causing stress to the manuscripts under analysis.

  16. An optical approach for non-invasive blood clot testing

    NASA Astrophysics Data System (ADS)

    Kalchenko, Vyacheslav; Brill, Alexander; Fine, Ilya; Harmelin, Alon

    2007-02-01

    Physiological blood coagulation is an essential biological process. Current tests for plasma coagulation (clotting) need to be performed ex vivo and require fresh blood sampling for every test. A recently published work describes a new, noninvasive, in vivo approach to assess blood coagulation status during mechanical occlusion1. For this purpose, we have tested this approach and applied a controlled laser beam to blood micro-vessels of the mouse ear during mechanical occlusion. Standard setup for intravital transillumination videomicroscopy and laser based imaging techniques were used for monitoring the blood clotting process. Temporal mechanical occlusion of blood vessels in the observed area was applied to ensure blood flow cessation. Subsequently, laser irradiation was used to induce vascular micro-injury. Changes in the vessel wall, as well as in the pattern of blood flow, predispose the area to vascular thrombosis, according to the paradigm of Virchow's triad. In our experiments, two elements of Virchow's triad were used to induce the process of clotting in vivo, and to assess it optically. We identified several parameters that can serve as markers of the blood clotting process in vivo. These include changes in light absorption in the area of illumination, as well as changes in the pattern of the red blood cells' micro-movement in the vessels where blood flow is completely arrested. Thus, our results indicate that blood coagulation status can be characterized by non-invasive, in vivo methodologies.

  17. Non-invasive administration of biodegradable nano-carrier vaccines

    PubMed Central

    Kalam, Mohd Abul; Khan, Abdul Arif; Alshamsan, Aws

    2017-01-01

    Polymeric nanoparticulate carriers play an important role and holding a significant potential for the development of novel immunomodulatory agents as easily they are taken up by antigen presenting cells. They allow an enhanced antigen stability, better immunogenicity and immunostimulatory effect with sustained and controlled release of the antigen to the target sites. Better information and vital understanding of mechanism of action, interaction of such vectors with the APCs and dendritic cells and antigen release kinetics in immunomodulatory effects, and improved knowledge of their in vivo fate and distribution are now needed, those collectively would speed up the rational strategies of nanoparticles as carriers for vaccines and other protein antigens. The evolution of such innovative adjuvants for protein and DNA immunizations are an exciting and growing zone in immunology, which may enhance the clinical outcomes in many infectious and non-infectious diseases. This review summarizes the recent advances in nano-vaccinology with polymeric (especially biodegradable) carriers, their methods of preparation, surface modification, their interaction with antigen presenting cells, release of antigens, its kinetics and mechanism in the delivery of vaccines via non-invasive routes. PMID:28123631

  18. Non-invasive ventilation in amyotrophic lateral sclerosis.

    PubMed

    Vrijsen, Bart; Testelmans, Dries; Belge, Catharina; Robberecht, Wim; Van Damme, Philip; Buyse, Bertien

    2013-03-01

    Abstract Non-invasive ventilation (NIV) is widely used to improve alveolar hypoventilation in amyotrophic lateral sclerosis. Several studies indicate a better survival when NIV is used, certainly in patients with none to moderate bulbar dysfunction. Data on quality of life (QoL) are rather disputable. Overall QoL is shown to be equivalent in patients with or without NIV, although health-related QoL is shown to be increased in patients with none to moderate bulbar dysfunction. NIV improves sleep quality, although patient-ventilator asynchronies are demonstrated. FVC < 50%, seated or supine, has been widely applied as threshold to initiate NIV. Today, measurements of respiratory muscle strength, nocturnal gas exchange and symptomatic complaints are used as indicators to start NIV. Being compliant with NIV therapy increases QoL and survival. Cough augmentation has an important role in appropriate NIV. Patients have today more technical options and patients with benefit from these advances are growing in number. Tracheal ventilation needs to be discussed when NIV seems impossible or becomes insufficient.

  19. Non invasive tools for the diagnosis of liver cirrhosis

    PubMed Central

    Soresi, Maurizio; Giannitrapani, Lydia; Cervello, Melchiorre; Licata, Anna; Montalto, Giuseppe

    2014-01-01

    Liver cirrhosis (LC), the end stage of many forms of chronic hepatitis of different etiologies is a diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules surrounded by annular fibrosis. This chronic progressive clinical condition, leads to liver cell failure and portal hypertension, which can favour the onset of hepatocellular carcinoma. Defining the phase of the natural history is crucial for therapeutic choice and prognosis. Liver biopsy is currently considered the best available standard of reference but it has some limits, so alternative tools have been developed to substitute liver biopsy when assessing liver fibrosis. Serum markers offer a cost-effective alternative to liver biopsy being less invasive and theoretically without complications. They can be classified into direct and indirect markers which may be used alone or in combination to produce composite scores. Diagnostic imaging includes a number of instruments and techniques to estimate liver fibrosis and cirrhosis like ultrasound (US), US Doppler, contrast enhanced US and Elastography. US could be used for the diagnosis of advanced LC while is not able to evaluate progression of fibrosis, in this case Elastography is more reliable. This review aims to revise the most recent data from the literature about non invasive methods useful in defining liver fibrosis. PMID:25561782

  20. Mucositis and non-invasive markers of small intestinal function.

    PubMed

    Tooley, Katie L; Howarth, Gordon S; Butler, Ross N

    2009-05-01

    Mucositis is a common and debilitating side effect of chemotherapy that manifests due to the inability of chemotherapy agents to discriminate between normal and neoplastic cells. This results in ulcerating lesions lining the gastrointestinal tract. Moreover, the development of efficacious treatments for small intestinal mucositis has been hindered as the pathobiology of mucositis is still not fully understood. The small intestine is an extensive organ which is largely inaccessible by conventional means. Non-invasive biomarkers such as small intestinal permeability, H(2) breath tests, serum citrulline tests and the (13)C-sucrose breath test (SBT) have emerged as potential markers of small intestinal function. The SBT is emerging as the more appropriate biomarker to assess chemotherapy-induced mucositis in cancer patients and animal models, where it measures the decrease in sucrase activity associated with villus blunting and crypt disruption. The SBT has been successfully applied to detect mucositis induced by different classes of chemotherapy agents and has been used successfully to monitor small intestinal function with a range of candidate anti-mucositis treatments. We propose the SBT a superior biomarker of small intestinal function that could be successfully applied in clinical practice for monitoring the development of mucositis in cancer patients undergoing chemotherapy.

  1. Alteration of Political Belief by Non-invasive Brain Stimulation.

    PubMed

    Chawke, Caroline; Kanai, Ryota

    2015-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to.

  2. Non-invasive diagnosis of mitral regurgitation by Doppler echocardiography.

    PubMed Central

    Blanchard, D; Diebold, B; Peronneau, P; Foult, J M; Nee, M; Guermonprez, J L; Maurice, P

    1981-01-01

    The value of Doppler echocardiography for the non-invasive diagnosis of mitral regurgitation was studied blindly in 161 consecutive invasively investigated adult patients. Regurgitation was graded from 0 to 3 at selective left ventricular angiography. The Doppler echocardiographic examination was considered to be positive when a disturbed systolic flow was found within the left atrium behind the aorta or the anterior leaflet of the mitral valve. The test was considered to be negative in the absence of a regurgitant jet. The level of the signal to noise ratio was checked by the recording of the ventricular filling flow. The study was performed in 131 cases from the left side of the sternum and in 101 cases from the apex. There were no false positives and thus the specificity was 100 per cent. The 20 false negatives were all in patients with grade 1 regurgitation. Thus only some (33%) instances of mild regurgitation were misdiagnosed, and the sensitivity for moderate to severe mitral regurgitation was 100 per cent. PMID:7236465

  3. Non-invasive biosensor and wilreless interrogating system for hypoglycemia

    NASA Astrophysics Data System (ADS)

    Varadan, Vijay K.; Whitchurch, Ashwin K.; Saukesi, K.

    2002-11-01

    Hypoglycemia - abnormal decrease in blood sugar - is a major obstacle in the management of diabetes and prevention of long-term complications, and it may impose serious effects on the brain, including impairment of memory and other cognitive functions. This paper presents the development of a non-invasive sensor with miniaturized telemetry device in a wrist-watch for monitoring glucose concentration in blood. The sensor concept is based on optical chiralit of glucose level in the interstitial fluid. The wrist watch consists of a laser power source of the wavelength compatible with the glucose. A nanofilm with specific chirality is placed at the bottom of the watch. The light then passes through the film and illuminates a small area on the skin.It has been documented that there is certain concentration of sugar level is taken by the intertitial fluid from the blood stream and deposit a portion of it at the dead skin. The wrist-watch when in contact with the outer skin of the human will thus monitor the glucose concentration. A wireless monitoring system in the watch then downloads the data from the watch to a Palm or laptop computer.

  4. Non-invasive methods in paediatric exercise physiology.

    PubMed

    Armstrong, Neil; Fawkner, Samantha G

    2008-04-01

    Oded Bar-Or's hypothesis that children may be "metabolic non-specialists", even when engaging in specialized sports, has stimulated the study of paediatric exercise metabolism since the publication of his classic text Pediatric sports medicine for the practitioner in 1983. Evidence drawn from several methodologies indicates an interplay of anaerobic and aerobic exercise metabolism in which children have a relatively higher metabolic contribution from oxidative energy pathways than adolescents or adults, whereas there is a progressive increase in glycolytic support of exercise with age, at least into adolescence and possibly into young adulthood. The picture is generally consistent but incomplete, as research with young people has been limited by both ethical and methodological constraints. The recent rigorous introduction of non-invasive techniques such as breath-by-breath respiratory gas analysis and magnetic resonance spectroscopy into paediatric exercise physiology promises to open up new avenues of research and generate unique insights into the metabolism of the exercising muscle during growth and maturation. It therefore appears that we might have available the tools necessary to answer some of the elegant questions raised by Professor Bar-Or over 25 years ago.

  5. Non-invasive (and minimally invasive) diagnosis of oesophageal varices.

    PubMed

    de Franchis, Roberto

    2008-10-01

    Current guidelines recommend screening all cirrhotic patients by endoscopy, to identify patients at risk of bleeding who should undergo prophylactic treatment. However, since the prevalence of varices in cirrhotic patients is variable, universal screening would imply a large number of unnecessary endoscopies and a heavy burden for endoscopy units. In addition, compliance to screening programs may be hampered by the perceived unpleasantness of endoscopy. Predicting the presence of oesophageal varices by non-invasive means might increase compliance and would permit to restrict the performance of endoscopy to those patients with a high probability of having varices. Over the years, several studies have addressed this issue by assessing the potential of biochemical, clinical and ultrasound parameters, transient elastography, CT scanning and video capsule endoscopy. The platelet count/spleen diameter ratio, CT scanning and video capsule endoscopy have shown promising performance characteristics, although none of them is equivalent to EGD. These methods are perceived by patients as preferable to endoscopy and thus might increase adherence to screening programs. Whether this will compensate for the lower sensitivity of these alternative techniques, and ultimately improve the outcomes if more patients undergo screening, is the crucial question that will have to be answered in the future.

  6. Non-invasive thermometry with multi-frequency microwave radiometry.

    PubMed

    Mizushina, S; Shimizu, T; Sugiura, T

    1992-01-01

    The present status of the development of a non-invasive thermometer based on microwave radiometry at our laboratory is reported. We have developed a model fitting technique combined with a Monte Carlo technique to retrieve temperature-depth profiles from multi (4-6)-frequency-band microwave radiometric data along with confidence intervals (2-sigma) of tissue temperatures as a function of depth. In order to make the radiometric technique compatible with the heating, brightness temperatures are measured through a 1 cm thick water bolus. Results of phantom experiments are presented to demonstrate the above capabilities of the method. Numerical simulation studies have shown that 2-sigma intervals would be 1.0 K or less over a 0-4 cm range and 1.4 K at 5 cm from the surface with using a six-band, 1-5 GHz radiometer having brightness temperature resolution of 0.03 K (3 s integration time). The six-band instrument is currently being assembled at our laboratory.

  7. Public viewpoints on new non-invasive prenatal genetic tests.

    PubMed

    Farrimond, Hannah R; Kelly, Susan E

    2013-08-01

    Prenatal screening programmes have been critiqued for their routine implementation according to clinical rationale without public debate. A new approach, non-invasive prenatal diagnosis (NIPD), promises diagnosis of fetal genetic disorders from a sample of maternal blood without the miscarriage risk of current invasive prenatal tests (e.g. amniocentesis). Little research has investigated the attitudes of wider publics to NIPD. This study used Q-methodology, which combines factor analysis with qualitative comments, to identify four distinct "viewpoints" amongst 71 UK men and women: 1. NIPD as a new tool in the ongoing societal discrimination against the disabled; 2. NIPD as a positive clinical application offering peace of mind in pregnancy; 3. NIPD as a medical option justified for severe disorders only; and 4. NIPD as a valid expansion of personal choice. Concerns included the "trivialisation of testing" and the implications of commercial/direct-to-consumer tests. Q-methodology has considerable potential to identify viewpoints and frame public debate about new technologies.

  8. Application of optical non-invasive methods in skin physiology

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Patzelt, A.; Darvin, M.; Richter, H.; Antoniou, C.; Sterry, W.; Koch, S.

    2008-05-01

    In the present paper the application of optical non-invasive methods in dermatology and cosmetology is discussed. Laser scanning microscopy (LSM) and optical coherent tomography (OCT) are the most promising methods for this application. Using these methods, the analysis of different skin parameters like dryness and oiliness of the skin, the barrier function and the structure of furrows and wrinkles are discussed. Additionally the homogeneity of distribution of topically applied creams, as well as their penetration into the skin were investigated. It is shown that these methods are highly valuable in dermatology for diagnostic and therapy control and for basic research, for instance in the field of structure analysis of hair follicles and sweat glands. The vertical images of the tissue produced by OCT can be easily compared with histological sections. Unfortunately, the resolution of the OCT technique is not high enough to carry out measurements on a cellular level, as is possible by LSM. LSM has the advantage that it can be used for the investigation of penetration and storage processes of topically applied substances, if these substances have fluorescent properties or if they are fluorescent-labelled.

  9. Reducing proactive aggression through non-invasive brain stimulation.

    PubMed

    Dambacher, Franziska; Schuhmann, Teresa; Lobbestael, Jill; Arntz, Arnoud; Brugman, Suzanne; Sack, Alexander T

    2015-10-01

    Aggressive behavior poses a threat to human collaboration and social safety. It is of utmost importance to identify the functional mechanisms underlying aggression and to develop potential interventions capable of reducing dysfunctional aggressive behavior already at a brain level. We here experimentally shifted fronto-cortical asymmetry to manipulate the underlying motivational emotional states in both male and female participants while assessing the behavioral effects on proactive and reactive aggression. Thirty-two healthy volunteers received either anodal transcranial direct current stimulation to increase neural activity within right dorsolateral prefrontal cortex, or sham stimulation. Aggressive behavior was measured with the Taylor Aggression Paradigm. We revealed a general gender effect, showing that men displayed more behavioral aggression than women. After the induction of right fronto-hemispheric dominance, proactive aggression was reduced in men. This study demonstrates that non-invasive brain stimulation can reduce aggression in men. This is a relevant and promising step to better understand how cortical brain states connect to impulsive actions and to examine the causal role of the prefrontal cortex in aggression. Ultimately, such findings could help to examine whether the brain can be a direct target for potential supportive interventions in clinical settings dealing with overly aggressive patients and/or violent offenders.

  10. Non invasive tools for the diagnosis of liver cirrhosis.

    PubMed

    Soresi, Maurizio; Giannitrapani, Lydia; Cervello, Melchiorre; Licata, Anna; Montalto, Giuseppe

    2014-12-28

    Liver cirrhosis (LC), the end stage of many forms of chronic hepatitis of different etiologies is a diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules surrounded by annular fibrosis. This chronic progressive clinical condition, leads to liver cell failure and portal hypertension, which can favour the onset of hepatocellular carcinoma. Defining the phase of the natural history is crucial for therapeutic choice and prognosis. Liver biopsy is currently considered the best available standard of reference but it has some limits, so alternative tools have been developed to substitute liver biopsy when assessing liver fibrosis. Serum markers offer a cost-effective alternative to liver biopsy being less invasive and theoretically without complications. They can be classified into direct and indirect markers which may be used alone or in combination to produce composite scores. Diagnostic imaging includes a number of instruments and techniques to estimate liver fibrosis and cirrhosis like ultrasound (US), US Doppler, contrast enhanced US and Elastography. US could be used for the diagnosis of advanced LC while is not able to evaluate progression of fibrosis, in this case Elastography is more reliable. This review aims to revise the most recent data from the literature about non invasive methods useful in defining liver fibrosis.

  11. Uncovering Multisensory Processing through Non-Invasive Brain Stimulation.

    PubMed

    Bolognini, Nadia; Maravita, Angelo

    2011-01-01

    Most of current knowledge about the mechanisms of multisensory integration of environmental stimuli by the human brain derives from neuroimaging experiments. However, neuroimaging studies do not always provide conclusive evidence about the causal role of a given area for multisensory interactions, since these techniques can mainly derive correlations between brain activations and behavior. Conversely, techniques of non-invasive brain stimulation (NIBS) represent a unique and powerful approach to inform models of causal relations between specific brain regions and individual cognitive and perceptual functions. Although NIBS has been widely used in cognitive neuroscience, its use in the study of multisensory processing in the human brain appears a quite novel field of research. In this paper, we review and discuss recent studies that have used two techniques of NIBS, namely transcranial magnetic stimulation and transcranial direct current stimulation, for investigating the causal involvement of unisensory and heteromodal cortical areas in multisensory processing, the effects of multisensory cues on cortical excitability in unisensory areas, and the putative functional connections among different cortical areas subserving multisensory interactions. The emerging view is that NIBS is an essential tool available to neuroscientists seeking for causal relationships between a given area or network and multisensory processes. With its already large and fast increasing usage, future work using NIBS in isolation, as well as in conjunction with different neuroimaging techniques, could substantially improve our understanding of multisensory processing in the human brain.

  12. Non-invasive screening for colorectal cancer in Asia.

    PubMed

    Chiu, Han-Mo; Chang, Li-Chun; Hsu, Wen-Feng; Chou, Chu-Kuang; Wu, Ming-Shiang

    2015-12-01

    There is an increasing trend of colorectal cancer incidence in Asia and nearly 45% of CRC cases worldwide occur in Asia therefore screening for CRC becomes an urgent task. Stool-based tests, including guaiac fecal occult blood test (gFOBT) and fecal immunochemical test (FIT), can select subjects at risk of significant colorectal neoplasms from the large target population thus are currently the most commonly used non-invasive screening tool in large population screening programs. FIT has the advantage over gFOBT in terms of higher sensitivity for early neoplasms, the ability to provide high-throughput automatic analysis, and better public acceptance thus greater effectiveness on reducing CRC mortality and incidence is expected. Owing to the large target population and constrained endoscopic capacity and manpower, FIT is nowadays the most popular CRC screening test in Asia. Some Asian countries have launched nationwide screening program in the past one or two decades but also encountered some challenges such as low screening participation rate, low verification rate after positive stool tests, low public awareness, and insufficient manpower. In addition, some controversial or potential future research issues are also addressed in this review.

  13. Alteration of Political Belief by Non-invasive Brain Stimulation

    PubMed Central

    Chawke, Caroline; Kanai, Ryota

    2016-01-01

    People generally have imperfect introspective access to the mechanisms underlying their political beliefs, yet can confidently communicate the reasoning that goes into their decision making process. An innate desire for certainty and security in ones beliefs may play an important and somewhat automatic role in motivating the maintenance or rejection of partisan support. The aim of the current study was to clarify the role of the DLPFC in the alteration of political beliefs. Recent neuroimaging studies have focused on the association between the DLPFC (a region involved in the regulation of cognitive conflict and error feedback processing) and reduced affiliation with opposing political candidates. As such, this study used a method of non-invasive brain simulation (tRNS) to enhance activity of the bilateral DLPFC during the incorporation of political campaign information. These findings indicate a crucial role for this region in political belief formation. However, enhanced activation of DLPFC does not necessarily result in the specific rejection of political beliefs. In contrast to the hypothesis the results appear to indicate a significant increase in conservative values regardless of participant's initial political orientation and the political campaign advertisement they were exposed to. PMID:26834603

  14. Development of a FBG probe for non-invasive carotid pulse waveform assessment

    NASA Astrophysics Data System (ADS)

    Leitão, C.; Bilro, L.; Alberto, N.; Antunes, P.; Lima, H.; André, P. S.; Nogueira, R.; Pinto, J. L.

    2012-06-01

    One of the early predictors of cardiovascular diseases, with growing interest, is the arterial stiffness which is typically evaluated through the velocity and morphology of the arterial pressure wave. In each cardiac cycle the heart generates a pressure wave which propagates through the arterial tree. Along its path, the pressure wave interacts with the arterial walls and, consequently, the morphology of a local arterial pressure wave can be assessed by the arterial distention movement. Due to its superficiality, proximity of the heart and high probability of atherosclerosis development, the carotid artery has particular interest to be monitored. In this work, the development of a non-invasive fibre Bragg grating (FBG) probe for the acquisition of the arterial distention wave is presented. Comparing to traditional methods, optical FBG based sensors can offer many advantages, namely, compactness, immunity to electromagnetic interference, high sensitivity, low noise and immunity to light source intensity due to its codification in the wavelength domain. The arterial movements induce strain on a uniform FBG, with the arterial distention pattern. The carotid pulse wave was successful accessed in young human carotid artery, with an acquisition rate of 950 Hz, allowing a clear distinction of the carotid pulse identification points.

  15. A Non-Invasive Assessment of Cardiopulmonary Hemodynamics with MRI in Pulmonary Hypertension

    PubMed Central

    Bane, Octavia; Shah, Sanjiv J.; Cuttica, Michael J.; Collins, Jeremy D.; Selvaraj, Senthil; Chatterjee, Neil R.; Guetter, Christoph; Carr, James C.; Carroll, Timothy J.

    2015-01-01

    Purpose We propose a method for non-invasive quantification of hemodynamic changes in the pulmonary arteries resulting from pulmonary hypertension (PH). Methods Using a two-element windkessel model, and input parameters derived from standard MRI evaluation of flow, cardiac function and valvular motion, we derive: pulmonary artery compliance (C), mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), pulmonary capillary wedge pressure (PCWP), time-averaged intra-pulmonary pressure waveforms and pulmonary artery pressures (systolic (sPAP) and diastolic (dPAP)). MRI results were compared directly to reference standard values from right heart catheterization (RHC) obtained in a series of patients with suspected pulmonary hypertension (PH). Results In 7 patients with suspected PH undergoing RHC, MRI and echocardiography, there was no statistically significant difference (p<0.05) between parameters measured by MRI and RHC. Using standard clinical cutoffs to define PH (mPAP ≥ 25 mmHg), MRI was able to correctly identify all patients as having pulmonary hypertension, and to correctly distinguish between pulmonary arterial (mPAP≥ 25 mmHg, PCWP<15 mmHg) and venous hypertension (mPAP ≥ 25 mmHg, PCWP ≥ 15 mmHg) in 5 of 7 cases. Conclusions We have developed a mathematical model capable of quantifying physiological parameters that reflect the severity of PH. PMID:26283577

  16. Thallium-201 perfusion imaging with atrial pacing or dipyridamole stress testing for evaluation of cardiac risk prior to nonvascular surgery

    SciTech Connect

    Stratmann, H.G.; Mark, A.L.; Williams, G.A. )

    1990-09-01

    Preoperative assessment of cardiac risk using thallium-201 scintigraphy and atrial pacing (n = 42) or dipyridamole stress testing (n = 35) was performed in 77 patients (mean age 65 +/- 7 years), who subsequently underwent elective nonvascular surgery. All patients were at low cardiac risk by clinical criteria; none could perform exercise stress testing due to physical limitations. ST depression consistent with ischemia occurred in 11 patients during atrial pacing and in 1 patient during dipyridamole stress testing (p less than 0.01). Nine patients had reversible perfusion defects with atrial pacing, and 10 patients with dipyridamole stress testing; fixed defects were present in 15 and 8 patients, respectively. Only one patient (fixed perfusion defect with atrial pacing, left main disease on coronary angiography) underwent preoperative coronary revascularization. Two patients subsequently had postoperative cardiac events. One patient (reversible perfusion defect with dipyridamole stress testing) experienced sudden death after a nonvascular procedure, while a second patient (normal thallium images with dipyridamole testing) had a nonfatal myocardial infarction. In patients having atrial pacing or dipyridamole stress testing, thallium-201 scans that are normal or show only a fixed perfusion defect confirm a low risk of cardiac complications following nonvascular surgery. The presence of a reversible perfusion defect does not preclude a postoperative course free of cardiac complications in patients at low cardiac risk by clinical criteria.

  17. The early identification of psychosis: Can lessons be learnt from Cardiac Stress Testing?

    PubMed Central

    Gupta, Swapnil; Ranganathan, Mohini; D’Souza, Deepak Cyril

    2015-01-01

    Psychotic disorders including schizophrenia are amongst the most debilitating psychiatric disorders. There is an urgent need to develop methods to identify individuals at risk with greater precision and as early as possible. At present, a prerequisite for a diagnosis of schizophrenia is the occurrence of a psychotic episode. Therefore, attempting to detect schizophrenia on the basis of psychosis is analogous to diagnosing coronary artery disease (CAD) after the occurrence of a myocardial infarction (MI). The introduction of cardiac stress testing (CST) has revolutionized the detection of CAD and the prevention and management of angina and MI. In this paper we attempt to apply lessons learnt from cardiac stress testing to the early detection of psychosis by proposing the development of an analogous psychosis stress test. We discuss in detail the various parameters of a proposed psychosis stress test including the choice of a suitable psychological or psychopharmacological “stressor”, target population, outcome measures, safety of the approach and the necessary evolution of test to become clinically informative. The history of evolution of CST may guide the development of a similar approach for the detection and management of psychotic disorders. The initial development of a test to unmask latent risk for schizophrenia will require the selection of a suitable and safe stimulus and the development of outcome measures as a prelude to testing in populations with a range of risk to determine predictive value. The use of cardiac stress testing in coronary artery disease offers the intriguing possibility that a similar approach may be applied to the detection and management of schizophrenia. PMID:26566609

  18. Non-invasive Thrombolysis using Microtripsy: A Parameter Study

    PubMed Central

    Zhang, Xi; Jin, Lifang; Vlaisavljevich, Eli; Owens, Gabe E.; Gurm, Hitinder S.; Cain, Charles A.; Xu, Zhen

    2016-01-01

    Histotripsy fractionates soft tissue by well-controlled acoustic cavitation using microsecond-long, high-intensity ultrasound pulses. The feasibility of using histotripsy as a non-invasive, drug-free, and image-guided thrombolysis method has been shown previously. A new histotripsy approach, termed Microtripsy, has recently been investigated for the thrombolysis application to improve treatment accuracy and avoid potential vessel damage. In this study, we investigated the effects of pulse repetition frequency (PRF) on microtripsy thrombolysis. Microtripsy thrombolysis treatments using different PRFs (5, 50, and 100 Hz) and doses (20, 50, and 100 pulses) were performed on blood clots in an in vitro vessel flow model. To quantitatively evaluate the microtripsy thrombolysis effect, the location of focal cavitation, the incident rate of pre-focal cavitation on the vessel wall, the size and location of the resulting flow channel, and the generated clot debris particles were measured. The results demonstrated that focal cavitation was always well-confined in the vessel lumen without contacting the vessel wall for all PRFs. Pre-focal cavitation on the front vessel wall was never observed at 5Hz PRF, but occasionally observed at PRFs of 50 Hz (1.2%) and 100 Hz (5.4%). However, the observed pre-focal cavitation was weak and didn’t significantly impact the focal cavitation. Results further demonstrated that, although the extent of clot fractionation per pulse was the highest at 5 Hz PRF at the beginning of treatment (<20 pulses), 100 Hz PRF generated the largest flow channels with a much shorter treatment time. Finally, results showed fewer large debris particles were generated at a higher PRF. Overall, the results of this study suggest that a higher PRF (50 or 100 Hz) may be a better choice for microtripsy thrombolysis to use clinically due to the larger resulting flow channel, shorter treatment time, and smaller debris particles. PMID:26670850

  19. Non-invasive evaluation of facial crestal bone with ultrasonography

    PubMed Central

    Sinjab, Khaled; Chung, Ming-Pang; Chiang, Yi-Chen; Wang, Hom-Lay; Giannobile, William V.; Kripfgans, Oliver D.

    2017-01-01

    Purpose Facial crestal bone level and dimension determine function and esthetics of dentition and dental implants. We have previously demonstrated that ultrasound can identify bony and soft tissue structures in the oral cavity. The aim of this study is to evaluate the accuracy of using ultrasound to measure facial crestal bone level and thickness. Materials and methods A commercially available medical ultrasound scanner, paired with a 14 MHz imaging probe was used to scan dental and periodontal tissues at the mid-facial site of each tooth on 6 fresh cadavers. The alveolar crest level in relation to the cemento-enamel junction and its thickness on ultrasound images were measured and compared to those on cone-beam computed tomography (CBCT) scans and/or direct measurements on a total of 144 teeth. Results The mean crestal bone level measured by means of ultrasound, CBCT and direct measures was 2.66 ± 0.86 mm, 2.51 ± 0.82 mm, and 2.71 ± 1.04 mm, respectively. The mean crestal bone thickness was 0.71 ± 0.44 mm and 0.74 ± 0.34 mm, measured by means of ultrasound and CBCT, respectively. The correlations of the ultrasound readings to the other two methods were between 0.78 and 0.88. The mean absolute differences in crestal bone height and thickness between ultrasound and CBCT were 0.09 mm (-1.20 to 1.00 mm, p = 0.06) and 0.03 mm (-0.48 to 0.54 mm, p = 0.03), respectively. Conclusion Ultrasound was as accurate in determining alveolar bone level and its thickness as CBCT and direct measurements. Clinical trials will be required to further validate this non-ionizing and non-invasive method for determining facial crestal bone position and dimension. PMID:28178323

  20. Non-invasive Brain Stimulation for Essential Tremor

    PubMed Central

    Shih, Ludy C.; Pascual-Leone, Alvaro

    2017-01-01

    Background There is increasing interest in the use of non-invasive brain stimulation to characterize and potentially treat essential tremor (ET). Studies have used a variety of stimulation coils, paradigms, and target locations to make these observations. We reviewed the literature to compare prior studies and to evaluate the rationale and the methods used in these studies. Methods We performed a systematic literature search of the PubMed database using the terms “transcranial,” “noninvasive,” “brain stimulation,” “transcranial magnetic stimulation (TMS),” “transcranial direct current stimulation (tDCS),” “transcranial alternating current stimulation (tACS),” and “essential tremor.” Results Single pulses of TMS to the primary motor cortex have long been known to reset tremor. Although there are relatively few studies showing alterations in motor cortical physiology, such as motor threshold, short and long intracortical inhibition, and cortical silent period, there may be some evidence of altered intracortical facilitation and cerebello-brain inhibition in ET. Repetitive TMS, theta burst stimulation, tDCS, and tACS have been applied to human subjects with tremor with some preliminary signs of tremor reduction, particularly in those studies that employed consecutive daily sessions. Discussion A variety of stimulation paradigms and targets have been explored, with the increasing rationale an interest in targeting the cerebellum. Rigorous assessment of coil geometry, stimulation paradigm, rationale for selection of the specific anatomic target, and careful phenotypic and physiologic characterization of the subjects with ET undergoing these interventions may be critical in extending these preliminary findings into effective stimulation therapies. PMID:28373927

  1. Early non-invasive ventilation treatment for severe influenza pneumonia.

    PubMed

    Masclans, J R; Pérez, M; Almirall, J; Lorente, L; Marqués, A; Socias, L; Vidaur, L; Rello, J

    2013-03-01

    The role of non-invasive ventilation (NIV) in acute respiratory failure caused by viral pneumonia remains controversial. Our objective was to evaluate the use of NIV in a cohort of (H1N1)v pneumonia. Usefulness and success of NIV were assessed in a prospective, observational registry of patients with influenza A (H1N1) virus pneumonia in 148 Spanish intensive care units (ICUs) in 2009-10. Significant variables for NIV success were included in a multivariate analysis. In all, 685 patients with confirmed influenza A (H1N1)v viral pneumonia were admitted to participating ICUs; 489 were ventilated, 177 with NIV. The NIV was successful in 72 patients (40.7%), the rest required intubation. Low Acute Physiology and Chronic Health Evaluation (APACHE) II, low Sequential Organ Failure Assessment (SOFA) and absence of renal failure were associated with NIV success. Success of NIV was independently associated with fewer than two chest X-ray quadrant opacities (OR 3.5) and no vasopressor requirement (OR 8.1). However, among patients with two or more quadrant opacities, a SOFA score ≤7 presented a higher success rate than those with SOFA score >7 (OR 10.7). Patients in whom NIV was successful required shorter ventilation time, shorter ICU stay and hospital stay than NIV failure. In patients in whom NIV failed, the delay in intubation did not increase mortality (26.5% versus 24.2%). Clinicians used NIV in 25.8% of influenza A (H1N1)v viral pneumonia admitted to ICU, and treatment was effective in 40.6% of them. NIV success was associated with shorter hospital stay and mortality similar to non-ventilated patients. NIV failure was associated with a mortality similar to those who were intubated from the start.

  2. Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis

    PubMed Central

    Crosara, Stefano; D'Onofrio, Mirko; De Robertis, Riccardo; Demozzi, Emanuele; Canestrini, Stefano; Zamboni, Giulia; Pozzi Mucelli, Roberto

    2014-01-01

    Autoimmune pancreatitis (AIP) is characterized by obstructive jaundice, a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate, with or without a pancreatic mass. Type 1 AIP is the pancreatic manifestation of an IgG4-related systemic disease and is characterized by elevated IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic lesions. Type 2 AIP usually has none or very few IgG4-positive plasma cells, no serum IgG4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement. AIP is diagnosed in approximately 2%-6% of patients that undergo pancreatic resection for suspected pancreatic cancer. There are three patterns of autoimmune pancreatitis: diffuse disease is the most common type, with a diffuse, “sausage-like” pancreatic enlargement with sharp margins and loss of the lobular contours; focal disease is less common and manifests as a focal mass, often within the pancreatic head, mimicking a pancreatic malignancy. Multifocal involvement can also occur. In this paper we describe the features of AIP at ultrasonography, computed tomography, magnetic resonance and positron emission tomography/computed tomography imaging, focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma. It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients. Non-invasive imaging plays also an important role in therapy monitoring, in follow-up and in early identification of disease recurrence. PMID:25493001

  3. Using new non-invasive quick method to detect Borrelia Burgdorferi (B.B.) infection from specific parts of the heart in "seemingly normal" ECGs, and from the ECGs of Atrial Fibrillation (AF), a majority of AF ECGs are found to have: 1) Significant B.B. infection, 2) Markedly increased ANP, 3) Increased Cardiac Troponin I & 4) Markedly reduced Taurine. These 4 factors were mainly localized at infected areas of the SA node area, R-&L-Atria & pulmonary veins at the L-atrium.

    PubMed

    Omura, Yoshiaki; Lu, Dominic; Jones, Marilyn K; Nihrane, Abdallah; Duvvi, Harsha; Yapor, Dario; Shimotsuura, Yasuhiro; Ohki, Motomu

    2015-01-01

    Lyme disease is found in a majority of people we tested. Once Borrelia Burgdorferi (B.B.) spirochete enters human body, it not only causes pain by infecting joints, but it also often enters the brain and the heart. Infection of brain can be quickly detected from the pupil and infection of the heart by ECGs non-invasively. By evaluating recorded ECGs of atrial fibrillation (AF), using U.S. patented non-invasive highly sensitive electromagnetic field (EMF) resonance phenomenon between 2 identical molecules or between a molecule and its antibody, we examined 25 different AF patients' ECGs and found the majority of them suffer from various degrees of B.B. spirochete infection in SA node areas, also in the right & left atria, and pulmonary vein near and around its junction at left atrium & lesser degrees of infection at the AV node & His Bundle. When B.B. infection reaches over 224-600ng or higher at these areas, AF often appears in the majority of all AF analyzed. In order to develop AF, the 4 abnormal factors must be present simultaneously: 1) B.B. infection must be increased to 224-600ng or higher, 2) Atrial Natriuretic Peptide (ANP) must be markedly reduced from normal value of less than 4ng to over 100-400ng, 3) A significant increase of Cardiac Troponin I from normal value of less than 3ng to over 12ng and 4) Taurine must also be markedly reduced from normal value of 4-6ng to 0.25ng. These 4 changes were mainly found only at infected sites of the SA node area, both atria and between the end of the T wave & the beginning of the SA node area, which corresponds to U waves at recorded ECG. Origin of the U wave is mainly due to abnormal electrical potential of pulmonary vein at L-atrium. If all 4 factors do not occur at the infection site, no AF will develop. In seemingly normal ECGs, if using this method, one can detect invisible B.B. infection in early stages. Long before AF appears, AF can be prevented by improved treatment with Amoxicillin 500ng 3 times

  4. Relationship of radionuclide indexes of cardiac function during interventions: volume loading, afterload stress, exercise, and pacing

    SciTech Connect

    Slutsky, R.A.

    1983-04-01

    We compared three radionuclide index of cardiac function: 1) the ejection fraction (EF), 2) the mean ejection rate (ER), and 3) the mean velocity of circumferential fiber shortening (MVCF) during volume loading, phenylephrine hydrochloride stress, exercise, and atrial pacing. All behaved in a similar (linear) fashion, allowing appropriate hemodynamic conclusions to be drawn using either index. During atrial pacing, the ejection fraction declined when velocity indexes increased, suggesting that the ejection fraction may not be a suitable index to characterize alterations in inotropic state during rapid alterations in heart rate, particular in the absence of angina pectoris. This may result from the reductions in cardiac volume for the duration of pacing, where the velocity index is preserved. In most circumstances excluding atrial pacing, ejection fraction during interventions is an adequate index of the change of myocardial contractile state. Overall, radionuclide angiography is an excellent technique to characterize acute hemodynamic interventions, with ejection fraction, in general, the simplest and most reliable of cardiac indexes during stress interventions.

  5. Seasonal and latitudinal acclimatization of cardiac transcriptome responses to thermal stress in porcelain crabs, Petrolisthes cinctipes.

    PubMed

    Stillman, Jonathon H; Tagmount, Abderrahmane

    2009-10-01

    Central predictions of climate warming models include increased climate variability and increased severity of heat waves. Physiological acclimatization in populations across large-scale ecological gradients in habitat temperature fluctuation is an important factor to consider in detecting responses to climate change related increases in thermal fluctuation. We measured in vivo cardiac thermal maxima and used microarrays to profile transcriptome heat and cold stress responses in cardiac tissue of intertidal zone porcelain crabs across biogeographic and seasonal gradients in habitat temperature fluctuation. We observed acclimatization dependent induction of heat shock proteins, as well as unknown genes with heat shock protein-like expression profiles. Thermal acclimatization had the largest effect on heat stress responses of extensin-like, beta tubulin, and unknown genes. For these genes, crabs acclimatized to thermally variable sites had higher constitutive expression than specimens from low variability sites, but heat stress dramatically induced expression in specimens from low variability sites and repressed expression in specimens from highly variable sites. Our application of ecological transcriptomics has yielded new biomarkers that may represent sensitive indicators of acclimatization to habitat temperature fluctuation. Our study also has identified novel genes whose further description may yield novel understanding of cellular responses to thermal acclimatization or thermal stress.

  6. Regulation of mitochondrial oxidative stress by β-arrestins in cultured human cardiac fibroblasts

    PubMed Central

    Philip, Jennifer L.; Razzaque, Md. Abdur; Han, Mei; Li, Jinju; Theccanat, Tiju; Xu, Xianyao; Akhter, Shahab A.

    2015-01-01

    ABSTRACT Oxidative stress in cardiac fibroblasts (CFs) promotes transformation to myofibroblasts and collagen synthesis leading to myocardial fibrosis, a precursor to heart failure (HF). NADPH oxidase 4 (Nox4) is a major source of cardiac reactive oxygen species (ROS); however, mechanisms of Nox4 regulation are unclear. β-arrestins are scaffold proteins that signal in G-protein-dependent and -independent pathways; for example, in ERK activation. We hypothesize that β-arrestins regulate oxidative stress in a Nox4-dependent manner and increase fibrosis in HF. CFs were isolated from normal and failing adult human left ventricles. Mitochondrial ROS/superoxide production was quantitated using MitoSox. β-arrestin and Nox4 expressions were manipulated using adenoviral overexpression or short interfering RNA (siRNA)-mediated knockdown. Mitochondrial oxidative stress and Nox4 expression in CFs were significantly increased in HF. Nox4 knockdown resulted in inhibition of mitochondrial superoxide production and decreased basal and TGF-β-stimulated collagen and α-SMA expression. CF β-arrestin expression was upregulated fourfold in HF. β-arrestin knockdown in failing CFs decreased ROS and Nox4 expression by 50%. β-arrestin overexpression in normal CFs increased mitochondrial superoxide production twofold. These effects were prevented by inhibition of either Nox or ERK. Upregulation of Nox4 seemed to be a primary mechanism for increased ROS production in failing CFs, which stimulates collagen deposition. β-arrestin expression was upregulated in HF and plays an important and newly identified role in regulating mitochondrial superoxide production via Nox4. The mechanism for this effect seems to be ERK-mediated. Targeted inhibition of β-arrestins in CFs might decrease oxidative stress as well as pathological cardiac fibrosis. PMID:26449263

  7. Non-Invasive Investigation of Bone Adaptation in Humans to Mechanical Loading

    NASA Technical Reports Server (NTRS)

    Whalen, R.

    1999-01-01

    Experimental studies have identified peak cyclic forces, number of loading cycles, and loading rate as contributors to the regulation of bone metabolism. We have proposed a theoretical model that relates bone density to a mechanical stimulus derived from average daily cumulative peak cyclic 'effective' tissue stresses. In order to develop a non-invasive experimental model to test the theoretical model we need to: (1) monitor daily cumulative loading on a bone, (2) compute the internal stress state(s) resulting from the imposed loading, and (3) image volumetric bone density accurately, precisely, and reproducibly within small contiguous volumes throughout the bone. We have chosen the calcaneus (heel) as an experimental model bone site because it is loaded by ligament, tendon and joint contact forces in equilibrium with daily ground reaction forces that we can measure; it is a peripheral bone site and therefore more easily and accurately imaged with computed tomography; it is composed primarily of cancellous bone; and it is a relevant site for monitoring bone loss and adaptation in astronauts and the general population. This paper presents an overview of our recent advances in the areas of monitoring daily ground reaction forces, biomechanical modeling of the forces on the calcaneus during gait, mathematical modeling of calcaneal bone adaptation in response to cumulative daily activity, accurate and precise imaging of the calcaneus with quantitative computed tomography (QCT), and application to long duration space flight.

  8. Normoxic resuscitation after cardiac arrest protects against hippocampal oxidative stress, metabolic dysfunction, and neuronal death

    PubMed Central

    Vereczki, Viktoria; Martin, Erica; Rosenthal, Robert E; Hof, Patrick R; Hoffman, Gloria E; Fiskum, Gary

    2008-01-01

    Resuscitation and prolonged ventilation using 100% oxygen after cardiac arrest is standard clinical practice despite evidence from animal models indicating that neurologic outcome is improved using normoxic compared with hyperoxic resuscitation. This study tested the hypothesis that normoxic ventilation during the first hour after cardiac arrest in dogs protects against prelethal oxidative stress to proteins, loss of the critical metabolic enzyme pyruvate dehydrogenase complex (PDHC), and minimizes subsequent neuronal death in the hippocampus. Anesthetized beagles underwent 10 mins ventricular fibrillation cardiac arrest, followed by defibrillation and ventilation with either 21% or 100% O2. At 1 h after resuscitation, the ventilator was adjusted to maintain normal blood gas levels in both groups. Brains were perfusion-fixed at 2 h reperfusion and used for immunohistochemical measurements of hippocampal nitrotyrosine, a product of protein oxidation, and the E1α subunit of PDHC. In hyperoxic dogs, PDHC immunostaining diminished by approximately 90% compared with sham-operated dogs, while staining in normoxic animals was not significantly different from nonischemic dogs. Protein nitration in the hippocampal neurons of hyperoxic animals was 2–3 times greater than either sham-operated or normoxic resuscitated animals at 2 h reperfusion. Stereologic quantification of neuronal death at 24 h reperfusion showed a 40% reduction using normoxic compared with hyperoxic resuscitation. These results indicate that postischemic hyperoxic ventilation promotes oxidative stress that exacerbates prelethal loss of pyruvate dehydrogenase and delayed hippocampal neuronal cell death. Moreover, these findings indicate the need for clinical trials comparing the effects of different ventilatory oxygen levels on neurologic outcome after cardiac arrest. PMID:16251887

  9. Label-free imaging of metabolism and oxidative stress in human induced pluripotent stem cell-derived cardiomyocytes

    PubMed Central

    Datta, Rupsa; Heylman, Christopher; George, Steven C.; Gratton, Enrico

    2016-01-01

    In this work we demonstrate a label-free optical imaging technique to assess metabolic status and oxidative stress in human induced pluripotent stem cell-derived cardiomyocytes by two-photon fluorescence lifetime imaging of endogenous fluorophores. Our results show the sensitivity of this method to detect shifts in metabolism and oxidative stress in the cardiomyocytes upon pathological stimuli of hypoxia and cardiotoxic drugs. This non-invasive imaging technique could prove beneficial for drug development and screening, especially for in vitro cardiac models created from stem cell-derived cardiomyocytes and to study the pathogenesis of cardiac diseases and therapy. PMID:27231614

  10. Label-free imaging of metabolism and oxidative stress in human induced pluripotent stem cell-derived cardiomyocytes.

    PubMed

    Datta, Rupsa; Heylman, Christopher; George, Steven C; Gratton, Enrico

    2016-05-01

    In this work we demonstrate a label-free optical imaging technique to assess metabolic status and oxidative stress in human induced pluripotent stem cell-derived cardiomyocytes by two-photon fluorescence lifetime imaging of endogenous fluorophores. Our results show the sensitivity of this method to detect shifts in metabolism and oxidative stress in the cardiomyocytes upon pathological stimuli of hypoxia and cardiotoxic drugs. This non-invasive imaging technique could prove beneficial for drug development and screening, especially for in vitro cardiac models created from stem cell-derived cardiomyocytes and to study the pathogenesis of cardiac diseases and therapy.

  11. Non-invasive ventilation in acute respiratory failure in children

    PubMed Central

    Abadesso, Clara; Nunes, Pedro; Silvestre, Catarina; Matias, Ester; Loureiro, Helena; Almeida, Helena

    2012-01-01

    The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO2 at 2, 6, 12 and 24 hours after NIV onset (P<0.05) in both groups. Improvement in pulse oximetric saturation/fraction of inspired oxygen (SpO2/FiO2) was verified at 2, 4, 6, 12 and 24 hours after NIV onset in the success group (P<0.001). In the failure group, significant SpO2/FiO2 improvement was only observed in the first 4 hours. NIV failure occurred in 34 patients (22.5%). Risk factors for NIV failure were apnea, prematurity, pneumonia, and bacterial co-infection (P<0.05). Independent risk factors for NIV failure were apneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42–71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33–111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection. PMID:22802994

  12. Cardiac reactivity and preserved performance under stress: two sides of the same coin?

    PubMed

    Pattyn, Nathalie; Mairesse, Olivier; Cortoos, Aisha; Morais, José; Soetens, Eric; Roelands, Bart; van den Nest, Annick; Kolinsky, Régine

    2014-07-01

    In the present experiment, cognitive control under stress was investigated using a real-life paradigm, namely an evaluation flight for military student pilots. The magnitude of cognitive interference on color-word, numerical and emotional Stroop paradigms was studied during a baseline recording and right before the test flight. Cardio-respiratory parameters were simultaneously assessed during rest and the performance of the Stroop tasks. Cognitive data suggested a different speed/accuracy trade-off under stress, and no modulation of the interference effect for color words or numerical stimuli. However, we observed a major increase in error rates for specific emotional stimuli related to the evaluation situation in the stress condition. The increase in cognitive interference from emotional stimuli, expressed as an increase in error rates, was correlated to the decreased cardiac reactivity to challenge in the stress situation. This relationship is discussed in the framework of Sanders' (1983) model of stress and performance. In terms of future research, this link warrants a fruitful lead to be followed for investigating the causal mechanism of performance decrements under the influence of stress.

  13. Evaluation of Stress Intensity and Anxiety Level in Preoperative Period of Cardiac Patients

    PubMed Central

    Rosiek, Anna; Kornatowski, Tomasz; Rosiek-Kryszewska, Aleksandra; Leksowski, Łukasz; Leksowski, Krzysztof

    2016-01-01

    Introduction. The stress related to patient's stay in a hospital increases when it is necessary to perform a surgery. Therefore, the study of the phenomenon of stress intensity in hospitalized patients has become an important issue for public health. Material and Method. The study was conducted in University Hospital No. 1 in the cardiosurgery clinic. The study involved 58 patients who were admitted as planned to the hospital. The study used a standardized questionnaire measuring intensity of the stress and also deepened interviews with patients about stress and anxiety felt before the surgery. Results. The greater the patient's anxiety resulting from his state of health, the greater the intensity of stress in the preoperative period. This relationship is linear. The results of the study also made it possible to see intrapersonal factors (pain, illness, and suffering) and extrapersonal factors (anesthesia, surgery, and complications after surgery), which are causes of anxiety before surgery. Conclusion. The research showed high (negative) results of anxiety and stress associated with the disease, surgery, and complications after cardiac surgery. Active involvement in hospitalization elements, such as patient education before surgery, psychological support, and medical care organization taking into account patient's preferences, reduces the impact of stressors. PMID:27042655

  14. Cardiac reflections and natural vibrations: Force-frequency relation recording system in the stress echo lab

    PubMed Central

    Bombardini, Tonino; Gemignani, Vincenzo; Bianchini, Elisabetta; Venneri, Lucia; Petersen, Christina; Pasanisi, Emilio; Pratali, Lorenza; Pianelli, Mascia; Faita, Francesco; Giannoni, Massimo; Picano, Eugenio

    2007-01-01

    Background The inherent ability of ventricular myocardium to increase its force of contraction in response to an increase in contraction frequency is known as the cardiac force-frequency relation (FFR). This relation can be easily obtained in the stress echo lab, where the force is computed as the systolic pressure/end-systolic volume index ratio, and measured for increasing heart rates during stress. Ideally, the noninvasive, imaging independent, objective assessment of FFR would greatly enhance its practical appeal. Objectives 1 – To evaluate the feasibility of the cardiac force measurement by a precordial cutaneous sensor. 2 – To build the curve of force variation as a function of the heart rate. 3 – To compare the standard stress echo results vs. this sensor operator-independent built FFR. Methods The transcutaneous force sensor was positioned in the precordial region in 88 consecutive patients referred for exercise, dipyridamole, or pacing stress. The force was measured as the myocardial vibrations amplitude in the isovolumic contraction period. FFR was computed as the curve of force variation as a function of heart rate. Standard echocardiographic FFR measurements were performed. Results A consistent FFR was obtained in all patients. Both the sensor built and the echo built FFR identifiy pts with normal or abnormal contractile reserve. The best cut-off value of the sensor built FFR was 15.5 g * 10-3 (Sensitivity = 0.85, Specificity = 0.77). Sensor built FFR slope and shape mirror pressure/volume relation during stress. This approach is extendable to daily physiological exercise and could be potentially attractive in home monitoring systems. PMID:18031588

  15. Stress echocardiography in warmblood horses: comparison of dobutamine/atropine with treadmill exercise as cardiac stressors.

    PubMed

    Gehlen, Heidrun; Marnette, Silke; Rohn, Karl; Stadler, Peter

    2006-01-01

    The purpose of this study was to determine whether the combination of dobutamine and atropine causes cardiac stress equivalent to treadmill exercise. Therefore, electrocardiography and echocardiography were performed on 10 warmblood horses before, during, and after different cardiac stress tests. Stressors consisted of a standardized treadmill exercise and combined administration of dobutamine (7.5 microg/kg/min) and atropine (5 microg/kg). Maxima heart rates were achieved during the treadmill exercise (175 +/- 10 bpm). After exercise, a rapid decrease in heart rate was observed. Subsequently, a stress echocardiography for which a heart rate >100 bpm was required could only be performed within 1 minute after exercise. The mean heart rate during echocardiography was 136 +/- 8 bpm after exercise. The combination of dobutamine and atropine also resulted in a significant increase in heart rate, up to 141 +/- 20 bpm. Maxima heart rate was significantly higher during the treadmill exercise, but the decrease in heart rate was significantly slower after dobutamine and atropine administration. Over a period of 7.9 minutes, the mean heart rate was 123 +/- 8 bpm during dobutamine and atropine administration. Consequently, the combination of both drugs offered sufficient time for detailed examinations. Overall, echocardiographic examination identified a decrease in left ventricular (LV) dimensions, an increase in LV wall thickness, and a decrease in stroke volume after the treadmill exercise and during pharmacologic stress testing compared with baseline. Changes in echocardiographic variables generally were more pronounced during dobutamine and atropine administration. Similar to stress echocardiography in humans, in horses the combination of dobutamine and atropine is useful to produce an increase in heart rate comparable with what is achieved with exercise but without the need of increasing dobutamine dosage.

  16. Hemoglobin-associated Oxidative Stress in the Pericardial Compartment of Post-operative Cardiac Surgery Patients

    PubMed Central

    Kramer, Philip A.; Chacko, Balu K.; Ravi, Saranya; Johnson, Michelle S.; Mitchell, Tanecia; Barnes, Stephen; Arabshahi, Alireza; Dell’Italia, Louis J.; George, David J.; Steele, Chad; George, James F.; Darley-Usmar, Victor M.; Melby, Spencer J.

    2015-01-01

    Atherosclerosis and valvular heart disease often require treatment with corrective surgery to prevent future myocardial infarction, ischemic heart disease, and heart failure. Mechanisms underlying the development of the associated complications of surgery are multifactorial and have been linked to inflammation and oxidative stress, classically as measured in the blood or plasma of patients. Post-operative pericardial fluid (PO-PCF) has not been investigated in depth with respect to the potential to induce oxidative stress. This is important since cardiac surgery disrupts the integrity of the pericardial membrane surrounding the heart, and causes significant alterations in the composition of the pericardial fluid (PCF). This includes contamination with hemolyzed blood and high concentrations of oxidized hemoglobin, which suggests that cardiac surgery results in oxidative stress within the pericardial space. Accordingly, we tested the hypothesis that PO-PCF is highly pro-oxidant and that the potential interaction between inflammatory cell-derived hydrogen peroxide with hemoglobin is associated with oxidative stress. Blood and PCF were collected from 31 patients at the time of surgery and postoperatively from 4 to 48 hours after coronary artery bypass grafting, valve replacement, or valve repair (mitral or aortic). PO-PCF contained high concentrations of neutrophils and monocytes which are capable of generating elevated amounts of superoxide and hydrogen peroxide through the oxidative burst. In addition, PO-PCF primed naïve neutrophils resulting in an enhanced oxidative burst upon stimulation. The PO-PCF also contained increased concentrations of cell-free oxidized hemoglobin which was associated with elevated levels of F2α-isoprostanes and prostaglandins, consistent with both oxidative stress and activation of cyclooxygenase. Lastly, protein analysis of the PO-PCF revealed evidence of protein thiol oxidation and protein carbonylation. We conclude that PO-PCF is

  17. Diagnosis of Chagas' cardiomyopathy. Non-invasive techniques.

    PubMed Central

    Puigbó, J. J.; Valecillos, R.; Hirschhaut, E.; Giordano, H.; Boccalandro, I.; Suárez, C.; Aparicio, J. M.

    1977-01-01

    The natural history of Chagas' disease and its manifestations when the heart is involved are detailed clinically and pathologically. Three phases are recognized: the acute phase, lasting from 1-3 months, the latent phase, which may last from 10-20 years, and the chronic phase, which has the most serious manifestations. This phase is subdivided into three clinical stages. An analysis of the varied cardiac manifestations on 235 patients is included. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:412174

  18. Popeye domain containing proteins are essential for stress-mediated modulation of cardiac pacemaking in mice

    PubMed Central

    Froese, Alexander; Breher, Stephanie S.; Waldeyer, Christoph; Schindler, Roland F.R.; Nikolaev, Viacheslav O.; Rinné, Susanne; Wischmeyer, Erhard; Schlueter, Jan; Becher, Jan; Simrick, Subreena; Vauti, Franz; Kuhtz, Juliane; Meister, Patrick; Kreissl, Sonja; Torlopp, Angela; Liebig, Sonja K.; Laakmann, Sandra; Müller, Thomas D.; Neumann, Joachim; Stieber, Juliane; Ludwig, Andreas; Maier, Sebastian K.; Decher, Niels; Arnold, Hans-Henning; Kirchhof, Paulus; Fabritz, Larissa; Brand, Thomas

    2012-01-01

    Cardiac pacemaker cells create rhythmic pulses that control heart rate; pacemaker dysfunction is a prevalent disorder in the elderly, but little is known about the underlying molecular causes. Popeye domain containing (Popdc) genes encode membrane proteins with high expression levels in cardiac myocytes and specifically in the cardiac pacemaking and conduction system. Here, we report the phenotypic analysis of mice deficient in Popdc1 or Popdc2. ECG analysis revealed severe sinus node dysfunction when freely roaming mutant animals were subjected to physical or mental stress. In both mutants, bradyarrhythmia developed in an age-dependent manner. Furthermore, we found that the conserved Popeye domain functioned as a high-affinity cAMP-binding site. Popdc proteins interacted with the potassium channel TREK-1, which led to increased cell surface expression and enhanced current density, both of which were negatively modulated by cAMP. These data indicate that Popdc proteins have an important regulatory function in heart rate dynamics that is mediated, at least in part, through cAMP binding. Mice with mutant Popdc1 and Popdc2 alleles are therefore useful models for the dissection of the mechanisms causing pacemaker dysfunction and could aid in the development of strategies for therapeutic intervention. PMID:22354168

  19. Costs and clinical outcomes for non-invasive versus invasive diagnostic approaches to patients with suspected in-stent restenosis.

    PubMed

    Min, James K; Hasegawa, James T; Machacz, Susanne F; O'Day, Ken

    2016-02-01

    This study compared costs and clinical outcomes of invasive versus non-invasive diagnostic evaluations for patients with suspected in-stent restenosis (ISR) after percutaneous coronary intervention. We developed a decision model to compare 2 year diagnosis-related costs for patients who presented with suspected ISR and were evaluated by: (1) invasive coronary angiography (ICA); (2) non-invasive stress testing strategy of myocardial perfusion imaging (MPI) with referral to ICA based on MPI; (3) coronary CT angiography-based testing strategy with referral to ICA based on CCTA. Costs were modeled from the payer's perspective using 2014 Medicare rates. 56 % of patients underwent follow-up diagnostic testing over 2 years. Compared to ICA, MPI (98.6 %) and CCTA (98.1 %) exhibited lower rates of correct diagnoses. Non-invasive strategies were associated with reduced referrals to ICA and costs compared to an ICA-based strategy, with diagnostic costs lower for CCTA than MPI. Overall 2-year costs were highest for ICA for both metallic as well as BVS stents ($1656 and $1656, respectively) when compared to MPI ($1444 and $1411) and CCTA. CCTA costs differed based upon stent size and type, and were highest for metallic stents >3.0 mm followed by metallic stents <3.0 mm, BVS < 3.0 mm and BVS > 3.0 mm ($1466 vs. $1242 vs. $855 vs. $490, respectively). MPI for suspected ISR results in lower costs and rates of complications than invasive strategies using ICA while maintaining high diagnostic performance. Depending upon stent size and type, CCTA results in lower costs than MPI.

  20. Costs and clinical outcomes for non-invasive versus invasive diagnostic approaches to patients with suspected in-stent restenosis

    PubMed Central

    Hasegawa, James T.; Machacz, Susanne F.; O’Day, Ken

    2015-01-01

    This study compared costs and clinical outcomes of invasive versus non-invasive diagnostic evaluations for patients with suspected in-stent restenosis (ISR) after percutaneous coronary intervention. We developed a decision model to compare 2 year diagnosis-related costs for patients who presented with suspected ISR and were evaluated by: (1) invasive coronary angiography (ICA); (2) non-invasive stress testing strategy of myocardial perfusion imaging (MPI) with referral to ICA based on MPI; (3) coronary CT angiography-based testing strategy with referral to ICA based on CCTA. Costs were modeled from the payer’s perspective using 2014 Medicare rates. 56 % of patients underwent follow-up diagnostic testing over 2 years. Compared to ICA, MPI (98.6 %) and CCTA (98.1 %) exhibited lower rates of correct diagnoses. Non-invasive strategies were associated with reduced referrals to ICA and costs compared to an ICA-based strategy, with diagnostic costs lower for CCTA than MPI. Overall 2-year costs were highest for ICA for both metallic as well as BVS stents ($1656 and $1656, respectively) when compared to MPI ($1444 and $1411) and CCTA. CCTA costs differed based upon stent size and type, and were highest for metallic stents >3.0 mm followed by metallic stents <3.0 mm, BVS < 3.0 mm and BVS > 3.0 mm ($1466 vs. $1242 vs. $855 vs. $490, respectively). MPI for suspected ISR results in lower costs and rates of complications than invasive strategies using ICA while maintaining high diagnostic performance. Depending upon stent size and type, CCTA results in lower costs than MPI. PMID:26335370

  1. Automated Non-invasive Video-Microscopy of Oyster Spat Heart Rate during Acute Temperature Change: Impact of Acclimation Temperature

    PubMed Central

    Domnik, Nicolle J.; Polymeropoulos, Elias T.; Elliott, Nicholas G.; Frappell, Peter B.; Fisher, John T.

    2016-01-01

    We developed an automated, non-invasive method to detect real-time cardiac contraction in post-larval (1.1–1.7 mm length), juvenile oysters (i.e., oyster spat) via a fiber-optic trans-illumination system. The system is housed within a temperature-controlled chamber and video microscopy imaging of the heart was coupled with video edge-detection to measure cardiac contraction, inter-beat interval, and heart rate (HR). We used the method to address the hypothesis that cool acclimation (10°C vs. 22°C—Ta10 or Ta22, respectively; each n = 8) would preserve cardiac phenotype (assessed via HR variability, HRV analysis and maintained cardiac activity) during acute temperature changes. The temperature ramp (TR) protocol comprised 2°C steps (10 min/experimental temperature, Texp) from 22°C to 10°C to 22°C. HR was related to Texp in both acclimation groups. Spat became asystolic at low temperatures, particularly Ta22 spat (Ta22: 8/8 vs. Ta10: 3/8 asystolic at Texp = 10°C). The rate of HR decrease during cooling was less in Ta10 vs. Ta22 spat when asystole was included in analysis (P = 0.026). Time-domain HRV was inversely related to temperature and elevated in Ta10 vs. Ta22 spat (P < 0.001), whereas a lack of defined peaks in spectral density precluded frequency-domain analysis. Application of the method during an acute cooling challenge revealed that cool temperature acclimation preserved active cardiac contraction in oyster spat and increased time-domain HRV responses, whereas warm acclimation enhanced asystole. These physiologic changes highlight the need for studies of mechanisms, and have translational potential for oyster aquaculture practices. PMID:27445833

  2. Automated Non-invasive Video-Microscopy of Oyster Spat Heart Rate during Acute Temperature Change: Impact of Acclimation Temperature.

    PubMed

    Domnik, Nicolle J; Polymeropoulos, Elias T; Elliott, Nicholas G; Frappell, Peter B; Fisher, John T

    2016-01-01

    We developed an automated, non-invasive method to detect real-time cardiac contraction in post-larval (1.1-1.7 mm length), juvenile oysters (i.e., oyster spat) via a fiber-optic trans-illumination system. The system is housed within a temperature-controlled chamber and video microscopy imaging of the heart was coupled with video edge-detection to measure cardiac contraction, inter-beat interval, and heart rate (HR). We used the method to address the hypothesis that cool acclimation (10°C vs. 22°C-Ta10 or Ta22, respectively; each n = 8) would preserve cardiac phenotype (assessed via HR variability, HRV analysis and maintained cardiac activity) during acute temperature changes. The temperature ramp (TR) protocol comprised 2°C steps (10 min/experimental temperature, Texp) from 22°C to 10°C to 22°C. HR was related to Texp in both acclimation groups. Spat became asystolic at low temperatures, particularly Ta22 spat (Ta22: 8/8 vs. Ta10: 3/8 asystolic at Texp = 10°C). The rate of HR decrease during cooling was less in Ta10 vs. Ta22 spat when asystole was included in analysis (P = 0.026). Time-domain HRV was inversely related to temperature and elevated in Ta10 vs. Ta22 spat (P < 0.001), whereas a lack of defined peaks in spectral density precluded frequency-domain analysis. Application of the method during an acute cooling challenge revealed that cool temperature acclimation preserved active cardiac contraction in oyster spat and increased time-domain HRV responses, whereas warm acclimation enhanced asystole. These physiologic changes highlight the need for studies of mechanisms, and have translational potential for oyster aquaculture practices.

  3. Estimating Trabecular Bone Mechanical Properties From Non-Invasive Imaging

    NASA Technical Reports Server (NTRS)

    Hogan, Harry A.; Webster, Laurie

    1997-01-01

    An important component in developing countermeasures for maintaining musculoskeletal integrity during long-term space flight is an effective and meaningful method of monitoring skeletal condition. Magnetic resonance imaging (MRI) is an attractive non-invasive approach because it avoids the exposure to radiation associated with X-ray based imaging and also provides measures related to bone microstructure rather than just density. The purpose of the research for the 1996 Summer Faculty Fellowship period was to extend the usefulness of the MRI data to estimate the mechanical properties of trabecular bone. The main mechanical properties of interest are the elastic modulus and ultimate strength. Correlations are being investigated between these and fractal analysis parameters, MRI relaxation times, apparent densities, and bone mineral densities. Bone specimens from both human and equine donors have been studied initially to ensure high-quality MR images. Specimens were prepared and scanned from human proximal tibia bones as well as the equine distal radius. The quality of the images from the human bone appeared compromised due to freezing artifact, so only equine bone was included in subsequent procedures since these specimens could be acquired and imaged fresh before being frozen. MRI scans were made spanning a 3.6 cm length on each of 5 equine distal radius specimens. The images were then sent to Dr. Raj Acharya of the State University of New York at Buffalo for fractal analysis. Each piece was cut into 3 slabs approximately 1.2 cm thick and high-resolution contact radiographs were made to provide images for comparing fractal analysis with MR images. Dual energy X-ray absorptiometry (DEXA) scans were also made of each slab for subsequent bone mineral density determination. Slabs were cut into cubes for mechanical using a slow-speed diamond blade wafering saw (Buehler Isomet). The dimensions and wet weights of each cube specimen were measured and recorded. Wet weights

  4. Post-Traumatic Stress Disorder among Cardiac Patients: Prevalence, Risk Factors, and Considerations for Assessment and Treatment

    PubMed Central

    Tulloch, Heather; Greenman, Paul S.; Tassé, Vanessa

    2014-01-01

    There is increasing awareness of the impact of post-traumatic stress disorder (PTSD) on physical health, particularly cardiovascular disease. We review the literature on the role of trauma in the development of cardiovascular risk factors and disease, aftermath of a cardiac event, and risk for recurrence in cardiac patients. We explore possible mechanisms to explain these relationships, as well as appropriate assessment and treatment strategies for this population. Our main conclusion is that screening and referral for appropriate treatments are important given the high prevalence rates of PTSD in cardiac populations and the associated impact on morbidity and mortality. PMID:25545708

  5. Non-Invasive Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume

    DTIC Science & Technology

    2002-10-01

    Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume PRINCIPAL INVESTIGATOR: Aloyzas Petrikas, Ph.D. Arminas Ragauskas Gediminas...Ultrasonic Diagnosing and Monitoring of DAMD17-00-2-0065 Intracranial Pressure/Volume 6. AUTHOR(S) Aloyzas Petrikas, Ph.D. Arminas Ragauskas Gediminas...Objectives were to verify the innovative concepts of non-invasive intracranial pressure (ICP) absolute value measurement and non- invasive

  6. Biodegradable nano-films for capture and non-invasive release of circulating tumor cells

    PubMed Central

    Park, Myoung-Hwan; Castleberry, Steven; Deng, Jason Z.; Hsu, Bryan; Mayner, Sarah; Jensen, Anne E.; Sequist, Lecia V.; Maheswaran, Shyamala; Haber, Daniel A.; Toner, Mehmet; Stott, Shannon L.; Hammond, Paula T.

    2016-01-01

    Selective isolation and purification of circulating tumor cells (CTCs) from whole blood is an important capability for both clinical medicine and biological research. Current techniques to perform this task place the isolated cells under excessive stresses that reduce cell viability, and potentially induce phenotype change, therefore losing valuable information about the isolated cells. We present a biodegradable nano-film coating on the surface of a microfluidic chip, which can be used to effectively capture as well as non-invasively release cancer cell lines such as PC-3, LNCaP, DU 145, H1650 and H1975. We have applied layer-by-layer (LbL) assembly to create a library of ultrathin coatings using a broad range of materials through complementary interactions. By developing an LbL nano-film coating with an affinity-based cell-capture surface that is capable of selectively isolating cancer cells from whole blood, and that can be rapidly degraded on command, we are able to gently isolate cancer cells and recover them without compromising cell viability or proliferative potential. Our approach has the capability to overcome practical hurdles and provide viable cancer cells for downstream analyses, such as live cell imaging, single cell genomics, and in vitro cell culture of recovered cells. Furthermore, CTCs from cancer patients were also captured, identified, and successfully released using the LbL-modified microchips. PMID:26142780

  7. Spectrophotometric system to develop a non-invasive method for monitoring of posidonia oceanica meadows

    NASA Astrophysics Data System (ADS)

    Menesatti, P.; Urbani, G.; Dolce, T.

    2007-09-01

    Posidonia oceanica (L.) is an endemic phanerogam of the Mediterranean Sea. It lives between 0.2 and 40 m depth and make up extensive meadows that play a fundamental role in the marine coast ecosystem. Near the coasts at higher anthropic pressure, Posidonia meadows present both quality and quantity damages (regression) due to the mechanical operations on the seabed (anchoring, drag netting, pipe lines) and the sea pollution. Nowadays, the seagrass regression is monitored by different systems: aereophotografic, side scan sonar, underwater television camera, direct underwater visual inspection. Scientific community is looking for to develop monitoring systems more reliable, rapid and non invasive. Aim of this study is to evaluate the application of a new spectrophotometric imaging system based on the acquisition of reflectance spectral images with a good optical (250 Kpixels) and spectral resolution (spectral range 400-970 nm, a total of 115 single wavelength, 5 nm step each one). First trials were made on Posidonia's leafs to evaluate the system capacity to recognize spectral differences between samples picked up at two different depths (0.3 - 4 m). High discrimination percentage (90%) were found between leaf samples as function of the different depths, analyzing the spectral data by Partial Least Squares model. Forward activities will stress the system capability also to evaluate different phenol concentrations on Posidonia leaves, an important index of physiologic vegetal damage, through direct underwater spectrophotometric monitoring.

  8. What Do Parents of Children with Down Syndrome Think about Non-Invasive Prenatal Testing (NIPT)?

    PubMed

    van Schendel, Rachèl V; Kater-Kuipers, Adriana; van Vliet-Lachotzki, Elsbeth H; Dondorp, Wybo J; Cornel, Martina C; Henneman, Lidewij

    2016-09-13

    This study explores the attitudes of parents of children with Down syndrome towards non-invasive prenatal testing (NIPT) and widening the scope of prenatal screening. Three focus groups (n = 16) and eleven individual interviews with Dutch parents (and two relatives) of children with Down syndrome were conducted. Safety, accuracy and earlier testing were seen as the advantages of NIPT. Some participants were critical about the practice of screening for Down syndrome, but acknowledged that NIPT enables people to know whether the fetus is affected and to prepare without risking miscarriage. Many feared uncritical use of NIPT and more abortions for Down syndrome. Concerns included the consequences for the acceptance of and facilities for children with Down syndrome, resulting in more people deciding to screen. Participants stressed the importance of good counseling and balanced, accurate information about Down syndrome. Testing for more disorders might divert the focus away from Down syndrome, but participants worried about "where to draw the line". They also feared a loss of diversity in society. Findings show that, while parents acknowledge that NIPT offers a better and safer option to know whether the fetus is affected, they also have concerns about NIPT's impact on the acceptance and care of children with Down syndrome.

  9. Non-invasive monitoring of glucocorticoid metabolites in brown hyaena (Hyaena brunnea) feces.

    PubMed

    Hulsman, A; Dalerum, F; Ganswindt, A; Muenscher, S; Bertschinger, H J; Paris, M

    2011-01-01

    The brown hyaena (Hyaena brunnea) is the least known of the large predators of southern Africa. The current IUCN status of the brown hyaena is "Near Threatened", and there are conservation concerns related to a general lack of biological knowledge of the species. For instance, a better knowledge of the responses to environmental and social stressors would improve our abilities to sustainably manage brown hyaena populations in both captive and free-ranging environments. We conducted adrenocorticotrophic hormone (ACTH) challenges in one female and one male adult brown hyaena at Lion Park Zoo, South Africa, to validate measurements of glucocorticoid metabolites (GCM) in brown hyaena feces via an enzyme immunoassay (EIA). We also measured gastrointestinal transit times (GIT times) and the GCM degradation in feces left in ambient temperature for up to 32 hr to more reliably assess the use of this assay as a tool for non-invasive glucocorticoid measurements. Intramuscular injections of synthetic ACTH yielded GCM levels of 388% (female) and 2,682% (male) above baseline with peak increases occurring 25- to 40-hr after injection. The time delay of fecal GCM excretion approximately corresponded with food transit time in the brown hyaenas. Fecal GCM levels declined significantly over time since defecation. Our results provided a good validation that fecal GCMs accurately reflect circulating glucocorticoid stress hormones in brown hyaenas, but we highlight that samples have to be frozen immediately after defecation to avoid bias in the measurements as a result of bacterial degredation.

  10. Non-invasive measurements of hemoglobin + myoglobin, their oxygenation and NIR light pathlength in heart in vivo by diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Gussakovsky, Eugene; Jilkina, Olga; Yang, Yanmin; Kupriyanov, Valery

    2009-02-01

    The existing non-invasive optical methods of the hemoglobin (Hb) and myoglobin (Mb) estimation in cardiac tissues imply knowledge of the light pathlength (L) when various modifications of Lambert-Beer law for either spectrophotometry or light diffuse reflectance is applied. For Hb and/or Mb quantification in tissue, a few invasive (biochemical) approaches were applied. For L (differential pathlength factor; DPF) determination in tissue, special optical methods were used. No approaches have been proposed to simultaneously and non-invasively determine Hb/Mb and L in cardiac or other muscle tissues. In the present study, the first derivative of the NIR diffuse reflectance spectrum is shown to be effective in simultaneous determination of Hb+Mb concentration (in mM) and L (in mm) in cardiac tissue in vivo. The results showed that measured in a few minutes in a normal pig heart in vivo the total Hb+Mb concentration was 0.9-1.2 mM of heme, tissue oxygen saturation parameter (OSP) was approximately 65%, and DPF at 700-965 nm was of 2.7-2.8. At the experimental ischemia, total [Hb+Mb] decreased by 25%, OSP reduced to zero, while DPF did not change. These results correlated with the previously published. The method may be applied during open-heart surgery, heart studies ex vivo or to any muscle tissue to continuously and non-invasively monitor the [Hb+Mb] content and oxygenation as well as L, which may reflect the changes in tissue structure.

  11. 4-Dimensional light-sheet microscopy to elucidate shear stress modulation of cardiac trabeculation.

    PubMed

    Lee, Juhyun; Fei, Peng; Packard, René R Sevag; Kang, Hanul; Xu, Hao; Baek, Kyung In; Jen, Nelson; Chen, Junjie; Yen, Hilary; Kuo, C-C Jay; Chi, Neil C; Ho, Chih-Ming; Li, Rongsong; Hsiai, Tzung K

    2016-05-02

    Hemodynamic shear forces are intimately linked with cardiac development, during which trabeculae form a network of branching outgrowths from the myocardium. Mutations that alter Notch signaling also result in trabeculation defects. Here, we assessed whether shear stress modulates trabeculation to influence contractile function. Specifically, we acquired 4D (3D + time) images with light sheets by selective plane illumination microscopy (SPIM) for rapid scanning and deep axial penetration during zebrafish morphogenesis. Reduction of blood viscosity via gata1a morpholino oligonucleotides (MO) reduced shear stress, resulting in downregulation of Notch signaling and attenuation of trabeculation. Arrest of cardiomyocyte contraction either by troponin T type 2a (tnnt2a) MO or in weak atriumm58 (wea) mutants resulted in reduced shear stress and downregulation of Notch signaling and trabeculation. Integrating 4D SPIM imaging with synchronization algorithm demonstrated that coinjection of neuregulin1 mRNA with gata1 MO rescued trabeculation to restore contractile function in association with upregulation of Notch-related genes. Crossbreeding of Tg(flk:mCherry) fish, which allows visualization of the vascular system with the Tg(tp1:gfp) Notch reporter line, revealed that shear stress-mediated Notch activation localizes to the endocardium. Deleting endocardium via the clochesk4 mutants downregulated Notch signaling, resulting in nontrabeculated ventricle. Subjecting endothelial cells to pulsatile flow in the presence of the ADAM10 inhibitor corroborated shear stress-activated Notch signaling to modulate trabeculation.

  12. Non-invasive radiofrequency treatment effect on mitochondria in pancreatic cancer cells

    PubMed Central

    Curley, Steven A.; Palalon, Flavio; Lu, Xiaolin; Koshkina, Nadezhda V.

    2015-01-01

    Background Development of novel therapeutic approaches for cancer therapy is important, especially for tumors that have poor response or develop resistance to standard chemotherapy and radiation. We discovered that non-invasive radiofrequency (RF) fields can affect cancer, but not normal cells, inhibit progression of tumors in mice, and enhance anticancer effect of chemotherapy. However, it remains unclear what physiological and molecular mechanisms this treatment induces inside cells. Here, we studied the effect of RF treatment on mitochondria in human pancreatic cancer cells. Methods Morphology of mitochondria in cells was studied by electron microscopy. Alteration of mitochondrial membrane potential (Δψ) was accessed with Mitotracker probe. Respiratory activity of mitochondria was evaluated by changes in oxygen consumption rates (OCR) determined with MitoStress kit. Production of intracellular reactive oxygen species (ROS) was performed using flow cytometry. Colocalization of mitochondria and autophagosome markers in cells was done by fluorescence immunostaining and confocal microscopy analysis. Results RF changed morphology of mitochondria in cancer cells, altered polarization of the mitochondrial membrane, substantially impaired mitochondrial respiration, and increased ROS production, which indicate on the RF-induced stress on mitochondria. We also observed frequent colocalization of the autophagosome marker LC3B with the mitochondrial marker Tom20 inside cancer cells after RF exposure indicating on the presence of mitochondria in the autophagosomes. This suggests that RF-induced stress can damage mitochondria and induce elimination of damaged organelle via autophagy. Conclusion RF treatment impaired the function of mitochondria in cancer cells. Therefore, mitochondria can represent one of the targets of the RF treatment. PMID:24986120

  13. A review on the non-invasive evaluation of skeletal muscle oxygenation

    NASA Astrophysics Data System (ADS)

    Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

    2016-07-01

    The aim of this review is to conduct a feasibility study of non-invasive evaluation in skeletal muscle oxygenation. This non-invasive evaluation could extract many information using a safe non-invasive method regarding to the oxygenation and microcirculation status in human blood muscle. This brief review highlights the progress of the application of NIRS to evaluate skeletal muscle oxygenation in various activity of human nature from the historical point of view to the present advancement. Since the discovery of non-invasive optical method during 1992, there are many non-invasive techniques uses optical properties on human subject such as near infrared spectroscopy NIRS, optical topography, functional near infrared spectroscopy fNIRS and imaging fNIRI. Furthermore, in this paper we discuss the light absorption potential (LAP) towards chromophores content inside human muscle. Modified beer lambert law was studied in order to build a better understanding toward LAP between chromophores under tissue multilayers in human muscle. This paper will describe the NIRS principle and the basis for its proposed used in skeletal muscle oxygenation. This will cover the advantages and limitation of such application. Thus, these non-invasive techniques could open other possibilities to study muscle performance diagnosis.

  14. Mechanical stress-strain sensors embedded in cardiac cytoskeleton: Z disk, titin, and associated structures

    PubMed Central

    Hoshijima, Masahiko

    2011-01-01

    Cardiac muscle is equipped with intricate intrinsic mechanisms to regulate adaptive remodeling. Recent and extensive experimental findings powered by novel strategies for screening protein-protein interactions, improved imaging technologies, and versatile transgenic mouse methodologies reveal that Z disks and titin filaments possess unexpectedly complicated sensory and modulatory mechanisms for signal reception and transduction. These mechanisms employ molecules such as muscle-enriched LIM domain proteins, PDZ-LIM domain proteins, myozenin gene family members, titin-associated ankyrin repeat family proteins, and muscle-specific ring finger proteins, which have been identified as potential molecular sensor components. Moreover, classic transmembrane signaling processes, including mitogen-activated kinase, protein kinase C, and calcium signaling, also involve novel interactions with the Z disk/titin network. This compartmentalization of signaling complexes permits alteration of receptor-dependent transcriptional regulation by direct sensing of intrinsic stress. Newly identified mechanical stress sensors are not limited to Z-disk region and to I-band and M-band regions of titin but are also embedded in muscle-specific membrane systems such as the costamere, intercalated disks, and caveolae-like microdomains. This review summarizes current knowledge of this rapidly developing area with focus on how the heart adjusts physiological remodeling process to meet with mechanical demands and how this process fails in cardiac pathologies. PMID:16537787

  15. Monitoring Non-Invasive Cardiac Output and Stroke Volume during Experimental Human Hypovolaemia and Resuscitation

    DTIC Science & Technology

    2011-01-01

    Methods. Healthy human subjects (n¼21) underwent central hypovolaemia through progressive lower body negative pressure (LBNP) until the onset of presyncope...lower body negative pressure (LBNP), a well-established experimental model of central hypovolaemia.15 We assessed how well the investiga- tional methods...JJ, Schreuder JJ. Computation of aortic flow from pressure in humans using a nonlinear, three-element model. J Appl Physiol 1993; 74: 2566–73 8

  16. Non-invasive diagnostic and functional evaluation of cardiac involvement in patients with systemic sclerosis.

    PubMed

    Ciurzyński, Michał; Bienias, Piotr; Lichodziejewska, Barbara; Kurnicka, Katarzyna; Szewczyk, Agnieszka; Glińska-Wielochowska, Maria; Kurzyna, Marcin; Błaszczyk, Maria; Liszewska-Pfejfer, Danuta; Pruszczyk, Piotr

    2008-08-01

    Elevated serum brain natriuretic peptide (BNP) released from myocytes of ventricles upon stretch have been found in patients with isolated right ventricular (RV) pressure overload. However, limited data suggest that serum BNP may be elevated in systemic sclerosis (SSc) patients, especially with RV dysfunction. We assessed serum N-terminal proBNP (NT-proBNP) in SSc and evaluated whether it reflects the severity of RV overload. We prospectively studied 51 consecutive patients (47F, mean age 53.3 +/- 15.2 years) with SSc (mean disease duration 9 +/- 12.4 years). The control group formed 31 healthy subjects (27F, mean age 52.6 +/- 12.1 years). NT-proBNP level, 6-minute walking test (6MWT), and transthoracic echocardiography (TTE) for the assessment of RV overload were performed. Serum NT-proBNP exceeded the reference value of 125 pg/mL in 31 (61%) SSc patients. The mean serum log NT-proBNP concentration in SSc was higher than in controls (2.138 +/- 0.527 vs. 1.634 +/- 0.420 pg/mL, p < 0.001). 13 (25%) SSc patients have tricuspid regurgitation peak gradient (TRPG) exceeding 31 mmHg reflecting pulmonary arterial hypertension (PAH). The SSc presented other echocardiographic signs of RV overload. Mean 6MWT distance was shorter in SSc than in controls (528 +/- 100 vs. 617 +/- 80 m, p < 0.001). NT-proBNP level correlated positively with TRPG, RV diameter, RV Tei index and negatively with 6MWT distance. ROC analysis identified >115 pg/ml as the best NT-proBNP threshold predicting PAH for SSc patients (sensitivity 92%, specificity 44%). Results of our study suggest that NT-proBNP measurement is a useful screening method for PAH in SSc patients. Since elevated plasma NT-proBNP level reflects the degree of right ventricular overload and limitation of exercise capacity, abnormal NT-proBNP levels should imply further evaluation including echocardiography.

  17. (Non-invasive evaluation of the cardiac autonomic nervous system by PET)

    SciTech Connect

    Not Available

    1991-01-01

    Our research efforts in the first funding year concentrated on animal and clinical studies validating {sup 11}C-hydroxyephedrine as a marker for norepinephrine uptake and storage in presynaptic sympathetic nerve terminals. In addition to kinetic studies in animals, the first clinical studies have been performed. {sup 11}C-hydroxyephedrine provides excellent image quality in the human heart with high myocardium to blood ratios. A canine model with transient intracoronary occlusion of the left anterior descending aorta was used to show decreased retention of tracer with ischemia. Clinical studies of patients with acute myocardial infarction showed an area of decreased retention of tracer exceeding the infarct territory as defined by {sup 82}Rb blood flow imaging. We are also developing tracers for the parasympathetic nervous system. It appears that methyl-TRB is a specific tracer for this system. Studies of {sup 11}C- or {sup 18}F-benzovesamicol as a potential tracer for parasympathetic presynaptic nerve terminals are under way. (MHB)

  18. Non-invasive evaluation of culprit lesions by PET imaging: shifting the clinical paradigm away from resultant anatomy toward causative physiology.

    PubMed

    Caobelli, Federico; Bengel, Frank M

    2014-12-01

    Although coronary angiography is the gold standard for assessing coronary artery disease (CAD), there is at best a weak correlation between degree of stenosis and the risk of developing cardiac events. Plaque rupture is the most common type of plaque complication, accounting for about 70% of fatal acute myocardial infarctions or sudden coronary deaths. Recently, the feasibility of (18)F-fluoride PET/CT in the evaluation of atherosclerotic lesions was assessed. Radionuclide techniques allow non-invasive biologic assessment of atherosclerotic plaques. This may help to further shift the clinical paradigm in coronary disease away from anatomy toward causative physiology and biology.

  19. Non-invasive evaluation of culprit lesions by PET imaging: shifting the clinical paradigm away from resultant anatomy toward causative physiology

    PubMed Central

    Bengel, Frank M.

    2014-01-01

    Although coronary angiography is the gold standard for assessing coronary artery disease (CAD), there is at best a weak correlation between degree of stenosis and the risk of developing cardiac events. Plaque rupture is the most common type of plaque complication, accounting for about 70% of fatal acute myocardial infarctions or sudden coronary deaths. Recently, the feasibility of 18F-fluoride PET/CT in the evaluation of atherosclerotic lesions was assessed. Radionuclide techniques allow non-invasive biologic assessment of atherosclerotic plaques. This may help to further shift the clinical paradigm in coronary disease away from anatomy toward causative physiology and biology. PMID:25610799

  20. Cardiac output after burn injury.

    PubMed Central

    Porter, J. M.; Shakespeare, P. G.

    1984-01-01

    Cardiac output after burn injury has been measured by the non-invasive method of impedance plethysmography. An initial study of 143 normal subjects was undertaken in order to investigate variations in cardiac output with age. Fifteen patients were monitored during resuscitation after extensive burns. Fourteen patients showed a depression of stroke volume below the lower limits of the normal range, derived from the initial study on normal people. PMID:6691694

  1. Capacitive Sensing for Non-Invasive Breathing and Heart Monitoring in Non-Restrained, Non-Sedated Laboratory Mice.

    PubMed

    González-Sánchez, Carlos; Fraile, Juan-Carlos; Pérez-Turiel, Javier; Damm, Ellen; Schneider, Jochen G; Zimmermann, Heiko; Schmitt, Daniel; Ihmig, Frank R

    2016-07-07

    Animal testing plays a vital role in biomedical research. Stress reduction is important for improving research results and increasing the welfare and the quality of life of laboratory animals. To estimate stress we believe it is of great importance to develop non-invasive techniques for monitoring physiological signals during the transport of laboratory animals, thereby allowing the gathering of information on the transport conditions, and, eventually, the improvement of these conditions. Here, we study the suitability of commercially available electric potential integrated circuit (EPIC) sensors, using both contact and contactless techniques, for monitoring the heart rate and breathing rate of non-restrained, non-sedated laboratory mice. The design has been tested under different scenarios with the aim of checking the plausibility of performing contactless capture of mouse heart activity (ideally with an electrocardiogram). First experimental results are shown.

  2. Capacitive Sensing for Non-Invasive Breathing and Heart Monitoring in Non-Restrained, Non-Sedated Laboratory Mice

    PubMed Central

    González-Sánchez, Carlos; Fraile, Juan-Carlos; Pérez-Turiel, Javier; Damm, Ellen; Schneider, Jochen G.; Zimmermann, Heiko; Schmitt, Daniel; Ihmig, Frank R.

    2016-01-01

    Animal testing plays a vital role in biomedical research. Stress reduction is important for improving research results and increasing the welfare and the quality of life of laboratory animals. To estimate stress we believe it is of great importance to develop non-invasive techniques for monitoring physiological signals during the transport of laboratory animals, thereby allowing the gathering of information on the transport conditions, and, eventually, the improvement of these conditions. Here, we study the suitability of commercially available electric potential integrated circuit (EPIC) sensors, using both contact and contactless techniques, for monitoring the heart rate and breathing rate of non-restrained, non-sedated laboratory mice. The design has been tested under different scenarios with the aim of checking the plausibility of performing contactless capture of mouse heart activity (ideally with an electrocardiogram). First experimental results are shown. PMID:27399713

  3. Invasive hemodynamics of constrictive pericarditis, restrictive cardiomyopathy, and cardiac tamponade.

    PubMed

    Sorajja, Paul

    2011-05-01

    Cardiac catheterization historically has been the principal diagnostic modality for the evaluation of constrictive pericarditis, restrictive cardiomyopathy, and cardiac tamponade. In many instances, the hemodynamic consequences of these disorders can be accurately delineated with non-invasive methods. However, cardiac catheterization should be considered when there is a discrepancy between the clinical and non-invasive imaging data, and particularly may be required for the evaluation of patients with complex hemodynamic disorders. This report describes the methods and clinical utility of invasive hemodynamic catheterization for the evaluation of constriction, restriction, and cardiac tamponade.

  4. HACE1-dependent protein degradation provides cardiac protection in response to haemodynamic stress

    NASA Astrophysics Data System (ADS)

    Zhang, Liyong; Chen, Xin; Sharma, Parveen; Moon, Mark; Sheftel, Alex D.; Dawood, Fayez; Nghiem, Mai P.; Wu, Jun; Li, Ren-Ke; Gramolini, Anthony O.; Sorensen, Poul H.; Penninger, Josef M.; Brumell, John H.; Liu, Peter P.

    2014-03-01

    The HECT E3 ubiquitin ligase HACE1 is a tumour suppressor known to regulate Rac1 activity under stress conditions. HACE1 is increased in the serum of patients with heart failure. Here we show that HACE1 protects the heart under pressure stress by controlling protein degradation. Hace1 deficiency in mice results in accelerated heart failure and increased mortality under haemodynamic stress. Hearts from Hace1-/- mice display abnormal cardiac hypertrophy, left ventricular dysfunction, accumulation of LC3, p62 and ubiquitinated proteins enriched for cytoskeletal species, indicating impaired autophagy. Our data suggest that HACE1 mediates p62-dependent selective autophagic turnover of ubiquitinated proteins by its ankyrin repeat domain through protein-protein interaction, which is independent of its E3 ligase activity. This would classify HACE1 as a dual-function E3 ligase. Our finding that HACE1 has a protective function in the heart in response to haemodynamic stress suggests that HACE1 may be a potential diagnostic and therapeutic target for heart disease.

  5. Cannabinoid 1 receptor promotes cardiac dysfunction, oxidative stress, inflammation, and fibrosis in diabetic cardiomyopathy.

    PubMed

    Rajesh, Mohanraj; Bátkai, Sándor; Kechrid, Malek; Mukhopadhyay, Partha; Lee, Wen-Shin; Horváth, Béla; Holovac, Eileen; Cinar, Resat; Liaudet, Lucas; Mackie, Ken; Haskó, György; Pacher, Pál

    2012-03-01

    Endocannabinoids and cannabinoid 1 (CB(1)) receptors have been implicated in cardiac dysfunction, inflammation, and cell death associated with various forms of shock, heart failure, and atherosclerosis, in addition to their recognized role in the development of various cardiovascular risk factors in obesity/metabolic syndrome and diabetes. In this study, we explored the role of CB(1) receptors in myocardial dysfunction, inflammation, oxidative/nitrative stress, cell death, and interrelated signaling pathways, using a mouse model of type 1 diabetic cardiomyopathy. Diabetic cardiomyopathy was characterized by increased myocardial endocannabinoid anandamide levels, oxidative/nitrative stress, activation of p38/Jun NH(2)-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs), enhanced inflammation (tumor necrosis factor-α, interleukin-1β, cyclooxygenase 2, intracellular adhesion molecule 1, and vascular cell adhesion molecule 1), increased expression of CB(1), advanced glycation end product (AGE) and angiotensin II type 1 receptors (receptor for advanced glycation end product [RAGE], angiotensin II receptor type 1 [AT(1)R]), p47(phox) NADPH oxidase subunit, β-myosin heavy chain isozyme switch, accumulation of AGE, fibrosis, and decreased expression of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA2a). Pharmacological inhibition or genetic deletion of CB(1) receptors attenuated the diabetes-induced cardiac dysfunction and the above-mentioned pathological alterations. Activation of CB(1) receptors by endocannabinoids may play an important role in the pathogenesis of diabetic cardiomyopathy by facilitating MAPK activation, AT(1)R expression/signaling, AGE accumulation, oxidative/nitrative stress, inflammation, and fibrosis. Conversely, CB(1) receptor inhibition may be beneficial in the treatment of diabetic cardiovascular complications.

  6. Physical Stress Echocardiography: Prediction of Mortality and Cardiac Events in Patients with Exercise Test showing Ischemia.

    PubMed

    Araujo, Ana Carla Pereira de; Santos, Bruno F de Oliveira; Calasans, Flavia Ricci; Pinto, Ibraim M Francisco; Oliveira, Daniel Pio de; Melo, Luiza Dantas; Andrade, Stephanie Macedo; Tavares, Irlaneide da Silva; Sousa, Antonio Carlos Sobral; Oliveira, Joselina Luzia Menezes

    2014-11-01

    Background: Studies have demonstrated the diagnostic accuracy and prognostic value of physical stress echocardiography in coronary artery disease. However, the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia is limited. Objective: To evaluate the effectiveness of physical stress echocardiography in the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia. Methods: This is a retrospective cohort in which 866 consecutive patients with exercise test positive for myocardial ischemia, and who underwent physical stress echocardiography were studied. Patients were divided into two groups: with physical stress echocardiography negative (G1) or positive (G2) for myocardial ischemia. The endpoints analyzed were all-cause mortality and major cardiac events, defined as cardiac death and non-fatal acute myocardial infarction. Results: G2 comprised 205 patients (23.7%). During the mean 85.6 ± 15.0-month follow-up, there were 26 deaths, of which six were cardiac deaths, and 25 non-fatal myocardial infarction cases. The independent predictors of mortality were: age, diabetes mellitus, and positive physical stress echocardiography (hazard ratio: 2.69; 95% confidence interval: 1.20 - 6.01; p = 0.016). The independent predictors of major cardiac events were: age, previous coronary artery disease, positive physical stress echocardiography (hazard ratio: 2.75; 95% confidence interval: 1.15 - 6.53; p = 0.022) and absence of a 10% increase in ejection fraction. All-cause mortality and the incidence of major cardiac events were significantly higher in G2 (p < 0. 001 and p = 0.001, respectively). Conclusion: Physical stress echocardiography provides additional prognostic information in patients with exercise test positive for myocardial ischemia.Fundamento: Estudos têm demonstrado a acurácia diagnóstica e o valor prognóstico da ecocardiografia com estresse f

  7. Non-Invasive Ventilation in Patients with Heart Failure: A Systematic Review and Meta-Analysis.

    PubMed

    Bittencourt, Hugo Souza; Reis, Helena França Correia Dos; Lima, Melissa Santos; Gomes, Mansueto

    2017-02-01

    Non-invasive ventilation (NIV) may perfect respiratory and cardiac performance in patients with heart failure (HF). The objective of the study to establish, through systematic review and meta-analysis, NIV influence on functional capacity of HF patients. A systematic review with meta-analysis of randomized studies was carried out through research of databases of Cochrane Library, SciELO, Pubmed and PEDro, using the key-words: heart failure, non-invasive ventilation, exercise tolerance; and the free terms: bi-level positive airway pressure (BIPAP), continuous positive airway pressure (CPAP), and functional capacity (terms were searched for in English and Portuguese) using the Boolean operators AND and OR. Methodological quality was ensured through PEDro scale. Weighted averages and a 95% confidence interval (CI) were calculated. The meta-analysis was done thorugh the software Review Manager, version 5.3 (Cochrane Collaboration). Four randomized clinical trials were included. Individual studies suggest NIV improved functional capacity. NIV resulted in improvement in the distance of the six-minute walk test (6MWT) (68.7m 95%CI: 52.6 to 84.9) in comparison to the control group. We conclude that the NIV is an intervention that promotes important effects in the improvement of functional capacity of HF patients. However, there is a gap in literature on which are the most adequate parameters for the application of this technique. Resumo A ventilação não invasiva (VNI) pode aperfeiçoar o desempenho cardíaco e respiratório dos pacientes com insuficiência cardíaca (IC). O objetivo do estudo é estabelecer, por meio de revisão sistemática e meta-análise, a influência da VNI na capacidade funcional (CF) de indivíduos com IC. Foi realizada uma revisão sistemática com meta-análise de estudos randomizados através da pesquisa nas bases de dados Biblioteca Cochrane, SciELO, Pubmed e PEDro, utilizando-se as palavras-chave: insuficiência cardíaca, ventilação n

  8. Cost analysis of non-invasive fractional flow reserve derived from coronary computed tomographic angiography in Japan.

    PubMed

    Kimura, Takeshi; Shiomi, Hiroki; Kuribayashi, Sachio; Isshiki, Takaaki; Kanazawa, Susumu; Ito, Hiroshi; Ikeda, Shunya; Forrest, Ben; Zarins, Christopher K; Hlatky, Mark A; Norgaard, Bjarne L

    2015-01-01

    Percutaneous coronary intervention (PCI) based on fractional flow reserve (FFRcath) measurement during invasive coronary angiography (CAG) results in improved patient outcome and reduced healthcare costs. FFR can now be computed non-invasively from standard coronary CT angiography (cCTA) scans (FFRCT). The purpose of this study is to determine the potential impact of non-invasive FFRCT on costs and clinical outcomes of patients with suspected coronary artery disease in Japan. Clinical data from 254 patients in the HeartFlowNXT trial, costs of goods and services in Japan, and clinical outcome data from the literature were used to estimate the costs and outcomes of 4 clinical pathways: (1) CAG-visual guided PCI, (2) CAG-FFRcath guided PCI, (3) cCTA followed by CAG-visual guided PCI, (4) cCTA-FFRCT guided PCI. The CAG-visual strategy demonstrated the highest projected cost ($10,360) and highest projected 1-year death/myocardial infarction rate (2.4 %). An assumed price for FFRCT of US $2,000 produced equivalent clinical outcomes (death/MI rate: 1.9 %) and healthcare costs ($7,222) for the cCTA-FFRCT strategy and the CAG-FFRcath guided PCI strategy. Use of the cCTA-FFRCT strategy to select patients for PCI would result in 32 % lower costs and 19 % fewer cardiac events at 1 year compared to the most commonly used CAG-visual strategy. Use of cCTA-FFRCT to select patients for CAG and PCI may reduce costs and improve clinical outcome in patients with suspected coronary artery disease in Japan.

  9. Restraint stress exacerbates cardiac and adipose tissue pathology via β-adrenergic signaling in rats with metabolic syndrome.

    PubMed

    Matsuura, Natsumi; Nagasawa, Kai; Minagawa, Yuji; Ito, Shogo; Sano, Yusuke; Yamada, Yuichiro; Hattori, Takuya; Watanabe, Shogo; Murohara, Toyoaki; Nagata, Kohzo

    2015-05-15

    Restraint stress stimulates sympathetic nerve activity and can affect adiposity and metabolism. However, the effects of restraint stress on cardiovascular and metabolic disorders in metabolic syndrome (MetS) have remained unclear. We investigated the effects of chronic restraint stress and β-adrenergic receptor (β-AR) blockade on cardiac and adipose tissue pathology and metabolic disorders in a rat model of MetS. DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats. Rats were exposed to restraint stress (restraint cage, 2 h/day) for 4 wk from 9 wk of age with or without daily subcutaneous administration of the β-AR blocker propranolol (2 mg/kg). Age-matched homozygous lean littermates of DS/obese rats (DahlS.Z-Lepr(+)/Lepr(+) rats) served as control animals. Chronic restraint stress exacerbated hypertension as well as left ventricular hypertrophy, fibrosis, diastolic dysfunction, and oxidative stress in a manner sensitive to propranolol treatment. Restraint stress attenuated body weight gain in DS/obese rats, and this effect tended to be reversed by propranolol (P = 0.0682). Restraint stress or propranolol did not affect visceral or subcutaneous fat mass. However, restraint stress potentiated cardiac and visceral adipose tissue inflammation in DS/obese rats, and these effects were ameliorated by propranolol. Restraint stress also exacerbated glucose intolerance, insulin resistance, and abnormal lipid metabolism in a manner sensitive to propranolol. In addition, restraint stress increased urinary norepinephrine excretion, and propranolol attenuated this effect. Our results thus implicate β-ARs in the exacerbation of cardiac and adipose tissue pathology and abnormal glucose and lipid metabolism induced by restraint stress in this model of MetS.

  10. Non-Invasive Measurement of Pulsatile Intracranial Pressures Using Ultrasound

    NASA Technical Reports Server (NTRS)

    Ueno, Toshiaki; Ballard, Richard E.; Shuer, Lawrence M.; Cantrell, John H.; Cantrell, John H.; Hargens, Alan R.

    1997-01-01

    Early detection of elevated intracranial pressure (ICP) will aid clinical decision-making for head trauma, brain tumor and other cerebrovascular diseases. Conventional methods, however, require surgical procedures which take time and are accompanied by increased risk of infection. Accordingly we have developed and refined a new ultrasound device to measure skull movements which are known to occur in conjunction with altered ICP. The principle of this device is based upon pulse phase locked loop (PPLL), which enables us to detect changes in distance on the order of microns between an ultrasound transducer on one side of the skull and the opposite inner surface of the cranium. The present study was designed to verify this measurement technique in cadavera. Transcranial distance was increased in steps of 10 mmHg from zero to 50 mmHg by saline infusion into the lateral ventricle of two cadavera. In separate experiments, pulsations of ICP with the amplitudes of zero to 2 mmHg were generated by rhythmic injections of saline using a syringe. When the ICP was stepwise increased from zero to 50 mmHg, transcranial distance increased in proportion with the ICP increase (y=12 x - 76, r=0.938), where y is changes in transcranial distance in microns and x is ICP in mmHg. In the data recorded while ICP pulsations were generated, fast Fourier transform analysis demonstrated that cranial pulsations were clearly associated with ICP pulsations. The results indicate that changes in transcranial distance is linearly correlated with those in ICP, and also that the PPLL device has sufficient sensitivity to detect transcranial pulsations which occur in association with the cardiac cycle. By analyzing the magnitude of cranial pulsations, we may be able to estimate the pressure-volume index in the cranium. As a result, estimates of intracranial compliance may be possible by using the PPLL device. Further studies are necessary in normal subjects and patients.

  11. Shear Stress, Energy Losses, and Costs: A Resolved Dilemma of Pulsatile Cardiac Assist Devices

    PubMed Central

    Liu, Jia; Dai, Gang; Carbognani, Daniel; Yang, Daya; Wu, Guifu; Wang, Qinmei; Chachques, Juan Carlos

    2014-01-01

    Cardiac assist devices (CAD) cause endothelial dysfunction with considerable morbidity. Employment of pulsatile CAD remains controversial due to inadequate perfusion curves and costs. Alternatively, we are proposing a new concept of pulsatile CAD based on a fundamental revision of the entire circulatory system in correspondence with the physiopathology and law of physics. It concerns a double lumen disposable tube device that could be adapted to conventional cardiopulmonary bypass (CPB) and/or CAD, for inducing a homogenous, downstream pulsatile perfusion mode with lower energy losses. In this study, the device's prototypes were tested in a simulated conventional pediatric CPB circuit for energy losses and as a left ventricular assist device (LVAD) in ischemic piglets model for endothelial shear stress (ESS) evaluations. In conclusion and according to the study results the pulsatile tube was successfully capable of transforming a conventional CPB and/or CAD steady flow into a pulsatile perfusion mode, with nearly physiologic pulse pressure and lower energy losses. This represents a cost-effective promising method with low mortality and morbidity, especially in fragile cardiac patients. PMID:24511541

  12. Decreased Cardiac Vagal Control in Drug-Naïve Patients with Posttraumatic Stress Disorder

    PubMed Central

    Chang, Hsin-An; Chang, Chuan-Chia; Tzeng, Nian-Sheng; Kuo, Terry BJ; Lu, Ru-Band

    2013-01-01

    Objective Decreased cardiac vagal control (CVC) has been proposed in posttraumatic stress disorder (PTSD), but the results are mixed. Analyses with larger sample sizes and better methodology are needed. Methods Thirty-two drug-naïve survivors with current PTSD, 32 survivors without PTSD and 192 matched controls were recruited for a case-control analysis. We used the PTSD checklist-civilian version (PCL-C) to assess posttraumatic symptoms severity. Cardiac autonomic function was evaluated by measuring heart rate variability (HRV) parameters. Frequency-domain indices of HRV were obtained. The obtained results were evaluated in association with personality traits assessed by the Tridimensional Personality Questionnaire (TPQ). Results PTSD patients exhibited decreased LF-HRV and HF-HRV as compared to survivors without PTSD and to matched controls. The PTSD symptoms severity was associated with reduced mean RR intervals, Var-HRV, LF-HRV and HF-HRV. The harm avoidance score (which has been suggested to be associated with serotonergic activity) was negatively correlated with Var-HRV, LF-HRV and HF-HRV. Conclusion These data suggest that PTSD is accompanied by decreased CVC, highlighting the importance of assessing HRV in PTSD patients. In view of the increased risk for cardiovascular diseases in these vulnerable individuals, one might consider the treatment to restore their autonomic function while reducing PTSD symptoms. PMID:23798959

  13. Differential effects of hypoxic and hyperoxic stress-induced hypertrophy in cultured chick fetal cardiac myocytes.

    PubMed

    Greco, Allison A; Gomez, George

    2014-02-01

    The adult heart responds to contraction demands by hypertrophy, or enlargement, of cardiac myocytes. Adaptive hypertrophy can occur in response to hyperoxic conditions such as exercise, while pathological factors that result in hypoxia ultimately result in heart failure. The difference in the outcomes produced by pathologically versus physiologically induced hypertrophy suggests that the cellular signaling pathways or conditions of myocytes may be different at the cellular level. The structural and functional changes in myocytes resulting from hyperoxia (simulated using hydrogen peroxide) and hypoxia (using oxygen deprivation) were tested on fetal chick cardiac myocytes grown in vitro. Structural changes were measured using immunostaining for α-sarcomeric actin or MyoD, while functional changes were assessed using immunostaining for calcium/calmodulin-dependent kinase (CaMKII) and by measuring intracellular calcium fluxes using live cell fluorescence imaging. Both hypoxic and hyperoxic stress resulted in an upregulation of actin and MyoD expression. Similarly, voltage-gated channels governing myocyte depolarization and the regulation of CaMK were unchanged by hyperoxic or hypoxic conditions. However, the dynamic features of calcium fluxes elicited by caffeine or epinephrine were different in cells subjected to hypoxia versus hyperoxia, suggesting that these different conditions differentially affect components of ligand-activated signaling pathways that regulate calcium. Our results suggest that changes in signaling pathways, rather than structural organization, may mediate the different outcomes associated with hyperoxia-induced versus hypoxia-induced hypertrophy, and these changes are likely initiated at the cellular level.

  14. 4-Dimensional light-sheet microscopy to elucidate shear stress modulation of cardiac trabeculation

    PubMed Central

    Lee, Juhyun; Fei, Peng; Packard, René R. Sevag; Kang, Hanul; Xu, Hao; Baek, Kyung In; Jen, Nelson; Chen, Junjie; Yen, Hilary; Chi, Neil C.; Ho, Chih-Ming; Hsiai, Tzung K.

    2016-01-01

    Hemodynamic shear forces are intimately linked with cardiac development, during which trabeculae form a network of branching outgrowths from the myocardium. Mutations that alter Notch signaling also result in trabeculation defects. Here, we assessed whether shear stress modulates trabeculation to influence contractile function. Specifically, we acquired 4D (3D + time) images with light sheets by selective plane illumination microscopy (SPIM) for rapid scanning and deep axial penetration during zebrafish morphogenesis. Reduction of blood viscosity via gata1a morpholino oligonucleotides (MO) reduced shear stress, resulting in downregulation of Notch signaling and attenuation of trabeculation. Arrest of cardiomyocyte contraction either by troponin T type 2a (tnnt2a) MO or in weak atriumm58 (wea) mutants resulted in reduced shear stress and downregulation of Notch signaling and trabeculation. Integrating 4D SPIM imaging with synchronization algorithm demonstrated that coinjection of neuregulin1 mRNA with gata1 MO rescued trabeculation to restore contractile function in association with upregulation of Notch-related genes. Crossbreeding of Tg(flk:mCherry) fish, which allows visualization of the vascular system with the Tg(tp1:gfp) Notch reporter line, revealed that shear stress–mediated Notch activation localizes to the endocardium. Deleting endocardium via the clochesk4 mutants downregulated Notch signaling, resulting in nontrabeculated ventricle. Subjecting endothelial cells to pulsatile flow in the presence of the ADAM10 inhibitor corroborated shear stress–activated Notch signaling to modulate trabeculation. PMID:27018592

  15. Stress Cardiac Magnetic Resonance Imaging With Observation Unit Care Reduces Cost for Patients With Emergent Chest Pain: A Randomized Trial

    PubMed Central

    Miller, Chadwick D.; Hwang, Wenke; Hoekstra, James W.; Case, Doug; Lefebvre, Cedric; Blumstein, Howard; Hiestand, Brian; Diercks, Deborah B.; Hamilton, Craig A.; Harper, Erin N.; Hundley, W. Gregory

    2013-01-01

    Study objective We determine whether imaging with cardiac magnetic resonance imaging (MRI) in an observation unit would reduce medical costs among patients with emergent non-low-risk chest pain who otherwise would be managed with an inpatient care strategy. Methods Emergency department patients (n=110) at intermediate or high probability for acute coronary syndrome without electrocardiographic or biomarker evidence of a myocardial infarction provided consent and were randomized to stress cardiac MRI in an observation unit versus standard inpatient care. The primary outcome was direct hospital cost calculated as the sum of hospital and provider costs. Estimated median cost differences (Hodges-Lehmann) and distribution-free 95% confidence intervals (Moses) were used to compare groups. Results There were 110 participants with 53 randomized to cardiac MRI and 57 to inpatient care; 8 of 110 (7%) experienced acute coronary syndrome. In the MRI pathway, 49 of 53 underwent stress cardiac MRI, 11 of 53 were admitted, 1 left against medical advice, 41 were discharged, and 2 had acute coronary syndrome. In the inpatient care pathway, 39 of 57 patients initially received stress testing, 54 of 57 were admitted, 3 left against medical advice, and 6 had acute coronary syndrome. At 30 days, no subjects in either group experienced acute coronary syndrome after discharge. The cardiac MRI group had a reduced median hospitalization cost (Hodges-Lehmann estimate $588; 95% confidence interval $336 to $811); 79% were managed without hospital admission. Conclusion Compared with inpatient care, an observation unit strategy involving stress cardiac MRI reduced incident cost without any cases of missed acute coronary syndrome in patients with emergent chest pain. PMID:20554078

  16. Binge Ethanol and MDMA Combination Exacerbates Toxic Cardiac Effects by Inducing Cellular Stress

    PubMed Central

    Navarro-Zaragoza, Javier; Ros-Simó, Clara; Milanés, María-Victoria; Valverde, Olga; Laorden, María-Luisa

    2015-01-01

    Binge drinking is a common pattern of ethanol consumption among young people. Binge drinkers are especially susceptible to brain damage when other substances are co-administered, in particular 3,4 methylendioxymethamphetamine (MDMA). The aim of the present work was to study the mechanisms implicated in the adaptive changes observed after administration of these drugs of abuse. So, we have evaluated the cardiac sympathetic activity and the expression and activation of heat shock protein 27 (HSP27), after voluntary binge ethanol consumption, alone and in combination with MDMA. Both parameters are markers of stressful situations and they could be modified inducing several alterations in different systems. Adolescent mice received MDMA, ethanol or both (ethanol plus MDMA). Drinking in the dark (DID) procedure was used as a model of binge. Noradrenaline (NA) turnover, tyrosine hydroxylase (TH), TH phosphorylated at serine 31 and HSP27 expression and its phosphorylation at serine 82 were evaluated in adolescent mice 48 h, 72 h, and 7 days after treatments in the left ventricle. NA and normetanephrine (NMN) were determined by high-performance liquid chromatography (HPLC); TH and HSP27 expression and phosphorylation were measured by quantitative blot immunollabeling using specific antibodies. Ethanol and MDMA co-administration increased NA turnover and TH expression and phosphorylation versus the consumption of each one of these drugs. In parallel with the described modifications in the cardiac sympathetic activity, our results showed that binge ethanol+MDMA exposure is associated with an increase in HSP27 expression and phosphorylation in the left ventricle, supporting the idea that the combination of both drugs exacerbates the cellular stress induced by ethanol or MDMA alone. PMID:26509576

  17. Binge Ethanol and MDMA Combination Exacerbates Toxic Cardiac Effects by Inducing Cellular Stress.

    PubMed

    Navarro-Zaragoza, Javier; Ros-Simó, Clara; Milanés, María-Victoria; Valverde, Olga; Laorden, María-Luisa

    2015-01-01

    Binge drinking is a common pattern of ethanol consumption among young people. Binge drinkers are especially susceptible to brain damage when other substances are co-administered, in particular 3,4 methylendioxymethamphetamine (MDMA). The aim of the present work was to study the mechanisms implicated in the adaptive changes observed after administration of these drugs of abuse. So, we have evaluated the cardiac sympathetic activity and the expression and activation of heat shock protein 27 (HSP27), after voluntary binge ethanol consumption, alone and in combination with MDMA. Both parameters are markers of stressful situations and they could be modified inducing several alterations in different systems. Adolescent mice received MDMA, ethanol or both (ethanol plus MDMA). Drinking in the dark (DID) procedure was used as a model of binge. Noradrenaline (NA) turnover, tyrosine hydroxylase (TH), TH phosphorylated at serine 31 and HSP27 expression and its phosphorylation at serine 82 were evaluated in adolescent mice 48 h, 72 h, and 7 days after treatments in the left ventricle. NA and normetanephrine (NMN) were determined by high-performance liquid chromatography (HPLC); TH and HSP27 expression and phosphorylation were measured by quantitative blot immunollabeling using specific antibodies. Ethanol and MDMA co-administration increased NA turnover and TH expression and phosphorylation versus the consumption of each one of these drugs. In parallel with the described modifications in the cardiac sympathetic activity, our results showed that binge ethanol+MDMA exposure is associated with an increase in HSP27 expression and phosphorylation in the left ventricle, supporting the idea that the combination of both drugs exacerbates the cellular stress induced by ethanol or MDMA alone.

  18. Secoisolariciresinol diglucoside attenuates cardiac hypertrophy and oxidative stress in monocrotaline-induced right heart dysfunction.

    PubMed

    Puukila, Stephanie; Fernandes, Rafael Oliveira; Türck, Patrick; Carraro, Cristina Campos; Bonetto, Jéssica Hellen Poletto; de Lima-Seolin, Bruna Gazzi; da Rosa Araujo, Alex Sander; Belló-Klein, Adriane; Boreham, Douglas; Khaper, Neelam

    2017-03-20

    Pulmonary arterial hypertension (PAH) occurs when remodeling of pulmonary vessels leads to increased pulmonary vascular resistance resulting in increased pulmonary arterial pressure. Increased pulmonary arterial pressure results in right ventricle hypertrophy and eventually heart failure. Oxidative stress has been implicated in the pathogenesis of PAH and may play a role in the regulation of cellular signaling involved in cardiac response to pressure overload. Secoisolariciresinol diglucoside (SDG), a component from flaxseed, has been shown to reduce cardiac oxidative stress in various pathophysiological conditions. We investigated the potential protective effects of SDG in a monocrotaline-induced model of PAH. Five- to six-week-old male Wistar rats were given a single intraperitoneal injection of monocrotaline (60 mg/kg) and sacrificed 21 days later where heart, lung, and plasma were collected. SDG (25 mg/kg) was given via gavage as either a 21-day co-treatment or pre-treatment of 14 days before monocrotaline administration and continued for 21 days. Monocrotaline led to right ventricle hypertrophy, increased lipid peroxidation, and elevated plasma levels of alanine transaminase (ALT) and aspartate transaminase (AST). Co-treatment with SDG did not attenuate hypertrophy or ALT and AST levels but decreased reactive oxygen species (ROS) levels and catalase and superoxide dismutase activity compared to the monocrotaline-treated group. Pre-treatment with SDG decreased right ventricle hypertrophy, ROS levels, lipid peroxidation, catalase, superoxide dismutase, and glutathione peroxidase activity and plasma levels of ALT and AST when compared to the monocrotaline group. These findings indicate that pre-treatment with SDG provided better protection than co-treatment in this model of right heart dysfunction, suggesting an important role for SDG in PAH and right ventricular remodeling.

  19. Cardiac Energy Metabolism and Oxidative Stress Biomarkers in Diabetic Rat Treated with Resveratrol

    PubMed Central

    Carolo dos Santos, Klinsmann; Pereira Braga, Camila; Octavio Barbanera, Pedro; Rodrigues Ferreira Seiva, Fábio; Fernandes Junior, Ary; Fernandes, Ana Angélica Henrique

    2014-01-01

    Resveratrol (RSV), polyphenol from grape, was studied to evaluate its effects on calorimetric parameters, energy metabolism, and antioxidants in the myocardium of diabetic rats. The animals were randomly divided into four groups (n = 8): C (control group): normal rats; C-RSV: normal rats receiving RSV; DM: diabetic rats; and DM-RSV: diabetics rats receiving RSV. Type 1 diabetes mellitus was induced with administration of streptozotocin (STZ; 60 mg−1 body weight, single dose, i.p.). After 48 hours of STZ administration, the animals received RSV (1.0 mg/kg/day) for gavage for 30 days. Food, water, and energy intake were higher in the DM group, while administration of RSV caused decreases (p<0.05) in these parameters. The glycemia decreased and higher final body weight increased in DM-RSV when compared with the DM group. The diabetic rats showed higher serum-free fatty acid, which was normalized with RSV. Oxygen consumption (VO2) and carbon dioxide production (VCO2) decreased (p<0.05) in the DM group. This was accompanied by reductions in RQ. The C-RSV group showed higher VO2 and VCO2 values. Pyruvate dehydrogenase activity was lower in the DM group and normalizes with RSV. The DM group exhibited higher myocardial β-hydroxyacyl coenzyme-A dehydrogenase and citrate synthase activity, and RSV decreased the activity of these enzymes. The DM group had higher cardiac lactate dehydrogenase compared to the DM-RSV group. Myocardial protein carbonyl was increased in the DM group. RSV increased reduced glutathione in the cardiac tissue of diabetic animals. The glutathione reductase activity was higher in the DM-RSV group compared to the DM group. In conclusion, diabetes is accompanied by cardiac energy metabolism dysfunction and change in the biomarkers of oxidative stress. The cardioprotective effect may be mediated through RVS's ability to normalize free fatty acid oxidation, enhance utilization glucose, and control the biomarkers' level of oxidative stress under

  20. Non-Invasive Radiofrequency-Induced Targeted Hyperthermia for the Treatment of Hepatocellular Carcinoma

    PubMed Central

    Raoof, Mustafa; Curley, Steven A.

    2011-01-01

    Targeted biological therapies for hepatocellular cancer have shown minimal improvements in median survival. Multiple pathways to oncogenesis leading to rapid development of resistance to such therapies is a concern. Non-invasive radiofrequency field-induced targeted hyperthermia using nanoparticles is a radical departure from conventional modalities. In this paper we underscore the need for innovative strategies for the treatment of hepatocellular cancer, describe the central paradigm of targeted hyperthermia using non-invasive electromagnetic energy, review the process of characterization and modification of nanoparticles for the task, and summarize data from cell-based and animal-based models of hepatocellular cancer treated with non-invasive RF energy. Finally, future strategies and challenges in bringing this modality from bench to clinic are discussed. PMID:21994866

  1. Non-invasive Central and Peripheral Stimulation: New Hope for Essential Tremor?

    PubMed Central

    Chalah, Moussa A.; Lefaucheur, Jean-Pascal; Ayache, Samar S.

    2015-01-01

    Essential tremor (ET) is among the most frequent movement disorders. It usually manifests as a postural and kinematic tremor of the arms, but may also involve the head, voice, lower limbs, and trunk. An oscillatory network has been proposed as a neural correlate of ET, and is mainly composed of the olivocerebellar system, thalamus, and motor cortex. Since pharmacological agents have limited benefits, surgical interventions like deep brain stimulation are the last-line treatment options for the most severe cases. Non-invasive brain stimulation techniques, particularly transcranial magnetic or direct current stimulation, are used to ameliorate ET. Their non-invasiveness, along with their side effects profile, makes them an appealing treatment option. In addition, peripheral stimulation has been applied in the same perspective. Hence, the aim of the present review is to shed light on the emergent use of non-invasive central and peripheral stimulation techniques in this interesting context. PMID:26635516

  2. [Non-invasive mechanical ventilation in the pre- and intraoperative period and difficult airway].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive mechanical ventilation is a method of ventilatory assistance aimed at increasing alveolar ventilation, thus achieving, in selected subjects, the avoidance of endotracheal intubation and invasive mechanical ventilation, with the consequent improvement in survival. There has been a systematic review and study of the technical, clinical experiences, and recommendations concerning the application of non-invasive mechanical ventilation in the pre- and intraoperative period. The use of prophylactic non-invasive mechanical ventilation before surgery that involves significant alterations in the ventilatory function may decrease the incidence of postoperative respiratory complications. Its intraoperative use will mainly depend on the type of surgery, type of anaesthetic technique, and the clinical status of the patient. Its use allows greater anaesthetic depth without deterioration of oxygenation and ventilation of patients.

  3. Non-invasive quantification of hemodynamics in human choriocapillaries

    NASA Astrophysics Data System (ADS)

    Yu, Huidan (Whitney); Chen, Rou; An, Senyou; McDonough, James; Gelfand, Bradley; Yao, Jun

    2016-11-01

    The development of retinal disease is inextricably linked to defects in the choroidal blood supply. However, to date a description of the hemodynamics in the human choroidal circulation is lacking. Through high resolution choroidal vascular network mapped from immunofluorescent labeling and confocal microscopy of human cadaver donor eyes. We noninvasively quantify hemodynamics including velocity, pressure, and wall-shear stress (WSS) in choriocapillaries through mesoscale modeling and GPU-accelerated fast computation. This is the first-ever map of hemodynamic parameters (WSS, pressure, and velocity) in anatomically accurate human choroidal vasculature in health and disease. The pore scale simulation results are used to evaluate porous media models with the same porosity and boundary conditions. School of Medicine, Indiana University.

  4. Usefulness for Predicting Cardiac Events After Orthotopic Liver Transplantation of Myocardial Perfusion Imaging and Dobutamine Stress Echocardiography Preoperatively.

    PubMed

    Snipelisky, David; Ray, Jordan; Vallabhajosyula, Saraschandra; Matcha, Gautam; Squier, Samuel; Lewis, Jacob; Holliday, Rex; Aggarwal, Niti; Askew, J Wells; Shapiro, Brian; Anavekar, Nandan

    2017-04-01

    Patients undergoing orthotopic liver transplantation have high rates of cardiac morbidity and mortality. Although guidelines recommend noninvasive stress testing as part of the preoperative evaluation, little data have evaluated clinical outcomes following orthotopic liver transplantation. A retrospective study at 2 high-volume liver transplantation centers was performed. All patients undergoing noninvasive stress testing (myocardial perfusion imaging [MPI] or dobutamine stress echocardiography [DSE]) over a 5-year period were included. Descriptive analyses, including clinical outcomes and perioperative and postoperative ischemic events, were performed. Comparisons were made between subsets of patients within each stress modality based on abnormal versus normal results. A total of 506 patients were included, of which 343 underwent DSE and 163 MPI. Few patients had abnormal results, with 19 (5.5%) in the DSE group and 13 (8%) in the MPI group. Perioperative and postoperative cardiac complications were low (n = 20, 5.8% and n = 3, 0.9% in DSE group and n = 15, 9.2% and n = 3, 1.8% in MPI group). Comparisons between abnormal versus normal findings showed a trend toward periprocedural cardiac complications in the abnormal DSE group (n = 3, 15.8% vs n = 17, 5.25%; p = 0.09) with no difference in 6-month postprocedural complications (n = 0 vs n = 3, 0.9%; p = 1.0). In the MPI group, a trend toward periprocedural ischemic complications (n = 3, 23.1% vs n = 12, 8%; p = 0.1) was noted with no difference in 6-month postprocedural complications (n = 0 vs n = 3, 2%; p = 1.0). In conclusion, our study found a significantly lower than reported cardiac event rate. In addition, it demonstrated that ischemic cardiac events are uncommon in patients with normal stress testing.

  5. Personalized management of cirrhosis by non-invasive tests of liver fibrosis

    PubMed Central

    Wong, Grace Lai-Hung; Espinosa, Wendell Zaragoza

    2015-01-01

    Owing to the high prevalence of various chronic liver diseases, cirrhosis is one of the leading causes of morbidity and mortality worldwide. In recent years, the development of non-invasive tests of fibrosis allows accurate diagnosis of cirrhosis and reduces the need for liver biopsy. In this review, we discuss the application of these non-invasive tests beyond the diagnosis of cirrhosis. In particular, their role in the selection of patients for hepatocellular carcinoma surveillance and varices screening is highlighted. PMID:26523265

  6. Recent advances in the development of Raman spectroscopy for deep non-invasive medical diagnosis.

    PubMed

    Matousek, Pavel; Stone, Nicholas

    2013-01-01

    Raman spectroscopy has recently undergone major advances in the area of deep non-invasive characterisation of biological tissues. The progress stems from the development of spatially offset Raman spectroscopy (SORS) and renaissance of transmission Raman spectroscopy permitting the assessment of diffusely scattering samples at depths several orders of magnitude deeper than possible with conventional Raman spectroscopy. Examples of emerging applications include non-invasive diagnosis of bone disease, cancer and monitoring of glucose levels. This article reviews this fast moving field focusing on recent developments within the medical area.

  7. [Non-invasive mechanical ventilation in the treatment of acute heart failure].

    PubMed

    Alfonso Megido, Joaquín; González Franco, Alvaro

    2014-03-01

    When acute heart failure progresses and there is acute cardiogenic pulmonary edema, routine therapeutic measures should be accompanied by other measures that help to correct oxygenation of the patient. The final and most drastic step is mechanical ventilation. Non-invasive ventilation has been developed in the last few years as a method that attempts to improve oxygenation without the need for intubation, thus, in theory, reducing morbidity and mortality in these patients. The present article describes the controversies surrounding the results of this technique and discusses its indications. The article also discusses how to start non-invasive ventilation in patients with acute pulmonary edema from a practical point of view.

  8. Maternal high-fat diet impairs cardiac function in offspring of diabetic pregnancy through metabolic stress and mitochondrial dysfunction

    PubMed Central

    Mdaki, Kennedy S.; Larsen, Tricia D.; Wachal, Angela L.; Schimelpfenig, Michelle D.; Weaver, Lucinda J.; Dooyema, Samuel D. R.; Louwagie, Eli J.

    2016-01-01

    Offspring of diabetic pregnancies are at risk of cardiovascular disease at birth and throughout life, purportedly through fuel-mediated influences on the developing heart. Preventative measures focus on glycemic control, but the contribution of additional offenders, including lipids, is not understood. Cellular bioenergetics can be influenced by both diabetes and hyperlipidemia and play a pivotal role in the pathophysiology of adult cardiovascular disease. This study investigated whether a maternal high-fat diet, independently or additively with diabetes, could impair fuel metabolism, mitochondrial function, and cardiac physiology in the developing offspring's heart. Sprague-Dawley rats fed a control or high-fat diet were administered placebo or streptozotocin to induce diabetes during pregnancy and then delivered offspring from four groups: control, diabetes exposed, diet exposed, and combination exposed. Cardiac function, cellular bioenergetics (mitochondrial stress test, glycolytic stress test, and palmitate oxidation assay), lipid peroxidation, mitochondrial histology, and copy number were determined. Diabetes-exposed offspring had impaired glycolytic and respiratory capacity and a reduced proton leak. High-fat diet-exposed offspring had increased mitochondrial copy number, increased lipid peroxidation, and evidence of mitochondrial dysfunction. Combination-exposed pups were most severely affected and demonstrated cardiac lipid droplet accumulation and diastolic/systolic cardiac dysfunction that mimics that of adult diabetic cardiomyopathy. This study is the first to demonstrate that a maternal high-fat diet impairs cardiac function in offspring of diabetic pregnancies through metabolic stress and serves as a critical step in understanding the role of cellular bioenergetics in developmentally programmed cardiac disease. PMID:26801311

  9. Preliminary evidence that exercise dependence is associated with blunted cardiac and cortisol reactions to acute psychological stress.

    PubMed

    Heaney, Jennifer L J; Ginty, Annie T; Carroll, Douglas; Phillips, Anna C

    2011-02-01

    Low or blunted cardiovascular and cortisol reactions to acute psychological stress have been shown to characterise those with a tobacco or alcohol dependency. The present study tested the hypothesis that exercise dependency would be similarly associated with blunted reactivity. Young female exercisers (N=219) were screened by questionnaire for exercise dependence. Ten women with probable exercise dependence and 10 non dependent controls were selected for laboratory stress testing. Cardiovascular activity and salivary cortisol were measured at rest and in response to a 10-min mental arithmetic stress task. The exercise dependent women showed blunted cardiac reactions to the stress task and blunted cortisol at 10, 20, and 30 minute post stress exposure. These effects could not be accounted for in terms of group differences in stress task performance, nor could the cardiac effects be attributed to group differences in cardio-respiratory fitness. It would seem that low stress reactivity is characteristic of a wide range of dependencies, and is not confined to substance dependence. Our results offer further support for the hypothesis that blunted stress reactivity may be a peripheral marker of a central motivational dysregulation.

  10. Oxidative stress and redox signalling in cardiac hypertrophy and heart failure

    PubMed Central

    Seddon, Mike; Looi, Yee H; Shah, Ajay M

    2007-01-01

    Substantial evidence suggests the involvement of oxidative stress in the pathophysiology of congestive heart failure and its antecedent conditions such as cardiac hypertrophy and adverse remodelling after MI. Oxidative stress describes an imbalance between antioxidant defences and the production of reactive oxygen species (ROS), which at high levels cause cell damage but at lower levels induce subtle changes in intracellular signalling pathways (termed redox signalling). ROS are derived from many sources including mitochondria, xanthine oxidase, uncoupled nitric oxide synthases and NADPH oxidases. The latter enzymes are especially important in redox signalling, being implicated in the pathophysiology of hypertension and atherosclerosis, and activated by diverse pathologically relevant stimuli. We review the contribution of ROS to heart failure pathophysiology and discuss potential therapies that may specifically target detrimental redox signalling. Indeed, drugs such as ACE inhibitors and statins may act in part through such mechanisms. A better understanding of redox signalling mechanisms may enable the development of new targeted therapeutic strategies rather than the non‐specific antioxidant approaches that have to date been disappointing in clinical trials. PMID:16670100

  11. Deficiency of methionine sulfoxide reductase A causes cellular dysfunction and mitochondrial damage in cardiac myocytes under physical and oxidative stresses

    SciTech Connect

    Nan, Changlong; Li, Yuejin; Jean-Charles, Pierre-Yves; Chen, Guozhen; Kreymerman, Alexander; Prentice, Howard; Weissbach, Herbert; Huang, Xupei

    2010-11-26

    Research highlights: {yields} Deficiency of MsrA in the heart renders myocardial cells more sensitive to oxidative stress. {yields} Mitochondrial damage happens in the heart lacking MsrA. {yields} More protein oxidation in myocardial cells lacking MsrA. {yields} MsrA protects the heart against oxidative stress. -- Abstract: Methionine sulfoxide reductase A (MsrA) is an enzyme that reverses oxidation of methionine in proteins. Using a MsrA gene knockout (MsrA{sup -/-}) mouse model, we have investigated the role of MsrA in the heart. Our data indicate that cellular contractility and cardiac function are not significantly changed in MsrA{sup -/-} mice if the hearts are not stressed. However, the cellular contractility, when stressed using a higher stimulation frequency (2 Hz), is significantly reduced in MsrA{sup -/-} cardiac myocytes. MsrA{sup -/-} cardiac myocytes also show a significant decrease in contractility after oxidative stress using H{sub 2}O{sub 2}. Corresponding changes in Ca{sup 2+} transients are observed in MsrA{sup -/-} cardiomyocytes treated with 2 Hz stimulation or with H{sub 2}O{sub 2}. Electron microscope analyses reveal a dramatic morphological change of mitochondria in MsrA{sup -/-} mouse hearts. Further biochemical measurements indicate that protein oxidation levels in MsrA{sup -/-} mouse hearts are significantly higher than those in wild type controls. Our study demonstrates that the lack of MsrA in cardiac myocytes reduces myocardial cell's capability against stress stimulations resulting in a cellular dysfunction in the heart.

  12. Cardiac and pulmonary oxidative stress in rats exposed to realistic emissions of source aerosols

    PubMed Central

    Lemos, Miriam; Diaz, Edgar A.; Gupta, Tarun; Kang, Choong-Min; Ruiz, Pablo; Coull, Brent A.; Godleski, John J.; Gonzalez-Flecha, Beatriz

    2013-01-01

    In vivo chemiluminescence (CL) is a measure of reactive oxygen species in tissues. CL was used to assess pulmonary and cardiac responses to inhaled aerosols derived from aged emissions of three coal-fired power plants in the USA. Sprague–Dawley rats were exposed to either filtered air or: (1) primary emissions (P); (2) ozone oxidized emissions (PO); (3) oxidized emissions + secondary organic aerosol (SOA) (POS); (4) neutralized oxidized emissions + SOA (PONS); and (5) control scenarios: oxidized emissions + SOA in the absence of primary particles (OS), oxidized emissions alone (O), and SOA alone (S). Immediately after 6 hours of exposure, CL in the lung and heart was measured. Tissues were also assayed for thiobarbituric acid reactive substances (TBARS). Exposure to P or PO aerosols led to no changes compared to filtered air in lung or heart CL at any individual plant or when all data were combined. POS caused significant increases in lung CL and TBARS at only one plant, and not in combined data from all plants; PONS resulted in increased lung CL only when data from all plants were combined. Heart CL was also significantly increased with exposure to POS only when data from all plants were combined. PONS increased heart CL significantly in one plant with TBARS accumulation, but not in combined data. Exposure to O, OS, and S had no CL effects. Univariate analyses of individual measured components of the exposure atmospheres did not identify any component associated with increased CL. These data suggest that coal-fired power plant emissions combined with other atmospheric constituents produce limited pulmonary and cardiac oxidative stress. PMID:21913821

  13. Non-Invasive Management of Madura Foot with Oral Posaconazole and Ciprofloxacin

    PubMed Central

    Sharma, Amit M.; Sharma, Namita; Nat, Amritpal; Rane, Meghan; Endy, Timothy P.

    2014-01-01

    Madura foot is a chronic infection caused by fungus and/or bacteria. Traditionally, treatment has been surgical debridement or amputation. Non-invasive management with long-term antimicrobials alone has been reported as successful. We report a case of Madura foot in a Somali refugee successfully managed with oral posaconazole and ciprofloxacin. PMID:25349373

  14. Hypercapnic encephalopathy syndrome: a new frontier for non-invasive ventilation?

    PubMed

    Scala, Raffaele

    2011-08-01

    According to the classical international guidelines, non-invasive ventilation is contraindicated in hypercapnic encephalopathy syndrome (HES) due to the poor compliance to ventilatory treatment of confused/agitated patients and the risk of aspirative pneumonia related to lack of airways protection. As a matter of fact, conventional mechanical ventilation has been recommended as "golden standard" in these patients. However, up to now there are not controlled data that have demonstrated in HES the advantage of conventional mechanical ventilation vs non-invasive ventilation. In fact, patients with altered mental status have been systematically excluded from the randomised and controlled trials performed with non-invasive ventilation in hypercapnic acute respiratory failure. Recent studies have clearly demonstrated that an initial cautious NPPV trial in selected HES patients may be attempt as long as there are no other contraindications and the technique is provided by experienced caregivers in a closely monitored setting where ETI is always readily available. The purpose of this review is to report the physiologic rationale, the clinical feasibility and the still open questions about the careful use of non-invasive ventilation in HES as first-line ventilatory strategy in place of conventional mechanical ventilation via endotracheal intubation.

  15. A meta-analysis of trait differences between invasive and non-invasive plant species.

    PubMed

    van Kleunen, Mark; Weber, Ewald; Fischer, Markus

    2010-02-01

    A major aim in ecology is identifying determinants of invasiveness. We performed a meta-analysis of 117 field or experimental-garden studies that measured pair-wise trait differences of a total of 125 invasive and 196 non-invasive plant species in the invasive range of the invasive species. We tested whether invasiveness is associated with performance-related traits (physiology, leaf-area allocation, shoot allocation, growth rate, size and fitness), and whether such associations depend on type of study and on biogeographical or biological factors. Overall, invasive species had significantly higher values than non-invasive species for all six trait categories. More trait differences were significant for invasive vs. native comparisons than for invasive vs. non-invasive alien comparisons. Moreover, for comparisons between invasive species and native species that themselves are invasive elsewhere, no trait differences were significant. Differences in physiology and growth rate were larger in tropical regions than in temperate regions. Trait differences did not depend on whether the invasive alien species originates from Europe, nor did they depend on the test environment. We conclude that invasive alien species had higher values for those traits related to performance than non-invasive species. This suggests that it might become possible to predict future plant invasions from species traits.

  16. Smartphone spectrometer for non-invasive diffuse reflectance spectroscopy based hemoglobin sensing (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Edwards, Perry S.

    2016-10-01

    Fiber-optic based diffuse reflectance spectroscopy (DRS) is shown to be a highly specific and highly sensitive method for non-invasive detection of various cancers (e.g. cervical and oral) as well as many other diseases. Fiber-optic DRS diagnosis relies on non-invasive biomarker detection (e.g. oxy- and deoxy-hemoglobin) and can be done without the need for sophisticated laboratory analysis of samples. Thus, it is highly amenable for clinical adoption especially in resource scarce regions that have limited access to such developed laboratory infrastructure. Despite the demonstrated effectiveness of fiber-optic DRS, such systems remain cost prohibitive in many of these regions, mainly due to the use of bulky and expensive spectrometers. Here, a fiber-optic DRS system is coupled to a smartphone spectrometer and is proposed as a low-cost solution for non-invasive tissue hemoglobin sensing. The performance of the system is assessed by measuring tissue phantoms with varying hemoglobin concentrations. A DRS retrieval algorithm is used to extract hemoglobin parameters from the measurements and determine the accuracy of the system. The results are then compared with those of a previously reported fiber-optic DRS system which is based on a larger more expensive spectrometer system. The preliminary results are encouraging and indicate the potential of the smartphone spectrometer as a viable low-cost option for non-invasive tissue hemoglobin sensing.

  17. Non Invasive Biomedical Analysis - Breath Networking Session at PittCon 2011, Atlanta, Georgia

    EPA Science Inventory

    This was the second year that our breath colleagues organized a networking session at the Pittsburgh Conference and Exposition or ''PittCon'' (http://www.pincon.org/).This time it was called "Non-invasive Biomedical Analysis" to broaden the scope a bit, but the primary focus rema...

  18. Invasive versus Non Invasive Methods Applied to Mummy Research: Will This Controversy Ever Be Solved?

    PubMed

    Moissidou, Despina; Day, Jasmine; Shin, Dong Hoon; Bianucci, Raffaella

    2015-01-01

    Advances in the application of non invasive techniques to mummified remains have shed new light on past diseases. The virtual inspection of a corpse, which has almost completely replaced classical autopsy, has proven to be important especially when dealing with valuable museum specimens. In spite of some very rewarding results, there are still many open questions. Non invasive techniques provide information on hard and soft tissue pathologies and allow information to be gleaned concerning mummification practices (e.g., ancient Egyptian artificial mummification). Nevertheless, there are other fields of mummy studies in which the results provided by non invasive techniques are not always self-explanatory. Reliance exclusively upon virtual diagnoses can sometimes lead to inconclusive and misleading interpretations. On the other hand, several types of investigation (e.g., histology, paleomicrobiology, and biochemistry), although minimally invasive, require direct contact with the bodies and, for this reason, are often avoided, particularly by museum curators. Here we present an overview of the non invasive and invasive techniques currently used in mummy studies and propose an approach that might solve these conflicts.

  19. Updates on the use of non-invasive brain stimulation in physical and rehabilitation medicine.

    PubMed

    Williams, Julie A; Imamura, Marta; Fregni, Felipe

    2009-04-01

    Brain stimulation for the treatment of neuropsychiatric diseases has been used for more than 50 years. Although its development has been slow, current advances in the techniques of brain stimulation have improved its clinical efficacy. The use of non-invasive brain stimulation has significant advantages, such as not involving surgical procedures and having relatively mild adverse effects. In this paper we briefly review the use of 2 non-invasive brain stimulation techniques, repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), as therapeutic approaches in physical and rehabilitation medicine. We also compare the effects of non-invasive central nervous system stimulation with techniques of non-invasive peripheral electrical stimulation, in order to provide new insights for future developments. Although the outcomes of these initial trials include some conflicting results, the evidence supports that rTMS and tDCS might have a therapeutic value in different neurological conditions. Studies published within the last year have examined new approaches of stimulation, such as longer intensities of stimulation, new electrode sizes for tDCS, novel coils for stimulation of deeper areas, and new frequencies of stimulation for rTMS. These new approaches need to be tested in larger clinical trials in order to determine whether they offer significant clinical effects.

  20. Application of quantum dot nanoparticles for potential non-invasive bio-imaging of mammalian spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various obstacles are encountered by mammalian spermatozoa during their journey through the female genital tract, and only few or none will reach the site of fertilization. Currently, there are limited technical approaches for non-invasive investigation of spermatozoa migration after insemination. A...

  1. Differential radioactivity monitor for non-invasive detection of ocular melanoma

    DOEpatents

    Lambrecht, R.M.; Packer, S.

    1982-09-23

    There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

  2. Invasive versus Non Invasive Methods Applied to Mummy Research: Will This Controversy Ever Be Solved?

    PubMed Central

    Moissidou, Despina; Day, Jasmine; Shin, Dong Hoon; Bianucci, Raffaella

    2015-01-01

    Advances in the application of non invasive techniques to mummified remains have shed new light on past diseases. The virtual inspection of a corpse, which has almost completely replaced classical autopsy, has proven to be important especially when dealing with valuable museum specimens. In spite of some very rewarding results, there are still many open questions. Non invasive techniques provide information on hard and soft tissue pathologies and allow information to be gleaned concerning mummification practices (e.g., ancient Egyptian artificial mummification). Nevertheless, there are other fields of mummy studies in which the results provided by non invasive techniques are not always self-explanatory. Reliance exclusively upon virtual diagnoses can sometimes lead to inconclusive and misleading interpretations. On the other hand, several types of investigation (e.g., histology, paleomicrobiology, and biochemistry), although minimally invasive, require direct contact with the bodies and, for this reason, are often avoided, particularly by museum curators. Here we present an overview of the non invasive and invasive techniques currently used in mummy studies and propose an approach that might solve these conflicts. PMID:26345295

  3. Non-Invasive NIR Sensor for Quantification of Deep Tissue Oxygenation. Phase 1.

    DTIC Science & Technology

    1995-10-01

    be determined by differential absorption spectroscopy using two wavelengths, 0/oSat- ga(, l)/p[a(X2)I [ Hielscher , et al., 1993; Haida and Chance...Biol 345:829-35, 1994. Hielscher AH, Tittel FK, and Jacques SL: Non-invasive monitoring of blood oxygenation by phase resolved transmission spectroscopy

  4. Quantitative molecular sensing in biological tissues: an approach to non-invasive optical characterization

    NASA Astrophysics Data System (ADS)

    Chandra, Malavika; Vishwanath, Karthik; Fichter, Greg D.; Liao, Elly; Hollister, Scott J.; Mycek, Mary-Ann

    2006-06-01

    A method to non-invasively and quantitatively characterize thick biological tissues by combining both experimental and computational approaches in tissue optical spectroscopy was developed and validated on fifteen porcine articular cartilage (AC) tissue samples. To the best of our knowledge, this study is the first to couple non-invasive reflectance and fluorescence spectroscopic measurements on freshly harvested tissues with Monte Carlo computational modeling of time-resolved propagation of both excitation light and multi-fluorophore emission. For reflectance, quantitative agreement between simulation and experiment was achieved to better than 11%. Fluorescence data and simulations were used to extract the ratio of the absorption coefficients of constituent fluorophores for each measured AC tissue sample. This ratio could be used to monitor relative changes in concentration of the constituent fluorophores over time. The samples studied possessed the complexity and variability not found in artificial tissue-simulating phantoms and serve as a model for future optical molecular sensing studies on tissue engineered constructs intended for use in human therapeutics. An optical technique that could non-invasively and quantitatively assess soft tissue composition or physiologic status would represent a significant advance in tissue engineering. Moreover, the general approach described here for optical characterization should be broadly applicable to quantitative, non-invasive molecular sensing applications in complex, three-dimensional biological tissues.

  5. Combined heart rate variability and dynamic measures for quantitatively characterizing the cardiac stress status during cycling exercise.

    PubMed

    Chen, Szi-Wen; Liaw, Jiunn-Woei; Chang, Ya-Ju; Chuang, Li-Ling; Chien, Chun-Tse

    2015-08-01

    In this study, we aimed to seek for different ways of measuring cardiac stress in terms of heart rate variability (HRV) and heart rate (HR) dynamics, and to develop a novel index that can effectively summarize the information reflected by these measures to continuously and quantitatively characterize the cardiac stress status during physical exercise. Standard deviation, spectral measure of HRV as well as a nonlinear detrended fluctuation analysis (DFA) based fractal-like behavior measure of HR dynamics were all evaluated on the RR time series derived from windowed electrocardiogram (ECG) data for the subjects undergoing cycling exercise. We recruited eleven young healthy subjects in our tests. Each subject was asked to maintain a fixed speed under a constant load during the pedaling test. We obtained the running estimates of the standard deviation of the normal-to-normal interval (SDNN), the high-fidelity power spectral density (PSD) of HRV, and the DFA scaling exponent α, respectively. A trend analysis and a multivariate linear regression analysis of these measures were then performed. Numerical experimental results produced by our analyses showed that a decrease in both SDNN and α was seen during the cycling exercise, while there was no significant correlation between the standard lower frequency to higher frequency (LF-to-HF) spectral power ratio of HRV and the exercise intensity. In addition, while the SDNN and α were both negatively correlated with the Borg rating of perceived exertion (RPE) scale value, it seemed that the LF-to-HF power ratio might not have substantial impact on the Borg value, suggesting that the SDNN and α may be further used as features to detect the cardiac stress status during the physical exercise. We further approached this detection problem by applying a linear discriminant analysis (LDA) to both feature candidates for the task of cardiac stress stratification. As a result, a time-varying parameter, referred to as the cardiac

  6. Tissue Doppler characterization of cardiac phenotype in mouse.

    PubMed

    Fayssoil, Abdallah

    2009-10-01

    Mice allow biologists to study various genes playing a role in cardiac function and pathophysiological situations. Echocardiography is a non-invasive tool for assessing cardiac phenotype. Because of load dependence of conventional parameters (left ventricular shortening fraction, left ventricular ejection fraction and mitral pulsed Doppler), we have to perform Doppler tissular velocity imaging and strain imaging for the characterization of cardiomyopathies mice models.

  7. Enhanced open-loop but not closed-loop cardiac baroreflex sensitivity during orthostatic stress in humans.

    PubMed

    Akimoto, Toshinari; Sugawara, Jun; Ichikawa, Daisuke; Terada, Nobuyuki; Fadel, Paul J; Ogoh, Shigehiko

    2011-11-01

    The neural interaction between the cardiopulmonary and arterial baroreflex may be critical for the regulation of blood pressure during orthostatic stress. However, studies have reported conflicting results: some indicate increases and others decreases in cardiac baroreflex sensitivity (i.e., gain) with cardiopulmonary unloading. Thus the effect of orthostatic stress-induced central hypovolemia on regulation of heart rate via the arterial baroreflex remains unclear. We sought to comprehensively assess baroreflex function during orthostatic stress by identifying and comparing open- and closed-loop dynamic cardiac baroreflex gains at supine rest and during 60° head-up tilt (HUT) in 10 healthy men. Closed-loop dynamic "spontaneous" cardiac baroreflex sensitivities were calculated by the sequence technique and transfer function and compared with two open-loop carotid-cardiac baroreflex measures using the neck chamber system: 1) a binary white-noise method and 2) a rapid-pulse neck pressure-neck suction technique. The gain from the sequence technique was decreased from -1.19 ± 0.14 beats·min(-1)·mmHg(-1) at rest to -0.78 ± 0.10 beats·min(-1)·mmHg(-1) during HUT (P = 0.005). Similarly, closed-loop low-frequency baroreflex transfer function gain was reduced during HUT (P = 0.033). In contrast, open-loop low-frequency transfer function gain between estimated carotid sinus pressure and heart rate during white-noise stimulation was augmented during HUT (P = 0.01). This result was consistent with the maximal gain of the carotid-cardiac baroreflex stimulus-response curve (from 0.47 ± 0.15 beats·min(-1)·mmHg(-1) at rest to 0.60 ± 0.20 beats·min(-1)·mmHg(-1) at HUT, P = 0.037). These findings suggest that open-loop cardiac baroreflex gain was enhanced during HUT. Moreover, under closed-loop conditions, spontaneous baroreflex analyses without external stimulation may not represent open-loop cardiac baroreflex characteristics during orthostatic stress.

  8. Non-Invasive Measurements of Carboxyhemoglobin and Methemoglobin in Children with Sickle Cell Disease

    PubMed Central

    Caboot, Jason B.; Jawad, Abbas F.; McDonough, Joseph M.; Bowdre, Cheryl Y.; Arens, Raanan; Marcus, Carole L.; Mason, Thornton B.A.; Smith-Whitley, Kim; Ohene-Frempong, Kwaku; Allen, Julian L.

    2012-01-01

    SUMMARY Assessment of oxyhemoglobin saturation in patients with sickle cell disease (SCD) is vital for prompt recognition of hypoxemia. The accuracy of pulse oximeter measurements of blood oxygenation in SCD patients is variable, partially due to carboxyhemoglobin (COHb) and methemoglobin (MetHb), which decrease the oxygen content of blood. This study evaluated the accuracy and reliability of a non-invasive pulse co-oximeter in measuring COHb and MetHb percentages (SpCO and SpMet) in children with SCD. We hypothesized that measurements of COHb and MetHb by non-invasive pulse co-oximetry agree within acceptable clinical accuracy with those made by invasive whole blood co-oximetry. Fifty children with SCD-SS underwent pulse co-oximetry and blood co-oximetry while breathing room air. Non-invasive COHb and MetHb readings were compared to the corresponding blood measurements. The pulse co-oximeter bias was 0.1% for COHb and −0.22% for MetHb. The precision of the measured SpCO was ±2.1% within a COHb range of 0.4–6.1%, and the precision of the measured SpMet was ±0.33% within a MetHb range of 0.1–1.1%. Non-invasive pulse co-oximetry was useful in measuring COHb and MetHb levels in children with SCD. Although the non-invasive technique slightly overestimated the invasive COHb measurements and slightly underestimated the invasive MetHb measurements, there was close agreement between the two methods. PMID:22328189

  9. Low-cost and disposable pressure sensor mat for non-invasive sleep and movement monitoring applications.

    PubMed

    Abraham, Jose K; Sullivan, Shawn; Ranganathan, Sridhar

    2011-01-01

    Sleep has profound effects on the physical and mental well-being of an individual. The National Institutes of Health (NIH) Sleep Disorder Research Plan gives particular emphasis to non-invasive sleep monitoring methods. Older adults experience sleep fragmentation due to sleep disorders. Unobtrusive non-contact monitoring can be the only realistic solution for long term home-based sleep monitoring. The demand for a low-cost and non-invasive sleep monitoring system for in-home use is more than before due to an increasingly stressful life style. Cost and complexity of current sensor elements hinder the development of low-cost sleep monitoring devices for in-home use. This paper presents the design, development and implementation of a low-cost and disposable pressure sensor mat that could be useful for in-home sleep and movement monitoring applications. The sensor mat design is based on a compressible foam sandwiched between two orthogonal arrays of cPaper capacitance sensors. A low-cost conducting paper has been developed for use as the capacitance sensor electrode. Typical mat design uses a 3 mm thick foam with 5 mm row/column grid array shows that it has a measurement resolution of 0.1 PSI pressure. The resolution can be controlled by both modifying properties of the conducting paper and the foam. Since this pressure mat design is based on low-cost paper, the sensor electrodes are disposable or semi-durable and hence it is ideal for the use in point-of-care physiological monitoring, pervasive healthcare and consumer electronic devices.

  10. Daily sesame oil supplementation attenuates local renin-angiotensin system via inhibiting MAPK activation and oxidative stress in cardiac hypertrophy.

    PubMed

    Liu, Chuan-Teng; Liu, Ming-Yie

    2017-04-01

    The renin-angiotensin system (RAS) is involved in the development of left ventricular hypertrophy (LVH) by which increases cardiac morbidity and mortality. Activation of mitogen-activated protein kinases (MAPKs) and oxidative stress are important in RAS-mediated cardiac hypertrophy. Sesame oil, a potent antioxidant, attenuates hypertension-dependent LVH. We examined the protective role of sesame oil on RAS-mediated MAPK activation and oxidative stress in rats. We induced LVH using a hypertensive model by subcutaneously injecting deoxycorticosterone acetate (DOCA; 15 mg/ml/kg in mineral oil; twice weekly for 5 weeks) and supplementing with 1% sodium chloride drinking water (DOCA/salt) to uninephrectomized rats. Sesame oil was gavaged (0.5 or 1 ml/kg/day for 7 days) after 4 weeks of DOCA/salt treatment. Cardiac histopathology, RAS parameters, expression of MAPKs, reactive oxygen species and lipid peroxidation were assessed 24 h after the last dose of sesame oil. Sesame oil significantly decreased the size of cardiomyocytes and the levels of cardiac renin, angiotensin-converting enzyme and angiotensin II. In addition, sesame oil down-regulated the expression of angiotensin type 1 receptor, JNK and p38 MAPK and apoptosis signal regulating kinase 1, c-Fos and c-Jun in rats receiving DOCA/salt. Furthermore, the induction of nicotinamide adenine dinucleotide phosphate oxidase, superoxide anion and hydroxyl radical and lipid peroxidation by DOCA/salt were inhibited by sesame oil. Sesame oil modulates cardiac RAS to ameliorate LVH by inhibiting MAPK activation and lowering oxidative stress.

  11. EGFR-TKI, erlotinib, causes hypomagnesemia, oxidative stress, and cardiac dysfunction: attenuation by NK-1 receptor blockade.

    PubMed

    Mak, I Tong; Kramer, Jay H; Chmielinska, Joanna J; Spurney, Christopher F; Weglicki, William B

    2015-01-01

    To determine whether the epidermal growth factor receptor tyrosine kinase inhibitor, erlotinib may cause hypomagnesemia, inflammation, and cardiac stress, erlotinib was administered to rats (10 mg · kg(-1)· d(-1)) for 9 weeks. Plasma magnesium decreased progressively between 3 and 9 weeks (-9% to -26%). Modest increases in plasma substance P (SP) occurred at 3 (27%) and 9 (25%) weeks. Neutrophil superoxide-generating activity increased 3-fold, and plasma 8-isoprostane rose 210%, along with noticeable appearance of cardiac perivascular nitrotyrosine. The neurokinin-1 (NK-1) receptor antagonist, aprepitant (2 mg · kg(-1) · d(-1)), attenuated erlotinib-induced hypomagnesemia up to 42%, reduced circulating SP, suppressed neutrophil superoxide activity and 8-isoprostane elevations; cardiac nitrotyrosine was diminished. Echocardiography revealed mild to moderately decreased left ventricular ejection fraction (-11%) and % fractional shortening (-17%) by 7 weeks of erlotinib treatment and significant reduction (-17.5%) in mitral valve E/A ratio at week 9 indicative of systolic and early diastolic dysfunction. Mild thinning of the left ventricular posterior wall suggested early dilated cardiomyopathy. Aprepitant completely prevented the erlotinib-induced systolic and diastolic dysfunction and partially attenuated the anatomical changes. Thus, chronic erlotinib treatment does induce moderate hypomagnesemia, triggering SP-mediated oxidative/inflammation stress and mild-to-moderate cardiac dysfunction, which can largely be corrected by the administration of the SP receptor blocker.

  12. Acute-phase proteins, oxidative stress biomarkers, proinflammatory cytokines, and cardiac troponin in Arabian mares affected with pyometra.

    PubMed

    El-Bahr, S M; El-Deeb, W M

    2016-09-01

    New biomarkers are essential for diagnosis of pyometra in mares. In this context, 12 subfertile Arabian mares suffered from pyometra were admitted to the Veterinary Teaching Hospital. The basis for diagnosis of pyometra was positive findings of clinical examination and rectal palpation. Blood samples were collected from diseased animals and from five Arabian healthy mares, which were considered as control group. Acute-phase proteins (APP), oxidative stress biomarkers, proinflammatory cytokines, and cardiac troponin I were estimated in the harvested sera of both groups. Clinical examination revealed purulent yellowish fluid discharged from vagina of affected animals and rectal palpation of the reproductive tract revealed uterine distention. The biochemical analysis of the serum revealed significant increase in cardiac troponin I, creatin kinase, alkaline phosphatase, malondialdehyde, tumor necrosis factor α, interleukins 6, prostaglandin F2α, haptoglobin, and serum amyloid A and significant decrease in reduced glutathione, superoxide dismutase (SOD), total antioxidant capacity, and nitric oxide (NO) of mares affected with pyometra compare to control. Cardiac troponin I was positively correlated with aspartate aminotransferase, creatin kinase, malondialdehyde, alkaline phosphatase, tumor necrosis factor α, interleukins 6, prostaglandin F2α, haptoglobin and serum amyloid A and negatively correlated with glutathione, superoxide dismutase, total antioxidant capacity and nitric oxide in serum of mares affected with pyometra. Moreover, there was high positive correlation between proinflammatory cytokines and APP in serum of mares affected with pyometra. The present study suggests cardiac troponin I together with APP, proinflammatory cytokines, and oxidative stress parameters as biomarkers for pyometra in Arabian mares.

  13. Diastolic function in healthy humans: non-invasive assessment and the impact of acute and chronic exercise.

    PubMed

    George, Keith P; Naylor, Louise H; Whyte, Greg P; Shave, Rob E; Oxborough, David; Green, Daniel J

    2010-01-01

    Left ventricular (LV) diastolic function is important because the enhanced systolic function that underpins high levels of cardio-respiratory fitness has to be matched by changes in LV filling, and LV diastolic dysfunction plays a key early role in the development and progression of a myriad of cardiovascular diseases. This review serves to detail knowledge in relation to: (1) the definition of diastole and the mechanical processes that occur during the diastolic period, (2) the quantitative assessment of diastolic function, predominantly focusing on non-invasive echocardiographic imaging modes such as tissue Doppler imaging and deformation analysis, (3) the impact of acute aerobic exercise on diastolic function, from the augmentation of function necessary to meet the demand for an increased cardiac output at exercise onset, to current concerns related to the impact of prolonged or ultra-endurance activity on diastolic function during recovery, (4) the adaptation in diastolic function observed with chronic aerobic exercise training in athletes and sedentary individuals who undergo training programmes, and (5) directions for future research.

  14. Low Intensity Physical Exercise Attenuates Cardiac Remodeling and Myocardial Oxidative Stress and Dysfunction in Diabetic Rats

    PubMed Central

    Gimenes, C.; Gimenes, R.; Rosa, C. M.; Xavier, N. P.; Campos, D. H. S.; Fernandes, A. A. H.; Cezar, M. D. M.; Guirado, G. N.; Cicogna, A. C.; Takamoto, A. H. R.; Okoshi, M. P.; Okoshi, K.

    2015-01-01

    We evaluated the effects of a low intensity aerobic exercise protocol on cardiac remodeling and myocardial function in diabetic rats. Wistar rats were assigned into four groups: sedentary control (C-Sed), exercised control (C-Ex), sedentary diabetes (DM-Sed), and exercised diabetes (DM-Ex). Diabetes was induced by intraperitoneal injection of streptozotocin. Rats exercised for 9 weeks in treadmill at 11 m/min, 18 min/day. Myocardial function was evaluated in left ventricular (LV) papillary muscles and oxidative stress in LV tissue. Statistical analysis was given by ANOVA or Kruskal-Wallis. Echocardiogram showed diabetic groups with higher LV diastolic diameter-to-body weight ratio and lower posterior wall shortening velocity than controls. Left atrium diameter was lower in DM-Ex than DM-Sed (C-Sed: 5.73 ± 0.49; C-Ex: 5.67 ± 0.53; DM-Sed: 6.41 ± 0.54; DM-Ex: 5.81 ± 0.50 mm; P < 0.05 DM-Sed vs C-Sed and DM-Ex). Papillary muscle function was depressed in DM-Sed compared to C-Sed. Exercise attenuated this change in DM-Ex. Lipid hydroperoxide concentration was higher in DM-Sed than C-Sed and DM-Ex. Catalase and superoxide dismutase activities were lower in diabetics than controls and higher in DM-Ex than DM-Sed. Glutathione peroxidase activity was lower in DM-Sed than C-Sed and DM-Ex. Conclusion. Low intensity exercise attenuates left atrium dilation and myocardial oxidative stress and dysfunction in type 1 diabetic rats. PMID:26509175

  15. Stress response and cardiac activity of term and preterm calves in the perinatal period.

    PubMed

    Nagel, Christina; Aurich, Jörg; Trenk, Lisa; Ille, Natascha; Drillich, Marc; Pohl, Werner; Aurich, Christine

    2016-10-01

    This study tested the hypothesis of gestational age affecting fetal cardiac activity and the stress response at birth. Heart rate (HR), heart rate variability variables, SD of the beat-to-beat interval and root mean square of successive beat-to-beat differences, and postnatal salivary cortisol concentration were studied in calves born at term (Term, n = 7, gestation length 286.3 ± 2.1 days) or after induction of parturition (Preterm, n = 7, gestation length 279.6 ± 0.2 days). Observation periods covered the last month of gestation (phase A), the last hours before birth including the first stage of labor (phase B), and the neonatal period (phase C). Fetal HR decreased in phase A (P < 0.001) and did not differ between groups. During phase B, HR increased (P < 0.05) and was higher in Preterm than in Term calves in phases B (P < 0.05) and C (P < 0.01). In Term calves, heart rate variability increased from Day 6 until birth (P < 0.05). At birth, SD of the beat-to-beat interval was higher in Term than in Preterm calves (P < 0.01). On Day 1 after birth (phase C), HR accelerations were more frequent in Term than Preterm calves (P < 0.01), whereas decelerations were more frequent in Preterm calves (P < 0.05). Cortisol concentration increased postnatally (P < 0.001) and was correlated with gestation length (r ≥ 0.68, P < 0.01). Because of a certain degree of immaturity, the ability to cope with the stress of birth may be impaired in calves born 1 week before term.

  16. Effects of anisosmotic stress on cardiac muscle cell length, diameter, area, and sarcomere length

    NASA Technical Reports Server (NTRS)

    Tanaka, R.; Barnes, M. A.; Cooper, G. 4th; Zile, M. R.

    1996-01-01

    The purpose of this study was to examine the effects of anisosmotic stress on adult mammalian cardiac muscle cell (cardiocyte) size. Cardiocyte size and sarcomere length were measured in cardiocytes isolated from 10 normal rats and 10 normal cats. Superfusate osmolarity was decreased from 300 +/- 6 to 130 +/- 5 mosM and increased to 630 +/- 8 mosM. Cardiocyte size and sarcomere length increased progressively when osmolarity was decreased, and there were no significant differences between cat and rat cardiocytes with respect to percent change in cardiocyte area or diameter; however, there were significant differences in cardiocyte length (2.8 +/- 0.3% in cat vs. 6.1 +/- 0.3% in rat, P < 0.05) and sarcomere length (3.3 +/- 0.3% in cat vs. 6.1 +/- 0.3% in rat, P < 0.05). To determine whether these species-dependent differences in length were related to diastolic interaction of the contractile elements or differences in relative passive stiffness, cardiocytes were subjected to the osmolarity gradient 1) during treatment with 7 mM 2,3-butanedione monoxime (BDM), which inhibits cross-bridge interaction, or 2) after pretreatment with 1 mM ethylene glycol-bis(beta-aminoethyl ether)-N, N,N',N'-tetraacetic acid (EGTA), a bivalent Ca2+ chelator. Treatment with EGTA or BDM abolished the differences between cat and rat cardiocytes. Species-dependent differences therefore appeared to be related to the degree of diastolic cross-bridge association and not differences in relative passive stiffness. In conclusion, the osmolarity vs. cell size relation is useful in assessing the cardiocyte response to anisosmotic stress and may in future studies be useful in assessing changes in relative passive cardiocyte stiffness produced by pathological processes.

  17. Free-Breathing Cardiac MR Stress Perfusion with Real-Time Slice Tracking

    PubMed Central

    Basha, Tamer A.; Roujol, Sébastien; Kissinger, Kraig V.; Goddu, Beth; Berg, Sophie; Manning, Warren J.; Nezafat, Reza

    2013-01-01

    Purpose To develop a free-breathing cardiac MR perfusion sequence with slice tracking for use after physical exercise. Methods We propose to use a leading navigator, placed immediately before each 2D slice acquisition, for tracking the respiratory motion and updating the slice location in real-time. The proposed sequence was used to acquire CMR perfusion datasets in 12 healthy adult subjects and 8 patients. Images were compared with the conventional perfusion (i.e. without slice tracking) results from the same subjects. The location and geometry of the myocardium were quantitatively analyzed, and the perfusion signal curves were calculated from both sequences to show the efficacy of the proposed sequence. Results The proposed sequence was significantly better compared to the conventional perfusion sequence in terms of qualitative image scores. Changes in the myocardial location and geometry decreased by ~50% in the slice tracking sequence. Furthermore, the proposed sequence had signal curves that are smoother and less noisy. Conclusion The proposed sequence significantly reduces the effect of the respiratory motion on the image acquisition in both rest and stress perfusion scans. PMID:24123153

  18. Cadmium induced cardiac oxidative stress in rats and its attenuation by GSP through the activation of Nrf2 signaling pathway.

    PubMed

    Nazimabashir; Manoharan, Vaihundam; Miltonprabu, Selvaraj

    2015-12-05

    Cadmium (Cd) is one of the toxic heavy metals in the environment, which induces oxidative stress, dyslipidemia and membrane disturbances in heart. The present study was designed to evaluate the role of grape seed proanthocyanidins (GSP) against Cd induced oxidative stress mediated cardio-toxicity in rats. In this study, male Wistar rats were treated with Cd as cadmium chloride (CdCl2, 5 mg/ kg bw, PO) and pre-administered with GSP (100 mg/kg bw, PO) 90 min before the Cd intoxication for 4 weeks. Our results demonstrate a significant increase in the levels of cardiac troponins T and I (cTnT & I), cardiac serum markers, lipid peroxidative markers and plasma total cholesterol (TC), triglycerides (TG), phospholipids (PL) and free fatty acids (FFA). Cd induced oxidative stress decreased the levels of mitochondrial Krebs cycle enzymes as well as the respiratory chain enzyme activities and altered the levels of cardiac enzymatic and non-enzymatic antioxidants. The inflammatory (NF-kB, NO, TNF-α, IL-6), apoptotic markers (caspase 3, cytochrome C, Bax, Bcl-2), membrane bound ATPases and antioxidant Nrf2 (HO-1, keap1) markers were also measured in the control and experimental rats. All these alterations caused by Cd could be lessened by the pre-supplementation of GSP. The pre-administration of GSP significantly increased the activities of mitochondrial and respiratory chain enzymes, reduced the levels of cardio-oxidative stress markers in Cd-treated rats, which examines the stress stabilizing action of GSP. GSP also prevented the cytochrome C release, inhibited the caspase activation and maintained the ratio of Bcl-2/Bax by its free radical scavenging ability. Nrf2 expression was transiently increased while the impaired cardiac markers were restored near to their basal levels by the pre-treatment with GSP in Cd intoxicated rats. The cardioprotective nature of the GSP was further fortified by our light microscopic and ultra structural findings. Overall, our results suggest

  19. Use of ECG and Other Simple Non-Invasive Tools to Assess Pulmonary Hypertension

    PubMed Central

    Kovacs, Gabor; Avian, Alexander; Foris, Vasile; Tscherner, Maria; Kqiku, Xhylsime; Douschan, Philipp; Bachmaier, Gerhard; Olschewski, Andrea; Matucci-Cerinic, Marco; Olschewski, Horst

    2016-01-01

    Background There is a broad consensus that pulmonary hypertension (PH) is to be diagnosed by right heart catheterization (RHC) and that the most important non-invasive tool is echocardiography. However, the role of simple non-invasive tools in the work-up of PH is not clearly defined. We hypothesized that the use of simple non-invasive techniques may help to guide important decisions in the diagnostics of pulmonary hypertension. Objectives We aimed to develop an algorithm with the use of simple, non-invasive tools in order to identify patients with very high or very low likelihood of PH. Methods We retrospectively analyzed all consecutive patients undergoing RHC between 2005 and 2010 in our center and performed logistic regression of simple non-invasive parameters regarding detection and exclusion of PH and derived a two-step algorithm. In a prospective study we evaluated this algorithm between 2011 and 2013. Results The retrospective cohort consisted of n = 394 patients of which 49% presented with PH. Right axis deviation in the ECG was present in 90/394 patients and had a positive predictive value (PPV) of 93% for PH. The combination of non-right axis deviation, N-terminal pro brain natriuretic peptide (NT-proBNP)<333pg/ml, arterial oxygen saturation (SO2)≥95.5% and WHO functional class I-II was present in 69/394 patients and excluded PH with a negative predictive value (NPV) of 96%. The prospective study confirmed these results in a cohort of n = 168 patients (PPV:92%, NPV:97%). Taken together, simple non-invasive tools allowed a prediction regarding the presence or absence of PH in 42% of patients with suspected PH. Conclusion ECG, NT-proBNP, SO2 and WHO functional class may predict the presence or absence of PH in almost half of the patients with suspected PH, suggesting an important role for these variables in the work-up of patients at risk for PH. Clinical Trial Registration NCT01607502 PMID:28030578

  20. Measuring cardiac autonomic nervous system (ANS) activity in children.

    PubMed

    van Dijk, Aimée E; van Lien, René; van Eijsden, Manon; Gemke, Reinoud J B J; Vrijkotte, Tanja G M; de Geus, Eco J

    2013-04-29

    The autonomic nervous system (ANS) controls mainly automatic bodily functions that are engaged in homeostasis, like heart rate, digestion, respiratory rate, salivation, perspiration and renal function. The ANS has two main branches: the sympathetic nervous system, preparing the human body for action in times of danger and stress, and the parasympathetic nervous system, which regulates the resting state of the body. ANS activity can be measured invasively, for instance by radiotracer techniques or microelectrode recording from superficial nerves, or it can be measured non-invasively by using changes in an organ's response as a proxy for changes in ANS activity, for instance of the sweat glands or the heart. Invasive measurements have the highest validity but are very poorly feasible in large scale samples where non-invasive measures are the preferred approach. Autonomic effects on the heart can be reliably quantified by the recording of the electrocardiogram (ECG) in combination with the impedance cardiogram (ICG), which reflects the changes in thorax impedance in response to respiration and the ejection of blood from the ventricle into the aorta. From the respiration and ECG signals, respiratory sinus arrhythmia can be extracted as a measure of cardiac parasympathetic control. From the ECG and the left ventricular ejection signals, the preejection period can be extracted as a measure of cardiac sympathetic control. ECG and ICG recording is mostly done in laboratory settings. However, having the subjects report to a laboratory greatly reduces ecological validity, is not always doable in large scale epidemiological studies, and can be intimidating for young children. An ambulatory device for ECG and ICG simultaneously resolves these three problems. Here, we present a study design for a minimally invasive and rapid assessment of cardiac autonomic control in children, using a validated ambulatory device (1-5), the VU University Ambulatory Monitoring System (VU

  1. Establishing the diagnosis of inverted stress cardiomyopathy in a patient with cardiac arrest during general anesthesia: a potential role of myocardial strain?

    PubMed

    Cvorovic, Vojkan; Stankovic, Ivan; Panic, Milos; Stipac, Alja Vlahovic; Zivkovic, Aleksandra; Neskovic, Aleksandar N; Putnikovic, Biljana

    2013-07-01

    In cardiac arrest survivors, postresuscitation myocardial stunning usually presents as either global left ventricular dysfunction or regional dyssynergy including the various forms of stress cardiomyopathy, in which rare variants may be difficult to diagnose. We present a patient with cardiac arrest during general anesthesia, in whom speckle tracking-derived myocardial strain helped to distinguish between the inverted variant of stress cardiomyopathy and global postresuscitation myocardial stunning.

  2. Impact of high-sensitivity cardiac troponin on use of coronary angiography, cardiac stress testing, and time to discharge in suspected acute myocardial infarction

    PubMed Central

    Twerenbold, Raphael; Jaeger, Cedric; Rubini Gimenez, Maria; Wildi, Karin; Reichlin, Tobias; Nestelberger, Thomas; Boeddinghaus, Jasper; Grimm, Karin; Puelacher, Christian; Moehring, Berit; Pretre, Gil; Schaerli, Nicolas; Campodarve, Isabel; Rentsch, Katharina; Steuer, Stephan; Osswald, Stefan; Mueller, Christian

    2016-01-01

    Aims High-sensitivity cardiac troponin (hs-cTn) assays provide higher diagnostic accuracy for acute myocardial infarction (AMI) when compared with conventional assays, but may result in increased use of unnecessary coronary angiographies due to their increased detection of cardiomyocyte injury in conditions other than AMI. Methods and results We evaluated the impact of the clinical introduction of high-sensitivity cardiac troponin T (hs-cTnT) on the use of coronary angiography, stress testing, and time to discharge in 2544 patients presenting with symptoms suggestive of AMI to the emergency department (ED) within a multicentre study either before (1455 patients) or after (1089 patients) hs-cTnT introduction. Acute myocardial infarction was more often the clinical discharge diagnosis after hs-cTnT introduction (10 vs. 14%, P < 0.001), while unstable angina less often the clinical discharge diagnosis (14 vs. 9%, P = 0.007). The rate of coronary angiography was similar before and after the introduction of hs-cTnT (23 vs. 23%, P = 0.092), as was the percentage of coronary angiographies showing no stenosis (11 vs. 7%, P = 0.361). In contrast, the use of stress testing was substantially reduced from 29 to 19% (P < 0.001). In outpatients, median time to discharge from the ED decreased by 79 min (P < 0.001). Mean total costs decreased by 20% in outpatients after the introduction of hs-cTnT (P = 0.002). Conclusion The clinical introduction of hs-cTn does not lead to an increased or inappropriate use of coronary angiography. Introduction of hs-cTn is associated with an improved rule-out process and thereby reduces the need for stress testing and time to discharge. Clinical Trial Registration Information www.clinicaltrials.gov. Identifier, NCT00470587. PMID:27357358

  3. Non-invasive Assessment of Cerebral Blood Flow and Oxygen Metabolism in Neonates during Hypothermic Cardiopulmonary Bypass: Feasibility and Clinical Implications

    PubMed Central

    Ferradal, Silvina L.; Yuki, Koichi; Vyas, Rutvi; Ha, Christopher G.; Yi, Francesca; Stopp, Christian; Wypij, David; Cheng, Henry H.; Newburger, Jane W.; Kaza, Aditya K.; Franceschini, Maria A.; Kussman, Barry D.; Grant, P. Ellen

    2017-01-01

    The neonatal brain is extremely vulnerable to injury during periods of hypoxia and/or ischemia. Risk of brain injury is increased during neonatal cardiac surgery, where pre-existing hemodynamic instability and metabolic abnormalities are combined with long periods of low cerebral blood flow and/or circulatory arrest. Our understanding of events associated with cerebral hypoxia-ischemia during cardiopulmonary bypass (CPB) remains limited, largely due to inadequate tools to quantify cerebral oxygen delivery and consumption non-invasively and in real-time. This pilot study aims to evaluate cerebral blood flow (CBF) and oxygen metabolism (CMRO2) intraoperatively in neonates by combining two novel non-invasive optical techniques: frequency-domain near-infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS). CBF and CMRO2 were quantified before, during and after deep hypothermic cardiopulmonary bypass (CPB) in nine neonates. Our results show significantly decreased CBF and CMRO2 during hypothermic CPB. More interestingly, a change of coupling between both variables is observed during deep hypothermic CPB in all subjects. Our results are consistent with previous studies using invasive techniques, supporting the concept of FD-NIRS/DCS as a promising technology to monitor cerebral physiology in neonates providing the potential for individual optimization of surgical management. PMID:28276534

  4. Fetal DNA in maternal plasma: application to non-invasive blood group genotyping of the fetus.

    PubMed

    Lo, Y M

    2001-06-01

    The non-invasive determination of fetal genetic characteristics, including blood group types, is a long-sought goal of modern genetics. Previous work on the use of fetal cells in maternal blood has been hampered by the rarity of such cells. The recent discovery of cell-tree fetal DNA in maternal blood has opened up new possibilities for non-invasive prenatal diagnosis. It is particularly useful that fetal DNA is present in relatively high concentrations in maternal plasma, making its robust detection possible using modern technology. Large-scale clinical trials and standardization of protocols still need to be carried out. However, there is optimism that the accurate and safe prenatal determination of fetal blood group types may be achieved in routine clinical practice in the near future.

  5. Fatal brain gas embolism during non-invasive positive pressure ventilation

    PubMed Central

    Rivara, Claire B; Chevrolet, Jean-Claude; Gasche, Yvan; Charbonney, Emmanuel

    2008-01-01

    Gas embolism is a dreaded complication following invasive medical procedures, traumatic lung injury and decompression accidents. We report a case of fatal gas embolism following the use of non-invasive ventilation (NIV) with bilevel positive airway pressure (BiPAP). The patient initially underwent left bronchial artery embolisation for massive haemoptysis in the context of severe tuberculotic sequels. Under NIV and after heavy coughing he became hemiparetic and his level of consciousness suddenly dropped. Computed tomography of the brain showed multiple air embolism and ischaemic lesions were confirmed by magnetic resonance imaging. Echocardiographic investigations showed no intracardiac defect. Vasculo-pulmonary abnormalities in the context of heavy coughing and non-invasive ventilation may have played a major role in the occurrence of this event. New neurological events in a patient with tuberculotic sequels or any known vascular pulmonary abnormalities and NIV should raise the suspicion of brain gas embolism. PMID:21716825

  6. Single core-shell nanoparticle probes for non-invasive magnetic force microscopy.

    PubMed

    Uhlig, Tino; Wiedwald, Ulf; Seidenstücker, Axel; Ziemann, Paul; Eng, Lukas M

    2014-06-27

    We present an easy, fast and reliable method for the preparation of magnetic force microscopy (MFM) probes based on single Co nanoparticles (NPs). Due to their dipolar character, these magnetic probes open up a new approach for quantitative and non-invasive MFM measurements on the nanometer length scale. To guarantee long-term stability of these tips under ambient conditions, an ultrathin protecting Au shell was grown around the Co NPs through photochemical deposition. Single magnetic particles were firmly attached to standard silicon AFM tips using bifunctional self-assembling molecules. Such probes were tested on longitudinal magnetic recording media and compared to the results as recorded with conventional thin-film MFM tips. Easy data interpretation of the magnetic nanoparticle probes in a point dipole model is shown. Our nanoparticle tips provide excellent endurance for MFM recording, enable non-invasive probing while maintaining a high sensitivity, resolution, and reproducibility.

  7. Magneto-Electric Nano-Particles for Non-Invasive Brain Stimulation

    PubMed Central

    Yue, Kun; Guduru, Rakesh; Hong, Jeongmin; Liang, Ping; Nair, Madhavan; Khizroev, Sakhrat

    2012-01-01

    This paper for the first time discusses a computational study of using magneto-electric (ME) nanoparticles to artificially stimulate the neural activity deep in the brain. The new technology provides a unique way to couple electric signals in the neural network to the magnetic dipoles in the nanoparticles with the purpose to enable a non-invasive approach. Simulations of the effect of ME nanoparticles for non-invasively stimulating the brain of a patient with Parkinson's Disease to bring the pulsed sequences of the electric field to the levels comparable to those of healthy people show that the optimized values for the concentration of the 20-nm nanoparticles (with the magneto-electric (ME) coefficient of 100 V cm−1 Oe−1 in the aqueous solution) is 3×106 particles/cc, and the frequency of the externally applied 300-Oe magnetic field is 80 Hz. PMID:22957042

  8. A new microtomographic technique for non-invasive evaluation of the bone structure around implants.

    PubMed

    Sennerby, L; Wennerberg, A; Pasop, F

    2001-02-01

    A new X-ray microtomographic technique for non-invasive assessment of the structure of bone surrounding implants was tested. Three titanium microimplants retrieved directly (n = 2) or 6 months (n = 1) after insertion in 3 patients were used as test samples. Two samples were used dry and one was embedded in plastic resin prior to microtomography. The technique provided high-resolution consecutive cross-sectional X-ray images of the specimens with a slice-to-slice distance of 4.4 to 11.0 microns. The pictures could be imported into an image analysing software with which semiautomatic quantitative measurement of the bone area and three-dimensional images of the specimens could be made. It is suggested that the technique may be used for non-invasive assessment of the bone structure around implants. Further studies are needed to evaluate the accuracy of the technique, for instance by comparing tomographic sections with histologic ones.

  9. Non-invasive imaging using reporter genes altering cellular water permeability

    NASA Astrophysics Data System (ADS)

    Mukherjee, Arnab; Wu, Di; Davis, Hunter C.; Shapiro, Mikhail G.

    2016-12-01

    Non-invasive imaging of gene expression in live, optically opaque animals is important for multiple applications, including monitoring of genetic circuits and tracking of cell-based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatiotemporal resolution. However, existing MRI reporter genes based on metalloproteins or chemical exchange probes are limited by their reliance on metals or relatively low sensitivity. Here we introduce a new class of MRI reporters based on the human water channel aquaporin 1. We show that aquaporin overexpression produces contrast in diffusion-weighted MRI by increasing tissue water diffusivity without affecting viability. Low aquaporin levels or mixed populations comprising as few as 10% aquaporin-expressing cells are sufficient to produce MRI contrast. We characterize this new contrast mechanism through experiments and simulations, and demonstrate its utility in vivo by imaging gene expression in tumours. Our results establish an alternative class of sensitive, metal-free reporter genes for non-invasive imaging.

  10. Non-invasive assessment of bleeding pulmonary artery aneurysms due to Behçet disease.

    PubMed

    Greene, R M; Saleh, A; Taylor, A K; Callaghan, M; Addis, B J; Nzewi, O C; van Zyl, W V

    1998-01-01

    Because of its ability to depict intravascular, intramural, and extramural pathology, non-invasive imaging is well suited to assessing life-threatening hemoptysis that may complicate Behçet disease. We made exclusive use of CT angiography supplemented by MR to identify pulmonary thromboembolism, mediastinal lymphadenopathy, and bilateral pulmonary artery aneurysms with signs of previous unilateral rupture. Two-dimensional reformatted CT images provided surgeons with a road map of upstream and downstream vascular relationships prior to aneurysm resection. Imaging findings were confirmed by surgery and pathology. Non-invasive imaging proved to be a useful alternative to standard catheter arteriography in the preoperative assessment of hemoptysis in this patient with Behçet disease.

  11. Limitations and opportunities of non-invasive liver stiffness measurement in children

    PubMed Central

    Engelmann, Guido; Quader, Jasmin; Teufel, Ulrike; Schenk, Jens Peter

    2017-01-01

    Changes in liver structure are an important issue in chronic hepatopathies. Until the end of the 20th century, these changes could only be determined by histological analyses of a liver specimen obtained via biopsy. The well-known limitations of this technique (i.e., pain, bleeding and the need for sedation) have precluded its routine use in follow-up of patients with liver diseases. However, the introduction of non-invasive technologies, such as ultrasound and magnetic resonance imaging, for measurement of liver stiffness as an indirect marker of fibroses has changed this situation. Today, several non-invasive tools are available to physicians to estimate the degree of liver fibrosis by analysing liver stiffness. This review describes the currently available tools for liver stiffness determination that are applicable to follow-up of liver fibrosis/cirrhosis with established clinical use in children, and discusses their features in comparison to the “historical” tools. PMID:28357028

  12. Characterization of the Tumor Microenvironment and Tumor–Stroma Interaction by Non-invasive Preclinical Imaging

    PubMed Central

    Ramamonjisoa, Nirilanto; Ackerstaff, Ellen

    2017-01-01

    Tumors are often characterized by hypoxia, vascular abnormalities, low extracellular pH, increased interstitial fluid pressure, altered choline-phospholipid metabolism, and aerobic glycolysis (Warburg effect). The impact of these tumor characteristics has been investigated extensively in the context of tumor development, progression, and treatment response, resulting in a number of non-invasive imaging biomarkers. More recent evidence suggests that cancer cells undergo metabolic reprograming, beyond aerobic glycolysis, in the course of tumor development and progression. The resulting altered metabolic content in tumors has the ability to affect cell signaling and block cellular differentiation. Additional emerging evidence reveals that the interaction between tumor and stroma cells can alter tumor metabolism (leading to metabolic reprograming) as well as tumor growth and vascular features. This review will summarize previous and current preclinical, non-invasive, multimodal imaging efforts to characterize the tumor microenvironment, including its stromal components and understand tumor–stroma interaction in cancer development, progression, and treatment response. PMID:28197395

  13. Imaging and finite element analysis: a methodology for non-invasive characterization of aortic tissue.

    PubMed

    Flamini, Vittoria; Creane, Arthur P; Kerskens, Christian M; Lally, Caitríona

    2015-01-01

    Characterization of the mechanical properties of arterial tissues usually involves an invasive procedure requiring tissue removal. In this work we propose a non-invasive method to perform a biomechanical analysis of cardiovascular aortic tissue. This method is based on combining medical imaging and finite element analysis (FEA). Magnetic resonance imaging (MRI) was chosen since it presents relatively low risks for human health. A finite element model was created from the MRI images and loaded with systolic physiological pressures. By means of an optimization routine, the structural material properties were changed until average strains matched those measured by MRI. The method outlined in this work produced an estimate of the in situ properties of cardiovascular tissue based on non-invasive image datasets and finite element analysis.

  14. [CD147 expression in non-invasive and invasive breast carcinoma].

    PubMed

    Nagashima, Saki; Sakurai, Kenichi; Suzuki, Shuhei; Hara, Yukiko; Maeda, Tetsuyo; Hirano, Tomohisa; Enomoto, Katsuhisa; Amano, Sadao; Koshinaga, Tsugumichi

    2014-10-01

    CD147 is a multifunctional membrane glycoprotein involved in tumor invasion, and is overexpressed in many solid tumors. However, the role of CD147 in breast cancer is not well understood. The aim of this study was to evaluate CD147 expression in non-invasive and invasive ductal carcinomas. We recruited 156 breast cancer patients who underwent radical operations at our hospital up until 2002. We performed immunohistochemistry on their tumor specimens, and compared these data with clinicopathological factors. We divided the patients into two groups: group A was comprised of non-invasive ductal carcinomas and group B, invasive ductal carcinomas. The CD147-positive rate was 62.8% for all patients and was higher in group B than group A. In all cases, the CD147-positive rate correlated with clinical stage, number of metastatic lymph nodes, and tumor size. These results implied that CD147 may be involved in the process of breast cancer invasion.

  15. Reflection infrared spectroscopy for the non-invasive in situ study of artists' pigments

    NASA Astrophysics Data System (ADS)

    Miliani, C.; Rosi, F.; Daveri, A.; Brunetti, B. G.

    2012-02-01

    The potential of fibre optic reflection infrared spectroscopy for the non-invasive identification of artists' pigments is presented. Sixteen different carbonate, sulphate and silicate-based pigments are taken into account considering their wide use during the history of art and their infrared optical properties. The infrared distortions mainly generated by the specular reflection are discussed on the basis of experimental measurements carried out on reference samples. The study on pure materials permitted the definition of marker bands, mainly combination and overtone modes, enhanced by the diffuse reflection component of the light, functional for the non-invasive pigment identification in real artworks. Several case studies are reported, including wall, easel, canvas paintings and manuscripts from ancient to modern art demonstrating the strengths of the technique on the identification of pigments even in the presence of complex mixtures of both organic (binders, varnishes) and inorganic (supports, fillers and other pigments) compounds.

  16. Non-invasive Human Brain Stimulation in Cognitive Neuroscience: A Primer.

    PubMed

    Parkin, Beth L; Ekhtiari, Hamed; Walsh, Vincent F

    2015-09-02

    The use of non-invasive brain stimulation is widespread in studies of human cognitive neuroscience. This has led to some genuine advances in understanding perception and cognition, and has raised some hopes of applying the knowledge in clinical contexts. There are now several forms of stimulation, the ability to combine these with other methods, and ethical questions that are special to brain stimulation. In this Primer, we aim to give the users of these methods a starting point and perspective from which to view the key questions and usefulness of the different forms of non-invasive brain stimulation. We have done so by taking a critical view of recent highlights in the literature, selected case studies to illustrate the elements necessary and sufficient for good experiments, and pointed to questions and findings that can only be addressed using interference methods.

  17. Developing a confocal acoustic holography microscope for non-invasive 3D temperature and composition measurements.

    PubMed

    Herring, Rodney A; Jacquemin, Peter; Sawicka, Barbara D; Atalick, Stefan

    2009-06-01

    A confocal acoustic holography microscope (CAHM) has been designed, simulated and partially verified experimentally to take holograms for non-invasive, three-dimensional measurements of a specimen's refractive indices from one view point. The designed and simulated prototype CAHM used a frequency of 2.25 MHz and measured sound speed changes of 16 m/s, temperature changes of 5 degrees C and had a spatial resolution of 660 microm. With future improvements utilizing the latest technologies such as two-dimensional array detectors, Micro-Electro-Mechanical Systems (MEMS), and acoustic lenses, resolutions of 1m/s, 0.5 degrees C, and 150 microm are expected. The CAHM is expected to have many useful applications, including non-invasive mass and heat transfer measurements in fluids and materials and as a medical diagnostic tool to non-intrusively visualize compositions and temperatures within the human body.

  18. Non-invasive antidromic neurostimulation: a simple effective method for improving bladder storage.

    PubMed

    Walsh, I K; Thompson, T; Loughridge, W G; Johnston, S R; Keane, P F; Stone, A R

    2001-01-01

    Patients with intractably diminished bladder storage function are encountered frequently by neurourologists, occasionally requiring reconstructive surgery for appropriate resolution. Although sacral neuromodulation is a recognized effective therapeutic modality, present techniques are technically demanding, invasive, and expensive. This study investigated the effect of non-invasive third sacral nerve (S3) stimulation on bladder activity during filling cystometry. One hundred forty-six patients underwent standard urodynamic filling cystometry that was then immediately repeated. Patients in the study group (n = 74) received antidromic transcutaneous sacral neurostimulation during the second fill and the control group (n = 72) underwent a second fill without neurostimulation. A statistically significant increase in bladder storage capacity without a corresponding rise in detrusor pressure was observed in the neurostimulated patients. This improvement in functional capacity is an encouraging finding that further supports the use of this non-invasive treatment modality in clinical practice.

  19. Rheoencephalography (REG) as a Non-Invasive Monitoring Alternative for the Assessment of Brain Blood Flow

    DTIC Science & Technology

    2004-09-01

    arterial pressure of 40 mmHg, and then held there until experimental intervention, resuscitation, decompensation or death occurred. The experiment was...regulations relating to animals and experiments involving animals and adheres to principles stated in the Guide for the Care and Use of Laboratory Animals...Rheoencephalography (REG) as a Non-Invasive Monitoring Alternative for the Assessment of Brain Blood Flow P3 - 12 RTO-MP-HFM-109 experiments we

  20. Diffuse correlation spectroscopy for non-invasive, micro-vascular cerebral blood flow measurement

    PubMed Central

    Durduran, Turgut; Yodh, Arjun G.

    2013-01-01

    Diffuse correlation spectroscopy (DCS) uses the temporal fluctuations of near-infrared (NIR) light to measure cerebral blood flow (CBF) non-invasively. Here, we provide a brief history of DCS applications in brain with an emphasis on the underlying physical ideas, common instrumentation and validation. Then we describe recent clinical research that employs DCS-measured CBF as a biomarker of patient well-being, and as an indicator of hemodynamic and metabolic response to functional stimuli. PMID:23770408

  1. A non-invasive head-holding device for chronic neural recordings in awake behaving monkeys

    PubMed Central

    Amemori, Satoko; Amemori, Ken-ichi; Cantor, Margaret L.; Graybiel, Ann M.

    2014-01-01

    Background We have developed a novel head-holding device for behaving non-human primates that affords stability suitable for reliable chronic electrophysiological recording experiments. The device is completely non-invasive, and thus avoids the risk of infection and other complications that can occur with the use of conventional, surgically implanted head-fixation devices. New method The device consists of a novel non-invasive head mold and bar clamp holder, and is customized to the shape of each monkey’s head. The head-holding device that we introduce, combined with our recording system and reflection-based eye-tracking system, allows for chronic behavioral experiments and single-electrode or multi-electrode recording, as well as manipulation of brain activity. Results and comparison with existing methods With electrodes implanted chronically in multiple brain regions, we could record neural activity from cortical and subcortical structures with stability equal to that recorded with conventional head-post fixation. Consistent with the non-invasive nature of the device, we could record neural signals for more than two years with a single implant. Importantly, the monkeys were able to hold stable eye fixation positions while held by this device, demonstrating the possibility of analyzing eye movement data with only the gentle restraint imposed by the non-invasive head-holding device. Conclusions We show that the head-holding device introduced here can be extended to the head holding of smaller animals, and note that it could readily be adapted for magnetic resonance brain imaging over extended periods of time. PMID:25448381

  2. Non-invasive electric current stimulation for restoration of vision after unilateral occipital stroke.

    PubMed

    Gall, Carolin; Silvennoinen, Katri; Granata, Giuseppe; de Rossi, Francesca; Vecchio, Fabrizio; Brösel, Doreen; Bola, Michał; Sailer, Michael; Waleszczyk, Wioletta J; Rossini, Paolo M; Tatlisumak, Turgut; Sabel, Bernhard A

    2015-07-01

    Occipital stroke often leads to visual field loss, for which no effective treatment exists. Little is known about the potential of non-invasive electric current stimulation to ameliorate visual functions in patients suffering from unilateral occipital stroke. One reason is the traditional thinking that visual field loss after brain lesions is permanent. Since evidence is available documenting vision restoration by means of vision training or non-invasive electric current stimulation future studies should also consider investigating recovery processes after visual cortical strokes. Here, protocols of repetitive transorbital alternating current stimulation (rtACS) and transcranial direct current stimulation (tDCS) are presented and the European consortium for restoration of vision (REVIS) is introduced. Within the consortium different stimulation approaches will be applied to patients with unilateral occipital strokes resulting in homonymous hemianopic visual field defects. The aim of the study is to evaluate effects of current stimulation of the brain on vision parameters, vision-related quality of life, and physiological parameters that allow concluding about the mechanisms of vision restoration. These include EEG-spectra and coherence measures, and visual evoked potentials. The design of stimulation protocols involves an appropriate sham-stimulation condition and sufficient follow-up periods to test whether the effects are stable. This is the first application of non-invasive current stimulation for vision rehabilitation in stroke-related visual field deficits. Positive results of the trials could have far-reaching implications for clinical practice. The ability of non-invasive electrical current brain stimulation to modulate the activity of neuronal networks may have implications for stroke rehabilitation also in the visual domain.

  3. Comparing a non-invasive hemodynamic monitor with minimally invasive monitoring during major open abdominal surgery

    PubMed Central

    Ong, Lawrence; Liu, Hong

    2014-01-01

    Abstract As part of the enhanced recovery after surgery (ERAS) protocol, the goal-directed fluid management with hemodynamic monitoring can effectively guide perioperative fluid use and significantly improve the outcomes in high-risk patients undergoing major surgeries. Several minimally invasive and non-invasive monitoring devices are commercially available for clinical use. As part of an internal evaluation, we reported the results from three different hemodynamic monitoring devices used in a patient undergoing a major abdominal surgery. PMID:25050116

  4. Non-invasive, non-radiological quantification of anteroposterior knee joint ligamentous laxity

    PubMed Central

    Russell, D. F.; Deakin, A. H.; Fogg, Q. A.; Picard, F.

    2013-01-01

    Objectives We performed in vitro validation of a non-invasive skin-mounted system that could allow quantification of anteroposterior (AP) laxity in the outpatient setting. Methods A total of 12 cadaveric lower limbs were tested with a commercial image-free navigation system using trackers secured by bone screws. We then tested a non-invasive fabric-strap system. The lower limb was secured at 10° intervals from 0° to 60° of knee flexion and 100 N of force was applied perpendicular to the tibia. Acceptable coefficient of repeatability (CR) and limits of agreement (LOA) of 3 mm were set based on diagnostic criteria for anterior cruciate ligament (ACL) insufficiency. Results Reliability and precision within the individual invasive and non-invasive systems was acceptable throughout the range of flexion tested (intra-class correlation coefficient 0.88, CR 1.6 mm). Agreement between the two systems was acceptable measuring AP laxity between full extension and 40° knee flexion (LOA 2.9 mm). Beyond 40° of flexion, agreement between the systems was unacceptable (LOA > 3 mm). Conclusions These results indicate that from full knee extension to 40° flexion, non-invasive navigation-based quantification of AP tibial translation is as accurate as the standard validated commercial system, particularly in the clinically and functionally important range of 20° to 30° knee flexion. This could be useful in diagnosis and post-operative evaluation of ACL pathology. Cite this article: Bone Joint Res 2013;2:233–7. PMID:24184443

  5. Fetal cells in maternal blood: state of the art for non-invasive prenatal diagnosis.

    PubMed

    Ho, S S; O'Donoghue, K; Choolani, M

    2003-09-01

    In Singapore, 1 in 5 pregnancies occur in mothers > 35 years old and genetic diseases, such as thalassaemia, are common. Current methods for the diagnosis of aneuploidy and monogenic disorders require invasive testing by amniocentesis, chorion villus biopsy or fetal blood sampling. These tests carry a procedure-related risk of miscarriage that is unacceptable to many couples. Development of non-invasive methods for obtaining intact fetal cells would allow accurate prenatal diagnosis for aneuploidy and single gene disorders, without the attendant risks associated with invasive testing, and would increase the uptake of prenatal diagnosis by women at risk. Isolation of fetal erythroblasts from maternal blood should allow accurate non-invasive prenatal diagnosis of both aneuploidies and monogenic disorders. Expression of gamma-globin in maternal erythroblasts and the inability to locate fetal erythroblasts reliably in all pregnancies have prevented its clinical application. In the absence of a highly specific fetal cell marker, enrichment, identification and diagnosis--the 3 components of non-invasive prenatal diagnosis--have clearly defined objectives. Since fetal cells are rare in maternal blood, the sole purpose of enrichment is yield--to recover as many fetal cells as possible--even if purity is compromised at this stage. In contrast, the primary goal of identification is specificity; absolute certainty of fetal origin is required at this stage if the ultimate objective of diagnosis, accuracy, is to be achieved. This review summarises the current state of the art of non-invasive prenatal diagnosis using fetal erythroblasts enriched from maternal blood.

  6. Development of Non-Invasive Deep Tissue pH Sensor.

    DTIC Science & Technology

    1995-10-01

    effort has demonstrated the feasibility of measuring deep tissue pH using near infrared reflection spectroscopy coupled with partial least squares...LIST OF FIGURES PAGE Figure 1. Diagram of Near- Infrared Fiber-optic Spectroscopy 8 System for Non-Contact pH Measurement in Human or Animal Tissue Figure...delivery that the tissue pH measurement provides. The ability to non-invasively measure tissue oxygenation using near- infrared spectroscopy has been

  7. Non-invasive Brain Stimulation, a Tool to Revert Maladaptive Plasticity in Neuropathic Pain

    PubMed Central

    Naro, Antonino; Milardi, Demetrio; Russo, Margherita; Terranova, Carmen; Rizzo, Vincenzo; Cacciola, Alberto; Marino, Silvia; Calabro, Rocco S.; Quartarone, Angelo

    2016-01-01

    Neuromodulatory effects of non-invasive brain stimulation (NIBS) have been extensively studied in chronic pain. A hypothetic mechanism of action would be to prevent or revert the ongoing maladaptive plasticity within the pain matrix. In this review, the authors discuss the mechanisms underlying the development of maladaptive plasticity in patients with chronic pain and the putative mechanisms of NIBS in modulating synaptic plasticity in neuropathic pain conditions. PMID:27512368

  8. Utility of Transcutaneous Capnography for Optimization of Non-Invasive Ventilation Pressures

    PubMed Central

    Gehrer, Simone; Pandey, Kamlesh V; Vaidya, Preyas J; Leuppi, Joerg D.; Tamm, Michael; Strobel, Werner

    2016-01-01

    Introduction Nocturnal Non-invasive Positive Pressure Ventilation (NPPV) is the treatment of choice in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous oxygen saturation measured with a pulse oximeter provides a surrogate measure of arterial oxygen saturation but does not completely reflect ventilation. Currently, Partial Pressure of Arterial (PaCO2) measured by arterial blood analysis is used for estimating the adequacy of ventilatory support and serves as the gold standard Aim To examine the safety, feasibility and utility of cutaneous capnography to re-titrate the non-invasive positive pressure ventilation settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Materials and Methods Twelve patients with chronic hypercapnic respiratory failure prospectively underwent complete polysomnography and cutaneous capnography measurement on the ear lobe. Non-invasive ventilation pressures were adjusted with the aim of normalizing cutaneous carbon dioxide or at least reducing it by 10 to 15 mmHg. Sensor drift for cutaneous carbon dioxide of 0.7 mmHg per hour was integrated in the analysis. Results Mean baseline cutaneous carbon dioxide was 45.4 ± 6.5 mmHg and drift corrected awake value was 45.1 ± 8.3 mmHg. The correlation of baseline cutaneous carbon dioxide and the corrected awake cutaneous carbon dioxide with arterial blood gas values were 0.91 and 0.85 respectively. Inspiratory positive airway pressures were changed in nine patients (75%) and expiratory positive airway pressures in eight patients (66%). Epworth sleepiness score before and after the study showed no change in five patients, improvement in six patients and deterioration in one patient. Conclusion Cutaneous capnography is feasible and permits the optimization of non-invasive ventilation pressure settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous cutaneous capnography might serve as

  9. Non-invasive blood glucose detection system based on conservation of energy method.

    PubMed

    Zhang, Yang; Zhu, Jian-Ming; Liang, Yong-Bo; Chen, Hong-Bo; Yin, Shi-Min; Chen, Zhen-Cheng

    2017-02-01

    The most common method used for minimizing the occurrence of diabetes complications is frequent glucose testing to adjust the insulin dose. However, using blood glucose (BG) meters presents a risk of infection. It is of great importance to develop non-invasive BG detection techniques. To realize high-accuracy, low-cost and continuous glucose monitoring, we have developed a non-invasive BG detection system using a mixed signal processor 430 (MSP430) microcontroller. This method is based on the combination of the conservation-of-energy method with a sensor integration module, which collects physiological parameters, such as the blood oxygen saturation (SPO2), blood flow velocity and heart rate. New methods to detect the basal metabolic rate (BMR) and BV are proposed, which combine the human body heat balance and characteristic signals of photoplethysmography as well dual elastic chambers theory. Four hundred clinical trials on real-time non-invasive BG monitoring under suitable experiment conditions were performed on different individuals, including diabetic patients, senior citizens and healthy adults. A multisensory information fusion model was applied to process these samples. The algorithm (we defined it as DCBPN algorithm) applied in the model combines a decision tree and back propagation neural network, which classifies the physiological and environmental parameters into three categories, and then establishes a corresponding prediction model for the three categories. The DCBPN algorithm provides an accuracy of 88.53% in predicting the BG of new samples. Thus, this system demonstrates a great potential to reliably detect BG values in a non-invasive setting.

  10. Non-invasive, Focused Ultrasound-Facilitated Gene Delivery for Optogenetics

    NASA Astrophysics Data System (ADS)

    Wang, Shutao; Kugelman, Tara; Buch, Amanda; Herman, Mathieu; Han, Yang; Karakatsani, Maria Eleni; Hussaini, S. Abid; Duff, Karen; Konofagou, Elisa E.

    2017-01-01

    Optogenetics, a widely used technique in neuroscience research, is often limited by its invasive nature of application. Here, we present a noninvasive, ultrasound-based technique to introduce optogenetic channels into the brain by temporarily opening the blood-brain barrier (BBB). We demonstrate the efficiency of the method developed and evaluate the bioactivity of the non-invasively introduced channelrhodopsin channels by performing stimulation in freely behaving mice.

  11. Outcome of the pancreatic remnant following segmental pancreatectomy for non-invasive intraductal papillary mucinous neoplasm

    PubMed Central

    Miller, Jacob R; Meyer, Juliana E; Waters, Joshua A; Al-Haddad, Mohammad; DeWitt, John; Sherman, Stuart; Lillemoe, Keith D; Schmidt, C Max

    2011-01-01

    Objectives Intraductual papillary mucinous neoplasms (IPMNs) are often multifocal and involve the entire pancreas. Because of the morbidity associated with total pancreatectomy, surgeons will perform segmental pancreatectomy, resecting only the most ‘threatening’ IPMN lesion(s). We sought to determine whether the presence of residual IPMN following segmental pancreatectomy for non-invasive IPMN increases the risk for subsequent development of invasive pancreatic cancer and decreases survival. Methods Data on patients undergoing segmental resection of non-invasive IPMN during the period 1991–2010 at a high-volume academic institution were prospectively accrued. Results Of 243 patients who underwent segmental resection for IPMN, 191 (79%) demonstrated non-invasive pathology. Of these, 153 (80%) showed the absence and 38 (20%) the presence of residual IPMN at the initial operation. Of the 38 patients with residual IPMN, eight had positive IPMN margins, 23 had radiographic evidence of IPMN, and seven had both. During a mean follow-up of 73 months, 31 (20%) of 153 patients without residual IPMN developed a new radiographic lesion consistent with IPMN and, of these, three (10%) were found to represent invasive cancer. One (3%) of 38 patients with residual IPMN developed invasive cancer. In summary, in 191 initially non-invasive cases of IPMN, four invasive cancers (2%) developed during follow-up. The mean progression-free interval in these four patients was 54 months (range: 20–99 months). Conclusions Compared with patients undergoing complete operative IPMN clearance, patients with residual IPMN after segmental pancreatectomy do not demonstrate increased risk for the development of invasive disease or reduced survival. In patients without residual IPMN who later develop new IPMN, the risk for invasive IPMN is increased. PMID:21999588

  12. Non-invasive, Focused Ultrasound-Facilitated Gene Delivery for Optogenetics

    PubMed Central

    Wang, Shutao; Kugelman, Tara; Buch, Amanda; Herman, Mathieu; Han, Yang; Karakatsani, Maria Eleni; Hussaini, S. Abid; Duff, Karen; Konofagou, Elisa E.

    2017-01-01

    Optogenetics, a widely used technique in neuroscience research, is often limited by its invasive nature of application. Here, we present a noninvasive, ultrasound-based technique to introduce optogenetic channels into the brain by temporarily opening the blood-brain barrier (BBB). We demonstrate the efficiency of the method developed and evaluate the bioactivity of the non-invasively introduced channelrhodopsin channels by performing stimulation in freely behaving mice. PMID:28059117

  13. Development of a Novel, Non-Invasive Diagnostic Test for Prostate Cancer

    DTIC Science & Technology

    2007-01-01

    Invasive Diagnostic Test for Prostate Cancer PRINCIPAL INVESTIGATOR: Robert Gardiner, M.D...Novel, Non-Invasive Diagnostic Test for Prostate Cancer 5b. GRANT NUMBER W81XWH-05-1-0092 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...patients with prostate cancer so that transrectal ultrasound guided biopsies can be restricted to men harboring PCa. Our broad strategy will involve

  14. Research of transmissive near infrared spectroscopy for non-invasive blood glucose measurement

    NASA Astrophysics Data System (ADS)

    Yang, Wenming; Liao, Ningfang; Li, Yasheng; Shao, Liwei; Huang, Dehuang

    2016-10-01

    Near infrared (NIR) has prospectively applied in non-invasive blood glucose measurement due to glucose absorption among the 1.0-2.5m spectral bands. However, this significant technology is hard to be developed because of other blood components and low signal-to-noise ratio (SNR). In this work, we presented a non-invasive glucose measurement system using Fourier transform spectrometer which will work in fingertips or other human body tissues. A refrigerated InGaAs detector with high quantum efficiency performing well in the range of 1.0-1.7μm wavelength is used to acquire transmissive radiation. Preliminary experiment investigations were set up to test glucose levels of aqueous solutions with different concentrations. The analytical modeling of the interferogram data is based on arithmetic Fourier transform and supported by the curvilineal characterization. Experimental results show the variation of light intensity among different glucose concentrations and emphasize the obvious absorption of glucose in NIR wave-range. This study confirms the suitability that NIR can be developed in non-invasive glucose measurement.

  15. Non-invasive Markers of Liver Fibrosis: Adjuncts or Alternatives to Liver Biopsy?

    PubMed Central

    Chin, Jun L.; Pavlides, Michael; Moolla, Ahmad; Ryan, John D.

    2016-01-01

    Liver fibrosis reflects sustained liver injury often from multiple, simultaneous factors. Whilst the presence of mild fibrosis on biopsy can be a reassuring finding, the identification of advanced fibrosis is critical to the management of patients with chronic liver disease. This necessity has lead to a reliance on liver biopsy which itself is an imperfect test and poorly accepted by patients. The development of robust tools to non-invasively assess liver fibrosis has dramatically enhanced clinical decision making in patients with chronic liver disease, allowing a rapid and informed judgment of disease stage and prognosis. Should a liver biopsy be required, the appropriateness is clearer and the diagnostic yield is greater with the use of these adjuncts. While a number of non-invasive liver fibrosis markers are now used in routine practice, a steady stream of innovative approaches exists. With improvement in the reliability, reproducibility and feasibility of these markers, their potential role in disease management is increasing. Moreover, their adoption into clinical trials as outcome measures reflects their validity and dynamic nature. This review will summarize and appraise the current and novel non-invasive markers of liver fibrosis, both blood and imaging based, and look at their prospective application in everyday clinical care. PMID:27378924

  16. Non-invasive Diagnosis of Fibrosis in Non-alcoholic Fatty Liver Disease.

    PubMed

    Arora, Anil; Sharma, Praveen

    2012-06-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed as well as in developing countries. Its prevalence continues to rise currently affecting approximately 20-30% of adults and 10% of children in the United States. Non-alcoholic fatty liver disease represents a wide spectrum of conditions ranging from fatty liver, which in general follows a benign non-progressive clinical course, to non-alcoholic steatohepatitis (NASH), a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. Liver biopsy remains the gold standard for evaluating the degree of hepatic necroinflammation and fibrosis; however, several non-invasive investigations, such as serum biomarkers, have been developed to establish the diagnosis and also to evaluate treatment response. There has been a substantial development of non-invasive risk scores, biomarker panels, and radiological modalities to identify at risk patients with NAFLD without recourse to liver biopsy on a routine basis. Examples include combination of serum markers like NAFLD fibrosis score (NFS), BARD score, fibrometer, FIB4, and non-invasive tools like fibroscan which assess fibrosis in patients with NAFLD. Other markers of fibrosis that have been evaluated include high-sensitivity C-reactive protein, plasma pentraxin 3, interleukin-6, and cytokeratin-18. This review focuses on the methods currently available in daily clinical practice in hepatology and touches briefly on the potential future markers under investigation.

  17. SNP-based non-invasive prenatal testing detects sex chromosome aneuploidies with high accuracy

    PubMed Central

    Samango-Sprouse, Carole; Banjevic, Milena; Ryan, Allison; Sigurjonsson, Styrmir; Zimmermann, Bernhard; Hill, Matthew; Hall, Megan P.; Westemeyer, Margaret; Saucier, Jennifer; Demko, Zachary; Rabinowitz, Matthew

    2013-01-01

    Objective To develop a single nucleotide polymorphism- and informatics-based non-invasive prenatal test that detects sex chromosome aneuploidies early in pregnancy. Methods Fifteen aneuploid samples, including thirteen 45,X, two 47,XXY, and one 47,XYY, along with 185 euploid controls, were analyzed. Cell-free DNA was isolated from maternal plasma, amplified in a single multiplex PCR assay that targeted 19,488 polymorphic loci covering chromosomes 13, 18, 21, X, and Y, and sequenced. Sequencing results were analyzed using a Bayesian-based maximum likelihood statistical method to determine copy number of interrogated chromosomes, calculating sample-specific accuracies. Results Of the samples that passed a stringent quality control metric (93%), the algorithm correctly identified copy number at all five chromosomes in all 187 samples, for 934/935 correct calls as early as 9.4 weeks of gestation. We detected 45,X with 91.7% sensitivity (CI: 61.5-99.8%) and 100% specificity (CI: 97.9-100%), and 47,XXY and 47,XYY. The average calculated accuracy was 99.78%. Conclusion This method non-invasively detected 45,X, 47,XXY, and 47,XYY fetuses from cfDNA isolated from maternal plasma with high calculated accuracies, and thus offers a non-invasive method with the potential to function as a routine screen allowing for early prenatal detection of rarely diagnosed yet commonly occurring sex aneuploidies. PMID:23712453

  18. Promoting social plasticity in developmental disorders with non-invasive brain stimulation techniques

    PubMed Central

    Boggio, Paulo S.; Asthana, Manish K.; Costa, Thiago L.; Valasek, Cláudia A.; Osório, Ana A. C.

    2015-01-01

    Being socially connected directly impacts our basic needs and survival. People with deficits in social cognition might exhibit abnormal behaviors and face many challenges in our highly social-dependent world. These challenges and limitations are associated with a substantial economical and subjective impact. As many conditions where social cognition is affected are highly prevalent, more treatments have to be developed. Based on recent research, we review studies where non-invasive neuromodulatory techniques have been used to promote Social Plasticity in developmental disorders. We focused on three populations where non-invasive brain stimulation seems to be a promising approach in inducing social plasticity: Schizophrenia, Autism Spectrum Disorder (ASD) and Williams Syndrome (WS). There are still very few studies directly evaluating the effects of transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) in the social cognition of these populations. However, when considering the promising preliminary evidences presented in this review and the limited amount of clinical interventions available for treating social cognition deficits in these populations today, it is clear that the social neuroscientist arsenal may profit from non-invasive brain stimulation techniques for rehabilitation and promotion of social plasticity. PMID:26388712

  19. Non-invasive Diagnosis of Fibrosis in Non-alcoholic Fatty Liver Disease

    PubMed Central

    Arora, Anil; Sharma, Praveen

    2012-01-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed as well as in developing countries. Its prevalence continues to rise currently affecting approximately 20-30% of adults and 10% of children in the United States. Non-alcoholic fatty liver disease represents a wide spectrum of conditions ranging from fatty liver, which in general follows a benign non-progressive clinical course, to non-alcoholic steatohepatitis (NASH), a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. Liver biopsy remains the gold standard for evaluating the degree of hepatic necroinflammation and fibrosis; however, several non-invasive investigations, such as serum biomarkers, have been developed to establish the diagnosis and also to evaluate treatment response. There has been a substantial development of non-invasive risk scores, biomarker panels, and radiological modalities to identify at risk patients with NAFLD without recourse to liver biopsy on a routine basis. Examples include combination of serum markers like NAFLD fibrosis score (NFS), BARD score, fibrometer, FIB4, and non-invasive tools like fibroscan which assess fibrosis in patients with NAFLD. Other markers of fibrosis that have been evaluated include high-sensitivity C-reactive protein, plasma pentraxin 3, interleukin-6, and cytokeratin-18. This review focuses on the methods currently available in daily clinical practice in hepatology and touches briefly on the potential future markers under investigation. PMID:25755423

  20. Non-invasive pressure difference estimation from PC-MRI using the work-energy equation

    PubMed Central

    Donati, Fabrizio; Figueroa, C. Alberto; Smith, Nicolas P.; Lamata, Pablo; Nordsletten, David A.

    2015-01-01

    Pressure difference is an accepted clinical biomarker for cardiovascular disease conditions such as aortic coarctation. Currently, measurements of pressure differences in the clinic rely on invasive techniques (catheterization), prompting development of non-invasive estimates based on blood flow. In this work, we propose a non-invasive estimation procedure deriving pressure difference from the work-energy equation for a Newtonian fluid. Spatial and temporal convergence is demonstrated on in silico Phase Contrast Magnetic Resonance Image (PC-MRI) phantoms with steady and transient flow fields. The method is also tested on an image dataset generated in silico from a 3D patient-specific Computational Fluid Dynamics (CFD) simulation and finally evaluated on a cohort of 9 subjects. The performance is compared to existing approaches based on steady and unsteady Bernoulli formulations as well as the pressure Poisson equation. The new technique shows good accuracy, robustness to noise, and robustness to the image segmentation process, illustrating the potential of this approach for non-invasive pressure difference estimation. PMID:26409245

  1. Non-invasive, transient determination of the core temperature of a heat-generating solid body

    PubMed Central

    Anthony, Dean; Sarkar, Daipayan; Jain, Ankur

    2016-01-01

    While temperature on the surface of a heat-generating solid body can be easily measured using a variety of methods, very few techniques exist for non-invasively measuring the temperature inside the solid body as a function of time. Measurement of internal temperature is very desirable since measurement of just the surface temperature gives no indication of temperature inside the body, and system performance and safety is governed primarily by the highest temperature, encountered usually at the core of the body. This paper presents a technique to non-invasively determine the internal temperature based on the theoretical relationship between the core temperature and surface temperature distribution on the outside of a heat-generating solid body as functions of time. Experiments using infrared thermography of the outside surface of a thermal test cell in a variety of heating and cooling conditions demonstrate good agreement of the predicted core temperature as a function of time with actual core temperature measurement using an embedded thermocouple. This paper demonstrates a capability to thermally probe inside solid bodies in a non-invasive fashion. This directly benefits the accurate performance prediction and control of a variety of engineering systems where the time-varying core temperature plays a key role. PMID:27804981

  2. Continuous non-invasive monitoring improves blood pressure stability in upright position: randomized controlled trial.

    PubMed

    Benes, Jan; Simanova, Alena; Tovarnicka, Tereza; Sevcikova, Silvie; Kletecka, Jakub; Zatloukal, Jan; Pradl, Richard; Chytra, Ivan; Kasal, Eduard

    2015-02-01

    Intermittent blood pressure (BP) monitoring is the standard-of-care during low and intermediate risk anaesthesia, yet it could lead to delayed recognition of BP fluctuations. Perioperative hypotension is known to be associated with postoperative complications. Continuous, non-invasive methods for BP monitoring have been developed recently. We have tested a novel non-invasive, continuous monitor (using the volume clamp method) to assist with maintaining BP in safe ranges for patients undergoing surgery in a beach chair position. Forty adult patients undergoing thyroid gland surgery in an upright position were included in this prospective randomised controlled trial. Patients were equally allocated to the group with continuous monitoring of BP using the CNAP® Monitor and to the control group managed using an intermittent oscillometric BP cuff. The absolute and proportional time spent outside the range of ±20% of the target BP along with other hemodynamic and clinical parameters were evaluated. The continuous monitoring decreased the anaesthesia time spent below -20% pressure range [absolute: 12 min (4-20) vs. 27 min (16-34); p=0.001; relative to procedure length: 14% (7-20) vs. 33.5% (17.5-53); p=0.003]. No significant differences were observed in postoperative morbidity or in hospital length of stay. Continuous non-invasive BP monitoring via the CNAP® Monitor allows for better BP management in patients undergoing surgery in a beach chair position. In our randomised trial the time spent in hypotension was significantly shorter using continuous monitoring.

  3. The Book of Kells: A non-invasive MOLAB investigation by complementary spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Doherty, B.; Daveri, A.; Clementi, C.; Romani, A.; Bioletti, S.; Brunetti, B.; Sgamellotti, A.; Miliani, C.

    2013-11-01

    This paper highlights the efficacy of non-invasive portable spectroscopy for assessing the execution technique and constituent materials in one of the most important medieval manuscripts, the Book of Kells. An aimed campaign of in situ measurements by the MObile LABoratory (MOLAB) has analyzed its elemental composition and vibrational and electronic molecular properties. The ample analytical toolbox has afforded complementary diagnostic information of the pigment palette permitting the characterization of both inorganic and organic materials as pigments and dyes in the white, purple, blue, red, orange, green and black areas. In particular, the novel widespread use of calcinated gypsum (anhydrite) as both a white pigment and in correlation to the organic dyes in this manuscript has been noted. The non-invasive identification of the organic dye orchil is significant considering its rare non invasive detection in medieval manuscripts. Finally the occurrence of particular alterations of the organic black areas giving rise to calcium carboxylate and calcium oxalate has been specifically highlighted. Importantly, this work elaborates complex aspects of the employed painting materials which have given rise to numerous significant points of interest for a more elaborate understanding of this Irish treasure.

  4. Multi-scale simulations predict responses to non-invasive nerve root stimulation

    NASA Astrophysics Data System (ADS)

    Laakso, Ilkka; Matsumoto, Hideyuki; Hirata, Akimasa; Terao, Yasuo; Hanajima, Ritsuko; Ugawa, Yoshikazu

    2014-10-01

    Objective. Established biophysical neurone models have achieved limited success in reproducing electrophysiological responses to non-invasive stimulation of the human nervous system. This is related to our insufficient knowledge of the induced electric currents inside the human body. Despite the numerous research and clinical applications of non-invasive stimulation, it is still unclear which internal sites are actually affected by it. Approach. We performed multi-scale computer simulations that, by making use of advances in computing power and numerical algorithms, combine a microscopic model of electrical excitation of neurones with a macroscopic electromagnetic model of the realistic whole-body anatomy. Main results. The simulations yield responses consistent with those experimentally recorded following magnetic and electrical motor root stimulation in human subjects, and reproduce the observed amplitudes and latencies for a wide variety of stimulation parameters. Significance. Our findings demonstrate that modern computational techniques can produce detailed predictions about which and where neurones are activated, leading to improved understanding of the physics and basic mechanisms of non-invasive stimulation and enabling potential new applications that make use of improved targeting of stimulation.

  5. Non-invasive, transient determination of the core temperature of a heat-generating solid body

    NASA Astrophysics Data System (ADS)

    Anthony, Dean; Sarkar, Daipayan; Jain, Ankur

    2016-11-01

    While temperature on the surface of a heat-generating solid body can be easily measured using a variety of methods, very few techniques exist for non-invasively measuring the temperature inside the solid body as a function of time. Measurement of internal temperature is very desirable since measurement of just the surface temperature gives no indication of temperature inside the body, and system performance and safety is governed primarily by the highest temperature, encountered usually at the core of the body. This paper presents a technique to non-invasively determine the internal temperature based on the theoretical relationship between the core temperature and surface temperature distribution on the outside of a heat-generating solid body as functions of time. Experiments using infrared thermography of the outside surface of a thermal test cell in a variety of heating and cooling conditions demonstrate good agreement of the predicted core temperature as a function of time with actual core temperature measurement using an embedded thermocouple. This paper demonstrates a capability to thermally probe inside solid bodies in a non-invasive fashion. This directly benefits the accurate performance prediction and control of a variety of engineering systems where the time-varying core temperature plays a key role.

  6. Scanning superlens microscopy for non-invasive large field-of-view visible light nanoscale imaging

    NASA Astrophysics Data System (ADS)

    Wang, Feifei; Liu, Lianqing; Yu, Haibo; Wen, Yangdong; Yu, Peng; Liu, Zhu; Wang, Yuechao; Li, Wen Jung

    2016-12-01

    Nanoscale correlation of structural information acquisition with specific-molecule identification provides new insight for studying rare subcellular events. To achieve this correlation, scanning electron microscopy has been combined with super-resolution fluorescent microscopy, despite its destructivity when acquiring biological structure information. Here we propose time-efficient non-invasive microsphere-based scanning superlens microscopy that enables the large-area observation of live-cell morphology or sub-membrane structures with sub-diffraction-limited resolution and is demonstrated by observing biological and non-biological objects. This microscopy operates in both non-invasive and contact modes with ~200 times the acquisition efficiency of atomic force microscopy, which is achieved by replacing the point of an atomic force microscope tip with an imaging area of microspheres and stitching the areas recorded during scanning, enabling sub-diffraction-limited resolution. Our method marks a possible path to non-invasive cell imaging and simultaneous tracking of specific molecules with nanoscale resolution, facilitating the study of subcellular events over a total cell period.

  7. Hyperspectral imaging coupled with chemometric analysis for non-invasive differentiation of black pens

    NASA Astrophysics Data System (ADS)

    Chlebda, Damian K.; Majda, Alicja; Łojewski, Tomasz; Łojewska, Joanna

    2016-11-01

    Differentiation of the written text can be performed with a non-invasive and non-contact tool that connects conventional imaging methods with spectroscopy. Hyperspectral imaging (HSI) is a relatively new and rapid analytical technique that can be applied in forensic science disciplines. It allows an image of the sample to be acquired, with full spectral information within every pixel. For this paper, HSI and three statistical methods (hierarchical cluster analysis, principal component analysis, and spectral angle mapper) were used to distinguish between traces of modern black gel pen inks. Non-invasiveness and high efficiency are among the unquestionable advantages of ink differentiation using HSI. It is also less time-consuming than traditional methods such as chromatography. In this study, a set of 45 modern gel pen ink marks deposited on a paper sheet were registered. The spectral characteristics embodied in every pixel were extracted from an image and analysed using statistical methods, externally and directly on the hypercube. As a result, different black gel inks deposited on paper can be distinguished and classified into several groups, in a non-invasive manner.

  8. Non-invasive, transient determination of the core temperature of a heat-generating solid body.

    PubMed

    Anthony, Dean; Sarkar, Daipayan; Jain, Ankur

    2016-11-02

    While temperature on the surface of a heat-generating solid body can be easily measured using a variety of methods, very few techniques exist for non-invasively measuring the temperature inside the solid body as a function of time. Measurement of internal temperature is very desirable since measurement of just the surface temperature gives no indication of temperature inside the body, and system performance and safety is governed primarily by the highest temperature, encountered usually at the core of the body. This paper presents a technique to non-invasively determine the internal temperature based on the theoretical relationship between the core temperature and surface temperature distribution on the outside of a heat-generating solid body as functions of time. Experiments using infrared thermography of the outside surface of a thermal test cell in a variety of heating and cooling conditions demonstrate good agreement of the predicted core temperature as a function of time with actual core temperature measurement using an embedded thermocouple. This paper demonstrates a capability to thermally probe inside solid bodies in a non-invasive fashion. This directly benefits the accurate performance prediction and control of a variety of engineering systems where the time-varying core temperature plays a key role.

  9. Visual event-related potentials of dogs: a non-invasive electroencephalography study.

    PubMed

    Törnqvist, Heini; Kujala, Miiamaaria V; Somppi, Sanni; Hänninen, Laura; Pastell, Matti; Krause, Christina M; Kujala, Jan; Vainio, Outi

    2013-11-01

    Previously, social and cognitive abilities of dogs have been studied within behavioral experiments, but the neural processing underlying the cognitive events remains to be clarified. Here, we employed completely non-invasive scalp-electroencephalography in studying the neural correlates of the visual cognition of dogs. We measured visual event-related potentials (ERPs) of eight dogs while they observed images of dog and human faces presented on a computer screen. The dogs were trained to lie still with positive operant conditioning, and they were neither mechanically restrained nor sedated during the measurements. The ERPs corresponding to early visual processing of dogs were detectable at 75-100 ms from the stimulus onset in individual dogs, and the group-level data of the 8 dogs differed significantly from zero bilaterally at around 75 ms at the most posterior sensors. Additionally, we detected differences between the responses to human and dog faces in the posterior sensors at 75-100 ms and in the anterior sensors at 350-400 ms. To our knowledge, this is the first illustration of completely non-invasively measured visual brain responses both in individual dogs and within a group-level study, using ecologically valid visual stimuli. The results of the present study validate the feasibility of non-invasive ERP measurements in studies with dogs, and the study is expected to pave the way for further neurocognitive studies in dogs.

  10. Non-invasive saliva human biomonitoring: development of an in vitro platform.

    PubMed

    Weber, Thomas J; Smith, Jordan N; Carver, Zana A; Timchalk, Charles

    2017-01-01

    Direct measurements of exposure represent the most accurate assessment of a subject's true exposure. The clearance of many drugs and chemicals, including pesticides such as chlorpyrifos (CPF), can be detected non-invasively in saliva. Here we have developed a serous-acinar transwell model system as an in vitro screening platform to prioritize chemicals for non-invasive biomonitoring through salivary clearance mechanisms. Rat primary serous-acinar cells express both α-amylase and aquaporin-5 proteins and develop significant tight junctions at postconfluence - a feature necessary for chemical transport studies in vitro. CPF exhibited bidirectional passage across the serous-acinar barrier that was disproportional to the passage of a cell impermeable chemical (lucifer yellow), consistent with a hypothesized passive diffusion process. CPF was metabolized to trichlorpyridinol (TCPy) by serous-acinar cells, and TCPy also displayed bidirectional diffusion in the transwell assay. This model system should prove useful as an in vitro screening platform to support the non-invasive monitoring of toxicons and pharmacons in human saliva and provide guidance for development of advanced in vitro screening platforms utilizing primary human salivary gland epithelial cells.

  11. Prediction of oesophageal varices in patients with primary biliary cirrhosis by non-invasive markers

    PubMed Central

    Gao, Lili; Li, Hanwei; Han, Jun; Zhang, Weihui

    2017-01-01

    Introduction Preliminary data suggested that non-invasive methods could be useful to assess presence of oesophageal varices (OV) in liver cirrhosis. The primary objectives were to investigate non-invasive markers for diagnosing and grading OV in patients with primary biliary cirrhosis. Material and methods This study included a total of 106 consecutive treatment-naive patients with primary biliary cirrhosis (PBC). Results of physical examination, blood tests, and abdominal ultrasound scan (USS) were measured. Performance of non-invasive markers for OV was expressed as sensitivity, specificity, positive, and negative predictive values (PPV, NPV), accuracy, and area under the curve (AUC). Results Oesophageal varices were found in 54 (50.9%) and large OV in 28 of the 106 patients. Variables found to differ significantly between patients with any grade or large and without OV included increased spleen length, increased portal vein diameter, low platelet count, and low levels of albumin or low γ-glutamyltranspeptidase (γ-GTP) values. Area under the receiver operating characteristic curve showed that spleen length (cutoff = 156.0) had AUC 0.753 (95% CI: 0.657–0.849), and high NPV (82.1%) to exclude any grade OV. Large OV could be excluded with NPV 70.6% by spleen length. Conclusions Predictive risk factors that use readily available laboratory results and ultrasound scan results may reliably identify esophageal varices in patients with PBC. PMID:28261290

  12. Toenail as Non-invasive Biomarker in Metal Toxicity Measurement of Welding Fumes Exposure - A Review

    NASA Astrophysics Data System (ADS)

    Bakri, S. F. Z.; Hariri, A.; Ma'arop, N. F.; Hussin, N. S. A. W.

    2017-01-01

    Workers are exposed to a variety of heavy metal pollutants that are released into the environment as a consequence of workplace activities. This chemical pollutants are incorporated into the human by varies of routes entry and can then be stored and distributed in different tissues, consequently have a potential to lead an adverse health effects and/or diseases. As to minimize the impact, a control measures should be taken to avoid these effects and human biological marker is a very effective tool in the assessment of occupational exposure and potential related risk as the results is normally accurate and reproducible. Toenail is the ideal matrix for most common heavy metals due to its reliability and practicality compared to other biological samples as well as it is a non-invasive and this appears as a huge advantage of toenail as a biomarker. This paper reviews studies that measure the heavy metals concentration in toenail as non-invasive matrix which later may adapt in the investigation of metal fume emitted from welding process. The development of new methodology and modern analytical techniques has allowed the use of toenail as non-invasive approach. The presence of a heavy metal in this matrix reflects an exposure but the correlations between heavy metal levels in the toenail must be established to ensure that these levels are related to the total body burden. These findings suggest that further studies on interactions of these heavy metals in metal fumes utilizing toenail biomarker endpoints are highly warranted especially among welders.

  13. The Book of Kells: a non-invasive MOLAB investigation by complementary spectroscopic techniques.

    PubMed

    Doherty, B; Daveri, A; Clementi, C; Romani, A; Bioletti, S; Brunetti, B; Sgamellotti, A; Miliani, C

    2013-11-01

    This paper highlights the efficacy of non-invasive portable spectroscopy for assessing the execution technique and constituent materials in one of the most important medieval manuscripts, the Book of Kells. An aimed campaign of in situ measurements by the MObile LABoratory (MOLAB) has analyzed its elemental composition and vibrational and electronic molecular properties. The ample analytical toolbox has afforded complementary diagnostic information of the pigment palette permitting the characterization of both inorganic and organic materials as pigments and dyes in the white, purple, blue, red, orange, green and black areas. In particular, the novel widespread use of calcinated gypsum (anhydrite) as both a white pigment and in correlation to the organic dyes in this manuscript has been noted. The non-invasive identification of the organic dye orchil is significant considering its rare non invasive detection in medieval manuscripts. Finally the occurrence of particular alterations of the organic black areas giving rise to calcium carboxylate and calcium oxalate has been specifically highlighted. Importantly, this work elaborates complex aspects of the employed painting materials which have given rise to numerous significant points of interest for a more elaborate understanding of this Irish treasure.

  14. Non-drug Non-invasive Treatment in the Management of Low Back Pain

    PubMed Central

    Sahu, RL

    2014-01-01

    Background: Low back pain (LBP) is a major medical problem. World-wide, from 60% to 80% of people will have it during their lifetime and 2-5% will have it at any given time. The disease impacts upon activities of daily living ultimately leading to a loss of functional independence and quality of life. Aim: The main purpose of this study was to assess the results of non-drug non-invasive treatment in the management of LBP. Subjects and Methods: This was prospective study conducted in the Department of Orthopedics in M. M. Medical College, Mullana, Ambala, Haryana, India from June 2005 to June 2010. A total of 251 out-patients of LBP with a mean age of 45 years were studied. They were managed with non-invasive treatment and were followed for 24 months. Results: Objective Lumbar Spine Assessments up to the age of 40 years at 2 years were excellent. At 40-60 years of age, it was good to excellent. Over the age of 60 years, it was good. The back pain functional scale were found very good up to the age of 40 years at 2-year follow-up, good to very good between 40 and 60 years and over the age of 60 years it was good. Conclusions: Non-drug non-invasive interventions can reduce pain and improve function in LBP. PMID:25328793

  15. Preliminary results of a non-invasive method to measure tumor size and distribution in vivo

    PubMed Central

    Fu, Shu-Ling; Chen, Chien-An; Hung, Ling-Chien; Lee, Moon-Sing; Chiou, Wen-Yen; Lin, Hon-Yi; Su, Yu-Chieh; Lee, Ching-Chih; Hung, Shih-Kai

    2016-01-01

    Molecular imaging of reporter gene expression in cancer cells can provide rapid, sensitive and non-invasive monitoring of tumor behavior. The aim of the present study was to establish a non-invasive method to measure tumor size and distribution in vivo. Briefly, H-Ras-transformed cells were stably transfected with a plasmid containing the luciferase gene (Luc), designated as Ras/Luc. Ras/Luc cells were injected into the back or tail vein of nude BALB/cAnN-Foxn1nu/CrlNarl mice (age, 6–8 weeks). Mice were subsequently administered D-luciferin via intra-peritoneal injection, prior to image acquisition. Photons emitted from the mice were detected via an imaging system. Tumor size and distribution in vivo were quantified as photons/second. Andrographolide has demonstrated radiosensitization in previous in vitro and in vivo studies. In the present study, the potential effects of andrographolide cancer metastasis were investigated further, using an imaging system. Preliminary results of andrographolide combined with radiation indicated the inhibition of cancer metastasis. The present mechanistic study of andrographolide-mediated effects demonstrated that activated extracellular signal regulated kinase protein and H2O2 production levels were significantly increased by andrographolide. In summary, the present study established a non-invasive method to measure tumor size and distribution in vivo and indicated that andrographolide may be a potential therapeutic strategy in cancer therapy. PMID:28105095

  16. Retinal functional imager (RFI): non-invasive functional imaging of the retina.

    PubMed

    Ganekal, S

    2013-01-01

    Retinal functional imager (RFI) is a unique non-invasive functional imaging system with novel capabilities for visualizing the retina. The objective of this review was to show the utility of non-invasive functional imaging in various disorders. Electronic literature search was carried out using the websites www.pubmed.gov and www.google.com. The search words were retinal functional imager and non-invasive retinal imaging used in combination. The articles published or translated into English were studied. The RFI directly measures hemodynamic parameters such as retinal blood-flow velocity, oximetric state, metabolic responses to photic activation and generates capillary perfusion maps (CPM) that provides retinal vasculature detail similar to flourescein angiography. All of these parameters stand in a direct relationship to the function and therefore the health of the retina, and are known to be degraded in the course of retinal diseases. Detecting changes in retinal function aid early diagnosis and treatment as functional changes often precede structural changes in many retinal disorders.

  17. Oxidative stress in toadfish (Halobactrachus didactylus) cardiac muscle. Acute exposure to vanadate oligomers.

    PubMed

    Aureliano, M; Joaquim, N; Sousa, A; Martins, H; Coucelo, J M

    2002-06-07

    Vanadate solutions as "metavanadate" (containing ortho and metavanadate species) and "decavanadate" (containing mainly decameric species) (5 mM; 1 mg/kg) were injected intraperitoneously in Halobatrachus didactylus (toadfish), in order to evaluate the contribution of decameric vanadate species to vanadium (V) intoxication on the cardiac tissue. Following short-term exposure (1 and 7 days), different changes on antioxidant enzyme activities-superoxide dismutase (SOD), catalase (CAT), selenium-glutathione peroxidase (Se-GPx), total glutathione peroxidase (GPx), lipid peroxidation and subcellular vanadium distribution were observed in mitochondrial and cytosolic fractions of heart ventricle toadfish. After 1 day of vanadium intoxication, SOD, CAT and Se-GPx activities were decreased up to 25%, by both vanadate solutions, except mitochondrial CAT activity that increased (+23%) upon decavanadate administration. After 7 days of exposure, decavanadate versus metavanadate solutions promoted different effects mainly on cytosolic CAT activity (-56% versus -5%), mitochondrial CAT activity (-10% versus +10%) and total GPx activity (+1% versus -35%), whereas lipid peroxidation products were significantly increased (+82%) upon 500 microM decavanadate intoxication. Accumulation of vanadium in total (0.137+/-0.011 microg/g) and mitochondrial (0.022+/-0.001 microg/g) fractions was observed upon 7 days of metavanadate exposure, whereas for decavanadate, the concentration of vanadium increased in cytosolic (0.020+/-0.005 microg/g) and mitochondrial (0.021+/-0.009 microg/g) fractions. It is concluded that decameric vanadate species are responsible for a strong increase on lipid peroxidation and a decrease in cytosolic catalase activity thus contributing to oxidative stress responses upon vanadate intoxication, in the toadfish heart.

  18. Non-invasive submilligram level quantification of in vivo blood components with slitless high-sensitivity spectrometer and noncooled NIR detector

    NASA Astrophysics Data System (ADS)

    Kuribayashi, Ryosuke; Furukawa, Hiromitsu

    2015-03-01

    By using a "slit-less" Fourier-transform spectrometer, we demonstrate that cardiac-pulsation amplitude of absorbance can be extracted from 3.5-level absorbance unit (AU) spectra of a human fingertip with a resolution of < 0.0005 AU and a spectral resolution of < several tens of nanometers, even with a low-cost "non-cooled" NIR detector. From the extracted spectrum over 1,000-1,400 nm, the average amounts of pulsating blood components (water, HbO2, and lipids/proteins) in a fingertip are deduced in the sub-milligram order. The results indicate the capacity of the spectrometer for a portable non-invasive blood monitor as well as for a high-end analytic instrument.

  19. Keap1 redox-dependent regulation of doxorubicin-induced oxidative stress response in cardiac myoblasts

    SciTech Connect

    Nordgren, Kendra K.S. Wallace, Kendall B.

    2014-01-01

    Doxorubicin (DOX) is a widely prescribed treatment for a broad scope of cancers, but clinical utility is limited by the cumulative, dose-dependent cardiomyopathy that occurs with repeated administration. DOX-induced cardiotoxicity is associated with the production of reactive oxygen species (ROS) and oxidation of lipids, DNA and proteins. A major cellular defense mechanism against such oxidative stress is activation of the Keap1/Nrf2-antioxidant response element (ARE) signaling pathway, which transcriptionally regulates expression of antioxidant genes such as Nqo1 and Gstp1. In the present study, we address the hypothesis that an initial event associated with DOX-induced oxidative stress is activation of the Keap1/Nrf2-dependent expression of antioxidant genes and that this is regulated through drug-induced changes in redox status of the Keap1 protein. Incubation of H9c2 rat cardiac myoblasts with DOX resulted in a time- and dose-dependent decrease in non-protein sulfhydryl groups. Associated with this was a near 2-fold increase in Nrf2 protein content and enhanced transcription of several of the Nrf2-regulated down-stream genes, including Gstp1, Ugt1a1, and Nqo1; the expression of Nfe2l2 (Nrf2) itself was unaltered. Furthermore, both the redox status and the total amount of Keap1 protein were significantly decreased by DOX, with the loss of Keap1 being due to both inhibited gene expression and increased autophagic, but not proteasomal, degradation. These findings identify the Keap1/Nrf2 pathway as a potentially important initial response to acute DOX-induced oxidative injury, with the primary regulatory events being the oxidation and autophagic degradation of the redox sensor Keap1 protein. - Highlights: • DOX caused a ∼2-fold increase in Nrf2 protein content. • DOX enhanced transcription of several Nrf2-regulated down-stream genes. • Redox status and total amount of Keap1 protein were significantly decreased by DOX. • Loss of Keap1 protein was due to

  20. Non-invasive optical detection of glucose in cell culture nutrient medium

    NASA Technical Reports Server (NTRS)

    Cote, Gerald L.

    1993-01-01

    The objective of the proposed research was to begin the development of a non-invasive optical sensor for measuring glucose concentration in the output medium of cell cultures grown in a unique NASA bioreactor referred to as an integrated rotating-wall vessel (IRWV). The input, a bovine serum based nutrient media, has a known glucose concentration. The cells within the bioreactor digest a portion of the glucose. Thus, the non-invasive optical sensor is needed to monitor the decrease in glucose due to cellular consumption since the critical parameters for sustained cellular productivity are glucose and pH. Previous glucose sensing techniques have used chemical reactions to quantify the glucose concentration. Chemical reactions, however, cannot provide for continuous, real time, non-invasive measurement as is required in this application. Our effort while in the fellowship program was focused on the design, optical setup, and testing of one bench top prototype non-invasive optical sensor using a mid-infrared absorption spectroscopy technique. Glucose has a fundamental vibrational absorption peak in the mid-infrared wavelength range at 9.6 micron. Preliminary absorption data using a CO2 laser were collected at this wavelength for water based glucose solutions at different concentrations and one bovine serum based nutrient medium (GTSF) with added glucose. The results showed near linear absorption responses for the glucose-in-water data with resolutions as high at 108 mg/dl and as low as 10 mg/dl. The nutrient medium had a resolution of 291 mg/dl. The variability of the results was due mainly to thermal and polarization drifts of the laser while the decrease in sensitivity to glucose in the nutrient medium was expected due to the increase in the number of confounders present in the nutrient medium. A multispectral approach needs to be used to compensate for these confounders. The CO2 laser used for these studies was wavelength tunable (9.2 to 10.8 micrometers), however

  1. Association of neuropeptide Y promoter polymorphism (rs16147) with perceived stress and cardiac vagal outflow in humans

    PubMed Central

    Chang, Hsin-An; Fang, Wen-Hui; Chang, Tieh-Ching; Huang, San-Yuan; Chang, Chuan-Chia

    2016-01-01

    Neuropeptide Y (NPY) is involved in resilience to stress, and higher vagal (parasympathetic) activity has been associated with greater stress resilience. Thus, we examined whether rs16147, a functional promoter polymorphism (C>T) of the NPY gene, could influence vagal tone during chronic high stress levels. NPY genotyping, chronic psychological stress level measurement (using the Perceived Stress Scale [PSS]), cardiac autonomic function assessment (using short-term heart rate variability [HRV]) were performed in 1123 healthy, drug-free Han Chinese participants who were divided into low- and high-PSS groups. In the high-PSS group (n = 522), the root mean square of successive heartbeat interval differences and high frequency power (both HRV indices of parasympathetic activity) were significantly increased in T/T homozygotes compared to C/C homozygotes. However, no significant between-genotype difference was found in any HRV variable in the low-PSS group (n = 601). Our results are the first to demonstrate that functional NPY variation alters chronic stress-related vagal control, suggesting a potential parasympathetic role for NPY gene in stress regulation. PMID:27527739

  2. Algorithms based on CWT and classifiers to control cardiac alterations and stress using an ECG and a SCR.

    PubMed

    Villarejo, María Viqueira; Zapirain, Begoña García; Zorrilla, Amaia Méndez

    2013-05-10

    This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG) for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT) and J48) have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%), arrhythmia (93.48%) and extrasystoles (99.29%). The detection of stress level is complemented with Skin Conductance Response (SCR), whose success is 94.02%. The heart rate variability does not show added value to the stress detection in this case. With this pulsimeter, it is possible to prevent and detect anomalies for a non-intrusive way associated to a telemedicine system. It is also possible to use it during physical activity due to the fact the CWT minimizes the motion artifacts.

  3. Algorithms Based on CWT and Classifiers to Control Cardiac Alterations and Stress Using an ECG and a SCR

    PubMed Central

    Villarejo, María Viqueira; Zapirain, Begoña García; Zorrilla, Amaia Méndez

    2013-01-01

    This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG) for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT) and J48) have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%), arrhythmia (93.48%) and extrasystoles (99.29%). The detection of stress level is complemented with Skin Conductance Response (SCR), whose success is 94.02%. The heart rate variability does not show added value to the stress detection in this case. With this pulsimeter, it is possible to prevent and detect anomalies for a non-intrusive way associated to a telemedicine system. It is also possible to use it during physical activity due to the fact the CWT minimizes the motion artifacts. PMID:23666135

  4. Is a dietary n-3 fatty acid supplement able to influence the cardiac effect of the psychological stress?

    PubMed

    Rousseau, D; Moreau, D; Raederstorff, D; Sergiel, J P; Rupp, H; Muggli, R; Grynberg, A

    1998-01-01

    Epidemiological studies suggest that n-3 polyunsaturated fatty acids (PUFA) are involved in the prevention of cardiovascular disease. Stress is known to increase the incidence of CVD and the present study was realised to evaluate some physiological and biochemical effects of dietary docosahexaenoic acid (DHA) in male Wistar rats subjected to a psycho social stress. Rats were fed for 8 weeks a semi-purified diet containing 10% of either sunflower seed oil or the same oil supplemented with DHA. This food supply represented 50% of their daily requirement. The remaining 50% were supplied as 45 mg food pellets designed to induce stress in rats by an intermittent-feeding schedule process. The control group (n = 12) was fed the equivalent food ration as a single daily feeding. The physiological cardiovascular parameters were recorded by telemetry through a transmitter introduced in the abdomen. At the end of the experimentation, the heart and adrenals were withdrawn and the fatty acid composition and the catecholamine store were determined. Dietary DHA induced a pronounced alteration of the fatty acid profile of cardiac phospholipids (PL). The level of all the n-6 PUFAs was reduced while 22:6 n-3 was increased. The stress induced a significant increase in heart rate which was not observed in DHA-fed group. The time evolution of the systolic blood pressure was not affected by the stress and was roughly similar in the stressed rats of either dietary group. Conversely, the systolic blood pressure decreased in the unstressed rats fed DHA. Similar data were obtained for the diastolic blood pressure. The beneficial effect of DHA was also observed on cardiac contractility, since the dP/dt(max) increase was prevented in the DHA-fed rats. The stress-induced modifications were associated with an increase in cardiac noradrenaline level which was not observed in DHA-fed rats. The fatty acid composition of adrenals was significantly related to the fatty acid intake particularly the

  5. Effect of rosuvastatin on obesity-induced cardiac oxidative stress in Wistar rats--a preliminary study.

    PubMed

    Ansari, Javed A; Bhandari, Uma; Pillai, K K; Haque, S E

    2012-03-01

    The prevalence of obesity has been rising alarmingly and it has now become a global concern causing an enormous economic burden on the health care system. Obesity is generally linked to complications in lipid metabolism and oxidative stress. The aim of the present study was to investigate the effect of rosuvastatin (10 mg/kg, po) on obesity-induced oxidative stress in high fat-fed Wistar rats. Oral administration of rosuvastatin (10 mg/kg) for 21 days along with high fat diet brought about significant elevation in serum high density lipoprotein and cardiac antioxidant enzymes levels (superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione peroxidase-, glutathione reductase- and glutathione-S-transferase) while decreasing in serum lactate dehydrogenase, apolipoprotein-B, lipids (triglycerides, total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and atherogenic index) and cardiac thiobarbituric acid reactive substances levels. The results were comparable with orlistat, a standard antiobesity drug. These preliminary results for the first time demonstrate that administration of rosuvastatin can be beneficial for the suppression of obesity-induced oxidative stress and dyslipidemia in high fat-fed Wistar rats.

  6. Effects of psychological stress test on the cardiac response of public safety workers: alternative parameters to autonomic balance

    NASA Astrophysics Data System (ADS)

    Huerta-Franco, M. R.; Vargas-Luna, F. M.; Delgadillo-Holtfort, I.

    2015-01-01

    It is well known that public safety workers (PSW) face many stressful situations that yield them as high-risk population for suffering chronic stress diseases. In this multidisciplinary research the cardiac response to induced psychological stress by a short duration Stroop test was evaluated in 20 female and 19 male PSW, in order to compare traditionally used cardiac response parameters with alternative ones. Electrocardiograms have been recorded using the Eindhoven electrodes configuration for 1 min before, 3 min during and 1 min after the test. Signals analysis has been performed for the heart rate and the power spectra of its variability and of the variability of the amplitude of the R-wave, i.e. the highest peak of the electrocardiographic signal periodic sequence. The results demonstrated that the traditional autonomic balance index shows no significant differences between stages. In contrast, the median of the area of the power spectrum of the R-wave amplitude variability in the frequency region dominated by the autonomous nervous system (0.04-to-0.4 Hz) is the more sensitive parameter. Moreover, this parameter allows to identify gender differences consistent with those encountered in other studies.

  7. Frequency of stress lesions of the upper gastrointestinal tract in paediatric patients after cardiac surgery: effects of prophylaxis.

    PubMed Central

    Behrens, R; Hofbeck, M; Singer, H; Scharf, J; Rupprecht, T

    1994-01-01

    BACKGROUND--Stress lesions of the upper gastrointestinal tract are well recognised in adult patients in intensive care. There are no controlled studies of the incidence of these lesions and the effects or side effects of prophylactic treatment in high risk paediatric patients. METHODS--79 paediatric patients in intensive care were studied prospectively after operation for congenital heart disease. All patients had at least one endoscopic examination. The first 36 patients were not given prophylactic medication: later 43 children were treated randomly either with pirenzepine (n = 21) or with famotidine (n = 22). Gastric and tracheal secretions were taken daily for culture in those patients given prophylactic medication. RESULTS--Severe inflammation or ulceration of the upper gastrointestinal tract was less common in those patients who were given prophylactic medication (18% v 44%). Prophylactic treatment did not, however, reduce the total incidence of postoperative stress lesions: it shifted the severity of these changes towards mild lesions and reduced the incidence of ulcerations from 25% to 2%. None of the patients developed a pneumonia caused by an organism previously isolated from the stomach. CONCLUSIONS--The incidence of stress lesions in children after cardiac surgery resembles that in high risk adult patients. Children in intensive care after cardiac surgery should be treated prophylactically with famotidine or pirenzepine until they can be fed by mouth. PMID:7917695

  8. Non-invasive Investigations for the Diagnosis of Fontan-Associated Liver Disease in Pediatric and Adult Fontan Patients

    PubMed Central

    Fidai, Amyna; Dallaire, Frederic; Alvarez, Nanette; Balon, Yvonne; Clegg, Robin; Connelly, Michael; Dicke, Frank; Fruitman, Deborah; Harder, Joyce; Myers, Kimberley; Patton, David J.; Prieur, Tim; Vorhies, Erika; Myers, Robert P.; Martin, Steven R.; Greenway, Steven C.

    2017-01-01

    Fontan-associated liver disease (FALD) is a serious complication related to the chronically elevated venous pressure and low cardiac output of this abnormal circulation. However, diagnostic markers for this condition are limited. We hypothesized that specific tests for fibrosis developed for other chronic liver diseases would identify a higher prevalence of FALD than ultrasound and standard laboratory tests and that identified abnormalities would correlate with time post-Fontan. In this cross-sectional study, we assessed 19 children (average age 8.4 ± 4.3 and 5.4 ± 4.1 years post-Fontan) and 8 adults (average age 31.5 ± 8.9 and 21.1 ± 4 years post-Fontan) using standard serum laboratory investigations assessing hepatic integrity and function, the FibroTest, liver ultrasound, and transient elastography (FibroScan). In adult Fontan patients, hemoglobin, C-reactive protein, and gamma-glutamyl transpeptidase were significantly increased, and white blood cell and platelet counts were significantly decreased in comparison to the pediatric cohort. International normalized ratio was mildly elevated in both children and adults. FibroTest results were suggestive of fibrosis regardless of time post-Fontan. FibroScan measurements were significantly correlated with time post-Fontan, but the incidence of ultrasound-detected liver abnormalities was variable. No cases of hepatocellular carcinoma were identified. Abnormalities suggestive of FALD occur in both children and adults post-Fontan. Select laboratory tests, and possibly ultrasound and FibroScan in some patients, appear to have the most promise for the non-invasive detection of FALD.

  9. Pulse oximetry in the pulmonary tissue for the non-invasive measurement of mixed venous oxygen saturation.

    PubMed

    Nitzan, Meir; Nitzan, Itamar

    2013-08-01

    The oxygen saturation of the systemic arterial blood is associated with the adequacy of respiration, and can be measured non-invasively by pulse oximetry in the systemic tissue. The oxygen saturation of the blood in the pulmonary artery, the mixed venous blood, reflects the balance between oxygen supply to the systemic tissues and their oxygen demand. The mixed venous oxygen saturation has also clinical significance because it is used in Fick equation for the quantitative measurement of cardiac output. At present the measurement of the mixed venous oxygen saturation is invasive and requires insertion of a Swan-Ganz catheter into the pulmonary artery. We suggest a noninvasive method for the measurement of the mixed venous oxygen saturation in infants, pulmonary pulse oximetry. The method is similar to the systemic pulse oximetry, which is based on the different light absorption curves of oxygenated and deoxygenated hemoglobin and on the analysis of photoplethysmographic curves in two wavelengths. The proposed pulmonary pulse oximeter includes light-sources of two wavelengths in the infrared, which illuminate the pulmonary tissue through the thoracic wall. Part of the light which is scattered back from the pulmonary tissue and passes through the thoracic wall is detected, and for each wavelength a pulmonary photoplethysmographic curve is obtained. The pulmonary photoplethysmographic curves reflect blood volume increase during systole in the pulmonary arteries in the lung tissue, which contain mixed venous blood. The ratio R of the amplitude-to-baseline ratio for the two wavelengths is related to the mixed venous oxygen saturation through equations derived for the systemic pulse oximetry. The method requires the use of extinction coefficients values for oxygenated and deoxygenated hemoglobin, which can be found in the literature.

  10. Non invasive Measurements of Myocardial Hypertrophy in Patients with Essential Hypertension Treated with Eprosartan: Contribution of the Physics

    SciTech Connect

    Cabrera Sole, Ricardo

    2007-04-28

    Objective: The main objective of this study was to evaluate the effects of the treatment with eprosartan on cardiac hypertrophy in hypertensive patients using the echocardiogram to measure the hypertrophy of left ventricle. We studied 60 untreated patients diagnosed of mild to moderate hypertension which received after the diagnosis 600 mg/day of eprosartan, a novel direct angiotensin inhibitor recently introduced to treat hypertension. All patients were submitted to a standard echocardiographic study before the treatment and after 6 months of it We evaluated by echocardiogram the following parameters: left ventricular septum and posterior wall thickness, left ventricular mass, E/A index of mitral flow considering abnormal when this index was less than 1, and left ventricular ejection fraction. Results: at the beginning we found a systolic/diastolic pressures of 165{+-}9/ 96{+-}4 mmHg compared with the end of study of 124{+-}2/79{+-}3 mmHg (p<0.05). Septum and posterior wall thickness were respectively at baseline 13.2{+-}2 and 12.1{+-}1.1 mmHg and at the end 11.5{+-}1.2 and 10.5{+-}1.3 mmHg (p<0.05 for both of them). The E/A mitral flow index was less than 1 at baseline in 45 patients compared with 19 patients after treatment (p<0.05). Respect to left ventricular mass we found at the beginning 232{+-}7.5 gr., compared to 194{+-}9 gr., at the end of this study (p<0.05). We did not find any significant differences regarding left ventricular ejection fraction between both groups. Conclusions: we can remark that eprosartan is a very useful drug to reduce not only blood pressure but also left ventricular hypertrophy and improve left ventricular diastolic function in patients with essential hypertension according with parameters measured with non invasive methods.

  11. Non invasive Measurements of Myocardial Hypertrophy in Patients with Essential Hypertension Treated with Eprosartan: Contribution of the Physics

    NASA Astrophysics Data System (ADS)

    Cabrera Solé, Ricardo

    2007-04-01

    Objective: The main objective of this study was to evaluate the effects of the treatment with eprosartan on cardiac hypertrophy in hypertensive patients using the echocardiogram to measure the hypertrophy of left ventricle. We studied 60 untreated patients diagnosed of mild to moderate hypertension which received after the diagnosis 600 mg/day of eprosartan, a novel direct angiotensin inhibitor recently introduced to treat hypertension. All patients were submitted to a standard echocardiographic study before the treatment and after 6 months of it We evaluated by echocardiogram the following parameters: left ventricular septum and posterior wall thickness, left ventricular mass, E/A index of mitral flow considering abnormal when this index was less than 1, and left ventricular ejection fraction. Results: at the beginning we found a systolic/diastolic pressures of 165±9/ 96±4 mmHg compared with the end of study of 124±2/79±3 mmHg (p<0.05). Septum and posterior wall thickness were respectively at baseline 13.2±2 and 12.1±1.1 mmHg and at the end 11.5±1.2 and 10.5±1.3 mmHg (p<0.05 for both of them). The E/A mitral flow index was less than 1 at baseline in 45 patients compared with 19 patients after treatment (p<0.05). Respect to left ventricular mass we found at the beginning 232±7.5 gr., compared to 194±9 gr., at the end of this study (p<0.05). We did not find any significant differences regarding left ventricular ejection fraction between both groups. Conclusions: we can remark that eprosartan is a very useful drug to reduce not only blood pressure but also left ventricular hypertrophy and improve left ventricular diastolic function in patients with essential hypertension according with parameters measured with non invasive methods.

  12. Fatigue life estimation procedures for the endurance of a cardiac valve prosthesis: stress/life and damage-tolerant analyses.

    PubMed

    Ritchie, R O; Lubock, P

    1986-05-01

    Projected fatigue life analyses are performed to estimate the endurance of a cardiac valve prosthesis under physiological environmental and mechanical conditions. The analyses are conducted using both the classical stress-strain/life and the fracture mechanics-based damage-tolerant approaches, and provide estimates of expected life in terms of initial flaw sizes which may pre-exist in the metal prior to the valve entering service. The damage-tolerant analysis further is supplemented by consideration of the question of "short cracks," which represents a developing area in metal fatigue research, not commonly applied to data in standard engineering design practice.

  13. Non-Invasive Detection of CH-46 AFT Gearbox Faults Using Digital Pattern Recognition and Classification Techniques

    DTIC Science & Technology

    2007-11-02

    A TRIDENT SCHOLAR PROJECT REPORT NO. 266 NON-INVASIVE DETECTION OF CH-46 AFT GEARBOX FAULTS USING DIGITAL PATTERN RECOGNITION AND CLASSIFICATION...NUMBERS Non-invasive detection of CH-46 AFT gearbox faults using digital pattern recognition and classification techniques 6. AUTHOR(S) Rex, Bryan D...helicopter gearboxes in order to d~iagnose end correct possible fault condi.itons (incipient faults ) which could eventually lead to gearbox failure. This

  14. The use of infrared thermography as a non-invasive method for fever detection in sheep infected with bluetongue virus.

    PubMed

    Pérez de Diego, Ana C; Sánchez-Cordón, Pedro J; Pedrera, Miriam; Martínez-López, Beatriz; Gómez-Villamandos, José C; Sánchez-Vizcaíno, José M

    2013-10-01

    Fever, which is closely linked to viraemia, is considered to be both the main and the earliest clinical sign in sheep infected with bluetongue virus (BTV). The aim of this study was to evaluate the potential use of infrared thermography (IRT) for early detection of fever in sheep experimentally infected with bluetongue virus serotype 1 (BTV-1) and serotype 8 (BTV-8). This would reduce animal stress during experimental assays and assist in the development of a screening method for the identification of fever in animals suspected of being infected with BTV. Rectal and infrared eye temperatures were collected before and after BTV inoculation. The two temperature measures were positively correlated (r=0.504, P<0.05). The highest correlation between rectal and infrared temperatures was observed when temperatures were above physiological levels. IRT discriminated between febrile and non-febrile sheep with a sensitivity of 85% and specificity of 97%. The results showed that eye temperature measured using IRT was a useful non-invasive method for the assessment of fever in sheep infected with BTV under experimental conditions. Further research is required to evaluate the use of IRT under field conditions to identify potentially infected animals in bluetongue surveillance programmes.

  15. Immobilization Stress With α2-Adrenergic Stimulation Induces Regional and Transient Reduction of Cardiac Contraction Through Gi Coupling in Rats.

    PubMed

    Kuroda, Ryohei; Shintani-Ishida, Kaori; Unuma, Kana; Yoshida, Ken-ichi

    2015-01-01

    Stress cardiomyopathy is characterized by transient apical hypokinesia related to catecholamine overflow. Recently, excessive epinephrine administration was shown to recapitulate stress cardiomyopathy through β2-adrenoceptor (AR)-inhibitory G protein (Gi) coupling in rats. We aimed to study whether α2-AR and Gi affect cardiac contraction in rats in which emotional stress was evoked using immobilization (IMO). Echocardiography results showed that when male rats were exposed to IMO for 30 minutes and then injected with the α2-AR agonist xylazine (Xy), ejection fraction and the movement of the anterior wall (AW) were suppressed, maximally at 5 minutes post-injection, whereas posterior wall (PW) movement was preserved. At the same time points, the phosphorylation of Ser282 in myosin-binding protein-C (MyBP-C-Ser282) was higher in the PW than in the AW. Pretreatment with the Gi inhibitor pertussis toxin (PTX) reversed the low contractility and MyBP-C-Ser282 phosphorylation in the AW, but induced lethal heart failure in 3 out of 11 rats. Moreover, at 5 minutes after Xy injection following 30 minutes of IMO, serum epinephrine levels were increased. Thus, in rats exposed to psychological stress, α2-AR stimulation triggered transient hypo-contractility and MyBP-C-Ser282 hypo-phosphorylation in the AW, in association with an epinephrine surge. PTX treatment reversed the AW hypo-contractility and MyBP-C hypo-phosphorylation, but induced acute heart failure. These findings suggest α2AR/Gi-dependent signaling attenuates MyBP-C phosphorylation and contractility in the AW through an epinephrine surge in rats subjected to IMO and α2-AR stimulation. This model can recapitulate stress cardiomyopathy and thereby deepen our understanding of regional cardiac hypo-contractility and prosurvival mechanisms.

  16. Ambulatory and Challenge-Associated Heart Rate Variability Measures Predict Cardiac Responses to “Real-World” Acute Emotional Stress

    PubMed Central

    Dikecligil, GN; Mujica-Parodi, LR

    2010-01-01

    Background Heart rate variability (HRV) measures homeostatic regulation of the autonomic nervous system in response to perturbation, and has been previously shown to quantify risk for cardiac events. In spite of known interactions between stress vulnerability, psychiatric illness, and cardiac health, however, to our knowledge this is the first study to directly compare the value of laboratory HRV in predicting autonomic modulation of “real-world” emotional stress. Methods We recorded ECG on 56 subjects: first, within the laboratory, and then during an acute emotional stressor: a first-time skydive. Laboratory sessions included two five-minute ECG recordings separated by one ambulatory 24-hour recording. To test the efficacy of introducing a mild emotional challenge, during each of the five-minute laboratory recordings subjects viewed either aversive or benign images. Following the laboratory session, subjects participated in the acute stressor wearing a holter ECG. Artifact-free ECGs (N=33) were analyzed for HRV, then statistically compared across laboratory and acute stress sessions. Results There were robust correlations (r=0.7-0.8) between the laboratory and acute stress HRV, indicating that the two most useful paradigms (long-term wake, followed by short-term challenge) also were most sensitive to distinct components of the acute stressor: the former correlated with the fine-tuned regulatory modulation occurring immediately prior and following the acute stressor, while the latter correlated with gross amplitude and recovery. Conclusions Our results confirmed the efficacy of laboratory-acquired HRV in predicting autonomic response to acute emotional stress, and suggest that ambulatory and challenge protocols enhance predictive value. PMID:20299007

  17. Non-Invasive Prenatal Diagnosis of Lethal Skeletal Dysplasia by Targeted Capture Sequencing of Maternal Plasma

    PubMed Central

    Wang, Yaoshen; Chen, Chao; Gao, Changxin; Yu, Song; Liu, Yan; Song, Wei; Asan; Zhu, Hongmei; Yang, Ling; Deng, Hongmei; Su, Yue; Yi, Xin

    2016-01-01

    Background Since the discovery of cell-free foetal DNA in the plasma of pregnant women, many non-invasive prenatal testing assays have been developed. In the area of skeletal dysplasia diagnosis, some PCR-based non-invasive prenatal testing assays have been developed to facilitate the ultrasound diagnosis of skeletal dysplasias that are caused by de novo mutations. However, skeletal dysplasias are a group of heterogeneous genetic diseases, the PCR-based method is hard to detect multiple gene or loci simultaneously, and the diagnosis rate is highly dependent on the accuracy of the ultrasound diagnosis. In this study, we investigated the feasibility of using targeted capture sequencing to detect foetal de novo pathogenic mutations responsible for skeletal dysplasia. Methodology/Principal Findings Three families whose foetuses were affected by skeletal dysplasia and two control families whose foetuses were affected by other single gene diseases were included in this study. Sixteen genes related to some common lethal skeletal dysplasias were selected for analysis, and probes were designed to capture the coding regions of these genes. Targeted capture sequencing was performed on the maternal plasma DNA, the maternal genomic DNA, and the paternal genomic DNA. The de novo pathogenic variants in the plasma DNA data were identified using a bioinformatical process developed for low frequency mutation detection and a strict variant interpretation strategy. The causal variants could be specifically identified in the plasma, and the results were identical to those obtained by sequencing amniotic fluid samples. Furthermore, a mean of 97% foetal specific alleles, which are alleles that are not shared by maternal genomic DNA and amniotic fluid DNA, were identified successfully in plasma samples. Conclusions/Significance Our study shows that capture sequencing of maternal plasma DNA can be used to non-invasive detection of de novo pathogenic variants. This method has the potential

  18. Non-Invasive Assessment of Skeletal Muscle Myosin Heavy Chain Expression in Trained and Untrained Men.

    PubMed

    Fry, Andrew C; Housh, Terry J; Cramer, Joel B; Weir, Joseph P; Beck, Travis W; Schilling, Brian K; Miller, Jonathan D; Nicoll, Justin X

    2016-09-20

    Numerous conditions and types of physical activity (e.g., exercise, aging, muscle-related diseases) can influence muscle fiber types and the proteins expressed. To date, muscle fibers can only be characterized by actually obtaining a tissue sample using the invasive muscle biopsy procedure. Mechanomyography (MMG) is the assessment of the vibration properties of contracting skeletal muscle, and has been proposed as a possible non-invasive method for muscle fiber analysis. Therefore, the purpose of this project was to examine the feasibility of using MMG and muscle performance measures to non-invasively assess muscle fiber characteristics. Fifteen men (5 endurance-trained [End], 5 weight-trained [WT], and 5 sedentary [Sed]) provided muscle samples from their vastus lateralis muscle. These samples were analyzed for relative myosin heavy chain protein expression, which is highly correlated with % muscle fiber type areas. Additionally, each subject performed several muscle performance tests, and MMG of the quadriceps was assessed during a knee extension exercise. Multiple regression was used to develop prediction equations for determining relative muscle content of myosin heavy chain (MHC) types I, IIa, and IIx. A combination of MMG and knee extension performance variables estimated types I, IIa, and IIx MHC with approximately 80% accuracy. Although preliminary, these data suggest that muscle performance tests in addition to MMG assessments during a simple muscle performance task (knee extension) can be used to estimate muscle fiber type composition in a healthy male population. Such methods could ultimately be used to non-invasively monitor muscle health and fitness.

  19. Highly sensitive, non-invasive detection of colorectal cancer mutations using single molecule, third generation sequencing

    PubMed Central

    Russo, Giancarlo; Patrignani, Andrea; Poveda, Lucy; Hoehn, Frederic; Scholtka, Bettina; Schlapbach, Ralph; Garvin, Alex M.

    2015-01-01

    Colorectal cancer (CRC) represents one of the most prevalent and lethal malignant neoplasms and every individual of age 50 and above should undergo regular CRC screening. Currently, the most effective preventive screening procedure to detect adenomatous polyps, the precursors to CRC, is colonoscopy. Since every colorectal cancer starts as a polyp, detecting all polyps and removing them is crucial. By exactly doing that, colonoscopy reduces CRC incidence by 80%, however it is an invasive procedure that might have unpleasant and, in rare occasions, dangerous side effects. Despite numerous efforts over the past two decades, a non-invasive screening method for the general population with detection rates for adenomas and CRC similar to that of colonoscopy has not yet been established. Recent advances in next generation sequencing technologies have yet to be successfully applied to this problem, because the detection of rare mutations has been hindered by the systematic biases due to sequencing context and the base calling quality of NGS. We present the first study that applies the high read accuracy and depth of single molecule, real time, circular consensus sequencing (SMRT-CCS) to the detection of mutations in stool DNA in order to provide a non-invasive, sensitive and accurate test for CRC. In stool DNA isolated from patients diagnosed with adenocarcinoma, we are able to detect mutations at frequencies below 0.5% with no false positives. This approach establishes a foundation for a non-invasive, highly sensitive assay to screen the population for CRC and the early stage adenomas that lead to CRC. PMID:27054083

  20. Highly sensitive, non-invasive detection of colorectal cancer mutations using single molecule, third generation sequencing.

    PubMed

    Russo, Giancarlo; Patrignani, Andrea; Poveda, Lucy; Hoehn, Frederic; Scholtka, Bettina; Schlapbach, Ralph; Garvin, Alex M

    2015-12-01

    Colorectal cancer (CRC) represents one of the most prevalent and lethal malignant neoplasms and every individual of age 50 and above should undergo regular CRC screening. Currently, the most effective preventive screening procedure to detect adenomatous polyps, the precursors to CRC, is colonoscopy. Since every colorectal cancer starts as a polyp, detecting all polyps and removing them is crucial. By exactly doing that, colonoscopy reduces CRC incidence by 80%, however it is an invasive procedure that might have unpleasant and, in rare occasions, dangerous side effects. Despite numerous efforts over the past two decades, a non-invasive screening method for the general population with detection rates for adenomas and CRC similar to that of colonoscopy has not yet been established. Recent advances in next generation sequencing technologies have yet to be successfully applied to this problem, because the detection of rare mutations has been hindered by the systematic biases due to sequencing context and the base calling quality of NGS. We present the first study that applies the high read accuracy and depth of single molecule, real time, circular consensus sequencing (SMRT-CCS) to the detection of mutations in stool DNA in order to provide a non-invasive, sensitive and accurate test for CRC. In stool DNA isolated from patients diagnosed with adenocarcinoma, we are able to detect mutations at frequencies below 0.5% with no false positives. This approach establishes a foundation for a non-invasive, highly sensitive assay to screen the population for CRC and the early stage adenomas that lead to CRC.

  1. Challenges on non-invasive ventilation to treat acute respiratory failure in the elderly.

    PubMed

    Scala, Raffaele

    2016-11-15

    Acute respiratory failure is a frequent complication in elderly patients especially if suffering from chronic cardio-pulmonary diseases. Non-invasive mechanical ventilation constitutes a successful therapeutic tool in the elderly as, like in younger patients, it is able to prevent endotracheal intubation in a wide range of acute conditions; moreover, this ventilator technique is largely applied in the elderly in whom invasive mechanical ventilation is considered not appropriated. Furthermore, the integration of new technological devices, ethical issues and environment of treatment are still largely debated in the treatment of acute respiratory failure in the elderly.This review aims at reporting and critically analyzing the peculiarities in the management of acute respiratory failure in elderly people, the role of noninvasive mechanical ventilation, the potential advantages of applying alternative or integrated therapeutic tools (i.e. high-flow nasal cannula oxygen therapy, non-invasive and invasive cough assist devices and low-flow carbon-dioxide extracorporeal systems), drawbacks in physician's communication and "end of life" decisions. As several areas of this topic are not supported by evidence-based data, this report takes in account also "real-life" data as well as author's experience.The choice of the setting and of the timing of non-invasive mechanical ventilation in elderly people with advanced cardiopulmonary disease should be carefully evaluated together with the chance of using integrated or alternative supportive devices. Last but not least, economic and ethical issues may often challenges the behavior of the physicians towards elderly people who are hospitalized for acute respiratory failure at the end stage of their cardiopulmonary and neoplastic diseases.

  2. A REVIEW OF NON-INVASIVE IMAGING METHODS AND APPLICATIONS IN CONTAMINANT HYDROGEOLOGY RESEARCH

    SciTech Connect

    Werth, Charles J.; Zhang, Changyong; Brusseau, M. L.; Oostrom, Martinus; Baumann, T.

    2010-03-08

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. The most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma-radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods’ advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  3. A review of non-invasive imaging methods and applications in contaminant hydrogeology research.

    PubMed

    Werth, Charles J; Zhang, Changyong; Brusseau, Mark L; Oostrom, Mart; Baumann, Thomas

    2010-04-01

    Contaminant hydrogeological processes occurring in porous media are typically not amenable to direct observation. As a result, indirect measurements (e.g., contaminant breakthrough at a fixed location) are often used to infer processes occurring at different scales, locations, or times. To overcome this limitation, non-invasive imaging methods are increasingly being used in contaminant hydrogeology research. Four of the most common methods, and the subjects of this review, are optical imaging using UV or visible light, dual-energy gamma radiation, X-ray microtomography, and magnetic resonance imaging (MRI). Non-invasive imaging techniques have provided valuable insights into a variety of complex systems and processes, including porous media characterization, multiphase fluid distribution, fluid flow, solute transport and mixing, colloidal transport and deposition, and reactions. In this paper we review the theory underlying these methods, applications of these methods to contaminant hydrogeology research, and methods' advantages and disadvantages. As expected, there is no perfect method or tool for non-invasive imaging. However, optical methods generally present the least expensive and easiest options for imaging fluid distribution, solute and fluid flow, colloid transport, and reactions in artificial two-dimensional (2D) porous media. Gamma radiation methods present the best opportunity for characterization of fluid distributions in 2D at the Darcy scale. X-ray methods present the highest resolution and flexibility for three-dimensional (3D) natural porous media characterization, and 3D characterization of fluid distributions in natural porous media. And MRI presents the best option for 3D characterization of fluid distribution, fluid flow, colloid transport, and reaction in artificial porous media. Obvious deficiencies ripe for method development are the ability to image transient processes such as fluid flow and colloid transport in natural porous media in three

  4. Comparison of Non-Invasive Methods for the Detection of Coronary Atherosclerosis

    PubMed Central

    Bampi, Angela Bacelar Albuquerque; Rochitte, Carlos Eduardo; Favarato, Desiderio; Lemos, Pedro Alves; da Luz, Protásio Lemos

    2009-01-01

    BACKGROUND: Non-invasive detection of atherosclerosis is critical for its prevention. Objective: To correlate non-invasively detectable indicators of coronary atherosclerosis, or Coronary Artery Disease (i.e., classical risk factors, hs-CRP test results, carotid intima-media thickness, endothelial function, ankle-brachial index and calcium score by computed tomography) with the extent of coronary disease assessed by the Friesinger index from conventional coronary angiography. METHODS: We conducted a prospective study of 100 consecutive patients, mean age 55.1 ± 10.7 years, 55% men and 45% women. Patients with acute coronary syndrome, renal dialytic insufficiency, collagen disease and cancer were not included. All patients were subjected to clinical evaluation and laboratory tests. Endothelial function of the brachial artery and carotid artery were evaluated by high-resolution ultrasound; ankle-brachial index and computed tomography for coronary determination of calcium score were also performed, and non-HDL cholesterol and TG/HDL-c ratio were calculated. All patients were subjected to coronary angiography at the request of the assistant physician. We considered patients without an obstructive lesion (< 29% stenosis) demonstrated by coronary angiography to be normal. RESULTS: Univariate analysis showed that calcium score, HDL-c, TG/HDL ratio and IMT were significantly correlated with the Friesinger index. However, multivariate analysis indicated that only calcium score and low HDL-c levels correlated significantly with the extension of CAD. On the other hand, hs-CRP, LDL-c, flow-mediated dilation, and Framingham score did not correlate with the Friesinger index. ROC analysis showed that calcium score, HDL-c and TG-HDL ratio accurately predicted extensive CAD in a statistically significant manner. CONCLUSION: It is possible to approximately determine the presence and extent of CAD by non-invasive methods, especially by calcium score, HDL-c and TG/HDL-c ratio assays

  5. The immunological response created by interstitial and non-invasive laser immunotherapy

    NASA Astrophysics Data System (ADS)

    Bahavar, Cody F.; Zhou, Feifan; Hasanjee, Aamr M.; West, Connor L.; Nordquist, Robert E.; Hode, Tomas; Liu, Hong; Chen, Wei R.

    2015-03-01

    Laser immunotherapy (LIT) is an innovative cancer modality that uses laser irradiation and immunological stimulation to treat late-stage, metastatic cancers. LIT can be performed through either interstitial or non-invasive laser irradiation. Although LIT is still in development, recent clinical trials have shown that it can be used to successfully treat patients with late-stage breast cancer and melanoma. The development of LIT has been focused on creating an optimal immune response created by irradiating the tumor. One important factor that could enhance the immune response is the duration of laser irradiation. Irradiating the tumor for a shorter or longer amount of time could weaken the immune response created by LIT. Another factor that could weaken this immune response is the proliferation of regulatory T cells (TRegs) in response to the laser irradiation. However, low dose cyclophosphamide (CY) can help suppress the proliferation of TRegs and help create a more optimal immune response. An additional factor that could weaken the effectiveness of LIT is the selectivity of the laser. If LIT is performed non-invasively, then deeply embedded tumors and highly pigmented skin could cause an uneven temperature distribution inside the tumor. To solve this problem, an immunologically modified carbon nanotube system was created by using an immunoadjuvant known as glycated chitosan (GC) as a surfactant for single-walled carbon nanotubes (SWNTs) to immunologically modify SWNTs. SWNT-GC retains the optical properties of SWNTs and the immunological functions of GC to help increase the selectivity of the laser and create a more optimal immune response. In this preliminary study, tumor-bearing rats were treated with LIT either interstitially by an 805-nm laser with GC and low-dose CY, or non-invasively by a 980-nm laser with SWNT-GC. The goal was to observe the effects of CY on the immune response induced by LIT and to also determine the effect of irradiation duration for

  6. Non-Invasive Methods to Diagnose Fungal Infections in Pediatric Patients with Hematologic Disorders

    PubMed Central

    Badiee, Parisa; Hashemizadeh, Zahra; Ramzi, Mani; Karimi, Mohammad; Mohammadi, Rasoul

    2016-01-01

    Background Invasive fungal infection (IFIs) is a major infectious complication in immunocompromised patients. Early diagnosis and initiation of antifungal therapy is important to achieve the best outcome. Objectives The current study aimed to investigate the incidence of IFIs and evaluate the diagnostic performance of non-invasive laboratory tests: serologic (β-D-glucan, galactomannan) and molecular (nested polymerase chain reaction) tests to diagnose fungal infections in hematologic pediatric patients. Patients and Methods In a cross-sectional study from October 2014 to January 2015, 321 blood samples of 62 pediatric patients with hematologic disorders and at high risk for fungal infections were analyzed. Non-invasive tests including the Platelia Aspergillus enzyme immunoassay (EIA) to detect galactomannan antigen, Glucatell for β–D–glucan and nested PCR to detect Candida and Aspergillus species-specific DNA were used in a weekly screening strategy. Results Twenty six patients (42%) were considered as proven and probable IFIs, including 3 (5%) proven and 23 (37%) probable cases. Eighteen patients (29%) were considered as possible cases. The sensitivity, specificity, positive and negative predictive values for galactomannan test in 26 patients with proven and probable fungal infections were 94.4%, 100%, 100% and 94.7%; for β-D-glucan test 92.3%, 77.7%, 85%, 87.5% and for nested-PCR were 84.6%, 88.8%, 91.7% and 80%, respectively. Conclusions The rate of IFIs in pediatric patients with hematologic disorders is high, and sample collection from the sterile sites cannot be performed in immunocompromised patients. Detection of circulating fungal cell wall components and DNA in the blood using non-invasive methods can offer diagnostic help in patients with suspected IFIs. Their results should be interpreted in combination with clinical, radiological and microbiological findings. PMID:28138379

  7. Non-invasive measurements of tissue hemodynamics with hybrid diffuse optical methods

    NASA Astrophysics Data System (ADS)

    Durduran, Turgut

    Diffuse optical techniques were used to measure hemodynamics of tissues non-invasively. Spectroscopy and tomography of the brain, muscle and implanted tumors were carried out in animal models and humans. Two qualitatively different methods, diffuse optical tomography and diffuse correlation tomography, were hybridized permitting simultaneous measurement of total hemoglobin concentration, blood oxygen saturation and blood flow. This combination of information was processed further to derive estimates of oxygen metabolism (e.g. CMRO 2) in tissue. The diffuse correlation measurements of blood flow were demonstrated in human tissues, for the first time, demonstrating continous, non-invasive imaging of oxygen metabolism in large tissue volumes several centimeters below the tissue surface. The bulk of these investigations focussed on cerebral hemodynamics. Extensive validation of this methodology was carried out in in vivo rat brain models. Three dimensional images of deep tissue hemodynamics in middle cerebral artery occlusion and cortical spreading depression (CSD) were obtained. CSD hemodynamics were found to depend strongly on partial pressure of carbon dioxide. The technique was then adapted for measurement of human brain. All optical spectroscopic measurements of CMRO2 during functional activation were obtained through intact human skull non-invasively. Finally, a high spatio-temporal resolution measurement of cerebral blood flow due to somatosensory cortex activation following electrical forepaw stimulation in rats was carried out with laser speckle flowmetry. New analysis methods were introduced for laser speckle flowmetry. In other organs, deep tissue hemodynamics were measured on human calf muscle during exercise and cuff-ischemia and were shown to have some clinical utility for peripheral vascular disease. In mice tumor models, the measured hemodynamics were shown to be predictive of photodynamic therapy efficacy, again suggesting promise of clinical utility

  8. Genotyping approach for non-invasive foetal RHD detection in an admixed population

    PubMed Central

    Boggione, Carolina Trucco; Luján Brajovich, Melina E.; Mattaloni, Stella M.; Di Mónaco, René A.; García Borrás, Silvia E.; Biondi, Claudia S.; Cotorruelo, Carlos M.

    2017-01-01

    Background Non-invasive foetal RHD genotyping can predict haemolytic disease of the foetus and the newborn in pregnancies with anti-D alloantibodies and also avoid antenatal anti-D prophylaxis in pregnant women carrying an RHD negative foetus. Considering that the Argentine genetic background is the result of generations of intermixing between several ethnic groups, we evaluated the diagnostic performance of a non-invasive foetal RHD determination strategy to guide targeted antenatal RhD immunoprophylaxis. This algorithm is based on the analysis of four regions of the RHD gene in cell-free foetal DNA in maternal plasma and maternal and paternal RHD genotyping. Materials and methods DNA from 298 serologically D negative pregnant women between 19–28 weeks gestation were RHD genotyped. Foetal RHD status was determined by real-time PCR in 296 maternal plasma samples. In particular cases, RHDΨ and RHD-CE-Ds alleles were investigated in paternal DNA. Umbilical cord blood was collected at birth, and serological and molecular studies were performed. Results Of the 298 maternal samples, 288 were D−/RHD− and 10 D−/RHD+ (2 RHD*DAR; 5 RHD-CE-Ds; 3 RHDΨ). Plasma from RHD*DAR carriers was not analysed. Real-time PCR showed 210 RHD+ and 78 RHD− foetuses and 8 inconclusive results. In this latter group, paternal molecular studies were useful to report a RHD negative status in 5 foetuses while only 3 remained inconclusive. All the results, except one false positive due to a silent allele (RHD[581insG]), agreed with the neonatal typing performed in cord blood. Discussion The protocol used for non-invasive prenatal RHD genotyping proved to be suitable to determine foetal RHD status in our admixed population. The knowledge of the genetic background of the population under study and maternal and paternal molecular analysis can reduce the number of inconclusive results when investigating foetal RHD status. PMID:27136427

  9. Does non-invasive brain stimulation improve cognition in major depressive disorder? A systematic review.

    PubMed

    Tortella, Gabriel; Selingardi, Priscila M L; Moreno, Marina L; Veronezi, Beatriz P; Brunoni, Andre R

    2014-01-01

    Non-invasive brain stimulation (NIBS) techniques, such as repeated transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), have been increasingly used in different contexts to improve cognitive performance and ameliorate depression symptoms. Considering that major depression is usually accompanied by cognitive deficits, NIBS technique could be also helpful to improve cognition in depressed patients. In this systematic review, we researched for articles published in PubMed/MEDLINE from the first date available to June 2014 that assessed cognitive performance in patients with depression before and after NIBS. Out of 191 references, 25 (16 for rTMS and 9 for tDCS) studies matched our eligibility criteria. Non-invasive brain stimulation interventions, such as rTMS and tDCS seem to be a promising tool for cognitive enhancement in MDD, although several issues and biases (e.g., blinding issues, tests without correction for multiple comparisons, placebo effects and exploratory analyses, practice effects) hinder us to conclude that NIBS technique improve cognition in patients with depression. We discussed possible shortcomings of the included studies, such as the use of different depression treatment protocols, the possibility that some findings were false-positive results of the employed cognitive tasks and whether cognition improvement could have been an epiphenomenon secondary to depression improvement. To conclude, whereas these non-pharmacological, non-invasive techniques are particularly appealing for cognitive improvement in depression, further studies are still warranted to disentangle whether NIBS technique induce positive effects on cognition beyond their antidepressant effects.

  10. Health technology assessment of non-invasive interventions for weight loss and body shape in Iran

    PubMed Central

    Nojomi, Marzieh; Moradi-Lakeh, Maziar; Velayati, Ashraf; Naghibzadeh-Tahami, Ahmad; Dadgostar, Haleh; Ghorabi, Gholamhossein; Moradi-Joo, Mohammad; Yaghoubi, Mohsen

    2016-01-01

    Background: The burden of obesity and diet-related chronic diseases is increasing in Iran, and prevention and treatment strategies are needed to address this problem. The aim of this study was to determine the outcome, cost, safety and cost-consequence of non-invasive weight loss interventions in Iran. Methods: We performed a systematic review to compare non-invasive interventions (cryolipolysis and radiofrequency/ ultrasonic cavitation) with semi-invasive (lipolysis) and invasive (liposuction). A sensitive electronic searching was done to find available interventional studies. Reduction of abdomen circumference (cm), reduction in fat layer thickness (%) and weight reduction (kg) were outcomes of efficacy. Meta-analysis with random models was used for pooling efficacy estimates among studies with the same follow-up duration. Average cost per intervention was estimated based on the capital, maintenance, staff, consumable and purchase costs. Results: Of 3,111 studies identified in our reviews, 13 studies assessed lipolysis, 10 cryolipolysis and 8 considered radiofrequency. Nine studies with the same follow-up duration in three different outcome group were included in meta-analysis. Radiofrequency showed an overall pooled estimate of 2.7 cm (95% CI; 2.3-3.1) of mean reduction in circumference of abdomen after intervention. Pooled estimate of reduction in fat layer thickness was 78% (95% CI; 73%-83%) after Lipolysis and a pooled estimate of weight loss was 3.01 kg (95% CI; 2.3-3.6) after lipousuction. The cost analysis revealed no significant differences between the costs of these interventions. Conclusion: The present study showed that non-invasive interventions appear to have better clinical efficacy, specifically in the body shape measurement, and less cost compared to invasive intervention (liposuction) PMID:27390717

  11. Non-invasive studies of multiphase flow in process equipment. Positron emission particle tracking technique

    NASA Astrophysics Data System (ADS)

    Balakin, B. V.; Adamsen, T. C. H.; Chang, Y.-F.; Kosinski, P.; Hoffmann, A. C.

    2017-01-01

    Positron emission particle tracking (PEPT) is a novel experimental technique for non-invasive inspection of industrial fluid/particle flows. The method is based on the dynamic positioning of a positron-emitting, flowing object (particle) performed through the sensing of annihilation events and subsequent numerical treatment to determine the particle position. The present paper shows an integrated overview of PEPT studies which were carried out using a new PET scanner in the Bergen University Hospital to study multiphase flows in different geometric configurations.

  12. Luminescent Tension-Indicating Orthopedic Strain Gauges for Non-Invasive Measurements Through Tissue

    NASA Technical Reports Server (NTRS)

    Anker, Jeffrey (Inventor); Rogalski, Melissa (Inventor); Anderson, Dakota (Inventor); Heath, Jonathon (Inventor)

    2015-01-01

    Strain gauges that can provide information with regard to the state of implantable devices are described. The strain gauges can exhibit luminescence that is detectable through living tissue, and the detectable luminescent emission can vary according to the strain applied to the gauge. A change in residual strain of the device can signify a loss of mechanical integrity and/or loosening of the implant, and this can be non-invasively detected either by simple visual detection of the luminescent emission or through examination of the emission with a detector such as a spectrometer or a camera.

  13. [Reflections on the use of non-invasive mechanical ventilation in acute respiratory failure].

    PubMed

    Scala, Raffaele

    2012-12-01

    Given its prevalence into the clinical practice, non-invasive ventilation (NIV) can be included among the cornerstones of medicine. Just think of the acute applications of NIV which are in constant expansion, from COPD exacerbation to severe de novo hypoxemia, from postoperative distress to extra-hospital use in acute pulmonary edema, from ongoing support of interventional procedures to delicate strategies for end of life in terminally ill oncologic and non-oncologic patients. The thought should be focused on how, by whom, where and to whom is delivered this mode of artificial ventilation to avoid the risk of trivialization and flattening.

  14. Method for Non-Invasive Determination of Chemical Properties of Aqueous Solutions

    NASA Technical Reports Server (NTRS)

    Todd, Paul W. (Inventor); Jones, Alan (Inventor); Thomas, Nathan A. (Inventor)

    2016-01-01

    A method for non-invasively determining a chemical property of an aqueous solution is provided. The method provides the steps of providing a colored solute having a light absorbance spectrum and transmitting light through the colored solute at two different wavelengths. The method further provides the steps of measuring light absorbance of the colored solute at the two different transmitted light wavelengths, and comparing the light absorbance of the colored solute at the two different wavelengths to determine a chemical property of an aqueous solution.

  15. [Invasive and non-invasive ventilation in conflict with best palliative care in severe COPD].

    PubMed

    Mikesch, Martin; Reichenpfader, Peter

    2009-12-01

    This example of an 80-year-old patient with severe lung disease and respiratory failure demonstrates the difficult relationship between the patient's needs, physical symptoms, and social problems. This man decides after a prolonged and difficult in-patient treatment actively for home ventilation rather than die of respiratory failure. He opts for tracheostomy and invasive ventilation because he cannot handle non-invasive mask-ventilation sufficiently by himself. It requires professional communication and support to gain the acceptance of family and caregivers for home ventilation. A survey of existing data on end of life decision-making in end-stage lung disease is given.

  16. Multiphoton excited hemoglobin fluorescence and third harmonic generation for non-invasive microscopy of stored blood

    PubMed Central

    Saytashev, Ilyas; Glenn, Rachel; Murashova, Gabrielle A.; Osseiran, Sam; Spence, Dana; Evans, Conor L.; Dantus, Marcos

    2016-01-01

    Red blood cells (RBC) in two-photon excited fluorescence (TPEF) microscopy usually appear as dark disks because of their low fluorescent signal. Here we use 15fs 800nm pulses for TPEF, 45fs 1060nm pulses for three-photon excited fluorescence, and third harmonic generation (THG) imaging. We find sufficient fluorescent signal that we attribute to hemoglobin fluorescence after comparing time and wavelength resolved spectra of other expected RBC endogenous fluorophores: NADH, FAD, biliverdin, and bilirubin. We find that both TPEF and THG microscopy can be used to examine erythrocyte morphology non-invasively without breaching a blood storage bag. PMID:27699111

  17. Non-invasive measurements of granular flows by magnetic resonance imaging

    SciTech Connect

    Nakagawa, M.; Altobelli, S.A.; Caprihan, A.; Fukushima, E.; Jeong, E.K.

    1993-01-20

    Magnetic Resonance Imaging (MRI) was used to measure granular-flow in a partially filled, steadily rotating, long, horizontal cylinder. This non-invasive technique can yield statistically averaged two-dimensional concentrations and velocity profiles anywhere in the flow of suitable granular materials. First, rigid body motion of a cylinder fill with granular material was studied to confirm the validity of this method. Then, the density variation of the flowing layer where particles collide and dilate, and the depth of the flowing layer and the flow velocity profile were obtained as a function of the cylinder rotation rate.

  18. Intercomparison of techniques for the non-invasive measurement of bone mass

    SciTech Connect

    Cohn, S.H.

    1981-01-01

    A variety of methods are presently available for the non-invasive measurement of bone mass of both normal individuals and patients with metabolic disorders. Chief among these methods are radiographic techniques such as radiogrammetry, photon absorptiometry, computer tomography, Compton scattering and neutron activation analysis. In this review, the salient features of the bone measurement techniques are discussed along with their accuracy and precision. The advantages and disadvantages of the various techniques for measuring bone mass are summarized. Where possible, intercomparisons are made of the various techniques.

  19. Non-invasive imaging methods applied to neo- and paleontological cephalopod research

    NASA Astrophysics Data System (ADS)

    Hoffmann, R.; Schultz, J. A.; Schellhorn, R.; Rybacki, E.; Keupp, H.; Gerden, S. R.; Lemanis, R.; Zachow, S.

    2013-11-01

    Several non-invasive methods are common practice in natural sciences today. Here we present how they can be applied and contribute to current topics in cephalopod (paleo-) biology. Different methods will be compared in terms of time necessary to acquire the data, amount of data, accuracy/resolution, minimum-maximum size of objects that can be studied, of the degree of post-processing needed and availability. Main application of the methods is seen in morphometry and volumetry of cephalopod shells in order to improve our understanding of diversity and disparity, functional morphology and biology of extinct and extant cephalopods.

  20. [Non-invasive mechanical ventilation in postoperative patients. A clinical review].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive ventilation (NIV) is a method of ventilatory support that is increasing in importance day by day in the management of postoperative respiratory failure. Its role in the prevention and treatment of atelectasis is particularly important in the in the period after thoracic and abdominal surgeries. Similarly, in the transplanted patient, NIV can shorten the time of invasive mechanical ventilation, reducing the risk of infectious complications in these high-risk patients. It has been performed A systematic review of the literature has been performed, including examining the technical, clinical experiences and recommendations concerning the application of NIV in the postoperative period.

  1. [Amyotrophic neuralgia associated with bilateral phrenic paralysis treated with non-invasive mechanical ventilation].

    PubMed

    García García, María Del Carmen; Hernández Borge, Jacinto; Antona Rodríguez, María José; Pires Gonçalves, Pedro; García García, Gema

    2015-09-07

    Amyotrophic neuralgia is an uncommon neuropathy characterized by severe unilateral shoulder pain. Isolated or concomitant involvement of other peripheral motor nerves depending on the brachial plexus such as phrenic or laryngeal nerves is unusual(1). Its etiology is unknown, yet several explanatory factors have been proposed. Phrenic nerve involvement, either unilateral or bilateral, is exceedingly rare. Diagnosis relies on anamnesis, functional and imaging investigations and electromyogram. We report the case of a 48-year-old woman with a past history of renal transplantation due to proliferative glomerulonephritis with subsequent transplant rejection, who was eventually diagnosed with amyotrophic neuralgia with bilateral phrenic involvement, and who required sustained non-invasive mechanical ventilation.

  2. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  3. Non-invasive estimation of dissipation from non-equilibrium fluctuations in chemical reactions.

    PubMed

    Muy, S; Kundu, A; Lacoste, D

    2013-09-28

    We show how to extract an estimate of the entropy production from a sufficiently long time series of stationary fluctuations of chemical reactions. This method, which is based on recent work on fluctuation theorems, is direct, non-invasive, does not require any knowledge about the underlying dynamics and is applicable even when only partial information is available. We apply it to simple stochastic models of chemical reactions involving a finite number of states, and for this case, we study how the estimate of dissipation is affected by the degree of coarse-graining present in the input data.

  4. Non Invasive Assessment of Tissue Oxygenation and Blood Flow as a Tool for Staging Diabetes

    NASA Astrophysics Data System (ADS)

    Sujatha, N.; Anand, B. S. Suresh; Jayanthy, A. K.; Murthy, V. B. Narayana; Sheshadri; Poddar, Richa

    2011-10-01

    Diffuse reflectance spectroscopy and laser speckle imaging have been identified as an effective tool in characterizing/assessing tissue oxygenation and blood flow in real time tissues. In this paper we are exploring the possibility of finding out blood flow/oxygenation at different areas of feet of subjects with different levels of diabetes. Tissue blood flow is determined by assessing the contrast variations in the laser speckle image of the foot and tissue oxygenation is assessed by diffuse reflectance spectroscopy. A combination of both techniques offers an effective and purely non invasive mode of examination in the staging of Diabetes.

  5. Novel multi wavelength sensor concept to measure carboxy- and methemoglobin concentration non-invasively

    NASA Astrophysics Data System (ADS)

    Timm, Ulrich; Kraitl, Jens; Gewiss, Helge; Kamysek, Svend; Brock, Beate; Ewald, Hartmut

    2016-03-01

    This paper will describe a novel multi-wavelength photometric method to measure carboxyhemoglobin (COHb) and methemoglobin (MetHb) concentration non-invasively. COHb and MetHb are so called dysfunctional hemoglobin derivatives and they are not able to carry oxygen. Standard pulse oximeters are only able to measure two derivatives, namely oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb) but the presence of other derivatives in the blood may distort the readings. The paper presents a new approach of a noninvasive sensor system to measure COHb and MetHb and the validation in vivo and in vitro.

  6. Online estimation of respiratory mechanics in non-invasive pressure support ventilation: a bench model study.

    PubMed

    Mulqueeny, Qestra; Tassaux, Didier; Vignaux, Laurence; Jolliet, Philippe; Schindhelm, Klaus; Redmond, Stephen; Lovell, Nigel H

    2010-01-01

    An online algorithm for determining respiratory mechanics in patients using non-invasive ventilation (NIV) in pressure support mode was developed and embedded in a ventilator system. Based on multiple linear regression (MLR) of respiratory data, the algorithm was tested on a patient bench model under conditions with and without leak and simulating a variety of mechanics. Bland-Altman analysis indicates reliable measures of compliance across the clinical range of interest (± 11-18% limits of agreement). Resistance measures showed large quantitative errors (30-50%), however, it was still possible to qualitatively distinguish between normal and obstructive resistances. This outcome provides clinically significant information for ventilator titration and patient management.

  7. Non-invasive biological fluid matrices analysed to assess exposure to environmental tobacco smoke.

    PubMed

    Demkowska, Ilona; Polkowska, Zaneta; Namieśnik, Jacek

    2011-01-01

    Human biomonitoring (analysis of biological fluids) is increasingly being used for assessing exposure to environmental pollutants. Smoking tobacco is a significant source of indoor air pollution and is harmful to human health. The aim of this research was to find both the best non-invasive matrices (from among saliva, urine, semen and sweat) for evaluating environmental exposure to tobacco smoke and the relationships between thiocyanates (biomarkers of environmental tobacco smoke exposure) and other inorganic ions in these matrices collected from active and passive smokers and also non-smokers.

  8. Pretreatment Method Research of Near-Infrared Spectra in Blood Component Non-Invasive Measurement

    NASA Astrophysics Data System (ADS)

    Li, Li Na; Zhang, Guang Jun; Li, Qing Bo

    Blood component non-invasive measurement based on near-infrared (NIR) spectroscopy has become a favorite topic in the field of biomedicine. However, the various noises from instrument measurement and the varying background from absorption of other components (except target analyte) in blood are the main causes, which influenced the prediction accuracy of multivariable calibration. Thinking of backgrounds and noises are always found in high-scale approximation and low-scale detail coefficients. It is possible to identify them by wavelet transform (WT), which has multi-resolution trait and can break spectral signals into different frequency components retaining the same resolution as the original signal. Meanwhile, associating with a criterion of uninformative variable elimination (UVE), it is better to eliminate backgrounds and noises simultaneously and visually. Basic principle and application technology of this pretreatment method, wavelet transform with UVE criterion, were presented in this paper. Three experimental near-infrared spectra data sets, including aqueous solution with four components data sets, plasma data sets, body oral glucose tolerance test (OGTT) data sets, which, including glucose (the target analyte in this study), have all been used in this paper as examples to explain this pretreatment method. The effect of selected wavelength bands in the pretreatment process were discussed, and then the adaptability of different pretreatment method for the uncertainty complex NIR spectra model in blood component non-invasive measurements were also analyzed. This research indicates that the pretreatment methods of wavelet transform with UVE criterion can be used to eliminate varying backgrounds and noises for experimental NIR spectra data directly. Under the spectra area of 1100 to 1700 nm, utilizing this pretreatment method is helpful for us to get a more simple and higher precision multivariable calibration for blood glucose non-invasive measurement

  9. Instrumented cardiac microphysiological devices via multimaterial three-dimensional printing.

    PubMed

    Lind, Johan U; Busbee, Travis A; Valentine, Alexander D; Pasqualini, Francesco S; Yuan, Hongyan; Yadid, Moran; Park, Sung-Jin; Kotikian, Arda; Nesmith, Alexander P; Campbell, Patrick H; Vlassak, Joost J; Lewis, Jennifer A; Parker, Kevin K

    2017-03-01

    Biomedical research has relied on animal studies and conventional cell cultures for decades. Recently, microphysiological systems (MPS), also known as organs-on-chips, that recapitulate the structure and function of native tissues in vitro, have emerged as a promising alternative. However, current MPS typically lack integrated sensors and their fabrication requires multi-step lithographic processes. Here, we introduce a facile route for fabricating a new class of instrumented cardiac microphysiological devices via multimaterial three-dimensional (3D) printing. Specifically, we designed six functional inks, based on piezo-resistive, high-conductance, and biocompatible soft materials that enable integration of soft strain gauge sensors within micro-architectures that guide the self-assembly of physio-mimetic laminar cardiac tissues. We validated that these embedded sensors provide non-invasive, electronic readouts of tissue contractile stresses inside cell incubator environments. We further applied these devices to study drug responses, as well as the contractile development of human stem cell-derived laminar cardiac tissues over four weeks.

  10. Instrumented cardiac microphysiological devices via multimaterial three-dimensional printing

    NASA Astrophysics Data System (ADS)

    Lind, Johan U.; Busbee, Travis A.; Valentine, Alexander D.; Pasqualini, Francesco S.; Yuan, Hongyan; Yadid, Moran; Park, Sung-Jin; Kotikian, Arda; Nesmith, Alexander P.; Campbell, Patrick H.; Vlassak, Joost J.; Lewis, Jennifer A.; Parker, Kevin K.

    2016-10-01

    Biomedical research has relied on animal studies and conventional cell cultures for decades. Recently, microphysiological systems (MPS), also known as organs-on-chips, that recapitulate the structure and function of native tissues in vitro, have emerged as a promising alternative. However, current MPS typically lack integrated sensors and their fabrication requires multi-step lithographic processes. Here, we introduce a facile route for fabricating a new class of instrumented cardiac microphysiological devices via multimaterial three-dimensional (3D) printing. Specifically, we designed six functional inks, based on piezo-resistive, high-conductance, and biocompatible soft materials that enable integration of soft strain gauge sensors within micro-architectures that guide the self-assembly of physio-mimetic laminar cardiac tissues. We validated that these embedded sensors provide non-invasive, electronic readouts of tissue contractile stresses inside cell incubator environments. We further applied these devices to study drug responses, as well as the contractile development of human stem cell-derived laminar cardiac tissues over four weeks.

  11. Cardiac catheterization

    MedlinePlus

    Catheterization - cardiac; Heart catheterization; Angina - cardiac catheterization; CAD - cardiac catheterization; Coronary artery disease - cardiac catheterization; Heart valve - cardiac catheterization; Heart failure - ...

  12. The Cardiac Stress Response Factor Ms1 Can Bind to DNA and Has a Function in the Nucleus

    PubMed Central

    Kho, Ay Lin; Ababou, Abdessamad; Ehler, Elisabeth; Pfuhl, Mark

    2015-01-01

    Ms1 (also known as STARS and ABRA) has been shown to act as an early stress response gene in processes as different as hypertrophy in skeletal and cardiac muscle and growth of collateral blood vessels. It is important for cardiac development in zebrafish and is upregulated in mouse models for cardiac hypertrophy as well as in human failing hearts. Ms1 possesses actin binding sites at its C-terminus and is usually found in the cell bound to actin filaments in the cytosol or in sarcomeres. We determined the NMR structure of the only folded domain of Ms1 comprising the second actin binding site called actin binding domain 2 (ABD2, residues 294–375), and found that it is similar to the winged helix-turn-helix fold adopted mainly by DNA binding domains of transcriptional factors. In vitro experiments show specific binding of this domain, in combination with a newly discovered AT-hook motif located N-terminally, to the sequence (A/C/G)AAA(C/A). NMR and fluorescence titration experiments confirm that this motif is indeed bound specifically by the recognition helix. In neonatal rat cardiomyocytes endogenous Ms1 is found in the nucleus in a spotted pattern, reminiscent of PML bodies. In adult rat cardiomyocytes Ms1 is exclusively found in the sarcomere. A nuclear localisation site in the N-terminus of the protein is required for nuclear localisation. This suggests that Ms1 has the potential to act directly in the nucleus through specific interaction with DNA in development and potentially as a response to stress in adult tissues. PMID:26656831

  13. Cardioprotective role of Syzygium cumini against glucose-induced oxidative stress in H9C2 cardiac myocytes.

    PubMed

    Atale, Neha; Chakraborty, Mainak; Mohanty, Sujata; Bhattacharya, Susinjan; Nigam, Darshika; Sharma, Manish; Rani, Vibha

    2013-09-01

    Diabetic patients are known to have an independent risk of cardiomyopathy. Hyperglycemia leads to upregulation of reactive oxygen species (ROS) that may contribute to diabetic cardiomyopathy. Thus, agents that suppress glucose-induced intracellular ROS levels can have therapeutic potential against diabetic cardiomyopathy. Syzygium cumini is well known for its anti-diabetic potential, but its cardioprotective properties have not been evaluated yet. The aim of the present study is to analyze cardioprotective properties of methanolic seed extract (MSE) of S. cumini in diabetic in vitro conditions. ROS scavenging activity of MSE was studied in glucose-stressed H9C2 cardiac myoblasts after optimizing the safe dose of glucose and MSE by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. 2',7'-dichlorfluorescein diacetate staining and Fluorescence-activated cell sorting analysis confirmed the suppression of ROS production by MSE in glucose-induced cells. The intracellular NO and H2O2 radical-scavenging activity of MSE was found to be significantly high in glucose-induced cells. Exposure of glucose-stressed H9C2 cells to MSE showed decline in the activity of catalase and superoxide dismutase enzymes and collagen content. 4',6-diamidino-2-phenylindole, propidium iodide and 10-N-nonyl-3,6-bis (dimethylamino) acridine staining revealed that MSE protects myocardial cells from glucose-induced stress. Taken together, our findings revealed that the well-known anti-diabetic S. cumini can also protect the cardiac cells from glucose-induced stress.

  14. Non-invasive spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags.

    PubMed

    Buckley, K; Atkins, C G; Chen, D; Schulze, H G; Devine, D V; Blades, M W; Turner, R F B

    2016-03-07

    After being separated from (donated) whole blood, red blood cells are suspended in specially formulated additive solutions and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until they are needed for transfusion. With time, the prepared red cell concentrate (RCC) is known to undergo biochemical changes that lower effectiveness of the transfusion, and thus regulations are in place that limit the storage period to 42 days. At present, RCC is not subjected to analytical testing prior to transfusion. In this study, we use Spatially Offset Raman Spectroscopy (SORS) to probe, non-invasively, the biochemistry of RCC inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. In addition to the analytical demonstration that SORS can be used to retrieve RCC spectra from standard clinical blood-bags without breaking the sterility of the system, the data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RCC degeneration, and points the way to a Raman-based instrument for quality-control in a blood-bank or hospital setting.

  15. High-precision, non-invasive anti-microvascular approach via concurrent ultrasound and laser irradiation

    PubMed Central

    Hu, Zizhong; Zhang, Haonan; Mordovanakis, Aghapi; Paulus, Yannis M.; Liu, Qinghuai; Wang, Xueding; Yang, Xinmai

    2017-01-01

    Antivascular therapy represents a proven strategy to treat angiogenesis. By applying synchronized ultrasound bursts and nanosecond laser irradiation, we developed a novel, selective, non-invasive, localized antivascular method, termed photo-mediated ultrasound therapy (PUT). PUT takes advantage of the high native optical contrast among biological tissues and can treat microvessels without causing collateral damage to the surrounding tissue. In a chicken yolk sac membrane model, under the same ultrasound parameters (1 MHz at 0.45 MPa and 10 Hz with 10% duty cycle), PUT with 4 mJ/cm2 and 6 mJ/cm2 laser fluence induced 51% (p = 0.001) and 37% (p = 0.018) vessel diameter reductions respectively. With 8 mJ/cm2 laser fluence, PUT would yield vessel disruption (90%, p < 0.01). Selectivity of PUT was demonstrated by utilizing laser wavelengths at 578 nm or 650 nm, where PUT selectively shrank veins or occluded arteries. In a rabbit ear model, PUT induced a 68.5% reduction in blood perfusion after 7 days (p < 0.001) without damaging the surrounding cells. In vitro experiments in human blood suggested that cavitation may play a role in PUT. In conclusion, PUT holds significant promise as a novel non-invasive antivascular method with the capability to precisely target blood vessels. PMID:28074839

  16. Optical coherence tomography: a non-invasive technique applied to conservation of paintings

    NASA Astrophysics Data System (ADS)

    Liang, Haida; Gomez Cid, Marta; Cucu, Radu; Dobre, George; Kudimov, Boris; Pedro, Justin; Saunders, David; Cupitt, John; Podoleanu, Adrian

    2005-06-01

    It is current practice to take tiny samples from a painting to mount and examine in cross-section under a microscope. However, since conservation practice and ethics limit sampling to a minimum and to areas along cracks and edges of paintings, which are often unrepresentative of the whole painting, results from such analyses cannot be taken as representative of a painting as a whole. Recently in a preliminary study, we have demonstrated that near-infrared Optical Coherence Tomography (OCT) can be used directly on paintings to examine the cross-section of paint and varnish layers without contact and the need to take samples. OCT is an optical interferometric technique developed for in vivo imaging of the eye and biological tissues; it is essentially a scanning Michelson's interferometer with a "broad-band" source that has the spatial coherence of a laser. The low temporal coherence and high spatial concentration of the source are the keys to high depth resolution and high sensitivity 3D imaging. The technique is non-invasive and non-contact with a typical working distance of 2 cm. This non-invasive technique enables cross-sections to be examined anywhere on a painting. In this paper, we will report new results on applying near-infrared en-face OCT to paintings conservation and extend the application to the examination of underdrawings, drying processes, and quantitative measurements of optical properties of paint and varnish layers.

  17. Non-invasive, serum DNA pregnancy testing leading to incidental discovery of cancer: a good thing?

    PubMed

    Prasad, Vinay

    2015-11-01

    Cell-free DNA for perinatal screening is a growing industry. Non-invasive prenatal testing (NIPT) is based on the premise that foetal DNA is able to cross the placental barrier and enter the mother's circulation, where it can be examined for chromosomal abnormalities, such as trisomy 13, 18 or 21. Such tests are expected to be widely used by pregnant women, with the annual market expected to surpass $1 billion. Recently, a number of case reports have emerged in the haematology-oncology literature. The routine use of NIPT has led to the discovery of maternal neoplasms. Most writers have concluded that this is yet another benefit of the test; however, a closer examination of the cases reveals that this incidental detection may not improve patient outcomes. In some cases, early detection provides lead time bias, but does not change the ultimate clinical outcome, and in other cases, detection constitutes earlier knowledge of a cancer whose natural history cannot be altered. Here, we explore in detail cases where cancer was incidentally discovered among women undergoing routine non-invasive pregnancy testing, and investigate whether or not these women were benefitted by the discovery.

  18. Non-invasive assessment of liver fibrosis in patients with alcoholic liver disease

    PubMed Central

    Lombardi, Rosa; Buzzetti, Elena; Roccarina, Davide; Tsochatzis, Emmanuel A

    2015-01-01

    Alcoholic liver disease (ALD) consists of a broad spectrum of disorders, ranging from simple steatosis to alcoholic steatohepatitis and cirrhosis. Fatty liver develops in more than 90% of heavy drinkers, however only 30%-35% of them develop more advanced forms of ALD. Therefore, even if the current “gold standard” for the assessment of the stage of alcohol-related liver injury is histology, liver biopsy is not reasonable in all patients who present with ALD. Currently, although several non-invasive fibrosis markers have been suggested as alternatives to liver biopsy in patients with ALD, none has been sufficiently validated. As described in other liver disease, the diagnostic accuracy of such tests in ALD is acceptable for the diagnosis of significant fibrosis or cirrhosis but not for lesser fibrosis stages. Existing data suggest that the use of non-invasive tests could be tailored to first tier screening of patients at risk, in order to diagnose early patients with progressive liver disease and offer targeted interventions for the prevention of decompensation. We review these tests and critically appraise the existing evidence. PMID:26494961

  19. Mouse models in neurological disorders: applications of non-invasive imaging.

    PubMed

    Waerzeggers, Yannic; Monfared, Parisa; Viel, Thomas; Winkeler, Alexandra; Jacobs, Andreas H

    2010-10-01

    Neuroimaging techniques represent powerful tools to assess disease-specific cellular, biochemical and molecular processes non-invasively in vivo. Besides providing precise anatomical localisation and quantification, the most exciting advantage of non-invasive imaging techniques is the opportunity to investigate the spatial and temporal dynamics of disease-specific functional and molecular events longitudinally in intact living organisms, so called molecular imaging (MI). Combining neuroimaging technologies with in vivo models of neurological disorders provides unique opportunities to understand the aetiology and pathophysiology of human neurological disorders. In this way, neuroimaging in mouse models of neurological disorders not only can be used for phenotyping specific diseases and monitoring disease progression but also plays an essential role in the development and evaluation of disease-specific treatment approaches. In this way MI is a key technology in translational research, helping to design improved disease models as well as experimental treatment protocols that may afterwards be implemented into clinical routine. The most widely used imaging modalities in animal models to assess in vivo anatomical, functional and molecular events are positron emission tomography (PET), magnetic resonance imaging (MRI) and optical imaging (OI). Here, we review the application of neuroimaging in mouse models of neurodegeneration (Parkinson's disease, PD, and Alzheimer's disease, AD) and brain cancer (glioma).

  20. Non-invasive Quantification of Whole-brain Cerebral Metabolic Rate of Oxygen by MRI

    PubMed Central

    Xu, Feng; Ge, Yulin; Lu, Hanzhang

    2009-01-01

    Cerebral metabolic rate of oxygen (CMRO2) is an important marker for brain function and brain health. Existing techniques for quantification of CMRO2 with Positron Emission Tomography (PET) or MRI involve special equipment and/or exogenous agent, and may not be suitable for routine clinical studies. In the present study, a non-invasive method is developed to estimate whole-brain CMRO2 in humans. This method applies phase-contrast MRI for quantitative blood flow measurement and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI for venous oxygenation estimation, and uses the Fick principle of arteriovenous difference for the calculation of CMRO2. Whole-brain averaged CMRO2 values in young, healthy subjects were 132.1±20.0 μmol/100g/min, in good agreement with literature reports using PET. Various acquisition strategies for phase-contrast and TRUST MRI were compared, and it was found that non-gated phase-contrast and sagittal sinus TRUST MRI were able to provide the most efficient and accurate estimation of CMRO2. In addition, blood flow and venous oxygenation were found to be positively correlated across subjects. Owing to the non-invasive nature of this method, it may be a convenient and useful approach for assessment of brain metabolism in brain disorders as well as under various physiologic conditions. PMID:19353674

  1. Distribution of emm types in invasive and non-invasive group A and G streptococci.

    PubMed

    Vähäkuopus, S; Vuento, R; Siljander, T; Syrjänen, J; Vuopio, J

    2012-06-01

    Our study describes the emm type distributions of invasive and non-invasive group A streptococci (GAS) and group G streptococci (GGS) strains in one of the biggest Health Districts in Finland. A total of 571 GAS or GGS were recovered from patients with invasive or non-invasive infections during a 1-year period in 2008-2009 in Pirkanmaa Health District in Finland. We describe here the emm type distributions of GAS and GGS collected from throat (n = 246), pus (n = 217), deep tissue (n = 56) and blood (n = 52). The most common emm types among GAS were emm77, emm1, emm28, emm89 and emm12. Among GGS, the most common emm types were stG480, stG643, stG6, stC6979 and stG485. Some emm types were found to associate with certain infection focus. In GAS, emm77 associated with pus isolates, whereas emm1 and emm12 were more frequent among throat isolates. In GGS, stG480 was more commonly found from throat isolates.

  2. A phantom with pulsating artificial vessels for non-invasive fetal pulse oximetry.

    PubMed

    Laqua, Daniel; Pollnow, Stefan; Fischer, Jan; Ley, Sebastian; Husar, Peter

    2014-01-01

    Arterial oxygen saturation of the fetus is an important parameter for monitoring its physical condition. During labor and delivery the transabdominal non-invasive fetal pulse oximetry could minimize the risk for mother and fetus, compared to other existing invasive examination methods. In this contribution, we developed a physical-like phantom to investigate new sensor circuits and algorithms of a non-invasive diagnostic method for fetal pulse oximetry. Hence, the developed artificial vascular system consists of two independent tube systems representing the maternal and fetal vessel system. The arterial blood pressure is reproduced with a pre-pressure and an artificial vascular system. Each pulse wave can be reproduced, by digital control of a proportional valve, adjustable viscoelastic elements, and resistances. The measurements are performed by pressure transducers, optical sensor units, and a coplanar capacitive sensor. Transmission and reflection measurements have shown that the fetal and maternal pulse waves can be reproduced qualitatively. The measured light represents the transabdominal modulated signal on an abdomen of a pregnant woman.

  3. A rapid, non-invasive procedure for quantitative assessment of drought survival using chlorophyll fluorescence

    PubMed Central

    Woo, Nick S; Badger, Murray R; Pogson, Barry J

    2008-01-01

    Background Analysis of survival is commonly used as a means of comparing the performance of plant lines under drought. However, the assessment of plant water status during such studies typically involves detachment to estimate water shock, imprecise methods of estimation or invasive measurements such as osmotic adjustment that influence or annul further evaluation of a specimen's response to drought. Results This article presents a procedure for rapid, inexpensive and non-invasive assessment of the survival of soil-grown plants during drought treatment. The changes in major photosynthetic parameters during increasing water deficit were monitored via chlorophyll fluorescence imaging and the selection of the maximum efficiency of photosystem II (Fv/Fm) parameter as the most straightforward and practical means of monitoring survival is described. The veracity of this technique is validated through application to a variety of Arabidopsis thaliana ecotypes and mutant lines with altered tolerance to drought or reduced photosynthetic efficiencies. Conclusion The method presented here allows the acquisition of quantitative numerical estimates of Arabidopsis drought survival times that are amenable to statistical analysis. Furthermore, the required measurements can be obtained quickly and non-invasively using inexpensive equipment and with minimal expertise in chlorophyll fluorometry. This technique enables the rapid assessment and comparison of the relative viability of germplasm during drought, and may complement detailed physiological and water relations studies. PMID:19014425

  4. Non-invasive aerosol delivery and transport of gold nanoparticles to the brain

    PubMed Central

    Raliya, Ramesh; Saha, Debajit; Chadha, Tandeep S.; Raman, Baranidharan; Biswas, Pratim

    2017-01-01

    Targeted delivery of nanoscale carriers containing packaged payloads to the central nervous system has potential use in many diagnostic and therapeutic applications. Moreover, understanding of the bio-interactions of the engineered nanoparticles used for tissue-specific delivery by non-invasive delivery approaches are also of paramount interest. Here, we have examined this issue systematically in a relatively simple invertebrate model using insects. We synthesized 5 nm, positively charged gold nanoparticles (AuNPs) and targeted their delivery using the electrospray aerosol generator. Our results revealed that after the exposure of synthesized aerosol to the insect antenna, AuNPs reached the brain within an hour. Nanoparticle accumulation in the brain increased linearly with the exposure time. Notably, electrophysiological recordings from neurons in the insect brain several hours after exposure did not show any significant alterations in their spontaneous and odor-evoked spiking properties. Taken together, our findings reveal that aerosolized delivery of nanoparticles can be an effective non-invasive approach for delivering nanoparticles to the brain, and also presents an approach to monitor the short-term nano-biointeractions. PMID:28300204

  5. Diagnostic and prognostic utility of non-invasive imaging in diabetes management

    PubMed Central

    Barsanti, Cristina; Lenzarini, Francesca; Kusmic, Claudia

    2015-01-01

    Medical imaging technologies are acquiring an increasing relevance to assist clinicians in diagnosis and to guide management and therapeutic treatment of patients, thanks to their non invasive and high resolution properties. Computed tomography, magnetic resonance imaging, and ultrasonography are the most used imaging modalities to provide detailed morphological reconstructions of tissues and organs. In addition, the use of contrast dyes or radionuclide-labeled tracers permits to get functional and quantitative information about tissue physiology and metabolism in normal and disease state. In recent years, the development of multimodal and hydrid imaging techniques is coming to be the new frontier of medical imaging for the possibility to overcome limitations of single modalities and to obtain physiological and pathophysiological measurements within an accurate anatomical framework. Moreover, the employment of molecular probes, such as ligands or antibodies, allows a selective in vivo targeting of biomolecules involved in specific cellular processes, so expanding the potentialities of imaging techniques for clinical and research applications. This review is aimed to give a survey of characteristics of main diagnostic non-invasive imaging techniques. Current clinical appliances and future perspectives of imaging in the diagnostic and prognostic assessment of diabetic complications affecting different organ systems will be particularly addressed. PMID:26131322

  6. Fur: A non-invasive approach to monitor metal exposure in bats.

    PubMed

    Hernout, Béatrice V; McClean, Colin J; Arnold, Kathryn E; Walls, Michael; Baxter, Malcolm; Boxall, Alistair B A

    2016-03-01

    This paper presents a novel assessment of the use of fur as a non-invasive proxy to biomonitor metal contamination in insectivorous bats. Concentrations of metals (cadmium, copper, lead and zinc) were measured using ICP-MS in tissues (kidneys, liver, stomach and stomach content, bones and fur) obtained from 193 Pipistrellus pipistrellus/pygmaeus bats. The bats were collected across a gradient of metal pollution in England and Wales. The utility of small samples of fur as an indicator of metal exposure from the environment was demonstrated with strong relationships obtained between the concentrations of non-essential metals in fur with concentrations in stomach content, kidneys, liver and bones. Stronger relationships were observed for non-essential metals than for essential metals. Fur analyses might therefore be a useful non-invasive proxy for understanding recent, as well as long term and chronic, metal exposure of live animals. The use of fur may provide valuable information on the level of endogenous metal exposure and contamination of bat populations and communities.

  7. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines

    PubMed Central

    Busschots, Steven; O’Toole, Sharon; O’Leary, John J.; Stordal, Britta

    2014-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. • Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner. • The technique is quick, affordable and eliminates sample manipulation. • The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines. PMID:26150966

  8. Non-invasive prenatal testing using cell-free fetal DNA in maternal circulation.

    PubMed

    Liao, Gary J W; Gronowski, Ann M; Zhao, Zhen

    2014-01-20

    The identification of cell-free fetal DNA (cffDNA) in maternal circulation has made non-invasive prenatal testing (NIPT) possible. Maternal plasma cell free DNA is a mixture of maternal and fetal DNA, of which, fetal DNA represents a minor population in maternal plasma. Therefore, methods with high sensitivity and precision are required to detect and differentiate fetal DNA from the large background of maternal DNA. In recent years, technical advances in the molecular analysis of fetal DNA (e.g., digital PCR and massively parallel sequencing (MPS)) has enabled the successful implementation of noninvasive testing into clinical practice, such as fetal sex assessment, RhD genotyping, and fetal chromosomal aneuploidy detection.With the ability to decipher the entire fetal genome from maternal plasma DNA, we foresee that an increased number of non-invasive prenatal tests will be available for detecting many single-gene disorders in the near future. This review briefly summarizes the technical aspects of the NIPT and application of NIPT in clinical practice.

  9. Non-Invasive Assessment of Liver Fibrosis Progression and Prognosis in Primary Biliary Cholangitis.

    PubMed

    Poupon, Raoul

    2015-01-01

    PBC (formerly known as primary biliary cirrhosis and now named primary biliary cholangitis) is a disease with a wide range of severity and variable rate of progression. The diagnosis of advanced liver fibrosis/cirrhosis portends an increased risk of liver-related morbidity and mortality. Because of its invasiveness, liver biopsy tends to be replaced by non-invasive tools for assessing liver fibrosis, making prognosis and optimising risk stratification for selection of patients, requiring new medical approaches. Many direct or indirect biomarkers have been found to correlate with the severity of liver fibrosis in PBC. They are easy to use but lack sensitivity and reproducibility in individuals with early stage disease. Three main radiologic approaches are currently proposed to assess liver fibrosis: vibration controlled transient elastography (VCTE), acoustic radiation force impulse and magnetic resonance elastography. Data using VCTE are available only for the longitudinal evaluation of liver fibrosis and prognosis in PBC. VCTE outperformed all other non-invasive current surrogate markers of liver fibrosis in PBC. Because of its high acceptability and its ability to predict hepatic decompensation, VCTE could be a useful tool to help allocate cirrhotic patients into different categories of risk. None of the radiologic and serum markers have a perfect accuracy in studies so far published. Concordance between VCTE and serum biomarkers is a prerequisite for a correct prognosis assessment in individuals in clinical practice.

  10. A servo-mechanical load frame for in situ, non-invasive, imaging of damage development

    SciTech Connect

    Breunig, T.M.; Nichols, M.C.; Gruver, J.S.; Kinney, J.H.; Haupt, D.L.

    1993-12-31

    The X-ray tomographic microscope (XTM) is a non-invasive X-ray imaging instrument for characterizing a material`s structure three-dimensionally with microscopic spatial resolution. The authors have designed a servomechanical load frame for use with the XTM which will allow imaging of samples under load. The load frame is capable of generating tensile or compressive forces up to 15.6 kN with a design system stiffness of 8.76 {times} 10{sup 8} N/m. The test specimen can be rotated through 360{degree}, without induced bending or torque. Torqueless motion is accomplished by synchronously rotating the grips on precision bearings with an accuracy of 0.01{degree}. With this load frame it will be possible, for the first time, to image the initiation and accumulation of internal damage (0.5 {mu}m detectability) formed in a 6 mm diameter specimen during the application of a monotonic or low frequency cyclic load. This is accomplished by interrupting the test and maintaining a fixed load (or displacement) during the non-invasive XTM data collection procedure. This paper describes the in situ load frame design and experimental capabilities. This system can be used to enhance the understanding of failure in composite materials.

  11. Breath Analysis as a Potential and Non-Invasive Frontier in Disease Diagnosis: An Overview

    PubMed Central

    Pereira, Jorge; Porto-Figueira, Priscilla; Cavaco, Carina; Taunk, Khushman; Rapole, Srikanth; Dhakne, Rahul; Nagarajaram, Hampapathalu; Câmara, José S.

    2015-01-01

    Currently, a small number of diseases, particularly cardiovascular (CVDs), oncologic (ODs), neurodegenerative (NDDs), chronic respiratory diseases, as well as diabetes, form a severe burden to most of the countries worldwide. Hence, there is an urgent need for development of efficie