Photoplethysmographic waves and their detailed pulse interval distribution analysis on Poincare plots before and after the sauna exposures

Carotid baroreceptors were stimulated with graded neck suction in supine and standing volunteers, before and after autonomic blockade, to determine the influence of posture on baroreflex responsiveness. Propranolol significantly augmented baroreflex pulse interval prolongation in the supine position. Upright posture did not modify baroreflex pulse interval responses prior to propranolol, but significantly augmented responses after propranolol. The results suggest that standing enhances baroreflex sensitivity, but that under normal circumstances, this effect is masked by beta-adrenergic stimulation. Augmentation of baroreflex pulse interval prolongation in the supine and standing positions by propranolol may contribute to the effectiveness of this drug in angina pectoris and labile hypertension.

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Imaging and Methotrexate Response Monitoring of Systemic Inflammation in Arthritic Rats Employing the Macrophage PET Tracer [18F]Fluoro-PEG-Folate

Contrast Media & Molecular Imaging ◽

10.1155/2018/8092781 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Durga M. S. H. Chandrupatla ◽

Gerrit Jansen ◽

Elise Mantel ◽

Philip S. Low ◽

Takami Matsuyama ◽

...

Keyword(s):

Systemic Inflammation ◽

Pet Imaging ◽

Ex Vivo ◽

Folate Receptor ◽

Tracer Uptake ◽

Response Monitoring ◽

Distribution Analysis ◽

Pet Tracer ◽

Systemic Inflammatory Disease ◽

Before And After

Background. In rheumatoid arthritis, articular inflammation is a hallmark of disease, while the involvement of extra-articular tissues is less well defined. Here, we examined the feasibility of PET imaging with the macrophage tracer [18F]fluoro-PEG-folate, targeting folate receptorβ(FRβ), to monitor systemic inflammatory disease in liver and spleen of arthritic rats before and after methotrexate (MTX) treatment.Methods. [18F]Fluoro-PEG-folate PET scans (60 min) were acquired in saline- and MTX-treated (1 mg/kg, 4x) arthritic rats, followed by tissue resection and radiotracer distribution analysis. Liver and spleen tissues were stained for ED1/ED2-macrophage markers and FRβexpression.Results. [18F]Fluoro-PEG-folate PET and ex vivo tissue distribution studies revealed a significant (p<0.01) 2-fold lower tracer uptake in both liver and spleen of MTX-treated arthritic rats. Consistently, ED1- and ED2-positive macrophages were significantly (p<0.01) decreased in liver (4-fold) and spleen (3-fold) of MTX-treated compared with saline-treated rats. Additionally, FRβ-positive macrophages were also significantly reduced in liver (5-fold,p<0.005) and spleen (3-fold,p<0.01) of MTX- versus saline-treated rats.Conclusions. MTX treatment reduced activated macrophages in liver and spleen, as markers for systemic inflammation in these organs. Macrophage PET imaging with [18F]fluoro-PEG-folate holds promise for detection of systemic inflammation in RA as well as therapy (MTX) response monitoring.

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Chaotization of Human Systems by Technical Electromagnetic Fields

Handbook of Research on Distributed Medical Informatics and E-Health ◽

10.4018/978-1-60566-002-8.ch035 ◽

2009 ◽

pp. 493-499

Author(s):

Manfred Doepp

Keyword(s):

Magnetic Field ◽

Skin Resistance ◽

Autonomous Systems ◽

Distribution Analysis ◽

Bell Curve ◽

Switching Phenomenon ◽

Significant Difference ◽

Before And After ◽

Reaction Patterns ◽

Synchronization Procedure

In our energy diagnostic department we noticed more and more cases with irrational stimulus-reaction- patterns and with a chaotic regulation state of the autonomous systems. We found an explanation by the ‘Switching phenomenon’. However, in addition to earlier results a new cause came up, it is the electrosmog exposure. We used three criteria to clarify the findings: A) a negative reaction on a pulsating magnetic field, B) a positive reaction on a brain synchronization procedure, and C) the frequency distribution analysis of skin resistance values approximated by a lognormal (order) or by a bell curve (chaos). A retrospective evaluation over 4 years (435 patients) was performed. Results: 1) a positive correlation between the criterium A) and a chaotic tendency in C), and 2) a significant difference between reactions before and after the synchronization procedure B). The hypothesis of an electrosmog-induced chaotization of autonomous systems becomes likely.

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Single-channel analysis of a K channel at basolateral membrane of rabbit proximal convoluted tubule

AJP Renal Physiology ◽

10.1152/ajprenal.1988.254.1.f105 ◽

1988 ◽

Vol 254 (1) ◽

pp. F105-F113 ◽

Cited By ~ 4

Author(s):

L. Parent ◽

J. Cardinal ◽

R. Sauve

Keyword(s):

Single Channel ◽

Basolateral Membrane ◽

Proximal Convoluted Tubule ◽

Time Interval ◽

Distribution Analysis ◽

Patch Clamp Technique ◽

Bathing Medium ◽

Patch Pipette ◽

K Concentration ◽

Interval Distribution

The basolateral membrane of the rabbit proximal convoluted tubule (PCT) is known to be largely permeable to K ions. The patch-clamp technique was used to investigate the molecular basis of this K permeability. At room temperature and with a high-K solution (127 mM) in both the bathing medium and the patch pipette, current jumps associated with an inward-rectifying channel could be detected in every active cell-attached experiment. When the K concentration in the pipette was changed from 200 to 5 mM KCl (NaCl replacement), the single-channel conductance for inward currents changed from 54 to 10 pS. The observed shift in the zero current potential measured as a function of the patch pipette K concentration could be fitted using the Goldman-Hodgkin-Katz equation with a permeability ratio PNa/PK = 0.06. The channel was found to be moderately voltage dependent (e-fold per 56 mV depolarization). For instance, the open-channel probability (Po) increased from 0.06 to 0.16 following a membrane depolarization from -50 to +50 mV. A time interval distribution analysis showed for the open state a dominant single time constant of 14 and 10 ms at 50 and -50 mV, respectively. Two time constants equal to 1 (flickering) and 26 ms at +50 mV and to 0.6 and 300 ms at -50 mV were obtained for the closed-state interval distribution. Based on this analysis, it was concluded that the decrease of Po at negative potentials was due more to the appearance of prolonged silent periods than from a change in the channel mean open time.

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Hemodynamic correlates of effective arterial elastance in mitral stenosis before and after balloon valvotomy

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.4.1083 ◽

1997 ◽

Vol 83 (4) ◽

pp. 1083-1089 ◽

Cited By ~ 4

Author(s):

Patrice Colin ◽

Michel Slama ◽

Alec Vahanian ◽

Yves Lecarpentier ◽

Gilbert Motté ◽

...

Keyword(s):

Mitral Stenosis ◽

Arterial Compliance ◽

Aortic Pressure ◽

Pulse Interval ◽

Wave Reflections ◽

Arterial Elastance ◽

Before And After ◽

Hydraulic Load ◽

Balloon Valvotomy ◽

Effective Arterial Elastance

Colin, Patrice, Michel Slama, Alec Vahanian, Yves Lecarpentier, Gilbert Motté, and Denis Chemla. Hemodynamic correlates of effective arterial elastance in mitral stenosis before and after balloon valvotomy. J. Appl. Physiol. 83(4): 1083–1089, 1997.—This study had the purpose of documenting the hemodynamic correlates of effective arterial elastance (Ea; i.e., an accurate estimate of hydraulic load) in mitral stenosis (MS) patients. The main hypothesis tested was that Ea relates to the total vascular resistance (R)-to-pulse interval duration ( T) ratio (R/ T) in MS patients both before and after successful balloon mitral valvotomy (BMV). High-fidelity aortic pressure recordings were obtained in 10 patients (40 ± 12 yr) before and 15 min after BMV. Ea value was calculated as the ratio of the steady-state end-systolic aortic pressure (ESAP) to stroke volume (thermodilution). Ea increased after BMV (from 1.55 ± 0.63 to 1.83 ± 0.71 mmHg/ml; P < 0.05). Throughout the procedure, there was a strong linear relationship between Ea and R/ T: Ea = 1.09R/ T − 0.01 mmHg/ml, r = 0.99, P = 0.0001. This ultimately depended on the powerful link between ESAP and mean aortic pressure [MAP; r = 0.99, 95% confidence interval for the difference (MAP − ESAP) from −18.5 to +4.5 mmHg]. Ea was also related to total arterial compliance (area method) and to wave reflections (augmentation index), although to a lesser extent. After BMV, enhanced and anticipated wave reflections were observed, and this was likely to be explained by decreased arterial compliance. The present study indicated that Ea depended mainly on the steady component of hydraulic load (i.e., R) and on heart period (i.e., T) in MS patients.

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P4491Noninvasive evaluation of force distribution in mitral annuloplasty rings: do rigid annuloplasty rings increase stress?

European Heart Journal ◽

10.1093/eurheartj/ehz745.0884 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

E Ovcharenko ◽

K Y U Klyshnikov ◽

A Kokov ◽

T Glushkova ◽

L S Barbarash

Keyword(s):

Mitral Annulus ◽

Force Distribution ◽

Distribution Analysis ◽

Initial State ◽

Element Analysis ◽

Mitral Annuloplasty ◽

Jude Medical ◽

Average Deformation ◽

Before And After ◽

Invasive Method

Abstract Purpose To evaluate forces distribution, local stresses and deformation of mitral annuloplasty rings in response to annuloplasty. Methods Seguin (St. Jude Medical), Physio I (Edwards LifeScience), Memo 3D (Sorin) and Future SG (Medtronic) MAR of size 30 mm were included in the study. The study group included 4 males patients aged 52–68 years who underwent isolated mitral valve annuloplasty for ischemic mitral regurgitation. All surgeries were performed by the same experienced operator according to the standardized protocol. The mechanical properties of the similar set of MAR were evaluated under uniaxial compression by 15% in the longitudinal and transverse directions on the Testing Machines Z5.0 (Zwick/Roell). Biomechanics was assessed with MSCT. The MAR frame models at the initial state and at the ventricular ejection and atrial systole phases were obtained from DICOM-data using computer tomography Sensation Somatom 64 (Siemens). The models were compared using the innovative numerical algorithm in MatLab (Mathworks) by forming pairs for “systole – diastole”, “initial state – diastole” for all four types of MAR. We compared the mobility of the implanted devices and changes in the physiological saddle shape geometry of the mitral annulus in response to annuloplasty. We performed the quantitative analysis of the movement of each point of the reconstructed model between two states with the subsequent calculation of the required forces based on the finite element analysis. Results Future CG MAR has the greatest longitudinal and transverse stiffness (18.1N and 4.8N, respectively), whereas Memo 3D demonstrates the lowest values (2.3N and 1.5N). The rest two models show intermediate values of 4.2 - 11.3 N to 2.0 - 4.3N. The comparative analysis of MAR before and after implantation shows that Physio demonstrates the most pronounced deviations from normal physiological shape with significant annular compression along the intercommissural diameter by 1.36 mm resulted in a rounded annulus shape. None significant geometrical deformity among the other prosthetic rings. MEMO 3D demonstrates an average deformation by 0.18 mm across all zones, Seguin - 0.42 mm, Future CG - 0.34 mm. The force distribution analysis demonstrated the least forces of MEMO 3D, whereas the largest ones (up to 1.5N) are shown by Future SG, leading to the induction of locally elevated stress in surrounding tissues, potentially triggering the development of paravalvular fistulae. Conclusion Preliminary results demonstrate that the use of flexible rings with initially mobile structure allows preserving the native mitral annulus mobility after annuloplasty and reducing the stress (forces) acting on the surrounding tissues. The presented non-invasive method for estimating the stress of mitral annulus is crucial for advanced clinical practice as it allows further studying of the underlying pathologic mechanisms of developing paravalvular fistulae.

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In the Adult Male Rhesus Monkey (Macaca mulatta), Unilateral Orchidectomy in the Face of Unchanging Gonadotropin Stimulation Results in Partial Compensation of Testosterone Secretion by the Remaining Testis

Endocrinology ◽

10.1210/en.2004-0824 ◽

2004 ◽

Vol 145 (11) ◽

pp. 5115-5120 ◽

Cited By ~ 5

Author(s):

David R. Simorangkir ◽

Suresh Ramaswamy ◽

Gary R. Marshall ◽

Tony M. Plant

Keyword(s):

Leydig Cells ◽

Pulse Interval ◽

Gonadotropin Secretion ◽

Testosterone Secretion ◽

Independent Mechanism ◽

Before And After ◽

The Face ◽

Pulsatile Infusion ◽

Male Rhesus ◽

Partial Compensation

Abstract This study examined, in adult monkeys, the role that gonadotropin-independent mechanisms play in compensation of testosterone (T) secretion by the testis that remains after unilateral orchidectomy (UO). We employed a model (testicular clamp), in which endogenous gonadotropin secretion was abolished with a GnRH receptor antagonist, and the gonadotropin drive to the testes was concomitantly replaced with an invariant iv pulsatile infusion of recombinant human LH and FSH (1-min pulse every 2.5 h: LH, 0.08–0.12 IU/kg·pulse; FSH, 0.12–0.32 IU/kg·pulse) that provided the Leydig cells with a physiological stimulus. Within 5 h of UO (n = 5), circulating T concentrations had declined to 43% of pre-UO levels. By d 4, however, loss of the first testis was partially compensated, as reflected by the finding that circulating T had reached a plateau of 67% of the pre-UO level, where it remained for the duration of the study (39 d). That the recovery in circulating T was the result of increased T secretion by the remaining testis was suggested by the finding that the pulsatile pattern and decay of T during the intergonadotropin pulse interval before and after UO were indistinguishable. Interestingly, inhibin B production by the remaining testis also showed a delayed, albeit, minor, compensation (13% on d 10–11; P > 0.05) after loss of the first testis. These results suggest that compensation in T production by the remaining testis after UO in adult monkeys may be achieved in part by a gonadotropin-independent mechanism that probably involves direct neural inputs to the primate testis.

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Influence of ovarian manipulation on reproductive endocrinology in polycystic ovarian syndrome and regularly cycling women

Acta Endocrinologica ◽

10.1530/eje-13-0334 ◽

2013 ◽

Vol 169 (4) ◽

pp. 503-510 ◽

Cited By ~ 3

Author(s):

M L Hendriks ◽

T König ◽

R S Soleman ◽

T Korsen ◽

R Schats ◽

...

Keyword(s):

Polycystic Ovarian Syndrome ◽

Transvaginal Ultrasound ◽

Ovarian Hormones ◽

Pulse Interval ◽

Hormonal Changes ◽

Before And After ◽

Mechanical Manipulation ◽

Lh Secretion ◽

Late Follicular Phase ◽

Ovarian Syndrome

ObjectiveLittle is known about the function of the ovarian neuronal network in humans. In many species, copulation influences endocrinology through this network. As a first step, the possible influence of ovarian mechanical manipulation on pituitary and ovarian hormones was evaluated in polycystic ovarian syndrome (PCOS) and regularly cycling women. DesignProspective case–control study (2008–2010).MethodsTen PCOS women (Rotterdam criteria) undergoing ovulation induction with recombinant-FSH and ten normal ovulatory controls were included in an academic fertility clinic. In the late follicular phase blood was drawn every 10 min for 6 h. After 3 h the ovaries were mechanically manipulated by moving a transvaginal ultrasound probe firmly over each ovary ten times. Main outcome measures were LH and FSH pulsatility and ovarian hormones before and after ovarian manipulation.ResultsAll PCOS patients showed an LH decline after the ovarian manipulation (before 13.0 U/l and after 10.4 U/l, P<0.01), probably based on a combination of a longer LH pulse interval and smaller amplitude (P=0.07). The controls showed no LH change (before 9.6 U/l and after 9.3 U/l, P=0.67). None of the ovarian hormones (estradiol, progesterone, anti-Müllerian hormone, inhibin B, androstenedione and testosterone) changed in either group.ConclusionsOvarian mechanical manipulation lowers LH secretion immediately and typically only in preovulatory PCOS patients. The immediate LH change after the ovarian manipulation without any accompanying ovarian hormonal changes point to nonhormonal communication from the ovaries to the pituitary. A neuronal pathway from the ovaries communicating to the hypothalamic–pituitary system is the most reasonable explanation.

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Sodium channel enhancer restores baroreflex sensitivity in conscious dogs with heart failure

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00337.2004 ◽

2005 ◽

Vol 288 (4) ◽

pp. H1508-H1514 ◽

Cited By ~ 5

Author(s):

Weiqun Shen ◽

Robert M. Gill ◽

Jian-Ping Zhang ◽

Bonita D. Jones ◽

Angela K. Corbly ◽

...

Keyword(s):

Heart Failure ◽

Arterial Pressure ◽

Baroreflex Sensitivity ◽

Vena Cava ◽

Left Ventricular ◽

Conscious Dogs ◽

Inotropic Effect ◽

Pulse Interval ◽

Adrenergic Blockade ◽

Before And After

We compared the cardiac inotropic, lusitropic, and chronotropic responses to the Na+ channel enhancer LY-368052 in conscious dogs before and after development of congestive heart failure (CHF). We also examined the effect of LY-368052 on baroreflex sensitivity and the efferent neural mechanisms of the bradycardic response in heart failure. Dogs were chronically instrumented, and heart failure was induced by right ventricular pacing at 240 beats/min for 3–4 wk. LY-368052 dose-dependently increased left ventricular contractile performance before and after the development of CHF to a similar extent. The inotropic effect of LY-368052 in heart failure was not altered by either ganglionic or β-adrenergic receptor blockade. LY-368052 improved cardiac relaxation and induced bradycardia in dogs with heart failure but not in normal dogs. The negative chronotropic effect of LY-368052 was eliminated by ganglionic blockade but not β-adrenergic blockade, suggesting that the bradycardia was mediated by the autonomic nervous system via enhanced parasympathetic tone. Baroreflex sensitivity was assessed as the pulse interval-mean arterial pressure slope in response to temporary pharmacological (nitroglycerin or phenylephrine) and mechanical (brief occlusion of inferior vena cava) alterations of arterial pressure in conscious dogs before and after development of heart failure. Baroreflex sensitivity was significantly depressed in heart failure and restored completely by acute treatment with LY-368052. Thus the Na+ channel enhancer LY-368052 maintains its β-receptor-independent inotropic effect in chronic CHF and specifically improves ventricular relaxation and depressed baroreflex function.

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Critical Appraisal of Indices for the Assessment of Baroreflex Sensitivity

Methods of Information in Medicine ◽

10.1055/s-0038-1636857 ◽

1997 ◽

Vol 36 (04/05) ◽

pp. 246-249 ◽

Cited By ~ 12

Author(s):

P. Castiglioni ◽

G. Mancia ◽

G. Parati ◽

A. Pedotti ◽

M. Di Rienzo

Keyword(s):

Blood Pressure ◽

Baroreflex Sensitivity ◽

Critical Appraisal ◽

Spectral Estimation ◽

Respiratory Frequency ◽

Pulse Interval ◽

Alpha Coefficient ◽

Before And After ◽

Reliable Parameter ◽

Spontaneous Baroreflex

Abstract:The sequence technique and the spectral estimation of the alpha coefficient are currently employed for the assessment of “spontaneous” baroreflex sensitivity (BRS). The comparison of performance and effectiveness of these techniques is obtained by the analysis of systolic blood pressure (SBP) and pulse interval (PI) tracings recorded in conscious cats before and after baroreceptor denervation. Results indicate that (1) the average BRS estimates obtained by the sequence technique and by the alpha coefficient at the respiratory frequency are similar, (2) the alpha coefficients computed at the respiratory frequency tend to be higher than alpha coefficients estimated at 0.1 Hz, and (3) in spite of what is traditionally claimed, the PI-SBP coherence does not seem to represent a reliable parameter to enhance the specificity of the spectral estimate, because coherence values often remain above the 0.5 threshold also after baroreceptor denervation.

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