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Sample records for bipolar pacemaker current

  1. Does bipolar pacemaker current activate blood platelets?

    DEFF Research Database (Denmark)

    Gjesdal, Grunde; Hansen, Annebirthe Bo; Brandes, Axel

    2009-01-01

    OBJECTIVE: The aim of this study was to investigate whether bipolar pacemaker current lead can activate blood platelets. The null hypothesis was that 1 minute of electrical stimulation of platelets would not influence their subsequent reactivity to adenosine diphosphate (ADP). BACKGROUND: Both...... platelets and muscle cells contain actin and myosin filaments, and both cells are activated following calcium influx. Muscle cells open their calcium channels and contract when exposed to an electric current. Current through a bipolar pacemaker lead will expose a small volume of blood, including platelets......, to the depolarizing current. Platelet activation may ensue, resulting in aggregation, release reaction, and contraction. In contrast, a unipolar pacemaker system will not depolarize blood, but transmit current directly into the myocardium, and the current afterward passes through other tissues before returning...

  2. Influence of internal current and pacing current on pacemaker longevity.

    Science.gov (United States)

    Schuchert, A; Kuck, K H

    1994-01-01

    The effects of lower pulse amplitude on battery current and pacemaker longevity were studied comparing the new, small-sized VVI pacemaker, Minix 8341, with the former model, Pasys 8329. Battery current was telemetrically measured at 0.8, 1.6, 2.5, and 5.0 V pulse amplitude and 0.05, 0.25, 0.5, and 1.0 msec pulse duration. Internal current was assumed to be equal to the battery current at 0.8 V and 0.05 msec. Pacing current was calculated subtracting internal current from battery current. The Minix pacemaker had a significantly lower battery current because of a lower internal current (Minix: 4.1 +/- 0.1 microA; Pasys: 16.1 +/- 0.1 microA); pacing current of both units was similar. At 0.5 msec pulse duration, the programming from 5.0-2.5 V pulse amplitude resulted in a greater relative reduction of battery current in the newer pacemaker (51% vs 25%). Projected longevity of each pacemaker was 7.9 years at 5.0 V and 0.5 msec. The programming from 5.0-2.5 V extended the projected longevity by 2.3 years (Pasys) and by 7.1 years (Minix). The longevity was negligibly longer after programming to 1.6 V. extension of pacemaker longevity can be achieved with the programming to 2.5 V or less if the connected pacemakers need a low internal current for their circuitry.

  3. Ventricular fibrillation induced by coagulating mode bipolar electrocautery during pacemaker implantation in Myotonic Dystrophy type 1 patient.

    Science.gov (United States)

    Russo, Vincenzo; Rago, Anna; DI Meo, Federica; Cioppa, Nadia Della; Papa, Andrea Antonio; Russo, Maria Giovanna; Nigro, Gerardo

    2014-12-01

    The occurrence of ventricular fibrillation, induced by bipolar electrocautery during elective dual chamber pacemaker implantation, is reported in a patient affected by Myotonic Distrophy type 1 with normal left ventricular ejection fraction.

  4. Pacemaker

    Science.gov (United States)

    ... close to a security system metal detector. Notify security staff if you have a pacemaker. Also, stay at least 2 feet away from industrial welders and electrical generators. Some medical procedures can ...

  5. Leadless Cardiac Pacemakers: Current status of a modern approach in pacing

    Directory of Open Access Journals (Sweden)

    Skevos Sideris

    2017-11-01

    Full Text Available Since the first transvenous pacemaker implantation, which took place 50 years ago, important progress has been achieved in pacing technology. Consequently, at present, more than 700,000 pacemakers are implanted annually worldwide. However, conventional pacemakers' implantation has a non-negligible risk of periprocedural and long-term complications associated with the transvenous leads and pacemaker pocket. Recently, leadless pacing systems have emerged as a therapeutic alternative to conventional pacing systems that provide therapy for patients with bradyarrhythmias, while eliminating potential transvenous lead- and pacemaker pocket-related complications. Initial studies have demonstrated favorable efficacy and safety of currently developed leadless pacing systems, compared to transvenous pacemakers. In the present paper, we review the current evidence and highlight the advantages and disadvantages of this novel technology. New technological advances may allow the next generation of leadless pacemakers to further expand, thereby offering a wireless cardiac pacing in future. Keywords: cardiac pacing, pacemaker, leadless pacemaker, bradycardia

  6. Heart pacemaker

    Science.gov (United States)

    Cardiac pacemaker implantation; Artificial pacemaker; Permanent pacemaker; Internal pacemaker; Cardiac resynchronization therapy; CRT; Biventricular pacemaker; Arrhythmia - pacemaker; Abnormal heart ...

  7. Calcium Transient and Sodium-Calcium Exchange Current in Human versus Rabbit Sinoatrial Node Pacemaker Cells

    Directory of Open Access Journals (Sweden)

    Arie O. Verkerk

    2013-01-01

    Full Text Available There is an ongoing debate on the mechanism underlying the pacemaker activity of sinoatrial node (SAN cells, focusing on the relative importance of the “membrane clock” and the “Ca2+ clock” in the generation of the small net membrane current that depolarizes the cell towards the action potential threshold. Specifically, the debate centers around the question whether the membrane clock-driven hyperpolarization-activated current, If, which is also known as the “funny current” or “pacemaker current,” or the Ca2+ clock-driven sodium-calcium exchange current, INaCa, is the main contributor to diastolic depolarization. In our contribution to this journal’s “Special Issue on Cardiac Electrophysiology,” we present a numerical reconstruction of If and INaCa in isolated rabbit and human SAN pacemaker cells based on experimental data on action potentials, If, and intracellular calcium concentration ([Ca2+]i that we have acquired from these cells. The human SAN pacemaker cells have a smaller If, a weaker [Ca2+]i transient, and a smaller INaCa than the rabbit cells. However, when compared to the diastolic net membrane current, INaCa is of similar size in human and rabbit SAN pacemaker cells, whereas If is smaller in human than in rabbit cells.

  8. Pacemaker neuron and network oscillations depend on a neuromodulator-regulated linear current

    Directory of Open Access Journals (Sweden)

    Shunbing Zhao

    2010-05-01

    Full Text Available Linear leak currents have been implicated in the regulation of neuronal excitability, generation of neuronal and network oscillations, and network state transitions. Yet, few studies have directly tested the dependence of network oscillations on leak currents or explored the role of leak currents on network activity. In the oscillatory pyloric network of decapod crustaceans neuromodulatory inputs are necessary for pacemaker activity. A large subset of neuromodulators is known to activate a single voltage-gated inward current IMI, which has been shown to regulate the rhythmic activity of the network and its pacemaker neurons. Using the dynamic clamp technique, we show that the crucial component of IMI for the generation of oscillatory activity is only a close-to-linear portion of the current-voltage relationship. The nature of this conductance is such that the presence or the absence of neuromodulators effectively regulates the amount of leak current and the input resistance in the pacemaker neurons. When deprived of neuromodulatory inputs, pyloric oscillations are disrupted; yet, a linear reduction of the total conductance in a single neuron within the pacemaker group recovers not only the pacemaker activity in that neuron, but also leads to a recovery of oscillations in the entire pyloric network. The recovered activity produces proper frequency and phasing that is similar to that induced by neuromodulators. These results show that the passive properties of pacemaker neurons can significantly affect their capacity to generate and regulate the oscillatory activity of an entire network, and that this feature is exploited by neuromodulatory inputs.

  9. Pacemaker Dependency after Cardiac Surgery: A Systematic Review of Current Evidence.

    Science.gov (United States)

    Steyers, Curtis M; Khera, Rohan; Bhave, Prashant

    2015-01-01

    Severe postoperative conduction disturbances requiring permanent pacemaker implantation frequently occur following cardiac surgery. Little is known about the long-term pacing requirements and risk factors for pacemaker dependency in this population. We performed a systematic review of the literature addressing rates and predictors of pacemaker dependency in patients requiring permanent pacemaker implantation after cardiac surgery. Using a comprehensive search of the Medline, Web of Science and EMBASE databases, studies were selected for review based on predetermined inclusion and exclusion criteria. A total of 8 studies addressing the endpoint of pacemaker-dependency were identified, while 3 studies were found that addressed the recovery of atrioventricular (AV) conduction endpoint. There were 10 unique studies with a total of 780 patients. Mean follow-up ranged from 6-72 months. Pacemaker dependency rates ranged from 32%-91% and recovery of AV conduction ranged from 16%-42%. There was significant heterogeneity with respect to the definition of pacemaker dependency. Several patient and procedure-specific variables were found to be independently associated with pacemaker dependency, but these were not consistent between studies. Pacemaker dependency following cardiac surgery occurs with variable frequency. While individual studies have identified various perioperative risk factors for pacemaker dependency and non-resolution of AV conduction disease, results have been inconsistent. Well-conducted studies using a uniform definition of pacemaker dependency might identify patients who will benefit most from early permanent pacemaker implantation after cardiac surgery.

  10. Heart pacemaker - discharge

    Science.gov (United States)

    Cardiac pacemaker implantation - discharge; Artificial pacemaker - discharge; Permanent pacemaker - discharge; Internal pacemaker - discharge; Cardiac resynchronization therapy - discharge; CRT - discharge; ...

  11. Dynamic, nonlinear feedback regulation of slow pacemaking by A-type potassium current in ventral tegmental area neurons.

    Science.gov (United States)

    Khaliq, Zayd M; Bean, Bruce P

    2008-10-22

    We analyzed ionic currents that regulate pacemaking in dopaminergic neurons of the mouse ventral tegmental area by comparing voltage trajectories during spontaneous firing with ramp-evoked currents in voltage clamp. Most recordings were made in brain slice, with key experiments repeated using acutely dissociated neurons, which gave identical results. During spontaneous firing, net ionic current flowing between spikes was calculated from the time derivative of voltage multiplied by cell capacitance, signal-averaged over many firing cycles to enhance resolution. Net inward interspike current had a distinctive nonmonotonic shape, reaching a minimum (generally current that peaked near -55 mV. This current was undetectable with 5 mV/s ramps and increased steeply with depolarization rate over the range (10-50 mV/s) typical of natural pacemaking. Ramp-evoked subthreshold current was resistant to alpha-dendrotoxin, paxilline, apamin, and tetraethylammonium but sensitive to 4-aminopyridine and 0.5 mM Ba2+, consistent with A-type potassium current (I(A)). Same-cell comparison of currents elicited by various ramp speeds with natural spontaneous depolarization showed how the steep dependence of I(A) on depolarization rate results in small net inward currents during pacemaking. These results reveal a mechanism in which subthreshold I(A) is near zero at steady state, but is engaged at depolarization rates >10 mV/s to act as a powerful, supralinear feedback element. This feedback mechanism explains how net ionic current can be constrained to <1-2 pA but reliably inward, thus enabling slow, regular firing.

  12. Pacemaker (image)

    Science.gov (United States)

    A pacemaker is a small, battery-operated electronic device which is inserted under the skin to help the heart beat regularly and at an appropriate rate. The pacemaker has leads that travel through a large vein ...

  13. Current irritability robustly related to current and prior anxiety in bipolar disorder.

    Science.gov (United States)

    Yuen, Laura D; Miller, Shefali; Wang, Po W; Hooshmand, Farnaz; Holtzman, Jessica N; Goffin, Kathryn C; Shah, Saloni; Ketter, Terence A

    2016-08-01

    Although current irritability and current/prior anxiety have been associated in unipolar depression, these relationships are less well understood in bipolar disorder (BD). We investigated relationships between current irritability and current/prior anxiety as well as other current emotions and BD illness characteristics. Outpatients referred to the Stanford Bipolar Disorders Clinic during 2000-2011 were assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation. Prevalence and clinical correlates of current irritability and current/prior anxiety and other illness characteristics were examined. Among 497 BD outpatients (239 Type I, 258 Type II; 58.1% female; mean ± SD age 35.6 ± 13.1 years), 301 (60.6%) had baseline current irritability. Patients with versus without current irritability had significantly higher rates of current anxiety (77.1% versus 42.9%, p anxiety disorder (73.1% versus 52.6%, p anxiety than to current anhedonia, sadness, or euphoria (all p anxiety associations persisted across current predominant mood states. Current irritability was more robustly related to past anxiety than to all other assessed illness characteristics, including 1° family history of mood disorder, history of alcohol/substance use disorder, bipolar subtype, and current syndromal/subsyndromal depression (all p anxiety. Further studies are warranted to assess longitudinal clinical implications of relationships between irritability and anxiety in BD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Low cost bipolar current collector-separator for electrochemical cells

    International Nuclear Information System (INIS)

    Lawrence, R.

    1980-01-01

    A bipolar current collecting, cell separating element for electrochemical cells for conducting current from the anode electrode of one cell unit to cathode electrode of the adjacent cell unit comprises: (A) a pressure mold aggregate of electrically conductive carbon/graphite particles and thermoplastic fluorocarbon polymer resin particles in a weight ratio of 2.5:1 to 16:1 whereby said molded aggregated has a bulk resistivity which is less than 4x10 -3 ohm/inch, (B) said molded aggregate having a fluid imprevious main body, at least one recessed chamber on one side of said main body and a plurality of spaced, conductive projections extending from the base of said chamber for contacting and permitting current flow between the electrode of adjacent cell unit, and (C) means communicating with said recessed chambers to permit introduction and removal of fluids

  15. Cardiac Pacemakers

    International Nuclear Information System (INIS)

    Fiandra, O.; Espasandin, W.; Fiandra, H.

    1984-01-01

    A complete survey of physiological biophysical,clinical and engineering aspects of cardiac facing,including the history and an assessment of possible future developments.Among the topics studied are: pacemakers, energy search, heart stimulating with pacemakers ,mathematical aspects of the electric cardio stimulation chronic, pacemaker implants,proceeding,treatment and control

  16. Evidences of the ultrarapid delayed rectifier potassium current (IKur on pacemaker activity in sinoatrial and atrioventricular nodes of Rat

    Directory of Open Access Journals (Sweden)

    Mohammad reza Nikmaram

    2008-09-01

    Full Text Available Background: Sinoatrial node (SAN is the primary pacemaker of the heart. If the SAN activity fails in any way, then the atrioventricular node (AVN immediately starts to regulate the activities of the heart. The aim of this study was to assess the existence or non existence of ultrarapid delayed rectifier potassium current (Ikur and its role on pacemaker activity of two intact SAN and AVN of rat. Methods: The pacemaker activities of distinct intact SAN and AVN by two separate metal microelectrodes that contact the endothelial surface of nodes were recorded and cycle length (CL of action potential was measured. The recording was done before and during 50µM 4-Aminopyridine (4-AP as an Ikur blocker. Results: Compared to control condition, CL of action potentials of SAN and VAN preparations had increased by 17.60 +/-2.9% and 35.90 +/-2.9%, respectively (P<0.05. Conclusion: It is possible to conclude that the Ikur was present in AVN and SAN and the effect of 4-AP on CL of action potential nodes was significantly different.

  17. Intracellular Ca(2+) release from endoplasmic reticulum regulates slow wave currents and pacemaker activity of interstitial cells of Cajal.

    Science.gov (United States)

    Zhu, Mei Hong; Sung, Tae Sik; O'Driscoll, Kate; Koh, Sang Don; Sanders, Kenton M

    2015-04-15

    Interstitial cells of Cajal (ICC) provide pacemaker activity in gastrointestinal muscles that underlies segmental and peristaltic contractions. ICC generate electrical slow waves that are due to large-amplitude inward currents resulting from anoctamin 1 (ANO1) channels, which are Ca(2+)-activated Cl(-) channels. We investigated the hypothesis that the Ca(2+) responsible for the stochastic activation of ANO1 channels during spontaneous transient inward currents (STICs) and synchronized activation of ANO1 channels during slow wave currents comes from intracellular Ca(2+) stores. ICC, obtained from the small intestine of Kit(+/copGFP) mice, were studied under voltage and current clamp to determine the effects of blocking Ca(2+) uptake into stores and release of Ca(2+) via inositol 1,4,5-trisphosphate (IP3)-dependent and ryanodine-sensitive channels. Cyclocpiazonic acid, thapsigargin, 2-APB, and xestospongin C inhibited STICs and slow wave currents. Ryanodine and tetracaine also inhibited STICs and slow wave currents. Store-active compounds had no direct effects on ANO1 channels expressed in human embryonic kidney-293 cells. Under current clamp, store-active drugs caused significant depolarization of ICC and reduced spontaneous transient depolarizations (STDs). After block of ryanodine receptors with ryanodine and tetracaine, repolarization did not restore STDs. ANO1 expressed in ICC has limited access to cytoplasmic Ca(2+) concentration, suggesting that pacemaker activity depends on Ca(2+) dynamics in restricted microdomains. Our data from studies of isolated ICC differ somewhat from studies on intact muscles and suggest that release of Ca(2+) from both IP3 and ryanodine receptors is important in generating pacemaker activity in ICC. Copyright © 2015 the American Physiological Society.

  18. Intracellular Ca2+ release from endoplasmic reticulum regulates slow wave currents and pacemaker activity of interstitial cells of Cajal

    Science.gov (United States)

    Zhu, Mei Hong; Sung, Tae Sik; O'Driscoll, Kate; Koh, Sang Don

    2015-01-01

    Interstitial cells of Cajal (ICC) provide pacemaker activity in gastrointestinal muscles that underlies segmental and peristaltic contractions. ICC generate electrical slow waves that are due to large-amplitude inward currents resulting from anoctamin 1 (ANO1) channels, which are Ca2+-activated Cl− channels. We investigated the hypothesis that the Ca2+ responsible for the stochastic activation of ANO1 channels during spontaneous transient inward currents (STICs) and synchronized activation of ANO1 channels during slow wave currents comes from intracellular Ca2+ stores. ICC, obtained from the small intestine of Kit+/copGFP mice, were studied under voltage and current clamp to determine the effects of blocking Ca2+ uptake into stores and release of Ca2+ via inositol 1,4,5-trisphosphate (IP3)-dependent and ryanodine-sensitive channels. Cyclocpiazonic acid, thapsigargin, 2-APB, and xestospongin C inhibited STICs and slow wave currents. Ryanodine and tetracaine also inhibited STICs and slow wave currents. Store-active compounds had no direct effects on ANO1 channels expressed in human embryonic kidney-293 cells. Under current clamp, store-active drugs caused significant depolarization of ICC and reduced spontaneous transient depolarizations (STDs). After block of ryanodine receptors with ryanodine and tetracaine, repolarization did not restore STDs. ANO1 expressed in ICC has limited access to cytoplasmic Ca2+ concentration, suggesting that pacemaker activity depends on Ca2+ dynamics in restricted microdomains. Our data from studies of isolated ICC differ somewhat from studies on intact muscles and suggest that release of Ca2+ from both IP3 and ryanodine receptors is important in generating pacemaker activity in ICC. PMID:25631870

  19. Correlates of current suicide risk among Thai patients with bipolar I disorder: findings from the Thai Bipolar Disorder Registry

    Directory of Open Access Journals (Sweden)

    Suttajit S

    2013-11-01

    Full Text Available Sirijit Suttajit,1 Suchat Paholpak,2 Somrak Choovanicvong,3 Khanogwan Kittiwattanagul,4 Wetid Pratoomsri,5 Manit Srisurapanont1On behalf of the Thai Bipolar Registry Group1Department of Psychiatry, Chiang Mai University, Chiang Mai, 2Department of Psychiatry, Khon Kaen University, Khon Kaen, 3Srithanya Hospital, Nonthaburi, 4Khon Kaen Rajanagarindra Psychiatric Hospital, Khon Kaen, 5Chachoengsao Hospital, Chachoengsao, ThailandBackground: The Thai Bipolar Disorder Registry was a prospective, multisite, naturalistic study conducted in 24 hospitals across Thailand. This study aimed to examine the correlates of current suicide risk in Thai patients with bipolar I disorder.Methods: Participants were adult inpatients or outpatients with bipolar disorder, based on the Diagnosis and Statistical Manual of Mental Disorders, fourth edition. All were assessed by using the Mini International Neuropsychiatric Interview (MINI, version 5. The severity of current suicide risk was determined by using the total score of the MINI suicidality module. Mood symptoms were assessed by using the Young Mania Rating Scale and the Montgomery Asberg Depression Rating Scale.Results: The data of 383 bipolar I disorder patients were included in the analyses. Of these, 363 (94.8% were outpatients. The mean (standard deviation of the MINI suicide risk score was 1.88 (5.0. The demographic/clinical variables significantly associated with the MINI suicide risk scores included age, number of overall previous episodes, the Young Mania Rating Scale score, the Montgomery Asberg Depression Rating Scale scores, and the Clinical Global Impression Severity of Illness Scale for Bipolar Disorder mania score, depression score, and overall score. The variables affecting the differences of suicide risk scores between or among groups were type of first mood episode, a history of rapid cycling, anxiety disorders, and alcohol use disorders. The stepwise multiple linear regression model revealed

  20. Ionizing radiation effects on implanted pacemakers

    International Nuclear Information System (INIS)

    Holzer, J.; Aiginger, H.; Binder, W.

    1998-01-01

    Fourteen multi-programmable pacemakers and 2 intercardial defibrillators were exposed to 60 Co radiation, to 9 MeV electrons and to 6 MV and 10 MV photon radiation. The pacemakers were placed into a water phantom. The following parameters were examined: telemetry, battery, pulse frequency, pulse amplitude, and period at accumulated doses from 2 Gy to 100 Gy. It is concluded that pacemakers in CMOS/Bipolar technology and in 8μ CMOS technology should not be exposed to an absorbed dose exceeding 5 Gy, the latest generation of pacemakers in the 3μm technology will perform satisfactorily up to 70 Gy. (P.A.)

  1. Advanced Pacemaker

    Science.gov (United States)

    1990-01-01

    Synchrony, developed by St. Jude Medical's Cardiac Rhythm Management Division (formerly known as Pacesetter Systems, Inc.) is an advanced state-of-the-art implantable pacemaker that closely matches the natural rhythm of the heart. The companion element of the Synchrony Pacemaker System is the Programmer Analyzer APS-II which allows a doctor to reprogram and fine tune the pacemaker to each user's special requirements without surgery. The two-way communications capability that allows the physician to instruct and query the pacemaker is accomplished by bidirectional telemetry. APS-II features 28 pacing functions and thousands of programming combinations to accommodate diverse lifestyles. Microprocessor unit also records and stores pertinent patient data up to a year.

  2. [Sport for pacemaker patients].

    Science.gov (United States)

    Israel, C W

    2012-06-01

    Sport activity is an important issue in many patients with a pacemaker either because they performed sport activities before pacemaker implantation to reduce the cardiovascular risk or to improve the course of an underlying cardiovascular disease (e.g. coronary artery disease, heart failure) by sports. Compared to patients with an implantable cardioverter defibrillator (ICD) the risks from underlying cardiovascular disease (e.g. ischemia, heart failure), arrhythmia, lead dysfunction or inappropriate therapy are less important or absent. Sport is contraindicated in dyspnea at rest, acute heart failure, new complex arrhythmia, acute myocarditis and acute myocardial infarction, valvular disease with indications for intervention and surgery and comorbidities which prevent physical activity. Patients with underlying cardiovascular disease (including hypertension) should preferably perform types and levels of physical activity that are aerobic (with dynamic exercise) such as running, swimming, cycling instead of sport with high anaerobic demands and high muscular workload. In heart failure, studies demonstrated advantages of isometric sport that increases the amount of muscle, thereby preventing cardiac cachexia. Sport with a risk of blows to the chest or physical contact (e.g. boxing, rugby, martial arts) should be avoided. Implantation, programming and follow-up should respect specific precautions to allow optimal physical activity with a pacemaker including implantation of bipolar leads on the side contralateral to the dominant hand, individual programming of the upper sensor and tracking rate and regular exercise testing.

  3. Programmable Pacemaker

    Science.gov (United States)

    1996-01-01

    Released in 1995, the Trilogy cardiac pacemaker is the fourth generation of a unit developed in the 1970s by NASA, Johns Hopkins Applied Physics Laboratory and St. Jude Medical's Cardiac Rhythm Management Division (formerly known as Pacesetter Systems, Inc.). The new system incorporates the company's PDx diagnostic and programming software and a powerful microprocessor that allows more functions to be fully automatic and gives more detailed information on the patient's health and the performance of the pacing systems. The pacemaker incorporates bidirectional telemetry used for space communications for noninvasive communication with the implanted pacemaker, smaller implantable pulse generators from space microminiaturization, and longer-life batteries from technology for spacecraft electrical power systems.

  4. Trends in Cardiac Pacemaker Batteries

    Directory of Open Access Journals (Sweden)

    Venkateswara Sarma Mallela

    2004-10-01

    Full Text Available Batteries used in Implantable cardiac pacemakers-present unique challenges to their developers and manufacturers in terms of high levels of safety and reliability. In addition, the batteries must have longevity to avoid frequent replacements. Technological advances in leads/electrodes have reduced energy requirements by two orders of magnitude. Micro-electronics advances sharply reduce internal current drain concurrently decreasing size and increasing functionality, reliability, and longevity. It is reported that about 600,000 pacemakers are implanted each year worldwide and the total number of people with various types of implanted pacemaker has already crossed 3 million. A cardiac pacemaker uses half of its battery power for cardiac stimulation and the other half for housekeeping tasks such as monitoring and data logging. The first implanted cardiac pacemaker used nickel-cadmium rechargeable battery, later on zinc-mercury battery was developed and used which lasted for over 2 years. Lithium iodine battery invented and used by Wilson Greatbatch and his team in 1972 made the real impact to implantable cardiac pacemakers. This battery lasts for about 10 years and even today is the power source for many manufacturers of cardiac pacemakers. This paper briefly reviews various developments of battery technologies since the inception of cardiac pacemaker and presents the alternative to lithium iodine battery for the near future.

  5. Pacemaker wires

    International Nuclear Information System (INIS)

    Fransson, S.G.

    1993-01-01

    Evaluation of pacemaker wires were performed by comparing Advanced Multiple Beam Equalization Radiography (AMBER) with conventional chest radiography. The scanning equalization technique of the AMBER unit makes it superior to conventional technique in the depiction of different structures in the mediastinum or in the pleural sinuses. So far motion artifacts have not been considered clinically important. The longer exposure time, however, may impair the assessment of pacemaker wires. The motion artifact described may not only make adequate evaluation impossible but may even give a false impression of a lead fracture. The difference between the two systems was significant. (orig.)

  6. Current use of implantable electrical devices in Sweden: data from the Swedish pacemaker and implantable cardioverter-defibrillator registry.

    Science.gov (United States)

    Gadler, Fredrik; Valzania, Cinzia; Linde, Cecilia

    2015-01-01

    The National Swedish Pacemaker and Implantable Cardioverter-Defibrillator (ICD) Registry collects prospective data on all pacemaker and ICD implants in Sweden. We aimed to report the 2012 findings of the Registry concerning electrical devices implantation rates and changes over time, 1 year complications, long-term device longevity and patient survival. Forty-four Swedish implanting centres continuously contribute implantation of pacemakers and ICDs to the Registry by direct data entry on a specific website. Clinical and technical information on 2012 first implants and postoperative complications were analysed and compared with previous years. Patient survival data were obtained from the Swedish population register database. In 2012, the mean pacemaker and ICD first implantation rates were 697 and 136 per million inhabitants, respectively. The number of cardiac resynchronization therapy (CRT) first implantations/million capita was 41 (CRT pacemakers) and 55 (CRT defibrillators), with only a slight increase in CRT-ICD rate compared with 2011. Most device implantations were performed in men. Complication rates for pacemaker and ICD procedures were 5.3 and 10.1% at 1 year, respectively. Device and lead longevity differed among manufacturers. Pacemaker patients were older at the time of first implant and had generally worse survival rate than ICD patients (63 vs. 82% after 5 years). Pacemaker and ICD implantation rates seem to have reached a level phase in Sweden. Implantable cardioverter-defibrillator and CRT implantation rates are very low and do not reflect guideline indications. Gender differences in CRT and ICD implantations are pronounced. Device and patient survival rates are variable, and should be considered when deciding device type. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  7. A current-controlled PWM bipolar power supply for a magnet load

    International Nuclear Information System (INIS)

    Kang, Y.G.; McGhee, D.G.

    1994-01-01

    The Advanced Photon Source, at Argonne National Laboratory will produce the world's brightest x-ray beams when it is complete. A number of correction magnets are used to maintain proper beam position. Basically, two different types of bipolar power supplies are used for all the correction magnets: one requires dc correction only, and the other requires dc and ac correction. Normally linear-mode power amplifiers would be used for the bipolar power supplies. However, linear-mode power amplifiers dissipate a substantial amount of power as heat, resulting in poor efficiency for their large size. In addition, most commercial bipolar power supplies are linear-mode and available for lower power levels. Therefore, for higher power levels it was necessary to design a bipolar power supply that uses switch-mode power conversion. This paper describes a control technique for a pulse-width-modulatcd bipolar power supply, which can deliver a controlled current, dc plus ac to a correction magnet. A design example of a 150A bipolar power supply is presented

  8. Small functional If current in sinoatrial pacemaker cells of the brown trout (Salmo trutta fario) heart despite strong expression of HCN channel transcripts.

    Science.gov (United States)

    Hassinen, Minna; Haverinen, Jaakko; Vornanen, Matti

    2017-12-01

    Funny current ( I f ), formed by hyperpolarization-activated cyclic nucleotide-gated channels (HCN channels), is supposed to be crucial for the membrane clock regulating the cardiac pacemaker mechanism. We examined the presence and activity of HCN channels in the brown trout ( Salmo trutta fario ) sinoatrial (SA) pacemaker cells and their putative role in heart rate ( f H ) regulation. Six HCN transcripts (HCN1, HCN2a, HCN2ba, HCN2bb, HCN3, and HCN4) were expressed in the brown trout heart. The total HCN transcript abundance was 4.0 and 4.9 times higher in SA pacemaker tissue than in atrium and ventricle, respectively. In the SA pacemaker, HCN3 and HCN4 were the main isoforms representing 35.8 ± 2.7 and 25.0 ± 1.5%, respectively, of the total HCN transcripts. Only a small I f with a mean current density of -1.2 ± 0.37 pA/pF at -140 mV was found in 4 pacemaker cells out of 16 spontaneously beating cells examined, despite the optimization of recording conditions for I f activity. I f was not found in any of the 24 atrial myocytes and 21 ventricular myocytes examined. HCN4 coexpressed with the MinK-related peptide 1 (MiRP1) β-subunit in CHO cells generated large I f currents. In contrast, HCN3 (+MiRP1) failed to produce I f in the same expression system. Cs + (2 mM), which blocked 84 ± 12% of the native I f , reversibly reduced f H 19.2 ± 3.6% of the excised multicellular pacemaker tissue from 53 ± 5 to 44 ± 5 beats/min ( P brown trout heart is largely independent on I f . Copyright © 2017 the American Physiological Society.

  9. Inward rectifier potassium current IKir promotes intrinsic pacemaker activity of thalamocortical neurons.

    Science.gov (United States)

    Amarillo, Yimy; Tissone, Angela I; Mato, Germán; Nadal, Marcela S

    2018-06-01

    Slow repetitive burst firing by hyperpolarized thalamocortical (TC) neurons correlates with global slow rhythms (rectifier potassium current I Kir induces repetitive burst firing at slow and delta frequency bands. We demonstrate this in mouse TC neurons in brain slices by manipulating the Kir maximum conductance with dynamic clamp. We also performed a thorough theoretical analysis that explains how the unique properties of I Kir enable this current to induce slow periodic bursting in TC neurons. We describe a new ionic mechanism based on the voltage- and time-dependent interaction of I Kir and hyperpolarization-activated cationic current I h that endows TC neurons with the ability to oscillate spontaneously at very low frequencies, even below 0.5 Hz. Bifurcation analysis of conductance-based models of increasing complexity demonstrates that I Kir induces bistability of the membrane potential at the same time that it induces sustained oscillations in combination with I h and increases the robustness of low threshold-activated calcium current I T -mediated oscillations. NEW & NOTEWORTHY The strong inwardly rectifying potassium current I Kir of thalamocortical neurons displays a region of negative slope conductance in the current-voltage relationship that generates potassium currents activated by hyperpolarization. Bifurcation analysis shows that I Kir induces bistability of the membrane potential; generates sustained subthreshold oscillations by interacting with the hyperpolarization-activated cationic current I h ; and increases the robustness of oscillations mediated by the low threshold-activated calcium current I T . Upregulation of I Kir in thalamocortical neurons induces repetitive burst firing at slow and delta frequency bands (<4 Hz).

  10. Subclavian Vein Stenosis/Occlusion Following Transvenous Cardiac Pacemaker and Defibrillator Implantation: Incidence, Pathophysiology and Current Management

    Directory of Open Access Journals (Sweden)

    Brian O'Leary

    2015-08-01

    Full Text Available Subclavian vein stenosis is a common, but usually asymptomatic, complication following cardiac device placement. In addition to reviewing the literature on incidence, pathogenesis and management options for this important clinical problem, we describe two cases of symptomatic subclavian vein occlusion following pacemaker/defibrillator placement and successful treatment with venoplasty and stenting.

  11. Electrophysiological heterogeneity of pacemaker cells in the rabbit intercaval region, including the SA node: insights from recording multiple ion currents in each cell.

    Science.gov (United States)

    Monfredi, Oliver; Tsutsui, Kenta; Ziman, Bruce; Stern, Michael D; Lakatta, Edward G; Maltsev, Victor A

    2018-03-01

    Cardiac pacemaker cells, including cells of the sinoatrial node, are heterogeneous in size, morphology, and electrophysiological characteristics. The exact extent to which these cells differ electrophysiologically is unclear yet is critical to understanding their functioning. We examined major ionic currents in individual intercaval pacemaker cells (IPCs) sampled from the paracristal, intercaval region (including the sinoatrial node) that were spontaneously beating after enzymatic isolation from rabbit hearts. The beating rate was measured at baseline and after inhibition of the Ca 2+ pump with cyclopiazonic acid. Thereafter, in each cell, we consecutively measured the density of funny current ( I f ), delayed rectifier K + current ( I K ) (a surrogate of repolarization capacity), and L-type Ca 2+ current ( I Ca,L ) using whole cell patch clamp . The ionic current densities varied to a greater extent than previously appreciated, with some IPCs demonstrating very small or zero I f . The density of none of the currents was correlated with cell size, while I Ca,L and I f densities were related to baseline beating rates. I f density was correlated with I K density but not with that of I Ca,L . Inhibition of Ca 2+ cycling had a greater beating rate slowing effect in IPCs with lower I f densities. Our numerical model simulation indicated that 1) IPCs with small (or zero) I f or small I Ca,L can operate via a major contribution of Ca 2+ clock, 2) I f -Ca 2+ -clock interplay could be important for robust pacemaking function, and 3) coupled I f - I K function could regulate maximum diastolic potential. Thus, we have demonstrated marked electrophysiological heterogeneity of IPCs. This heterogeneity is manifested in basal beating rate and response to interference of Ca 2+ cycling, which is linked to I f . NEW & NOTEWORTHY In the present study, a hitherto unrecognized range of heterogeneity of ion currents in pacemaker cells from the intercaval region is demonstrated

  12. Cognitive and family correlates of current suicidal ideation in children with bipolar disorder.

    Science.gov (United States)

    Weinstein, Sally M; Van Meter, Anna; Katz, Andrea C; Peters, Amy T; West, Amy E

    2015-03-01

    Suicidality among youth with bipolar disorder is an extreme, but largely unaddressed, public health problem. The current study examined the psychosocial characteristics differentiating youth with varying severities of suicidal ideation that may dictate targets for suicide prevention interventions. Participants included 72 youth aged 7-13 (M=9.19, SD=1.61) with DSM-IV-TR bipolar I, II, or NOS and a parent/caregiver. Current suicidal ideation and correlates were assessed at intake, including: demographics and clinical factors (diagnosis, symptom severity, psychiatric comorbidity); child factors (cognitive risk and quality of life); and family factors (parenting stress, family cohesion, and family rigidity). Current ideation was prevalent in this young sample: 41% endorsed any ideation, and 31% endorsed active forms. Depression symptoms, quality of life, hopelessness, self-esteem, and family rigidity differentiated youth with increasing ideation severity. Separate logistic regressions examined all significant child- and family-level factors, controlling for demographic and clinical variables. Greater family rigidity and lower self-esteem remained significant predictors of current planful ideation. Diagnosis, index episode, comorbidity, and mania severity did not differentiate non-ideators from those with current ideation. Limitations include the small sample to examine low base-rate severe ideation, cross-sectional analyses and generalizability of findings beyond the outpatient clinical sample. Findings underscore the importance of assessing and addressing suicidality in preadolescent youth with bipolar disorder, before youth progress to more severe suicidal behaviors. Results also highlight child self-esteem and family rigidity as key treatment targets to reduce suicide risk in pediatric bipolar disorder. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Bipolar programmable current supply for superconducting nuclear magnetic resonance magnets

    Science.gov (United States)

    Koivuniemi, Jaakko; Luusalo, Reeta; Hakonen, Pertti

    1998-09-01

    In high resolution continuous-wave nuclear magnetic resonance (NMR) work well-reproducible, linear sweeps of current are needed. We have developed a microcontroller based programmable current supply, tested with superconducting magnets with inductance of 10 mH and 10 H. We achieved a resolution and noise of 4 ppm. The supply has an internal sweep with programmable ramping rate and a possibility for remote operation from a computer with either GPIB or RS232 interface. It is based on an 18-bit D/A converter. The maximum output current is ±10 A, the sweep rate can be set between 1 μA/s-140 mA/s, and the maximum output voltage is ±2.5 V. In work at ultralow temperatures, especially in superconducting quantum interference device NMR, all rf interference to the experiment should be avoided. One of the sources of this kind of unwanted input is the digital switching noise of fast logic devices. We discuss this problem in the context of our design.

  14. Cardiac pacemaker

    International Nuclear Information System (INIS)

    Kolenik, S.A.

    1976-01-01

    The construction of a cardiac pacemaker is described which is characterized by particularly small dimensions, small weight and long life duration. The weight is under 100g, the specific weight under 1.7. Mass inertia forces which occur through acceleration and retardation processes, thus remain below the threshold values, above which one would have to reckon with considerable damaging of the surrounding body tissue. The maintaining of small size and slight weight is achieved by using an oscillator on COSMOS basis, where by considerably lower energy consumption, amongst others the lifetimes of the batteries used - a lithium anode with thionyl chloride electrolyte - is extended to over 5 years. The reliability can be increased by the use of 2 or more batteries. The designed dimension are 20x60x60 mm 3 . (ORU/LH) [de

  15. Maximizing ion current rectification in a bipolar conical nanopore fluidic diode using optimum junction location.

    Science.gov (United States)

    Singh, Kunwar Pal

    2016-10-12

    The ion current rectification has been obtained as a function of the location of a heterojunction in a bipolar conical nanopore fluidic diode for different parameters to determine the junction location for maximum ion current rectification using numerical simulations. Forward current peaks for a specific location of the junction and reverse current decreases with the junction location due to a change in ion enrichment/depletion in the pore. The optimum location of the heterojunction shifts towards the tip with base/tip diameter and surface charge density, and towards the base with the electrolyte concentration. The optimum location of the heterojunction has been approximated by an equation as a function of pore length, base/tip diameter, surface charge density and electrolyte concentration. The study is useful to design a rectifier with maximum ion current rectification for practical purposes.

  16. Cardiac Pacemakers; Marcapasos Cardiacos

    Energy Technology Data Exchange (ETDEWEB)

    Fiandra, O [Universidad de la Republica, Facultad de Maedicina, Departamento de Cardiologia, Montevideo(Uruguay); Espasandin, W [Universidad de la Republica, Facultad de Medicina, Departamento de Cirugia Cardiaca, Montevideo (Uruguay); Fiandra, H [Instituto Nacional de Cirugia Cardiaca, Departamento de Hemodinamia y Marcapasos, Montevideo (Uruguay); and others

    1984-07-01

    A complete survey of physiological biophysical,clinical and engineering aspects of cardiac facing,including the history and an assessment of possible future developments.Among the topics studied are: pacemakers, energy search, heart stimulating with pacemakers ,mathematical aspects of the electric cardio stimulation chronic, pacemaker implants,proceeding,treatment and control.

  17. Hardware and Software of a Bipolar Current Source Controlled by PC

    Directory of Open Access Journals (Sweden)

    Mirjana Rajčić-Vujasinović

    2008-03-01

    Full Text Available This paper describes a realization of a bipolar current source developed by the paper's authors. The source is intended for use in galvanic and other industrial plants, where a pulse-reverse current supply (with the desired shape in time is required. A prototype of the device, which provides the outcome current intensity up to ± 50 A, has been constructed. The hardware of the source consists of a Pentium IV PC, a commercial ADDA converter, an interface of authors’ original construction as well as a current regulator. The application software is developed using a commercial packet LabView as the basis.

  18. Direct Current Combined With Bipolar Radiofrequency Ablation: An Ex Vivo Feasibility Study

    International Nuclear Information System (INIS)

    Tanaka, Toshihiro; Penzkofer, Tobias; Isfort, Peter; Bruners, Philipp; Disselhorst-Klug, Catherine; Junker, Elmar; Kichikawa, Kimihiko; Schmitz-Rode, Thomas; Mahnken, Andreas H.

    2011-01-01

    The combination of radiofrequency ablation (RFA) with direct current (DC) is a promising strategy to improve the efficiency of RFA. However, DC-enhanced monopolar RFA is limited by electrolytic injury at the positive-electrode site. The aim of this study was to investigate the feasibility of the DC-enhanced bipolar RFA. To obviate the need for the subcutaneous positive electrode, the DC circuit was combined with a commercially available bipolar RFA system, in which both poles of the DC circuit are connected to a single RF probe. DC was applied for 15 min and followed by RFA in bovine livers using the following various DC currents: (1) no DC (control), (2) 3V continued until the end of RFA, (3) 5V continued until the end of RFA, (4) 10V continued until the end of RFA, (5) 5V continued in the circuit with reversed pole, (6) 3V stopped after initiation of RFA, and (7) 5V stopped. Coagulation volume, temperatures at a distance of 5, 10, and 15 mm from the RF probe, mean amperage, ablation duration, applied energy, minimum impedance, and degree of tissue charring were assessed and compared (analysis of variance, Student–Newman–Keuls test). All combined DC and RFA groups did increase coagulation volume. The 10V continued group showed significantly lower applied energy, shortest ablation duration, highest minimum impedance, and highest degree of charring with the lowest coagulation volume (p < 0.05). DC-enhanced bipolar RFA with both poles of the DC circuit on a single probe appears to be ineffective.

  19. Leadless Pacemakers: State of the Art and Future Perspectives.

    Science.gov (United States)

    Della Rocca, Domenico G; Gianni, Carola; Di Biase, Luigi; Natale, Andrea; Al-Ahmad, Amin

    2018-03-01

    Leadless pacemaker therapy is a new technology that aims at avoiding lead- and pocket-related complications of conventional transvenous and epicardial pacing. To date, 2 self-contained leadless pacemakers for right ventricular pacing have been clinically available: the Nanostim Leadless Pacemaker System and the Micra Transcatheter Pacing System. Additionally, a new multicomponent leadless pacemaker for endocardial left ventricular pacing has been proposed as an alternative choice for cardiac resynchronization therapy. In this review, we describe the state of the art of leadless pacing and compare the currently available devices with traditional transvenous leadless pacemakers. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Firing Patterns and Transitions in Coupled Neurons Controlled by a Pacemaker

    International Nuclear Information System (INIS)

    Mei-Sheng, Li; Qi-Shao, Lu; Li-Xia, Duan; Qing-Yun, Wang

    2008-01-01

    To reveal the dynamics of neuronal networks with pacemakers, the firing patterns and their transitions are investigated in a ring HR neuronal network with gap junctions under the control of a pacemaker. Compared with the situation without pacemaker, the neurons in the network can exhibit various firing patterns as the external current is applied or the coupling strength of pacemaker varies. The results are beneficial for understanding the complex cooperative behaviour of large neural assemblies with pacemaker control

  1. Bipolar disorder and complementary medicine: current evidence, safety issues, and clinical considerations.

    Science.gov (United States)

    Sarris, Jerome; Lake, James; Hoenders, Rogier

    2011-10-01

    Bipolar disorder (BD) is a debilitating syndrome that is often undiagnosed and undertreated. Population surveys show that persons with BD often self-medicate with complementary and alternative medicine (CAM) or integrative therapies in spite of limited research evidence supporting their use. To date, no review has focused specifically on nonconventional treatments of BD. The study objectives were to present a review of nonconventional (complementary and integrative) interventions examined in clinical trials on BD, and to offer provisional guidelines for the judicious integrative use of CAM in the management of BD. PubMed, CINAHL,(®) Web of Science, and Cochrane Library databases were searched for human clinical trials in English during mid-2010 using Bipolar Disorder and CAM therapy and CAM medicine search terms. Effect sizes (Cohen's d) were also calculated where data were available. Several positive high-quality studies on nutrients in combination with conventional mood stabilizers and antipsychotic medications in BD depression were identified, while branched-chain amino acids and magnesium were effective (small studies) in attenuating mania in BD. In the treatment of bipolar depression, evidence was mixed regarding omega-3, while isolated studies provide provisional support for a multinutrient formula, n-acetylcysteine, and l-tryptophan. In one study, acupuncture was found to have favorable but nonsignificant effects on mania and depression outcomes. Current evidence supports the integrative treatment of BD using combinations of mood stabilizers and select nutrients. Other CAM or integrative modalities used to treat BD have not been adequately explored to date; however, some early findings are promising. Select CAM and integrative interventions add to established conventional treatment of BD and may be considered when formulating a treatment plan. It is hoped that the safety issues and clinical considerations addressed in this article may encourage the practice

  2. Intermittent pacemaker dysfunction caused by digital mobile telephones.

    Science.gov (United States)

    Naegeli, B; Osswald, S; Deola, M; Burkart, F

    1996-05-01

    This study was designed to evaluate possible interactions between digital mobile telephones and implanted pacemakers. Electromagnetic fields may interfere with normal pacemaker function. Development of bipolar sensing leads and modern noise filtering techniques have lessened this problem. However, it remains unclear whether these features also protect from high frequency noise arising from digital cellular phones. In 39 patients with an implanted pacemaker (14 dual-chamber [DDD], 8 atrial-synchronized ventricular-inhibited [VDD(R)] and 17 ventricular-inhibited [VVI(R)] pacemakers), four mobile phones with different levels of power output (2 and 8 W) were tested in the standby, dialing and operating mode. During continuous electrocardiographic monitoring, 672 tests were performed in each mode with the phones positioned over the pulse generator, the atrial and the ventricular electrode tip. The tests were carried out at different sensitivity settings and, where possible, in the unipolar and bipolar pacing modes as well. In 7 (18%) of 39 patients, a reproducible interference was induced during 26 (3.9%) of 672 tests with the operating phones in close proximity (phone and at maximal sensitivity of the pacemakers (maximal vs. nominal sensitivity, 6% vs. 1.8% positive test results, p = 0.009). When the bipolar and unipolar pacing modes were compared in the same patients, ventricular inhibition was induced only in the unipolar mode (12.5% positive test results, p = 0.0003). Digital mobile phones in close proximity to implanted pacemakers may cause intermittent pacemaker dysfunction with inappropriate ventricular tracking and potentially dangerous pacemaker inhibition.

  3. Bipolar Treatment: Are Bipolar I and Bipolar II Treated Differently?

    Science.gov (United States)

    ... The diagnosis and management of bipolar I and bipolar II disorders: Clinical practice update. Mayo Clinic Proceedings. 2017;92:1532. Haynes PL, et al. Social rhythm therapies for mood disorders: An update. Current Psychiatry Reports. ...

  4. The influence of current mood state, number of previous affective episodes and predominant polarity on insight in bipolar disorder.

    Science.gov (United States)

    de Assis da Silva, Rafael; Mograbi, Daniel C; Camelo, Evelyn Vieira Miranda; Peixoto, Ursula; Santana, Cristina Maria Teixeira; Landeira-Fernandez, Jesus; Morris, Robin G; Cheniaux, Elie

    2017-11-01

    Although many studies have explored the effect of current affective episodes on insight into bipolar disorder, the potential interaction between current mood state and previous affective episodes has not been consistently investigated. To explore the influence of dominant polarity, number of previous affective episodes and current affective state on insight in bipolar disorder patients in euthymia or mania. A total of 101 patients with bipolar disorder were recruited for the study, including 58 patients in euthymia (30 with no defined predominant polarity and 28 with manic predominant polarity) and 43 in mania (26 with no defined predominant polarity and 17 with manic predominant polarity). Patients underwent a clinical assessment and insight was evaluated through the Insight Scale for Affective Disorders. Bipolar disorder patients in mania had worse insight than those in euthymia, with no effect of dominant polarity. In addition, positive psychotic symptoms showed a significant effect on insight and its inclusion as a covariate eliminated differences related to mood state. Finally, the number of previous manic or depressive episodes did not correlate with insight level. Mania is a predictor of loss of insight into bipolar disorder. However, it is possible that its contribution is linked to the more frequent presence of psychotic symptoms in this state. Dominant polarity and number/type of previous affective episodes have a limited impact on insight.

  5. Lifetime anxiety disorder and current anxiety symptoms associated with hastened depressive recurrence in bipolar disorder.

    Science.gov (United States)

    Shah, Saloni; Kim, Jane P; Park, Dong Yeon; Kim, Hyun; Yuen, Laura D; Do, Dennis; Dell'Osso, Bernardo; Hooshmand, Farnaz; Miller, Shefali; Wang, Po W; Ketter, Terence A

    2017-09-01

    To assess differential relationships between lifetime anxiety disorder/current anxiety symptoms and longitudinal depressive severity in bipolar disorder (BD). Stanford BD Clinic outpatients enrolled during 2000-2011 were assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation and followed with the STEP-BD Clinical Monitoring Form while receiving naturalistic treatment for up to two years. Baseline unfavorable illness characteristics/current mood symptoms and times to depressive recurrence/recovery were compared in patients with versus without lifetime anxiety disorder/current anxiety symptoms. Among 105 currently recovered patients, lifetime anxiety disorder was significantly associated with 10/27 (37.0%) demographic/other unfavorable illness characteristics/current mood symptoms/current psychotropics, hastened depressive recurrence (driven by earlier onset age), and a significantly (> two-fold) higher Kaplan-Meier estimated depressive recurrence rate, whereas current anxiety symptoms were significantly associated with 10/27 (37.0%) demographic/other unfavorable illness characteristics/current mood symptoms/current psychotropics and hastened depressive recurrence (driven by lifetime anxiety disorder), but only a numerically higher Kaplan-Meier estimated depressive recurrence rate. In contrast, among 153 currently depressed patients, lifetime anxiety disorder/current anxiety symptoms were not significantly associated with time to depressive recovery or depressive recovery rate. American tertiary BD clinic referral sample, open naturalistic treatment. Research is needed regarding differential relationships between lifetime anxiety disorder and current anxiety symptoms and hastened/delayed depressive recurrence/recovery - specifically whether lifetime anxiety disorder versus current anxiety symptoms has marginally more robust association with hastened depressive recurrence, and whether both have marginally more robust

  6. Do current national and international guidelines have specific recommendations for older adults with bipolar disorder?

    DEFF Research Database (Denmark)

    Dols, Annemiek; Kessing, Lars Vedel; Strejilevich, Sergio A

    2016-01-01

    a variety of sources have become available in recent years. It is expected that at least some of this emerging information on OABD would be incorporated into treatment guidelines available to clinicians around the world. METHODS: The International Society of Bipolar Disorders OABD task force compiled...... and compared recommendations from current national and international guidelines that specifically address geriatric or older individuals with BD (from year 2005 onwards). RESULTS: There were 34 guidelines, representing six continents and 19 countries. The majority of guidelines had no separate section on OABD....... General principles for treating OABD with medication are recommended to be similar to those for younger adults, with special caution for side effects due to somatic comorbidity and concomitant medications. Therapeutic lithium serum levels are suggested to be lower but recommendations are very general...

  7. Measurements of monopolar and bipolar current spreads using forward-masking with a fixed probe.

    Science.gov (United States)

    Bingabr, Mohamed G; Espinoza-Varas, Blas; Sigdel, Saroj

    2014-05-01

    This research employed a forward-masking paradigm to estimate the current spread of monopolar (MP) and bipolar (BP) maskers, with current amplitudes adjusted to elicit the same loudness. Since the spatial separation between active and return electrodes is smaller in BP than in MP configurations, the BP current spread is more localized and presumably superior in terms of speech intelligibility. Because matching the loudness requires higher current in BP than in MP stimulation, previous forward-masking studies show that BP current spread is not consistently narrower across subjects or electrodes within a subject. The present forward-masking measures of current spread differ from those of previous studies by using the same BP probe electrode configuration for both MP and BP masker configurations, and adjusting the current levels of the MP and BP maskers so as to match them in loudness. With this method, the estimate of masker current spread would not be contaminated by differences in probe current spread. Forward masking was studied in four cochlear implant patients, two females and two males, with speech recognition scores higher than 50%; that is, their auditory-nerve survival status was more than adequate to carry out the experiments. The data showed that MP and BP masker configurations produce equivalent masking patterns (and current spreads) in three participants. A fourth participant displayed asymmetrical patterns with enhancement rather than masking in some cases, especially when the probe and masker were at the same location. This study showed equivalent masking patterns for MP and BP maskers when the BP masker current amplitude was increased to match the loudness of the MP masker, and the same BP probe configuration is used with both maskers. This finding could help to explain why cochlear implant users often fail to accrue higher speech intelligibility benefit from BP stimulation.

  8. Mathematical Models of Cardiac Pacemaking Function

    Science.gov (United States)

    Li, Pan; Lines, Glenn T.; Maleckar, Mary M.; Tveito, Aslak

    2013-10-01

    Over the past half century, there has been intense and fruitful interaction between experimental and computational investigations of cardiac function. This interaction has, for example, led to deep understanding of cardiac excitation-contraction coupling; how it works, as well as how it fails. However, many lines of inquiry remain unresolved, among them the initiation of each heartbeat. The sinoatrial node, a cluster of specialized pacemaking cells in the right atrium of the heart, spontaneously generates an electro-chemical wave that spreads through the atria and through the cardiac conduction system to the ventricles, initiating the contraction of cardiac muscle essential for pumping blood to the body. Despite the fundamental importance of this primary pacemaker, this process is still not fully understood, and ionic mechanisms underlying cardiac pacemaking function are currently under heated debate. Several mathematical models of sinoatrial node cell membrane electrophysiology have been constructed as based on different experimental data sets and hypotheses. As could be expected, these differing models offer diverse predictions about cardiac pacemaking activities. This paper aims to present the current state of debate over the origins of the pacemaking function of the sinoatrial node. Here, we will specifically review the state-of-the-art of cardiac pacemaker modeling, with a special emphasis on current discrepancies, limitations, and future challenges.

  9. Mathematical Models of Cardiac Pacemaking Function

    Directory of Open Access Journals (Sweden)

    Pan eLi

    2013-10-01

    Full Text Available Over the past half century, there has been intense and fruitful interaction between experimental and computational investigations of cardiac function. This interaction has, for example, led to deep understanding of cardiac excitation-contraction coupling; how it works, as well as how it fails. However, many lines of inquiry remain unresolved, among them the initiation of each heartbeat. The sinoatrial node, a cluster of specialized pacemaking cells in the right atrium of the heart, spontaneously generates an electro-chemical wave that spreads through the atria and through the cardiac conduction system to the ventricles, initiating the contraction of cardiac muscle essential for pumping blood to the body. Despite the fundamental importance of this primary pacemaker, this process is still not fully understood, and ionic mechanisms underlying cardiac pacemaking function are currently under heated debate. Several mathematical models of sinoatrial node cell membrane electrophysiology have been constructed as based on different experimental data sets and hypotheses. As could be expected, these differing models offer diverse predictions about cardiac pacemaking activities. This paper aims to present the current state of debate over the origins of the pacemaking function of the sinoatrial node. Here, we will specifically review the state-of-the-art of cardiac pacemaker modeling, with a special emphasis on current discrepancies, limitations, and future challenges.

  10. A four-diode full-wave ionic current rectifier based on bipolar membranes: overcoming the limit of electrode capacity.

    Science.gov (United States)

    Gabrielsson, Erik O; Janson, Per; Tybrandt, Klas; Simon, Daniel T; Berggren, Magnus

    2014-08-13

    Full-wave rectification of ionic currents is obtained by constructing the typical four-diode bridge out of ion conducting bipolar membranes. Together with conjugated polymer electrodes addressed with alternating current, the bridge allows for generation of a controlled ionic direct current for extended periods of time without the production of toxic species or gas typically arising from electrode side-reactions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. What Is a Pacemaker?

    Science.gov (United States)

    ... your pacemaker. • If you work around industrial microwaves, electricity, cars or other large motors, ask your doctor about possible effects. Can I use a cell phone or microwave oven if I have a pacemaker? Microwave ovens, electric blankets, remote controls for TV and other common ...

  12. Effect of germanium concentrations on tunnelling current calculation of Si/Si1-xGex/Si heterojunction bipolar transistor

    Science.gov (United States)

    Hasanah, L.; Suhendi, E.; Khairrurijal

    2018-05-01

    Tunelling current calculation on Si/Si1-xGex/Si heterojunction bipolar transistor was carried out by including the coupling between transversal and longitudinal components of electron motion. The calculation results indicated that the coupling between kinetic energy in parallel and perpendicular to S1-xGex barrier surface affected tunneling current significantly when electron velocity was faster than 1x105 m/s. This analytical tunneling current model was then used to study how the germanium concentration in base to Si/Si1-xGex/Si heterojunction bipolar transistor influenced the tunneling current. It is obtained that tunneling current increased as the germanium concentration given in base decreased.

  13. [Analysis of pacemaker ECGs].

    Science.gov (United States)

    Israel, Carsten W; Ekosso-Ejangue, Lucy; Sheta, Mohamed-Karim

    2015-09-01

    The key to a successful analysis of a pacemaker electrocardiogram (ECG) is the application of the systematic approach used for any other ECG without a pacemaker: analysis of (1) basic rhythm and rate, (2) QRS axis, (3) PQ, QRS and QT intervals, (4) morphology of P waves, QRS, ST segments and T(U) waves and (5) the presence of arrhythmias. If only the most obvious abnormality of a pacemaker ECG is considered, wrong conclusions can easily be drawn. If a systematic approach is skipped it may be overlooked that e.g. atrial pacing is ineffective, the left ventricle is paced instead of the right ventricle, pacing competes with intrinsic conduction or that the atrioventricular (AV) conduction time is programmed too long. Apart from this analysis, a pacemaker ECG which is not clear should be checked for the presence of arrhythmias (e.g. atrial fibrillation, atrial flutter, junctional escape rhythm and endless loop tachycardia), pacemaker malfunction (e.g. atrial or ventricular undersensing or oversensing, atrial or ventricular loss of capture) and activity of specific pacing algorithms, such as automatic mode switching, rate adaptation, AV delay modifying algorithms, reaction to premature ventricular contractions (PVC), safety window pacing, hysteresis and noise mode. A systematic analysis of the pacemaker ECG almost always allows a probable diagnosis of arrhythmias and malfunctions to be made, which can be confirmed by pacemaker control and can often be corrected at the touch of the right button to the patient's benefit.

  14. Mixed states in bipolar disorder - changes in DSM-5 and current treatment recommendations.

    Science.gov (United States)

    Betzler, Felix; Stöver, Laura Apollonia; Sterzer, Philipp; Köhler, Stephan

    2017-11-01

    Mixed states in affective disorders represent a particular challenge in clinical routine, characterized by a complicated course of treatment and a worse treatment response. Clinical features of mixed states and the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria are presented and critical discussed. We then performed a systematic review using the terms 'bipolar', 'mixed' and 'randomized' to evaluate current treatment options. For pharmacological treatment of mixed states in total, there is still insufficient data from RCTs. However, there is some evidence for efficacy in mixed states from RCTs for atypical antipsychotics, especially olanzapine, aripiprazole and asenapine as well as mood stabilizers as valproate and carbamazepine. Mixed states are of a high clinical relevance and the DSM-5 criteria substantially reduced the diagnostic threshold. Besides advantages of a better characterization of patients with former DSM-IV-defined mixed episodes, disadvantages arise for example differential diagnoses with a substantial overlap in symptoms such as borderline personality disorders. Atypical antipsychotics, valproate and carbamazepine demonstrated efficacy in a limited sample of RCTs. The number of RCTs in the treatment of mixed states is highly limited. Furthermore, nearly all studies were funded by pharmaceutical companies which may lead to an underestimation of classical mood stabilizers such as lithium.

  15. Selective interference with pacemaker activity by electrical dental devices.

    Science.gov (United States)

    Miller, C S; Leonelli, F M; Latham, E

    1998-01-01

    We sought to determine whether electromagnetic interference with cardiac pacemakers occurs during the operation of contemporary electrical dental equipment. Fourteen electrical dental devices were tested in vitro for their ability to interfere with the function of two Medtronics cardiac pacemakers (one a dual-chamber, bipolar Thera 7942 pacemaker, the other a single-chamber, unipolar Minix 8340 pacemaker). Atrial and ventricular pacemaker output and electrocardiographic activity were monitored by means of telemetry with the use of a Medtronics 9760/90 programmer. Atrial and ventricular pacing were inhibited by electromagnetic interference produced by the electrosurgical unit up to a distance of 10 cm, by the ultrasonic bath cleaner up to 30 cm, and by the magnetorestrictive ultrasonic scalers up to 37.5 cm. In contrast, operation of the amalgamator, electric pulp tester, composite curing light, dental handpieces, electric toothbrush, microwave oven, dental chair and light, ENAC ultrasonic instrument, radiography unit, and sonic scaler did not alter pacing rate or rhythm. These results suggest that certain electrosurgical and ultrasonic instruments may produce deleterious effects in medically fragile patients with cardiac pacemakers.

  16. Empirically supported psychosocial interventions for bipolar disorder: Current state of the research.

    Science.gov (United States)

    Salcedo, Stephanie; Gold, Alexandra K; Sheikh, Sana; Marcus, Peter H; Nierenberg, Andrew A; Deckersbach, Thilo; Sylvia, Louisa G

    2016-09-01

    Bipolar disorder requires psychiatric medications, but even guideline-concordant treatment fails to bring many patients to remission or keep them euthymic. To address this gap, researchers have developed adjunctive psychotherapies. The purpose of this paper is to critically review the evidence for the efficacy of manualized psychosocial interventions for bipolar disorder. We conducted a search of the literature to examine recent (2007-present), randomized controlled studies of the following psychotherapy interventions for bipolar disorder: psychoeducation (PE), cognitive behavioral therapy (CBT), interpersonal and social rhythm therapy (IPSRT), dialectical behavior therapy (DBT), mindfulness-based cognitive therapy (MBCT), and family therapies such as family focused therapy (FFT). All of the psychotherapy interventions appear to be effective in reducing depressive symptoms. Psychoeducation and CBT are associated with increased time to mood episode relapse or recurrence. MBCT has demonstrated a particular effectiveness in improving depressive and anxiety symptoms. Online psychotherapy interventions, programs combining one or more psychotherapy interventions, and targeted interventions centering on particular symptoms have been the focus of recent, randomized controlled studies in bipolar disorder. Psychotherapy interventions for the treatment of bipolar disorder have substantial evidence for efficacy. The next challenge will to disseminate these psychotherapies into the community. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Final generic environmental statement on the routine use of plutonium-powered cardiac pacemakers. Update of information on power sources for pacemakers

    International Nuclear Information System (INIS)

    1979-05-01

    The Final Environmental Statement on Routine Use of Plutonium-Powered Cardiac Pacemakers (FES) was issued in July 1976. Supplement 1, prepared in 1978, updates the FES with respect to power sources for pacemakers. Particular attention is given to the non-nuclear lithium batteries as alternatives to 238-Pu power sources in pacemakers. Supplement 1 also considers the current extent of pacemaker use and makeup of the patient population and concludes that the FES' conclusion is still valid that distribution of 238-Pu powered pacemakers for routine use should be authorized subject to specific conditions

  18. Cytokines in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Vinberg, Maj; Vedel Kessing, Lars

    2012-01-01

    BACKGROUND: Current research and hypothesis regarding the pathophysiology of bipolar disorder suggests the involvement of immune system dysfunction that is possibly related to disease activity. Our objective was to systematically review evidence of cytokine alterations in bipolar disorder according...... to affective state. METHODS: We conducted a systemtic review of studies measuring endogenous cytokine concentrations in patients with bipolar disorder and a meta-analysis, reporting results according to the PRISMA statement. RESULTS: Thirteen studies were included, comprising 556 bipolar disorder patients...

  19. Transcranial direct-current stimulation (tDCS) for bipolar depression: A systematic review and meta-analysis.

    Science.gov (United States)

    Dondé, Clément; Amad, Ali; Nieto, Isabel; Brunoni, André Russowsky; Neufeld, Nicholas H; Bellivier, Frank; Poulet, Emmanuel; Geoffroy, Pierre-Alexis

    2017-08-01

    Bipolar disorder (BD) is a severe and recurrent brain disorder that can manifest in manic or depressive episodes. Transcranial Direct Current Stimulation (tDCS) has been proposed as a novel therapeutic modality for patients experiencing bipolar depression, for which standard treatments are often inefficient. While several studies have been conducted in this patient group, there has been no systematic review or meta-analysis that specifically examines bipolar depression. We aimed to address this gap in the literature and evaluated the efficacy and tolerability of tDCS in patients fulfilling DSM-IV-TR criteria for BD I, II, or BD not otherwise specified (NOS). We systematically searched the literature from April 2002 to November 2016 to identify relevant publications for inclusion in our systematic review and meta-analysis. Effect sizes for depression rating-scale scores were expressed as the standardized mean difference (SMD) before and after tDCS. Thirteen of 382 identified studies met eligibility criteria for our systematic review. The meta-analysis included 46 patients from 7 studies with depression rating-scale scores pre- and post-tDCS. Parameters of tDCS procedures were heterogeneous. Depression scores decreased significantly with a medium effect size after acute-phase of treatment (SMD 0.71 [0.25-1.18], z=3.00, p=0.003) and at the furthest endpoint (SMD 1.27 [0.57-1.97], z=3.57, p=0.0004). Six cases of affective switching under tDCS treatment protocols were observed. Depressive symptoms respond to tDCS in patients with BD. Additional studies, and particularly randomized controlled trials, are needed to clarify the effectiveness of tDCS in bipolar depression, the frequency of tDCS-emergent hypomania/mania, and which tDCS modalities are most efficient. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Radiation effect on implanted pacemakers

    International Nuclear Information System (INIS)

    Pourhamidi, A.H.

    1983-01-01

    It was previously thought that diagnostic or therapeutic ionizing radiation did not have an adverse effect on the function of cardiac pacemakers. Recently, however, some authors have reported damaging effect of therapeutic radiation on cardiac pulse generators. An analysis of a recently-extracted pacemaker documented the effect of radiation on the pacemaker pulse generator

  1. The clinical trajectory of emerging bipolar disorder among the high-risk offspring of bipolar parents: current understanding and future considerations.

    Science.gov (United States)

    Duffy, A; Vandeleur, C; Heffer, N; Preisig, M

    2017-11-22

    Relatively little is known about the onset of bipolar disorder, yet the early illness course is already associated with significant morbidity and mortality. Therefore, characterizing the bipolar illness trajectory is key to risk prediction and early intervention advancement. In this narrative review, we discuss key findings from prospective longitudinal studies of the high-risk offspring of bipolar parents and related meta-analyses that inform us about the clinical trajectory of emerging bipolar disorder. Challenges such as phenotypic and etiologic heterogeneity and the non-specificity of early symptoms and syndromes are highlighted. Implications of the findings for both research and clinical practice are discussed. Bipolar disorder in young people at familial risk does not typically onset with a hypomanic or manic episode. Rather the first activated episode is often preceded by years of impairing psychopathological states that vary over development and across emerging bipolar subtype. Taking heterogeneity into account and adopting a more comprehensive approach to diagnosis seems necessary to advance earlier identification and our understanding of the onset of bipolar disorder.

  2. Waiting for a pacemaker

    DEFF Research Database (Denmark)

    Risgaard, Bjarke; Elming, Hanne; Jensen, Gunnar

    2012-01-01

    AIMS: To determine waiting period-related morbidity, mortality, and adverse events in acute patients waiting for a permanent pacemaker (PPM).METHODS AND RESULTS: A retrospective chart review of all PPM implantations in Region Zealand, Denmark, in 2009 was conducted. Patients were excluded...... at least one adverse event during the waiting period. The present study indicates that a waiting period is dangerous as it is associated with an increased risk of adverse events. Acute PPMs should be implanted with a 24-h pacemaker implantation service capacity....

  3. Attentional biases for emotional facial stimuli in currently depressed patients with bipolar disorder

    Directory of Open Access Journals (Sweden)

    Lemke Leyman

    2009-01-01

    Full Text Available En comparación con las numerosas investigaciones centradas en los factores de vulnerabilidad cognitiva que subyacen en el inicio y el desarrollo del trastorno depresivo mayor, los estudios que investigan el procesamiento disfuncional de la información emocional en el trastorno bipolar siguen siendo escasos. Por ello, el presente estudio experimental ha analizado la naturaleza y el curso temporal de los sesgos atencionales en pacientes depresivos con trastorno bipolar. Un total de catorce pacientes deprimidos con Trastorno Bipolar I (TB y catorce participantes controles no deprimidos (CN, emparejados en edad, sexo y nivel educativo, realizaron una modificación emocional de la tarea de señalización espacial. Las señales consistían en expresiones faciales de enfado, neutrales y positivas presentadas durante 200 y 1.000 ms. Los pacientes con TB mostraron un mayor efecto de validación de las señales en las caras de enfado y presentaron más dificultades a la hora de desvincular la atención de las expresiones faciales de enfado y de alegría en comparación con los participantes CN, que por el contrario, demostraron un «sesgo protector» distanciado de la información negativa. Este patrón diferenciado de procesamiento atencional solo se halló en la fase inicial del procesamiento de la información en una presentación de 200 ms de duración. Estos resultados demuestran la existencia de déficits en las fases iniciales del procesamiento atencional de la información emocional en pacientes deprimidos bipolares en comparación con los controles sanos.

  4. Distinguishing between Unipolar Depression and Bipolar Depression: Current and Future Clinical and Neuroimaging Perspectives

    OpenAIRE

    de Almeida, Jorge Renner Cardoso; Phillips, Mary Louise

    2012-01-01

    Differentiating bipolar disorder (BD) from recurrent unipolar depression (UD) is a major clinical challenge. Main reasons for this include the higher prevalence of depressive relative to hypo/manic symptoms during the course of BD illness and the high prevalence of subthreshold manic symptoms in both BD and UD depression. Identifying objective markers of BD might help improve accuracy in differentiating between BD and UD depression, to ultimately optimize clinical and functional outcome for a...

  5. Sub-bandgap photonic base current method for characterization of interface states at heterointerfaces in heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Shin, H. T.; Kim, K. H.; Kim, K. S.

    2004-01-01

    In this paper, we propose a novel photonic base current analysis method to characterize the interface states in heterojunction bipolar transistors (HBTs) by using the photonic I-V characteristics under sub-bandgap photonic excitation. For the photonic current-voltage characterization of HBTs, an optical source with a photon energy less than the bandgap energy of Al 0.3 Ga 0.7 As and GaAs (E ph = 0.95 eV g,AlGaAs = 1.79 eV, E g,GaAs = 1.45 eV) is employed for the characterization of the interface states distributed in the photo-responsive energy band (E C - 0.95 ≤ E it ≤ E C ) in emitter-base heterojunction at HBTs. The proposed novel method, which is applied to bipolar junction transistors for the first time, is simple, and an accurate analysis of interface traps in HBTs is possible. By using the photonic base-current and the dark-base-current, we qualitatively analyze the interface trap at the Al 0.3 Ga 0.7 As/GaAs heterojunction interface in HBTs.

  6. Current density and catalyst-coated membrane resistance distribution of hydro-formed metallic bipolar plate fuel cell short stack with 250 cm2 active area

    Science.gov (United States)

    Haase, S.; Moser, M.; Hirschfeld, J. A.; Jozwiak, K.

    2016-01-01

    An automotive fuel cell with an active area of 250 cm2 is investigated in a 4-cell short stack with a current and temperature distribution device next to the bipolar plate with 560 current and 140 temperature segments. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this current scan shunt module. The applied fuel cell consists of bipolar plates constructed of 75-μm-thick, welded stainless-steel foils and a graphitic coating. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this module with a 6% deviation in in-plane conductivity. The current density distribution is evaluated up to 2.4 A cm-2. The entire cell's investigated volumetric power density is 4.7 kW l-1, and its gravimetric power density is 4.3 kW kg-1 at an average cell voltage of 0.5 V. The current density distribution is determined without influencing the operating cell. In addition, the current density distribution in the catalyst-coated membrane and its effective resistivity distribution with a finite volume discretisation of Ohm's law are evaluated. The deviation between the current density distributions in the catalyst-coated membrane and the bipolar plate is determined.

  7. Atrioventricular Pacemaker Lead Reversal

    Directory of Open Access Journals (Sweden)

    Mehmet K Aktas, MD

    2007-01-01

    Full Text Available During cardiac surgery temporary epicardial atrial and ventricular leads are placed in case cardiac pacing is required postoperatively. We present the first reported series of patients with reversal of atrioventricular electrodes in the temporary pacemaker without any consequent deleterious hemodynamic effect. We review the electrocardiographic findings and discuss the findings that lead to the discovery of atrioventricular lead reversal.

  8. Evolução do conceito e controvérsias atuais sobre o transtorno bipolar do humor Bipolar disorder: evolution of the concept and current controversies

    Directory of Open Access Journals (Sweden)

    José Alberto Del Porto

    2004-10-01

    Full Text Available O autor revê o conceito de transtorno bipolar como um processo em evolução. Suas raízes podem ser encontradas no trabalho de Araeteus da Capadócia, que assumia serem a melancolia e a mania duas formas da mesma doença. A compreensão atual da doença bipolar começou na França, através dos trabalhos de Falret (1851 e Baillarguer (1854. Os conceitos fundamentais de Kraepelin mudaram as bases da nosologia psiquiátrica, e o conceito unitário de Kraepelin sobre a insanidade maníaco-depressiva passou a ser amplamente aceito. Depois de Kraepelin, no entanto, as idéias de Kleist e Leonhard, na Alemanha, e o trabalho subseqüente de Angst, Perris e Winokur enfatizaram a distinção entre as formas monopolares e bipolares da depressão. Mais recentemente a ênfase mudou novamente para o espectro bipolar, que em suas formas leves expande-se às bordas dos temperamentos normais. Finalizando, o autor sumariza os aspectos polêmicos da nosologia da doença bipolar e seus limites com as esquizofrenias, a doença esquizoafetiva e as psicoses ciclóides.The author reviews the evolution of the concept of bipolar disorder as an ongoing process. Its roots can be found in the work of Araeteus of Capadocia, who assumed that melancholia and mania were two forms of the same disease. The modern understanding of bipolar disorder began in France, through the work of Falret (1851 and Baillarger (1854. The pivotal concepts of Emil Kraepelin changed the basis of psychiatric nosology, and Kraepelin's unitary concept of manic-depressive insanity was largely accepted. Kraepelin and Weigandt's ideas on mixed states were the cornerstone of this unitary concept. After Kraepelin, however, the ideas of Kleist and Leonhard, in Germany, as well as the work of Angst, Perris and Winokur, emphasized the distinction between unipolar and bipolar forms of depression. More recently, the emphasis has shifted again to the bipolar spectrum, which, in its mild forms, expanded to the

  9. Improving Treatment Adherence in Bipolar Disorder: A Review of Current Psychosocial Treatment Efficacy and Recommendations for Future Treatment Development

    Science.gov (United States)

    Gaudiano, Brandon A.; Weinstock, Lauren M.; Miller, Ivan W.

    2008-01-01

    Treatment adherence is a frequent problem in bipolar disorder, with research showing that more than 60% of bipolar patients are at least partially nonadherent to medications. Treatment nonadherence is consistently predictive of a number of negative outcomes in bipolar samples, and the discontinuation of mood stabilizers places these patients at…

  10. Do current national and international guidelines have specific recommendations for older adults with bipolar disorder? A brief report.

    Science.gov (United States)

    Dols, Annemiek; Kessing, Lars Vedel; Strejilevich, Sergio A; Rej, Soham; Tsai, Shang-Ying; Gildengers, Ariel G; Almeida, Osvaldo P; Shulman, Kenneth I; Sajatovic, Martha

    2016-12-01

    Older adults with bipolar disorder (OABD) are a growing segment of patients with bipolar disorder (BD) for which specific guidelines are warranted. Although, OABD are frequently excluded from randomized controlled trials due to their age or somatic comorbidity, more treatment data from a variety of sources have become available in recent years. It is expected that at least some of this emerging information on OABD would be incorporated into treatment guidelines available to clinicians around the world. The International Society of Bipolar Disorders OABD task force compiled and compared recommendations from current national and international guidelines that specifically address geriatric or older individuals with BD (from year 2005 onwards). There were 34 guidelines, representing six continents and 19 countries. The majority of guidelines had no separate section on OABD. General principles for treating OABD with medication are recommended to be similar to those for younger adults, with special caution for side effects due to somatic comorbidity and concomitant medications. Therapeutic lithium serum levels are suggested to be lower but recommendations are very general and mostly not informed by specific research evidence. There is a lack of emphasis of OABD-specific issues in existing guidelines. Given the substantial clinical heterogeneity in BD across the life span, along with the rapidly expanding population of older individuals worldwide, and limited mental health workforce with geriatric expertise, it is critical that additional effort and resources be devoted to studying treatment interventions specific to OABD and that treatment guidelines reflect research findings. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Protection of pacemaker wearers: effects on magnetic fields on the operation of implanted cardiac pacemakers

    International Nuclear Information System (INIS)

    Souques, M.; Lambrozo, J.; Frank, R.; Himbert, C.

    2002-01-01

    The aim of this study was to assess the changes in the behavior of cardiac pacemakers exposed to 50 and 60 Hz magnetic fields generated by industrial current and 20 to 50 khz magnetic fields generated by a household in a booming period - the induction cook top - and to study the incidence of these changes in a population of subjects with implanted pacemakers. This will enabled to give patients advices about dealing with electric transport lines and facilities and with induction cook tops and to advise manufacturers about the risks involved

  12. Wide-range bipolar pulse conductance instrument employing current and voltage modes with sampled or integrated signal acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Calhoun, R K; Holler, F J [Kentucky Univ., Lexington, KY (United States). Dept. of Chemistry; Geiger, jr, R F; Nieman, T A [Illinois Univ., Urbana, IL (United States). Dept. of Chemistry; Caserta, K J [Procter and Gamble Co., Cincinnati, OH (United States)

    1991-11-05

    An instrument for measuring solution conductance using the bipolar pulse technique is described. The instrument is capable of measuring conductances in the range of 5x10{sup -9}-10{Omega}{sup -1} with 1% accuracy or better in as little as 32 {mu}s. Accuracy of 0.001-0.01% is achievable over the range 1x10{sup -6}-1{Omega}{sup -1}. Circuitry and software are described that allow the instrument to adjust automatically the pulse height, pulse duration, excitation mode (current or voltage pulse) and data acquisition mode (sampled or integrated) to acquire data of optimum accuracy and precision. The urease-catalyzed decomposition of urea is used to illustrate the versality of the instrument, and other applications are cited. (author). 60 refs.; 7 figs.; 2 tabs.

  13. Metabolic syndrome in subjects with bipolar disorder and major depressive disorder in a current depressive episode: Population-based study: Metabolic syndrome in current depressive episode.

    Science.gov (United States)

    Moreira, Fernanda Pedrotti; Jansen, Karen; Cardoso, Taiane de Azevedo; Mondin, Thaíse Campos; Magalhães, Pedro Vieira da Silva; Kapczinski, Flávio; Souza, Luciano Dias de Mattos; da Silva, Ricardo Azevedo; Oses, Jean Pierre; Wiener, Carolina David

    2017-09-01

    To assess the differences in the prevalence of the metabolic syndrome (MetS) and their components in young adults with bipolar disorder (BD) and major depressive disorder (MDD) in a current depressive episode. This was a cross-sectional study with young adults aged 24-30 years old. Depressive episode (bipolar or unipolar) was assessed using the Mini International Neuropsychiatric Interview - Plus version (MINI Plus). The MetS was assessed using the National Cholesterol Education Program Adult Treatment Panel III (NCEP/ATP III). The sample included 972 subjects with a mean age of 25.81 (±2.17) years. Both BD and MDD patients showed higher prevalence of MetS compared to the population sample (BD = 46.9%, MDD = 35.1%, population = 22.1%, p depressive episode compared to the general population. Moreover, there was a significant difference on BMI values in the case of BD and MDD subjects (p = 0.016). Metabolic components were significantly associated with the presence of depressive symptoms, independently of the diagnosis. Copyright © 2017. Published by Elsevier Ltd.

  14. Pacemaker Use Following Heart Transplantation

    Science.gov (United States)

    Mallidi, Hari R.; Bates, Michael

    2017-01-01

    Background: The incidence of permanent pacemaker implantation after orthotopic heart transplantation has been reported to be 2%-24%. Transplanted hearts usually exhibit sinus rhythm in the operating room following reperfusion, and most patients do not exhibit significant arrhythmias during the postoperative period. However, among the patients who do exhibit abnormalities, pacemakers may be implanted for early sinus node dysfunction but are rarely used after 6 months. Permanent pacing is often required for atrioventricular block. A different cohort of transplant patients presents later with bradycardia requiring pacemaker implantation, reported to occur in approximately 1.5% of patients. The objectives of this study were to investigate the indications for pacemaker implantation, compare the need for pacemakers following bicaval vs biatrial anastomosis, and examine the long-term outcomes of heart transplant patients who received pacemakers. Methods: For this retrospective, case-cohort, single-institution study, patients were identified from clinical research and administrative transplant databases. Information was supplemented with review of the medical records. Standard statistical techniques were used, with chi-square testing for categorical variables and the 2-tailed t test for continuous variables. Survival was compared with the use of log-rank methods. Results: Between January 1968 and February 2008, 1,450 heart transplants were performed at Stanford University. Eighty-four patients (5.8%) were identified as having had a pacemaker implanted. Of these patients, 65.5% (55) had the device implanted within 30 days of transplantation, and 34.5% (29) had late implantation. The mean survival of patients who had an early pacemaker implant was 6.4 years compared to 7.7 years for those with a late pacemaker implant (Ppacemaker implantation. Starting in 1997, a bicaval technique was used for implantation. The incidence of pacemaker implantation by technique was 2.0% for

  15. Measurement of low-frequency base and collector current noise and coherence in SiGe heterojunction bipolar transistors using transimpedance amplifiers

    NARCIS (Netherlands)

    Bruce, S.P.O.; Vandamme, L.K.J.; Rydberg, A.

    1999-01-01

    Transimpedance amplifiers have been used for direct study of current noise in silicon germanium (SiGe) heterojunction bipolar transistors (HBT's) at different biasing conditions. This has facilitated a wider range of resistances in the measurement circuit around the transistor than is possible when

  16. Pharmacological analysis of the activation and receptor properties of the tonic GABA(CR current in retinal bipolar cell terminals.

    Directory of Open Access Journals (Sweden)

    Stefanie M Jones

    Full Text Available GABAergic inhibition in the central nervous system (CNS can occur via rapid, transient postsynaptic currents and via a tonic increase in membrane conductance, mediated by synaptic and extrasynaptic GABA(A receptors (GABA(ARs respectively. Retinal bipolar cells (BCs exhibit a tonic current mediated by GABA(CRs in their axon terminal, in addition to synaptic GABA(AR and GABA(CR currents, which strongly regulate BC output. The tonic GABA(CR current in BC terminals (BCTs is not dependent on vesicular GABA release, but properties such as the alternative source of GABA and the identity of the GABA(CRs remain unknown. Following a recent report that tonic GABA release from cerebellar glial cells is mediated by Bestrophin 1 anion channels, we have investigated their role in non-vesicular GABA release in the retina. Using patch-clamp recordings from BCTs in goldfish retinal slices, we find that the tonic GABA(CR current is not reduced by the anion channel inhibitors NPPB or flufenamic acid but is reduced by DIDS, which decreases the tonic current without directly affecting GABA(CRs. All three drugs also exhibit non-specific effects including inhibition of GABA transporters. GABA(CR ρ subunits can form homomeric and heteromeric receptors that differ in their properties, but BC GABA(CRs are thought to be ρ1-ρ2 heteromers. To investigate whether GABA(CRs mediating tonic and synaptic currents may differ in their subunit composition, as is the case for GABA(ARs, we have examined the effects of two antagonists that show partial ρ subunit selectivity: picrotoxin and cyclothiazide. Tonic and synaptic GABA(CR currents were differentially affected by both drugs, suggesting that a population of homomeric ρ1 receptors contributes to the tonic current. These results extend our understanding of the multiple forms of GABAergic inhibition that exist in the CNS and contribute to visual signal processing in the retina.

  17. Physical and mental health burden in cases of bipolar disorder classified as current, former, or non-tobacco smokers.

    Science.gov (United States)

    Icick, R; Gard, S; Barde, M; Carminati, M; Desage, A; Guillaume, S; Scott, J; Bellivier, F

    2017-01-15

    Tobacco smoking increases the global burden of bipolar disorder (BD). We examined markers of physical and mental health that are associated with tobacco smoking, controlling for confounders that have not always been considered in previous studies of BD. Over 600 individuals with BD I or II referred to the French Network for bipolar disorder (FACE-BD) who completed standardized assessments, and could be reliably classified as current (CS) or former smokers (FS), were compared with those who were never smokers (NS) on: BD symptom load and psychiatric comorbidities; prevalence of alcohol and substance use disorders (ASUD); medication usage; functioning and physical health parameters. The bivariate and multivariate analyses took into account age and gender. 300 cases (49%) were CS, 78 (13%) FS and 238 (39%) had never smoked. Rates were similar across genders regardless of BD subtype. Compared with NS, CS were more likely to have an ASUD (Odds Ratio (OR) 5.18), BD I (OR 2.09), and lower abdominal obesity (OR 0.97), and FS were more likely to have an ASUD (OR 6.32) and higher abdominal obesity (OR 1.03). The sample comprised of white Europeans; the FS subgroup was relatively small and we did not apply any statistical correction for the bivariate analyses. The increased risk of physical and mental health burden in CS and FS compared to NS represents avoidable morbidity in BD. This study offers support to the argument that individuals with BD should be routinely offered support to prevent or stop tobacco smoking. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Distinguishing between unipolar depression and bipolar depression: current and future clinical and neuroimaging perspectives.

    Science.gov (United States)

    Cardoso de Almeida, Jorge Renner; Phillips, Mary Louise

    2013-01-15

    Differentiating bipolar disorder (BD) from recurrent unipolar depression (UD) is a major clinical challenge. Main reasons for this include the higher prevalence of depressive relative to hypo/manic symptoms during the course of BD illness and the high prevalence of subthreshold manic symptoms in both BD and UD depression. Identifying objective markers of BD might help improve accuracy in differentiating between BD and UD depression, to ultimately optimize clinical and functional outcome for all depressed individuals. Yet, only eight neuroimaging studies to date have directly compared UD and BD depressed individuals. Findings from these studies suggest more widespread abnormalities in white matter connectivity and white matter hyperintensities in BD than UD depression, habenula volume reductions in BD but not UD depression, and differential patterns of functional abnormalities in emotion regulation and attentional control neural circuitry in the two depression types. These findings suggest different pathophysiologic processes, especially in emotion regulation, reward, and attentional control neural circuitry in BD versus UD depression. This review thereby serves as a call to action to highlight the pressing need for more neuroimaging studies, using larger samples sizes, comparing BD and UD depressed individuals. These future studies should also include dimensional approaches, studies of at-risk individuals, and more novel neuroimaging approaches, such as connectivity analysis and machine learning. Ultimately, these approaches might provide biomarkers to identify individuals at future risk for BD versus UD and biological targets for more personalized treatment and new treatment developments for BD and UD depression. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  19. Synergetic effects of radiation stress and hot-carrier stress on the current gain of npn bipolar junction transistors

    International Nuclear Information System (INIS)

    Witczak, S.C.; Kosier, S.L.; Schrimpf, R.D.; Galloway, K.F.

    1994-01-01

    The combined effects of ionizing radiation and hot-carrier stress on the current gain of npn bipolar junction transistors were investigated. The analysis was carried out experimentally by examining the consequences of interchanging the order in which the two stress types were applied to identical transistors which were stressed to various levels of damage. The results indicate that the hot-carrier response of the transistor is improved by radiation damage, whereas hot-carrier damage has little effect on subsequent radiation stress. Characterization of the temporal progression of hot-carrier effects revealed that hot-carrier stress acts initially to reduce excess base current and improve current gain in irradiated transistors. PISCES simulations show that the magnitude of the peak electric-field within the emitter-base depletion region is reduced significantly by net positive oxide charges induced by radiation. The interaction of the two stress types is explained in a qualitative model based on the probability of hot-carrier injection determined by radiation damage and on the neutralization and compensation of radiation-induced positive oxide charges by injected electrons. The result imply that a bound on damage due to the combined stress types is achieved when hot-carrier stress precedes any irradiation

  20. Effects of irradiation on the components of implantable pacemakers

    International Nuclear Information System (INIS)

    Kawamura, Shinji; Ono, Seiji; Kuga, Noriyuki; Shiba, Tooru; Hirose, Tetsuo; Matoba, Masaru

    2003-01-01

    The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fibrillation. When the accumulated irradiation dose is increased, another failure can be seen in the output voltage of the pacemaker. The pacing output voltage dropped rapidly by about 40% at 30-88 Gy. Decreasing the output voltage results in pacing disorders, and heart failure may occur. In the telemetry data of the programmer, no change in output voltage could be detected, highlighting the difference between telemetry data and actual pacing data. (author)

  1. Ion production and bipolar fluxes in a high-current plasma-filled diode

    International Nuclear Information System (INIS)

    Ivanenkov, G.V.

    1982-01-01

    The model and the evolution of behaviour of binary layers (BL) in expanding plasma of high current plasma-filled diode are described. The model estimates ion current and the laws of plasma expansion at the stage of BL intensive growth. The density range (10 12 -10 15 cm -3 ) is determined in which diode impedance growth takes place in connection with BL appearance. The density of ion current at the outlet of diode is 10 A/cm 2

  2. 1978 Pacemaker Newspaper Awards: What Makes a Pacemaker?

    Science.gov (United States)

    Brasler, Wayne

    1979-01-01

    Lists the nine high school and college newspapers, and the one newsmagazine, that won Pacemaker Awards in 1978; discusses characteristics that make each of them outstanding, and provides reproductions of a front page from each publication. (GT)

  3. On the field-to-current conversion factors for large bipolar lightning discharge events in winter thunderstorms in Japan

    Science.gov (United States)

    Chen, Long; Zhang, Qilin; Hou, Wenhao; Tao, Yulang

    2015-07-01

    In this paper we have simulated the far-field waveform characteristic of large bipolar events (LBEs) occurred in winter thunderstorms in Japan and compared the field-to-current conversion factors (FCCFs) of LBEs with that of the lightning cloud-to-ground (CG) return stroke (RS) in summer thunderstorm. As for the physical process of LBEs, Wu et al. (2014) considered that LBEs may be very similar to the typical lightning RS (RS-like process) or caused by an initial continuous current pulse (ICC-like process) in upward lightning flashes. We assume that the lightning channel length of LBEs ranges from 500 m to 1000 m, and the height of tall object struck by LBEs is from 100 m to 300 m. By using the bouncing wave model, we found that only when the injected current waveform of LBEs is characterized with a symmetric Gaussian pulse, the simulated far-field waveform of LBEs both for RS-like process and ICC-like process is similar to that observed by Wu et al. (2014). For striking tall objects with heights from 100 m and 300 m, the FCCFs of LBEs are positively correlated with its channel length and derivatives of injected current waveform, and the FCCF for RS-like process is about similar to that for ICC-like process. However, the FCCFs of LBEs are very different from lightning RS in summer thunderstorm; that is to say, the FCCFs developed for the well-known lightning RS in summer thunderstorm are not suitable for LBEs.

  4. Development of the cardiac pacemaker

    Science.gov (United States)

    Liang, Xingqun; Evans, Sylvia M.

    2017-01-01

    The sinoatrial node (SAN) is the dominant pacemaker of the heart. Abnormalities in SAN formation and function can cause sinus arrhythmia, including sick sinus syndrome and sudden death. A better understanding of genes and signaling pathways that regulate SAN development and function is essential to develop more effective treatment to sinus arrhythmia, including biological pacemakers. In this review, we briefly summarize the key processes of SAN morphogenesis during development, and focus on the transcriptional network that drives SAN development. PMID:27770149

  5. Bipolar Disorder

    Science.gov (United States)

    Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They go ... The down feeling is depression. The causes of bipolar disorder aren't always clear. It runs in families. ...

  6. Prefronto-Cerebellar Transcranial Direct Current Stimulation Improves Sleep Quality in Euthymic Bipolar Patients: A Brief Report

    Directory of Open Access Journals (Sweden)

    Amedeo Minichino

    2014-01-01

    Full Text Available Introduction. Sleep problems are common in bipolar disorder (BD and may persist during the euthymic phase of the disease. The aim of the study was to improve sleep quality of euthymic BD patients through the administration of prefronto-cerebellar transcranial direct current stimulation (tDCS. Methods. 25 euthymic outpatients with a diagnosis of BD Type I or II have been enrolled in the study. tDCS montage was as follows: cathode on the right cerebellar cortex and anode over the left dorsolateral prefrontal cortex (DLPFC; the intensity of stimulation was set at 2 mA and delivered for 20 min/die for 3 consecutive weeks. The Pittsburgh Sleep Quality Index (PSQI was used to assess sleep quality at baseline and after the tDCS treatment. Results. PSQI total score and all PSQI subdomains, with the exception of “sleep medication,” significantly improved after treatment. Discussion. This is the first study where a positive effect of tDCS on the quality of sleep in euthymic BD patients has been reported. As both prefrontal cortex and cerebellum may play a role in regulating sleep processes, concomitant cathodal (inhibitory stimulation of cerebellum and anodal (excitatory stimulation of DLPFC may have the potential to modulate prefrontal-thalamic-cerebellar circuits leading to improvements of sleep quality.

  7. Optical beam induced current measurements based on two-photon absorption process in 4H-SiC bipolar diodes

    Energy Technology Data Exchange (ETDEWEB)

    Hamad, H.; Raynaud, C.; Bevilacqua, P.; Tournier, D.; Planson, D. [Ampère Laboratory - UMR 5005, 21, Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Vergne, B. [Franco-Allemand Institute of Saint-Louis ISL, 5, Rue du Général Cassagnou, 68300 Saint-Louis (France)

    2014-02-24

    Using a pulsed green laser with a wavelength of 532 nm, a duration pulse of ∼1 ns, and a mean power varying between 1 and 100 mW, induced photocurrents have been measured in 4H-SiC bipolar diodes. Considering the photon energy (2.33 eV) and the bandgap of 4H-SiC (3.2 eV), the generation of electron-hole pair by the conventional single photon absorption process should be negligible. The intensity of the measured photocurrents depends quadratically on the power beam intensity. This clearly shows that they are generated using two-photon absorption process. As in conventional OBIC (Optical Beam Induced Current), the measurements give an image of the electric field distribution in the structure under test, and the minority carrier lifetime can be extracted from the decrease of the photocurrent at the edge of the structure. The extracted minority carrier lifetime of 210 ns is consistent with results obtained in case of single photon absorption.

  8. Optical beam induced current measurements based on two-photon absorption process in 4H-SiC bipolar diodes

    International Nuclear Information System (INIS)

    Hamad, H.; Raynaud, C.; Bevilacqua, P.; Tournier, D.; Planson, D.; Vergne, B.

    2014-01-01

    Using a pulsed green laser with a wavelength of 532 nm, a duration pulse of ∼1 ns, and a mean power varying between 1 and 100 mW, induced photocurrents have been measured in 4H-SiC bipolar diodes. Considering the photon energy (2.33 eV) and the bandgap of 4H-SiC (3.2 eV), the generation of electron-hole pair by the conventional single photon absorption process should be negligible. The intensity of the measured photocurrents depends quadratically on the power beam intensity. This clearly shows that they are generated using two-photon absorption process. As in conventional OBIC (Optical Beam Induced Current), the measurements give an image of the electric field distribution in the structure under test, and the minority carrier lifetime can be extracted from the decrease of the photocurrent at the edge of the structure. The extracted minority carrier lifetime of 210 ns is consistent with results obtained in case of single photon absorption

  9. Simulation of electron and ion bipolar flow in high current diode with magnetic insulation

    International Nuclear Information System (INIS)

    Vrba, P.; Engelko, V.I.

    1990-08-01

    Numerical simulation of the formation of the collector ion flow in a magnetically insulated ion diode (MID) with a hollow cylindrical and cone-shaped cathode was studied. Such cathodes are often used for the production of tubular high current microsecond electron beams. The ions, emitted by the collector and born as a result of ionization of the residual gas by the electron beam, are focused into the cathode plasma region. This effect can adversely influence the diode operation

  10. Bipolar Disorder in Children

    Science.gov (United States)

    2014-01-01

    Although bipolar disorder historically was thought to only occur rarely in children and adolescents, there has been a significant increase in children and adolescents who are receiving this diagnosis more recently (Carlson, 2005). Nonetheless, the applicability of the current bipolar disorder diagnostic criteria for children, particularly preschool children, remains unclear, even though much work has been focused on this area. As a result, more work needs to be done to further the understanding of bipolar symptoms in children. It is hoped that this paper can assist psychologists and other health service providers in gleaning a snapshot of the literature in this area so that they can gain an understanding of the diagnostic criteria and other behaviors that may be relevant and be informed about potential approaches for assessment and treatment with children who meet bipolar disorder criteria. First, the history of bipolar symptoms and current diagnostic criteria will be discussed. Next, assessment strategies that may prove helpful for identifying bipolar disorder will be discussed. Then, treatments that may have relevance to children and their families will be discussed. Finally, conclusions regarding work with children who may have a bipolar disorder diagnosis will be offered. PMID:24800202

  11. Effects of irradiation on the components of implantable pacemakers

    CERN Document Server

    Kawamura, S; Kuga, N; Shiba, T; Hirose, T; Fujimoto, H; Toyoshima, T; Hyodo, K; Matoba, M

    2003-01-01

    The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fib...

  12. Wireless power transfer for a pacemaker application.

    Science.gov (United States)

    Vulfin, Vladimir; Sayfan-Altman, Shai; Ianconescu, Reuven

    2017-05-01

    An artificial pacemaker is a small medical device that uses electrical impulses, delivered by electrodes contracting the heart muscles, to regulate the beating of the heart. The pacemaker is implanted under the skin, and uses for many years regular non-rechargeable batteries. However, the demand for rechargeable batteries in pacemakers increased, and the aim of this work is to design an efficient charging system for pacemakers.

  13. 21 CFR 870.3670 - Pacemaker charger.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker charger. 870.3670 Section 870.3670 Food... DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3670 Pacemaker charger. (a) Identification. A pacemaker charger is a device used transcutaneously to recharge the batteries of a rechargeable...

  14. 21 CFR 870.3700 - Pacemaker programmers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker programmers. 870.3700 Section 870.3700...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3700 Pacemaker programmers. (a) Identification. A pacemaker programmer is a device used to change noninvasively one or more of...

  15. Influencing programmable pacemakers by radiation therapy

    International Nuclear Information System (INIS)

    Wilm, M.; Kronholz, H.L.; Schuetz, J.; Koch, T.

    1994-01-01

    More than 300,000 pacemakers are implanted worldwide. During radiation therapy a damage of the pacemaker elektronic is possible. Twenty pacemakers have been irradiated with photons or electrons experimentally in three different situations: a) pacemaker and pacemaker electrode outside of the irradiation field; b) pacemaker outside, pacemaker electrode inside the irradiation field; c) all things inside the irradiation field. The voltage in the pacemaker electrode produced by the electric field of the accelerator did not exceed 0.8 mV if the electrode was outside the irradiation field. Induced voltage was up to 1.2 mV during irradiation with electrons (18 MeV) and the electrode being inside the treatment field with more than two thirds of its length. After delivering of not more than 10 Gy (photons) to the pacemaker, a decreasing amplitude of the pacemaker pulse occurred. The pulse frequency did not show any deviation. This seems to signal a severe early irreversible damage of the pacemaker that may cause sudden breakdown days or weeks after radiation. Two pacemakers showed a complete breakdown after irradiation with not more than 10 Gy. The others had a complete breakdown beyond doses of 50 Gy. (orig./MG) [de

  16. Automatic Capture Verification in Pacemakers (Autocapture – Utility and Problems

    Directory of Open Access Journals (Sweden)

    Ruth Kam

    2004-04-01

    Full Text Available The concept of a closed – loop feedback system, that would automatically assess pacing threshold and self -adjust pacing output to ensure consistent myocardial capture, has many appeals. Enhancing patient safety in cases of an unexpected rise in threshold, reduced current drain, hence prolonging battery longevity and reducing the amount of physician intervention required are just some of the advantages. Autocapture (AC is a proprietary algorithm developed by St Jude Medical CRMD, Sylmar, CA, USA, (SJM that was the first to commercially provide these automatic functions in a single chamber pacemaker (Microny and Regency, and subsequently in a dual chamber pacemaker (Affinity, Entity and Identity family of pacemakers. This article reviews the conditions necessary for AC verification and performance and the problems encountered in clinical practice.

  17. Fifty years of pacemaker advancements.

    Science.gov (United States)

    Steinhaus, David

    2008-12-01

    A 1957 power blackout in Minnesota prompted C. Walton Lillehei, MD, a pioneer in open heart surgery, to ask Earl Bakken, the co-founder of Medtronic, Inc., to create a battery-operated pacemaker for pediatric patients. That conversation led to the development of the first external battery-operated pacemaker. That first bulky device is far removed from the tiny implantable computers available to heart patients today. Now, the size of two silver dollars stacked on top of one another, a pacemaker is prescribed for a person whose heart beats too slowly or pauses irregularly. Slightly larger devices have more recently evolved from pacing and regulating the heartbeat to being able to provide therapeutic high voltage shocks when needed to stop runaway fast heart rates, recording heart activity, and other physiologic functions, even resynchronizing the heart's chambers-all while providing information on the patient's condition and device performance to the doctor remotely or in the office.

  18. Noise-induced effects on multicellular biopacemaker spontaneous activity: Differences between weak and strong pacemaker cells

    Science.gov (United States)

    Aghighi, Alireza; Comtois, Philippe

    2017-09-01

    Self-organization of spontaneous activity of a network of active elements is important to the general theory of reaction-diffusion systems as well as for pacemaking activity to initiate beating of the heart. Monolayer cultures of neonatal rat ventricular myocytes, consisting of resting and pacemaker cells, exhibit spontaneous activation of their electrical activity. Similarly, one proposed approach to the development of biopacemakers as an alternative to electronic pacemakers for cardiac therapy is based on heterogeneous cardiac cells with resting and spontaneously beating phenotypes. However, the combined effect of pacemaker characteristics, density, and spatial distribution of the pacemaker cells on spontaneous activity is unknown. Using a simple stochastic pattern formation algorithm, we previously showed a clear nonlinear dependency of spontaneous activity (occurrence and amplitude of spontaneous period) on the spatial patterns of pacemaker cells. In this study, we show that this behavior is dependent on the pacemaker cell characteristics, with weaker pacemaker cells requiring higher density and larger clusters to sustain multicellular activity. These multicellular structures also demonstrated an increased sensitivity to voltage noise that favored spontaneous activity at lower density while increasing temporal variation in the period of activity. This information will help researchers overcome the current limitations of biopacemakers.

  19. Runaway pacemaker: a forgotten phenomenon?

    Science.gov (United States)

    Ortega, Daniel F; Sammartino, M Victoria; Pellegrino, Graciela M M; Barja, Luis D; Albina, Gaston; Segura, Eliseo V; Balado, Roberto; Laiño, Ruben; Giniger, Alberto G

    2005-11-01

    Runaway is an uncommon pacemaker dysfunction, characterized by fast and erratic spikes at non-physiological rates. This infrequent but potentially lethal failure mode may be related to low battery voltage. Four single chamber pacemaker patients were analyzed (Medtronic Minix ST 8330, Minneapolis, MN, had been implanted in two patients and two CPI Triumph VR 1124, St Paul, MN, in the other two). They had been admitted because of presyncopal episodes. Typical high rate stimuli at 2000 ppm alternating with pacing at 60-65 ppm were recorded in all ECGs. Lead system tests were normal. The pulse generators had to be replaced.

  20. Psychosocial responses of children to cardiac pacemakers.

    Science.gov (United States)

    Alpern, D; Uzark, K; Dick, M

    1989-03-01

    To examine the psychosocial responses of children and adolescents with a cardiac pacemaker and compare their responses to those of their peers, we evaluated 30 pediatric pacemaker patients, aged 7 to 19 years, and two age- and sex-matched comparison groups, including 30 patients with similar heart disease but without pacemakers and 30 physically healthy children, using standardized psychometric tests and a specific interview format. We postulated that children with pacemakers would experience greater stress in psychosocial adaptation. No significant differences on standardized measures of trait anxiety, self-competence, or self-esteem were found between the pacemaker group and the comparison groups. In contrast, pacemaker subjects were significantly (p less than 0.05) more external in their locus-of-control orientation than were healthy subjects, suggesting a diminished sense of personal control and less autonomy. Pacemaker subjects, particularly the older ones, had significantly (p less than 0.05) greater knowledge of pacemaker systems than did subjects in the other two groups, facilitating the use of intellectualization as a coping mechanism. The pacemaker patients were likely to be as fearful of social rejection as of potential pacemaker failure. All three groups identified potential negative peer reactions toward an individual with a pacemaker. The patients with cardiac disease but without pacemakers and the healthy subjects perceived significant (p less than 0.05) social and emotional differences between patients with pacemakers and their peers, but the pacemaker patients did not view themselves as different from their peers. This study demonstrates healthy psychosocial adaptation of children with cardiac pacemakers. Although these children appear to cope effectively with the stress of their life situation through the use of denial and intellectualization, they may experience problems both in the development of autonomy and in social isolation and rejection.

  1. Bipolar Plates for PEM Systems

    OpenAIRE

    Lædre, Sigrid

    2016-01-01

    Summary of thesis: The Bipolar Plate (BPP) is an important component in both Proton Exchange Membrane Fuel Cells (PEMFCs) and Proton Exchange Membrane Water Electrolyzers (PEMWEs). Bipolar plate material and processing constitutes for a large fraction of the cost and weight of a PEM cell stack. The main tasks for the bipolar plates in both systems are to separate single cell in a stack, conduct current between single cells and remove heat from active areas. In addition, the BPPs distribu...

  2. Is there an empirical link between impulsivity and suicidality in bipolar disorders? A review of the current literature and the potential psychological implications of the relationship.

    Science.gov (United States)

    Watkins, Hannah B; Meyer, Thomas D

    2013-08-01

    Suicide is highly prevalent among individuals with bipolar disorder and understanding the factors that increase risk for suicide may help to develop targeted interventions to prevent attempts. Impulsivity is thought to be an influential factor associated with suicidality and is also discussed as a key construct of bipolar disorder. The aim of this paper was to systematically review the current evidence to examine the association between impulsivity and suicidality in bipolar disorder. PsycInfo, Medline, and Web of Knowledge databases were searched for articles published up until March 2012. Papers were included if they assessed an adult sample of individuals with bipolar disorders, focused on suicidality (ideation with intent to die, suicide attempts, or completion), and used a validated measure to determine impulsivity. Sixteen papers were identified. Contrary to widespread belief, we found (i) a very inconsistent picture of results including positive, negative, and insignificant associations between impulsivity and suicidality; and (ii) some studies do not take into account important aspects such as state-trait or measurement issues. The link between suicidality and impulsivity is less straightforward than often assumed. Drawing clear conclusions about the association is hampered by factors such as inconsistencies in defining suicidality, measuring impulsivity, and differentiating between impulsivity as a personality trait and impulsivity as a state (e.g., a consequence of substance use or premeditation of the attempt). We suggest that the association is less direct and that psychological models (e.g., Joiner's theory of suicidality) can help foster a more in-depth understanding regarding the relationship. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Bipolar disorders

    DEFF Research Database (Denmark)

    Vieta, Eduard; Berk, Michael; Schulze, Thomas G

    2018-01-01

    Bipolar disorders are chronic and recurrent disorders that affect >1% of the global population. Bipolar disorders are leading causes of disability in young people as they can lead to cognitive and functional impairment and increased mortality, particularly from suicide and cardiovascular disease...... and accurate diagnosis is difficult in clinical practice as the onset of bipolar disorder is commonly characterized by nonspecific symptoms, mood lability or a depressive episode, which can be similar in presentation to unipolar depression. Moreover, patients and their families do not always understand...... a bipolar disorder from other conditions. Optimal early treatment of patients with evidence-based medication (typically mood stabilizers and antipsychotics) and psychosocial strategies is necessary....

  4. [Wide QRS tachycardia preceded by pacemaker spikes].

    Science.gov (United States)

    Romero, M; Aranda, A; Gómez, F J; Jurado, A

    2014-04-01

    The differential diagnosis and therapeutic management of wide QRS tachycardia preceded by pacemaker spike is presented. The pacemaker-mediated tachycardia, tachycardia fibrillo-flutter in patients with pacemakers, and runaway pacemakers, have a similar surface electrocardiogram, but respond to different therapeutic measures. The tachycardia response to the application of a magnet over the pacemaker could help in the differential diagnosis, and in some cases will be therapeutic, as in the case of a tachycardia-mediated pacemaker. Although these conditions are diagnosed and treated in hospitals with catheterization laboratories using the application programmer over the pacemaker, patients presenting in primary care clinic and emergency forced us to make a diagnosis and treat the haemodynamically unstable patient prior to referral. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  5. First Degree Pacemaker Exit Block

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2016-10-01

    Full Text Available Usually atrial and ventricular depolarizations follow soon after the pacemaker stimulus (spike on the ECG. But there can be an exit block due to fibrosis at the electrode - tissue interface at the lead tip. This can increase the delay between the spike and atrial or ventricular depolarization.

  6. Circadian Pacemaker – Temperature Compensation

    NARCIS (Netherlands)

    Gerkema, Menno P.; Binder, Marc D.; Hirokawa, Nobutaka; Windhorst, Uwe

    2009-01-01

    One of the defining characteristics of circadian pacemakers and indicates the independence of the speed of circadian clock processes of environmental temperature. Mechanisms involved, so far not elucidated in full detail, entail at least two processes that are similarly affected by temperature

  7. Bipolar Disorder.

    Science.gov (United States)

    Spearing, Melissa

    Bipolar disorder, a brain disorder that causes unusual shifts in a person's mood, affects approximately one percent of the population. It commonly occurs in late adolescence and is often unrecognized. The diagnosis of bipolar disorder is made on the basis of symptoms, course of illness, and when possible, family history. Thoughts of suicide are…

  8. Pacemakers and Implantable Defibrillators: MedlinePlus Health Topic

    Science.gov (United States)

    ... ClinicalTrials.gov: Pacemaker, Artificial (National Institutes of Health) Journal Articles References and abstracts from MEDLINE/PubMed (National ... Leadless Cardiac Pacemakers: The Next Evolution in Pacemaker Technology. ... on Pacemakers and Implantable Defibrillators is the National Heart, Lung, and Blood Institute Other Languages Find health information in languages other than English on Pacemakers and ...

  9. Bipolar impedance-controlled sealing of the pulmonary artery with SealSafe G3 electric current: determination of bursting pressures in an ex vivo model.

    Science.gov (United States)

    Kirschbaum, Andreas; Kunz, Julia; Steinfeldt, Thorsten; Pehl, Anika; Meyer, Christian; Bartsch, Detlef K

    2014-12-01

    In every anatomic lung resection operation, the pulmonary artery itself or its branches must be sealed. This involves either stapling or ligating the vessels. Based on the positive results with the bipolar vessel sealing ≤7 mm in abdominal surgery the present study aimed to evaluate burst pressures of the pulmonary artery after sealing with the sealing instrument SealSafe G3 (Gebrüder Martin & CoKG, Tuttlingen, Germany). The whole pulmonary artery above the pulmonary valve was exposed up to the periphery of the left lung in freshly removed pig heart-lung blocks. A pressure-measuring cylinder was then implanted in the prepared vessel on the side at the main trunk of the pulmonary artery to determine the pressure in the vessel. After either ligation or bipolar sealing of the pulmonary artery, the pneumatic burst pressure (millimeters of mercury) was determined in a water bath. Three groups (n = 12 for each seal type) with different vessel diameters were examined: group 1: 0-6 mm, group 2: 7-12 mm, and group 3: >12 mm. In all cases, vessel sealing was performed with a MARSEAL 5 instrument (Gebrüder Martin & Co KG, Tuttlingen, Germany) and the SealSafe G3 current. The mean burst pressures of the individual groups (ligature and bipolar sealing) were compared using two-tailed, nonparametric Mann-Whitney U test. Significance was defined as P < 0.05. The mean burst pressures in group 1 were measured by 340 ± 13.4 mm Hg with ligature and 205 ± 44.4 mm Hg with bipolar sealing (P < 0.001). In group 2, the mean values obtained were 270 ± 28.2 mm Hg for ligature and 162 ± 36.0 mm Hg for bipolar sealing (P < 0.001). In group 3, the mean burst pressures for bipolar sealing were only 52.1 ± 15.1 mm Hg, whereas those for ligated vessels were 253 ± 46.9 mm Hg (P < 0.001). For this size of vessel the burst pressure was also determined after stapling. The mean value in this case was 230 ± 21.8 mm Hg. In all groups, the mean burst

  10. The study of electroplating trivalent CrC alloy coatings with different current densities on stainless steel 304 as bipolar plate of proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Wang, Hsiang-Cheng; Hou, Kung-Hsu; Lu, Chen-En; Ger, Ming-Der

    2014-01-01

    In this study, the trivalent Cr–C coatings were electroplated on stainless steel 304 (SS304) substrates for an application in bipolar plates (BPPs) that was because of coating's excellent electric conductivity and corrosion resistance. The images of scanning electron microscope showed that the thickness of the coatings was between 1.4 and 11.4 μm, which increased with increase of coating current density. The surface morphology of Cr–C plated at coating current density of 10 A/dm 2 was smooth, crack- and pinhole-free, while cracks and pinholes appearing in networks were observed apparently in the deposits plated at a higher coating current density. Additionally, the C content in the coating decreased with increasing the coating current density. Moreover, the polarization curve with different coating current densities (10, 30, 50 A/dm 2 ) exhibited the coating prepared at 10 A/dm 2 and 10 min possessing the best corrosion resistance (I corr = 9.360 × 10 −8 A/cm 2 ). The contact resistance of Cr–C plated at coating current density of 10 A/dm 2 was the lowest (16.54 mΩ cm 2 at 150 N cm −2 ), which showed great potential of application. The single cell test with Cr–C coated SS304 prepared at coating current density of 10 A/dm 2 as BPPs showed the highest current density (about 791.532 mA/cm 2 ) and power density (about 270.150 mW/cm 2 ). - Highlights: • The Cr–C coatings on steel are electroplated for utilization as bipolar plate. • The electrical conductivity and corrosion resistance increase with carbon content. • The power density of Cr–C coated steel is superior to the bare steel

  11. The study of electroplating trivalent CrC alloy coatings with different current densities on stainless steel 304 as bipolar plate of proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hsiang-Cheng [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Hou, Kung-Hsu, E-mail: khou@ndu.edu.tw [Department of Power Vehicle and Systems Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Lu, Chen-En [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Ger, Ming-Der [Department of Applied Chemistry and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China)

    2014-11-03

    In this study, the trivalent Cr–C coatings were electroplated on stainless steel 304 (SS304) substrates for an application in bipolar plates (BPPs) that was because of coating's excellent electric conductivity and corrosion resistance. The images of scanning electron microscope showed that the thickness of the coatings was between 1.4 and 11.4 μm, which increased with increase of coating current density. The surface morphology of Cr–C plated at coating current density of 10 A/dm{sup 2} was smooth, crack- and pinhole-free, while cracks and pinholes appearing in networks were observed apparently in the deposits plated at a higher coating current density. Additionally, the C content in the coating decreased with increasing the coating current density. Moreover, the polarization curve with different coating current densities (10, 30, 50 A/dm{sup 2}) exhibited the coating prepared at 10 A/dm{sup 2} and 10 min possessing the best corrosion resistance (I{sub corr} = 9.360 × 10{sup −8} A/cm{sup 2}). The contact resistance of Cr–C plated at coating current density of 10 A/dm{sup 2} was the lowest (16.54 mΩ cm{sup 2} at 150 N cm{sup −2}), which showed great potential of application. The single cell test with Cr–C coated SS304 prepared at coating current density of 10 A/dm{sup 2} as BPPs showed the highest current density (about 791.532 mA/cm{sup 2}) and power density (about 270.150 mW/cm{sup 2}). - Highlights: • The Cr–C coatings on steel are electroplated for utilization as bipolar plate. • The electrical conductivity and corrosion resistance increase with carbon content. • The power density of Cr–C coated steel is superior to the bare steel.

  12. Application of RI power sources to cardiac pacemakers and aftercare in its implantation

    International Nuclear Information System (INIS)

    Hori, Motokazu

    1974-01-01

    RI power sources have long life when they are implanted into human bodies together with cardiac pacemakers, as compared with e.g. mercury batteries. Therefore, the frequency of their replacement can be by far less. However, there are the problems of radiation protection, high cost, availability, etc. The following matters are described: The cardiac pacemaker and its power supply, implantation into human body, problems with patients and conventional power sources; the current state of RI power sources for cardiac pacemakers, including plutonium-238 RTG and 147 Pm and 3 H batteries; and problems with the RI power sources. (Mori, K.)

  13. Bipolar and unipolar resistive switching behaviors of sol–gel-derived SrTiO3 thin films with different compliance currents

    International Nuclear Information System (INIS)

    Tang, M H; Wang, Z P; Zeng, Z Q; Xu, X L; Wang, G Y; Zhang, L B; Xiao, Y G; Yang, S B; Jiang, B; Li, J C; He, J

    2011-01-01

    The SrTiO 3 (STO) thin films on a Pt/Ti/SiO 2 /Si substrate were synthesized using a sol–gel method to form a metal–insulator–metal structure. This device shows the bipolar resistance switching (BRS) behavior for a compliance current I cc of less than 0.1 mA but exhibits soft breakdown at a higher level of compliance current. A transition from the BRS behavior to the stable unipolar resistive switching behavior (URS) was also observed. We found that the BRS behavior may be controlled by the structure interface while the URS behavior is likely bulk controlled. Our study indicates that the external compliance current is a key factor in resistance switching phenomenon of STO thin films

  14. Runaway pacemaker: a still existing complication and therapeutic guidelines

    DEFF Research Database (Denmark)

    Mickley, H; Andersen, C; Nielsen, L H

    1989-01-01

    Runaway pacemaker is a rare, but still existing potential lethal complication in permanent pacemakers. Within 4 1/2 years, we saw two cases of runaway pacemaker in patients with multiprogrammable, VVI pacemakers (Siemens-Elema, Model 668). In both cases a pacemaker-induced ventricular tachycardia...... pacemaker may be connected to the permanent pacing lead. Thereafter, the lead can be safely cut. As an alternative, a temporary transvenous pacing lead may be established prior to disconnecting the permanent pacing lead....

  15. On the Evolution of the Cardiac Pacemaker

    Directory of Open Access Journals (Sweden)

    Silja Burkhard

    2017-04-01

    Full Text Available The rhythmic contraction of the heart is initiated and controlled by an intrinsic pacemaker system. Cardiac contractions commence at very early embryonic stages and coordination remains crucial for survival. The underlying molecular mechanisms of pacemaker cell development and function are still not fully understood. Heart form and function show high evolutionary conservation. Even in simple contractile cardiac tubes in primitive invertebrates, cardiac function is controlled by intrinsic, autonomous pacemaker cells. Understanding the evolutionary origin and development of cardiac pacemaker cells will help us outline the important pathways and factors involved. Key patterning factors, such as the homeodomain transcription factors Nkx2.5 and Shox2, and the LIM-homeodomain transcription factor Islet-1, components of the T-box (Tbx, and bone morphogenic protein (Bmp families are well conserved. Here we compare the dominant pacemaking systems in various organisms with respect to the underlying molecular regulation. Comparative analysis of the pathways involved in patterning the pacemaker domain in an evolutionary context might help us outline a common fundamental pacemaker cell gene programme. Special focus is given to pacemaker development in zebrafish, an extensively used model for vertebrate development. Finally, we conclude with a summary of highly conserved key factors in pacemaker cell development and function.

  16. Epithermal neutron beam interference with cardiac pacemakers

    International Nuclear Information System (INIS)

    Koivunoro, H.; Serén, T.; Hyvönen, H.; Kotiluoto, P.; Iivonen, P.; Auterinen, I.; Seppälä, T.; Kankaanranta, L.; Pakarinen, S.; Tenhunen, M.; Savolainen, S.

    2011-01-01

    In this paper, a phantom study was performed to evaluate the effect of an epithermal neutron beam irradiation on the cardiac pacemaker function. Severe malfunction occurred in the pacemakers after substantially lower dose from epithermal neutron irradiation than reported in the fast neutron or photon beams at the same dose rate level. In addition the pacemakers got activated, resulting in nuclides with half-lives from 25 min to 115 d. We suggest that BNCT should be administrated only after removal of the pacemaker from the vicinity of the tumor.

  17. On the Evolution of the Cardiac Pacemaker

    Science.gov (United States)

    Burkhard, Silja; van Eif, Vincent; Garric, Laurence; Christoffels, Vincent M.; Bakkers, Jeroen

    2017-01-01

    The rhythmic contraction of the heart is initiated and controlled by an intrinsic pacemaker system. Cardiac contractions commence at very early embryonic stages and coordination remains crucial for survival. The underlying molecular mechanisms of pacemaker cell development and function are still not fully understood. Heart form and function show high evolutionary conservation. Even in simple contractile cardiac tubes in primitive invertebrates, cardiac function is controlled by intrinsic, autonomous pacemaker cells. Understanding the evolutionary origin and development of cardiac pacemaker cells will help us outline the important pathways and factors involved. Key patterning factors, such as the homeodomain transcription factors Nkx2.5 and Shox2, and the LIM-homeodomain transcription factor Islet-1, components of the T-box (Tbx), and bone morphogenic protein (Bmp) families are well conserved. Here we compare the dominant pacemaking systems in various organisms with respect to the underlying molecular regulation. Comparative analysis of the pathways involved in patterning the pacemaker domain in an evolutionary context might help us outline a common fundamental pacemaker cell gene programme. Special focus is given to pacemaker development in zebrafish, an extensively used model for vertebrate development. Finally, we conclude with a summary of highly conserved key factors in pacemaker cell development and function. PMID:29367536

  18. Epithermal neutron beam interference with cardiac pacemakers

    Energy Technology Data Exchange (ETDEWEB)

    Koivunoro, H., E-mail: hanna.koivunoro@helsinki.fi [Department of Physics, P.O.B. 64, FI-00014 University of Helsinki (Finland)] [Department of Oncology, Helsinki University Central Hospital, P.O.B. 180, FIN-00029 HUS (Finland)] [Boneca Corporation, Finland, Filnland (Finland); Seren, T. [VTT Technical Research Centre of Finland (Finland); Hyvoenen, H. [Boneca Corporation, Finland, Filnland (Finland); Kotiluoto, P. [VTT Technical Research Centre of Finland (Finland); Iivonen, P. [St. Jude Medical (Finland); Auterinen, I. [VTT Technical Research Centre of Finland (Finland); Seppaelae, T.; Kankaanranta, L. [Department of Oncology, Helsinki University Central Hospital, P.O.B. 180, FIN-00029 HUS (Finland); Pakarinen, S. [Department of Cardiology, Helsinki University Central Hospital (Finland); Tenhunen, M. [Department of Oncology, Helsinki University Central Hospital, P.O.B. 180, FIN-00029 HUS (Finland); Savolainen, S. [HUS Helsinki Medical Imaging Center, Helsinki University Central Hospital (Finland)

    2011-12-15

    In this paper, a phantom study was performed to evaluate the effect of an epithermal neutron beam irradiation on the cardiac pacemaker function. Severe malfunction occurred in the pacemakers after substantially lower dose from epithermal neutron irradiation than reported in the fast neutron or photon beams at the same dose rate level. In addition the pacemakers got activated, resulting in nuclides with half-lives from 25 min to 115 d. We suggest that BNCT should be administrated only after removal of the pacemaker from the vicinity of the tumor.

  19. The nuclear pacemaker: Is renewed interest warranted

    International Nuclear Information System (INIS)

    Parsonnet, V.; Berstein, A.D.; Perry, G.Y.

    1990-01-01

    From 1973 through 1987, 155 radioisotope-powered nuclear pacemakers were implanted in 132 patients at the Newark Beth Israel Medical Center. The longevity of the first 15 devices, all of which were fixed-rate (VOO) pacemakers, was significantly better than that of 15 lithium-chemistry demand (VVI) pacemakers used as control devices (p = 0.0002). Of the entire cohort of 155 nuclear pacemakers, 136 were VVI devices and 19 were VOO units. The patients with VOO pacemakers needed reoperations more often than did those with VVI pacemakers, chiefly for mode change (p less than 0.001). Power-source failure was observed in only 1 case, but 47 nuclear pacemakers were removed for other reasons, including component malfunction (15 units), mode change (12 units), high pacing thresholds (8 units) and lead or connector problems (5 units). The actuarial survival at 15 years was 99% for power sources and 82% for the entire pacing systems (pulse generators plus leads). The frequency of malignancy was similar to that of the population at large and primary tumor sites were randomly distributed. Deaths most commonly were due to cardiac causes (68%). Thus, nuclear pacemakers are safe and reliable and their greater initial cost appears to be offset by their longevity and the resulting decrease in the frequency of reoperations. It is reasonable to suggest that further use be made of long-lasting nuclear power sources for modern pacemakers and other implantable rhythm-management devices

  20. Pacemaker rate and depolarization block in nigral dopamine neurons: a somatic sodium channel balancing act

    Science.gov (United States)

    Tucker, Kristal R.; Huertas, Marco A.; Horn, John P.; Canavier, Carmen C.; Levitan, Edwin S.

    2012-01-01

    Midbrain dopamine (DA) neurons are slow intrinsic pacemakers that undergo depolarization (DP) block upon moderate stimulation. Understanding DP block is important because it has been correlated with the clinical efficacy of chronic antipsychotic drug treatment. Here we describe how voltage-gated sodium (NaV) channels regulate DP block and pacemaker activity in DA neurons of the substantia nigra using rat brain slices. The distribution, density and gating of NaV currents were manipulated by blocking native channels with tetrodotoxin and by creating virtual channels and anti-channels with dynamic clamp. Although action potentials initiate in the axon initial segment (AIS) and NaV channels are distributed in multiple dendrites, selective reduction of NaV channel activity in the soma was sufficient to decrease pacemaker frequency and increase susceptibility to DP block. Conversely, increasing somatic NaV current density raised pacemaker frequency and lowered susceptibility to DP block. Finally, when NaV currents were restricted to the soma, pacemaker activity occurred at abnormally high rates due to excessive local subthreshold NaV current. Together with computational simulations, these data show that both the slow pacemaker rate and the sensitivity to DP block that characterizes DA neurons result from the low density of somatic NaV channels. More generally, we conclude that the somatodendritic distribution of NaV channels is a major determinant of repetitive spiking frequency. PMID:23077037

  1. Validation of the Netherlands pacemaker patient registry

    NARCIS (Netherlands)

    Dijk, WA; Kingma, T; Hooijschuur, CAM; Dassen, WRM; Hoorntje, JCA; van Gelder, LM

    1997-01-01

    This paper deals with the validation of the information stored in the Netherlands central pacemaker patient database. At this moment the registry database contains information on more than 70500 patients, 85000 pacemakers and 90000 leads. The validation procedures consisted of an internal

  2. On the Evolution of the Cardiac Pacemaker

    NARCIS (Netherlands)

    Burkhard, Silja; van Eif, Vincent; Garric, Laurence; Christoffels, Vincent M.; Bakkers, Jeroen

    2017-01-01

    The rhythmic contraction of the heart is initiated and controlled by an intrinsic pacemaker system. Cardiac contractions commence at very early embryonic stages and coordination remains crucial for survival. The underlying molecular mechanisms of pacemaker cell development and function are still not

  3. Feasibility of pacemaker therapy after dynamic cardiomyoplasty

    NARCIS (Netherlands)

    Van den Berg, MP; Nagelkerke, D; Brouwer, RMHJ; Mulder, H; De Boer, H; Crijns, HJGM

    1999-01-01

    A 54-year-old man presented with total atrioventricular (AV) block 3 months after dynamic cardiomyoplasty was performed because of heart failure due to idiopathic dilated cardiomyopathy. Though the cardiomyostimulator acted as a back-up pacemaker, a DDDR pacemaker was implanted to optimize

  4. A minimal model for a slow pacemaking neuron

    International Nuclear Information System (INIS)

    Zakharov, D.G.; Kuznetsov, A.

    2012-01-01

    Highlights: ► We have constructed a phenomenological model for slow pacemaking neurons. ► The model implements a nonlinearity introduced by an ion-dependent current. ► The new nonlinear dependence allows for differentiating responses to various stimuli. ► We discuss implications of our results for a broad class of neurons. - Abstract: We have constructed a phenomenological model for slow pacemaking neurons. These are neurons that generate very regular periodic oscillations of the membrane potential. Many of these neurons also differentially respond to various types of stimulation. The model is based on FitzHugh–Nagumo (FHN) oscillator and implements a nonlinearity introduced by a current that depends on an ion concentration. The comparison with the original FHN oscillator has shown that the new nonlinear dependence allows for differentiating responses to various stimuli. We discuss implications of our results for a broad class of neurons.

  5. Biofilm on artificial pacemaker: fiction or reality?

    Science.gov (United States)

    Santos, Ana Paula Azevedo; Watanabe, Evandro; Andrade, Denise de

    2011-11-01

    Cardiac pacing through cardiac pacemaker is one of the most promising alternatives in the treatment of arrhythmias, but it can cause reactions natural or complex reactions, either early or late. This study aimed to describe the scientific evidence on the risk of infection and biofilm formation associated with cardiac pacemaker. This is a study of integrative literature review. It included 14 publications classified into three thematic categories: diagnosis (microbiological and/or clinical), complications and therapy of infections. Staphylococcus epidermidis and Staphylococcus aureus were the microorganisms most frequently isolated. It was not possible to determine the incidence of infection associated with pacemakers, since the studies were generally of prevalence. In terms of therapy, the complete removal of pacemakers stood out, especially in cases of suspected biofilm. Still controversial is the use of systemic antibiotic prophylaxis in reducing the incidence of infection associated with implantation of a pacemaker.

  6. Isotopic cardiac pacemaker during pregnancy. Three cases

    International Nuclear Information System (INIS)

    Laurens, P.; Gavelle, P.; Maurice, P.; Haiat, R.; Chiche, P.

    1976-01-01

    Three cases of full term pregnancies, without complications, in women with isotopic pacemakers are reported. The newborn infants were normal. In one case, pregnancy occurred in a patient who already had a pacemaker. In two cases, the pacemaker was inserted during pregnancy (at 1 and 1/2 and 5 months respectively), in the treatment of syncopal attacks due to paroxysmal atrioventricular block. This type of pacemaker using a radioactive source (plutonium 238) is, by virtue of the low degree of radiation, harmless and may be used in women of childbearing age. Under the least favourable conditions (pacemaker box in abdominal situation), the dose delivered during pregnancy (57 mrem) is approximately 20 times less than the authorized dose (1125 mrem) [fr

  7. Inward-rectifying potassium (Kir) channels regulate pacemaker activity in spinal nociceptive circuits during early life

    Science.gov (United States)

    Li, Jie; Blankenship, Meredith L.; Baccei, Mark L.

    2013-01-01

    Pacemaker neurons in neonatal spinal nociceptive circuits generate intrinsic burst-firing and are distinguished by a lower “leak” membrane conductance compared to adjacent, non-bursting neurons. However, little is known about which subtypes of leak channels regulate the level of pacemaker activity within the developing rat superficial dorsal horn (SDH). Here we demonstrate that a hallmark feature of lamina I pacemaker neurons is a reduced conductance through inward-rectifying potassium (Kir) channels at physiological membrane potentials. Differences in the strength of inward rectification between pacemakers and non-pacemakers indicate the presence of functionally distinct Kir currents in these two populations at room temperature. However, Kir currents in both groups showed high sensitivity to block by extracellular Ba2+ (IC50 ~ 10 µM), which suggests the presence of ‘classical’ Kir (Kir2.x) channels in the neonatal SDH. The reduced Kir conductance within pacemakers is unlikely to be explained by an absence of particular Kir2.x isoforms, as immunohistochemical analysis revealed the expression of Kir2.1, Kir2.2 and Kir2.3 within spontaneously bursting neurons. Importantly, Ba2+ application unmasked rhythmic burst-firing in ~42% of non-bursting lamina I neurons, suggesting that pacemaker activity is a latent property of a sizeable population of SDH cells during early life. In addition, the prevalence of spontaneous burst-firing within lamina I was enhanced in the presence of high internal concentrations of free Mg2+, consistent with its documented ability to block Kir channels from the intracellular side. Collectively, the results indicate that Kir channels are key modulators of pacemaker activity in newborn central pain networks. PMID:23426663

  8. Radiotherapy for breast cancer and pacemaker

    International Nuclear Information System (INIS)

    Menard, J.; Campana, F.; Bollet, M.A.; Dendale, R.; Fournier-Bidoz, N.; Marchand, V.; Mazal, A.; Fourquet, A.; Kirova, Y.M.; Kirov, K.M.; Esteve, M.

    2011-01-01

    Purpose. - Patients with permanent cardiac pacemakers occasionally require radiotherapy. Therapeutic Irradiation may cause pacemakers to malfunction due to the effects of ionizing radiation or electromagnetic interference. We studied the breast cancer patients who needed breast and/or chest wall and lymph node irradiation to assess the feasibility and tolerance in this population of patients. Patients and methods. - From November 2008 to December 2009, more than 900 patients received radiotherapy for their breast cancer in our department using megavoltage linear accelerator (X 4-6 MV and electrons). Among them, seven patients were with permanent pacemaker. All patients have been treated to the breast and chest wall and/or lymph nodes. Total dose to breast and/or chest wall was 50 Gy/25 fractions and 46 Gy/23 fractions to lymph nodes. Patients who underwent conserving surgery followed by breast irradiation were boosted when indicated to tumour bed with 16 Gy/8 fractions. All patients were monitored everyday in presence of radiation oncologist to follow the function of their pacemaker. All pacemakers were controlled before and after radiotherapy by the patients' cardiologist. Results. - Seven patients were referred in our department for postoperative breast cancer radiotherapy. Among them, only one patient was declined for radiotherapy and underwent mastectomy without radiotherapy. In four cases the pacemaker was repositioned before the beginning of radiotherapy. Six patients, aged between 48 and 84 years underwent irradiation for their breast cancer. Four patients were treated with conserving surgery followed by breast radiotherapy and two with mastectomy followed by chest wall and internal mammary chain, supra- and infra-clavicular lymph node irradiation. The dose to the pacemaker generator was kept below 2 Gy. There was no pacemaker dysfunction observed during the radiotherapy. Conclusion. - The multidisciplinary work with position change of the pacemaker before

  9. Integrative Modeling of Electrical Properties of Pacemaker Cardiac Cells

    Science.gov (United States)

    Grigoriev, M.; Babich, L.

    2016-06-01

    This work represents modeling of electrical properties of pacemaker (sinus) cardiac cells. Special attention is paid to electrical potential arising from transmembrane current of Na+, K+ and Ca2+ ions. This potential is calculated using the NaCaX model. In this respect, molar concentration of ions in the intercellular space which is calculated on the basis of the GENTEX model is essential. Combined use of two different models allows referring this approach to integrative modeling.

  10. Early Intervention in Bipolar Disorder.

    Science.gov (United States)

    Vieta, Eduard; Salagre, Estela; Grande, Iria; Carvalho, André F; Fernandes, Brisa S; Berk, Michael; Birmaher, Boris; Tohen, Mauricio; Suppes, Trisha

    2018-05-01

    Bipolar disorder is a recurrent disorder that affects more than 1% of the world population and usually has its onset during youth. Its chronic course is associated with high rates of morbidity and mortality, making bipolar disorder one of the main causes of disability among young and working-age people. The implementation of early intervention strategies may help to change the outcome of the illness and avert potentially irreversible harm to patients with bipolar disorder, as early phases may be more responsive to treatment and may need less aggressive therapies. Early intervention in bipolar disorder is gaining momentum. Current evidence emerging from longitudinal studies indicates that parental early-onset bipolar disorder is the most consistent risk factor for bipolar disorder. Longitudinal studies also indicate that a full-blown manic episode is often preceded by a variety of prodromal symptoms, particularly subsyndromal manic symptoms, therefore supporting the existence of an at-risk state in bipolar disorder that could be targeted through early intervention. There are also identifiable risk factors that influence the course of bipolar disorder, some of them potentially modifiable. Valid biomarkers or diagnosis tools to help clinicians identify individuals at high risk of conversion to bipolar disorder are still lacking, although there are some promising early results. Pending more solid evidence on the best treatment strategy in early phases of bipolar disorder, physicians should carefully weigh the risks and benefits of each intervention. Further studies will provide the evidence needed to finish shaping the concept of early intervention. AJP AT 175 Remembering Our Past As We Envision Our Future April 1925: Interpretations of Manic-Depressive Phases Earl Bond and G.E. Partridge reviewed a number of patients with manic-depressive illness in search of a unifying endo-psychic conflict. They concluded that understanding either phase of illness was "elusive" and

  11. 21 CFR 870.3600 - External pacemaker pulse generator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External pacemaker pulse generator. 870.3600... pacemaker pulse generator. (a) Identification. An external pacemaker pulse generator is a device that has a... intrinsic pacing sytem until a permanent pacemaker can be implanted, or to control irregular heartbeats in...

  12. 21 CFR 870.3620 - Pacemaker lead adaptor.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker lead adaptor. 870.3620 Section 870.3620...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3620 Pacemaker lead adaptor. (a) Identification. A pacemaker lead adaptor is a device used to adapt a pacemaker lead so that it...

  13. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indirect pacemaker generator function analyzer... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker generator function analyzer is an electrically powered device that is used to determine pacemaker function or...

  14. Damaging effect of therapeutic radiation on programmable pacemakers

    International Nuclear Information System (INIS)

    Adamec, R.; Haefliger, J.M.; Killisch, J.P.; Niederer, J.; Jaquet, P.

    1982-01-01

    Two series of present-day pacemakers were tested in vitro with pulsed x-ray radiation. The first series of 12 pacemakers consisted of 10 different types and models of demand pacemakers (VVI). The second series of 13 pacemakers had 9 different types and models of programmable pacemakers. Unlike the first series which showed only mild changes in frequency and pulse width, all but four of the programmable pacemakers presented sudden complete failure after different radiation doses. We conclude that direct pulse radiation at therapeutic levels of programmable pacemakers should be avoided

  15. Pacemakers charging using body energy

    Directory of Open Access Journals (Sweden)

    Dinesh Bhatia

    2010-01-01

    Full Text Available Life-saving medical implants like pacemakers and defibrillators face a big drawback that their batteries eventually run out and patients require frequent surgery to have these batteries replaced. With the advent of technology, alternatives can be provided for such surgeries. To power these devices, body energy harvesting techniques may be employed. Some of the power sources are patient′s heartbeat, blood flow inside the vessels, movement of the body parts, and the body temperature (heat. Different types of sensors are employed, such as for sensing the energy from the heartbeat the piezoelectric and semiconducting coupled nanowires are used that convert the mechanical energy into electricity. Similarly, for sensing the blood flow energy, nanogenerators driven by ultrasonic waves are used that have the ability to directly convert the hydraulic energy in human body to electrical energy. Another consideration is to use body heat employing biothermal battery to generate electricity using multiple arrays of thermoelectric generators built into an implantable chip. These generators exploit the well-known thermocouple effect. For the biothermal device to work, it needs a 2°C temperature difference across it. But there are many parts of the body where a temperature difference of 5°C exists - typically in the few millimeters just below the skin, where it is planned to place this device. This study focuses on using body heat as an alternative energy source to recharge pacemaker batteries and other medical devices and prevent the possibility of life-risk during repeated surgery.

  16. Universal pacemaker of genome evolution.

    Science.gov (United States)

    Snir, Sagi; Wolf, Yuri I; Koonin, Eugene V

    2012-01-01

    A fundamental observation of comparative genomics is that the distribution of evolution rates across the complete sets of orthologous genes in pairs of related genomes remains virtually unchanged throughout the evolution of life, from bacteria to mammals. The most straightforward explanation for the conservation of this distribution appears to be that the relative evolution rates of all genes remain nearly constant, or in other words, that evolutionary rates of different genes are strongly correlated within each evolving genome. This correlation could be explained by a model that we denoted Universal PaceMaker (UPM) of genome evolution. The UPM model posits that the rate of evolution changes synchronously across genome-wide sets of genes in all evolving lineages. Alternatively, however, the correlation between the evolutionary rates of genes could be a simple consequence of molecular clock (MC). We sought to differentiate between the MC and UPM models by fitting thousands of phylogenetic trees for bacterial and archaeal genes to supertrees that reflect the dominant trend of vertical descent in the evolution of archaea and bacteria and that were constrained according to the two models. The goodness of fit for the UPM model was better than the fit for the MC model, with overwhelming statistical significance, although similarly to the MC, the UPM is strongly overdispersed. Thus, the results of this analysis reveal a universal, genome-wide pacemaker of evolution that could have been in operation throughout the history of life.

  17. Pacemakers charging using body energy

    Science.gov (United States)

    Bhatia, Dinesh; Bairagi, Sweeti; Goel, Sanat; Jangra, Manoj

    2010-01-01

    Life-saving medical implants like pacemakers and defibrillators face a big drawback that their batteries eventually run out and patients require frequent surgery to have these batteries replaced. With the advent of technology, alternatives can be provided for such surgeries. To power these devices, body energy harvesting techniques may be employed. Some of the power sources are patient's heartbeat, blood flow inside the vessels, movement of the body parts, and the body temperature (heat). Different types of sensors are employed, such as for sensing the energy from the heartbeat the piezoelectric and semiconducting coupled nanowires are used that convert the mechanical energy into electricity. Similarly, for sensing the blood flow energy, nanogenerators driven by ultrasonic waves are used that have the ability to directly convert the hydraulic energy in human body to electrical energy. Another consideration is to use body heat employing biothermal battery to generate electricity using multiple arrays of thermoelectric generators built into an implantable chip. These generators exploit the well-known thermocouple effect. For the biothermal device to work, it needs a 2°C temperature difference across it. But there are many parts of the body where a temperature difference of 5°C exists – typically in the few millimeters just below the skin, where it is planned to place this device. This study focuses on using body heat as an alternative energy source to recharge pacemaker batteries and other medical devices and prevent the possibility of life-risk during repeated surgery. PMID:21814432

  18. Bipolar Disorder

    Science.gov (United States)

    ... one or other traumatic event Drug or alcohol abuse Complications Left untreated, bipolar disorder can result in serious problems that affect every area of your life, such as: Problems related to drug and alcohol use Suicide or suicide attempts Legal or financial problems Damaged ...

  19. Neutrality in bipolar structures

    DEFF Research Database (Denmark)

    Montero, Javier; Rodríguez, J. Tinguaro; Franco, Camilo

    2014-01-01

    In this paper, we want to stress that bipolar knowledge representation naturally allows a family of middle states which define as a consequence different kinds of bipolar structures. These bipolar structures are deeply related to the three types of bipolarity introduced by Dubois and Prade, but our...... approach offers a systematic explanation of how such bipolar structures appear and can be identified....

  20. Radiation protection for pacemakers with radionuclide batteries

    International Nuclear Information System (INIS)

    Stieve, F.E.

    1976-01-01

    Radionuclide batteries ( 147 Pm, 238 Pu) in pacemakers bring risks for the patient and the environment, if the radioactive material cannot be secured for subsequent application or for safe end storage. This is why the expenditure connected with pacemakers is very high. So the application of such pacemakers is only indicated when the patient's expectation of life is presumably higher than 5-10 years, when there are no other diseases besides cardiac dysrhytmia, and when the securing of the radionuclide batteries is guaranteed. (orig.) [de

  1. Minimally Invasive Epicardial Pacemaker Implantation in Neonates with Congenital Heart Block.

    Science.gov (United States)

    Costa, Roberto; Silva, Katia Regina da; Martinelli Filho, Martino; Carrillo, Roger

    2017-10-01

    Few studies have characterized the surgical outcomes following epicardial pacemaker implantation in neonates with congenital complete atrioventricular block (CCAVB). This study sought to assess the long-term outcomes of a minimally invasive epicardial approach using a subxiphoid access for pacemaker implantation in neonates. Between July 2002 and February 2015, 16 consecutive neonates underwent epicardial pacemaker implantation due to CCAVB. Among these, 12 (75.0%) had congenital heart defects associated with CCAVB. The patients had a mean age of 4.7 ± 5.3 days and nine (56.3%) were female. Bipolar steroid-eluting epicardial leads were implanted in all patients through a minimally invasive subxiphoid approach and fixed on the diaphragmatic ventricular surface. The pulse generator was placed in an epigastric submuscular position. All procedures were successful, with no perioperative complications or early deaths. Mean operating time was 90.2 ± 16.8 minutes. None of the patients displayed pacing or sensing dysfunction, and all parameters remained stable throughout the follow-up period of 4.1 ± 3.9 years. Three children underwent pulse generator replacement due to normal battery depletion at 4.0, 7.2, and 9.0 years of age without the need of ventricular lead replacement. There were two deaths at 12 and 325 days after pacemaker implantation due to bleeding from thrombolytic use and progressive refractory heart failure, respectively. Epicardial pacemaker implantation through a subxiphoid approach in neonates with CCAVB is technically feasible and associated with excellent surgical outcomes and pacing lead longevity.

  2. Resonant Hall effect under generation of a self-sustaining mode of spin current in nonmagnetic bipolar conductors with identical characters between holes and electrons

    Science.gov (United States)

    Sakai, Masamichi; Takao, Hiraku; Matsunaga, Tomoyoshi; Nishimagi, Makoto; Iizasa, Keitaro; Sakuraba, Takahito; Higuchi, Koji; Kitajima, Akira; Hasegawa, Shigehiko; Nakamura, Osamu; Kurokawa, Yuichiro; Awano, Hiroyuki

    2018-03-01

    We have proposed an enhancement mechanism of the Hall effect, the signal of which is amplified due to the generation of a sustaining mode of spin current. Our analytic derivations of the Hall resistivity revealed the conditions indispensable for the observation of the effect: (i) the presence of the transverse component of an effective electric field due to spin splitting in chemical potential in addition to the longitudinal component; (ii) the simultaneous presence of holes and electrons each having approximately the same characteristics; (iii) spin-polarized current injection from magnetized electrodes; (iv) the boundary condition for the transverse current (J c, y = 0). The model proposed in this study was experimentally verified by using van der Pauw-type Hall devices consisting of the nonmagnetic bipolar conductor YH x (x ≃ 2) and TbFeCo electrodes. Replacing Au electrodes with TbFeCo electrodes alters the Hall resistivity from the ordinary Hall effect to the anomalous Hall-like effect with an enhancement factor of approximately 50 at 4 T. We interpreted the enhancement phenomenon in terms of the present model.

  3. Interference with cardiac pacemakers by magnetic resonance imaging: are there irreversible changes at 0.5 Tesla?

    Science.gov (United States)

    Vahlhaus, C; Sommer, T; Lewalter, T; Schimpf, R; Schumacher, B; Jung, W; Lüderitz, B

    2001-04-01

    The safety and feasibility of magnetic resonance imaging (MRI) in patients with cardiac pacemakers is an issue of gaining significance. The effect of MRI on patients' pacemaker systems has only been analyzed retrospectively in some case reports. Therefore, this study prospectively investigated if MRI causes irreversible changes in patients' pacemaker systems. The effect of MRI at 0.5 Tesla on sensing and stimulation thresholds, lead impedance and battery voltage, current, and impedance was estimated during 34 MRI examinations in 32 patients with implanted pacemakers. After measurements at baseline and with documentation of intrinsic rhythm and modification of the pacing mode, patients underwent MRI. The rest of the function time of the pacemaker was calculated. Measurements were again performed after 99.5 +/- 29.6 minutes (mean +/- SD), immediately after MRI examination, and 3 months later. Lead impedance and sensing and stimulation thresholds did not change after MRI. Battery voltage decreased immediately after MRI and recovered 3 months later. Battery current and impedance tended to increase. The calculated rest of function time did not change immediately after MRI. MRI affected neither pacemaker programmed data, nor the ability to interrogate, program, or use telemetry. Surprisingly, in the gantry of the scanner, temporary deactivation of the reed switch occurred in 12 of 32 patients when positioned in the center of the magnetic field. Missing activation of the reed switch through the static magnetic field at 0.5 Tesla is not unusual. MRI at 0.5 Tesla does not cause irreversible changes in patients' pacemaker systems.

  4. Bipolar disorder: an update | Outhoff | South African Family Practice

    African Journals Online (AJOL)

    Bipolar disorder, characterised by alternating discrete episodes of (hypo)mania and depression, provides unique diagnostic and treatment challenges. Updated diagnostic (DSM-5) and current pharmacological treatment recommendations are briefly reviewed here. Keywords: bipolar disorder; diagnosis; evidence-based ...

  5. Bipolar mood cycles and lunar tidal cycles.

    Science.gov (United States)

    Wehr, T A

    2018-04-01

    In 17 patients with rapid cycling bipolar disorder, time-series analyses detected synchronies between mood cycles and three lunar cycles that modulate the amplitude of the moon's semi-diurnal gravimetric tides: the 14.8-day spring-neap cycle, the 13.7-day declination cycle and the 206-day cycle of perigee-syzygies ('supermoons'). The analyses also revealed shifts among 1:2, 1:3, 2:3 and other modes of coupling of mood cycles to the two bi-weekly lunar cycles. These shifts appear to be responses to the conflicting demands of the mood cycles' being entrained simultaneously to two different bi-weekly lunar cycles with slightly different periods. Measurements of circadian rhythms in body temperature suggest a biological mechanism through which transits of one of the moon's semi-diurnal gravimetric tides might have driven the patients' bipolar cycles, by periodically entraining the circadian pacemaker to its 24.84-h rhythm and altering the pacemaker's phase-relationship to sleep in a manner that is known to cause switches from depression to mania.

  6. Bipolar electrochemistry.

    Science.gov (United States)

    Fosdick, Stephen E; Knust, Kyle N; Scida, Karen; Crooks, Richard M

    2013-09-27

    A bipolar electrode (BPE) is an electrically conductive material that promotes electrochemical reactions at its extremities (poles) even in the absence of a direct ohmic contact. More specifically, when sufficient voltage is applied to an electrolyte solution in which a BPE is immersed, the potential difference between the BPE and the solution drives oxidation and reduction reactions. Because no direct electrical connection is required to activate redox reactions, large arrays of electrodes can be controlled with just a single DC power supply or even a battery. The wireless aspect of BPEs also makes it possible to electrosynthesize and screen novel materials for a wide variety of applications. Finally, bipolar electrochemistry enables mobile electrodes, dubbed microswimmers, that are able to move freely in solution. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Devices That May Interfere with Pacemakers

    Science.gov (United States)

    ... Communications Commission (FCC) makes new frequencies available. Newer cellphones using these new frequencies might make pacemakers less reliable. A group of cellphone companies is studying that possibility. Bluetooth® headsets do ...

  8. Transtorno bipolar

    Directory of Open Access Journals (Sweden)

    Alda Martin

    1999-01-01

    Full Text Available Os resultados de estudos de famílias sugerem que o transtorno bipolar tenha uma base genética. Essa hipótese foi reforçada em estudos de adoção e de gêmeos. A herança do transtorno bipolar é complexa, envolve vários genes, além de apresentar heterogeneidade e interação entre fatores genéticos e não-genéticos. Achados, que já foram replicados, já implicaram os cromossomos 4, 12, 18 e 21, entre outros, na busca por genes de suscetibilidade. Os resultados mais promissores foram obtidos através de estudos de ligação. Por outro lado, os estudos de associação geraram dados interessantes, mas ainda vagos. Os estudos de populações de pacientes homogêneos e a melhor definição do fenótipo deverão contribuir para avanços futuros. A identificação dos genes relacionados ao transtorno bipolar irá permitir o melhor entendimento e tratamento dessa doença.

  9. Nuclear-powered pacemaker fuel cladding study

    International Nuclear Information System (INIS)

    Shoup, R.L.

    1976-01-01

    The composite of metals and alloys used in the fabrication of 238 Pu cardiac pacemaker fuel capsules resists the effects of high temperatures, high mechanical forces, and chemical corrosives and provides more than adequate protection to the fuel pellet even from deliberate attempts to dissolve the cladding in inorganic acids. This does not imply that opening a pacemaker fuel capsule by inorganic acids is impossible but that it would not be a wise choice

  10. The effect of therapeutic x-radiation on a sample of pacemaker generators

    International Nuclear Information System (INIS)

    Maxted, K.J.

    1984-01-01

    Tests were made on nineteen generators, comprising seventeen types from five manufacturers and including four programmable units, and x-ray energies of about 4 MeV. The bipolar generators suffered no measureable damage and radiotherapy patients using these would appear not to be exposed to any hazard. Nor were any of the generators using entirely CMOS circuitry, including the programmable types, affected. Generators using hybrid bipolar and CMOS circuitry were damaged by radiation exposure, the majority of these being Medtronic pacemakers. Transient recovery of function followed by total failure suggested that even a transient loss of function must be regarded as a precursor to permanent damage. This transient effect indicates that it is most likely the CMOS circuit element that is affected. (U.K.)

  11. Pacemaker diagnostics in atrial fibrillation: limited usefulness for therapy initiation in a pacemaker practice.

    Science.gov (United States)

    Yedlapati, Neeraja; Fisher, John D

    2014-09-01

    We aimed to determine the practical value of pacemaker diagnostics for atrial fibrillation (AF) in an unselected general pacemaker practice, specifically workflow and initiation of anticoagulation or antiarrhythmic drug (AAD) therapy. We prospectively followed consecutive pacemaker interrogations over a period of 1 year to identify patients with AF (burden from 1% to 99%). We contacted referring physicians with AF details, and then determined whether the information resulted in therapeutic changes. Of the 1,100 pacemakers interrogated, 728 were dual chamber (DDDs) with AF diagnostic capability. AF was recorded in 73 (10%) but seven had limited information, leaving 66 patients; of these, 42 (63%) patients were already anticoagulated and in five (7%) patients, anticoagulation had been stopped because of complications. Initial diagnosis of AF was made by the pacemaker in 17 patients (26% of 66; 2% of 728); four (6% of 66) patients were newly initiated on anticoagulation. Of the 66 patients, 17 patients were already on AADs; 49 (74%) had satisfactory rate control or had other issues; only two (3% of 66; 0.3% of 728) received new AADs. Of 728 patients with DDD pacemakers, only 17 were newly discovered to have AF, and six (0.8%) had changes in medications based on the pacemaker data. Adding pacemaker-derived data to existing clinical information had little therapeutic impact, due to a combination of cumbersome workflow, and because AF was usually known to practitioners. Developments in automated monitoring systems may provide more accessible and therapeutically useful information. ©2014 Wiley Periodicals, Inc.

  12. Bipolar Disorder and Obsessive Compulsive Disorder Comorbidity

    Directory of Open Access Journals (Sweden)

    Necla Keskin

    2014-08-01

    Full Text Available The comorbidity of bipolar disorder and anxiety disorders is a well known concept. Obsessive-compulsive disorder is the most commonly seen comorbid anxiety disorder in bipolar patients. Some genetic variants, neurotransmitters especially serotonergic systems and second-messenger systems are thought to be responsible for its etiology. Bipolar disorder alters the clinical aspects of obsessive compulsive disorder and is associated with poorer outcome. The determination of comorbidity between bipolar disorder and obsessive compulsive disorder is quite important for appropriate clinical management and treatment. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 429-437

  13. Prefronto–cerebellar transcranial direct current stimulation improves visuospatial memory, executive functions, and neurological soft signs in patients with euthymic bipolar disorder

    Directory of Open Access Journals (Sweden)

    Minichino A

    2015-08-01

    Full Text Available Amedeo Minichino, Francesco Saverio Bersani, Laura Bernabei, Francesco Spagnoli, Lucilla Vergnani, Alessandra Corrado, Ines Taddei, Massimo Biondi, Roberto Delle Chiaie Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy Objective: The aim of the study was to improve neuropsychological functioning of euthymic patients with bipolar disorder (BD using transcranial direct current stimulation (tDCS applied to cerebellar and prefrontal cortices.Methods: Twenty-five BD outpatients underwent prefrontal (anodal and cerebellar (cathodal tDCS for 3 consecutive weeks. All participants were assessed through the Rey Complex Figure Test delay and copy and the Neurological Examination Scale at baseline and after therapy with tDCS.Results: After tDCS treatment, patients showed significant improvements in visuospatial memory tasks. Patients with worse baseline cognitive performances also showed a significant improvement in executive functioning tasks. Neurological Examination Scale total score and motor coordination subscale significantly improved.Conclusion: Prefrontal-excitatory and cerebellar-inhibitory stimulations in euthymic BD patients may lead to better neurocognitive performances. This improvement could result from the modulation of prefronto–thalamic–cerebellar circuit activity pattern, which can be disrupted in BD. Keywords: cerebellum, dorsolateral prefrontal cortex, neuropsychology, cognition 

  14. Influence of the Dermis Thickness on the Results of the Skin Treatment with Monopolar and Bipolar Radiofrequency Currents.

    Science.gov (United States)

    Kruglikov, Ilja L

    2016-01-01

    Electrically layered tissue structure significantly modifies distribution of radiofrequency (RF) current in the dermis and in the subcutaneous adipose tissue comparing to that in a homogeneous medium. On the basis of the simple model of RF current distribution in a two-layer skin containing dermis and subcutis, we assess the influence of the dermal thickness on the current density in different skin layers. Under other equal conditions, current density in the dermis is higher for the skin having thinner dermis. This contradicts the main paradigm of the RF theory stating that treatment results are mainly dependent on the maximal temperature reached in a target tissue, since the best short- and long-term clinical results of RF application to the skin were reported in the areas having thicker dermis. To resolve this contradiction, it is proposed that the long-term effect of RF can be realized through a structural modification of the subcutaneous fat depot adjacent to the treated skin area. Stimulation of these cells located near the interface dermis/subcutis will demand the concentration of applied RF energy in this area and will require the optimal arrangement of RF electrodes on the skin surface.

  15. Influence of the Dermis Thickness on the Results of the Skin Treatment with Monopolar and Bipolar Radiofrequency Currents

    Directory of Open Access Journals (Sweden)

    Ilja L. Kruglikov

    2016-01-01

    Full Text Available Electrically layered tissue structure significantly modifies distribution of radiofrequency (RF current in the dermis and in the subcutaneous adipose tissue comparing to that in a homogeneous medium. On the basis of the simple model of RF current distribution in a two-layer skin containing dermis and subcutis, we assess the influence of the dermal thickness on the current density in different skin layers. Under other equal conditions, current density in the dermis is higher for the skin having thinner dermis. This contradicts the main paradigm of the RF theory stating that treatment results are mainly dependent on the maximal temperature reached in a target tissue, since the best short- and long-term clinical results of RF application to the skin were reported in the areas having thicker dermis. To resolve this contradiction, it is proposed that the long-term effect of RF can be realized through a structural modification of the subcutaneous fat depot adjacent to the treated skin area. Stimulation of these cells located near the interface dermis/subcutis will demand the concentration of applied RF energy in this area and will require the optimal arrangement of RF electrodes on the skin surface.

  16. Modeling suicide in bipolar disorders.

    Science.gov (United States)

    Malhi, Gin S; Outhred, Tim; Das, Pritha; Morris, Grace; Hamilton, Amber; Mannie, Zola

    2018-02-19

    Suicide is a multicausal human behavior, with devastating and immensely distressing consequences. Its prevalence is estimated to be 20-30 times greater in patients with bipolar disorders than in the general population. The burden of suicide and its high prevalence in bipolar disorders make it imperative that our current understanding be improved to facilitate prediction of suicide and its prevention. In this review, we provide a new perspective on the process of suicide in bipolar disorder, in the form of a novel integrated model that is derived from extant knowledge and recent evidence. A literature search of articles on suicide in bipolar disorder was conducted in recognized databases such as Scopus, PubMed, and PsycINFO using the keywords "suicide", "suicide in bipolar disorders", "suicide process", "suicide risk", "neurobiology of suicide" and "suicide models". Bibliographies of identified articles were further scrutinized for papers and book chapters of relevance. Risk factors for suicide in bipolar disorders are well described, and provide a basis for a framework of epigenetic mechanisms, moderated by neurobiological substrates, neurocognitive functioning, and social inferences within the environment. Relevant models and theories include the diathesis-stress model, the bipolar model of suicide and the ideation-to-action models, the interpersonal theory of suicide, the integrated motivational-volitional model, and the three-step theory. Together, these models provide a basis for the generation of an integrated model that illuminates the suicidal process, from ideation to action. Suicide is complex, and it is evident that a multidimensional and integrated approach is required to reduce its prevalence. The proposed model exposes and provides access to components of the suicide process that are potentially measurable and may serve as novel and specific therapeutic targets for interventions in the context of bipolar disorder. Thus, this model is useful not only

  17. Aggregatibacter aphrophilus pacemaker endocarditis: a case report.

    Science.gov (United States)

    Patel, Sahil R; Patel, Nishi H; Borah, Amit; Saltzman, Heath

    2014-12-08

    Aggregatibacter bacteria are a rare cause of endocarditis in adults. They are part of a group of organisms known as HACEK--Haemophilus, Aggregatibacter, Cardiobacter, Eikenella, and Kingella. Among these organisms, several Haemophilus species have been reclassified under the genus Aggregatibacter. Very few cases of Aggregatibacter endocarditis in patients with pacemaker devices have been reported. We present here what we believe to be the first case of Aggregatibacter aphrophilus pacemaker endocarditis. A 62-year-old African American male with a medical history significant for dual-chamber pacemaker placement in 1996 for complete heart block with subsequent lead manipulation in 2007, presented to his primary care doctor with fever, chills, night sweats, fatigue, and ten-pound weight loss over a four-month period. Physical examination revealed a new murmur and jugular venous distension which prompted initiation of antibiotics for suspicion of endocarditis. Both sets of initial blood cultures were positive for A. aphrophilus. Transesophageal echocardiogram revealed vegetations on the tricuspid valve and the right ventricular pacemaker lead (Figure 1). This case highlights the importance of identifying rare causes of endocarditis and recognizing that treatment may not differ from the standard treatment for typical presentations. The patient received intravenous ceftriaxone for his endocarditis for a total of six weeks. Upon device removal, temporary jugular venous pacing wires were placed. After two weeks of antibiotic treatment and no clinical deterioration, a new permanent pacemaker was placed and the patient was discharged home. This is the first case of A. aphrophilus endocarditis in a patient with a permanent pacemaker. Our patient had no obvious risk factors other than poor dentition and a history of repeated pacemaker lead manipulation. This suggests that valvulopathies secondary to repeated lead manipulation can be clinically significant factors in morbidity

  18. High-pass filtering of input signals by the Ih current in a non-spiking neuron, the retinal rod bipolar cell.

    Directory of Open Access Journals (Sweden)

    Lorenzo Cangiano

    Full Text Available Hyperpolarization-activated cyclic nucleotide-sensitive (HCN channels mediate the I(f current in heart and I(h throughout the nervous system. In spiking neurons I(h participates primarily in different forms of rhythmic activity. Little is known, however, about its role in neurons operating with graded potentials as in the retina, where all four channel isoforms are expressed. Intriguing evidence for an involvement of I(h in early visual processing are the side effects reported, in dim light or darkness, by cardiac patients treated with HCN inhibitors. Moreover, electroretinographic recordings indicate that these drugs affect temporal processing in the outer retina. Here we analyzed the functional role of HCN channels in rod bipolar cells (RBCs of the mouse. Perforated-patch recordings in the dark-adapted slice found that RBCs exhibit I(h, and that this is sensitive to the specific blocker ZD7288. RBC input impedance, explored by sinusoidal frequency-modulated current stimuli (0.1-30 Hz, displays band-pass behavior in the range of I(h activation. Theoretical modeling and pharmacological blockade demonstrate that high-pass filtering of input signals by I(h, in combination with low-pass filtering by passive properties, fully accounts for this frequency-tuning. Correcting for the depolarization introduced by shunting through the pipette-membrane seal, leads to predict that in darkness I(h is tonically active in RBCs and quickens their responses to dim light stimuli. Immunohistochemistry targeting candidate subunit isoforms HCN1-2, in combination with markers of RBCs (PKC and rod-RBC synaptic contacts (bassoon, mGluR6, Kv1.3, suggests that RBCs express HCN2 on the tip of their dendrites. The functional properties conferred by I(h onto RBCs may contribute to shape the retina's light response and explain the visual side effects of HCN inhibitors.

  19. Pacemaker patients’ perspective and experiences in a pacemaker outpatient clinic in relation to test intervals of the pacemaker

    DEFF Research Database (Denmark)

    Lauberg, Astrid; Hansen, Tina; Pedersen, Trine Pernille Dahl

    an evident decline in quality of life regarding psychological and social aspects 6 month after the implantation in terms of cognitive function, work ability, and sexual activity. Mlynarski et al (2009) have found correlations between pacemaker implantation and anxiety and depression. Aim The aim...... the pacemaker and psychological reactions. Patients with pacemakers older than 3 months lacked communication with fellowmen. Conclusion The patients express receiving competent and professional treatment when visiting the outpatient clinic, there seems to be a discrepancy between the long test intervals...... and the critical period in which anxiety and depression may occur. Minor problems and questions may grow into fatal conditions if the patients are not offered an opportunity to discuss this with experts. Patients are not informed that it is possible to discuss problems that imply psychological topics and they do...

  20. Synchronization of Coupled Neurons Controlled by a Pacemaker

    International Nuclear Information System (INIS)

    Li Mei-Sheng; Zhang Hong-Hui; Zhao Yong; Shi Xia

    2011-01-01

    We investigate synchronization of Hindmarsh—Rose neurons with gap junctions under the control of a pacemaker. In a ring Hindmarsh—Rose neuronal network, the coupled neurons with the pacemaker can occur in synchronization more easily than those without the pacemaker. Furthermore, the pacemaker can induce phase synchronization or nearly-complete synchronization of nonidentical neurons. This synchronization can occur more easily when time delay is considered. Theses results can be helpful to understand the activities of the real neuronal system. (general)

  1. Integrated neurobiology of bipolar disorder

    Directory of Open Access Journals (Sweden)

    Vladimir eMaletic

    2014-08-01

    Full Text Available From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity—reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition—limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional unified field theory of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial-neuronal interactions. Among these glial elements are microglia—the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the HPA axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the great

  2. Spanish Pacemaker Registry. Twelfth Official Report of the Spanish Society of Cardiology Working Group on Cardiac Pacing (2014).

    Science.gov (United States)

    Cano Pérez, Óscar; Pombo Jiménez, Marta; Coma Samartín, Raúl

    2015-12-01

    This report describes the results of the analysis of pacemaker implant and replacement data submitted to the Spanish Pacemaker Registry in 2014, with special reference to pacing mode selection. The report is based on the processing of information provided by the European Pacemaker Patient Identification Card. Information was received from 117 hospitals, with a total of 12 358 cards, representing 34% of estimated activity. Use of conventional generators and resynchronization devices was 784 and 64.4 units per million population, respectively. The mean age of patients receiving an implant was 77.3 years. Men received 59% of implants and 56.4% of replacements. Most patients receiving generator implants and replacements were in the age range 80 to 89 years. Most endocardial leads used were bipolar, and 84.2% had an active fixation system. Pacing was in VVI/R mode despite being in sinus rhythm in 24.7% of patients with sick sinus syndrome and 24% of those with atrioventricular block. The use of pacemaker generators and resynchronization devices per million population continued to increase. Most implanted leads had active fixation and approximately 20% had magnetic resonance imaging protection. Age and sex directly influenced pacing mode selection, which could have been improved in more than 20% of cases. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  3. Setups for in vitro assessment of RFID interference on pacemakers

    International Nuclear Information System (INIS)

    Mattei, E; Censi, F; Delogu, A; Ferrara, A; Calcagnini, G

    2013-01-01

    The aim of this study is to propose setups for in vitro assessment of RFID (radiofrequency identification) interference on pacemakers (PM). The voltage induced at the input stage of the PM by low-frequency (LF) and high-frequency (HF) RFID transmitters has been used to quantify the amount of the interference. A commercial PM was modified in order to measure the voltage at its input stage when exposed to a sinusoidal signal at 125 kHz and 13.56 MHz. At both frequencies, two antennas with different dimensions (diameter = 10 cm and 30 cm, respectively) were used to generate the interfering field, and the induced voltage was measured between the lead tip and the PM case (unipolar voltage), and between the tip and ring electrodes (bipolar voltage). The typical lead configurations adopted in similar studies or proposed by international standards, as well as lead paths closer to actual physiological implants were tested. At 125 kHz, the worst-case condition differs for the two antennas: the 10 cm antenna induced the highest voltage in the two-loop spiral configuration, whereas the 30 cm antenna in the 225 cm 2 loop configuration. At 13.56 MHz, the highest voltage was observed for both the antennas in the 225 cm 2 loop configuration. Bipolar voltages were found to be lower than the unipolar voltages induced in the same configurations, this difference being not as high as one could expect from theoretical considerations. The worst-case scenario, in terms of the induced voltage at the PM input stage, has been identified both for LF and HF readers, and for two sizes of transmitting antennas. These findings may provide the basis for the definition of a standard implant configuration and a lead path to test the EMI effects of LF and HF RFID transmitters on active implantable devices. (paper)

  4. Toward a complex system understanding of bipolar disorder: A chaotic model of abnormal circadian activity rhythms in euthymic bipolar disorder.

    Science.gov (United States)

    Hadaeghi, Fatemeh; Hashemi Golpayegani, Mohammad Reza; Jafari, Sajad; Murray, Greg

    2016-08-01

    In the absence of a comprehensive neural model to explain the underlying mechanisms of disturbed circadian function in bipolar disorder, mathematical modeling is a helpful tool. Here, circadian activity as a response to exogenous daily cycles is proposed to be the product of interactions between neuronal networks in cortical (cognitive processing) and subcortical (pacemaker) areas of the brain. To investigate the dynamical aspects of the link between disturbed circadian activity rhythms and abnormalities of neurotransmitter functioning in frontal areas of the brain, we developed a novel mathematical model of a chaotic system which represents fluctuations in circadian activity in bipolar disorder as changes in the model's parameters. A novel map-based chaotic system was developed to capture disturbances in circadian activity across the two extreme mood states of bipolar disorder. The model uses chaos theory to characterize interplay between neurotransmitter functions and rhythm generation; it aims to illuminate key activity phenomenology in bipolar disorder, including prolonged sleep intervals, decreased total activity and attenuated amplitude of the diurnal activity rhythm. To test our new cortical-circadian mathematical model of bipolar disorder, we utilized previously collected locomotor activity data recorded from normal subjects and bipolar patients by wrist-worn actigraphs. All control parameters in the proposed model have an important role in replicating the different aspects of circadian activity rhythm generation in the brain. The model can successfully replicate deviations in sleep/wake time intervals corresponding to manic and depressive episodes of bipolar disorder, in which one of the excitatory or inhibitory pathways is abnormally dominant. Although neuroimaging research has strongly implicated a reciprocal interaction between cortical and subcortical regions as pathogenic in bipolar disorder, this is the first model to mathematically represent this

  5. 21 CFR 870.3730 - Pacemaker service tools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker service tools. 870.3730 Section 870.3730...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3730 Pacemaker service tools. (a) Identification. Pacemaker service tools are devices such as screwdrivers and Allen wrenches...

  6. 21 CFR 870.5550 - External transcutaneous cardiac pacemaker (noninvasive).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External transcutaneous cardiac pacemaker... § 870.5550 External transcutaneous cardiac pacemaker (noninvasive). (a) Identification. An external transcutaneous cardiac pacemaker (noninvasive) is a device used to supply a periodic electrical pulse intended to...

  7. 21 CFR 870.3610 - Implantable pacemaker pulse generator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Implantable pacemaker pulse generator. 870.3610 Section 870.3610 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... pacemaker pulse generator. (a) Identification. An implantable pacemaker pulse generator is a device that has...

  8. 21 CFR 870.3720 - Pacemaker electrode function tester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker electrode function tester. 870.3720... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3720 Pacemaker electrode function tester. (a) Identification. A pacemaker electrode function tester is a device which is...

  9. 21 CFR 870.3650 - Pacemaker polymeric mesh bag.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

  10. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker generator function analyzer. 870.3630... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3630 Pacemaker generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is...

  11. 21 CFR 870.3710 - Pacemaker repair or replacement material.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker repair or replacement material. 870.3710... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3710 Pacemaker repair or replacement material. (a) Identification. A pacemaker repair or replacement material is an...

  12. 21 CFR 870.1750 - External programmable pacemaker pulse generator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External programmable pacemaker pulse generator. 870.1750 Section 870.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... External programmable pacemaker pulse generator. (a) Identification. An external programmable pacemaker...

  13. Analysis of a five year experience of permanent pacemaker ...

    African Journals Online (AJOL)

    Introduction: Permanent pacemaker implantation is available in Nigeria. There is however no national registry or framework for pacemaker data collection. A pacemaker database has been developed in our institution and the results are analyzed in this study. Methods: The study period was between January 2008 and ...

  14. Wenckebach upper rate response in single chamber pacemaker.

    Science.gov (United States)

    Barold, S S

    2000-07-01

    The Medtronic Minix pacemaker during normal function in the VVT mode was found to exhibit a Wenckenbach upper rate response similar to that of dual chamber devices. This behavior occurred only when the upper rate interval was longer than the pacemaker refractory period. In a single chamber device this response may simulate pacemaker malfunction.

  15. 21 CFR 870.3690 - Pacemaker test magnet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker test magnet. 870.3690 Section 870.3690...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3690 Pacemaker test magnet. (a) Identification. A pacemaker test magnet is a device used to test an inhibited or triggered type...

  16. Uniform pacemaker and ICD information system in the Netherlands

    NARCIS (Netherlands)

    Cam, H; Wa, D; Callaos, N; Farsi, D; EshaghianWilner, M; Hanratty, T; Rishe, N

    2003-01-01

    The Central Pacemaker Patient Registry (CPPR) in the Netherlands (founded in 1977) collects information of pacemaker patients from all 110 Dutch hospitals. It contains data of over 98.000 patients, 118.500 pacemakers, 1.950 ICD's and 131.000 leads. Initially data was entered manually. As local

  17. The pacemaker-twiddler's syndrome: an infrequent cause of pacemaker failure.

    Science.gov (United States)

    Salahuddin, Mohammad; Cader, Fathima Aaysha; Nasrin, Sahela; Chowdhury, Mashhud Zia

    2016-01-20

    The pacemaker-twiddler's syndrome is an uncommon cause of pacemaker malfunction. It occurs due to unintentional or deliberate manipulation of the pacemaker pulse generator within its skin pocket by the patient. This causes coiling of the lead and its dislodgement, resulting in failure of ventricular pacing. More commonly reported among elderly females with impaired cognition, the phenomenon usually occurs in the first year following pacemaker implantation. Treatment involves repositioning of the dislodged leads and suture fixation of the lead and pulse generator within its pocket. An 87 year old Bangladeshi lady who underwent a single chamber ventricular pacemaker (VVI mode: i.e. ventricle paced, ventricle sensed, inhibitory mode) implantation with the indication of complete heart block, and presented to us again 7 weeks later, with syncopal attacks. She admitted to repeatedly manipulating the pacemaker generator in her left pectoral region. Physical examination revealed a heart rate of 42 beats/minute, blood pressure 140/80 mmHg and bilateral crackles on lung auscultation. She had no cognitive deficit. An immediate electrocardiogram showed complete heart block with pacemaker spikes and failure to capture. Chest X-ray showed coiled and retracted right ventricular lead and rotated pulse generator. An emergent temporary pace maker was set at a rate of 60 beats per minute. Subsequently, she underwent successful lead repositioning with strong counselling to avoid further twiddling. Twiddler's syndrome should be considered as a cause of pacemaker failure in elderly patients presenting with bradyarrythmias following pacemaker implantation. Chest X-ray and electrocardiograms are simple and easily-available first line investigations for its diagnosis. Lead repositioning is required, however proper patient education and counselling against further manipulation is paramount to long-term management.

  18. Electromagnetic and radiation environments: effects on pacemakers

    International Nuclear Information System (INIS)

    Mouton, J.; Trochet, R.; Vicrey, J.; Sauvage, M.; Chauvenet, B.; Ostrovski, A.; Leroy, E.; Haug, R.; Dodinot, B.; Joffre, F.

    1999-01-01

    Nowadays, medical care development allows many people to share the benefits of implanted pacemakers (PM). PM can be perturbed and even fall in complete breakdowns in an electromagnetic and radiation environment. A stimuli-dependent patient can thus be seriously in danger. This article presents the effect of ionizing radiation from either a cobalt-60 source or from a linear accelerator (Saturne 43) on 12 pacemakers. It seems that technological progress make electronic circuits more sensitive to the cumulated dose of radiation. This survey shows that pacemakers have great difficulties to sustain ionizing radiation doses that are commonly delivered to patients during therapies. Usually perturbed functioning appears suddenly and means a strong shift of stimuli that might lead to heart failure

  19. Quetiapine monotherapy for bipolar depression

    Directory of Open Access Journals (Sweden)

    Michael E Thase

    2008-03-01

    Full Text Available Michael E ThaseDepartments of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA; the Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA; and the University of Pittsburgh Medical Center, Pittsburgh, PA, USAAbstract: Bipolar depression is more common, disabling, and difficult-to-treat than the manic and hypomanic phases that define bipolar disorder. Unlike the treatment of so-called “unipolar” depressions, antidepressants generally are not indicated as monotherapies for bipolar depressions and recent studies suggest that - even when used in combination with traditional mood stabilizers – antidepressants may have questionable value for bipolar depression. The current practice is that mood stabilizers are initiated first as monotherapies; however, the antidepressant efficacy of lithium and valproate is modest at best. Within this context the role of atypical antipsychotics is being evaluated. The combination of olanzapine and the antidepressant fluoxetine was the first treatment to receive regulatory approval in the US specifically for bipolar I depression. Quetiapine was the second medication to be approved for this indication, largely as the result of two pivotal trials known by the acronyms of BOLDER (BipOLar DEpRession I and II. Both studies demonstrated that two doses of quetiapine (300 mg and 600 mg given once daily at bedtime were significantly more effective than placebo, with no increased risk of patients switching into mania. Pooling the two studies, quetiapine was effective for both bipolar I and bipolar II depressions and for patients with (and without a history of rapid cycling. The two doses were comparably effective in both studies. Although the efficacy of quetiapine monotherapy has been established, much additional research is necessary. Further studies are needed to more fully investigate dose-response relationships and comparing quetiapine monotherapy to other mood stabilizers

  20. Analysis of Cumulative Dose to Implanted Pacemaker According to Various IMRT Delivery Methods: Optimal Dose Delivery Versus Dose Reduction Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Woo; Hong, Se Mie [Dept. of Radiation Oncology, Konkuk University Medical Center, Seoul (Korea, Republic of)

    2011-11-15

    Cancer patients with implanted cardiac pacemaker occasionally require radiotherapy. Pacemaker may be damaged or malfunction during radiotherapy due to ionizing radiation or electromagnetic interference. Although radiotherapy should be planned to keep the dose to pacemaker as low as possible not to malfunction ideally, current radiation treatment planning (RTP) system does not accurately calculate deposited dose to adjacent field border or area beyond irradiated fields. In terms of beam delivery techniques using multiple intensity modulated fields, dosimetric effect of scattered radiation in high energy photon beams is required to be detailed analyzed based on measurement data. The aim of this study is to evaluate dose discrepancies of pacemaker in a RTP system as compared to measured doses. We also designed dose reduction strategy limited value of 2 Gy for radiation treatment patients with cardiac implanted pacemaker. Total accumulated dose of 145 cGy based on in-vivo dosimetry was satisfied with the recommendation criteria to prevent malfunction of pacemaker in SS technique. However, the 2 mm lead shielder enabled the scattered doses to reduce up to 60% and 40% in the patient and the phantom, respectively. The SS technique with the lead shielding could reduce the accumulated scattered doses less than 100 cGy. Calculated and measured doses were not greatly affected by the beam delivery techniques. In-vivo and measured doses on pacemaker position showed critical dose discrepancies reaching up to 4 times as compared to planned doses in RTP. The current SS technique could deliver lower scattered doses than recommendation criteria, but use of 2 mm lead shielder contributed to reduce scattered doses by 60%. The tertiary lead shielder can be useful to prevent malfunction or electrical damage of implanted pacemakers during radiotherapy. It is required to estimate more accurate scattered doses of the patient or medical device in RTP to design proper dose reduction strategy.

  1. Analysis of Cumulative Dose to Implanted Pacemaker According to Various IMRT Delivery Methods: Optimal Dose Delivery Versus Dose Reduction Strategy

    International Nuclear Information System (INIS)

    Lee, Jeong Woo; Hong, Se Mie

    2011-01-01

    Cancer patients with implanted cardiac pacemaker occasionally require radiotherapy. Pacemaker may be damaged or malfunction during radiotherapy due to ionizing radiation or electromagnetic interference. Although radiotherapy should be planned to keep the dose to pacemaker as low as possible not to malfunction ideally, current radiation treatment planning (RTP) system does not accurately calculate deposited dose to adjacent field border or area beyond irradiated fields. In terms of beam delivery techniques using multiple intensity modulated fields, dosimetric effect of scattered radiation in high energy photon beams is required to be detailed analyzed based on measurement data. The aim of this study is to evaluate dose discrepancies of pacemaker in a RTP system as compared to measured doses. We also designed dose reduction strategy limited value of 2 Gy for radiation treatment patients with cardiac implanted pacemaker. Total accumulated dose of 145 cGy based on in-vivo dosimetry was satisfied with the recommendation criteria to prevent malfunction of pacemaker in SS technique. However, the 2 mm lead shielder enabled the scattered doses to reduce up to 60% and 40% in the patient and the phantom, respectively. The SS technique with the lead shielding could reduce the accumulated scattered doses less than 100 cGy. Calculated and measured doses were not greatly affected by the beam delivery techniques. In-vivo and measured doses on pacemaker position showed critical dose discrepancies reaching up to 4 times as compared to planned doses in RTP. The current SS technique could deliver lower scattered doses than recommendation criteria, but use of 2 mm lead shielder contributed to reduce scattered doses by 60%. The tertiary lead shielder can be useful to prevent malfunction or electrical damage of implanted pacemakers during radiotherapy. It is required to estimate more accurate scattered doses of the patient or medical device in RTP to design proper dose reduction strategy.

  2. Nuclear-powered pacemaker fuel cladding study

    International Nuclear Information System (INIS)

    Shoup, R.L.

    1976-07-01

    The fabrication of fuel capsules with refractory metal and alloy clads used in nuclear-powered cardiac pacemakers precludes the expedient dissolution of the clad in inorganic acid solutions. An experiment to measure penetration rates of acids on commonly used fuel pellet clads indicated that it is not impossible, but that it would be very difficult to dissolve the multiple cladding. This work was performed because of a suggestion that a 238 PuO 2 -powered pacemaker could be transformed into a terrorism weapon

  3. The influence of radiation therapy on cardiac pacemakers

    International Nuclear Information System (INIS)

    Coles, J.R.; Ciddor, G.S.

    1980-01-01

    The results of an investigation to determine the influence on pacemaking of ionizing radiation and electromagnetic radiation from a number of radiotherapy machines are reported. In vitro tests were carried out on unipolar cardiac pacemakers of the ventricular inhibited type. The pacemakers were largely unaffected by the environment of clinical radiotherapy machines. Ionizing radiation had no detrimental effect on the pacemakers and electromagnetic interference caused only temporary single-beat inhibition at most. With the betatron used, malfunction of the pacemakers regularly occurred whilst in their inhibited made of operation. The demand function became disabled allowing competitive asynchronous pulses to be produced

  4. Bipolar disorder in adolescence.

    Science.gov (United States)

    DeFilippis, Melissa; Wagner, Karen Dineen

    2013-08-01

    Bipolar disorder is a serious psychiatric condition that may have onset in childhood. It is important for physicians to recognize the symptoms of bipolar disorder in children and adolescents in order to accurately diagnose this illness early in its course. Evidence regarding the efficacy of various treatments is necessary to guide the management of bipolar disorder in youth. For example, several medications commonly used for adults with bipolar disorder have not shown efficacy for children and adolescents with bipolar disorder. This article reviews the prevalence, diagnosis, course, and treatment of bipolar disorder in children and adolescents and provides physicians with information that will aid in diagnosis and treatment.

  5. Biventricular pacemaker implantation with the BV Pulsera

    Energy Technology Data Exchange (ETDEWEB)

    Wright, J.D.W.; Todd, D.; Waktare, J.E.P.; Hughes, S.; Abell, C. [The Cardiothoracic Centre, Liverpool (United Kingdom)

    2005-07-01

    The BV Pulsera mobile X-ray system is used for biventricular pacemaker implantation in a surgical environment. It provides high-quality images of the moving structures, including the fine coronary leads, and can be used for long fluoroscopy runs without overheating. (orig.)

  6. Biventricular pacemaker implantation with the BV Pulsera

    International Nuclear Information System (INIS)

    Wright, J.D.W.; Todd, D.; Waktare, J.E.P.; Hughes, S.; Abell, C.

    2005-01-01

    The BV Pulsera mobile X-ray system is used for biventricular pacemaker implantation in a surgical environment. It provides high-quality images of the moving structures, including the fine coronary leads, and can be used for long fluoroscopy runs without overheating. (orig.)

  7. Keeping the Rhythm : Cardiac Pacemaker Cell Development

    NARCIS (Netherlands)

    Burkhard, S.B.

    2017-01-01

    The heart is the first organ to form and function in the developing vertebrate embryo. Its proper morphogenesis and function is crucial for survival. Here we focus on the development and characterization of a highly specialized subset of cardiac cells, the pacemaker cells. In the mammalian heart,

  8. Quality assessment of pacemaker implantations in Denmark

    DEFF Research Database (Denmark)

    Møller, M; Arnsbo, P; Asklund, Mogens

    2002-01-01

    AIMS: Quality assessment of therapeutic procedures is essential to insure a cost-effective health care system. Pacemaker implantation is a common procedure with more than 500,000 implantations world-wide per year, but the general complication rate is not well described. We studied procedure relat...

  9. Genetics of bipolar disorder

    Directory of Open Access Journals (Sweden)

    Kerner B

    2014-02-01

    Full Text Available Berit Kerner Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA Abstract: Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a “risk” allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders. In many Mendelian syndromes, psychiatric symptoms are prevalent. Although these conditions do not fit the classic description of any specific psychiatric disorder, they often show nonspecific psychiatric symptoms that cross diagnostic boundaries, including intellectual disability, behavioral abnormalities, mood disorders, anxiety disorders, attention deficit, impulse control deficit, and psychosis. Although testing for chromosomal disorders and monogenic Mendelian disorders is well established, testing for common variants is still controversial. The standard concept of genetic testing includes at least three broad criteria that need to be fulfilled before new genetic tests should be introduced: analytical validity, clinical validity, and clinical utility. These criteria are

  10. Measuring pacemaker dose: A clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Studenski, Matthew T., E-mail: matthew.studenski@jeffersonhospital.org [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Xiao Ying; Harrison, Amy S. [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2012-07-01

    Recently in our clinic, we have seen an increased number of patients presenting with pacemakers and defibrillators. Precautions are taken to develop a treatment plan that minimizes the dose to the pacemaker because of the adverse effects of radiation on the electronics. Here we analyze different dosimeters to determine which is the most accurate in measuring pacemaker or defibrillator dose while at the same time not requiring a significant investment in time to maintain an efficient workflow in the clinic. The dosimeters analyzed here were ion chambers, diodes, metal-oxide-semiconductor field effect transistor (MOSFETs), and optically stimulated luminescence (OSL) dosimeters. A simple phantom was used to quantify the angular and energy dependence of each dosimeter. Next, 8 patients plans were delivered to a Rando phantom with all the dosimeters located where the pacemaker would be, and the measurements were compared with the predicted dose. A cone beam computed tomography (CBCT) image was obtained to determine the dosimeter response in the kilovoltage energy range. In terms of the angular and energy dependence of the dosimeters, the ion chamber and diode were the most stable. For the clinical cases, all the dosimeters match relatively well with the predicted dose, although the ideal dosimeter to use is case dependent. The dosimeters, especially the MOSFETS, tend to be less accurate for the plans, with many lateral beams. Because of their efficiency, we recommend using a MOSFET or a diode to measure the dose. If a discrepancy is observed between the measured and expected dose (especially when the pacemaker to field edge is <10 cm), we recommend analyzing the treatment plan to see whether there are many lateral beams. Follow-up with another dosimeter rather than repeating multiple times with the same type of dosimeter. All dosimeters should be placed after the CBCT has been acquired.

  11. Modulation of Pacemaker Potentials in Murine Small Intestinal Interstitial Cells of Cajal by Gamisoyo-San, a Traditional Chinese Herbal Medicine.

    Science.gov (United States)

    Kim, Doeun; Kim, Jung Nam; Nam, Joo Hyun; Lee, Jong Rok; Kim, Sang Chan; Kim, Byung Joo

    2018-04-19

    The Gamisoyo-san (GSS) has been used for -improving the gastrointestinal (GI) symptoms. The purpose of this study was to investigate the effects of GSS, a traditional Chinese herbal medicine, on the pacemaker potentials of mouse small intestinal interstitial cells of Cajal (ICCs). ICCs from the small intestines were dissociated and cultured. Whole-cell patch-clamp configuration was used to record pacemaker potentials and membrane currents. GSS depolarized ICC pacemaker potentials in a dose-dependent manner. Pretreatment with 4-diphenylacetoxypiperidinium iodide completely inhibited GSS-induced pacemaker potential depolarizations. Intracellular GDP-β-S inhibited GSS-induced effects, and in the presence of U-73122, GSS-induced effects were inhibited. Also, GSS in the presence of a Ca2+-free solution or thapsigargin did not depolarize pacemaker potentials. However, in the presence of calphostin C, GSS slightly depolarized pacemaker potentials. Furthermore, GSS inhibited both transient receptor potential melastatin7 and Ca2+-activated Cl- channel (anoctamin1) currents. GSS depolarized pacemaker potentials of ICCs via G protein and muscarinic M3 receptor signaling pathways and through internal or external Ca2+-, phospholipase C-, and protein kinase C-dependent and transient receptor potential melastatin 7-, and anoctamin 1-independent pathways. The study shows that GSS may regulate GI tract motility, suggesting that GSS could be a basis for developing novel prokinetic agents for treating GI motility dysfunctions. © 2018 S. Karger AG, Basel.

  12. Pacemakers and implantable cardioverter defibrillators - general and anesthetic considerations

    Directory of Open Access Journals (Sweden)

    Amy G. Rapsang

    2014-06-01

    Full Text Available A pacemaking system consists of an impulse generator and lead or leads to carry the electrical impulse to the patient's heart. Pacemaker and implantable cardioverter defibrillator codes were made to describe the type of pacemaker or implantable cardioverter defibrillator implanted. Indications for pacing and implantable cardioverter defibrillator implantation were given by the American College of Cardiologists. Certain pacemakers have magnet-operated reed switches incorporated; however, magnet application can have serious adverse effects; hence, devices should be considered programmable unless known otherwise. When a device patient undergoes any procedure (with or without anesthesia, special precautions have to be observed including a focused history/physical examination, interrogation of pacemaker before and after the procedure, emergency drugs/temporary pacing and defibrillation, reprogramming of pacemaker and disabling certain pacemaker functions if required, monitoring of electrolyte and metabolic disturbance and avoiding certain drugs and equipments that can interfere with pacemaker function. If unanticipated device interactions are found, consider discontinuation of the procedure until the source of interference can be eliminated or managed and all corrective measures should be taken to ensure proper pacemaker function should be done. Post procedure, the cardiac rate and rhythm should be monitored continuously and emergency drugs and equipments should be kept ready and consultation with a cardiologist or a pacemaker-implantable cardioverter defibrillator service may be necessary.

  13. Mechanisms underlying the cardiac pacemaker: the role of SK4 calcium-activated potassium channels.

    Science.gov (United States)

    Weisbrod, David; Khun, Shiraz Haron; Bueno, Hanna; Peretz, Asher; Attali, Bernard

    2016-01-01

    The proper expression and function of the cardiac pacemaker is a critical feature of heart physiology. The sinoatrial node (SAN) in human right atrium generates an electrical stimulation approximately 70 times per minute, which propagates from a conductive network to the myocardium leading to chamber contractions during the systoles. Although the SAN and other nodal conductive structures were identified more than a century ago, the mechanisms involved in the generation of cardiac automaticity remain highly debated. In this short review, we survey the current data related to the development of the human cardiac conduction system and the various mechanisms that have been proposed to underlie the pacemaker activity. We also present the human embryonic stem cell-derived cardiomyocyte system, which is used as a model for studying the pacemaker. Finally, we describe our latest characterization of the previously unrecognized role of the SK4 Ca(2+)-activated K(+) channel conductance in pacemaker cells. By exquisitely balancing the inward currents during the diastolic depolarization, the SK4 channels appear to play a crucial role in human cardiac automaticity.

  14. Excitation model of pacemaker cardiomyocytes of cardiac conduction system

    Science.gov (United States)

    Grigoriev, M.; Babich, L.

    2015-11-01

    Myocardium includes typical and atypical cardiomyocytes - pacemakers, which form the cardiac conduction system. Excitation from the atrioventricular node in normal conditions is possible only in one direction. Retrograde direction of pulses is impossible. The most important prerequisite for the work of cardiomyocytes is the anatomical integrity of the conduction system. Changes in contractile force of the cardiomyocytes, which appear periodically, are due to two mechanisms of self-regulation - heterometric and homeometric. Graphic course of the excitation pulse propagation along the heart muscle more accurately reveals the understanding of the arrhythmia mechanism. These models have the ability to visualize the essence of excitation dynamics. However, they do not have the proper forecasting function for result estimation. Integrative mathematical model enables further investigation of general laws of the myocardium active behavior, allows for determination of the violation mechanism of electrical and contractile function of cardiomyocytes. Currently, there is no full understanding of the topography of pacemakers and ionic mechanisms. There is a need for the development of direction of mathematical modeling and comparative studies of the electrophysiological arrangement of cells of atrioventricular connection and ventricular conduction system.

  15. Nutrition and Bipolar Depression.

    Science.gov (United States)

    Beyer, John L; Payne, Martha E

    2016-03-01

    As with physical conditions, bipolar disorder is likely to be impacted by diet and nutrition. Patients with bipolar disorder have been noted to have relatively unhealthy diets, which may in part be the reason they also have an elevated risk of metabolic syndrome and obesity. An improvement in the quality of the diet should improve a bipolar patient's overall health risk profile, but it may also improve their psychiatric outcomes. New insights into biological dysfunctions that may be present in bipolar disorder have presented new theoretic frameworks for understanding the relationship between diet and bipolar disorder. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Troponin T elevation after permanent pacemaker implantation.

    Science.gov (United States)

    Chen, Xueying; Yu, Ziqing; Bai, Jin; Hu, Shulan; Wang, Wei; Qin, Shengmei; Wang, Jingfeng; Sun, Zhe; Su, Yangang; Ge, Junbo

    2017-08-01

    The objective of the study is to study the incidence, significance, and factors associated with cardiac troponin T (CTNT) elevation after pacemaker implantation. Three hundred seventy-four patients (104 single-chamber pacemakers or ICD, 243 dual-chamber pacemakers, and 27 cardiac resynchronization therapy/cardiac resynchronization therapy defibrillator) who had normal levels of CTNT at baseline and underwent implantation of a permanent pacemaker system were included in this study. Serum levels of CTNT were measured at baseline, 6 and 24 h after the implantation procedure. The median of CTNT levels increased from 0.012 ng/mL at baseline to 0.032 and 0.019 ng/mL at 6 and 24 h after the procedure, respectively (all p 0.09 ng/mL). After 1-year follow-up, the incidence of complications including dislodgement of the lead, pocket infection, pneumothorax, hemothorax, and vein thrombus and cardiac outcomes including hospitalization of heart failure, coronary artery disease, arrhythmia, and cardiovascular mortality was not significantly different between the normal and elevated CTNT groups at 6 h after the procedure. By logistic regression analysis, gender, N-terminal pro-B type natriuretic peptide (NT-pro-BNP) at baseline, left ventricular ejection fractions (LVEF), estimated glomerular filtration rate (eGFR), and fluoroscopy time were independently associated with CTNT elevation after adjusted for age, pacemaker types, right ventricle lead location (RVA or RVOT), heart function, and left ventricular end systolic dimension. Pacemaker implantation was found to be accompanied with CTNT elevation in 55.6% of the patients at 6 h after the procedure, and its kinetics were fast, which might not be related to the complications and adverse cardiac outcomes within 1 year of follow-up. Moreover, gender, NT-pro-BNP at baseline, LVEF, eGFR, and fluoroscopy time were found to be independent predictors of CTNT elevation.

  17. Eletrocirurgia: sistemas mono e bipolar em cirurgia videolaparoscópica

    Directory of Open Access Journals (Sweden)

    Manoel Roberto Maciel Trindade

    1998-07-01

    Full Text Available O conhecimento das leis físicas e dos mecanismos de funcionamento da eletrocirurgia são de grande importância para o cirurgião. Lesões por eletrocirurgia em laparoscopia têm sido observadas, e estão associadas ao uso do eletrodo monopolar, com freqüência de 1 a 2 lesões a cada 1000 procedimentos.Com relação ao desenvolvimento de lesão, existem vários fatores que influenciam: densidade da corrente; o tipo de onda e de coagulação usadas, com suas respectivas voltagens; as condições de isolamento dos dispositivos; a ocorrência do fenômeno de capacitância; e os riscos oferecidos pelo uso em pacientes com marcapasso. No sistema bipolar, a densidade de corrente encontrada ao redor de seus eletrodos é bem menor, levando a menos lesões e, ainda, elimina vários dos outros mecanismos lesivos, como a placa de retorno e os citados acima. Vários estudos demonstram, em colecistectomias, apendicectomias, polipectomias e outros, que o índice de complicações com o eletrodo bipolar é significativamente menor.the knowledge of the physical laws and of the mechanisms of functioning of electrosurgery are of great importance for the surgeon. Lesions caused by electrosurgery in laparoscopic procedures have been observed, and are associated with the use of monopolar electrode, with the frequency of 1 to 2 lesions in every 1000 procedures. Concerning the development of the lesions, several factors are involved; current density, the waveform and the type of coagulation used, with its respective voltages; the insulation condition of the devices; the occurrence of the phenomenon of capacitance and the risks involved with the use in patients with pacemakers. In bipolar electrosurgery, the current density produced around the electrodes is much lower, causing less tissue damage and, still, eliminating several of the other mechanims of injury, such as the dispersive electrode and those quoted above. Several studies reveal that the incidence of

  18. 76 FR 64223 - Cardiovascular Devices; Reclassification of External Pacemaker Pulse Generator Devices

    Science.gov (United States)

    2011-10-17

    ... Drug Administration 21 CFR Part 870 Cardiovascular Devices; Reclassification of External Pacemaker... Special Controls Guidance Document: External Pacemaker Pulse Generator; Availability; Proposed Rule and... [Docket No. FDA-2011-N-0650] Cardiovascular Devices; Reclassification of External Pacemaker Pulse...

  19. Neutron absorbed dose in a pacemaker CMOS

    International Nuclear Information System (INIS)

    Borja H, C. G.; Guzman G, K. A.; Valero L, C.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R.; Paredes G, L.

    2012-01-01

    The neutron spectrum and the absorbed dose in a Complementary Metal Oxide Semiconductor (CMOS), has been estimated using Monte Carlo methods. Eventually a person with a pacemaker becomes an oncology patient that must be treated in a linear accelerator. Pacemaker has integrated circuits as CMOS that are sensitive to intense and pulsed radiation fields. Above 7 MV therapeutic beam is contaminated with photoneutrons that could damage the CMOS. Here, the neutron spectrum and the absorbed dose in a CMOS cell was calculated, also the spectra were calculated in two point-like detectors in the room. Neutron spectrum in the CMOS cell shows a small peak between 0.1 to 1 MeV and a larger peak in the thermal region, joined by epithermal neutrons, same features were observed in the point-like detectors. The absorbed dose in the CMOS was 1.522 x 10 -17 Gy per neutron emitted by the source. (Author)

  20. Neutron absorbed dose in a pacemaker CMOS

    Energy Technology Data Exchange (ETDEWEB)

    Borja H, C. G.; Guzman G, K. A.; Valero L, C.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Paredes G, L., E-mail: fermineutron@yahoo.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-06-15

    The neutron spectrum and the absorbed dose in a Complementary Metal Oxide Semiconductor (CMOS), has been estimated using Monte Carlo methods. Eventually a person with a pacemaker becomes an oncology patient that must be treated in a linear accelerator. Pacemaker has integrated circuits as CMOS that are sensitive to intense and pulsed radiation fields. Above 7 MV therapeutic beam is contaminated with photoneutrons that could damage the CMOS. Here, the neutron spectrum and the absorbed dose in a CMOS cell was calculated, also the spectra were calculated in two point-like detectors in the room. Neutron spectrum in the CMOS cell shows a small peak between 0.1 to 1 MeV and a larger peak in the thermal region, joined by epithermal neutrons, same features were observed in the point-like detectors. The absorbed dose in the CMOS was 1.522 x 10{sup -17} Gy per neutron emitted by the source. (Author)

  1. Cardiac pacemaker dysfunction in children after thoracic drainage catheter manipulation.

    Science.gov (United States)

    Lobdell, K W; Walters, H L; Hudson, C; Hakimi, M

    1997-05-01

    Two children underwent placement of permanent, epicardial-lead, dual-chamber, unipolar pacemaker systems for complete heart block. Postoperatively, both patients demonstrated subcutaneous emphysema-in the area of their pulse generators-temporally related to thoracic catheter manipulation. Acutely, each situation was managed with manual compression of the pulse generator, ascertaining appropriate pacemaker sensing and pacing. Maintenance of compression with pressure dressings, vigilant observation/monitoring, and education of the care givers resulted in satisfactory pacemaker function without invasive intervention.

  2. Pacemaker lead erosion simulating "Loch Ness Monster": conservative management.

    Science.gov (United States)

    Garg, Naveen; Moorthy, Nagaraja

    2012-12-01

    The majority of pacemaker pocket or lead erosions are due to either mechanical erosion by the bulky pulse generator or secondary to pacemaker pocket infection. We describe an unusual case of delayed pacemaker lead erosion causing extrusion of a portion of the pacing lead, with separate entry and exit points, with the gap filled with new skin formation, simulating the "Loch Ness Monster", which was successfully managed conservatively by surgical reinsertion.

  3. Cardiac pacemaker and its production methods

    International Nuclear Information System (INIS)

    Purdy, D.L.; Speicher, V.; Shipko, F.J.; Johnson, W.L.

    1977-01-01

    The construction method of the cardiac pacemakers proposes to arrange the impulse machine and the battery between two container halves, to weld the container halves with the help of a laser beam under a protective atmosphere and finally to inject polyurethane foam through an orifice into the form. There is also the possibility to embed the impulse machine and the battery first into the polyurethane foam and afterwards to close both container halves. Titanium is a suitable material for the container. (DG) [de

  4. Leadless cardiac pacemakers: present and the future.

    Science.gov (United States)

    Chew, Derek S; Kuriachan, Vikas

    2018-01-01

    Pacing technology for many decades has been composed of a generator attached to leads that are usually transvenous. Recently, leadless pacemakers have been studied in clinical settings and now available for use in many countries. This includes the single-component Nanostim Leadless Cardiac Pacemaker and Micra Transcatheter Pacing System, as well as the multicomponent Wireless Stimulation Endocardial system. Clinical studies in single-component leadless pacing technology has shown that they can be successfully implanted with minimal complications. The follow-up studies also seem to confirm the findings from the initial clinical trials. These systems offer some advantages over a traditional pacing system comprised of a subcutaneous generator and transvenous leads. In many ways, these leadless systems are disruptive technologies that are changing the traditional pacemaker concept and preferred for some patients. Ongoing research is needed to better assess their long-term function, safety, and end-of-life strategies. In the future, multichamber leadless pacing is expected to be developed and perhaps obviating the need for transvenous leads and their associated complications.

  5. Pacemaker therapy in low-birth-weight infants.

    Science.gov (United States)

    Fuchigami, Tai; Nishioka, Masahiko; Akashige, Toru; Shimabukuro, Atsuya; Nagata, Nobuhiro

    2018-02-01

    Infants born with complete atrioventricular block (CAVB) and fetal bradycardia are frequently born with low birth weight. Three low-birth-weight CAVB infants underwent temporary pacemaker implantation, followed by permanent single-chamber pacemaker implantation at median body weights of 1.7 and 3.2 kg, respectively. All infants caught up with their growth curves and had >3 years of estimated residual battery life. This two-stage strategy was successful in facilitating permanent pacemaker implantation in low-birth-weight babies. Placement of single-chamber pacemaker on the apex of the left ventricle appears to be associated with longer battery lifespan. © 2018 Wiley Periodicals, Inc.

  6. Enhanced low dose rate radiation effect test on typical bipolar devices

    International Nuclear Information System (INIS)

    Liu Minbo; Chen Wei; Yao Zhibin; He Baoping; Huang Shaoyan; Sheng Jiangkun; Xiao Zhigang; Wang Zujun

    2014-01-01

    Two types of bipolar transistors and nine types bipolar integrated circuit were selected in the irradiation experiment at different "6"0Co γ dose rate. The base current of bipolar transistor and input bias current of amplifier and comparator was measured, low dose enhance factor of test device was obtained. The results show that bipolar device have enhanced low dose rate sensitivity, enhancement factor of bipolar integrated circuit was bigger than that of transistor, and enhanced low dose rate sensitivity greatly varied with different structure and process of bipolar device. (authors)

  7. The rationale and design of the Micra Transcatheter Pacing Study: safety and efficacy of a novel miniaturized pacemaker.

    Science.gov (United States)

    Ritter, Philippe; Duray, Gabor Z; Zhang, Shu; Narasimhan, Calambur; Soejima, Kyoko; Omar, Razali; Laager, Verla; Stromberg, Kurt; Williams, Eric; Reynolds, Dwight

    2015-05-01

    Recent advances in miniaturization technologies and battery chemistries have made it possible to develop a pacemaker small enough to implant within the heart while still aiming to provide similar battery longevity to conventional pacemakers. The Micra Transcatheter Pacing System is a miniaturized single-chamber pacemaker system that is delivered via catheter through the femoral vein. The pacemaker is implanted directly inside the right ventricle of the heart, eliminating the need for a device pocket and insertion of a pacing lead, thereby potentially avoiding some of the complications associated with traditional pacing systems. The Micra Transcatheter Pacing Study is currently undergoing evaluation in a prospective, multi-site, single-arm study. Approximately 720 patients will be implanted at up to 70 centres around the world. The study is designed to have a continuously growing body of evidence and data analyses are planned at various time points. The primary safety and efficacy objectives at 6-month post-implant are to demonstrate that (i) the percentage of Micra patients free from major complications related to the Micra system or implant procedure is significantly higher than 83% and (ii) the percentage of Micra patients with both low and stable thresholds is significantly higher than 80%. The safety performance benchmark is based on a reference dataset of 977 subjects from 6 recent pacemaker studies. The Micra Transcatheter Pacing Study will assess the safety and efficacy of a miniaturized, totally endocardial pacemaker in patients with an indication for implantation of a single-chamber ventricular pacemaker. NCT02004873. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  8. Integrated Neurobiology of Bipolar Disorder

    Science.gov (United States)

    Maletic, Vladimir; Raison, Charles

    2014-01-01

    From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity – reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition – limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional “unified field theory” of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial–neuronal interactions. Among these glial elements are microglia – the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic–pituitary–adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of

  9. 76 FR 53851 - Effective Date of Requirement for Premarket Approval for Cardiovascular Permanent Pacemaker...

    Science.gov (United States)

    2011-08-30

    ... Pacemaker Electrode; Correction AGENCY: Food and Drug Administration, HHS. ACTION: Proposed rule; correction... preamendments device: Cardiovascular permanent pacemaker electrode. The document was published with an incorrect...

  10. Electronic monitoring in bipolar disorder.

    Science.gov (United States)

    Faurholt-Jepsen, Maria

    2018-03-01

    Major reasons for the insufficient effects of current treatment options in bipolar disorder include delayed intervention for prodromal depressive and manic symptoms and decreased adherence to psychopharmacological treatment. The reliance on subjective information and clinical evaluations when diagnosing and assessing the severity of depressive and manic symptoms calls for less biased and more objective markers. By using electronic devices, fine-grained data on complex psychopathological aspects of bipolar disorder can be evaluated unobtrusively over the long term. Moreover, electronic data could possibly represent candidate markers of diagnosis and illness activity in bipolar disorder and allow for early and individualized intervention for prodromal symptoms outside clinical settings. 
The present dissertation concerns the use of electronic monitoring as a marker and treatment intervention in bipolar disorder and investigated the scientific literature and body of evidence within the area, which includes ten original study reports and two systematic reviews, one of which included a meta-analysis, conducted by the author of the dissertation. 
Taken together, the literature presented in this dissertation illustrates that 1) smartphone-based electronic self-monitoring of mood seems to reflect clinically assessed depressive and manic symptoms and enables the long-term characterization of mood

instability in bipolar disorder; 2) preliminary results suggest that smartphone-based automatically generated data (e.g. the number of text messages sent/day; the number of incoming and outgoing calls/day; the number of changes in cell tower IDs/day; and voice features) seem to reflect clinically assessed depressive and manic symptoms in bipolar disorder; 3) smartphone-based electronic self-monitoring had no effects on the severity of depressive and manic symptoms in bipolar disorder, according to a randomized controlled trial; and 4) electronic monitoring of psychomotor

  11. Bipolar soft connected, bipolar soft disconnected and bipolar soft compact spaces

    Directory of Open Access Journals (Sweden)

    Muhammad Shabir

    2017-06-01

    Full Text Available Bipolar soft topological spaces are mathematical expressions to estimate interpretation of data frameworks. Bipolar soft theory considers the core features of data granules. Bipolarity is important to distinguish between positive information which is guaranteed to be possible and negative information which is forbidden or surely false. Connectedness and compactness are the most important fundamental topological properties. These properties highlight the main features of topological spaces and distinguish one topology from another. Taking this into account, we explore the bipolar soft connectedness, bipolar soft disconnectedness and bipolar soft compactness properties for bipolar soft topological spaces. Moreover, we introduce the notion of bipolar soft disjoint sets, bipolar soft separation, and bipolar soft hereditary property and study on bipolar soft connected and disconnected spaces. By giving the detailed picture of bipolar soft connected and disconnected spaces we investigate bipolar soft compact spaces and derive some results related to this concept.

  12. Novel approach to epicardial pacemaker implantation in patients with limited venous access.

    Science.gov (United States)

    Costa, Roberto; Scanavacca, Mauricio; da Silva, Kátia Regina; Martinelli Filho, Martino; Carrillo, Roger

    2013-11-01

    Limited venous access in certain patients increases the procedural risk and complexity of conventional transvenous pacemaker implantation. The purpose of this study was to determine a minimally invasive epicardial approach using pericardial reflections for dual-chamber pacemaker implantation in patients with limited venous access. Between June 2006 and November 2011, 15 patients underwent epicardial pacemaker implantation. Procedures were performed through a minimally invasive subxiphoid approach and pericardial window with subsequent fluoroscopy-assisted lead placement. Mean patient age was 46.4 ± 15.3 years (9 male [(60.0%], 6 female [40.0%]). The new surgical approach was used in patients determined to have limited venous access due to multiple abandoned leads in 5 (33.3%), venous occlusion in 3 (20.0%), intravascular retention of lead fragments from prior extraction in 3 (20.0%), tricuspid valve vegetation currently under treatment in 2 (13.3%), and unrepaired intracardiac defects in 2 (13.3%). All procedures were successful with no perioperative complications or early deaths. Mean operating time for isolated pacemaker implantation was 231.7 ± 33.5 minutes. Lead placement on the superior aspect of right atrium, through the transverse sinus, was possible in 12 patients. In the remaining 3 patients, the atrial lead was implanted on the left atrium through the oblique sinus, the postcaval recess, or the left pulmonary vein recess. None of the patients displayed pacing or sensing dysfunction, and all parameters remained stable throughout the follow-up period of 36.8 ± 25.1 months. Epicardial pacemaker implantation through pericardial reflections is an effective alternative therapy for those patients requiring physiologic pacing in whom venous access is limited. © 2013 Heart Rhythm Society. All rights reserved.

  13. Genetics Home Reference: bipolar disorder

    Science.gov (United States)

    ... Email Facebook Twitter Home Health Conditions Bipolar disorder Bipolar disorder Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Bipolar disorder is a mental health condition that causes extreme ...

  14. BIPOLAR DISORDER: A REVIEW

    OpenAIRE

    Pathan Dilnawaz N; Ziyaurrahaman A.R; Bhise K.S.

    2010-01-01

    Bipolar disorder (BD) is a severe psychiatric disorder that results in poor global functioning, reduced quality of life and high relapse rates. Research finds that many adults with bipolar disorder identify the onset of symptoms in childhood and adolescence, indicating the importance of early accurate diagnosis and treatment. Accurate diagnosis of mood disorders is critical for treatment to be effective. Distinguishing between major depression and bipolar disorders, especially the depressed p...

  15. A pacemaker powered by an implantable biofuel cell operating under conditions mimicking the human blood circulatory system--battery not included.

    Science.gov (United States)

    Southcott, Mark; MacVittie, Kevin; Halámek, Jan; Halámková, Lenka; Jemison, William D; Lobel, Robert; Katz, Evgeny

    2013-05-07

    Biocatalytic electrodes made of buckypaper were modified with PQQ-dependent glucose dehydrogenase on the anode and with laccase on the cathode and were assembled in a flow biofuel cell filled with serum solution mimicking the human blood circulatory system. The biofuel cell generated an open circuitry voltage, Voc, of ca. 470 mV and a short circuitry current, Isc, of ca. 5 mA (a current density of 0.83 mA cm(-2)). The power generated by the implantable biofuel cell was used to activate a pacemaker connected to the cell via a charge pump and a DC-DC converter interface circuit to adjust the voltage produced by the biofuel cell to the value required by the pacemaker. The voltage-current dependencies were analyzed for the biofuel cell connected to an Ohmic load and to the electronic loads composed of the interface circuit, or the power converter, and the pacemaker to study their operation. The correct pacemaker operation was confirmed using a medical device - an implantable loop recorder. Sustainable operation of the pacemaker was achieved with the system closely mimicking human physiological conditions using a single biofuel cell. This first demonstration of the pacemaker activated by the physiologically produced electrical energy shows promise for future electronic implantable medical devices powered by electricity harvested from the human body.

  16. Assessing and addressing cognitive impairment in bipolar disorder

    DEFF Research Database (Denmark)

    Miskowiak, K W; Burdick, K E; Martinez-Aran, A

    2018-01-01

    OBJECTIVES: Cognition is a new treatment target to aid functional recovery and enhance quality of life for patients with bipolar disorder. The International Society for Bipolar Disorders (ISBD) Targeting Cognition Task Force aimed to develop consensus-based clinical recommendations on whether, when...... in Bipolar Disorder Rating Assessment, and (III) evaluate the impact of medication and comorbidity, refer patients for comprehensive neuropsychological evaluation when clinically indicated, and encourage patients to build cognitive reserve. Regarding question (IV), there is limited evidence for current...

  17. High rate lithium-thionyl chloride bipolar battery development

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.G.; Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1994-12-31

    The lithium/thionyl chloride system is capable of providing both high power and high energy density when cells containing thin components are arranged in a bipolar configuration. Electrode current densities in excess of 300mA/cm{sup 2} are achieved during pulse discharge. The present work is concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells.

  18. Bipolar Disorder in Women

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2013-06-01

    Full Text Available The research on gender's role in bipolar disorders has drawn significant interest recently. The presentation and course of bipolar disorder differs between women and men. Women experience depressive episodes, dysphoric mood, mixed states, rapid cycling and seasonal patterns more often than men. Comorbidity, particularly thyroid disease, migraine, obesity, and anxiety disorders laso occur more frequently in women than men. On the other hand men with bipolar disorder are also more likely than women to have problems with drug or alcohol abuse. The pregnancy and postpartum period is a time of high risk for onset and recurrence of bipolar disorder in women.

  19. A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. IV. Entrainment : Pacemaker as Clock

    NARCIS (Netherlands)

    Pittendrigh, Colin S.; Daan, Serge

    1976-01-01

    1. In the first part of the paper, the model of non-parametric entrainment of circadian pacemakers is tested for the case of nocturnal rodents. The model makes use of the available data on freerunning period (τ) in constant darkness and on phase response curves (PRC) for short light pulses. It is

  20. Treatment of vasovagal syncope: pacemaker or crossing legs?

    NARCIS (Netherlands)

    van Dijk, N.; Harms, M. P.; Linzer, M.; Wieling, W.

    2000-01-01

    A 50-year-old male patient continued to experience syncope after implantation of a pacemaker. During cardiovascular examination, the patient showed a typical vasovagal response, with normal pacemaker function. Leg crossing, which prohibits the pooling of blood in the legs and abdomen, at the onset

  1. State of the art of cardiac pacemaker technology

    International Nuclear Information System (INIS)

    Lambeck, R.

    1978-01-01

    The development of cardiac pacemakers from fixed-frequency to demand pacemakers is reviewed. The latter is described in more detail with regard to its energy sources and its design. The use of radioactive energy sources is illustrated by the example of 238 Pu and 147 promethium and a comparison of the two radiation sources. (AJ) 891 AJ [de

  2. Case of pacemaker pocket infection caused by Finegoldia magna.

    Science.gov (United States)

    Hosseini Dehkordi, Seyed Hamed; Osorio, Georgina

    2017-10-01

    Finegoldia magna (formerly called Peptostreptococcus magnus) is a Gram-positive anaerobic coccus which is increasingly recognized as an opportunistic pathogen. We present a case of F. magna associated non-valvular cardiovascular device-related infection in an 83 year-old male who received a permanent pacemaker for sick sinus syndrome seven weeks prior to his presentation. Five weeks after the implantation, the pacemaker and leads were explanted because of clinical evidence of pacemaker pocket infection. He was initially treated with sulfamethoxazole-trimethoprim based on the Gram stain results from the removed pacemaker. However, two weeks later, he was readmitted with sepsis and was successfully treated with ampicillin-sulbactam. Culture results from the pacemaker and pocket as well as blood cultures grew F. magna. Clinicians should be aware of the possibility of F. magna infection when initial gram stain results show "gram positive cocci". Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Radiation therapy in patients with electric cardiac pacemakers

    International Nuclear Information System (INIS)

    Bisping, H.J.; Stockberg, H.; Meyer, J.; Frik, W.; Technische Hochschule Aachen

    1977-01-01

    In the course of radiation therapy and connected diagnostic measures ionizing radiation and other sources of disturbance may interfere with the function of permanent pacemakers. The conditions of such hazards are investigated in theory and practice making allowance for the different susceptibility to trouble of various models of permanent pacemakers. It appears that no extension of long-term follow-up of the cardiac pacemaker's function is needed with regard to possible late effects of ionizing radiation, but that the follow-up of pacemaker-patients during their first period of treatment should not be neglected, since other sources of electronic interference may be present. Routine checks at radiotherapy installations should also include possible sources of disturbance to electronic pacemakers. (orig.) [de

  4. The cardiac pacemaker patient. Might the pacer be directly irradiated?

    International Nuclear Information System (INIS)

    Tsekos, A.; Momm, F.; Brunner, M.; Guttenberger, R.

    2000-01-01

    According to recommendations listed in a recent review, pacemakers generally should not be irradiated directly. They should be shielded from ionizing radiation or their position changed. Direct irradiation can cause pacemaker failure. There are no clinical signals to indicate a near failure. When controlling pacemaker function, there is often a change in the magnetic frequency before malfunction occurs. If a malfunction results in a partial heart failure only, there would be enough time to implant another pacemaker. As can be seen from a case described here, a policy of 'wait and see' may be adopted even if there are changes in the magnetic frequency. if there is any danger to the patient's life, the feasibility of using an external pacemaker system may be explored, especially in cases where there is a strong need for radiotherapy (severe pain, infiltration of plexus). Risks and benefits should be carefully weighed and discussed with the patient

  5. Pacemaker syndrome with sub-acute left ventricular systolic dysfunction in a patient with a dual-chamber pacemaker: consequence of lead switch at the header.

    Science.gov (United States)

    Khurwolah, Mohammad Reeaze; Vezi, Brian Zwelethini

    In the daily practice of pacemaker insertion, the occurrence of atrial and ventricular lead switch at the pacemaker box header is a rare and unintentional phenomenon, with less than five cases reported in the literature. The lead switch may have dire consequences, depending on the indication for the pacemaker. One of these consequences is pacemaker syndrome, in which the normal sequence of atrial and ventricular activation is impaired, leading to sub-optimal ventricular filling and cardiac output. It is important for the attending physician to recognise any worsening of symptoms in a patient who has recently had a permanent pacemaker inserted. In the case of a dual-chamber pacemaker, switching of the atrial and ventricular leads at the pacemaker box header should be strongly suspected. We present an unusual case of pacemaker syndrome and right ventricular-only pacinginduced left ventricular systolic dysfunction in a patient with a dual-chamber pacemaker.

  6. Thwarted interpersonal needs and suicide ideation: Comparing psychiatric inpatients with bipolar and non-bipolar mood disorders.

    Science.gov (United States)

    Taylor, Nathanael J; Mitchell, Sean M; Roush, Jared F; Brown, Sarah L; Jahn, Danielle R; Cukrowicz, Kelly C

    2016-12-30

    Psychiatric inpatients are at heightened risk for suicide, and evidence suggests that psychiatric inpatients with bipolar mood disorders may be at greater risk for suicide ideation compared to those with non-bipolar mood disorders. There is a paucity of research directly comparing risk factors for suicide ideation in bipolar versus non-bipolar mood disorders in an inpatient sample. The current study sought to clarify the association between two constructs from the interpersonal theory of suicide (i.e., perceived burdensomeness and thwarted belongingness) in leading to suicide ideation among psychiatric inpatients with bipolar and non-bipolar mood disorders. Participants were (N=90) psychiatric inpatients with a bipolar (n = 20) or non-bipolar mood disorder (n=70; per their medical charts). Perceived burdensomeness, but not thwarted belongingness, was significantly associated with suicide ideation after adjusting for other covariates. This suggests perceived burdensomeness may play a key role in suicide ideation among psychiatric inpatients with any mood disorder and highlights the importance of assessment and intervention of perceived burdensomeness in this population. Contrary to our hypothesis, mood disorder group (i.e., bipolar versus non-bipolar) did not moderate the relations between perceived burdensomeness/thwarted belongingness and suicide ideation. Published by Elsevier Ireland Ltd.

  7. Patients with atrial fibrillation and permanent pacemaker

    DEFF Research Database (Denmark)

    Dalgaard, Frederik; Ruwald, Martin H; Lindhardt, Tommi Bo

    2018-01-01

    BACKGROUND: The management of patients with non-valvular atrial fibrillation (NVAF) with rate-lowering or anti-arrhythmic drugs has markedly changed over the last decade, but it is unknown how these changes have affected patients with NVAF with a permanent pacemaker (PPM). METHODS: Through Danish......,261. Thus, the proportional amount of NVAF patients with a PPM decreased from 1.3% to 1.1% (p = 0.015). Overall 45.9% had atrial fibrillation (AF) duration less than one year and the proportion declined from 55.5% to 42.4% (p

  8. Clear cell hidradenocarcinoma developing in pacemaker pocket.

    Science.gov (United States)

    Reyes, Cesar V

    2008-11-01

    An octagenerian woman developed clear cell hidradenocarcinoma, a rare neoplasm of eccrine sweat gland origin, 4 years following pacemaker implantation in her right lateral chest. The tumor immunohistochemically mimicked a metastatic lobular breast carcinoma, for example, strongly positive estrogen, weakly positive progesterone, and weakly reactive mammoglobin. A complete surgical excision of the tumor was complemented with ipsilateral dissection of involved adjacent axillary lymph nodes. Recommended irradiation was refused by the patient. Retrospective 3-year mammogram review, 2-year postsurgery follow-up, and complete postmortem evaluation failed to prove a primary breast malignancy or other metastatic lesion elsewhere.

  9. The thermodynamics of bipolarity: a bifurcation model of bipolar illness and bipolar character and its psychotherapeutic applications.

    Science.gov (United States)

    Sabelli, H C; Carlson-Sabelli, L; Javaid, J I

    1990-11-01

    Two models dominate current formulations of bipolar illness: the homeostatic model implicit in Freud's psychodynamics and most neuroamine deficit/excess theories; and the oscillatory model of exaggerated biological rhythms. The homeostatic model is based on the closed systems approach of classic thermodynamics, while the oscillatory model requires the open systems approach of modern thermodynamics. Here we present a thermodynamic model of bipolarity that includes both homeostatic and oscillatory features and adds the most important feature of open systems thermodynamics: the creation of novel structures in bifurcation processes. According to the proposed model, bipolarity is the result of exaggerated biological energy that augments homeostatic, oscillatory and creative psychological processes. Only low-energy closed systems tend to rest ("point attractor") and entropic disorder. Open processes containing and exchanging energy fluctuate between opposite states ("periodic attractors"); they are characteristic of most physiological rhythms and are exaggerated in bipolar subjects. At higher energies, their strong fluctuations destroy pre-existing patterns and structures, produce turbulence ("chaotic attractors"), which sudden switches between opposite states, and create new and more complex structures. Likewise, high-energy bipolars develop high spontaneity, great fluctuations between opposite moods, internal and interpersonal chaos, and enhanced creativity (personal, artistic, professional) as well as psychopathology (personality deviations, psychotic delusions). Offered here is a theoretical explanation of the dual--creative and destructive--nature of bipolarity in terms of the new enantiodromic concept of entropy generalized by process theory. Clinically, this article offers an integrative model of bipolarity that accounts for many clinical features and contributes to a definition of the bipolar personality.

  10. Pacemaker implantation complication rates in elderly and young patients

    Directory of Open Access Journals (Sweden)

    Özcan KS

    2013-08-01

    Full Text Available Kazim Serhan Özcan, Damirbek Osmonov, Servet Altay, Cevdet Dönmez, Ersin Yildirim, Ceyhan Türkkan, Baris Güngör, Ahmet Ekmekçi, Ahmet Taha Alper, Kadir Gürkan, İzzet ErdinlerDepartment of Cardiology, Siyami Ersek Cardiovascular and Thoracic Surgery Center, Istanbul, TurkeyAims: To evaluate the complication rate differences between elderly and younger patients who receive a permanent pacemaker implantation.Methods: We reviewed all cases admitted to our institution between January 2008 and June 2009 with symptomatic bradyarrhythmia for whom a permanent pacemaker was implanted. Beginning in June 2009, we prospectively collected data from all patients with the same diagnosis and procedure. The frequency of complications due to the pacemaker implantation procedure was evaluated and compared between young (<70 years old and elderly (≥70 years old patients.Results: Among 574 patients with a permanent pacemaker, 259 patients (45.1% were below and 315 patients (54.9% were above or at 70 years of age. There were 240 (92.7% and 19 (7.3% dual-chamber pacemaker (DDD and single-chamber pacemaker (VVI implanted patients in the younger group, and 291 (76.8% and 73 (23.2% DDD and VVI pacemaker implanted patients in the elderly group, respectively. The complication rate was 39 (15.1% out of 259 young patients and 24 (7.6% out of 315 elderly patients. Postprocedural complications were statistically lower in the elderly patients than in younger patients (P = 0.005.Conclusion: A pacemaker implantation performed by an experienced operator is a safe procedure for patients of advanced age. The patients who are above 70 years old may have less complication rates than the younger patients.Keywords: complications of pacemaker implantation, elderly patients, permanent pacemaker

  11. From Pacemaker to Wearable: Techniques for ECG Detection Systems.

    Science.gov (United States)

    Kumar, Ashish; Komaragiri, Rama; Kumar, Manjeet

    2018-01-11

    With the alarming rise in the deaths due to cardiovascular diseases (CVD), present medical research scenario places notable importance on techniques and methods to detect CVDs. As adduced by world health organization, technological proceeds in the field of cardiac function assessment have become the nucleus and heart of all leading research studies in CVDs in which electrocardiogram (ECG) analysis is the most functional and convenient tool used to test the range of heart-related irregularities. Most of the approaches present in the literature of ECG signal analysis consider noise removal, rhythm-based analysis, and heartbeat detection to improve the performance of a cardiac pacemaker. Advancements achieved in the field of ECG segments detection and beat classification have a limited evaluation and still require clinical approvals. In this paper, approaches on techniques to implement on-chip ECG detector for a cardiac pacemaker system are discussed. Moreover, different challenges regarding the ECG signal morphology analysis deriving from medical literature is extensively reviewed. It is found that robustness to noise, wavelet parameter choice, numerical efficiency, and detection performance are essential performance indicators required by a state-of-the-art ECG detector. Furthermore, many algorithms described in the existing literature are not verified using ECG data from the standard databases. Some ECG detection algorithms show very high detection performance with the total number of detected QRS complexes. However, the high detection performance of the algorithm is verified using only a few datasets. Finally, gaps in current advancements and testing are identified, and the primary challenge remains to be implementing bullseye test for morphology analysis evaluation.

  12. 21 CFR 870.3680 - Cardiovascular permanent or temporary pacemaker electrode.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiovascular permanent or temporary pacemaker... § 870.3680 Cardiovascular permanent or temporary pacemaker electrode. (a) Temporary pacemaker electrode—(1) Identification. A temporary pacemaker electrode is a device consisting of flexible insulated...

  13. Testing of Common Electromagnetic Environments for Risk of Interference with Cardiac Pacemaker Function

    Directory of Open Access Journals (Sweden)

    Maria Tiikkaja

    2013-09-01

    Conclusions: Modern pacemakers are well shielded against external EMFs, and workers with a pacemaker can most often return to their previous work after having a pacemaker implanted. However, an appropriate risk assessment is still necessary after the implantation of a pacemaker, a change of its generator, or major modification of its programming settings.

  14. Suicide in bipolar disorder: a review.

    Science.gov (United States)

    Latalova, Klara; Kamaradova, Dana; Prasko, Jan

    2014-06-01

    Suicide is a leading cause of death in patients with bipolar disorder. Risk factors and prevention of suicide in this illness are the focus of considerable current research. MEDLINE data base was searched for the key words "bipolar disorder" with "suicide", "lithium" with "suicide", "anticonvulsants" with "bipolar disorder", and "anticonvulsants" with "bipolar disorder" and with "suicide". No language or time constraints were applied. The lists of references were searched manually to find additional articles. It is estimated that 25% to 50% of patients with bipolar disorder will attempt suicide at least once over their lifetime, and that 8% to 19% will complete suicide. Mortality rates from cardiovascular diseases are elevated in bipolar disorder. Risk factors for suicide include younger age of onset of the illness, history of past suicidal behavior, family history of suicide acts, comorbid borderline personality disorder and substance use disorders, and hopelessness. The warning signs calling for immediate action include the patients threatening to harm themselves, or looking for ways to kill themselves (seeking access to pills or weapons), or the patient talking or writing about death. Robust evidence supports the effects of lithium treatment in reducing suicidal attempts and completions in bipolar disorder. The evidence for antisuicidal effects of anticonvulsants is weaker. Nevertheless, valproate and other anticonvulsants are frequently prescribed as mood stabilizers. There have been controversial suggestions that this treatment may elevate the risk of suicide, but the data supporting this are not convincing. Psychoeducation can reduce the number of suicide attempts and completions. Suicide in bipolar disorder is a major public health problem. Recent research has expanded our knowledge of risk factors and warning signs. Nevertheless, it appears that the introduction of lithium treatment in the 1970s was the most recent important breakthrough in the prevention

  15. Comparative familial aggregation of bipolar disorder in patients with bipolar I and bipolar II disorders.

    Science.gov (United States)

    Parker, Gordon B; Romano, Mia; Graham, Rebecca K; Ricciardi, Tahlia

    2018-05-01

    We sought to quantify the prevalence and differential prevalence of a bipolar disorder among family members of patients with a bipolar I or II disorder. The sample comprised 1165 bipolar and 1041 unipolar patients, with the former then sub-typed as having either a bipolar I or II condition. Family history data was obtained via an online self-report tool. Prevalence of a family member having a bipolar disorder (of either sub-type) was distinctive (36.8%). Patients with a bipolar I disorder reported a slightly higher family history (41.2%) compared to patients with a bipolar II disorder (36.3%), and with both significantly higher than the rate of bipolar disorder in family members of unipolar depressed patients (18.5%). Findings support the view that bipolar disorder is heritable. The comparable rates in the two bipolar sub-types support the positioning of bipolar II disorder as a valid condition with strong genetic underpinnings.

  16. Evaluating the pacemaker effect with the pump parameter of gated blood-pool imaging

    International Nuclear Information System (INIS)

    Cheng Muhua

    1995-01-01

    13 normal controls and 27 patients with ventricular pacemaker had undergone planar gated blood-pool imaging in different conditions. Result shows: (1) Pump parameters can successfully reflect therapeutic effect of pacemaker among them EMP is the most valuable parameter for evaluating the cardiac pumping effect. (2) After implantation of the ventricular pacemaker, the LVEF did not increase, but the CO and EMP was significantly increased. (3) Compared with right ventricular demand pacemaker, the rate-responsive ventricular pacemaker give better hemodynamic benefit at exercise condition. (4) Through restrained cardiac pacemaker the functional change was analyzed on or off pace, and monitoring the cardiac function itself after the pacemaker was implanted

  17. Risk factors for suicide among children and youths with bipolar spectrum and early bipolar disorder.

    Science.gov (United States)

    Rajewska-Rager, Aleksandra; Sibilski, Piotr; Lepczyńska, Natalia

    2015-01-01

    In recent years much attention has been given to determine risk factors for suicide among adults with bipolar disorder. Such studies concerning children and youths, which would also take into account the specificity of the developmental age, are still too few. The ability to identify risk factors for children and youths with mood disorders, as well as the possibility to monitor them, is an essential element in preventing suicidal behaviours. Previous studies have clearly indicated that in the group of patients with an early onset of the bipolar disorder the occurrence of suicidal thoughts and intentions were significantly increased. Identifying the risk of suicide is hindered further by the complexity of the phenomenon, which is a compound interaction of various factors: biological, environmental, sociological, psychological and clinical. This is especially true with young adults suffering from mental illness and presenting a number of other psychopathological symptoms. The following paper introduces and reviews the results of current studies, which analysed the risk factors for suicide among children and youths with bipolar spectrum or already diagnosed with bipolar disorder. For this purpose we conducted the overview of recent years literature available in PubMed/MEDLINE database, including the following search criteria: early onset bipolar disorder, bipolar disorder in children and young people, the spectrum of bipolar disorder, and suicidal ideation, suicidal intent, suicide.

  18. Properties of Bipolar Fuzzy Hypergraphs

    OpenAIRE

    Akram, M.; Dudek, W. A.; Sarwar, S.

    2013-01-01

    In this article, we apply the concept of bipolar fuzzy sets to hypergraphs and investigate some properties of bipolar fuzzy hypergraphs. We introduce the notion of $A-$ tempered bipolar fuzzy hypergraphs and present some of their properties. We also present application examples of bipolar fuzzy hypergraphs.

  19. SU-E-T-802: Verification of Implanted Cardiac Pacemaker Doses in Intensity-Modulated Radiation Therapy: Dose Prediction Accuracy and Reduction Effect of a Lead Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J [Dept. of Radiation Oncology, Konkuk University Medical Center, Seoul (Korea, Republic of); Chung, J [Dept. of Radiation Oncology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2015-06-15

    Purpose: To verify delivered doses on the implanted cardiac pacemaker, predicted doses with and without dose reduction method were verified using the MOSFET detectors in terms of beam delivery and dose calculation techniques in intensity-modulated radiation therapy (IMRT). Methods: The pacemaker doses for a patient with a tongue cancer were predicted according to the beam delivery methods [step-and-shoot (SS) and sliding window (SW)], intensity levels for dose optimization, and dose calculation algorithms. Dosimetric effects on the pacemaker were calculated three dose engines: pencil-beam convolution (PBC), analytical anisotropic algorithm (AAA), and Acuros-XB. A lead shield of 2 mm thickness was designed for minimizing irradiated doses to the pacemaker. Dose variations affected by the heterogeneous material properties of the pacemaker and effectiveness of the lead shield were predicted by the Acuros-XB. Dose prediction accuracy and the feasibility of the dose reduction strategy were verified based on the measured skin doses right above the pacemaker using mosfet detectors during the radiation treatment. Results: The Acuros-XB showed underestimated skin doses and overestimated doses by the lead-shield effect, even though the lower dose disagreement was observed. It led to improved dose prediction with higher intensity level of dose optimization in IMRT. The dedicated tertiary lead sheet effectively achieved reduction of pacemaker dose up to 60%. Conclusion: The current SS technique could deliver lower scattered doses than recommendation criteria, however, use of the lead sheet contributed to reduce scattered doses.Thin lead plate can be a useful tertiary shielder and it could not acuse malfunction or electrical damage of the implanted pacemaker in IMRT. It is required to estimate more accurate scattered doses of the patient with medical device to design proper dose reduction strategy.

  20. SU-E-T-802: Verification of Implanted Cardiac Pacemaker Doses in Intensity-Modulated Radiation Therapy: Dose Prediction Accuracy and Reduction Effect of a Lead Sheet

    International Nuclear Information System (INIS)

    Lee, J; Chung, J

    2015-01-01

    Purpose: To verify delivered doses on the implanted cardiac pacemaker, predicted doses with and without dose reduction method were verified using the MOSFET detectors in terms of beam delivery and dose calculation techniques in intensity-modulated radiation therapy (IMRT). Methods: The pacemaker doses for a patient with a tongue cancer were predicted according to the beam delivery methods [step-and-shoot (SS) and sliding window (SW)], intensity levels for dose optimization, and dose calculation algorithms. Dosimetric effects on the pacemaker were calculated three dose engines: pencil-beam convolution (PBC), analytical anisotropic algorithm (AAA), and Acuros-XB. A lead shield of 2 mm thickness was designed for minimizing irradiated doses to the pacemaker. Dose variations affected by the heterogeneous material properties of the pacemaker and effectiveness of the lead shield were predicted by the Acuros-XB. Dose prediction accuracy and the feasibility of the dose reduction strategy were verified based on the measured skin doses right above the pacemaker using mosfet detectors during the radiation treatment. Results: The Acuros-XB showed underestimated skin doses and overestimated doses by the lead-shield effect, even though the lower dose disagreement was observed. It led to improved dose prediction with higher intensity level of dose optimization in IMRT. The dedicated tertiary lead sheet effectively achieved reduction of pacemaker dose up to 60%. Conclusion: The current SS technique could deliver lower scattered doses than recommendation criteria, however, use of the lead sheet contributed to reduce scattered doses.Thin lead plate can be a useful tertiary shielder and it could not acuse malfunction or electrical damage of the implanted pacemaker in IMRT. It is required to estimate more accurate scattered doses of the patient with medical device to design proper dose reduction strategy

  1. Influence of digital and analogue cellular telephones on implanted pacemakers.

    Science.gov (United States)

    Altamura, G; Toscano, S; Gentilucci, G; Ammirati, F; Castro, A; Pandozi, C; Santini, M

    1997-10-01

    The aim of this study was to find out whether digital and analogue cellular 'phones affect patients with pacemakers. The study comprised continuous ECG monitoring of 200 pacemaker patients. During the monitoring certain conditions caused by interference created by the telephone were looked for: temporary or prolonged pacemaker inhibition; a shift to asynchronous mode caused by electromagnetic interference; an increase in ventricular pacing in dual chamber pacemakers, up to the programmed upper rate. The Global System for Mobile Communications system interfered with pacing 97 times in 43 patients (21.5%). During tests on Total Access of Communication System telephones, there were 60 cases of pacing interference in 35 patients (17.5%). There were 131 interference episodes during ringing vs 26 during the on/off phase; (P 4 s) was seen at the pacemaker 'base' sensing value in six patients using the Global system but in only one patient using Total Access. Cellular 'phones may be dangerous for pacemaker patients. However, they can be used safely if patients do not carry the 'phone close to the pacemaker, which is the only place where high risk interference has been observed.

  2. Neck Pain One Week after Pacemaker Generator Replacement.

    Science.gov (United States)

    Graham, Ross F; Wightman, John M

    2015-07-01

    The incidence of cardiac pacemaker implantation has risen markedly in the past three decades, making awareness of possible postprocedural complications critical to the emergency physician. This case is the first documented instance of internal jugular (IJ) deep vein thrombosis (DVT) from an uncomplicated pacemaker generator replacement. A patient presented to an Emergency Department with a 2-day history of mild left temporal headache migrating to his left neck. The patient did not volunteer this information, but review of systems revealed a temporary transvenous pacemaker inserted through the right IJ vein 1 week previously during a routine exchange of a left-sided cardiac pacemaker generator. Manipulation of the existing pacemaker wires entering the left subclavian vein was minimal. Computed tomographic angiography of the neck demonstrated near-complete thrombotic occlusion of the entire length of his left IJ vein. This required hospital admission for observation and treatment with anticoagulation. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: DVT, with thrombotic extension into adjacent vessels anywhere along the course of pacemaker wires, should be considered by the emergency provider in the evaluation of head, neck, or upper extremity symptoms after recent or remote implantation or manipulation of a transvenous cardiac pacemaker, including generator replacement. Failure to identify and treat appropriately could result in significant morbidity and mortality from airway edema, septic thrombophlebitis, superior vena cava syndrome, superior sagittal sinus thrombosis, or pulmonary embolism. Published by Elsevier Inc.

  3. Conduction disturbances after TAVR: Electrophysiological studies and pacemaker dependency.

    Science.gov (United States)

    Makki, Nader; Dollery, Jenn; Jones, Danielle; Crestanello, Juan; Lilly, Scott

    Permanent pacemaker (PPM) placement occurs in 5-20% of patients after transcatheter aortic valve replacement (TAVR). Although predictors of pacemaker implantation have been established, features that predispose patients to pacemaker utilization on follow up have not been widely reported. We performed a retrospective review of patients undergoing commercial TAVR between 2011 and 2016. We collated patients that underwent in-hospital PPM implantation and had a follow up of at least 3months. Data abstraction was performed for electrophysiological studies (EPS), pacemaker indication, timing, and device interrogation for pacemaker dependency on follow up. A total of 24 patients received in-hospital PPM post-TAVR (14% of total cohort), and mean follow up was 22months. Indications for PPM included resting complete heart block (CHB; 15/24, 63%), left bundle branch block and abnormal electrophysiological study (EPS; 7/24, 29%), alternating bundle branch block (1/24, 4%) and tachy-brady syndrome (1/24, 4%). Pacemaker dependency (underlying ventricular asystole, complete heart block, or >50% pacing) occurred in 8/24 patients (33%) during follow-up, 7 of whom had resting CHB, and one with CHB invoked during EPS. Pacemaker dependency after TAVR is common among those that exhibited CHB, but not among those with a prolonged HV delay during EPS. Although preliminary, these observations are relevant to management of rhythm disturbances after TAVR, and may inform the practice of EPS-based PPM implantation. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Modern Perspectives on Numerical Modeling of Cardiac Pacemaker Cell

    Science.gov (United States)

    Maltsev, Victor A.; Yaniv, Yael; Maltsev, Anna V.; Stern, Michael D.; Lakatta, Edward G.

    2015-01-01

    Cardiac pacemaking is a complex phenomenon that is still not completely understood. Together with experimental studies, numerical modeling has been traditionally used to acquire mechanistic insights in this research area. This review summarizes the present state of numerical modeling of the cardiac pacemaker, including approaches to resolve present paradoxes and controversies. Specifically we discuss the requirement for realistic modeling to consider symmetrical importance of both intracellular and cell membrane processes (within a recent “coupled-clock” theory). Promising future developments of the complex pacemaker system models include the introduction of local calcium control, mitochondria function, and biochemical regulation of protein phosphorylation and cAMP production. Modern numerical and theoretical methods such as multi-parameter sensitivity analyses within extended populations of models and bifurcation analyses are also important for the definition of the most realistic parameters that describe a robust, yet simultaneously flexible operation of the coupled-clock pacemaker cell system. The systems approach to exploring cardiac pacemaker function will guide development of new therapies, such as biological pacemakers for treating insufficient cardiac pacemaker function that becomes especially prevalent with advancing age. PMID:24748434

  5. Proton Beam Therapy Interference With Implanted Cardiac Pacemakers

    International Nuclear Information System (INIS)

    Oshiro, Yoshiko; Sugahara, Shinji; Noma, Mio; Sato, Masato; Sakakibara, Yuzuru; Sakae, Takeji; Hayashi, Yasutaka; Nakayama, Hidetsugu; Tsuboi, Koji; Fukumitsu, Nobuyoshi; Kanemoto, Ayae; Hashimoto, Takayuki; Tokuuye, Koichi

    2008-01-01

    Purpose: To investigate the effect of proton beam therapy (PBT) on implanted cardiac pacemaker function. Methods and Materials: After a phantom study confirmed the safety of PBT in patients with cardiac pacemakers, we treated 8 patients with implanted pacemakers using PBT to a total tumor dose of 33-77 gray equivalents (GyE) in dose fractions of 2.2-6.6 GyE. The combined total number of PBT sessions was 127. Although all pulse generators remained outside the treatment field, 4 patients had pacing leads in the radiation field. All patients were monitored by means of electrocardiogram during treatment, and pacemakers were routinely examined before and after PBT. Results: The phantom study showed no effect of neutron scatter on pacemaker generators. In the study, changes in heart rate occurred three times (2.4%) in 2 patients. However, these patients remained completely asymptomatic throughout the PBT course. Conclusions: PBT can result in pacemaker malfunctions that manifest as changes in pulse rate and pulse patterns. Therefore, patients with cardiac pacemakers should be monitored by means of electrocardiogram during PBT

  6. Effect of telecobalt irradiation on the function of implantable pacemaker

    International Nuclear Information System (INIS)

    Toyoda, Michiaki

    1986-01-01

    In patients implanted with a pacemaker, radiotherapy may be chosen as the treatment when malignant tumor is complicated. Therefore, on the assumption that the pacemaker apparatus is exposed to X-ray, 21 lithium cells used for CMOS or TTL circuit were collected before expiration date and irradiated with 60 Co. The pacemaker used were 10 apparatuses of unprogrammed model VVI, 9 apparatuses of programmed model VVI and 2 apparatuses programmed model DVI. Irradiation was done up to 1,000 rads in dividing doses or at 1,000 rads as a single dose. Observations were made for effects on intervals, amplitude and wave shape of stimula to pacemaker, power, sensitivity, refractory phase, and program functions. In conclusion, it was found that pacemaker is sure to be affected considerably for various functions, although no functional arrest occurs, under irradiation up to 1,000 rads of 60 Co in dividing dose. When irradiation at 1,000 rads was given as a single dose, dysfunctions of pacemaker developed in some cases indicating that direct irradiation at high doses is contraindicated for pacemakers using much of LSI-CMOS. (author)

  7. A devices' game of thrones: cardiac resynchronization therapy vs. pacemaker.

    Science.gov (United States)

    Moura-Ferreira, Sara; Gonçalves, Helena; Oliveira, Marco; Primo, João; Fonseca, Paulo; Ribeiro, José; Santos, Elisabeth; Pelicano, Nuno; Martins, Dinis; Gama, Vasco

    2017-12-01

    Oversensing can interfere with biventricular pacing. Cardiac Resynchronization Therapy (CRT) output inhibition due to automatic brady mode change from a sensing to a pacing mode of a previously implanted pacemaker as it reached battery capacity depleted indicator has not been previously published in the medical literature. We report the first case of CRT output inhibition in a pacemaker dependent patient due to electrical stimuli from a previously right-sided implanted pacemaker, after unaware reversion of OVO mode (O = no chambers paced; V = ventricular sensing; O = no response to sensing) to backup VVI (V = ventricular pacing; V = ventricular sensing; I = inhibitory response to sensing) when it reached the elective replacement interval. This paper emphasizes the importance of knowing the distinct pacemaker brady mode behaviours after battery capacity depleted indicator has been reached, according to the pacemakers' manufacturer, including the possibility of automatic brady mode change from sensing to pacing mode. It also highlights the potential for severe bradycardia or asystole of this automatic brady mode change from a previously implanted pacemaker in pacemaker dependent patients submitted to CRT upgrade. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  8. Cardiovascular patients’ experiences of living with pacemaker: Qualitative study

    Directory of Open Access Journals (Sweden)

    Morteza Ghojazadeh

    2015-09-01

    Full Text Available BACKGROUND: A pacemaker implantation is considered major life event for cardiovascular patients, so they will probably have very interesting experiences of living with this device. The aim of this study was to explore the experiences of cardiovascular patients living with the pacemaker. METHODS: In this qualitative study, 27 patients were chosen through purposive sampling to achieve data saturation, and their experiences were examined using semi-structured interviews. The patients’ statements were recorded with their consent and analyzed using content analysis method. RESULTS: Participants’ experiences included three main themes: “Problems and limitations,” “feeling and dealing with pacemaker”, and “sources of comfort” and 10 sub-themes including: physical problems, financial problems, social problems, the first encounter, the feeling of living with the pacemaker, how to cope with pacemaker, satisfaction with pacemaker, good family support, hospital and hospital staff performance, and role of religious beliefs. CONCLUSION: Planning to solve social problems, identifying and changing feelings of patients using pacemakers, reinforcing the resources of comfort especially family support seem to be necessary steps for improving quality of life and impact of using pacemaker

  9. Hemodynamic instability after pulmonary veins isolation in a patient with dual chamber pacemaker

    Science.gov (United States)

    Kiuchi, Márcio Galindo; Lobato, Guilherme Miglioli; Chen, Shaojie

    2017-01-01

    Abstract Introduction: The standard treatment of sinus node dysfunction (SND) is the pacemaker implantation, and the ideal methodology for the management of atrial fibrillation (AF) is rhythm control, but this is sometimes very hard to accomplish. For such actions, complete isolation of all pulmonary veins (PVI) is currently widely accepted as the best endpoint. Case Presentation: In this case, we report a female patient, 81 years old, with controlled hypertension, without coronary artery disease, bearer of bilateral knee replacement, and dual chamber pacemaker implanted 1.5 years ago owing to sinus node disease, presenting the following symptoms: presyncope episodes associated with sustained irregular palpitation tachycardia. The evaluation of the pacemaker-recorded episodes of atrial fibrillation, the echocardiogram-presented normal systolic function and measurements, as well as the resting myocardial scintigraphy and with drug use did not demonstrate ischemia and/or fibrosis. The patient was in use of valsartan 320 mg daily, amlodipine 10 mg daily, sotalol hydrochloride 120 mg 2 times daily, and dabigatran 110 mg 2 times daily. At the end of the PVI, the patient presented hemodynamic instability, with a decrease in heart rate to 30 bpm and invasive arterial blood pressure to 60/30 mmHg. The pericardial puncture was quickly carried out with the possibility of cardiac tamponade as the first hypothesis, but no pericardial effusion was found. Next, we detected acute capture loss from the ventricular pacemaker lead, unvarying with high voltage and pulse width, even with stable impedance, sense and keeping the same position visualized by fluoroscopy. And there was soon afterwards induction of sustained ventricular tachycardia degenerating to spontaneous ventricular fibrillation. Electrical cardioversion-defibrillation was performed with 200J, and the sinus rhythm was reestablished, but there was a dead short, and the pacemaker generator was burned and

  10. Electrical resistivity change in Al:ZnO thin films dynamically deposited by bipolar pulsed direct-current sputtering and a remote plasma source

    International Nuclear Information System (INIS)

    Yang, Wonkyun; Joo, Junghoon

    2010-01-01

    The Al-doped ZnO (AZO) thin films for a transparent conducting oxide in solar cell devices were deposited by bipolar pulsed dc magnetron sputtering. This work was performed in an in-line type system and investigated AZO films in a static deposition mode and dynamic one, which is more important in the practical fields. Because of this dynamic deposition process, the zigzagged columnar structure was observed. This resulted in the decreasing electrical property, optical properties, and surface roughness. As a deposition in the dynamic mode, the resistivity increased from 1.64x10 -3 to 2.50x10 -3 Ω cm, as compared to that in the static mode, and the transmittance also decreased from 83.9% to 78.3%. To recover the disadvantage, a remote plasma source (RPS) was supported between the substrate and target for reducing zigzagged formation during the deposition. The deposition rate decreased by using RPS, but the electrical and optical properties of films got better than only dynamic mode. The resistivity and transmittance in the dynamic mode using RPS were 2.1x10 -3 Ω cm and 85.5%, respectively. In this study, the authors found the possibility to advance the electrical and optical properties of AZO thin films in the industry mode.

  11. Acute pericarditis with cardiac tamponade induced by pacemaker implantation.

    Science.gov (United States)

    Shingaki, Masami; Kobayashi, Yutaka; Suzuki, Haruo

    2015-11-01

    An 87-year-old woman was diagnosed with third-degree atrioventricular block and underwent pacemaker implantation. On postoperative day 12, she experienced cardiac tamponade that was suspected on computed tomography to be caused by lead perforation; therefore, we performed open-heart surgery. However, we could not identify a perforation site on the heart, and drained a 400-mL exudative pericardial effusion. Subsequently, we diagnosed the pericardial effusion as due to pericarditis induced by pacemaker implantation. It is sometimes difficult to distinguish pericarditis from pacemaker lead perforation, so both should be included in the differential diagnosis. © The Author(s) 2014.

  12. Endocardial Pacemaker Implantation in Neonates and Infants

    Directory of Open Access Journals (Sweden)

    Canan Ayabakan

    2006-04-01

    Full Text Available Transvenous pacemaker lead implantation is the preferred method of pacing in adult patients. Lead performance and longevity are superior and the implantation approach can be performed under local anaesthetic with a very low morbidity. In children, and especially in neonates and infants, the epicardial route was traditionally chosen until the advent of smaller generators and lead implantation techniques that allowed growth of the child without lead displacement. Endocardial implantation is not universally accepted, however, as there is an incidence of venous occlusion of the smaller veins of neonates and infants with concerns for loss of venous access in the future. Growing experience with lower profile leads, however, reveals that endocardial pacing too can be performed with low morbidity and good long-term results in neonates and infants.

  13. Cardiac pacemaker. [electric-battery powered

    Energy Technology Data Exchange (ETDEWEB)

    Kolenik, S A

    1976-01-02

    The construction of a cardiac pacemaker is described which is characterized by particularly small dimensions, small weight and long life duration. The weight is under 100g, the specific weight under 1.7. Mass inertia forces which occur through acceleration and retardation processes, thus remain below the threshold values, above which one would have to reckon with considerable damaging of the surrounding body tissue. The maintaining of small size and slight weight is achieved by using an oscillator on COSMOS basis, where by considerably lower energy consumption, among others the lifetimes of the batteries used - a lithium anode with thionyl chloride electrolyte - is extended to over 5 years. The reliability can be increased by the use of 2 or more batteries. The designed dimension are 20x60x60 mm/sup 3/.

  14. What is Bipolar Disorder?

    Science.gov (United States)

    ... down” Have trouble sleeping Think about death or suicide Can someone have bipolar disorder along with other problems? Yes. Sometimes people having very strong mood episodes may have psychotic symptoms. Psychosis affects thoughts ...

  15. Neutron absorbed dose in a pacemaker CMOS

    Energy Technology Data Exchange (ETDEWEB)

    Borja H, C. G.; Guzman G, K. A.; Valero L, C. Y.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Paredes G, L., E-mail: candy_borja@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The absorbed dose due to neutrons by a Complementary Metal Oxide Semiconductor (CMOS) has been estimated using Monte Carlo methods. Eventually a person with a pacemaker becomes a patient that must be treated by radiotherapy with a linear accelerator; the pacemaker has integrated circuits as CMOS that are sensitive to intense and pulsed radiation fields. When the Linac is working in Bremsstrahlung mode an undesirable neutron field is produced due to photoneutron reactions; these neutrons could damage the CMOS putting the patient at risk during the radiotherapy treatment. In order to estimate the neutron dose in the CMOS a Monte Carlo calculation was carried out where a full radiotherapy vault room was modeled with a W-made spherical shell in whose center was located the source term of photoneutrons produced by a Linac head operating in Bremsstrahlung mode at 18 MV. In the calculations a phantom made of tissue equivalent was modeled while a beam of photoneutrons was applied on the phantom prostatic region using a field of 10 x 10 cm{sup 2}. During simulation neutrons were isotropically transported from the Linac head to the phantom chest, here a 1 {theta} x 1 cm{sup 2} cylinder made of polystyrene was modeled as the CMOS, where the neutron spectrum and the absorbed dose were estimated. Main damages to CMOS are by protons produced during neutron collisions protective cover made of H-rich materials, here the neutron spectrum that reach the CMOS was calculated showing a small peak around 0.1 MeV and a larger peak in the thermal region, both connected through epithermal neutrons. (Author)

  16. Intra-cardiac pacemaker infection: Surgical management and outcome

    Directory of Open Access Journals (Sweden)

    Sameh Elameen

    2016-05-01

    Conclusion: Explantation of the complete pacemaker system has proved a reliable method to eradicate infection. Complications were rare, except in patients who present lately in a critically ill condition and septic shock.

  17. From two competing oscillators to one coupled-clock pacemaker cell system

    Science.gov (United States)

    Yaniv, Yael; Lakatta, Edward G.; Maltsev, Victor A.

    2015-01-01

    At the beginning of this century, debates regarding “what are the main control mechanisms that ignite the action potential (AP) in heart pacemaker cells” dominated the electrophysiology field. The original theory which prevailed for over 50 years had advocated that the ensemble of surface membrane ion channels (i.e., “M-clock”) is sufficient to ignite rhythmic APs. However, more recent experimental evidence in a variety of mammals has shown that the sarcoplasmic reticulum (SR) acts as a “Ca2+-clock” rhythmically discharges diastolic local Ca2+ releases (LCRs) beneath the cell surface membrane. LCRs activate an inward current (likely that of the Na+/Ca2+ exchanger) that prompts the surface membrane “M-clock” to ignite an AP. Theoretical and experimental evidence has mounted to indicate that this clock “crosstalk” operates on a beat-to-beat basis and determines both the AP firing rate and rhythm. Our review is focused on the evolution of experimental definition and numerical modeling of the coupled-clock concept, on how mechanisms intrinsic to pacemaker cell determine both the heart rate and rhythm, and on future directions to develop further the coupled-clock pacemaker cell concept. PMID:25741284

  18. Pacemaker lead fracture without an increase in lead impedance caused by cardiac fibroma

    Directory of Open Access Journals (Sweden)

    Daisuke Sato

    2013-12-01

    Full Text Available We report the case of a 64-year-old man who had a permanent pacemaker with a unipolar silicone electrode positioned in the right ventricle in 1989 for sinus node dysfunction. On a routine checkup in June 2011, a 28-mm-diameter mass was discovered, which appeared to adhere to the tricuspid valve and the ventricular lead. The size of the mass did not change for the next 6 months, and the lead impedance was maintained at around 500–600 Ω. Because pacing failure was observed in January 2012, he underwent an urgent pacemaker check; however, the lead impedance was found not to have increased greatly (689 Ω. Nevertheless, the pacemaker lead was noted to be fractured at the tricuspid level. His echocardiogram showed new severe tricuspid regurgitation and a floating mass around the lead. We extracted the fractured lead, enucleated the tumor, replaced the tricuspid valve, and placed an epicardial lead. Macroscopic examination revealed that the tumor surrounded the fractured lead and covered the stump. Pathological examination revealed that the tumor was composed of fibrous connective tissue. We presumed that electric current continued to flow through the stump of the fractured unipolar lead to the generator, and this might have caused the limited increase in lead impedance.

  19. Anxiety, stress and perfectionism in bipolar disorder.

    Science.gov (United States)

    Corry, Justine; Green, Melissa; Roberts, Gloria; Frankland, Andrew; Wright, Adam; Lau, Phoebe; Loo, Colleen; Breakspear, Michael; Mitchell, Philip B

    2013-12-01

    Previous reports have highlighted perfectionism and related cognitive styles as a psychological risk factor for stress and anxiety symptoms as well as for the development of bipolar disorder symptoms. The anxiety disorders are highly comorbid with bipolar disorder but the mechanisms that underpin this comorbidity are yet to be determined. Measures of depressive, (hypo)manic, anxiety and stress symptoms and perfectionistic cognitive style were completed by a sample of 142 patients with bipolar disorder. Mediation models were used to explore the hypotheses that anxiety and stress symptoms would mediate relationships between perfectionistic cognitive styles, and bipolar disorder symptoms. Stress and anxiety both significantly mediated the relationship between both self-critical perfectionism and goal attainment values and bipolar depressive symptoms. Goal attainment values were not significantly related to hypomanic symptoms. Stress and anxiety symptoms did not significantly mediate the relationship between self-critical perfectionism and (hypo)manic symptoms. 1. These data are cross-sectional; hence the causality implied in the mediation models can only be inferred. 2. The clinic patients were less likely to present with (hypo)manic symptoms and therefore the reduced variability in the data may have contributed to the null findings for the mediation models with (hypo) manic symptoms. 3. Those patients who were experiencing current (hypo)manic symptoms may have answered the cognitive styles questionnaires differently than when euthymic. These findings highlight a plausible mechanism to understand the relationship between bipolar disorder and the anxiety disorders. Targeting self-critical perfectionism in the psychological treatment of bipolar disorder when there is anxiety comorbidity may result in more parsimonious treatments. © 2013 Published by Elsevier B.V.

  20. Elektrokirurgi hos patienter med pacemaker og implanterbar kardioverter-defibrillator

    DEFF Research Database (Denmark)

    Lønnberg, Ann Sophie Claire; Philberts, Berit Thornvig; Bonde, Christian

    2017-01-01

    Electrosurgery is a very useful tool and one of the most commonly used techniques. However, the technique can interfere with pacemakers and implantable cardioverter defibrillators. This article provides practical recommendations for the use of electrosurgery in these patients.......Electrosurgery is a very useful tool and one of the most commonly used techniques. However, the technique can interfere with pacemakers and implantable cardioverter defibrillators. This article provides practical recommendations for the use of electrosurgery in these patients....

  1. Successful pacing using a batteryless sunlight-powered pacemaker.

    Science.gov (United States)

    Haeberlin, Andreas; Zurbuchen, Adrian; Schaerer, Jakob; Wagner, Joerg; Walpen, Sébastien; Huber, Christoph; Haeberlin, Heinrich; Fuhrer, Juerg; Vogel, Rolf

    2014-10-01

    Today's cardiac pacemakers are powered by batteries with limited energy capacity. As the battery's lifetime ends, the pacemaker needs to be replaced. This surgical re-intervention is costly and bears the risk of complications. Thus, a pacemaker without primary batteries is desirable. The goal of this study was to test whether transcutaneous solar light could power a pacemaker. We used a three-step approach to investigate the feasibility of sunlight-powered cardiac pacing. First, the harvestable power was estimated. Theoretically, a subcutaneously implanted 1 cm(2) solar module may harvest ∼2500 µW from sunlight (3 mm implantation depth). Secondly, ex vivo measurements were performed with solar cells placed under pig skin flaps exposed to a solar simulator and real sunlight. Ex vivo measurements under real sunlight resulted in a median output power of 4941 µW/cm(2) [interquartile range (IQR) 3767-5598 µW/cm(2), median skin flap thickness 3.0 mm (IQR 2.7-3.3 mm)]. The output power strongly depended on implantation depth (ρSpearman = -0.86, P pacemaker powered by a 3.24 cm(2) solar module was implanted in vivo in a pig to measure output power and to pace. In vivo measurements showed a median output power of >3500 µW/cm(2) (skin flap thickness 2.8-3.84 mm). Successful batteryless VVI pacing using a subcutaneously implanted solar module was performed. Based on our results, we estimate that a few minutes of direct sunlight (irradiating an implanted solar module) allow powering a pacemaker for 24 h using a suitable energy storage. Thus, powering a pacemaker by sunlight is feasible and may be an alternative energy supply for tomorrow's pacemakers. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  2. ARTERIAL HYPERTENSION AND MEDICAL SUPPORT OF PATIENTS WITH PERMANENT PACEMAKERS

    Directory of Open Access Journals (Sweden)

    T. A. Derienko

    2016-06-01

    Full Text Available The review is devoted to clinical problems of arterial hypertension (AH in patients with implanted pacemakers (EKS and cardiac resynchronization therapy (CRT. Indications for pacemaker implantation and CRT are considered, especially the purpose and effectiveness of angiotensin-converting enzyme (ACE inhibitors, angiotensin II receptor antagonists (ARA, sartans, beta-blockers (BAB, diuretics, calcium channel blockers. We prove that the CRT and cardiac pacing and do not cancel, bur modify drug therapy of AH.

  3. Pacemaker implantation after catheter ablation for atrial fibrillation.

    Science.gov (United States)

    Deshmukh, Abhishek J; Yao, Xiaoxi; Schilz, Stephanie; Van Houten, Holly; Sangaralingham, Lindsey R; Asirvatham, Samuel J; Friedman, Paul A; Packer, Douglas L; Noseworthy, Peter A

    2016-01-01

    Sinus node dysfunction requiring pacemaker implantation is commonly associated with atrial fibrillation (AF), but may not be clinically apparent until restoration of sinus rhythm with ablation or cardioversion. We sought to determine frequency, time course, and predictors for pacemaker implantation after catheter ablation, and to compare the overall rates to a matched cardioversion cohort. We conducted a retrospective analysis using a large US commercial insurance database and identified 12,158 AF patients who underwent catheter ablation between January 1, 2005 and December 31, 2012. Over an average of 2.4 years of follow-up, 5.6 % of the patients underwent pacemaker implantation. Using the Cox proportional hazards models, we found that risk of risks of pacemaker implantation was associated with older age (50-64 and ≥65 versus pacemaker implantation between ablation patients and propensity score (PS)-matched cardioversion groups (3.5 versus. 4.1 % at 1 year and 8.8 versus 8.3 % at 5 years). Overall, pacemaker implantation occurs in about 1/28 patients within 1 year of catheter ablation. The overall implantation rate decreased between 2005 and 2012. Furthermore, the risk after ablation is similar to cardioversion, suggesting that patients require pacing due to a common underlying electrophysiologic substrate, rather than the ablation itself.

  4. Nickel hydrogen bipolar battery electrode design

    Science.gov (United States)

    Puglisi, V. J.; Russell, P.; Verrier, D.; Hall, A.

    1985-01-01

    The preferred approach of the NASA development effort in nickel hydrogen battery design utilizes a bipolar plate stacking arrangement to obtain the required voltage-capacity configuration. In a bipolar stack, component designs must take into account not only the typical design considerations such as voltage, capacity and gas management, but also conductivity to the bipolar (i.e., intercell) plate. The nickel and hydrogen electrode development specifically relevant to bipolar cell operation is discussed. Nickel oxide electrodes, having variable type grids and in thicknesses up to .085 inch are being fabricated and characterized to provide a data base. A selection will be made based upon a system level tradeoff. Negative (hydrpogen) electrodes are being screened to select a high performance electrode which can function as a bipolar electrode. Present nickel hydrogen negative electrodes are not capable of conducting current through their cross-section. An electrode was tested which exhibits low charge and discharge polarization voltages and at the same time is conductive. Test data is presented.

  5. Bipolar magnetic semiconductor in silicene nanoribbons

    International Nuclear Information System (INIS)

    Farghadan, Rouhollah

    2017-01-01

    Highlights: • A new electronic phase for silicene nanoribbon in the presence of electric and magnetic fields. • Bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps in silicene. • Robust bipolar magnetic semiconductor features in a rough silicene. • Perfect and reversible spin polarization in silicene nanoribbon junctions. - Abstract: A theoretical study was presented on generation of spin polarization in silicene nanoribbons using the single-band tight-binding approximation and the non-equilibrium Green’s function formalism. We focused on the effect of electric and exchange magnetic fields on the spin-filter capabilities of zigzag-edge silicene nanoribbons in the presence of the intrinsic spin-orbit interaction. The results show that a robust bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps can be obtained when exchange magnetic and electric field strengths are both larger than the intrinsic spin-orbit interaction. Therefore, zigzag silicene nanoribbons could act as bipolar and perfect spin filter devices with a large spin-polarized current and a reversible spin polarization in the vicinity of the Fermi energy. We also investigated the effect of edge roughness and found that the bipolar magnetic semiconductor features are robust against edge disorder in silicene nanoribbon junctions. These results may be useful in multifunctional spin devices based on silicene nanoribbons.

  6. Bipolar magnetic semiconductor in silicene nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Farghadan, Rouhollah, E-mail: rfarghadan@kashanu.ac.ir

    2017-08-01

    Highlights: • A new electronic phase for silicene nanoribbon in the presence of electric and magnetic fields. • Bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps in silicene. • Robust bipolar magnetic semiconductor features in a rough silicene. • Perfect and reversible spin polarization in silicene nanoribbon junctions. - Abstract: A theoretical study was presented on generation of spin polarization in silicene nanoribbons using the single-band tight-binding approximation and the non-equilibrium Green’s function formalism. We focused on the effect of electric and exchange magnetic fields on the spin-filter capabilities of zigzag-edge silicene nanoribbons in the presence of the intrinsic spin-orbit interaction. The results show that a robust bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps can be obtained when exchange magnetic and electric field strengths are both larger than the intrinsic spin-orbit interaction. Therefore, zigzag silicene nanoribbons could act as bipolar and perfect spin filter devices with a large spin-polarized current and a reversible spin polarization in the vicinity of the Fermi energy. We also investigated the effect of edge roughness and found that the bipolar magnetic semiconductor features are robust against edge disorder in silicene nanoribbon junctions. These results may be useful in multifunctional spin devices based on silicene nanoribbons.

  7. Are working memory deficits in bipolar disorder markers for psychosis?

    Science.gov (United States)

    Allen, Daniel N; Randall, Carol; Bello, Danielle; Armstrong, Christina; Frantom, Linda; Cross, Chad; Kinney, Jefferson

    2010-03-01

    Working memory deficits have been identified in bipolar disorder, but there is evidence suggesting that these deficits may be markers for psychosis rather than affective disorder. The current study examined this issue by comparing two groups of individuals with bipolar disorder, one with psychotic features and one without psychotic features, with a group of normal controls. Working memory was conceptualized as a multicomponent system that includes auditory and visuospatial short-term stores, executive control processes, and an episodic buffer that allows for communication between short- and long-term memory stores (Baddeley & Logie, 1999). Results indicated that only executive control processes significantly differentiated the psychotic and nonpsychotic bipolar groups, although visuospatial working memory differentiated both bipolar groups from controls. The results support the idea that some aspects of working memory performance are markers for psychosis, while others may be more general markers for bipolar disorders. Copyright 2010 APA, all rights reserved

  8. Impact of Pacemaker Lead Characteristics on Pacemaker Related Infection and Heart Perforation: A Nationwide Population-Based Cohort Study.

    Science.gov (United States)

    Lin, Yu-Sheng; Chen, Tien-Hsing; Hung, Sheng-Ping; Chen, Dong Yi; Mao, Chun-Tai; Tsai, Ming-Lung; Chang, Shih-Tai; Wang, Chun-Chieh; Wen, Ming-Shien; Chen, Mien-Cheng

    2015-01-01

    Several risk factors for pacemaker (PM) related complications have been reported. However, no study has investigated the impact of lead characteristics on pacemaker-related complications. Patients who received a new pacemaker implant from January 1997 to December 2011 were selected from the Taiwan National Health Insurance Database. This population was grouped according to the pacemaker lead characteristics in terms of fixation and insulation. The impact of the characteristics of leads on early heart perforation was analyzed by multivariable logistic regression analysis, while the impact of the lead characteristics on early and late infection and late heart perforation over a three-year period were analyzed using Cox regression. This study included 36,104 patients with a mean age of 73.4±12.5 years. In terms of both early and late heart perforations, there were no significant differences between groups across the different types of fixation and insulations. In the multivariable Cox regression analysis, the pacemaker-related infection rate was significantly lower in the active fixation only group compared to either the both fixation (OR, 0.23; 95% CI, 0.07-0.80; P = 0.020) or the passive fixation group (OR, 0.26; 95% CI, 0.08-0.83; P = 0.023). There was no difference in heart perforation between active and passive fixation leads. Active fixation leads were associated with reduced risk of pacemaker-related infection.

  9. Impact of Pacemaker Lead Characteristics on Pacemaker Related Infection and Heart Perforation: A Nationwide Population-Based Cohort Study.

    Directory of Open Access Journals (Sweden)

    Yu-Sheng Lin

    Full Text Available Several risk factors for pacemaker (PM related complications have been reported. However, no study has investigated the impact of lead characteristics on pacemaker-related complications.Patients who received a new pacemaker implant from January 1997 to December 2011 were selected from the Taiwan National Health Insurance Database. This population was grouped according to the pacemaker lead characteristics in terms of fixation and insulation. The impact of the characteristics of leads on early heart perforation was analyzed by multivariable logistic regression analysis, while the impact of the lead characteristics on early and late infection and late heart perforation over a three-year period were analyzed using Cox regression. This study included 36,104 patients with a mean age of 73.4±12.5 years. In terms of both early and late heart perforations, there were no significant differences between groups across the different types of fixation and insulations. In the multivariable Cox regression analysis, the pacemaker-related infection rate was significantly lower in the active fixation only group compared to either the both fixation (OR, 0.23; 95% CI, 0.07-0.80; P = 0.020 or the passive fixation group (OR, 0.26; 95% CI, 0.08-0.83; P = 0.023.There was no difference in heart perforation between active and passive fixation leads. Active fixation leads were associated with reduced risk of pacemaker-related infection.

  10. Family environment patterns in families with bipolar children.

    Science.gov (United States)

    Belardinelli, Cecilia; Hatch, John P; Olvera, Rene L; Fonseca, Manoela; Caetano, Sheila C; Nicoletti, Mark; Pliszka, Steven; Soares, Jair C

    2008-04-01

    We studied the characteristics of family functioning in bipolar children and healthy comparison children. We hypothesized that the family environment of bipolar children would show greater levels of dysfunction as measured by the Family Environment Scale (FES). We compared the family functioning of 36 families that included a child with DSM-IV bipolar disorder versus 29 comparison families that included only healthy children. All subjects and their parents were assessed with the K-SADS-PL interview. The parents completed the FES to assess their current family functioning. Multivariate analysis of variance was used to compare the family environment of families with and without offspring with bipolar disorder. Parents of bipolar children reported lower levels of family cohesion (pfamilies where a parent had a history of mood disorders compared to families where parents had no history of mood disorders. Length of illness in the affected child was inversely associated with family cohesion (r=-0.47, p=0.004). Due to the case-control design of the study, we cannot comment on the development of these family problems or attribute their cause specifically to child bipolar disorder. Families with bipolar children show dysfunctional patterns related to interpersonal interactions and personal growth. A distressed family environment should be addressed when treating children with bipolar disorder.

  11. Spanish Pacemaker Registry. Thirteenth Official Report of the Spanish Society of Cardiology Working Group on Cardiac Pacing (2015).

    Science.gov (United States)

    Pombo Jiménez, Marta; Cano Pérez, Óscar; Fidalgo Andrés, María Luisa; Lorente Carreño, Diego; Coma Samartín, Raúl

    2016-12-01

    We describe the results of the analysis of the devices implanted and conveyed to the Spanish Pacemaker Registry in 2015. The report is based on the processing of information provided by the European Pacemaker Patient Identification Card. We received information from 111 hospitals, with a total of 12 555 cards, representing 32.1% of all the estimated activity. The use of conventional generators and resynchronization devices was 820 and 73 units per million population, respectively. The mean age of the patients receiving an implantation was 77.7 years, and more than 50% of the devices were implanted in patients over 80 years of age. Overall, 58.6% of the implants and 58.8% of the replacements were performed in men. All of the endocardial leads employed were bipolar, 81.5% had an active fixation system, and 16.5% were compatible with magnetic resonance. Although dual chamber sequential pacing continues to be more widespread, pacing with VVI/R mode is used because up to 23.8% of the patients with sinus node disease are in sinus rhythm, as are 24.1% of those with atrioventricular block. The total use of pacemaker generators in Spain has increased by about 5% with respect to 2014. The majority of the leads implanted are of active fixation, and less than 20% are protected from magnetic resonance. The factors directly related to the selection of pacing mode are age and sex. In around 20% of patients, the choice of the pacing mode could be improved. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  12. Bipolar Affective Disorder and Migraine

    Directory of Open Access Journals (Sweden)

    Birk Engmann

    2012-01-01

    Full Text Available This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and bipolar disorder, including both genetic and neuropathological approaches, is broadly discussed. Moreover, bipolar disorder and migraine are often combined with a variety of other affective disorders, and, furthermore, behavioural factors also play a role in the origin and course of the diseases. Approach to treatment options is also difficult. Several papers point out possible remedies, for example, valproate, topiramate, which acts on both diseases, but no first-choice treatments have been agreed upon yet.

  13. Depression and Bipolar Support Alliance

    Science.gov (United States)

    Depression and Bipolar Support Alliance Crisis Hotline Information Coping with a Crisis Suicide Prevention Information Psychiatric Hospitalization ... sign-up Education info, training, events Mood Disorders Depression Bipolar Disorder Anxiety Screening Center Co-occurring Illnesses/ ...

  14. Bipolar Disorder and Cancer

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2012-06-01

    Full Text Available Prevalence studies and studies on causation relations have shown that the relation between psychiatric disorders and chronic physical diseases is neglected. For heterogeneous diseases an increasing number of susceptibility variants are being defined. Alzheimer disease, bipolar disorder, breast and prostate cancer, coronary artery disease, Chron's disease, systemic lupus eritematosus, type 1 and type 2 diabetes mellitus are mentioned together with epigenetic concept. In acrocentric zone of chromosome 13, breast cancer, retinoblastoma, chronic Iymphocytic leukemia genes with B cells, dopamin loci of bipolar disorder are found together. Among bipolar and healthy individuals, an increase risk of breast cancer in female cases has been resported. On the other hand, psychosocial factors that affect stress and response to stress itself may be important variables in prognosis and progression of different cancer types. During the course of many cancer types –especially brain tumors- and during treatment of chemotherapeutic agents, bipolar symptomatology may appear. In this article, it is reviewed with relevant literature that whether an etiological relation between bipolar disorder and cancer exist and how both diseases affect each other's course and treatment.

  15. [Right heart failure after pacemaker implantation].

    Science.gov (United States)

    Gallego Galiana, Juan; López Castellanos, Genoveva; Gioia, Francesca; Ruiz Ortega, Raúl Antonio; Cobo Reinoso, Maria Eugenia; Manzano Espinosa, Luis

    2015-06-22

    Severe tricuspid regurgitation (TR) secondary to interference pacemaker (PM) cable is a rare cause of progressive right heart failure (HF), which can worsen patient outcomes. We present 3 clinical cases of right HF secondary to TR after PM implantation. In these patients the clinic is right HF, which can appear early, as in our second patient, or after years of implementation of the PM, as in the first and third patients. The diagnosis is confirmed by echocardiography, the most accurate 3D, followed by transesophageal. The 2D transthoracic can not detect it, because it has low sensitivity for TR associated with PM. Medical treatment is always the first choice, since any other procedure carries significant morbidity and mortality. Probably this is a condition that we will diagnose with increasing frequency, because there are more and more patients with devices and, at the same time, the diagnostic tools are improving. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  16. Radioisotope thermoelectric generators for implanted pacemakers

    Energy Technology Data Exchange (ETDEWEB)

    Pustovalov, A.A.; Bovin, A.V.; Fedorets, V.I.; Shapovalov, V.P.

    1986-08-01

    This paper discusses the development and application of long-life lithium batteries and the problems associated with miniature radioisotope thermoelectric generators (RITEG) with service lives of 10 years or longer. On eof the main problems encountered when devising a radioisotope heat source (RHS) for an RITEG is to obtain biomedical /sup 238/PuO/sub 2/ with a specific neutron yield of 3.10/sup 3/-4.10/sup 3/ (g /SUP ./ sec)/sup -1/, equivalent to metallic Pu 238, and with a content of gamma impurities sufficient to ensure a permissible exposure a permissible exposure does rate (EDR) of a mixture of neutron and gamma radiation. After carrying out the isotope exchange and purifying the initial sample of its gamma impurity elements, the authors obtain biomedical Pu 238 satisfying the indicated requirements king suitable for use in the power packs of medical devices. Taking the indicated specifications into account, the Ritm-1o and gamma radioisotope heat sources were designed, built, tested in models and under natural conditions, and then into production as radioisotope thermoelectric generators designed to power the electronic circuits of implanted pacemakers. The Ritm-MT and Gemma radioisotope thermoelectric generators described are basic units, which can be used as self-contained power supplies for electronic equipment with power requirements in the micromilliwatt range.

  17. Incidence of ventricular tachyarrhythmias during permanent pacemaker therapy in low-risk patients results from the German multicentre EVENTS study.

    Science.gov (United States)

    Faber, Thomas S; Gradinger, Robert; Treusch, Sven; Morkel, Carsten; Brachmann, Johannes; Bode, Christoph; Zehender, Manfred

    2007-09-01

    Current studies found an incidence of 12-31% ventricular tachyarrhythmias and sudden cardiac death during cardiac pacing months or even years after pacemaker insertion. MADIT(12) and MUSTT(13) demonstrated that patients with poor LV function after Myocardial infarction (MI) showing non-sustained ventricular tachycardia (nsVT) and inducibility during electrophysiologic testing benefit from an ICD. The present study was dedicated to assess the global incidence of non-sustained ventricular arrhythmias in a general population of pacemaker patients. Special regard was on patients with a potential ICD indication, e.g. those matching the MADIT/MUSTT criteria. Two hundred and thirty-one patients (72 +/- 11 years; 134 men) with an indication for dual chamber pacing entered the study. In all patients pacemaker systems capable of automatic storing of intracardiac electrocardiograms were implanted (Pulsar, Discovery, Guidant). Follow-up time was 15 months after inclusion. In 54 (25.7%) of 210 patients with at least one follow-up, episodes of nsVT were documented by stored electrocardiograms (up to >30 beats, >200 b.p.m.). Multiple-up to nine-episodes of ventricular tachycardia were retrieved in 31 of these patients. Three out of 14 patients with an LVEF <40% after MI presented nsVT during the follow-up. One of these patients received an ICD. A significant number of pacemaker patients present with ventricular tachycardia. Intracardiac electrocardiograms and alert functions from pacemakers may enhance physicians' awareness of the patient's intrinsic arrhythmic profile and help uncover underlying mechanisms of arrhythmias by storing the initiation of the arrhythmia.

  18. Spiral–pacemaker interactions in a mathematical model of excitable medium

    International Nuclear Information System (INIS)

    Shajahan, T K; Borek, Bartłomiej; Shrier, Alvin; Glass, Leon

    2013-01-01

    Interactions of a spiral wave with a pacemaker is studied in a mathematical model of two dimensional excitable medium. Faster pacemakers emitting target waves can abolish spirals by driving them to the border of the medium. Our study shows that a slower pacemaker can modify spiral wave behavior by changing the motion of the spiral core. We analyze the dynamics of the spiral wave near the spiral core and away from the core as a function of size and period of the pacemaker. The pacemaker can cause the spiral wave to drift towards it, and either speed up or slow down the reentrant activity. Furthermore, the drift induced by the pacemaker can result in irregular or quasiperiodic dynamics even at sites away from the pacemaker. These results highlight the influence of pacemakers on complex spiral wave dynamics. (paper)

  19. Modulation of brain response to emotional conflict as a function of current mood in bipolar disorder: preliminary findings from a follow-up state-based fMRI study.

    Science.gov (United States)

    Rey, Gwladys; Desseilles, Martin; Favre, Sophie; Dayer, Alexandre; Piguet, Camille; Aubry, Jean-Michel; Vuilleumier, Patrik

    2014-08-30

    We used functional magnetic resonance imaging (fMRI) to examine affective control longitudinally in a group of patients with bipolar disorder (BD). Participants comprised 12 BD patients who underwent repeated fMRI scans in euthymic (n=11), depressed (n=9), or hypomanic (n=9) states, and were compared with 12 age-matched healthy controls. During fMRI, participants performed an emotional face-word interference task with either low or high attentional demands. Relative to healthy controls, patients showed decreased activation of the cognitive control network normally associated with conflict processing, more severely during hypomania than during depression, but regardless of level of task demand in both cases. During euthymia, a decreased response to conflict was observed only during the high load condition. Additionally, unlike healthy participants, patients exhibited deactivation in several key areas in response to emotion-conflict trials - including the rostral anterior cingulate cortex during euthymia, the hippocampus during depression, and the posterior cingulate cortex during hypomania. Our results indicate that the ability of BD patients to recruit control networks when processing affective conflict, and the abnormal suppression of activity in distinct components of the default mode network, may depend on their current clinical state and attentional demand. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Nanosecond bipolar pulse generators for bioelectrics.

    Science.gov (United States)

    Xiao, Shu; Zhou, Chunrong; Yang, Enbo; Rajulapati, Sambasiva R

    2018-04-26

    Biological effects caused by a nanosecond pulse, such as cell membrane permeabilization, peripheral nerve excitation and cell blebbing, can be reduced or cancelled by applying another pulse of reversed polarity. Depending on the degree of cancellation, the pulse interval of these two pulses can be as long as dozens of microseconds. The cancellation effect diminishes as the pulse duration increases. To study the cancellation effect and potentially utilize it in electrotherapy, nanosecond bipolar pulse generators must be made available. An overview of the generators is given in this paper. A pulse forming line (PFL) that is matched at one end and shorted at the other end allows a bipolar pulse to be produced, but no delay can be inserted between the phases. Another generator employs a combination of a resistor, an inductor and a capacitor to form an RLC resonant circuit so that a bipolar pulse with a decaying magnitude can be generated. A third generator is a converter, which converts an existing unipolar pulse to a bipolar pulse. This is done by inserting an inductor in a transmission line. The first phase of the bipolar pulse is provided by the unipolar pulse's rising phase. The second phase is formed during the fall time of the unipolar pulse, when the inductor, which was previously charged during the flat part of the unipolar pulse, discharges its current to the load. The fourth type of generator uses multiple MOSFET switches stacked to turn on a pre-charged, bipolar RC network. This approach is the most flexible in that it can generate multiphasic pulses that have different amplitudes, delays, and durations. However, it may not be suitable for producing short nanosecond pulses (<100 ns), whereas the PFL approach and the RLC approach with gas switches are used for this range. Thus, each generator has its own advantages and applicable range. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Patients exposure from fluoroscopic guided pacemaker implantation procedures

    Energy Technology Data Exchange (ETDEWEB)

    Alkhorayef, M.; Babikir, E. [King Saud University, College of Applied Sciences, Radiological Sciences Department, P. O. Box 10219, Riyadh 11433 (Saudi Arabia); Sulieman, A. [Prince Sattam bin Abdulaziz University, College of Applied Medical Sciences, Radiology and Medical Imaging Department, P. O. Box 422, Alkharj 11942 (Saudi Arabia); Daar, E. [University of Jordan, Faculty of Science, Department of Physics, Amman 11942 (Jordan); Alnaaimi, M.; Alduaij, M. [Kuwait Cancer Control Centre, Department of Nuclear Medicine, Shwiekh (Kuwait); Bradley, D., E-mail: malkhorayef@ksu.edu.sa [University of Surrey, Centre for Nuclear and Radiation Physics, Guildford, Surrey, GU2 7XH (United Kingdom)

    2016-10-15

    A pacemaker, which is used for heart re synchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of the pacemaker implantation procedures increased 50% worldwide. During this procedure, patients and staff can be exposed to excessive radiation exposure. Wide range of doses was reported in previous studies, suggesting that optimization of this procedure is not fulfilled yet. This study aims to evaluate the patient and staff radiation doses during cardiac pacemaker procedure and quantify the patient effective dose. A total of 145 procedures were performed for five pacemakers procedures (VVI, VVIR, VVD, VVDR and DDDR) two hospitals were evaluated. Patients doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from National Radiological Protection Board. The effective dose values were used to estimate the cancer risk from pacemaker procedure. Patients demographic data, exposure parameters for both fluoroscopy and radiography were quantified. The mean patients doses (Gy. cm{sup 2}) for VVI, VVIR, VVD, VVDR and DDDR was 1.52±0.13 (1.43-1.61), 3.28±2.34 (0.29-8.73), 3.04±1.67 (1.57-4.86), 6.04±2.326 and 19.2±3.6 (5.43-30.2), respectively, per procedure. The overall patients effective dose is 1.1 mSv per procedure. (Author)

  2. Safety of Laser Interstitial Thermal Therapy in Patients With Pacemakers.

    Science.gov (United States)

    Grewal, Sanjeet S; Gorny, Krzysztof R; Favazza, Christopher P; Watson, Robert E; Kaufmann, Timothy J; Van Gompel, Jamie J

    2018-02-10

    Laser interstitial thermal therapy (LiTT) has increasingly been used as a treatment option for medically refractory epilepsy, tumors, and radiation necrosis. The use of LiTT requires intraoperative magnetic resonance (MR) thermography. This can become an issue in patients with other implanted therapeutic devices such as pacemakers and vagal nerve stimulators due to concerns regarding increases in the specific absorption rate (SAR). This is a technical case report demonstrating a successfully and safely performed LiTT in a 1.5-T magnetic resonance imaging (MRI) in a patient with a pacemaker for mesial temporal sclerosis. An 83-yr-old gentleman who had an implanted cardiac pacemaker presented with medically intractable epilepsy and was confirmed to have mesial temporal sclerosis on imaging. Video electroencephalography demonstrated concordant ipsilateral seizures and semiology. He underwent LiTT for ablation of the mesial temporal lobe. This was performed with the below described protocol with a cardiology nurse monitoring the patient's cardiac condition and a physicist monitoring SAR, and MR imaging quality without any adverse events. This study reports on a protocol of cardiac and MR SAR to safely perform MR-guided LiTT in the setting of traditional pacemakers in patients who are not pacemaker dependent. Copyright © 2018 by the Congress of Neurological Surgeons

  3. Sacral Neuromodulation in Patients With a Cardiac Pacemaker

    Directory of Open Access Journals (Sweden)

    Abdullah A. Gahzi

    2016-09-01

    Full Text Available The objective of this study was to describe our experience using sacral neuromodulation to treat urinary urgency, frequency, urge incontinence, and chronic urinary retention in patients with cardiac pacemakers. With the increasingly widespread use of InterStim for bladder function restoration, we are seeing more complex patients with multiple comorbidities, including cardiac conditions. Herein, we report 3 cases of individuals with cardiac pacemakers who underwent InterStim implantation to treat urinary conditions. This study is a case series of 3 patients with cardiac pacemakers who underwent sacral neuromodulation to treat refractory voiding dysfunction. The initial patient screening for InterStim therapy involved percutaneous nerve evaluation (PNE, in which a temporary untined lead wire was placed through the S3 foramen. Patients who did not respond to PNE proceeded to a staged implant. All patients in this study had a greater than 50% improvement of their urinary symptoms during the initial trial and underwent placement of the InterStim implantable pulse generator (IPG. Postoperative programming was done under electrocardiogram monitoring by a cardiologist. No interference was observed between the Inter-Stim IPG and the cardiac pacemaker. In this group of patients, sacral neuromodulation in the presence of a cardiac pacemaker appears to have been safe.

  4. Patients exposure from fluoroscopic guided pacemaker implantation procedures

    International Nuclear Information System (INIS)

    Alkhorayef, M.; Babikir, E.; Sulieman, A.; Daar, E.; Alnaaimi, M.; Alduaij, M.; Bradley, D.

    2016-10-01

    A pacemaker, which is used for heart re synchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of the pacemaker implantation procedures increased 50% worldwide. During this procedure, patients and staff can be exposed to excessive radiation exposure. Wide range of doses was reported in previous studies, suggesting that optimization of this procedure is not fulfilled yet. This study aims to evaluate the patient and staff radiation doses during cardiac pacemaker procedure and quantify the patient effective dose. A total of 145 procedures were performed for five pacemakers procedures (VVI, VVIR, VVD, VVDR and DDDR) two hospitals were evaluated. Patients doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from National Radiological Protection Board. The effective dose values were used to estimate the cancer risk from pacemaker procedure. Patients demographic data, exposure parameters for both fluoroscopy and radiography were quantified. The mean patients doses (Gy. cm 2 ) for VVI, VVIR, VVD, VVDR and DDDR was 1.52±0.13 (1.43-1.61), 3.28±2.34 (0.29-8.73), 3.04±1.67 (1.57-4.86), 6.04±2.326 and 19.2±3.6 (5.43-30.2), respectively, per procedure. The overall patients effective dose is 1.1 mSv per procedure. (Author)

  5. Implantable Cardiac Pacemakers – 50 Years from the First Implantation

    Directory of Open Access Journals (Sweden)

    Ratko Magjarević

    2010-01-01

    Overview: Development of implantable cardiac pacemaker was enabled by another important invention, the silicon transistor. h ough the invention of suitable lithium cells as appropriate power supply was essential for prolongation of battery life cycle and for increased reliability of pacemakers, main milestones in the development were associated with technological breakthroughs in electronics: from transistors, which introduced such features as small size and low power consumption, to hybrid and integrated circuits, which enabled programmability, microprocessors, which added more options in programming (multiprogrammability, diagnostics and telemetry, and the ICT (information communication technology that enabled physicians remote access to patients and interrogation of their implantable devices. Conclusions: Implantable pacemakers are reliable devices indicated for a wide range of dif erent therapies of cardiac rhythm disorders and heart failure. h ere is still a lot to learn about the physiology of a normal heart and even more about the failing heart. Modern pacemakers provide physicians valuable information from pacemakers’ memory via the built-in telemetry system. h ese information help physicians to better understand pathologic processes within the heart, thus contributing to the development of new ideas for treatment of diseases and for precise tailoring of the therapy to the patient’s needs. Although implantable pacemakers have reached the level of mature technology, they will continue to develop with therapies and diagnostics to facilitate a higher quality of life.

  6. Pacemaker lead fracture associated with weightlifting: a report of two cases.

    Science.gov (United States)

    Deering, J A; Pederson, D N

    1993-12-01

    Two cases of pacemaker lead fracture associated with weight-lifting are presented. This is a rare association which has only recently been described in the literature. In both cases, the pacemaker lead was fractured between the clavicle and the first rib, suggesting crush injury. The chest X-ray, pacemaker telemetry with measurement of lead impedance, and pacemaker reprogramming were all helpful in management.

  7. Contribution of small conductance K+ channels to sinoatrial node pacemaker activity: insights from atrial-specific Na+ /Ca2+ exchange knockout mice.

    Science.gov (United States)

    Torrente, Angelo G; Zhang, Rui; Wang, Heidi; Zaini, Audrey; Kim, Brian; Yue, Xin; Philipson, Kenneth D; Goldhaber, Joshua I

    2017-06-15

    Repolarizing currents through K + channels are essential for proper sinoatrial node (SAN) pacemaking, but the influence of intracellular Ca 2+ on repolarization in the SAN is uncertain. We identified all three isoforms of Ca 2+ -activated small conductance K + (SK) channels in the murine SAN. SK channel blockade slows repolarization and subsequent depolarization of SAN cells. In the atrial-specific Na + /Ca 2+ exchanger (NCX) knockout mouse, cellular Ca 2+ accumulation during spontaneous SAN pacemaker activity produces intermittent hyperactivation of SK channels, leading to arrhythmic pauses alternating with bursts of pacing. These findings suggest that Ca 2+ -sensitive SK channels can translate changes in cellular Ca 2+ into a repolarizing current capable of modulating pacemaking. SK channels are a potential pharmacological target for modulating SAN rate or treating SAN dysfunction, particularly under conditions characterized by abnormal increases in diastolic Ca 2+ . Small conductance K + (SK) channels have been implicated as modulators of spontaneous depolarization and electrical conduction that may be involved in cardiac arrhythmia. However, neither their presence nor their contribution to sinoatrial node (SAN) pacemaker activity has been investigated. Using quantitative PCR (q-PCR), immunostaining and patch clamp recordings of membrane current and voltage, we identified all three SK isoforms (SK1, SK2 and SK3) in mouse SAN. Inhibition of SK channels with the specific blocker apamin prolonged action potentials (APs) in isolated SAN cells. Apamin also slowed diastolic depolarization and reduced pacemaker rate in isolated SAN cells and intact tissue. We investigated whether the Ca 2+ -sensitive nature of SK channels could explain arrhythmic SAN pacemaker activity in the atrial-specific Na + /Ca 2+ exchange (NCX) knockout (KO) mouse, a model of cellular Ca 2+ overload. SAN cells isolated from the NCX KO exhibited higher SK current than wildtype (WT) and apamin

  8. [TRENDS OF PERMANENT PACEMAKER IMPLANTATION IN A SINGLE CENTER OVER A 20-YEAR PERIOD].

    Science.gov (United States)

    Antonelli, Dante; Ilan, Limor Bushar; Freedberg, Nahum A; Feldman, Alexander; Turgeman, Yoav

    2015-05-01

    To review the changes in permanent pacemaker implantation indications, pacing modes and patients' demographics over a 20-year period. We retrospectively retrieved data on patients who underwent first implantation of the pacemaker between 1-1-1991 and 31-12-2010. One thousand and nine (1,009) patients underwent a first pacemaker implantation during that period; 535 were men (53%), their mean age was 74.6±19.5 years; the highest rate of implanted pacemaker was in patients ranging in age from 70-79 years, however there was an increasing number of patients aged over 80 years. The median survival time after initial pacemaker implantation was 8 years. Syncope was the most common symptom (62.5%) and atrioventricular block was the most common electrocardiographic indication (56.4%) leading to pacemaker implantation. There was increased utilization of dual chamber and rate responsive pacemakers over the years. There was no difference regarding mode selection between genders. Pacemaker implantation rates have increased over a 20-year period. Dual chamber replaced most of the single ventricular chamber pacemaker and rate responsive pacemakers became the norm. The data of a small volume center are similar to those reported in pacemaker surveys of high volume pacemaker implantation centers. They confirm adherence to the published guidelines for pacing.

  9. Radioisotope-powered cardiac pacemaker program. Clinical studies of the nuclear pacemaker model NU-5. Final report

    International Nuclear Information System (INIS)

    1980-06-01

    Beginning in February, 1970, the Nuclear Materials and Equipment Corporation (NUMEC) undertook a program to design, develop and manufacture a radioisotope powered cardiac pacemaker system. The scope of technical work was specified to be: establish system, component, and process cost reduction goals using the prototype Radioisotope Powered Cardiac Pacemaker (RCP) design and develop production techniques to achieve these cost reduction objectives; fabricate radioisotope powered fueled prototype cardiac pacemakers (RCP's) on a pilot production basis; conduct liaison with a Government-designated fueling facility for purposes of defining fueling requirements, fabrication and encapsulation procedures, safety design criteria and quality control and inspection requirements; develop and implement Quality Assurance and Reliability Programs; conduct performance, acceptance, lifetime and reliability tests of fueled RCP's in the laboratory; conduct liaison with the National Institutes of Health and with Government specified medical research institutions selected for the purpose of undertaking clinical evaluation of the RCP in humans; monitor and evaluate, on a continuing basis, all test data; and perform necessary safety analyses and tests. Pacemaker designs were developed and quality assurance and manufacturing procedures established. Prototype pacemakers were fabricated. A total of 126 radioisotope powered units were implanted and have been followed clinically for approximately seven years. Four (4) of these units have failed. Eighty-three (83) units remain implanted and satisfactorily operational. An overall failure rate of less than the target 0.15% per month has been achieved

  10. Ductal carcinoma of the breast in the pacemaker generator's pocket.

    Science.gov (United States)

    Zonca, P; Herokova, J; Cambal, M; Jacobi, C A

    2009-01-01

    Authors present a case of a 78-year-old female patient with invasive ductal adenocarcinoma in the pacemaker, s pocket. A decubitus-like tumor had developed in this place, and has been missinterpretated as a benign lesion for 5 months. Diagnosis was done with a time delay. An excisional biopsy revealed annvasive ductal adenocarcinoma. The first step was the implantation of a new pacemaker generator performed on the opposite side. The second step was a modified radical mastectomy, according to Madden, and the removal of the originally implanted pacemaker generator. Radiotherapy and hormonal adjuvant therapy were applied after surgery. The patient was followed-up at an out-patient clinic, and died 25 months after diagnosis because of generalization of the disease (Fig. 2, Ref. 35). Full Text (Free, PDF) www.bmj.sk.

  11. Types of Bipolar Disorder

    Science.gov (United States)

    ... Events Home Science News Meetings and Events Multimedia Social Media Press Resources Newsletters NIMH News Feeds About Us ... has a lot of money, or has special powers. Someone having psychotic symptoms ... Substance Abuse: People with bipolar disorder may also misuse alcohol ...

  12. Discrete bipolar universal integrals

    Czech Academy of Sciences Publication Activity Database

    Greco, S.; Mesiar, Radko; Rindone, F.

    2014-01-01

    Roč. 252, č. 1 (2014), s. 55-65 ISSN 0165-0114 R&D Projects: GA ČR GAP402/11/0378 Institutional support: RVO:67985556 Keywords : bipolar integral * universal integral * Choquet integral Subject RIV: BA - General Mathematics Impact factor: 1.986, year: 2014 http://library.utia.cas.cz/separaty/2014/E/mesiar-0432224.pdf

  13. El trastorno bipolar

    OpenAIRE

    Freaza Rodríguez, Paula

    2014-01-01

    Se exponen los aspectos más relevantes del trastorno bipolar, entender qué significa este concepto, conocer los tipos que existen, qué otros trastornos suelen aparecer al mismo tiempo y qué tratamientos son los que dan mejores resultados

  14. Global health resource utilization associated with pacemaker complications.

    Science.gov (United States)

    Waweru, Catherine; Steenrod, Anna; Wolff, Claudia; Eggington, Simon; Wright, David Jay; Wyrwich, Kathleen W

    2017-07-01

    To estimate health resource utilization (HRU) associated with the management of pacemaker complications in various healthcare systems. Electrophysiologists (EPs) from four geographical regions (Western Europe, Australia, Japan, and North America) were invited to participate. Survey questions focused on HRU in the management of three chronic pacemaker complications (i.e. pacemaker infections requiring extraction, lead fractures/insulation breaches requiring replacement, and upper extremity deep venous thrombosis [DVT]). Panelists completed a maximum of two web-based surveys (iterative rounds). Mean, median values, and interquartile ranges were calculated and used to establish consensus. Overall, 32 and 29 panelists participated in the first and second rounds of the Delphi panel, respectively. Consensus was reached on treatment and HRU associated with a typical pacemaker implantation and complications. HRU was similar across regions, except for Japan, where panelists reported the longest duration of hospital stay in all scenarios. Infections were the most resource-intensive complications and were characterized by intravenous antibiotics days of 9.6?13.5 days and 21.3?29.2 days for pocket and lead infections respectively; laboratory and diagnostic tests, and system extraction and replacement procedures. DVT, on the other hand, was the least resource intensive complication. The results of the panel represent the views of the respondents who participated and may not be generalizable outside of this panel. The surveys were limited in scope and, therefore, did not include questions on management of acute complications (e.g. hematoma, pneumothorax). The Delphi technique provided a reliable and efficient approach to estimating resource utilization associated with chronic pacemaker complications. Estimates from the Delphi panel can be used to generate costs of pacemaker complications in various regions.

  15. Experimental evidence of a chaotic region in a neural pacemaker

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Hua-Guang, E-mail: guhuaguang@tongji.edu.cn [School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China); Department of Electronic Engineering, City University of Hong Kong, Hong Kong SAR (China); Jia, Bing [School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China); Chen, Guan-Rong [Department of Electronic Engineering, City University of Hong Kong, Hong Kong SAR (China)

    2013-03-15

    In this Letter, we report the finding of period-adding scenarios with chaos in firing patterns, observed in biological experiments on a neural pacemaker, with fixed extra-cellular potassium concentration at different levels and taken extra-cellular calcium concentration as the bifurcation parameter. The experimental bifurcations in the two-dimensional parameter space demonstrate the existence of a chaotic region interwoven with the periodic region thereby forming a period-adding sequence with chaos. The behavior of the pacemaker in this region is qualitatively similar to that of the Hindmarsh–Rose neuron model in a well-known comb-shaped chaotic region in two-dimensional parameter spaces.

  16. [Management of surgery patients with implanted cardiac pacemakers].

    Science.gov (United States)

    Ugljen, R; Dadić, D; Ferek-Petrić, B; Jelić, I; Letica, D; Anić, D; Husar, J

    1995-01-01

    Patients having cardiac pacemaker implanted may be subjected to various general surgery procedures. Application of electrosurgery for the purpose of resection and coagulation, provides a high frequency electric field which produces electric voltage on the electrodes of the pacing system. This voltage may be detected within the pacing system, and various arrhythmias can be provoked in correlation with underlying rhythm and mode of pacing. Preoperative patient control and proper pacemaker programming can prevent the pacing malfunctions due to the electrosurgery application. Appropriate positioning of the neutral electrode in relation to the pacing system avoids the electric fields intersection and decreases their interference.

  17. A leadless pacemaker in the real-world setting

    DEFF Research Database (Denmark)

    Roberts, Paul R.; Clementy, Nicolas; Al Samadi, Faisal

    2017-01-01

    , telemetry, and battery issues. Objective The acute performance of the Micra transcatheter pacemaker from a worldwide Post-Approval Registry is reported. Methods The registry is an ongoing prospective single-arm observational study designed to assess the safety and effectiveness of Micra in the post...... were low and stable. Conclusion Performance of the Micra transcatheter pacemaker in a real-world setting demonstrates a high rate (99.6%) of implant success and low rate (1.51%) of major complications through 30 days post implant. In particular, the rates of pericardial effusion, device dislodgement...

  18. ON BIPOLAR SINGLE VALUED NEUTROSOPHIC GRAPHS

    OpenAIRE

    Said Broumi; Mohamed Talea; Assia Bakali; Florentin Smarandache

    2016-01-01

    In this article, we combine the concept of bipolar neutrosophic set and graph theory. We introduce the notions of bipolar single valued neutrosophic graphs, strong bipolar single valued neutrosophic graphs, complete bipolar single valued neutrosophic graphs, regular bipolar single valued neutrosophic graphs and investigate some of their related properties.

  19. Bipolar disorder and dementia: where is the link?

    Science.gov (United States)

    Masouy, Anaïs; Chopard, Gilles; Vandel, Pierre; Magnin, Eloi; Rumbach, Lucien; Sechter, Daniel; Haffen, Emmanuel

    2011-03-01

    Cognitive disorders appearing in the course of bipolar disease have been identified, and recent studies have defined the neuropsychological characteristics of this pathology, which includes attention, executive function, memory and language disorders. However, questions remain concerning the appearance of dementia symptoms over the course of bipolar disorder in certain patients: is it a chance association or is there a connection between bipolar disorders and dementia? If the latter hypothesis is considered, what is the nature of the dementia, which might be considered as a dementia specific to bipolar disorder? Current clinical, neuropsychological and cerebral imaging data are inconclusive, but similarities with frontotemporal dementia might be highlighted. Functional imaging studies might provide answers as well as more specific tests in neuropsychology. The cause of cognitive damage in bipolar disease also raises questions concerning a neurodevelopmental or neurodegenerative process, because several factors seem to influence cognition and these two processes might occur simultaneously. Long-term studies are necessary to determine whether cognitive deterioration in bipolar disease is stable or progressive. There might also be different neurobiological subgroups of patients with bipolar disease. © 2011 The Authors. Psychogeriatrics © 2011 Japanese Psychogeriatric Society.

  20. Abordagens psicoterápicas no transtorno bipolar Psychoterapeutic approach in bipolar disorder

    Directory of Open Access Journals (Sweden)

    Paulo Knapp

    2005-01-01

    Full Text Available Embora o tratamento farmacológico seja essencial para o tratamento do transtorno bipolar, apenas 40% de todos os pacientes que aderem às medicações permanecem assintomáticos durante o período de seguimento, o que tem levado ao desenvolvimento de intervenções psicoterápicas associadas. O objetivo deste artigo é examinar as evidências atuais da eficácia de intervenções psicoterápicas no tratamento do transtorno bipolar. Foi realizada uma pesquisa bibliográfica por meio do MedLine, PsychoINFO, Lilacs e Cochrane Data Bank, até o ano de 2004, em que foram procurados artigos originais e revisões sobre as abordagens psicoterápicas utilizadas no tratamento do transtorno bipolar. Há várias abordagens que podem se mostrar úteis no tratamento do transtorno bipolar. A psicoeducação e a terapia cognitivo-comportamental apresentam as evidências mais consistentes e são as técnicas mais amplamente estudadas. As intervenções envolvendo familiares e a terapia interpessoal e de ritmo social se mostram tratamentos eficazes em determinadas situações. Há alguns estudos empregando a terapia psicodinâmica no transtorno bipolar, mas são estudos com limitações metodológicas. Apesar de haver evidências demonstrando a eficácia de determinadas abordagens psicoterápicas no transtorno bipolar, ainda é necessária a realização de estudos posteriores que comprovem tais dados e que desenvolvam tratamentos baseados em modelos etiológicos e que identifiquem tratamentos específicos para as diferentes fases e tipos de transtorno bipolar.Although pharmacological treatment is essential for treating bipolar disorder, less than half of all medication compliant patients are non-symptomatic during follow-up, which has led to developments of adjunctive psychosocial interventions. This paper examines the current evidence for effectiveness of psychotherapeutic interventions in the treatment of bipolar disorder. Searches were undertaken through Med

  1. Transcatheter leadless pacemaker implantation in a patient with a transvenous dual-chamber pacemaker already in place.

    Science.gov (United States)

    Karjalainen, Pasi P; Nammas, Wail; Paana, Tuomas

    2016-01-01

    An 83-year-old lady had a DDDR pacemaker inserted in 1997 for symptomatic atrioventricular block. She underwent battery replacement in 2008. In 2010, she developed atrial fibrillation; the pacemaker was switched to VVIR mode. During the last 2years, ventricular lead threshold increased progressively. In December 2015, she presented for elective battery replacement. After successful battery replacement, the ventricular lead threshold remained high; therefore, we implanted a leadless transcatheter pacemaker, via femoral vein access, using a dedicated catheter delivery system. Electrical measurements at this stage revealed a pacing threshold of 0.28V at 0.24msec, and an impedance of 650Ω. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Relationship between Childhood Maltreatment, Suicidality, and Bipolarity: A Retrospective Study

    OpenAIRE

    Park, Young-Min

    2017-01-01

    Objective The aims of current study were to determine whether childhood maltreatment contributes to the occurrence of major depressive disorder (MDD) with bipolarity or suicidality. Methods In total, 132 outpatients diagnosed with MDD between 2014 and 2015 on the medical records were included. The subjects were divided into two groups according to the presence of childhood maltreatment (CM group) and no childhood maltreatment (NCM group). Depression severity and bipolarity were identified usi...

  3. Discuss the cause and treatment of pacemaker lead dislocation and deal with

    International Nuclear Information System (INIS)

    Chen Yueguang; Zhang Dadong; Lu Jie; Yang Hui; Liu Chunyan; Zhang Wei

    2003-01-01

    Objective: To follow up the patients with pacemaker, observe the condition of pacemaker lead, to explore the cause of lead dislocation, to find out and prevent its occurrence. Methods: Summarizing the clinical data of 6 patients with pacemaker, 7 pacemaker leads with 8 time dislocation, pacemaker 2 DDDR, 2 DDD, 2 VVI. Results: Four patients were punctured from right subclavian vein, one from left subclavian vein and one from right brachiocephalic vein; four leads were dislocation in atrium and one mildly dislocation; four leads dislocation in ventricle and two mildly dislocation; There were 3 old women with 4 leads and 5 times of dislocation

  4. [Pediatric bipolar disorder - case report of a bipolar patient with disease onset in childhood and adolescence: implications for diagnosis and therapy].

    Science.gov (United States)

    Lackner, N; Birner, A; Bengesser, S A; Reininghaus, B; Kapfhammer, H P; Reininghaus, E

    2014-11-01

    In recent years, intense controversies have evolved about the existence and exact diagnostic criteria of pediatric bipolar affective disorder. The present study aims to discuss pediatric bipolar affective disorder based on the current literature focussing on the diagnostic prospects. Based on a case study, a process of bipolar disorder developed in childhood is depicted exemplarily. Because of the high comorbidity and overlapping symptoms of paediatric bipolar affective disorder and other psychiatric disorders, the major impact of the differential diagnosis has to be stressed. An early diagnosis and the treatment possibilities are discussed. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Genetic utility of broadly defined bipolar schizoaffective disorder as a diagnostic concept

    Science.gov (United States)

    Hamshere, M. L.; Green, E. K.; Jones, I. R.; Jones, L.; Moskvina, V.; Kirov, G.; Grozeva, D.; Nikolov, I.; Vukcevic, D.; Caesar, S.; Gordon-Smith, K.; Fraser, C.; Russell, E.; Breen, G.; St Clair, D.; Collier, D. A.; Young, A. H.; Ferrier, I. N.; Farmer, A.; McGuffin, P.; Holmans, P. A.; Owen, M. J.; O’Donovan, M. C.; Craddock, N.

    2009-01-01

    Background Psychiatric phenotypes are currently defined according to sets of descriptive criteria. Although many of these phenotypes are heritable, it would be useful to know whether any of the various diagnostic categories in current use identify cases that are particularly helpful for biological–genetic research. Aims To use genome-wide genetic association data to explore the relative genetic utility of seven different descriptive operational diagnostic categories relevant to bipolar illness within a large UK case–control bipolar disorder sample. Method We analysed our previously published Wellcome Trust Case Control Consortium (WTCCC) bipolar disorder genome-wide association data-set, comprising 1868 individuals with bipolar disorder and 2938 controls genotyped for 276 122 single nucleotide polymorphisms (SNPs) that met stringent criteria for genotype quality. For each SNP we performed a test of association (bipolar disorder group v. control group) and used the number of associated independent SNPs statistically significant at Pschizoaffective disorder, bipolar type; DSM–IV: bipolar I disorder; bipolar II disorder; schizoaffective disorder, bipolar type. Results The RDC schizoaffective disorder, bipolar type (v. controls) stood out from the other diagnostic subsets as having a significant excess of independent association signals (Pschizoaffective features have either a particularly strong genetic contribution or that, as a group, are genetically more homogeneous than the other phenotypes tested. The results point to the importance of using diagnostic approaches that recognise this group of individuals. Our approach can be applied to similar data-sets for other psychiatric and non-psychiatric phenotypes. PMID:19567891

  6. Life expectancy in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2015-01-01

    OBJECTIVE: Life expectancy in patients with bipolar disorder has been reported to be decreased by 11 to 20 years. These calculations are based on data for individuals at the age of 15 years. However, this may be misleading for patients with bipolar disorder in general as most patients have a later...... onset of illness. The aim of the present study was to calculate the remaining life expectancy for patients of different ages with a diagnosis of bipolar disorder. METHODS: Using nationwide registers of all inpatient and outpatient contacts to all psychiatric hospitals in Denmark from 1970 to 2012 we...... remaining life expectancy in bipolar disorder and that of the general population decreased with age, indicating that patients with bipolar disorder start losing life-years during early and mid-adulthood. CONCLUSIONS: Life expectancy in bipolar disorder is decreased substantially, but less so than previously...

  7. Regulation of basal and reserve cardiac pacemaker function by interactions of cAMP mediated PKA-dependent Ca2+ cycling with surface membrane channels

    Science.gov (United States)

    Vinogradova, Tatiana M.; Lakatta, Edward G.

    2009-01-01

    Decades of intensive research of primary cardiac pacemaker, the sinoatrial node, have established potential roles of specific membrane channels in the generation of the diastolic depolarization, the major mechanism allowing sinoatrial node cells generate spontaneous beating. During the last three decades, multiple studies made either in the isolated sinoatrial node or sinoatrial node cells have demonstrated a pivotal role of Ca2+ and, specifically Ca2+-release from sarcoplasmic reticulum, for spontaneous beating of cardiac pacemaker. Recently, spontaneous, rhythmic local subsarcolemmal Ca2+ releases from ryanodine receptors during late half of the diastolic depolarization have been implicated as a vital factor in the generation of sinoatrial node cells spontaneous firing. Local Ca2+ releases are driven by a unique combination of high basal cAMP production by adenylyl cyclases, high basal cAMP degradation by phosphodiesterases and a high level of cAMP-mediated PKA-dependent phosphorylation. These local Ca2+ releases activate an inward Na+-Ca2+ exchange current which accelerates the terminal diastolic depolarization rate and, thus, controls the spontaneous pacemaker firing. Both the basal primary pacemaker beating rate and its modulation via β-adrenergic receptor stimulation appear to be critically dependent upon intact RyR function and local subsarcolemmal sarcoplasmic reticulum generated Ca2+ releases. This review aspires to integrate the traditional viewpoint that has emphasized the supremacy of the ensemble of surface membrane ion channels in spontaneous firing of the primary cardiac pacemaker, and these novel perspectives of cAMP-mediated PKA-dependent Ca2+ cycling in regulation of the heart pacemaker clock, both in the basal state and during β-adrenergic receptor stimulation. PMID:19573534

  8. [Bipolar disorder in adolescence].

    Science.gov (United States)

    Brunelle, Julie; Milhet, Vanessa; Consoli, Angèle; Cohen, David

    2014-04-01

    Juvenile mania is a concept widely developed but also highly debated since the 1990s. In the heart of this debate, Severe Mood Dysregulation (SMD) and "Temper Dysregulation disorder with Dysphoria" (recently integrated in DSM-5) showed their interest. Actually, the objective is to distinguish two clinical phenotypes in order to avoid confusion between (1) what would raise more of mood dysregulation with chronic manic like symptoms, and (2) bipolar disorder type I with episodic and acute manic episodes. Therapeutic stakes are major. In adolescents, even if DSM adult diagnostic criteria can be used and bipolar disorder type I clearly established, differential diagnostic at onset between acute manic episode and schizophrenia onset remain sometimes difficult to assess. Furthermore, it is crucial to better assess outcome of these adolescents, in terms of morbidity and potential prognosis factors, knowing that a younger age at onset is associated with a poorer outcome according to several adult studies. Therapeutic implications could then be drawn.

  9. Depressive and bipolar disorders

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Hansen, Hanne Vibe; Demyttenaere, Koen

    2005-01-01

    of the patients (40-80%) had erroneous views as to the effect of antidepressants. Older patients (over 40 years of age) consistently had a more negative view of the doctor-patient relationship, more erroneous ideas concerning the effect of antidepressants and a more negative view of antidepressants in general....... Moreover, their partners agreed on these negative views. Women had a more negative view of the doctor-patient relationship than men, and patients with a depressive disorder had a more negative view of antidepressants than patients with bipolar disorder. The number of psychiatric hospitalizations......BACKGROUND: There is increasing evidence that attitudes and beliefs are important in predicting adherence to treatment and medication in depressive and bipolar disorders. However, these attitudes have received little study in patients whose disorders were sufficiently severe to require...

  10. Deactivation of Pacemaker: Ethical Approach or Managerial Failure?

    Directory of Open Access Journals (Sweden)

    Macková Marie

    2017-12-01

    Full Text Available The decision about the deactivation of a pacemaker must be the result of a multicriteria decision-making process where the legal, ethical and effectiveness aspects must be taken into account and delicately balanced, while also considering the risk of managerial failure. Academic as well as professional discussion is necessary because there is a whole range of question marks on this topic and all the aspects mentioned above. The aim of this paper is to contribute to the debate by presenting the views of Czech physicians about the possibility of deactivation of the pacemaker in patients in terminal states. Based on the results of our research, the following steps are recommended to enable the deactivation of pacemakers in the Czech environment. Before the patient’s own indication of pacemaker therapy, treatment should be discussed with the patient in detail, including complications and deactivation options. Czech ethical consultant services should be set up in Czech hospitals. And last but not least, they should take an opinion on this issue as well as the professional society.

  11. Pacemaker dislocation - Truly ectopic activation necessitating surgical treatment

    NARCIS (Netherlands)

    de Kroon, TL; Witsenburg, M; Bogerts, AJJC

    Intra-abdominal migration of a generator from an epicardial pacemaker system is a rare but potentially life-threatening complication. We report on a case of a 2-year-old child in whom the generator silently migrated from the sheath of the rectus abdominis muscle in the upper abdominal wall down into

  12. Neutron spectra from radionuclide sources for cardiac pacemakers

    International Nuclear Information System (INIS)

    Kluge, H.

    1975-01-01

    Neutron spectra from Plutonium 238 radioisotope batteries powering cardiac pacemakers are measured in the energy range above 0.7 MeV. The results are used to calculate radiation doses within a cylindrical phantom. There are only minor differences between the different types of plutonium 238-batteries and californium 252-batteries

  13. Prophylactic antibiotic for pacemaker surgery: what is optimal ...

    African Journals Online (AJOL)

    One of them, a bed-ridden patient developed severe pocket infection necessitating explantation and replacement 3 weeks later. Conclusions: We noted with satisfaction that short regime of prophylactic parentral ceftriaxone is effective in preventing pacemaker infection and there is no need for the long regimen. Niger Med J.

  14. 238Pu sources for cardiac pacemakers. II. Control

    International Nuclear Information System (INIS)

    Pottier, R.; Merigot, S.

    1976-01-01

    The method and the apparatus used for thermal (power) and radioactive control of radioisotopic sources for pacemakers are briefly described. The cybernetic system is also presented, which assumes almost automatically the monitoring of control, mechanical and electronic works, data processing, the measurements and computations, and the works related to quality control [fr

  15. Cost Issues in Pacemaker Surgery in Nigeria | Thomas | Nigerian ...

    African Journals Online (AJOL)

    Permanent pacemakers are being implanted worldwide for prolongation and improvement of lives of patients who have conduction defects. Even though the average cost of pacing has reduced significantly over the years, procurement of the all important treatment modality remains a major financial drain especially in a ...

  16. [Aspergillus fumigatus endocarditis in a patient with a biventricular pacemaker].

    Science.gov (United States)

    Cuesta, José M; Fariñas, María C; Rodilla, Irene G; Salesa, Ricardo; de Berrazueta, José R

    2005-05-01

    Aspergillus fumigatus endocarditis is one of the rarest and severest complications in cardiological patients. We describe a patient with an intracardial pacemaker who was diagnosed as having Aspergillus fumigatus endocarditis. Postmortem examination showed a large, Aspergillus-infected thrombus encased in the right ventricle, pulmonary trunk and main pulmonary branches.

  17. Hemodynamic instability after pulmonary veins isolation in a patient with dual chamber pacemaker: The phantom injury of the ventricular lead.

    Science.gov (United States)

    Kiuchi, Márcio Galindo; Lobato, Guilherme Miglioli; Chen, Shaojie

    2017-06-01

    The standard treatment of sinus node dysfunction (SND) is the pacemaker implantation, and the ideal methodology for the management of atrial fibrillation (AF) is rhythm control, but this is sometimes very hard to accomplish. For such actions, complete isolation of all pulmonary veins (PVI) is currently widely accepted as the best endpoint. In this case, we report a female patient, 81 years old, with controlled hypertension, without coronary artery disease, bearer of bilateral knee replacement, and dual chamber pacemaker implanted 1.5 years ago owing to sinus node disease, presenting the following symptoms: presyncope episodes associated with sustained irregular palpitation tachycardia. The evaluation of the pacemaker-recorded episodes of atrial fibrillation, the echocardiogram-presented normal systolic function and measurements, as well as the resting myocardial scintigraphy and with drug use did not demonstrate ischemia and/or fibrosis. The patient was in use of valsartan 320 mg daily, amlodipine 10 mg daily, sotalol hydrochloride 120 mg 2 times daily, and dabigatran 110 mg 2 times daily. At the end of the PVI, the patient presented hemodynamic instability, with a decrease in heart rate to 30 bpm and invasive arterial blood pressure to 60/30 mmHg. The pericardial puncture was quickly carried out with the possibility of cardiac tamponade as the first hypothesis, but no pericardial effusion was found. Next, we detected acute capture loss from the ventricular pacemaker lead, unvarying with high voltage and pulse width, even with stable impedance, sense and keeping the same position visualized by fluoroscopy. And there was soon afterwards induction of sustained ventricular tachycardia degenerating to spontaneous ventricular fibrillation. Electrical cardioversion-defibrillation was performed with 200J, and the sinus rhythm was reestablished, but there was a dead short, and the pacemaker generator was burned and disabled. So, we can speculate that

  18. Cognitive processes and attitudes in bipolar disorder: A study into personality, dysfunctional attitudes and attention bias in patients with bipolar disorder and their relatives

    NARCIS (Netherlands)

    Jabben, N.E.J.G.; Arts, B.; Jongen, E.M.M.; Smulders, F.T.Y.; van Os, J.; Krabbendam, L.

    2012-01-01

    Background: Research in cognitive processes and attitudes in bipolar disorder is scarce and has provided mixed findings, possibly due to differences in current mood state. It is unclear whether alterations in cognitive processes and attitudes are only related to the depressive mood states of bipolar

  19. [Creativity and bipolar disorder].

    Science.gov (United States)

    Maçkalı, Zeynep; Gülöksüz, Sinan; Oral, Timuçin

    2014-01-01

    The relationship between creativity and bipolar disorder has been an intriguing topic since ancient times. Early studies focused on describing characteristics of creative people. From the last quarter of the twentieth century, researchers began to focus on the relationship between mood disorders and creativity. Initially, the studies were based on biographical texts and the obtained results indicated a relationship between these two concepts. The limitations of the retrospective studies led the researchers to develop systematic investigations into this area. The systematic studies that have focused on artistic creativity have examined both the prevalence of mood disorders and the creative process. In addition, a group of researchers addressed the relationship in terms of affective temperaments. Through the end of the 90's, the scope of creativity was widened and the notion of everyday creativity was proposed. The emergence of this notion led researchers to investigate the associations of the creative process in ordinary (non-artist) individuals. In this review, the descriptions of creativity and creative process are mentioned. Also, the creative process is addressed with regards to bipolar disorder. Then, the relationship between creativity and bipolar disorder are evaluated in terms of aforementioned studies (biographical, systematic, psychobiographical, affective temperaments). In addition, a new model, the "Shared Vulnerability Model" which was developed to explain the relationship between creativity and psychopathology is introduced. Finally, the methodological limitations and the suggestions for resolving these limitations are included.

  20. The continuum between Bipolar Disorder and Borderline Personality Disorder.

    Science.gov (United States)

    Elisei, Sandro; Anastasi, Serena; Verdolini, Norma

    2012-09-01

    Several studies have been carried out regarding the possible overlap between Bipolar Disorder and borderline personality disorder. Up to now, it is not possible to provide a definitive picture. In fact, there is currently significant debate about the relationship between Borderline Personality Disorder and Bipolar Disorder. MEDLINE searches were performed to identify the latest studies of these disorders, considering psychodynamic aspects. Bipolar disorder and borderline personality disorder share common clinical features, namely affective instability and impulsivity which however differ in quality. Consequently, to better understand these aspects, it is necessary to trace the stages of childhood psychological development. It has been claimed that Bipolar Disorder Type II can be divided into two subtypes: one stable and functional between episodes and one unstable between episodes which is related to Borderline Personality Disorder. However, better diagnostic theories, psychiatrist's empathy and patience remain the essential tool to understand and to face human suffering.

  1. International Society for Bipolar Disorders Task Force on Suicide

    DEFF Research Database (Denmark)

    Schaffer, Ayal; Isometsä, Erkki T; Tondo, Leonardo

    2015-01-01

    significantly associated with suicide attempts were: female gender, younger age at illness onset, depressive polarity of first illness episode, depressive polarity of current or most recent episode, comorbid anxiety disorder, any comorbid substance use disorder, alcohol use disorder, any illicit substance use......OBJECTIVES: Bipolar disorder is associated with a high risk of suicide attempts and suicide death. The main objective of the present study was to identify and quantify the demographic and clinical correlates of attempted and completed suicide in people with bipolar disorder. METHODS: Within...... the framework of the International Society for Bipolar Disorders Task Force on Suicide, a systematic review of articles published since 1980, characterized by the key terms bipolar disorder and 'suicide attempts' or 'suicide', was conducted, and data extracted for analysis from all eligible articles...

  2. Reviewing metallic PEMFC bipolar plates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Turner, J.A. [National Renewable Energy Laboratory, Golden, CO (United States)

    2010-08-15

    A bipolar plate is one of the most important components in a polymer exchange membrane fuel cell (PEMFC) stack and has multiple functions. Metallic bipolar plate candidates have advantages over composite rivals in excellent electrical and thermal conductivity, good mechanical strength, high chemical stability, very wide alloy choices, low cost and, most importantly, existing pathways for high-volume, high-speed mass production. The challenges with metallic bipolar plates are the higher contact resistance and possible corrosion products, which may contaminate the membrane electrode assembly. This review evaluates the candidate metallic and coating materials for bipolar plates and gives the perspective of the research trends. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  3. Cognitive and functional deficits in bipolar disorder and schizophrenia as a function of the presence and history of psychosis.

    Science.gov (United States)

    Bowie, Christopher R; Best, Michael W; Depp, Colin; Mausbach, Brent T; Patterson, Thomas L; Pulver, Ann E; Harvey, Philip D

    2018-05-18

    Schizophrenia and bipolar disorder overlap considerably. Schizophrenia is a primary psychotic disorder, whereas approximately half of people with bipolar disorder will experience psychosis. In this study, we examined the extent to which cognitive and functional impairments are related to the presence and history of psychosis across the two disorders. A total of 633 participants with bipolar disorder I, schizophrenia, and schizoaffective disorder were recruited for a study on the genetics of cognition and functioning in bipolar disorder and schizophrenia. Participants were classified into five groups: bipolar disorder with current psychosis (N = 30), bipolar disorder with a history of psychosis (N = 162), bipolar disorder with no history of psychosis (N = 92), schizophrenia with current psychosis (N = 245), and schizophrenia with past psychosis (N = 104). Cognitive profiles of all groups were similar in pattern; however, both current psychosis (P bipolar disorder and schizophrenia experienced similar impairments in real-world functioning if they were experiencing current psychosis (P = .32). The presence of active psychosis is an important cross-diagnostic factor in cognition and functioning in both schizophrenia and bipolar disorder. Characterization and treatment of cognition and functional deficits in bipolar disorder should consider the effects of both current and history of psychosis. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Bipolar zinc/oxygen battery development

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, S [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Schlatter, C [Swiss Federal Inst. of Technology, Lausanne (Switzerland)

    1997-06-01

    A bipolar electrically rechargeable Zn/O{sub 2} battery has been developed. Reticulated copper foam served as substrate for the zinc deposit on the anodic side, and La{sub 0.6}Ca{sub 0.4}CoO{sub 3}-catalyzed bifunctional oxygen electrodes were used on the cathodic side of the cells. The 100 cm{sup 2} unit cell had an open circuit voltage of 1,4 V(O{sub 2}) in moderately alkaline electrolyte. The open circuit voltage and the peak power measured for a stack containing seven cells were ca. 10V and 90W, respectively. The current-potential behaviour was determined as a function of the number of bipolar cells, and the maximum discharge capacity was determined at different discharge rates. (author) 4 figs., 1 ref.

  5. Scientific attitudes towards bipolar disorders

    Directory of Open Access Journals (Sweden)

    Mohammad-Hossein Biglu

    2014-02-01

    Full Text Available Introduction: Bipolar disorder is a psychiatric condition that is also called manic-depressive disease. It causes unusual changes in mood, energy, activity levels, and the ability to carry out day-to-day tasks. In the present study, 3 sets of data were considered and analyzed: first, all papers categorized under Bipolar Disorders in Science Citation Index Expanded (SCI-E database through 2001-2011; second, papers published by the international journal of Bipolar Disorders indexed in SCI-E during a period of 11 years; and third, all papers distributed by the international journal of Bipolar Disorders indexed in MEDLINE during the period of study. Methods: The SCI-E database was used to extract all papers indexed with the topic of Bipolar Disorders as well as all papers published by The International Journal of Bipolar Disorders. Extraction of data from MEDLINE was restricted to the journals name from setting menu. The Science of Science Tool was used to map the co-authorship network of papers published by The International Journal of Bipolar Disorders through 2009-2011. Results: Analysis of data showed that the majority of publications in the subject area of bipolar disorders indexed in SCI-E were published by The International Journal of Bipolar Disorders. Although journal articles consisted of 59% of the total publication type in SCI-E, 65% of publications distributed by The Journal of Bipolar Disorders were in the form of meetingabstracts. Journal articles consisted of only 23% of the total publications. USA was the leading country regarding sharing data in the field of bipolar disorders followed by England, Canada, and Germany. Conclusion: The editorial policy of The International Journal of Bipolar Disorders has been focused on new themes and new ways of researching in the subject area of bipolar disorder. Regarding the selection of papers for indexing, the SCI-E database selects data more comprehensively than MEDLINE. The number of papers

  6. Epidemiology in Pediatric Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Caner Mutlu

    2015-12-01

    Full Text Available Childhood and adolescent bipolar disorder diagnosis has been increasing recently. Since studies evaluating attempted suicide rates in children and adolescents have shown bipolarity to be a significant risk factor, diagnosis and treatment of bipolarity has become a very important issue. Since there is a lack of specific diagnostic criteria for especially preadolescent samples and evaluations are made mostly symptomatically, suspicions about false true diagnosis and increased prevalence rates have emerged. This situation leads to controversial data about the prevalence rates of bipolar disorder in children and adolescents. The aim of this article is to review the prevalence of childhood and adolescent bipolar disorder in community, inpatient and outpatient based samples in literature.

  7. Generation of metal composition gradients by means of bipolar electrodeposition

    International Nuclear Information System (INIS)

    Tisserant, Gwendoline; Fattah, Zahra; Ayela, Cédric; Roche, Jérome; Plano, Bernard; Zigah, Dodzi; Goudeau, Bertrand; Kuhn, Alexander; Bouffier, Laurent

    2015-01-01

    Highlights: • A bipolar electrochemistry approach for the preparation of surface gradients is reported. • Several metals are simultaneously deposited on a bipolar electrode. • The elemental composition and thickness of the deposit varies alongside the bipolar electrode. • The deposit affects the surface properties and exhibits a barcode feature. - Abstract: Bipolar electrochemistry is an unconventional technique that currently encounters a renewal of interest due to modern applications in the fields of analytical chemistry or materials science. The approach is particularly relevant for the preparation of asymmetric objects or surfaces such as Janus particles for example. Bipolar electrochemistry allows spatially controlled deposition of various layers from electroactive precursors, selectively at one side of a bipolar electrode. We report here the concomitant cathodic deposition of up to three different metals at the same time in a single experiment. The deposits were characterized by optical and electron microscopy imaging as well as profilometry and energy dispersive X-ray spectroscopy. As a result, the deposited layer is composed of several areas exhibiting both a composition and a thickness gradient. Such a variation directly modifies the optical and electronic properties alongside the surface and gives access to the design of composite surfaces exhibiting a visual gradient feature.

  8. Aberrant cerebellar connectivity in bipolar disorder with psychosis.

    Science.gov (United States)

    Shinn, Ann K; Roh, Youkyung S; Ravichandran, Caitlin T; Baker, Justin T; Öngür, Dost; Cohen, Bruce M

    2017-07-01

    The cerebellum, which modulates affect and cognition in addition to motor functions, may contribute substantially to the pathophysiology of mood and psychotic disorders, such as bipolar disorder. A growing literature points to cerebellar abnormalities in bipolar disorder. However, no studies have investigated the topographic representations of resting state cerebellar networks in bipolar disorder, specifically their functional connectivity to cerebral cortical networks. Using a well-defined cerebral cortical parcellation scheme as functional connectivity seeds, we compared ten cerebellar resting state networks in 49 patients with bipolar disorder and a lifetime history of psychotic features and 55 healthy control participants matched for age, sex, and image signal-to-noise ratio. Patients with psychotic bipolar disorder showed reduced cerebro-cerebellar functional connectivity in somatomotor A, ventral attention, salience, and frontoparietal control A and B networks relative to healthy control participants. These findings were not significantly correlated with current symptoms. Patients with psychotic bipolar disorder showed evidence of cerebro-cerebellar dysconnectivity in selective networks. These disease-related changes were substantial and not explained by medication exposure or substance use. Therefore, they may be mechanistically relevant to the underlying susceptibility to mood dysregulation and psychosis. Cerebellar mechanisms deserve further exploration in psychiatric conditions, and this study's findings may have value in guiding future studies on pathophysiology and treatment of mood and psychotic disorders, in particular.

  9. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    International Nuclear Information System (INIS)

    Pérez, Juan J.; Pérez-Cajaraville, Juan J.; Muñoz, Víctor; Berjano, Enrique

    2014-01-01

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m −1 ) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal

  10. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    Energy Technology Data Exchange (ETDEWEB)

    Pérez, Juan J. [Instituto de Investigación Interuniversitario en Bioingeniería y Tecnología Orientada al Ser Humano, Universitat Politècnica de València, Valencia 46022 (Spain); Pérez-Cajaraville, Juan J. [Pain Unit and Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, University of Navarra, Pamplona 31008 (Spain); Muñoz, Víctor [Neurotherm Spain, Barcelona 08303 (Spain); Berjano, Enrique, E-mail: eberjano@eln.upv.es [Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València 46022 (Spain)

    2014-07-15

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m{sup −1}) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of

  11. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief.

    Science.gov (United States)

    Pérez, Juan J; Pérez-Cajaraville, Juan J; Muñoz, Víctor; Berjano, Enrique

    2014-07-01

    Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a "strip lesion" to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m(-1)) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal damage zone dimension.

  12. Pituitary gland volumes in bipolar disorder.

    Science.gov (United States)

    Clark, Ian A; Mackay, Clare E; Goodwin, Guy M

    2014-12-01

    Bipolar disorder has been associated with increased Hypothalamic-Pituitary-Adrenal axis function. The mechanism is not well understood, but there may be associated increases in pituitary gland volume (PGV) and these small increases may be functionally significant. However, research investigating PGV in bipolar disorder reports mixed results. The aim of the current study was twofold. First, to assess PGV in two novel samples of patients with bipolar disorder and matched healthy controls. Second, to perform a meta-analysis comparing PGV across a larger sample of patients and matched controls. Sample 1 consisted of 23 established patients and 32 matched controls. Sample 2 consisted of 39 medication-naïve patients and 42 matched controls. PGV was measured on structural MRI scans. Seven further studies were identified comparing PGV between patients and matched controls (total n; 244 patients, 308 controls). Both novel samples showed a small (approximately 20mm(3) or 4%), but non-significant, increase in PGV in patients. Combining the two novel samples showed a significant association of age and PGV. Meta-analysis showed a trend towards a larger pituitary gland in patients (effect size: .23, CI: -.14, .59). While results suggest a possible small difference in pituitary gland volume between patients and matched controls, larger mega-analyses with sample sizes greater even than those used in the current meta-analysis are still required. There is a small but potentially functionally significant increase in PGV in patients with bipolar disorder compared to controls. Results demonstrate the difficulty of finding potentially important but small effects in functional brain disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Novel multiple criteria decision making methods based on bipolar neutrosophic sets and bipolar neutrosophic graphs

    OpenAIRE

    Muhammad, Akram; Musavarah, Sarwar

    2016-01-01

    In this research study, we introduce the concept of bipolar neutrosophic graphs. We present the dominating and independent sets of bipolar neutrosophic graphs. We describe novel multiple criteria decision making methods based on bipolar neutrosophic sets and bipolar neutrosophic graphs. We also develop an algorithm for computing domination in bipolar neutrosophic graphs.

  14. The Bipolar Interactive Psychoeducation (BIPED study: trial design and protocol

    Directory of Open Access Journals (Sweden)

    Jones Ian

    2009-08-01

    Full Text Available Abstract Background Bipolar disorders affect between 3–5% of the population and are associated with considerable lifelong impairment. Since much of the morbidity associated with bipolar disorder is caused by recurrent depressive symptoms, which are often only poorly responsive to antidepressants, there is a need to develop alternative, non-pharmacological interventions. Psychoeducational interventions have emerged as promising long-term therapeutic options for bipolar disorder. Methods/design The study is an exploratory, individually randomised controlled trial. The intervention known as 'Beating Bipolar' is a psychoeducational programme which is delivered via a novel web-based system. We will recruit 100 patients with a diagnosis of DSM-IV bipolar disorder (including type I and type II currently in clinical remission. The primary outcome is quality of life. This will be compared for those patients who have participated in the psychoeducational programme with those who received treatment as usual. Quality of life will be assessed immediately following the intervention as well as 10 months after randomisation. Secondary outcomes include current depressive and manic symptoms, number of episodes of depression and mania/hypomania experienced during the follow-up period, global functioning, functional impairment and insight. An assessment of costs and a process evaluation will also be conducted which will explore the feasibility and acceptability of the intervention as well as potential barriers to effectiveness. Discussion Bipolar disorder is common, under-recognised and often poorly managed. It is a chronic, life-long, relapsing condition which has an enormous impact on the individual and the economy. This trial will be the first to explore the effectiveness of a novel web-based psychoeducational intervention for patients with bipolar disorder which has potential to be easily rolled out to patients. Trial registration Current Controlled Trials

  15. Generic environmental statement on the routine use of plutonium-powered cardiac pacemakers

    International Nuclear Information System (INIS)

    Shoup, R.L.; Robinson, T.W.; O'Donnell, F.R.

    1976-01-01

    The purpose of a continuing program at ORNL is to provide technical assistance to the NRC on writing and editing of the final environmental statement on the routine use of nuclear-powered (primarily 238 Pu) cardiac pacemakers. This environmental statement defines the safety and reliability standards that nuclear-powered pacemakers are required to meet. All aspects of the risks to the patients, the public, and the environment are evaluated both for the routine use of plutonium-powered pacemakers and for postulated accidents involving pacemaker patients. Benefits derived from the use of plutonium-powered units are discussed and weighed against the risks in order to determine whether routine use is justified. Available alternative pacemakers with various performance characteristics are compared with respect to costs and to the needs of pacemaker patients

  16. Subjective consequences of permanent pacemaker therapy in patients under the age of retirement

    DEFF Research Database (Denmark)

    Mickley, H; Petersen, J; Nielsen, B L

    1989-01-01

    During a 5-year period, 81 patients ages 20 to 60 years old had implantation of a permanent cardiac pacemaker at the University Hospital, Odense. At follow-up, during 1985, the 73 survivors received a semi-structured questionnaire regarding subjective consequences of pacemaker therapy, and 72...... people (98.6%) agreed to participate. The mean pacing period (range) was 33.8 (11-72) months. Surgical intervention was required in 14 patients (19.4%) during follow-up. Regarding all symptoms 67 patients (93.1%) perceived benefit from the pacemaker. The effectiveness of cardiac pacing was most...... or a sensation of "impulses"/palpitations. To the majority (49 patients or 68.1%) pacemaker treatment did not influence quality of sexual activity. Six patients (8.3%) perceived an improvement, whereas a corresponding number felt deterioration in sexual activity following pacemaker implantation. Pacemaker...

  17. Semiconductor measurement technology: reliability technology for cardiac pacemakers 2: a workshop report, 1976

    International Nuclear Information System (INIS)

    Schafft, H.A.

    1977-01-01

    Summaries are presented of 12 invited talks on the following topics: the procurement and assurance of high reliability electronic parts, leak rate and moisture measurements, pacemaker batteries, and pacemaker leads. The workshop, second in a series, was held in response to strong interest expressed by the pacemaker community to address technical questions relevant to the enhancement and assurance of cardiac pacemaker reliability. Discussed at the workshop were a process validation wafer concept for assuring process uniformity in device chips; screen tests for assuring reliable electronic parts; reliability prediction; reliability comparison of semiconductor technologies; mechanisms of short-circuiting dendritic growths; details of helium and radioisotope leak test methods; a study to correlate package leak rates, as measured with test gasses, and actual moisture infusion; battery life prediction; microcalorimetric measurements to nondestructively evaluate batteries for pacemakers; and an engineer's and a physician's view of the present status of pacemaker leads. References are included with most of the reports

  18. Possible health hazards for cardiac pacemaker wearers from exposure to electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    1988-03-01

    Cardiac pacemakers are used to provide electrical stimulation to the heart when the heart's natural rhythm is interrupted. This study shows that they can be susceptible to electromagnetic fields. Pacemakers are well protected against common electromagnetic fields, such as those from household appliances. But intense electomagnetic fields, such as those found in some industrial settings, could affect the functioning of the pacemaker. Such interference may cause the pacemaker wearer to feel dizzy or experience an accelerated heartbeat. While this is not fatal, the pacemaker wearer should try to move away from the source of the interfering field and avoid situations in which interference could arise. After experiencing any of these symptoms, the pacemaker wearer should contact a physician. Potential sources of electromagnetic interference should be identified and characterized to determine if there could be an interference hazard. Exposure to interfering electomagnetic fields should be minimized. 7 refs., 1 fig.

  19. Conceptual design of GaN betavoltaic battery using in cardiac pacemaker

    International Nuclear Information System (INIS)

    Mohamadian, M.; Feghhi, S.A. H.; Afarideh, H.

    2007-01-01

    Introduction: Pacemaker is an electronic biomedical device which stimulates and regulates or amplify the human heartbeat by delivering weak electrical pulses to the cardiac muscle at regular intervals when its natural regulating mechanisms break down. Developments in design and implementation of power source in adjacent to advances in electronic circuitry is an important aspect in optimization of pacemakers. For instance, many implant patients continue to outlive their batteries and require costly and risky replacement surgery. So such device needs to have high energy density power source and maintain a stable current and voltage for a long period of time to avoid frequent replacements. In addition, the size is also an important consideration for implantable batteries. Betavoltaic batteries are being researched as a suitable source for these applications. Also, these batteries have vast application in which the replacement of batteries is highly inconvenient, such as in oil and mining industries, which often place sensors in dangerous or hard-to-reach locations. The purpose of the present investigation is determination of the optimal parameters of low energy GaN betavoltaic battery in artificial cardiac pacemakers using MCNP code which have higher efficiency than those available with previous devices, especially thermoelectric converters (∼15%). Material and Methods: In this design, two p-n diode structures from GaN semiconductor were used to collect the charge from a layer of 6 3Ni as a source which is centered between the two p-n junctions. MCNP simulation results have been used to determine the amount of electron current from interaction of beta particles in p-n junctions. Results and Discussion: Calculation results indicate that the short circuit current, open circuit voltage and efficiency of a single device are 1.1 μA/cm 2 , 2.7 volt and 25%, respectively. Also, it's concluded that with suitable arrangement of these single devices, one could construct a

  20. Parasitic bipolar amplification in a single event transient and its temperature dependence

    International Nuclear Information System (INIS)

    Liu Zheng; Chen Shu-Ming; Chen Jian-Jun; Qin Jun-Rui; Liu Rong-Rong

    2012-01-01

    Using three-dimensional technology computer-aided design (TCAD) simulation, parasitic bipolar amplification in a single event transient (SET) current of a single transistor and its temperature dependence are studied. We quantify the contributions of different current components in a SET current pulse, and it is found that the proportion of parasitic bipolar amplification in total collected charge is about 30% in both 130-nm and 90-nm technologies. The temperature dependence of parasitic bipolar amplification and the mechanism of the SET pulse are also investigated and quantified. The results show that the proportion of charge induced by parasitic bipolar increases with rising temperature, which illustrates that the parasitic bipolar amplification plays an important role in the charge collection of a single transistor

  1. The role of the salt electrolyt on the electrical conductive properties of a polymeric bipolar membrane

    NARCIS (Netherlands)

    Alcaraz, Antonio; Wilhelm, F.G.; Wessling, Matthias; Ramirez, Patricio

    2001-01-01

    We have studied the contribution of the salt electrolyte to the electrical conductive characteristics of a bipolar membrane. We present first a critical analysis of previous theoretical approaches, and discuss the limits of validity. Experimental current-voltage curves of several commercial bipolar

  2. Transdiagnostic Treatment of Bipolar Disorder and Comorbid Anxiety with the Unified Protocol: A Clinical Replication Series

    Science.gov (United States)

    Ellard, Kristen K.; Deckersbach, Thilo; Sylvia, Louisa G.; Nierenberg, Andrew A.; Barlow, David H.

    2012-01-01

    Bipolar disorder (BD) is a chronic, debilitating disorder with recurrent manic and depressive episodes. More than 75% of bipolar patients have a current or lifetime diagnosis of a comorbid anxiety disorder. Comorbid anxiety in BD is associated with greater illness severity, greater functional impairment, and poorer illness-related outcomes.…

  3. Add-on treatment with N-acetylcysteine for bipolar depression

    DEFF Research Database (Denmark)

    Ellegaard, Pernille Kempel; Licht, Rasmus Wentzer; Poulsen, Henrik Enghusen

    2018-01-01

    BACKGROUND: Oxidative stress and inflammation may be involved in the development and progression of mood disorders, including bipolar disorder. Currently, there is a scarcity of useful treatment options for bipolar depressive episodes, especially compared with the efficacy of treatment for acute ...

  4. Complex regional pain syndrome type I following pacemaker implantation

    Directory of Open Access Journals (Sweden)

    Sangita Kamath

    2015-12-01

    Full Text Available A 70-year-old woman presented with burning pain and swelling over dorsum of right hand and small joints of the fingers, associated with redness, feeling of warmth, and stiffness of the fingers, with inability to bend the fingers since 2 months. The symptoms were progressively increasing in intensity for the past 1 month. There was no history of fever or trauma to the hand. Two months before her symptoms started, she had permanent pacemaker implanted for complete heart block with syncope. She was hypertensive and was on regular medication. Her X-ray of right hand showed decreased bone density (demineralisation, suggestive of osteopenia. A diagnosis of reflex sympathetic dystrophy syndrome or complex regional pain syndrome type I induced by pacemaker insertion was made. She was treated with amitriptyline and steroids, after which her symptoms improved dramatically.

  5. Percutaneously Inject able Fetal Pacemaker: Electrodes, Mechanical Design and Implantation*

    Science.gov (United States)

    Zhou, Li; Chmait, Ramen; Bar-Cohen, Yaniv; Peck, Raymond A.; Loeb, Gerald E.

    2015-01-01

    We are developing a self-contained cardiac pacemaker with a small, cylindrical shape (~3×20mm) that permits it to be implanted percutaneously into a fetus to treat complete heart block and consequent hydrops fetalis, which is otherwise fatal. The device uses off-the-shelf components including a rechargeable lithium cell and a highly efficient relaxation oscillator encapsulated in epoxy and glass. A corkscrew electrode made from activated iridium can be screwed into the myocardium, followed by release of the pacemaker and a short, flexible lead entirely within the chest of the fetus to avoid dislodgement from fetal movement. The feasibility of implanting the device percutaneously under ultrasonic imaging guidance was demonstrated in acute adult rabbit experiments. PMID:23367442

  6. Percutaneously injectable fetal pacemaker: electrodes, mechanical design and implantation.

    Science.gov (United States)

    Zhou, Li; Chmait, Ramen; Bar-Cohen, Yaniv; Peck, Raymond A; Loeb, Gerald E

    2012-01-01

    We are developing a self-contained cardiac pacemaker with a small, cylindrical shape (~3 × 20 mm) that permits it to be implanted percutaneously into a fetus to treat complete heart block and consequent hydrops fetalis, which is otherwise fatal. The device uses off-the-shelf components including a rechargeable lithium cell and a highly efficient relaxation oscillator encapsulated in epoxy and glass. A corkscrew electrode made from activated iridium can be screwed into the myocardium, followed by release of the pacemaker and a short, flexible lead entirely within the chest of the fetus to avoid dislodgement from fetal movement. The feasibility of implanting the device percutaneously under ultrasonic imaging guidance was demonstrated in acute adult rabbit experiments.

  7. Dual chamber pacemaker implants - a new opportunity in Pakistan for children with congenital and acquired complete heart block

    International Nuclear Information System (INIS)

    Ashfaq, A.; Khan, M.A.; Atiq, M.

    2011-01-01

    Implantation of cardiac pacemakers has been practiced for at least five decades with continuous developments of the hardware. The invention of dual chamber pacemakers has initiated a debate concerning its superiority over single chamber ventricular pacemakers. Throughout the world, surgeons have been using dual chambered permanent pacemakers with successful follow ups. However, Pakistan has not yet taken the advantage of such pacemaker devices till now. We report three cases that underwent a dual chamber permanent pacemaker implantation for the first time in children less than 8 kg with successful follow ups. (author)

  8. Modulation of Pacemaker Potentials by Pyungwi-San in Interstitial Cells of Cajal from Murine Small Intestine - Pyungwi-San and Interstitial Cells of Cajal -

    Directory of Open Access Journals (Sweden)

    Kim Jung Nam

    2013-03-01

    Full Text Available Objective: Pyungwi-san (PWS plays a role in a number of physiologic and pharmacologic functions in many organs. Interstitial cells of Cajal (ICCs are pacemaker cells that generate slow waves in the gastrointestinal (GI tract. We aimed to investigate the beneficial effects of PWS in mouse small-intestinal ICCs. Methods: Enzymatic digestion was used to dissociate ICCs from the small intestine of a mouse. The wholecell patch-clamp configuration was used to record membrane potentials from the cultured ICCs. Results: ICCs generated pacemaker potentials in the GI tract. PWS produced membrane depolarization in the current clamp mode. Pretreatment with a Ca2+-free solution and a thapsigargin, a Ca2+-ATPase, inhibitor in the endoplasmic reticulum, eliminated the generation of pacemaker potentials. However, only when the thapsigargin was applied in a bath solution, the membrane depolarization was not produced by PWS. Furthermore, the membrane depolarizations due to PWS were inhibited not by U-73122, an active phospholipase C inhibitor, but by chelerythrine and calphostin C, protein kinase C inhibitors. Conclusions: These results suggest that PWS might affect GI motility by modulating the pacemaker activity in the ICCs.

  9. Tritium separation from light and heavy water by bipolar electrolysis

    International Nuclear Information System (INIS)

    Ramey, D.W.; Petek, M.; Taylor, R.D.; Kobisk, E.H.; Ramey, J.; Sampson, C.A.

    1979-10-01

    Use of bipolar electrolysis with countercurrent electrolyte flow to separate hydrogen isotopes was investigated for the removal of tritium from light water effluents or from heavy water moderator. Deuterium-tritium and protium-tritium separation factors occurring on a Pd-25% Ag bipolar electrode were measured to be 2.05 to 2.16 and 11.6 to 12.4 respectively, at current densities between 0.21 and 0.50 A cm -2 , and at 35 to 90 0 C. Current densities up to 0.3 A cm -2 have been achieved in continuous operation, at 80 to 90 0 C, without significant gas formation on the bipolar electrodes. From the measured overvoltage at the bipolar electrodes and the electrolyte conductivity the power consumption per stage was calculated to be 3.0 kwh/kg H 2 O at 0.2 A cm -2 and 5.0 kwh/kg H 2 O at 0.5 A cm -2 current density, compared to 6.4 and 8.0 kwh/kg H 2 O for normal electrolysis. A mathematical model derived for hydrogen isotope separation by bipolar electrolysis, i.e., for a square cascade, accurately describes the results for protium-tritium separation in two laboratory scale, multistage experiments with countercurrent electrolyte flow; the measured tiritum concentration gradient through the cascade agreed with the calculated values

  10. Bipolar pulse forming line

    Science.gov (United States)

    Rhodes, Mark A.

    2008-10-21

    A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  11. Leadless pacemaker extraction from a single-center perspective.

    Science.gov (United States)

    González Villegas, Elkin; Al Razzo, Omar; Silvestre García, Jorge; Mesa García, José

    2018-02-01

    Leadless pacemaker can be considered as a technical revolution in cardiac pacing devices, with clear advantages over conventional pacemakers in overcoming all lead-related complications. However, the management of these devices once they reach the end of life (EOL) of the battery is still controversial. In the next years, there will be an increase in the need to define a clear strategy in the management of leadless PM once they reach their EOL. Safe extraction of these devices will define in a great manner this strategy METHODS: We performed the extraction of three functioning Nanostim leadless pacemaker prophylactically in two females and one male patients as part of the Nanostim battery depletion field action recommendation. All patients had a prior transesophageal 3D echocardiography to determine the device intracardiac mobility and the extent of possible endothelialization. For the extractions, we used the Nanostim Retrieval Catheter S1RSIN (St. Jude Medical, St. Paul, MN, USA), which is a proprietary catheter provided by the manufacturing company based on a lasso. Complete extraction of the devices was achieved in all patients using a relatively short fluoroscopic time (16, 19, and 12 minutes). The extraction of leadless pacemakers can be considered as a safe and feasible procedure using the tools provided by the manufacturer and designed for the extraction. However, a very low threshold must be maintained to avoid any risk to the patients. Our extraction time ranges are between 983 and 1,070 days, nevertheless it is necessary to gather more long-term data to assess the feasibility and safety of these procedures. © 2017 Wiley Periodicals, Inc.

  12. Identification and functional characterization of cardiac pacemaker cells in zebrafish.

    Directory of Open Access Journals (Sweden)

    Federico Tessadori

    Full Text Available In the mammalian heart a conduction system of nodes and conducting cells generates and transduces the electrical signals evoking myocardial contractions. Specialized pacemaker cells initiating and controlling cardiac contraction rhythmicity are localized in an anatomically identifiable structure of myocardial origin, the sinus node. We previously showed that in mammalian embryos sinus node cells originate from cardiac progenitors expressing the transcription factors T-box transcription factor 3 (Tbx3 and Islet-1 (Isl1. Although cardiac development and function are strikingly conserved amongst animal classes, in lower vertebrates neither structural nor molecular distinguishable components of a conduction system have been identified, questioning its evolutionary origin. Here we show that zebrafish embryos lacking the LIM/homeodomain-containing transcription factor Isl1 display heart rate defects related to pacemaker dysfunction. Moreover, 3D reconstructions of gene expression patterns in the embryonic and adult zebrafish heart led us to uncover a previously unidentified, Isl1-positive and Tbx2b-positive region in the myocardium at the junction of the sinus venosus and atrium. Through their long interconnecting cellular protrusions the identified Isl1-positive cells form a ring-shaped structure. In vivo labeling of the Isl1-positive cells by transgenic technology allowed their isolation and electrophysiological characterization, revealing their unique pacemaker activity. In conclusion we demonstrate that Isl1-expressing cells, organized as a ring-shaped structure around the venous pole, hold the pacemaker function in the adult zebrafish heart. We have thereby identified an evolutionary conserved, structural and molecular distinguishable component of the cardiac conduction system in a lower vertebrate.

  13. Clinicohemodynamic and roentgenologic correlations in patients with artificial pacemakers

    International Nuclear Information System (INIS)

    Tatarchenko, I.P.; Iskenderov, B.G.; Koledinov, V.I.; Zhivotovskaya, G.G.

    1987-01-01

    The clinical pattern, central hemodynamics and roentgenologic data are studied in 34 patients with artificial cardiac pacemaker (ACP) to solve the problem on adequate medicamental therapy of heart failure (HF). Heart sizes and the state of a pulmonary image are estimated roentgenologically. Two types of cardiac-vessel system reactions on physical load: adequate and nonadequate - are detected. Implantation of ACP in patients with the nonadequate reaction does not lead to total liquidation of HF

  14. Clinicohemodynamic and roentgenologic correlations in patients with artificial pacemakers

    Energy Technology Data Exchange (ETDEWEB)

    Tatarchenko, I P; Iskenderov, B G; Koledinov, V I; Zhivotovskaya, G G

    1987-05-01

    The clinical pattern, central hemodynamics and roentgenologic data are studied in 34 patients with artificial cardiac pacemaker (ACP) to solve the problem on adequate medicamental therapy of heart failure (HF). Heart sizes and the state of a pulmonary image are estimated roentgenologically. Two types of cardiac-vessel system reactions on physical load: adequate and nonadequate - are detected. Implantation of ACP in patients with the nonadequate reaction does not lead to total liquidation of HF.

  15. Modeling the dual pacemaker system of the tau mutant hamster.

    Science.gov (United States)

    Oda, G A; Menaker, M; Friesen, W O

    2000-06-01

    Circadian pacemakers in many animals are compound. In rodents, a two-oscillator model of the pacemaker composed of an evening (E) and a morning (M) oscillator has been proposed based on the phenomenon of "splitting" and bimodal activity peaks. The authors describe computer simulations of the pacemaker in tau mutant hamsters viewed as a system of mutually coupled E and M oscillators. These mutant animals exhibit normal type 1 PRCs when released into DD but make a transition to a type 0 PRC when held for many weeks in DD. The two-oscillator model describes particularly well some recent behavioral experiments on these hamsters. The authors sought to determine the relationships between oscillator amplitude, period, PRC, and activity duration through computer simulations. Two complementary approaches proved useful for analyzing weakly coupled oscillator systems. The authors adopted a "distinct oscillators" view when considering the component E and M oscillators and a "system" view when considering the system as a whole. For strongly coupled systems, only the system view is appropriate. The simulations lead the authors to two primary conjectures: (1) the total amplitude of the pacemaker system in tau mutant hamsters is less than in the wild-type animals, and (2) the coupling between the unit E and M oscillators is weakened during continuous exposure of hamsters to DD. As coupling strength decreases, activity duration (alpha) increases due to a greater phase difference between E and M. At the same time, the total amplitude of the system decreases, causing an increase in observable PRC amplitudes. Reduced coupling also increases the relative autonomy of the unit oscillators. The relatively autonomous phase shifts of E and M oscillators can account for both immediate compression and expansion of activity bands in tau mutant and wild-type hamsters subjected to light pulses.

  16. A Systematic Review of Economic Evaluations of Pacemaker Telemonitoring Systems.

    Science.gov (United States)

    López-Villegas, Antonio; Catalán-Matamoros, Daniel; Martín-Saborido, Carlos; Villegas-Tripiana, Irene; Robles-Musso, Emilio

    2016-02-01

    Over the last decade, telemedicine applied to pacemaker monitoring has undergone extraordinary growth. It is not known if telemonitoring is more or less efficient than conventional monitoring. The aim of this study was to carry out a systematic review analyzing the available evidence on resource use and health outcomes in both follow-up modalities. We searched 11 databases and included studies published up until November 2014. The inclusion criteria were: a) experimental or observational design; b) studies based on complete economic evaluations; c) patients with pacemakers, and d) telemonitoring compared with conventional hospital monitoring. Seven studies met the inclusion criteria, providing information on 2852 patients, with a mean age of 81 years. The main indication for device implantation was atrioventricular block. With telemonitoring, cardiovascular events were detected and treated 2 months earlier than with conventional monitoring, thus reducing length of hospital stay by 34% and reducing routine and emergency hospital visits as well. There were no significant intergroup differences in perceived quality of life or number of adverse events. The cost of telemonitoring was 60% lower than that of conventional hospital monitoring. Compared with conventional monitoring, cardiovascular events were detected earlier and the number or hospitalizations and hospital visits was reduced with pacemaker telemonitoring. In addition, the costs associated with follow-up were lower with telemonitoring. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  17. Physiological effects of light on the human circadian pacemaker

    Science.gov (United States)

    Shanahan, T. L.; Czeisler, C. A.

    2000-01-01

    The physiology of the human circadian pacemaker and its influence and on the daily organization of sleep, endocrine and behavioral processes is an emerging interest in science and medicine. Understanding the development, organization and fundamental properties underlying the circadian timing system may provide insight for the application of circadian principles to the practice of clinical medicine, both diagnostically (interpretation of certain clinical tests are dependent on time of day) and therapeutically (certain pharmacological responses vary with the time of day). The light-dark cycle is the most powerful external influence acting upon the human circadian pacemaker. It has been shown that timed exposure to light can both synchronize and reset the phase of the circadian pacemaker in a predictable manner. The emergence of detectable circadian rhythmicity in the neonatal period is under investigation (as described elsewhere in this issue). Therefore, the pattern of light exposure provided in the neonatal intensive care setting has implications. One recent study identified differences in both amount of sleep time and weight gain in infants maintained in a neonatal intensive care environment that controlled the light-dark cycle. Unfortunately, neither circadian phase nor the time of day has been considered in most clinical investigations. Further studies with knowledge of principles characterizing the human circadian timing system, which governs a wide array of physiological processes, are required to integrate these findings with the practice of clinical medicine.

  18. Permanent and temporary pacemaker implantation after orthotopic heart transplantation

    Directory of Open Access Journals (Sweden)

    Bacal Fernando

    2000-01-01

    Full Text Available PURPOSE:To determine the indication for and incidence and evolution of temporary and permanent pacemaker implantation in cardiac transplant recipients. METHODS: A retrospective review of 114 patients who underwent orthotopic heart transplantation InCor (Heart Institute USP BR between March 1985 and May 1993. We studied the incidence of and indication for temporary pacing, the relationship between pacing and rejection, the need for pemanent pacing and the clinical follow-up. RESULTS: Fourteen of 114 (12%heart transplant recipients required temporary pacing and 4 of 114 (3.5% patients required permanent pacing. The indication for temporary pacing was sinus node dysfunction in 11 patients (78.5% and atrioventricular (AV block in 3 patients (21.4%. The indication for permanent pacemaker implantation was sinus node dysfunction in 3 patients (75% and atrioventricular (AV block in 1 patient (25%. We observed rejection in 3 patients (21.4% who required temporary pacing and in 2 patients (50% who required permanent pacing. The previous use of amiodarone was observed in 10 patients (71.4% with temporary pacing. Seven of the 14 patients (50% died during follow-up. CONCLUSION: Sinus node dysfunction was the principal indication for temporary and permanent pacemaker implantation in cardiac transplant recipients. The need for pacing was related to worse prognosis after cardiac transplantation.

  19. Pacemaker lead perforation of the right ventricle associated with Moraxella phenylpyruvica infection in a dog.

    Science.gov (United States)

    Ciavarella, A; Nimmo, J; Hambrook, L

    2016-04-01

    A 13-year-old neutered male Border Collie was presented with acute onset syncope, weakness and anorexia 10 months after transvenous pacemaker implantation. The patient was laterally recumbent, bradycardic (36 beats/min) and febrile (40.7°C) on presentation. An electrocardiogram (ECG) revealed recurrence of third-degree atrioventricular block with a ventricular escape rhythm. Fluoroscopy identified migration of the pacemaker tip through the apex of the right ventricle. Echocardiography failed to reveal any evidence of pericardial effusion or cardiac tamponade. Full postmortem was performed after euthanasia. The pacemaker lead had perforated the apex of the right ventricle and lodged in the right pleural space. Culture of blood (taken antemortem), pericardial sac, right ventricular wall (surrounding pacemaker lead), pacemaker lead tip and pericardial fluid revealed a pure growth of Moraxella phenylpyruvica. Bacteraemia associated with M. phenylpyruvica has never been reported in the dog, but sporadic cases are reported in humans. Infection could have resulted from either pre-existing myocarditis or opportunistic infection and bacteraemia post pacemaker implantation. Evaluation of the pacemaker function at regular intervals would allow early detection of poor pacemaker-to-myocardium contact, which would prompt further investigation of pacemaker lead abnormalities such as perforation. © 2016 Australian Veterinary Association.

  20. Continued evaluation of cardiac pacemakers. Annual report Jun 73-31 Aug 75

    International Nuclear Information System (INIS)

    Brueschke, E.E.; Uretz, E.F.; Hauser, R.G.

    1976-01-01

    The nuclear powered pacemaker evaluation was designed to characterize the operating characteristics of such pacemakers and identify potential failure mechanisms. More than 30 nuclear powered pacemakers were implanted in dogs and 15 were subjected to high stress bench tests. This evaluation resulted in the identification of several basic pacemaker problem areas for the batteries under test. These included abrupt and gradual nuclear battery failures, weld seam defects (in one model) resulting in pulse generator failures, pulse generator lead connector defects and pulse generator electronic malfunctions

  1. Swim pacemakers in box jellyfish are modulated by the visual input

    DEFF Research Database (Denmark)

    Garm, Anders Lydik; Bielecki, Jan

    2008-01-01

    A major part of the cubozoan central nervous system is situated in the eye-bearing rhopalia. One of the neuronal output channels from the rhopalia carries a swim pacemaker signal, which has a one-to-one relation with the swim contractions of the bell shaped body. Given the advanced visual system...... of box jellyfish and that the pacemaker signal originates in the vicinity of these eyes, it seems logical to assume that the pacemakers are modified by the visual input. Here, the firing frequency and distribution of inter-signal intervals (ISIs) of single pacemakers are examined in the Caribbean box...

  2. Permanent Pacemaker Lead Induced Severe Tricuspid Regurgitation in Patient Undergoing Multiple Valve Surgery

    Directory of Open Access Journals (Sweden)

    Jung Hee Lee

    2015-04-01

    Full Text Available Severe and permanent tricuspid regurgitation induced by pacemaker leads is rarely reported in the literature. The mechanism of pacemaker-induced tricuspid regurgitation has been identified, but its management has not been well established. Furthermore, debate still exists regarding the proper surgical approach. We present the case of a patient with severe tricuspid regurgitation induced by a pacemaker lead, accompanied by triple valve disease. The patient underwent double valve replacement and tricuspid valve repair without removal of the pre-existing pacemaker lead. The operation was successful and the surgical procedure is discussed in detail.

  3. Permanent pacemaker lead induced severe tricuspid regurgitation in patient undergoing multiple valve surgery.

    Science.gov (United States)

    Lee, Jung Hee; Kim, Tae Ho; Kim, Wook Sung

    2015-04-01

    Severe and permanent tricuspid regurgitation induced by pacemaker leads is rarely reported in the literature. The mechanism of pacemaker-induced tricuspid regurgitation has been identified, but its management has not been well established. Furthermore, debate still exists regarding the proper surgical approach. We present the case of a patient with severe tricuspid regurgitation induced by a pacemaker lead, accompanied by triple valve disease. The patient underwent double valve replacement and tricuspid valve repair without removal of the pre-existing pacemaker lead. The operation was successful and the surgical procedure is discussed in detail.

  4. Radiation therapy planning of a breast cancer patient with in situ pacemaker-challenges and lessons

    Energy Technology Data Exchange (ETDEWEB)

    Munshi, Anusheel; Wadasadawala, Tabassum; Budrukkar, Ashwini; Jalali, Rakesh; Dinshaw, Ketayun A [Dept. of Radiation Oncology, Tata Memorial Hospital, Mumbai (India); Sharma, Pramod Kumar; Sharma, Dayananda [Dept. of Radiation Physics, Tata Memorial Hospital, Mumbai (India)

    2008-02-15

    A postmenopausal lady with an in situ pacemaker developed a lump in the left breast and was diagnosed to have breast cancer. The patient underwent breast conservative surgery and was planned for post operative radiotherapy. The location of the tumor relative to the pacemaker provided a unique challenge in planning radiotherapy and the patient had an uneventful post radiotherapy course. A literature review revealed that modern generation pacemakers are very sensitive to radiation compared to their older counterparts. The present article makes suggestions towards reducing dose in radiotherapy planning in pacemaker patients

  5. Radiation therapy planning of a breast cancer patient with in situ pacemaker-challenges and lessons

    International Nuclear Information System (INIS)

    Munshi, Anusheel; Wadasadawala, Tabassum; Budrukkar, Ashwini; Jalali, Rakesh; Dinshaw, Ketayun A.; Sharma, Pramod Kumar; Sharma, Dayananda

    2008-01-01

    A postmenopausal lady with an in situ pacemaker developed a lump in the left breast and was diagnosed to have breast cancer. The patient underwent breast conservative surgery and was planned for post operative radiotherapy. The location of the tumor relative to the pacemaker provided a unique challenge in planning radiotherapy and the patient had an uneventful post radiotherapy course. A literature review revealed that modern generation pacemakers are very sensitive to radiation compared to their older counterparts. The present article makes suggestions towards reducing dose in radiotherapy planning in pacemaker patients

  6. Asenapine for bipolar disorder

    Directory of Open Access Journals (Sweden)

    Scheidemantel T

    2015-12-01

    Full Text Available Thomas Scheidemantel,1 Irina Korobkova,2 Soham Rej,3,4 Martha Sajatovic1,2 1University Hospitals Case Medical Center, 2Case Western Reserve University School of Medicine, Cleveland, OH, USA; 3Department of Psychiatry, University of Toronto, Toronto, ON, 4Geri PARTy Research Group, Jewish General Hospital, Montreal, QC, Canada Abstract: Asenapine (Saphris® is an atypical antipsychotic drug which has been approved by the US Food and Drug Administration for the treatment of schizophrenia in adults, as well as the treatment of acute manic or mixed episodes of bipolar I in both adult and pediatric populations. Asenapine is a tetracyclic drug with antidopaminergic and antiserotonergic activity with a unique sublingual route of administration. In this review, we examine and summarize the available literature on the safety, efficacy, and tolerability of asenapine in the treatment of bipolar disorder (BD. Data from randomized, double-blind trials comparing asenapine to placebo or olanzapine in the treatment of acute manic or mixed episodes showed asenapine to be an effective monotherapy treatment in clinical settings; asenapine outperformed placebo and showed noninferior performance to olanzapine based on improvement in the Young Mania Rating Scale scores. There are limited data available on the use of asenapine in the treatment of depressive symptoms of BD, or in the maintenance phase of BD. The available data are inconclusive, suggesting the need for more robust data from prospective trials in these clinical domains. The most commonly reported adverse effect associated with use of asenapine is somnolence. However, the somnolence associated with asenapine use did not cause significant rates of discontinuation. While asenapine was associated with weight gain when compared to placebo, it appeared to be modest when compared to other atypical antipsychotics, and its propensity to cause increases in hemoglobin A1c or serum lipid levels appeared to be

  7. Hypersexuality and couple relationships in bipolar disorder: A review.

    Science.gov (United States)

    Kopeykina, Irina; Kim, Hae-Joon; Khatun, Tasnia; Boland, Jennifer; Haeri, Sophia; Cohen, Lisa J; Galynker, Igor I

    2016-05-01

    with comorbid substance use as well as inpatient, outpatient, symptomatic and euthymic patients, may limit the generalizability of results. Although bipolar patients experience disease-specific sexual problems of mania-induced hypersexuality and specific effects of mood cycling on couple relationships, the existing literature is mostly outdated and lacks a consistent definition of hypersexuality. Novel research is needed to address sexual symptomatology in bipolar disorder within the context of current sexual, cultural and gender norms. Copyright © 2016. Published by Elsevier B.V.

  8. Connectivity of Pacemaker Neurons in the Neonatal Rat Superficial Dorsal Horn

    Science.gov (United States)

    Ford, Neil C.; Arbabi, Shahriar; Baccei, Mark L.

    2014-01-01

    Pacemaker neurons with an intrinsic ability to generate rhythmic burst-firing have been characterized in lamina I of the neonatal spinal cord, where they are innervated by high-threshold sensory afferents. However, little is known about the output of these pacemakers, as the neuronal populations which are targeted by pacemaker axons have yet to be identified. The present study combines patch clamp recordings in the intact neonatal rat spinal cord with tract-tracing to demonstrate that lamina I pacemaker neurons contact multiple spinal motor pathways during early life. Retrograde labeling of premotor interneurons with the trans-synaptic virus PRV-152 revealed the presence of burst-firing in PRV-infected lamina I neurons, thereby confirming that pacemakers are synaptically coupled to motor networks in the spinal ventral horn. Notably, two classes of pacemakers could be distinguished in lamina I based on cell size and the pattern of their axonal projections. While small pacemaker neurons possessed ramified axons which contacted ipsilateral motor circuits, large pacemaker neurons had unbranched axons which crossed the midline and ascended rostrally in the contralateral white matter. Recordings from identified spino-parabrachial and spino-PAG neurons indicated the presence of pacemaker activity within neonatal lamina I projection neurons. Overall, these results show that lamina I pacemakers are positioned to regulate both the level of activity in developing motor circuits as well as the ascending flow of nociceptive information to the brain, thus highlighting a potential role for pacemaker activity in the maturation of pain and sensorimotor networks in the CNS. PMID:25380417

  9. Tilt-table testing of patients with pacemaker and recurrent syncope

    DEFF Research Database (Denmark)

    Nielsen, Christian E. Haarmark; Kanters, Jørgen K; Mehlsen, Jesper

    2016-01-01

    responses accounting for 72% of patients with a positive test. There were no differences between groups with positive or negative test result regarding age, gender, resting blood pressure and heart rate, daily fluid intake, pacing mode, pacing indication or pacing rhythm at rest. HUT in patients...... protocol with nitroglycerine provocation was used and the test results were classified according to current guidelines. Baseline data were retrieved from the medical records. Overall, 54% of patients had a positive response to HUT. Vasodepressor or orthostatic hypotensive response were the most prevalent...... with pacemakers has a high diagnostic yield. Although, the majority of patients had a vasodepressor or orthostatic hypotensive response, cardioinhibitory response leading to syncope was also seen....

  10. Bipolar explosion models for hypernovae

    International Nuclear Information System (INIS)

    Maeda, Keiichi; Nomoto, Ken'ichi

    2003-01-01

    Bipolar explosion models for hypernovae (very energetic supernovae) are presented. These models provide a favorable situation to explain some unexpected features in observations of hypernovae, e.g., high velocity matter dominated by Fe and low velocity matter dominated by O. The overall abundance of these models gives a good fit, at least qualitatively, to abundances in extremely metal-poor stars. We suggest hypernovae be driven by bipolar jets and contribute significantly to the early Galactic chemical evolution

  11. Functional remediation for bipolar disorder

    OpenAIRE

    Martínez-Arán, Anabel, 1971-; Torrent, C.; Solé, B.; Bonnín, C.M.; Rosa, A.R.; Sánchez-Moreno, J.; Vieta i Pascual, Eduard, 1963-

    2014-01-01

    Neurocognitive impairment constitutes a core feature of bipolar illness. The main domains affected are verbal memory, attention, and executive functions. Deficits in these areas as well as difficulties to get functional remission seem to be increased associated with illness progression. Several studies have found a strong relationship between neurocognitive impairment and low functioning in bipolar disorder, as previously reported in other illnesses such as schizophrenia. Cognitive remediatio...

  12. [Psychoeducation and interpersonal and social rhythm therapy for bipolar disorder].

    Science.gov (United States)

    Mizushima, Hiroko

    2011-01-01

    In treating bipolar disorder, specific psychotherapies in adjunct to pharmacotherapy have been shown to be effective in preventing new episodes and treating depressive episodes. Among those, interpersonal and social rhythm therapy (IPSRT) developed by Frank, amalgamation of interpersonal psychotherapy (IPT) with behavioral therapy focused on social rhythm has been shown to be an efficacious adjunct to mediation in preventing new episodes in bipolar I patients and in treating depression in bipolar I arid II disorder. IPSRT has also been shown to enhance total functioning, relationship functioning and life satisfaction among patients with bipolar disorder, even after pretreatment functioning and concurrent depression were covaried. IPSRT was designed to directly address the major pathways to recurrence in bipolar disorder, namely medication nonadherence, stressful life events, and disruptions in social rhythms. IPT, originated by Klerman et al., is a strategic time-limited psychotherapy focused on one or two of four current interpersonal problem areas (ie, grief, interpersonal role disputes, role transitions, and interpersonal dificits). In IPSRT, the fifth problem area "grief for the lost healthy self" has been added in order to promote acceptance of the diagnosis and the need for life-long treatment. Social rhythm therapy is a behavioral approach aiming at increasing regularity of social rhythms using the Social Rhythm Metric (SRM), a chart to record daily social activities including how stimulating they were, developed from observation that disruptions in social rhythms often trigger affective episodes in patients with bipolar disorder. IPSRT also appears to be a promising intervention for a subset of individuals with bipolar II depression as monotherapy for the acute treatment.

  13. Zebrafish heart as a model to study the integrative autonomic control of pacemaker function

    Science.gov (United States)

    Stoyek, Matthew R.; Quinn, T. Alexander; Croll, Roger P.

    2016-01-01

    The cardiac pacemaker sets the heart's primary rate, with pacemaker discharge controlled by the autonomic nervous system through intracardiac ganglia. A fundamental issue in understanding the relationship between neural activity and cardiac chronotropy is the identification of neuronal populations that control pacemaker cells. To date, most studies of neurocardiac control have been done in mammalian species, where neurons are embedded in and distributed throughout the heart, so they are largely inaccessible for whole-organ, integrative studies. Here, we establish the isolated, innervated zebrafish heart as a novel alternative model for studies of autonomic control of heart rate. Stimulation of individual cardiac vagosympathetic nerve trunks evoked bradycardia (parasympathetic activation) and tachycardia (sympathetic activation). Simultaneous stimulation of both vagosympathetic nerve trunks evoked a summative effect. Effects of nerve stimulation were mimicked by direct application of cholinergic and adrenergic agents. Optical mapping of electrical activity confirmed the sinoatrial region as the site of origin of normal pacemaker activity and identified a secondary pacemaker in the atrioventricular region. Strong vagosympathetic nerve stimulation resulted in a shift in the origin of initial excitation from the sinoatrial pacemaker to the atrioventricular pacemaker. Putative pacemaker cells in the sinoatrial and atrioventricular regions expressed adrenergic β2 and cholinergic muscarinic type 2 receptors. Collectively, we have demonstrated that the zebrafish heart contains the accepted hallmarks of vertebrate cardiac control, establishing this preparation as a viable model for studies of integrative physiological control of cardiac function by intracardiac neurons. PMID:27342878

  14. I-123 metaiodobenzylguanidine cardiac scintigraphy in patients with an implanted permanent pacemaker

    International Nuclear Information System (INIS)

    Nakata, Akio; Hirota, Satoshi; Tsuji, Hiroshi; Takazakura, Eisuke

    1995-01-01

    Tl scintigraphic abnormalities have been reported in patients with an implanted permanent pacemaker, but little is known about the MIBG scintigraphic findings in such patients. This study was performed to assess the MIBG scintigraphic findings in patients with an implanted permanent pacemaker, and to test the hypothesis that imaging characteristics of MIBG scintigraphy differ according to its mode. Twelve patients (4 men and 8 women, mean age: 72.4±9.5 years), who had undergone the implantation of a permanent pacemaker for bradyarrhythmias, underwent MIBG scintigraphy. The patients were divided into VVI pacemaker and DDD pacemaker groups. The tomograms were divided into nine segments and the MIBG defect in each segment scored on a scale ranging from 0 (normal uptake) to 3 (no uptake). Total MIBG defect scores were generated by summing the scores for the nine segments in each patient. MIBG scintigraphic abnormalities were found in ten of the twelve patients. The six patients with the VVI pacemaker manifested MIBG scintigraphic abnormalities. These MIBG scintigraphic abnormalities were observed in all segments, particularly in the posterior segments. The mean total defect score of the VVI group was higher than that of the DDD group (14.8±9.8 vs 3.0±3.5, respectively p<0.05). Therefore, we conclude that despite several limitations of the study, MIBG scintigraphic abnormalities occur in patients with implanted permanent pacemakers, and that such abnormalities are more prominent with the VVI than DDD pacemaker. (author)

  15. Low pacemaker incidence with continuous-sutured valves: a retrospective analysis.

    Science.gov (United States)

    Niclauss, Lars; Delay, Dominique; Pfister, Raymond; Colombier, Sebastien; Kirsch, Matthias; Prêtre, René

    2017-06-01

    Background Permanent pacemaker implantation after surgical aortic valve replacement depends on patient selection and risk factors for conduction disorders. We aimed to identify risk criteria and obtain a selected group comparable to patients assigned to transcatheter aortic valve implantation. Methods Isolated sutured aortic valve replacements in 994 patients treated from 2007 to 2015 were reviewed. Demographics, hospital stay, preexisting conduction disorders, surgical technique, and etiology in patients with and without permanent pacemaker implantation were compared. Reported outcomes after transcatheter aortic valve implantation were compared with those of a subgroup including only degenerative valve disease and first redo. Results The incidence of permanent pacemaker implantation was 2.9%. Longer hospital stay ( p = 0.01), preexisting rhythm disorders ( p pacemaker implantation. Although prostheses were sutured with continuous monofilament in the majority of cases (86%), interrupted pledgetted sutures were used more often in the pacemaker group ( p = 0.002). In the subgroup analysis, the incidence of permanent pacemaker implantation was 2%; preexisting rhythm disorders and the suture technique were still major risk factors. Conclusion Permanent pacemaker implantation depends on etiology, preexisting rhythm disorders, and suture technique, and the 2% incidence compares favorably with the reported 5- to 10-fold higher incidence after transcatheter aortic valve implantation. Cost analysis should take this into account. Often dismissed as minor complication, permanent pacemaker implantation increases the risks of endocarditis, impaired myocardial recovery, and higher mortality if associated with prosthesis regurgitation.

  16. PreBötzinger complex and pacemaker neurons: hypothesized site and kernel for respiratory rhythm generation

    DEFF Research Database (Denmark)

    Rekling, J C; Feldman, J L

    1998-01-01

    Identification of the sites and mechanisms underlying the generation of respiratory rhythm is of longstanding interest to physiologists and neurobiologists. Recently, with the development of novel experimental preparations, especially in vitro en bloc and slice preparations of rodent brainstem, p...... activity of pacemaker or group-pacemaker neurons....

  17. Does high-power computed tomography scanning equipment affect the operation of pacemakers?

    International Nuclear Information System (INIS)

    Yamaji, Satoshi; Imai, Shinobu; Saito, Fumio; Yagi, Hiroshi; Kushiro, Toshio; Uchiyama, Takahisa

    2006-01-01

    Computed tomography (CT) is widely used in clinical practice, but there has not been a detailed report of its effect on the functioning of pacemakers. During CT, ECGs were recorded in 11 patients with pacemakers and the electromagnetic field in the CT room was also measured. The effect of CT on a pacemaker was also investigated in a human body model with and without shielding by rubber or lead. Transient malfunctions of pacemakers during CT occurred in 6 of 11 patients. The model showed that malfunctioning of the pacemaker was induced by CT scanning and this was prevented by lead but not by rubber. The alternating electrical field was 150 V/m on the CT scanning line, which was lower than the level influencing pacemaker functions. The alternating magnetic field was 15μT on the CT scanning line, which was also lower than the level influencing pacemaker functions. Malfunctions of the pacemaker during CT may be caused by diagnostic radiant rays and although they are transient, the possibility of lethal arrhythmia cannot be ignored. (author)

  18. Interference of apex locator, pulp tester and diathermy on pacemaker function.

    Science.gov (United States)

    Sriman, Narayanan; Prabhakar, V; Bhuvaneswaran, J S; Subha, N

    2015-01-01

    The purpose of this study was to evaluate the effects of three electronic apex locators (EAL), electric pulp tester (EPT) and diathermy on pacemaker function in vitro. Three EALs: Root ZX (J. Morita Co., Tustin, CA, U.S.A.), Propex (Dentsply), Mini Apex locator (SybronEndo, Anaheim, CA, USA), EPT (Parkell pulp vitality tester Farmingdale, NY, USA) and Diathermy (Neomed 250 B) were tested for any interference with one pacemaker (A medtronic kappa KVDD901-serial number: PLE734632S). Directly connecting the pacemaker lead with the EAL/EPT/diathermy operating on a flat bench top, the telemetry wand was held directly over the pacemaker to monitor the pacing pattern for a period of 30 s. Pacemaker activity was continuously recorded on the telemetric programmer and electro gram (EGM) readings examined for pacer inhibition, noise reversion or inappropriate pacemaker pulses. All the three apex locators showed no pacing interference or background noise during its function or at rest. The EGM readings of EPT showed varying levels of background noise in between pacing however, this did not affect the normal pacing pattern and the pacing interval remained constant. EGM readings of diathermy showed an increase in the pacing interval (irregular pacing pattern) followed by complete inhibition of the pacing system. The tested EALs do not interfere with cardiac pacemaker function. The tested EPT showed varying levels of background noise but does not interfere with cardiac pacemaker function. Use of Diathermy interfered with the normal pacing, leading to complete inhibition of the pacing system.

  19. Pacemaker and radiotherapy in breast cancer: is targeted intraoperative radiotherapy the answer in this setting?

    International Nuclear Information System (INIS)

    Keshtgar, Mohammed RS; Eaton, David J; Reynolds, Claire; Pigott, Katharine; Davidson, Tim; Gauter-Fleckenstein, Benjamin; Wenz, Frederik

    2012-01-01

    We present the case of an 83 year old woman with a cardiac pacemaker located close in distance to a subsequently diagnosed invasive ductal carcinoma of the left breast. Short range intraoperative radiotherapy was given following wide local excision and sentinel node biopsy. The challenges of using ionising radiation with pacemakers is also discussed

  20. Subacute Right Ventricle Perforation by Pacemaker Lead Presenting with Left Hemothorax and Shock

    Directory of Open Access Journals (Sweden)

    Julianne Nichols

    2015-01-01

    Full Text Available Cardiac perforation by pacemaker is a rare but potentially fatal complication. Acute perforations occurring within twenty-four hours of insertion of pacemaker can lead to hemopericardium, cardiac tamponade, and death. Hemothorax occurring as an acute complication of pacemaker insertion is reported but extremely rare. Previously, hemothorax and shock as a subacute complication following pacemaker insertion have not been reported. We report the case of an 85-year-old patient who presented with shock from hemothorax caused by pacemaker perforation, two weeks after insertion. Device interrogation showed normal function. Chest X-ray and echocardiogram missed lead dislocation and the diagnosis was made on computed tomogram (CT of the chest. Following surgical repair, a new ventricular pacemaker was placed transvenously in the right ventricular septum. This case illustrates that CT scan of the chest should be performed in all patients in whom cardiac perforation by pacemaker is suspected but not diagnosed on chest X-ray and echocardiogram. Normal functioning of pacemaker on device interrogation does not exclude perforation.

  1. Subacute right ventricle perforation by pacemaker lead presenting with left hemothorax and shock.

    Science.gov (United States)

    Nichols, Julianne; Berger, Natalie; Joseph, Praveen; Datta, Debapriya

    2015-01-01

    Cardiac perforation by pacemaker is a rare but potentially fatal complication. Acute perforations occurring within twenty-four hours of insertion of pacemaker can lead to hemopericardium, cardiac tamponade, and death. Hemothorax occurring as an acute complication of pacemaker insertion is reported but extremely rare. Previously, hemothorax and shock as a subacute complication following pacemaker insertion have not been reported. We report the case of an 85-year-old patient who presented with shock from hemothorax caused by pacemaker perforation, two weeks after insertion. Device interrogation showed normal function. Chest X-ray and echocardiogram missed lead dislocation and the diagnosis was made on computed tomogram (CT) of the chest. Following surgical repair, a new ventricular pacemaker was placed transvenously in the right ventricular septum. This case illustrates that CT scan of the chest should be performed in all patients in whom cardiac perforation by pacemaker is suspected but not diagnosed on chest X-ray and echocardiogram. Normal functioning of pacemaker on device interrogation does not exclude perforation.

  2. A forced desynchrony study of circadian pacemaker characteristics in seasonal affective disorder

    NARCIS (Netherlands)

    Koorengevel, Kathelijne M.; Beersma, Domien G.M.; den Boer, Johan; Hoofdakker, Rutger H. van den

    2002-01-01

    The circadian pacemaker is an endogenous clock that regulates oscillations in most physiological and psychological processes with a near 24-h period. In many species, this pacemaker triggers seasonal changes in behavior. The seasonality of symptoms and the efficacy of light therapy suggest

  3. Circadian Activators Are Expressed Days before They Initiate Clock Function in Late Pacemaker Neurons from Drosophila.

    Science.gov (United States)

    Liu, Tianxin; Mahesh, Guruswamy; Houl, Jerry H; Hardin, Paul E

    2015-06-03

    Circadian pacemaker neurons in the Drosophila brain control daily rhythms in locomotor activity. These pacemaker neurons can be subdivided into early or late groups depending on whether rhythms in period (per) and timeless (tim) expression are initiated at the first instar (L1) larval stage or during metamorphosis, respectively. Because CLOCK-CYCLE (CLK-CYC) heterodimers initiate circadian oscillator function by activating per and tim transcription, a Clk-GFP transgene was used to mark when late pacemaker neurons begin to develop. We were surprised to see that CLK-GFP was already expressed in four of five clusters of late pacemaker neurons during the third instar (L3) larval stage. CLK-GFP is only detected in postmitotic neurons from L3 larvae, suggesting that these four late pacemaker neuron clusters are formed before the L3 larval stage. A GFP-cyc transgene was used to show that CYC, like CLK, is also expressed exclusively in pacemaker neurons from L3 larval brains, demonstrating that CLK-CYC is not sufficient to activate per and tim in late pacemaker neurons at the L3 larval stage. These results suggest that most late pacemaker neurons develop days before novel factors activate circadian oscillator function during metamorphosis. Copyright © 2015 the authors 0270-6474/15/358662-10$15.00/0.

  4. A proposal for a standard communication protocol for pacemaker/ICD programmers

    NARCIS (Netherlands)

    Dijk, WA; Hooijschuur, CAM; van der Velde, W; Dassen, WRM

    2005-01-01

    The information generated by pacemakers and ICD's to support the cardiologist and technician for installing the optimal settings for the patient is increasing rapidly. In this paper a proposal is described for electronic data exchange between the pacemaker/ICD programmers and electronic information

  5. Twiddler-syndrom er en årsag til pacemaker elektrode displacering

    DEFF Research Database (Denmark)

    Grønbech, Keea Treu; Hansen, Michael Gilså

    2013-01-01

    Twiddler's syndrome is a rare cause of pacemaker electrode displacement. The displacement is caused by the patient's manipulation with the pacemaker, so the electrode is retracted. We describe a case of a 79-year-old overweight woman with a known psychiatric anamnesis, who was admitted twice...

  6. Basic Principles of Interpersonal Social Rhythm Therapy in Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Gokben Hizli Sayar

    2014-08-01

    Full Text Available Interpersonal Social Rhythm Therapy is a psychotherapy modality that helps the patient recognize the relationship between disruptions in social rhythms and the onset of previous episodes of psychiatric disorders. It uses psychoeducation and behavioral techniques to maintain social rhythm and sleep/wake regularity. It is closely related to and ldquo;social zeitgeber theory and rdquo; that emphasizes the importance that social rhythm regularity may play in synchronization of circadian rhythms in individuals with or at risk for bipolar spectrum disorders. Interpersonal and social rhythm therapy have been shown to stabilize social rhythms and enhance course and outcome in bipolar disorder. This review focuses on the theoretical principles and the basic steps of interpersonal and social rhythm therapy as a psychotherapy approach in bipolar disorder. PubMed, Scopus, Google Scholar databases were searched without temporal restriction. Search terms included interpersonal social rhythm therapy, bipolar, mood disorders. Abstracts were reviewed for relevance, and randomized controlled trials of interpersonal and social rhythm therapy in bipolar disorder selected. These researches also summarized on the final part of this review. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 438-446

  7. Cognitive functions in the euthymic patients with bipolar disorder

    International Nuclear Information System (INIS)

    Ozdel, O.; Karadag, F.; Atesci, Figen C.; Oguzhanoglu, N.K.; Cabuk, T.

    2007-01-01

    Recent studies have focused on the nature of dysfunction in bipolar patients. The purpose of the current study was to investigate cognitive performance of individuals with bipolar disorder compared to healthy control subjects during a well-established euthymic period. The sample consisted of 27 bipolar euthymic patients and 21 control subjects. Verbal and visual memory performance, attention, executive functions and psychological functions were evaluated for each participant. Bipolar patients showed significant attentional deficit and executive dysfunction and also poor performance on verbal and visual memory tasks compared to the controls. Illness duration and lifetime total episode number and previous episode with psychotic features was associated with worsened performance on attention, executive and memory tasks. Psychological functioning was not associated with cognitive deficit. The present study showed persistent cognitive impairment on inhibitory control and selective attention as well as poor performance on verbal and visual memory tests in a group of bipolar euthymic patients. The impaired neuropsychological performance was associated with psychotic features. Attentional dysfunction seemed to be a trait abnormality for the sample studied. (author)

  8. The influence of electromagnetic interference and ionizing radiation on cardiac pacemakers

    International Nuclear Information System (INIS)

    Salmi, J.; Malmivuo, J.A.V.

    1990-01-01

    Adverse effects of the ionizing and non-ionizing electromagnetic fields on five pacemaker models have been tested. The study consisted of three parts: 1. measurement of magnetic fields in a radiotherapy room (microtron MM14), 2. the application of non-ionizing electromagnetic fields on pacemakers in a test laboratory (1 ... 1000 μT, 10 ... 10 000 Hz), and 3. the application of ionizing radiation of different types of radiotherapy devices on the pacemakers. The magnetic field strength in the microtron treatment room was found to be under 7.5 μT, which is one order of magnitude lower than the tolerance level obtained for the pacemakers in the test laboratory. All the tested pacemakers tolerated the ionizing radiation dose levels (less than 60 Gy) which are used in the radiotherapy. (orig.) [de

  9. PEM fuel cell bipolar plate material requirements for transportation applications

    Energy Technology Data Exchange (ETDEWEB)

    Borup, R.L.; Stroh, K.R.; Vanderborgh, N.E. [Los Alamos National Lab., NM (United States)] [and others

    1996-04-01

    Cost effective bipolar plates are currently under development to help make proton exchange membrane (PEM) fuel cells commercially viable. Bipolar plates separate individual cells of the fuel cell stack, and thus must supply strength, be electrically conductive, provide for thermal control of the fuel stack, be a non-porous materials separating hydrogen and oxygen feed streams, be corrosion resistant, provide gas distribution for the feed streams and meet fuel stack cost targets. Candidate materials include conductive polymers and metal plates with corrosion resistant coatings. Possible metals include aluminium, titanium, iron/stainless steel and nickel.

  10. Tritium separation from light and heavy water by bipolar electrolysis

    International Nuclear Information System (INIS)

    Petek, M.; Ramey, D.W.; Taylor, R.D.

    1981-01-01

    Using multiple bipolar electrolytic separation of hydrogen isotopes with Pd-25%Ag electrodes, the mathematical feasibility of this method for tritium separation was shown and experimentally verified. Separation factors were measured on single bipolar electrodes and were found to be approximately equivalent to those associated with individual ordinary electrolytic systems. Multibipolar separations were experimentally achieved in single cascaded cells in which each bipolar electrode was of equal area to others in a series arrangement. Factors measured for multibipolar H-D separation were close to the values measured in single-stage cell measurements; for H-T separation, interstage leakage reduced the measured separation factor. However, in both cases separation of sufficient magnitude was achieved to show feasibility for real application to the extraction of tritium from large-volume systems at high current density. (author)

  11. Peripheral blood brain-derived neurotrophic factor in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, K; Vinberg, M; Kessing, L V

    2016-01-01

    Peripheral blood brain-derived neurotrophic factor (BDNF) has been proposed as a potential biomarker related to disease activity and neuroprogression in bipolar disorder, speculated to mirror alterations in brain expression of BDNF. The research area is rapidly evolving; however, recent...... investigations have yielded conflicting results with substantial variation in outcomes, highlighting the need to critically assess the state of current evidence. The aims of the study were to investigate differences in peripheral blood BDNF concentrations between bipolar disorder patients and healthy control...... subjects and between affective states in bipolar disorder patients, including assessment of the effect of treatment of acute episodes on BDNF levels. A systematic review of English language studies without considering publication status was conducted in PubMed (January 1950-November 2014), Embase (1974...

  12. Conductivity-limiting bipolar thermal conductivity in semiconductors

    Science.gov (United States)

    Wang, Shanyu; Yang, Jiong; Toll, Trevor; Yang, Jihui; Zhang, Wenqing; Tang, Xinfeng

    2015-01-01

    Intriguing experimental results raised the question about the fundamental mechanisms governing the electron-hole coupling induced bipolar thermal conduction in semiconductors. Our combined theoretical analysis and experimental measurements show that in semiconductors bipolar thermal transport is in general a “conductivity-limiting” phenomenon, and it is thus controlled by the carrier mobility ratio and by the minority carrier partial electrical conductivity for the intrinsic and extrinsic cases, respectively. Our numerical method quantifies the role of electronic band structure and carrier scattering mechanisms. We have successfully demonstrated bipolar thermal conductivity reduction in doped semiconductors via electronic band structure modulation and/or preferential minority carrier scatterings. We expect this study to be beneficial to the current interests in optimizing thermoelectric properties of narrow gap semiconductors. PMID:25970560

  13. Bipolar Transistors Can Detect Charge in Electrostatic Experiments

    Science.gov (United States)

    Dvorak, L.

    2012-01-01

    A simple charge indicator with bipolar transistors is described that can be used in various electrostatic experiments. Its behaviour enables us to elucidate links between 'static electricity' and electric currents. In addition it allows us to relate the sign of static charges to the sign of the terminals of an ordinary battery. (Contains 7 figures…

  14. Asymmetric bipolar membrane: A tool to improve product purity

    NARCIS (Netherlands)

    Balster, J.H.; Sumbharaju, R.; Srikantharajah, S.; Punt, Ineke G.M.; Stamatialis, Dimitrios; Jordan, V.; Wessling, Matthias

    2007-01-01

    Bipolar membranes (BPMs) are catalytic membranes for electro-membrane processes splitting water into protons and hydroxyl ions. To improve selectivity and current efficiency of BPMs, we prepare new asymmetric BPMs with reduced salt leakages. The flux of salt ions across a BPM is determined by the

  15. Do prehospital discharge pacemaker checks provide any additional clinical benefit?

    Science.gov (United States)

    Wheelan, Kevin R; Legge, Darlene M; Sakowski, Brent C; Bruce, Susan S; Roberts, David C; Johnston, L Murphy; Moore, B Jane; Beveridge, Thomas P; Wells, Peter J; Vallabahn, Ravi; Donsky, Michael S; Franklin, Jay O

    2005-08-01

    We performed a retrospective analysis of 250 records of consecutive, newly implanted, pacemaker patients from a single center to determine the rate of postimplant complications and observations discovered before and during the prehospital discharge evaluation. No observations occurred in 246 of 250 patients (98.4%) (1-sided 95% confidence interval 96.4%). Of the 250 patients, 4 had observations that were discovered at the prehospital discharge check and required reprogramming to increase the sensitivity safety margin (3 atrial and 1 ventricular). We documented only 1 complication that was discovered before the predischarge evaluation through telemetry and resulted in an atrial lead revision.

  16. The effects of gamma irradiation on neutron displacement sensitivity of lateral PNP bipolar transistors

    International Nuclear Information System (INIS)

    Wang, Chenhui; Chen, Wei; Liu, Yan; Jin, Xiaoming; Yang, Shanchao; Qi, Chao

    2016-01-01

    The effects of gamma irradiation on neutron displacement sensitivity of four types of lateral PNP bipolar transistors (LPNPs) with different neutral base widths, emitter widths and the doping concentrations of the epitaxial base region are studied. The physical mechanisms of the effects are explored by defect analysis using deep level transient spectroscopy (DLTS) techniques and numerical simulations of recombination process in the base region of the lateral PNP bipolar transistors, and are verified by the experiments on gate-controlled lateral PNP bipolar transistors (GCLPNPs) manufactured in the identical commercial bipolar process with different gate bias voltage. The results indicate that gamma irradiation increases neutron displacement damage sensitivity of lateral PNP bipolar transistors and the mechanism of this phenomenon is that positive charge induced by gamma irradiation enhances the recombination process in the defects induced by neutrons in the base region, leading to larger recombination component of base current and greater gain degradation.

  17. The effects of gamma irradiation on neutron displacement sensitivity of lateral PNP bipolar transistors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chenhui, E-mail: wangchenhui@nint.ac.cn; Chen, Wei; Liu, Yan; Jin, Xiaoming; Yang, Shanchao; Qi, Chao

    2016-09-21

    The effects of gamma irradiation on neutron displacement sensitivity of four types of lateral PNP bipolar transistors (LPNPs) with different neutral base widths, emitter widths and the doping concentrations of the epitaxial base region are studied. The physical mechanisms of the effects are explored by defect analysis using deep level transient spectroscopy (DLTS) techniques and numerical simulations of recombination process in the base region of the lateral PNP bipolar transistors, and are verified by the experiments on gate-controlled lateral PNP bipolar transistors (GCLPNPs) manufactured in the identical commercial bipolar process with different gate bias voltage. The results indicate that gamma irradiation increases neutron displacement damage sensitivity of lateral PNP bipolar transistors and the mechanism of this phenomenon is that positive charge induced by gamma irradiation enhances the recombination process in the defects induced by neutrons in the base region, leading to larger recombination component of base current and greater gain degradation.

  18. Complications of pacemaker therapy in adults with congenital heart disease: a multicenter study.

    Science.gov (United States)

    Opić, Petra; van Kranenburg, Matthijs; Yap, Sing-Chien; van Dijk, Arie P; Budts, Werner; Vliegen, Hubert W; van Erven, Lieselot; Can, Anil; Sahin, Gulhan; Theuns, Dominic A M J; Witsenburg, Maarten; Roos-Hesselink, Jolien W

    2013-10-09

    This study aims to investigate indications and complications of permanent cardiac pacing in adults with congenital heart disease (CHD). Two-hundred and seventy-four CHD patients were identified who underwent permanent pacemaker implantation between 1972 and 2009. The indication for pacing was acquired sinus node or AV node conduction disease (63%), sinus node or AV node conduction disease after cardiac surgery (28%), and drug/arrhythmia-related indications (9%). Patients with complex CHD received a pacemaker at younger age (23 versus 31 years, ppacemaker implantation (general population: 5.2%). The most common acute complications were lead dysfunction (4.0%), bleeding (2.6%), pocket infection (1.5%) and pneumothorax (1.5%). During a median follow-up of 12 years, pacemaker-related complications requiring intervention occurred in 95 patients (34.6%). The most common late pacemaker-related complications included lead failure (24.8%), pacemaker dysfunction/early battery depletion (5.1%), pacemaker migration (4.7%) and erosion (4.7%). Pacemaker implantation at younger age (pacemaker-related complication (adjusted hazard ratio 1.68, 95% confidence interval 1.07 to 2.63, p=0.023). The risk of periprocedural complications seems higher in the CHD population compared to the general population and more than one-third of CHD patients encountered a pacemaker-related complication during long-term follow-up. This risk increases for those who receive a pacemaker at younger age. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Radiotherapy for breast cancer and pacemaker; Radiotherapie pour un cancer du sein et stimulateur cardiaque

    Energy Technology Data Exchange (ETDEWEB)

    Menard, J.; Campana, F.; Bollet, M.A.; Dendale, R.; Fournier-Bidoz, N.; Marchand, V.; Mazal, A.; Fourquet, A.; Kirova, Y.M. [Oncologie-radiotherapie, institut Curie, 26, rue d' Ulm, 75005 Paris (France); Kirov, K.M.; Esteve, M. [Departement d' anesthesie-reanimation-douleur, institut Curie, 75005 Paris (France)

    2011-06-15

    Purpose. - Patients with permanent cardiac pacemakers occasionally require radiotherapy. Therapeutic Irradiation may cause pacemakers to malfunction due to the effects of ionizing radiation or electromagnetic interference. We studied the breast cancer patients who needed breast and/or chest wall and lymph node irradiation to assess the feasibility and tolerance in this population of patients. Patients and methods. - From November 2008 to December 2009, more than 900 patients received radiotherapy for their breast cancer in our department using megavoltage linear accelerator (X 4-6 MV and electrons). Among them, seven patients were with permanent pacemaker. All patients have been treated to the breast and chest wall and/or lymph nodes. Total dose to breast and/or chest wall was 50 Gy/25 fractions and 46 Gy/23 fractions to lymph nodes. Patients who underwent conserving surgery followed by breast irradiation were boosted when indicated to tumour bed with 16 Gy/8 fractions. All patients were monitored everyday in presence of radiation oncologist to follow the function of their pacemaker. All pacemakers were controlled before and after radiotherapy by the patients' cardiologist. Results. - Seven patients were referred in our department for postoperative breast cancer radiotherapy. Among them, only one patient was declined for radiotherapy and underwent mastectomy without radiotherapy. In four cases the pacemaker was repositioned before the beginning of radiotherapy. Six patients, aged between 48 and 84 years underwent irradiation for their breast cancer. Four patients were treated with conserving surgery followed by breast radiotherapy and two with mastectomy followed by chest wall and internal mammary chain, supra- and infra-clavicular lymph node irradiation. The dose to the pacemaker generator was kept below 2 Gy. There was no pacemaker dysfunction observed during the radiotherapy. Conclusion. - The multidisciplinary work with position change of the pacemaker

  20. Validity and reliability of the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) in Japanese patients with bipolar disorder.

    Science.gov (United States)

    Toyoshima, Kuniyoshi; Fujii, Yutaka; Mitsui, Nobuyuki; Kako, Yuki; Asakura, Satoshi; Martinez-Aran, Anabel; Vieta, Eduard; Kusumi, Ichiro

    2017-08-01

    In Japan, there are currently no reliable rating scales for the evaluation of subjective cognitive impairment in patients with bipolar disorder. We studied the relationship between the Japanese version of the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) and objective cognitive assessments in patients with bipolar disorder. We further assessed the reliability and validity of the COBRA. Forty-one patients, aged 16-64, in a remission period of bipolar disorder were recruited from Hokkaido University Hospital in Sapporo, Japan. The COBRA (Japanese version) and Frankfurt Complaint Questionnaire (FCQ), the gold standard in subjective cognitive assessment, were administered. A battery of neuropsychological tests was employed to measure objective cognitive impairment. Correlations among the COBRA, FCQ, and neuropsychological tests were determined using Spearman's correlation coefficient. The Japanese version of the COBRA had high internal consistency, good retest reliability, and concurrent validity-as indicated by a strong correlation with the FCQ. A significant correlation was also observed between the COBRA and objective cognitive measurements of processing speed. These findings are the first to demonstrate that the Japanese version of the COBRA may be clinically useful as a subjective cognitive impairment rating scale in Japanese patients with bipolar disorder. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  1. A pacemaker magnet check alone is sufficient for the majority of patients postpacemaker implant.

    Science.gov (United States)

    Jones, Michael A; Wong, Kelvin C K; Qureshi, Norman; Rajappan, Kim; Bashir, Yaver; Betts, Timothy R

    2014-12-01

    Patients postpacemaker implant can undergo a full assessment by pacing system programmer (PSP) or a magnet check. The former takes longer, but provides more detailed information; a magnet-mode assessment is faster, but provides only capture data in an asynchronous pacing mode. A magnet-mode assessment alone may be sufficient in most cases, and current clinical practice varies considerably. A retrospective single-center assessment of all pacemaker implants receiving PSP and magnet checks between September 2009 and April 2010. Patient records were reviewed. The results of PSP and magnet checks and any subsequent device-related management were noted. A total of 168 patients underwent pacemaker implantation, magnet-mode assessment, and then PSP interrogation during this period. Magnet-mode assessment revealed a problem in only one patient-failure of atrial capture, leading to subsequent atrial lead repositioning. None of the remaining 167 patients have a serious problem at PSP interrogation; six had minor issues at PSP check, none of which required repeat surgical intervention. The magnet-mode test only provides information on lead capture in an asynchronous pacing mode, which is the most essential data postoperatively. Our study has suggested that a magnet-mode assessment without PSP interrogation may be sufficient in the immediate postimplant assessment of these patients. Routine postimplant PSP interrogation is time consuming, labor intensive, and adds only minimal additional benefit to the safe management of these patients above and beyond a magnet check, coupled with informed assessment of the associated electrocardiogram/rhythm strip, clinical examination, and chest x-ray. ©2014 Wiley Periodicals, Inc.

  2. Bipolar Disorder and Alcoholism: Are They Related?

    Science.gov (United States)

    ... Are they related? Is there a connection between bipolar disorder and alcoholism? Answers from Daniel K. Hall-Flavin, M.D. Bipolar disorder and alcoholism often occur together. Although the association ...

  3. Bipolar outflow in B335

    International Nuclear Information System (INIS)

    Hirano, N.; Kameya, O.; Nakayama, M.; Takakubo, K.

    1988-01-01

    The high-velocity (C-12)O (J = 1-0) emission in B335 with a high angular resolution of 16 arcsec has been mapped. The high-velocity emission shows distinct bipolar pattern centered at IRAS 19345+0727, toward which a strong high-velocity (C-12)O emission has been detected. The bipolar lobes delineate remarkable collimation toward the IRAS source, indicating that the flow is focused within 0.02 pc of the driving source. Each lobe is accompanied by significant wing emission with the opposite velocity shift, which clearly shows the association with IRAS 19345+0727. This feature is well explained as a bipolar flow the axis of which is nearly perpendicular to the line of sight. There is no evidence of another evolved bipolar flow which does not associate with any dense core as previously suggested. This suggests that B335 is a site of very recent star formation, containing a single bipolar flow with an age of about 30,000 yr. 15 references

  4. Exercising control over bipolar disorder.

    Science.gov (United States)

    Malhi, Gin S; Byrow, Yulisha

    2016-11-01

    Following extensive research exercise has emerged as an effective treatment for major depressive disorder, and it is now a recognised therapy alongside other interventions. In contrast, there is a paucity of research examining the therapeutic effects of exercise for those with bipolar disorder. Given that dysfunctional reward processing is central to bipolar disorder, research suggests that exercise can perhaps be framed as a reward-related event that may have the potential to precipitate a manic episode. The behavioural activation system (BAS) is a neurobehavioural system that is associated with responding to reward and provides an appropriate framework to theoretically examine and better understand the effects of exercise treatment on bipolar disorder. This article discusses recent research findings and provides an overview of the extant literature related to the neurobiological underpinnings of BAS and exercise as they relate to bipolar disorder. This is important clinically because depending on mood state in bipolar disorder, we postulate that exercise could be either beneficial or deleterious with positive or negative effects on the illness. Clearly, this complicates the evaluation of exercise as a potential treatment in terms of identifying its optimal characteristics in this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  5. Late Onset Bipolar Disorder: Case Report

    OpenAIRE

    Filipa Araújo; Adriana Horta

    2016-01-01

    Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1%) in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old) with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad different...

  6. An electromagnetic compatibility study of cardiac pacemaker to low frequency interferences

    International Nuclear Information System (INIS)

    Andretzko, J.P.; Hedjiedj, A.; Babouri, A.; Guendouz, L.; Nadi, M.

    2006-01-01

    This paper presents an experimental study of the behaviour of cardiac pacemaker submitted to low frequency electromagnetic interferences. The method used in this study is progressive. It consists in starting from the target (the cardiac pacemaker), identifying and quantifying the disturbances (the source), and then introducing secondary influencing parameters in stepwise fashion. The general problematic consists in checking this immunity in relation with led disruptions and in relation with beaming disruptions. The experimental approach suggests two kind of tests corresponding to the two studied coupling modes. The first one corresponds to a direct applying of the disruptive signal between the pacemaker terminals. The objective of this phase is to determine the characteristics of the signal (amplitude and frequency) which are detected by the pacemaker and which generate modifications of its operation. In the second phase the pacemaker is subjected to a variable low frequency magnetic field. This last interacts with the pacemaker by inductive coupling through the loop formed by the pacemaker and its leads and the surrounding medium. This interaction results in an induced electromotive force between the terminals of the pacemaker which can potentially disturb the operation of this last. The objective of this phase is to characterize the signal (magnetic field) likely to generate these disturbances. Tests are carried out on six single chamber pacemaker and five dual chamber pacemaker. The interfering signal frequencies are 50 Hz, 60 Hz, 10 khz and 25 khz. Tracking and programming of the pacemaker housing is achieved with the telemetry system. In this study, the devices have all been configured in inhibited stimulation (S.S.I. or V.V.I. mode according to the international codification), this configuration being the most widespread. The housing stimulates the basic frequency in the absence o f intrinsic activity, the stimulation can be inhibited in each chamber by a

  7. An electromagnetic compatibility study of cardiac pacemaker to low frequency interferences

    Energy Technology Data Exchange (ETDEWEB)

    Andretzko, J.P.; Hedjiedj, A.; Babouri, A.; Guendouz, L.; Nadi, M. [Nancy-1 Univ. Henri Poincare, Lab. d' Instrumentation Electronique de Nancy, Faculte des Sciences, 54 - Vandoeuvre les Nancy (France)

    2006-07-01

    This paper presents an experimental study of the behaviour of cardiac pacemaker submitted to low frequency electromagnetic interferences. The method used in this study is progressive. It consists in starting from the target (the cardiac pacemaker), identifying and quantifying the disturbances (the source), and then introducing secondary influencing parameters in stepwise fashion. The general problematic consists in checking this immunity in relation with led disruptions and in relation with beaming disruptions. The experimental approach suggests two kind of tests corresponding to the two studied coupling modes. The first one corresponds to a direct applying of the disruptive signal between the pacemaker terminals. The objective of this phase is to determine the characteristics of the signal (amplitude and frequency) which are detected by the pacemaker and which generate modifications of its operation. In the second phase the pacemaker is subjected to a variable low frequency magnetic field. This last interacts with the pacemaker by inductive coupling through the loop formed by the pacemaker and its leads and the surrounding medium. This interaction results in an induced electromotive force between the terminals of the pacemaker which can potentially disturb the operation of this last. The objective of this phase is to characterize the signal (magnetic field) likely to generate these disturbances. Tests are carried out on six single chamber pacemaker and five dual chamber pacemaker. The interfering signal frequencies are 50 Hz, 60 Hz, 10 khz and 25 khz. Tracking and programming of the pacemaker housing is achieved with the telemetry system. In this study, the devices have all been configured in inhibited stimulation (S.S.I. or V.V.I. mode according to the international codification), this configuration being the most widespread. The housing stimulates the basic frequency in the absence o f intrinsic activity, the stimulation can be inhibited in each chamber by a

  8. Imunologia do transtorno bipolar Immunology of bipolar disorder

    Directory of Open Access Journals (Sweden)

    Izabela Guimarães Barbosa

    2009-01-01

    Full Text Available OBJETIVO: Pesquisas recentes têm implicado fatores imunes na patogênese de diversos transtornos neuropsiquiátricos. O objetivo do presente trabalho é revisar os trabalhos que investigaram a associação entre transtorno bipolar e alterações em parâmetros imunes. MÉTODOS: Artigos que incluíam as palavras-chave: "bipolar disorder", "mania", "immunology", "cytokines", "chemokines", "interleukins", "interferon" e "tumor necrosis factor" foram selecionados em uma revisão sistemática da literatura. As bases de dados avaliadas foram MedLine e Scopus, entre os anos de 1980 e 2008. RESULTADOS: Foram identificados 28 trabalhos que estudaram alterações imunes em pacientes com transtorno bipolar. Seis artigos investigaram genes relacionados à resposta imune; cinco, autoanticorpos; quatro, populações leucocitárias; 13, citocinas e/ou moléculas relacionadas à resposta imune e seis, leucócitos de pacientes in vitro. CONCLUSÕES: Embora haja evidências na literatura correlacionando o transtorno bipolar a alterações imunes, os dados não são conclusivos. O transtorno bipolar parece estar associado a níveis mais elevados de autoanticorpos circulantes, assim como à tendência à ativação imune com produção de citocinas pró-inflamatórias e redução de parâmetros anti-inflamatórios.OBJECTIVE: Emerging research has implicated immune factors in the pathogenesis of a variety of neuropsychiatric disorders. The objective of the present paper is to review the studies that investigated the association between bipolar disorder and immune parameters. METHODS: Papers that included the keywords "bipolar to disorder", "mania", "immunology", "cytokines", "chemokines", "interleukins", "interferon" and "tumor necrosis factor" were selected in a systematic review of the literature. The evaluated databases were MedLine and Scopus in the period between 1980 and 2008. RESULTS: Twenty eight works were found. Six studies investigated immune response

  9. Posibilities of cardiac pacemaker use in paroxsysmal atrial fibrilation

    Directory of Open Access Journals (Sweden)

    Borut Kamenik

    2005-12-01

    Full Text Available Background: Prevention of atrial fibrillation is a big therapeutic challenge because of all known negative consequences of this the most frequent cardiac arrhythmia. Numerous of clinical studies showed bad control or ineffectiveness of antiarhythmic drugs. Nonfarmakological therapies like surgical treatment, radiofrequency ablation and atrial pacing are being tested. Effectiveness of atrial pacing in prevention of paroxysmal artial fibrillation has been documented in numerous prospective studies and is effective for a long time interval, but only for patients with bradicardic underlying cardiac rhythm. In Normocardic rhythm or normal AV conduction the effective Atrial fibrillation prevention was not proven. The mechanism of action is based on premature atrial complex suppression, reduction of dispersion of refractoriness after short-long cycles and reduction of interatrial conduction delay. The atrial stimulation site or multi-site atrial pacing could be effective in AF prevention when interatrial conduction delay is present; otherwise the difference is not significant.Conclusions: In bradicardic patient who has frequent paroxysms of atrial fibrillation, regardless if bradycardia is due to ineffective antiarrhythmic drug treathement, implantation of DDDR pacemaker with atrial prevention algorhythm is indicated. If the P-wave duration is >120 milliseconds multi-site atrial pacing or septal atrial pacing should be considered. Pacemaker diagnostic tools could be used for adequate start of anticoagulant therapy and control of effectiveness of anthyarhythmic drug therapy.

  10. Efficacy of postoperative prophylactic antibiotics in reducing permanent pacemaker infections.

    Science.gov (United States)

    Lee, Wen-Huang; Huang, Ting-Chun; Lin, Li-Jen; Lee, Po-Tseng; Lin, Chih-Chan; Lee, Cheng-Han; Chao, Ting-Hsing; Li, Yi-Heng; Chen, Ju-Yi

    2017-08-01

    Despite limited evidence, postoperative prophylactic antibiotics are often used in the setting of permanent pacemaker implantation or replacement. The aim of this study is to investigate the efficacy of postoperative antibiotics. Postoperative prophylactic antibiotics may be not clinically useful. We recruited 367 consecutive patients undergoing permanent pacemaker implantation or generator replacement at a tertiary referral center. Baseline demographics, clinical characteristics, and procedure information were collected, and all patients received preoperative prophylactic antibiotics. Postoperative prophylactic antibiotics were administered at the discretion of the treating physician, and all patients were seen in follow-up every 3 to 6 months for an average follow-up period of 16 months. The primary endpoint was device-related infection. A total of 110 patients were treated with preoperative antibiotics only (group 1), whereas 257 patients received both preoperative and postoperative antibiotics (group 2). After a mean follow-up period of 16 months, 1 patient in group 1 (0.9%) and 4 patients in group 2 (1.5%) experienced a device-related infection. There was no significant difference in the rate of infection between the 2 groups (P = 0.624). In the univariate analysis, only the age (60 ± 11 vs 75 ± 12 years, P antibiotics had a similar rate of infection as those treated with preoperative antibiotics alone. Further studies are needed to confirm these preliminary findings. © 2017 Wiley Periodicals, Inc.

  11. High-performance silicon nanowire bipolar phototransistors

    Science.gov (United States)

    Tan, Siew Li; Zhao, Xingyan; Chen, Kaixiang; Crozier, Kenneth B.; Dan, Yaping

    2016-07-01

    Silicon nanowires (SiNWs) have emerged as sensitive absorbing materials for photodetection at wavelengths ranging from ultraviolet (UV) to the near infrared. Most of the reports on SiNW photodetectors are based on photoconductor, photodiode, or field-effect transistor device structures. These SiNW devices each have their own advantages and trade-offs in optical gain, response time, operating voltage, and dark current noise. Here, we report on the experimental realization of single SiNW bipolar phototransistors on silicon-on-insulator substrates. Our SiNW devices are based on bipolar transistor structures with an optically injected base region and are fabricated using CMOS-compatible processes. The experimentally measured optoelectronic characteristics of the SiNW phototransistors are in good agreement with simulation results. The SiNW phototransistors exhibit significantly enhanced response to UV and visible light, compared with typical Si p-i-n photodiodes. The near infrared responsivities of the SiNW phototransistors are comparable to those of Si avalanche photodiodes but are achieved at much lower operating voltages. Compared with other reported SiNW photodetectors as well as conventional bulk Si photodiodes and phototransistors, the SiNW phototransistors in this work demonstrate the combined advantages of high gain, high photoresponse, low dark current, and low operating voltage.

  12. Mathematical models of bipolar disorder

    Science.gov (United States)

    Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Troyer, Jessica; Wirkus, Stephen; Porter, Mason A.

    2009-07-01

    We use limit cycle oscillators to model bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about 1% of the United States adult population. We consider two non-linear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using weakly-coupled, weakly-damped harmonic oscillators. We discuss how the proposed models can be used as a framework for refined models that incorporate additional biological data. We conclude with a discussion of possible generalizations of our work, as there are several biologically-motivated extensions that can be readily incorporated into the series of models presented here.

  13. Is bipolar always bipolar? Understanding the controversy on bipolar disorder in children

    Science.gov (United States)

    Grimmer, Yvonne; Hohmann, Sarah

    2014-01-01

    Dramatically increasing prevalence rates of bipolar disorder in children and adolescents in the United States have provoked controversy regarding the boundaries of manic symptoms in child and adolescent psychiatry. The serious impact of this ongoing debate on the treatment of affected children is reflected in the concomitant increase in prescription rates for antipsychotic medication. A key question in the debate is whether this increase in bipolar disorder in children and adolescents is based on a better detection of early-onset bipolar disorder—which can present differently in children and adolescents—or whether it is caused by an incorrect assignment of symptoms which overlap with other widely known disorders. So far, most findings suggest that the suspected symptoms, in particular chronic, non-episodic irritability (a mood symptom presenting with easy annoyance, temper tantrums and anger) do not constitute a developmental presentation of childhood bipolar disorder. Additional research based on prospective, longitudinal studies is needed to further clarify the developmental trajectories of bipolar disorder and the diagnostic status of chronic, non-episodic irritability. PMID:25580265

  14. Outcome and management of pacemaker-induced superior vena cava syndrome.

    Science.gov (United States)

    Fu, Hai-Xia; Huang, Xin-Miao; Zhong, Li; Osborn, Michael J; Bjarnason, Haraldur; Mulpuru, Siva; Zhao, Xian-Xian; Friedman, Paul A; Cha, Yong-Mei

    2014-11-01

    We aimed to determine the long-term outcomes of percutaneous lead extraction and stent placement in patients with pacemaker-induced superior vena cava (SVC) syndrome. The study retrospectively screened patients who underwent lead extraction followed by central vein stent implantation at Mayo Clinic (Rochester, MN, USA), from January 2005 to December 2012, to identify the patients with pacemaker-induced SVC syndrome. Demographic, clinical, and follow-up characteristics of those patients were collected from electronic medical records. Six cases were identified. The mean (standard deviation) age was 56 (15) years (male, 67%). All patients had permanent dual-chamber pacemakers, with a mean 11-year history of pacemaker placement. The entire device system was explanted in five patients; one patient had a 21-year-old pacemaker lead that could not be removed. Eight stents were implanted in six patients: five patients had one stent, one patient had three. A new pacemaker system was reimplanted through the stented vein in five patients. Technical success was achieved in all patients, without any complication. Symptoms rapidly resolved in all patients after stent deployment. The mean follow-up duration was 48 months (range, 10-100 months). Three patients remained symptom free. Reintervention with percutaneous balloon venoplasty was successful in three patients with symptom recurrence. Percutaneous stent implantation after lead removal followed by reimplantation of leads is a feasible alternative therapy for pacemaker-induced SVC syndrome, although some cases may require repeat intervention. ©2014 Wiley Periodicals, Inc.

  15. Tricuspid valve repair for severe tricuspid regurgitation due to pacemaker leads.

    Science.gov (United States)

    Uehara, Kyokun; Minakata, Kenji; Watanabe, Kentaro; Sakaguchi, Hisashi; Yamazaki, Kazuhiro; Ikeda, Tadashi; Sakata, Ryuzo

    2016-07-01

    Tricuspid valve regurgitation due to pacemaker leads is a well-known complication. Although some reports have suggested that pacemaker leads should be surgically explanted, strongly adhered leads cannot always be removed. The aim of this study was to describe our tricuspid valve repair techniques with pacemaker leads left in situ. Our retrospective study investigated 6 consecutive patients who required tricuspid valve surgery for severe regurgitation induced by pacemaker leads. From the operative findings, we identified 3 patterns of tricuspid valve and pacemaker lead involvement. In 3 patients, the leads were caught in the chordae, in 2 patients, tricuspid regurgitation was caused by lead impingement on the septal leaflet, and in 3 patients, tricuspid valve leaflets had been perforated by the pacemaker leads. During surgery, all leads were left in situ after being separated from the leaflet or valvular apparatus. In addition, suture annuloplasty was performed for annular dilatation in all cases. In one patient, the lead was reaffixed to the annulus after the posterior leaflet was cut back towards the annulus, and the leaflet was then closed. There was one hospital death due to sepsis. The degree of tricuspid regurgitation was trivial in all surviving patients at discharge. During a mean follow-up of 21 months, one patient died from pneumonia 20 months after tricuspid valve repair. In patients undergoing tricuspid valve surgery due to severe tricuspid regurgitation caused by pacemaker leads, the leads can be left in situ after proper repair with annuloplasty. © The Author(s) 2016.

  16. Rhabdomyosarcoma associated with the lead wire of a pacemaker generator implant.

    Science.gov (United States)

    Thieman Mankin, Kelley M; Dunbar, Mark D; Toplon, David; Ginn, Pamela; Maisenbacher, Herbert W; Risselada, Marije

    2014-06-01

    An 11-year-old female spayed Labrador Retriever was presented for a draining, painful subcutaneous mass palpated over a previously implanted pacemaker generator. Infection was suspected and the mass was removed surgically. On cut surface, the mass was friable and mottled tan to brown with firm pale tan nodules, surrounding the pacemaker lead wire adjacent to the pacemaker generator. Cytologic interpretation of impression smears was consistent with a sarcoma, and suggestive of a rhabdomyosarcoma due to the presence of strap-like cells. On histopathologic examination, a highly invasive nodular mass surrounded the pacemaker lead, composed of pleomorphic round, spindle and strap cells, and multinucleated giant cells. The population exhibited microscopic invasion into the deep portion of the fibrous capsule surrounding the pacemaker generator. There were tumor emboli within small to medium subcutaneous veins adjacent to the mass. Immunohistochemically, the neoplastic cells stained positive for α-sarcomeric actin and vimentin, and negative for α-smooth muscle actin, consistent with a rhabdomyosarcoma arising at the site of the pacemaker generator. To our knowledge, this is the first report of a rhabdomyosarcoma associated with the lead wire of a pacemaker generator in a dog. © 2014 American Society for Veterinary Clinical Pathology and European Society for Veterinary Clinical Pathology.

  17. Transvenous permanent pacemaker implantation in dextrocardia: technique, challenges, outcome, and a brief review of literature.

    Science.gov (United States)

    Shenthar, Jayaprakash; Rai, Maneesh K; Walia, Rohit; Ghanta, Somasekhar; Sreekumar, Praveen; Reddy, Satish S

    2014-09-01

    Dextrocardia is a rare congenital anomaly. Pacemaker implantation in dextrocardia can be challenging because of the distorted anatomy and associated anomalies. The literature regarding implantation of pacemaker in dextrocardia is scarce. The study involved retrospective analysis of records of patients with dextrocardia who had undergone pacemaker implantation between January 2006 and July 2013 from a single centre. Six patients with dextrocardia (five males and one female) underwent permanent pacemaker implantation (PPI) between January 2006 and July 2013. Of them, three had situs solitus dextrocardia and three situs inversus dextrocardia. All three patients with situs solitus dextrocardia had associated corrected transposition of great arteries. The indication for pacemaker implantation was symptomatic complete atrioventricular (AV) block in four, high-grade AV block in one, and sinus node dysfunction in one patient. A favourable outcome was noted during a mean follow-up of 3.9 years (4 months to 7 years) with one patient needing a pulse generator replacement. Permanent pacemaker implantation in dextrocardia can be challenging because of the distorted anatomy. Use of a technique employing angiography to delineate chamber anatomy and relationship can assist the operator during such difficult PPIs. The medium- and long-term survival after a successful pacemaker implantation in dextrocardia is favourable. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  18. Evaluation of cumulative effects of MR imaging on pacemaker systems at 1.5 Tesla.

    Science.gov (United States)

    Naehle, Claas P; Zeijlemaker, Volkert; Thomas, Daniel; Meyer, Carsten; Strach, Katharina; Fimmers, Rolf; Schild, Hans; Sommer, Torsten

    2009-12-01

    The purpose of this study was to evaluate possible cumulative effects of repeated magnetic resonance imaging (MRI) examinations on pacemaker systems in patients with cardiac pacemakers. The records of pacemaker patients who underwent repetitive MRI examinations in our institution were reviewed to identify patients who underwent two or more MRI examinations at 1.5T of any anatomical region. Using these criteria, a total of 47 patients who underwent a total 171 MRI examinations were identified and included in this study. Institutional Review Board approval for all pacemaker investigations was obtained. Written informed consent was obtained from all patients. Pacemakers were interrogated immediately before and after MR imaging, and after 3 months, including measurement of pacing capture threshold (PCT), lead impedance (LI), and battery voltage (BV). PCT, LI, and BV were analyzed for changes dependant on the number of MRI exams performed. Mean changes over time and changes between first and last pacemaker interrogation of PCT, LI, and BV were calculated. A statistically significant (P < 0.05), but clinically irrelevant trend for decrease in PCT and BV was found. No significant or clinically relevant changes in LI were observed. In this first study, no clinically relevant, cumulative changes in PCT, LI, or BV could be detected in PM patients who underwent two or more MRI examinations. However, a careful benefit/risk evaluation, among other MRI- and pacemaker-related safety precautions, remains mandatory, as clinically relevant alterations to the PM system cannot be excluded by all means.

  19. Pacemaker reed switch behavior in 0.5, 1.5, and 3.0 Tesla magnetic resonance imaging units: are reed switches always closed in strong magnetic fields?

    Science.gov (United States)

    Luechinger, Roger; Duru, Firat; Zeijlemaker, Volkert A; Scheidegger, Markus B; Boesiger, Peter; Candinas, Reto

    2002-10-01

    MRI is established as an important diagnostic tool in medicine. However, the presence of a cardiac pacemaker is usually regarded as a contraindication for MRI due to safety reasons. The aim of this study was to investigate the state of a pacemaker reed switch in different orientations and positions in the main magnetic field of 0.5-, 1.5-, and 3.0-T MRI scanners. Reed switches used in current pacemakers and ICDs were tested in 0.5-, 1.5-, and 3.0-T MRI scanners. The closure of isolated reed switches was evaluated for different orientations and positions relative to the main magnetic field. The field strengths to close and open the reed switch and the orientation dependency of the closed state inside the main magnetic field were investigated. The measurements were repeated using two intact pacemakers to evaluate the potential influence of the other magnetic components, like the battery. If the reed switches were oriented parallel to the magnetic fields, they closed at 1.0 +/- 0.2 mT and opened at 0.7 +/- 0.2 mT. Two different reed switch behaviors were observed at different magnetic field strengths. In low magnetic fields ( 200 mT), the reed switches opened in 50% of all tested orientations. No difference between the three scanners could be demonstrated. The reed switches showed the same behavior whether they were isolated or an integral part of the pacemakers. The reed switch in a pacemaker or an ICD does not necessarily remain closed in strong magnetic fields at 0.5, 1.5, or 3.0 T and the state of the reed switch may not be predictable with certainty in clinical situations.

  20. An update on adjunctive treatment options for bipolar disorder.

    Science.gov (United States)

    Dean, Olivia M; Gliddon, Emma; Van Rheenen, Tamsyn E; Giorlando, Francesco; Davidson, Sandra K; Kaur, Manreena; Ngo, Trung T; Williams, Lana J

    2018-03-01

    Bipolar disorder is a complex illness often requiring combinations of therapies to successfully treat symptoms. In recent years, there have been significant advancements in a number of therapies for bipolar disorder. It is therefore timely to provide an overview of current adjunctive therapeutic options to help treating clinicians to inform their patients and work towards optimal outcomes. Publications were identified from PubMed searches on bipolar disorder and pharmacotherapy, nutraceuticals, hormone therapy, psychoeducation, interpersonal and social rhythm therapy, cognitive remediation, mindfulness, e-Health and brain stimulation techniques. Relevant articles in these areas were selected for further review. This paper provides a narrative review of adjunctive treatment options and is not a systematic review of the literature. A number of pharmacotherapeutic, psychological and neuromodulation treatment options are available. These have varying efficacy but all have shown benefit to people with bipolar disorder. Due to the complex nature of treating the disorder, combination treatments are often required. Adjunctive treatments to traditional pharmacological and psychological therapies are proving useful in closing the gap between initial symptom remission and full functional recovery. Given that response to monotherapy is often inadequate, combination regimens for bipolar disorder are typical. Correspondingly, psychiatric research is working towards a better understanding of the disorder's underlying biology. Therefore, treatment options are changing and adjunctive therapies are being increasingly recognized as providing significant tools to improve patient outcomes. Towards this end, this paper provides an overview of novel treatments that may improve clinical outcomes for people with bipolar disorder. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Neuroleptic-induced deficit syndrome in bipolar disorder with psychosis

    Directory of Open Access Journals (Sweden)

    Ueda S

    2016-02-01

    Full Text Available Satoshi Ueda,1 Takeshi Sakayori,1 Ataru Omori,2 Hajime Fukuta,3 Takashi Kobayashi,3 Kousuke Ishizaka,1 Tomoyuki Saijo,4 Yoshiro Okubo1 1Department of Neuropsychiatry, Nippon Medical School, Tokyo, Japan; 2Tamachuo Hospital, Tokyo, Japan; 3Kurumegaoka Hospital, Tokyo, Japan; 4Saijo Clinic, Tokyo, Japan Abstract: Neuroleptics can induce not only physical adverse effects but also mental effects that produce deficit status in thought, affect, cognition, and behavior. This condition is known as neuroleptic-induced deficit syndrome (NIDS, which includes apathy, lack of initiative, anhedonia, indifference, blunted affect, and reduced insight into disease. Although this old concept now appears almost forgotten, neuroleptics, whether typical or atypical, can make depression or bipolar disorder resemble other more refractory conditions, readily leading to mistaken diagnosis and inappropriate treatment. The authors describe three cases of NIDS superimposed on depressive phase in bipolar disorder with psychosis, where the attending psychiatrist’s failure to recognize NIDS prevented patients from receiving effective treatment and achieving remission. All cases achieved remission after reduction of neuroleptics and intensive therapy, including electroconvulsive therapy, for bipolar depression. The concept of NIDS was originally introduced for schizophrenia, and it has rarely been highlighted in other diseases. In recent years, however, atypical antipsychotics are being more often administered to patients with bipolar disorder. Psychiatrists, therefore, should also remember and exercise caution regarding NIDS in the pharmacotherapy of bipolar disorder with and without psychosis. The authors believe that the concept of NIDS needs to be reappraised in current psychiatry. Keywords: neuroleptic-induced deficit syndrome (NIDS, bipolar disorder, psychosis, atypical antipsychotics, electroconvulsive therapy

  2. Bipolar dislocation of the clavicle

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2012-01-01

    Full Text Available Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup.

  3. Transcultural aspects of bipolar disorder

    OpenAIRE

    Sanches, Marsal; Jorge, Miguel Roberto

    2004-01-01

    Considerando-se que existem diferenças importantes na maneira como as emoções são vivenciadas e expressas em diferentes culturas, a apresentação e o manejo do transtorno afetivo bipolar sofrem influência de fatores culturais. O presente artigo realiza uma breve revisão da evidência referente aos aspectos transculturais do transtorno bipolar.Cultural variations in the expression of emotions have been described. Consequently, there are cross-cultural influences on the diagnosis and management o...

  4. Positive Traits in the Bipolar Spectrum: The Space between Madness and Genius

    Science.gov (United States)

    Greenwood, Tiffany A.

    2017-01-01

    Bipolar disorder is a severe, lifelong mood disorder for which little is currently understood of the genetic mechanisms underlying risk. By examining related dimensional phenotypes, we may further our understanding of the disorder. Creativity has a historical connection with the bipolar spectrum and is particularly enhanced among unaffected first-degree relatives and those with bipolar spectrum traits. This suggests that some aspects of the bipolar spectrum may confer advantages, while more severe expressions of symptoms negatively influence creative accomplishment. Creativity is a complex, multidimensional construct with both cognitive and affective components, many of which appear to reflect a shared genetic vulnerability with bipolar disorder. It is suggested that a subset of bipolar risk variants confer advantages as positive traits according to an inverted-U-shaped curve with clinically unaffected allele carriers benefitting from the positive traits and serving to maintain the risk alleles in the population. The association of risk genes with creativity in healthy individuals (e.g., NRG1), as well as an overall sharing of common genetic variation between bipolar patients and creative individuals, provides support for this model. Current findings are summarized from a multidisciplinary perspective to demonstrate the feasibility of research in this area to reveal the mechanisms underlying illness. PMID:28277566

  5. Twiddler-syndrom er en årsag til pacemaker elektrode displacering

    DEFF Research Database (Denmark)

    Grønbech, Keea Treu; Hansen, Michael Gilså

    2013-01-01

    Twiddler's syndrome is a rare cause of pacemaker electrode displacement. The displacement is caused by the patient's manipulation with the pacemaker, so the electrode is retracted. We describe a case of a 79-year-old overweight woman with a known psychiatric anamnesis, who was admitted twice...... with twiddler's syndrome. Age and overweight are known risk factors for twiddler's syndrome; and in this case the patient's psychiatric habitus was probably an additional risk factor. Before performing a pacemaker implantation it is important to take the patient's risk factors into account, and thus consider...

  6. W/kit gene required for interstitial cells of Cajal and for intestinal pacemaker activity

    DEFF Research Database (Denmark)

    Huizinga, J D; Thuneberg, L; Klüppel, M

    1995-01-01

    The pacemaker activity in the mammalian gut is responsible for generating anally propagating phasic contractions. The cellular basis for this intrinsic activity is unknown. The smooth muscle cells of the external muscle layers and the innervated cellular network of interstitial cells of Cajal......, which is closely associated with the external muscle layers of the mammalian gut, have both been proposed to stimulate pacemaker activity. The interstitial cells of Cajal were identified in the last century but their developmental origin and function have remained unclear. Here we show...... of Cajal associated with Auerbach's nerve plexus and intestinal pacemaker activity....

  7. Enhancement of Spontaneous Activity by HCN4 Overexpression in Mouse Embryonic Stem Cell-Derived Cardiomyocytes - A Possible Biological Pacemaker.

    Directory of Open Access Journals (Sweden)

    Yukihiro Saito

    Full Text Available Establishment of a biological pacemaker is expected to solve the persisting problems of a mechanical pacemaker including the problems of battery life and electromagnetic interference. Enhancement of the funny current (If flowing through hyperpolarization-activated cyclic nucleotide-gated (HCN channels and attenuation of the inward rectifier K+ current (IK1 flowing through inward rectifier potassium (Kir channels are essential for generation of a biological pacemaker. Therefore, we generated HCN4-overexpressing mouse embryonic stem cells (mESCs and induced cardiomyocytes that originally show poor IK1 currents, and we investigated whether the HCN4-overexpressing mESC-derived cardiomyocytes (mESC-CMs function as a biological pacemaker in vitro.The rabbit Hcn4 gene was transfected into mESCs, and stable clones were selected. mESC-CMs were generated via embryoid bodies and purified under serum/glucose-free and lactate-supplemented conditions. Approximately 90% of the purified cells were troponin I-positive by immunostaining. In mESC-CMs, expression level of the Kcnj2 gene encoding Kir2.1, which is essential for generation of IK1 currents that are responsible for stabilizing the resting membrane potential, was lower than that in an adult mouse ventricle. HCN4-overexpressing mESC-CMs expressed about a 3-times higher level of the Hcn4 gene than did non-overexpressing mESC-CMs. Expression of the Cacna1h gene, which encodes T-type calcium channel and generates diastolic depolarization in the sinoatrial node, was also confirmed. Additionally, genes required for impulse conduction including Connexin40, Connexin43, and Connexin45 genes, which encode connexins forming gap junctions, and the Scn5a gene, which encodes sodium channels, are expressed in the cells. HCN4-overexpressing mESC-CMs showed significantly larger If currents and more rapid spontaneous beating than did non-overexpressing mESC-CMs. The beating rate of HCN4-overexpressing mESC-CMs responded

  8. Clinical Guidelines on Long-Term Pharmacotherapy for Bipolar Disorder in Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Joanna H. Cox

    2014-01-01

    Full Text Available Bipolar disorder is a severe affective disorder which can present in adolescence, or sometimes earlier, and often requires a pharmacotherapeutic approach. The phenomenology of bipolar disorder in children and adolescents appears to differ from that of adult patients, prompting the need for specific pharmacotherapy guidelines for long-term management in this patient population. Current treatment guidelines were mainly developed based on evidence from studies in adult patients, highlighting the requirement for further research into the pharmacotherapy of children and adolescents with bipolar disorder. This review compares and critically analyzes the available guidelines, discussing the recommended medication classes, their mechanisms of action, side effect profiles and evidence base.

  9. Social support and bipolar disorder

    Directory of Open Access Journals (Sweden)

    Paula Mendonça Studart

    2015-08-01

    Full Text Available Background Bipolar disorder is a chronic condition that affects the functioning of its carriers in many different ways, even when treated properly. Therefore, it’s also important to identify the psychosocial aspects that could contribute to an improvement of this population’s quality of life.Objective Carry out a literature review on the role of social support in cases of bipolar disorder.Method A research on the following online databases PubMed, Lilacs and SciELO was conducted by using the keywords “social support” or “social networks” and “mood disorders” or “bipolar disorder” or “affective disorder,” with no defined timeline.Results Only 13 studies concerning the topic of social support and BD were found in the search for related articles. Generally speaking, the results show low rates of social support for BD patients.Discussion Despite the growing interest in the overall functioning of patients with bipolar disorder, studies on social support are still rare. Besides, the existing studies on the subject use different methodologies, making it difficult to establish data comparisons.

  10. Electronic monitoring in bipolar disorder

    DEFF Research Database (Denmark)

    Faurholt-Jepsen, Maria

    2018-01-01

    generated data (e.g. the number of text messages sent/day; the number of incoming and outgoing calls/day; the number of changes in cell tower IDs/day; and voice features) seem to reflect clinically assessed depressive and manic symptoms in bipolar disorder; 3) smartphone-based electronic self-monitoring had...

  11. Saline-enhanced hepatic radiofrequency ablation using a perfused-cooled electrode: comparison of dual probe bipolar mode with monopolar and single probe bipolar modes

    International Nuclear Information System (INIS)

    Lee, Jeong Min; Han, Joon Koo; Kim, Se Hyung; Lee, Jae Young; Kim, Dae Jin; Lee, Min Woo; Cho, Gyung Goo; Han, Chang Jin; Choi, Byung Ihn

    2004-01-01

    To determine whether saline-enhanced dual probe bipolar radiofrequency ablation (RFA) using perfused-cooled electrodes shows better in-vitro efficiency than monopolar or single probe bipolar RFA in creating larger coagulation necrosis. RF was applied to excised bovine livers in both bipolar and monopolar modes using a 200W generator (CC-3; Radionics) and the perfused-cooled electrodes for 10 mins. After placing single or double perfused-cooled electrodes in the explanted liver, 30 ablation zones were created at three different regimens: group A; saline-enhanced monopolar RFA, group B; saline-enhanced single probe bipolar RFA, and group C; saline-enhanced dual probe bipolar RFA. During RFA, we measured the tissue temperature at 15mm from the electrode. The dimensions of the ablation zones and changes in the impedance currents and liver temperature during RFA were then compared between the groups. The mean current values were higher for monopolar mode (group A) than for the bipolar modes (group B and C): 1550 ± 25 mA in group A, 764 ±189 mA in group B and 819 ± 98 mA in group C(ρ 3 in group A, 23.7 ±3.8 cm 3 in group B, and 34.2 ± 5.1 cm 3 in group C(ρ 0.05). The temperature at 15 mm from the electrode was higher in group C than in the other groups: 70 ± 18 .deg. C in group A, 59 ± 23 .deg. C in group B and 96 ± 16 .deg. C in group C (ρ < 0.05). Saline-enhanced bipolar RFA using dual perfused-cooled electrodes increases the dimension of the ablation zone more efficiently than monopolar RFA or single probe bipolar RFA

  12. Cognitive processes and attitudes in bipolar disorder: a study into personality, dysfunctional attitudes and attention bias in patients with bipolar disorder and their relatives.

    Science.gov (United States)

    Jabben, Nienke; Arts, Baer; Jongen, Ellen M M; Smulders, Fren T Y; van Os, Jim; Krabbendam, Lydia

    2012-12-20

    Research in cognitive processes and attitudes in bipolar disorder is scarce and has provided mixed findings, possibly due to differences in current mood state. It is unclear whether alterations in cognitive processes and attitudes are only related to the depressive mood states of bipolar patients or also represent a vulnerability marker for the development of future (depressive) episodes. This was investigated in the current study. Both implicit (attentional bias for emotional words) and explicit (dysfunctional attitudes and personality characteristics) measures of cognitive processes and attitudes were assessed in 77 bipolar patients with varying levels of depressive symptoms (depressed=17, euthymic n=60), their healthy first-degree relatives (n=39) and a healthy control group (n=61). Analyses of variance were used to investigate differences between groups. Mildly depressed patients with bipolar disorder demonstrated an attentional bias away from positive emotional words and showed increased dysfunctional attitudes and higher levels of neuroticism. Euthymic patients were largely comparable to healthy controls and only differed from controls in higher levels of neuroticism. Relatives were similar to controls on all measures, although they significantly differed from bipolar patients in displaying less neuroticism and more extraversion. No firm conclusions regarding causality can be drawn from the associations that were found between cognitive processes and attitudes and the evolution of mood symptoms in bipolar disorder. Alterations in cognitive processes and attitudes in bipolar patients appear to be mostly related to the expression of mood symptomatology rather than to the vulnerability for bipolar disorder. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Analysis of a five year experience of permanent pacemaker implantation at a Nigerian Teaching Hospital: need for a national database

    Science.gov (United States)

    Falase, Bode; Sanusi, Michael; Johnson, Adeyemi; Akinrinlola, Fola; Ajayi, Reina; Oke, David

    2013-01-01

    Introduction Permanent pacemaker implantation is available in Nigeria. There is however no national registry or framework for pacemaker data collection. A pacemaker database has been developed in our institution and the results are analyzed in this study. Methods The study period was between January 2008 and December 2012. Patient data was extracted from a prospectively maintained database which was designed to include the fields of the European pacemaker patient identification code. Results Of the 51 pacemaker implants done, there were 29 males (56.9%) and 22 females (43.1%). Mean age was 68.2±12.7 years. Clinical indications were syncopal attacks in 25 patients (49%), dizzy spells in 15 patients (29.4%), bradycardia with no symptoms in 10 patients (17.7%) and dyspnoea in 2 patients (3.9%). The ECG diagnosis was complete heart block in 27 patients (53%), second degree heart block in 19 patients (37.2%) and sick sinus syndrome with bradycardia in 5 patients (9.8%). Pacemaker modes used were ventricular pacing in 29 patients (56.9%) and dual chamber pacing in 22 patients (43.1%). Files have been closed in 20 patients (39.2%) and 31 patients (60.8%) are still being followed up with median follow up of 26 months, median of 5 visits and 282 pacemaker checks done. Complications seen during follow up were 3 lead displacements (5.9%), 3 pacemaker infections (5.9%), 2 pacemaker pocket erosions (3.9%), and 1 pacemaker related death (2%). There were 5 non-pacemaker related deaths (9.8%). Conclusion Pacemaker data has been maintained for 5 years. We urge other implanting institutions in Nigeria to maintain similar databases and work towards establishment of a national pacemaker registry. PMID:24498465

  14. A new bipolar RRAM selector based on anti-parallel connected diodes for crossbar applications

    International Nuclear Information System (INIS)

    Li, Yingtao; Gong, Qingchun; Li, Rongrong; Jiang, Xinyu

    2014-01-01

    Crossbar arrays are the most promising application of a resistive random access memory (RRAM) device for achieving high density memory. However, cross-talk interference in the crossbar array limits the increase in the integration density. In this paper, the combination of two anti-parallel connected diodes and a bipolar RRAM cell is proposed to suppress the sneak current in a crossbar array with anti-parallel connected diodes as the selector for the bipolar RRAM. By using the anti-parallel connected diodes as a selector, the sneak current can be effectively suppressed and the high density crossbar array of more than 1 Mb can be realized as estimated by the 1/2V read voltage scheme. These results indicate that anti-parallel connected diodes can be used as a bipolar selector and have great potential for high density bipolar RRAM crossbar array applications. (papers)

  15. Bipolar one diode-one resistor integration for high-density resistive memory applications.

    Science.gov (United States)

    Li, Yingtao; Lv, Hangbing; Liu, Qi; Long, Shibing; Wang, Ming; Xie, Hongwei; Zhang, Kangwei; Huo, Zongliang; Liu, Ming

    2013-06-07

    Different from conventional unipolar-type 1D-1R RRAM devices, a bipolar-type 1D-1R memory device concept is proposed and successfully demonstrated by the integration of Ni/TiOx/Ti diode and Pt/HfO2/Cu bipolar RRAM cell to suppress the undesired sneak current in a cross-point array. The bipolar 1D-1R memory device not only achieves self-compliance resistive switching characteristics by the reverse bias current of the Ni/TiOx/Ti diode, but also exhibits excellent bipolar resistive switching characteristics such as uniform switching, satisfactory data retention, and excellent scalability, which give it high potentiality for high-density integrated nonvolatile memory applications.

  16. A review of factors associated with greater likelihood of suicide attempts and suicide deaths in bipolar disorder: Part II of a report of the International Society for Bipolar Disorders Task Force on Suicide in Bipolar Disorder.

    Science.gov (United States)

    Schaffer, Ayal; Isometsä, Erkki T; Azorin, Jean-Michel; Cassidy, Frederick; Goldstein, Tina; Rihmer, Zoltán; Sinyor, Mark; Tondo, Leonardo; Moreno, Doris H; Turecki, Gustavo; Reis, Catherine; Kessing, Lars Vedel; Ha, Kyooseob; Weizman, Abraham; Beautrais, Annette; Chou, Yuan-Hwa; Diazgranados, Nancy; Levitt, Anthony J; Zarate, Carlos A; Yatham, Lakshmi

    2015-11-01

    Many factors influence the likelihood of suicide attempts or deaths in persons with bipolar disorder. One key aim of the International Society for Bipolar Disorders Task Force on Suicide was to summarize the available literature on the presence and magnitude of effect of these factors. A systematic review of studies published from 1 January 1980 to 30 May 2014 identified using keywords 'bipolar disorder' and 'suicide attempts or suicide'. This specific paper examined all reports on factors putatively associated with suicide attempts or suicide deaths in bipolar disorder samples. Factors were subcategorized into: (1) sociodemographics, (2) clinical characteristics of bipolar disorder, (3) comorbidities, and (4) other clinical variables. We identified 141 studies that examined how 20 specific factors influenced the likelihood of suicide attempts or deaths. While the level of evidence and degree of confluence varied across factors, there was at least one study that found an effect for each of the following factors: sex, age, race, marital status, religious affiliation, age of illness onset, duration of illness, bipolar disorder subtype, polarity of first episode, polarity of current/recent episode, predominant polarity, mood episode characteristics, psychosis, psychiatric comorbidity, personality characteristics, sexual dysfunction, first-degree family history of suicide or mood disorders, past suicide attempts, early life trauma, and psychosocial precipitants. There is a wealth of data on factors that influence the likelihood of suicide attempts and suicide deaths in people with bipolar disorder. Given the heterogeneity of study samples and designs, further research is needed to replicate and determine the magnitude of effect of most of these factors. This approach can ultimately lead to enhanced risk stratification for patients with bipolar disorder. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  17. A review of factors associated with greater likelihood of suicide attempts and suicide deaths in bipolar disorder: Part II of a report of the International Society for Bipolar Disorders Task Force on Suicide in Bipolar Disorder

    Science.gov (United States)

    Schaffer, Ayal; Isometsä, Erkki T; Azorin, Jean-Michel; Cassidy, Frederick; Goldstein, Tina; Rihmer, Zoltán; Sinyor, Mark; Tondo, Leonardo; Moreno, Doris H; Turecki, Gustavo; Reis, Catherine; Kessing, Lars Vedel; Ha, Kyooseob; Weizman, Abraham; Beautrais, Annette; Chou, Yuan-Hwa; Diazgranados, Nancy; Levitt, Anthony J; Zarate, Carlos A; Yatham, Lakshmi

    2018-01-01

    Objectives Many factors influence the likelihood of suicide attempts or deaths in persons with bipolar disorder. One key aim of the International Society for Bipolar Disorders Task Force on Suicide was to summarize the available literature on the presence and magnitude of effect of these factors. Methods A systematic review of studies published from 1 January 1980 to 30 May 2014 identified using keywords ‘bipolar disorder’ and ‘suicide attempts or suicide’. This specific paper examined all reports on factors putatively associated with suicide attempts or suicide deaths in bipolar disorder samples. Factors were subcategorized into: (1) sociodemographics, (2) clinical characteristics of bipolar disorder, (3) comorbidities, and (4) other clinical variables. Results We identified 141 studies that examined how 20 specific factors influenced the likelihood of suicide attempts or deaths. While the level of evidence and degree of confluence varied across factors, there was at least one study that found an effect for each of the following factors: sex, age, race, marital status, religious affiliation, age of illness onset, duration of illness, bipolar disorder subtype, polarity of first episode, polarity of current/recent episode, predominant polarity, mood episode characteristics, psychosis, psychiatric comorbidity, personality characteristics, sexual dysfunction, first-degree family history of suicide or mood disorders, past suicide attempts, early life trauma, and psychosocial precipitants. Conclusion There is a wealth of data on factors that influence the likelihood of suicide attempts and suicide deaths in people with bipolar disorder. Given the heterogeneity of study samples and designs, further research is needed to replicate and determine the magnitude of effect of most of these factors. This approach can ultimately lead to enhanced risk stratification for patients with bipolar disorder. PMID:26175498

  18. Sikkerhed af magnetisk resonans-skanning hos patienter med pacemaker og implanterbar defibrillator

    DEFF Research Database (Denmark)

    Al-Sabagh, Kifah Hekmat; Christensen, Britta Ege; Thøgersen, Anna Margrethe

    2010-01-01

    INTRODUCTION: The presence of a cardiac implantable device is ICD considered an absolute contraindication to magnetic resonance imaging (MRI). The purpose of this study was to evaluate the safety of performing MRI in patients with cardiac pacemakers and ICDs that had a compelling clinical need...... for MRI examination. MATERIAL AND METHODS: During a period of nine years we have included 65 patients with cardiac devices (60 pacemakers and five ICDs) who underwent a total of 73 MRI examinations at 1.5 T. All pacemakers were reprogrammed before MRI to asynchronous mode to avoid MRI-induced inhibition...... safely in 63 patients. Inhibition of pacemaker output was observed in one patient and induction of ventricular fibrillation was observed in another with ICD. A significant increase in PCT was rare and only detected in 1% of all electrodes. CONCLUSION: MRI can be performed safely in patients...

  19. Magnetic Resonance Imaging in a Patient with a Dual Chamber Pacemaker

    Directory of Open Access Journals (Sweden)

    Lynne Martina Millar

    2010-01-01

    Full Text Available Having a pacemaker has been seen an absolute contraindication to having an MRI scan. This has become increasingly difficult in clinical practice as insertion of pacemakers and implantable cardiac defibrillators is at an all time high. Here we outline a case where a 71-year-old male patient with a permanent pacemaker needed to have an MRI scan to ascertain the aetiology of his condition and help guide further management. Given this clinical dilemma, an emergency clinical ethics consultation was arranged. As a result the patient underwent an MRI scan safely under controlled conditions with a consultant cardiologist and radiologist present. The results of the MRI scan were then able to tailor further treatment. This case highlights that in certain conditions an MRI can be performed in patients with permanent pacemakers and outlines the role of clinical ethics committees in complex medical decision making.

  20. The influence of ionizing radiation on the probability of failure of long-term pacemakers

    International Nuclear Information System (INIS)

    Eger, H.; Hesse, W.; Otte, K.B.; Rauh, G.; Salewski, D.; Stopp, G.

    1982-01-01

    The functional disturbances observed during the exposure of cardiac pacemakers with a CMOS switching circle U 115 are described qualitatively for different types of radiation. Based on the maximum sensitivity of the U 115 within the X-ray range, the correlation for this range between dose of exposure and parameter changes is established. As is demonstrated such changes is established. As is demonstrated such changes are not clinically relevant as long as the dose of 5,16 x 10 -2 C/kg is not exceeded. Proceeding from the accumulated dose to which the U 115 is exposed during various diagnostic radiographic procedures it is shown that such procedures do not result in functional disturbances of the pacemaker. Recommendations are given for radiotherapeutic measures as to pacemaker patients, which should be realized in close co-operation between the pacemaker centre concerned and an authorized hospital. (author)

  1. Influence of ionizing radiation on the probability of failure of long-term pacemakers

    Energy Technology Data Exchange (ETDEWEB)

    Eger, H.; Hesse, W.; Otte, K.B.; Rauh, G.; Salewski, D.; Stopp, G. (Zentralklinik fuer Herz- und Lungenkrankheiten, Bad Berka (German Democratic Republic); VEB Transformatoren- und Roentgenwerk ' Hermann Matern' Dresden (German Democratic Republic); Martin-Luther-Universitaet Halle-Wittenberg, Halle (German Democratic Republic). Radiologische Klinik; Staatliches Amt fuer Atomsicherheit und Strahlenschutz, Berlin (German Democratic Republic))

    1982-11-01

    The functional disturbances observed during the exposure of cardiac pacemakers with a CMOS switching circle U 115 are described qualitatively for different types of radiation. Based on the maximum sensitivity of the U 115 within the X-ray range, the correlation for this range between dose of exposure and parameter changes is established. As is demonstrated such changes is established. As is demonstrated such changes are not clinically relevant as long as the dose of 5,16 x 10/sup -2/ C/kg is not exceeded. Proceeding from the accumulated dose to which the U 115 is exposed during various diagnostic radiographic procedures it is shown that such procedures do not result in functional disturbances of the pacemaker. Recommendations are given for radiotherapeutic measures as to pacemaker patients, which should be realized in close co-operation between the pacemaker centre concerned and an authorized hospital.

  2. Monitoring the radiation dose to a multiprogrammable pacemaker during radical radiation therapy: A case report

    International Nuclear Information System (INIS)

    Muller-Runkel, R.; Orsolini, G.; Kalokhe, U.P.

    1990-01-01

    Multiprogrammable pacemakers, using complimentary metaloxide semiconductor (CMOS) circuitry, may fail during radiation therapy. We report about a patient who received 6,400 cGy for unresectable carcinoma of the left lung. In supine treatment position, arms raised above the head, the pacemaker was outside the treated area by a margin of at least 1 cm, shielded by cerrobend blocking mounted on a tray. From thermoluminescent dosimeter (TLD) measurements, we estimate that the pacemaker received 620 cGy in scatter doses. Its function was monitored before, during, and after completion of radiation therapy. The pacemaker was functioning normally until the patient's death 5 months after completion of treatment. The relevant electrocardiograms (ECGs) are presented

  3. Machines in our hearts: the cardiac pacemaker, the implantable defibrillator, and American health care

    National Research Council Canada - National Science Library

    Jeffrey, Kirk

    2001-01-01

    ... A Device Reliability, Qualification Tests, and Improvements 291 APPENDIX B Number of Implantations 294 APPENDIX C ICHD Pacemaker Identification Code 296 Abbreviations 297 Notes 299 Bibliographical N...

  4. Magnetic resonance imaging in patients with cardiac pacemakers: In vitro-and vivo-evaluation at 0.5 Tesla

    International Nuclear Information System (INIS)

    Sommer, T.; Block, W.; Schild, H.; Schimpf, R.; Smekal, A. v.; Wolke, S.; Gieseke, J.; Schneider, C.; Funke, H.D.

    1998-01-01

    Purpose: MRI is currently regarded as absolutely contraindicated in patients with implanted cardiac pacemakers. In this prospective study safety and feasibility of MRI in patients with new generation pacemakers (PM) was evaluated in vitro and in vivo. Results: In the static magnetic field all PM switched to the asynchronous mode due to activation of the Reed switch, resulting in continuous pacing at a fixed rate. In three PM models in vitro, however, after activation of the Reed switch, there was a software-induced switch back to the demand mode. In these PM inhibition and triggering were observed after starting the MRI scan due to influence of the pulsed magnetic fields. PM program changes, damage of PM components, dislocation/torque of the PM and rapid pacing of the PM were observed neither in vitro nor in vivo. Atrial and ventricular stimulation thresholds remained unchanged. Conclusion: MRI at 0.5 Tesla should not be regarded as absolutely contraindicated in patients with implanted new generation PM. However, knowledge of the behaviour of the specific PM model in static and pulsed magnetic fields is required, if necessary also changes of the PM program prior of the MRI exam, continuous ECG monitoring and cardiological stand-by. (orig.) [de

  5. Radiation therapy in patients with cardiac pacemakers or implantable cardioverter defibrillators. Interdisciplinary safety recommendations; Strahlentherapie bei Patienten mit Herzschrittmachern oder implantierbaren Kardioverter-Defibrillatoren. Interdisziplinaere Sicherheitsempfehlungen

    Energy Technology Data Exchange (ETDEWEB)

    Dorenkamp, M.; Haverkmap, W.; Roser, M. [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum (Germany). Medizinische Klinik mit Schwerpunkt Kardiologie; Stromberger, C.; Wust, P. [Charite Universitaetsmedizin Berlin (Germany). Klinik fuer Radioonkologie und Strahlentherapie; Heymann, C. von [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum (Germany). Klinik fuer Anaesthesiologie mit Schwerpunkt operative Intensivmedizin

    2013-01-15

    Background: With increasing numbers of implanted pacemakers and implantable cardioverter defibrillators (ICD) and a rising incidence of malignant tumors, there is a growing probability of radiation-mediated device dysfunction. The only guidelines for the management of patients with cardiac pacemakers in the case of radiation therapy were published in 1994 and have not been updated since then. Based on the current evidence and modern device technology, the present paper aims to develop contemporary and interdisciplinary safety recommendations for the minimization of patient risk. Methods and results: A systematic literature research was carried out including the most relevant medical electronic databases. The search yielded 147 articles published between 1994 and 2012 of which 45 met the selection criteria and of these studies 34 presented primary data (9 in vitro and 25 in vivo studies). The impact of ionizing radiation varied significantly between implanted devices and ranged from no functional changes to complete loss of function. Important device dysfunctions included changes in sensing capability, altered pacing pulses or rate, changed or disabled tachyarrhythmia ICD therapies, early battery depletion and loss of telemetry. Modern pacemakers and ICDs are more sensitive to radiation than older models. Potentially life-threatening complications were observed after exposure of the pulse generator to comparatively low radiation doses (0.11 Gy). Conclusions: Practical recommendations for patient management and safety are presented that can be readily adopted by any institution carrying out radiation therapy. (orig.)

  6. SU-E-I-42: Normalized Embryo/fetus Doses for Fluoroscopically Guided Pacemaker Implantation Procedures Calculated Using a Monte Carlo Technique

    Energy Technology Data Exchange (ETDEWEB)

    Damilakis, J; Stratakis, J; Solomou, G [University of Crete, Heraklion (Greece)

    2014-06-01

    Purpose: It is well known that pacemaker implantation is sometimes needed in pregnant patients with symptomatic bradycardia. To our knowledge, there is no reported experience regarding radiation doses to the unborn child resulting from fluoroscopy during pacemaker implantation. The purpose of the current study was to develop a method for estimating embryo/fetus dose from fluoroscopically guided pacemaker implantation procedures performed on pregnant patients during all trimesters of gestation. Methods: The Monte Carlo N-Particle (MCNP) radiation transport code was employed in this study. Three mathematical anthropomorphic phantoms representing the average pregnant patient at the first, second and third trimesters of gestation were generated using Bodybuilder software (White Rock science, White Rock, NM). The normalized embryo/fetus dose from the posteroanterior (PA), the 30° left-anterior oblique (LAO) and the 30° right-anterior oblique (RAO) projections were calculated for a wide range of kVp (50–120 kVp) and total filtration values (2.5–9.0 mm Al). Results: The results consist of radiation doses normalized to a) entrance skin dose (ESD) and b) dose area product (DAP) so that the dose to the unborn child from any fluoroscopic technique and x-ray device used can be calculated. ESD normalized doses ranged from 0.008 (PA, first trimester) to 2.519 μGy/mGy (RAO, third trimester). DAP normalized doses ranged from 0.051 (PA, first trimester) to 12.852 μGy/Gycm2 (RAO, third trimester). Conclusion: Embryo/fetus doses from fluoroscopically guided pacemaker implantation procedures performed on pregnant patients during all stages of gestation can be estimated using the method developed in this study. This study was supported by the Greek Ministry of Education and Religious Affairs, General Secretariat for Research and Technology, Operational Program ‘Education and Lifelong Learning’, ARISTIA (Research project: CONCERT)

  7. SU-E-I-42: Normalized Embryo/fetus Doses for Fluoroscopically Guided Pacemaker Implantation Procedures Calculated Using a Monte Carlo Technique

    International Nuclear Information System (INIS)

    Damilakis, J; Stratakis, J; Solomou, G

    2014-01-01

    Purpose: It is well known that pacemaker implantation is sometimes needed in pregnant patients with symptomatic bradycardia. To our knowledge, there is no reported experience regarding radiation doses to the unborn child resulting from fluoroscopy during pacemaker implantation. The purpose of the current study was to develop a method for estimating embryo/fetus dose from fluoroscopically guided pacemaker implantation procedures performed on pregnant patients during all trimesters of gestation. Methods: The Monte Carlo N-Particle (MCNP) radiation transport code was employed in this study. Three mathematical anthropomorphic phantoms representing the average pregnant patient at the first, second and third trimesters of gestation were generated using Bodybuilder software (White Rock science, White Rock, NM). The normalized embryo/fetus dose from the posteroanterior (PA), the 30° left-anterior oblique (LAO) and the 30° right-anterior oblique (RAO) projections were calculated for a wide range of kVp (50–120 kVp) and total filtration values (2.5–9.0 mm Al). Results: The results consist of radiation doses normalized to a) entrance skin dose (ESD) and b) dose area product (DAP) so that the dose to the unborn child from any fluoroscopic technique and x-ray device used can be calculated. ESD normalized doses ranged from 0.008 (PA, first trimester) to 2.519 μGy/mGy (RAO, third trimester). DAP normalized doses ranged from 0.051 (PA, first trimester) to 12.852 μGy/Gycm2 (RAO, third trimester). Conclusion: Embryo/fetus doses from fluoroscopically guided pacemaker implantation procedures performed on pregnant patients during all stages of gestation can be estimated using the method developed in this study. This study was supported by the Greek Ministry of Education and Religious Affairs, General Secretariat for Research and Technology, Operational Program ‘Education and Lifelong Learning’, ARISTIA (Research project: CONCERT)

  8. Structural and functional changes in the somatosensory cortex in euthymic females with bipolar disorder.

    Science.gov (United States)

    Minuzzi, Luciano; Syan, Sabrina K; Smith, Mara; Hall, Alexander; Hall, Geoffrey Bc; Frey, Benicio N

    2017-12-01

    Current evidence from neuroimaging data suggests possible dysfunction of the fronto-striatal-limbic circuits in individuals with bipolar disorder. Somatosensory cortical function has been implicated in emotional recognition, risk-taking and affective responses through sensory modalities. This study investigates anatomy and function of the somatosensory cortex in euthymic bipolar women. In total, 68 right-handed euthymic women (bipolar disorder = 32 and healthy controls = 36) between 16 and 45 years of age underwent high-resolution anatomical and functional magnetic resonance imaging during the mid-follicular menstrual phase. The somatosensory cortex was used as a seed region for resting-state functional connectivity analysis. Voxel-based morphometry was used to evaluate somatosensory cortical gray matter volume between groups. We found increased resting-state functional connectivity between the somatosensory cortex and insular cortex, inferior prefrontal gyrus and frontal orbital cortex in euthymic bipolar disorder subjects compared to healthy controls. Voxel-based morphometry analysis showed decreased gray matter in the left somatosensory cortex in the bipolar disorder group. Whole-brain voxel-based morphometry analysis controlled by age did not reveal any additional significant difference between groups. This study is the first to date to evaluate anatomy and function of the somatosensory cortex in a well-characterized sample of euthymic bipolar disorder females. Anatomical and functional changes in the somatosensory cortex in this population might contribute to the pathophysiology of bipolar disorder.

  9. Access to Pharmacotherapy Amongst Women with Bipolar Disorder during Pregnancy: a Preliminary Study.

    Science.gov (United States)

    Byatt, Nancy; Cox, Lucille; Moore Simas, Tiffany A; Biebel, Kathleen; Sankaran, Padma; Swartz, Holly A; Weinreb, Linda

    2018-03-01

    Bipolar disorder among pregnant women has deleterious effects on birth and child outcomes and is currently under-detected, not addressed effectively, or exacerbated through inappropriate treatment. The goal of this study was to identify perspectives of pregnant and postpartum women with bipolar disorder on barriers and facilitators to psychiatric treatment during pregnancy. In-depth interviews were conducted with pregnant and postpartum women who scored ≥ 10 on the Edinburgh Postnatal Depression Scale and met DSM-IV criteria for bipolar disorder I, II or not otherwise specified using the Mini International Neuropsychiatric Interview version 5.0. Interviews were transcribed, and resulting data were analyzed using a grounded theory approach to identify barriers and facilitators to bipolar disorder treatment access in pregnancy. Participant identified barriers included perception that psychiatric providers lack training and experience in the treatment of psychiatric illness during pregnancy, are reluctant to treat bipolar disorder among pregnant women, and believe that pharmacotherapy is not needed for psychiatric illness during pregnancy. Facilitators included participants' perception that providers' acknowledge risks associated with untreated or undertreated psychiatric illness during pregnancy and provide psycho-education about the risks, benefits and alternatives to pharmacotherapy. Psychiatric providers are critically important to the treatment of bipolar disorder and need knowledge and skills necessary to provide care during the perinatal period. Advancing psychiatric providers' knowledge/skills may improve access to pharmacotherapy for pregnant women with bipolar disorder.

  10. Women with bipolar disorder and pregnancy: factors influencing their decision-making.

    Science.gov (United States)

    Dolman, Clare; Jones, Ian R; Howard, Louise M

    2016-09-01

    Women with bipolar disorder are at increased risk of having a severe episode of illness associated with childbirth. To explore the factors that influence the decision-making of women with bipolar disorder regarding pregnancy and childbirth. Qualitative study with a purposive sample of women with bipolar disorder considering pregnancy, or currently or previously pregnant, supplemented by data from an online forum. Data were analysed using thematic analysis. Twenty-one women with bipolar disorder from an NHS organisation were interviewed, and data were used from 50 women's comments via the online forum of the UK's national bipolar charity. The centrality of motherhood, social and economic contextual factors, stigma and fear were major themes. Within these themes, new findings included women considering an elective Caesarian section in an attempt to avoid the deleterious effects of a long labour and loss of sleep, or trying to avoid the risks of pregnancy altogether by means of adoption or surrogacy. This study highlights the information needs of women with bipolar disorder, both pre-conception and when childbearing, and the need for improved training for all health professionals working with women with bipolar disorder of childbearing age to reduce stigmatising attitudes and increase knowledge of the evidence base on treatment in the perinatal period. None. © The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.

  11. Frequency of pacemaker malfunction associated with monopolar electrosurgery during pulse generator replacement or upgrade surgery.

    Science.gov (United States)

    Lin, Yun; Melby, Daniel P; Krishnan, Balaji; Adabag, Selcuk; Tholakanahalli, Venkatakrishna; Li, Jian-Ming

    2017-08-01

    The aim of this study is to investigate the frequency of electrosurgery-related pacemaker malfunction. A retrospective study was conducted to investigate electrosurgery-related pacemaker malfunction in consecutive patients undergoing pulse generator (PG) replacement or upgrade from two large hospitals in Minneapolis, MN between January 2011 and January 2014. The occurrence of this pacemaker malfunction was then studied by using MAUDE database for all four major device vendors. A total of 1398 consecutive patients from 2 large tertiary referral centers in Minneapolis, MN undergoing PG replacement or upgrade surgery were retrospectively studied. Four patients (0.3% of all patients), all with pacemakers from St Jude Medical (2.8%, 4 of 142) had output failure or inappropriately low pacing rate below 30 bpm during electrosurgery, despite being programmed in an asynchronous mode. During the same period, 1174 cases of pacemaker malfunctions were reported on the same models in MAUDE database, 37 of which (3.2%) were electrosurgery-related. Twenty-four cases (65%) had output failure or inappropriate low pacing rate. The distribution of adverse events was loss of pacing (59.5%), reversion to backup pacing (32.4%), inappropriate low pacing rate (5.4%), and ventricular fibrillation (2.7%). The majority of these (78.5%) occurred during PG replacement at ERI or upgrade surgery. No electrosurgery-related malfunction was found in MAUDE database on 862 pacemaker malfunction cases during the same period from other vendors. Electrosurgery during PG replacement or upgrade surgery can trigger output failure or inappropriate low pacing rate in certain models of modern pacemakers. Cautions should be taken for pacemaker-dependent patients.

  12. A Fully Implantable Pacemaker for the Mouse: From Battery to Wireless Power

    Science.gov (United States)

    Zellmer, Erik R.; Weinheimer, Carla J.; MacEwan, Matthew R.; Cui, Sophia X.; Nerbonne, Jeanne M.; Efimov, Igor R.

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice. PMID:24194832

  13. Is pacemaker therapy the right key to patients with vasovagal syncope?

    Science.gov (United States)

    Radovanović, Nikola N; Kirćanski, Bratislav; Raspopović, Srdjan; Pavlović, Siniša U; Jovanović, Velibor; Milašinović, Goran

    2016-01-01

    Vasovagal syncope is the most common type of reflex syncope. Efficacy of cardiac pacing in this indication has not been the subject of many studies and pacemaker therapy in patients with vasovagal syncope is still controversial. This study aimed to assess the efficacy and safety of pacing therapy in treatment of patients with vasovagal syncope, to determine contribution of new therapeutic models in increasing its success, and to identify risk factors associated with a higher rate of symptoms after pacemaker implantation. A retrospective study included 30 patients with pacemaker implanted due to vasovagal syncope in the Pacemaker Center, Clinical Center of Serbia, between November 2003 and June 2014. Head-up tilt test was performed to diagnose vasovagal syncope. Patients with cardioinhibitory and mixed type of disease were enrolled in the study. Mean age was 48.1 ± 11.1 years and 18 (60%) patients were men. Mean follow-up period was 5.9 ± 3.0 years. Primarily, implantable loop recorder was implanted in 10 (33.3%) patients. Twenty (66.7%) patients presented cardioinhibitory and 10 (33.3%) mixed type of vasovagal syncope. After pacemaker implantation, 11 (36.7%) patients had syncope. In multiple logistic regression analysis we showed that syncope is statistically more likely to occur after pacemaker implantation in patients with mixed type of vasovagal syncope (p = 0.018). There were two (6.7%) perioperative surgical complications. Pacemaker therapy is a safe treatment for patients with vasovagal syncope, whose efficacy can be improved by strict selection of patients. We showed that symptoms occur statistically more often in patients with mixed type of disease after pacemaker implantation.

  14. The oral cavity is not a primary source for implantable pacemaker or cardioverter defibrillator infections

    Science.gov (United States)

    2013-01-01

    Background To test the hypothesis that the oral cavity is a potential source for implantable pacemaker and cardioverter defibrillators infections, the bacterial diversity on explanted rhythm heart management devices was investigated and compared to the oral microbiome. Methods A metagenomic approach was used to analyze the bacterial diversity on the surfaces of non-infected and infected pacemakers. The DNA from surfaces swaps of 24 non-infected and 23 infected pacemaker were isolated and subjected to bacterial-specific DNA amplification, single strand conformation polymorphism- (SSCP) and sequencing analysis. Species-specific primer sets were used to analyze for any correlation between bacterial diversity on pacemakers and in the oral cavity. Results DNA of bacterial origin was detected in 21 cases on infected pacemakers and assigned to the bacterial phylotypes Staphylococcus epidermidis, Propionibacterium acnes, Staphylococcus aureus, Staphylococcus schleiferi and Stapyhlococcus. In 17 cases bacterial DNA was found on pacemakers with no clinical signs of infections. On the basis of the obtained sequence data, the phylotypes Propionibacterium acnes, Staphylococcus and an uncultured bacterium were identified. Propionibacterium acnes and Staphylococcus epidermidis were the only bacteria detected in pacemeaker (n = 25) and oral samples (n = 11). Conclusions The frequency of the coincidental detection of bacteria on infected devices and in the oral cavity is low and the detected bacteria are highly abundant colonizers of non-oral human niches. The transmission of oral bacteria to the lead or device of implantable pacemaker or cardioverter defibrillators is unlikely relevant for the pathogenesis of pacemaker or cardioverter defibrillators infections. PMID:23575037

  15. A fully implantable pacemaker for the mouse: from battery to wireless power.

    Science.gov (United States)

    Laughner, Jacob I; Marrus, Scott B; Zellmer, Erik R; Weinheimer, Carla J; MacEwan, Matthew R; Cui, Sophia X; Nerbonne, Jeanne M; Efimov, Igor R

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice.

  16. Interference of apex locator, pulp tester and diathermy on pacemaker function

    OpenAIRE

    Narayanan Sriman; V Prabhakar; J S Bhuvaneswaran; N Subha

    2015-01-01

    Aim: The purpose of this study was to evaluate the effects of three electronic apex locators (EAL), electric pulp tester (EPT) and diathermy on pacemaker function in vitro. Materials and Methods: Three EALs: Root ZX (J. Morita Co., Tustin, CA, U.S.A.), Propex (Dentsply), Mini Apex locator (SybronEndo, Anaheim, CA, USA), EPT (Parkell pulp vitality tester Farmingdale, NY, USA) and Diathermy (Neomed 250 B) were tested for any interference with one pacemaker (A medtronic kappa KVDD901-serial ...

  17. A fully implantable pacemaker for the mouse: from battery to wireless power.

    Directory of Open Access Journals (Sweden)

    Jacob I Laughner

    Full Text Available Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24 were implanted with endocardial, battery-powered devices (n = 14 and epicardial, wireless-powered devices (n = 10. Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1% mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10% mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice.

  18. Unrecognized bipolar disorder in patients with a diagnosis of unipolar depression%诊断为单相抑郁症者中未识别的双相障碍

    Institute of Scientific and Technical Information of China (English)

    David L.DUNNER

    2011-01-01

    @@ The diagnosis of bipolar rather than unipolar depression is currently a clinicaI diagnosis which cannot be validated by specific biological measures,such as laboratory tests.Certainly the characteristics of bipolar depression frequently differ from unipolar major depression in that patients with bipolar depression generally have an earlier age of onset and more frequent episodes than individuals with unipolar major depression[1]Some,but not all,studies support an increase in suicidal behaviors among bipolar as compared with unipolar major depression[2],and"atypical features"such as hypersomnia and hyperphagia also may be found more frequently among individuals with bipolar depression.Furthermore family histories of subjects with bipolar disorders more frequently reveal relatives with bipolar disorder.In contrast,relatives of patients with unipolar depression's family history generally reflects major depression but not bipolar disorder[3].

  19. Social cognition and functional capacity in bipolar disorder and schizophrenia.

    Science.gov (United States)

    Thaler, Nicholas S; Sutton, Griffin P; Allen, Daniel N

    2014-12-15

    Social cognition is a functionally relevant predictor of capacity in schizophrenia (SZ), though research concerning its value for bipolar disorder (BD) is limited. The current investigation examined the relationship between two social cognitive factors and functional capacity in bipolar disorder. This study included 48 individuals with bipolar disorder (24 with psychotic features) and 30 patients with schizophrenia. Multiple regression controlling for estimated IQ scores was used to assess the predictive value of social cognitive factors on the UCSD Performance-Based Functional Skills Assessment (UPSA). Results found that for the bipolar with psychosis and schizophrenia groups, the social/emotion processing factor predicted the UPSA. The theory of mind factor only predicted the UPSA for the schizophrenia group.. Findings support the clinical utility of evaluating emotion processing in individuals with a history of psychosis. For BD, theory of mind may be better explained by a generalized cognitive deficit. In contrast, social/emotion processing may be linked to distinct neurobiological processes associated with psychosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. [Comorbidity of eating disorders and bipolar affective disorders].

    Science.gov (United States)

    Kamińska, Katarzyna; Rybakowski, Filip

    2006-01-01

    Eating disorders--anorexia nervosa, bulimia nervosa and eating disorders not otherwise specified (EDNOS) occur usually in young females. The significant pathogenic differences between patients who only restrict food, and patients with binge eating and compensatory behaviours, such as vomiting and purging were described. The prevalence of bipolar affective disorders--especially bipolar II and bipolar spectrum disorders (BS) may reach 5% in the general population. About half of the depressive episodes are associated with a "mild" bipolar disorder, and such a diagnosis is suggested by impulsivity and mood-instability. Previously, majority of research on the comorbidity between eating and affective disorders focused on depressive symptomatology, however difficulties in the reliable assessment of hypomania may obfuscate the estimation of the co-occurrence of eating disorders with BS. Epidemiological studies suggest the association between BS and eating disorders with binge episodes (bulimia nervosa, anorexia- bulimic type and EDNOS with binge episodes). Co-occurrence of such disorders with depressive symptoms probably suggests the diagnosis of BS, not recurrent depression. Bulimic behaviours, impulsivity and affective disorders might be related to the impairment of the serotonergic neurotransmission, which may result from the genetic vulnerability and early life trauma. Currently, the first-line pharmacological treatment of co-occurring eating disorders with binge episodes and BS are selective serotonin reuptake inhibitors. However in some cases, the use of mood-stabilising agents as monotherapy or in combination with serotonergic drugs may be helpful.

  1. [BIPOLAR DISORDER AS A MULTI-SYSTEM ILLNESS].

    Science.gov (United States)

    Fenchel, Daphna; Levkovitz, Yechiel; Kotler, Moshe

    2017-12-01

    Bipolar disorder is a chronic condition, characterized by high distress in patients and high suicide rates (30%). Most patients suffer from medical and other psychiatric comorbidities, which worsen the psychiatric symptoms and decrease the likelihood of remission. More than 70% of bipolar patients have cardio-metabolic symptoms, with higher rates compared to other psychiatric disorders. Cardiovascular disease is the major cause of high mortality rates in these patients, with 1.5-2 fold increased risk of mortality, compared to the general population without psychiatric symptoms. The rates of cardiovascular risk factors and their resulting increased mortality rates are similar to those found in schizophrenia. In addition to cardio-metabolic conditions, 50% of patients with bipolar disorder suffer from other medical symptoms, which are also associated with worse outcomes. Therefore, the current perspective is that bipolar disorder is not only a psychiatric disorder, but rather a multi-system illness, affecting the entire body. The optimal treatment for these patients should include diagnosis, monitoring and treatment of both psychiatric and physical symptoms, which would improve their prognosis.

  2. Technical Note: Interleaved Bipolar Acquisition and Low-rank Reconstruction for Water-Fat Separation in MRI.

    Science.gov (United States)

    Cho, JaeJin; Park, HyunWook

    2018-05-17

    To acquire interleaved bipolar data and reconstruct the full data using low-rank property for water fat separation. Bipolar acquisition suffers from issues related to gradient switching, the opposite gradient polarities, and other system imperfections, which prevent accurate water-fat separation. In this study, an interleaved bipolar acquisition scheme and a low-rank reconstruction method were proposed to reduce issues from the bipolar gradients while achieving a short imaging time. The proposed interleaved bipolar acquisition scheme collects echo-time signals from both gradient polarities; however, the sequence increases the imaging time. To reduce the imaging time, the signals were subsampled at every dimension of k-space. The low-rank property of the bipolar acquisition was defined and exploited to estimate the full data from the acquired subsampled data. To eliminate the bipolar issues, in the proposed method, the water-fat separation was performed separately for each gradient polarity, and the results for the positive and negative gradient polarities were combined after the water-fat separation. A phantom study and in-vivo experiments were conducted on a 3T Siemens Verio system. The results for the proposed method were compared with the results of the fully sampled interleaved bipolar acquisition and Soliman's method, which was the previous water-fat separation approach for reducing the issues of bipolar gradients and accelerating the interleaved bipolar acquisition. The proposed method provided accurate water and fat images without the issues of bipolar gradients and demonstrated a better performance compared with the results of the previous methods. The water-fat separation using the bipolar acquisition has several benefits including a short echo-spacing time. However, it suffers from bipolar-gradient issues such as strong gradient switching, system imperfection, and eddy current effects. This study demonstrated that accurate water-fat separated images can

  3. Multiple photoreceptor systems control the swim pacemaker activity in box jellyfish

    DEFF Research Database (Denmark)

    Garm, Anders Lydik; Mori, S.

    2009-01-01

    Like all other cnidarian medusae, box jellyfish propel themselves through the water by contracting their bell-shaped body in discrete swim pulses. These pulses are controlled by a swim pacemaker system situated in their sensory structures, the rhopalia. Each medusa has four rhopalia each with a s......Like all other cnidarian medusae, box jellyfish propel themselves through the water by contracting their bell-shaped body in discrete swim pulses. These pulses are controlled by a swim pacemaker system situated in their sensory structures, the rhopalia. Each medusa has four rhopalia each...... with a similar set of six eyes of four morphologically different types. We have examined how each of the four eye types influences the swim pacemaker. Multiple photoreceptor systems, three of the four eye types, plus the rhopalial neuropil, affect the swim pacemaker. The lower lens eye inhibits the pacemaker...... when stimulated and provokes a strong increase in the pacemaker frequency upon light-off. The upper lens eye, the pit eyes and the rhopalial neuropil all have close to the opposite effect. When these responses are compared with all-eye stimulations it is seen that some advanced integration must take...

  4. Development of pacemaker properties and rhythmogenic mechanisms in the mouse embryonic respiratory network

    Science.gov (United States)

    Chevalier, Marc; Toporikova, Natalia; Simmers, John; Thoby-Brisson, Muriel

    2016-01-01

    Breathing is a vital rhythmic behavior generated by hindbrain neuronal circuitry, including the preBötzinger complex network (preBötC) that controls inspiration. The emergence of preBötC network activity during prenatal development has been described, but little is known regarding inspiratory neurons expressing pacemaker properties at embryonic stages. Here, we combined calcium imaging and electrophysiological recordings in mouse embryo brainstem slices together with computational modeling to reveal the existence of heterogeneous pacemaker oscillatory properties relying on distinct combinations of burst-generating INaP and ICAN conductances. The respective proportion of the different inspiratory pacemaker subtypes changes during prenatal development. Concomitantly, network rhythmogenesis switches from a purely INaP/ICAN-dependent mechanism at E16.5 to a combined pacemaker/network-driven process at E18.5. Our results provide the first description of pacemaker bursting properties in embryonic preBötC neurons and indicate that network rhythmogenesis undergoes important changes during prenatal development through alterations in both circuit properties and the biophysical characteristics of pacemaker neurons. DOI: http://dx.doi.org/10.7554/eLife.16125.001 PMID:27434668

  5. Biological pacemaker created by minimally invasive somatic reprogramming in pigs with complete heart block

    Science.gov (United States)

    Hu, Yu-Feng; Dawkins, James Frederick; Cho, Hee Cheol; Marbán, Eduardo; Cingolani, Eugenio

    2016-01-01

    Somatic reprogramming by reexpression of the embryonic transcription factor T-box 18 (TBX18) converts cardiomyocytes into pacemaker cells. We hypothesized that this could be a viable therapeutic avenue for pacemaker-dependent patients afflicted with device-related complications, and therefore tested whether adenoviral TBX18 gene transfer could create biological pacemaker activity in vivo in a large-animal model of complete heart block. Biological pacemaker activity, originating from the intramyocardial injection site, was evident in TBX18-transduced animals starting at day 2 and persisted for the duration of the study (14 days) with minimal backup electronic pacemaker use. Relative to controls transduced with a reporter gene, TBX18-transduced animals exhibited enhanced autonomic responses and physiologically superior chronotropic support of physical activity. Induced sinoatrial node cells could be identified by their distinctive morphology at the site of injection in TBX18-transduced animals, but not in controls. No local or systemic safety concerns arose. Thus, minimally invasive TBX18 gene transfer creates physiologically relevant pacemaker activity in complete heart block, providing evidence for therapeutic somatic reprogramming in a clinically relevant disease model. PMID:25031269

  6. Study on ionizing radiation effects of bipolar transistor with BPSG films

    International Nuclear Information System (INIS)

    Lu Man; Zhang Xiaoling; Xie Xuesong; Sun Jiangchao; Wang Pengpeng; Lu Changzhi; Zhang Yanxiu

    2013-01-01

    Background: Because of the damage induced by ionizing radiation, bipolar transistors in integrated voltage regulator could induce the current gain degradation and increase leakage current. This will bring serious problems to electronic system. Purpose: In order to ensure the reliability of the device work in the radiation environments, the device irradiation reinforcement technology is used. Methods: The characteristics of 60 Co γ irradiation and annealing at different temperatures in bipolar transistors and voltage regulators (JW117) with different passive films for SiO 2 +BPSG+SiO 2 and SiO 2 +SiN have been investigated. Results: The devices with BPSG film enhanced radiation tolerance significantly. Because BPSG films have better absorption for Na + in SiO 2 layer, the surface recombination rate of base region in a bipolar transistor and the excess base current have been reduced. It may be the main reason for BJT with BPSG film having a good radiation hardness. And annealing experiments at different temperatures after irradiation ensure the reliability of the devices with BPSG films. Conclusions: A method of improving the ionizing irradiation hardness of bipolar transistors is proposed. As well as the linear integrated circuits which containing bipolar transistors, an experimental basis for the anti-ionizing radiation effects of bipolar transistors is provided. (authors)

  7. Bipolar polygenic loading and bipolar spectrum features in major depressive disorder

    NARCIS (Netherlands)

    Wiste, Anna; Robinson, Elise B.; Milaneschi, Yuri; Meier, Sandra; Ripke, Stephan; Clements, Caitlin C.; Fitzmaurice, Garrett M.; Rietschel, Marcella; Penninx, Brenda W.; Smoller, Jordan W.; Perlis, Roy H.

    Objectives Family and genetic studies indicate overlapping liability for major depressive disorder and bipolar disorder. The purpose of the present study was to determine whether this shared genetic liability influences clinical presentation. Methods A polygenic risk score for bipolar disorder,

  8. Lateral n-p-n bipolar transistors by ion implantation into semi-insulating GaAs

    International Nuclear Information System (INIS)

    Canfield, P.; Forbes, L.

    1988-01-01

    GaAs bipolar transistors have not seen the major development effort that GaAs MESFETs have due primarily to the short minority carrier lifetimes in GaAs. The short minority carrier lifetimes require that the base region be very thin which, if done by implantation, requires that the doping be high to obtain a well defined base profile. These requirements are very difficult to achieve in GaAs and typically, if high current gain and high speed are desired for a bipolar technology, then heterostructure bipolars are the appropriate technology, although the cost of heterostructure devices will be prohibitive for some time to come. For applications requiring low current gain, more modest fabrication rules can be followed. Lateral bipolars are particularly attractive since they would be easier to fabricate than a planar bipolar or a heterojunction bipolar. Lateral bipolars do not require steps or deep contacts to make contact with the subcollector or highly doped very thin epilayers for the base region and they can draw upon the semi-insulating properties of the GaAs substrates for device isolation. Bipolar transistors are described and shown to work successfully. (author)

  9. Use of an active fixation lead and a subpectoral pacemaker pocket may not avoid Twiddler′s syndrome

    Directory of Open Access Journals (Sweden)

    Floris E A Udink ten Cate

    2012-01-01

    Full Text Available Manipulation of a pacemaker with consequent malfunction of the device has been called Twiddler′s syndrome. Use of active-fixation leads and subpectoral pacemaker pockets has been considered to help in avoiding this problem. We describe a child in whom twiddling was not prevented despite implantation of a lumenless atrial lead and insertion of the pacemaker generator in a subpectoral pocket.

  10. Dosimetric perturbations due to an implanted cardiac pacemaker in MammoSite{sup Registered-Sign} treatment

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Wonmo; Kim, Siyong; Kim, Jung-in; Lee, Jae-gi; Shin, Young-Joo; Jung, Jae-Yong; Ye, Sung-Joon [Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-799, South Korea and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744 (Korea, Republic of); Department of Radiation Oncology, Mayo Clinic, Jacksonville, Florida 32224 (United States); Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-799, South Korea and Department of Radiation Oncology, Kangbuk Samsung Medical Center, Seoul 110-746 (Korea, Republic of); Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744, South Korea and Department of Biomedical Radiation Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Department of Radiation Oncology, Sanggye Paik Hospital, Inje University, Seoul 139-707 (Korea, Republic of); Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of); Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744 (Korea, Republic of); Department of Biomedical Radiation Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Department of Radiation Oncology, Seoul National University, Seoul 110-799 (Korea, Republic of) and Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of)

    2012-10-15

    Purpose: To investigate dose perturbations for pacemaker-implanted patients in partial breast irradiation using high dose rate (HDR) balloon brachytherapy. Methods: Monte Carlo (MC) simulations were performed to calculate dose distributions involving a pacemaker in Ir-192 HDR balloon brachytherapy. Dose perturbations by varying balloon-to-pacemaker distances (BPD = 50 or 100 mm) and concentrations of iodine contrast medium (2.5%, 5.0%, 7.5%, and 10.0% by volume) in the balloon were investigated for separate parts of the pacemaker (i.e., battery and substrate). Relative measurements using an ion-chamber were also performed to confirm MC results. Results: The MC and measured results in homogeneous media without a pacemaker agreed with published data within 2% from the balloon surface to 100 mm BPD. Further their dose distributions with a pacemaker were in a comparable agreement. The MC results showed that doses over the battery were increased by a factor of 3, compared to doses without a pacemaker. However, there was no significant dose perturbation in the middle of substrate but up to 70% dose increase in the substrate interface with the titanium capsule. The attenuation by iodine contrast medium lessened doses delivered to the pacemaker by up to 9%. Conclusions: Due to inhomogeneity of pacemaker and contrast medium as well as low-energy photons in Ir-192 HDR balloon brachytherapy, the actual dose received in a pacemaker is different from the homogeneous medium-based dose and the external beam-based dose. Therefore, the dose perturbations should be considered for pacemaker-implanted patients when evaluating a safe clinical distance between the balloon and pacemaker.

  11. Unsplit bipolar pulse forming line

    Science.gov (United States)

    Rhodes, Mark A [Pleasanton, CA

    2011-05-24

    A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  12. Course of Subthreshold Bipolar Disorder in Youth: Diagnostic Progression from Bipolar Disorder Not Otherwise Specified

    Science.gov (United States)

    Axelson, David A.; Birmaher, Boris; Strober, Michael A.; Goldstein, Benjamin I.; Ha, Wonho; Gill, Mary Kay; Goldstein, Tina R.; Yen, Shirley; Hower, Heather; Hunt, Jeffrey I.; Liao, Fangzi; Iyengar, Satish; Dickstein, Daniel; Kim, Eunice; Ryan, Neal D.; Frankel, Erica; Keller, Martin B.

    2011-01-01

    Objective: To determine the rate of diagnostic conversion from an operationalized diagnosis of bipolar disorder not otherwise specified (BP-NOS) to bipolar I disorder (BP-I) or bipolar II disorder (BP-II) in youth over prospective follow-up and to identify factors associated with conversion. Method: Subjects were 140 children and adolescents…

  13. GABAergic neuroactive steroids: a new frontier in bipolar disorders?

    Directory of Open Access Journals (Sweden)

    Carta Mauro Giovanni

    2012-12-01

    Full Text Available Abstract Neurosteroids are synthesized in the brain and modulate brain excitability. There is increasing evidence of their sedative, anesthetic and antiseizure properties, as well as their influence on mood. Currently neurosteroids are classified as pregnane neurosteroids (allopregnanolone and allotetrahydrodeoxycorticosterone, androstane neurosteroids (androstanediol and etiocholanone or sulfated neurosteroids (pregnenolone sulfate and dehydroepiandrosterone sulfate. Both preclinical and clinical findings indicate that progesterone derivative neurosteroids such as allopregnanolone and allotetrahydrodeoxycorticosterone play a role in mood disorders. Clozapine and olanzapine, which were shown to be effective in stabilizing bipolar disorder, elevate pregnenolone levels in rat hippocampus, cerebral cortex, and serum. In lithium-treated mice, the blood levels of allopregnanolone and pregnenolone were elevated compared to control levels. Women diagnosed with bipolar disorder typically show symptomatic exacerbation in relation to the menstrual cycle, and show vulnerability to the onset or recurrence of mood disorders immediately after giving birth, when the levels of neurosteroid derivatives of progesterone drop. Whereas in women who had recovered from bipolar disorder, the plasma concentration of allopregnanolone was elevated compared to either healthy controls or women with major depressive disorder during the premenstrual period. During depressive episodes, blood level of allopregnanolone is low. Treatment with fluoxetine tends to stabilize the levels of neurosteroids in depression. These findings converge to suggest that these steroids have significant mood-stabilizing effect. This hypothesis is consistent with the observation that a number of anticonvulsants are effective therapies for bipolar disorder, a finding also consistent with the antiseizure properties of neurosteroids. Further exploration of action of neuroactive steroids is likely to

  14. Bipolar (spectrum) disorder and mood stabilization: standing at the crossroads?

    OpenAIRE

    De Fruyt, Jurgen; Demyttenaere, Koen

    2007-01-01

    Diagnosis and treatment of bipolar disorder has long been a neglected discipline. Recent years have shown an upsurge in bipolar research. When compared to major depressive disorder, bipolar research still remains limited and more expert based than evidence based. In bipolar diagnosis the focus is shifting from classic mania to bipolar depression and hypomania. There is a search for bipolar signatures in symptoms and course of major depressive episodes. The criteria for hypomania are softened,...

  15. Clinical application of transvenous temporary cardiac pacemaker in performing extra-cranial carotid angiography and stent implantation

    International Nuclear Information System (INIS)

    Liu Juan; Yao Guoen; Zhou Huadong; Jiang Xiaojiang; Chen Qiao

    2012-01-01

    Objective: To assess the safety and effectiveness of transvenous temporary cardiac pacemaker in preventing hemodynamic instability occurred during the perioperative period of extra-cranial carotid angiography and stent implantation. Methods: Preoperative install of temporary cardiac pacemaker via left femoral vein was carried out in 41 patients who were at high risk for developing hemodynamic instability, which was followed by extra-cranial carotid angiography and stent implantation. The pacing rhythm of the pacemaker was fixed at 60 beats/min. During and after the procedure the patients were under close observation for the signs of discomfort symptoms as well as the changes in blood pressure and heart rate. The working condition of the pacemaker was also monitored. Results: All the installed pacemakers were technically and hemodynamically effective in producing electrical ventricular responses in all 25 patients who had received balloon dilatation of carotid in advance. Transient pacemaker activation appeared in 25 patients. The longest activation time was one day. During pacemaker activation, one patient developed symptomatic hypotension. The longest duration of hypotension lasted for 4 days. No pacemaker-related or procedure-related complications occurred. Conclusion: Hemodynamic instability is a common complication occurred during perioperative period of extra-cranial carotid angiography and stent implantation. As a prophylactic measure, preoperative placement of temporary cardiac pacemaker can promptly and effectively correct the hemodynamic disorders and prevent perioperative complications such as stroke, etc. Therefore, this technique is worth employing in clinical practice, and it is especially useful for patients with high risks. (authors)

  16. [Bipolar disorders in DSM-5].

    Science.gov (United States)

    Severus, E; Bauer, M

    2014-05-01

    In spring 2013 the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) edited by the American Psychiatric Association was published. The DSM-5 has also brought some important changes regarding bipolar disorders. The goal of this manuscript is to review the novelties in DSM-5 and to evaluate the implications of these changes. The diagnostic criteria as well as the additional remarks provided in the running text of DSM-5 were carefully appraised. For the first time diagnostic criteria are provided for disorders which up to now have been considered as subthreshold bipolar disorders. Furthermore, mixed episodes were eliminated and instead a mixed specifier was introduced. An increase in goal-directed activity/energy is now one of the obligatory symptoms for a (hypo)manic episode. Diagnostic guidance is provided as to when a (hypo)manic episode that has developed during treatment with an antidepressant has to be judged to be causally related to antidepressants and when this episode has only occurred coincidentally with antidepressant use. While some of the novelties are clearly useful, e.g. addition of increased goal-directed activity/energy as obligatory symptom for (hypo)manic episodes, this remains to be demonstrated for others, such as the definition of various subthreshold bipolar disorders.

  17. Recent advances in understanding total-dose effects in bipolar transistors

    International Nuclear Information System (INIS)

    Schrimpf, R.D.

    1996-01-01

    Gain degradation in irradiated bipolar transistors can be a significant problem, particularly in linear integrated circuits. In many bipolar technologies, the degradation is greater for irradiation at low dose rates than it is for typical laboratory dose rates. Ionizing radiation causes the base current in bipolar transistors to increase, due to the presence of net positive charge in the oxides covering sensitive device areas and increases in surface recombination velocity. Understanding the mechanisms responsible for radiation-induced gain degradation in bipolar transistors is important in developing appropriate hardness assurance methods. This paper reviews recent modeling and experimental work, with the emphasis on low-dose-rate effects. A promising hardness assurance method based on irradiation at elevated temperatures is described

  18. The prevalence and correlates of alcohol use disorder amongst bipolar patients in a hospital setting, Malaysia.

    Science.gov (United States)

    Yee, Hway Ann; Loh, Huai Seng; Ng, Chong Guan

    2013-10-01

    To determine the prevalence of alcohol-use disorder and associated correlates amongst bipolar patients in a university hospital in Malaysia. In this cross-sectional study, a total of 121 bipolar disorder patients were included. Their alcohol use disorders were assessed with the Mini International Neuropsychiatric Interview (plus version) and the Addiction Severity Index-Lite-Clinical Factors version. The number of lifetime hospitalizations and the survival days (the number of days between the last discharge and the most current readmission) were calculated. The prevalence of alcohol-use disorder amongst bipolar patients was 18.2%. Indian ethnicity was the only demographic factor that was statistically associated with alcohol-use disorder (p rate of suicidal attempt (p Malaysia. Since alcohol-use disorder, as well as the potential interactions with the course of the disorder, is highly prevalent amongst bipolar patients, alcohol use should be addressed in these patients.

  19. Virginia Woolf, neuroprogression, and bipolar disorder

    Directory of Open Access Journals (Sweden)

    Manuela V. Boeira

    2016-01-01

    Full Text Available Family history and traumatic experiences are factors linked to bipolar disorder. It is known that the lifetime risk of bipolar disorder in relatives of a bipolar proband are 5-10% for first degree relatives and 40-70% for monozygotic co-twins. It is also known that patients with early childhood trauma present earlier onset of bipolar disorder, increased number of manic episodes, and more suicide attempts. We have recently reported that childhood trauma partly mediates the effect of family history on bipolar disorder diagnosis. In light of these findings from the scientific literature, we reviewed the work of British writer Virginia Woolf, who allegedly suffered from bipolar disorder. Her disorder was strongly related to her family background. Moreover, Virginia Woolf was sexually molested by her half siblings for nine years. Her bipolar disorder symptoms presented a pernicious course, associated with hospitalizations, suicidal behavioral, and functional impairment. The concept of neuroprogression has been used to explain the clinical deterioration that takes places in a subgroup of bipolar disorder patients. The examination of Virgina Woolf’s biography and art can provide clinicians with important insights about the course of bipolar disorder.

  20. [Lithium and anticonvulsants in bipolar depression].

    Science.gov (United States)

    Samalin, L; Nourry, A; Llorca, P-M

    2011-12-01

    For decades, lithium and anticonvulsants have been widely used in the treatment of bipolar disorder. Their efficacy in the treatment of mania is recognized. These drugs have been initially evaluated in old and methodologically heterogeneous studies. Their efficacy in bipolar depression has not always been confirmed in more recent and methodologically more reliable studies. Thus, lithium's efficacy as monotherapy was challenged by the study of Young (2008) that showed a lack of efficacy compared with placebo in the treatment of bipolar depression. In two recent meta-analyses, valproate has shown a modest efficacy in the treatment of bipolar depression. As for lithium, valproate appeared to have a larger antimanic effect for acute phase and prophylaxis of bipolar disorder. In contrast, lamotrigine is more effective on the depressive pole of bipolar disorder with better evidence for the prevention of depressive recurrences. The guidelines include these recent studies and recommend lamotrigine as a first-line treatment of bipolar depression and for maintenance treatment. Because of more discordant data concerning lithium and valproate, these two drugs are placed either as first or as second line treatment of bipolar depression. The different safety/efficacy ratios of mood stabilizers underlie the complementarity and the importance of combination between them, or with some second-generation antipsychotics, in the treatment of patients with bipolar disorder. Copyright © 2011 L’Encéphale. Published by Elsevier Masson SAS.. All rights reserved.

  1. Late Onset Bipolar Disorder: Case Report

    Directory of Open Access Journals (Sweden)

    Filipa Araújo

    2016-07-01

    Full Text Available Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1% in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad differential diagnosis and pharmacologic management when approaching new-onset manic/depressive symptoms among geriatric patients.

  2. Dysfunctional gaze processing in bipolar disorder

    Directory of Open Access Journals (Sweden)

    Cristina Berchio

    2017-01-01

    The present study provides neurophysiological evidence for abnormal gaze processing in BP and suggests dysfunctional processing of direct eye contact as a prominent characteristic of bipolar disorder.

  3. Does psychomotor agitation in major depressive episodes indicate bipolarity? Evidence from the Zurich Study.

    Science.gov (United States)

    Angst, Jules; Gamma, Alex; Benazzi, Franco; Ajdacic, Vladeta; Rössler, Wulf

    2009-02-01

    Kraepelin's partial interpretation of agitated depression as a mixed state of "manic-depressive insanity" (including the current concept of bipolar disorder) has recently been the focus of much research. This paper tested whether, how, and to what extent both psychomotor symptoms, agitation and retardation in depression are related to bipolarity and anxiety. The prospective Zurich Study assessed psychiatric and somatic syndromes in a community sample of young adults (N = 591) (aged 20 at first interview) by six interviews over 20 years (1979-1999). Psychomotor symptoms of agitation and retardation were assessed by professional interviewers from age 22 to 40 (five interviews) on the basis of the observed and reported behaviour within the interview section on depression. Psychiatric diagnoses were strictly operationalised and, in the case of bipolar-II disorder, were broader than proposed by DSM-IV-TR and ICD-10. As indicators of bipolarity, the association with bipolar disorder, a family history of mania/hypomania/cyclothymia, together with hypomanic and cyclothymic temperament as assessed by the general behavior inventory (GBI) [15], and mood lability (an element of cyclothymic temperament) were used. Agitated and retarded depressive states were equally associated with the indicators of bipolarity and with anxiety. Longitudinally, agitation and retardation were significantly associated with each other (OR = 1.8, 95% CI = 1.0-3.2), and this combined group of major depressives showed stronger associations with bipolarity, with both hypomanic/cyclothymic and depressive temperamental traits, and with anxiety. Among agitated, non-retarded depressives, unipolar mood disorder was even twice as common as bipolar mood disorder. Combined agitated and retarded major depressive states are more often bipolar than unipolar, but, in general, agitated depression (with or without retardation) is not more frequently bipolar than retarded depression (with or without agitation), and

  4. A systematic review on the role of anticonvulsants in the treatment of acute bipolar depression.

    Science.gov (United States)

    Reinares, María; Rosa, Adriane R; Franco, Carolina; Goikolea, José Manuel; Fountoulakis, Kostas; Siamouli, Melina; Gonda, Xenia; Frangou, Sophia; Vieta, Eduard

    2013-03-01

    Despite the high morbidity and mortality associated with bipolar depression, the optimal treatment for this phase is still a matter of debate. The aim of the current review was to provide updated evidence about the efficacy and tolerability of anticonvulsants in the treatment of acute bipolar depression. A comprehensive review of randomized controlled trials (RCTs) evaluating the use of anticonvulsants for the treatment of acute bipolar depression up to June 2011 was conducted by means of the PubMed-Medline database. Eligibility criteria included active comparator-controlled or placebo-controlled randomized studies involving monotherapy or combination therapy. A total of 18 RCTs fulfilled the inclusion criteria. Studies supported the efficacy of divalproex as monotherapy in acute bipolar depression but small sample size was a common methodological limitation. Findings were inconclusive for lamotrigine and carbamazepine although overall lamotrigine may have a beneficial but modest effect. Negative results were found for levetiracetam and gabapentin but the evidence base on these agents is scant. All anticonvulsants were generally well tolerated. No double-blind RCTs were found for the use of other anticonvulsants such as oxcarbazepine, licarbazepine, zonisamide, retigabine, pregabalin, tiagabine, felbamate and vigabatrine in the acute treatment of bipolar depression. To sum up, taking into consideration the efficacy and tolerability profiles of anticonvulsants, current evidence supports the use of divalproex and lamotrigine in the treatment of acute bipolar depression. However, available data for most other anticonvulsants are inconclusive and further RCTs with larger sample sizes are needed before drawing firm conclusions.

  5. Circadian pacemaking in cells and circuits of the suprachiasmatic nucleus.

    Science.gov (United States)

    Hastings, M H; Brancaccio, M; Maywood, E S

    2014-01-01

    The suprachiasmatic nucleus (SCN) of the hypothalamus is the principal circadian pacemaker of the brain. It co-ordinates the daily rhythms of sleep and wakefulness, as well as physiology and behaviour, that set the tempo to our lives. Disturbance of this daily pattern, most acutely with jet-lag but more insidiously with rotational shift-work, can have severely deleterious effects for mental function and long-term health. The present review considers recent developments in our understanding of the properties of the SCN that make it a robust circadian time-keeper. It first focuses on the intracellular transcriptional/ translational feedback loops (TTFL) that constitute the cellular clockwork of the SCN neurone. Daily timing by these loops pivots around the negative regulation of the Period (Per) and Cryptochrome (Cry) genes by their protein products. The period of the circadian cycle is set by the relative stability of Per and Cry proteins, and this can be controlled by both genetic and pharmacological interventions. It then considers the function of these feedback loops in the context of cytosolic signalling by cAMP and intracellular calcium ([Ca(2+) ]i ), which are both outputs from, and inputs to, the TTFL, as well as the critical role of vasoactive intestinal peptide (VIP) signalling in synchronising cellular clocks across the SCN. Synchronisation by VIP in the SCN is paracrine, operating over an unconventionally long time frame (i.e. 24 h) and wide spatial domain, mediated via the cytosolic pathways upstream of the TTFL. Finally, we show how intersectional pharmacogenetics can be used to control G-protein-coupled signalling in individual SCN neurones, and how manipulation of Gq/[Ca(2+) ]i -signalling in VIP neurones can re-programme the circuit-level encoding of circadian time. Circadian pacemaking in the SCN therefore provides an unrivalled context in which to understand how a complex, adaptive behaviour can be organised by the dynamic activity of a relatively

  6. Leadless Cardiac Pacemaker Implantation After Lead Extraction in Patients With Severe Device Infection.

    Science.gov (United States)

    Kypta, Alexander; Blessberger, Hermann; Kammler, Juergen; Lambert, Thomas; Lichtenauer, Michael; Brandstaetter, Walter; Gabriel, Michael; Steinwender, Clemens

    2016-09-01

    Conventional pacemaker therapy is limited by short- and long-term complications, most notably device infection. Transcatheter pacing systems (TPS) may be beneficial in this kind of patients as they eliminate the need for a device pocket and leads and thus may reduce the risk of re-infection. We assessed a novel procedure in 6 patients with severe device infection who were pacemaker dependent. After lead extraction a single chamber TPS was implanted into the right ventricle. Of the 6 patients who underwent lead extraction due to severe device infection at our institution, 3 were diagnosed with a pocket infection only, whereas the other 3 showed symptoms of both pocket and lead infection. Successful lead extraction and TPS implantation was accomplished in all patients. Four patients were bridged with a temporary pacemaker between 2 hours and 2 days after lead extraction, whereas 2 patients had the TPS implanted during the same procedure just before traditional pacemaker system removal. All patients stayed free of infection during the follow-up period of 12 weeks. An additional positron emission tomography scan was performed in each patient and indicated no signs of an infection around the TPS. Transcather pacemaker implantation was safe and feasible in 6 patients and did not result in re-infection even if implanted before removal of the infected pacemaker system within the same procedure. Therefore, implantation of a TPS may be an option for patients with severe device infection, especially in those with blocked venous access or who are pacemaker dependent. © 2016 Wiley Periodicals, Inc.

  7. Placement Of Cardiac PacemaKEr Trial (POCKET – rationale and design: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Peter Magnusson

    2017-04-01

    Full Text Available Background: A pacemaker system consists of one or two leads connected to a device that is implanted into a pocket formed just below the collarbone. This pocket is typically subcutaneous, that is, located just above the pectoral fascia. Even though the size of pacemakers has decreased markedly, complications due to superficial implants do occur. An alternative technique would be intramuscular placement of the pacemaker device, but there are no randomized controlled trials (RCTs to support this approach, which is the rationale for the Placement Of Cardiac PacemaKEr Trial (POCKET. The aim is to study if intramuscular is superior to subcutaneous placement of a pacemaker pocket. Methods: In October 2016, we started to enroll 200 consecutive patients with an indication for bradycardia pacemaker implantation. Patients are randomized to random block sizes, stratified by age group (cut-off: 65 years and sex, and then randomized to either subcutaneous or intramuscular implant. A concealed allocation procedure is employed, using sequentially numbered, sealed envelopes. Pocket site is blinded to the patient and in all subsequent care. The primary endpoint is patient overall satisfaction with the pocket location at 24 months as measured using a visual analog scale (VAS 0-10. Secondary endpoints are: complications, patient-reported satisfaction at 1, 12, and 24 months (overall satisfaction, pain, discomfort, degree of unsightly appearance, movement problems, and sleep problems due to device. Conclusions: POCKET is a prospective interventional RCT designed to evaluate if intramuscular is superior to subcutaneous placement of a bradycardia pacemaker during a two-year follow-up.

  8. Long-Term Mortality Effect of Early Pacemaker Implantation After Surgical Aortic Valve Replacement.

    Science.gov (United States)

    Greason, Kevin L; Lahr, Brian D; Stulak, John M; Cha, Yong-Mei; Rea, Robert F; Schaff, Hartzell V; Dearani, Joseph A

    2017-10-01

    The need for pacemaker implantation is a well-described complication of aortic valve replacement. Not so well described is the effect such an event has on long-term outcome. This study reviewed a 21-year experience at the Mayo Clinic (Rochester, Minnesota) with aortic valve replacement to understand the influence of early postoperative pacemaker implantation on long-term mortality rates more clearly. This study retrospectively reviewed the records of 5,842 patients without previous pacemaker implantation who underwent surgical aortic valve replacement from January 1993 through June 2014. The median age of these patients was 73 years (range, 65 to 79 years), the median ejection fraction was 62% (range, 53% to 68%), 3,853 patients were male (66%), and coronary artery bypass graft operation was performed in 2,553 (44%) of the patients studied. Early pacemaker implantation occurred in 146 patients (2.5%) within 30 days of surgical aortic valve replacement. The median follow-up of patients was 11.1 years (range, 5.8 to 16.5 years), and all-cause mortality rates were 2.4% at 30 days, 6.4% at 1 year, 23.1% at 5 years, 48.3% at 10 years, and 67.9% at 15 years postoperatively. Early pacemaker implantation was associated with an increased risk of death after multivariable adjustment for baseline patients' characteristics (hazard ratio, 1.49; 95% confidence interval, 1.20, 1.84; p pacemaker implantation as a complication of surgical aortic valve replacement is associated with an increased risk of long-term death. Valve replacement-related pacemaker implantation rates should be important considerations with respect to new valve replacement paradigms, especially in younger and lower-risk patients. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Case study thoracic radiotherapy in an elderly patient with pacemaker: The issue of pacing leads

    Energy Technology Data Exchange (ETDEWEB)

    Kirova, Youlia M., E-mail: youlia.kirova@curie.net [Department of Radiation Oncology, Institut Curie, Paris (France); Menard, Jean; Chargari, Cyrus; Mazal, Alejandro [Department of Radiation Oncology, Institut Curie, Paris (France); Kirov, Krassen [Department of Anesthesiology and Reanimation, Institut Curie, Paris (France)

    2012-07-01

    To assess clinical outcome of patients with pacemaker treated with thoracic radiation therapy for T8-T9 paravertebral chloroma. A 92-year-old male patient with chloroma presenting as paravertebral painful and compressive (T8-T9) mass was referred for radiotherapy in the Department of Radiation Oncology, Institut Curie. The patient presented with cardiac dysfunction and a permanent pacemaker that had been implanted prior. The decision of Multidisciplinary Meeting was to deliver 30 Gy in 10 fractions for reducing the symptoms and controlling the tumor growth. The patient received a total dose of 30 Gy in 10 fractions using 4-field conformal radiotherapy with 20-MV photons. The dose to pacemaker was 0.1 Gy but a part of the pacing leads was in the irradiation fields. The patient was treated the first time in the presence of his radiation oncologist and an intensive care unit doctor. Moreover, the function of his pacemaker was monitored during the entire radiotherapy course. No change in pacemaker function was observed during any of the radiotherapy fractions. The radiotherapy was very well tolerated without any side effects. The function of the pacemaker was checked before and after the radiotherapy treatment by the cardiologist and no pacemaker dysfunction was observed. Although updated guidelines are needed with acceptable dose criteria for implantable cardiac devices, it is possible to treat patients with these devices and parts encroaching on the radiation field. This case report shows we were able to safely treat our patient through a multidisciplinary approach, monitoring the patient during each step of the treatment.

  10. Case study thoracic radiotherapy in an elderly patient with pacemaker: The issue of pacing leads

    International Nuclear Information System (INIS)

    Kirova, Youlia M.; Menard, Jean; Chargari, Cyrus; Mazal, Alejandro; Kirov, Krassen

    2012-01-01

    To assess clinical outcome of patients with pacemaker treated with thoracic radiation therapy for T8-T9 paravertebral chloroma. A 92-year-old male patient with chloroma presenting as paravertebral painful and compressive (T8-T9) mass was referred for radiotherapy in the Department of Radiation Oncology, Institut Curie. The patient presented with cardiac dysfunction and a permanent pacemaker that had been implanted prior. The decision of Multidisciplinary Meeting was to deliver 30 Gy in 10 fractions for reducing the symptoms and controlling the tumor growth. The patient received a total dose of 30 Gy in 10 fractions using 4-field conformal radiotherapy with 20-MV photons. The dose to pacemaker was 0.1 Gy but a part of the pacing leads was in the irradiation fields. The patient was treated the first time in the presence of his radiation oncologist and an intensive care unit doctor. Moreover, the function of his pacemaker was monitored during the entire radiotherapy course. No change in pacemaker function was observed during any of the radiotherapy fractions. The radiotherapy was very well tolerated without any side effects. The function of the pacemaker was checked before and after the radiotherapy treatment by the cardiologist and no pacemaker dysfunction was observed. Although updated guidelines are needed with acceptable dose criteria for implantable cardiac devices, it is possible to treat patients with these devices and parts encroaching on the radiation field. This case report shows we were able to safely treat our patient through a multidisciplinary approach, monitoring the patient during each step of the treatment.

  11. Placement Of Cardiac PacemaKEr Trial (POCKET – rationale and design: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Peter Magnusson

    2017-04-01

    Full Text Available BackgroundA pacemaker system consists of one or two leads connected to a device that is implanted into a pocket formed just below the collarbone. This pocket is typically subcutaneous, that is, located just above the pectoral fascia. Even though the size of pacemakers has decreased markedly, complications due to superficial implants do occur. An alternative technique would be intramuscular placement of the pacemaker device, but there are no randomized controlled trials (RCTs to support this approach, which is the rationale for the Placement Of Cardiac PacemaKEr Trial (POCKET. The aim is to study if intramuscular is superior to subcutaneous placement of a pacemaker pocket.MethodsIn October 2016, we started to enroll 200 consecutive patients with an indication for bradycardia pacemaker implantation. Patients are randomized to random block sizes, stratified by age group (cut-off: 65 years and sex, and then randomized to either subcutaneous or intramuscular implant. A concealed allocation procedure is employed, using sequentially numbered, sealed envelopes. Pocket site is blinded to the patient and in all subsequent care. The primary endpoint is patient overall satisfaction with the pocket location at 24 months as measured using a visual analog scale (VAS 0-10. Secondary endpoints are: complications, patient-reported satisfaction at 1, 12, and 24 months (overall satisfaction, pain, discomfort, degree of unsightly appearance, movement problems, and sleep problems due to device.ConclusionsPOCKET is a prospective interventional RCT designed to evaluate if intramuscular is superior to subcutaneous placement of a bradycardia pacemaker during a two-year follow-up.

  12. Ectopic jejunal pacemakers and gastric emptying after Roux gastrectomy: Effect of intestinal pacing

    International Nuclear Information System (INIS)

    Karlstrom, L.; Kelly, K.A.

    1989-01-01

    The aims of this study were to determine whether ectopic pacemakers are present after meals in the Roux limbs of dogs after vagotomy and Roux gastrectomy, whether these pacemakers slow gastric emptying of liquids or solids, and whether abolishing the pacemakers with electric pacing might speed any slow emptying that occurs. In six dogs that underwent vagotomy and Roux gastrectomy and in four dogs that underwent vagotomy and Billroth gastrectomy (controls), myoelectric activity of the Roux limb or duodenum was measured during gastric emptying of a 500 kcal mixed meal of 99mTc-labeled cooked egg and 111In-labeled milk. Roux dogs were tested with and without pacing of the Roux limb. Roux dogs showed ectopic pacemaker in the Roux limb that drove the pacesetter potentials of the limb in a reverse, or orad, direction during 57% of the postprandial recordings. Billroth dogs had no ectopic pacemakers (p less than 0.05). Liquids emptied more slowly in Roux dogs (half-life (t1/2) = 121 +/- 15 minutes) than in Billroth dogs (t1/2 = 43 +/- 9 minutes; p less than 0.05), but solids emptied similarly in both groups of dogs (t1/2 approximately 8 hours). Pacing the Roux limb abolished the ectopic pacemakers, restored the slow emptying of liquids to the more rapid rate found in the Billroth dogs (t1/2: paced Roux, 72 +/- 15 minutes; Billroth, 43 +/- 9 minutes; p greater than 0.05) and did not change emptying of solids. The conclusion was that ectopic pacemakers present in the Roux limb after vagotomy and Roux gastrectomy drove the limb in a reverse direction and slowed emptying of liquids after the operation. The defect was corrected by pacing the Roux limb in a forward direction

  13. Ectopic jejunal pacemakers and gastric emptying after Roux gastrectomy: Effect of intestinal pacing

    Energy Technology Data Exchange (ETDEWEB)

    Karlstrom, L.; Kelly, K.A. (Mayo Clinic, Rochester, MN (USA))

    1989-11-01

    The aims of this study were to determine whether ectopic pacemakers are present after meals in the Roux limbs of dogs after vagotomy and Roux gastrectomy, whether these pacemakers slow gastric emptying of liquids or solids, and whether abolishing the pacemakers with electric pacing might speed any slow emptying that occurs. In six dogs that underwent vagotomy and Roux gastrectomy and in four dogs that underwent vagotomy and Billroth gastrectomy (controls), myoelectric activity of the Roux limb or duodenum was measured during gastric emptying of a 500 kcal mixed meal of 99mTc-labeled cooked egg and 111In-labeled milk. Roux dogs were tested with and without pacing of the Roux limb. Roux dogs showed ectopic pacemaker in the Roux limb that drove the pacesetter potentials of the limb in a reverse, or orad, direction during 57% of the postprandial recordings. Billroth dogs had no ectopic pacemakers (p less than 0.05). Liquids emptied more slowly in Roux dogs (half-life (t1/2) = 121 +/- 15 minutes) than in Billroth dogs (t1/2 = 43 +/- 9 minutes; p less than 0.05), but solids emptied similarly in both groups of dogs (t1/2 approximately 8 hours). Pacing the Roux limb abolished the ectopic pacemakers, restored the slow emptying of liquids to the more rapid rate found in the Billroth dogs (t1/2: paced Roux, 72 +/- 15 minutes; Billroth, 43 +/- 9 minutes; p greater than 0.05) and did not change emptying of solids. The conclusion was that ectopic pacemakers present in the Roux limb after vagotomy and Roux gastrectomy drove the limb in a reverse direction and slowed emptying of liquids after the operation. The defect was corrected by pacing the Roux limb in a forward direction.

  14. Pacemakers in patients with familial dysautonomia--a review of experience with 20 patients.

    Science.gov (United States)

    Gold-von Simson, Gabrielle; Rutkowski, Monika; Berlin, Dena; Axelrod, Felicia B

    2005-02-01

    Familial dysautonomia (FD) is a genetic disease associated with a high incidence of sudden death. If fatal bradyarrhythmia is an etiological factor then the incidence of sudden death should decrease after pacemaker placement. Retrospective review of 596 registered FD patients revealed that 22 FD patients (3.7%) had pacemakers placed between December 1984 and June 2003. Clinical and electrocardiographic indications for placement and demographic data were assessed for 20 of the 22 patients (10 males, 10 females, ages 4 to 48 years). Two patients were excluded because of insufficient data. Prior to pacemaker placement, presenting symptoms were syncope and cardiac arrest, 16/20 (80%) and 6/20 (30 %), respectively. Asystole was the most frequent electrocardiographic finding and was documented in 17/20 patients (85 %). Other electrocardiographic abnormalities included bradycardia, AV block, prolonged QTc and prolonged JTc. The average duration of pacemaker utilization was 5.7 years (range 5 months to 14.5 years). Complications included infection (1 patient) and wire migration (2 patients). In the one patient with infection, the pacemaker was permanently removed. This patient then experienced multiple syncopal episodes and death. There were 7 other deaths. Three deaths occurred suddenly without preceding events, and 4 patients had non-cardiac causes of death. None of these 7 deceased patients had recurrence of syncope after pacemaker placement. In the 12 surviving patients, 6 had recurrence of syncope but none had cardiac arrest. Pacemaker placement may protect FD patients from fatal bradyarrhythmia and may decrease the incidence of syncope. However, data are limited and prospective analysis is needed.

  15. Cardiac pacemaker battery discharge after external electrical cardioversion for broad QRS Complex Tachycardia.

    Science.gov (United States)

    Annamaria, Martino; Andrea, Scapigliati; Michela, Casella; Tommaso, Sanna; Gemma, Pelargonio; Antonio, Dello Russo; Roberto, Zamparelli; Stefano, De Paulis; Fulvio, Bellocci; Rocco, Schiavello

    2008-08-01

    External electrical cardioversion or defibrillation may be necessary in patients with implanted cardiac pacemaker (PM) or implantable cardioverter defibrillator (ICD). Sudden discharge of high electrical energy employed in direct current (DC) transthoracic countershock may damage the PM/ICD system resulting in a series of possible device malfunctions. For this reason, when defibrillation or cardioversion must be attempted in a patient with a PM or ICD, some precautions should be taken, particularly in PM dependent patients, in order to prevent damage to the device. We report the case of a 76-year-old woman with a dual chamber PM implanted in the right subclavicular region, who received two consecutive transthoracic DC shocks to treat haemodynamically unstable broad QRS complex tachycardia after cardiac surgery performed with a standard sternotomic approach. Because of the sternal wound and thoracic drainage tubes together with the severe clinical compromise, the anterior paddle was positioned near the pulse generator. At the following PM test, a complete battery discharge was detected.

  16. Bipolar mixed features - Results from the comparative effectiveness for bipolar disorder (Bipolar CHOICE) study.

    Science.gov (United States)

    Tohen, Mauricio; Gold, Alexandra K; Sylvia, Louisa G; Montana, Rebecca E; McElroy, Susan L; Thase, Michael E; Rabideau, Dustin J; Nierenberg, Andrew A; Reilly-Harrington, Noreen A; Friedman, Edward S; Shelton, Richard C; Bowden, Charles L; Singh, Vivek; Deckersbach, Thilo; Ketter, Terence A; Calabrese, Joseph R; Bobo, William V; McInnis, Melvin G

    2017-08-01

    DSM-5 changed the criteria from DSM-IV for mixed features in mood disorder episodes to include non-overlapping symptoms of depression and hypomania/mania. It is unknown if, by changing these criteria, the same group would qualify for mixed features. We assessed how those meeting DSM-5 criteria for mixed features compare to those meeting DSM-IV criteria. We analyzed data from 482 adult bipolar patients in Bipolar CHOICE, a randomized comparative effectiveness trial. Bipolar diagnoses were confirmed through the MINI International Neuropsychiatric Interview (MINI). Presence and severity of mood symptoms were collected with the Bipolar Inventory of Symptoms Scale (BISS) and linked to DSM-5 and DSM-IV mixed features criteria. Baseline demographics and clinical variables were compared between mood episode groups using ANOVA for continuous variables and chi-square tests for categorical variables. At baseline, the frequency of DSM-IV mixed episodes diagnoses obtained with the MINI was 17% and with the BISS was 20%. Using DSM-5 criteria, 9% of participants met criteria for hypomania/mania with mixed features and 12% met criteria for a depressive episode with mixed features. Symptom severity was also associated with increased mixed features with a high rate of mixed features in patients with mania/hypomania (63.8%) relative to those with depression (8.0%). Data on mixed features were collected at baseline only and thus do not reflect potential patterns in mixed features within this sample across the study duration. The DSM-5 narrower, non-overlapping definition of mixed episodes resulted in fewer patients who met mixed criteria compared to DSM-IV. Copyright © 2017. Published by Elsevier B.V.

  17. Differences in the ICD-10 diagnostic subtype of depression in bipolar disorder compared to recurrent depressive disorder

    DEFF Research Database (Denmark)

    Jensen, H.M.; Christensen, E.M.; Kessing, Lars Vedel

    2008-01-01

    Background: The aim of the study was to investigate whether patients with bipolar depression and patients with recurrent depressive disorder present with different subtypes of depressive episode as according to ICD-10. Sampling and Methods: All patients who got a diagnosis of bipolar affective...... disorder, current episode of depression, or a diagnosis of recurrent depressive disorder, current episode of depression, in a period from 1994 to 2002 at the first outpatient treatment or at the first discharge from psychiatric hospitalization in Denmark were identified in a nationwide register. Results......: Totally, 389 patients got a diagnosis of bipolar disorder, current episode of depression, and 5.391 patients got a diagnosis of recurrent depressive disorder, current episode of depression, at first contact. Compared with patients with a diagnosis of recurrent depressive disorder, patients with bipolar...

  18. Prevalence of cognitive impairment in major depression and bipolar disorder.

    Science.gov (United States)

    Douglas, Katie M; Gallagher, Peter; Robinson, Lucy J; Carter, Janet D; McIntosh, Virginia Vw; Frampton, Christopher Ma; Watson, Stuart; Young, Allan H; Ferrier, I Nicol; Porter, Richard J

    2018-05-01

    The current study examines prevalence of cognitive impairment in four mood disorder samples, using four definitions of impairment. The impact of premorbid IQ on prevalence was examined, and the influence of treatment response. Samples were: (i) 58 inpatients in a current severe depressive episode (unipolar or bipolar), (ii) 69 unmedicated outpatients in a mild to moderate depressive episode (unipolar or bipolar), (iii) 56 outpatients with bipolar disorder, in a depressive episode, and (iv) 63 outpatients with bipolar disorder, currently euthymic. Cognitive assessment was conducted after treatment in Studies 1 (6 weeks of antidepressant treatment commenced on admission) and 2 (16-week course of cognitive behaviour therapy or schema therapy), allowing the impact of treatment response to be assessed. All mood disorder samples were compared with healthy control groups. The prevalence of cognitive impairment was highest for the inpatient depression sample (Study 1), and lowest for the outpatient depression sample (Study 2). Substantial variability in rates was observed depending on the definition of impairment used. Correcting cognitive performance for premorbid IQ had a significant impact on the prevalence of cognitive impairment in the inpatient depression sample. There was minimal evidence that treatment response impacted on prevalence of cognitive impairment, except in the domain of psychomotor speed in inpatients. As interventions aiming to improve cognitive outcomes in mood disorders receive increasing research focus, the issue of setting a cut-off level of cognitive impairment for screening purposes becomes a priority. This analysis demonstrates important differences in samples likely to be recruited depending on the definition of cognitive impairment and begins to examine the importance of premorbid IQ in determining who is impaired. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. [Everyday stress, routines and bipolar spectrum].

    Science.gov (United States)

    Gindre, C; Swendsen, J

    2010-06-01

    Bipolar patients relapse more frequently under conditions of stress, even when compliant with prescribed medication. Although the biological bases of stress reactivity remain widely debated, the disruption of biological or circadian rhythms has been suggested as one possible mechanism through which stress increases the risk of episodes. This hypothesis has gained support from recent evidence demonstrating that the disruption of social rhythms is particularly implicated in the onset of manic episodes. However, it is currently unknown to what extent bipolar patients may differ from normal controls in terms of the basic prevalence and nature of daily life routines, or if such individuals are more sensitive to the disruption of such rhythms following exposure to stress. Using a dimensional perspective of bipolar disorder, 1728 French university students were first screened concerning diverse psychological and clinical characteristics. Two hundred and twelve individuals at high or low-risk for mood and substance use disorders were then invited to participate in a week-long period of ambulatory monitoring using the experience sampling method (ESM). During this phase, participants were given a preprogrammed PDA microcomputer which provided ambulatory assessments of behaviour and stress at fixed intervals (randomized across participants). At the end of the ESM phase, the microcomputers were collected and structured diagnostic interviews were administered to each participant. For the purposes of the current study, analyses focused on a subsample of 92 individuals, reflecting the 28 participants who met lifetime criteria for a manic (n=15) or hypomanic episode (n=13), and the 64 individuals who were free of any lifetime disorder. Data were analyzed using hierarchical nonlinear (Bernoulli) models for repeated measures. Covariates included age, sex, frequency of substance use and cognitive vulnerabilities assessed at screening. A Bonferroni correction was applied to adjust

  20. Y2K: effects on pacemaker and implantable defibrillator programmers.

    Science.gov (United States)

    Flynn, D P; Daubert, J P; Huang, D T; Ocampo, C M; O'Gorman, E

    1999-01-01

    All permanent pacemakers and implantable defibrillators (PPM/ICDs) will continue to function as programmed without regard to the date in the year 2000 (Y2K). All manufacturers contacted reassured us that some of these devices incorporate a day/year clock in the circuitry; however, these are not involved in sensing or delivering programmed therapy. Some manufacturers' device programmers will roll over to the year 2000 without any problems at all, whereas others may have difficulty with date and time stamping on printed reports. We tested 14 different types of PPM/ICD programmers for Y2K compliance using 8 tests. Five of the 14 models passed each test and were labeled at our institution with a green "Y2K" sticker to identify them as Y2K compatible and needing no special attention after December 31, 1999. The most common test failed was the ability to roll the date forward from December 31, 1999, with the programmer power off. Organizations should consider testing and replacing noncompliant device programmers or placing a red sticker with "Y2K" crossed out on noncompliant pieces. The red sticker alerts the advanced practice nurse or physician to the need to confirm the appropriate date and time in the programmer after startup in the year 2000 and before interrogating or programming any PPM/ICD, to avoid inappropriate date and time stamping on printed reports from that programmer.