Spelling suggestions: "subject:"heart beating"" "subject:"peart beating""
1 |
A survey of medical doctor's views on cadaveric organ donation and transplantation.Dickson, Lindy. January 2001 (has links)
The views of medical doctors regarding organ donation and transplantation in the Durban Metropolitan Region were examined in an exploratory and explanatory study, which included a descriptive, convenience sampled study of 43 graduate and postgraduate professionals, practicing in the private and provincial sectors. Characteristics were obtained from a 1 D6-item questionnaire that were later divided into component contributions according to Fazio's attitude to behavior process model (Fazio, 1989; Fazio & RoskosEewoldson, 1994). Variables which were analysed included personal demographics, personal views, knowledge and skills, practice-related issues, attitudes and perceptions as well as future recommendations. Analysis of the information revealed that most medical doctors approved of organ donation practices and viewed transplantation as a significant roleplayer in both the community and medical sectors. However, a knowledge and skills deficit combined with religious presumptions and general uncertainty regarding issues surrounding the practical, legal and emotional concepts of brain death may be responsible for the relatively low personal dedication and practice participation rate among the sample. Medical doctors from the provincial sector appeared to have considerable concerns which included: time constraints; a perceived lack of support from colleagues, nurses and hospital administrators; a lack of medico-Iegal awareness relating to organ donation and brain death and a scarcity of experience and insight into the transplant process. In order to address the paucity of awareness pertaining to brain death and organ donation activities, the findings indicate that formal and interactive education programs during the undergraduate, postgraduate and medical development phases are required in which issues surrounding death and dying can be explored by a multidisciplinary team. It appears that this team must comprise of doctors, lawyers, religious leaders, psychologists, administrators, nurses, donor families and transplant co-ordinators. This development may serve to emphasize the professional importance of holistic bereavement counseling, improve doctor and patient satisfaction, increase organ donation referrals and transplantation rates as well as diminish medico-Iegal concerns. / Thesis (M.Cur.)-University of Natal, Durban, 2001.
|
2 |
Effects of Isoproterenol on IhERG during K+ changes in HEK293 cellsZhang, J., Shang, Lijun, Wang, T., Ni, Y., Ma, A. January 2017 (has links)
Yes / Introduction:The human ether-a-go-go related gene (hERG) encodes the pore forming protein which mediates the rapid delayed rectifier K+ current in the heart (IKr). Together with other ion channels hERG determines the cardiac action potential and regulates the heart beating. Dysfuction of the hERG ion channel will lead to acquired long QT syndrome (LQTS). Therefore, new drug candidates must pass the test for a potential inhibitory effect on the hERG current as a first step in a nonclinical testing strategy.
Arrhythmias in patients with LQTS are typically triggered during physical or emotional stress, suggesting a link between sympathetic stimulation and arrhythmias. It is well known that potassium level can affect the QT interval through affecting IhERG both in vivo and in vitro.In this study, we try to find out whether the trigger effect still exist when K+ changes violently in a short time period. In other words, whether the risk of TdP aggravate when patients suffer from acute water electrolyte balance disorder, which is a common symptom in hot weather.
Methods: HEK293 Cell line stably expressing hERG channel were cultured in DMEM supplemented with 10% of fetal bovine serum.Whole-cell patch-clamp method was applied for ionic current recordings. The compositions of pipette was (in mM) 125 KCl, 5 MgCl2, 5 EGTA-K, 10 HEPES-K and 5 Na-ATP adjusted to pH 7.2 with KOH. The bath solutions for recording the IhERG currents was 136 NaCl, 4 KCl, 1 MgCl2, 10 HEPES-Na, 1.8 CaCl2 and 10 glucose, pH 7.4 with NaOH. The low extracellular K+ solution was 115 KCl, 5 MgCl2, 5 EGTA-K, 10 HEPES-K and 10 Na-ATP adjusted to pH 7.2 with NaOH. Patch-clamp experiments were performed at room temperature (22 ± 1°C). The recording of low K+ current was carried out immediately after the original normal K+ solution has been totally replaced. Isoproterenol (ISO) 100nM was added into both kinds of K+ solution to apply the effect of β1-AR stimulation.
Results: We found that low K+ solution increased IhERG from 907.39±18.68to 1620.08±249.44pA(n=30,P<0.05); Low K+also shifted the I-V curve to the left. IC50 in control is 10.31±5.52 mV, low K+ is -6.15±1.58 mV. When adding ISO 100nM to extracellular solution, same effects were shown for both groups.ISO decreased Imax for both group. In control group, Imax reduced from 907.39±18.68to493.16±54.41pA (n=30, P<0.01), while in low K+ group, I max decreased Imax from 1620.08±29.44to 488.48±81.87pA(n=30,P<0.05). At the same time, ISO shifts the I-V curve to the right for the control group and shift the curve to the left for low K+ group. IC50 in control when added ISO is 22.25±3.80 mV, while IC50 in low K+ group after adding 100nM ISO is -31.00±5.73 mV. Conclusion: The results from this study is contradict to those in our previous study where low K+ combined with ISO can lead to temporarily increase of QT interval in vivo.It is reported that an increase in net outward repolarizing current, due to a relatively large increase of IKs, is responsible for the changes of QT interval in response to beta-adrenergic stimulation in vivo(2). Therefore future studies need to co-transfect IKs channel to confirm this.
References:
1. Guo J, Massaeli H, Xu J, Jia Z, Wigle JT, Mesaeli N, et al. Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines. The Journal of clinical investigation. 2009;119(9):2745- 57.
2. Shimizu W, Antzelevitch C. Differential effects of beta-adrenergic agonists and antagonists in LQT1, LQT2 and LQT3 models of the long QT syndrome. Journal of the American College of Cardiology. 2000;35(3):778-86.
|
3 |
Efeito do pré-condicionamento isquêmico remoto no transplante ortotópico de fígado de doadores em parada cardíaca. Estudo experimental em suínos / Effect of remote ischemic preconditioning on liver orthotopic transplantation of non-heart-beating donors. Experimental study in pigsMorais, Lúcio Kenny 27 April 2012 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2017-12-18T19:17:24Z
No. of bitstreams: 2
Dissertação - Lúcio Kenny Morais - 2012.pdf: 9402569 bytes, checksum: 89e112868051e02f9a662b75b5fff235 (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-12-19T12:09:12Z (GMT) No. of bitstreams: 2
Dissertação - Lúcio Kenny Morais - 2012.pdf: 9402569 bytes, checksum: 89e112868051e02f9a662b75b5fff235 (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-12-19T12:09:12Z (GMT). No. of bitstreams: 2
Dissertação - Lúcio Kenny Morais - 2012.pdf: 9402569 bytes, checksum: 89e112868051e02f9a662b75b5fff235 (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Previous issue date: 2012-04-27 / Introduction: Improved liver function from non-heart-beating donors seems to be related
to short periods of warm ischemia; hence ischemia-reperfusion injury is a critical unsolved
issue. Remote Ischemic preconditioning (PC) has been shown to protect the liver from
ischemia-reperfusion injury. However little is known about the usefulness of ischemic
precondition as a strategy to improve tolerance of non-heart-beating liver grafts to warm
ischemia. Therefore we designed an experimental study aiming the effects of ischemic
preconditioning on liver transplantation from non-heart-beating donors.
Methods: Protocol was approved by Federal University of Goias Ethics Committee. Twentyfour
Landrace pigs were assigned into 4 groups: I: after cardiac arrest livers were procured
and transplanted; II: after PC and cardiac arrest livers were procured and transplanted; III:
after PC and cardiac arrest, a 15 minutes period of warm ischemia was observed before
livers were procured and transplanted; IV: after PC and cardiac arrest, a 30 minutes period
of warm ischemia was observed before livers were procured and transplanted. Donors:
cardiac arrest was obtained by ligation of coronary arteries and interruption of ventilation.
PC (10` x 10`) and warm ischemia waiting time were observed accordingly. Livers were
flushed with 4°C HTK solution cooled and procured. Recipients: standard technique was
used. After one hour of reperfusion, blood and liver samples were collected and euthanasia
was carried out. Non-parametrical statistical tests were applied. Results were expressed as
medians. A value of p<0.05 was considered statistically significant.
Results: AST, ALT, lactic acid and factor V levels were similar for the different studied
groups by the end of one hour of reperfusion. A trend towards a deteriorated liver function
was observed in group IV. When histological variables were addressed, vacuolization of
hepatocytes and cell dropout scores were similar in all groups. Congestion score,
vacuolization of hepatocytes and cell dropout scores tended to be higher in animals from
group IV, but with no statistical significance.
Conclusions: Remote ischemic preconditioning showed no benefits to liver grafts from nonheart-
beating donors. Even though it did not result in benefits, no prejudice could be noticed
in this research, as well. / Introdução: A melhora na função hepática em doadores de coração parado parece estar
relacionada a curtos períodos de isquemia normotérmica, logo a lesão de isquemia e
reperfusão é uma questão crucial não resolvida. O pré-condicionamento isquémico remoto
(PC), promove proteção ao fígado da lesão de isquemia e reperfusão. No entanto, pouco se
sabe sobre a utilidade do PC como uma estratégia para melhorar a tolerância de enxertos de
doadores em parada cardíaca frente à isquemia normotérmica. Portanto, foi desenvolvido um
estudo experimental visando os efeitos do pré-condicionamento isquêmico no transplante de
fígado de doadores em parada cardíaca.Métodos: O protocolo do estudo foi aprovado na Universidade Federal de Goiás pelo Comitê
de Ética em Pesquisa. Vinte e quatro suínos da raça Landrace foram divididos em 4 grupos:
I: após parada cardíaca, o fígado foi captado e transplantado; II: após o PC, promoveu-se a
parada cardíaca, seguida de captação e transplante hepático; III: após o PC, promoveu-se a
parada cardíaca, seguida de um período de 15 minutos de isquemia normotérmica, com
captação e transplante hepático em seguida; IV: após o PC, promoveu-se a parada cardíaca,
seguida de um período de 30 minutos de isquemia normotérmica, com captação e transplante
hepático em seguida. Nos doadores, a parada cardíaca foi obtida pela ligadura das artérias
coronárias e interrupção do suporte ventilatório. O PC (10 'x 10') e o tempo de isquemia
normotérmica foram observados em conformidade com a padronização. O fígado foi
perfundido com solução HTK resfriada a 4 ° C e posteriormente captado. Para o receptor foi
utilizada a técnica padrão. Após uma hora de reperfusão, amostras de sangue e de tecido
hepático foram coletadas, seguida da realização da eutanásia. Foram aplicados testes
estatísticos não-paramétricos. Os resultados foram expressos em medianas. O valor de p
<0,05 foi considerado estatisticamente significativo.
Resultados: Os valores encontrados de AST, ALT, lactato e fator V foram semelhantes para
os diferentes grupos estudados até o fim do experimento. No entanto, foi observado uma
tendência para piora da função hepática no grupo IV. Em relação às variáveis histológicas, a
vacuolização dos hepatócitos e a desestruturação celular foram semelhantes em todos os
grupos; houve uma tendência de aumento da congestão no grupo IV, sem significância
estatística.
Conclusões: O pré-condicionamento isquêmico remoto não mostrou benefício para enxertos
de fígado de parada cardíaca. Mesmo que o PC não tenha promovido benefícios nesta pesquisa,
também não foram observados danos.
|
4 |
The Role of Death in The Moral Permissibility of Solid Organ Procurement After Cardiac Death and Its ImplicationsLevin, Noah Michael 25 November 2013 (has links)
No description available.
|
5 |
Transplantation von Lebern nicht-herzschlagender Spender im Schweineleber-TransplantationsmodellSchön, Michael R. 14 November 2000 (has links)
Es wurde untersucht ob die normotherme extrakorporale Leberperfusion (NELP) als Methode geeignet ist, Lebern vor Transplantation zu konservieren, und ob sie warm ischämische Zellschäden beheben kann. Zum ersten Mal konnte experimentell gezeigt werden, daß eine erfolgreiche Transplantation nach 4 Stunden mit NELP möglich ist und sogar so zuverlässig, wie die Kaltkonservierung in der University of Wisconsin Lösung. Die NELP erhält die Leberfunktion und ermöglicht eine Regeneration warm ischämischer Schäden in Nicht-herzschlagenden Spendern. 36 Schweine der Deutschen Landrasse wurden in sechs Gruppen transplantiert. In der Gruppe 1 wurde direkt nach Organentnahme transplantiert, in Gruppe 2 nach 4 Stun-den Kaltkonservierung in der University of Wisconsin Lösung und in Gruppe 3 nach 4 Stunden NELP. In Gruppe 4 wurden die Lebern nach 60 Minuten warmer Ischämie direkt transplantiert, in Gruppe 5 nach 60 Minuten warmer Ischämie und 4 Stunden Kaltkonservierung und in Gruppe 6 nach 60 Minuten warmer Ischämie und 4 Stunden NELP. Alle Tiere deren Lebern vor Transplantation normotherm extrakorporal perfun-diert wurden (Gruppen 3 und 6) überlebten mit guter Organfunktion. Im Unterschied hierzu führte die Abfolge von 60 Minuten warmer Ischämie und 4 Stunden Kaltkonser-vierung unweigerlich zur primären Organ-Nichtfunktion innerhalb der ersten 24 Stun-den nach Lebertransplantation. Die Methode der NELP bietet die Chance eine Leber außerhalb des Körpers für Zeiträume von möglicherweise länger als 4 Stunden völlig funktionsfähig zu halten. Die NELP kann zur Organkonservierung vor Transplantation eingesetzt werden, aber auch dazu, Lebern von Nicht-Herzschlagenden Spendern zu nutzen. / Normothermic extracorporeal liver perfusion (NELP) was studied as a means to pre-serve livers for transplantation and to reverse warm ischemic injury. For the first time we provide experimental evidence that successful transplantation after 4h of normo-thermic extracorporeal liver perfusion is possible and as reliable as 4h of cold preser-vation in University of Wisconsin solution. NELP preserves liver function completely and is capable of reversing 60 min of warm ischemic injury in non heart beating do-nors. 36 German Landrace pigs were transplanted in six groups. Group 1 animals were transplanted directly, group 2 animals after 4h of cold preservation with University of Wisconsin solution and group 3 animals following 4h of normothermic extracorporeal liver perfusion. Group 4 animals sustained 1h of warm ischemia before transplantation of the liver. In group 5 animals were transplanted following 1h of warm ischemia and 4h of cold preservation, and in group 6 after 1h of warm ischemia and 4h of normo-thermic extracorporeal liver perfusion. All animals receiving livers treated by normo-thermic extracorporeal liver perfusion survived without liver failure (group 3 and 6). In contrast, all animals in group 5 developed primary graft non-function within 24 h after transplantation. The technique of NELP holds the potential to keep a mammalian liver outside the body completely functional, possibly for longer than 4h. NELP can be used for liver preservation prior to transplantation or to utilise organs from non-heart-beating donors.
|
Page generated in 0.087 seconds