Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
J Org Chem ; 88(12): 7858-7862, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-36789829

RESUMO

The catalytic enantioselective hydroarylation of 1,1-disubstituted alkenes proceeded by using a cationic iridium/(R)-binap complex to give the corresponding adducts in high yields with high enantioselectivity. The reaction of arenes substituted with heteroaromatic directing groups proceeded to give the addition products linear-selectively. Methallylamine derivatives were good acceptors to obtain high enantioselectivities. The adduct bearing maleimide moiety was readily transformed into the ß-chiral amine derivative without loss of the enantiomeric purity.


Assuntos
Alcenos , Irídio , Estereoisomerismo , Aminas , Catálise
2.
J Infect Chemother ; 29(1): 15-19, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36089257

RESUMO

INTRODUCTION: Anterior nasal sampling (AN) might be more convenient for patients than NP sampling to diagnose coronavirus disease. This study investigated the feasibility of rapid antigen tests for AN sampling, and the factors affecting the test accuracy. METHODS: This single-center prospective study evaluated one qualitative (ESP) and two quantitative (LUMI and LUMI-P) rapid antigen tests using AN and NP swabs. Symptomatic patients aged 20 years or older, who were considered eligible for reverse-transcription quantitative polymerase chain reaction using NP samples within 9 days of onset were recruited. Sensitivity, specificity, and positive and negative concordance rates between AN and NP samples were assessed for the rapid antigen tests. We investigated the characteristics that affected the concordance between AN and NP sampling results. RESULTS: A total of 128 cases were recruited, including 28 positive samples and 96 negative samples. The sensitivity and specificity of AN samples using ESP were 0.81 and 1.00, while those of NP samples were 0.94 and 1.00. The sensitivity of AN and NP samples was 0.91 and 0.97, respectively, and specificity was 1.00, for both LUMI and LUMI-P. The positive concordance rates of AN to NP sampling were 0.87, 0.94, and 0.85 for ESP, LUMI, and LUMI-P, respectively. No factor had a significant effect on the concordance between the sampling methods. CONCLUSIONS: ESP, LUMI, and LUMI-P showed practical diagnostic accuracy for AN sampling compared to NP sampling. There was no significant factor affecting the concordance between AN and NP sampling for these rapid antigen tests.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Estudos Prospectivos , COVID-19/diagnóstico , Teste para COVID-19 , Sensibilidade e Especificidade , Nasofaringe
3.
BMC Anesthesiol ; 22(1): 191, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725372

RESUMO

BACKGROUND: Unplanned ICU admission after surgery has been validated as a measure of a quality indicator of perioperative management because it may put surgical patients at risk of increased morbidity and mortality. Postoperative unscheduled admission to the ICU is usually determined either in the post-anesthesia care unit (PACU) or in the general surgical ward; however, it could be expected patient outcomes after ICU admission would be affected by the circumstances. The purpose of this retrospective observational study was to investigate the clinical characteristics and the outcome of unplanned admission to the ICU directly from the PACU or from the ward within 7 days after PACU discharge. METHODS: Forty-three thousand, five hundred fifty-three patients admitted to the PACU after general anesthesia were included in the study. Unplanned ICU admission was defined as the admission which was not anticipated preoperatively but was due to adverse events in the PACU (PACU group) or the ward after discharge from the PACU (Ward group). The following parameters were compared between the groups: patient characteristics, surgical characteristics, length of ICU and hospital stay, the principal adverse event for ICU admission, treatments in the ICU, and in-hospital mortality. The primary outcome was in-hospital mortality and the second was the length of ICU and hospital stay. RESULTS: Among 43,553 patients, 109 patients underwent unplanned ICU admission directly from the PACU (n= 73, 0.17%) or subsequently from the ward (n= 36, 0.08%). The length of both ICU and hospital stay was significantly longer in the Ward group than in the PACU group (1.4 and 19 days vs. 2.5 and 39 days, respectively). There was no significant difference in in-hospital mortality between the groups (4.1% vs. 8.3%, respectively). CONCLUSIONS: The incidence of unplanned ICU admission after PACU stay was low, however, delayed admission to the ICU from the ward may prolong the length of both ICU and hospital stay compared to those directly from the PACU.


Assuntos
Hospitalização , Unidades de Terapia Intensiva , Anestesia Geral/efeitos adversos , Mortalidade Hospitalar , Humanos , Tempo de Internação , Estudos Retrospectivos
6.
Am J Physiol Heart Circ Physiol ; 312(3): H392-H405, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28011590

RESUMO

Cardiac sympathetic denervation (CSD) is reported to reduce the burden of ventricular tachyarrhythmias [ventricular tachycardia (VT)/ventricular fibrillation (VF)] in cardiomyopathy patients, but the mechanisms behind this benefit are unknown. In addition, the relative contribution to cardiac innervation of the middle cervical ganglion (MCG), which may contain cardiac neurons and is not removed during this procedure, is unclear. The purpose of this study was to compare sympathetic innervation of the heart via the MCG vs. stellate ganglia, assess effects of bilateral CSD on cardiac function and VT/VF, and determine changes in cardiac sympathetic innervation after CSD to elucidate mechanisms of benefit in 6 normal and 18 infarcted pigs. Electrophysiological and hemodynamic parameters were evaluated at baseline, during bilateral stellate stimulation, and during bilateral MCG stimulation in 6 normal and 12 infarcted animals. Bilateral CSD (removal of bilateral stellates and T2 ganglia) was then performed and MCG stimulation repeated. In addition, in 18 infarcted animals VT/VF inducibility was assessed before and after CSD. In infarcted hearts, MCG stimulation resulted in greater chronotropic and inotropic response than stellate ganglion stimulation. Bilateral CSD acutely reduced VT/VF inducibility by 50% in infarcted hearts and prolonged global activation recovery interval. CSD mitigated effects of MCG stimulation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts, without causing hemodynamic compromise. These data demonstrate that the MCG provides significant cardiac sympathetic innervation before CSD and adequate sympathetic innervation after CSD, maintaining hemodynamic stability. Bilateral CSD reduces VT/VF inducibility by improving electrical stability in infarcted hearts in the setting of sympathetic activation.NEW & NOTEWORTHY Sympathetic activation in myocardial infarction leads to arrhythmias and worsens heart failure. Bilateral cardiac sympathetic denervation reduces ventricular tachycardia/ventricular fibrillation inducibility and mitigates effects of sympathetic activation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts. Hemodynamic stability is maintained, as innervation via the middle cervical ganglion is not interrupted.


Assuntos
Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/cirurgia , Gânglios Simpáticos/fisiopatologia , Gânglios Simpáticos/cirurgia , Coração/inervação , Gânglio Estrelado/fisiopatologia , Gânglio Estrelado/cirurgia , Simpatectomia , Sistema Nervoso Simpático/fisiopatologia , Sistema Nervoso Simpático/cirurgia , Animais , Arritmias Cardíacas/metabolismo , Estimulação Cardíaca Artificial , Estimulação Elétrica , Frequência Cardíaca , Contração Miocárdica , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Norepinefrina/metabolismo , Suínos , Sistema Nervoso Simpático/metabolismo , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Fibrilação Ventricular/metabolismo , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/cirurgia
7.
Anesthesiology ; 126(6): 1096-1106, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28358748

RESUMO

BACKGROUND: Imbalances in the autonomic nervous system, namely, excessive sympathoexcitation, contribute to ventricular tachyarrhythmias. While thoracic epidural anesthesia clinically suppresses ventricular tachyarrhythmias, its effects on global and regional ventricular electrophysiology and electrical wave stability have not been fully characterized. The authors hypothesized that thoracic epidural anesthesia attenuates myocardial excitability and the proarrhythmic effects of sympathetic hyperactivity. METHODS: Yorkshire pigs (n = 15) had an epidural catheter inserted (T1 to T4) and a 56-electrode sock placed on the heart. Myocardial excitability was measured by activation recovery interval, dispersion of repolarization, and action potential duration restitution at baseline and during programed ventricular extrastimulation or left stellate ganglion stimulation, before and 30 min after thoracic epidural anesthesia (0.25% bupivacaine). RESULTS: After thoracic epidural anesthesia infusion, there was no change in baseline activation recovery interval or dispersion of repolarization. During programmed ventricular extrastimulation, thoracic epidural anesthesia decreased the maximum slope of ventricular electrical restitution (0.70 ± 0.24 vs. 0.89 ± 0.24; P = 0.021) reflecting improved electrical wave stability. Thoracic epidural anesthesia also reduced myocardial excitability during left stellate ganglion stimulation-induced sympathoexcitation through attenuated shortening of activation recovery interval (-7 ± 4% vs. -4 ± 3%; P = 0.001), suppression of the increase in dispersion of repolarization (313 ± 293% vs. 185 ± 234%; P = 0.029), and reduction in sympathovagal imbalance as measured by heart rate variability. CONCLUSIONS: Our study describes the electrophysiologic mechanisms underlying antiarrhythmic effects of thoracic epidural anesthesia during sympathetic hyperactivity. Thoracic epidural anesthesia attenuates ventricular myocardial excitability and induces electrical wave stability through its effects on activation recovery interval, dispersion of repolarization, and the action potential duration restitution slope.


Assuntos
Anestesia Epidural/métodos , Bupivacaína/farmacologia , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Anestésicos Locais/farmacologia , Animais , Estimulação Elétrica , Feminino , Masculino , Modelos Animais , Suínos
8.
Am J Physiol Regul Integr Comp Physiol ; 310(5): R414-21, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26661096

RESUMO

Sympathoexcitation is associated with ventricular arrhythmogenesis. The aim of this study was to determine the role of thoracic dorsal root afferent neural inputs to the spinal cord in modulating ventricular sympathetic control of normal heart electrophysiology. We hypothesize that dorsal root afferent input tonically modulates basal and evoked efferent sympathetic control of the heart. A 56-electrode sock placed on the epicardial ventricle in anesthetized Yorkshire pigs (n = 17) recorded electrophysiological function, as well as activation recovery interval (ARI) and dispersion in ARI, at baseline conditions and during stellate ganglion electrical stimulation. Measures were compared between intact states and sequential unilateral T1-T4 dorsal root transection (DRTx), ipsilateral ventral root transection (VRTx), and contralateral dorsal and ventral root transections (DVRTx). Left or right DRTx decreased global basal ARI [Lt.DRTx: 369 ± 12 to 319 ± 13 ms (P < 0.01) and Rt.DRTx: 388 ± 19 to 356 ± 15 ms (P < 0.01)]. Subsequent unilateral VRTx followed by contralateral DRx+VRTx induced no further change. In intact states, left and right stellate ganglion stimulation shortened ARIs (6 ± 2% vs. 17 ± 3%), while increasing dispersion (+139% vs. +88%). There was no difference in magnitude of ARI or dispersion change with stellate stimulation following spinal root transections. Interruption of thoracic spinal afferent signaling results in enhanced basal cardiac sympathoexcitability without diminishing the sympathetic response to stellate ganglion stimulation. This suggests spinal dorsal root transection releases spinal cord-mediated tonic inhibitory control of efferent sympathetic tone, while maintaining intrathoracic cardiocentric neural networks.


Assuntos
Frequência Cardíaca , Ventrículos do Coração/inervação , Medula Espinal/fisiologia , Raízes Nervosas Espinhais/fisiologia , Sistema Nervoso Simpático/fisiologia , Função Ventricular Esquerda , Potenciais de Ação , Animais , Arritmias Cardíacas/fisiopatologia , Estimulação Elétrica , Feminino , Laminectomia , Masculino , Modelos Animais , Inibição Neural , Neurônios Aferentes/fisiologia , Neurônios Eferentes/fisiologia , Medula Espinal/cirurgia , Raízes Nervosas Espinhais/cirurgia , Gânglio Estrelado/fisiologia , Suínos , Pressão Ventricular
9.
Am J Physiol Heart Circ Physiol ; 309(9): H1579-90, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26371172

RESUMO

Vagal nerve stimulation (VNS) has been shown to have antiarrhythmic effects, but many of these benefits were demonstrated in the setting of vagal nerve decentralization. The purpose of this study was to evaluate the role of afferent fiber activation during VNS on efferent control of cardiac hemodynamic and electrophysiological parameters. In 37 pigs a 56-electrode sock was placed over the ventricles to record local activation recovery intervals (ARIs), a surrogate of action potential duration. In 12 of 37 animals atropine was given systemically. Right and left VNS were performed under six conditions: both vagal trunks intact (n = 25), ipsilateral right (n = 11), ipsilateral left (n = 14), contralateral right (n = 7), contralateral left (n = 10), and bilateral (n = 25) vagal nerve transection (VNTx). Unilateral VNTx significantly affected heart rate, PR interval, Tau, and global ARIs. Right VNS after ipsilateral VNTx had augmented effects on hemodynamic parameters and increase in ARI, while subsequent bilateral VNTx did not significantly modify this effect (%change in ARI in intact condition 2.2 ± 0.9% vs. ipsilateral VNTx 5.3 ± 1.7% and bilateral VNTx 5.3 ± 0.8%, P < 0.05). Left VNS after left VNTx tended to increase its effects on hemodynamics and ARI response (P = 0.07), but only after bilateral VNTx did these changes reach significance (intact 1.1 ± 0.5% vs. ipsilateral VNTx 3.6 ± 0.7% and bilateral VNTx 6.6 ± 1.6%, P < 0.05 vs. intact). Contralateral VNTx did not modify VNS response. The effect of atropine on ventricular ARI was similar to bilateral VNTx. We found that VNS activates afferent fibers in the ipsilateral vagal nerve, which reflexively inhibit cardiac parasympathetic efferent electrophysiological and hemodynamic effects.


Assuntos
Potenciais de Ação/fisiologia , Vias Aferentes/fisiologia , Vias Eferentes/fisiologia , Ventrículos do Coração/inervação , Sistema Nervoso Parassimpático/fisiologia , Vagotomia , Estimulação do Nervo Vago , Nervo Vago/fisiologia , Função Ventricular/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Atropina/farmacologia , Feminino , Coração/efeitos dos fármacos , Coração/inervação , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Masculino , Sistema Nervoso Parassimpático/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Sus scrofa , Suínos , Nervo Vago/cirurgia , Função Ventricular/efeitos dos fármacos
10.
Am J Physiol Heart Circ Physiol ; 307(5): H722-31, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25015962

RESUMO

Vagal nerve stimulation (VNS) has been proposed as a cardioprotective intervention. However, regional ventricular electrophysiological effects of VNS are not well characterized. The purpose of this study was to evaluate effects of right and left VNS on electrophysiological properties of the ventricles and hemodynamic parameters. In Yorkshire pigs, a 56-electrode sock was used for epicardial (n = 12) activation recovery interval (ARI) recordings and a 64-electrode catheter for endocardial (n = 9) ARI recordings at baseline and during VNS. Hemodynamic recordings were obtained using a conductance catheter. Right and left VNS decreased heart rate (84 ± 5 to 71 ± 5 beats/min and 84 ± 4 to 73 ± 5 beats/min), left ventricular pressure (89 ± 9 to 77 ± 9 mmHg and 91 ± 9 to 83 ± 9 mmHg), and dP/dtmax (1,660 ± 154 to 1,490 ± 160 mmHg/s and 1,595 ± 155 to 1,416 ± 134 mmHg/s) and prolonged ARI (327 ± 18 to 350 ± 23 ms and 327 ± 16 to 347 ± 21 ms, P < 0.05 vs. baseline for all parameters and P = not significant for right VNS vs. left VNS). No anterior-posterior-lateral regional differences in the prolongation of ARI during right or left VNS were found. However, endocardial ARI prolonged more than epicardial ARI, and apical ARI prolonged more than basal ARI during both right and left VNS. Changes in dP/dtmax showed the strongest correlation with ventricular ARI effects (R(2) = 0.81, P < 0.0001) than either heart rate (R(2) = 0.58, P < 0.01) or left ventricular pressure (R(2) = 0.52, P < 0.05). Therefore, right and left VNS have similar effects on ventricular ARI, in contrast to sympathetic stimulation, which shows regional differences. The decrease in inotropy correlates best with ventricular electrophysiological effects.


Assuntos
Nervo Vago/fisiologia , Função Ventricular , Potenciais de Ação , Animais , Pressão Sanguínea , Endocárdio/inervação , Endocárdio/fisiologia , Frequência Cardíaca , Pericárdio/inervação , Pericárdio/fisiologia , Suínos , Estimulação do Nervo Vago/efeitos adversos
11.
J Surg Res ; 188(2): 381-6, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24525060

RESUMO

BACKGROUND: The current commonly used cardiac ischemic preconditioning (IPC) protocol, involving three 5-min cycles of ischemia-reperfusion (I/R), may not be clinically beneficial because of its acutely deleterious effects on hemodynamics. This study attempted to assess the effects of a novel stepwise IPC scheme on cardiac function, infarct size, and arrhythmogenesis in a rabbit model of prolonged I/R. METHODS: Anesthetized open-chest rabbits were subjected to 60-min occlusion of a proximal branch of the left coronary artery followed by 180-min reperfusion. Animals were divided into five groups (n = 6 each): (1) control group (no IPC); (2) 2-min IPC group (three cycles of 2-min IPC); (3) 5-min IPC group (three cycles of 5-min IPC); (4) 10-min IPC group (three cycles of 10-min IPC); and (5) stepwise IPC group (2-, 5-, and 10-min I/R). RESULTS: Compared with control group, 2-, 5-, and 10-min IPC decreased arrhythmia score by 16%, 67%, and 33%, respectively. Remarkably, stepwise IPC resulted in a 78% reduction of arrhythmias. Stepwise IPC also produced the least ventricular infarct size when compared with 2-, 5-, and 10-min IPC groups (16.4% versus 39.3%, 28.1%, and 38.5%, P < 0.05). CONCLUSIONS: These results suggest that stepwise IPC has better cardioprotective effects against prolonged I/R injury and may serve as an acceptable approach to clinical revascularization procedures on the heart, including catheter-based and surgical approaches.


Assuntos
Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Arritmias Cardíacas/patologia , Diástole , Frequência Cardíaca , Hemodinâmica , Modelos Animais , Infarto do Miocárdio/patologia , Miocárdio/patologia , Coelhos , Sístole , Função Ventricular Esquerda , Pressão Ventricular
12.
Am J Physiol Heart Circ Physiol ; 305(7): H1031-40, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23893167

RESUMO

Myocardial infarction (MI) induces neural and electrical remodeling at scar border zones. The impact of focal MI on global functional neural remodeling is not well understood. Sympathetic stimulation was performed in swine with anteroapical infarcts (MI; n = 9) and control swine (n = 9). A 56-electrode sock was placed over both ventricles to record electrograms at baseline and during left, right, and bilateral stellate ganglion stimulation. Activation recovery intervals (ARIs) were measured from electrograms. Global and regional ARI shortening, dispersion of repolarization, and activation propagation were assessed before and during sympathetic stimulation. At baseline, mean ARI was shorter in MI hearts than control hearts (365 ± 8 vs. 436 ± 9 ms, P < 0.0001), dispersion of repolarization was greater in MI versus control hearts (734 ± 123 vs. 362 ± 32 ms(2), P = 0.02), and the infarcted region in MI hearts showed longer ARIs than noninfarcted regions (406 ± 14 vs. 365 ± 8 ms, P = 0.027). In control animals, percent ARI shortening was greater on anterior than posterior walls during right stellate ganglion stimulation (P = 0.0001), whereas left stellate ganglion stimulation showed the reverse (P = 0.0003). In infarcted animals, this pattern was completely lost. In 50% of the animals studied, sympathetic stimulation, compared with baseline, significantly altered the direction of activation propagation emanating from the intramyocardial scar during pacing. In conclusion, focal distal anterior MI alters regional and global pattern of sympathetic innervation, resulting in shorter ARIs in infarcted hearts, greater repolarization dispersion, and altered activation propagation. These conditions may underlie the mechanisms by which arrhythmias are initiated when sympathetic tone is enhanced.


Assuntos
Infarto Miocárdico de Parede Anterior/complicações , Arritmias Cardíacas/etiologia , Coração/inervação , Miocárdio/patologia , Gânglio Estrelado/fisiopatologia , Animais , Infarto Miocárdico de Parede Anterior/patologia , Infarto Miocárdico de Parede Anterior/fisiopatologia , Arritmias Cardíacas/patologia , Arritmias Cardíacas/fisiopatologia , Modelos Animais de Doenças , Estimulação Elétrica , Técnicas Eletrofisiológicas Cardíacas , Suínos , Fatores de Tempo
13.
Am J Physiol Heart Circ Physiol ; 305(7): H1020-30, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23893168

RESUMO

Left stellate or right stellate ganglion stimulation (LGSG or RSGS, respectively) is associated with ventricular tachyarrhythmias; however, the electrophysiological mechanisms remain unclear. We assessed 1) regional dispersion of myocardial repolarization during RSGS and LSGS and 2) regional electrophysiological mechanisms underlying T-wave changes, including T-peak to T-end (Tp-e) interval, which are associated with ventricular tachyarrhythmia/ventricular fibrillation. In 10 pigs, a 56-electrode sock was placed around the heart, and both stellate ganglia were exposed. Unipolar electrograms, to asses activation recovery interval (ARI) and repolarization time (RT), and 12-lead ECG were recorded before and during RSGS and LSGS. Both LSGS and RSGS increased dispersion of repolarization; with LSGS, the greatest regional dispersion occurred on the left ventricular (LV) anterior wall and LV apex, whereas with RSGS, the greatest regional dispersion occurred on the right ventricular posterior wall. Baseline, LSGS, and RSGS dispersion correlated with Tp-e. The increase in RT dispersion, which was due to an increase in ARI dispersion, correlated with the increase in Tp-e intervals (R(2) = 0.92 LSGS; and R(2) = 0.96 RSGS). During LSGS, the ARIs and RTs on the lateral and posterior walls were shorter than the anterior LV wall (P < 0.01) and on the apex versus base (P < 0.05), explaining the T-wave vector shift posteriorly/inferiorly. RSGS caused greater ARI and RT shortening on anterior versus lateral or posterior walls (P < 0.01) and on base versus apex (P < 0.05), explaining the T-wave vector shift anteriorly/superiorly. LSGS and RSGS cause differential effects on regional myocardial repolarization, explaining the ECG T-wave morphology. Sympathetic stimulation, in line with its proarrhythmic effects, increases Tp-e interval, which correlates with increases in myocardial dispersion of repolarization.


Assuntos
Sistema de Condução Cardíaco/fisiopatologia , Coração/inervação , Gânglio Estrelado/fisiopatologia , Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Potenciais de Ação , Animais , Modelos Animais de Doenças , Estimulação Elétrica , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Hemodinâmica , Suínos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia , Fatores de Tempo , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/etiologia
14.
Am J Physiol Heart Circ Physiol ; 304(6): H840-7, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23335795

RESUMO

Left ventricular (LV) twist mechanics and regional strain during cardiac sympathetic efferent activation are poorly understood. The purpose of this study was to compare the effects of left stellate ganglia (LSG) and right stellate ganglia (RSG) stimulation on cardiac twist/untiwst mechanics and regional strain. In nine pigs, echocardiographic imaging and LV pressure-volume measurements were performed before and during unilateral and bilateral stellate ganglion stimulation. LSG and RSG stimulation significantly augmented LV end-systolic pressure by 24% and 22% (P < 0.01), maximal rate of LV pressure change by 167% and 165% (P < 0.01), and time constant of LV relaxation by 20% and 12% (P < 0.01), respectively. RSG stimulation resulted in a greater chronotropic response than LSG stimulation (RSG: 68% vs. LSG: 12%, P < 0.01). Both LSG and RSG stimulation significantly increased global epicardial and endocardial LV rotation and diastolic untwisting rate and reduced the time to peak rotation (P < 0.05). However, LSG stimulation predominantly increased radial and circumferential strain in the LV inferoseptal, inferior, posterior, and lateral regions, whereas RSG stimulation primarily increased radial and circumferential strain in the anteroseptal, anterior, and lateral LV regions. Stimulation of both stellate ganglia led to a uniform increase in all LV segments. Our data suggest that LSG and RSG stimulation lead to a global increase in LV twist, driven by distinct regional strain heterogeneity that may result from myocardial innervation from the LSG and RSG. These findings provide a better understanding of the global and regional functional consequences of regional myocardial innervation from the LSG and RSG.


Assuntos
Gânglio Estrelado/fisiologia , Função Ventricular Esquerda , Animais , Pressão Sanguínea , Ecocardiografia/métodos , Estimulação Elétrica , Endocárdio/fisiologia , Feminino , Frequência Cardíaca , Ventrículos do Coração/inervação , Contração Miocárdica , Pericárdio/fisiologia , Rotação , Sus scrofa
15.
Am J Physiol Heart Circ Physiol ; 304(4): H579-88, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23241324

RESUMO

Increased cardiac sympathetic activation worsens dispersion of repolarization and is proarrhythmic. The functional differences between intrinsic nerve stimulation and adrenergic receptor activation remain incompletely understood. This study was undertaken to determine the functional differences between efferent cardiac sympathetic nerve stimulation and direct adrenergic receptor activation in porcine ventricles. Female Yorkshire pigs (n = 13) underwent surgical exposure of the heart and stellate ganglia. A 56-electrode sock was placed over the ventricles to record epicardial electrograms. Animals underwent bilateral sympathetic stimulation (BSS) (n = 8) or norepinephrine (NE) administration (n = 5). Activation recovery intervals (ARIs) were measured at each electrode before and during BSS or NE. The degree of ARI shortening during BSS or NE administration was used as a measure of functional nerve or adrenergic receptor density. During BSS, ARI shortening was nonuniform across the epicardium (F value 9.62, P = 0.003), with ARI shortening greatest in the mid-basal lateral right ventricle and least in the midposterior left ventricle (LV) (mean normalized values: 0.9 ± 0.08 vs. 0.56 ± 0.08; P = 0.03). NE administration resulted in greater ARI shortening in the LV apex than basal segments [0.91 ± 0.04 vs. 0.63 ± 0.05 (averaged basal segments); P = 0.003]. Dispersion of ARIs increased in 50% and 60% of the subjects undergoing BSS and NE, respectively, but decreased in the others. There is nonuniform response to cardiac sympathetic activation of both porcine ventricles, which is not fully explained by adrenergic receptor density. Different pools of adrenergic receptors may mediate the cardiac electrophysiological effects of efferent sympathetic nerve activity and circulating catecholamines.


Assuntos
Receptores Adrenérgicos/fisiologia , Função Ventricular/fisiologia , Agonistas alfa-Adrenérgicos/administração & dosagem , Animais , Feminino , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/inervação , Norepinefrina/administração & dosagem , Pericárdio/efeitos dos fármacos , Pericárdio/fisiologia , Gânglio Estrelado/efeitos dos fármacos , Gânglio Estrelado/fisiologia , Suínos , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiologia , Função Ventricular/efeitos dos fármacos
16.
Chem Commun (Camb) ; 59(86): 12871-12874, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37817678

RESUMO

Enantioselective addition of an imide N-H bond to alkenes was realized by use of a cationic iridium catalyst. Bulky diphosphine ligands such as DTBM-segphos, DTBM-MeO-biphep, and DTBM-binap were indispensable for the reaction. A variety of styrene derivatives, allylsilanes, and norbornene were good substrates to give the corresponding chiral adducts with high enantioselectivity.

17.
JA Clin Rep ; 9(1): 23, 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37173559

RESUMO

BACKGROUND: Although intraoperative hypotension (IOH) has been emerging as a serious concern during general anesthesia, the incidence of IOH has not been demonstrated clearly in the Japanese population. METHODS: This single-center retrospective study investigated the incidence and the characteristics of IOH in non-cardiac surgery at a university hospital. IOH was defined as at least one fall of MAP during general anesthesia, which was categorized into the following groups: mild (65 to < 75 mmHg), moderate (55 to < 65 mmHg), severe (45 to < 55 mmHg), and very severe (< 45 mmHg). The incidence of IOH was calculated as a percentage of the number of events to the total anesthesia cases. Logistic regression analysis was performed to examine factors affecting IOH. RESULTS: Eleven thousand two hundred ten cases out of 13,226 adult patients were included in the analysis. We found moderate to very severe hypotension occurred in 86.3% of the patients for at least 1 to 5 min, and 48.5% experienced severe or very severe hypotension. The results of the logistic regression analysis indicated female gender, vascular surgery, American Society of Anesthesiologists physical status classification (ASA-PS) 4 or 5 in emergency surgery, and the combination with the epidural block (EDB) were significant factors of IOH. CONCLUSIONS: IOH during general anesthesia was very frequent in the Japanese population. Female gender, vascular surgery, ASA-PA 4 or 5 in emergency surgery, and the combination with EDB were independent risk factors associated with IOH. However, the association with patient outcomes were not elucidated.

18.
PLoS One ; 18(5): e0285120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37130135

RESUMO

BACKGROUND: Postoperative atrial fibrillation (POAF) increases postoperative morbidity, mortality, and length of hospital stay. Propofol is reported to modulate atrial electrophysiology and the cardiac autonomic nervous system. Therefore, we retrospectively examined whether propofol suppresses POAF in patients undergoing video-assisted thoracoscopic surgery (VATS) compared to desflurane. METHODS: We retrospectively recruited adult patients who underwent VATS during the period from January 2011 to May 2018 in an academic university hospital. Between continuous propofol and desflurane administration during anesthetic maintenance, we investigated the incidence of new-onset POAF (within 48 hours after surgery) before and after propensity score matching. RESULTS: Of the 482 patients, 344 received propofol, and 138 received desflurane during anesthetic maintenance. The incidence of POAF in the propofol group was less than that in the desflurane group (4 [1.2%] vs. 8 patients [5.8%], odds ratio [OR]; 0.161, 95% confidence interval (CI), 0.040-0.653, p = 0.011) in the present study population. After adjustment for propensity score matching (n = 254, n = 127 each group), the incidence of POAF was still less in propofol group than desflurane group (1 [0.8%] vs. 8 patients [6.3%], OR; 0.068, 95% CI: 0.007-0.626, p = 0.018). CONCLUSIONS: These retrospective data suggest propofol anesthesia significantly inhibits POAF compared to desflurane anesthesia in patients undergoing VATS. Further prospective studies are needed to elucidate the mechanism of propofol on the inhibition of POAF.


Assuntos
Anestesia , Anestésicos , Fibrilação Atrial , Propofol , Adulto , Humanos , Propofol/efeitos adversos , Desflurano , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etiologia , Fibrilação Atrial/prevenção & controle , Incidência
19.
Am J Physiol Heart Circ Physiol ; 302(9): H1818-25, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22367505

RESUMO

Augmentation of cardiac sympathetic tone during myocardial ischemia has been shown to increase myocardial O(2) demand and infarct size as well as induce arrhythmias. We have previously demonstrated that electroacupuncture (EA) inhibits the visceral sympathoexcitatory cardiovascular reflex. The purpose of this study was to determine the effects of EA on left ventricular (LV) function, O(2) demand, infarct size, arrhythmogenesis, and in vivo cardiac norepinephrine (NE) release in a myocardial ischemia-reperfusion model. Anesthetized rabbits (n = 36) underwent 30 min of left anterior descending coronary artery occlusion followed by 90 min of reperfusion. We evaluated myocardial O(2) demand, infarct size, ventricular arrhythmias, and myocardial NE release using microdialysis under the following experimental conditions: 1) untreated, 2) EA at P5-6 acupoints, 3) sham acupuncture, 4) EA with pretreatment with naloxone (a nonselective opioid receptor antagonist), 5) EA with pretreatment with chelerythrine (a nonselective PKC inhibitor), and 6) EA with pretreatment with both naloxone and chelerythrine. Compared with the untreated and sham acupuncture groups, EA resulted in decreased O(2) demand, myocardial NE concentration, and infarct size. Furthermore, the degree of ST segment elevation and severity of LV dysfunction and ventricular arrhythmias were all significantly decreased (P < 0.05). The cardioprotective effects of EA were partially blocked by pretreatment with naloxone or chelerythrine alone and completely blocked by pretreatment with both naloxone and chelerythrine. These results suggest that the cardioprotective effects of EA against myocardial ischemia-reperfusion are mediated through inhibition of the cardiac sympathetic nervous system as well as opioid and PKC-dependent pathways.


Assuntos
Eletroacupuntura , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Norepinefrina/metabolismo , Sistema Nervoso Simpático/fisiologia , Animais , Arritmias Cardíacas/prevenção & controle , Benzofenantridinas/farmacologia , Modelos Animais , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Naloxona/farmacologia , Antagonistas de Entorpecentes , Oxigênio/metabolismo , Proteína Quinase C/antagonistas & inibidores , Coelhos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Função Ventricular Esquerda/fisiologia
20.
J Anesth ; 26(4): 592-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22361908

RESUMO

A hybrid operating suite, where craniotomy, brain CT scanning, fluoroscopy, and angiography can be performed on the same operating table, is becoming popular among neurosurgeons. However, whether use of a hybrid operating suite can improve neurological outcome has not been studied. We reviewed the incidence and outcomes of ruptures of cerebral vascular lesions during interventional neuroradiology procedures performed in our hybrid operating suite. Of 602 patients who underwent coil embolization under general anesthesia, five cases of intraprocedural rupture of the aneurysms were identified. Despite emergency neurosurgical intervention within 2 h of rupture of the aneurysms, two of these five patients died and one patient had permanent neurological deficit postsurgery. Whether use of a hybrid operating suite improves neurological outcome remains uncertain.


Assuntos
Aneurisma Roto/etiologia , Embolização Terapêutica/efeitos adversos , Aneurisma Intracraniano/cirurgia , Complicações Intraoperatórias/etiologia , Doenças do Sistema Nervoso/etiologia , Neurocirurgia , Salas Cirúrgicas/organização & administração , Idoso , Anestesia Geral , Aneurisma Roto/cirurgia , Craniotomia , Evolução Fatal , Feminino , Escala de Resultado de Glasgow , Humanos , Malformações Arteriovenosas Intracranianas/cirurgia , Complicações Intraoperatórias/fisiopatologia , Complicações Intraoperatórias/cirurgia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/fisiopatologia , Procedimentos Neurocirúrgicos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa