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1.
Photodiagnosis Photodyn Ther ; 35: 102453, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303031

RESUMO

PURPOSE: To investigate the visual prognosis of patients with polypoidal choroidal vasculopathy (PCV) with a 5-year remission after an initial combination therapy involving photodynamic therapy (PDT) and intravitreal ranibizumab (IVR) or aflibercept injection (IVA). METHODS: Medical records of 69 consecutive patients with PCV treated with PDT with IVR/IVA were retrospectively reviewed, and 17 eyes were identified with a 5-year remission after the initial combination therapy. The eyes that did not require additional treatment during the 1st-5th year were assigned to the remission group and the eyes requiring additional treatment during the 1st-5th year were assigned to the recurrence group. RESULTS: During the 7-year follow-up, the mean logarithm of the minimal angle resolution best-corrected visual acuity (logMAR BCVA) significantly improved from 0.39±0.27 to 0.17±0.38 (p=2.9 × 10-4) in the remission group, whereas the mean logMAR BCVA was maintained throughout the follow-up period (0.58±0.27 to 0.60±0.48) in the recurrence group. In the remission group, only two (11.8%) of the 17 eyes experienced recurrence during the 5th-7th year. Comparison of baseline characteristics between the two groups revealed that a higher proportion of female (p=0.012), better baseline BCVA (p=3.1 × 10-3), and lower risk allele frequency in ARMS2 A69S (p=0.029) were observed in the remission group. CONCLUSIONS: The combination therapy showed a favourable outcome for PCV over a 7-year follow-up, especially in the eyes without recurrence during the 1st-5th year. Physicians should be careful of recurrent exudation in the eyes without recurrence during the 1st-5th years, although the recurrence rate was low.


Assuntos
Doenças da Coroide , Fotoquimioterapia , Inibidores da Angiogênese/uso terapêutico , Doenças da Coroide/diagnóstico , Doenças da Coroide/tratamento farmacológico , Feminino , Angiofluoresceinografia , Seguimentos , Humanos , Injeções Intravítreas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Prognóstico , Ranibizumab/uso terapêutico , Estudos Retrospectivos , Acuidade Visual
2.
Methods Mol Biol ; 2320: 151-160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34302656

RESUMO

Human-induced pluripotent stem cell (iPSC) technology paves the way for next-generation drug-safety assessment. In particular, human iPSC-derived cardiomyocytes, which exhibit electrical activity, are useful as a human cell model for assessing QT-interval prolongation and the risk of the lethal arrhythmia Torsade de Pointes (TdP). In addition to proarrhythmia assay, contractile behavior has received increased attention in drug development. In this study, we developed a novel high-throughput in vitro assay system using motion vectors to evaluate the contractile activity of iPSC-derived cardiomyocytes as a physiologically relevant human platform. The methods presented here highlight the use of commercially available iPSC-derived cardiomyocytes, iCell cardiomyocytes, for contractility evaluation recorded by the motion vector system.


Assuntos
Bioensaio/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Arritmias Cardíacas/terapia , Células Cultivadas , Humanos , Síndrome do QT Longo/terapia , Torsades de Pointes/terapia
3.
J Physiol Sci ; 71(1): 17, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078262

RESUMO

We studied the impact of mechanically regulated, expiratory negative airway pressure (ENAP) ventilation on pulmonary and systemic circulation including its mechanisms and potential applications. Microminipigs weighing about 10 kg were anesthetized (n = 5). First, hemodynamic variables were evaluated without and with ENAP to approximately -16 cmH2O. ENAP significantly increased heart rate and cardiac output, but decreased right atrial, pulmonary arterial and pulmonary capillary wedge pressures. Second, the evaluation was repeated following pharmacological adrenergic blockade, modestly blunting ENAP effects. Third, fluvoxamine (10 mg/kg) was intravenously administered to intentionally induce cardiovascular collapse in the presence of adrenergic blockade. ENAP was started when systolic pressure was < 40 mmHg in the animals assigned to ENAP treatment-group. Fluvoxamine induced cardiovascular collapse within 4 out of 5 animals. ENAP increased systolic pressure to > 50 mmHg (n = 2): both animals fully recovered without neurological deficit, whereas without ENAP both animals died of cardiac arrest (n = 2). ENAP may become an innovative treatment for drug-induced cardiovascular collapse.

4.
Int J Mol Sci ; 22(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920794

RESUMO

Few studies report drusenoid pigment epithelial detachment (DPED) in Asians. In this multicenter study, we report the clinical and genetic characteristics of 76 patients with DPED, and, for comparison, 861 patients with exudative age-related macular degeneration (AMD) were included. On the initial presentation, the mean best-corrected visual acuity was 0.087 ± 0.17 (logMAR unit), and mean DPED height and width were 210 ± 132 and 1633 ± 1114 µm, respectively. Fifty-one (67%) patients showed macular neovascularization in the contralateral eye. The risk allele frequency of both ARMS2 A69S and CFH I62V was significantly higher in DPED than in typical AMD and polypoidal choroidal vasculopathy (PCV) (ARMS2 A69S risk allele frequency: DPED 77% vs. typical AMD 66% vs. PCV 57%, CFH I62V risk allele frequency: DPED 87% vs. typical AMD 73% vs. PCV 73%), although the risk allele frequency of both genes was similar between the DPED group and retinal angiomatous proliferation (RAP) group (ARMS2 A69S: p = 0.32, CFH I62V, p = 0.11). The prevalence of reticular pseudodrusen (RPD) was highest in RAP (60%), followed by DPED (22%), typical AMD (20%), and PCV (2%). Although the prevalence of RPD differs between DPED and RAP, these entities share a similar genetic background in terms of ARMS2 and CFH genes.


Assuntos
Descolamento Retiniano/genética , Descolamento Retiniano/patologia , Drusas Retinianas/genética , Drusas Retinianas/patologia , Epitélio Pigmentado da Retina/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Degeneração Macular/genética , Degeneração Macular/patologia , Masculino
5.
J Clin Med ; 10(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807964

RESUMO

We investigated the long-term visual and anatomical outcomes of aflibercept monotherapy for exudative age-related macular degeneration (AMD) with good baseline best-corrected visual acuity (BCVA). A medical chart review was performed for 40 consecutive patients with baseline decimal BCVA ≥ 0.6 secondary to exudative AMD. Three monthly injections were administrated, and thereafter additional injection was performed if needed over 5 years. In total, 13 eyes with neovascular AMD (nAMD) and 27 eyes with polypoidal choroidal vasculopathy (PCV) were enrolled. In both groups, the mean BCVA significantly improved at the 12-month visit (p < 0.05). However, the significant improvement in BCVA disappeared at the 24-month visit, and the final mean BCVA was equivalent to that at baseline (p = 0.17 in the nAMD group and p = 0.15 in the PCV group). The median number of injections required after the loading dose was 15.0 during the 5-year follow-up (nAMD:15.0 vs. PCV:15). During the study period, 37 (92.5%) eyes required retreatment(s). Cox regression analysis demonstrated that the protective allele of ARMS2 A69S was associated with a retreatment-free period from the initial injection (p = 0.041, repeated forward selection method). As-needed aflibercept monotherapy is a preferable treatment option for exudative AMD with good initial visual acuity regardless of nAMD or PCV during the 5-year study period.

6.
Circ J ; 85(10): 1885-1891, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762525

RESUMO

BACKGROUND: Effects of rapid electrical defibrillation and ß-blockade on coronary ischemia/reperfusion-induced ventricular fibrillation (VF) during cardiopulmonary resuscitation (CPR) remain unknown.Methods and Results:After induction of VF by 30 min of ischemia followed by reperfusion, animals were treated with defibrillation alone (Group A, n=13), 2 min of open-chest cardiac massage followed by defibrillation (Group B, n=11), or the same therapy to Group B with propranolol (1 mg/kg, i.v.) treatment before ischemia/reperfusion (Group C, n=11). If return of spontaneous circulation (ROSC) was not attained, each therapy was repeated ≤3 times (Set-1). When ROSC was not obtained within Set-1, cardiac massage was applied to all animals followed by defibrillation, which was repeated ≤3 times (Set-2). ROSC after Set-1 was 8% in Group A, 82% in Group B and 82% in Group C, whereas that after Set-2 was 62% in Group A, 100% in Group B and 82% in Group C. Each animal with ROSC in Groups A (n=8) and B (n=11) showed sinus rhythm, whereas those in Group C (n=9) had sinus rhythm (n=5), atrial fibrillation (n=1), accelerated idioventricular rhythm (n=2) and atrioventricular block (n=1). Post ROSC heart rate and mean arterial pressure were significantly lower in Group C. CONCLUSIONS: Cardiac massage increased the likelihood of ROSC vs. rapid defibrillation, but ß-blocker pretreatment may worsen hemodynamics and electrical stability after ROSC.

7.
Heart Vessels ; 36(7): 1088-1097, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33763729

RESUMO

To characterize in vivo anti-atrial fibrillatory potential and pharmacological safety profile of ranolazine having INa,L plus IKr inhibitory actions in comparison with those of clinically available anti-atrial fibrillatory drugs; namely, dronedarone, amiodarone, bepridil and dl-sotalol in our previous studies, ranolazine dihydrochloride in sub-therapeutic (0.3 mg/kg) and supra-therapeutic (3 mg/kg) doses was intravenously infused over 10 min to the halothane-anesthetized dogs (n = 5). The low dose increased the heart rate, cardiac output and atrioventricular conduction velocity possibly via vasodilator action-induced, reflex-mediated increase of adrenergic tone. Meanwhile, the high dose decreased the heart rate, ventricular contraction, cardiac output and mean blood pressure, indicating that drug-induced direct actions may exceed the reflex-mediated compensation. In addition, it prolonged the atrial and ventricular effective refractory periods, of which potency and selectivity for the former were less great compared with those of the clinically-available drugs. Moreover, it did not alter the ventricular early repolarization period in vivo, but prolonged the late repolarization with minimal risk for re-entrant arrhythmias. These in vivo findings of ranolazine suggest that INa,L suppression may attenuate IKr inhibition-associated prolongation of early repolarization in the presence of reflex-mediated increase of adrenergic tone. Thus, ranolazine alone may be less promising as an anti-atrial fibrillatory drug, but its potential risk for inducing torsade de pointes will be small. These information can be used as a guide to predict the utility and adverse effects of anti-atrial fibrillatory drugs having multi-channel modulatory action.

8.
Toxicol Sci ; 181(1): 125-133, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33544870

RESUMO

In order to bridge the gap of information between the in silico model and human subjects, we evaluated torsadogenic risk of cisapride, dl-sotalol, bepridil and verapamil selected from 12 training compounds in the comprehensive in vitro proarrhythmia assay using the chronic atrioventricular block monkeys. Cisapride (0, 1, and 5 mg/kg, n = 5 for each dose), dl-sotalol (0, 1, 3, and 10 mg/kg, n = 5 for each dose), bepridil (0, 10, and 100 mg/kg, n = 4 for each dose), verapamil (0, 1.5, 15, and 75 mg/kg, n = 4 for each dose) were orally administered to the monkeys in conscious state. Five mg/kg of cisapride, 1, 3, and 10 mg/kg of dl-sotalol and 100 mg/kg of bepridil prolonged ΔΔQTcF, which was not observed by verapamil. Torsade de pointes was induced by 5 mg/kg of cisapride in 2 out of 5 animals, by 10 mg/kg of dl-sotalol in 5 out of 5 and by 100 mg/kg of bepridil in 2 out of 4, which was not induced by verapamil. These torsadogenic doses were normalized by their maximum clinical daily ones to estimate torsadogenic risk. The order of risk was dl-sotalol >bepridil ≥cisapride >verapamil in our study. Since the order was bepridil ≥dl-sotalol >cisapride >verapamil in comprehensive in vitro proarrhythmia assay (CiPA) in silico mechanistic model validation, sympathetic regulation on the heart may play a pivotal role in the onset of torsade de pointes in vivo.


Assuntos
Bloqueio Atrioventricular , Torsades de Pointes , Animais , Bepridil , Cisaprida/toxicidade , Simulação por Computador , Macaca fascicularis , Sotalol/toxicidade , Torsades de Pointes/induzido quimicamente , Verapamil/toxicidade
9.
J Pharmacol Sci ; 145(3): 268-272, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33602507

RESUMO

We assessed concentration-dependent effects of halothane or isoflurane inhalation on the electrocardiographic and hemodynamic variables using a cross-over design in intact beagle dogs (n = 4). Elevation of inhaled halothane from 1.0% to 2.0% or isoflurane from 1.5% to 2.5% decreased the mean blood pressure and prolonged the QRS width without significantly altering the heart rate, PR interval or QT interval. However, the observed changes disappeared after regressions of both anesthetic conditions to their initial settings. These results indicate that hypotension-induced, reflex-mediated increase of sympathetic tone may have counterbalanced the direct negative chronotropic, dromotropic and repolarization slowing effects of the anesthetics.


Assuntos
Anestésicos/farmacologia , Eletrocardiografia/efeitos dos fármacos , Halotano/administração & dosagem , Halotano/farmacologia , Hemodinâmica/efeitos dos fármacos , Isoflurano/administração & dosagem , Isoflurano/farmacologia , Administração por Inalação , Animais , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Cães , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Masculino , Sistema Nervoso Simpático/efeitos dos fármacos
10.
Naunyn Schmiedebergs Arch Pharmacol ; 394(6): 1103-1112, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33427928

RESUMO

Poyendarone, a deuterated analogue of dronedarone, is expected to reduce the onset of cardiovascular adverse events of dronedarone, including congestive heart failure and excessive QT-interval prolongation. Since information is still lacking on the anti-atrial fibrillatory property of poyendarone, we assessed it along with effects on the inter-atrial conduction time (IACT) and atrial effective refractory period (AERP) using the canine paroxysmal atrial fibrillation model. Poyendarone hydrochloride (n = 4) and dronedarone hydrochloride (n = 4) in intravenous doses of 0.3 and 3 mg/kg/30 s were cumulatively administered. Poyendarone hardly altered sinoatrial rate, but dronedarone decreased it in a dose-related manner, whereas both drugs slightly but significantly reduced idioventricular rate. Poyendarone shortened duration of burst pacing-induced atrial fibrillation, whereas such abbreviation was not observed by dronedarone. Poyendarone and dronedarone similarly prolonged IACT in a frequency-dependent manner, indicating that their INa inhibitory actions may be similar. The high dose of poyendarone prolonged AERP in a reverse frequency-dependent manner, extent of which at basic pacing cycle lengths of 300 and 400 ms was comparable to that of dronedarone. However, the extent at a basic pacing cycle length of 200 ms was tended to be greater in poyendarone than in dronedarone, suggesting greater IKs inhibitory action of poyendarone. The deuteration of dronedarone attenuated the inhibition of sinus automaticity and prolonged the AERP with keeping the blood pressure and ventricular rate stable. Thus, poyendarone may have both more potent anti-atrial fibrillatory action and wider cardiovascular safety margin than dronedarone.

11.
Heart Vessels ; 36(3): 424-429, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33136260

RESUMO

Lamotrigine has been used for patients with epilepsy and/or bipolar disorder, overdose of which induced the hypotension, elevation of the atrial pacing threshold, cardiac conduction delay, wide complex tachycardia, cardiac arrest and Brugada-like electrocardiographic pattern. To clarify how lamotrigine induces those cardiovascular adverse events, we simultaneously assessed its cardiohemodynamic and electrophysiological effects using the halothane-anesthetized dogs (n = 4). Lamotrigine was intravenously administered in doses of 0.1, 1 and 10 mg/kg/10 min under the monitoring of cardiovascular variables, possibly providing subtherapeutic to supratherapeutic plasma concentrations. The low or middle dose of lamotrigine did not alter any of the variables. The high dose significantly delayed the intra-atrial and intra-ventricular conductions in addition to the prolongation of ventricular effective refractory period, whereas no significant change was detected in the other variables. Lamotrigine by itself has relatively wide safety margin for cardiohemodynamics, indicating that clinically reported hypotension may not be induced through its direct action on the resistance arterioles or capacitance venules. The electrophysiological effects suggested that lamotrigine can inhibit Na+ channel in the in situ hearts. This finding may partly explain the onset mechanism of lamotrigine-associated cardiac adverse events in the clinical cases. In addition, elevation of J wave was induced in half of the animals, suggesting that lamotrigine may have some potential to unmask Brugada electrocardiographic genotype in susceptible patients.

12.
Cardiovasc Toxicol ; 21(3): 206-215, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33074476

RESUMO

While vanoxerine (GBR-12909) is a synaptosomal dopamine uptake inhibitor, it also suppresses IKr, INa and ICa,L in vitro. Based on these profiles on ionic currents, vanoxerine has been developed as a candidate compound for treating atrial fibrillation. To investigate electropharmacological profiles, vanoxerine dihydrochloride was intravenously administered at 0.03 and 0.3 mg/kg to halothane-anesthetized dogs (n = 4), possibly providing subtherapeutic and therapeutic concentrations, respectively. The low dose increased the heart rate and cardiac output, whereas it prolonged the ventricular refractoriness. The high dose decreased the heart rate but increased the total peripheral vascular resistance, whereas it delayed the ventricular repolarization and increased the atrial refractoriness in addition to further enhancing the ventricular refractoriness. The extent of increase in the refractoriness in the atrium was 0.8 times of that in the ventricle. The high dose also prolonged the early and late repolarization periods of the ventricle as well as the terminal repolarization period. Meanwhile, no significant change was detected in the mean blood pressure, ventricular contraction, preload to the left ventricle, or the intra-atrial, intra-ventricular or atrioventricular conductions. The high dose can be considered to inhibit IKr, but it may not suppress INa or ICa in the in situ heart, partly explaining its poor atrial selectivity for increasing refractoriness. The prolongation of early repolarization period may reflect enhancement of net inward current, providing potential risk for intracellular Ca2+ overload. Thus, vanoxerine may provide both trigger and substrate toward torsade de pointes, which would make the drug less promising as an anti-atrial fibrillatory drug.

13.
Naunyn Schmiedebergs Arch Pharmacol ; 394(4): 581-589, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33064166

RESUMO

Donepezil, an inhibitor for acetylcholinesterase used for patients with Alzheimer's disease, has been shown to inhibit IKr, occasionally inducing torsade de pointes. In order to analyze the causal relationship between donepezil treatment and onset of lethal arrhythmias, we initially assessed electropharmacological effects of donepezil hydrochloride of 0.01, 0.1, and 1 mg/kg, i.v. over 10 min using the halothane-anesthetized intact dogs (n = 4), possibly providing subtherapeutic to supratherapeutic plasma concentrations. Although the low or middle dose did not exert any effect, the high dose transiently increased the ventricular refractoriness along with modest prolongation of the late repolarization period, indicating potential IKr inhibitory action in vivo. Moreover, the high dose induced the positive chronotropic, inotropic, and dromotropic actions along with the pressor effect and prolongation of early repolarization period, suggesting sympathicotonic condition in the central nervous system. Next, we examined proarrhythmic effects of donepezil hydrochloride of 0.1 and 1 mg/kg, i.v. over 10 min using the conscious chronic atrioventricular block dogs (n = 4). Although the low dose hardly affected the cardiovascular variables, the high dose increased the atrial and ventricular rate without significantly altering the repolarization period, possibly reflecting sympathicotonic condition. Importantly, the high dose induced non-sustained ventricular tachycardia in half of the animals. Thus, donepezil by itself did not induce torsade de pointes in vivo, which suggests that donepezil-induced sympathicotonic condition may induce Ca2+ overload, triggering the ventricular arrhythmias, but might indirectly attenuate its IKr inhibitory action, preventing excessive repolarization delay.

14.
J Pharmacol Sci ; 145(1): 16-22, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357775

RESUMO

We compared dl-sotalol-induced electrocardiographic responses in intact dogs using a repeated-measures design among 1% halothane anesthesia, 1.5% isoflurane anesthesia with nitrous oxide (N2O), and conscious state to clarify influences of the anesthetics (n = 4). Basal PR interval was longer in halothane than either in isoflurane with N2O or in conscious state, reflecting sympathetic nerve suppression for the atrioventricular node by halothane. Both anesthetics exhibited longer basal QRS width than conscious state, suggesting their ventricular INa inhibition. Also, both anesthetics showed longer basal QT interval, QTcF and Tpeak-Tend than conscious state, indicating their ventricular IKr inhibition. Meanwhile, dl-sotalol prolonged PR interval similarly in isoflurane with N2O and in conscious state, which was less great in halothane, suggesting further sympathetic nerve suppression for the atrioventricular node might be limited in halothane. dl-Sotalol prolonged QT interval and QTcF >3 times greater in either of the anesthetics than in conscious state; moreover, dl-sotalol prolonged Tpeak-Tend similarly in both anesthetics, but hardly altered it in conscious state; indicating isoflurane with N2O as well as halothane may have reduced the repolarization reserve to increase the sensitivity of ventricle toward IKr suppression. Thus, isoflurane with nitrous oxide could be useful for in vivo IKr assay like halothane.


Assuntos
Anestesia/métodos , Estado de Consciência/efeitos dos fármacos , Eletrocardiografia/efeitos dos fármacos , Halotano , Isoflurano , Óxido Nitroso , Sotalol/farmacologia , Animais , Estado de Consciência/fisiologia , Cães , Halotano/farmacologia , Isoflurano/farmacologia , Masculino , Óxido Nitroso/farmacologia
15.
J Phys Chem B ; 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33347294

RESUMO

Following the analysis of the self-organization of two-dimensional (2D) nuclei in Part 1, the flow-mode transition from laminar magnetohydrodynamics (MHD) flow to convection cells accompanied by 2D nucleation under a uniform parallel magnetic field was theoretically examined using the statistical mechanics of nonequilibrium fluctuation. As a result, it was clarified that secondary nodules of 2D nuclei develop with multiple nucleations during the transition, forming a one-upon-another structure. Then, the evolution of the convection cells as well as the secondary nodules requires unstable growth of the asymmetrical fluctuations by the specific adsorption of an ion. As predicted by the theory, the electrolytic current in copper deposition with specific adsorption of hydrogen ions under a parallel magnetic field developed with time, resulting in a nonlinear steplike curve in a 1200 s deposition time.

16.
Sci Rep ; 10(1): 20072, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208775

RESUMO

In order to establish the universality of the excess heat production in electrochemical reaction, under a high magnetic field, as one of the most fundamental electrochemical reactions, the case of ferricyanide-ferrocyanide redox reaction was examined, where ionic vacancies with ± 1 unit charge were collided by means of magnetohydrodynamic (MHD) flow. As a result, from the pair annihilation of the vacancies with opposite signs, beyond 7 T, excess heat production up to 25 kJ·mol-1 in average at 15 T was observed, which was attributed to the liberation of the solvation energy stored in a pair of the vacancy cores with a 0.32 nm radius, i.e., 112 kJ·mol-1. Difference between the observed and expected energies comes from the small collision efficiency of 0.22 due to small radius of the vacancy core. Ionic vacancy initially created as a by-product of electrode reaction is unstable in solution phase, stabilized by releasing solvation energy. Ionic vacancy utilizes the energy to enlarge the core and stores the energy in it. As a result, solvated ionic vacancy consists of a polarized free space of the enlarged core surrounded by oppositely charged ionic cloud. The accuracy and precision of the measured values were ascertained by in situ standard additive method.

17.
Front Cell Dev Biol ; 8: 542562, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33015053

RESUMO

Contractility of the human heart increases as its beating rate is elevated, so-called positive force-frequency relationship; however, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been reported to exert a negative force-frequency relationship. We tested the hypothesis that the regulation of motion directions by electrical pacing and/or oxygen supply may improve the electro-mechanical properties of hiPSC-CMs monolayers. To better evaluate the spatial and temporal relationship between electrical excitation and contractile motion, we simultaneously observed the field potential and motion vector of hiPSC-CMs sheets. Under spontaneous contraction, although an electrical excitation originating from a region propagated unidirectionally over the cell sheet, contraction wave started from multiple sites, and relaxation wave was initiated from a geometric center of hiPSC-CMs sheet. During electrical pacing, contraction and relaxation waves were propagated from the stimulated site. Interestingly, the maximum contraction speed was more increased when the hiPSC-CMs sheet was stimulated at an area relaxation initiated under spontaneous condition. Furthermore, motion vector analysis demonstrated that "positive contraction velocity-frequency relationship" in contraction and "frequency-dependent enhancement of relaxation" were produced in the cell sheet by optimizing the direction and order of the contractile motion with pacing at the relaxation-initiating area. A close analysis of motion vectors along with field potential recording demonstrated that relaxation process consists of fast and slow phases, and suggest that intracellular Ca2+ dynamics may be closely related to functions of Ca2+-ATPase pump and Na+-Ca2+ exchangers. Namely, the slow relaxation phase occurred after the second peak of field potential, suggesting that the slow phase may be associated with extrusion of Ca2+ by Na+-Ca2+ exchangers during repolarization. Increase of oxygen concentration from 20 to 95% as well as ß-adrenergic stimulation with isoproterenol accelerated the fast relaxation, suggesting that it could depend on Ca2+ uptake via Ca2+-ATPase during the depolarization phase. The ratio of maximum contraction speed to field potential duration was increased by the ß-adrenergic stimulation, indicating the elevated contraction efficiency per Ca2+-influx. Thus, these findings revealed potential ability of conventional monolayers of hiPSC-CMs, which will help apply them to translational study filling the gap between physiological as well as pharmacological studies and clinical practice.

18.
Pharmaceuticals (Basel) ; 13(9)2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962278

RESUMO

We investigated whether polygenic risk score (PRS) was associated with one-year outcome of as-needed aflibercept therapy for exudative age-related macular degeneration (AMD), including AMD (n = 129) and polypoidal choroidal vasculopathy (n = 132). A total of 261 patients were treated with as-needed intravitreal aflibercept injection (IAI) after three monthly IAIs and the completion of a one-year follow-up. One hundred and seventy-two healthy volunteers served as controls. Genotyping of ARMS2 A69S (rs10490924), CFH I62V (rs800292), SKIV2L-C2-CFB (rs429608), C3 (rs2241394), ADAMTS-9 (rs6795735) and CETP (rs3764261) was performed for all participants. A total of 63 PRSs were quantified. There was a positive association between the PRS involving ARMS2, CFH, C3, and ADAMTS-9 and best-corrected visual acuity at twelve months (p = 0.046, multiple regression analysis). When comparing PRSs of patients requiring retreatment and of patients without retreatment, 35 PRSs were significantly greater in patients requiring retreatment than in patients without requiring retreatment, with the PRS involving ARMS2 and CFH being most significantly associated (p = 1.6 × 10-4). The number of additional injections was significantly associated with 40 PRSs and the PRS involving ARMS2 and CFH showed a most significant p-value (p = 2.42 × 10-6). Constructing a PRS using a combination with high-risk variants might be informative for predicting the response to IAI for exudative AMD.

19.
PLoS One ; 15(8): e0237330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780752

RESUMO

We investigated whether response to photodynamic therapy (PDT) with intravitreal aflibercept injection (IAI) for polypoidal choroidal vasculopathy (PCV) differs depending on fellow eye condition. A retrospective review was conducted for consecutive 60 eyes with PCV treated with PDT combined with IAI as well as 2-years of follow-up data. Fellow eyes were divided into 4 groups; Group 0: no drusen, Group 1; pachydrusen, Group 2; soft drusen, Group 3: PCV/fibrovascular scarring. Best-corrected visual acuity improved at 24-months irrespective of groups and there were no significant differences in visual improvement among treated eyes among the 4 groups. Within 2-years, 35 (58.3%) required the retreatment. The need for retreatment including additional injection and the combination therapy was significantly less in Group 1(12.5%) compared to the others (P = 0.0038) and mean number of additional IAI was also less in Group 1 compared to the others (P = 0.017). The retreatment-free period from the initial combination therapy was longest in Group 1 (23.6±1.1 months) (P = 0.0055, Group 0: 19.1±6.9, Group 2: 12.8±7.9, Group 3: 11.5±9.9). The need for retreatment was significantly different according to fellow-eye condition. Among PCV patients, pachydrusen in fellow eyes appear to be a predictive characteristic for a decreased treatment burden at 2 years.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neovascularização de Coroide/tratamento farmacológico , Fotoquimioterapia/métodos , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Drusas Retinianas/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Corioide/irrigação sanguínea , Corioide/diagnóstico por imagem , Corioide/efeitos dos fármacos , Neovascularização de Coroide/diagnóstico , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Drusas Retinianas/diagnóstico , Retratamento/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual
20.
J Clin Med ; 9(8)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32752023

RESUMO

We investigated whether responses to as-needed intravitreal aflibercept injections (IAIs) for polypoidal choroidal vasculopathy (PCV) differed among patients based upon drusen characteristics in fellow eyes. 110 eyes from 110 patients with PCV received 3 monthly IAI and thereafter Pro re nata (PRN) IAI over 12 months. Patients were classified into 4 groups depending on fellow eye findings. Group 1 (n = 16): pachydrusen; Group 2 (n = 45): no drusen; Group 3 (n = 35): soft drusen; Group4 (n = 14) PCV/scarring. Best-corrected visual acuity improved at 12 months in all groups, but not significantly in Group 1 and Group 4; however, visual improvement was similar among the groups after adjusting baseline confounders. Group 1 had a significantly lower percentage of eyes needing retreatment (all p < 0.001; Group 1: 16.7%; Group 2: 50.8%; Group 3: 80%; Group 4: 85.7%). The mean number of retreatments was least in Group 1 among the groups (all p-value < 0.003; Group 1: 0.50 ± 1.32; Group 2: 1.73 ± 2.08; Group 3:2.71 ± 1.99; Group 3: 2.71 ± 2.16). Patients with pachydrusen in fellow eyes were less likely to require additional IAI following the loading dose and may be ideal candidates for aflibercept monotherapy in their first year.

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