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1.
Artículo en Inglés | MEDLINE | ID: mdl-38753535

RESUMEN

Background: - Endocardial catheter-based pulsed field ablation (PFA) of the ventricular myocardium is promising. However, little is known about PFA's ability to target intracavitary structures, epicardium, and ways to achieve transmural lesions across thick ventricular tissue. Methods:- A lattice-tip catheter was used to deliver biphasic monopolar PFA to swine ventricles under general anesthesia, with electroanatomical mapping, fluoroscopy and intracardiac echocardiography (ICE) guidance. We conducted experiments to assess the feasibility and safety of repetitive monopolar PFA applications to ablate: i) intracavitary papillary muscles and moderator bands, ii) epicardial targets, and iii) bipolar PFA for midmyocardial targets in the interventricular septum and left ventricular (LV) free wall. Results: - i) Papillary muscles (n=13) were successfully ablated and then evaluated at 2, 7 and 21 days. Nine lesions with stable contact measured 18.3≥2.4 mm long, 15.3≥1.5 mm wide, and 5.8≥1.0 mm deep at 2 days. Chronic lesions demonstrated preserved chordae without mitral regurgitation. Two targeted moderator bands were transmurally ablated without structural disruption. ii) Transatrial saline/carbon dioxide assisted epicardial access was obtained successfully and epicardial monopolar lesions had a mean length, width, and depth of 30.4≥4.2 mm, 23.5≥4.1 mm, and 9.1≥1.9 mm, respectively. iii) Bipolar PFA lesions were delivered across the septum (n=11) and the LV free wall (n=7). Twelve completed bipolar lesions had a mean length, width, and depth of 29.6≥5.5 mm, 21.0≥7.3 mm, and 14.3≥4.7 mm, respectively. Chronically, these lesions demonstrated uniform fibrotic changes without tissue disruption. Bipolar lesions were significantly deeper than the monopolar epicardial lesions. Conclusions: - This in vivo evaluation demonstrates that PFA can successfully ablate intracavitary structures, create deep epicardial lesions and transmural LV lesions.

2.
Chem Sci ; 15(19): 6994-7009, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38756809

RESUMEN

Ring-contracted porphyrin analogues, such as subporphyrins and calix[3]pyrroles, have recently attracted considerable attention not only as challenging synthetic targets but also as functional macrocyclic compounds. Although canonical porphyrins and calix[4]pyrrole are selectively generated via acid-catalyzed condensation reactions of pyrrole monomers, their tripyrrolic analogues are always missing under similar conditions. Recent progress in synthesis has shown that strain-controlled approaches using boron(iii)-templating, core-modification, or ring tightening provide access to various contracted porphyrins. The tripyrrolic macrocycles are a new class of functional macrocycles exhibiting unique ring-contraction effects, including strong boron chelation and strain-induced ring expansion. This Perspective reviews recent advances in synthetic strategies and the novel ring-contraction effects of subporphyrins, triphyrins(2.1.1), calix[3]pyrroles, and their analogous.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38758741

RESUMEN

Background:Unlike "conventional" microsecond pulsed electrical fields that primarily target the cell membranes, nanosecond pulses are thought to primarily electroporate intracellular organelles. We conducted a comprehensive preclinical assessment of catheter-based endocardial nanosecond pulsed field ablation (nsPFA) in swine. Methods: A novel endocardial nsPFA system was evaluated in a total of 25 swine. Using either a low-dose (5-second duration) or high-dose (15-second duration) strategy, thoracic veins and discrete atrial and ventricular sites were ablated. Swine were survived for <1 (n=1), ~2 (n=7), ~7 (n=6), 14 (n=2), or ~28 (n=9) days and venous isolation assessed before sacrifice. Safety assessments included evaluation of esophageal effects, phrenic nerve function, and changes in venous caliber. All tissues were subject to careful gross pathological and histopathological examination. Results: All (100%) veins (13 low-dose, 34 high-dose) were acutely isolated, and all reassessed veins (6 low-dose, 15 high-dose) were durably isolated. All examined vein lesions (10 low-dose, 22 high-dose) were transmural. Vein diameters (n=15) were not significantly changed. Of the animals assessed for phrenic palsy (n=9), 3 (33%) demonstrated only transient palsy. There were no differences between dosing strategies. Thirteen mitral isthmus lesions were analyzed and all 13 (100%) were transmural (depth 6.4±0.4mm). Ventricular lesions were 14.7±4.5mm wide and 7.1±1.3mm deep, with high-dose lesions deeper than low-dose (7.9±1.2mm vs 6.2±0.8mm, p=0.007). The esophagus revealed non-transmural adventitial surface lesions in 5 of 5 (100%) animals sacrificed early (2 days) post-ablation. In the 10 animals sacrificed later (14-28 days), all animals demonstrated significant esophageal healing - 8 with complete resolution, and 2 with only trace fibrosis. Conclusions: A novel, endocardial nanosecond PFA system provides acute and durable venous isolation and linear lesions. Transient phrenic injury and non-transmural esophageal lesions can occur with worst case assessments suggesting limits to PFA tissue selectivity and the need for dedicated assessments during clinical studies.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38544810

RESUMEN

Pulsed field ablation (PFA) is a novel energy form for the catheter ablation of cardiac arrhythmias, which uses electrical fields to mediate myocardial death via irreversible electroporation and other modalities. It is believed to offer relative tissue specificity, lowering - or even eliminating - the risk of complications associated with thermal energy, such as atrio-oesophageal fistulas. The proposed superior safety profile compared to thermal ablation has contributed to the enthusiastic implementation of PFA into clinical practice and is supported by early preclinical and clinical data. However, data about the effects of PFA on the oesophagus remain limited. This organ's susceptibility to PFA has important clinical ramifications and there are two highly relevant questions. First, is the oesophagus absolutely spared by PFA or is there susceptibility to injury at higher field strengths? Second, if oesophageal injury can occur, can atrio-oesophageal fistulas ensue? The aim of this article is to provide a literature review on the effects of PFA on the oesophagus and to address these questions based on the data described.

6.
J Affect Disord ; 354: 719-724, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38521134

RESUMEN

BACKGROUND: We investigated volumetric alterations in the bilateral choroid plexus (ChP) and brain ventricles of patients during their first episode of major depressive disorder (MDD) prior to antidepressant treatment. METHODS: Seventy-one first-episode drug-naïve patients with MDD and seventy-four healthy control (HC) subjects were recruited. MRI data were obtained, and bilateral ChP and brain ventricle volumes were evaluated using segmentation, based on the adaptive multiscale and expectation maximization method. One-way multivariate analysis of covariance was used to calculate volumetric differences in the bilateral ChP and brain ventricles between the groups, and partial Pearson correlation analyses were used to investigate the relationship between the volumes of the bilateral ChP and brain ventricles. RESULTS: First-episode drug-naïve patients with MDD showed enlarged volumes of the bilateral ChP, bilateral lateral ventricle (LV), and third ventricle compared with HCs. The ChP volume positively correlated with the LV and third ventricle, but not with the fourth ventricle in patients with MDD, whereas it correlated with all four brain ventricles in HCs. We did not observe significant correlations between bilateral ChP volume and brain ventricles, HAMD scores, or symptom severity. LIMITATIONS: Our study populations differed in age and sex and we did not extensively measure the amount of neuroinflammation in the brain or blood, include a functional assessment, nor evaluate other neural comorbidities or neuropsychiatric conditions. CONCLUSIONS: Our study extends the existing research to suggest that illness-related alterations in ChP volume enlargement in first-episode antidepressant-naïve patients with MDD may serve as a trait measure.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/tratamiento farmacológico , Plexo Coroideo/diagnóstico por imagen , Encéfalo , Mapeo Encefálico , Antidepresivos/uso terapéutico , Imagen por Resonancia Magnética
8.
Front Psychiatry ; 15: 1336370, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38510800

RESUMEN

Introduction: Major depressive disorder (MDD) is a major cause of poor quality of life and disability and is highly prevalent worldwide. Various pathological mechanisms are implicated in MDD, including the reward system. The human brain is equipped with a reward system that is involved in aspects such as motivation, pleasure, and learning. Several studies including a meta-analysis have been reported on the reward system network and MDD. However, to our knowledge, no studies have examined the relationship between the reward system network of drug-naïve, first-episode MDD patients and the detailed symptoms of MDD or age. The fronto-striato network (FSN) is closely related to the reward system network. The present study primarily aimed to elucidate this point. Methods: A total of 89 drug-naïve first-episode MDD patients and 82 healthy controls (HCs) patients were enrolled in the study. The correlation between the FSN and age and the interaction between age and illness in the FSN were investigated in 75 patients in the MDD group and 79 patients in the HC group with available information on the FSN and age. In addition, the association between the FSN and the total scores on the 17-item Hamilton Rating Scale for Depression (HAMD-17) and scores in each symptom item was analyzed in 76 MDD subjects with information on the FSN and HAMD-17. The significance of each result was evaluated according to a p-value of <0.05. Results: Age was inversely correlated with the FSN (p=2.14e-11) in the HC group but not in the MDD group (p=0.79). FSN varied with the presence of MDD and with age, particularly showing an interaction with MDD and age (p=1.04e-08). Specifically, age and the presence or absence of MDD each affected FSN, but the effect of age on FSN changed in the presence of depression. FSN did not correlate with total HAMD-17 scores or scores in each item. Discussion: The reward system may be dysfunctional in patients with MDD. In addition, the effect could be greater in younger patients. Meanwhile, there is no correlation between the function of the reward system and the severity of MDD or the severity of each symptom. Thus, the reward system network may be an important biological marker of MDD, although careful consideration should be given to age and its association with the severity of the disorder. Conclusion: The reward system function is decreased in MDD patients, and this decrease may be more pronounced in younger patients, although further research is still needed.

9.
Appl Opt ; 63(7): B126-B133, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38437263

RESUMEN

A computer-generated hologram (CGH) enables the display of virtual images and videos as well as the communication and storage of holographic data. The point-based method, which is a CGH-calculation method for representing the surface of an object as a set of point-light sources, has not been sufficiently studied in terms of realistic representation. This paper proposes a CGH-calculation method for realistic rendering using ray tracing to be used with a point-based method. Experiments were conducted with an optical system to confirm the effectiveness of the proposed method in terms of hidden-surface removal in mirror images and its implementation on multiple mirror surfaces. The results indicate that the proposed method enabled hidden-surface removal with continuous parallax and reflection on mirror surfaces.

10.
Clin Nutr ; 43(3): 773-780, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38335802

RESUMEN

BACKGROUND AND AIMS: Studies reported that knee extension strength on the operated side in patients with hip fractures was not recovered to the level on the non-operated side 6 months after surgery or later. In a cross-sectional study, we revealed that a reduction in isometric knee extension muscle strength on the operated side in patients with hip fractures approximately 6 months after surgery was associated with not only a reduction in skeletal muscle mass but also a reduction in muscle quality, characterized by a reduction in the phase angle (PhA). Furthermore, the mechanisms of knee extension strength improvement can be clarified in more detail using the minimal significant change as the index of recovery. However, no longitudinal studies have examined the factors for knee extension strength improvement based on the minimal significant change in patients with hip fractures 6 months after surgery. This study aimed to longitudinally examine the factors influencing the recovery of knee extension strength based on the minimal significant change in patients with hip fractures between 2 weeks and approximately 6 months after surgery. METHODS: In this study, the outcomes used were basic and medical information, PhA, skeletal muscle index (SMI), pain, one-leg standing time, movement control during one-leg standing, and walking speed. For PhA, SMI, pain, one-leg standing time, movement control during one-leg standing, and walking speed, the amount of change was calculated by subtracting the data at 2 weeks from the data at 6 months. Group classification was determined by dividing the patients into two groups using a previous study as a reference: recovery group if the knee extension strength value approximately 6 months after surgery minus that 2 weeks after surgery was ≥3.3 kgf and non-recovery group if the value was <3.3 kgf. Logistic regression analysis was performed to explore the association between the recovery and non-recovery groups. RESULTS: The recovery group contained 55 patients, while the non-recovery group comprised 35 patients. The only significant factor associated with knee extension muscle strength in the recovery group was the amount of change in PhA. The odds ratio for the amount of change in PhA was 2.26. The discrimination rate of the model was 62.5%. CONCLUSIONS: Our results suggest that recovery of knee extension strength in patients with hip fractures after surgery was mainly because of improvements in muscle quality, not improvements in muscle mass or pain.


Asunto(s)
Fracturas de Cadera , Articulación de la Rodilla , Humanos , Estudios Transversales , Articulación de la Rodilla/cirugía , Músculo Esquelético , Fracturas de Cadera/cirugía , Dolor
12.
Acad Radiol ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38413313

RESUMEN

RATIONALE AND OBJECTIVES: Although hyperintensity in the anterior portion of the callosal splenium on FLAIR (aCS-hyperintensity) is a common finding in elderly adults, no previous studies have examined the clinical significance. In this large elderly population study, we aimed to investigate the associations of aCS-hyperintensity with vascular risk factors, cognitive decline, and other MRI measurements. MATERIALS AND METHODS: This cross-sectional study included 2110 participants (median age, 69 years; 61.1% females) who underwent 3 T MRI. The participants were grouped as 215 with mild cognitive impairment (MCI) and 1895 cognitively normal older adults (NOAs). Two neuroradiologists evaluated aCS-hyperintensity by using a four-point scale (none, mild, moderate, and severe). Periventricular hyperintensities (PVHs) were also rated on a four-point scale according to the Fazekas scale. The total intracranial volume (ICV), total brain volume, choroid plexus volume (CPV), and lateral ventricle volume (LVV) were calculated. RESULTS: Logistic regression analysis showed diabetes was the main predictor of aCS-hyperintensity after adjusting for potential confounders (age, sex, hypertension, and hyperlipidemia) (p < 0.01), whereas PVH was associated with hypertension (p < 0.01). aCS-hyperintensity rated as "severe" was associated with a presence of MCI (p < 0.01). For the imaging factors, LVV was an independent predictor of aCS-hyperintensity when brain volume and PVH grade were added to the analysis (p < 0.01). CONCLUSION: Cerebral small vessel disease due to diabetes is a major contributor to the development of aCS-hyperintensity. Cerebrospinal fluid clearance failure may also relate to aCS-hyperintensity, which may offer new insights into the pathologic processes underlying MCI.

13.
Neuroradiology ; 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38374411

RESUMEN

PURPOSE: To evaluate the diagnostic value of T1-weighted 3D fast spin-echo sequence (CUBE) with deep learning-based reconstruction (DLR) for depiction of pituitary adenoma and parasellar regions on contrast-enhanced MRI. METHODS: We evaluated 24 patients with pituitary adenoma or residual tumor using CUBE with and without DLR, 1-mm slice thickness 2D T1WI (1-mm 2D T1WI) with DLR, and 3D spoiled gradient echo sequence (SPGR) as contrast-enhanced MRI. Depiction scores of pituitary adenoma and parasellar regions were assigned by two neuroradiologists, and contrast-to-noise ratio (CNR) was calculated. RESULTS: CUBE with DLR showed significantly higher scores for depicting pituitary adenoma or residual tumor compared to CUBE without DLR, 1-mm 2D T1WI with DLR, and SPGR (p < 0.01). The depiction score for delineation of the boundary between adenoma and the cavernous sinus was higher for CUBE with DLR than for 1-mm 2D T1WI with DLR (p = 0.01), but the difference was not significant when compared to SPGR (p = 0.20). CUBE with DLR had better interobserver agreement for evaluating adenomas than 1-mm 2D T1WI with DLR (Kappa values, 0.75 vs. 0.41). The CNR of the adenoma to the brain parenchyma increased to a ratio of 3.6 (obtained by dividing 13.7, CNR of CUBE with DLR, by 3.8, that without DLR, p < 0.01). CUBE with DLR had a significantly higher CNR than SPGR, but not 1-mm 2D T1WI with DLR. CONCLUSION: On the contrast-enhanced MRI, compared to CUBE without DLR, 1-mm 2D T1WI with DLR and SPGR, CUBE with DLR improves the depiction of pituitary adenoma and parasellar regions.

14.
Eur Radiol ; 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38221583

RESUMEN

OBJECTIVES: Previous studies have shown possible choroid plexus (CP) dysfunction in Alzheimer's disease (AD) and highlighted CP enlargement on magnetic resonance imaging (MRI) as a predictive factor of AD. However, few studies have assessed the relationship between CP volume (CPV) and mild cognitive impairment (MCI). In this large elderly population study, we investigated the changes in CPV in patients with MCI using MRI above 65 years. METHODS: This cross-sectional study included 2144 participants (median age, 69 years; 60.9% females) who underwent 3T MRI; they were grouped as 218 MCI participants and 1904 cognitively healthy controls. The total intracranial volume (ICV), total brain volume (TBV), CPV, hippocampal volume (HV), and lateral ventricle volume (LVV) were calculated. RESULTS: CPV/ICV was a significant independent predictor of MCI (p < 0.01) after adjusting for potential confounders (age, sex, hypertension, hyperlipidemia, diabetes, and education level). The CPV/ICV ratio was also a significant independent predictor of MCI after adjusting for the TBV/ICV ratio (p = 0.022) or HV/ICV ratio (p = 0.017), in addition to potential confounders. The CPV was significantly correlated with the LVV (r = 0.97, p < 0.01). CONCLUSION: We identified a relationship between CPV and MCI, which could not be explained by the degree of brain atrophy. Our results support CP dysfunction in MCI. CLINICAL RELEVANCE STATEMENT: Choroid plexus volume measurement may serve as a valuable imaging biomarker for diagnosing and monitoring mild cognitive impairment. The enlargement of the choroid plexus, independent of brain atrophy, suggests its potential role in mild cognitive impairment pathology. KEY POINTS: • The study examines choroid plexus volume in relation to cognitive decline in elderly. • Enlarged choroid plexus volume independently indicates mild cognitive impairment presence. • Choroid plexus volume could be a specific biomarker for early mild cognitive impairment diagnosis.

15.
Heart Rhythm ; 21(4): 389-396, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38159790

RESUMEN

BACKGROUND: Ultrastructural findings immediately after pulsed field ablation (PFA) of the myocardium have not been described. OBJECTIVES: The purpose of this study was to elucidate ultrastructural characteristics and differences between microsecond PFA at the 1- and 4-hour timepoints after pulse delivery and to compare them to irrigated radiofrequency ablation (RFA) lesions. METHODS: Healthy swine underwent endocardial PFA or RFA followed by necropsy. Discrete microsecond PFA and irrigated RFA lesions were created in the ventricles with a lattice tip ablation catheter. Lesions were delivered in a manner so as to allow sampling to occur 1 and 4 hours after ablation. All lesions were located at necropsy, and samples were carefully obtained from within the lesion core, lesion periphery, and adjacent healthy myocardium. Transmission electron microscopic assessment was performed after fixation using paraformaldehyde and glutaraldehyde. RESULTS: One hour after microsecond PFA delivery, myocytes were noted to be significantly and uniformly disrupted. Clustered, misaligned, swollen mitochondria coupled with degenerating nuclei and condensed chromatin were visualized. These findings progressed over the subsequent few hours with worsening edema. Similar changes were seen with RFA but reduced in severity. However, there was prominent extravasation of red blood cells with occlusion of capillaries that was not seen in PFA. At the lesion periphery, an abrupt change in the degree of myocyte damage was observed with PFA but not RFA. CONCLUSION: Transmission electron microscopy demonstrates evidence of widespread destruction of myocytes as early as an hour after PFA and corroborates known histologic features such as sparing of vessels and sharp lesion margins.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Ablación por Radiofrecuencia , Porcinos , Animales , Ablación por Catéter/efectos adversos , Miocardio , Ventrículos Cardíacos/cirugía , Frecuencia Cardíaca , Fibrilación Atrial/cirugía
16.
J Affect Disord ; 340: 923-929, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37598718

RESUMEN

OBJECTIVE: To investigate the effect of electroconvulsive treatment (ECT) on dynamic structural network connectivity in major depressive disorder (MDD), based on the triple-network model. METHODS: Twenty-one first-episode, drug-naïve patients with MDD and 21 age- and sex-matched healthy subjects were recruited. Bilateral electrical stimulation was performed thrice a week for a total of 4-5 weeks in the MDD group. MRI data were obtained, and triple-network structural connectivity was evaluated using source-based morphometry (SBM) analysis. A paired t-test was used to analyze structural connectivity differences between pre- and post-ECT MDD groups, one-way analysis was used to calculate three intrinsic network differences between HCs, pre- and post-ECT groups, and partial least squares structural equation modelling was used to investigate dynamic structural network connectivity (dSNC) across groups. RESULTS: Pre-ECT patients with MDD exhibited significantly lower salience network (SN) structural connectivity (p = 0.010) than the healthy control (HC) group and after ECT therapy SN structural connectivity was significantly elevated (p = 0.002) in post-ECT group compared with pre-ECT. PLS-SEM analysis conducted on inter-network connectivity in the triple-network model indicated a significant difference between SN and central executive network (CEN) in all three groups. The HC and post-ECT MDD groups showed notable direct connectivity between the SN and default mode network (DMN), while the pre-ECT MDD group showed consequential pathological connectivity between the CEN and DMN. A mediation analysis revealed a significant indirect effect of the SN on the DMN through the CEN (ß = 0.363, p = 0.008) only in the pre-ECT MDD group. CONCLUSIONS: ECT may be an effective and minimally invasive treatment for addressing structural changes in the SN and direct communication abnormalities between the three core brain networks in patients with MDD, with possible beneficial correction of indirect connections.


Asunto(s)
Trastorno Depresivo Mayor , Terapia Electroconvulsiva , Humanos , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/terapia , Encéfalo , Grupos Control , Comunicación
17.
Sci Rep ; 13(1): 13330, 2023 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-37587138

RESUMEN

Although altered networks inside the hippocampus (hippocampal intra-networks) have been observed in dementia, the evaluation of hippocampal intra-networks using magnetic resonance imaging (MRI) is challenging. We employed conventional structural imaging and incident component analysis (ICA) to investigate the structural covariance of the hippocampal intra-networks. We aimed to assess altered hippocampal intra-networks in patients with mild cognitive impairment (MCI). A cross-sectional study of 2122 participants with 3T MRI (median age 69 years, 60.9% female) were divided into 218 patients with MCI and 1904 cognitively normal older adults (CNOA). By employing 3D T1-weighted imaging, voxels within the hippocampus were entered into the ICA analysis to extract the structural covariance intra-networks within the hippocampus. The ICA extracted 16 intra-networks from the hippocampal structural images, which were divided into two bilateral networks and 14 ipsilateral networks. Of the 16 intra-networks, two (one bilateral network and one ipsilateral networks) were significant predictors of MCI from the CNOA after adjusting for age, sex, education, disease history, and hippocampal volume/total intracranial volume ratio. In conclusion, we found that the relationship between hippocampal intra-networks and MCI was independent from the hippocampal volume. Our results suggest that altered hippocampal intra-networks may reflect a different pathology in MCI from that of brain atrophy.


Asunto(s)
Disfunción Cognitiva , Pueblos del Este de Asia , Anciano , Humanos , Femenino , Masculino , Estudios Transversales , Disfunción Cognitiva/diagnóstico por imagen , Escolaridad , Hipocampo/diagnóstico por imagen
18.
Sci Rep ; 13(1): 11519, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37460617

RESUMEN

Organs-on-chips using cultured cells have been developed and applied for evaluating in vitro biological phenomena. We previously reported an openable artificial intestinal tract system, as an in vitro model of the small intestine, for in vitro drug screening. The intestinal tract device could be transformed using an integrated artificial muscle actuator. An initial flat state was suitable for cell culture, and the transformed tubular structure was used as a fluidic channel for perfusion tests. The previously developed intestinal tract system could be used to evaluate drug absorption by cells through perfusion testing. This study presents an improved artificial intestinal tract system for analysis of drug permeation, in addition to absorption. Permeable filters were integrated into the intestinal tract device. Integration of additional filters into the design of the existing artificial muscle actuator was accomplished by considering device performance and available filter locations. Filter permeability was evaluated by perfusion testing. MDCK-II cells were cultured on the device and visually and electrically evaluated. The openable device, equipped with new functions for further pharmacokinetic analysis, could perform and evaluate drug disposition using cultured cells. We anticipate that the improved, openable organ-on-a-chip device system will contribute to advances in in vitro drug screening technology.


Asunto(s)
Tracto Gastrointestinal , Intestinos , Animales , Perros , Técnicas de Cultivo de Célula , Células de Riñón Canino Madin Darby , Administración Oral , Permeabilidad , Absorción Intestinal/fisiología
19.
Biochem Biophys Res Commun ; 664: 94-99, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37141642

RESUMEN

In nonclinical studies, models that can predict the metabolism of drug candidates by cytochrome P450 (CYP), including Cytochrome P450 family 3 subfamily A member 4 (CYP3A4) are helpful. CYP3A4-overexpressing human cells have been used universally to evaluate whether CYP3A4 metabolizes drug-candidate compounds. However, CYP3A4-overexpressing human cell lines are problematic because their activity levels are lower than that of in vivo human CYP3A4. Heme plays a paramount role in CYP activity. The rate-limiting step in heme biosynthesis is the generation of 5-aminolevulinic acid (5-ALA). In this study, we examined whether treatment with 5-ALA to CYP3A4-POR-UGT1A1-CES2 knockin and CES1 knockout (genome-edited) Caco-2 cells enhances CYP3A4 activity. A 7-day 5-ALA treatment increased intracellular heme levels in genome-edited Caco-2 cells without cytotoxicity. Moreover, consistent with the increase in intracellular heme content, 5-ALA treatment increased CYP3A4 activity in genome-edited Caco-2 cells. The results of this research are expected to be applied to pharmacokinetic studies using CYP-overexpressing human cells containing CYP3A4.


Asunto(s)
Ácido Aminolevulínico , Citocromo P-450 CYP3A , Humanos , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Células CACO-2 , Ácido Aminolevulínico/farmacología , Hemo , Sistema Enzimático del Citocromo P-450/metabolismo
20.
Pacing Clin Electrophysiol ; 46(6): 475-486, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37129189

RESUMEN

BACKGROUNDS: Catheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM). METHODS: The study was a single-center, retrospective observational study. We enrolled 171 consecutive patients who underwent de-novo catheter ablation for non-PAF under conscious sedation with a novel extensive ablation strategy that included CBA for pulmonary vein isolation (PVI) and left atrial roof ablation (LARA), RFA for mitral isthmus (MI) ablation, superior vena cava isolation, and other linear ablations and EA-VOM. Recurrence of atrial arrhythmias over 1 year, procedure outcomes, and procedure-related complications were investigated. RESULTS: A total of 139 (81.3%) patients remained in sinus rhythm during 1-year follow-up. Of the 139 patients, 51 patients (29.8%) received antiarrhythmic drugs. The mean procedure time was 204 ± 45 min. PVI and LARA ablation by CBA and MI block by RFA and EA-VOM were completed in 171 (100%) and 166 (97.1%) patients, respectively. No serious procedure-related complications were observed except for one case of delayed pericardial effusion. CONCLUSION: Approximately 80% of the study patients were AF-free during 1-year follow-up period after a single procedure based on the novel extensive ablation strategy combining CBA, RFA, and EA-VOM. This strategy for non-PAF may be preferred in terms of maintenance of sinus rhythm, safety even in high-risk patients, and relatively short procedure time.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Venas Pulmonares , Humanos , Etanol , Vena Cava Superior , Atrios Cardíacos , Venas Pulmonares/cirugía , Criocirugía/métodos , Ablación por Catéter/métodos , Resultado del Tratamiento , Recurrencia
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