USP28 promotes tumorigenesis and cisplatin resistance by deubiquitinating MAST1 protein in cancer cells.

Cisplatin is a chemotherapy drug that causes a plethora of DNA lesions and inhibits DNA transcription and replication, resulting in the induction of apoptosis in cancer cells. However, over time, patients develop resistance to cisplatin due to repeated treatment and thus the treatment efficacy is limited. Therefore, identifying an alternative therapeutic strategy combining cisplatin treatment along with targeting factors that drive cisplatin resistance is needed. CRISPR/Cas9 system-based genome-wide screening for the deubiquitinating enzyme (DUB) subfamily identified USP28 as a potential DUB that governs cisplatin resistance. USP28 regulates the protein level of microtubule-associated serine/threonine kinase 1 (MAST1), a common kinase whose expression is elevated in several cisplatin-resistant cancer cells. The expression level and protein turnover of MAST1 is a major factor driving cisplatin resistance in many cancer types. Here we report that the USP28 interacts and extends the half-life of MAST1 protein by its deubiquitinating activity. The expression pattern of USP28 and MAST1 showed a positive correlation across a panel of tested cancer cell lines and human clinical tissues. Additionally, CRISPR/Cas9-mediated gene knockout of USP28 in A549 and NCI-H1299 cells blocked MAST1-driven cisplatin resistance, resulting in suppressed cell proliferation, colony formation ability, migration and invasion in vitro. Finally, loss of USP28 destabilized MAST1 protein and attenuated tumor growth by sensitizing cells to cisplatin treatment in mouse xenograft model. We envision that targeting the USP28-MAST1 axis along with cisplatin treatment might be an alternative therapeutic strategy to overcome cisplatin resistance in cancer patients.

Predictive Scoring System for Spontaneous Closure of Infant Ventricular Septal Defect: The P-VSD Score.

Ventricular septal defect (VSD) is a common congenital heart disease. However, consensus on the utility of echocardiography in predicting spontaneous closure (SC) of VSD remains lacking. This study aimed to identify and validate significant predictors of SC through a predictive scoring system. This retrospective study included medical records of 712 echocardiography instances performed on 304 patients diagnosed with VSD from 2016 to 2020 in their first year of life. A novel scoring system for predicting the SC of VSD was developed and validated using another dataset from different hospitals. Of the 304 patients, 215 (70.7%) had perimembranous (PM) VSDs and 89 had muscular (29.3%) VSDs. The median follow-up periods were 36.2 (interquartile range [IQR], 13-59) months and 13.7 9 (IQR, 5-37.4) days for PM and muscular VSDs, respectively. The overall SC rate during follow-up was 29.3%. Pulmonary hypertension (HTN), concomitant left ventricle (LV)-right atrium (RA) shunt, VSD size to aortic valve (AV) annulus size ratio, and left ventricular end-diastolic dimension (LVEDD) z-score were significant risk factors affecting SC of VSD. The "P-VSD" score, a new scoring system, demonstrated an area under the curve for predictability of 0.769. Pulmonary HTN, concomitant LV-RA shunt, LVEDD z-score, and VSD size-to-AV annulus size ratio at diagnosis were significantly associated with non-SC VSD after infancy. The P-VSD score can predict the SC of VSD in clinical settings and simplify the identification and appropriate management of high-risk patients.

Effects of Familial Relationships on School Adjustment of Adolescents and Young Adults With Congenital Heart Disease.

BACKGROUND: As more than 85% of patients with congenital heart disease (CHD) have grown to adulthood through improvement in treatment and surgery, the difficulties they experience are expanding into areas related to daily life. Accordingly, adjustment to school in adolescents and young adults (AYAs) with CHD is of increasing interest and is influenced by familial factors. OBJECTIVE: This was a cross-sectional descriptive study to examine the effects of parental positive emotional expressiveness and sibling relationships on school adjustment of AYAs with CHD. METHODS: In this study, a self-reported questionnaire survey was used to collect the data. The participants were 104 AYAs with CHD aged 13 to 21 years who were attending school and had siblings. RESULTS: Maternal positive emotional expressiveness ( r = 0.584, P < .01), paternal positive emotional expressiveness ( r = 0.584, P < .01), and sibling warmth/closeness ( r = 0.478, P < .01) were significantly correlated with school adjustment. However, the results of multiple regression analysis showed that only maternal positive emotional expressiveness (ß = 0.459, P < .05) and sibling warmth/closeness (ß = 0.236, P < .05) were significantly associated with school adjustment. CONCLUSIONS: Adolescents and young adults with CHD who reported higher maternal positive emotional expressiveness and sibling warmth/closeness exhibited better school adjustment. Findings suggest that intervention programs to increase parental positive expressiveness and enhance warmth/closeness of sibling relationships may contribute to improving school adjustment.

VERD: Emergence of Product-Based Video E-Commerce Retrieval Dataset from User's Perspective.

Customer demands for product search are growing as a result of the recent growth of the e-commerce market. According to this trend, studies on object-centric retrieval using product images have emerged, but it is difficult to respond to complex user-environment scenarios and a search requires a vast amount of data. In this paper, we propose the Video E-commerce Retrieval Dataset (VERD), which utilizes user-perspective videos. In addition, a benchmark and additional experiments are presented to demonstrate the need for independent research on product-centered video-based retrieval. VERD is publicly accessible for academic research and can be downloaded by contacting the author by email.

Associations between Prolactin, Diabetes, and Cognitive Impairment: A Literature Review.

BACKGROUND: Converging evidence indicates prolactin (PRL) and diabetes play an important role in the pathophysiology of cognitive impairment. However, little is known about the mechanisms responsible for the effects of PRL and diabetes on cognitive impairment. SUMMARY: We summarize and review the available literature and current knowledge of the association between PRL and diabetes on aspects of cognitive impairment. KEY MESSAGES: The phosphatidylinositol 3-kinase/protein kinase B pathway is central to the molecular mechanisms underlying how PRL and diabetes interact in cognitive impairment. Further work is needed to identify the interaction between PRL and diabetes, especially in the molecular aspects of cognitive impairment, which can suggest novel strategies for cognitive dysfunction treatment.

Prolactin and Its Altered Action in Alzheimer's Disease and Parkinson's Disease.

BACKGROUND: Prolactin (PRL) is one of the most diverse pituitary hormones and is known to modulate normal neuronal function and neurodegenerative conditions. Many studies have described the influence that PRL has on the central nervous system and addressed its contribution to neurodegeneration, but little is known about the mechanisms responsible for the effects of PRL on neurodegenerative disorders, especially on Alzheimer's disease (AD) and Parkinson's disease (PD). SUMMARY: We review and summarize the existing literature and current understanding of the roles of PRL on various PRL aspects of AD and PD. KEY MESSAGES: In general, PRL is viewed as a promising molecule for the treatment of AD and PD. Modulation of PRL functions and targeting of immune mechanisms are needed to devise preventive or therapeutic strategies.

Associations among the TREM-1 Pathway, Tau Hyperphosphorylation, Prolactin Expression, and Metformin in Diabetes Mice.

INTRODUCTION: Diabetes mellitus (DM) is a risk factor for Alzheimer's disease (AD). Increasing evidence indicates that the triggering receptor expressed on myeloid cells (TREM)-1 amplifies chronic inflammation, as well as the roles of prolactin (PRL) and metformin (MET) in tau hyperphosphorylation. However, the associations among TREM-1, tau hyperphosphorylation, PRL expression, and MET in DM remain unclear. METHODS: Streptozotocin was used to induce experimental DM in C57BL/6N mice. MET was orally administered at a dose of 400 mg/kg body weight for 6 weeks prior to hippocampal collection in DM mice. Various parameters pertaining to the TREM-1 pathway, tau hyperphosphorylation, PRL, and related factors were analyzed. RESULTS: Quantitative polymerase chain reaction and Western blot analysis demonstrated that the expression levels of TREM-1, DAP12, casp1, interleukin-1ß, Cox2, inducible nitric oxide synthase, pituitary transcriptional factor-1 (Pit-1), and PRL were significantly increased in the hippocampus of DM mice; the expression levels of these pro-inflammatory mediators, PRL receptor (PRLR) short or long (PRLR-S and PRLR-L), and PRL regulatory element-binding (Preb) protein in DM mice treated with MET (DM + MET) were significantly decreased compared with those in control (CON) mice. The levels of p-Tau and glycogen synthase kinase-3 in the DM group were significantly higher than those in the CON group and significantly lower than those in the DM + MET group. CONCLUSION: We confirmed the therapeutic potential of MET for both DM and neurodegeneration. Our findings shed new light on the effects of DM on the pathophysiology of AD via the TREM-1 pathway and PRL expression. Thus, an improved understanding of the TREM-1 pathway in hyperglycemic conditions, as well as PRL, Preb, Pit-1, PRLR-L, and PRLR-S gene expression in the liver, brain, and other sites, may help unravel the pathogenesis of insulin resistance and neurodegeneration.

Association between Serum Prolactin Levels and Neurodegenerative Diseases: Systematic Review and Meta-Analysis.

INTRODUCTION: Prolactin (PRL) exerts inflammatory and anti-inflammatory properties and is also thought to play an important role in the pathogenesis of neurodegenerative diseases (NDs). However, serum PRL levels in patients with NDs were inconsistent in the research literature. OBJECTIVE: We aimed to assess the serum PRL levels in patients with NDs. METHODS: Electronic databases, including MEDLINE, Embase, Cochrane Library database, clinicaltrials.gov, Web of Science, and Google Scholar, and reference lists of articles were searched up to December 31, 2020. Pooled standard mean difference (SMD) with 95% confidence interval (CI) was calculated by fixed-effect or random-effect model analysis. RESULTS: A total of 36 comparisons out of 29 studies (3 RCTs and 26 case controls) focusing on NDs (including Parkinson's disease, Alzheimer's disease, Huntington's disease [HD], multiple sclerosis [MS], and epilepsy) were reported. The meta-analysis showed that there was no statistically significant difference in serum PRL levels between patients with NDs and healthy controls (SMD = 0.40, 95% CI: -0.16 to 0.96, p = 0.16). Subgroup analysis showed that serum PRL levels in patients with HD and MS were higher than those of healthy controls. Furthermore, patients with NDs aged <45 years had higher serum PRL levels (SMD = 0.97, 95% CI: 0.16-1.78, p = 0.018) than healthy controls. High serum PRL levels were found in subgroups such as the microenzymatic method, Asia, and the Americas. CONCLUSIONS: Our meta-analysis showed serum PRL levels in patients with HD and MS were significantly higher than those in healthy controls. Serum PRL levels were associated with age, region, and detection method. Other larger sample studies using more uniform detection methods are necessary to confirm our results.

Performance evaluation of biodegradable polymer sirolimus and ascorbic acid eluting stent systems.

The purpose of this study was to evaluate the performance of biodegradable polymer sirolimus and ascorbic acid eluting stent systems with four commercially available drug-eluting stents (DES). We investigated the characterization of mechanical properties by dimension, foreshortening, recoil, radial force, crossing profile, folding shape, trackability, and dislodgement force. Additionally, we identify the safety and efficacy evaluation through registry experiments. Each foreshortening and recoil of D + Storm® DES is 1.3 and 3.70%, which has better performance than other products. A post-marketing clinical study to evaluate the performance and safety of D + Storm® DES is ongoing in real-world clinical settings. Two hundred one patients were enrolled in this study and have now completed follow-up for up to 1 month. No major adverse cardiovascular event (MACE) occurred in any subjects, confirming the safety of D + Storm® DES in the clinical setting. An additional approximately 100 subjects will be enrolled in the study and the final safety profile will be assessed in 300 patients. In conclusion, this study reported the objective evaluation of DES performance and compared the mechanical responses of four types of DES available in the market. There is little difference between the four cardiovascular stents in terms of mechanical features, and it can help choose the most suitable stent in a specific clinical situation if those features are understood. Graphical abstract.

Can concomitant above-knee femoropopliteal bypass with artificial graft affect the outcome of femorofemoral bypass with artificial graft?

OBJECTIVES: Few have studied the effect of concomitant femoropopliteal (FEM-POP) bypass surgery on the outcome of femorofemoral (FEM-FEM) bypass in patients with peripheral arterial disease (PAD). This study was aimed to analyze the risk relationship of concomitant FEM-POP bypass on the patency of FEM-FEM bypass. METHODS: From March 2009 to April 2020, a total of 27 patients who underwent FEM-FEM bypass surgery using polytetrafluoroethylene grafts were retrospectively analyzed according to concomitant FEM-POP bypass surgery. The mean follow-up duration was 38.20 ± 34.56 months. RESULTS: The overall primary patency of the FEM-FEM bypass grafts in all 27 patients was 83.7, 78.5, and 72.0 at one, two, and 3 years, respectively. The overall limb salvage rate was 100, 94.1, and 86.9 at one, two, 3 years, respectively. Among them, ten patients underwent FEM-FEM bypass only (group 1). The other 17 patients needed a concomitant FEM-POP bypass and these patients were classified into three groups (group 2, ipsilateral FEM-POP, n = 5; group 3, crossover FEM-POP, n = 6; and group 4, bilateral FEM-POP, n = 6) The comparison of the primary patency of group 1 with the concomitant FEM-POP groups (sum of groups 2, 3, and 4, that is, group 5, n = 17) revealed a statistically significant improved patency for FEM-FEM bypasses not requiring concomitant infra-inguinal bypass (p = .036). Among the concomitant FEM-POP groups, group 2 had the lowest primary patency of the FEM-FEM bypass significantly (p = 0.07). The limb salvage rate of group 4 was significantly low. CONCLUSIONS: A concomitant FEM-POP bypass influenced the outcome of FEM-FEM bypass surgery. In conclusion, compromised infra-inguinal runoff at either extremity requiring concomitant FEM-POP bypass significantly worsens long-term FEM-FEM bypass patency. In addition, a concomitant bilateral FEM-POP bypass is a risk factor affecting the limb salvage rate in FEM-FEM bypass.

Multispectral Benchmark Dataset and Baseline for Forklift Collision Avoidance.

In this paper, multispectral pedestrian detection is mainly discussed, which can contribute to assigning human-aware properties to automated forklifts to prevent accidents, such as collisions, at an early stage. Since there was no multispectral pedestrian detection dataset in an intralogistics domain, we collected a dataset; the dataset employs a method that aligns image pairs with different domains, i.e. RGB and thermal, without the use of a cumbersome device such as a beam splitter, but rather by exploiting the disparity between RGB sensors and camera geometry. In addition, we propose a multispectral pedestrian detector called SSD 2.5D that can not only detect pedestrians but also estimate the distance between an automated forklift and workers. In extensive experiments, the performance of detection and centroid localization is validated with respect to evaluation metrics used in the driving car domain but with distinct categories, such as hazardous zone and warning zone, to make it more applicable to the intralogistics domain.

Ubiquitin-Specific Protease 3 Deubiquitinates and Stabilizes Oct4 Protein in Human Embryonic Stem Cells.

Oct4 is an important mammalian POU family transcription factor expressed by early human embryonic stem cells (hESCs). The precise level of Oct4 governs the pluripotency and fate determination of hESCs. Several post-translational modifications (PTMs) of Oct4 including phosphorylation, ubiquitination, and SUMOylation have been reported to regulate its critical functions in hESCs. Ubiquitination and deubiquitination of Oct4 should be well balanced to maintain the pluripotency of hESCs. The protein turnover of Oct4 is regulated by several E3 ligases through ubiquitin-mediated degradation. However, reversal of ubiquitination by deubiquitinating enzymes (DUBs) has not been reported for Oct4. In this study, we generated a ubiquitin-specific protease 3 (USP3) gene knockout using the CRISPR/Cas9 system and demonstrated that USP3 acts as a protein stabilizer of Oct4 by deubiquitinating Oct4. USP3 interacts with endogenous Oct4 and co-localizes in the nucleus of hESCs. The depletion of USP3 leads to a decrease in Oct4 protein level and loss of pluripotent morphology in hESCs. Thus, our results show that USP3 plays an important role in controlling optimum protein level of Oct4 to retain pluripotency of hESCs.

Bioactive Lipid O-cyclic phytosphingosine-1-phosphate Promotes Differentiation of Human Embryonic Stem Cells into Cardiomyocytes via ALK3/BMPR Signaling.

Adult human cardiomyocytes have an extremely limited proliferative capacity, which poses a great barrier to regenerative medicine and research. Human embryonic stem cells (hESCs) have been proposed as an alternative source to generate large numbers of clinical grade cardiomyocytes (CMs) that can have potential therapeutic applications to treat cardiac diseases. Previous studies have shown that bioactive lipids are involved in diverse cellular responses including cardiogenesis. In this study, we explored the novel function of the chemically synthesized bioactive lipid O-cyclic phytosphingosine-1-phosphate (cP1P) as an inducer of cardiac differentiation. Here, we identified cP1P as a novel factor that significantly enhances the differentiation potential of hESCs into cardiomyocytes. Treatment with cP1P augments the beating colony number and contracting area of CMs. Furthermore, we elucidated the molecular mechanism of cP1P regulating SMAD1/5/8 signaling via the ALK3/BMP receptor cascade during cardiac differentiation. Our result provides a new insight for cP1P usage to improve the quality of CM differentiation for regenerative therapies.

A stepwise approach to conduit puncture for electrophysiological procedures in patients with Fontan circulation.

Aims: In patients with Fontan circulation, the conduit may be punctured for electrophysiological procedures. We evaluated the feasibility and safety of a stepwise approach to conduit puncture in adults who have undergone Fontan operation. Methods and results: We included 13 consecutive patients with lateral tunnel or extracardiac conduit Fontan circulation [median age (interquartile range), 24.0 (16.0-25.0) years; seven men] who had undergone electrophysiological procedures. We performed a stepwise approach to conduit puncture: 1st, Brockenbrough needle; 2nd, Brockenbrough needle with snare; 3rd, extra-steep Brockenbrough needle with/without snare; 4th radiofrequency transseptal needle with/without snare; 5th, wiring through the puncture; 6th, conduit dilation with angioplasty balloon; 7th, non-compliant or cutting balloon; and 8th, Inoue dilator. In 12 patients, conduit puncture was successful. In two, one, and two patients with a lateral tunnel made of the pericardium or right atrial wall, conduit puncture was performed by steps 1st, 2nd, and 4th, respectively. In one, three, two, and one patient with the Goretex lateral tunnel or extracardiac conduit, conduit puncture was performed by steps 1st, 6th, 7th, and 8th, respectively. Puncture time was significantly longer in patients with Goretex conduits than with pericardial conduits [62.0 (50.0-120.0) and 11.5 (10.0-14.8) min, respectively; P < 0.001]. A snare was necessary in patients with angles ≤ 35° between the conduit wall and vertical line. Conclusion: A stepwise conduit puncture approach is feasible and safe in patients with lateral tunnel and extracardiac conduit Fontan circulation. Goretex conduit puncture was more difficult than pericardial conduit puncture.

Phase transition-induced band edge engineering of BiVO4 to split pure water under visible light.

Through phase transition-induced band edge engineering by dual doping with In and Mo, a new greenish BiVO4 (Bi1-XInXV1-XMoXO4) is developed that has a larger band gap energy than the usual yellow scheelite monoclinic BiVO4 as well as a higher (more negative) conduction band than H(+)/H2 potential [0 VRHE (reversible hydrogen electrode) at pH 7]. Hence, it can extract H2 from pure water by visible light-driven overall water splitting without using any sacrificial reagents. The density functional theory calculation indicates that In(3+)/Mo(6+) dual doping triggers partial phase transformation from pure monoclinic BiVO4 to a mixture of monoclinic BiVO4 and tetragonal BiVO4, which sequentially leads to unit cell volume growth, compressive lattice strain increase, conduction band edge uplift, and band gap widening.

Impact of Flow Differentials According to Cardiac and Respiratory Cycles on Three Types of Fontan Operation.

Few hemodynamic comparison studies on various types of Fontan operation have been reported. The objective of this study was to perform hemodynamic comparisons for flow size and volume in three types of Fontan operation: atriopulmonary connection (APC), lateral tunnel (LT), and extracardiac conduit (ECC). Forty patients with Fontan operation (8 with APC Fontan, 22 with LT Fontan, and 10 with ECC Fontan) were enrolled. Velocity time integral (VTI) and average peak velocity (APV) were assessed according to cardiac and respiratory cycles in SVC, IVC, hepatic vein, conduit, LPA, and RPA using direct intravenous Doppler echocardiography. During each cardiac cycle in APC, VTI and APV between inspiration and expiration did not show significant differences in SVC, IVC, HV, LPA, or RPA. During each cardiac cycle in LT and ECC, VTI and APV between inspiration and expiration showed significant differences in all native vessels. The gap between S and D wave in APC was the highest, followed by that in LT. It was the lowest in ECC regardless of inspiration or expiration. Hepatic reverse VTI and APV in APC showed significant decreases compared to those in VC and PA during inspiration and expiration. Flow size and volume in APC were more influenced by cardiac cycle. Those in LT were moderately influenced by both respiratory cycle and cardiac cycle while those in ECC were more influenced by respiratory cycle. APC Fontan has hemodynamic inefficiency with prominent reverse flow. However, total cavopulmonary connection (TCPC) Fontan has more hemodynamic efficiency without prominent reverse flows.

The Role of Pharmacomechanical Endovascular Intervention for Iliofemoral Vein Thrombosis Compared to Conventional Anticoagulation Therapy.

Although anticoagulation therapy is the primary treatment for deep vein thrombosis (DVT), it has not been associated with the rapid recanalization of the venous occlusion. Moreover, it is associated with long-term disability due to post-thrombotic syndrome (PTS). In contrast, pharmacomechanical endovascular intervention (PMI) results in more rapid clinical improvement in DVT patients, but there are few reports on its long-term outcomes. This retrospective study evaluated the clinical effectiveness of PMI compared to conventional anticoagulation therapy (ACA) for acute and subacute iliofemoral DVT. We reviewed the medical records of 102 patients with iliofemoral DVT. A total of 46 patients for ACA and 56 patients for PMI were enrolled. We analyzed the clinical differences between the PMI and ACA groups by comparing the clinical signs, residual DVT free-rate, and PTS-free rate. There were no statistically significant differences in the demographic characteristics and risk factors except age between the groups (age: ACA, 52.0 ± 18.0 years; PMI, 59.0 ± 17.0 years; P = 0.035). The 1-, 3-, and 5-year residual DVT-free rate (ACA = 84.7%, 71.6%, and 46.0%; PMI = 82.1%, 76.8%, and 76.8%, respectively; P = 0.235) was not significantly different. However, the 1-, 3-, and 5-year PTS-free rate was significantly different (ACA = 93.5%, 74.0%, and 55.7%; PMI = 92.9%, 90.0%, and 90.0%, respectively; P = 0.019). There was no significant difference in the rate of other complications. PMI showed a lower incidence of PTS during the follow-up period. Therefore, PMI should be considered as an effective therapeutic modality for patients with iliofemoral DVT.

Surface Functionalized Graphene Biosensor on Sapphire for Cancer Cell Detection.

Graphene has several unique physical, optical and electrical properties such as a two-dimensional (2D) planar structure, high optical transparency and high carrier mobility at room temperature. These make graphene interesting for electrical biosensing. Using a catalyst-free chemical vapor deposition (CVD) method, graphene film is grown on a sapphire substrate. There is a single or a few sheets as confirmed by Raman spectroscopy and atomic force microscopy (AFM). Electrical graphene biosensors are fabricated to detect large-sized biological analytes such as cancer cells. Human colorectal carcinoma cells are sensed by the resistance change of an active bio-functionalized graphene device as the cells are captured by the immobilized antibody surface. The functionalized sensors show an increase in resistance as large as ~20% of the baseline with a small number of adhered cells. This study suggests that the bio-functionalized electrical graphene sensors on sapphire, which is a highly transparent material, can potentially detect circulating tumor cells (CTCs) and monitor cellular electrical behavior while being compatible with fluorescence-based optical-detection bioassays.

Myocardial Layers Specific Strain Analysis for the Acute Phase of Infant Kawasaki Disease.

Recently, the prevalence of infant Kawasaki disease (KD) has increased. However, the myocardial functional analysis of infant KD can be difficult and rarely reported. The purpose of this study was to investigate layer specific myocardial strain analysis for better assessment of the acute period in infant KD. The study retrospectively reviewed the echocardiographic data of 25 infant patients with KD at the acute phase. With advanced imaging, pulsed tissue Doppler velocity data, myocardial strain with three layers specific analysis was performed. Then the data were compared with 25 age-matched healthy control infants. The measures of longitudinal strain and radial strain were decreased in infant KD compared to healthy controls. The circumferential strain was significantly decreased in infant KD at all three myocardial layers, especially in the endocardial layer (KD: -20.5 ± 6.4 % vs. CONTROL: -25.6 ± 7.6 %, endocardium, p = 0.00001; -14.6 ± 4.4 % vs. -18.1 ± 4.0 %; middle myocardium, p = 0.01; -9.7 ± 3.3 % vs. -11.4 ± 3.8 %; epicardium, p = 0.04). The acute phase of infant KD demonstrated decreased myocardial strain measurement. Circumferential strain was the lowest in the endocardial layer. Further continuous long-term follow up for myocardial assessment should be recommended even after recovery with appropriate treatment.

Gap junction remodelling by chronic pressure overload is related to the increased susceptibility to atrial fibrillation in rat heart.

AIMS: Left atrial (LA) fibrosis caused by various pathological stimuli is a common finding. However, the difference of atrial remodelling via haemodynamic change in diverse cardiomyopathy has not been elucidated. METHODS AND RESULTS: Male Sprague-Dawley rats (6-8 weeks, n = 180) were randomly assigned to three groups and corresponding sham control groups: (i) ischaemic cardiomyopathy, (ii) left ventricular hypertrophy (LVH), and (iii) dilated cardiomyopathy. At 12 weeks after operation, atrial fibrillation (AF) inducibility and duration were assessed by in vivo burst transoesophageal pacing. Using the Langendorff apparatus, left ventricular (LV) function and pressure were measured. The expression of connexin-43 (Cx43) and alpha-smooth muscle actin (α-SMA) in atrial tissues was assessed by quantitative real-time polymerase chain reaction and immunohistochemical staining. Fibrosis was analysed by Masson's trichrome staining. Compared with controls, the LA weight/heart weight ratio was increased in the LVH group alone, and was significantly correlated with AF duration (P < 0.001, R = 0.388). Atrial fibrillation inducibility and duration were higher and longer only in the LVH group (P = 0.002, 0.079, respectively), and isolated LV diastolic dysfunction and elevated LV pressure were observed. Although α-SMA expression and fibrosis were increased in all three cardiomyopathy models, down-regulation of Cx43 expression in the LA was observed in the LVH group alone. CONCLUSION: Chronic pressure overload in the absence of LV systolic dysfunction resulted in LA hypertrophy and increased susceptibility to AF, which might be related to conduction abnormality via decreased expression and lateral distribution of Cx43 as well as interstitial fibrosis.