Search

BackgroundAmong the several musculoskeletal manifestations in patients with Marfan syndrome, spinal deformity causes pain and respiratory impairment and is a great hindrance to patients’ daily activities. The present study elucidates the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome.MethodsWe retrospectively evaluated 278 patients with pathogenic or likely pathogenicFBN1variants. The patients were divided into those with (n=57) or without (n=221) severe scoliosis. Severe scoliosis was defined as (1) patients undergoing surgery before 50 years of age or (2) patients with a Cobb angle exceeding 50° before 50 years of age. The variants were classified as protein-truncating variants (PTVs), which included variants creating premature termination codons and inframe exon-skipping, or non-PTVs, based on their location and predicted amino acid alterations, and the effect of theFBN1genotype on the development of severe scoliosis was examined. The impact of location ofFBN1variants on the development of severe scoliosis was also investigated.ResultsUnivariate and multivariate analyses revealed that female sex, PTVs ofFBN1and variants in the neonatal region (exons 25–33) were all independent significant predictive factors for the development of severe scoliosis. Furthermore, these factors were identified as predictors of progression of existing scoliosis into severe state.ConclusionsWe elucidated the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome. Patients harbouring pathogenicFBN1variants with these genetic risk factors should be monitored carefully for scoliosis progression.

BackgroundMarfan syndrome (MFS), an inherited disorder caused byFBN1gene mutations, causes fatal aortic aneurysm. Selective angiotensin II (Ang II) type 1 (AT1) receptor blockade is a preventive option for patients with MFS aortopathy, and recent clinical studies demonstrated that the inhibitory effect of an AT1receptor blocker (ARB) losartan on aortic aneurysm growth is equivalent to that of β-blockers. At present, several ARBs are clinically available, and they have drug-specific differences in pharmacological properties. Especially, inverse agonism of ARBs has potential benefits for cardiovascular protection, but its impact on MFS aortopathy remains poorly understood.MethodsCandesartan-7H is a candesartan derivative which lacks the carboxyl group critical for inverse agonist activity and works as a neutral antagonist for AT1receptor. Candesartan cilexetil (1 mg/kg/day), candesartan-7H (1 mg/kg/day or 20 mg/kg/day), or vehicle was administered toFbn1C1041G/+mice, and aortic aneurysm formation was analyzed using echocardiography, histological staining, andin situMMP assay. Activation of TGF-β signaling and mechanosensitive signaling was studied using western blot and immunohistochemical analysis.ResultsCandesartan cilexetil (1 mg/kg/day) and candesartan-7H (20 mg/kg/day) lowered blood pressures equally inFbn1C1041G/+mice, but that candesartan-7H (1 mg/kg/day) did not. Aortic aneurysmal progression in association with aortic wall thickening, degeneration of elastic fibers, deposition of collagen, MMP activation, and TGF-β signaling activation inFbn1C1041G/+mice was significantly suppressed by treatment with candesartan cilexetil (1 mg/kg/day), but not by candesartan-7H even at 20 mg/kg/day. In addition, candesartan cilexetil, but not candesartan-7H, inhibited up-regulation of mechanical stress–responsive transcriptional factor Egr-1 in ascending aorta ofFbn1C1041G/+mice.ConclusionsOur findings support a crucial role of inverse agonist activity of ARB for prevention of mechanical stress-induced AT1receptor activation and aortic aneurysm formation in MFS mice.

Background: Axitinib is a tyrosine kinase inhibitor (TKI) that inhibits vascular endothelial growth factor receptor signaling and is approved for second-line treatment of advanced renal cell carcinoma (RCC). Although the occurrence of hypertension with axitinib use has been documented, it is unclear whether a first-line TKI regimen can significantly affect the development of hypertension when axitinib is used as second-line therapy. Methods and Results: In this single-center retrospective study, advanced RCC patients treated with axitinib after first-line chemotherapy were divided into 2 groups according to the use of TKIs as part of first-line treatment before the initiation of axitinib. Clinical outcomes were compared between patients who were treated with (TKI(+); n=11) or without (TKI(-); n=11) a TKI. Although 63.6% of all patients had hypertension at baseline, axitinib-induced hypertension developed in 81.8% of patients, and 36.4% of patients experienced Grade 3 hypertension. After initiation of axitinib, both systolic and diastolic blood pressures and the hypertension grade were significantly elevated both in the TKI(+) and TKI(-) groups, and the number of antihypertensive drugs was significantly increased among all patients. Conclusions: This study suggests the need for proper monitoring and management of blood pressure in RCC patients treated with axitinib, regardless of a prior regimen with or without TKIs.

STUDY DESIGN A retrospective study of the prospective cohort. OBJECTIVE To demonstrate the accurate distribution of the severity of scoliosis in patients with Marfan syndrome, and to identify the predictive physical features for progression of scoliosis in Marfan syndrome. SUMMARY OF BACKGROUND DATA To date, no study has unveiled the risk factors for the progression of scoliosis in Marfan syndrome. METHODS We retrospectively obtained data from a prospective cohort of the Marfan syndrome clinic at our institute. We enrolled patients whose whole spine radiographs in the standing position were evaluated at the age of 15 or above, from January 2014 to March 2020. The collected variables were physical manifestations defined as in the systemic score of the revised Ghent nosology. We classified the degree of scoliosis into four categories: "not apparent," "mild" (10° ≤ Cobb < 25°), "moderate" (25° ≤ Cobb < 40°), and "severe" (40° ≤ Cobb or surgery conducted). To identify the risk factors for progression of scoliosis in Marfan syndrome, we conducted univariate and multivariate association analyses between severe scoliosis and each physical manifestation. RESULTS We identified 131 eligible patients (61 men and 70 women) with a mean age of 31.2 years. Scoliosis with a Cobb angle of ≥10° was identified in 116 patients (88.5%). Moderate scoliosis was identified in 33 patients (25.2%) and severe scoliosis in 53 patients (40.5%). The prevalence of each physical manifestation was equivalent to that reported in previous studies. Multivariate logistic regression analysis revealed that female sex (odds ratio, 3.27) and positive wrist sign (4.45) were predictive factors for progression of scoliosis into severe state in patients with Marfan syndrome. CONCLUSIONS The present study demonstrated the accurate distribution of the severity of scoliosis and identified the predictive factors for progression of scoliosis in patients with Marfan syndrome.Level of Evidence: 3.

Balloon pulmonary angioplasty (BPA) has been recognized as an alternative therapeutic approach for patients with inoperative chronic thromboembolic pulmonary hypertension and those with residual pulmonary hypertension after pulmonary endarterectomy. However, the safe and successful treatment rate for a total occlusion lesion (TOL) using BPA is low, mainly because vessels distal to the occlusion are invisible by angiogram. Here, we present the case of a 53-year-old woman with chronic thromboembolic pulmonary hypertension with successfully recanalization of a TOL by use of BPA with the aid of intracardiac echocardiography. The intracardiac echocardiography–assisted wire passage technique may be a promising method for safe and reliable TOL treatment using BPA.

Many patients with atrial septal defects (ASD) are asymptomatic and undiagnosed during the first few decades of life, but have overt heart failure, arrhythmias, cerebral infarction, and increased mortality in adults with advancing age. To provide a non-invasive, easy-to-use, and effective method for detecting ASD, we aimed to develop and validate a deep learning-based algorithm to diagnose ASD on chest radiographs. The ASD dataset was created from 173 chest radiographs of 74 patients with ASD and 170 chest radiographs of 100 patients without ASD. Convolutional neural network models (VGG16, ResNet50, DenseNet121, and Xception) for diagnosing ASD were pretrained using two different datasets, the large-scale real-world ImageNet dataset and the ChestX-ray14 dataset released by National Institutes of Health, followed by a round of training using the training set of the ASD dataset. Model performance was evaluated by five-fold stratified cross-validation. The best performance in ImageNet pretraining was achieved by ResNet50 model, and the cross-validation area under the curve (AUC) was 0.95, with sensitivity of 0.86, specificity of 0.87, and overall accuracy of 0.87. The best performance in ChestX-ray pretraining was achieved by Xception, and the cross-validation AUC was 0.93, with sensitivity of 0.85, specificity of 0.85, and overall accuracy of 0.85. The diagnostic performances of these models were comparable to those of cardiologists. Gradient-weighted Class Activation Mapping showed that the ImageNet-pretrained model focused on bilateral hilar regions, while the ChestX-ray14-pretrained model focused on areas around cardiac silhouette and lower lung fields. Our deep learning-based algorithms made a diagnosis of ASD on the input chest radiographs with high accuracy, and had potential to help clinicians make accurate diagnosis of ASD from routine chest radiography, leading to improvement of prognosis and quality of life in patients with ASD.

Marfan syndrome (MFS) is an inherited connective tissue disorder caused by mutations in the FBN1 gene encoding fibrillin-1, a matrix component of extracellular microfibrils. The main cause of morbidity and mortality in MFS is thoracic aortic aneurysm and dissection, but the underlying mechanisms remain undetermined. We found a significant increase in reactive oxygen species (ROS) generation in ascending aorta of MFS patients and MFS mice harboring the Fbn1 mutation (C1039G), which was associated with up-regulation of xanthine oxidoreductase (XOR) protein in aortic endothelial cells (ECs). Mechanosensitive signaling involving focal adhesion kinase (FAK)-p38 mitogen-activated protein kinase (MAPK) and early growth response-1 (Egr- 1) was aberrantly activated in ascending aorta of Fbn1C1039G/+ mice, and mechanical stress on human aortic ECs up-regulated XOR expression through FAK-p38 MAPK activation and Egr-1 up-regulation. Inhibition of XOR function by ECs-specific disruption of Xdh gene or by systemic administration of XOR inhibitor febuxostat in Fbn1C1039G/+ mice suppressed ROS generation, FAK-p38 MAPK activation, and Egr-1 up-regulation, leading to attenuation of aortic aneurysm formation. These findings unveil aberrant mechanosensitive signaling in vascular ECs triggering endothelial XOR activation and ROS generation as a culprit underlying the pathogenesis of aortic aneurysm formation in MFS, and highlight a drug repositioning approach using a uric acid lowering drug febuxostat as a potential therapy for MFS.

Hydathode is a plant tissue of vascular plants involved in water release called guttation. Arabidopsis hydathodes are found at the tips of leaf teeth and contain three major components: water pores, xylem ends, and small cells. Leaf teeth are known as the main parts for auxin biosynthesis and accumulation during leaf development. However, the detailed spatiotemporal relationship between auxin dynamics and hydathode development is unknown. In this study, we show that auxin biosynthesis and accumulation precede hydathode development. A triple marker line (called YDE line) containing three leaf tooth markers: YUC4:nls-3xGFP (auxin biosynthesis), DR5rev:erRFP (auxin accumulation or maxima), and E325-GFP (hydathode development), was generated, and spatiotemporal confocal microscopic analysis was carried out. The expression area of these markers became larger during leaf development, implying that the hydathode size enlarges as the leaf tooth grows. Detailed observation revealed that the auxin-related markers YUC4:nls-GFP and DR5rev:erRFP were first expressed in the early stage of leaf tooth growth. Then, E325-GFP was expressed partly overlapping with the auxin markers at a later stage. These findings provide new insights into the spatiotemporal relationship between auxin dynamics and hydathode development in Arabidopsis.

Among the several musculoskeletal manifestations in patients with Marfan syndrome, spinal deformity causes pain and respiratory impairment and is a great hindrance to patients' daily activities. The present study elucidates the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome.We retrospectively evaluated 278 patients with pathogenic or likely pathogenicUnivariate and multivariate analyses revealed that female sex, PTVs ofWe elucidated the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome. Patients harbouring pathogenic

Background Implantable continuous-flow left ventricular assist device (LVAD) improve renal function in advanced heart failure. However, the long-term effects of LVAD on renal function have not been investigated thoroughly. We aimed to assess long-term renal function in patients with LVAD support and to identify predictors for late deterioration in renal function (LDRF). Methods One hundred patients underwent LVAD implantation as a bridge to transplant at the University of Tokyo Hospital between May 2011 and December 2018. We assessed renal function at intervals (preoperative, 1, 6, 12, 18, 24 and 30 months after LVAD implantation). We divided patients into two groups: “with LDRF,” whose renal function at 30 months had decreased by >25% compared with preoperatively (n = 14), and “without LDRF” (n = 55). Results Renal function improved at 1 month, returned to preoperative levels at 6 months, and remained there up to 30 months after LVAD implantation. However, renal function impairment became evident in patients with LDRF 18 months after LVAD implantation. A ratio of right atrial pressure/pulmonary artery wedge pressure > 0.57 and left ventricular dimension diastole ≤ 67 mm were preoperative independent risk factors for LDRF. In addition, the incidence of perioperative acute kidney injury, ventricular arrhythmia, aortic insufficiency, and late right ventricular failure was significantly higher in patients with LDRF. Conclusion LDRF after LVAD implantation corresponded to several risk factors, including a small left ventricle and LVAD-related complications, such as right ventricular failure.

Loeys–Dietz syndrome (LDS) is caused by variants of transforming growth factor-β (TGF-β)-related genes and is characterized by aortic aneurysm and dissection. We report an LDS patient with a de novo missense variant of TGFBR1 [c.1126A>G, p.(Lys376Glu)] in which active TGF-β signaling was observed in the aorta, despite the in vitro demonstration that the loss-of-function mutation lies within the serine/threonine kinase domain. The mechanism underlying this TGF-β paradox in LDS aortopathy should be further investigated.

Introduction Short-chain fatty acids are one of the gut microbial metabolites that may influence host physiology. We previously reported that gut dysbiosis was associated with heart failure, and that the proportions of butyrate-producing bacteria diminished prominently in the gut of patients with heart failure. Purpose We investigated the molecular mechanism of butyrate and investigated the protective mechanism against heart failure. Methods We searched for G protein-coupled receptors for short-chain fatty acids using single-cell transcriptome analysis of cardiomyocytes and non-cardiomyocytes isolated from murine hearts. In addition, we examined the effects of butyrate on endothelin-1 (ET1) or isoproterenol-induced hypertrophic responses and histone deacetylase (HDAC) activities in cultured neonatal rat cardiomyocytes. Results Single-cell transcriptome analysis and co-expression network analysis revealed that G protein-coupled receptors for short-chain fatty acid receptors were not expressed in cardiomyocytes and that Olfr78 was expressed in vascular smooth muscle cells in the heart. Treatment with butyrate inhibited ET1-induced hypertrophic growth and up-regulation of the genes such as Nppa, Acta1, and Myh7 in cultured rat neonatal cardiomyocytes. Moreover, butyrate increased the acetylation levels of histone H3, indicating that butyrate has an inhibitory effect on HDAC in cardiomyocytes. In addition, treatment with butyrate caused up-regulation of Inpp5f, encoding inositol polyphosphate-5-phosphatase f, which was associated with a significant decrease in the phosphorylation levels of Akt. These results suggest that butyrate may act as HDAC inhibitor to increase Inpp5f gene expression, leading to the activation of Akt-glycogen synthase kinase 3beta (Gsk3beta) pathway, and thereby protect against hypertrophic responses. Conclusion There was no known GPCR for short-chain fatty acid expressed in cardiomyocytes. However, butyrate suppressed cardiomyocyte hypertrophy through epigenetic modification of gene expression. Our results may uncover a potential role of the dysbiosis of intestinal microbiota in the pathogenesis of cardiac hypertrophy and failure. Funding Acknowledgement Type of funding source: None

Hydathodes are typically found at leaf teeth in vascular plants and are involved in water release to the outside. Although morphological and physiological analysis of hydathodes has been performed in various plants, little is known about the genes involved in hydathode function. In this study, we performed fluorescent protein-based imaging and tissue-specific RNA-seq analysis in Arabidopsis hydathodes. We used the enhancer trap line E325, which has been reported to express green fluorescent protein (GFP) at its hydathodes. We found that E325-GFP was expressed in small cells found inside the hydathodes (named E cells) that were distributed between the water pores and xylem ends. No fluorescence of the phloem markers pSUC2:GFP and pSEOR1:SEOR1-YFP was observed in the hydathodes. These observations indicate that Arabidopsis hydathodes are composed of three major components: water pores, xylem ends, and E cells. In addition, we performed transcriptome analysis of the hydathode using the E325-GFP line. Microsamples were collected from GFP-positive or -negative regions of E325 leaf margins with a needle-based device (~130 µm in diameter). RNA-seq was performed with each single microsample using a high-throughput library preparation method called Lasy-Seq. We identified 72 differentially expressed genes. Among them, 68 genes showed significantly higher and four genes showed significantly lower expression in the hydathode. Our results provide new insights into the molecular basis for hydathode physiology and development.

Tracking and analyzing the behaviors of living organisms are important for understanding neural activity at the moment of specific movement. To obtain reliable tracking data for the target motion, detection accuracy is critical. In this study, we compared deep learning and template matching, for their utility in mouse snout tracking, with a particular focus on detection accuracy. Comparison of the detection errors generated by each method using 10 different videos offered detailed insight into the efficacy of each method for this purpose.

Increased transforming growth factor-β (TGF-β) signaling contributes to the pathophysiology of aortic aneurysm in Marfan syndrome (MFS). Recent reports indicate that a small but significant number of inflammatory cells are infiltrated into the aortic media and adventitia in MFS. However, little is known about the contribution of myeloid cells to aortic aneurysmal formation. In this study, we ablated the TGF-β type II receptor geneTgfbr2in myeloid cells ofFbn1C1039G/+MFS mice (Fbn1C1039G/+;LysM-Cre/+;Tgfbr2fl/flmice, hereinafter calledFbn1C1039G/+;Tgfbr2MyeKO) and evaluated macrophage infiltration and TGF-β signaling in the aorta. Aneurysmal formation with fragmentation and disarray of medial elastic fibers observed in MFS mice was significantly ameliorated inFbn1C1039G/+;Tgfbr2MyeKOmice. In the aorta ofFbn1C1039G/+;Tgfbr2MyeKOmice, both canonical and noncanonical TGF-β signals were attenuated and the number of infiltrated F4/80-positive macrophages was significantly reduced.In vitro, TGF-β enhanced the migration capacity of RAW264.7 macrophages. These findings suggest that TGF-β signaling in myeloid cells promotes aortic aneurysmal formation and its inhibition might be a novel therapeutic target in MFS.

Background: Marfan syndrome can cause life-threatening aortic complications. We investigated the relationship between FBN1 genotype and severe aortopathy (aortic root replacement, type A dissections, and related death). Methods: We evaluated 248 patients with pathogenic or likely pathogenic FBN1 variants. The variants were classified as haploinsufficient type (HI, n=93) or dominant-negative type (DN, n=155) based on their location and predicted amino acid alterations, and we examined the effects of the FBN1 genotype on severe aortic events (aortic root replacement, type A dissections, and related death). RESULTS: The cumulative event-free probability was significantly lower in the HI group than in the DN group (adjusted hazard ratio, 2.1; 95% confidence interval, 1.4 -3.2; P Conclusions: DN-CD+HI patients should be monitored more carefully than DN-nonCD patients for rapid development of aortic root aneurysms.

Marfan syndrome can cause life-threatening aortic complications. We investigated the relationship betweenWe evaluated 248 patients with pathogenic or likely pathogenicThe cumulative event-free probability was significantly lower in the HI group than in the DN group (adjusted hazard ratio, 2.1; 95% confidence interval, 1.4 -3.2;DN-CD+HI patients should be monitored more carefully than DN-nonCD patients for rapid development of aortic root aneurysms.

Congenital contractural arachnodactyly (CCA) is a rare connective tissue disorder characterized by marfanoid habitus with camptodactyly. However, cardiac features have rarely been documented in adults. We herein report a sporadic case of CCA in a 20-year-old woman who developed decompensated dilated cardiomyopathy. The patient did not have any mutations in the FBN1 or FBN2 genes, which are most commonly associated with Marfan syndrome and CCA, respectively. Although whether these two diseases are caused by a mutation(s) in the same gene or two different genes remains unknown, this case provides new clinical insight into the cardiovascular management of CCA.

Background— Balloon pulmonary angioplasty (BPA) has become an alternative therapy for patients with chronic thromboembolic pulmonary hypertension who are ineligible for pulmonary endarterectomy. We retrospectively investigated intravascular ultrasound measurements to elucidate how the lumen enlarges immediately after BPA. Methods and Results— A total of 326 lesions in 71 patients with chronic thromboembolic pulmonary hypertension were analyzed. The cross-sectional areas (CSAs) of the external elastic membrane and lumen measured by intravascular ultrasound before and after BPA were assessed for each lesion type (type A, ring-like stenosis lesions; type B, web lesions; type C, subtotal occlusion lesions). Comparing the lesion types, the proportion of the area occupied by fibrous tissue was smallest in the type A lesions and largest in the type C lesions. The mean lesion lumen CSA was increased after BPA because of an increase in external elastic membrane CSA (from 23.2±12.9 to 27.2±14.3 mm 2 ; P 2 ; P r 2 =0.762; P Conclusions— Lumen enlargement immediately after BPA was obtained by the overall vessel expansion induced by a stretch of the arterial wall. In addition, the amount of fibrous tissue depended on each lesion type. Thus, it might be beneficial to change the balloon size to correspond with the lesion type.

Variants in TGFBR1 have been reported to induce two completely distinct diseases, namely Loeys–Dietz syndrome (LDS) and multiple self-healing squamous epithelioma (MSSE). However, detailed mechanisms underlying this effect remain unknown. We report a Japanese familial case of LDS with a novel splice donor site variant in TGFBR1 gene (c.973 + 1 G > A; NG_007461.1). The intronic variant was predicted to mediate in-frame exon 5 skipping within the serine/threonine kinase (STK) domain, which may also be mediated by a similar TGFBR1 variant of a splice acceptor site in intron 4 (c.806-2 A > C), identified in a British familial case of MSSE. Therefore, ex vivo splicing and functional assays were performed in mammalian cells to evaluate the effect of these sequence variants. The MSSE variant activated a cryptic acceptor site at 76 bp downstream of the 3′ natural splice acceptor site, which produced an out-of-frame transcript (r.807_882del, p.Asn270Thrfs*8). In contrast, the LDS variant generated two types of in-frame transcription products, r.[806_973del, 965_973 del], and produced two functionally inactivated proteins, p.[Asp269_Gln324del, Thr323_Gly325del], as a result of exon 5 skipping and the activation of a cryptic donor splice site at 9 bp upstream of the 5′ natural splice donor site, respectively. Our results support the previously proposed but not yet approved mechanism that dominant-negative and truncating variants in STK domain induce LDS and MSSE, respectively.

Marfan syndrome (MFS) is an autosomal dominant heritable disorder of connective tissue that affects the cardiovascular, skeletal, ocular, pulmonary, and nervous systems and is usually caused by mutations in the FBN1 gene, which encodes fibrillin-1. MFS is traditionally considered to result from the structural weakness of connective tissue. However, recent investigations on molecular mechanisms indicate that increased transforming growth factor-β (TGF-β) activity plays a crucial role in the pathogenesis of MFS and related disorders, such as Loeys-Dietz syndrome (LDS), which is caused by mutation in TGF-β signaling-related genes. In addition, recent studies show that angiotensin II type 1 receptor (AT1R) signaling enhances cardiovascular pathologies in MFS, and the angiotensin II receptor blocker losartan has the potential to inhibit aortic aneurysm formation. However, the relationship between TGF-β and AT1R signaling pathways remains poorly characterized. In this review, we discuss the recent studies on the molecular mechanisms underlying cardiovascular manifestations of MFS and LDS and the ensuing strategies for management.

Gitelman's syndrome (GS) is an autosomal recessive disorder; it is rarely inherited over several generations. A 16-year-old boy showed hypokalemia and hypocalciuria. Clinically, he was diagnosed as GS because of diuretic responsiveness to furosemide but not thiazide. Genetic testing disclosed he was a compound heterozygote (T180K/V677M) for the SLC12A3 gene. Unexpectedly, the patient's father also showed hypokalemia and hypocalciuria. The genetic analysis showed he had an L849H mutation in addition to T180K. The present pedigree showed an extremely rare case. Diuretic tests are useful diagnostic methods, and genetic testing is necessary for precise evaluation of complicated cases as in this family.