Angpt1 binding to Tie1 regulates the signaling required for lymphatic vessel development in zebrafish.

Development of the vascular system is regulated by multiple signaling pathways mediated by receptor tyrosine kinases. Among them, angiopoietin (Ang)/Tie signaling regulates lymphatic and blood vessel development in mammals. Of the two Tie receptors, Tie2 is well known as a key mediator of Ang/Tie signaling, but, unexpectedly, recent studies have revealed that the Tie2 locus has been lost in many vertebrate species, whereas the Tie1 gene is more commonly present. However, Tie1-driven signaling pathways, including ligands and cellular functions, are not well understood. Here, we performed comprehensive mutant analyses of angiopoietins and Tie receptors in zebrafish and found that only angpt1 and tie1 mutants show defects in trunk lymphatic vessel development. Among zebrafish angiopoietins, only Angpt1 binds to Tie1 as a ligand. We indirectly monitored Ang1/Tie1 signaling and detected Tie1 activation in sprouting endothelial cells, where Tie1 inhibits nuclear import of EGFP-Foxo1a. Angpt1/Tie1 signaling functions in endothelial cell migration and proliferation, and in lymphatic specification during early lymphangiogenesis, at least in part by modulating Vegfc/Vegfr3 signaling. Thus, we show that Angpt1/Tie1 signaling constitutes an essential signaling pathway for lymphatic development in zebrafish.

Cardiac forces regulate zebrafish heart valve delamination by modulating Nfat signaling.

In the clinic, most cases of congenital heart valve defects are thought to arise through errors that occur after the endothelial-mesenchymal transition (EndoMT) stage of valve development. Although mechanical forces caused by heartbeat are essential modulators of cardiovascular development, their role in these later developmental events is poorly understood. To address this question, we used the zebrafish superior atrioventricular valve (AV) as a model. We found that cellularized cushions of the superior atrioventricular canal (AVC) morph into valve leaflets via mesenchymal-endothelial transition (MEndoT) and tissue sheet delamination. Defects in delamination result in thickened, hyperplastic valves, and reduced heart function. Mechanical, chemical, and genetic perturbation of cardiac forces showed that mechanical stimuli are important regulators of valve delamination. Mechanistically, we show that forces modulate Nfatc activity to control delamination. Together, our results establish the cellular and molecular signature of cardiac valve delamination in vivo and demonstrate the continuous regulatory role of mechanical forces and blood flow during valve formation.

Long-term results of etiology-based thoracic endovascular aortic repair: a single-center experience.

The use of thoracic endovascular aortic repair (TEVAR) for thoracic aortic aneurysm (TAA) and Stanford type B aortic dissection (TBAD) has been increasing; however, in terms of etiology, the differences of long term after TEVAR outcomes remain unexplored. Thus, we investigated etiology-specific long-term results of TEVAR for TAA and TBAD. A total of 421 TEVAR procedures were performed at our institution from July 2007 to December 2021; 249 TAA cases and 172 TBAD cases were included. Traumatic aortic dissection and aortic injury cases were excluded. The mean observation duration was 5.7 years. The overall 30-day mortality rate was 1.4% (n = 6), with 1.2% (n = 3) in the TAA group and 1.7% (n = 3) in the TBAD group. The overall incidence of postoperative stroke was 0.9% (n = 4), with 1.2% (n = 3) and 0.6% (n = 1) in the TAA and TBAD groups, respectively (p = 0.90). Paraplegia developed in 1.7% (n = 7) of patients, with 2.4% (n = 6) in the TAA group and 0.6% (n = 1) in the TBAD group. Freedom from aortic-related death was not significantly different between the two etiologies; however, thoracic reintervention was more common in the TBAD group (p = 0.003), with endoleak being the most common indication for reintervention. Additionally, retrograde type A aortic dissection occurred in four TBAD cases, while migration occurred in three TAA cases. The perioperative results of TEVAR for TAA and TBAD were satisfactory. The long-term results were unfavorable owing to the occurrence of etiology-specific and common complications. In terms of the high frequency of reintervention, the long-term complications associated with TEVAR are etiology specific.

Mid- and long-term results of open repair for chronic type B aortic dissection in endovascular era.

Medical management is the standard treatment of chronic type B aortic dissection (CTBAD). However, the roles of open surgical repair (OSR) and thoracic endovascular repair (TEVAR) in patients with CTBAD remain controversial. Thus, this study aimed to assess and compare the mid- and long-term clinical outcomes of OSR via left thoracotomy with that of TEVAR for CTBAD. The data of 85 consecutive patients who underwent surgery for CTBAD from April 2007 to May 2021 were retrospectively reviewed. The patients were divided into two groups: Group G, which included patients who underwent OSR, and Group E, which included patients who underwent TEVAR. Groups G and E comprised 33 and 52 patients, respectively. Preoperative and postoperative computed tomography (CT) studies were retrospectively analyzed for the maximum diameter. The mean duration of the follow-up period was 5.8 years. Operative mortality did not occur. There was no difference in complications, such as stroke (G: 2 vs. E: 0, p = 0.30), paraplegia (G: 1 vs. E: 1, p = 0.66), and respiratory failure (G: 2, vs. E: 0, p = 0.30). The difference in preoperative factors was observed, including the intervals between onset and operation (G; 4.9 years vs. E; 1.9 years, p < 0.01), maximum diameter in preoperative CT (G; 59.0 mm vs. E; 50.5 mm, p < 0.001), and maximum false lumen diameter (G; 35.5 mm vs. E; 29.0 mm, p < 0.01). There was no significant difference in the mid- and long-term survival rates (p = 0.49), aorta-related deaths (p = 0.33), and thoracic re-intervention rates (p = 0.34). Postoperative adverse events occurred in Group E: four cases of retrospective type A aortic dissection, two cases of aorto-bronchial fistula, and one case of aorto-esophagus fistula. Aorta-related death and re-intervention rates crossed over in both groups after seven years postoperatively. Although endovascular repair of CTBAD is less invasive, the rate of freedom from re-intervention was unsatisfactory. Some fatal complications were observed in the endovascular group, and the mid- and long-term outcomes were reversed compared with those in the OSR group. Although OSR is an invasive procedure, it could be performed safely without perioperative complications. OSR has more feasible mid- and long-term outcomes.

[One Debranch Thoracic Endovascular Aortic Repair for Saccular Aortic Aneurysm in the Long Term of Ductus Arteriosus Closure].

We present the case of 60s male who underwent ductus arteriosus closure at the age of 10. He presented with hoarseness and a 25 mm-sized saccular aortic aneurysm was identified at the site of the closed ductus through the computed tomography( CT). The patient successfully underwent 1-debranch thoracic endovascular aortic repair resulting in improved hoarseness. While rare, several reports have documented aneurysm formation long after ductus arteriosus closure. Recent studies highlight favorable outcomes with endovascular repair. Despite its rarity, aneurysmal formation after ductus closure remains a serious complication. Given the increasing population of patients with prior ductus arteriosus closure and the discontinuation of long-term follow-up, awareness of the complication of aneurysmal formation is crucial. Not only congenital cardiologists but also general physicians should consider this differential diagnosis for patients presenting with symptoms such as hoarseness or back pain and a history of ductus closure.

Fenestrated Fontan-like circulation under durable left-ventricular assist device support in fulminant myocarditis.

Fulminant myocarditis is a fatal development from profound biventricular heart failure and often requires both right- and left-ventricular assistance to maintain hemodynamics, even at the risk of increased mortality and morbidity. Here, we present a 42-year-old female with profound biventricular failure due to fulminant myocarditis, resolved by an isolated durable left-ventricular assist device support under a fenestrated, Fontan-like circulation and managed low-pulmonary vascular resistance.

Concomitant Mitral Regurgitation in Severe Aortic Stenosis　- A Report From the CURRENT AS Registry.

BACKGROUND: The clinical significance of concomitant mitral regurgitation (MR) has not been well addressed in patients with severe aortic stenosis (AS).Methods and Results:We analyzed 3,815 patients from a retrospective multicenter registry of severe AS in Japan (CURRENT AS registry). We compared the clinical outcomes between patients with moderate/severe MR and with none/mild MR according to the initial treatment strategy (initial aortic valve replacement [AVR] or conservative strategy). The primary outcome measure was a composite of aortic valve-related death or heart failure hospitalization. At baseline, moderate/severe MR was present in 227/1,197 (19%) patients with initial AVR strategy and in 536/2,618 (20%) patients with a conservative strategy. The crude cumulative 5-year incidence of the primary outcome measure was significantly higher in patients with moderate/severe MR than in those with none/mild MR, regardless of the initial treatment strategy (25.2% vs. 14.4%, P<0.001 in the initial AVR strategy, and 63.3% vs. 40.7%, P<0.001 in the conservative strategy). After adjusting confounders, moderate/severe MR was not independently associated with higher risk for the primary outcome measure in the initial AVR strategy (hazard ratio [HR] 1.11, 95% confidence interval [CI] 0.67-1.83, P=0.69), and in the conservative strategy (HR 1.13, 95% CI 0.93-1.37, P=0.22). CONCLUSIONS: Concomitant moderate/severe MR was not independently associated with higher risk for the primary outcome measure regardless of the initial treatment strategy.

Surgical outcomes of bridge-to-bridge therapy with extracorporeal left ventricular assist device for acute myocardial infarction in cardiogenic shock.

BACKGROUND: Extracorporeal left ventricular assist device is often required for acute myocardial infarction patients in cardiogenic shock when temporary mechanical circulatory support fails to provide hemodynamic stabilization. This study aimed to evaluate the clinical outcomes of acute myocardial infarction patients in cardiogenic shock supported by an extracorporeal left ventricular assist device. METHODS: This retrospective study enrolled 13 acute myocardial infarction patients in cardiogenic shock treated with an extracorporeal left ventricular assist device from April 2011 to July 2020. RESULTS: Twelve (92.3%) and eleven (84.6%) patients were supported using venoarterial extracorporeal membrane oxygenation and intra-aortic balloon pumping before implantation, respectively. The median duration from acute myocardial infarction to extracorporeal left ventricular assist device implantation was 7 (3.5-24.5) days. The overall in-hospital mortality rate was 30.8% (n = 4). Extracorporeal left ventricular assist device was explanted in one patient for cardiac recovery; eight (61.5%) patients were approved as heart transplant candidates in whom the extracorporeal left ventricular assist device was exchanged for a durable left ventricular assist device; two (15.4%) expired while waiting for a heart transplant, and two (15.4%) received a successful transplant. The 1- and 3-year overall survival rates after extracorporeal left ventricular assist device implantation were 68.3% and 49.9%, respectively. CONCLUSIONS: The operative mortality after extracorporeal left ventricular assist device implantation in acute myocardial infarction patients in cardiogenic shock was favorable. Our strategy of early hemodynamic stabilization with extracorporeal left ventricular assist device implantation in these patients as a bridge-to-bridge therapy was effective in achieving better survival.

Validity of Ipsilateral Internal Mammary Coronary Artery Bypass Graft of Arteriovenous Fistula.

BACKGROUND: In coronary artery bypass grafting (CABG) for haemodialysis patients, arteriovenous fistula can reduce blood flow from the internal mammary artery (IMA) graft. The purpose of this study was to delineate the rationale of ipsilateral IMA grafting to the arteriovenous fistula by assessing graft flow and patency. METHOD: The clinical records of 139 haemodialysis patients who underwent off-pump CABG, including IMA grafting to the left anterior descending artery (LAD) between April 2007 and December 2018, were retrospectively reviewed. Clinical outcomes and transit-time flowmetry results of IMA to LAD bypass grafts during off-pump CABG and postoperative angiography were examined. RESULTS: An ipsilateral IMA to the arteriovenous fistula (Ipsi-IMA) was used in 89 patients, and a contralateral IMA to the arteriovenous fistula (Contra-IMA) was used in 50 patients and no hospital deaths occurred. The mean graft flow and angiographic patency rate did not differ between the Ipsi-IMA and Contra-IMA groups. In patients with 51 to 90% stenosis of LAD, there was no significant difference in the mean graft flow. In comparison, in the patients with 91 to 100% stenosis of LAD, the mean graft flow in the Ipsi-IMA group was significantly lower than that in the Contra-IMA group (p=0.03). Kaplan-Meier analyses showed a 5-year survival rate of 57.6% for Ipsi-IMA and 64.8% for Contra-IMA (p=0.47). CONCLUSIONS: In the revascularisation of the LAD, the graft patency rate of the Ipsi-IMA was not inferior to that of the Contra-IMA. However, when the LAD has 91 to 100% stenosis, a Contra-IMA to arteriovenous fistula may be beneficial in terms of sufficient flow capacity.

In vivo analysis of cardiomyocyte proliferation during trabeculation.

Cardiomyocyte proliferation is crucial for cardiac growth, patterning and regeneration; however, few studies have investigated the behavior of dividing cardiomyocytes in vivo Here, we use time-lapse imaging of beating hearts in combination with the FUCCI system to monitor the behavior of proliferating cardiomyocytes in developing zebrafish. Confirming in vitro observations, sarcomere disassembly, as well as changes in cell shape and volume, precede cardiomyocyte cytokinesis. Notably, cardiomyocytes in zebrafish embryos and young larvae mostly divide parallel to the myocardial wall in both the compact and trabecular layers, and cardiomyocyte proliferation is more frequent in the trabecular layer. While analyzing known regulators of cardiomyocyte proliferation, we observed that the Nrg/ErbB2 and TGFß signaling pathways differentially affect compact and trabecular layer cardiomyocytes, indicating that distinct mechanisms drive proliferation in these two layers. In summary, our data indicate that, in zebrafish, cardiomyocyte proliferation is essential for trabecular growth, but not initiation, and set the stage to further investigate the cellular and molecular mechanisms driving cardiomyocyte proliferation in vivo.

Two-Year Results of the 17-mm Avalus Aortic Valve in the PERIGON Japan Trial.

BACKGROUND: The PERIcardial SurGical AOrtic Valve ReplacemeNt (PERIGON) Japan Trial was developed to assess the safety and effectiveness of the 17-mm Avalus bioprosthesis (Medtronic, Minneapolis, MN, USA) in patients undergoing surgical aortic valve replacement.Methods and Results:The primary endpoint in the trial was the percentage of patients achieving the composite of at least 1 class improvement in New York Heart Association (NYHA) functional class at 1 year compared with baseline and effective orifice area index (EOAI) of 0.6 cm2/m2or greater at 1-year after implantation, compared with a performance goal of 60%. The present study reports outcomes through 2 years. Eleven patients were implanted (10 [91%] female, median age 78.3 years). From baseline to 1 year, 10 subjects (91%) showed an improvement in NYHA classification. At 1 year, mean (±SD) EOAI was 0.82±0.17 cm2/m2, with 10 patients (91%) having an EOAI ≥0.6 cm2/m2. As such, 9 of 11 patients (82%) successfully met the primary endpoint. One death occurred between the 1- and 2-year follow-up visits, unrelated to the valve. There were no valve reinterventions, explants, or device deficiencies through 2 years. CONCLUSIONS: The PERIGON Japan Trial met its primary endpoint. Surgical implantation of the 17-mm Avalus aortic bioprosthesis can be performed with an acceptable incidence of device-related adverse events, and the valve performs effectively based on echocardiographic findings.

Early and mid-term results of transcatheter aortic valve implantation and valve durability assessment.

This study aimed to evaluate the early and mid-term outcomes of transcatheter aortic valve implantation (TAVI) and to assess valve durability. A total of 146 consecutive patients who underwent TAVI for severe aortic stenosis between October 2013 and August 2018 were retrospectively reviewed. All patients (mean age, 84 ± 6 years; age range 53-98 years; 42 males [28.7%]) had multiple comorbidities, with a mean logistic EuroSCORE of 30.9 ± 17.4%. Eighteen patients (12.3%) were aged 90 years or over. Five in-hospital deaths (3.4%) occurred, and 36 patients (24.7%) experienced major TAVI-related complications. With the transfemoral approach, 10 patients had major vascular complications, which mostly occurred with first-generation devices (n = 9) but less commonly with new-generation low-profile devices (P = 0.0078). During a follow-up period of 580 ± 450 (11-1738) days, 29 late deaths occurred. The survival rate was 86.0%, 78.0%, and 61.7% at 1, 2, and 3 years, respectively. Multivariate Cox hazard regression analysis revealed that more-than-moderate tricuspid regurgitation was the only independent risk factor for late deaths due to any cause (hazard ratio, 3.145; 95% confidence interval, 1.129-8.762; P = 0.0283). No statistically significant differences between post-TAVI before discharge from the hospital and at 4 years after TAVI were observed with respect to aortic valve area (1.76 ± 0.49 cm2 vs. 1.64 ± 0.38 cm2; P = 0.1871) and mean pressure gradient (10.0 ± 4.6 mmHg vs. 7.9 ± 3.3 mmHg; P = 0.5032). TAVI was a feasible method with acceptable early and mid-term outcomes and valve durability for at least 4 years in poor-risk patients. Further close follow-up is essential to evaluate late outcomes and valve durability.

Prognostic ability of mid-term worsening renal function after percutaneous coronary intervention: findings from the SHINANO registry.

Chronic kidney disease is a prognostic factor for cardiovascular disease. Worsening renal function (WRF), specifically, is an important predictor of mortality in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI). We evaluate the prognostic impact of mid-term WRF after PCI on future cardiovascular events. We examined the renal function data of 1086 patients in the first year after PCI using the SHINANO 5-year registry. Patients were divided into two groups, mid-term WRF and non-mid-term WRF, and primary outcomes were major adverse cardiovascular events (MACE) and death. Mid-term WRF was defined as an increase in creatinine (≥ 0.3 mg/dL) in the first year after PCI. Mid-term WRF was found in 101 patients (9.3%), and compared to non-mid-term WRF, it significantly increased the incidence of MACE (p < 0.001), and all-cause death (p < 0.001), myocardial infarction (p = 0.001). Furthermore, mid-term WRF patients had higher incidence of future heart failure (p < 0.001) and new-onset atrial fibrillation (p = 0.01). Patients with both mid-term WRF and chronic kidney disease had increased MACE compared to patients with either condition alone (p < 0.001). Similarly, patients with mid-term WRF and acute kidney injury had increased MACE compared to patients with either condition alone (p < 0.001). Multivariate Cox regression analysis revealed mid-term WRF as a strong predictor of MACE (hazard ratio: 2.50, 95% confidence interval 1.57-3.98, p < 0.001). Mid-term WRF after PCI negatively affects MACE, as well as future admission due to heart failure and new-onset atrial fibrillation, chronic kidney disease, and acute kidney injury.

Thoracic aortic mycotic aneurysm due to Staphylococcus argenteus: A case report.

Staphylococcus argenteus was subdivided as a novel species from Staphylococcus aureus in 2014. We herein report a case of mycotic aneurysm caused by S. argenteus. A 59-year-old woman with diabetes and schizophrenia visited at the emergency room because of falling. Chest computed tomography revealed a left humerus fracture and a thoracic aortic aneurysm. With her elevated WBC count and CRP level, she was suspected to have a mycotic aneurysm. After being transferred to our hospital, vascular graft replacement surgery was performed. Isolates of blood cultures and surgical specimens were identified as S. argenteus by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MAS MALDI Biotyper Ver. 8.0). Although S. argenteus lacks staphyloxanthin, a carotenoid pigment, it is coagulase positive. In addition to traditional and automated biochemical identification systems, even MALDI-TOF MAS may misidentify the organism as S. aureus depending on its version. S. argenteus should be considered when coagulase-negative Staphylococcus like colonies are obtained from samples of S. aureus infection. To our knowledge, this is the first case of aortic mycotic aneurysm caused by S. argenteus in Japan. Although S. argenteus is considered less virulent than Staphylococcus aureus, we should closely monitor the prevalence and the clinical impact of this pathogen on community-acquired infections and health care-associated infections.

Development of a High-Efficacy Reprogramming Method for Generating Human Induced Pluripotent Stem (iPS) Cells from Pathologic and Senescent Somatic Cells.

Induced pluripotent stem (iPS) cells are a type of artificial pluripotent stem cell induced by the epigenetic silencing of somatic cells by the Yamanaka factors. Advances in iPS cell reprogramming technology will allow aging or damaged cells to be replaced by a patient's own rejuvenated cells. However, tissue that is senescent or pathologic has a relatively low reprogramming efficiency as compared with juvenile or robust tissue, resulting in incomplete reprogramming; iPS cells generated from such tissue types do not have sufficient differentiation ability and are therefore difficult to apply clinically. Here, we develop a new reprogramming method and examine it using myofibroblasts, which are pathologic somatic cells, from patient skin tissue and from each of the four heart chambers of a recipient heart in heart transplant surgery. By adjusting the type and amount of vectors containing transcriptional factors for iPS cell reprogramming, as well as adjusting the transfection load and culture medium, the efficiency of iPS cell induction from aged patient skin-derived fibroblasts was increased, and we successfully induced iPS cells from myocardial fibroblasts isolated from the pathologic heart of a heart transplant recipient.

[Two-debranching Thoracic Endovascular Aortic Repair for Thoracic Aortic Aneurysm Complicated by Idiopathic Thrombocytopenic Purpura;Report of a Case].

Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disease in which the number of platelets decreases due to auto-antibodies against platelets. We report that thoracic endovascular aortic repair (TEVAR) was successfully performed for a thoracic aortic aneurysm complicated by ITP. The patient was a man of 77 years of age. He had a history of splenectomy due to ITP. He was admitted to our hospital with an aneurysm of the aortic arch that enlarged to a maximum minor axis of 63 mm. An operation was planned. Because of ITP, it was judged that replacement of the aortic arch using a cardio-pulmonary pump would be associated with a high risk of bleeding. Thus, 2-debranching TEVAR was selected and performed with no hemorrhagic complications. He was discharged from the hospital on the 12th day after surgery. We believe that 2-debranching TEVAR is effective for reducing perioperative bleeding in patients with ITP.

Clarification of mural cell coverage of vascular endothelial cells by live imaging of zebrafish.

Mural cells (MCs) consisting of vascular smooth muscle cells and pericytes cover the endothelial cells (ECs) to regulate vascular stability and homeostasis. Here, we clarified the mechanism by which MCs develop and cover ECs by generating transgenic zebrafish lines that allow live imaging of MCs and by lineage tracing in vivo To cover cranial vessels, MCs derived from either neural crest cells or mesoderm emerged around the preformed EC tubes, proliferated and migrated along EC tubes. During their migration, the MCs moved forward by extending their processes along the inter-EC junctions, suggesting a role for inter-EC junctions as a scaffold for MC migration. In the trunk vasculature, MCs derived from mesoderm covered the ventral side of the dorsal aorta (DA), but not the posterior cardinal vein. Furthermore, the MCs migrating from the DA or emerging around intersegmental vessels (ISVs) preferentially covered arterial ISVs rather than venous ISVs, indicating that MCs mostly cover arteries during vascular development. Thus, live imaging and lineage tracing enabled us to clarify precisely how MCs cover the EC tubes and to identify the origins of MCs.

Polydom Is an Extracellular Matrix Protein Involved in Lymphatic Vessel Remodeling.

RATIONALE: Lymphatic vasculature constitutes a second vascular system essential for immune surveillance and tissue fluid homeostasis. Maturation of the hierarchical vascular structure, with a highly branched network of capillaries and ducts, is crucial for its function. Environmental cues mediate the remodeling process, but the mechanism that underlies this process is largely unknown. OBJECTIVE: Polydom (also called Svep1) is an extracellular matrix protein identified as a high-affinity ligand for integrin α9ß1. However, its physiological function is unclear. Here, we investigated the role of Polydom in lymphatic development. METHODS AND RESULTS: We generated Polydom-deficient mice. Polydom-/- mice showed severe edema and died immediately after birth because of respiratory failure. We found that although a primitive lymphatic plexus was formed, it failed to undergo remodeling in Polydom-/- embryos, including sprouting of new capillaries and formation of collecting lymphatic vessels. Impaired lymphatic development was also observed after knockdown/knockout of polydom in zebrafish. Polydom was deposited around lymphatic vessels, but secreted from surrounding mesenchymal cells. Expression of Foxc2 (forkhead box protein c2), a transcription factor involved in lymphatic remodeling, was decreased in Polydom-/- mice. Polydom bound to the lymphangiogenic factor Ang-2 (angiopoietin-2), which was found to upregulate Foxc2 expression in cultured lymphatic endothelial cells. Expressions of Tie1/Tie2 receptors for angiopoietins were also decreased in Polydom-/- mice. CONCLUSIONS: Polydom affects remodeling of lymphatic vessels in both mouse and zebrafish. Polydom deposited around lymphatic vessels seems to ensure Foxc2 upregulation in lymphatic endothelial cells, possibly via the Ang-2 and Tie1/Tie2 receptor system.

Modification of oligonucleotides with weak basic residues via the 2'-O-carbamoylethyl linker for improving nuclease resistance without loss of duplex stability and antisense activity.

For the improvement of nuclease resistance, four kinds of new modifications through a carbamoylethyl linker were designed. Among them, the 2'-O-[2-N-{2-(benzimidazol-1-yl)ethyl}carbamoylethyl] modification showed 20-fold longer half-life when treated with a 3' to 5' exonuclease compared to the 2'-O-methoxyethyl (MOE) modification, which is used in approved drugs. In addition, this large modification did not disturb the binding affinity or RNase H-dependent antisense activity. From these findings, it could be concluded that an adequate linker, such as carbamoylethyl in this study, could extend the utility of 2'-O-modification without loss of the properties of nucleic acids. This strategy would be useful for the development of nucleic acid therapeutics.

Distal Limited Open Stenting for Aortic Diverticulum in the Right Aortic Arch.

An aortic diverticulum, including Kommerell's diverticulum, is an uncommon, congenital, aortic arch anomaly. Surgery for a diverticulum is challenging, and several surgical strategies have been reported. Here, we present the case of an asymptomatic 57-year-old man who was referred to our hospital. Computed tomography revealed right aortic arch and aortic diverticulum, and he underwent distal limited open stenting under hypothermic circulatory arrest with selective cerebral perfusion via median sternotomy. The postoperative course was uneventful. Thus, this report shows that our procedure is useful and safe for treating aortic diverticulum.