Mycotic pulmonary artery pseudoaneurysm following total arch replacement: a case report

BACKGROUND

Although the true prevalence and incidence are not clearly known, mycotic pulmonary artery aneurysm is a potentially devastating condition that leads to high mortality, over 60% if untreated. Among them, mycotic pulmonary artery pseudoaneurysm, which occurs in relatively central areas, has rarely been reported. We report an extremely rare case of a late complication with a mycotic pulmonary artery pseudoaneurysm, presumably due to infective endocarditis, in a 68-year-old woman 4 months after total arch replacement.

CASE PRESENTATION

A 68-year-old woman was referred to our department for 2 weeks with fever of unknown origin. She had a history of emergency total arch replacement for an acute type A aortic dissection 4 months earlier and chronic rheumatoid arthritis on monthly subcutaneous tocilizumab treatment for several years. Blood culture was positive for Enterococcus faecalis. Transthoracic and transesophageal echocardiography revealed a left ventricular ejection fraction of 58%, severe mitral regurgitation with a 15-mm diameter vegetation on the anterior mitral leaflet, and severe aortic insufficiency with string-like structures. Contrast computed tomography showed a focal saccular outpouching from the right pulmonary artery. On 18F-fluorodeoxyglucose (FDG) positron emission tomography, focal uptake of FDGs was observed along the same lesion of the pulmonary artery and ascending-arch graft. The patient eventually recovered after the surgical intervention of mitral and aortic valve replacement, re-total arch replacement, pulmonary artery repair, application of omental flap, and antibiotics without any evidence of re-infection after 1 year.

CONCLUSIONS

We report a successful surgical repair of mycotic pulmonary artery pseudoaneurysm 4 months after total arch replacement for acute type A aortic dissection. This report describes an effective treatment for an extremely rare postoperative condition.

Overview of acute type A dissection in Japan

Acute type A aortic dissection is a relatively uncommon but devastating disease and usually requires emergency surgery. Based on the several database projects, a large amount of perioperative patient data has now been accumulated and is expected to be useful in clinical practice. Especially in Japan, the number of surgeries for acute type A aortic dissection has been gradually increasing recently, and the overall mortality rate has stabilized at less than 10%. One of the keys to further improvement in outcomes will be to improve the results of aortic root replacement. In addition, strategies need to be established for very elderly patients, comatose patients, and patients with malperfusion as preoperative conditions. The use of a relatively new device, the frozen elephant trunk, is also increasing and might be changing the surgical outcome. In this report, we describe the current status of acute type A aortic dissection in Japan, with reference to recent guidelines and literature.

Acute Type A Aortic Dissection in Adolescents and Young Adults under 30 Years of Age: Demographics, Etiology and Postoperative Outcomes of 139 cases

BACKGROUND

The prevalence and etiology of acute aortic dissection type A in patients ≤30 years is unknown. The aims of this clinical study were to determine the prevalence and potential etiology of acute aortic dissection type A in surgically treated patients ≤30 years and to evaluate the respective postoperative outcomes in this selective group of patients in a large multi-centre study.

METHODS

Retrospective data collection was performed at the 16 participating international aortic institutions. All patients ≤30years at the time of dissection onset were included. The postoperative results were analysed with regard to connective tissue disease.

RESULTS

The overall prevalence of acute aortic dissection type A ≤ 30years was 1.8% (139 out of 7914 patients), including 51(36.7%) patients who were retrospectively diagnosed with connective tissue disease. Cumulative postoperative mortality was 8.6%, 2.2% and 1.4%, respectively. Actuarial survival was 80% at 10 years postoperatively. Non- connective tissue disease patients (n = 88) had a significantly higher incidence of arterial hypertension (46.6%vs.9.8%;p<0.001) while acute aortic dissection type A affected the aortic root (p < 0.001) and arch (p = 0.029) significantly more often in the connective tissue disease group. A positive family history of aortic disease was present in 9.4% of the study cohort(n = 13).

CONCLUSIONS

The prevalence of acute aortic dissection type A in surgically treated patients ≤30 years is less than 2% with connective tissue disease and arterial hypertension as the two most prevalent triggers of acute aortic dissection type A. Open surgery may be performed with good early results and excellent mid- to long-term outcomes.

[Emergency Surgical Management for Stanford Type B Acute Aortic Dissection]

Since a certain number of patients with Stanford type B acute aortic dissection have complications such as rupture and malperfusion (complicated type B), it is important to understand the pathogenesis of this condition and to avoid misjudging the timing and methods of invasive treatment such as thoracic endovascular aortic repair( TEVAR) and graft replacement. TEVAR is widely accepted as a less invasive treatment than conventional surgery, and is usually recognized as the first-line treatment, especially for complicated type B. On the other hand, there is still little clear evidence for TEVAR for uncomplicated type B without rupture or malperfusion, and careful selection of cases is considered necessary. In this review article, we describe the acute treatment of Stanford type B acute aortic dissection with reference to recent guidelines and literature.

Therapeutic potential of clinical-grade human induced pluripotent stem cell-derived cardiac tissues

Objectives

To establish a protocol to prepare and transplant clinical-grade human induced pluripotent stem cell (hiPSC)-derived cardiac tissues (HiCTs) and to evaluate the therapeutic potential in an animal myocardial infarction (MI) model.

Methods

We simultaneously differentiated clinical-grade hiPSCs into cardiovascular cell lineages with or without the administration of canonical Wnt inhibitors, generated 5- layer cell sheets with insertion of gelatin hydrogel microspheres (GHMs) (HiCTs), and transplanted them onto an athymic rat MI model. Cardiac function was evaluated by echocardiography and cardiac magnetic resonance imaging and compared with that in animals with sham and transplantation of 5-layer cell sheets without GHMs. Graft survival, ventricular remodeling, and neovascularization were evaluated histopathologically.

Results

The administration of Wnt inhibitors significantly promoted cardiomyocyte (CM) (P < .0001) and vascular endothelial cell (EC) (P = .006) induction, which resulted in cellular components of 52.0 ± 6.1% CMs and 9.9 ± 3.0% ECs. Functional analyses revealed the significantly lowest left ventricular end-diastolic volume and highest ejection fraction in the HiCT group. Histopathologic evaluation revealed that the HiCT group had a significantly larger median engrafted area (4 weeks, GHM(-) vs HiCT: 0.4 [range, 0.2-0.7] mm² vs 2.2 [range, 1.8-3.1] mm²; P = .005; 12 weeks, 0 [range, 0-0.2] mm² vs 1.9 [range, 0.1-3.2] mm²; P = .026), accompanied by the smallest scar area and highest vascular density at the MI border zone.

Conclusions

Transplantation of HiCTs generated from clinical-grade hiPSCs exhibited a prominent therapeutic potential in a rat MI model and may provide a promising therapeutic strategy in cardiac regenerative medicine.

Updates in aortic wall pathology

Several studies have investigated the pathogenesis of aortic wall abnormalities such as aortic dissection or aneurysm; however, the comprehensive pathological in situ event involved in the development of the disease is not understood well. The vasa vasorum form a network of capillaries or venules around the adventitia and outer media, which play an important role in the aortic wall structure and function. Impairment of their function may induce tissue hypoxia, impede the transfer of cellular nutrients, and cause aortic medial degeneration, which is considered the major predisposing factor to this aortic wall pathology. This review updates our understanding of the pathological changes in the aortic media and vasa vasorum of patients with aortic dissection and aortic aneurysm.

A multi-centre, retrospective case series of oocyte cryopreservation in unmarried women diagnosed with haematological malignancies

STUDY QUESTION

Is oocyte cryopreservation an applicable option for fertility preservation in unmarried patients with haematological malignancies?

SUMMARY ANSWER

Oocyte cryopreservation via the vitrification method is accessible and may be considered an option for fertility preservation in unmarried patients with haematological malignancies.

WHAT IS KNOWN ALREADY

Haematological malignancies are most commonly observed amongst adolescent and young adult women. Although the survival rate and life expectancy of those with haematological malignancies have improved, chemotherapy and radiotherapy may impair their reproductive potential. Oocyte cryopreservation is thus an ideal option to preserve their fertility.

STUDY DESIGN SIZE DURATION

This study retrospectively evaluated 193 unmarried patients (age: 26.2 ± 0.4 years) with haematological malignancies, who consulted for oocyte cryopreservation across 20 different fertility centres in Japan between February 2007 and January 2015. The primary outcome measures were the oocyte retrievals and oocyte cryopreservation outcomes. The secondary outcome measures were the outcomes following oocyte warming for IVF.

PARTICIPANTS/MATERIALS SETTING METHODS

The patients had commenced ovarian stimulation cycles via antagonist, agonist, natural and minimal methods for oocyte retrievals, defined according to the treatment strategy of each respective fertility centre. A vitrification method using the Cryotop safety kit was used for oocyte cryopreservation. ICSIs were used for insemination of warmed oocytes. The endometrial preparation method for embryo transfer was hormonal replacement therapy, except in the case of a patient who underwent a spontaneous ovulatory cycle.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 193 patients, acute myeloid leukaemia (n = 45, 23.3%) was most common, followed by acute lymphoid leukaemia (n = 38, 19.7%) and Hodgkin's lymphoma (n = 30, 15.5%). In total, 162 patients (83.9%) underwent oocyte retrieval, and oocytes were successfully cryopreserved for 155 patients (80.3%). The mean number of oocyte retrieval cycles and cryopreserved oocytes were 1.7 ± 0.2 and 6.3 ± 0.4, respectively. As of December 2019, 14 patients (9.2%) had requested oocyte warming for IVF. The survival rate of oocytes after vitrification-warming was 85.2% (75/88). The rates of fertilisation and embryo development were 80.0% (60/75) and 46.7% (28/60), respectively. Ten patients (71.4%) had successful embryo transfers, and seven live births (50.0%) were achieved.

LIMITATIONS REASONS FOR CAUTION

This study was limited by its retrospective nature. Additionally, there remains an insufficient number of cases regarding the warming of vitrified oocytes to reliably conclude whether oocyte cryopreservation is effective for patients with haematological malignancies. Further long-term follow-up study is required.

WIDER IMPLICATIONS OF THE FINDINGS

Oocyte retrieval and oocyte cryopreservation were accessible for patients with haematological malignancies; however, the number of oocyte retrievals may have been limited due to the initiation of cancer treatments. Acceptable embryonic and pregnancy outcomes could be achieved following oocyte warming; therefore, our results suggest that oocyte cryopreservation can be considered an option for fertility preservation in patients with haematological malignancies.

STUDY FUNDING/COMPETING INTERESTS

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. The authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Novel device prototyping for endoscopic cell sheet transplantation using a three-dimensional printed simulator

Introduction

Considering higher risks of candidates for cardiac regenerative therapy with compromised cardiac function, it is anticipated to develop less invasive surgical procedures. In the present study, we aimed to develop a prototype of totally endoscopic cell sheet delivery device and evaluate the surgical technique for epicardial cell sheet placement using three-dimensional (3D) printed simulators based on human computed tomography data.

Methods

We designed an endoscopic cell sheet delivery device with outer and inner frame with self-expandable applicator which can be opened in thoracic cavity. We launched spout line to provide liquids on the applicator surface and tension line to gently bend the applicator dorsally. We prepared human mesenchymal stem cell (MSC) sheets and compared wet/dry conditions of 3D printed heart/porcine heart and applicator to identify suitable conditions for cell sheet transplantation. Finally we validated the feasibility of endoscopic transplantation to anterior and lateral wall of left ventricle using 3D printed simulators.

Results

Moist condition of both 3D printed heart/porcine heart surface and applicator at transplantation yielded highest successful rate (100%, p = 0.0197). For both endoscopic transplantation sites, MSC sheets were successfully deployed. The procedure duration was 157 ± 23 s for anterior wall and 123 ± 13 s for the lateral wall in average, respectively.

Conclusions

We developed a novel prototype of endoscopic cell sheet delivery device for minimally-invasive cardiac regenerative therapy utilizing a 3D printed simulator. The commercialization of the prototype may provide a safe minimally-invasive method to deliver potential cardiac regenerative therapy in the future.

•

We invented a novel device for endoscopic cell sheet transplantation.

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We optimized the transplantation procedure using three-dimensional printed simulator.

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Commercialization of the device may provide standardized cardiac regenerative therapy.

Transplantation of clinical-grade human induced pluripotent stem cell derived cardiac tissues contributes to functional recovery in a rat myocardial infarction model

Background

Clinical-grade human induced pluripotent stem cells (iPSCs) established from a healthy volunteer are currently being considered as a quality controlled cell source for regenerative therapy. Transplantation of three-dimensional bioengineered cardiac tissues composed of human iPSC-derived cardiovascular cell lineages is reported to hold potential for cardiac functional recovery.

Purpose

The aims of this study were to evaluate tissue conformation and cellular viability of human iPSC-derived cardiac tissues (HiCTs) generated from clinical-grade cells and to validate functional efficacy of HiCT transplantation.

Methods

Clinical-grade human iPSC lines were simultaneously differentiated into cardiovascular cell lineages by a high-density monolayer culture. The differentiation efficacy was analyzed by flow cytometry. We seeded the cells on temperature responsive culture dishes to form cell sheets. HiCTs are generated by stacking 5 cell sheets with insertion of gelatin hydrogel microspheres (GHMs) between each sheet to promote oxygen and nutrition supply. Characteristics of the HiCTs are histologically and immunohistochemically evaluated. The HiCTs were transplanted onto an athymic nude rat myocardial infarction (MI) model. Cardiac function was evaluated by echocardiography and cardiac magnetic resonance imaging (MRI) until 4 weeks after surgery, and compared to those in animals with sham operation and with cell sheet stacks without GHMs [GHM(−)].

Results

Flow cytometry at differentiation day15 revealed cellular components as follows: 52.5±1.4% of cardiomyocytes (cardiac isoform of troponin-T+), 9.8±0.7% of vascular endothelial cells (VE-cadherin+), 14.8±1.8% of vascular mural cells (PDGFRβ+) and 0.2±0.1% of undifferentiated cells (TRA-1-60+). HiCTs were significantly thicker [GHM(−) vs HiCT: 357.3±81.5 vs 723.0±84.0μm, p&lt;0.05], composed of higher area of cardiomyocytes (27.7±7.9 vs 71.9±15.5mm2, p&lt;0.05) and endothelial cells (CD31+) (1.6±0.7 vs 9.2±1.5mm2, p&lt;0.05), free from hypoxia (HIF-1α+) (3.1±0.1 vs 0.8±0.2%, p&lt;0.05) and cell death (TUNEL+) (3.2±0.1 vs 1.4±0.3%, p&lt;0.05) after 7 days of in vitro culture. Echocardiography revealed significantly lower left ventricular end diastolic volume (LVEDV) and higher left ventricular ejection fraction (LVEF) in HiCT group [sham (n=27) vs GHM(−) (n=12) vs HiCT (n=12): LVEDV; 1.4±0.1 vs 1.3±0.1 vs 0.9±0.1mL, p&lt;0.0001/LVEF; 55.3±1.1 vs 58.2±2.3 vs 78.2±1.5%, p&lt;0.0001]. Cardiac MRI showed lower LVEDV and higher LVEF as well [sham (n=8) vs GHM(−) (n=6) vs HiCT (n=6): LVEDV; 0.7±0.03 vs 0.7±0.03 vs 0.6±0.02mL, p&lt;0.01 / LVEF; 39.2±2.1 vs 43.8±1.4 vs 54.0±2.8%, p&lt;0.001].

Conclusions

We conclude that HiCTs generated from clinical-grade cells hold sufficient viability and tissue conformation suitable for functional recovery validated by a rat MI model. Clinical-grade human iPSCs potentially serve as a reasonable cell source for stem cell-derived product transplantation therapy with foreseeable clinical applications.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Japan Agency for Medical Research and Development (AMED), Invited Research Project of Institute for Advancement of Clinical Transnational Science, Kyoto University Hospital

Accuracy of spiked cell counting methods for designing a pre-clinical tumorigenicity study model

Background

Evaluations for the tumorigenicity of transplantation of stem cell products is mandatory for clinical application. It is of importance to establish a system to accurately quantify contaminated tumorigenic cells regardless of the format of stem cell product. In the present report, we aimed to examine the accuracy of the quantification of tumorigenic cell numbers with commonly used 2 methods, quantitative polymerase chain reaction (qPCR) and flow cytometry (FCM) using experimental models of stem cell products spiked with tumorigenic cells.

Methods

Human mesenchymal stem cells (hMSCs) and melanoma Mewo-Luc cells constitutively expressing luciferase were used. We stained Mewo-Luc cells with a cell linker then spiked onto hMSC suspensions and hMSC sheets. We validated the accuracy of 10-fold serial dilution technique for Mewo-Luc cell suspension using a Coulter counter. The samples spiked with Mewo-Luc cells were subjected to qPCR and FCM analyses, respectively for the quantification of Mewo-Luc cells.

Results

Ten-fold serial dilutions of Mewo-Luc cells were performed accurately with small deviation. In samples spiked with or less than 100 cells in hMSC suspensions, and samples spiked with or less than 1,000 cells in hMSC sheets showed significantly higher cell numbers in calculations by FCM, respectively (suspensions; qPCR vs FCM: 100 cells: 59 ± 25 vs 232 ± 35 cells, p = 0.022/10 cells: 21 ± 7 vs 114 ± 27 cells, p = 0.030, sheets; qPCR vs FCM: 1,000 cells: 1723 ± 258 vs 5810 ± 878 cells, p = 0.012/100 cells: 110 ± 18 vs 973 ± 232 cells, p = 0.012/10 cells: 20 ± 6 vs 141 ± 36 cells, p = 0.030).

Conclusion

Differences in accuracy between quantification methods should be considered in designing a tumorigenicity study model.

Histopathological evaluation of aortic dissection: a comparison of congenital versus acquired aortic wall weakness

OBJECTIVES

The aim of this study was to identify pathological changes of aortic dissection based on histopathological evaluation of aortic wall weakness by comparing patients with and without congenital abnormalities.

METHODS

We reviewed records of patients who underwent repair for dissection-related aortic disease between 2008 and 2015. Fifty patients (20 men and 30 women; mean age 66.9 ± 14.0 years) who underwent surgery with subsequent histopathological examination of the aortic wall were divided into 2 groups. Group 1 had congenital abnormalities, including Marfan syndrome and bicuspid aortic valve (n = 5), and Group 2 had no congenital abnormalities (n = 45). We compared the histopathological characteristics of the aortic wall in these patients.

RESULTS

There were significant differences in age and body surface area between the 2 groups. Although 80% of Group 1 patients developed dissection at the middle of the media, all Group 2 patients developed dissection at the outer one-third of the media, which is along the pathway of the vasa vasorum of the aortic wall. Both groups showed the same extent of degeneration of the vasa vasorum. Group 1 showed a severe score of mucoid extracellular matrix accumulation in the aortic media.

CONCLUSIONS

Although it may be multifactorial, congenital maldevelopment of the media tends to result in dissection of the centre of the media, and acquired aortic wall weakness is concentrated in the outer third of the media. Degeneration of the vasa vasorum may be an important emerging substrate for developing aortic dissection.

[Successful Echo-guided Deployment of Stent Graft for Intraoperative Retrograde Aortic Dissection and Rupture;Report of a Case]

We report a case of chronic dissecting thoracoabdominal aneurysm with intraoperative retrograde aortic dissection and rupture at proximal descending aorta, which was successfully treated by echoguided stent-graft insertion. An 82-year old male underwent thoracoabdominal aortic replacement for dilatation of infra-diaphragmatic aorta. Under F-F bypass, his thoracoabdominal aorta was replaced by a Dacron graft with 4-branches. After he weaned from F-F bypass, we found massive bleeding from proximal descending aorta. Trans-esophageal echocardiography (TEE) showed aortic dissection from the clamp site to the distal anastomotic site of the former total arch replacement. We temporary got hemostasis by suture and surgical glue, and anastomosed a 10 mm-graft to the thoracoabdominal main graft as conduit, then inserted and deployed 2 pieces of stent-graft. Direct echo and TEE contributed to the accurate positioning of them. Bleeding was completely controlled. He well recovered without paraplegia. Post-operative computed tomography (CT) showed good positioning and dilatation of the stentgraft and the perfect reverse remodeling of thoracic aorta.

A case of feline gastrointestinal eosinophilic sclerosing fibroplasia limited to the mesentery

An entire, female, mixed‐breed cat of unknown age was presented with a 6‐week history of lethargy, anorexia and vomiting. There was an increase in the number of white blood cells in the blood, including neutrophils and eosinophils; moderate anaemia; ascites; and possible mesenteric peritonitis. Exploratory laparotomy revealed firm, multifocal small nodules in the mesentery. As the nodules were surgically unresectable, they were biopsied. Histologically, the nodules were composed of thin trabeculae of dense collagen fibres mixed with plump fibroblasts and numerous eosinophils, consistent with feline gastrointestinal eosinophilic sclerosing fibroplasia. Bacteria were not detected on histological examination of the nodules and cytology of the ascites. Remission of disease occurred following treatment with prednisolone and ciclosporin A for 22 days and antibiotics for 40 days. After remission, ciclosporin A was administered for 236 days and then discontinued. Eosinophilia also resolved after treatment with ciclosporin A. The cat is still alive and in good condition on day 689. This report describes what may be an atypical case of feline gastrointestinal eosinophilic sclerosing fibroplasia, lacking involvement of the gastrointestinal tract, and was apparently cured by treatment that involved ciclosporin A.

Intimal Flap Vegetation Following Aortic Root Re-dissection

A 75-year-old man who had undergone ascending aorta replacement for acute Type A aortic dissection presented with a recurring high fever. Transesophageal echocardiography revealed that a vegetation had formed on the re-dissected intimal flap of the noncoronary sinus of Valsalva. This didactic case suggests that antibiotic prophylactic measures be considered for aortic dissection flaps as for irregular valves susceptible to infective endocarditis.

Coronary artery bypass graft in a patient with Fabry's disease

Fabry's disease is a lysosomal storage disease characterized by intracellular accumulation of ceramide trihexoside resulting from alpha-galactosidase A deficiency. While the heart is often involved, coronary artery disease and its management in Fabry's disease patients are extremely rare clinical entities. We report a case of a 72-year-old man with left main disease in Fabry's disease with special consideration of the arterial wall pathology.

[Severe Perioperative Coronary Artery Spasm in Thoracic Aortic Surgery; Report of Two Cases]

We report 2 cases of severe perioperative coronary artery spasm in thoracic aortic surgery. Case 1 was a 72-year-old male with a distal arch aneurysm of 74 mm while case 2 was a 74-year-old male with acute type A aortic dissection. We performed thoracic aortic repair (total arch replacement and ascending aorta replacement) under moderately hypothermic circulatory arrest (25 °C) and selective cerebral perfusion in both cases. ST elevation, abnormal left ventricular wall motion, and hypotension were noted intraoperatively. Because we were not able to wean the patients from the cardiopulmonary bypass, intraaortic balloon pump was initiated in case 1 and a coronary artery bypass graft was added in case 2. In addition to using vasodilators such as diltiazem, case 1 recovered without further intervention, but case 2 developed cardiopulmonary arrest and needed resuscitation on postoperative day 5 because of recurrence of coronary spasm. Perioperative coronary artery spasm is rare especially in aortic surgery, and may become lethal. Early recognition and special hemodynamic support is required.

Giant atrial septal aneurysm originating from the right coronary artery

Giant coronary artery aneurysm is a rare clinical entity and its involvement in the interatrial space is extremely rare. We here report the rare surgical case of a 67-year old man with giant right coronary artery aneurysm located in the atrial septum with fistula formation to the right atrium, complicated with congestive heart failure, rapid atrial fibrillation and left atrial appendage thrombus. The patient eventually recovered fully without sequelae.

Chemical fragment arrays for rapid druggability assessment

Incorporation of early druggability assessment in the drug discovery process provides a means to prioritize target proteins for high-throughput screening.

Abstract 672: Histopathological Comparison of Ascending Aortic Aneurysm: Bicuspid versus Tricuspid Aortic Valve Patients

Introduction: The pathogenic mechanisms of ascending aortic aneurysm are not fully understood. The aim of this study was to identify the beginning of aortic wall dilatation based on histopathological evaluation by comparison of patients with bicuspid versus tricuspid aortic valves.

Methods: Twenty-one patients (9 males, 12 females; mean age, 69±8.9 years) who underwent ascending aortic repair from 2008 to 2014 were divided into bicuspid aortic valve (n=8, Group B) and tricuspid aortic valve (n=13, Group T) subgroups. We compared the histopathological characteristics of the ascending aortic wall in these patients.

Results: There were no significant differences between the two groups in age, sex, history of hypertension, and maximum diameter of the ascending aorta (Group B: 51.4±5.1 mm; Group T: 55.5±8.8 mm; p=0.247) at the time of operation. While all Group B cases exhibited aortic stenosis, there was only one case in Group T. Sclerosis or hypertrophy of the vasa vasorum was evident in both groups (Group B: 7 patients, 87.5%; Group T: 10 patients, 76.9%; p=1.000). Group B patients exhibited a much thinner aortic wall, resulting from frail smooth muscle cells of media, which induced a fragile thinner elastic lamina. The histopathological pattern of Group T was variable and included atheroma, inflammatory granulation tissue and a Marfan-like acid mucopolysaccharide pool, which produce severe fragmentation of elastic lamina.

Conclusions: Degeneration of the vasa vasorum, which induces chronic ischemia or malnutrition of the aortic wall, is an important emerging substrate for the development of ascending aortic aneurysm. Bicuspid aortic valve patients exhibited congenital maldevelopment of the medial smooth muscle cells and elastic lamina. Tricuspid aortic valve patients exhibited severe fragmentation of elastic lamina, which induced by pathological changes including atheroma, inflammatory granuloma, and a Marfan-like acid mucopolysaccharide pool.

Acute coronary artery bypass graft failure in a patient with polycythemia vera

Polycythemia vera in patients undergoing cardiac surgery is clinically rare. A 65-year-old man with polycythemia vera was admitted with effort-related chest discomfort. We planned coronary artery bypass grafting for left anterior descending artery and obtuse marginal branch stenosis, using bilateral internal thoracic arteries, with perioperative prophylactic management to avoid thromboembolism. His internal thoracic arterial grafts occluded during and after surgery due to thrombus, and ST-elevation myocardial infarction developed, which needed a percutaneous coronary intervention. This case suggests that optimal management methods should be studied further to contribute to better patient outcomes in this condition.

Right atrial volume reduction for severely impaired pulmonary function

We report a patient with giant right atrium and severe pulmonary dysfunction who underwent successful surgical volume reduction with significant improvement of pulmonary function studies.

Effects of acivicin on growth, mycotoxin production and virulence of phytopathogenic fungi

Acivicin is an inhibitor of γ-glutamyl transpeptidase and glutamine amidotransferase. When grown on a synthetic minimal agar medium, acivicin strongly inhibited the growth of Magnaporthe oryzae and Alternaria brassicicola, and to a lesser extent, Botrytis cinerea. However, only partial or marginal growth inhibition was observed with regard to Fusarium sporotrichioides and Fusarium graminearum. The growth retardation caused by acivicin was significantly alleviated by cultivating the fungus on a nutrient-rich medium. The inhibition of M. oryzae growth caused by 1 μmol l(-1) of acivicin on minimal agar medium was subdued by the addition of specific single amino acids, including His, a branched-chain amino acid (Leu, Ile or Val), an aromatic amino acid (Trp, Tyr or Phe), Met or Gln, at a concentration of 0·4 mmol l(-1). Trichothecene production by F. graminearum in trichothecene-inducing liquid medium was reduced significantly in the presence of acivicin despite its inability to inhibit growth in the trichothecene-inducing liquid medium. Foliar application of conidia in the presence of acivicin reduced the severity of rice blast disease caused by M. oryzae. These results suggest the usefulness of this modified amino acid natural product to mitigate agricultural problems caused by some phytopathogenic fungi. Significance and impact of the study: Fusarium head blight or scab disease and rice blast, caused by Fusarium graminearum and Magnaporthe oryzae, respectively, are major diseases of cereal crops that cause a significant loss of yield and deterioration in the quality of the grain. The present study investigated the effects of acivicin, a glutamine amino acid analog, on the physiology of various phytopathogenic fungi. Application of acivicin to a fungal culture and conidial suspension reduced mycotoxin production by the wheat scab fungus and the severity of rice blast, respectively. These results suggest the possibility that acivicin may serve as a lead compound to develop agricultural chemicals for the control of some plant diseases.

Acute subdural hematoma after aortic surgery: a retrospective comparative study

BACKGROUND

Acute subdural hematoma is uncommon following open-heart surgery, but may result in increased mortality and morbidity.

METHODS

A retrospective analysis was performed involving all patients who underwent thoracic aortic surgery from January 2009 to February 2013. There were 53 patients who had thoracic aortic repair with open distal anastomosis and required selective cerebral perfusion with or without retrograde cerebral perfusion. We evaluated the incidence of postoperative acute subdural hematoma. The patients were divided into two groups: a subdural hematoma group who had symptomatic subdural hematoma postoperatively, and a non-subdural hematoma group who had no subdural hematoma. The variables were compared between the 2 groups.

RESULTS

Eight (15.1%) patients had a transient symptomatic subdural hematoma; none required surgical evacuation of the hematoma. There were significant differences between the two groups in terms mean and maximum retrograde cerebral perfusion flow, and the volume of intraoperative platelet transfusion. Multivariate analysis revealed that a significant risk factor for acute subdural hematoma following thoracic aortic surgery was the amount of intraoperative platelet transfusion (odds ratio = 0.9, 95% confidence interval: 0.81-0.98, p = 0.015).

CONCLUSIONS

This retrospective study demonstrated that the subdural hematoma group received fewer units of platelets, thus it appears to be important to give platelets appropriately. Strict flow regulation or avoidance of retrograde cerebral perfusion is suggested.

Partial aortic root replacement for aneurysm of the right sinus of Valsalva

An aneurysm of the sinus of Valsalva is clinically rare, and its operative indications and procedures are controversial. We herein report the rare case of a 68-year-old woman with severe right ventricular outflow tract obstruction caused by an aneurysm of the right sinus of Valsalva. We performed partial aortic root reconstruction using a bovine pericardial patch, and aortic valve replacement. Although this case provides evidence that these are suitable surgical techniques for treatment of aneurysm of the sinus of Valsalva, total aortic root replacement should have been chosen based on the pathological finding of aortic medial and valve degeneration.

A small compound targeting TACC3 revealed its different spatiotemporal contributions for spindle assembly in cancer cells

The mitotic spindle is assembled by the coordinated action of centrosomes and kinetochore microtubules. An evolutionally conserved protein family, transforming acidic coiled-coil (TACC), has been shown to be involved in this process. In humans, TACC3 is aberrantly expressed in a variety of human cancers, but its biological significance remains to be elucidated. Here, using a novel compound targeting TACC3, spindlactone (SPL), we show that the perturbation of TACC3 selectively inhibited the nucleation of centrosome microtubules in ovarian cancer cells. In contrast to centrosome microtubules, the kinetochore microtubules were robustly assembled, forming ectopic spindle poles that resulted in multipolar spindles. Interestingly, the extensive inhibition of TACC3 partially suppressed the nucleation of kinetochore microtubules. These dose-dependent effects of SPL were consistent with the results observed by the depletion of TACC3 and its binding partner, colonic and hepatic tumor overexpressed gene protein (TOGp). Although these proteins both have roles in the assembly of centrosome and kinetochore microtubules, their contributions were spatiotemporally different. Notably, SPL did not affect spindle assembly in normal cells. Furthermore, the oral administration of SPL significantly suppressed tumor growth in vivo. The unique mechanism of action of SPL not only enables it to be used as a tool to dissect the molecular basis of spindle assembly but also to provide a rationale for the use of TACC3 as a molecular target for cancer treatment. This rationale offers an opportunity to develop new strategies for cancer chemotherapy that overcome the limitations of microtubule toxins and expand their scope and clinical efficacy.

Aortic dissection in the outer third of the media: what is the role of the vasa vasorum in the triggering process?

OBJECTIVES

Extensive clinicopathological analyses of aortic dissection have implicated hypertension and genetic abnormalities as the major pathogenic mechanisms. However, previous findings from pathological examinations have often been inconsistent with these mechanisms. In this paper, we suggest a significant role for the vasa vasorum in the aetiology and pathogenesis of aortic dissection.

METHODS

We reviewed records of patients who underwent thoracic aortic dissection repair at our institution between June 2008 and August 2011. Twenty-one patients (10 men, 11 women; mean age, 65.0 ± 12.0 years) underwent surgery with subsequent histopathological examination of the aortic wall. We evaluated the history and histopathological findings of these patients.

RESULTS

Aortic medial changes were observed in all 21 patients. These changes included thinning and sometimes fragmentation of the elastic lamina, as well as atrophy of the smooth muscle cells, with surrounding accumulation of an Alcian blue-positive mucinous substance, mostly adjacent to the dissection. Importantly, the dissection was located in the outer third of the media in 20 of the 21 patients (95.2%). Of these 20, 18 showed histopathological evidence of sclerotic changes of the vasa vasorum, including muscular hyperplasia, elastosis, intimal fibrosis and/or luminal obstruction, and even rupture. These changes may have been secondary to hypertension or peri-aortic changes, leading to degenerative changes in the aortic media and even initiation of dissection.

CONCLUSIONS

Most aortic dissections initially developed in the outer third of the media alongside the vasa vasorum. In this type of aortic dissection, dysfunction of the vasa vasorum may play a key role in long-standing ischaemia or malnutrition of the aortic media.