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Aorto-ventricular tunnel (AoVT), a rare congenital anomaly, is a channel originating in the ascending aorta just above the sinotubular junction and leading to the cavity of the left ventricle (AoLVT), or, rarely, the right (AoRVT). This study reviews our collective 30-year experience with the surgical treatment of AoVT. Data were submitted by 15 participating centers on 42 patients who underwent correction of AoVT between 1987 and 2018. Of these, 36 had AoLVT, and 6 AoRVT. The tunnel originated above the right coronary sinus in 28 (77.8%) patients. For AoLVT, most operations were performed early (median age 25 days, range: 1 day–25 years). In contrast, AoRVT was diagnosed and repaired later (median age 6 years, range: 1 month–12 years). Surgically important coronary ostial displacement was common. Patch closure of the aortic orifice only was the commonest surgical repair for AoLVT (23 patients), while in AoRVT, both orifices or only the ventricular one was closed. Aortic valvar insufficiency, severe or moderate, coexisted in 11 (30.5%) patients with AoLVT, and aortic valvuloplasty was performed in 8, mainly due to aortic valve stenosis. Aortic valvar insufficiency at discharge ranged from trivial to mild in almost all patients. Early mortality was 7.14%, with 3 patients with AoLVT succumbing to cardiac failure. There were 2 early reoperations and 1 late death. AoVT is a rare malformation. AoLVT usually necessitates surgery in early life. AoRVT is rarer, diagnosed and repaired later in life. Surgical repair by patch closure, with concomitant aortic valve repair as needed, is associated with good results.

Labeling experiments in chicken and mouse embryos have revealed important roles for different cell lineages in the development of the cardiac arterial pole. These data can only fully be exploited when integrated into the continuously changing morphological context and compared with the patterns of gene expression. As yet, studies on the formation of separate ventricular outlets and arterial trunks in the human heart are exclusively based on histologically stained sections. So as to expand these studies, we performed immunohistochemical analyses of serially sectioned human embryos, along with three-dimensional reconstructions. The development of the cardiac arterial pole involves several parallel and independent processes of formation and fusion of outflow tract cushions, remodeling of the aortic sac and closure of an initial aortopulmonary foramen through formation of a transient aortopulmonary septum. Expression patterns of the transcription factors ISL1, SOX9 and AP2alpha show that, in addition to fusion of the SOX9-positive endocardial cushions, intrapericardial protrusion of pharyngeal mesenchyme derived from the neural crest contributes to the separation of the developing ascending aorta from the pulmonary trunk. The non-adjacent walls of the intrapericardial arterial trunks are formed through addition of ISL1-positive cells to the distal outflow tract, while the facing parts of the walls form from the protruding mesenchyme. The morphogenetic steps, along with the gene expression patterns reported in this study, are comparable to those observed in the mouse. They confirm the involvement of mesenchymal tissues derived from endocardium, mesoderm and migrating neural crest cells in the process of initial septation of the distal part of the outflow tract, and its subsequent separation into discrete intrapericardial arterial trunks.

BACKGROUND: Associations between traffic pollution on the street of residence and a range of respiratory and allergic outcomes in children have been reported in developed countries, but little is known about such associations in developing countries. METHODS: The third phase of the International Study of Asthma and Allergies in Childhood (ISAAC) was carried out in 13- to 14-year-old and 6- to 7-year-old children across the world. A question about frequency of truck traffic on the street of residence was included in an additional questionnaire. We investigated the association between self-reported truck traffic on the street of residence and symptoms of asthma, rhinoconjunctivitis, and eczema with logistic regression. Adjustments were made for sex, region of the world, language, gross national income, and 10 other subject-specific covariates. RESULTS: Frequency of truck traffic on the street of residence was positively associated with the prevalence of symptoms of asthma, rhinoconjunctivitis, and eczema with an exposure–response relationship. Odds ratios (95% confidence intervals) for "current wheeze" and "almost the whole day" versus "never" truck traffic were 1.35 (1.23–1.49) for 13- to 14-year-olds and 1.35 (1.22–1.48) for 6- to 7-year-olds. CONCLUSIONS: Higher exposure to self-reported truck traffic on the street of residence is associated with increased reports of symptoms of asthma, rhinitis, and eczema in many locations in the world. These findings require further investigation in view of increasing exposure of the world's children to traffic.

Septation and separation within the outflow tract of the developing heart. Webb S, Qayyum SR, Anderson RH, Lamers WH, Richardson MK. Department of Anatomy and Developmental Biology, St George's Hospital Medical School, Cranmer Terrace, London SW17 ORE, UK. s.webb@sghms.ac.uk The developmental anatomy of the ventricular outlets and intrapericardial arterial trunks is a source of considerable confusion. First, major problems exist because of the multiple names and definitions used to describe this region of the heart as it develops. Second, there is no agreement on the boundaries of the described components, nor on the number of ridges or cushions to be found dividing the outflow tract, and the pattern of their fusion. Evidence is also lacking concerning the role of the fused cushions relative to that of the so-called aortopulmonary septum in separating the intrapericardial components of the great arterial trunks. In this review, we discuss the existing problems, as we see them, in the context of developmental and postnatal morphology. We concentrate, in particular, on the changes in the nature of the wall of the outflow tract, which is initially myocardial throughout its length. Key features that, thus far, do not seem to have received appropriate attention are the origin, and mode of separation, of the intrapericardial portions of the arterial trunks, and the formation of the walls of the aortic and pulmonary valvar sinuses. Also as yet undetermined is the formation of the free-standing muscular subpulmonary infundibulum, the mechanism of its separation from the aortic valvar sinuses, and its differentiation, if any, from the muscular ventricular outlet septum

Thin ³He-⁴He physisorbed films are examples of strongly interacting, quasi two-dimensional, fermion-boson mixture systems. The properties of the mixture systems can be tuned by changing the substrate or the ⁴He film thickness. In this paper, we discuss the ground-state and magnetic groundstate of the ³He subsystem and also the interactions between the excitations of the ⁴He superfluid film with the single-particle excitations of the adsorbed ³He. The ground-state of the ³He system is calculated using a model for the ³He-³He effective interaction in the static ⁴He film which explicitly includes the effective interaction due to exchange of virtual film excitations (ripplons). This latter effective interaction is evaluated in the random phase approximation and is shown not to be capable of causing the ³He system to be self-bound. We discuss the evidence from magnetization, third sound and heat capacity measurements that the ³He first transverse excited state is being occupied prior to monolayer completion Тонкі плівки ³He-⁴He є прикладом сильно взаємодіючих, квазідвовимірних, ферміонно-бозонних змішаних систем. Властивості змішаних систем можуть бути керовані зміною підкладки або товщини плівки ⁴He. У цій статті ми обговорюємо основний стан і магнітний основний стан підсистеми ³He, а також взаємодії між збудженнями надплинної плівки ⁴He з одночастинковими збудженнями адсорбованого ³He. Основний стан системи ³He обчислюємо, використовуючи модель для ефективної взаємодії ³He-³He у статичній плівці ⁴He, яка явно включає ефективну взаємодію, зумовлену обміном віртуальними плівковими збудженями (ріпплонами). Ця остання ефективна взаємодія оцінюється в наближенні хаотичних фаз, і показано, що вона не є здатна спричиняти самозв’язаність системи ³He. З вимірювань намагніченості, третього звуку і питомої теплоємності ми обговорюємо свідчення того, що перший поперечний збуджений стан ³He заповнюється раніше від завершення моношару.