Annuloplasty ring removal from patients with hemolysis after mitral valve repair.

We present a case of severe hemolysis following a mitral valve repair, which was successfully treated by removing the annuloplasty ring. The etiology of the hemolysis appeared to be a small regurgitant jet at the level of the annuloplasty ring.

Zinc and its transporter ZIP6 are key mediators of breast cancer cell survival under high glucose conditions.

Recent studies have shown that hyperglycaemia is related to breast cancer progression; however, the mechanisms underlying the relationship between hyperglycaemia and breast cancer cell survival remain unknown. Here, we demonstrate that as compared to physiological glucose conditions, high glucose conditions promote a significant increase in MCF-7 cell survival under hypoxia. High glucose levels inhibit apoptosis and induce epithelial-to-mesenchymal transition, resulting in increased cell viability under hypoxic conditions. Moreover, high glucose-treated cells display significant increases in intracellular Zn2+ levels and reduction in mRNA expression of the zinc (Zn) transporter Zrt- and Irt-like protein 6 (ZIP6) in hypoxia. ZIP6 deficiency disturbs intracellular Zn2+ homeostasis, leading to increased cell survival in hypoxia and reduced E-cadherin expression, indicating that decreased ZIP6 expression is strongly associated with resistance to hypoxia.

HpDTC1, a Stress-Inducible Bifunctional Diterpene Cyclase Involved in Momilactone Biosynthesis, Functions in Chemical Defence in the Moss Hypnum plumaeforme.

Momilactones, which are diterpenoid phytoalexins with antimicrobial and allelopathic functions, have been found only in rice and the moss Hypnum plumaeforme. Although these two evolutionarily distinct plant species are thought to produce momilactones as a chemical defence, the momilactone biosynthetic pathway in H. plumaeforme has been unclear. Here, we identified a gene encoding syn-pimara-7,15-diene synthase (HpDTC1) responsible for the first step of momilactone biosynthesis in the moss. HpDTC1 is a bifunctional diterpene cyclase that catalyses a two-step cyclization reaction of geranylgeranyl diphosphate to syn-pimara-7,15-diene. HpDTC1 transcription was up-regulated in response to abiotic and biotic stress treatments. HpDTC1 promoter-GUS analysis in transgenic Physcomitrella patens showed similar transcriptional responses as H. plumaeforme to the stresses, suggesting that a common response system to stress exists in mosses. Jasmonic acid (JA), a potent signalling molecule for inducing plant defences, could not activate HpDTC1 expression. In contrast, 12-oxo-phytodienoic acid, an oxylipin precursor of JA in vascular plants, enhanced HpDTC1 expression and momilactone accumulation, implying that as-yet-unknown oxylipins could regulate momilactone biosynthesis in H. plumaeforme. These results demonstrate the existence of an evolutionarily conserved chemical defence system utilizing momilactones and suggest the molecular basis of the regulation for inductive production of momilactones in H. plumaeforme.

Resuspension of the uninfarcted papillary muscle at the time of mitral valve replacement in a patient with post myocardial infarction papillary muscle rupture.

A 60-year-old woman was referred to the Department of Cardiovascular Surgery of Social Insurance Chukyo Hospital for the rupture of a postinfarction papillary muscle. The rupture was in the posterior part of the anterolateral papillary muscle, in which more than two-thirds of its posterior leaflet was prolapsed. Mortality from the surgical repair of a papillary muscle rupture is quite high. For this case, we resuspended the uninfarcted papillary muscle heads case to preserve mitral ventricular continuity because the mitral annulus was quite small and more than two-thirds of the posterior leaflet were detached from the papillary muscle. The post-operative course of the patient was uneventful. Resuspension of uninfarcted papillary muscle is a useful technique to repair a rupture in the papillary muscle.

Retrograde coronary sinus cardioplegia cannula placement under short-time circulatory arrest in surgery for a ruptured type A dissection with a previous coronary artery bypass.

A 79-year-old woman was referred to undergo surgery for a type A dissection. The patient had a history of previous coronary artery bypass. She was in shock and had a hematoma surrounding the ascending aorta and the heart. In this case, a coronary sinus cardioplegia cannula was placed under a short period of circulatory arrest via a small atriotomy, and the atriotomy was closed immediately to establish selective cerebral perfusion.

The case of an explanted 16-year-old mitral Carpentier-Edwards pericardial bioprosthesis.

We report the case of a mitral Carpentier-Edwards pericardial bioprosthesis that was explanted from a 43-year-old female patient because of structural valve deterioration 16 years following implantation. Upon removal, the prosthesis was found to be discolored and all leaflets were stiff and hard, showing extensive calcification, pannus overgrowth, leaflet hematoma, and multiple disruptions. One leaflet presented a wavy free margin due to commissural disruptions, leading to incomplete cusp coaptation. The accumulated physical symptoms of the patient were consistent with these findings.