Tricuspid annulus: A spatial and temporal analysis.

Background: Traditional two‑dimensional (2D) echocardiographic evaluation of tricuspid annulus (TA) dilation is based on single‑frame measurements of the septolateral (S‑L) dimension. This may not represent either the axis or the extent of dynamism through the entire cardiac cycle. In this study, we used real‑time 3D transesophageal echocardiography (TEE) to analyze geometric changes in multiple axes of the TA throughout the cardiac cycle in patients without right ventricular abnormalities. Materials and Methods: R‑wave‑gated 3D TEE images of the TA were acquired in 39 patients undergoing cardiovascular surgery. The patients with abnormal right ventricular/tricuspid structure or function were excluded from the study. For each patient, eight points along the TA were traced in the 3D dataset and used to reconstruct the TA at four stages of the cardiac cycle (end‑ and mid‑systole, end‑ and mid‑diastole). Statistical analyses were applied to determine whether TA area, perimeter, axes, and planarity changed significantly over each stage of the cardiac cycle. Results: TA area (P = 0.012) and perimeter (P = 0.024) both changed significantly over the cardiac cycle. Of all the axes, only the posterolateral‑anteroseptal demonstrated significant dynamism (P < 0.001). There was also a significant displacement in the vertical axis between the points and the regression plane in end‑systole (P < 0.001), mid‑diastole (P = 0.014), and mid‑systole (P < 0.001). Conclusions: The TA demonstrates selective dynamism over the cardiac cycle, and its axis of maximal dynamism is different from the axis (S‑L) that is routinely measured with 2D TEE.

Effectiveness of diode laser trans-scleral cyclophotocoagulation in patients following silicone oil-induced ocular hypertension in Chinese eyes.

We evaluated the effectiveness of diode laser trans-scleral cyclophotocoagulation (TSCPC) on intraocular pressure (IOP) in nine patients having raised IOP following use of silicone oil (SO) for retinal detachment (RD) surgery in a retrospective observational case series. Diode laser TSCPC was applied at a power setting of 1.75 to 2.5 watts, for two sec with a maximum of 30 applications. The patients were followed up for 40 to 312 weeks. The mean pre-laser IOP was 32.06 mm Hg (SD 7.32). The mean post-laser IOP at one month, three months and six months was 17.89 mm Hg (SD 8.23), 21.89 mm Hg (SD 8.16) and 21.67 mm Hg (SD 7.55) respectively. The final IOP (at the last follow-up) was 19.56 mm Hg (SD 7.85) (P=0.021). Seven of them had undergone SO removal. In our observation, effectiveness of TSCPC in long-term control of SO-induced ocular hypertension was limited as compared to short-term control of IOP.

The role of plasminogen activator receptor in cancer invasion and dormancy

Urokinase plasminogen activator receptor (uPAR) has been identified some 15 years ago and the anticipation was that is presence on the cell surface will provide a focus for anchoring uPA and possibly protect the enzyme from native inhibitors. The studies of the last decade have shown that uPA localized to the surface of cells by uPAR is indeed an important factor in the process of cancer cell invasion and metastasis. We developed a chick embryo model in which we showed that uPAR is crucial in invasion of stroma and in intravasation (breaching of the blood vessels walls). More recently and unexpectedly, uPAR-a protein anchored in the outer leaflet of the plasma membrane, has been shown to initiate signal transduction events and affect cell migration. We have shown that uPAR co-associates with fibronectin binding integrin, alpha5beta1, activates them and that this interaction leads to a greatly increased level of active ERK. When the association between uPAR and integrin or integrin and fibronectin are interrupted either by reduction of surface uPAR expression, or by other means, human carcinoma cells enter a state of protracted dormancy. We show that very high levels of active ERK are required to keep cancer cells proliferating in vivo.