Tonometry and the Imbert-Fick Law

Tonometry is the measurement of the pressure in the fluid contained within the globe of the eye. The search for this measurement has been a continuing exercise for a century.     

Comparative early and late outcomes after primary percutaneous coronary intervention in ST-segment elevation and non-ST-segment elevation acute myocardial infarction (from the CADILLAC trial)

We determined the outcomes of patients with acute ST-segment elevation (STE) myocardial infarction (STEMI) and non-STEMI (NSTEMI) after primary percutaneous coronary intervention (PCI). The prognosis after primary PCI in STEMI has been extensively studied and defined. Outcomes of patients who undergo primary PCI for NSTEMI are less well established. In total, 2,082 patients with ongoing chest pain for > 30 minutes consistent with acute MI were randomized to balloon angioplasty versus stenting, each with/without abciximab. Of 1,964 patients, STEMI was present in 1,725 (87.8%) and NSTEMI in 239 (12.2%). Compared with STEMI, those with NSTEMI were more likely to have delayed time-to-hospital arrival (2.4 vs 1.8 hours, p = 0.0002) and increased door-to-balloon time (3.2 vs 1.9 hours, p < 0.0001). Patients with NSTEMI were more likely to have Thrombolysis In Myocardial Infarction grade 3 flow at baseline (37.3% vs 19.4%, p < 0.0001) and higher ejection fraction (58.7% vs 55.8%, p = 0.001), but similar rates of postprocedural Thrombolysis In Myocardial Infarction grade 3 flow. At 1 year, patients with NTEMI had similar mortality (3.4% vs 4.4%, p = 0.40) but higher rates of major adverse cardiac events (24.0% vs 16.6%, p = 0.007) that was driven by more frequent ischemic target vessel revascularization (21.8% vs 11.9%, p <0.0001). In conclusion, patients with acute MI without STE who are treated with primary PCI have marked delays to treatment, similar late mortality, and increased rates of ischemic target vessel revascularization compared with patients with STEMI, despite more favorable angiographic features at presentation and similar reperfusion success. The adverse prognosis of patients with NSTEMI should be recognized and efforts made to decrease reperfusion times.     

Cardiovascular disease in the polycystic ovary syndrome: new insights and perspectives

The new millennium has brought intense focus of interest on the risk of cardiovascular disease in women. The polycystic ovary syndrome (PCOS) is a common endocrine disorder in women characterised by hyperandrogenism and oligomenorrhoea. Most women with PCOS also exhibit features of the metabolic syndrome, including insulin resistance, obesity and dyslipidaemia. While the association with type 2 diabetes is well established, whether the incidence of cardiovascular disease is increased in women with PCOS remains unclear. Echocardiography, imaging of coronary and carotid arteries, and assessments of both endothelial function and arterial stiffness have recently been employed to address this question. These studies have collectively demonstrated both structural and functional abnormalities of the cardiovascular system in PCOS. These alterations, however, appear to be related to the presence of individual cardiovascular risk factors, particularly insulin resistance, rather than to the presence of PCOS and hyperandrogenaemia per se. However, given the inferential nature of the evidence to date, more rigorous cohort studies of long-term cardiovascular outcomes and clinical trials of risk factor modification are required in women with PCOS.     

Effect of a Vitamin D<Subscript>3</Subscript> derivative (B3CD) with postulated anti-cancer activity in an ovarian cancer animal model

The objective of the present study was to test the hypothesis that Calcidiol derivative B3CD qualifies as a potential anti-cancer drug in vivo employing an ovarian cancer xenograft model in mice. In addition, the selectivity of B3CD on viability and proliferation of platinum-resistant human ovarian cancer cell lines in comparison to control cell lines was analyzed in vitro. B3CD displayed cell line-specific cytotoxicity screened against a panel of ovarian and other carcinoma cell lines, endothelial and control cells. B3CD, at sub-cytotoxic concentrations, revealed stronger effects on the proliferation of SKOV-3 ovarian cancer cells vs. primary fibroblasts as determined by BrdU incorporation analysis. Treatment with B3CD at 0.5 μM resulted in highly condensed chromatin and fragmented nuclei in SKOV-3 cells but not in primary fibroblasts. B3CD induced cell death at low drug concentrations (≤0.5 μM) in SKOV-3 ovarian cancer cells is mediated by the p38 MAPK signaling pathway: B3CD induced p38 MAPK expression and activation in SKOV-3 cells and inhibition of p38 signaling counteracted B3CD induced cell death in vitro. An ovarian cancer cell animal model (human SKOV-3 cell derived xenografts in nude mice) revealed that tumor growth in few B3CD treated mice accelerated while the majority of B3CD treated mice displayed delayed tumor growth or full tumor regression. B3CD possesses anti-ovarian cancer properties in vitro and in vivo. We propose the further development of non-calcemic bromoacetoxy derivatives of vitamin D₃ as potential anti-cancer therapeutics.     

In vivo molecular imaging of peripheral amyloidosis using heparin-binding peptides

Heparan sulfate proteoglycans (HSPGs) are ubiquitous components of pathologic amyloid deposits in the organs of patients with disorders such as Alzheimer's disease or systemic light chain (AL) or reactive (AA) amyloidosis. Molecular imaging methods for early detection are limited and generally unavailable outside the United Kingdom. Therefore, there is an urgent need to develop novel, specific amyloidophilic radiotracers for imaging to assist in diagnosis, prognostication, and monitoring response to therapy. Amyloid-associated HSPG can be differentiated from HSPG found in surrounding healthy cells and tissues by the preferential binding of certain HS-reactive single chain variable fragments and therefore, represents a biomarker that can be targeted specifically with appropriate reagents. Using a murine model of AA amyloidosis, we have examined the in vivo amyloid reactivity of seven heparin-binding peptides by using single photon emission and X-ray computed tomographic imaging, microautoradiography, and tissue biodistribution measurements. All of the peptides bound amyloid deposits within 1 h post-injection, but the extent of the reactivity differed widely, which was evidenced by image quality and grain density in autoradiographs. One radiolabeled peptide bound specifically to murine AA amyloid in the liver, spleen, kidney, adrenal, heart, and pancreas with such avidity that it was observed in single photon emission tomography images as late as 24 h post-injection. In addition, a biotinylated form of this peptide was shown histochemically to bind human AA, ALκ, ALλ, transthyretin amyloidosis (ATTR), and Aβ amyloid deposits in tissue sections. These basic heparin-binding peptides recognize murine and human amyloid deposits in both in vivo and ex vivo tissues and therefore, have potential as radiotracers for the noninvasive molecular imaging of amyloid deposits in situ.