SLO Fundus Imaging Is the Most Sensitive Modality of Multimodal Imaging for Macular Microembolisms with Subtle Signs

Background. Microemboli of fat or other material into the terminal macular retinal circulation can be difficult to diagnose. We report 2 cases that showed subtle signs where SLO fundus imaging was most sensitive to precisely outline the limits of the inner retina infarction. Patients and Methods. Multimodal imaging analysis was performed including fundus photography, fluorescein angiography, indocyanine green angiography, Optical Coherence Tomography and SLO fundus imaging of 2 cases with suspected infarction of the inner retina. Cases. A 30-year-old man reported a grey central spot OD a few days after being squeezed between two cars with a sacrum fracture. Vision was 0.2 OD, and 1.0 OS. Examination was unremarkable and fluorescein angiography was normal. Octopus visual field showed a tiny central scotoma OD. Microperimetry showed decreased central sensitivity OD > OS. The only sign was a dark area on the SLO fundus picture indicating a subtle infarction of the inner retina (OD > OS) with nothing visible on the OCT. Resolution of lesions on the SLO picture ODS occurred in parallel with improvement of microperimetry and visual acuity. A 32-year-old woman suspected to take IV drugs had a sudden drop of vision to 0.4 OD and count fingers at 6 feet OS. Signs included macular hemorrhages and non perfusion on FA. The striking sign was a large dark area on the SLO picture precisely delineating the more extensive infarcted area of internal retina corresponding to OCT hyperreflectivity, visible in this case. Conclusions. Macular ischemia due to microemboli can show obvious fundus signs as hemorrhages, cotton wool spots and non perfusion or can present in a subclinical fashion. The SLO picture has a higher image contrast and higher resolution compared to conventional fundus photography and so can precisely delineate ischemic changes of the inner retina causing the unexplained visual loss.

Induction of apoptosis in p16INK4A mutant cell lines by adenovirus-mediated overexpression of p16INK4A protein

The tumor suppressor gene p16INK4A is a cyclin-dependent kinase inhibitor (CDKI) and an important cell cycle regulator. We have previously constructed a recombinant adenovirus which expresses p16 (Adp16) and shown that infection in a variety of human tumor cell lines with this recombinant virus results in high levels of p16INK4A protein expression resulting in cell cycle arrest and loss of cyclin-cdk activity. Furthermore, adenoviral-mediated overexpression of wild-type p16INK4A is more toxic in cancer cells which express mutant forms of p16INK4A compared to cancer cell lines containing endogenous wild-type p16. TUNEL assay and DAPI staining following infection of MDA-MB 231 breast cancer cells with Adp16 indicate that p16INK4A-mediated cytotoxicity was associated with apoptosis. This is supported by studies demonstrating a decrease in cpp32 and cyclinB1 protein levels and induction of poly (ADP-ribose) polymerase (PARP) cleavage following infection of MDA-MB-231 cells with Adp16. These results suggest that gene therapy using Adp16 may be a promising treatment option for human cancers containing alterations in p16 expression.

Liquid crystal thermography. A method for monitoring temperature gradients in microtitration plates

Precise quantitative heat transfer information in microtitration plates can be obtained by filling the wells of a microtitration plate with cholesteric liquid crystals and incubating the plates at the desired temperature in different incubators. The liquid crystals indicate temperature by changes in discrete reproducible colors over various temperature ranges. With these instrumented plates, interwell thermal gradients may be documented visually and are in close agreement with results obtained by using wire thermocouple measuring techniques.