"Inverted Tako-Tsubo": transient apical-sparing cardiomyopathy

We present a case of "inverted Tako-Tsubo" syndrome in a pre-menopausal woman with normal coronary arteries. Transient basal myocardial akinesia and ECG findings of healed myocardial infarction appeared shortly after emotional stress and resolved completely 4 days later.     

Insulin-like growth factor-I receptor (IGF-IR) targeting with monoclonal antibody cixutumumab (IMC-A12) inhibits IGF-I action in endometrial cancer cells

Specific insulin-like growth factor-I receptor (IGF-IR) targeting emerged in recent years as a promising therapeutic strategy in cancer. Endometrial cancer is the most common gynaecological cancer in the Western world. The aim of this study was to evaluate the potential of cixutumumab (IMC-A12, ImClone Systems), a fully human monoclonal antibody against the IGF-IR, to inhibit IGF-I-mediated biological actions and cell signalling events in four endometrial carcinoma-derived cell lines (ECC-1, Ishikawa, USPC-1 and USPC-2). Our results demonstrate that cixutumumab was able to block the IGF-I-induced autophosphorylation of the IGF-IR. In addition, the PI3K and MAPK downstream signalling pathways were also inactivated by cixutumumab in part of the cell lines. Prolonged (24 h and 48 h) exposures to cixutumumab reduced IGF-IR expression. Furthermore, confocal microscopy of GFP-tagged receptors shows that cixutumumab treatment led to IGF-IR redistribution from the cell membrane to the cytoplasm. Antiapoptotic effects were evaluated by cleavage of caspase 3 and PARP, and mitogenicity and transformation by proliferation and cell cycle assays. Results obtained showed that cixutumumab abrogated the IGF-I-stimulated increase in proliferation rate, and increased caspase-3 and PARP cleavage, two markers of apoptosis. Of importance, cixutumumab had no effect neither on insulin receptor (IR) expression nor on IGF-I activation of IR. In summary, in a cellular model of endometrial cancer cixutumumab was able to inhibit the IGF-I-induced activation of intracellular cascades, apoptosis and proliferation.     

Role and regulation of PI3K in sperm capacitation and the acrosome reaction

Mammalian spermatozoa undergo several signaling and biochemical transformations in the female genital tract, collectively called capacitation. The capacitated spermatozoon binds to the egg zona pellucida, where it undergoes the acrosome reaction (AR), a process enabling it to penetrate and fertilize the egg. Actin polymerization occurs in sperm capacitation and depolymerization prior to the AR. In this review we describe the possible role and regulation of PI3K in sperm capacitation and the acrosome reaction. We claim that PI3K is activated by protein kinase A and suppressed by protein kinase C. Only partial activation of PI3K is seen during the capacitation time, however towards the end of incubation, full activation is observed. Actin polymerization during capacitation is independent on PI3K activity, suggesting that the enzyme is not involved in sperm capacitation. However, the full activation of PI3K towards the end of the capacitation suggests that it might mediate the AR, as indeed was found.     

Evaluation of the <Superscript>13</Superscript>C-Octanoate Breath Test as a Surrogate Marker of Liver Damage in Animal Models

Background  

Octanoate (also known as sodium octanoate), a medium-chain fatty acid metabolized in the liver, is a potential substrate for non-invasive breath testing of hepatic mitochondrial β-oxidation.     

Optically Controlled Supercapacitors: Functional Active Carbon Electrodes with Semiconductor Particles

Supercapacitors, S-C—capacitors that take advantage of the large capacitance at the interface between an electrode and an electrolyte—have found many short-term energy applications. The parallel plate cells were made of two transparent electrodes (ITO), each covered with a semiconductor-embedded, active carbon (A-C) layer. While A-C appears black, it is not an ideal blackbody absorber that absorbs all spectral light indiscriminately. In addition to a relatively flat optical absorption background, A-C exhibits two distinct absorption bands: in the near-infrared (near-IR and in the blue. The first may be attributed to absorption by the OH⁻ group and the latter, by scattering, possibly through surface plasmons at the pore/electrolyte interface. Here, optical and thermal effects of sub-μm SiC particles that are embedded in A-C electrodes, are presented. Similar to nano-Si particles, SiC exhibits blue band absorption, but it is less likely to oxidize. Using Charge-Discharge (CD) experiments, the relative optically related capacitance increase may be as large as ~34% (68% when the illuminated area is taken into account). Capacitance increase was noted as the illuminated samples became hotter. This thermal effect amounts to <20% of the overall relative capacitance change using CD experiments. The thermal effect was quite large when the SiC particles were replaced by CdSe/ZnS quantum dots; for the latter, the thermal effect was 35% compared to 10% for the optical effect. When analyzing the optical effect one may consider two processes: ionization of the semiconductor particles and charge displacement under the cell’s terminals—a dipole effect. A model suggests that the capacitance increase is related to an optically induced dipole effect.