Bioelectrochemistry and the Singularity Point “I Robot”?**

In his book “The Singularity Is Near: When Humans Transcend Biology” Ray Kurtzweil described the concept of artificial intelligence in an unorthodox way. It describes how humans will interface with machines and eventually will become one with machines. Hence, we can define a time point, which is a theoretical point when humans and machines will become one. In order to reach this point, a successful interface between the biological/organic to the inorganic matter is needed. In order for these pieces of “machinery” to communicate between one another, an exchange of matter and energy should be achieved. Electron transfer between the inorganic and organic has been the mission of bioelectrochemical systems in the past few decades. Enzymes, antibodies and nucleic acids attachment to electrodes has been achieved more than three decades ago. In the following assay I am reviewing the different advances that were made towards an integration between biological entities to inorganic ones.     

TULP1 and TUB Are Required for Specific Localization of PRCD to Photoreceptor Outer Segments

Photoreceptor disc component (PRCD) is a small protein which is exclusively localized to photoreceptor outer segments, and is involved in the formation of photoreceptor outer segment discs. Mutations in PRCD are associated with retinal degeneration in humans, mice, and dogs. The purpose of this work was to identify PRCD-binding proteins in the retina. PRCD protein-protein interactions were identified when implementing the Ras recruitment system (RRS), a cytoplasmic-based yeast two-hybrid system, on a bovine retina cDNA library. An interaction between PRCD and tubby-like protein 1 (TULP1) was identified. Co-immunoprecipitation in transfected mammalian cells confirmed that PRCD interacts with TULP1, as well as with its homolog, TUB. These interactions were mediated by TULP1 and TUB highly conserved C-terminal tubby domain. PRCD localization was altered in the retinas of TULP1- and TUB-deficient mice. These results show that TULP1 and TUB, which are involved in the vesicular trafficking of several photoreceptor proteins from the inner segment to the outer segment, are also required for PRCD exclusive localization to photoreceptor outer segment discs.     

Impaired Functional Connectivity Underlies Fragile X Syndrome

Fragile X syndrome (FXS), the most common form of inherited intellectual disability, is caused by a developmentally regulated silencing of the FMR1 gene, but its effect on human neuronal network development and function is not fully understood. Here, we isolated isogenic human embryonic stem cell (hESC) subclones—one with a full FX mutation and one that is free of the mutation (control) but shares the same genetic background—differentiated them into induced neurons (iNs) by forced expression of NEUROG-1, and compared the functional properties of the derived neuronal networks. High-throughput image analysis demonstrates that FX-iNs have significantly smaller cell bodies and reduced arborizations than the control. Both FX- and control-neurons can discharge repetitive action potentials, and FX neuronal networks are also able to generate spontaneous excitatory synaptic currents with slight differences from the control, demonstrating that iNs generate more mature neuronal networks than the previously used protocols. MEA analysis demonstrated that FX networks are hyperexcitable with significantly higher spontaneous burst-firing activity compared to the control. Most importantly, cross-correlation analysis enabled quantification of network connectivity to demonstrate that the FX neuronal networks are significantly less synchronous than the control, which can explain the origin of the development of intellectual dysfunction associated with FXS.     

Corrosion Characterization: Use of Raman Spectroscopy for Failure Analysis

A self-locking nut was received for inspection as part of the IAF’s standard quality assurance procedure. A metallurgical cross section was taken, and upon optical microscopic observation, crack-like defects filled with what appeared to be oxides were observed close to the surface of the nut. In order to determine if the defects are folds created during forging, Raman spectroscopy was used to analyze the oxides. The analysis was based on two important properties of Iron oxides: Different oxides are created at different temperatures, each having distinct Raman spectrum. By comparing Raman spectrums from the literature to the ones obtained experimentally, it was determined that the defects originated in the manufacturing process, most likely during forging.     

Ion track-based urea sensing

A highly sensitive urea biosensor is described. We employed polymer foils which are thin, swift heavy ion-irradiated polycarbonate foils, followed by etching. The examined geometrical arrangement is of 1 foil, two compartments system. One electrode is placed in each compartment and a sinusoidal voltage is applied to the system. The enzyme urease is attached to the inner walls of the etched ion tracks in the foil, and one of the compartments is filled with urea solution of variable concentrations which can then interact with the enzyme, resulting in a change of track resistance. These results are compared with those obtained using a simple, non-confined urea/urease mixture. We report that this strategy, where the enzyme is bound to the etched track walls, is very efficient, as it demonstrates very high sensitivity. In this system, urea can be detected at a concentration as low as 1 × 10⁻⁷ M. The sensor is, moreover, still active at a concentration of 1 M urea. The currents associated with each concentration differ by a factor of 10.     

Automatic comparisons of artificial digits never compared: Learning linear ordering relations.

In 2 experiments, participants were trained to perform magnitude decisions, that is, decide which of 2 arbitrary symbols in a pair represented a larger magnitude. The symbols corresponded to locations on an implicit linear scale. Training resulted in a Stroop-like size congruity effect when the participants had to decide which symbol in a pair was physically larger. This effect, showing automaticity of the processing of magnitude relations, was also obtained for pairs never encountered during practice. The implications of these findings for processing of magnitude relations and for theories of automaticity are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Complexity of NAC Action as an Antidiabetic Agent: Opposing Effects of Oxidative and Reductive Stress on Insulin Secretion and Insulin Signaling

Dysregulated redox balance is involved in the pathogenesis of type 2 diabetes. While the benefit of antioxidants in neutralizing oxidative stress is well characterized, the potential harm of antioxidant-induced reductive stress is unclear. The aim of this study was to investigate the dose-dependent effects of the antioxidant N-acetylcysteine (NAC) on various tissues involved in the regulation of blood glucose and the mechanisms underlying its functions. H₂O₂ was used as an oxidizing agent in order to compare the outcomes of oxidative and reductive stress on cellular function. Cellular death in pancreatic islets and diminished insulin secretion were facilitated by H₂O₂-induced oxidative stress but not by NAC. On the other hand, myotubes and adipocytes were negatively affected by NAC-induced reductive stress, as demonstrated by the impaired transmission of insulin signaling and glucose transport, as opposed to H₂O₂-stimulatory action. This was accompanied by redox balance alteration and thiol modifications of proteins. The NAC-induced deterioration of insulin signaling was also observed in healthy mice, while both insulin secretion and insulin signaling were improved in diabetic mice. This study establishes the tissue-specific effects of NAC and the importance of the delicate maintenance of redox balance, emphasizing the challenge of implementing antioxidant therapy in the clinic.