Hydrogen peroxide induced by modulated electromagnetic radiation protects the cells from DNA damage

It is believed that non-ionizing electromagnetic radiation (EMR) and low-level hydrogen peroxide (H₂O₂) may change nonspecific resistance and modify DNA damage caused by ionizing radiation. To check this assumption, the combined effects of extremely high-frequency EMR (EHF EMR) and X-rays on induction of DNA damage in mouse whole blood leukocytes were studied. The cells were exposed to X-rays with or without preliminary treatment with EHF EMR or low-level H₂O₂. With the use of enhanced chemiluminescence, it was shown for the first time that pulse-modulated EHF EMR (42.2 GHz, incident power density of 0.1 mW/cm², exposure duration of 20 min, modulation frequency of 1 Hz) induced H₂O₂ at a concentration of 4.6 ± 0.3 nM L^?1 in physiological saline. With the use of an alkaline comet assay, it was found that the exposure of cells to the pulse-modulated EHF EMR, 25 min prior to treatment with X-rays at a dose of 4 Gy reduced the level of ionizing radiation-induced DNA damage. Continuous EHF EMR was inefficient. In turn, it was shown that low-level H₂O₂ (30–500 nM L^?1) protected the cells against X-irradiation. Thus, the mechanisms of radiation protective effect of EHF EMR are connected with the induction of the adaptive response by nanomolar concentrations of reactive oxygen species formed by pulse-modulated EHF EMR.     

The First Observation of Memory Effects in the InfraRed (FT-IR) Measurements: Do Successive Measurements Remember Each Other?

Over the past couple of decades there have been major advances in the field of nanoscience and nanotechnology. Many applications have sprouted from these fields of research. It is essential, given the scale of the materials, to attain accurate, valid and reproducible measurements. Material properties have shown to be a function of their size and composition. Physiochemical properties of the nanomaterials can significantly alter material behavior compared to bulk counterparts. For example, metal oxide nanoparticles have found broad applications ranging from photo-catalysis to antibacterial agents. In our study, we synthesized CuO nanoparticles using well established sol-gel based methods with varying levels of Ni doping. However, upon analysis of measured infrared data, we discovered the presence of quasi-periodic (QP) processes. Such processes have previously been reported to be tightly associated with measurement memory effects. We were able to detect the desired QP process in these measurements from three highly accurate repetitive experiments performed on each Ni (1–7%) doped CuO sample. In other words, successive measurements performed in a rather short period of time remember each other at least inside a group of neighboring measurements.     

Insulin receptor-related receptor as an extracellular pH sensor involved in the regulation of acid–base balance

Recent studies of insulin receptor-related receptor (IRR) revealed its unusual property to activate upon extracellular application of mildly alkaline media, pH > 7.9. The activation of IRR with hydroxyl anion has typical features of ligand–receptor interaction; it is specific, dose-dependent, involves the IRR extracellular domain and is accompanied by a major conformational change. IRR is a member of the insulin receptor minifamily and has been long viewed as an orphan receptor tyrosine kinase since no peptide or protein agonist of IRR was found. In the evolution, IRR is highly conserved since its divergence from the insulin and insulin-like growth factor receptors in amphibia. The latter two cannot be activated by alkali. Another major difference between them is that unlike ubiquitously expressed insulin and insulin-like growth factor receptors, IRR is found in specific sets of cells of only some tissues, most of them being exposed to extracorporeal liquids of extreme pH. In particular, largest concentrations of IRR are in beta-intercalated cells of the kidneys. The primary physiological function of these cells is to excrete excessive alkali as bicarbonate into urine. When IRR is removed genetically, animals loose the property to excrete bicarbonate upon experimentally induced alkalosis. In this review, we will discuss the available in vitro and in vivo data that support the hypothesis of IRR role as a physiological alkali sensor that regulates acid–base balance. This article is part of a Special Issue entitled: Emerging recognition and activation mechanisms of receptor tyrosine kinases.     

EGFR Mutation-Induced Alternative Splicing of Max Contributes to Growth of Glycolytic Tumors in Brain Cancer

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Synthesis and Properties of O-β-D-Ribofuranosyl-(1″-2′)-Adenosine-5″-O-Phosphate and Its Derivatives

Abstract

The synthesis of O-β-D-ribofuranosyl-(1″-2′)-adenosine-5″-O-phosphate and its suitably protected derivative for oligonucleotide synthesis have been developed.     

Development of a Highly Protective Combination Monoclonal Antibody Therapy against Chikungunya Virus

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes global epidemics of a debilitating polyarthritis in humans. As there is a pressing need for the development of therapeutic agents, we screened 230 new mouse anti-CHIKV monoclonal antibodies (MAbs) for their ability to inhibit infection of all three CHIKV genotypes. Four of 36 neutralizing MAbs (CHK-102, CHK-152, CHK-166, and CHK-263) provided complete protection against lethality as prophylaxis in highly susceptible immunocompromised mice lacking the type I IFN receptor (Ifnar^−/−) and mapped to distinct epitopes on the E1 and E2 structural proteins. CHK-152, the most protective MAb, was humanized, shown to block viral fusion, and require Fc effector function for optimal activity in vivo. In post-exposure therapeutic trials, administration of a single dose of a combination of two neutralizing MAbs (CHK-102+CHK-152 or CHK-166+CHK-152) limited the development of resistance and protected immunocompromised mice against disease when given 24 to 36 hours before CHIKV-induced death. Selected pairs of highly neutralizing MAbs may be a promising treatment option for CHIKV in humans.     

The Chinese species of the genus Ontsira Cameron (Hymenoptera,Braconidae, Doryctinae)

The Chinese species of the genus Ontsira Cameron, 1900 (Hymenoptera: Braconidae, Doryctinae) are reviewed. Eleven species are recognized, of which four new species are described from China and South Korea: O. abbreviata sp. n., O. henana sp. n., O. robusta sp. n., and O. rugivertex sp. n. Two species, O. ignea (Ratzeburg) and O. neantica Belokobylskij et Maetô, are recorded in China for the first time. A key to the Asian species of the genus Ontsira is provided.     

At home among strangers: Alfred Russel Wallace in Russia

Alfred Russel Wallace (1823–1913) was an influential figure within Russian pre-Synthetic evolutionary biology, i.e. the time period before the Synthetic Theory of Evolution was established (ca. 1880–1930s). His major works were translated into Russian and his general ideas were read and discussed by both insiders and outsiders of scientific evolutionism. At the same time, Wallace played a controversial role in the growth of Darwinism in Russia, and Charles Robert Darwin (1809–1882) has eclipsed Wallace in his influence on Russian evolutionary thinking. In this paper we briefly outline Wallace’s impact on Russian pre-Synthetic scientific evolutionism and its general intellectual climate. We demonstrate that both Russian pro-Darwinian evolutionists and anti-Darwinians (scientific anti-Darwinians as well as creationists) were fully aware of Wallace’s contributions to the development of evolutionary theory. Yet, Wallace’s radical selectionism, as well as his controversial arguments for “design in nature”, predetermined his special place within the Russian intellectual landscape.