Information Conversion in Measuring Channels with Optoelectronic Sensors.

The purpose of this work is the authors' attempt to identify the main phases of information transformation in measurement channels on the example of an optical measurement channel with microprocessor control. The authors include such phases: hardware implementation and analytical representation of an optical sensor's converting functions and a current-to-voltage converter; based on the methods of experimental computer science, the converting functions and sensitivity are deduced, analytical dependences for estimation of a range of measurement are obtained. It is shown that the choice of information transmission type in the microprocessor measuring channel significantly affects the speed of the measuring channel. Based on the uncertainty in the form of entropy before and after measurements, the amount of information for measuring channels with optoelectronic sensors is estimated. The application of the results obtained in the work allows even at the design stage of physical and mathematical modeling to assess the basic static metrological characteristics of measuring channels, aimed at reducing the stage of development and debugging of hardware and software and standardization of their metrological characteristics.

Innate and intrinsic antiviral immunity in Drosophila.

The fruit fly Drosophila melanogaster has been a valuable model to investigate the genetic mechanisms of innate immunity. Initially focused on the resistance to bacteria and fungi, these studies have been extended to include antiviral immunity over the last decade. Like all living organisms, insects are continually exposed to viruses and have developed efficient defense mechanisms. We review here our current understanding on antiviral host defense in fruit flies. A major antiviral defense in Drosophila is RNA interference, in particular the small interfering (si) RNA pathway. In addition, complex inducible responses and restriction factors contribute to the control of infections. Some of the genes involved in these pathways have been conserved through evolution, highlighting loci that may account for susceptibility to viral infections in humans. Other genes are not conserved and represent species-specific innovations.

Endemic Mimosa species from Mexico prefer alphaproteobacterial rhizobial symbionts.

The legume genus Mimosa has > 500 species, with two major centres of diversity, Brazil (c. 350 spp.) and Mexico (c. 100 spp.). In Brazil most species are nodulated by Burkholderia. Here we asked whether this is also true of native and endemic Mexican species. We have tested this apparent affinity for betaproteobacteria by examining the symbionts of native and endemic species of Mimosa in Mexico, especially from the central highlands where Mimosa spp. have diversified. Nodules were tested for betaproteobacteria using in situ immunolocalization. Rhizobia isolated from the nodules were genetically characterized and tested for their ability to nodulate Mimosa spp. Immunological analysis of 25 host taxa suggested that most (including all the highland endemics) were not nodulated by betaproteobacteria. Phylogenetic analyses of 16S rRNA, recA, nodA, nodC and nifH genes from 87 strains isolated from 20 taxa confirmed that the endemic Mexican Mimosa species favoured alphaproteobacteria in the genera Rhizobium and Ensifer: this was confirmed by nodulation tests. Host phylogeny, geographic isolation and coevolution with symbionts derived from very different soils have potentially contributed to the striking difference in the choice of symbiotic partners by Mexican and Brazilian Mimosa species.

Cross-species analysis of viral nucleic acid interacting proteins identifies TAOKs as innate immune regulators.

The cell intrinsic antiviral response of multicellular organisms developed over millions of years and critically relies on the ability to sense and eliminate viral nucleic acids. Here we use an affinity proteomics approach in evolutionary distant species (human, mouse and fly) to identify proteins that are conserved in their ability to associate with diverse viral nucleic acids. This approach shows a core of orthologous proteins targeting viral genetic material and species-specific interactions. Functional characterization of the influence of 181 candidates on replication of 6 distinct viruses in human cells and flies identifies 128 nucleic acid binding proteins with an impact on virus growth. We identify the family of TAO kinases (TAOK1, -2 and -3) as dsRNA-interacting antiviral proteins and show their requirement for type-I interferon induction. Depletion of TAO kinases in mammals or flies leads to an impaired response to virus infection characterized by a reduced induction of interferon stimulated genes in mammals and impaired expression of srg1 and diedel in flies. Overall, our study shows a larger set of proteins able to mediate the interaction between viral genetic material and host factors than anticipated so far, attesting to the ancestral roots of innate immunity and to the lineage-specific pressures exerted by viruses.

Implication of human herpesviruses in oncogenesis through immune evasion and supression.

All human herpesviruses (HHVs) have been implicated in immune system evasion and suppression. Moreover, two HHV family members, i.e. EBV and KSHV, are recognised as oncogenic viruses. Our literature review summarises additional examples of possible oncogenic mechanisms that have been attributed to other HHVs. In general, HHVs affect almost every cancer-implicated branch of the immune system, namely tumour-promoting inflammation, immune evasion, and immunosuppression. Some HHVs accomplish these effects by inhibiting apoptotic pathways and by promoting proliferation. Mechanisms related to immunosupression and low grade chronic inflammation could eventually result in the initiation and progression of cancer. In this article we open a discussion on the members of Herpesviridae, their immune evasion and suppression mechanisms, and their possible role in cancer development. We conclude that discerning the mechanisms of interplay between HHV, immune system, and cancer is essential for the development of novel preventative and therapeutic approaches for cancer treatment and prophylaxis.

Role of viruses in the development of breast cancer.

The most common cancer worldwide among women is breast cancer. The initiation, promotion, and progression of this cancer result from both internal and external factors. The International Agency for Research on Cancer stated that 18-20% of cancers are linked to infection, and the list of definite, probable, and possible carcinogenic agents is growing each year. Among them, biological carcinogens play a significant role. In this review, data covering infection-associated breast and lung cancers are discussed and presented as possible involvements as pathogens in cancer. Because carcinogenesis is a multistep process with several contributing factors, we evaluated to what extent infection is significant, and concluded that members of the herpesvirus, polyomavirus, papillomavirus, and retrovirus families definitely associate with breast cancer. Detailed studies of viral mechanisms support this conclusion, but have presented problems with experimental settings. It is apparent that more effort needs to be devoted to assessing the role of these viruses in carcinogenesis, by characterizing additional confounding and synergistic effects of carcinogenic factors. We propose that preventing and treating infections may possibly stop or even eliminate certain types of cancers.

Childhood cancers: what is a possible role of infectious agents?

The etiology of childhood cancers has been studied for more than 40 years. However, most if not all cancers occurring in children are attributed to unknown causes. This review is focused on the role of infections in cancer development and progression in children. The main infectious agents include human herpesviruses, polyoma viruses, and human papilloma viruses. It is known that infections can lead to carcinogenesis through various mechanisms, and most likely act in addition to genetic and environmental factors. Given the importance of the infectious etiology of childhood cancers, clinical implications and possible prevention strategies are discussed.

Using antimicrobial adjuvant therapy in cancer treatment: a review.

Recent clinical and pre-clinical data demonstrate that adjuvant antimicrobial therapy is beneficial in cancer treatment. There could be several reasons for this effect, which include treating cancer associated bacteria and viruses, prophylaxis of post-chemotherapy infections due to immunosuppression, and antiproliferative effect of certain antimicrobials. Targeting cancer associated viruses and bacteria with antimicrobial agents is currently used for gastric, cervical, hematopoietic, liver and brain cancer. However this treatment is effective only in combination with conventional therapies. Antimicrobials can also have a direct antiproliferative and cytotoxic effect, and can cause apoptosis. Moreover, some antimicrobials are known to be helpful in overcoming side effects of drugs commonly used in cancer treatment. Chemotherapy related bacteremia and neutropenia can be overcome by the appropriately timed use of antimicrobials. This review summarizes the data on the effects of antivirals and antibiotics on cancer treatment and describes their mechanisms.