Optical properties of photonic crystal slabs with asymmetrical unit cell

Using the unitarity and reciprocity properties of the scattering matrix, we analyse the symmetry and resonant optical properties of the photonic crystal slabs (PCS) with complicated unit cell. We show that the reflectivity is not changed upon the 180deg-rotation of the sample around the normal axis, even in PCS with asymmetrical unit cell. Whereas the transmissivity becomes asymmetrical if the diffraction or absorption are present. The PCS reflectivity peaks to unity near the quasiguided mode resonance for normal light incidence in the absence of diffraction, depolarisation, and absorptive losses. For the oblique incidence the full reflectivity is reached only in symmetrical PCS.Comment: 5 pages, 2 Postscript figure

Deratization Activities in the Jewish Autonomous Region in the Post-Flooding Period

Represented is a quantitative characteristic of the objects and facilities in the Jewish Autonomous Region exposed to the flooding-2013. Justified is the necessity for implementation of preventive measures against increase in the activity of HFRS natural foci; showed are the data on disinfestation organization for the prevention of natural-focal infection during the high water and post-flooding period in 2013. Displayed are the results of deratization efficacy control in various administrative units of the entity, calculated using Abbot formula, as well as results of investigation of small rodent population density at the natural stations and substantiation of the barrier disinfestation carrying out. Specified are the areas of the continuous and barrier disinfestation, indicators of Hanta Virus contamination of the rodents caught while performing control over efficacy of deratization works

Genetic Ablation of Pannexin1 Protects Retinal Neurons from Ischemic Injury

Pannexin1 (Panx1) forms large nonselective membrane channel that is implicated in paracrine and inflammatory signaling. In vitro experiments suggested that Panx1 could play a key role in ischemic death of hippocampal neurons. Since retinal ganglion cells (RGCs) express high levels of Panx1 and are susceptible to ischemic induced injury, we hypothesized that Panx1 contributes to rapid and selective loss of these neurons in ischemia. To test this hypothesis, we induced experimental retinal ischemia followed by reperfusion in live animals with the Panx1 channel genetically ablated either in the entire mouse (Panx1 KO), or only in neurons using the conditional knockout (Panx1 CKO) technology. Here we report that two distinct neurotoxic processes are induced in RGCs by ischemia in the wild type mice but are inactivated in Panx1KO and Panx1 CKO animals. First, the post-ischemic permeation of RGC plasma membranes is suppressed, as assessed by dye transfer and calcium imaging assays ex vivo and in vitro. Second, the inflammasome-mediated activation of caspase-1 and the production of interleukin-1β in the Panx1 KO retinas are inhibited. Our findings indicate that post-ischemic neurotoxicity in the retina is mediated by previously uncharacterized pathways, which involve neuronal Panx1 and are intrinsic to RGCs. Thus, our work presents the in vivo evidence for neurotoxicity elicited by neuronal Panx1, and identifies this channel as a new therapeutic target in ischemic pathologies

The First Case of <I>Yersinia Pestis</I> Subsp. <I>Pestis</I> Isolation in the Territory of Altai Mountain Natural Plague Focus. Communication 1. Microbiological Characteristics, Molecular-Genetic and Mass-Spectrometric Identification of the Isolate

Performed is a complex microbiological, molecular-genetic and mass-spectrometric identification of Yersinia pestis main ssp. strain, which was isolated for the first time in the history of surveillance over the Altai mountain natural plague focus in June, 2012. Determined is its high universal virulence. Plasmid screening, multi-locus VNTR- and mass-spectrometric analyses have revealed the strain to be more closely related to the plague agent variant, circulating in the territory of the natural focus Khuukh-Serkh-Munkh-Khairkhan, Bayan-Ul’giisk aimak, Mongolia

A Modified Consumer Inkjet for Spatiotemporal Control of Gene Expression

This paper presents a low-cost inkjet dosing system capable of continuous, two-dimensional spatiotemporal regulation of gene expression via delivery of diffusible regulators to a custom-mounted gel culture of E. coli. A consumer-grade, inkjet printer was adapted for chemical printing; E. coli cultures were grown on 750 µm thick agar embedded in micro-wells machined into commercial compact discs. Spatio-temporal regulation of the lac operon was demonstrated via the printing of patterns of lactose and glucose directly into the cultures; X-Gal blue patterns were used for visual feedback. We demonstrate how the bistable nature of the lac operon's feedback, when perturbed by patterning lactose (inducer) and glucose (inhibitor), can lead to coordination of cell expression patterns across a field in ways that mimic motifs seen in developmental biology. Examples of this include sharp boundaries and the generation of traveling waves of mRNA expression. To our knowledge, this is the first demonstration of reaction-diffusion effects in the well-studied lac operon. A finite element reaction-diffusion model of the lac operon is also presented which predicts pattern formation with good fidelity

Infection of an Individual with Plague in the Gorno-Altaisk High-Mountain Natural Focus in 2014. Communication 2. Peculiarities of Laboratory Diagnostics and Molecular-Genetic Characterization of the Isolated Strains

Laboratory diagnostics of plague was carried out in compliance with valid operational guidelines and regulations. But its peculiarity consisted in the performance of diagnostic investigations secondary to antimicrobial therapy with application of preparations characterized by the expressed activity towards gram-negative microorganisms, including the agent of plague (ceftriaxone, ciprolet, and amikacin). The studies revealed that under antibiotic treatment during the early phase of infection the most effective method for the laboratory plague diagnostics was PCR. Based on the results of the assay it was possible to establish not only provisional, but also the final diagnosis in a patient. Obtained was genetic characteristics of the strains isolated from the patient and the marmot, withdrawn at the patient’s place, using techniques of molecular-genetic analysis, in particular PCR, multilocus VNTR, and multilocus and genome-wide sequencing. Thereupon the strains were attributed to antique biovar of the main subspecies of plague agent. In addition, close relation to Y. pestis of the main subspecies isolated in the same focus in 2012 and to the strains from Mongolian Altai and Tuvinian mountain focus was determined based on phylogenetic analysis of the isolates

A boom‐or‐bust approach — the ‘Glass Cannon’ hypothesis in host microbiomes

In Focus: Dunphy, CM, Vollmer, SV, Gouhier, TC. (2021) Host–microbial systems as glass cannons: Explaining microbiome stability in corals exposed to extrinsic perturbations. Journal of Animal Ecology, 90, 1044–1057. The importance of symbiotic microbial communities for the functioning of animal hosts is now well‐documented; however, the interactions between host microbiomes and stress are less well‐understood. Dunphy et al. used a common garden experiment to show that host–microbiomes vary in their resilience across different coral species. The authors then used mathematical modelling to provide novel evidence that species with microbiomes that are regulated by host processes are robust to perturbation from stressors, but that robustness comes at a higher cost to the host. Conversely, species with microbiomes that are regulated by microbial processes are generally much more resilient and cheaper to support, but when disrupted by external stressors, the communities break down entirely—these latter species are termed ‘glass cannons’. This novel hypothesis has important implications for how host microbiomes function in a rapidly changing world that exposes animal hosts to multiple biotic and abiotic perturbations

Метаболизм триптофана при различном эффекте иммунотерапии немелкоклеточного рака легкого ингибиторами PD-1 / PD-L1

Introduction. In the structure of cancer incidence, lung cancer ranks first among men. In order to study the molecular mechanisms of the initiation and progression of lung cancer, it is necessary to study not only the tumor cells themselves, but also the features of the systemic tryptophan metabolism. Tryptophan catabolites, being to a large extent product of the metabolic activity of the intestinal microbiota, can affect the effectiveness of immunotherapy with checkpoint inhibitors. The kynurenine pathway of tryptophan metabolism is intensified in the body of cancer patients; its products have a pro-oncogenic and immunosuppressive effect, which may hinder the effectiveness of immunotherapy.Objective – to study the dynamics of changes in various metabolites of tryptophan metabolism in the blood serum and feces of patients with non-small cell lung cancer with various effects of immunotherapy with inhibitors of PD-1 (programmed cell death receptor 1) / PD-L1 (programmed cell death receptor 1 ligand).Materials and methods. The study included blood serum and stool samples obtained from 20 patients with non-small cell lung cancer treated with PD-1 / PD-L1 inhibitors. Using high-performance liquid chromatography with mass spectrometric analysis, the levels of 13 tryptophan metabolites were assessed in patients with various effects of immunotherapy. The significance of differences between the samples was assessed using a nonparametric method according to the Mann – Whitney test. They were considered statistically significant at p &lt;0.05.Results. In fecal analyzes of patients in whom a positive effect of immunotherapy was observed, baseline levels of 5-hydroxyindole acetate and quinolinic acid were lower than in patients with tumor progression. Positive clinical dynamics was accompanied by a decrease in the content of indole-3-lactate, kynurenine and indole-3-carboxaldehyde in the feces of patients. In the serum of patients with a positive response, the initial content of 5-hydroxyindole acetate, indole-3-acetate, indole-3-butyrate and quinoline acid was lower than in patients with progression of non-small cell lung cancer. A positive response to immunotherapy was characterized by an increase in the levels of indole-3-butyrate and indole-3-propionate, and a negative response was not accompanied by statistically significant changes in the studied tryptophan metabolites.Conclusion. Profiling tryptophan metabolites in feces and serum of patients with non-small cell lung cancer can be used to predict the effectiveness of immunotherapy with PD-1 / PD-L1 inhibitors.Введение. В структуре онкологической заболеваемости рак легкого занимает 1-е место среди мужчин. С целью изучения молекулярных механизмов инициации и прогрессирования рака легких необходимо исследовать не только сами опухолевые клетки, но и особенности системного метаболизма триптофана. Катаболиты триптофана, будучи в большой степени продуктами метаболической активности микробиоты кишечника, могут влиять на эффективность проведения иммунотерапии ингибиторами контрольных точек. Кинурениновый путь метаболизма триптофана интенсифицируется в организме онкологических пациентов, его продукты имеют проонкогенное и иммуносупрессивное действие, что может препятствовать эффективности иммунотерапии.Цель исследования – изучение динамики изменений различных метаболитов триптофанового обмена в сыворотке крови и кале больных немелкоклеточным раком легкого при различных эффектах иммунотерапии ингибиторами PD-1 (рецептора программируемой клеточной гибели 1) / PD-L1 (лиганда рецептора программируемой клеточной гибели 1).Материалы и методы. В исследование были включены образцы сыворотки крови и кала, полученные от 20 больных немелкоклеточным раком легкого, получавших ингибиторы PD-1 / PD-L1. С помощью высокоэффективной жидкостной хроматографии с масс-спектрометрическим анализом проведена оценка уровней 13 метаболитов триптофана у больных с различными эффектами иммунотерапии. Достоверность различий между выборками оценивали с помощью непараметрического метода по критерию Манна–Уитни. Они считались статистически значимыми при р &lt;0,05.Результаты. В анализах кала пациентов, у которых наблюдали положительный эффект от иммунотерапии, исходные уровни 5-гидроксииндолацетата и хинолиновой кислоты были ниже, чем у больных с прогрессированием опухоли. Положительная клиническая динамика сопровождалась снижением содержания индол-3-лактата, кинуренина и индол-3-карбоксальдегида в анализах кала больных. В сыворотке пациентов с положительным ответом исходное содержание 5-гидроксииндолацетата, индол-3-ацетата, индол-3-бутирата и хинолиновой кислоты оказалось ниже, чем у пациентов с прогрессированием немелкоклеточного рака легкого. Положительный ответ на иммунотерапию характеризовался повышением уровней индол-3-бутирата и индол-3-пропионата, а отрицательный – не сопровождался статистически значимыми изменениями исследованных триптофановых метаболитов.Заключение. Профилирование метаболитов триптофана в кале и сыворотке больных немелкоклеточным раком легкого может быть использовано для прогнозирования эффективности иммунотерапии ингибиторами PD-1 / PD-L1

Sunlight-Exposed Biofilm Microbial Communities Are Naturally Resistant to Chernobyl Ionizing-Radiation Levels

BACKGROUND: The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. CONCLUSIONS/SIGNIFICANCE: Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general diversity patterns, despite increased mutation levels at the single-OTU level. Therefore, biofilm communities growing in sunlight exposed substrates are capable of coping with increased mutation rates and appear pre-adapted to levels of ionizing radiation in Chernobyl due to their natural adaptation to periodical desiccation and ambient UV radiation