Optimization of an organic memristor as an adaptive memory element

The combination of memory and signal handling characteristics of a memristor makes it a promising candidate for adaptive bioinspired information processing systems. This poses stringent requirements on the basic device, such as stability and reproducibility over a large number of training/learning cycles, and a large anisotropy in the fundamental control material parameter, in our case the electrical conductivity. In this work we report results on the improved performance of electrochemically controlled polymeric memristors, where optimization of a conducting polymer polyaniline in the active channel and better environmental control of fabrication methods led to a large increase both in the absolute values of the conductivity in the partially oxydized state of polyaniline and of the on-off conductivity ratio. These improvements are crucial for the application of the organic memristor to adaptive complex signal handling networks

Evaluation of different lighting sources on the growth and chemical composition of lettuce

ArticleExperiment were carried out in Latvia University of Agriculture in plant growth room. Lettuce Lactuca sativa L. var foliosum cv. ‘Dubacek’ and L . sativa L. cv. ‘Michalina’ were grown under 4 types of lights (luminescence lamps, commercial light emitting diodes (LED) lamps (V - TAC premium series – for plant growing) and two different Lumigrow LED strips - dominant wavelength - blue or red with 14 h ph otoperiod and total photosynthetic active radiation (PAR) 100 μmol m - 2 s - 1 in all variants. Plant weight, length, amount of leaves were measured. Content of chlorophylls, carotenoids, phenols, flavonoids in lettuce was determined three times per vegetation period. In experiments were found that higher lettuce yield was under commercial LED (V - TAC premium series), but these plants contain less soluble sugars, pigments and phenols. Better plant quality was obtained with luminescence lamps. These lettuces have higher sugar, phenols and flavonoids content. Lettuce growth under blue dominate LED (LEDb) was delayed, but these plants contain higher chlorophylls content. The differences in plant growth, response to light and biochemical content b etween cultivars wer e detected

Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNFα), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both - experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.publishersversionPeer reviewe

Novel germline MLH1 and MSH2 mutations in latvian Lynch syndrome families

Background/Aims: Hereditary non-polyposis colorectal cancer or Lynch syndrome is an autosomal dominantly inherited disease with high penetrance, mostly due to mutations in the MLH1 and MSH2 genes. The aim of this study is to investigate the mutation spectrum of the MLH1 and MSH2 genes. Methodology: High risk colorectal cancer families were selected from overall 1053 consecutive patients. Screening of germline mutations in the MLH1 and MSH2 was performed by direct sequencing and multiplex ligation-dependent probe amplification. Results: Ten patients fulfilled the Amsterdam I/II criteria and Bethesda guidelines of the Lynch syndrome. Three novel mutations were identified in MLH1 and MSH2 genes, as well as two known mutations in the MLH1 gene. Large rearrangements in the MLH1 gene were found in two patients. Conclusions: The mutations in the MLH1 and MSH2 genes in Latvian high-risk families are highly heterogeneous. Combination of direct sequencing and MLPA is the most appropriate molecular method of detecting hereditary nonpolyposis colorectal cancer patients and family members at risk

Aerosol Jet Printed Organic Memristive Microdevices Based on a Chitosan:PANI Composite Conductive Channel

In this study we show a chitosan:polyaniline (CPA)-based ink, responding to eco-biofriendly criteria, specifically developed for the manufacturing of the first organic memristive device (OMD) with an aerosol jet printed conductive channel. Our contribution is in the context of bioelectronics, where there is an increasing interest in emulating neuro-morphic functions. In this framework, memristive devices and systems have been shown to be well suited. In particular organic-based devices are envisaged as very promising in some applications, such as brain-machine interfacing, owing to specific properties of organics (e.g., biocompatibility, mixed ionic-electronic conduction). On the other hand, the research activities on flexible organic (bio)electronic devices and direct writing (DW) noncontact techniques increasingly overlap in the effort of achieving reliable applications benefiting from the rapid prototyping to accomplish a fast device optimization. In this context, ink-based techniques, such as aerosol jet printing (AJP), although particularly well suited to implement 3D-printed electronics due to advantages it offers in terms of a wide set of allowed printable materials, still require research efforts aimed at conferring printability to the desired precursors. The developed CPA composite was characterized by FTIR, DLS, and MALDI-TOF techniques, while the related aerosol jet printed films were studied by SEM and profilometry. Taking advantage of the intrinsic and stable electrical conductivity of CPA films, which do not necessarily require any acidic treatment to promote a sustained charge carrier conduction, 10 mu m short-channel OMDs were hence manufactured by interfacing the printed CPA layers with a solid polyelectrolyte (SPE). We accordingly demonstrated prototypes of stable and best performing OMD devices with downscaled features, showing well-defined counterclockwise hysteresis/rectification and an enhanced durability. These properties pave the way to further improving performance, as well as to realizing a direct integration of the devices into hardware neural networks by in-line fabrication routes

Impact of KRAS variant rs61764370 on breast cancer morbidity

Low-penetrance gene variants and their combinations are topical study objects in breast cancer pathogenesis. Single nucleotide polymorphism rs61764370, localized in 3՛ UTR of KRAS gene, plays an important role in the development and progression of seve­ral cancers. The aim of our study was to determine the KRAS variant impact on breast cancer morbidity. Patients and Methods: 2214 patients diagnosed with breast cancer and 861 healthy controls were screened for KRAS variant by RFLP method. Available clinical data were collected and processed using statistical analysis methods. Results of present study suggest the KRAS variant impact on breast cancer development risk in premenopausal women, but it has no effect on breast cancer prognosis. We did not observe any KRAS variant effect on breast cancer patient 10-year disease-specific survival rates. Key Words: breast cancer, rs61764370, KRAS variant, predisposing factor

Toxicity and Applications of Internalised Magnetite Nanoparticles Within Live Paramecium caudatum Cells

© 2017, The Author(s). The nanotechnology revolution has allowed us to speculate on the possibility of hybridising nanoscale materials with live substrates, yet significant doubt still remains pertaining to the effects of nanomaterials on biological matter. In this investigation, we cultivate the ciliated protistic pond-dwelling microorganism Paramecium caudatum in the presence of excessive quantities of magnetite nanoparticles in order to deduce potential beneficial applications for this technique, as well as observe any deleterious effects on the organisms’ health. Our findings indicate that this variety of nanoparticle is well-tolerated by P. caudatum cells, who were observed to consume them in quantities exceeding 5–12% of their body volume: cultivation in the presence of magnetite nanoparticles does not alter P. caudatum cell volume, swimming speed, growth rate or peak colony density and cultures may persist in nanoparticle-contaminated media for many weeks. We demonstrate that P. caudatum cells ingest starch-coated magnetite nanoparticles which facilitates their being magnetically immobilised whilst maintaining apparently normal ciliary dynamics, thus demonstrating that nanoparticle biohybridisation is a viable alternative to conventional forms of ciliate quieting. Ingested magnetite nanoparticle deposits appear to aggregate, suggesting that (a) the process of being internalised concentrates and may therefore detoxify (i.e. render less reactive) nanomaterial suspensions in aquatic environments, and (b) P. caudatum is a candidate organism for programmable nanomaterial manipulation and delivery

PREPARATION AND PROPERTIES OF MURINE ANTI-IDIOTYPIC MONOCLONAL ANTIBODIES RECOGNIZING PRIMARY RABBIT POLYCLONAL ANTIBODIES AGAINST MORPHINE DERIVATIVES

Anti-idiotypic antibodies (Ab2), according to the network theory of Jerne, are second-generation immunoglobulins that are produced against the idiotype of an antibody to a specific antigen. Despite the large number of works devoted to the study of the properties of these proteins, their role in the regulation of the immune system is not fully known. It may consist in maintaining or blocking a minimal immune response to the antigen. The study of Ab2 is of great practical and scientific importance. The special properties of Ab2, namely, the ability to partially reproduce the structure of the primary antigen and, upon immunization, induce the appearance of tertiary antibodies, which, like first-generation antibodies, can bind to the antigen, have found application in the development of Ab2-based vaccines, in particular, for the treatment of tumors. In view of the presence of a number of limitations on research related to psychoactive substances, the development of Ab2- based vaccines against drug addiction also seems promising. To example, anti-idiotypic antibodies obtained for this purpose possessing a cocaine-like structure are described in the literature. In this work, murine monoclonal anti-idiotypic antibodies (mAb2) mimicking the structure of various morphine derivatives were obtained. Rabbit polyclonal antibodies to the 6-hemisuccinyl derivative of morphine conjugated with bovine serum albumin isolated by affinity chromatography were used as primary antibodies for immunization. Four hybridoma clones were obtained as a result of the fusion of immunized mice lymphocytes with mouse Sp2/0 mouse myeloma cells by the Milstein-Köhler method. After growth in animals, mAb2 produced by hybridoma cells were affinity purified. We investigated the physicochemical and antigenic properties of the isolated antibodies. It was shown that the obtained mAb2 differ in immunological specificity, competing in different degree with morphine derivatives for binding to first-generation antibodies. We tested the possibility of using the obtained mAb2 as antigen analogues in the solid-phase enzyme-linked immunosorbent assay to determine the titer of primary antibodies against morphine in the blood serum of laboratory animals immunized with morphine derivatives. Based on the obtained anti-idiotypic antibodies, it is proposed to develop test systems to determine the serum opiate-specific antibodies in people after specific vaccination for therapeutic or prophylactic purposes to avoid the use of drugs as antigens immobilized on the solid phase in the analysis

Correction to: Health-related qualify of life, angina type and coronary artery disease in patients with stable chest pain

The original article [1] contained an error in coauthor, Balazs Ruzsics’s name which has since been corrected

Health-related qualify of life, angina type and coronary artery disease in patients with stable chest pain

Background: Health-related quality of life (HRQoL) is impaired in patients with stable angina but patients often present with other forms of chest pain. The aim of this study was to compare the pre-diagnostic HRQoL in patients with suspected coronary artery disease (CAD) according to angina type, gender, and presence of obstructive CAD. Methods: From the pilot study for the European DISCHARGE trial, we analysed data from 24 sites including 1263 patients (45.9% women, 61.1 ± 11.3 years) who were clinically referred for invasive coronary angiography (ICA; 617 patients) or coronary computed tomography angiography (CTA; 646 patients). Prior to the procedures, patients completed HRQoL questionnaires: the Short Form (SF)-12v2, the EuroQoL (EQ-5D-3 L) and the Hospital Anxiety and Depression Scale. Results: Fifty-five percent of ICA and 35% of CTA patients had typical angina, 23 and 33% had atypical angina, 18 and 28% had non-anginal chest discomfort and 5 and 5% had other chest discomfort, respectively. Patients with typical angina had the poorest physical functioning compared to the other angina groups (SF-12 physical component score; 41.2 ± 8.8, 43.3 ± 9.1, 46.2 ± 9.0, 46.4 ± 11.4, respectively, all age and gender-adjusted p < 0.01), and highest anxiety levels (8.3 ± 4.1, 7.5 ± 4.1, 6.5 ± 4.0, 4.7 ± 4.5, respectively, all adjusted p < 0.01). On all other measures, patients with typical or atypical angina had lower HRQoL compared to the two other groups (all adjusted p < 0.05). HRQoL did not differ between patients with and without obstructive CAD while women had worse HRQoL compared with men, irrespective of age and angina type. Conclusions: Prior to a diagnostic procedure for stable chest pain, HRQoL is associated with chest pain characteristics, but not with obstructive CAD, and is significantly lower in women. Trial registration: Clinicaltrials.gov, NCT02400229