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Cisplatin is an effective drug for treating various cancer types. However, it is highly toxic for both healthy and tumor cells. Therefore, there is a need to reduce its therapeutic dose and increase targeted bioavailability. One of the ways to achieve this could be the coating of cisplatin with polysaccharides and specific carriers for targeted delivery. Nucleic acid aptamers could be used as carriers for the specific delivery of medicine to cancer cells. Cisplatin-arabinogalactan-aptamer (Cis-AG-Ap) conjugate was synthesized based on Cis-dichlorodiammineplatinum, Siberian larch arabinogalactan, and aptamer AS-42 specific to heat-shock proteins (HSP) 71 kDa (Hspa8) and HSP 90-beta (Hsp90ab1). The antitumor effect was estimated using ascites and metastatic Ehrlich tumor models. Cis-AG-Ap toxicity was assessed by blood biochemistry on healthy mice. Here, we demonstrated enhanced anticancer activity of Cis-AG-Ap and its specific accumulation in tumor foci. It was shown that targeted delivery allowed a 15-fold reduction in the therapeutic dose of cisplatin and its toxicity. Cis-AG-Ap sufficiently suppressed the growth of Ehrlich's ascites carcinoma, the mass and extent of tumor metastasis

Aptamer selection against novel infections is a complicated and time-consuming approach. Synergy can be achieved by using computational methods together with experimental procedures. This study aims to develop a reliable methodology for a rational aptamer in silico et vitro design. The new approach combines multiple steps: (1) Molecular design, based on screening in a DNA aptamer library and directed mutagenesis to fit the protein tertiary structure; (2) 3D molecular modeling of the target; (3) Molecular docking of an aptamer with the protein; (4) Molecular dynamics (MD) simulations of the complexes; (5) Quantum-mechanical (QM) evaluation of the interactions between aptamer and target with further analysis; (6) Experimental verification at each cycle for structure and binding affinity by using small-angle X-ray scattering, cytometry, and fluorescence polarization. By using a new iterative design procedure, structure- and interaction-based drug design (SIBDD), a highly specific aptamer to the receptor-binding domain of the SARS-CoV-2 spike protein, was developed and validated. The SIBDD approach enhances speed of the high-affinity aptamers development from scratch, using a target protein structure. The method could be used to improve existing aptamers for stronger binding. This approach brings to an advanced level the development of novel affinity probes, functional nucleic acids. It offers a blueprint for the straightforward design of targeting molecules for new pathogen agents and emerging variants.

Cisplatin is an effective anticancer drug used to treat various types of cancer. The main disadvantage of the drug is its high toxicity. To reduce the toxic effect of cisplatin, we conjugated it with arabinogalactan, which is capable of forming soluble globules and bind poorly soluble pharmacological compounds by confining them inside spheroid globules. In this study, we compared the biological effect and mechanism of action of cisplatin and its complex with arabinogalactan (AG–Pt) on the growth of Ehrlich ascites carcinoma in vivo. It has been shown that the conjugates of arabinogalactan with cisplatin exerted a strong antitumor effect despite the fact that the dose of cisplatin in the composition of the conjugates was 10 times less than the standard dose. At the same time, the conjugates of arabinogalactan with cisplatin were virtually nontoxic. It has been established that the antitumor effect of cisplatin and its conjugates with arabinogalactan is due to the induction of apoptosis in tumor cells. It is assumed that a decrease in toxicity and an increase in the efficacy of cisplatin-arabinogalactan conjugates compared to pure cisplatin are associated with its more efficient accumulation in tumor cells.

Nucleic acid (NA) aptamers bind to their targets with high affinity and selectivity. The three-dimensional (3D) structures of aptamers play a major role in these non-covalent interactions. Here, we use a four-step approach to determine a true 3D structure of aptamers in solution using small-angle X-ray scattering (SAXS) and molecular structure restoration (MSR). The approach consists of (i) acquiring SAXS experimental data of an aptamer in solution, (ii) building a spatial distribution of the molecule's electron density using SAXS results, (iii) constructing a 3D model of the aptamer from its nucleotide primary sequence and secondary structure, and (iv) comparing and refining the modeled 3D structures with the experimental SAXS model. In the proof-of-principle we analyzed the 3D structure of RE31 aptamer to thrombin in a native free state at different temperatures and validated it by circular dichroism (CD). The resulting 3D structure of RE31 has the most energetically favorable conformation and the same elements such as a B-form duplex, non-complementary region, and two G-quartets which were previously reported by X-ray diffraction (XRD) from a single crystal. More broadly, this study demonstrates the complementary approach for constructing and adjusting the 3D structures of aptamers, DNAzymes, and ribozymes in solution, and could supply new opportunities for developing functional nucleic acids. Graphical abstract.

Two high-affinity DNA aptamers for lung tumor cells were applied as biospecific elements in bioluminescent assay of patient blood. The oligonucleotide complementary to the 5′ end of both aptamers carrying either biotin or Ca2+-regulated photoprotein obelin was used to form a sandwich-type analytical complex on the surfaces of magnetic streptavidin-activated microspherical particles. Clinical blood samples from cases of morphologically confirmed lung cancer and control samples were analyzed applying the developed assay. From the receiver operator curve (ROC) analysis, the chosen threshold value as clinical decision limit offers the sensitivity of 91.5% and the specificity of 75% (p

Magnetomechanical therapy is one of the most perspective directions in tumor microsurgery. According to the analysis of recent publications, it can be concluded that a nanoscalpel could become an instrument sufficient for cancer microsurgery. It should possess the following properties: (1) nano- or microsized; (2) affinity and specificity to the targets on tumor cells; (3) remote control. This nano- or microscalpel should include at least two components: (1) a physical nanostructure (particle, disc, plates) with the ability to transform the magnetic moment to mechanical torque; (2) a ligand—a molecule (antibody, aptamer, etc.) allowing the scalpel precisely target tumor cells. Literature analysis revealed that the most suitable nanoscalpel structures are anisotropic, magnetic micro- or nanodiscs with high-saturation magnetization and the absence of remanence, facilitating scalpel remote control via the magnetic field. Additionally, anisotropy enhances the transmigration of the discs to the tumor. To date, four types of magnetic microdiscs have been used for tumor destruction: synthetic antiferromagnetic P-SAF (perpendicular) and SAF (in-plane), vortex Py, and three-layer non-magnetic–ferromagnet–non-magnetic systems with flat quasi-dipole magnetic structures. In the current review, we discuss the biological effects of magnetic discs, the mechanisms of action, and the toxicity in alternating or rotating magnetic fields in vitro and in vivo. Based on the experimental data presented in the literature, we conclude that the targeted and remotely controlled magnetic field nanoscalpel is an effective and safe instrument for cancer therapy or theranostics.

The clinical course of chronic lymphocytic leukemia (CLL) is very ambiguous, showing either an indolent nature of the disease or having latent dangerous progression, which, if diagnosed, will require an urgent therapy. The prognosis of the course of the disease and the estimation of the time of therapy initiation are crucial for the selection of a successful treatment strategy. A reliable estimating index is needed to assign newly diagnosed CLL patients to the prognostic groups. In this work, we evaluated the comparative expressions of proteins in CLL blood cells using a label-free quantification by mass spectrometry and calculated the integrated proteomic indexes for a group of patients who received therapy after the blood sampling over different periods of time. Using a two-factor linear regression analysis based on these data, we propose a new pipeline for evaluating model development for estimation of the moment of therapy initiation for newly diagnosed CLL patients.

Diabetic nephropathy, hypertension, and glomerulonephritis are the most common causes of chronic kidney diseases (CKD). Since CKD of various origins may not become apparent until kidney function is significantly impaired, a differential diagnosis and an appropriate treatment are needed at the very early stages. Conventional biomarkers may not have sufficient separation capabilities, while a full-proteomic approach may be used for these purposes. In the current study, several machine learning algorithms were examined for the differential diagnosis of CKD of three origins. The tested dataset was based on whole proteomic data obtained after the mass spectrometric analysis of plasma and urine samples of 34 CKD patients and the use of label-free quantification approach. The k-nearest-neighbors algorithm showed the possibility of separation of a healthy group from renal patients in general by proteomics data of plasma with high confidence (97.8%). This algorithm has also be proven to be the best of the three tested for distinguishing the groups of patients with diabetic nephropathy and glomerulonephritis according to proteomics data of plasma (96.3% of correct decisions). The group of hypertensive nephropathy could not be reliably separated according to plasma data, whereas analysis of entire proteomics data of urine did not allow differentiating the three diseases. Nevertheless, the group of hypertensive nephropathy was reliably separated from all other renal patients using the k-nearest-neighbors classifier &ldquo, one against all&rdquo, with 100% of accuracy by urine proteome data. The tested algorithms show good abilities to differentiate the various groups across proteomic data sets, which may help to avoid invasive intervention for the verification of the glomerulonephritis subtypes, as well as to differentiate hypertensive and diabetic nephropathy in the early stages based not on individual biomarkers, but on the whole proteomic composition of urine and blood.

Novel nanoscale bioconjugates combining unique plasmonic photothermal properties of gold nanoparticles (AuNPs) with targeted delivery using cell-specific DNA aptamers have a tremendous potential for medical diagnostics and therapy of many cell-based diseases. In this study, we demonstrate the high anti-cancer activity of aptamer-conjugated, 37-nm spherical gold nanoparticles toward Ehrlich carcinoma in tumor-bearing mice after photothermal treatment. The synthetic anti-tumor aptamers bring the nanoparticles precisely to the desired cells and selectively eliminate cancer cells after the subsequent laser treatment. To prove tumor eradication, we used positron emission tomography (PET) utilizing radioactive glucose and computer tomography, followed by histological analysis of cancer tissue. Three injections of aptamer-conjugated AuNPs and 5 min of laser irradiations are enough to make the tumor undetectable by PET. Histological analysis proves PET results and shows lower damage of healthy tissue in addition to a higher treatment efficiency and selectivity of the gold nanoparticles functionalized with aptamers in comparison to control experiments using free unconjugated nanoparticles.

Magnetomechanical cell disruption using nano- and microsized structures is a promising biomedical technology used for noninvasive elimination of diseased cells. It applies alternating magnetic field (AMF) for ferromagnetic microdisks making them oscillate and causing cell membrane disruption with cell death followed by apoptosis. In this study, we functionalized the magnetic microdisks with cell-binding DNA aptamers and guided the microdisks to recognize cancerous cells in a mouse tumor in vivo. Only 10 min of the treatment with a 100 Hz AMF was enough to eliminate cancer cells from a malignant tumor. Our results demonstrate a good perspective of using aptamer-modified magnetic microdisks for noninvasive microsurgery for tumors.

Nanotechnologies involving physical methods of tumor destruction using functional oligonucleotides are promising for targeted cancer therapy. Our study presents magnetodynamic therapy for selective elimination of tumor cells in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low frequency alternating magnetic field. We developed an enhanced targeting approach of cancer cells with aptamers and arabinogalactan. Aptamers to fibronectin (AS-14) and heat shock cognate 71 kDa protein (AS-42) facilitated the delivery of the nanoparticles to Ehrlich carcinoma cells, and arabinogalactan (AG) promoted internalization through asialoglycoprotein receptors. Specific delivery of the aptamer-modified FeAG nanoparticles to the tumor site was confirmed by magnetic resonance imaging (MRI). After the following treatment with a low frequency alternating magnetic field, AS-FeAG caused cancer cell death in vitro and tumor reduction in vivo. Histological analyses showed mechanical disruption of tumor tissues, total necrosis, cell lysis, and disruption of the extracellular matrix. The enhanced targeted magnetic theranostics with the aptamer conjugated superparamagnetic ferroarabinogalactans opens up a new venue for making biocompatible contrasting agents for MRI imaging and performing non-invasive anti-cancer therapies with a deep penetrated magnetic field.

Epilepsy is the fourth most prevalent brain disorder affecting millions of people of all ages. Epilepsy is divided into six categories different in etiology and molecular mechanisms; however, their common denominator is the inability to maintain ionic homeostasis. Antiepileptic drugs have a broad spectrum of action and high toxicity to the whole organism. In many cases, they could not penetrate the blood-brain barrier (BBB) and reach corresponding targets. Nucleic acid aptamers are a new and promising class of antiepileptic drugs as they are non-toxic, specific, and able to regulate the permeability of ion channels or inhibit inflammatory proteins. In this review, we summarize the mechanisms of epileptogenesis and its interconnection with the BBB and show the potential of aptamers for antiepileptic treatment.

We selected DNA aptamers to the epithelial cell adhesion molecule (EpCAM) expressed on primary lung cancer cells isolated from the tumors of patients with non-small cell lung cancer using competitive displacement of aptamers from EpCAM by a corresponding antibody. The resulting aptamers clones showed good nanomolar affinity to EpCAM-positive lung cancer cells. Confocal microscopy imaging and spectral profiling of lung cancer tissues confirmed the same protein target for the aptamers and anti-EpCAM antibodies. Furthermore, the resulted aptamers were successfully applied for isolation and detection of circulating tumor cells in clinical samples of peripheral blood of lung cancer patients.

Nucleic acid aptamers are becoming popular as molecular probes for identification and imaging pathology and, at the same time, as a convenient platform for targeted therapy. Recent studies have shown that aptamers may be effectively used for tumor characterization and as commercially available monoclonal antibodies. Here we present three DNA aptamers binding to whole transformed lung cancer tissues, including tumor cells, connective tissues, and blood vessels. Protein targets have been revealed using affinity purification followed by mass spectrometry analyses, and they have been validated using a panel of correspondent antibodies and 3D imaging of tumor tissues. Each of the proteins targeted by the aptamers is involved in cancer progression and most of them are crucial for lung adenocarcinoma. We propose the use of these aptamers in aptahistochemistry for the characterization of the histological structure of lung adenocarcinoma. The value of the presented aptamers is their application together or separately for indicating the spread of neoplastic transformation, for complex differential diagnostics, and for targeted therapy of the tumor itself as well as all transformed structures of the adjacent tissues. Moreover, it has been demonstrated that these aptamers could be used for intraoperative tumor visualization and margin assessment., Graphical Abstract

Lung cancer is a malignant lung tumor with various histological variants that arise from different cell types, such as bronchial epithelium, bronchioles, alveoli, or bronchial mucous glands. The clinical course and treatment efficacy of lung cancer depends on the histological variant of the tumor. Therefore, accurate identification of the histological type of cancer and respective protein biomarkers is crucial for adequate therapy. Due to the great diversity in the molecular-biological features of lung cancer histological types, detection is impossible without knowledge of the nature and origin of malignant cells, which release certain protein biomarkers into the bloodstream. To date, different panels of biomarkers are used for screening. Unfortunately, a uniform serum biomarker composition capable of distinguishing lung cancer types is yet to be discovered. As such, histological analyses of tumor biopsies and immunohistochemistry are the most frequently used methods for establishing correct diagnoses. Here, we discuss the recent advances in conventional and prospective aptamer based strategies for biomarker discovery. Aptamers like artificial antibodies can serve as molecular recognition elements for isolation detection and search of novel tumor-associated markers. Here we will describe how these small synthetic single stranded oligonucleotides can be used for lung cancer biomarker discovery and utilized for accurate diagnosis and targeted therapy. Furthermore, we describe the most frequently used in-clinic and novel lung cancer biomarkers, which suggest to have the ability of differentiating between histological types of lung cancer and defining metastasis rate.

Cancer diagnostics and treatment monitoring rely on sensing and counting of rare cells such as cancer circulating tumor cells (CTCs) in blood. Many analytical techniques have been developed to reliably detect and quantify CTCs using unique physical shape and size of tumor cells and/or distinctive patterns of cell surface biomarkers. Main problems of CTC bioanalysis are in the small number of cells that are present in the circulation and heterogeneity of CTCs. In this chapter, we describe recent progress towards the selection and application of synthetic DNA or RNA aptamers to capture and detect CTCs in blood. Antibody-based approaches for cell isolation and purification are limited because of an antibody's negative effect on cell viability and purity. Aptamers transform cell isolation technology, because they bind and release cells on-demand. The unique feature of anti-CTC aptamers is that the aptamers are selected for cell surface biomarkers in their native state, and conformation without previous knowledge of their biomarkers. Once aptamers are produced, they can be used to identify CTC biomarkers using mass spectrometry. The biomarkers and corresponding aptamers can be exploited to improve cancer diagnostics and therapies .

Current advances in targeted magnetic nanotheranostics are summarized in this review. Unique structural, optical, electronic and thermal properties of magnetic materials in nanometer scale are attractive in the field of biomedicine. Magnetic nanoparticles functionalized with therapeutic molecules, ligands for targeted delivery, fluorescent and other chemical agents can be used for cancer diagnostic and therapeutic purposes. High selectivity, small size, and low immunogenicity of synthetic nucleic acid aptamers make them attractive delivery agents for therapeutic purposes. Properties, production and functionalization of magnetic nanoparticles and aptamers as ligands for targeted delivery are discussed herein. In recent years, magnetic nanoparticles have been widely used in diagnostic methods, such as scintigraphy, single photon emission computed tomography (SPECT), positron emission tomography (PET), magnetic resonance imaging (MRI), and Raman spectroscopy. Therapeutic purposes of magnetic nanoconstructions are also promising. They are used for effective drug delivery, magnetic mediated hypertermia, and megnetodynamic triggering of apoptosis. Thus, magnetic nanotheranostics opens a new venue for complex differential diagnostics, and therapy of metastatic cancer.

New prospects for the applications of single-stranded DNA and RNA as therapeutic agents have been discovered in the recent years. Aptamers are the oligonucleotides that bind to their targets with high affinity and specificity due to the well-defined tertiary structures and spatial charge distribution. Aptamers can be selected for any molecules, virus particles, bacteria, cells, and tissues. They have a wide range of applications from target identification to drug delivery. Aptamers themselves can affect various cell functions by affecting certain proteins and receptors. Here, we present the technique for selecting aptamers with antitumor activity in cancer cell cultures and identifying their target proteins by mass spectrometry analysis. The evolved aptamers showed the following antitumor properties: AS-14 (Kd = 3.8 nM) induced apoptosis (phosphatidylserine translocation determined with Annexin V Alexa Fluor 488) and AS-9 (Kd = 0.75 nM) stopped proliferation (as determined with CellTrace™ Far Red DDAO-SE) in the culture of Ehrlich ascites adenocarcinoma cells. Using high performance liquid chromatography and high resolution tandem mass spectrometry, we have identified the proteins affected by the AS-14 and AS-9 aptamers. One of the most likely targets for AS-14 was filamin A, which is involved in metastasis formation, tumor development, and cell proliferation. According to mass spectrometry data, the AS-9 aptamer influences the α-subunit of mitochondrial ATP synthase, the key component of mitochondrial oxidative phosphorylation, stimulation of which leads to tumor growth suppression. Thus, mass spectrometry data confirmed the results of the experiments on cell cultures showing that the aptamer binding to specific protein targets causes apoptosis and stops proliferation of cancer cells. However, the mechanisms of action of aptamers in vitro and in vivo are not clear enough and still need to be determined. Our study opens up new possibilities for creation of non-toxic drugs based on DNA aptamers for targeted anticancer therapy.

Salmonella is one of the most dangerous and common food-borne pathogens. The overuse of antibiotics for disease prevention has led to the development of multidrug resistant Salmonella. Now, more than ever, there is a need for new antimicrobial drugs to combat these resistant bacteria. Aptamers have grown in popularity since their discovery, and their properties make them attractive candidates for therapeutic use. In this work, we describe the selection of highly specific DNA aptamers to S. enteritidis and S. typhimurium. To evolve species-specific aptamers, twelve rounds of selection to live S. enteritidis and S. typhimurium were performed, alternating with a negative selection against a mixture of related pathogens. Studies have shown that synthetic pools combined from individual aptamers have the capacity to inhibit growth of S. enteritidis and S. typhimurium in bacterial cultures; this was the result of a decrease in their membrane potential.

Cancer diagnostics and treatment monitoring rely on sensing and counting of rare cells such as cancer circulating tumor cells (CTCs) in blood. Many analytical techniques have been developed to reliably detect and quantify CTCs using unique physical shape and size of tumor cells and/or distinctive patterns of cell surface biomarkers. Main problems of CTC bioanalysis are in the small number of cells that are present in the circulation and heterogeneity of CTCs. In this chapter, we describe recent progress towards the selection and application of synthetic DNA or RNA aptamers to capture and detect CTCs in blood. Antibody-based approaches for cell isolation and purification are limited because of an antibody's negative effect on cell viability and purity. Aptamers transform cell isolation technology, because they bind and release cells on-demand. The unique feature of anti-CTC aptamers is that the aptamers are selected for cell surface biomarkers in their native state, and conformation without previous knowledge of their biomarkers. Once aptamers are produced, they can be used to identify CTC biomarkers using mass spectrometry. The biomarkers and corresponding aptamers can be exploited to improve cancer diagnostics and therapies .

The development of an aptamer-based electrochemical sensor for lung cancer detection is presented in this work. A highly specific DNA-aptamer, LC-18, selected to postoperative lung cancer tissues was immobilized onto a gold microelectrode and electrochemical measurements were performed in a solution containing the redox marker ferrocyanide/ferricyanide. The aptamer protein targets were harvested from blood plasma of lung cancer patients by using streptavidin paramagnetic beads and square wave voltammetry of the samples was performed at various concentrations. In order to enhance the sensitivity of the aptasensor, silica-coated iron oxide magnetic beads grafted with hydrophobic C8 and C4 alkyl groups were used in a sandwich detection approach. Addition of hydrophobic beads increased the detection limit by 100 times. The detection limit of the LC-18 aptasensor was enhanced by the beads to 0.023 ng/mL. The formation of the aptamer – protein – bead sandwich on the electrode surface was visualized by electron microcopy. As a result, the electrochemical aptasensor was able to detect cancer-related targets in crude blood plasma of lung cancer patients.

The influence of hypokinesia on the content of free Ca2+ and the level of NAD(P)H in myocytes of rat skeletal muscles and myocardium, and microviscosity of myocyte membranes was investigated. It has been found that hypokinesia increased the free Ca2+ content and NAD(P)H level in myocytes of skeletal muscles and myocardium. Alterations of structural-functional properties of membrane that appeared as an increase of membrane fluidity in the regions of lipid bilayer and protein-lipid contact were observed only in skeletal muscles. It was supposed that an increase of calcium cation level in myocytes stimulated the activity of enzymes involved in the apoptosis process that results in the decrease of muscle tissue mass.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. Here we describe a method of forming large arrays (up to 109 pieces) of free magnetic Ni nano disks 50 nm thick coated on both sides with layers of 5 nm thick Au. The antitumor effect of the magnetic nickel gold coated nanodisks and DNA aptamer conjugates was evaluated in vivo and in vitro. Under the influ ence of rotating magnetic field, the studied nanodisks can cause the death of Ehrlich ascites carcinoma cells.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. The article presents the results of investigation of antitumor properties of platinum–arabinogalactan complex. We showed the ability of the complex to inhibit the growth of Ehrlich ascites tumor cells. It is found that the distribution of the platinum–arabinogalactan complex is not specific only for tumor cells in mice. The complex was found in all tissues and organs examined (ascites cells, embryonic cells, kidney, and liver). The mechanism of action of the arabinogalactan–platinum complex may be similar to cisplatin as the complex is able to accumulate in tumor cells.

Betulin and its esters are the natural compounds with high in vitro cytotoxicity toward many cancer cells. However, the poor water solubility of these compounds has limited their applications. We prepared new composites of betulin esters using two methods, namely ball-milling of the mixtures of betulin esters with arabinogalactan and preparation of thin films of these mixtures by evaporating the aqueous solutions. These composites revealed higher water solubility as compared with the initial substances without losing the structural integrity and functionality. As a result, the new composites have shown much higher inhibitory effects against different cancer cell lines such as Ehrlich ascites carcinoma cells and lung carcinoma cells (A549) in comparison with the initial substances. The cell viability studies based on Annexin V and Propidium iodide probes have confirmed the high proapoptotic effect of betulin ester derivatives against cancer cells.

Circulating tumor cells (CTCs) are rare cells and valuable clinical markers of prognosis of metastasis formation and prediction of patient survival. Most CTC analyses are based on the antibody-based detection of a few epithelial markers; therefore miss an important portion of mesenchymal cancer cells circulating in blood. In this work, we selected and identified DNA aptamers as specific affinity probes that bind to lung adenocarcinoma cells derived from postoperative tissues. The unique feature of our selection strategy is that aptamers are produced for lung cancer cell biomarkers in their native state and conformation without previous knowledge of the biomarkers. The aptamers did not bind to normal lung cells and lymphocytes, and had very low affinity to A549 lung adenocarcinoma culture. We applied these aptamers to detect CTCs, apoptotic bodies, and microemboli in clinical samples of peripheral blood of lung cancer and metastatic lung cancer patients. We identified aptamer-associated protein biomarkers for lung cancer such as vimentin, annexin A2, annexin A5, histone 2B, neutrophil defensin, and clusterin. Tumor-specific aptamers can be produced for individual patients and synthesized many times during anticancer therapy, thereby opening up the possibility of personalized diagnostics.

The development of an aptamer-based viability impedimetric sensor for bacteria (AptaVISens-B) is presented. Highly specific DNA aptamers to live Salmonella typhimurium were selected via the cell-systematic evolution of ligands by exponential enrichment (SELEX) technique. Twelve rounds of selection were performed; each comprises a positive selection step against viable S. typhimurium and a negative selection step against heat killed S. typhimurium and a mixture of related pathogens, including Salmonella enteritidis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Citrobacter freundii to ensure the species specificity of the selected aptamers. The DNA sequence showing the highest binding affinity to the bacteria was further integrated into an impedimetric sensor via self-assembly onto a gold nanoparticle-modified screen-printed carbon electrode (GNP-SPCE). Remarkably, this aptasensor is highly selective and can successfully detect S. typhimurium down to 600 CFU mL(-1) (equivalent to 18 live cells in 30 μL of assay volume) and distinguish it from other Salmonella species, including S. enteritidis and S. choleraesuis. This report is envisaged to open a new venue for the aptamer-based viability sensing of a variety of microorganisms, particularly viable but nonculturable (VBNC) bacteria, using a rapid, economic, and label-free electrochemical platform.

The effects of cisplatin on [Ca 2+ ] in , pH in , NAD(P)H level, and lymphocyte membrane microviscosity were studied in mice with Ehrlich ascitic carcinoma. The level of free [Ca 2+ ] in in lymphocytes from mice with Ehrlich ascitic carcinoma was 4-fold reduced compared to that in intact animals on day 13 of tumor development, while [H + ] in level was elevated. Cisplatin caused no changes in the level of free Ca2+, but reduced cytosol acidification. Lymphocyte membrane fluidity in mice with tumors was increased in the lipid bilayer and in the proteinlipid contact zone and did not depend on cisplatin treatment. The level of NAD(P)H was low in mice with tumors, but increased sharply after cisplatin treatment. It seems that functional activity of lymphocytes decreased at the stage of well-developed tumor, which promoted inhibition of the lymphocyte defense properties. Cisplatin did not modify the structure and functions of lymphocytes and presumably even improved their energy status.

The development of an aptamer-based impedimetric sensor for typing of bacteria (AIST-B) is presented. Highly specific DNA aptamers to Salmonella enteritidis were selected via Cell-SELEX technique. Twelve rounds of selection were performed; each comprises a positive selection step against S. enteritidis and a negative selection step against a mixture of related pathogens, including Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Citrobacter freundii to ensure the species-specificity of the selected aptamers. After sequencing of the pool showing the highest binding affinity to S. enteritidis, a DNA aptamer sequence of high affinity to the bacteria was integrated into an impedimetric sensor via self-assembly onto a gold nanoparticles-modified screen-printed carbon electrode (GNPs-SPCE). Remarkably, this aptasensor is highly selective and can successfully detect S. enteritidis down to 600 CFU 1/mL (equivalent to 18 CFU in 30 \muL assay volume) in 10 minutes and distinguish it from other salmonella species, including S. typhimurium and S. choleraesuis. This report is envisaged to open a new venue for the aptamer-based typing of a variety of microorganisms using a rapid, economic, label-free electrochemical platform., Comment: This paper has been withdrawn by the author due to errors

The content of primary and secondary products of membrane peroxidation, total cholesterol concentration, and relative microviscosity of erythrocyte membranes were measured in women with endometrial cancer and uterine leiomyoma. The content of conjugated dienes in erythrocytes was highest in female patients with malignant tumors of the endometrium. The relative microviscosity of erythrocyte membranes in patients with uterine leiomyoma and endometrial cancer was elevated in the zone of lipid--lipid and protein--lipid contacts.

The changes in free cytoplasmic calcium concentration ([Ca2+](in)) and the effects of extracellular ATP on [Ca2+](in) have been studied in Ehrlich ascites carcinoma cells in the dynamics of their growth. The basal level of [Ca2+](in) and the effects of ATP on the ascites cells were determined by the stage of tumor growth and depended on the content of reactive oxygen species (ROS). The sharp increase in basal and ATP-induced elevation of [Ca2+](in) levels were observed at the 12th day of ascites cell growth. Inhibition of ROS formation by N-acetyl-L-cysteine decreased [Ca2+](in) and suppressed the cell reaction to ATP. We suggest that the increased sensitivity of the ascites cells to ATP observed on the 12th day may be also attributed to a decrease in ecto-ATPase activity.

We studied the adaptive response of rats to cold exposure. It was found that the development of the adaptive response and formation of systemic structural trace in the kidneys occurred within 1 month after the start of adaptation. Activation of proliferative processes in the kidneys was accompanied by an increase in intracellular calcium concentration.