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Multiple sclerosis is a chronic inflammatory disease of the central nervous system1. Astrocytes are heterogeneous glial cells that are resident in the central nervous system and participate in the pathogenesis of multiple sclerosis and its model experimental autoimmune encephalomyelitis2,3. However, few unique surface markers are available for the isolation of astrocyte subsets, preventing their analysis and the identification of candidate therapeutic targets; these limitations are further amplified by the rarity of pathogenic astrocytes. Here, to address these challenges, we developed focused interrogation of cells by nucleic acid detection and sequencing (FIND-seq), a high-throughput microfluidic cytometry method that combines encapsulation of cells in droplets, PCR-based detection of target nucleic acids and droplet sorting to enable in-depth transcriptomic analyses of cells of interest at single-cell resolution. We applied FIND-seq to study the regulation of astrocytes characterized by the splicing-driven activation of the transcription factor XBP1, which promotes disease pathology in multiple sclerosis and experimental autoimmune encephalomyelitis4. Using FIND-seq in combination with conditional-knockout mice, in vivo CRISPR-Cas9-driven genetic perturbation studies and bulk and single-cell RNAsequencing analyses of samples frommouse experimental autoimmune encephalomyelitis and humans with multiple sclerosis, we identified a new role for the nuclear receptor NR3C2 and its corepressor NCOR2 in limiting XBP1-driven pathogenic astrocyte responses. In summary, we used FIND-seq to identify a therapeutically targetable mechanism that limits XBP1-driven pathogenic astrocyte responses. FIND-seq enables the investigation of previously inaccessible cells, including rare cell subsets defined by unique gene expression signatures or other nucleic acid markers.

Background Clear cell Renal cell carcinoma (ccRCC) is an immunogenic tumor. B7 family members, such as CTLA-4, PD-1, and PD-L1, are the main components of immune checkpoints that regulate various immune responses. Specifically, B7-H3 regulates T cell-mediated immune responses against cancer. This study aimed to analyze the association between B7-H3 and CTLA-4 expression and the prognostic factors of ccRCC to provide a basis for their potential use as predictive factors and in immunotherapy. Methods Formalin-fixed paraffin-embedded specimens were obtained from 244 ccRCC patients, and B7-H3, CTLA-4, and PD-L1 expressions were evaluated using immunohistochemical staining. Results B7-H3 and CTLA-4 were positive in 73 (29.9%) and 57 (23.4%) of the 244 patients, respectively. B7-H3 expression was significantly associated with PD-L1 expression (P P = 0.842). Kaplan–Meier analysis showed that positive B7-H3 expression was associated with poor progression-free survival (PFS) (P P = 0.457). Multivariate analysis revealed that B7-H3 was correlated with poor PFS (P = 0.031), whereas CTLA-4 was not (P = 0.173). Conclusions To the best of our knowledge, this study is the first to investigate B7-H3 and PD-L1 expression and survival in ccRCC. B7-H3 expression is an independent prognostic factor for ccRCC. Furthermore, multiple immune cell inhibitory targets, such as B7-H3 and PD-L1, can be used for therapeutic tumor regression in a clinical setting.

Genotyping of single nucleotide variants (SNVs) has enabled the assessment of disease-related risk factors and significantly improved the potency of diagnosis and prognosis. Meanwhile, genotyping of SNVs is challenging due to the high sequence similarity between wild-type (WT) and SNV. To increase the discrimination between WT and SNV, probes are modified with nucleic acid analogues such as locked nucleic acid (LNA), or deliberate mismatches are introduced to the probe sequence. However, nucleic acid analogues have limitation in high cost and complexity in their synthesis. And a generalized methodology has not been proposed for determining the position and type of deliberate mismatches at the designated experimental conditions to the best of our knowledge. Herein, we propose a reliable workflow for designing mismatch-introduced probes (MIPs) based on nucleic acid thermodynamic analysis and rejection sampling. The theoretical hybridization state of MIP was calculated using nucleic acid thermodynamics, and the detectability was estimated by rejection sampling that simulates the errors from experimental environments. We fabricated MIPs for SNVs in epidermal growth factor receptor, and experimentally demonstrated optimized detectability. The detectability increased up to 7.19-fold depending on the position and type of mismatch; moreover, the optimized MIP showed higher detectability than the LNA probe. This indicates that the workflow can be broadly applied to the optimization of probe sequence for the detection of various disease-related SNVs.

The current health crisis of corona virus disease 2019 (COVID-19) highlights the urgent need for vaccine systems that can generate potent and protective immune responses. Protein vaccines are safe, but conventional approaches for protein-based vaccines often fail to elicit potent and long-lasting immune responses. Nanoparticle vaccines designed to co-deliver protein antigens and adjuvants can promote their delivery to antigen-presenting cells and improve immunogenicity. However, it remains challenging to develop vaccine nanoparticles that can preserve and present conformational epitopes of protein antigens for induction of neutralizing antibody responses. Here, we have designed a new lipid-based nanoparticle vaccine platform (NVP) that presents viral proteins (HIV-1 and SARS-CoV-2 antigens) in a conformational manner for induction of antigen-specific antibody responses. We show that NVP was readily taken up by dendritic cells (DCs) and promoted DC maturation and antigen presentation. NVP loaded with BG505.SOSIP.664 (SOSIP) or SARS-CoV-2 receptor-binding domain (RBD) was readily recognized by neutralizing antibodies, indicating the conformational display of antigens on the surfaces of NVP. Rabbits immunized with SOSIP-NVP elicited strong neutralizing antibody responses against HIV-1. Furthermore, mice immunized with RBD-NVP induced robust and long-lasting antibody responses against RBD from SARS-CoV-2. These results suggest that NVP is a promising platform technology for vaccination against infectious pathogens., Graphical abstract A nanoparticle vaccine platform that preserves conformational epitopes of protein antigens elicits robust humoral immune responses against HIV-1 and SARS-CoV-2.Unlabelled Image, Highlights • Vaccine nanoparticles effectively deliver antigens to dendritic cells in draining lymph nodes. • Vaccine nanoparticles allow conformational display of viral antigens from HIV-1 or SARS-CoV-2. • Vaccine nanoparticles elicit strong neutralizing antibody responses against HIV-1 in rabbits. • Vaccine nanoparticles induce robust and long-lasting antibody responses against SARS-CoV-2 in mice.

Effective intermolecular interaction is required between probe and target molecules for successful detection of biomarkers. Here, we demonstrate that localization of probes on DNA nanostructures improves detection sensitivity and reaction rate. The structural flexibility of DNA nanostructures enabled frequent intramolecular interactions among the localized probes. The Smoluchowski coagulation method and the coarse-grained molecular dynamic software oxDNA were used for theoretical estimation of inter- and intramolecular behaviors of the DNA nanostructures as well as adequate experiments verifying the improvements in sensitivity with probe localization. Remarkably, the probe-localized DNA nanostructure had an increased sensitivity up to 274 times higher than that of the same probes without localization. We believe this achievement represents a wide applicability as a potential design strategy for robust, reliable, and sensitive biosensors.

We screened, for the first time, plasmid-mediated colistin resistance mcr-3 genes among 636 Escherichia coli isolates collected from swine in South Korea. Whole-genome sequencing showed that the E. coli strain harbored the mcr-3 gene in a p17S-208 plasmid with an IncHI2-ST3 plasmid type and a size of 260,399 base pairs. The deduced amino acid sequences revealed that persistent evolution in the bacterial genome has resulted in mcr gene variants. There is a need for extensive surveillance to prevent the dissemination of colistin resistance mcr genes from animal to human.

Nanoparticles (NPs) of protein-based materials have become one of the most promising candidates for drug carriers in drug-delivery systems because of their in vivo nontoxicity, biodegradability, compatibility with hydrophilic drugs, and adaptability to the human body. Many studies have investigated the fabrication of protein NPs from human serum albumin (HSA) as a new drug carrier. It is important for these NPs to remain in the blood until they reach their therapeutic target to achieve the desired effect; the quicker the clearance of drugs from the body, the shorter is the residence time of drugs in the body, which eventually reduces drug efficacy. Macrophage uptake is a major mechanism for clearance of NPs from the body, so, reducing the degree of macrophage uptake is a major challenge in drug-delivery systems. Original studies of HSA NP uptake by macrophages showed that denatured HSA and HSA NPs synthesized with 80% (v/v) ethanol showed a high degree of macrophage uptake. We found that HSA NPs synthesized with lower ethanol content at pH 7 showed lower macrophage uptake in in vitro macrophage cellular uptake experiments. The effects of the preparation parameters of ethanol concentration, pH, and glutaraldehyde on the macrophage uptake of NPs were thoroughly studied. This newly developed protein NP with lower macrophage uptake has potential application as a drug carrier for many delivery systems.

Nanoparticles are used extensively to detect nucleic acid biomarkers due to their analytical applicability and sensitivity. Systems employing the surface plasmon resonance of gold nanomaterials are overwhelmingly considered to be candidates. The aggregation of gold nanomaterials mediated by the hybridization of target DNA at the interface causes a change in the surface plasmon resonance inherent in gold nanomaterials. Such changes can be measured by spectroscopy or even visualized by the naked eye, enabling effective and positive detection. The optical properties of gold nanoparticles are affected by their shape. The geometric appearance of the nanoparticles also affects their colloidal stability and aggregation behavior. In this study, we examined the effect of the geometric appearance of gold nanomaterials on DNA-mediated aggregation behavior through comparative experiments. Experimental and theoretical methods were used concurrently to derive accurate results and to support the hypotheses. Coarse-grained molecular dynamics simulations were performed with a large-scale atomic/molecular massively parallel simulator to understand the aggregation of nanoparticles with the same surface area and various aspect ratios. As a result, we confirmed that the aggregation sensitivity of nanoparticles was affected by the shape of the contact point with the gold nanomaterials. This study demonstrates that the design of a detection system should be accompanied by an in-depth review of the morphology of the nanoparticle.

Room temperature electron mobility of >100 cm2 V–1 s–1 is achieved for a few-layer MoS2 transistor by use of a polyanionic proton conductor as the top-gate dielectric of the device. The use of a proton conductor that inherently exhibits a cationic transport number close to 1 yields unipolar electron transport in the MoS2 channel. The high mobility value is attributed to the effective formation of an electric double layer by the proton conductor, which facilitates electron injection into the MoS2 channel, and to the effective screening of the charged impurities in the vicinity of the device channel. Through careful temperature-dependent transistor and capacitor measurements, we also confirm quenching of the phonon modes in the proton-conductor-gated MoS2 channel, which should also contribute to the achieved high mobility. These devices are then used to assemble a simple resistive-load inverter logic circuit, which can be switched at high frequencies above 1 kHz.

Iron oxide nanoparticles (NPs) were encapsulated with polyaspartamide-based graft copolymers to bind and track the immune cells as imaging probes. Mono-disperse iron oxide NPs with a mean diameter of 10.7 nm were synthesized by the thermal decomposition method, and their shape and distribution were measured by electrophoretic light scattering and transmission electron microscopy. To enhance their biocompatibility, interfacial and hydrodynamic stability, and fluorescence detection, biodegradable polysuccinimide (PSI) grafted with several functional groups of octadecylamine (C18), ethanolamine (EA), ethylenediamine (EDA), 4-(N-maleimidomethyl) cyclohexane carboxylic acid N-hydroxysuccinimide ester (SMCC), and fluorescein isothiocyanate (FITC) was coated on the iron oxide NPs. The structure of the C18/EA/SMCC/FITC-g-PSI copolymer was confirmed using 1H-NMR and FTIR spectroscopy, and its cell binding ability was investigated by flow cytometry and confocal laser scanning microscopy. The synthesized C18/EA/SMCC/FITC-g-PSI copolymer showed an excellent binding affinity to CD4+ T cells, and was highly biocompatible as the cell viability at the highest polymer concentration of 0.4 mg mL−1 was greater than 85 and 75% after 24 and 48 h, respectively, from MTT assay.

A stem cell tracking system is in high demand for the determination of cell destinations and for the validation of cell therapeutic efficacy in regenerative transplantation. To date, near-infrared (NIR) imaging technology has received considerable attention in cell behavior monitoring, owing to its patient compatibility, easy accessibility and cost effectiveness. Conventionally, in vivo cell tracking has been visualized by direct in-cell staining with NIR, where it may be achieved by complicated genetic engineering. Such genetic amendment techniques have suffered from serious challenges, which can destroy a cell's metabolism and can accidentally incur unexpected carcinoma. Herein we demonstrate a novel cell nano-modulation method for noninvasive stem cell monitoring. It is simply achieved by conjugating stem cells with lipid-supported, NIR-tagged, polymeric nanoparticles. These engineered cells, which are designated as NIR-labeled light-emitting stem cells (LESCs), maintain their biochemical functionality (i.e., differentiation, quantum efficacy, etc.) even after conjugation. LESCs were used for in situ stem cell monitoring at inoculation sites. It is speculated that the LESC technique could provide a new preparative methodology for in vivo cell tracking in advanced diagnostic medicine, where cell behavior is a critical issue.

The magnetic properties of nanoparticles make them ideal for using in various applications, especially in biomedical applications. However, the magnetic force generated by a single nanoparticle is low. Herein, we describe the development of nanocomplexes (size of 100 nm) of many iron oxide nanoparticles (IONPs) encapsulated in poly(lactic- co-glycolic acid) (PLGA) using the simple method of emulsion solvent evaporation. The response of the IONP-encapsulated PLGA nanocomplexes (IPNs) to an external magnetic field could be controlled by modifying the amount of IONPs loaded into each nanocomplex. In a constant size of IPNs, larger loading numbers of IONPs resulted in more rapid responses to a magnetic field. In addition, nanocomplexes were coated with a silica layer to facilitate the addition of fluorescent dyes. This allowed visualization of the responses of the IPNs to an applied magnetic field corresponding to the IONP loading amount. We envision that these versatile, easy-to-fabricate IPNs with controllable magnetism will have important potential applications in diverse fields.

We hereby report the first characterization of mcr-3 gene from healthy animals in South Korea. Out of 636 E. coli isolates, collected between 2014- 2017, nine colistin resistant isolates were screened for the presence of mcr-1 and mcr-3 genes. Nine (1.4%) isolates had shown resistance for colistin and among them three and two isolates were mcr-1 harboring and mcr-3 harboring strains, respectively. All the colistin-resistant isolates were multidrug-resistant. mcr-1 and mcr-3 genes were confirmed to be transferred to a recipient E. coli J53 AZR. Keywords: mcr-3 gene, mcr-1 gene, Colistin resistance, Healthy animals, Transferability

Escherichia (E.) coli is commensal bacteria found in the intestine; however, some pathogenic strains cause diseases in animals and humans. Although E. coli does not typically produce hydrogen sulfide (H2S), H2S-producing strains of E. coli have been identified worldwide. The relationship between virulence and H2S production has not yet been determined. Therefore, characteristics of H2S-producing isolates obtained from swine feces were evaluated including antibiotic resistance patterns, virulence gene expression, and genetic relatedness. Rates of antibiotic resistance of the H2S- producing E. coli varied according to antibiotic. Only the EAST1 gene was detected as a virulence gene in five H2S-producing E. coli strains. Genes conferring H2S production were not transmissible although the sseA gene encoding 3-mercaptopyruvate sulfurtransferase was detected in all H2S-producing E. coli strains. Sequences of the sseA gene motif CGSVTA around Cys238 were also identical in all H2S- producing E. coli strains. Diverse genetic relatedness among the isolates was observed by pulsed-field gel electrophoresis analysis. These results suggested that H2S-producing E. coli strains were not derived from a specific clone and H2S production in E. coli is not associated with virulence genes.

A pseudo-eukaryotic nucleus (PEN) system consisting of a gene-containing DNA hydrogel encapsulated in a liposome is fabricated. Owing to the structural characteristics of gene-containing DNA hydrogel, mRNA transcription efficiency is promoted 2.57-fold. Through the use of PEN as a platform for mRNA delivery to the cytosol, prolonged protein translation is achieved.

A real-time photoacoustic tomography (PAT) system is developed using a linear array probe and phantom images are acquired with a pattern of line structure. Moreover, it is attempted to detect line structures from the acquired images by Hough transform. This effort leads to the measurement of a process of magenta passing through a tube and acquisition of images at a speed of about 2 frame/sec. Besides, it is confirmed that the Hough transform applied on the acquired PAT images has the detection rate of about 50% for delineating a line structure.

The aim of this study was to investigate the prevalence and transferability of resistance in tetracycline-resistant Escherichia coli isolates recovered from beef cattle in South Korea. A total of 155 E. coli isolates were collected from feces in South Korea, and 146 were confirmed to be resistant to tetracycline. The tetracycline resistance gene tet (A) (46.5%) was the most prevalent, followed by tet (B) (45.1%) and tet (C) (5.8%). Strains carrying tet (A) plus tet (B) and tet (B) plus tet (C) were detected in two isolates each. In terms of phylogenetic grouping, 101 (65.2%) isolates were classified as phylogenetic group B1, followed in decreasing order by D (17.4%), A (14.2%), and B2 (3.2%). Ninety-one (62.3%) isolates were determined to be multidrug resistant by the disk diffusion method. MIC testing using the principal tetracyclines, namely, tetracycline, chlortetracycline, oxytetracycline, doxycycline, and minocycline, revealed that isolates carrying tet (B) had higher MIC values than isolates carrying tet (A). Conjugation assays showed that 121 (82.9%) isolates could transfer a tetracycline resistance gene to a recipient via the IncFIB replicon (65.1%). This study suggests that the high prevalence of tetracycline-resistant E. coli isolates in beef cattle is due to the transferability of tetracycline resistance genes between E. coli populations which have survived the selective pressure caused by the use of antimicrobial agents.

A novel and simple method for the fabrication of gold nanoparticle (AuNP) clusters was introduced for use as an efficient near-infrared (NIR) photothermal agent. Cationic surfactants were employed to assemble AuNPs into clusters, during which polyvinylpyrrolidone (PVP) was used to stabilize the AuNP clusters. Through this manner, AuNP clusters with a uniform shape and a narrow size distribution (55.4 ± 5.0 nm by electron microscope) were successfully obtained. A mechanism for the formation of AuNP clusters was studied and proposed. Electrostatic interactions between AuNPs and cationic surfactants, hydrophobic interactions between hydrocarbon chains of cationic surfactants, and repulsive steric interactions of PVP were found to play an important role with regard to the formation mechanism. Photothermal effect in the NIR range of the AuNP clusters was demonstrated; results presented a highly efficient photothermal conversion (with a maximum η of 65%) of the AuNP clusters. The clusters could be easily coated by a silica layer, enabling their biocompatibility and colloidal stability in physiological fluids. The easy-to-fabricate AuNP clusters showed high potential of use as an NIR photothermal agent for cancer therapy.

During the self-assembly of different numbers of oligonucleotides comprising junctional DNA nanostructures, a change in environmental variables (e.g., temperature or salt concentration) has a substantial influence on the final products. Further, distinctive annealing temperatures of oligonucleotides are observed depending on the state of hybridization. Here, we present an evaluation of the annealing characteristics of oligonucleotides for the formation of a simple junctional DNA nanostructure using an annealing curve analysis. This method may be useful for analyzing the formation of complex junctional DNA nanostructures.

DNA hydrogels are promising materials for various fields of research, such as in vitro protein production, drug carrier systems, and cell transplantation. For effective application and further utilization of DNA hydrogels, highly effective methods of nano- and microscale DNA hydrogel fabrication are needed. In this respect, the fundamental advantages of a core-shell structure can provide a simple remedy. An isolated reaction chamber and massive production platform can be provided by a core-shell structure, and lipids are one of the best shell precursor candidates because of their intrinsic biocompatibility and potential for easy modification. Here, we demonstrate a novel core-shell nanostructure made of gene-knitted X-shaped DNA (X-DNA) origami-networked gel core-supported lipid strata. It was simply organized by cross-linking DNA molecules via T4 enzymatic ligation and enclosing them in lipid strata. As a condensed core structure, the DNA gel shows Brownian behavior in a confined area. It has been speculated that they could, in the future, be utilized for in vitro protein synthesis, gene-integration transporters, and even new molecular bottom-up biological machineries.

Therapeutic nanocomplexes have been extensively developed for the effective treatment of aggressive cancers because of their outstanding versatility, easy manipulation, and low cytotoxicity. In this study, we describe the synthesis of a novel bovine serum albumin (BSA)-based nanocomplex harboring both Bcl-2-specific small interfering RNA (siRNA) and gold (Au) nanorods (siRNA and rods encapsulated in BSA; SREB) with the aim of developing a targeted breast cancer therapeutic. The SREB complexes contained 2 × 10(5) siRNA molecules and eight Au nanorods per BSA complex and were successively functionalized with polyethylene glycol (PEG) and anti-ErbB-2 antibodies to facilitate active targeting. The synergetic therapeutic activity originating from the two components effectively induced cell death (∼80% reduction in viability compared with control cells) in target breast cancer cells after a single dose of laser irradiation. Intracellular SREB nanocomplex decomposition by proteolytic enzymes resulted in simultaneous RNA interference and thermal ablation, thus leading to apoptosis in the targeted cancer cells. Moreover, these therapeutic effects were sustained for approximately 72 hours. The intrinsic biocompatibility, multifunctionality, and potent in vitro anticancer properties of these SREB nanocomplexes indicate that they have great therapeutic potential for in vivo targeted cancer therapy, in addition to other areas of nanomedicine.

The rapid dissemination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli has significantly contributed to public health hazard globally. A total of 281 E. coli strains recovered from pigs and chickens between 2009 and 2015 in South Korea were analyzed for ESBL production. ESBL phenotypes were recognized in 14 E. coli isolates; ten and three ESBLproducing isolates carried only blaCTX-M and blaCMY genes, respectively, and one isolate harbored both genes. The predominant CTX-M and CMY types were CTX-M-15 (n = 8) and CMY-2 (n = 3). We also detected ESBL-producing isolates harboring blaCTX-M-65, blaCTX-M-14, blaCMY-6, blaDHA-1, and blaTEM-1 genes. All ESBL-producing isolates showed resistance to the extent of the fourth generation cephalosporins, along with multidrug resistance. CTX-M-15- producing isolates showed higher MIC values than CTX-M-14- and CTX-M-65-producing isolates. The blaCTX-M and blaCMY genes have the potential to be transferable. The spreading of blaCMY and blaCTX-M genes was arbitrated mainly v ia F rep a nd I ncI1 plasmids. Our i solates showed clonal diversity in PFGE analysis. This is the first report of E. coli isolates carrying blaCMY-6 in chicken from South Korea. The emergence of CMY-6 ESBLs in a population of poultry suggests that extensive screening with long-term surveillance is necessary to prevent the dissemination of ESBL from chicken to human.

Several fluorescent or luminescent organisms with biological, chemical, and ecological diversity have been proposed as substitutes for use in new imaging and diagnostic technologies. Inspired by these trends, we designed a synthetic fluorescent light-encoding particulate to serve as a novel and prospective cancer-diagnostic imaging platform. The fluorescence-emitting particulate was used practically for both in vitro and in vivo selective cancer diagnostic imaging.

Classical swine fever (CSF), caused by the CSF virus (CSFV), is a highly contagious disease in pigs. In Korea, vaccination using a live-attenuated strain (LOM strain) has been used to control the disease. However, parenteral vaccination using a live-attenuated strain still faces a number of problems related to storage, cost, injection stress, and differentiation of CSFV infected and vaccinated pigs. Therefore, two kinds of new candidates for oral vaccination have been developed based on the translation of the E2 gene of the SW03 strain, which was isolated from an outbreak of CSF in 2002 in Korea, in transgenic rice calli (TRCs) from Oriza sativa L. cv. Dongjin to express a recombinant E2 protein (rE2-TRCs). The expression of the recombinant E2 protein (rE2) in rE2-TRCs was confirmed using Northern blot, SDS-PAGE, and Western blot analysis. Immune responses to the rE2-TRC in mice and pigs were investigated after oral administration. The administration of rE2-TRCs increased E2-specific antibodies titers and antibody-secreting cells when compared to animals receiving the vector alone (p < 0.05 and p < 0.01). In addition, mice receiving rE2-TRCs had a higher level of CD8+ lymphocytes and Th1 cytokine immune responses to purified rE2 (prE2) in vitro than the controls (p < 0.05 and p < 0.01). Pigs receiving rE2-TRCs also showed an increase in IL-8, CCL2, and the CD8+ subpopulation in response to stimulation with prE2. These results suggest that oral administration of rE2-TRCs can induce E2-specific immune responses.

Since the outbreaks of foot-and-mouth disease (FMD) in South Korea in 2010-2011, a trivalent vaccine has been used as a routine vaccination. Despite the high efficacy of the trivalent vaccine, low antibody formation was reported in the pig industry and there is considerable concern about the ability of the vaccine to protect against the Andong strain responsible for recent outbreaks in South Korea. To overcome these problems, immunostimulators have been widely used to improve vaccine efficacy in South Korea, although without any scientific evidence. Based on the current situation, the aim of this study was to investigate the effects of germanium biotite, a feed supplement used to enhance the immune system, on the immune responses to FMD vaccination through the Andong strain challenge experiment in trivalent vaccinated pigs. Following the challenge, the germanium biotite-fed pigs showed high levels of IL-8 in serum, and increased cellular immune responses to stimulation with the Andong strain antigen compared to nonsupplemented pigs. In addition, higher FMD virus (FMDV) neutralizing antibody titers were detected in the germanium biotite-fed group than in the nonsupplemented group before the challenge. The findings of this study indicate that germanium biotite supplement might enhance immune responses to the FMD vaccine in pigs.

With the advent of deoxyribonucleic acid (DNA) nanotechnology, the Y-shaped DNA nanostructure (Y-DNA) as a basic block was first created. Due to their characteristic selectivity and specificity, Y-DNA-based materials have been utilized in a variety of scientific fields including multiplexed nanobarcoding. Basically, the tripod DNA nanostructure was prepared by simple hybridization of three different single stranded DNA (ssDNA). Before the synthetic process, the optical densities (OD) of the three ssDNAs were measured to accurately estimate the concentration. Through repeated temperature fluctuations, three ssDNAs were hybridized into a Y-shaped block with both a central junction and three blunt ended arms. After the reaction, the ODs of the synthesized DNA products were measured and compared with the theoretical OD values calculated by a MATLAB program (‘matrix laboratory’) with different molar concentrations and volumes to predict the presence of Y-DNA. Simultaneously, the product was analyzed by agarose gel electrophoresis to confirm the YDNA structure. The measured ODs of the solutions with confirmed Y-DNA structures were close to the theoretical maximum OD values. This article provides means to help understand and prepare Y-DNA by performing OD measurements. It is highly expected that this guide will be an excellent starting point for structural DNA nanotechnology.

RNA biomarkers have been recently reported to be associated tightly with the diagnosis and prognosis of many diseases. Particularly, cancers considered to be a serious threat to primates are known to be vastly dominated by genetic networks where RNA plays a key role. RNAs are thus recognized as a major target group that can be used for numerous cancer treatments and it is still required to identify and enumerate them in an effective manner. Here, a new topological transformation-based nanobarcoding technique (TNT) is first reported using fluorescence-DNA barcodes engaged with graphene oxide (GOx ) for effectively discriminating short RNAs such as miRNAs and their single nucleotide polyporphisms in tissue and plasma. Through topological transformation into 3D DNA-RNA polygonal structures, various kinds of microRNAs have been read at the same time and analyzed quantitatively. Also, it positively discerned epidermal growth factor receptor (EGFR) mutations known as single base variations of typical lung cancer specific RNAs. A single variant of 0.785% in target EGFR mutations is explicitly detected. It is speculated that the TNT may be a versatile method for polymerase chain reaction (PCR)-free practical diagnosis of several clinical genetic deviations such as significant biotic RNA and genic fragments and would be a promising alternative to conventional PCR terrains.

Immunostimulatory oligodeoxynucleotides (DNAs) have been widely studied in pharmaceutical and biomedical research fields for applications in cancer immunotherapy and vaccination. Toll-like receptors (TLRs) are critical for the instruction and orchestration of the host immune system composed of innate and adaptive immunity. In particular, TLR9 responds to DNAs with unmethylated deoxycytosine-deoxyguanosine (CpG) motifs, thereby inducing the activation of innate immune cells, such as dendritic cells, and consequently, adaptive immune cells. In this study, we developed two kinds of Y-shaped double-stranded DNA nanostructures (Y-DNAs), including a single unit composed of three DNA strands (YS-DNA) and a ligated multiunit complex formed by crosslinking each YS-DNA (YL-DNA), and investigated whether they have immunostimulatory activity in innate immune cells. YS-DNA and YL-DNA induced the production of immune cytokines such as IL-12 and TNF-α and the expression of costimulatory molecules such as CD80 and CD86 in primary mouse dendritic cells and macrophage cells (RAW264.7 cells). A Coprecipitation study demonstrated that YL-DNA was directly associated with TLR9. The induction of immune cytokines by YS-DNA and YL-DNA was abolished in TLR9-deficient primary mouse dendritic cells. The results demonstrated that Y-DNAs induced the activation of dendritic cells and macrophages mediated by the activation of TLR9, as shown by the expression of immune cytokines and costimulatory molecules. The results suggest that Y-DNA nanostructures provide a beneficial strategy for immunotherapy by modulating the immune system.

Advances in nanotechnology have resulted in the introduction of new materials for therapeutic and diagnostic purposes. In particular, DNA and RNA are viewed as representative and generic nano-blocks because of their physiochemical characteristics of specificity and nanoscopic-level accuracy. In addition, the intrinsic biocompatibility of DNA and RNA and their immune stimulation effects make these molecules ideal candidates for the rational design of novel bio-drug molecules. Recently, we reported novel RNA-DNA hybrid stem-loop structures that target and are endocytosed by LNCaP prostate cancer cells with high specificity. To effectively ligate the DNA and RNA modules in this research, we thoroughly evaluated and optimized several ligation parameters, and observed that we could enhance the ligation efficacy by changing the overhang sequences. A change in sequence information (GCAT) resulted in a 4-fold increase in ligation efficiency in comparison with other ligation factors. To determine the in vitro cellular targeting ability of the nanostructures, RNA-DNA hybrid constructs were complexed with gold nanorods (AuNRs), and the ability of these nanorods to target prostate cancer cells was highest at a 2 : 10 molar ratio of LNCaP cancer-specific looped A10 RNA to stem-DNA. Furthermore, doxorubicin (Dox) as a representative anti-prostate cancer therapeutic was loaded into the DNA-RNA hybrid nanostructures. Our results indicate that RNA-DNA hybrid constructs are effective anti-prostate cancer drug delivery platforms and can be employed for both discovery and delivery.

A stem cell interacts with the neighboring cells in its environment. To maintain a living organism's metabolism, either cell-cell or cell-environment interactions may be significant. Usually, these cells communicate with each other through biological signaling by interactive behaviors of primary proteins or complementary chemicals. The signaling intermediates offer the stem cell's functionality on its metabolism. With the rapid advent of omics technologies, various specific markers by which stem cells cooperate with their surroundings have been discovered and established. In this article, we review several stem cell markers used to communicate with either cancer or immune cells in the human body.

In this study, a novel Graphic User Interface (GUI) software development system is suggested so that it can be applied to diagnose breast cancer with utilizing 3~4.2 GHz microwave radiometric data. The estimated inner and surface temperature values on the patient`s right and left breast in terms of microwave radiometry are visualized in HSV color mapping space and their relevant contour regions and lines are depicted by Marching Square graphic algorithm. Also the database system is implemented in terms of patient and diagnostic module to support the medical decisions concerning the breast cancer diagnosis.

An oral delivery system based on ApxIIA#5-expressed on Saccharomyces cerevisiae was studied for its potential to induce immune responses in mice. Murine bone marrow-derived dendritic cells (DCs) stimulated in vitro with ApxIIA#5-expressed on S. cerevisiae upregulated the expression of maturation and activation markers, leading to production of tumor necrosis factor-α, interleukin (IL)-1β, IL-12p70 and IL-10. Presentation of these activated DCs to cluster of differentiation CD4+ T cells collected from mice that had been orally immunized with the ApxIIA#5-expressed on S. cerevisiae elicited specific T-cell proliferation. In addition, the orally immunized mice had stronger antigen-specific serum IgG and IgA antibody responses and larger numbers of antigen-specific IgG and IgA antibody-secreting cells in their spleens, Peyer's patches and lamina propria than did those immunized with vector-only S. cerevisiae or those not immunized. Furthermore, oral immunization induced T helper 1-type immune responses mediated via increased serum concentrations of IgG2a and an increase predominantly of IFN-γ-producing cells in their spleens and lamina propria. Our findings suggest that surface-displayed ApxIIA#5-expressed on S. cerevisiae may be a promising candidate for an oral vaccine delivery system for eliciting systemic and mucosal immunity.

Underwater wireless communication systems can be useful for underwater environment observation, catastrophe prevention, ocean resources exploration, ocean organism research, vessel sinking exploration, and so on. However, unlike terrestrial wireless communication, underwater wireless communication should consider factors such as long propagation delay, limited transmission capacity, high bit-error rate due to potential loss in power, ambient noise, man-made noise, multi-path, etc., because of the inherent characteristics of water. Thus, in this paper, we propose a suitable media access control(MAC) protocol that applies a combination of the ALOHA MAC protocol and the CSMA/CA MAC protocol to underwater environment. We further propose a mathematical analysis model to evaluate performance. We also verify performance improvement in the proposed scheme in comparison with existing MAC protocols.

The aim of this study was to applicate and evaluate a SYBR Green real-time PCR for the specific detectionof Salmonella spp. Specificity of the PCR method was confirmed with 48 Salmonella spp. and 5 non-Salmonella strainsusing invA gene primer. The average threshold cycle (C T ) of Salmonella spp. was 11.83± 0.78 while non-Salmonellaspp. was 30.86± 1.19. Correlation coefficients of standard curves constructed using C T versus copy number ofSalmonella Enteritidis ATCC 13076 showed good linearity (R 2 = 0.993; slope = 3.563). Minimum level of detectionwith the method was > 10 2 colony forming units (CFU)/mL. These results suggested that the SYBR Green real-timePCR might be applicable for the specific detection of Salmonella spp. isolates.Keywords : invA, Salmonella spp, specific detection, SYBR Green real-time PCR 서론 최근 우리나라에서도 식습관의 서구화로 인해 축산물의 소비가 증가함에 따라 축산물의 안정적인 공급과 안전성에 대한 관심이 갈수록 커지고 있다. 대부분의 선진국에서 식품의안전성과 관련해 가장 연구가 활발히 진행되고 있는 질병 중하나가 살모넬라균증(Salmonellosis)이다 [28].Salmonella 균은 종종 사람에서 식중독과 같은 위장관 질병뿐만 아니라, 장티푸스(typhoid fever)와 같은 급성 전신감염 질환을 유발하는 위험성을 지니고 있다 [8, 22, 24].이러한 Salmonella는 대부분 축산 현장에서 감염된 동물들의도축·가공되는 과정에서 Salmonella 균이 식육 및 축산가공품에 잔재하여 발생한다 [7, 13]. 국내에서 생산되는 다양한 육류 및 축산가공품도 이러한 경로를 통해 오염이 된다.대부분의 Salmonella 혈청형들은 잠재적으로 병원성을 지니고 있어 신속한 검출이 요구되는 바이나, 기존의 세균배양기법은 시간이 오래 걸리고, 분리가 어려울 뿐만 아니라, 혈청형 동정이 매우 까다로운 단점이 있다 [29]. 이러한 이유로 신속한 동정을 위한 많은 연구들이 진행되어 왔다 [11,12, 25]. 이러한 동정 기법들 중 하나가 바로 real-timePCR 기법이다. Real-time PCR 기법은 기존의 conventionalPCR에 비해 높은 민감도와 특이도를 가지며, amplicon의 크기를 줄일 수 있으며, PCR 이후의 과정이 필요 없어 PCRproduct의 오염을 방지할 수 있다 [15, 27].TaqMan 탐침 기반의 real-time PCR을 이용한 Salmonella균 검출기법들이 여러 차례 소개되었다 [4, 9, 16, 19, 23,27]. 그러나 이들 검출 기법은 primer와 형광탐침 간의 결합력에 크게 영향을 받는 등 실험조건이 까다로워 쉽게 적용하지 못하는 단점이 있었다 [21]. SYBR Green의 사용은이러한 한계를 극복하여 형광탐침을 사용하지 않고도 real-time PCR이 가능하게 되었다 [1].최근 SYBR Green real-time PCR을 이용한 많은 연구들

This study investigated 247 Escherichia coli isolates collected from four cattle farms to characterize aminoglycoside-modifying enzyme (AME) genes, their plasmid replicons and transferability. Out of 247 isolates a high number of isolates (total 202; 81.78%) were found to be resistant to various antibiotics by disc diffusion. Of the 247 strains, 139 (56.3%) were resistant to streptomycin, and other antibiotic resistances followed as tetracycline (12.15%), ampicillin (7%), chloramphenicol (5.7%) and trimethoprim-sulfamethoxazole (0.8%). Among 247 isolates B1 was the predominant phylogenetic group identified comprising 151 isolates (61.1%), followed by groups A (27.9%), D (7%) and B2 (4%). Out of 139 isolates investigated for AME, 130 (93.5%) isolates carried at least one AME gene. aph3″-1a and aph3″-1b (46%) were the principal genes detected, followed by aac3-IVa (34.5%). ant2″-1a was the least detected gene (2.2%). Nine (6.5%) strains carried no AME genes. Twelve (63.2%) among 19 isolates transferred an AME gene to a recipient and aph3΄-1a was the dominant transferred gene. Transferability mainly occurred via the IncFIB replicon type (52.6%). Pulsed-field gel electrophoresis typing demonstrated a higher degree of diversity with 14 distinct cluster types. This result suggests that commensal microflora from food-producing animals has a tremendous ability to harbor and transfer AME genes, and poses a potential risk by dissemination of resistance to humans through the food chain.

In this study, the novel digital filtering algorithms are implemented to suppress the noisy characteristics embedded in ambulatory electrocardiogram signals by an android smartphone platform. With this aim, Graphical User Interface (GUI) is designed and implemented by utilizing multithread-Java programming to realize Finite Impulse Response and Infinite Impulse Response filter. With simulating our implemented digital filters built in an android smartphone, we can find the fact that we can efficiently suppresses the noisy characteristics due to baseline wandering and 60 Hz powerline source fluctuations especially in electrocardiograms.

In this study, ambulatory electrocardiogram(ECG) signal and the rhythms of heart beats are visualized in terms of R-R intervals and Heart Rate Variability(HRV) in the environment of an android plaform. With this aim, Graphical User Interface(GUI) is implemented by executing multi-thread Java programming modules including ECG, heart-beats, tachogram and visualization unit. ECG signals are acquired in an android device by receiving the data from ambulatory ECG sensory system. Finite Impulse Response(FIR) filters are implemented to eliminate the baseline wandering noises contained in the ambulatory signals and DC-offset level in R-R interval data. With simulating the normal or stress emotional state of a subject, we can find the fact that HRV can be successfully estimated and visualized in an android smart phone platform.

It is quite important to improve the visual acuity of a medical image by suppressing noisy parts and simultaneously keeping the details of signal components to draw the accurate diagnostics. With this aim, we suggest a novel method to generate Rotational Kernel Transformation (RKT) filter mask with applying Bresenham`s algorithm and implement an nonlinear filtering algorithm to eliminate noises. As a result, we can find the fact that RKT filter mask can be automatically created and the visual acuity of a corrupted image can be elevated in terms of the signal-to-noise ratio (SNR) with applying the RKT filter.

Germanium biotite, a natural mineral, has been used as a feed supplement to reinforce innate immune ability. The aim of the present study was to evaluate the effects of germanium biotite on the adsorptive and inhibition of growth abilities against Escherichia (E.) coli and Salmonella spp. in vitro. Two strains of enterotoxigenic E. coli and four strains of two Salmonella serotypes (Salmonella Derby and Salmonella Typhimurium), major bacterial diarrheal pathogens, were used for this experiment. The absorptive ability of germanium biotite against most Salmonella used in present experiment was observed weakly. The germanium biotite, however, showed significant effect of bacterial growth inhibition in most experiment bacteria. These results suggest that the use of the germanium biotite as feed supplement could alleviate diarrhea following inhibition of bacteria growth. It is also presumed that antibiotics usage for farm animals, considered as causes of antibiotic residue in meat and emerging antibiotic resistance, could be reduced through the use of germanium biotite as a feed supplement, in place of antibiotics used for the prevention of diarrhea.

Underwater wireless network can be useful in various fields such as underwater environment observation, catastrophe prevention, ocean resources exploration, ocean organism research, and vessel sinking exploration. We need to develop an efficient design for Medium Access Control (MAC) protocol to improve multiple data communication in underwater environment. Aloha protocol is one of the basic and simple protocols, but it has disadvantage such as collision occurs oftenly in communication. If there is collision occured in RF communication, problem can be solved by re-sending the data, but using low frequency in underwater, the re-transmission has difficulties due to slow bit-rate. So, Time Division Multiple Access (TDMA) based MAC protocol is going to be used to avoid collisions, but if there is no data to send in existing TDMA, time slot should not be used. Therefore, this paper proposes dynamic TDMA protocol mechanism with reducing the time slots by sending short “I Have No Data” (IHND) message, if there is no data to transmit. Also, this paper presents mathematic analysis model in relation to data throughput, channel efficiency and verifies performance superiority by comparing the existing TDMA protocols.

Brucella abortus is a facultative intracellular bacteria that replicates within a macrophage without producing any classical virulence factors. It can become internalized to cells by zipper-like and/or swimming internalization mechanisms. However, the bacterial proteins involved in internalization remain unclear. To define these bacterial proteins, random insertion mutants of B. abortus were generated by the Tn5 transposome complexes. In all, 132 mutants were screened, cellular internalization-defective mutants were selected, and these genomic and envelope proteomic features were identified. The transposon insertion sites were ccmC,ppk and BruAb2_0168 for the mutant C10, C29 and D7, respectively. Mutant C10 showed a deficiency in internalization without any changes in expression of the cell envelope proteins; however, mutant C29 showed a reduced expression of OMP25, and a mutant D7 also showed reduced expression of OMP25, OMP28 and Porin2b. These results suggest OMP25 is not an essential factor, but might be involved in host cellular internalization. We identified the ppk gene and BruAb2_0168 locus which are associated to expression of OMP25, OMP28 and Porin2b as well as pleiotropic effects of ccmC gene.