Recent Increase of Human Granulocytic Anaplasmosis and Co-Infection with Scrub Typhus or Korean Hemorrhagic Fever with Renal Syndrome in Korea.

We report 17 patients with human granulocytic anaplasmosis between January 2015 and September 2018 at two tertiary university hospitals in Korea. Monthly incidence peaked in May and June. Among these patients, we identified three who were co-infected with scrub typhus, and one patient with hemorrhagic fever with renal syndrome.

Surface Plasmon Resonance Aptamer Biosensor for Discriminating Pathogenic Bacteria Vibrio parahaemolyticus.

In this paper, whole-bacteria SELEX (WB-SELEX) strategy was adopted to isolate specific aptamers against Vibrio parahaemolyticus. Round selection for V. parahaemolyticus was conducted 11 rounds, including two negative selection rounds. It was determined through real-time PCR amplification and post-SELEX experiment. The selected aptmers had high binding property and specificity to V. parahaemolyticus. Of 28 aptamers tested, VPCA-apta#1 had the highest binding affinity compared to other aptamer candidates obtained. To detect V. parahaemolyticus, aptamer based SPR biosensor platform was constructed and pathogenic bacteria sensing was conducted in two steps. The first step was to construct 5'-biotinylated VPCA-apta#1 binding probe. The second step was to incubate V. parahaemolyticus and test microbes in functionalized SA sensor chip in parallel. Our platform showed significant activity for detecting and discriminating V. parahaemolyticus from other enteric species such as Escherichia coli, Listeria monocytogenes, Sigella sonnei, and Vibrio fischeri. This is the first report on the use of whole-SELEX to isolate DNA aptamers specific for V. parahaemolyticus. We demonstrated the feasibility of using aptamer platform for the detection of V. parahaemolyticus in various food supplies. It might be used in multiple points of care for diagnosing Vibriosis.

Defining the copper binding aptamotif and aptamer integrated recovery platform (AIRP).

The potential copper binding sites in aptamers have been predicted on the basis of secondary structures and the binding affinity of aptamers with copper. Out of the 4 aptamers (Cu-A1 to Cu-A4) selected by SELEX and examined in the present study, the Cu-A2 aptamer shows the highest binding affinity to copper with the lowest KD value of 1.83 × 10-11 M. In order to confirm the binding of copper to the proposed region, the binding affinity was experimentally validated using mutation and deletion analysis. We have confirmed that the high G-C pairing patterns and short stem-interval distance play important roles in copper binding. Aptamer specificity was also verified against diverse heavy metals. We also demonstrate an Aptamer Integrated Recovery Platform (AIRP) to recover copper from acidic mine drainage. AIRP can be easily regenerated at least 20 times without significant deterioration of the retrieval performance. To the best of our knowledge, AIRP is the first demonstration of copper specific recovery using aptamers. This can be scaled up and would have diverse applications in metal contaminated water treatment, recovery and as a potential biosensor for environmental analysis, monitoring, and risk assessment.

Porcine epidemic diarrhea (PED) infection, diagnosis and vaccination: A mini review.

Porcine epidemic diarrhea virus (PEDV) is a main etiology causing severe enteric disease in piglets with clinical signs of anorexia, vomiting, diarrhea and dehydration resulting in loss of condition and death within a few days. Historically, PED is one of major causes of loss in swine and remains prevalent in some parts of the world. Even with increase in the available tests for PED diagnosis, which include histological diagnosis; virological diagnosis and serological diagnosis, there is no vaccine or specific treatment for this disease yet. In this mini review, the overview and current situation of PED is described with updated techniques, in an effort to comprehensively discuss and understand the disease characteristics.

Aptamer-based Sandwich Assay and its Clinical Outlooks for Detecting Lipocalin-2 in Hepatocellular Carcinoma (HCC).

We validated a single-stranded, DNA aptamer-based, diagnostic method capable of detecting Lipocalin-2 (LCN2), a biomarker from clinically relevant hepatocellular carcinoma (HCC) patient serum, in the sandwich assay format. Nine aptamers (LCN2_apta1 to LCN2_apta9) for LCN2 were screened with SELEX processes, and a sandwich pair (LCN2_apta2 and LCN2_apta4) was finally chosen using surface plasmon resonance (SPR) and dot blotting analysis. The result of the proposed aptamer sandwich construction shows that LCN2 was sensitively detected in the concentration range of 2.5-500 ng mL(-1) with a limit of detection of 0.6 ng mL(-1). Quantitative measurement tests in HCC patients were run on straight serum and were compared with the performance of the conventional antibody-based ELISA kit. The aptamer sandwich assay demonstrated an excellent dynamic range for LCN2 at clinically relevant serum levels, covering sub-nanogram per mL concentrations. The new approach offers a simple and robust method for detecting serum biomarkers that have low and moderate abundance. It consists of functionalization, hybridization and signal read-out, and no dilution is required. The results of the study demonstrate the capability of the aptamer sandwich assay platform for diagnosing HCC and its potential applicability to the point-of-care testing (POCT) system.

Analytical bioconjugates, aptamers, enable specific quantitative detection of Listeria monocytogenes.

As a major human pathogen in the Listeria genus, Listeria monocytogenes causes the bacterial disease listeriosis, which is a serious infection caused by eating food contaminated with the bacteria. We have developed an aptamer-based sandwich assay (ABSA) platform that demonstrates a promising potential for use in pathogen detection using aptamers as analytical bioconjugates. The whole-bacteria SELEX (WB-SELEX) strategy was adopted to generate aptamers with high affinity and specificity against live L. monocytogenes. Of the 35 aptamer candidates tested, LMCA2 and LMCA26 reacted to L. monocytogenes with high binding, and were consequently chosen as sensing probes. The ABSA platform can significantly enhance the sensitivity by employing a very specific aptamer pair for the sandwich complex. The ABSA platform exhibited a linear response over a wide concentration range of L. monocytogenes from 20 to 2×10(6) CFU per mL and was closely correlated with the following relationship: y=9533.3x+1542.3 (R(2)=0.99). Our proposed ABSA platform also provided excellent specificity for the tests to distinguish L. monocytogenes from other Listeria species and other bacterial genera (3 Listeria spp., 4 Salmonella spp., 2 Vibrio spp., 3 Escherichia coli and 3 Shigella spp.). Improvements in the sensitivity and specificity have not only facilitated the reliable detection of L. monocytogenes at extremely low concentrations, but also allowed for the development of a 96-well plate-based routine assay platform for multivalent diagnostics.

Correlation between skin prick test and MAST-immunoblot results in patients with chronic rhinitis.

BACKGROUND AND OBJECTIVES: The most reliable method for confirming the causative allergens of allergic rhinitis is the skin prick test, followed by the multiple allergen simultaneous test (MAST), which reportedly has acceptable sensitivity and specificity. This study was designed to confirm whether a novel MAST-immunoblot assay can reliably diagnose allergic rhinitis. METHODS: A retrospective chart review was conducted of chronic rhinitis patients who visited Yeouido St. Mary's Hospital between January 2010 and June 2011. RESULTS: In total, 193 subjects (111 male, 82 female) were included, with a mean age of 30.08 years (range 6-77). The skin prick test detected 132 subjects as having one or more positive responses to allergens, and MAST detected 105 subjects as having one or more positive response. The sensitivity, specificity, and efficiency of the MAST assay were 63.16%, 65.57%, and 63.92%, respectively. Sensitivity, specificity and efficacy for common allergens were not high enough for MAST to replace skin prick test in detecting causative allergens. When correlation was defined as a difference between the classes of MAST and SPT of less than 2, the correlation rates for Dermatophagoides farina and Dermatophagoides pteronyssinus were 65.80% and 59.07%, respectively. CONCLUSION: The correlation between MAST and the skin prick test is not sufficiently strong to use MAST as a diagnostic test to confirm the causative allergen in allergic rhinitis. Further studies to confirm the reliability of MAST should be conducted.

7-Ketocholesterol upregulates interleukin-6 via mechanisms that are distinct from those of tumor necrosis factor-alpha, in vascular smooth muscle cells.

This study investigated the effects of 7-ketocholesterol on interleukin (IL)-6 expression in vascular smooth muscle cells (VSMC). Among the 7 IL examined, only IL-6 transcript was increased by 7-ketocholesterol treatment in human aorta smooth muscle cells. IL-6 transcripts increased up to 24 h after treatment with 7-ketocholesterol, and this effect was profoundly repressed by treatment with p38 MAPK inhibitors and to a lesser extent JNK inhibitors. 7alpha-Hydroxycholesterol, 27-hydroxycholesterol or cholesterol, however, did not induce IL-6 expression. Mechanisms of IL-6 induction by 7-ketocholesterol were investigated in comparison with tumor necrosis factor (TNF)-alpha. Whereas TNF-alpha activated IL-6 promoter, which was impaired by p38 MAPK inhibitors or by mutation in the NF-kappaB-binding site within the promoter region, 7-ketocholesterol did not affect IL-6 promoter activity. Instead, this oxysterol slowed degradation of IL-6 mRNA and increased the amount of cytoplasmic HuR. 7-ketocholesterol significantly increased the amount of intracellular IL-6 protein in the presence of brefeldin A. 7-Ketocholesterol also enhanced IL-6 release from VSMC. IL-6 release by 7-ketocholesterol, although significant, was not as remarkable as that induced by TNF-alpha. These data suggest that 7-ketocholesterol upregulates IL-6 via mechanisms distinct from TNF-alpha and contributes to the intra- and extracellular IL-6 deposits within the vasculature.

Roles of MAPK and NF-kappaB in interleukin-6 induction by lipopolysaccharide in vascular smooth muscle cells.

Toll-like receptor (TLR)-4 signaling promotes cytokine synthesis in vascular smooth muscle cells (VSMC). However, it is unknown how TLR-4 regulates interleukin-6 (IL-6) in VSMC. Therefore, the present study investigated cellular factors involved in TLR-4-mediated IL-6 in VSMC in terms of MAPK and transcription elements. Exposure of aortic smooth muscle cells to TLR4-specific lipopolysaccharide (LPS) not only enhanced IL-6 release but also induced IL-6 transcript via promoter activation. The promoter activation was attenuated by dominant-negative MKK1 and to a lesser extent by dominant-negative MKK3, but not by dominant-negative MKK4. IL-6 promoter activity was diminished by U0126 or SB202190, but not by SP600125. Co-transfection with dominant negative CCAAT/enhancer binding protein or with IkappaB suppressed LPS-induced promoter activation, whereas the promoter activity was not influenced by dominant negative c-Jun. Mutation in the IL-6 promoter region at the binding site of NF-kappaB or C/EBP impaired promoter activation in response to LPS. Further impairment occurred when both NF-kappaB- and C/EBP-binding sites were mutated. LPS-induced IL-6 promoter activation was also prevented by pretreatment with epigallocatechin 3-gallate, curcumin, and resveratrol. The present study reports that TLR4-agonistic LPS induces IL-6 through transcriptional activation in VSMC and ERK1/2, p38 MAPK, NF-kappaB, and C/EBP play active roles in that process.