1,269 research outputs found

    A highly sensitive and selective viral protein detection method based on RNA oligonucleotide nanoparticle

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    Globally, approximately 170 million people (representing approximately 3% of the population worldwide), are infected with hepatitis C virus (HCV) and at risk of serious liver disease, including chronic hepatitis. We propose a new quantum dots (QDs)-supported RNA oligonucleotide approach for the specific and sensitive detection of viral protein using a biochip. This method was developed by immobilizing a HCV nonstructural protein 5B (NS5B) on the surface of a glass chip via the formation of a covalent bond between an amine protein group and a ProLinkerā„¢ glass chip. The QDs-supported RNA oligonucleotide was conjugated via an amide formation reaction from coupling of a 5ā€²-end-amine-modified RNA oligonucleotide on the surface of QDs displaying carboxyl groups via standard EDC coupling. The QDs-conjugated RNA oligonucleotide was interacted to immobilized viral protein NS5B on the biochip. The detection is based on the variation of signal of QDs-supported RNA oligonucleotide bound on an immobilized biochip. It was demonstrated that the value of the signal has a linear relationship with concentrations of the HCV NS5B viral protein in the 1 Ī¼g mLāˆ’1 to 1 ng mLāˆ’1 range with a detection limit of 1 ng mLāˆ’1. The major advantages of this RNA-oligonucleotide nanoparticle assay are its good specificity, ease of performance, and ability to perform one-spot monitoring. The proposed method could be used as a general method of HCV detection and is expected to be applicable to other types of diseases as well

    Immune-enhancing screening of fourteen plants on murine macrophage RAW 264.7 cells

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    Purpose: To investigate the potential immune-enhancing effects of fourteen natural plant extracts on mouse macrophage RAW 264.7 cells.Methods: Fourteen plant extracts from 7 different plants were tested on RAW 264.7 cells to determine their immunostimulant activities. Methylthiazolydiphenyltetrazolium bromide (MTT) and Griess assays were performed to evaluate cell viability and nitric oxide (NO) production, respectively. Then, immune related proteins were measured by western blot analysis, while cytokines and phagocytic activity were determined by enzyme-linked immunosorbent assay (ELISA) method.Results: Among the 14 plant extracts, the hot water extract of Agastache rugose was selected based on the screening results on NO production. The hot water extract of A. rugose significantly increased NO production in a concentration-dependent manner without any cytotoxicity. In addition, the expression levels of proteins (iNOS and COX-2) and cytokines (TNF-Ī±, IL-1Ī², IL-6 and IL-12) closely related to immune reaction were also significantly upregulated. Furthermore, phagocytic activity of RAW 264.7 cells significantly increased following treatment with A. rugosa.Conclusion: The hot water extract of A. rugosa exhibits significant immune-stimulant activity. Therefore, A. rugosa can be used as a natural resource for immune enhancement or dietary supplement.Keywords: Immune enhancing activity, Macrophage polarization, Natural plant extracts, Agastache rugosa, RAW 264.

    Anti-amyloidogenic effect of menaquinone-7 on betaamyloid production and aggregation

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    Purpose: To investigate the beneficial effects of menaquinone-7 (MK-7), an isoform of vitamin K2, against beta-amyloid (AĪ²) production and aggregation in Alzheimer's disease using in vitro assays. Methods: The cytotoxicity of MK-7 was determined by MTT assay. The amount of AĪ² produced and secreted into the supernatant by APP-CHO cells treated with MK-7 was evaluated by ELISA. The expression of Ī²-secretases and ADAM10, a representative Ī±-secretase, was determined using western blot analysis. The production of sAPPĪ² and sAPPĪ± fragments generated by Ī²-secretases and Ī±secretase, respectively, were also determined by western blot analysis. The effect on AĪ² aggregation was assessed using Thioflavin T (Th T) assay. Results: MK-7 (up to 75 nM) significantly decreased AĪ² production in APP-CHO cells. This was accompanied by decreased expression of Ī²-secretase and lower production of sAPPĪ² (p < 0.05). However, expression of ADAM10 and production of sAPPĪ± were not significantly affected. In contrast, MK-7 significantly decreased AĪ² aggregation in a dose-dependent manner (p < 0.05). Conclusion: MK-7 exerts anti-amyloidogenic effects via decreased production and lower aggregation of AĪ² into oligomers and fibrils. Therefore, dietary supplementation with MK-7 may be beneficial for the prevention of Alzheimerā€™s disease

    Translation and validation of the Korean confusion assessment method for the intensive care unit

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    <p>Abstract</p> <p>Background</p> <p>Delirium is a common problem and associated with poor outcomes in intensive care unit (ICU) patients. Diagnosis of delirium in ICU patients is limited and usually underdiagnosed by physicians. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is one of the most widely used screening methods for detection of ICU delirium. Our goal was to translate and validate the CAM-ICU for use in the Korean ICU setting.</p> <p>Methods</p> <p>Translation of the CAM-ICU was done according to the guidelines suggested by the Translation and Cultural Adaptation Group. For validation and interrater reliability assessment of the Korean CAM-ICU, two nurses independently assessed delirium in ICU patients and the results were compared with the reference evaluation, which was done by a psychiatrist using the Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV).</p> <p>Results</p> <p>Twenty-two patients were evaluated by two nurses and one psychiatrist expert independently. During the study period, we have continuously educated study nurses. Based on DSM-IV criteria, 16 out of 22 (72.7%) patients developed delirium. The sensitivities of the two nurses' evaluations using the Korean CAM-ICU were 89.80% for nurse 1 and 77.40% for nurse 2. Their specificities were 72.40% and 75.80% and their overall accuracy was 83.33% and 88.37% respectively. The Korean CAM-ICU was done with reasonable interrater reliability between nurse 1 and nurse 2 (Īŗ = 0.81, <it>p </it>< 0.001).</p> <p>Conclusions</p> <p>The Korean CAM-ICU showed good validity and could be incorporated into clinical practice in Korean ICUs.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN50265663">ISRCTN50265663</a></p

    Hypoxia-inducible factor-1 alpha regulates microglial functions affecting neuronal survival in the acute phase of ischemic stroke in mice

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    Cells universally adapt to ischemic conditions by turning on a transcription factor hypoxia-inducible factor (HIF), in which its role is known to differ widely across many different types of cells. Given that microglia have been reported as an essential mediator of neuroinflammation in many brain diseases, we examined the role of HIF in microglia in the progression of an acute phase of ischemic stroke by challenging our novel strains of myeloid-specific Hif-1 alpha or Hif-2 alpha knockout (KO) mice created by Cre-loxP system via middle cerebral artery occlusion (MCAO). We observed that Hif-1 alpha but not Hif-2 alpha KO mice exhibited an improved recovery compared to wild-type (WT) mice determined by behavioral tests. Immunostaining analyses revealed that there were increased numbers of both mature and immature neurons while microglia and apoptotic cells were significantly decreased in the dentate gyrus of Hif-1 alpha KO mice following MCAO. By isolating microglia with fluorescence-activated cell sorter, we found that HIF-1 alpha-deficient microglia were impaired in phagocytosis, reactive oxygen species (ROS) production, and tumor necrosis factor-alpha (TNF-alpha) secretion. We further observed a significant decrease in the expression of Cd36 and milk fat globule-epidermal growth factor 8 (Mfg-e8) genes, both of which contain hypoxia-responsive element (HRE). Knocking down either of these genes in BV2 microglial cells was sufficient to abrogate HIF-mediated increase in phagocytosis, production of intracellular ROS, or TNF-alpha secretion. Our results therefore suggest that HIF-1 alpha in microglia is a novel therapeutic target to protect neuronal survival following an acute phase of ischemic stroke.113Ysciescopu

    Blood and milk metabolites of Holstein dairy cattle for the development of objective indicators of a subacute ruminal acidosis

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    Objective The purpose of this study was to perform a comparative analysis of metabolite levels in serum and milk obtained from cows fed on different concentrate to forage feed ratios. Methods Eight lactating Holstein cows were divided into two groups: a high forage ratio diet (HF; 80% Italian ryegrass and 20% concentrate of daily intake of dry matter) group and a high concentrate diet (HC; 20% Italian ryegrass and 80% concentrate) group. Blood was collected from the jugular vein, and milk was sampled using a milking machine. Metabolite levels in serum and milk were estimated using proton nuclear magnetic resonance and subjected to qualitative and quantitative analyses performed using Chenomx 8.4. For statistical analysis, Studentā€™s t-test and multivariate analysis were performed using Metaboanalyst 4.0. Results In the principal component analysis, a clear distinction between the two groups regarding milk metabolites while serum metabolites were shown in similar. In serum, 95 metabolites were identified, and 13 metabolites (include leucine, lactulose, glucose, betaine, etc.) showed significant differences between the two groups. In milk, 122 metabolites were identified, and 20 metabolites (include urea, carnitine, acetate, butyrate, arabinitol, etc.) showed significant differences. Conclusion Our results show that different concentrate to forage feed ratios impact the metabolite levels in the serum and milk of lactating Holstein cows. A higher number of metabolites in milk, including those associated with milk fat synthesis and the presence of Escherichia coli in the rumen, differed between the two groups compared to that in the serum. The results of this study provide a useful insight into the metabolites associated with different concentrate to forge feed ratios in cows and may aid in the search for potential biomarkers for subacute ruminal acidosis

    Pure Epidural Cavernous Hemangioma of the Cervical Spine that Presented with an Acute Sensory Deficit Caused by Hemorrhage

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    Pure epidural cavernous hemangioma of the spine without vertebral involvement is rare. Due to the slow growth of this lesion, the most common symptoms are chronic pain, myelopathy, and radiculopathy. In our case, the patient complained of an acute onset sensory deficit of the C4 dermatome. An MRI revealed an epidural mass with an acute hematoma. Here, we report a case of a pure epidural cavernous hemangioma that presented with acute neurologic symptoms caused by intralesional hemorrhage and an acute epidural hematoma, which were demonstrated on the patient's MRI

    Transcatheter Closure of Multiple Atrial Septal Defects With the Amplatzer Device

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    Percutaneous device occlusion of secundum atrial septal defect (ASD) has become an accepted alternative to surgical repair. A variety of devices have been used successfully. However, all of them have limitations. We report our experience with two devices used to close multiple ASDs

    Observation of Kondo condensation in a degenerately doped silicon metal

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    When a magnetic moment is embedded in a metal, it captures itinerant electrons to form the Kondo cloud1,2, which can spread out over a few micrometres3,4. For a metal with dense magnetic impurities such that Kondo clouds overlap with each other, correlated ground states are formed. When the impurities form a regular lattice, the result is a heavy fermion or anti-ferromagnetic order depending on the dominant interaction5,6. Even in the case of random impurities, overlapping Kondo clouds are expected to form a coherent ground state. Here, we examine this issue by performing electrical transport and high-precision tunnelling density-of-states (DOS) spectroscopy measurements in a highly P-doped crystalline silicon metal where disorder-induced localized magnetic moments exist7. We detect the Kondo effect in the resistivity of the Si metal below 2 K and an exotic pseudogap in the DOS with gap edge peaks at a Fermi energy below 100 mK. The DOS gap and peaks are tuned by applying an external magnetic field and transformed into a metallic Altshuler-Aronov gap8 in the paramagnetic disordered Fermi liquid (DFL) phase. We interpret this phenomenon as the Kondo condensation, the formation of a correlated ground state of overlapping Kondo clouds, and its transition to a DFL. The boundary between the Kondo condensation and DFL phases is identified by analysing distinct DOS spectra in the magnetic field-temperature plane. A detailed theoretical analysis using a holographic method 9 , 10 , 11 reproduces the unusual DOS spectra, 1, supporting our scenario. Our work demonstrates the observation of the magnetic version of Bardeen-Cooper-Shrieffer (BCS) pair condensation and will be useful for understanding complex Kondo systems.Comment: 34 pages,5+6 figures, accepted in nature physic
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