Increased Immunoendocrine Cells in Intestinal Mucosa of Postinfectious Irritable Bowel Syndrome Patients 3 Years after Acute Shigella Infection - An Observation in a Small Case Control Study

PURPOSE: Postinfectiously irritable bowel syndrome (PI-IBS) develops in 3-30% of individuals with bacterial gastroenteritis. Recent studies demonstrated increases in inflammatory components in gut mucosa of PI-IBS patients even after complete resolution of infection. We aimed to investigate histological changes in colon and rectum of PI-IBS subjects after long term period of infection. MATERIALS AND METHODS: We recruited PI-IBS subjects who had been diagnosed IBS after complete resolution of enteritis caused by shigellosis outbreak 3 years earlier. We compared unmatched four groups, PI-IBS (n = 4), non PI-IBS (n = 7), D-IBS (n = 7, diarrhea predominant type) and healthy controls (n = 10). All of them underwent colonoscopic biopsy at three areas, including descending colon (DC), sigmoid colon (SC) and rectum, which were assessed for 5-hydroxytryptamine (5-HT)/peptide YY (PYY)-containing enterochromaffin (EC) cell, intraepithelial (IEL) and lamina propria T lymphocyte (CD3), CD8 lymphocytes, mast cells and CD68/calprotectin+ macrophages. RESULTS: All subjects had no structural or gross abnormalities at colonoscopy. In PI-IBS, 5-HT containing EC cells, PYY containing EC cells, IELs, CD3 lymphocytes, CD8 lymphocytes, mast cells, and CD68 + macrophages were increased compared to control (p < 0.05). In D-IBS, PYY containing EC cells, IELs, and CD3 lymphocytes were increased compared to control (p < 0.05). In PI-IBS, 5-HT containing EC cells tended to increase and PYY containing EC cells, CD8 lymphocytes, mast cells, and CD68+ macrophages were increased compared to non PI-IBS (p < 0.05). Calprotectin + marcrophages were decreased in PI-IBS, non PI-IBS and IBS compared to control. CONCLUSION: The immunoendocrine cells were sporadically increased in PI-IBS, non PI-IBS and D-IBS compared with control. Our findings in a very small number of patients suggest that mucosal inflammation may play a role in long-term PI-IBS, and that other sub-groups of IBS and larger scale studies are needed to confirm this observation.ope

Guideline Development for the Evaluation of Visual Impairment in Korea

This guideline is developed to provide criteria for evaluating permanent impairment of the visual system as it affects an individual`s ability to perform activities of daily living. This new assessment system is based on the 5th and 6th edition of American Medical Association and McBride impairment assessment system but revised on the consideration of Korean culture and simple application. This evaluation of impairment is based on an assessment of visual acuity and visual field. Especially it weighs binocular vision and binocular visual fields and the binocular vision and binocular visual fields provide 50% of weight and the right and left eye each contribute 25%. A further adjustment of the impairment rating is included at the final step of this evaluation. Functional deficits for individual adjustments include diplopia, problem of accommodation, abnormality of eyelids, tearing, cosmetic problems from cornea opacity, glare, aphakia, and dark-adaptation. The adjustment can be added to impairment rating up to 15%. Further study is necessary to revise and update of this disability evaluation that have potential problems in actual application.COLEBRANDER A, 2003, DISABILITY EVALUATIO, pCH36FUHR PS, 2003, VISUAL IMPAIR RES, V5, P137COCCHIARELLA L, 2001, GUIDES EVALUATION PECOLENBRANDER A, 2001, DUANES CLIN OPHTHALM, V5, pCH51*INT LOW VIS C INT, 1999, GUID EV VIS IMPCOLENBRANDER A, 1994, LOW VISION RES NEW D, P542DOYLE D, 1993, OXFORD TXB PALLIATIV, P109MCBRIDE DE, 1968, INJURY EYE DISABILIT, P465

Fabrication of Complex 3D Micro-Scale Scaffolds and Drug Delivery Devices using Dynamic Mask Projection Microstereolithography

Microstereolithography (μSL) technology can fabricate three-dimensional (3D) tissue engineered scaffolds with controlled biochemical and mechanical micro-architectures. A μSL system for tissue engineering was developed using a Digital Micromirror Device (DMDTM) for dynamic pattern generation and an ultraviolet (UV) lamp filtered at 365 nm for crosslinking the photoreactive polymer solution. The μSL system was designed with x-y resolution of ~2 μm and a vertical (z) resolution of ~1 μm. To demonstrate the use of μSL in tissue engineering, poly(propylene fumarate) (PPF) was synthesized with a molecular weight of ~1200 Da. The viscosity of the PPF was reduced to ~150 cP (at 50 o C) by mixing with diethyl fumarate (DEF) in the ratio of 7:3 (w/w). Finally, ~2 % (w/w) of (bis(2,4,6- trimethylbenzoyl) phenylphosphine oxide (BAPO) was added to the solution to serve as a photoinitiator. Cure depth experiments were performed to determine the curing characteristics of the synthesized PPF, and the resulting system and photopolymer were used to construct a variety of 3D porous scaffolds with interconnected pores between 100 and 150 μm and a micro-needle array with height of ~800 μm and individual tip diameters of ~20 μm. SEM and microscope images of the micro-architectures illustrate that the developed μSL system is a promising technology for producing biodegradable and biocompatible microstructures.Mechanical Engineerin

Acinetobacter baumannii invades epithelial cells and outer membrane protein A mediates interactions with epithelial cells

<p>Abstract</p> <p>Background</p> <p><it>Acinetobacter baumannii </it>is a nosocomial pathogen of increasing importance, but the pathogenic mechanism of this microorganism has not been fully explored. This study investigated the potential of <it>A. baumannii </it>to invade epithelial cells and determined the role of <it>A. baumannii </it>outer membrane protein A (AbOmpA) in interactions with epithelial cells.</p> <p>Results</p> <p><it>A. baumannii </it>invaded epithelial cells by a zipper-like mechanism, which is associated with microfilament- and microtubule-dependent uptake mechanisms. Internalized bacteria were located in the membrane-bound vacuoles. Pretreatment of recombinant AbOmpA significantly inhibited the adherence to and invasion of <it>A. baumannii </it>in epithelial cells. Cell invasion of isogenic AbOmpA^-mutant significantly decreased as compared with wild-type bacteria. In a murine pneumonia model, wild-type bacteria exhibited a severe lung pathology and induced a high bacterial burden in blood, whereas AbOmpA^-mutant was rarely detected in blood.</p> <p>Conclusion</p> <p><it>A. baumannii </it>adheres to and invades epithelial cells. AbOmpA plays a major role in the interactions with epithelial cells. These findings contribute to the understanding of <it>A. baumannii </it>pathogenesis in the early stage of bacterial infection.</p

Improvement of Mechanical Properties of UV-curable Resin for High-aspect Ratio Microstructures Fabricated in Microstereolithography

Recently, microstructures fabricated using microstereolithography technology have been used in the biological, medical and mechanical fields. Microstereolithography can fabricate real 3D microstructures with fine features, although there is presently a limited number of materials available for use in the process. Deformation of the fine features on a fabricated microstructure remains a critical issue for successful part fabrication, and part deformation can occur during rinsing or during fabrication as a result of fluid flow forces that occur during movement of mechanical parts of the system. Deformation can result in failure to fabricate a particular feature by breaking the feature completely, spatial deflection of the feature, or attaching the feature to neighboring microstructures. To improve mechanical strength of fabricated microstructures, a clay nanocomposite can be used. In particular, a high-aspect ratio microstructure can be fabricated without distortion using photocurable liquid resin containing a clay nanocomposite. In this paper, a clay nanocomposite was blended with a photocurable liquid resin to solve the deformation problem that occurs during fabrication and rinsing. An optimal mixture ratio of a clay nanocomposite was found through tensile testing and the minimal allowable distance between microstructures was found through fabrication experimentation. Finally, using these results, high-aspect ratio microstructures were fabricated using a clay nanocomposite resin without distortion

The Chemical Compositions of Very Metal-Poor Stars HD 122563 and HD 140283; A View From the Infrared

From high resolution (R = 45,000), high signal-to-noise (S/N > 400) spectra gathered with the Immersion Grating Infrared Spectrograph (IGRINS) in the H and K photometric bands, we have derived elemental abundances of two bright, well-known metal-poor halo stars: the red giant HD 122563 and the subgiant HD 140283. Since these stars have metallicities approaching [Fe/H] = -3, their absorption features are generally very weak. Neutral-species lines of Mg, Si, S and Ca are detectable, as well as those of the light odd-Z elements Na and Al. The derived IR-based abundances agree with those obtained from optical-wavelength spectra. For Mg and Si the abundances from the infrared transitions are improvements to those derived from shorter wavelength data. Many useful OH and CO lines can be detected in the IGRINS HD 122563 spectrum, from which derived O and C abundances are consistent to those obtained from the traditional [O I] and CH features. IGRINS high resolutions H- and K-band spectroscopy offers promising ways to determine more reliable abundances for additional metal-poor stars whose optical features are either not detectable, or too weak, or are based on lines with analytical difficulties.Comment: Accepted for publication in ApJ (28 pages, 4 tables, 6 figures

Generation of a single-cycle pulse using a two-stage compressor and its temporal characterization using a tunnelling ionization method

A single-cycle laser pulse was generated using a two-stage compressor and characterized using a pulse characterization technique based on tunnelling ionization. A 25-fs, 800-nm laser pulse was compressed to 5.5 fs using a gas-filled hollow-core fibre and a set of chirped mirrors. The laser pulse was further compressed, down to the single-cycle limit by propagation through multiple fused-silica plates and another set of chirped mirrors. The two-stage compressor mitigates the development of higher-order dispersion during spectral broadening. Thus, a single-cycle pulse was generated by compensating the second-order dispersion using chirped mirrors. The duration of the single-cycle pulse was 2.5 fs, while its transform-limited duration was 2.2 fs. A continuum extreme ultraviolet spectrum was obtained through high-harmonic generation without applying any temporal gating technique. The continuum spectrum was shown to have a strong dependence on the carrier-envelope phase of the laser pulse, confirming the generation of a single-cycle pulse. © 2019, The Author(s