59 research outputs found
Grace S. Fong, Herself an Author : Gender, Agency, and Writing in Late Imperial China, 2008
No full textZufferey Nicolas. Grace S. Fong, Herself an Author : Gender, Agency, and Writing in Late Imperial China, 2008. In: Études chinoises, n°28, 2009. Numéro spécial sur le droit chinois. pp. 243-247
Production of interferon-gamma by activated T-cell receptor-alphabeta CD8alphabeta intestinal intraepithelial lymphocytes is required and sufficient for disruption of the intestinal barrier integrity
No full textMaintenance of intestinal epithelial barrier function is of vital importance in preventing uncontrolled influx of antigens and the potentially ensuing inflammatory disorders. Intestinal intraepithelial lymphocytes (IEL) are in intimate contact with epithelial cells and may critically regulate the epithelial barrier integrity. While a preserving impact has been ascribed to the T-cell receptor (TCR)-gammadelta subset of IEL, IEL have also been shown to attenuate the barrier function. The present study sought to clarify the effects of IEL by specifically investigating the influence of the TCR-alphabeta CD8alphabeta and TCR-alphabeta CD8alphaalpha subsets of IEL on the intestinal epithelial barrier integrity. To this end, an in vitro coculture system of the murine intestinal crypt-derived cell-line mIC(cl2) and syngeneic ex vivo isolated IEL was employed. Epithelial integrity was assessed by analysis of transepithelial resistance (TER) and paracellular flux of fluorescein isothiocyanate-conjugated (FITC-) dextran. The TCR-alphabeta CD8alphaalpha IEL and resting TCR-alphabeta CD8alphabeta IEL did not affect TER of mIC(cl2) or flux of FITC-dextran. In contrast, activated TCR-alphabeta CD8alphabeta IEL clearly disrupted the integrity of the mIC(cl2) monolayer. No disrupting effect was seen with activated TCR-alphabeta CD8alphabeta IEL from interferon-gamma knockout mice. These findings demonstrate that secretion of interferon-gamma by activated TCR-alphabeta CD8alphabeta IEL is strictly required and also sufficient for disrupting the intestinal epithelial barrier function
Macrophages induce neutrophil apoptosis through membrane TNF, a process amplified by Leishmania major
No full textNeutrophils are recruited to the site of parasite inoculation within a few hours of infection with the protozoan parasite Leishmania major. In C57BL/6 mice, which are resistant to infection, neutrophils are cleared from the site of s.c. infection within 3 days, whereas they persist for at least 10 days in susceptible BALB/c mice. In the present study, we investigated the role of macrophages (MPhi) in regulating neutrophil number. Inflammatory cells were recruited by i.p. injection of either 2% starch or L. major promastigotes. Neutrophils were isolated and cultured in the presence of increasing numbers of MPhi. Extent of neutrophil apoptosis positively correlated with the number of MPhi added. This process was strictly dependent on TNF because MPhi from TNF-deficient mice failed to induce neutrophil apoptosis. Assays using MPhi derived from membrane TNF knock-in mice or cultures in Transwell chambers revealed that contact with MPhi was necessary to induce neutrophil apoptosis, a process requiring expression of membrane TNF. L. major was shown to exacerbate MPhi-induced apoptosis of neutrophils, but BALB/c MPhi were not as potent as C57BL/6 MPhi in this induction. Our results emphasize the importance of MPhi-induced neutrophil apoptosis, and membrane TNF in the early control of inflammation
Mycobacteria-specific cytokine responses detect tuberculosis infection and distinguish latent from active tuberculosis
Get PDFRATIONALE: Current immunodiagnostic tests for tuberculosis (TB), including the tuberculin skin test and IFN-? release assay (IGRA), have significant limitations, which include their inability to distinguish between latent TB infection (LTBI) and active TB, a distinction critical for clinical management.OBJECTIVES: To identify mycobacteria-specific cytokine biomarkers that characterize TB infection, determine their diagnostic performance characteristics, and establish whether these biomarkers can distinguish between LTBI and active TB.METHODS: A total of 149 children investigated for TB infection were recruited; all participants underwent a tuberculin skin test and QuantiFERON-TB Gold assay. In parallel, whole-blood assays using early secretory antigenic target-6, culture filtrate protein-10, and PPD as stimulatory antigens were undertaken, and cytokine responses were determined by xMAP multiplex assays.MEASUREMENTS AND MAIN RESULTS: IFN-?, interferon-inducible protein-10 (IP-10), tumor necrosis factor (TNF)-?, IL-1ra, IL-2, IL-13, and MIP-1? (macrophage inflammatory protein-1?) responses were significantly higher in LTBI and active TB cases than in TB-uninfected individuals, irrespective of the stimulant. Receiver operating characteristic analyses showed that IP-10, TNF-?, and IL-2 responses achieved high sensitivity and specificity for the distinction between TB-uninfected and TB-infected individuals. TNF-?, IL-1ra, and IL-10 responses had the greatest ability to distinguish between LTBI and active TB cases; the combinations of TNF-?/IL-1ra and TNF-?/IL-10 achieved correct classification of 95.5% and 100% of cases, respectively.CONCLUSIONS: We identified several mycobacteria-specific cytokine biomarkers with the potential to be exploited for immunodiagnosis. Incorporation of these biomarkers into future immunodiagnostic assays for TB could result in substantial gains in sensitivity and allow the distinction between LTBI and active TB based on a blood test alone
Quantitative isolation of mouse and human intestinal intraepithelial lymphocytes by elutriation centrifugation
No full textIntestinal intraepithelial lymphocytes (IEL) are specialized subsets of T cells with distinct functional capacities. While some IEL subsets are circulating, others such as CD8alphaalpha TCRalphabeta IEL are believed to represent non-circulating resident T cell subsets [Sim, G.K., Intraepithelial lymphocytes and the immune system. Adv. Immunol., 1995. 58: 297-343.]. Current methods to obtain enriched preparations of intraepithelial lymphocytes are mostly based on Percoll density gradient or magnetic bead-based technologies [Lundqvist, C., et al., Isolation of functionally active intraepithelial lymphocytes and enterocytes from human small and large intestine. J. Immunol. Methods, 1992. 152(2): 253-263.]. However, these techniques are hampered by a generally low yield of isolated cells, and potential artifacts due to the interference of the isolation procedure with subsequent functional assays, in particular, when antibodies against cell surface markers are required. Here we describe a new method for obtaining relatively pure populations of intestinal IEL (55-75%) at a high yield (>85%) by elutriation centrifugation. This technique is equally suited for the isolation and enrichment of intraepithelial lymphocytes of both mouse and human origin. Time requirements for fractionating cell suspensions by elutriation centrifugation are comparable to Percoll-, or MACS-based isolation procedures. Hence, the substantially higher yield and the consistent robust enrichment for intraepithelial lymphocytes, together with the gentle treatment of the cells during elutriation that does not interfere with subsequent functional assays, are important aspects that are in favor of using this elegant technology to obtain unmanipulated, unbiased populations of intestinal intraepithelial lymphocytes, and, if desired, also of pure epithelial cells
Mycobacteria-specific mono- And polyfunctional CD4+ T cell profiles in children with latent and active tuberculosis: A prospective proof-of-concept study
Get PDFBackground: Current immune-based TB tests, including the tuberculin skin test (TST) and interferon-gamma release assays (IGRA), have significant limitations, including the inability to distinguish between latent TB infection (LTBI) and active TB. Few biomarkers with the potential to discriminate between these two infection states have been identified. Objective: To determine whether functional profiling of mycobacteria-specific T cells can distinguish between TB-infected and -uninfected children, and simultaneously discriminate between LTBI and active TB. Methods: One hundred and forty-nine children with suspected active TB or risk factors for LTBI were recruited at the Royal Children's Hospital Melbourne. Whole-blood stimulation assays, using ESAT-6, CFP-10, PPD, and heat-killed M. tuberculosis as stimulants, were done, followed by intracellular cytokine staining and flow cytometric analysis. Results: Eighty-two participants in the well-defined diagnostic categories 'uninfected individuals' (asymptomatic, TST 0 mm / IGRA-; n = 61), LTBI (asymptomatic, TST ≥10 mm / IGRA+, normal chest radiograph; n = 15), or active TB [microbiologically-confirmed (n = 3) or fulfilling stringent criteria (n = 3)] were included in the final analysis. The proportions of mycobacteria-specific single-positive TNF-α+ and double-positive IFN-γ+/TNF-α+ CD4+ T cells were significantly higher in participants with active TB than in those with LTBI and uninfected individuals. Additionally, the frequency of IL-17-expressing CD4+ T cells, predominately with single-positive IL-17+ and double-positive IL-2+/IL-17+ phenotypes, was higher in participants with active TB than in the other two groups. Conclusions: The frequencies and functional profiles of mycobacteria-specific CD4+ T cells differ significantly both between TB-infected and TB-uninfected children, and between LTBI and active TB. Although confirmation in further studies will be required, these findings indicate that functional profiling of mycobacteria-specific CD4+ T cells could potentially be exploited for novel immune-based TB assays that enable the distinction between infection states based on a blood sample alone
[Compte rendu de :] Herself an Author: Gender, Agency, and Writing in Late Imperial China / Grace S. Fong
No full textOn the brevity of fantastic narratives.
Get PDFResumen: ¿Por qué podemos definir el relato fantástico como breve? La demostración parte de la idea de que un evento fantástico se expresa mediante una estructura concesiva (del tipo, aunque X, Y). El procedimiento consiste en asociar a un dato comprobable que sirve como cuadro referencial (X) un elemento insólito (Y). La unidad del relato se radica en el esquema concesivo –que define la coherencia narrativa– según el principio de brevedad que realiza (articulación casi-lógica de dos términos). La estructura concesiva constituye entonces el núcleo en que la poética del género debe basarse para crear el texto. Cada autor maneja, a su modo, la construcción concesiva en el relato y, por consiguiente, toma posición en relación con el principio de brevedad.Abstract: How is the fantastic narrative brief? The demonstration starts from the idea that it is by means of the concession (of the type although X, Y) that a fantastic event is expressed: the procedure consists of positing an attested fact which serves as a referential framework (X) and attaching an unusual element (Y) to it. The concessive pattern, since it defines the narrative coherence, founds the unity of the narrative according to the principle of brevity that it achieves (quasi-logical articulation of two terms). The concession thus constitutes the structural core with which the poetics of the genre is destined to play: each author manages, in his or her own way, the concessive formula in the narrative and, as a result, takes a position relative to the principle of brevity.Résumé: En quoi le récit fantastique est-il bref? La démonstration part de l’idée que c'est au moyen de la concession (de type bien que X, Y) que s'exprime un événement fantastique: le procédé consiste à poser une donnée attestée qui sert de cadre référentiel (X) et à lui joindre un élément insolite (Y). Le schème concessif, dès lors qu’il définit la cohérence narrative, fonde l'unité du récit selon le principe de brièveté qu'il réalise (articulation quasi-logique de deux termes). La concession constitue ainsi le noyau structurel avec lequel est vouée à composer la poétique du genre: chaque auteur gère, à sa manière, la formule concessive dans le récit et, de ce fait, prend position relativement au principe de brièveté
Totally laparoscopic treatment of vaginal cuff dehiscence: A case report and systematic literature review
No full textAbstractIntroductionTo highlight the laparoscopic management as a feasible treatment option for vaginal cuff dehiscence with intestinal evisceration after hysterectomy.Presentation of caseWe report a rare case of a 49-year-old postmenopausal woman who was admitted to the emergency department with vaginal herniation of approximately 40cm of small bowel 3 months after total laparoscopic hysterectomy, treated laparoscopically exclusively.DiscussionThe patient underwent a laparoscopic reduction of the protruded mass, inspection of the entire small bowel and closure of the vaginal dehiscence. She was discharged home in a good health and the postoperative course remains uneventful 6 months later.Our systematic review of the literature found 116 cases of vaginal evisceration, which were described as early as 1864. There is no consensus on the ideal method of surgical repair. To our knowledge, only 2% (3 cases) were treated totally laparoscopically and 10% by a combined approach (laparoscopic and vaginal). Although the current evidence does not suggest that one approach is preferred to the others, the laparoscopic approach seems to be the new trend for the management of this surgical emergency.ConclusionTotally laparoscopic repair in experience hands seems to be a safe approach to cure vaginal evisceration after pelvic surgery
Implementing a verified File Transfer Protocol client and server
No full textThesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 54-56).I present my implementation of an FTP: File Transfer Protocol system with GRASShopper. GRASShopper is a program verifier that ensures that programs are memory safe. I wrote an FTP client and server in SPL, the GRASShopper programming language. SPL integrates the program logic's pre- and post- conditions, along with loop invariants, into the language, so that programs that compile in GRASShopper are proven correct. Because of that, my client and server are guaranteed to be secure and correct. I am supervised by Professor Martin Rinard and Dr. Damien Zufferey, a post-doctoral researcher in Professor Rinard's laboratory.by Jennifer Ramseyer.M. Eng
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