445 research outputs found

    Umbilical Metastasis as the Manifestation of an Asymptomatic Gallbladder Carcinoma

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    Sister Mary Joseph's nodule (SMJN) is an eponym used to describe the metastatic lesion of the umbilicus. Umbilical metastases are rare and its occurrence as a first manifestation of an asymptomatic primary malignancy is very rare. The gallbladder is the source of SMJN in 2%-3% of cases. SMJN can present in any one of the following ways; first manifestation of an occult primary malignancy, an indication of recurrence in a patient with a previous malignancy, or as progression of an underlying symptomatic primary disease. Our study emphasizes the importance of identifying this very useful and easily applicable clinical sign by careful physical examination of the abdomen, and also the need for proper clinical evaluation of any umbilical lesion, and the histological diagnosis. In the present study we report on a case of Sister Mary Joseph's Nodule as the presentation of an asymptomatic gallbladder carcinoma, and review the relevant literature

    The complex TIE between macrophages and angiogenesis

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    Macrophages are primarily known as phagocytic immune cells, but they also play a role in diverse processes, such as morphogenesis, homeostasis and regeneration. In this review, we discuss the influence of macrophages on angiogenesis, the process of new blood vessel formation from the pre-existing vasculature. Macrophages play crucial roles at each step of the angiogenic cascade, starting from new blood vessel sprouting to the remodelling of the vascular plexus and vessel maturation. Macrophages form promising targets for both pro- and anti-angiogenic treatments. However, to target macrophages, we will first need to understand the mechanisms that control the functional plasticity of macrophages during each of the steps of the angiogenic cascade. Here, we review recent insights in this topic. Special attention will be given to the TIE2-expressing macrophage (TEM), which is a subtype of highly angiogenic macrophages that is able to influence angiogenesis via the angiopoietin-TIE pathway

    Interleukin-17D and Nrf2 mediate initial innate immune cell recruitment and restrict MCMV infection.

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    Innate immune cells quickly infiltrate the site of pathogen entry and not only stave off infection but also initiate antigen presentation and promote adaptive immunity. The recruitment of innate leukocytes has been well studied in the context of extracellular bacterial and fungal infection but less during viral infections. We have recently shown that the understudied cytokine Interleukin (IL)-17D can mediate neutrophil, natural killer (NK) cell and monocyte infiltration in sterile inflammation and cancer. Herein, we show that early immune cell accumulation at the peritoneal site of infection by mouse cytomegalovirus (MCMV) is mediated by IL-17D. Mice deficient in IL-17D or the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), an inducer of IL-17D, featured an early decreased number of innate immune cells at the point of viral entry and were more susceptible to MCMV infection. Interestingly, we were able to artificially induce innate leukocyte infiltration by applying the Nrf2 activator tert-butylhydroquinone (tBHQ), which rendered mice less susceptible to MCMV infection. Our results implicate the Nrf2/IL-17D axis as a sensor of viral infection and suggest therapeutic benefit in boosting this pathway to promote innate antiviral responses

    Modelling of yield point phenomenon in bake-hardening grade steel

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    In this study the yield point phenomenon in Bake-Hardening grade steel is predicted using a physically based thermo-mechanical model. A modified Taylor equation is proposed with a physically based dislocation density evolution approach. The softening that follows the higher yield point is incorporated with a Voce type decaying exponential function. The strain rate dependency of the plastic hardening is also incorporated in the model. The yield point in the decay function is also strain rate dependent but does not follow the same dependency of plastic hardening. This was solved by making the decay function strain rate dependent by adding a modified strain rate stress term to the exponential function. This parameter is calculated based on tensile experiments. Due to the softening behavior of the material, the numerical model is mesh size sensitive. Hence, a lower order strain gradient enhanced approach is implemented. The gradient is in a form of an additional hardening term assigned in the locally strained bands based on the plastic strain gradient. Hill48 yield criterion is used to assimilate the anisotropy in the steel grade. The numerical results show good correspondence with experimental tensile tests. The regularization significantly reduced the mesh size dependency of the numerical results.</p

    Is magnetic resonance imaging a viable alternative to ultrasound as the primary imaging modality in the diagnosis of paediatric appendicitis? A systematic review

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    YesBackground: Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention in paediatric patients. Ultrasound is generally the diagnostic imaging modality of choice, followed by CT, where paediatric appendicitis is suspected. However, high operator dependency and diagnostic restrictions related to anatomical and clinical presentation may limit consistency of application. This paper explores whether MRI is a viable alternative to ultrasound as the primary imaging modality. Method: A systematic review of the literature was undertaken. A search of Medline, Cinahl, PubMed Central and Google Scholar was undertaken supplemented by a review of reference lists, author searching and review of NICE evidence base for existing guidelines. Included studies were assessed for bias using the QUADAS-2 quality assessment tool and data were extracted systematically using a purposefully designed electronic data extraction proforma. Results: Seven studies were included in final review. The age range of participants extended from 0 to 19 years. Only one study with a patient age range of 0e14 used sedation. Sensitivity estimates from the included studies ranged from 92% to 100% while specificity ranged from 89% to 100%. A significant variation in the number and type of sequences was noted between the studies. Conclusion: MRI offers high sensitivity and specificity comparable to contrast enhanced CT and greater than ultrasound as reported in the literature. Where accessibility is not a restriction, MRI is a viable alternative to ultrasound in the assessment and diagnosis of paediatric appendicitis. Clinical practice recommendations have been provided to facilitate the translation of evidence into practice

    Production of CXC and CC chemokines by human antigen-presenting cells in response to Lassa virus or closely related immunogenic viruses, and in cynomolgus monkeys with lassa fever.

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    International audienceThe pathogenesis of Lassa fever (LF), a hemorrhagic fever endemic to West Africa, remains unclear. We previously compared Lassa virus (LASV) with its genetically close, but nonpathogenic homolog Mopeia virus (MOPV) and demonstrated that the strong activation of antigen-presenting cells (APC), including type I IFN production, observed in response to MOPV probably plays a crucial role in controlling infection. We show here that human macrophages (MP) produce large amounts of CC and CXC chemokines in response to MOPV infection, whereas dendritic cells (DC) release only moderate amounts of CXC chemokines. However, in the presence of autologous T cells, DCs produced CC and CXC chemokines. Chemokines were produced in response to type I IFN synthesis, as the levels of both mediators were strongly correlated and the neutralization of type I IFN resulted in an inhibition of chemokine production. By contrast, LASV induced only low levels of CXCL-10 and CXCL-11 production. These differences in chemokine production may profoundly affect the generation of virus-specific T-cell responses and may therefore contribute to the difference of pathogenicity between these two viruses. In addition, a recombinant LASV (rLASV) harboring the NP-D389A/G392A mutations, which abolish the inhibition of type I IFN response by nucleoprotein (NP), induced the massive synthesis of CC and CXC chemokines in both DC and MP, confirming the crucial role of arenavirus NP in immunosuppression and pathogenicity. Finally, we confirmed, using PBMC samples and lymph nodes obtained from LASV-infected cynomolgus monkeys, that LF was associated with high levels of CXC chemokine mRNA synthesis, suggesting that the very early synthesis of these mediators may be correlated with a favourable outcome

    Magnetic resonance imaging in children: common problems and possible solutions for lung and airways imaging

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    Pediatric chest MRI is challenging. High-resolution scans of the lungs and airways are compromised by long imaging times, low lung proton density and motion. Low signal is a problem of normal lung. Lung abnormalities commonly cause increased signal intenstities. Among the most important factors for a successful MRI is patient cooperation, so the long acquisition times make patient preparation crucial. Children usually have problems with long breath-holds and with the concept of quiet breathing. Young children are even more challenging because of higher cardiac and respiratory rates giving motion blurring. For these reasons, CT has often been preferred over MRI for chest pediatric imaging. Despite its drawbacks, MRI also has advantages over CT, which justifies its further development and clinical use. The most important advantage is the absence of ionizing radiation, which allows frequent scanning for short- and long-term follow-up studie

    The Immunomodulatory Role of Adjuvants in Vaccines Formulated with the Recombinant Antigens Ov-103 and Ov-RAL-2 against Onchocerca volvulus in Mice.

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    BACKGROUND: In some regions in Africa, elimination of onchocerciasis may be possible with mass drug administration, although there is concern based on several factors that onchocerciasis cannot be eliminated solely through this approach. A vaccine against Onchocerca volvulus would provide a critical tool for the ultimate elimination of this infection. Previous studies have demonstrated that immunization of mice with Ov-103 and Ov-RAL-2, when formulated with alum, induced protective immunity. It was hypothesized that the levels of protective immunity induced with the two recombinant antigens formulated with alum would be improved by formulation with other adjuvants known to enhance different types of antigen-specific immune responses. METHODOLOGY/ PRINCIPAL FINDINGS: Immunizing mice with Ov-103 and Ov-RAL-2 in conjunction with alum, Advax 2 and MF59 induced significant levels of larval killing and host protection. The immune response was biased towards Th2 with all three of the adjuvants, with IgG1 the dominant antibody. Improved larval killing and host protection was observed in mice immunized with co-administered Ov-103 and Ov-RAL-2 in conjunction with each of the three adjuvants as compared to single immunizations. Antigen-specific antibody titers were significantly increased in mice immunized concurrently with the two antigens. Based on chemokine levels, it appears that neutrophils and eosinophils participate in the protective immune response induced by Ov-103, and macrophages and neutrophils participate in immunity induced by Ov-RAL-2. CONCLUSIONS/SIGNIFICANCE: The mechanism of protective immunity induced by Ov-103 and Ov-RAL-2, with the adjuvants alum, Advax 2 and MF59, appears to be multifactorial with roles for cytokines, chemokines, antibody and specific effector cells. The vaccines developed in this study have the potential of reducing the morbidity associated with onchocerciasis in humans

    Identification and functional characterization of Epstein-Barr virus DNA polymerase by in vitro transcription-translation of a cloned gene.

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    In order to identify the gene encoding the Epstein-Barr virus (EBV) DNA polymerase, a portion of the BamHI-A fragment containing the fifth leftward open reading frame (BALF5) of the EBV genome was cloned into SP6 and T7 promoter-containing vectors for in vitro transcription-translation. The RNA synthesized in vitro was used to program rabbit reticulocyte lysates, which were analyzed for the synthesis of the putative polymerase polypeptide (110 kDa) and assayed directly for EBV DNA polymerase activity. The polypeptide synthesized by the full-length BALF5 genomic fragment had a molecular mass of 110 kDa. 5'-truncated BALF5 with the first and second ATGs deleted produced 95- and 83-kDa polypeptides, respectively. All three translation products were enzymatically active and displayed resistance to high salt concentrations. The identity of the largest polypeptide as the viral polymerase was established by (i) immunoprecipitation with EBV-positive sera from patients with nasopharyngeal carcinoma and by a rabbit polyclonal antiserum prepared with a synthetic peptide derived from the DNA sequence of BALF5; (ii) identification of a polypeptide of identical size (110 kDa) immunoprecipitated from superinfected Raji cell extracts by these antibodies; and (iii) salt-resistant enzymatic activity which was neutralized by the rabbit EBV antiserum. Thus, BALF5 encodes a functional polymerase identical to that induced in superinfected Raji cells
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