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AIM: To evaluate the clinical characteristics and progression of liver abscess caused by toxocara. METHODS: We retrospectively reviewed the medical records of patients with serum IgG antibody to Toxocara canis and liver abscess diagnosed using abdominal computed tomography between February 2010 and February 2015. Among 84 patients exhibiting serum IgG antibody to Toxocara canis, 34 patients were diagnosed with liver asbscess and treated with albendazole. A follow-up period of 1 year was conducted. RESULTS: Mean patient age was 53 (34-79) years, with 26 (76.5%) patients being male. Twenty-one (61.7%) patients were moderate or heavy drinkers, 23 (67.6%) patients had a history of eating raw meat or liver and 6 (17.6%) patients owned pet dogs or cats. Main patient symptoms consisted of right upper quadrant pain, fever, and fatigue; 18 (52.9%) patients, however, presented with no symptoms. Lung involvement was detected in 444 (11.7%) patients. The eosinophil count increased in 29 (85.3%) patients at initial diagnosis, and decreased in most patients after albendazole treatment. The initial serum IgE level increased in 25 (73.5%) patients, but exhibited various response levels after albendazole treatment. Liver abscess formation improved in all patients. CONCLUSION: The liver abscess was improved with albendazole treatment.

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Strongyloides stercoralis is a soil transmitted intestinal nematode that is endemic in the tropical and subtropical regions. In most individuals who are infected, chronic, usually asymptomatic, gastrointestinal infection persists. But, in immunocompromized hosts or in patients receiving immunosuppressive therapy, autoinfection of S. stercoralis may result in the dissemination of larvae, leading to fatal hyperinfection and increased rate of complications. We report a case of hyperinfective strongyloidiasis with bacterial meningitis in a patient receiving steroid therapy. Strongyloidiasis was diagnosed by the presence of filariform larvae of S. stercoralis in the bronchoalveolar lavage cytology and upper gastrointestinal endoscopic biopsy specimen. Her clinical symptoms had progressively aggravated and developed bacterial meningitis during treatment. She died despite aggressive antibiotic and antihelminthic therapy.

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During ischemia-reperfusion injury, brief pre-exposure to oxidative stress renders organs resistant to subsequent severe damage. NF-κB is a transcription factor that is involved in reperfusion-induced inflammatory and immune responses. The activity of NF-κB has been shown to be modulated by oxidative stress in various cell types through different pathways. We studied the effect of pre-exposure to oxidative stress on subsequent NF-κB activation in TNFα-stimulated HEK293 cells. The cells were transiently exposed to 0.5 mM H(2)O(2) for 20 min, prior to stimulation with TNFα, and the subsequent expression of NF-κB-dependent genes and the levels of NF-κB signaling molecules were measured. Pre-exposure to H(2)O(2) significantly delayed the TNFα-induced expression of an NF-κB reporter gene and inflammatory proteins (intercellular adhesion molecule-1 and IL-1ß). The degradation of inhibitor of NF-κB α (IκBα) and the nuclear translocation of NF-κB were also delayed by H(2)O(2) treatment, whereas IκBα phosphorylation and IκB kinase activity were not changed. When we examined the ubiquitin/proteosome pathway in H(2)O(2)-treated cells, we could not detect significant changes in proteosomal peptidase activities, but we were able to detect a delay of IκBα poly-ubiquitination. Our results suggest that transient exposure to oxidative stress temporally inhibits NF-κB-dependent gene expression by suppressing the poly-ubiquitination of phosphorylated IκBα in HEK293 cells.

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N-Tosyl-L-phenylalanine chloromethyl ketone (TPCK), a serine/cysteine protease inhibitor, has been reported to inhibit expression of inflammatory mediators by blocking nuclear factor-kappaB (NF-kappaB) activation. We examined the effect of TPCK on the NF-kappaB activation pathway in HeLa cells by measuring the activity of IkappaB kinase (IKK) and p65/RelA-DNA binding. TPCK inhibited tumor necrosis factor-alpha-induced IKK activation and directly blocked IKK activity in vitro. TPCK-induced inhibition of NF-kappaB and IKK activation was abrogated by addition of the thiol-reducing agent dithiothreitol, suggesting that the effect of TPCK occurred through modification of a thiol group in IKK. Consistent with this, an IKKbeta mutant in which Cys-179 was substituted with alanine was not more susceptible to TPCK. Our result also showed that TPCK inhibits the DNA binding of transiently expressed p65/RelA in HeLa cells. Inhibition of p65/RelA-DNA binding was recovered in the presence of dithiothreitol, and substitution of Cys-38 with Ser in p65/RelA rendered the protein resistant to inhibition by TPCK. Mass spectrometry analysis of IKKbeta and p65/RelA isolated from cells treated with TPCK by UPLC-ESI-Q-TOF tandem MS revealed the labeling of Cys-179 of IKKbeta and Cys-38 of p65/RelA with a tosylphenylalanylmethyl group. These results suggest that TPCK inhibits NF-kappaB activation by directly modifying thiol groups on two different targets: Cys-179 of IKKbeta and Cys-38 of p65/RelA.

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N-tosyl-l-phenylalanine chloromethyl ketone (TPCK) is known to inhibit NF-kappaB activation and the expression of inflammation mediators in cultured cells. We measured the potential of TPCK to inhibit the pathogenesis of collagen-induced arthritis by blocking NF-kappaB activation. Arthritis was induced in DBA/1J mice by the injection of bovine type II collagen in adjuvant on days 0 and 14. Mice received either TPCK (3 or 10 mg/kg, i.p.) or vehicle three times a week for 3 weeks starting on day 21. TPCK moderately reduced clinical disease activity scores, whereas it markedly suppressed histological indications of joint destruction. In vitro production of tumor necrosis factor-alpha, interleukin-6, and monocyte chemotactic protein-1 from lipopolysaccharide-stimulated spleen cells was also reduced by in vivo treatment with TPCK. Proliferation of cells isolated from spleen or draining lymph nodes and production of interferon-gamma and interleukin-17 in response to stimulation with type II collagen was decreased by TPCK. Moreover, nuclear NF-kappaB activity induced by collagen immunization was significantly reduced in mice treated with TPCK. Finally, osteoclast differentiation of bone marrow cells induced by macrophage colony-stimulating factor and receptor activator of NF-kappaB ligand was completely inhibited by TPCK. These results indicate that TPCK attenuates collagen-induced arthritis and bone erosion by suppressing NF-kappaB activation and thus expression of inflammatory and osteoclastogenic genes.

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