NF-κB and CREB are involved in IL-8 production of human neutrophils induced by Trichomonas vaginalis-derived secretory products.

Trichomonas vaginalis is a flagellated lumen-dwelling extracellular protozoan parasite that causes human trichomoniasis via sexual intercourse. Human neutrophils play a crucial role in acute tissue inflammatory responses in T. vaginalis infection. In this study, we investigated the signaling mechanism of neutrophil responses when stimulated with T. vaginalis-derived secretory products (TvSP), which were collected from 1×10(7) live trichomonads. Incubation of human neutrophils isolated from peripheral blood with TvSP induced up-regulation of IL-8 protein secretion. In addition, stimulation with TvSP induced phosphorylation of NF-κB and CREB in neutrophils. Moreover, TvSP-induced IL-8 production was also significantly inhibited by pretreatment of neutrophils with iκB inhibitor or CREB inhibitor. These results suggest that transcription factors NF-κB and CREB are involved in IL-8 production in human neutrophils induced by stimulation with T. vaginalis infection.ope

Entamoeba histolytica-secreted cysteine proteases induce IL-8 production in human mast cells via a PAR2-independent mechanism

Entamoeba histolytica is an extracellular tissue parasite causing colitis and occasional liver abscess in humans. E. histolytica-derived secretory products (SPs) contain large amounts of cysteine proteases (CPs), one of the important amoebic virulence factors. Although tissue-residing mast cells play an important role in the mucosal inflammatory response to this pathogen, it is not known whether the SPs induce mast cell activation. In this study, when human mast cells (HMC-1 cells) were stimulated with SPs collected from pathogenic wild-type amoebae, interleukin IL-8 mRNA expression and production were significantly increased compared with cells incubated with medium alone. Inhibition of CP activity in the SPs with heat or the CP inhibitor E64 resulted in significant reduction of IL-8 production. Moreover, SPs obtained from inhibitors of cysteine protease (ICP)-overexpressing amoebae with low CP activity showed weaker stimulatory effects on IL-8 production than the wild-type control. Preincubation of HMC-1 cells with antibodies to human protease-activated receptor 2 (PAR2) did not affect the SP-induced IL-8 production. These results suggest that cysteine proteases in E. histolytica-derived secretory products stimulate mast cells to produce IL-8 via a PAR2-independent mechanism, which contributes to IL-8-mediated tissue inflammatory responses during the early phase of human amoebiasis.ope

Amoebic PI3K and PKC Is Required for Jurkat T Cell Death Induced by Entamoeba histolytica

The enteric protozoan parasite Entamoeba histolytica is the causative agent of human amebiasis. During infection, adherence of E. histolytica through Gal/GalNAc lectin on the surface of the amoeba can induce caspase-3-dependent or -independent host cell death. Phosphorylinositol 3-kinase (PI3K) and protein kinase C (PKC) in E. histolytica play an important function in the adhesion, killing, or phagocytosis of target cells. In this study, we examined the role of amoebic PI3K and PKC in amoeba-induced apoptotic cell death in Jurkat T cells. When Jurkat T cells were incubated with E. histolytica trophozoites, phosphatidylserine (PS) externalization and DNA fragmentation in Jurkat cells were markedly increased compared to those of cells incubated with medium alone. However, when amoebae were pretreated with a PI3K inhibitor, wortmannin before being incubated with E. histolytica, E. histolytica-induced PS externalization and DNA fragmentation in Jurkat cells were significantly reduced compared to results for amoebae pretreated with DMSO. In addition, pretreatment of amoebae with a PKC inhibitor, staurosporine strongly inhibited Jurkat T cell death. However, E. histolytica-induced cleavage of caspase-3, -6, and -7 were not inhibited by pretreatment of amoebae with wortmannin or staurosporin. In addition, we found that amoebic PI3K and PKC have an important role on amoeba adhesion to host compartment. These results suggest that amebic PI3K and PKC activation may play an important role in caspase-independent cell death in Entamoeba-induced apoptosis.ope

Degradation of the transcription factors NF-kB, STAT3, and STAT5 is involved in Entamoeba histolytica-induced cell death in Caco-2 colonic epithelial cells

Entamoeba histolytica is a tissue-invasive protozoan parasite causing dysentery in humans. During infection of colonic tissues, amoebic trophozoites are able to kill host cells via apoptosis or necrosis, both of which trigger IL-8-mediated acute inflammatory responses. However, the signaling pathways involved in host cell death induced by E. histolytica have not yet been fully defined. In this study, we examined whether calpain plays a role in the cleavage of pro-survival transcription factors during cell death of colonic epithelial cells, induced by live E. histolytica trophozoites. Incubation with amoebic trophozoites induced activation of m-calpain in a time- and dose-dependent manner. Moreover, incubation with amoebae resulted in marked degradation of STAT proteins (STAT3 and STAT5) and NF-κB (p65) in Caco-2 cells. However, IκB, an inhibitor of NF-κB, was not cleaved in Caco-2 cells following adherence of E. histolytica. Entamoeba-induced cleavage of STAT proteins and NF-κB was partially inhibited by pretreatment of cells with a cell-permeable calpain inhibitor, calpeptin. In contrast, E. histolytica did not induce cleavage of caspase-3 in Caco-2 cells. Furthermore, pretreatment of Caco-2 cells with a calpain inhibitor, calpeptin (but not the pan-caspase inhibitor, z-VAD-fmk) or m-calpain siRNA partially reduced Entamoeba-induced DNA fragmentation in Caco-2 cells. These results suggest that calpain plays an important role in E. histolytica-induced degradation of NF-κB and STATs in colonic epithelial cells, which ultimately accelerates cell death.ope

Revisiting vascular patency after spleen-preserving laparoscopic distal pancreatectomy with conservation of splenic vessels

BACKGROUND: We evaluated vascular patency and potential changes in preserved spleens after laparoscopic spleen-preserving distal pancreatectomy (SPDP) with conservation of both splenic vessels. METHODS: We retrospectively analyzed the patency of conserved splenic vessels in patients who underwent laparoscopic or robotic splenic vessel-conserving SPDP from January 2006 to August 2010. The patency of the conserved splenic vessels was evaluated by abdominal computed tomography and classified into three grades according to the degree of severity. RESULTS: Among 30 patients with splenic vessel-conserving laparoscopic SPDP, 29 patients with complete follow-up data were included in this study. During the follow-up period (median: 13.2 months), grades 1 and 2 splenic arterial obliteration were observed in one patient each. A total of five patients (17.2%) showed grade 1 or 2 obliteration in conserved splenic veins. Most patients (82.8%) had patent conserved splenic vein. Four patients (13.8%) eventually developed collateral venous vessels around gastric fundus and reserved spleen, but no spleen infarction was found, and none presented clinical relevant symptoms, such as variceal bleeding. There was no statistical difference in vascular patency between the laparoscopic and robotic groups (P > 0.05). CONCLUSIONS: Most patients showed intact vascular patency in conserved splenic vessels and no secondary changes in the preserved spleen after laparoscopic splenic vessel-conserving SPDP.ope

Genomic characteristics of invasive mucinous adenocarcinoma of the lung with multiple pulmonary sites of involvement

Invasive mucinous adenocarcinoma (IMA) of the lung frequently presents with diffuse pneumonic-type features or multifocal lesions, which are regarded as a pattern of intrapulmonary metastases. However, the genomics of multifocal IMAs have not been well studied. We performed whole exome sequencing on samples taken from 2 to 5 regions in seven patients with synchronous multifocal IMAs of the lung (24 regions total). Early initiating driver events, such as KRAS, NKX2-1, TP53, or ARID1A mutations, are clonal mutations and were present in all multifocal IMAs in each patient. The tumor mutational burden of multifocal IMAs was low (mean: 1.13/mega base), but further analyses suggested intra-tumor heterogeneity. The mutational signature analysis found that IMAs were predominantly associated with endogenous mutational process (signature 1), APOBEC activity (signatures 2 and 13), and defective DNA mismatch repair (signature 6), but not related to smoking signature. IMAs synchronously located in the bilateral lower lobes of two patients with background usual interstitial pneumonia had different mutation types, suggesting that they were double primaries. In conclusion, genomic evidence found in this study indicated the clonal intrapulmonary spread of diffuse pneumonic-type or multifocal IMAs, although they can occur in multicentric origins in the background of usual interstitial pneumonia. IMAs exhibited a heterogeneous genomic landscape despite the low somatic mutation burden. Further studies are warranted to determine the clinical significance of the genomic characteristics of IMAs in expanded cohorts.ope

MRI findings of uncommon non-hepatocyte origin primary liver tumours with pathological correlation

The objective of this article was to illustrate the MRI findings of uncommon non-hepatocyte origin primary liver tumours, correlate them with the pathological features and discuss differential diagnoses. In conclusion, the MRI findings of uncommon benign and malignant non-hepatocyte-origin primary liver tumours vary. Awareness of characteristic MRI features can aid differential diagnosis and prevent unnecessary surgery.ope

18F-FDG PET Metabolic Parameters and MRI Perfusion and Diffusion Parameters in Hepatocellular Carcinoma: A Preliminary Study

OBJECTIVES: Glucose metabolism, perfusion, and water diffusion may have a relationship or affect each other in the same tumor. The understanding of their relationship could expand the knowledge of tumor characteristics and contribute to the field of oncologic imaging. The purpose of this study was to evaluate the relationships between metabolism, vasculature and cellularity of advanced hepatocellular carcinoma (HCC), using multimodality imaging such as ¹⁸F-FDG positron emission tomography (PET), dynamic contrast enhanced (DCE)-MRI, and diffusion weighted imaging(DWI). MATERIALS AND METHODS: Twenty-one patients with advanced HCC underwent ¹⁸F-FDG PET, DCE-MRI, and DWI before treatment. Maximum standard uptake values (SUV(max)) from ¹⁸F-FDG-PET, variables of the volume transfer constant (K(trans)) from DCE-MRI and apparent diffusion coefficient (ADC) from DWI were obtained for the tumor and their relationships were examined by Spearman's correlation analysis. The influence of portal vein thrombosis on SUV(max) and variables of K(trans) and ADC was evaluated by Mann-Whitney test. RESULTS: SUV(max) showed significant negative correlation with K(trans)(max) (ρ = -0.622, p = 0.002). However, variables of ADC showed no relationship with variables of K(trans) or SUV(max) (p>0.05). Whether portal vein thrombosis was present or not did not influence the SUV max and variables of ADC and K(trans) (p>0.05). CONCLUSION: In this study, SUV was shown to be correlated with K(trans) in advanced HCCs; the higher the glucose metabolism a tumor had, the lower the perfusion it had, which might help in guiding target therapy.ope

Number of target lesions for EASL and modified RECIST to predict survivals in hepatocellular carcinoma treated with chemoembolization

PURPOSES: To date, most studies about the optimal number of target lesions for enhancement criteria for hepatocellular carcinoma (HCC) have focused on cross-sectional analyses of concordance. We investigated the optimal number of target lesions for European Association for the Study of the Liver (EASL) and modified Response Evaluation Criteria in Solid Tumors (mRECIST) guidelines in predicting overall survival (OS). EXPERIMENTAL DESIGN: We analyzed 254 consecutive treatment-naïve patients with HCC having at least 2 measurable target lesions undergoing transarterial chemoembolization. Kappa values for intermethod agreement of treatment responses were calculated for comparisons between use of maximum of 1, 2, 3, 4, or 5 targets versus use of all target lesions. Prognostic values of radiologic assessments according to number of target lesions for predicting OS were expressed as C-index. RESULTS: By EASL and mRECIST guidelines, κ values between responses assessing the longest 2, 3, 4, or 5 targets and assessing all targets were 0.924, 0.977, 1.000, or 1.000 and 0.907, 0.959, 1.000, or 1.000, respectively, whereas those between responses assessing only one target and assessing all target lesions were 0.723 and 0.666, respectively. C-index when measuring the longest 1, 2, 3, 4, 5, and all targets was similar, ranging from 0.739 to 0.749 for EASL criteria and from 0.750 to 0.759 for mRECIST. From Cox regression analyses, radiologic response from each calculation method showed independently significant effects on OS for both guidelines, regardless of number of target lesions. CONCLUSIONS: Prognostic values for predicting OS were similar regardless of number of target lesions. Assessing the 2 largest targets rather than only 1 index lesion could be recommended considering high concordances from cross-sectional analyses.ope

수도권 자연보전권역에서 토지이용 규제가 지피변화에 미치는 영향

학위논문(석사)--서울대학교 환경대학원 :환경계획학과,1998.Maste