Erythroblast differentiation at spleen in Q137E mutant ribosomal protein S19 gene knock-in C57BL/6J mice

We recently found that erythroblast-like cells derived from human leukaemia K562 cells express C5a receptor (C5aR) and produce its antagonistic and agonistic ligand ribosomal protein S19 (RP S19) polymer, which is cross-linked between K122 and Q137 by tissue transglutaminases. RP S19 polymer binds to the reciprocal C5aRs on erythroblast-like cells and macrophage-like cells derived from human monocytic THP-1 cells and promotes differentiation into reticulocyte-like cells through enucleation in vitro. To examine the roles of RP S19 polymer in mouse erythropoiesis, we prepared Q137E mutant RP S19 gene knock-in C57BL/6J mice. In contrast to wild-type mice, erythroblast numbers at the preliminary stage (CD71^high/TER119^low) in spleen based on transferrin receptor (CD71) and glycophorin A (TER119) values and erythrocyte numbers in orbital artery bloods were not largely changed in knock-in mice. Conversely, erythroblast numbers at the early stage (CD71^high/TER119^high) were significantly decreased in spleen by knock-in mice. The reduction of early erythroblast numbers in spleen was enhanced by the phenylhydrazine-induced pernicious anemia model knock-in mice and was rescued by a functional analogue of RP S19 dimer S-tagged C5a/RP S19. These data indicated that RP S19 polymer plays the roles in the early erythroblast differentiation of C57BL/6J mouse spleen.     

Effect of hydrogen peroxide on interleukin-8 synthesis and death of Caco-2 cells

Intestinal epithelial cells can secrete interleukin-8 (IL-8), among other substances in response to different stimuli, which plays an important role in mucosal immune response. Above a certain concentration range, hydrogen peroxide causes cell death by necrosis or apoptosis. We investigated the time- and dose-dependent induction of IL-8 by hydrogen peroxide in the human colon adenocarcinoma cell line Caco-2. In addition, the changes of transepithelial electrical resistance and cell death induction in response to hydrogen peroxide were studied. Nonfilter-grown and filter-grown Caco-2 cells were employed in our experiments. Interleukin-8 synthesis was measured by ELISA. Necrosis was determined by DAPI staining of cells, apoptosis by measuring caspase-3 enzyme activity or annexin V staining. In nonfilter-grown Caco-2 cells, 1 mM of hydrogen peroxide induced the highest level of IL-8 production 24 hr after treatment. In filter-grown Caco-2 cells, IL-8 was produced only on the apical side in response to 1 mM of hydrogen peroxide. This level was 10-fold lower than that measured in nonfilter-grown Caco-2 cells 24 hr after the treatment. In filter-grown Caco-2 cells 10 mM hydrogen peroxide induced the highest IL-8 level on the apical as well as basolateral side. Transepithelial electrical resistance decreased markedly upon application of 40 mM hydrogen peroxide. Late effect of hydrogen peroxide was observed in nonfilter-grown Caco-2 cells, as 1 mM hydrogen peroxide caused necrosis after 24 hr while early-necrosis induction occurred in filter-grown cells exposed to 40 mM of hydrogen peroxide after 1 hr. Filter-grown Caco-2 cells were less sensitive to hydrogen peroxide than the nonfilter-grown ones.     

Nocturia in older men

Nocturia is a common and bothersome symptom that impacts on sleep-quality and quality of life. Nocturia often has a multi-factorial etiology which makes thorough assessment of the complaint indispensable. This review summarizes the definition of nocturia, its epidemiology, clinical presentation, pathophysiology, diagnostics, and treatment options with special reference to older men. Nocturia is defined as a nocturnal voiding frequency of two or more, based on impact on quality of life. It is very prevalent in older men. Apart from the negative effects of sleep-disruption, it may be a risk-factor for hip fractures and increased mortality. Most common causes are: nocturnal polyuria, 24-h polyuria, overactive bladder (sometimes due to BPH) and sleep disturbance. A clear understanding of the etiology in the individual patient is indispensable when addressing the various possible causes and co-morbidities. Most important tool for this is the frequency-volume chart, but also patient history, physical examination and serum analysis. For treatment, lifestyle adjustments are often helpful. Medical therapy with 5-alpha reductase inhibitors, alpha-blockers, a combination of the two, or anti-muscarinics, has a limited effect. Most important medical option is desmopressin (arginine vasopressin analogue); however, treatment with this drug is limited to men under 65 years mainly due to the risk of hyponatraemia.     

Histamine and T helper cytokine–driven epithelial barrier dysfunction in allergic rhinitis

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Triptolide alters barrier function in renal proximal tubular cells in rats

Alteration of the tight junction complex in renal epithelial cells can affect renal barrier function and perturb normal kidney homeostasis. The objective of the present study was to determine whether triptolide could affect tight junctions in the proximal tubule epithelial cells both in vivo and in vitro. Wistar rats were gavaged with triptolide at 0, 100, 200 or 400 μg/kg/day for 28 days. Pathologic examination of the kidney showed that triptolide primarily affected the proximal tubules. The nephrotoxicity of triptolide is morphologically characterized by the detachment of the proximal tubular epithelial cells from each other. Immunohistochemical analysis showed that there was marked alteration in the localization of Zonula Occludens 1 protein (ZO-1) in the proximal tubule epithelium. Additionally, the uptake of FITC-dextran, a marker of fluid phase endocytosis in the proximal tubule, was considerably lower in triptolide-treated animals than in normal rats. Supported by these results, we detected significant increases in blood urea nitrogen (BUN) but not of creatinine (Cr) in rats treated with triptolide, indicating damage to the proximal tubules. Furthermore, triptolide treatment caused an alteration of the tight junction complex, resulting in changes in paracellular permeability in NRK-52E cells in vitro. Taken together, these results suggest that triptolide induced renal toxicity in rats and that the mechanism of toxicity was related to the disruption of cell–cell junctions and alterations of the paracellular permeability in the proximal tubule.     

Laundry detergents and detergent residue after rinsing directly disrupt tight junction barrier integrity in human bronchial epithelial cells

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Efficacy and safety of combination therapy of chemoembolization and radiofrequency ablation with different time intervals for hepatocellular carcinoma patients

Background and objectives

Combination of transcatheter arterial chemoembolization (TACE) and radiofrequency ablation (RFA) has become an effective alternative therapy for hepatocellular carcinoma (HCC). In clinical practice, the choice of time interval between TACE and RFA is a key point for curative effect, but optimal time interval is uncertain in guidelines. We aim to explore the optimal time interval for HCC patients of Child-Pugh classification A or B.