A large mobility of hydrophilic molecules at the outmost layer controls the protein adsorption and adhering behavior with the actin fiber orientation of human umbilical vein endothelial cells (HUVEC)

Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX–PMB and OMe-PRX–PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX–PMB surface much more than PRX–PMB and PMB-block–PEG–block-PMB (PEG–PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG–PMB, PRX–PMB, and OMe-PRX–PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX–PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces.     

Seasonal Specificity of Seasonal Allergens and Validation of the ARIA Classification in Korea

Purpose

In Korea, tree pollens are known to be prevalent in spring, grass pollens in summer and weed pollens in autumn. However, few studies have revealed their seasonal specificity for allergic rhinitis symptoms. An ARIA (Allergic Rhinitis and its Impact on Asthma) classification of allergic rhinitis was recently introduced and its clinical validation has not been well proved. The aim of this study was to evaluate the seasonal specificity of seasonal allergens and to validate the ARIA classification with the conventional seasonal and perennial allergic rhinitis (SAR/PAR) classification.

Methods

Two hundred twenty six patients with allergic rhinitis were included in this study. The patients were classified according to the sensitized allergens and the ARIA classifications. A questionnaire survey was performed and the data on the seasonal symptom score, the severity of symptoms and the SNOT (sinonasal outcome test)-20 score was obtained and the data was analyzed and compared between the conventional SAR/PAR classification and the ARIA classification.

Results

Seasonal pollens (tree, grass, weed) were not specific to the pollen peak season and the patients'' symptoms were severe during spring and autumn regardless of the offending pollens. More than 60% of the patients with SAR showed persistent symptoms and 33% of the patients with perennial allergic rhinitis (PAR) had intermittent symptoms, showing the lack of association between the SAR/PAR/PAR+SAR classification and the ARIA classification. The ARIA classification showed better association not only with the symptomatic score, but also with the SNOT-20 score, which showed better validity than the conventional SAR/PAR classifications.

Conclusions

Seasonal pollens were not specific to their season of prevalence in terms of the severity of symptoms, and the ARIA classification showed better representation of allergic symptoms and quality of life (SNOT-20 score) than did the SAR/PAR classification.     

The effect of Er:YAG laser irradiation on hydroxyapatite-coated implants and fluoride-modified TiO2-blasted implant surfaces: a microstructural analysis

The purpose of this study was to evaluate the microscopic changes and surface roughness on hydroxyapatite (HA)-coated implants following exposure to different powers and durations of Er:YAG laser irradiation in order to determine the proper pulse energy level and irradiation time. Ten HA-coated implants and ten fluoride-modified TiO₂ implants were used. The implants were divided into a control (one implant) and test group (nine implants) for each implant type. Implants in the test groups were sub-divided into three groups (three implants per group) based on the applied laser pulse energy and irradiation time. The measurement of surface roughness was performed on all implants in the test groups using a white light interferometer before and after laser irradiation. R _a values were recorded and compared in order to evaluate changes in surface roughness. For HA-coated implants, the R _a values increased in all test groups after laser irradiation. However, mean R _a values in the fluoride-modified TiO₂-blasted implant test group were decreased after irradiation. There was no statistical difference. Scanning electron microscope analysis revealed surface alterations in both the HA-coated and fluoridated TiO₂-blasted implants irradiated for 1.5 min at 100 mJ/pulse, 10 Hz. When the pulse energy and irradiation time increased, greater surface alterations, including surface flattening and microfractures, were observed. In conclusion, the results of the current study suggest that no changes could be observed in both HA-coated implants and fluoride-modified TiO₂-blasted implants after irradiation at an intensity of 100 mJ/pulse, 10 Hz for 1 min performed to achieve surface detoxification.     

Generation of lymphocytes potentiated against leukemic lymphoblasts by stimulation using leukemic cell lysate-pulsed dendritic cells in patients with acute lymphoblastic leukemia and measurement of in vitro anti-leukemic cytotoxicity

Using granulocyte-macrophage colony stimulating factor, interleukin4 and tumor necrosis factor α, we generated dendritic cells (DCs) from mononuclear cells isolated from the peripheral blood (PB) of eight patients with acute lymphoblastic leukemia (ALL), who were in complete remission (CR), and pulsed these DCs with leukemic cell lysates. Specific cytotoxicity assays were performed by incubation of effector cells (lymphocytes generated from cryopreserved mononuclear cells isolated in CR state of ALL) and targets (cryopreserved leukemic cells at diagnosis). Patients showing decreased cytotoxicity had poorer clinical courses. When we measured lymphocyte subsets, we found positive correlations between cytotoxicity levels and the proportions of T lymphocytes and CD8+ T lymphocytes, but negative correlations between cytotoxicity levels and the proportions of NK cells and regulatory T lymphocytes. In conclusion, we show here that leukemia-specific autologous DCs can be generated from the PB of ALL patients in CR, that the incubation of these DCs with leukemic cell lysates can generate lymphocytes potentiated against leukemic cells, and that relationships are evident among all of cytotoxicity, lymphocyte subsets, and patient prognosis.     

The application of SFDI and LSI system to evaluate the blood perfusion in skin flap mouse model

Lasers in Medical Science - The aim of this study is to evaluate whether the blood perfusion to tissues for detecting ischemic necrosis can be quantitatively monitored by spatial frequency domain...     

Alleviation of capsular formations on silicone implants in rats using biomembrane-mimicking coatings

Despite their popular use in breast augmentation and reconstruction surgeries, the limited biocompatibility of silicone implants can induce severe side effects, including capsular contracture – an excessive foreign body reaction that forms a tight and hard fibrous capsule around the implant. This study examines the effects of using biomembrane-mimicking surface coatings to prevent capsular formations on silicone implants. The covalently attached biomembrane-mimicking polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), prevented nonspecific protein adsorption and fibroblast adhesion on the silicone surface. More importantly, in vivo capsule formations around PMPC-grafted silicone implants in rats were significantly thinner and exhibited lower collagen densities and more regular collagen alignments than bare silicone implants. The observed decrease in α-smooth muscle actin also supported the alleviation of capsular formations by the biomembrane-mimicking coating. Decreases in inflammation-related cells, myeloperoxidase and transforming growth factor-β resulted in reduced inflammation in the capsular tissue. The biomembrane-mimicking coatings used on these silicone implants demonstrate great potential for preventing capsular contracture and developing biocompatible materials for various biomedical applications.     

Clinicopathologic characteristics of paranasal sinus fungus ball: retrospective,multicenter study in Korea

European Archives of Oto-Rhino-Laryngology - Fungus ball (FB) is the most common type of fungal rhinosinusitis and the prevalence of FB has increased over the past 10 years. The aim of...     

Tissue response to poly(L-lactic acid)-based blend with phospholipid polymer for biodegradable cardiovascular stents

A temporary cardiovascular stent device by bioabsorbable materials might reduce late stent thrombosis. A water-soluble amphiphilic phospholipid polymer bearing phosphorylcholine groups (PMB30W) was blended with a high-molecular-weight poly(l-lactic acid) (PLLA) to reduce unfavorable tissue responses at the surface. The PLLA implants and the polymer blend (PLLA/PMB30W) implants were inserted into subcutaneous tissues of rats, the infrarenal aorta of rats, and the internal carotid arteries of rabbits. After 6 months subcutaneous implantation, the PLLA/PMB30W maintained high density of phosphorylcholine groups on the surface without a significant bioabsorption. After intravascular implantation, the cross-sectional areas of polymer tubing with diameters less than 1.6?mm were histomorphometrically measured. Compared to the PLLA tubing, the PLLA/PMB30W tubing significantly reduced the thrombus formation during 30?d of implantation. Human peripheral blood mononuclear cells were cultured on the PLLA and the PLLA/PMB30W to compare inflammatory reactions. Enzyme-linked immunosorbent assay quantified substantially decreased proinflammatory cytokines in the case of the PLLA/PMB30W. They were almost the same level as the negative controls. Thus, we conclude that the phosphorylcholine groups could reduce tissue responses significantly both in vivo and in vitro, and the PLLA/PMB30W is a promising material for preparing temporary cardiovascular stent devices.     

Intrahepatic cholangiocarcinoma arising in chronic advanced liver disease and the cholangiocarcinomatous component of hepatocellular cholangiocarcinoma share common phenotypes and cholangiocarcinogenesis

Xu J, Sasaki M, Harada K, Sato Y, Ikeda H, Kim J‐H, Yu E & Nakanuma Y
(2011) Histopathology  59 , 1090–1099
Intrahepatic cholangiocarcinoma arising in chronic advanced liver disease and the cholangiocarcinomatous component of hepatocellular cholangiocarcinoma share common phenotypes and cholangiocarcinogenesis Aims: Intrahepatic cholangiocarcinomas (ICCs) are known to arise in cases of non‐biliary, chronic advanced liver disease (CALD), but their clinicopathological features remain unexplored. The aim of this study was to compare the histological and immunohistochemical ICCs arising inCALD with those arising in livers with non‐specific reactive (NSR) changes. Methods and results: Seventy‐one cases of ICC arising in CALD were compared with ICCs arising in livers with NSR changes, including normal livers (72 cases) and the cholangiocarcinomatous (CC) component of hepatocellular cholangioncarcinomas (HC‐CCs) (30 cases). The expression of mucin was higher in ICC with NSR changes, whereas it was relatively low in ICC with CALD and the CC component of HC‐CC. The expression of biliary markers [cytokeratin (CK)7, CK19, epithelial membrane antigen, and epithelial cell adhesion molecule (EpCAM)] was lower in CC with CALD and in the CC component of HC‐CC than in CC with NSR changes. The expression of hepatic progenitor cell markers [neural cell adhesion molecule (NCAM) and c‐kit] was higher in ICC with CALD and the CC component of HC‐CC than in ICC with NSR changes. EpCAM and CK19 were constantly expressed in cultured CC cells, whereas NCAM was infrequently expressed in cultured CC cells. Conclusions: The carcinogenesis of ICC arising in CALD and the ICC component of HC‐CC, each showing similar features, may involve hepatic progenitor cells.