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ABSTRACT: PURPOSE:: Up to one third of rheumatoid arthritis (RA) patients complain of dry eyes. The altered corneal sensitivity can be the consequence or the cause of the chronic reduction in tear secretion, or reduced tear production can cause the change of corneal sensitivity. The aim of this study was to assess the relationship among the symptoms, signs of dry eyes, and corneal sensitivity in RA and evaluate the association among the corneal sensitivity and clinical variables of RA. METHODS:: A total of 106 RA patients and 40 control subjects participated in the study. Subjective symptoms of ocular dryness were explored using Ocular Surface Disease Index (OSDI), and objective signs including Schirmer test and tear break-up time (tBUT) were measured. Corneal sensitivity was determined by evaluating the corneal touch threshold using a Cochet-Bonnet esthesiometer. Clinical assessment of RA activity included C-reactive protein, Disease Activity Score 28, and Health Assessment Questionnaire. RESULTS:: Schirmer test scores and tBUT were significantly lower and OSDI was significantly higher in RA patients. The mean corneal sensitivities significantly reduced in the patient group but failed to show any correlations with Schirmer test, tBUT, and OSDI. Corneal sensitivity showed significant negative correlation with rheumatoid factor but failed to show any correlations with C-reactive protein, Health Assessment Questionnaire, and Disease Activity Score 28. CONCLUSIONS:: Corneal sensitivity was reduced in RA patients but failed to show any association with the subjective symptoms and objective signs of dry eyes. We could assume that reduced corneal sensitivity does not represent a sign of inflammation.
Cornea 04/2012; · 1.73 Impact Factor
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Jin Sik Kim,
Jae Huyck Sung,
Kyung Seuk Song, Ji Hyun Lee,
Sun Man Kim,
Gun Ho Lee,
Kang Ho Ahn,
Jong Seong Lee,
Jae Hoon Shin,
Jung Duck Park,
Il Je Yu
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ABSTRACT: Carbon nanotubes (CNTs) have specific physico-chemical properties that are useful for the electronics, automotive, and construction industries. Yet, despite their many advantages, there is a current lack of available information on the human health and environmental hazards of CNTs. For this reason, the current study investigated the inhalation toxicity potential of multiwall CNTs (MWCNTs). Eight-week-old rats were divided into four groups (10 rats in each group), the fresh-air control (0mg/m(3)), low-concentration group (0.16mg/m(3)), middle-concentration group (0.34mg/m(3)), and high-concentration group (0.94mg/m(3)), and the whole body was exposed to MWCNTs for 5 days (6h/day). Lung cells were then isolated from five rats in each group on day 0 and 1 month after the 5-day exposure, respectively. The MWCNTs were generated by a newly designed generation system, and the MWCNT concentrations in the exposure chambers monitored in accordance with National Institute for Occupational Safety and Health (NIOSH) 0500 using a membrane filter. The MWCNTs were also sampled for an elemental carbon concentration analysis using a glass filter. The animals exhibited no significant body weight changes, abnormal clinical signs, or mortality during the experiment. A single-cell gel electrophoresis assay (Comet assay) was conducted to determine the DNA damage in lung cells obtained from the right lung. As a result, the Olive tail moments were 23.00±1.76, 30.39±1.96, 22.96±1.26, and 33.98±2.21 for the control, low-, middle-, and high-concentration groups, respectively, on day 0 postexposure. Meanwhile, 1 month postexposure, the Olive tail moments were 25.00±2.71, 28.39±3.55, 22.56±1.36, and 31.97±3.16 for the control, low-, middle-, and high-concentration groups, respectively. Thus, the MWCNTs caused a statistically significant increase in lung DNA damage at high concentration (0.94mg/m(3)) when compared with the negative control group on day 0 and 1 month postexposure.
Toxicological Sciences 04/2012; 128(2):439-48. · 4.65 Impact Factor
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ABSTRACT: To better understand the potential ecotoxicological impacts of silver nanoparticles released into freshwater environments, the Daphnia magna 48-hour immobilization test was used.
The toxicities of silver nitrate, two types of colloidal silver nanoparticles, and a suspension of silver nanoparticles were assessed and compared using standard OECD guidelines. Also, the swimming behavior and visible uptake of the nanoparticles by Daphnia were investigated and compared. The particle suspension and colloids used in the toxicity tests were well-characterized.
The results obtained from the exposure studies showed that the toxicity of all the silver species tested was dose and composition dependent. Plus, the silver nanoparticle powders subsequently suspended in the exposure water were much less toxic than the previously prepared silver nanoparticle colloids, whereas the colloidal silver nanoparticles and AgNO(3) were almost similar in terms of mortality. The silver nanoparticles were ingested by the Daphnia and accumulated under the carapace, on the external body surface, and connected to the appendages. All the silver species in this study caused abnormal swimming by the D. magna.
According to the present results, silver nanoparticles should be classified according to GHS (Globally Harmonized System of classification and labeling of chemicals) as "category acute 1" to Daphnia neonates, suggesting that the release of nanosilver into the environment should be carefully considered.
Journal of Nanobiotechnology 04/2012; 10:14. · 5.09 Impact Factor
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ABSTRACT: Aureobasidium pullulans had a maximum yield coefficient of pullulan (Y
p/s=0.24) with an initial pH of the culture broth of 6.5 in a shake-flask culture. In a batch culture, the maximum pullulan yield coefficient of 0.30 was obtained at the aeration rate of 0.5 vvm. A yeast-like form and mycelial form of cells were found at the culture broth with pH controlled at 4.5 with a maximum yield coefficient of pullulan of 0.27. However, a high portion (35%) of high molecular weight pullulan (M
w>2 000 000) was produced at pH 6.5 with a yeast-like morphology of the cells.
Biotechnology Letters 04/2001; 23(10):817-820. · 1.68 Impact Factor
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ABSTRACT: Pullulan productivity was optimized in Aureobasidium pullulans ATCC42023 with 54g glucosel–1. Pullulan with its higher molecular weight (>1000000) was produced using 2% (w/v) glucose and 3% (w/v) glucosamine together. The maximum concentration of pullulan was 8gl–1 at 140h with shake-flask culture.
Biotechnology Letters 05/2000; 22(12):987-990. · 1.68 Impact Factor
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ABSTRACT: The performance of an extracorporeal bioartificial liver (BAL) support system depends on the functional activities of the hepatocytes immobilized in the system. One of the most promising techniques in retaining liver-specific functions is co-culturing hepatocytes with other cell types, such as epithelial cells, endothelial cells and dermal fibroblasts. Primary rat hepatocytes were suspension co-cultured with rat prostate endothelial cell line (RPEn) for 20 h in a spinner vessel to form hetero-spheroids, which contain the two types of the cells, i.e., hepatocytes and endothelial cells in the same spheroid. For the subsequent culture, the hetero-spheroids were entrapped in a Ca-alginate gel bead. From the results of incorporation efficiency test, it was found that RPEn cells have a significantly higher attachment affinity to hepatocytes than human dermal fibroblast and rat liver epithelial cells. We clearly found out that RPEn cells located on the surface of the hepatocyte spheroids from immunostained paraffin sections of the hetero-spheroids. Identical with in vivo liver tissue, laminin was stained at the surface of the hetero-spheroids. Ultrastructures of liver tissue, such as bile canaliculus-like and Disse’s space-like structures, were also found at the surface of the hetero-spheroids. In vivo liver tissue, in which hepatocytes were covered with sinusoidal endothelial cells, was partly mimicked by the endothelial cell-covered hepatocyte spheroids. And the hetero-spheroids showed significantly higher and stable albumin secretion and ammonia removal activities than pure spheroids for 12 days of observations.Therefore, the endothelial cell-covered hepatocyte hetero-spheroids may offer a useful study model of epithelial–mesenchymal interactions and information about liver tissue engineering research as well as a substitute of a cell source of a BAL system.
Biochemical Engineering Journal.
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ABSTRACT: In the field of industry design, the affective response characteristic can plays a significant role that could grasp customer's attention in product. Especially, the design strategy of “affection-prerequisite” shows the importance of the trend of customer-oriented for the industry products. Up to date, in consideration of the rapidly life-cycle on industrial design field, however, how designers can retrieve customer's affective response promptly and using such information into their design work efficiently are significant, but not discussed yet. Based on this concept, the objective of this research is to present a creative stimulation system for designers. The “wisdom of crowds” was collected via the Web in order to ascertain customers' affective responses to product shapes. This data was used to create an evolutionary design system platform by using a design alternatives generation mechanism. The study involved integrating an interactive genetic algorithm into the mechanism to generate an interactive creative stimulation system. An affective design of the shape of a mobile phone was used as an example of implementation and also used as a proof of the research concept.Relevance to industryHIGA and ESC methods proposed in this research provide the usage of the affective evaluation system for acquiring the customers' affective responses in the conceptual design process of a mobile phone. This design-generation process allows the design stakeholders to realize their customers' affective responses interactively with sharing floating data among them according to the daily update of customer's evaluations.
International Journal of Industrial Ergonomics.
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ABSTRACT: The paper proposes an adaptive web system—that is, a website that is capable of changing its original design to fit user requirements. For the purpose of improving shortcomings of the website, and also to make it much easier for users to access information, the system analyzes user browsing patterns from their access records. This paper concentrates on the operating-efficiency of a website—that is, the efficiency with which a group of users browse a website. By achieving high efficiency, users spend less operating cost to accomplish a desired user goal. Based on user access data, we analyze each user's operating activities as well as their browsing sequences. With this data, we can calculate a measure of the efficiency of the user's browsing sequences. The paper develops an algorithm to accurately calculate this efficiency and to suggest how to increase the efficiency of user operations. This can be achieved in two ways: (i) by adding a new link between two web pages, or (ii) by suggesting to designers to reconsider existing inefficient links so as to allow users to arrive at their target pages more quickly. Using this algorithm, we develop a prototype to prove the concept of efficiency. The implementation is an adaptive website system to automatically change the website architecture according to user browsing activities and to improve website usability from the viewpoint of efficiency.
Advanced Engineering Informatics.
