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91.

Purpose

Development of ex vivo model to study pathogenesis, inflammation and treatment modalities for pterygium.

Methods

Pterygium obtained from surgery was cultivated (3 months). Gravitational attachment method using viscoelastic facilitated adherence of graft and outgrowing cells. Medium contained serum as the only growth supplement with no use of scaffolds. Surface profiling of the multi-layered cells for hematopoietic- and mesenchymal stem cell markers was performed. Examination of cells by immunohistochemistry using pluripotency, oxidative stress, stemness, migration and proliferation, epithelial and secretory markers was performed. The effect of anti-proliferative agent Mitomycin C upon secretion of pro-inflammatory cytokines IL-6 and IL-8 was assessed.

Results

Cells showed high expression of migration- (CXCR4), secretory- (MUC1, MUC4) and oxidative damage- (8-OHdG) markers, and low expression of hypoxia- (HIF-1α) and proliferation- (Ki-67) markers. Moderate and low expression of the pluripotency markers (Vimentin and ΔNp63) was present, respectively, while the putative markers of stemness (Sox2, Oct4, ABCG-2) and epithelial cell markers- (CK19, CK8-18) were weak. The surface marker profile of the outgrowing cells revealed high expression of the hematopoietic marker CD47, mesenchymal markers CD90 and CD73, minor or less positivity for the hematopoietic marker CD34, mesenchymal marker CD105, progenitor marker CD117 and attachment protein markers while low levels of IL-6 and IL-8 secretion ex vivo, were inhibited upon Mitomycin C treatment.

Conclusion

Ex vivo tissue engineered pterygium consists of a mixture of cells of different lineage origin, suitable for use as a disease model for studying pathogenesis ex vivo, while opening possibilities for new treatment and prevention modalities.  相似文献   
92.
93.
Predicate Abstraction of ANSI-C Programs Using SAT   总被引:1,自引:0,他引:1  
Predicate abstraction is a major method for verification of software. However, the generation of the abstract Boolean program from the set of predicates and the original program suffers from an exponential number of theorem prover calls as well as from soundness issues. This paper presents a novel technique that uses an efficient SAT solver for generating the abstract transition relations of ANSI-C programs. The SAT-based approach computes a more precise and safe abstraction compared to existing predicate abstraction techniques.  相似文献   
94.
Delayed nonmatching to sample (DNMS) is used to test the recognition memory function dependent on the medial temporal lobe. Children cannot succeed on this task until about 21 months. Because robust recognition is present well before then, the late emergence of another ability must account for the late success on DNMS. Evidence is presented here that the critical late-maturing confidence is the ability to grasp the relation between stimulus and reward—that is, to understand that the stimulus is a symbol or marker for the reward. Infants of 9 and 12 months were tested on 3 conditions of DNMS. A sample object was presented. After a delay, the sample and a novel object appeared; choice of the novel object was rewarded. In the standard task, the reward was in a well beneath the stimulus. In the verbal-reward condition the reward was not a separate object but was praise and applause. In the Velcro condition, the reward, although a separate and separable object, was attached to the base of the stimulus. Most infants at both ages succeeded in the verbal-reward and Velcro conditions but not in the standard condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Aspects of interpersonal, personality, and cognitive models of depression were tested in a college sample. The perceptions and actual interpersonal behaviors of dependent and self-critical women and their romantic partners were assessed during a conflict-resolution task. Dependent women were characterized by positive biases in the perception of lovingness expressed within the relationship. The partners of dependent women, however, experienced a decrease in positive affect and a trend toward increasing hostility during the conflict-resolution task. Self-critical women were objectively rated as less loving and more hostile, and their partners were also rated as less loving. Self-critics also exhibited negative biases in self-perceptions of submissiveness. The results are interpreted within a comprehensive framework integrating various elements of interpersonal, personality, and cognitive models of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Research to date suggests that the family plays a significant role in the development, perpetuation, and relapse of depression in its members. This study examined the videotaped interactions of parents with a depressed adolescent and control parents and youth during a conflictual, problem-solving task. In comparison with parents of nondepressed adolescents, parents of depressed adolescents engaged in higher rates of incongruent communication in which aversive content behavior was linked with positive affective behavior. Adolescent depressed content behavior led to greater suppression of parent aversive content behavior in nondepressed families than in depressed families. The findings argue that dysfunctional family communication may be associated with the development or maintenance of depression in the child. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
The day-night task requires saying "night" to a picture of the sun and "day" to a picture of the moon. In this investigation of why young children fail at this task, systematic variations of the task were administered to 96 children, half 4 years old and half 4 1/2 years old. Training children on the strategy of chunking the 2 rules into 1 ("say the opposite"), thus reducing memory load, did not help their performance. What helped was reducing the inhibitory demand by instructing them to say "dog" and "pig" (not "night" and "day") even though memory of 2 rules and inhibiting saying what the pictures represented were still required. Here the response to be activated and the response to be inhibited were unrelated. When the correct response was semantically related to, and the direct opposite of, the to-be-inhibited response, children performed poorly. Inserting a delay between stimulus and response helped even though that delay was filled with distraction. Young children apparently need several seconds to compute the answer on this task. Often they do not take the needed time; when forced to do so, they do well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
The copper-catalyzed aziridination of styrene with copper-exchanged zeolite HY (CuHY) and copper(II) triflate (trifluoromethanesulfonate) (Cu(OTf)2) as catalysts is described using N-(p-tolylsulfonyl)imino]phenyliodinane (PhI=NTs) as the nitrene donor. The effects on the ee and yield of the aziridine when the catalyst is modified by the presence of a chiral bis(oxazoline) are investigated in detail. The heterogeneously catalyzed reaction under these conditions shows a slight, but significant, enhancement in ee with increasing conversion at 25 °C. This is not observed in the more rapid homogeneously catalyzed reaction under identical reaction conditions using PhINTs as the nitrene donor. The enhancement in ee is proposed to result from the preferential reaction of the (S)-aziridine with the Cu2+:bis(oxazoline) complex in the presence of PhI=NTs, leading to an enhancement of the (R)-aziridine in the remaining aziridine product.  相似文献   
99.
100.
Radiotherapy plays an important role in the treatment of skin tumours. For skin carcinomas, external irradiation (kilovoltage X-rays or electrons according to clinical characteristics) is more valuable than interstitial brachytherapy, which is recommended for tumours of the lip and of the nasal vestibule. In mycosis fungoides, total cutaneous electron beam radiation therapy is efficient for patients with limited superficial plaques. In the classical form of Kaposi's sarcoma, radiotherapy can achieve local control whereas it obtains good palliative results in the epidemic form.  相似文献   
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