Biomedical subjects

Di Wang

Publications and source records attributed to Di Wang.

24 records · Page 2Linked to original sources

PubMed2004

[Expression of nuclear factor kappaB and the effect of topical tacrolimus ointment on lesional atopic dermatitis skin].

OBJECTIVE: To investigate the role of nuclear factor kappaB (Rel/NF-kappaB) in pathogenesis of atopic dermatitis(AD) and the effect of topical 0.1%(mass fraction) or 0.03%(mass fraction) tacrolimus ointment on expression of NF-kappaB in lesional AD skin. METHODS: Immunohistochemistry has been employed to study the expression of NF-kappaB in normal skin and lesional AD skin before and after using topical tacrolimus ointment. RESULTS: The expressions of NF-kappaBp50 and NF-kappaBp65 were scattering or negative in normal keratinocytes. NF-kappaBp50 was overexpressed on nuclear of basal and suprabasal keratinocytes in 9 cases of AD, NF-kappaBp65 was overexpressed in cytoplasm and perinuclear of basal and suprabasal keratinocytes. After using topical tacrolimus ointment for three weeks , nuclear NF-kappaBp50 expressed on basal and suprabasal keratinocytes were lost and NF-kappaBp50 was expressed sparsely on basal keratinocytes cytoplasm or nuclear. NF-kappaBp65 was expressed sparsely on basal and suprabasal keratinocytes cytoplasm. CONCLUSION: These data suggest that increased NF-kappaB activity may represent the basis of initiation or maintenance of the skin inflammatory response in atopic dermatitis. Topical tacrolimus may directly or indirectly inhibit NF-kappaB nuclear expression in keratinocytes and inhibit skin innate immuno-inflammatory response in atopic dermatitis that related to NF-kappaB.

Administration, Cutaneous↗

PubMed2003

Regio- and stereoselective homolytic hydrostannylation of propargyl alcohols and ethers with dibutylchlorostannane.

The Et3B-initiated reaction of gamma-unsubstituted propargyl alcohols with dibutylchlorostannane (Bu2SnClH) at low temperature gave (Z)-vinylstannanes with high regio- and stereoselectivity. The corresponding alkyl propargyl ethers also underwent regio- and stereoselective homolytic hydrostannylation with Bu2SnClH; however, the regioselectivity was not so high as that with the propargyl alcohols.

Journal Article↗

PubMed2003

Binary neural network training algorithms based on linear sequential learning.

A key problem in Binary Neural Network learning is to decide bigger linear separable subsets. In this paper we prove some lemmas about linear separability. Based on these lemmas, we propose Multi-Core Learning (MCL) and Multi-Core Expand-and-Truncate Learning (MCETL) algorithms to construct Binary Neural Networks. We conclude that MCL and MCETL simplify the equations to compute weights and thresholds, and they result in the construction of simpler hidden layer. Examples are given to demonstrate these conclusions.

Algorithms↗

PubMed2003

Comparative study on apoptosis induction of SMMC7721 and Vero cells by Clostridium difficile toxin A.

BACKGROUND & OBJECTIVE: Clostridium difficile is recognized as a frequent cause of antibiotic-induced diarrhea. This study was designed to investigate whether Clostridium difficile toxin A might induce apoptosis on human hepatoma cell line SMMC7721 and African green monkey kidney Vero cells. METHODS: Highly purified toxin A was obtained by bovine thyroglobulin affinity purification followed by ion exchange chromatography on Q sepharose. The apoptosis induction of toxin A was examined on SMMC7721 cells with Vero cells as a control. Inhibition of proliferation was measured by MTT assay. Morphological assessment of apoptosis was performed with fluorescence and electronic microscopy. DNA fragmentation was observed by agarose gel electrophoresis. Cell cycle distribution was analyzed by flow cytometry. RESULTS: Toxin A (0.293-4.690 mg x L(-1) ) inhibited proliferation of SMMC7721 and Vero cells in a time- and concentration-dependent manner. Morphological changes of typical apoptosis showed that SMMC7721 had a higher percentage of apoptosis than Vero cells. Agarose gel electrophoresis of DNA from SMMC7721 treated with toxin A for 48 hours revealed a "ladder" pattern. CONCLUSION: Clostridium difficile toxin A induced apoptosis of SMMC7721 and Vero cells. The apoptosis induction on SMMC7721 cells was more effective than that on Vero cells.

Animals↗

PubMed2002

Effect of bax, bcl-2 and bcl-xL on regulating apoptosis in tissues of normal liver and hepatocellular carcinoma.

AIM: To investigate the expression of bax, bcl-2 and bcl-xL mRNA in the tissues of normal liver and hepatocellular carcinoma (HCC), and analyze the relationship between the expression of bax, bcl-2 and bcl-xL mRNA and clinical parameters of HCC patients. METHODS: The expression of bax, bcl-2 and bcl-xL mRNA of normal liver and HCC was measured by Northern blot. Statistical analyses were made by t test and correlation analysis. RESULTS: A very low mRNA level was indicated at bax, bcl-2 and bcl-xL in the HCC tissues in contrast to the tissues of normal liver by Northern blot analysis. The analyses of mRNA level revealed that HCC tissues exhibited a mean 7.6-fold decrease in bax, 4.2-fold in bcl-2 and 3.5-fold in bcl-xL in comparison with normal control tissues, respectively. Positive correlation was found between bax and bcl-xL (r=0.7061, P<0.01). There was no significance between the mRNA expression of these three genes and age, gender, tumor differentiation and tumor stage of HCC patients. CONCLUSION: The results are consistent with the fact that apoptosis rarely occurs in normal livers but increases in HCC, indicating that bcl-2 and bcl-xL may play a very important role in regulating the apoptosis of normal liver and HCC.

Adult↗

PubMed2002

The cognitive demands of an innovative query user interface.

Too often, online searches for health information are time consuming and produce results that are not sufficiently precise to answer clinicians' or patients' questions. The PERSIVAL project is designed to circumvent this problem by personalizing and tailoring searches and presentation to the demands of the user and the particular clinical context. This paper focuses on a cognitive evaluation of one component of this project, a Query User Interface (QUI). The study examines the system's ability to allow users to easily and intuitively express their information needs. We performed several analyses including a cognitive walkthrough of the interface and quantitative estimations of cognitive load. The paper also presents a preliminary analysis of usability testing. The analyses suggest that there are features in the QUI that contribute to a greater cognitive load and result in greater effort on the part of the subject. The results of usability testing are consistent with these findings. However, subjects found it to be relatively easy and intuitive to generate well-formed queries using the interface. This study contributed to the iterative design of the interface and to the next generation of the PERSIVAL system.

Attitude to Computers↗