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H D Huang

Publications and source records attributed to H D Huang.

5 recordsLinked to original sources
PubMed2003

Database of repetitive elements in complete genomes and data mining using transcription factor binding sites.

Approximately 43% of the human genome is occupied by repetitive elements. Even more, around 51% of the rice genome is occupied by repetitive elements. The analysis presented here indicates that repetitive elements in complete genomes may have been very important in the evolutionary genomics. In this study, a database, called the Repeat Sequence Database, is first designed and implemented to store complete and comprehensive repetitive sequences. See http://rsdb.csie.ncu.edu.tw for more information. The database contains direct, inverted and palindromic repetitive sequences, and each repetitive sequence has a variable length ranging from seven to many hundred nucleotides. The repetitive sequences in the database are explored using a mathematical algorithm to mine rules on how combinations of individual binding sites are distributed among repetitive sequences in the database. Combinations of transcription factor binding sites in the repetitive sequences are obtained and then data mining techniques are applied to mine association rules from these combinations. The discovered associations are further pruned to remove insignificant associations and obtain a set of associations. The mined association rules facilitate efforts to identify gene classes regulated by similar mechanisms and accurately predict regulatory elements. Experiments are performed on several genomes including C. elegans, human chromosome 22, and yeast.

Algorithms↗
PubMed1999

Effects of dexamethasone on intracellular Ca2+ in its sensitive cells from neonatal mouse hippocampus and cultured cortical neurogliocytes.

AIM: To investigate the effects of dexamethasone (Dex) on intracellular free calcium ([Ca2+]i) in the single neuron or neurogliocyte. METHODS: Neonatal mouse hippocampal cells (NMHC) and cultured cortical neurogliocytes (CCN) were loaded with Fura 2-AM. The [Ca2+]i was measured with AR-CM-MIC-cation measurement system. RESULTS: Most of freshly isolated NMHC exhibited a rapid and concentration-dependent [Ca2+]i increase after administration of Dex 40-200 mumol.L-1. Only 10% of NMHC showed their [Ca2+]i decreases in total 96 tested cells. Dex-triggered [Ca2+]i rise was prevented by incubating the cells with Mg(2+)-free solution and reduced by adding LaCl3. Suspended NMHC in Ca(2+)-free solution or pretreated cells with mifepristone or tetrodotoxin prevented the initial [Ca2+]i increases caused by Dex 40-90 mumol.L-1, but only diminished the later [Ca2+]i rises by Dex 200 mumol.L-1. About 50% of tested single CCN showed a rapid and concentration-related [Ca2+]i increase due to Dex 90-270 mumol.L-1 exposure. This effect was partially inhibited under extracellular Ca(2+)- or Mg(2+)-free and mifepristone pretreatment conditions. CONCLUSION: Dex produces the rapid [Ca2+]i changes in both neurons and glia cells. Reactions among most cells include a Mg(2+)-dependent and glucocorticoid receptor-related extracellular Ca2+ influx and a high concentration of Dex-mediated intracellular Ca2+ release.

Animals↗
PubMed1990

S100 protein-positive dendritic cells and the significance of their density in gastric precancerous lesions.

Quantitative analysis of dendritic cells (DC's) was carried out in tissue specimens of normal gastric mucosa (n = 15), gastric ulcer (n = 19), chronic atrophic gastritis (n = 28), and gastric carcinoma (n = 65) by ABC immunostaining with S100 protein antibody. Significant increases in DC number were observed in chronic atrophic gastritis with type III intestinal metaplasia and/or grade II, III dysplasia. The result suggests that DC's are potentially capable of presenting neoantigens associated with malignant transformation at the precancerous stage when malignant morphological changes have not yet taken place. Combined with routine diagnostic methods, the serial monitoring of DC density in gastric mucosa may be useful in the follow-up of premalignant lesions in the stomach and the diagnosis of early gastric carcinoma.

Antibodies↗
PubMed1989

[Duodenal ulcer and the insulin releasing level].

Indirect pieces of evidences indicate the correlation between insulin level and pathogenesis of peptic ulcer. In the present study, serum insulin releasing level after glucose loading was determined in 16 patients with duodenal ulcer (DU) using radioimmunoassay, and was compared with that of normal controls. The peak insulin level (PIL) in DU patients was significantly higher than that of normal individuals (P less than 0.05), the measurements of gastric acidity, insulin level and the gastroscopic examination were carried out both before and after the treatment. The rebound phenomenon of gastric acidity (BAO) was correlated to that of PIL (r = 0.85). The possible relationship between insulin level and DU was discussed.

Adult↗