Search PubMed⌕ Search

Biomedical subjects

Yuan Jiang

Publications and source records attributed to Yuan Jiang.

25 records · Page 2Linked to original sources

Mutation of melanosome protein RAB38 in chocolate mice.

Mutations of genes needed for melanocyte function can result in oculocutaneous albinism. Examination of similarities in human gene expression patterns by using microarray analysis reveals that RAB38, a small GTP binding protein, demonstrates a similar expression profile to melanocytic genes. Comparative genomic analysis localizes human RAB38 to the mouse chocolate (cht) locus. A G146T mutation occurs in the conserved GTP binding domain of RAB38 in cht mice. Rab38(cht)/Rab38(cht) mice exhibit a brown coat similar in color to mice with a mutation in tyrosinase-related protein 1 (Tyrp1), a mouse model for oculocutaneous albinism. The targeting of TYRP1 protein to the melanosome is impaired in Rab38(cht)/Rab38(cht) melanocytes. These observations, and the fact that green fluorescent protein-tagged RAB38 colocalizes with end-stage melanosomes in wild-type melanocytes, suggest that RAB38 plays a role in the sorting of TYRP1. This study demonstrates the utility of expression profile analysis to identify mammalian disease genes.

Animals↗

Lung cancer cell identification based on artificial neural network ensembles.

An artificial neural network ensemble is a learning paradigm where several artificial neural networks are jointly used to solve a problem. In this paper, an automatic pathological diagnosis procedure named Neural Ensemble-based Detection (NED) is proposed, which utilizes an artificial neural network ensemble to identify lung cancer cells in the images of the specimens of needle biopsies obtained from the bodies of the subjects to be diagnosed. The ensemble is built on a two-level ensemble architecture. The first-level ensemble is used to judge whether a cell is normal with high confidence where each individual network has only two outputs respectively normal cell or cancer cell. The predictions of those individual networks are combined by a novel method presented in this paper, i.e. full voting which judges a cell to be normal only when all the individual networks judge it is normal. The second-level ensemble is used to deal with the cells that are judged as cancer cells by the first-level ensemble, where each individual network has five outputs respectively adenocarcinoma, squamous cell carcinoma, small cell carcinoma, large cell carcinoma, and normal, among which the former four are different types of lung cancer cells. The predictions of those individual networks are combined by a prevailing method, i.e. plurality voting. Through adopting those techniques, NED achieves not only a high rate of overall identification, but also a low rate of false negative identification, i.e. a low rate of judging cancer cells to be normal ones, which is important in saving lives due to reducing missing diagnoses of cancer patients.

Adenocarcinoma↗

Wnt5a signaling directly affects cell motility and invasion of metastatic melanoma.

Gene expression profiling identified human melanoma cells demonstrating increased cell motility and invasiveness. The gene WNT5A best determined in vitro invasive behavior. Melanoma cells were transfected with vectors constitutively overexpressing Wnt5a. Consistent changes included actin reorganization and increased cell adhesion. No increase in beta-catenin expression or nuclear translocation was observed. There was, however, a dramatic increase in activated PKC. In direct correlation with Wnt5a expression and PKC activation, there was an increase in melanoma cell invasion. Blocking this pathway using antibodies to Frizzled-5, the receptor for Wnt5a, inhibited PKC activity and cellular invasion. Furthermore, Wnt5a expression in human melanoma biopsies directly correlated to increasing tumor grade. These observations support a role for Wnt5a in human melanoma progression.

Actins↗

[Landscape structure of the farming-pastoral zone based on Landsat-TM data--a case study of Xinghe County, Inner Mongolia].

Xinghe County, Inner Mongolia, belongs to the typical region of farming-pastoral zone in northern China and is chosen as a case study area in this paper. Based on the interpretation of the Landsat-TM data (with two digital images taken in 1989 and 2000, respectively), the landscape structure was studied by analyzing patch-size, spatial pattern, and other index to show the changing feature of landscape pattern. The results showed that farmlands and grasslands were the main landscape types in plain and hilly land of the County, and different landscape types had different scales of landscape patch-size. The patch-sizes of farmland and grassland had been apparently expanded from 1989 to 2000, while those of the forestland and waters had been shrunk. The landscape pattern had an obvious trend of fragmentation due to human activities.

Agriculture↗

Determination of chloramphenicol in royal jelly by liquid chromatography/tandem mass spectrometry.

A liquid chromatographic/tandem mass spectrometric method was developed and validated for the determination of chloramphenicol (CAP) in royal jelly. Royal jelly samples were first denatured with lead acetate solution, and the CAP was extracted with solid-phase extraction before separation by liquid chromatography. A triple-quadrupole mass spectrometer operated in the negative electrospray ionization and selected-reaction monitoring mode was used for the detection of CAP. For method validation, royal jelly samples were fortified at CAP levels between 0.1 and 10.0 microg/kg; at these levels, recovery values (internal standard-corrected) ranged from 93.3 to 105.0%, and the within-laboratory reproducibility (relative standard deviation) was < or = 9.1%. The decision limit was 0.07 microg/kg, and the detection capability was 0.1 microg/kg.

Anti-Bacterial Agents↗