Search PubMed⌕ Search

Biomedical subjects

D Yao

Publications and source records attributed to D Yao.

62 records · Page 4Linked to original sources
PubMed1987

[3H]TCP binding sites in Alzheimer's disease.

Quantitative autoradiography was used to determine the density and distribution of [3H]1-[1-(2-thienyl)-cyclohexyl]piperidine ([3H]TCP) binding sites in human hippocampal tissue sections from control and Alzheimer's disease patients. Some Alzheimer's cases showed no changes in binding site density while other cases showed substantial declines in the CA1 region. [3H]TCP binding in the CA1 region from Alzheimer's patients was reduced an average of 40% while the other hippocampal regions were unaffected. It is proposed that the loss of [3H]TCP sites in the hippocampal CA1 region of certain Alzheimer's cases is associated with the greater cell loss observed in cases of severe Alzheimer's disease.

Alzheimer Disease↗
PubMed1986

Antigenic changes in gp70 associated with the adult variant of Gross murine leukemia virus, WB91.

Gross murine leukemia virus (GV) is not leukemogenic in adult mice whereas a variant of GV, WB91, is highly leukemogenic regardless of the age of the inoculated animal. FACS and SDS-PAGE analysis have demonstrated that these viruses differ at least with respect to the env-encoded gp70 molecule. FACS analysis of virus infected or virus transformed cells with a type specific monoclonal antibody (mAb #55) indicated a difference in determinants associated with gp70 expressed by the two viruses. Rat antisera raised against GV- or WB91-induced tumor cells demonstrated that there were no crossreactive determinants between the gp70 molecules expressed on these tumor cells as recognized by the rat antisera. This difference in the gp70 molecules encoded by WB91 and GV may account for the ability of the WB91 virus to induce leukemia in adult mice, possibly by affecting the immunogenicity of the virus.

AKR murine leukemia virus↗
PubMed1985

L-[3H]Glutamate binds to kainate-, NMDA- and AMPA-sensitive binding sites: an autoradiographic analysis.

The anatomical distribution of L-[3H]glutamate binding sites was determined in the presence of various glutamate analogues using quantitative autoradiography. The binding of L-[3H]glutamate is accounted for by the presence of 3 distinct binding sites when measured in the absence of Ca2+, Cl- and Na+ ions. The anatomical distribution and pharmacological specificity of these binding sites correspond to that reported for the 3 excitatory amino acid binding sites selectively labelled by D-[3H]2-amino-5-phosphonopentanoate (D-[3H]AP5), [3H]kainate ([3H]KA) and [3H] alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid ([3H]AMPA) which are thought to be selective ligands for the N-methyl-D-aspartate (NMDA), KA and quisqualate (QA) receptors, respectively.

Animals↗
PubMed1984

Autoradiography of D-2-[3H]amino-5-phosphonopentanoate binding sites in rat brain.

Quantitative autoradiographic techniques were used to obtain a preliminary description of the pharmacological characteristics and anatomical distribution of the selective N-methyl-D-aspartate (NMDA) receptor antagonist D-2-[3H]amino-5-phosphonopentanoate (D-[3H]AP5). Binding sites exhibit the appropriate pharmacological profile and are found throughout the brain. Consistent with ligand binding experiments using purified synaptic membranes, the hippocampus has the highest levels of binding. Within this structure, the binding site distribution is indistinguishable from that obtained for D-AP5-sensitive L-[3H]glutamate binding sites; highest levels are found within the stratum radiatum, a region in which NMDA receptors are involved in the formation of long-term potentiation.

2-Amino-5-phosphonovalerate↗
PubMed1984

Distribution of [3H]AMPA binding sites in rat brain as determined by quantitative autoradiography.

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) is a potent neuroexcitatory compound which acts at the quisqualate class of excitatory amino acid receptors. In this study we describe the pharmacological characteristics and anatomical distribution of [3H]AMPA binding sites in rat brain using quantitative autoradiography. These binding sites exhibit the appropriate pharmacological characteristics and are found in high concentrations in the hippocampus, cerebral cortex (especially layers I-III), induseum griseum, and dorsal lateral septum. Intermediate concentrations are found in the corpus striatum and deeper layers of cerebral cortex. Lower concentrations are found in the diencephalon, midbrain and brainstem. These results demonstrate that [3H]AMPA binding sites are found throughout the CNS and suggest brain regions which may use quisqualate receptors as glutamate neurotransmitter receptors.

Animals↗
PubMedDate not supplied

Do arterial phase helical CT images improve detection or characterization of colorectal liver metastases?

Our goal was to determine if arterial phase images from dual phase helical CT improve either the detection or the characterization of hepatic metastases in patients with colorectal carcinoma. Sixty-two patients with known colorectal cancer underwent 65 dual phase helical CT examinations to evaluate for possible liver metastases. Three blinded reviewers independently evaluated the portal venous phase images alone to determine if hepatic metastases were present or absent. Arterial phase images were then analyzed to determine if they identified additional lesions or aided in characterizing small hepatic lesions. Scores of the two methods for diagnosing metastases were compared with the "gold standard" established by a consensus panel of three other radiologists who reviewed all images together with clinical, pathologic, and other imaging data. The addition of arterial phase imaging did not detect any new metastases. However, in 6 of the 64 technically adequate examinations, hepatic arterial phase images increased lesion conspicuity and significantly increased diagnostic confidence when compared with portal vein phase scans alone. In patients with colorectal cancer, the addition of arterial phase imaging does not increase sensitivity, but improves the specificity in diagnosing liver metastases in a small number of cases. Dual phase helical CT does not appear to be indicated in the evaluation of liver metastases from colorectal cancer.

Adult↗