Biomedical subjects

B C Chu

Publications and source records attributed to B C Chu.

39 records · Page 3Linked to original sources

PubMedDate not supplied

Presentation of ligands on hydroxylapatite.

Conjugates of biotin with the decamer of glutamic acid (glu10) and the trimer of D,L-2-amino-5-phosphonovaleric acid (I) have been synthesized, and it has been shown that they mediate the binding of avidin to hydroxylapatite. In a similar way a conjugate of methotrexate with glu10 mediates the binding of dihydrofolate reducatase to the mineral. The presentation of ligands on the hydroxylapatite component of bone may find applications in clinical medicine.

2-Amino-5-phosphonovalerate↗

PubMedDate not supplied

A simple procedure for cross-linking complementary oligonucleotides.

A simple, efficient procedure for cross-linking two complementary oligonucleotides, which does not require chemical modification of either oligonucleotide, is described. One of the oligonucleotides is first converted to the 5'-phosphorothioate derivative with polynucleotide kinase. It is then incubated with its complement in the presence of 1 microM trans-platinum(II)diammine dichloride. After overnight incubation, 40-50% cross-linking is observed. DNA synthesis by the Klenow fragment of Escherichia coli DNA polymerase I is blocked at the cross-linked site, resulting in the formation of truncated products. Potassium platinous chloride (K2PtCl4) and cis-platinum(II)diammine dichloride form cross-links less efficiently than the trans isomer.

Base Sequence↗

PubMedDate not supplied

Flow volume in the common carotid artery detected by color duplex sonography: an approach to the normal value and predictability of cerebral blood flow.

PURPOSE: To determine normal common carotid artery (CCA) flow volume, its relationship with age, and the predictability of cerebral blood flow (CBF) by color duplex sonography. SUBJECTS AND METHODS: Forty-five healthy subjects (18 men, 27 women, 23-86 years old) and 13 patients (3 men, 10 women, 51-88 years old) without neurological disease underwent color duplex sonography. All 13 patients also underwent xenon CT. CCA flow volume in the healthy subjects was measured to determine normal values. This volume was divided by mean brain weight to estimate CBF, which was correlated with CBF measured by xenon CT in regions of ipsilateral internal carotid arteries (ICA). RESULTS: In healthy subjects, CCA flow volume ranged from 155.0-458.8 ml/min (mean+/-SD: 267.77+/-59.91), corresponding to an estimated CBF of 12.43-32.84 ml/min/100 g brain weight (mean+/-SD: 20.63+/-4.22). No relationship was found between flow volume and age. A good correlation was found between estimated CBF and CBF measured by xenon CT in regions of both ICAs (gamma=0.713, p=0.0062 on the left; gamma=0.686, p=0.0096 on the right). CONCLUSION: By using color duplex sonography, we established a set of normal CCA flow volumes, which do not decline with age. Estimated CBF derived from flow volume can predict actual CBF.

Adult↗