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D Denney

Publications and source records attributed to D Denney.

15 recordsLinked to original sources
PubMed1990

Subtractive hybridization system using single-stranded phagemids with directional inserts.

We describe a subtractive hybridization protocol which is designed to permit subtractions between cDNA libraries. The method uses single-stranded phagemids with directional inserts as both the driver and the target. We modified the M13 phagemid vector pBluescript for the directional cDNA cloning and subtractive hybridization. Two simplified methods for efficient construction of directional cDNA libraries are also described. Using a model system, we found that one round of subtractive hybridization results in a 5,000-fold specific subtraction of abundant molecules. We used two methods to quantify the efficiency and verify the specificity of the subtraction. In order to obtain these subtraction efficiencies, it was necessary to develop a method to purify the single-stranded DNA to homogeneity. The single-stranded purification involved using potassium iodide (KI) density centrifugation, restriction endonuclease digestion and phenol extraction in the presence of magnesium. We describe the several advantages of using directional inserts for the subtraction procedure.

Bacteriophages↗
PubMed1987

Molecular mapping of class II polymorphisms in the human major histocompatibility complex. I. DR beta.

We have studied 27 cell lines homozygous by consanguinity for the major histocompatibility complex to establish the restriction fragment length polymorphism (RFLP) patterns seen with six different restriction enzymes (Bam HI, Bg1 II, Eco RI, Hinc II, Hind III, Pvu II) and DR beta chain probes. The probes used were a full-length cDNA DR beta probe and a probe specific for the 3' untranslated region. The RFLP obtained represent the first standard patterns for the individual haplotypes DR1 through 7 and DR9 as defined by genetically homozygous lines. The patterns obtained reflect the DR specificities closely, as well as the DRw52 and DRw53 specificities. These latter specificities are associated with the most prominent patterns of RFLP. Bands are present which are unique for the haplotypes DR1, DR2, DR4, DR7, DRw52, and DRw53, and could be used for typing these haplotypes in heterozygotes. Subtypes can be identified for all of the haplotypes except DR1. These subtypes indicate that there is an extensive amount of polymorphism in the DR subregion that has not been identified serologically.

Cell Line↗
PubMed1987

Molecular mapping class II polymorphisms in the human major histocompatibility complex. II. DQ beta.

The restriction fragment length polymorphisms have been determined for six restriction enzymes (Bam HI, Bg1 II, Eco RI, Hinc II, Hind III, and Pvu II) and a DQ beta probe on 25 cell lines that are homozygous by consanguinuity at the MHC. These patterns reflect both DR haplotypes and DQ types of the cells tested. At least one non-polymorphic band is present in all the cell lines with every restriction enzyme except Hinc II. This band most probably represents DX beta hybridization. The polymorphic bands indicate that more polymorphism exists in the DQ subregion than is predicted serologically. Each DR haplotype is associated with a unique set of restriction fragments except for DR2 and DR6. The patterns are largely consistent within each DR haplotype. In addition, some bands reflect the established DQ specificities DQw1 and DQw2. Individual bands can be identified that are unique to the haplotypes DR1, DR4, DR5, and DR6 and the DQw1- and DQw2-associated haplotypes. Subdivisions of haplotypes can be identified with this probe. In particular, MVL (DR1), Akiba (DR2), QBL (DR3), FPF (DR5), and APD (DR6) have polymorphisms that distinguish them from other members of their DR haplotype.

Cell Line↗
PubMed1987

Allelic variation in the DR subregion of the human major histocompatibility complex.

Allelic variation in the DR subregion of the human major histocompatibility complex has been analyzed by nucleic acid sequencing of cDNA clones obtained from cell lines homozygous by consanguinity for all the common serological types DR1-9. Two expressed loci were identified in the haplotypes DR2, -3, -4, -7, and -9; one locus being present at a much lower frequency (4-7%) than the other. The low-frequency allele was highly conserved between each of the DRw53 (DR4, -7, -9) and the DRw52 (DR3, -5, -6) haplotypes. Analysis of the variation between alleles confirms the presence of three allelic hypervariable regions. At each variable residue, a limited range of amino acid substitutions are found, distinguishing them from immunoglobulin hypervariable regions. Dinucleotide substitutions are extremely common. Individual hypervariable regions are often shared between haplotypes. Much of the variation in these alleles can be attributed to the shuffling of these regions between haplotypes, possibly by the mechanism of gene conversion.

Alleles↗
PubMed1979

Telemetered EEG-EOG during psychotic behaviors of schizophrenia.

In an effort to establish correlations between abnormal behaviors characteristic of schizophrenia and simultaneous cerebral electrical activity, EEGs and electro-oculograms (EOGs) were continuously recorded for 2 to 24 hours by radiotelemetry from 40 patients with schizophrenia and 12 normal control subjects. Trained observers recorded specific behavior patterns permitting visual and computer analysis of EEG during hallucinations, stereotypy, catatonia, psychomotor blocking, and other characteristic manifestations of schizophrenia. Electroencephalographic abnormalities consisting of focal slow or spike activity over either temporal region were found in nearly half of the patients so recorded. In contrast to the EEG during ictal episodes of epilepsy, the abnormal wave forms of schizophrenic patients seldom coincided with episodes of blocking, stereotypy, or other abnormal behaviors. Increased extraocular activity or blinking were recorded in a majority of patients, but were not consistently associated with the abnormal behavior or perceptual events.

Adult↗
PubMed1977

Pharmacological characterization of tardive dyskinesia.

Tardive dyskinesia (TD) may be a clinical manifestation of a relative imbalance between the inversely related dopaminergic (DA) and acetylcholinergic (ACh) influences in the central nervous system (CNS). Six patients were evaluated with single challenge doses of a DA agonist, levodopa, and antagonist, droperidol, as well as with an ACh agonist, physostigmine, an antagonist, benztropine, and a placebo. A single blind trial with deanol and placebo followed. Responses, measured by an electrophysiological technique, formed two subgroups. The patients who improved with a DA antagonist or an ACh agonist improved while taking deanol. Another group of patients were made worse with a DA antagonist or ACh agonist and were worsened or had no response while taking deanol. While the results add support to the concept of counterbalancing DA-ACh influences in TD, further investigation of TD subtypes and predictors of drug response is warranted.

Adult↗