PubMed Health⌕ Search

Biomedical subjects

J M Andrew

Publications and source records attributed to J M Andrew.

15 recordsLinked to original sources
PubMed1994

Isolation and characterization of libraries of monoclonal antibodies directed against various forms of tubulin in Paramecium.

Ciliates are very good models for studying post-translationally generated tubulin heterogeneity because they exhibit highly differentiated microtubular networks in combination with reduced genetic diversity. We have approached the analysis of tubulin heterogeneity in Paramecium through extensive isolation and characterization of monoclonal antibodies using various antigens and several immunization protocols. Eight monoclonal antibodies and 10 hybridoma supernatants were characterized by: i) immunoblotting on ciliate and pig brain tubulins as well as on peptide maps of Paramecium axonemal tubulin; ii) immunoblotting on ciliate tubulin fusion peptides generated in E coli, a procedure which allows in principle to discriminate antibodies that are directed against tubulin sequence (reactive on fusion peptides) from those directed against a post-translational epitope (non-reactive); and iii) immunofluorescence on Paramecium, 3T3 and PtK2 cells. Twelve antibodies labeled all microtubules in Paramecium cells and were found to be directed against tubulin primary sequences (nine of them being located in the alpha N-terminal domain, one in the beta C-terminal one, and two in alpha and beta central stretches). The remaining ones decorated only a specific subset of microtubules within the cell and were presumably directed against post-translational modifications. Among these, three antibodies are directed against an N-terminal acetylated epitope of alpha-tubulin whereas the epitopes of three other ones (TAP 952 degrees, AXO 58 and AXO 49 degrees) apparently correspond to still unidentified post-translational modifications, located in the C-terminal domain of both alpha- and beta-tubulins. The AXO 49 degrees specificity is similar to that of a previously described polyclonal serum raised against Paramecium axonemal tubulin [2]. The results are discussed in terms of identification and accessibility of the epitopes and immunogenicity of ciliate tubulin with reference to mammalian and ciliate tubulin sequences.

Amino Acid Sequence↗
PubMed1991

Expression of the CDw75 (beta-galactoside alpha 2,6-sialyltransferase) antigen on normal blood cells and in B-cell chronic lymphocytic leukaemia.

Using monoclonal antibodies (mAb) characterized at the last International Workshop on Human Leucocyte Antigens, we examined the expression of CDw75 antigens (beta-galactoside alpha 2,6-sialyltransferase) on normal peripheral blood cells and on cells from patients with B-cell chronic lymphocytic leukaemia (CLL). The mAb used (HH2, EBU.65, EBU.141 and OKB4) detect different epitopes of CDw75. Normal peripheral blood B cells expressed high levels of CDw75 detectable with HH2, EBU.65 and EBU.141 but did not react with OKB4. Cells from patients with B-cell CLL closely resembled normal B cells. All CDw75 epitopes, including OKB4, were strongly expressed on some Namalwa variant Burkitt lymphoma cell lines. The OKB4 epitope was also present on red cells from all normal donors. The other CDw75 mAb were unreactive with red cells from some normal donors. The CDw75 epitope detected with EBU.65 was present on most CD4+ T cells and on a minority of CD8+ cells. HH2 and EBU.141 stained only small numbers of T lymphocytes. OKB4 did not react with T cells. EBU.65+, CD4+ T cells had low levels of expression of CD45R0, CD29, CD54 and CD58, and had high levels of CD45RA antigen. Phytohaemagglutinin (PHA) activation of cells led to the loss of EBU.65 binding. These results suggest that the CDw75 epitope recognized by the EBU.65 mAb is a marker of native T lymphocytes. On B CLL cells the epitopes detected with HH2, EBU.65 and EBU.141 were destroyed by treatment with neuraminidase. Treatment of B-CLL cells and red cells with neuraminidase increased the binding of OKB4, suggesting that this epitope is masked by sialic acid. The results suggest that CDw75 is a sialylated cell-surface antigen expressed in a number of tissue-specific isoforms.

Antigens, CD↗
PubMed1981

Imbalance on the Weights Test and violence among delinquents.

This study forms part of a continuing series investigating the correlates of violent crime. The Weight Test, a measure of proprioceptive cognition, was administered to 41 community-retained Caucasian juvenile and adult male legal offenders whose offenses were rated for violence by the Violence Scale. As hypothesized, the Weight Test results were related to Violence Scale scores. Within four age ranges, offenders whose Weights Test scores suggested mild impairment, also had committed more violent offenses, in comparison with a combined group of those whose Weights scores suggested either: (a) no impairment or (b) moderate impairment. Reasons for the greater violence of the mildly impaired were sought within other studies of proprioceptive function as it relates to psychological disorder.

Adolescent↗
PubMed1981

Parietal laterality and violence.

To test whether laterality of parietal lobe cerebral functioning might relate to a history of violent behavior, a sample of 33 male and female, right-handed juvenile offenders, divided into less and more violent, each performed the Weighs Test. A lateralization index (left-hand score divided by right-hand score) formed the dependent variable. Differences for sexes and ages, but not ethnicities, required corrections. As hypothesized, poorer right- than left-parietal function related positively with the violence of past crimes. A sample of 18 additional subjects replicated the findings. The results were discussed in terms of a concept of cerebral "area-appropriateness," so that when the task-appropriate area performs less well than a less-appropriate area, we may begin to infer a dysfunction which may relate to "dyscontrol" and to violent behavior.

Adolescent↗
PubMed1981

"Optimal" lateralization on the Tapping Test.

The present study was designed to test the general "imbalance" hypothesis in regard to the Tapping Test, a motor measure of finger-oscillation speed from the Halstead-Reitan neuropsychological battery. The study was prompted by a recent spate of reports linking cerebral lateralization to a variety of conditions. It was hypothesized that it would be possible to determine an "optimal," midrange of lateralization, to be identified by faster tapping speeds. As hypothesized, those offenders with "moderate" laterality achieved faster speeds than those with "extreme" laterality ("extreme" defined as either less or more laterality than for the moderates). The same range appeared optimal over several demographic groups. A second goal of the present study was to pursue hints from a previous study that had suggested a lateralization measure might prove to be free of some unwanted variations by demographics. As hypothesized, the lateralization measure appeared free of variations according to age, sex, and handedness. Applications and future directions were suggested.

Adolescent↗
PubMed1977

Delinquents and the Tapping Test.

This study provided Tapping Test norms for young legal offenders by measuring 54 Anglo male probationers (35 juveniles, 19 adults) in Study I, and 127 probationers aged 12-17 within eight sex/age/ethnicity subgroups in Study II. The Tapping Test, a measure of fine-motor speed, forms part of the Halstead-Reitan battery for neuropsychodiagnosis. Study I results suggest that tapping speed related to age for juvenile male delinquents, p less than .01; for adults, speed relates to IQ, p less than .05. Study II results suggest that Anglo females--but not non-Anglo females-- tap slower than males, p less than .01. The results were only paritally consistent with those of prior studies. Future researchers may wish to: (a) refine norms by appropriate adjustments for age and IQ; (b) investigate why Anglo female delinquents were especially slow on the Tapping Test; and (c) evaluate to what extent false positives may be provoked on this test by depression rather than organicity.

Adolescent↗
PubMedDate not supplied

Delay of surgery.

Explore the source record for details and available documents.

Adult↗