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Biomedical subjects

A Harris

Publications and source records attributed to A Harris.

At least 469 records · Page 26Linked to original sources
PubMed1984

A direct bone marrow chromosome technique for acute lymphoblastic leukemia.

We describe a direct bone marrow chromosome technique that was developed especially for use in studies of acute lymphoblastic leukemia (ALL). The features responsible for technical improvements include: the use of RPMI 1640 medium, supplemented with 30% fetal calf serum, to support cellular activity during both specimen transport and Colcemid treatment; the processing of only 0.1 ml of sedimented cells or less per centrifuge tube; the exposure of cells to Colcemid for a maximum of 25 min; control of the total time of exposure to hypotonic solution; the use of a steel wire as a stirring rod (fashioned to fit the centrifuge tube) for mixing cells; slide preparation by a specific edging-flaming technique; the natural aging of the slides to achieve optimal drying; and the use of a modified G-banding procedure that employs Wright's stain. This technique has been used in more than 350 cases of ALL and has consistently provided analyzable banded chromosomes, even in hyperdiploid cases with up to 91 chromosomes. It makes the previously recognized morphological difference between metaphases of residual normal cells and those from the leukemic clone less apparent. The edging-flaming technique of slide preparation is the most important component and is especially appropriate for spreading large numbers of chromosomes in ALL.

Bone Marrow↗
PubMed1984

Carcinoma of the cervical esophagus: diagnosis, management, and results.

Nine of 168 patients (5.3%) with carcinoma of the esophagus had primary tumors in the cervical esophagus. The principal symptoms and signs of carcinoma of the cervical esophagus were dysphagia, hoarseness, neck mass, and weight loss. The esophagogram was a very reliable study, revealing the abnormality in all nine patients. The true extent of the disease was better delineated by computerized tomography which demonstrated not only the intraluminal mass but also the extraesophageal spread. Endoscopic examination of the cervical esophagus was the definitive procedure to establish the diagnosis. All nine patients were treated with definitive radiotherapy, three surviving two to five years. The major cause of death was the failure to control local disease.

Carcinoma, Squamous Cell↗
PubMed1984

Molecular characterization of the Epstein-Barr virus DNA in three new Burkitt's lymphoma-derived cell lines.

Three new Epstein-Barr virus DNA populations have been isolated from the recently established Burkitt's lymphoma-derived cell lines, LY47, LY91 and BL8. Each of these lines carries one of the specific chromosome translocations associated with Burkitt's lymphoma but few if any other chromosomal abnormalities. An outline of their molecular organization, as determined by restriction enzyme analysis, is presented. Two of the isolates, LY47 and BL8, give patterns broadly similar to Epstein-Barr virus DNA molecules studied to date. The third, LY91, shows a highly unusual molecular organization, in particular within BamHI subfragments of the EcoRI A fragment, indicative of the presence of a major defective molecular species within this line. All three cell lines produce virions that are capable of transforming immature B-lymphocytes.

Burkitt Lymphoma↗
PubMed1983

Intracellular topography of immunoreactive gastrin demonstrated using electron immunocytochemistry.

Gastrin (G)-producing cells from the mammalian gastric antrum have been investigated using computer-assisted morphometry and a novel double colloidal gold-labeled-immunoglobulin electron immunocytochemical procedure. Correlation analysis of human antral G-cells indicates (p less than 0.001) that a single population of granules exists with small (160 nm) electron-dense and large (240 nm) electron-lucent forms representing the extremes. Non-crossreacting region-specific antisera have been used to visualize G-17 and G-34 (progastrin) to the small electron-dense granules and G-17 to the other intermediate forms. From the results we propose a topographic segregation of immunoreactive gastrins within 2 apparently distinct granule subclasses and suggest that this may represent the pathway of granule maturation.

Adult↗
PubMed1983

Cystic fibrosis: a detailed analysis of fibroblast membrane glycoproteins.

The binding properties of two lectins, concanavalin A and wheatgerm agglutinin to membrane glycoproteins extracted from cystic fibrosis fibroblasts have been examined. No differences were found between the binding patterns of either of these lectins to cystic fibrosis and normal fibroblast glycoproteins. The amount of concanavalin A binding to a glycoprotein of approximate Mr 150 000 has been shown to be related to the population doubling time of a cell culture at the time of analysis.

Adolescent↗
PubMed1983

Synthesis of exo-3-phenylbicyclo[3.2.1]oct-3-en-2-amine and related compounds as potential analgesics.

Several analogues (21 and 29-50) of exo-3-phenylbicyclo[3.2.1]oct-3-en-2-amine (1) were prepared, a compound that had been found to have marked antinociceptive activity in the inflamed-paw pressure test in rats. Two synthetically versatile methods leading to these compounds are described. In this series, antinociceptive activity increases with increasing size of the amine substituent, reaching an optimum with N(Me)Et (32), but this is always associated with central nervous system (CNS) stimulant activity. The antinociceptive activity of these compounds is most likely due to an action that is similar to that of amphetamine rather than to an interaction with an opiate receptor. The endo diastereoisomer 22 and the benzo analogue 11 were both devoid of antinociceptive and CNS stimulant activity.

Acetylcholine↗
PubMed1983

Chronic urticaria in childhood: natural course and etiology.

We retrospectively studied 94 children with urticaria longer than six weeks in duration. The disease was equally distributed among the sexes and the following age subgroups (0-3.9 years, 4.0-7.9 years, 8.0-11.9 years and 12.0-15.9 years). A cause of the urticaria was identified or suspected in 15 of the patients. These included eight patients with cold urticaria, two with infection (hepatitis, sinusitis), two with food allergy, one patient with juvenile rheumatoid arthritis, one with arthralgia associated with a positive ANA and one with a low level of total hemolytic complement (CH50). Follow-up of a year of more on 52 patients revealed a median duration of urticarial symptoms of 16.0 months, with 58% of children becoming symptom free for six months or more, whereas the remaining 42% continued to have recurrent symptoms but without the development of an underlying serious illness. Results of the present study indicate that the etiology of chronic urticaria in childhood remains mostly undetermined but that the prognosis is generally favorable. However, one must consider an underlying infection or autoimmune disease as a potential etiology.

Adolescent↗
PubMed1982

Glycoproteins that distinguish different cell types found in amniotic fluid.

Two concanavalin A-binding glycoproteins of approximate Mw 150 K and 140 K are described, which enable two of the main cell types found in amniotic fluid samples obtained by amniocentesis, AF and F cells, to be reliably distinguished. Further, the Mw 150 K glycoprotein has been used to trace the developmental origin of the AF cell type. AF cells, which generally form the majority of amniotic fluid cells found in culture, appear to arise in the extra-embryonic membranes, specifically the amnion.

Affinity Labels↗
PubMed1981

Stereoselective and non-stereoselective effects of D 600 (methoxyverapamil) in smooth muscle preparations.

Mechanical responses in guinea-pig ileal longitudinal, rat vasa deferentia and rat portal vein smooth muscle strips elicited by receptor activation (muscarinic or alpha-adrenergic) or by K+ depolarization were blocked by D 600 (methoxyverapamil). Stereoselectivity was observed with the (-)-enantiomer being more potent than the (+)-enantiomer (the ratio varying from 6 to 180). The tonic (slow) component of response was more sensitive than the phasic (fast) component. D 600 competitively blocked binding of (-)-[3H]QNB and [3H]WB 4101 to muscarinic and alpha-adrenergic receptors respectively, but in marked contrast to the effects on mechanical responses antagonism of ligand binding was non-stereoselective. It is suggested that stereoselectivity of action of D 600 may be a useful criterion to distinguish between its several sites of action.

Animals↗