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D W Ross

Publications and source records attributed to D W Ross.

At least 37 records · Page 2Linked to original sources
PubMed1991

Mitochondrial Eve.

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DNA, Mitochondrial↗
PubMed1990

Neutrophil myeloperoxidase measurement uncovers masked megaloblastic anemia.

We report the observation of a high neutrophil myeloperoxidase activity (MPXI) in patients with megaloblastic anemia. MPXI is rapidly measured as part of an automated complete blood count (Technicon H*1, Technicon Instruments Corp, Tarrytown NY). We describe the range of MPXI levels in healthy and patient populations and in 10 cases of megaloblastic anemia, including five having elevated mean cell volume (MCV) and five without macrocytosis. Regardless of the MCV, our megaloblastic patients had hypersegmented neutrophils and elevated MPXI levels without visible alteration of granule content. MPXI measurement may be particularly useful in identifying cases of "masked megaloblastic anemia" where the MCV is below 100 fL. The advantage of the MPXI over other methods of uncovering masked megaloblastic anemia is its simplicity when performed as part of a routine complete blood count on an automated hematology instrument.

Adolescent↗
PubMed1990

Pathology.

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Pathology↗
PubMed1990

Whole blood staining in suspension for nonspecific esterase and alkaline phosphatase analyzed with a Technicon H-1.

We adapted previously published methods for nonspecific esterase and alkaline phosphatase staining of white blood cells in suspension for use on a Technicon H-1 hematology analyzer. The objective was to develop a semiautomated method using whole blood that could be employed on a large scale for hematology laboratory applications, including toxicology studies, measurement of neutrophil left shift, and cytochemical classification of myeloid leukemias. The nonspecific esterase method uses the pararosaniline stain, generating the unstable substrate from two stable precursors. Whole blood is added to the substrate plus dye mix. Next, acid lysis and fixation steps destroy red cells and stabilize the monocyte staining. The alkaline phosphatase stain employs a stable naphthyl phosphate substrate and fast blue B coupling dye. The red cells are lysed with a pH 10.3 propanediol buffer, and the white blood cells are then stabilized with formalin fixation. For both methods the staining is performed off-line, and the sample is then diluted with propanediol to match the refractive index of the sheath on the H-1 analyzer, before aspiration into the direct cytometry port. A cytogram of scattered versus absorbed light is obtained. The number of cells staining and the intensity of the stain can be quantified from the cytogram.

Alkaline Phosphatase↗
PubMed1990

Bcr/abl recombinant DNA analysis versus karyotype in the diagnosis and therapeutic monitoring of chronic myeloid leukemia.

Karyotype and bcr/abl recombinant DNA analyses are two means of detecting the chromosomal aberration in chronic myeloid leukemia. The authors compared these two methods in a retrospective study of 36 patients with CML in which they found the bcr/abl DNA recombinant event in 100% (29 of 29) of those patients who had the Philadelphia chromosome. To achieve this sensitivity, a battery of two bcr probes and three restriction enzymes is necessary. The authors propose a sequential algorithm for efficient use of these probes and enzymes. In 76% of the patients, bcr/abl rearrangement can be detected with a Bgl II digest and a 3' commercial probe. An additional 21% of patients can be detected by a second assay in which the same membrane is rehybridized to a 3' and 5' combination bcr probe. One patient (3%) required an additional restriction enzyme digest with BamH I to detect the recombinant event by the same 3' probe. Karyotype analysis is used to determine cytogenetic remission in patients with CML under therapy. The authors studied the use of DNA analysis by the Southern blot technique to detect a decrease in the relative number of leukemic cells. By dilution studies and densitometric scanning of autoradiographs, the authors were able to detect a 15% decrease in the relative number of cells having the bcr/abl recombinant event. The authors report the preliminary results of three patients in whom they compared the karyotype and recombinant DNA analysis at multiple time points in their clinical course. In conclusion, the bcr/abl recombinant DNA analysis is superior to karyotype for the diagnosis of CML and can be used for monitoring treated patients.

Adolescent↗
PubMed1990

Restriction enzymes.

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DNA Restriction Enzymes↗
PubMed1990

Recombinant DNA laboratory data manager using DBASE III+.

The use of recombinant DNA technology in clinical and research laboratories involves diverse information management functions such as keeping track of patient samples, blot membranes, polymerase chain reaction products and test results. We report here the use of a PC-based database manager (DBASE III+, Ashton-Tate) for the coordinated maintenance of these functions. We have implemented a menu driven interface, developed using DBASE's programming language, which provides a data entry and maintenance system. The system is easily learned by technologists and saves time and reduces data handling errors compared to a manual method. The system can rapidly look up data and produce customized worksheets or reports correlating all available clinical and laboratory information. We will provide a copy of the program disc to interested parties.

DNA, Recombinant↗
PubMed1989

Simultaneous paired analysis by flow cytometry of surface markers, cytoplasmic antigens, or oncogene expression with DNA content.

Flow cytometry is a useful tool for measuring DNA content and differentiation as expressed by cell surface markers. We have extended this technology to measure simultaneously either surface, cytoplasmic, or nuclear antigens (particularly oncoproteins) with DNA content. Mononuclear blood cells isolated from normal subjects and HL60 leukemic cells were permeabilized and fixed in suspension utilizing 40 micrograms/ml lysolecithin and 1% paraformaldehyde. A range of lysolecithin concentrations in 1% paraformaldehyde was studied to optimize permeabilization of the antibodies to the cell interior without destroying cell integrity. The optimal concentration (40 micrograms lysolecithin/ml) resulted in good cell recovery with a high percentage of cells positive for surface and intracellular antigens. Cells are first stained with fluorescein isothiocyanate conjugated (FITC) antimyeloperoxidase (an azurophil granule enzyme), or with an anti-c-myc antibody and FITC goat anti-mouse IgG F(ab')2. Cells are then incubated with RNase and stained for DNA content with propidium iodide. Alternatively, cells were stained for the cell surface markers Leu M3, OKM1, or the transferrin receptor and were then fixed and permeabilized and stained with propidium iodide. Using this method, we correlated cytoplasmic, nuclear, or cell surface antigens with cell cycle kinetics. This technique should be useful for studies of cellular differentiation and proliferation.

Antigens, Surface↗