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T J Reid

Publications and source records attributed to T J Reid.

33 records · Page 2Linked to original sources

Constitutional heteromorphism of 9q13 --> q21 in a patient with chronic myelogenous leukemia.

Cytogenetic studies were carried out in a 44-year-old white male because of newly diagnosed chronic myelogenous leukemia. His initial bone marrow study revealed 46,XY, var(9)(q13 -->q21)/46,XY,var(9) (q13-->q21), t(9;22)(q34;q11) karyotypes and later he also acquired a 47,XY,+8,var(9)(q13-->q21), t(9;22)(q34;q11) clone. The var(9)(q13-->q21) heteromorphism was observed in the normal 9 homolog, in 200 GTG-banded bone marrow metaphases in seven cytogenetic studies (1988-90). This heteromorphism was observed in the normal cell line, in the two chronic myelogenous leukemia-related clones, as well as in 100 mitogen-induced peripheral blood lymphocytes, indicating its constitutional nature. This seems to be the first report of var(9)(q13 --> q21) heteromorphism, involving GTG-positive euchromatic band, in a chronic myelogenous leukemia proband.

Adult↗

Pure red cell aplasia after chemotherapy for Hodgkin's lymphoma: in vitro evidence for T cell mediated suppression of erythropoiesis and response to sequential cyclosporin and erythropoietin.

Acquired pure red cell aplasia (PRCA) has been associated with various lymphoproliferative conditions but its occurrence with Hodgkin's disease is rare. We report a case of PRCA occurring immediately following the completion of induction chemotherapy in a patient with Stage IIIB nodular sclerosing Hodgkin's disease. In vitro erythroid colony studies documented evidence for T cell mediated suppression of erythropoiesis and lack of a serum inhibitor. Addition of cyclosporin to the in vitro cultures stimulated erythroid colony growth. Following in vivo treatment with cyclosporin peripheral blood CD4/CD8 ratios returned to normal. However, serum erythropoietin levels were inappropriately low. Subsequent treatment with erythropoietin induced a reticulocytosis and transfusion independence. Since discontinuing the erythropoietin, the patient has been able to maintain a hemoglobin of 100 g/L. This case illustrates that red cell aplasia occurring in the setting of Hodgkin's disease may be due to T cell mediated suppression of erythropoiesis. A response to cyclosporin may be masked by inappropriately low erythropoietin levels.

Adult↗

Inhibitory effects of HIV-1-infected stromal cell layers on the production of myeloid progenitor cells in human long-term bone marrow cultures.

This report presents the results of studies using long-term bone marrow cultures (LTBMC) of human bone marrow cells to investigate the effect of HIV-1 on in vitro hematopoiesis. Confluent stromal cell layers established from human bone marrow cells were irradiated to eliminate residual hematopoietic progenitor cells and exposed to HIV-1ADA or to HIV-1IIIB, monocytotropic and lymphocytotropic strains of HIV-1, respectively. A productive infection did not develop in cultures exposed to HIV-1IIIB but did for cultures exposed to HIV-1ADA as there was a progressive increase in HIV-1 p24 antigen. Stromal cell layers infected with HIV-1ADA were also cocultured with autologous CD34+ bone marrow cells. Four days, 1, 2, and 3 weeks later, the number of colony-forming units granulocyte/macrophage (CFU-GM) in non- and HIV-infected LTBMC was determined. The number of CFU-GM increased during the first week in both non- and HIV-infected LTBMC. One week after the coculture of CD34+ cells with stromal cell layers infected with HIV-1ADA, the number of CFU-GM in six out of eight experiments was reduced compared to noninfected control LTBMC. In those six experiments, the number of CFU-GM was 53 +/- 6% standard error of the mean (SEM) of the number in noninfected LTBMC. A reduced number of CFU-GM was observed in the nonadherent fraction of HIV-infected LTBMC for at least 2 weeks. These results demonstrate that some cells in the stromal cell layers of LTBMC were targets for HIV-1 and that HIV-infected stromal cell layers suppressed or delayed the production of CFU-GM.

Antigens, CD↗

A quantitative thrombin time for determining levels of hirudin and Hirulog.

The anticoagulant effect of recombinant hirudin (rHir) and Hirulog has been monitored in patients with the activated partial thromboplastin time. Accurate monitoring with this test cannot be achieved if plasmas contain heparin, lupus anticoagulants, low concentrations of fibrinogen or other factors, or elevated fibrinogen-fibrin degradation products (FDP). We have therefore developed a simple, rapid, sensitive clot-based method, the quantitative thrombin time (QTT), to measure levels of rHir and Hirulog in patient plasma (or whole blood). The QTT is performed by mixing a 1:10 dilution of patient plasma (50 microliters) with human fibrinogen (50 microliters, 128 mg/dl) at 37 degrees C; the clotting time is initiated by adding human thrombin (50 microliters, 5-7.5 U/ml). The concentration of Hirulog or rHir in plasma can be determined by comparing the QTT in patient plasma with a standard curve that is generated by adding different concentrations of anticoagulant to pooled normal plasma. Studies with whole blood using the same procedure yield similar results. In the absence of Hirulog or rHir, the baseline QTT is the same in normal and abnormal plasmas (fibrinogen < 150 mg/dl and FDP as high as 1024 micrograms/ml, elevated FDP alone, lupus anticoagulant, or heparin < 0.9 U/ml). When known concentrations of either rHir or Hirulog are added to abnormal plasmas, the mean observed concentrations as determined by the QTT deviate from the expected values by less than 10% (range 0-19%). The data indicate that the QTT is a simple, rapid, and accurate test for the determination of levels of rHir and Hirulog in plasma or whole blood.

Heparin↗

Iron malabsorption in a patient with large cell lymphoma involving the duodenum.

Iron malabsorption compounded the anemia in a patient with diffuse large cell lymphoma involving the small intestine. Both upper gastrointestinal series with small bowel follow-through and computerized tomographic scan demonstrated lymphomatous involvement of the duodenum and proximal jejunum by a retroperitoneal mass. An oral iron-loading absorption test was consistent with malabsorption of iron. After two cycles of systemic chemotherapy, the retroperitoneal mass resolved and the iron loading test normalized.

Adult↗

Free protein S deficiency in a family with venous thrombosis.

Inherited deficiencies of protein S, an inhibitor of the coagulation system, are now recognized as occurring at least twice as frequently as antithrombin III deficiency in patients with venous thrombosis. Protein S is present in plasma in a complexed form, which is inactive, and in a free or functional form. Free protein S combines with activated protein C to inhibit factors V and VIII. This report describes the evaluation of a family with recurrent deep venous thrombosis and superficial thrombophlebitis. Levels of antithrombin III and protein C as well as plasminogen were normal. The levels of total protein S, which includes the value for the free and complexed forms of protein S, were also normal. However, the free protein S levels were greatly reduced in all symptomatic members who were studied. This report illustrates the importance of obtaining measurement of free protein S levels in patients who are suspected of having inherited venous thrombotic disorders.

Adult↗

Chemical derivatization as a strategy to enhance detectability of agents used in cancer management.

The bioanalysis of drugs used in the management of cancer is often complicated by the lack of selectivity and sensitivity. Chemical derivatization of these drugs prior to their chromatographic analysis represents a viable strategy to improve chromatographic resolution and to enhance detectability. This review provides examples of how this approach can meet these objectives. Derivatization of racemic cyclophosphamide with a chiral acylating agent, following hydroxyalkylation to introduce a reactive centre into the molecule, provides the basis for its stereospecific analysis. The analysis of dianhydrogalactitol is described, in which diethyldithiocarbamate is used as a nucleophilic derivatizing agent that improves chromatographic behaviour and analytical sensitivity. The final example that is described is the design and preparation of improved fluorogenic reagents (o-phthalaldehyde analogues) for the derivatization of peptides and application of these reagents to the trace analysis of leu-enkephalin in plasma.

Journal Article↗

Consistency of care in an intensive care nursery staffed by nurse clinicians.

Variables related to both the process and outcome of newborn intensive care were studied to evaluate care consistency in a level 3 Newborn Intensive Care Unit (NICU) where neonatal nurse clinicians function in a role usually held by pediatric house officers. In routine delivery of intensive care, there were no statistically significant diurnal variations in the overall mortality, maintenance of intravenous infusions, tolerance of oral feedings, or respiratory care except a decrease in frequency of blood gas sampling during the weekday days as compared with nights. Our data suggest that a tertiary NICU in which medical coverage by neonatologists is supplemented by carefully trained and supervised neonatal nurse clinicians provides a consistent level of care that does not vary between night and day or day of the week.

Blood Gas Analysis↗

Changes in cattle tick control practices in south eastern Queensland from 1977 to 1982.

Results of a survey of cattle producers in south eastern Queensland in 1982 concerning cattle tick control have been compared with those of a similar survey carried out in 1977-78. During the interval between these surveys the proportion of beef farms with tick resistant (Bos indicus infusion) cattle as the main breed had increased from 47.8% to 60.0%. Chemical control methods had improved but many producers were continuing to treat their cattle more often than necessary. Over the period there was an increase in the proportion of farms with small numbers of animals, and 30% of the farms had less than 50 cattle.

Animals↗

Newborn cyanosis.

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Cyanosis↗

Structure and heme environment of beef liver catalase at 2.5 A resolution.

Most of the amino acid side chains of beef liver catalase were clearly identifiable in the 2.5 A resolution electron-density map, and the results are in good agreement with the sequence [Schroeder, W. A., Shelton, J. R., Shelton, J. B., Roberson, B. & Apell, G. (1969) Arch. Biochem. Biophys. 131, 653-655]. The tertiary structure of one subunit consists of a large antiparallel beta-pleated sheet domain with helical insertions, followed by a smaller domain containing four alpha-helices. The heme group is buried at least 20 A below the molecular surface and is accessible by a channel lined with hydrophobic residues. The proximal ligand is tyrosine-357, while histidine-74 and asparagine-147 re the important residues on the distal side of the heme. The inhibitor 3-amino-1,2,4-triazole, which has been shown to covalently bond to histidine-74, can be built into the heme cavity with its N(2) atom coordinated to the heme iron.

Animals↗