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T D Coates

Publications and source records attributed to T D Coates.

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

An inherited defect of neutrophil motility and microfilamentous cytoskeleton associated with abnormalities in 47-Kd and 89-Kd proteins.

A 2-month-old male Tongan infant presented with fever, severe skin and mucosal infections, hepatosplenomegaly, thrombocytopenia, and normal neutrophil counts. While polymorphonuclear neutrophil (PMN) morphology was normal, several neutrophil motile functions were found to be altered in the patient. Furthermore, two siblings had died in infancy with a similar clinical picture, raising the possibility of an inherited neutrophil defect. Random migration and chemotaxis, assessed by the under agarose method, were profoundly impaired. Actin polymerization, as measured by flow cytometry of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)phallacidin (NBD-phallacidin)-stained PMNs, showed lower basal F-actin and a 1.75-fold increase in response to 10(-7) mol/L formyl-methionyl-leucyl-phenylalanine (FMLP) compared with a 4.51-fold increase in control. Microscopic examination of NBD-phallacidin-stained PMN spread on glass showed decreased area of spreading and F-actin-rich filamentous projections distinct from control. The early phase of FMLP-induced right angle light scattering was absent, similar to the effect caused by cytochalasin-B (CB), an inhibitor of actin polymerization. Accordingly, FMLP induced secretion of elastase without the addition of CB. Staphylococcus aureus killing was 50% of control whereas superoxide production response to FMLP and surface expression of CD11b were greater than twice normal. Partial defects in actin polymerization and scatter were seen in the parents and release of elastase, in the absence of CB, was also increased in both parents. Sodium dodecyl sulfate-polyacrylamide electrophoresis of whole cell proteins from the patient showed a marked decrease in an 89-Kd protein (8% of control) and a marked increase in a 47-Kd protein (4.2-fold). Both mother and father had decreased 89-Kd (77% and 42% of control) and increased 47-Kd proteins (2- and 3.4-fold), although neither had recurrent infections or chemotactic defects. These studies describe a new inherited actin dysfunction syndrome associated with severe propensity to fungal infection and draw attention to the proteins of apparent molecular weights of 89 Kd and 47 Kd, which may be of great importance in the regulation of actin polymerization in human PMNs.

Actin Cytoskeleton↗
PubMed1991

Treatment of experimental Pseudomonas keratitis with cyclo-oxygenase and lipoxygenase inhibitors.

The role of metabolites of arachidonic acid in experimental Pseudomonas keratitis was studied using inhibitors of arachidonic acid metabolism. Nordihydroguaiaretic acid 1%, which inhibits predominantly the lipoxygenase pathway, and flurbiprofen 0.03%, which inhibits predominantly the cyclo-oxygenase pathway were administered topically to rabbit eyes after intrastromal injection of Pseudomonas aeruginosa. Levels of the cyclo-oxygenase product prostaglandin E2 (PGE2) and the lipoxygenase product leukotriene B4 (LTB4) were measured, and the number of ulcers that had progressed to descemetocele formation by 24 hours was determined. Corneal ulceration was accelerated by flurbiprofen, but nordihydroguaiaretic acid limited the flurbiprofen-induced worsening. The use of flurbiprofen was associated with decreased levels of PGE2 and a relative increase in LTB4, a potent chemoattractant and activator of polymorphonuclear leukocytes. These results suggest that inhibition of the cyclo-oxygenase pathway may be contraindicated in Pseudomonas keratitis; inhibition of lipoxygenase can prevent this worsening of the keratitis.

Administration, Topical↗
PubMed1991

Qualitative functional deficiency of affinity-purified lactoferrin from neutrophils of patients with chronic myelogenous leukemia, and lactoferrin/H-ferritin-cell interactions in a patient with lactoferrin-deficiency with normal numbers of circulating leukocytes.

The iron-binding proteins lactoferrin (LF) and H-ferritin have been implicated in the negative regulation of myelopoiesis in vitro and in vivo. The present studies evaluated the functional activity of affinity-purified LF from polymorphonuclear neutrophils (PMN) of patients with chronic myelogenous leukemia (CML) and LF/H-ferritin-cell interactions in a nonleukemic patient with LF deficiency with normal levels of circulating blood leukocytes. Affinity-purified CML-PMN-LF was found to be qualitatively deficient as a suppressor of the release of colony-stimulating factors from mononuclear blood cells, adding to previous information from our group documenting defective LF-cell interactions in CML. LF was detected by immunoradiometric assay in PMN of the patient with LF deficiency, but at a much lower level than normal. This LF was found, however, to be active as a suppressor molecular against the patient's cells and normal donor cells. Patient cells were as responsive as normal cells to effects of purified milk LF. Decreased LF levels in this patient were associated with increased levels of monocyte H-ferritin inhibitory activity, consistent with the known suppressive effects in vitro of LF on H-ferritin release from monocytes. Patient marrow hematopoietic progenitor cells were as responsive as progenitors from normal donors to suppression by purified H-ferritin and prostaglandin E1. These results are consistent with a role of LF and H-ferritin in the control of myelopoiesis in this patient.

Alprostadil↗
PubMed1990

Inhibition of production of LTB4 and chemotactic agent from rat alveolar macrophages treated with t-butyl hydroperoxide is independent of ATP depletion.

In rat alveolar macrophages treated with 100 microM t-butyl hydroperoxide (tBOOH), leukotriene B4 (LTB4) synthesis was significantly lower than the basal level while levels of cyclooxygenase pathway products were increased. LTB4, 5,6-dihydroxyeicosatetraenoic acid (5,6-DiHETEs), and 5-hydroxyeicosatetraenoic acid (5-HETE) production in macrophages was significantly stimulated by 2 microM A23187, but this was suppressed 40% by simultaneous addition of 10 microM tBOOH and completely abolished by 100 microM tBOOH. Basal and A23187-stimulated macrophage production of chemotactic agents were similarly suppressed by addition of tBOOH; this effect paralleled depression of cellular LTB4 synthesis. In contrast to the significant depression of A23187-stimulated formation of 5-lipoxygenase products by 10 microM tBOOH, cellular adenosine triphosphate (ATP) was unchanged. Macrophages pretreated with KCN led to a 42% decline in ATP levels; however, LTB4, 5,6-DiHETEs, and 5-HETE production in response to A23187 was not suppressed. The results indicate that inhibition of 5-lipoxygenase pathway products in macrophages treated with tBOOH did not occur by depletion of cellular ATP levels.

Adenosine Triphosphate↗
PubMed1990

Neutrophil chemotactic heterogeneity to N-formyl-methionyl-leucyl-phenylalanine detected by the under-agarose assay.

Human polymorphonuclear neutrophils (PMNs) are heterogeneous in their response to the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP). By using a computerized imaging method for analysis of agarose chemotaxis plates, the chemotactic sensitivity of the population of PMNs at the leading front to FMLP was greater than the mean sensitivity of all migrating PMNs. When PMNs were treated with the membrane-perturbing agent butanol at concentrations up to 0.25%, chemotaxis of the fastest PMN population in response to 10(-7) mmol/L FMLP was increased to 140% of control, whereas the mean of all populations was increased to only 110% of control. These data show that the PMN population at the leading front has a different chemotactic sensitivity to FMLP. Furthermore, the susceptibility to butanol treatment of the PMN population suggests that an alteration in membrane properties may partly account for this difference.

Butanols↗
PubMed1989

Integration of nutrition support into oncologic treatment protocols for high and low nutritional risk children with Wilms' tumor. A prospective randomized study.

Benefits and risks of nutrition support were evaluated in 31 malnourished children with newly diagnosed Wilms' tumor managed according to the third National Wilms' Tumor Study protocol. Patients were classified at diagnosis as being at high nutritional risk (HNR, n = 19) or low nutritional risk (LNR, n = 12). Ten HNR patients were randomized to central parenteral nutrition (CPN) and nine HNR patients were randomized to peripheral parenteral nutrition (PPN) plus enteral nutrition (EN) for 4 weeks of initial intense treatment and EN (nutritional counseling, oral foods and supplements) thereafter. Thirteen HNR patients (seven CPN, six PPN) completed the protocol. Twelve LNR patients received EN; 11 Stage I malnourished patients were randomized to 10 or 26 weeks of chemotherapy. Dietary, anthropometric, and biochemical data were determined for HNR patients at weeks 0-4, 6, 13, 19, and 26 and for LNR patients at weeks 1, 2, 5, and 26. In HNR patients, adequate parenteral nutrition support reversed protein energy malnutrition (PEM), and prevented chemotherapy and radiotherapy delays due to granulocytopenia. CPN was superior to PPN in reversing PEM: energy intake, weight gain, and retinol binding protein were higher (P less than 0.05). LNR patients lost weight and fat reserves in the first 2 weeks of treatment; depletion persisted at week 5, and 25% had chemotherapy delays. Thereafter, EN reversed PEM in patients with both chemotherapy regimens. These data suggest that CPN is preferable during initial intense treatment for HNR patients, and that, although EN is ineffective in preventing depletion and treatment delays in the first 5 weeks of treatment for LNR patients, it is effective thereafter.

Abdomen↗
PubMed1989

Effectiveness of two methods of parenteral nutrition support in improving muscle mass of children with neuroblastoma or Wilms' tumor. A randomized study.

The short-term and long-term effectiveness of central parenteral nutrition (CPN) versus peripheral parenteral nutrition (PPN) in improving muscle mass (arm muscle area [AMA]) was evaluated for 24 malnourished children with newly diagnosed Stage IV neuroblastoma (n = 14) or Stages II-V Wilms' tumor (n = 10). Patients were randomized to either CPN or PPN plus enteral nutrition (EN: intense nutrition counseling, oral foods, and supplements) for 4 weeks followed by EN until week 10. Oncologic treatment was similar for each tumor type. Dietary, anthropometric, and biochemical measurements were obtained at weeks 0, 4, and 10. During weeks 1 through 4, energy (CPN: means 100 +/- 4; PPN: means 96 +/- 4% of healthy children) and protein (CPN: means 2.5 +/- 0.1; PPN means 2.7 +/- 0.2 g/kg) intakes of the two groups did not differ. The AMA increased (P less than 0.05) with 4 weeks of CPN but not with PPN; changes thereafter with EN were not significant. Weight (P less than 0.05) and triceps skinfolds (P less than 0.01) increased with 4 weeks of PN in both groups and decreased with EN thereafter (P less than 0.01) but were higher at week 10 than diagnosis. Increases in albumin in both groups reached significance at week 10 (P less than 0.05). These data show that CPN improves AMA in malnourished children with neuroblastoma or Wilms' tumor when energy and protein intakes are adequate. The AMA gains can be maintained thereafter with EN.

Anthropometry↗
PubMed1989

Pharmacology studies of 1-beta-D-arabinofuranosylcytosine in pediatric patients with leukemia and lymphoma after a biochemically optimal regimen of loading bolus plus continuous infusion of the drug.

In an attempt to maximize the therapeutic index and to overcome the large variations in 1-beta-D-arabinofuranosylcytosine (ara-C) plasma levels and host toxicities that have been documented with standard HDara-C regimens (3 g/m2 over 3 h every 12 h x 8 or x12 doses), pediatric patients with acute lymphocytic leukemia or lymphoma in relapse were treated with a regimen of loading bolus followed immediately by continuous infusion of ara-C. In addition, patients received a single dose of etoposide (VP-16, 1 g/m2) prior to the ara-C administration. In four patients, total body irradiation was administered as part of a bone marrow transplantation preparative regimen after the ara-C administration. The regimen was designed to attain and maintain plasma steady-state concentrations (Css) of ara-C three to four times the Km2 value of ara-C, which was determined with purified deoxycytidine kinase from the patients' tumor cells prior to treatment. Eight patients age 0.75 to 16 years with relapsed acute lymphocytic leukemia (three patients) or lymphoma (five patients, one with bone marrow involvement), received a test dose of 3 g/m2 ara-C injected over 1 h, and the plasma kinetics were determined. The peak plasma ara-C concentration of ara-C ranged from 57 to 199 microM with an average concentration of 103 +/- 49 microM; the half-lives of distribution (t1/2, alpha) and elimination (t1/2, beta) averaged 17 +/- 7 min and 4.04 +/- 3.1 h, respectively. The mean area under the plasma concentration time curve from 0 to 12 h (AUC0----12 h) of ara-C averaged 386.8 +/- 328.0 microMh (mean, +/- SD, n = 8). The peak concentration of uracil arabinoside averaged 501 +/- 123 microM, and it was eliminated with a t1/2, el of 2.3 +/- 0.6 h. The patients then received an individualized loading bolus (mean = 0.5 g/m2) followed by a continuous infusion regimen of ara-C (mean = 130 mg/m2/h), to achieve a Css in the range of 20 to 35 microM. The obtained plasma Css were similar to the desired ones, averaging in variation 10.7% +/- 8.2%. The percentage of variation of correlation of the AUC following the loading bolus plus the continuous infusion from 12 to 72 h was only 12.4% (mean = 2158 microMh, n = 8), whereas the percentage of variation of correlation of the AUC after the test dose of ara-C in the same patients was 84.8%.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1988

Role of selenium-dependent glutathione peroxidase in antioxidant defenses in rat alveolar macrophages.

Glutathione peroxidase is a crucial component of cellular antioxidant defenses. Using tertiary butyl hydroperoxide (tBOOH) as a model for oxidant stress in alveolar macrophages, we determined the effectiveness of glutathione peroxidase in preventing both cell "death" (lactate dehydrogenase release) and more subtle alterations in cell function. The KM of glutathione peroxidase for tBOOH was 54 microM, and the Vmax was 26 nmol/min/10(6) cells in alveolar macrophages. Concentrations of tBOOH greater than 100 microM caused lactate dehydrogenase release; however, a lag greater than 30 min was observed when with 10 mM tBOOH. With 200 microM tBOOH, the rate of decrease in membrane potential, measured by 3,3'-dipentyloxacarbocyanine iodide fluorescence, inversely correlated with glutathione peroxidase. Computer-enhanced microscopy showed that this fluorescence predominately was in mitochondria. NADPH fluorescence was altered in selenium-deficient alveolar macrophages; the tBOOH-dependent rate of NADPH oxidation was slowed, and higher concentrations of tBOOH were required to disturb the steady state NADPH/NADP+ ratio. Although alteration in NADPH or glutathione oxidation can reflect oxidant stress and can adversely affect cell function, such a change does not dictate irreversible injury. Nevertheless, irreversible injury by oxidants appears to involve an overwhelming of the glutathione-NADPH antioxidant system.

Animals↗
PubMed1987

Localization of chlorotetracycline fluorescence in human polymorphonuclear neutrophils.

Chlorotetracycline (CTC) has been used in many cells as a probe for membranous calcium. In polymorphonuclear neutrophils (PMN), the changes in CTC fluorescence upon stimulation are considered to monitor an early event in the activation process. Using quantitative video-enhanced microscopy, we report that in resting cells about 80% of the CTC signal emanates from the perinuclear region of the cell, indicating that internal structures are labeled with CTC. Approximately 20% of the total CTC fluorescence is taken up in a compartment sensitive to mitochondrial inhibitors, which is not present in neutrophils depleted of nucleus and granules or cytoplasts. Upon stimulation PMN loaded with CTC exhibit a rapid, biphasic decrease in fluorescence that is dose dependent. The second phase of the response is not seen in neutrophil cytoplasts. These results suggest that internal stores of CTC are responsive upon stimulation and could account for the later decrease in CTC fluorescence, whereas the early phase of CTC changes represents the plasma membrane response.

Calcium↗
PubMed1986

The value of nutrition support in children with cancer.

A positive stance towards nutrition support of the child with cancer assures potential for normal growth, development, and quality of life during extended oncologic treatment. Data from recent studies of children with cancer (advanced neuroblastoma, Wilms' tumor) demonstrate the importance of integrating nutrition staging, assessment, and support into treatment protocols. Patients with solid tumors and lymphomas who are malnourished at diagnosis have a poor outcome when compared to nourished counterparts. Enteral nutrition (intensive nutrition counseling and favorite, nutritious foods) is effective in low nutritional risk groups but ineffective in preventing or reversing protein-energy malnutrition in high nutritional risk groups. For high-risk groups, central parenteral nutrition is a relatively short-term, but important, support measure which allows children to grow despite extended periods of intense oncologic treatment. The patient's nutritional course may affect bone marrow suppression and the ability to tolerate aggressive chemotherapeutic treatment. Although treatment tolerance may be improved with nutrition support, adequacy of primary oncologic treatment outweighs other supportive factors as a determinant of ultimate survival.

Anthropometry↗
PubMed1986

Nutritional support of children with neoplastic diseases.

There are numerous factors promoting the development of PEM in the child with cancer. Some of these factors are related to the tumor, many to the treatment itself, and some to failure of recognition of PEM. Not all children with cancer are at great risk for the development of PEM. These patients must be monitored and supported with comprehensive enteral programs. Children who have developed or are at risk for PEM must be identified and supported with CPN or PPN plus CEN during early intensive periods of treatment and during the later phases of abdominal radiotherapy, operative resection of tumor, or relapse. The decision to institute CPN must be based not only on the child's current nutritional status but also on the nature of the therapy he or she is soon to receive and the likelihood that he or she will be able to maintain an adequate intake during that therapy. Realistic goals must be set for nutritional support. The value of nutritional intervention lies in its ability to correct or prevent the development of adverse effects related to PEM. This support is hoped to contribute to improved tolerance of therapy, increased energy to complete normal day-to-day activities, and an improved sense of well-being for the child. If these goals have been accomplished, then the nutritional therapy has been successful.

Anthropometry↗
PubMed1986

Angiomatoid malignant fibrous histiocytoma with extensive lymphadenopathy simulating Castleman's disease.

We report the association in a 10-year-old boy of an angiomatoid malignant fibrous histiocytoma (AMFH) of the left thigh with ipsilateral inguinal, pelvic and extensive retroperitoneal lymphadenopathy, and severe systemic manifestations. These include growth retardation, fever, severe anemia, hypergammaglobinemia, and hypoalbuminemia. At ultrastructural level the tumor was characterized by an abundance of myofibroblasts, occasional histiocytes, and small vessels with marked reduplication of the basal lamina. Biopsies of the inguinal and abdominal lymph nodes showed follicular hyperplasia and massive plasmacytosis indistinguishable from Castleman's disease (giant lymph node hyperplasia) of plasma cell type. The radical surgical excision of the primary tumor in the thigh resulted in the disappearance of the abdominal lymphadenopathy and a marked reduction in size of the pelvic lymph nodes with marked decrease of the gammaglobulins, thus proving that the nodal lesions were the expression of a reactive process to the tumor rather than a coincidental independent lymphoproliferative disorder. Retroperitoneal and pelvic node dissection was performed 1 year after the radical excision of the thigh tumor because of persistent pelvic lymphadenopathy and failure of serum immunoglobulins M and A to return to normal level, with a recent peak of IgA to twofolds that of normal value. Metastatic AMFH was found in the three pelvic nodes. One month postoperatively IgA returned to near normal level whereas IgM remained slightly elevated.

Castleman Disease↗
PubMed1986

Advances in nutrition care of children with neoplastic diseases: a review of treatment, research, and application.

Within the last decade, significant advances have been made both in treating children with cancer and in providing proper nutrition support. Oncologic treatment and nutrition research and their application to the nutrition care of children with cancer are reviewed. Quality nutrition care is now possible because of an improved understanding of (a) the prevalence and significance of protein-energy malnutrition (PEM) in high-risk groups, (b) the staging and assessment of nutritional status, and (c) the efficacy and limitations of nutrition support options. Nutrition staging, assessment, and support should be integrated into treatment protocols for children with neoplastic diseases. Common risk factors for the development of PEM have been identified from serial monitoring of newly diagnosed children with a variety of tumors. Certain tumor types and their treatment can be classified within either low or high nutritional risk groups. A comprehensive nutrition program (intense nutrition counseling, favorite nutritious foods) is preferred for low nutritional risk groups but is ineffective in preventing or reversing PEM in high-risk groups. For high-risk patients, central parenteral nutrition (CPN) is the method of choice as a relatively short-term but important support measure that allows children to withstand long intervals of intense treatment during periods of growth and development. Current data suggest that bone marrow suppression may be attenuated and treatment tolerance improved with the use of CPN in selected children with advanced cancer (e.g., acute nonlymphocytic leukemia or advanced neuroblastoma).

Child↗
PubMed1985

Short- and long-term effectiveness of enteral and parenteral nutrition in reversing or preventing protein-energy malnutrition in advanced neuroblastoma. A prospective randomized study.

The effectiveness of enteral and parenteral nutrition regimens in preventing or reversing protein-energy malnutrition (PEM) and in preventing treatment delays was evaluated in 32 children receiving treatment for newly diagnosed Stage III (3 patients) and IV (29 patients) neuroblastoma. Ten of 18 malnourished patients were randomized to central parenteral nutrition (CPN) and 8 to peripheral parenteral nutrition (PPN) plus enteral nutrition for 4 weeks and then received enteral nutrition (EN: intense nutrition counselling, oral foods and supplements) for weeks 5 through 10. Ten of 14 nourished patients received EN and 4 CPN for 4 weeks and EN thereafter. Dietary, anthropometric and biochemical measurements were determined for weeks 0, 1, 2, 3, 4, 7, and 10 for 24 patients who completed the protocols. In malnourished patients, both CPN (seven patients) and PPN (seven patients) were effective in reversing PEM in the first 4 weeks; thereafter, EN effectively maintained nutritional gains in both groups. In nourished patients, EN (seven patients) was not as effective as CPN (three patients) in preventing PEM during the first 4 weeks; afterwards, EN maintained gains in the CPN group but did not promote needed increases in weight nor fat reserves in the EN group. Patients supported by parenteral nutrition (PN, weeks 1-4) had fewer treatment delays (2/17, 12%) than EN patients (4/7, 57%, P less than 0.05). These data indicate that PN reverses or prevents PEM and prevents treatment delays during the first 4 weeks of intense oncologic treatment and provides nutritional benefits which can be maintained with EN thereafter.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

A microcomputer-based program for video analysis of chemotaxis under agarose.

We have developed a computerized system for the quantification of video images of cell migration patterns obtained in the chemotaxis under agarose assay. This system allows either manual or automatic measurement of standard parameters of chemotaxis, as well as quantification of three new parameters which reflect mean cell movement and chemokinesis. The parameters of mean cell population movement are not obtainable by the traditional analysis of the chemotaxis under agarose assay. Our system operates on an inexpensive microcomputer, is easy to use and provides data output in a format that is directly transferable to standard statistical packages.

Chemotaxis, Leukocyte↗