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L McCoy

Publications and source records attributed to L McCoy.

33 records · Page 2Linked to original sources
PubMed1980

Value of serial CEA determinations in a surgical adjuvant trial of colorectal and gastric carcinoma.

At the Cross Cancer Institute in Edmonton, a concurrently controlled, randomized, prospective surgical adjuvant trial involving Dukes' B2 and C colorectal carcinoma and gastric carcinoma (T1-4, No-2, Mo) has been activated for the last two years. To date, a total of 150 patients have been entered into the three arms of the trial (namely control, immunotherapy, and chemoimmunotherapy). Of these, 127 cases are colorectal carcinoma and 28 are gastric cancer. As part of the protocol, serial CEA determinations are obtained in all patients on a regular three-monthly basis. So far, 28 patients have confirmed recurrence (colorectal 20, gastric 8) demonstrated clinically or radiologically. Out of these 28 patients, 25 (89.2%) had CEA greater than 2.5 ng/ml months before actual demonstration of recurrence. However, if one uses a cutoff of 5.0 ng/ml as significant, that is, one standard deviation from the usual accepted value, then 21 out of 28 (75%) had persistent, elevated CEA's months before the recurrence manifested itself clinically or radiologically. The CEA profiles of three representative cases from each arm of the adjuvant trial are included. It is suggested that serial CEA determinations will be an invaluable adjunctive test in following patients in an adjuvant trial setting.

Carcinoembryonic Antigen↗
PubMedDate not supplied

Induction of globin synthesis in K562 cells is associated with differential expression of transcription factor genes.

Globin gene switching may be mediated by proteins expressed during different stages of development. Their identification may clarify the mechanisms of the conversion from fetal to adult globin production and lead to new approaches to reversing or retarding the gamma- to beta-globin gene switch. To explore this hypothesis, K562 erythroleukemia cells were induced to differentiate with 1.25, 2.5, and 5 mM sodium butyrate and gene expression was studied after 24, 48, and 72 h. Erythroid differentiation was verified by benzidine staining and by measuring the activity of a transduced A gamma-globin gene promoter linked to a luciferase reporter gene. Using differential display polymerase chain reaction (PCR), total mRNA extracted from induced cells at each time point of induction was reverse transcribed in the presence of A, G, and C anchored primers and 16 arbitrary primers, calculated to amplify approximately 50% of expressed genes. Amplified mRNAs from induced and uninduced cells were separated in polyacrylamide gels and compared. More than 110 cDNA fragments which appeared to represent either up- or downregulated mRNA species in induced K562 cells were identified. Sixty-four of these fragments had more than 95% homology to known GenBank sequences. Seventeen fragments with characteristics of transcription factors were cloned. These include differentiation-related gene-1 (drg-1), PAX 3/forkhead transcription factor, HZF2 which is a Kruppel-related zinc finger protein, three helix-loop-helix proteins (heir-1, Id3, and GOS8), alpha-NAC transcriptional coactivator, LIM domain protein, and trophoblast hypoxia regulating factor. Differential expression of all 17 fragments over 72 h was confirmed by reverse Northern dot blot analysis, semiquantitative PCR using nested primers, and Northern analysis. Erythroid maturation in induced K562 cells is associated with differential expression of numerous genes. Some encode transcription factors that could effect the initiation of HbF synthesis. Almost half of the differentially expressed clones contained cDNAs of unidentified open reading frames and these are the object of continued study.

Blotting, Northern↗
PubMedDate not supplied

Alternate antimicrobial therapy for vancomycin-resistant enterococci burn wound infections.

Survival after a major thermal burn is precarious and fraught with difficult complications associated with hypermetabolism, gut or respiratory dysfunction, and infection. Clinicians must be cognizant of a new threat to the patient with burn injuries--the emergence of vancomycin-resistant enterococci (VRE). In an analysis of 31 clinical isolates obtained during acute burn hospitalization, an optimal antimicrobial therapy for VRE has been identified. All VRE cultures were inoculated to the MicroScan Gram-Positive Breakpoint Combo Panel #8 (Dade Microscan, Inc, Sacramento, Calif), which speciates the enterococci, provides antimicrobial susceptibility patterns (including vancomycin) and a biotype, and examines streptomycin and gentamicin synergy. Eleven (35.5%) of the 31 isolates were identified as E faecium and 20 (64.5%) as E faecalis. All isolates were susceptible to chloramphenicol and tetracycline, whereas only half were sensitive to gentamicin synergy screen. All other antimicrobials screened against VRE were either ineffective or of limited effect. Our preliminary data supports the initiation of chloramphenicol therapy when a VRE burn wound infection is encountered or suspected.

Anti-Bacterial Agents↗
PubMedDate not supplied

Is the limulus amebocyte lysate the sole predictor of septic episodes in major thermal injuries?

Septic episodes in thermal injuries are usually hallmarked by a series of physiologic parameters that include tachypnea, prolonged paralytic ileus, hyperthermia or hypothermia, altered mental status, thrombocytopenia, leukocytosis or unexplained leukopenia, acidosis, and hyperglycemia. Recent studies with polycystic kidney disease have clearly indicated that the limulus amebocyte lysate (LAL) assays were predictive of fungal infections in this patient population. Because both bacteria and fungi produce lipopolysaccharide that can be identified with the LAL assay, we randomly assayed sequential sera of 45 patients with major thermal injuries for positivity in the LAL assay, with use of the QCL-1000 kit (BioWhittaker, Walkersville, Md). The average burn size of this patient population was 63.43% total body surface area. The average age of the patient was 6.2 years. The sex distribution included 30 males and 15 females. The infectious agents included gram-positive cocci and gram-negative rods, and 14 patients had concomitant fungal infections. Eighty-five percent of the patients tested were positive for endotoxin, with levels ranging from < 0.1 EU/mL to > 1.0 EU/mL. The predominant organism isolated before or on the date the serum was drawn was Pseudomonas aeruginosa (51%), followed by Klebsiella pneumoniae (15%). The remaining 34% were a variety of Enterobacteriaceae. Of the 14 patients who yielded a fungus, 3 had negative LAL assays. Two patients with an elevated LAL grew only Staphylococcus epidermidis in the bloodstream and the wounds. These data clearly indicate that the LAL assay cannot be relied on as the sole predictor of septic episodes; however, it can be an adjunctive test to confirm sepsis when the other parameters have been considered.

Adolescent↗