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T R Hamill

Publications and source records attributed to T R Hamill.

5 recordsLinked to original sources
PubMed1996

A case of composite Hodgkin's disease and chronic lymphocytic leukemia in bone marrow. Lack of Epstein-Barr virus.

We report Hodgkin's disease arising in a 68-year-old patient with a history of chronic lymphocytic leukemia for 8 years. The patient presented with a 4-month history of weakness, loss of appetite, and a 15-pound weight loss. A bone marrow biopsy showed two distinct histologic types of lymphoma: chronic lymphocytic leukemia and Hodgkin's disease. Immunohistochemical studies showed that chronic lymphocytic leukemia cells were composed of kappa-light chain-restricted monoclonal B cells. The Reed-Sternberg cells expressed CD15. Epstein-Barr virus RNA was not identified in either the Reed-Sternberg cells or cells of chronic lymphocytic leukemia by in situ hybridization. To our knowledge, this is the second reported case of composite Hodgkin's disease and chronic lymphocytic leukemia involving the bone marrow.

Aged↗
PubMed1990

The 30-minute rule for reissuing blood: are we needlessly discarding units?

The standards of the American Association of Blood Banks require that blood for reissue must be maintained continuously between 1 and 10 degrees C. To comply with this standard, most transfusion services have set a 30-minute limit on the time that a unit of blood can be out of a monitored refrigerator before it must be discarded. The primary reason for such a time limit is to reduce the risk that small numbers of contaminating bacteria could grow to lethal numbers before the blood is administered. An extensive review of the pertinent literature revealed that the organisms that may survive refrigeration (i.e., psychrophilic bacteria) are unable to begin logarithmic phase growth for several hours after returning to room temperature. This is due to alterations in bacterial enzyme systems and membrane lipids that occur during growth at refrigerator temperatures and that must be repaired before rapid growth may occur. On the basis of this information, it appears that the 30-minute limit could be extended to 2 hours without any increased risk to the recipient. Such a policy change could save 18,000 units of blood per year in the United States.

Bacteria↗
PubMed1990

Effects of room-temperature exposure on bacterial growth in stored red cells.

Experiments were performed to determine the effect of room-temperature (RT) exposure on the growth rates of selected bacteria by deliberate contamination of AS-1 packed red cell (RBC) units contained in PL146 plastic bags. Isolates of Staphylococcus aureus, S. epidermidis, Streptococcus faecalis, Pseudomonas aeruginosa, Citrobacter freundii, Enterobacter agglomerans, and Yersinia enterocolitica were inoculated into 3- to 5-day-old packed RBC units. The units were refrigerated at 4 to 6 degrees C for 14 days. On two occasions during this period, one-half of the units were removed from the refrigerator and held at 25 to 26 degrees C for 2 hours. Timed samples taken during the periods at RT revealed stable or decreasing bacterial counts in the majority of exposed units, and in no instance was a marked increase in bacterial growth observed. Samples taken after subsequent prolonged rerefrigeration showed no significant increase in bacterial counts as compared with those in control units that were refrigerated constantly. These results indicate that RT exposure of contaminated RBC units does not result in accelerated bacterial proliferation over a period of 2 hours and that it may, in fact, have a detrimental effect on bacterial growth.

Bacteria↗
PubMed1984

Correlation of color vision deficits and observable changes in the optic disc in a population of ocular hypertensives.

Both glaucomatous cupping and the presence of acquired color vision deficits have been reported to be precursors to the onset of visual field defects in patients with suspected glaucoma. To examine the relationship between early glaucomatous cupping and acquired color vision anomalies, we performed anomaloscope (Pickford-Nicholson) and Farnsworth-Munsell 100-Hue color vision tests in 48 ocular hypertensive eyes with either clinical evidence of early glaucomatous cupping (group 1) or no evidence of glaucomatous cupping (group 2). All patients had normal visual fields, as determined by extensive static perimetry of the central visual field and kinetic perimetry of the peripheral visual field. Although the overall incidence of blue and blue-green color vision anomalies in the ocular hypertensives was comparable with that reported in previous studies, we found no clear association between early glaucomatous cupping and color vision anomalies. The relationship between these two precursors to visual field loss remains unclear.

Adult↗