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Biomedical subjects

J C McCann

Publications and source records attributed to J C McCann.

9 recordsLinked to original sources
PubMed1996

High degree of occult tumor contamination in bone marrow and peripheral blood stem cells of patients undergoing autologous transplantation for non-Hodgkin's lymphoma.

Twenty patients with non-Hodgkin's lymphoma (NHL), primarily intermediate-and high-grade, were evaluated for evidence of bone marrow (BM) or peripheral blood stem cell (PBSC) lymphoma contamination using tumor-specific oligonucleotide-polymerase chain reaction (TSO-PCR). Patients were enrolled in a single-institution study comparing PBSC and bone marrow transplantation (BMT) for relapsed NHL. A molecular marker (CDR3 rearrangement, T cell beta receptor [TC beta R] rearrangement, or BCL-2/IgH rearrangement) was identified from analysis of the diagnostic tissue in 17 of 20 patients. Prior to undergoing BMT, 14 of 17 patients had PCR evidence of lymphoma involvement of either BM (11/17) or PBSCs (9/11). No decrease was found in the frequency of contamination of PBSCs compared with BM. In one patient, quantitative competitive PCR (C-PCR) identified a three- to tenfold greater quantity of contamination in the BM compared with PBSC. All evaluated patients (6/6) with contamination prior to BMT had persistence of marrow contamination following BMT. Our data demonstrate that TSO-PCR can generate a molecular marker for the majority of patients with intermediate- and high-grade NHL. In addition, we identified a high rate of occult lymphoma involvement in both BM and PBSC. As demonstrated by C-PCR, however, quantitative differences may exist in contamination of BM and PBSCs.

Base Sequence↗
PubMed1991

Laparoscopic common bile duct exploration.

Operative common bile duct exploration, performed in conjunction with cholecystectomy, has been considered the treatment of choice for choledocholithiasis in the presence of an intact gallbladder. With the advent of laparoscopic cholecystectomy, the management of common bile duct stones has been affected. More emphasis is being placed on endoscopic sphincterotomy and options other than operative common duct exploration. Because of this increasing demand, we have developed a new technique for laparoscopic common bile duct exploration performed in the same operative setting as laparoscopic cholecystectomy. A series of five patients who successfully underwent common bile duct exploration, flexible choledochoscopy with stone extraction, and T-tube drainage, all using laparoscopic technique, is reported. Mean postoperative length of hospital stay was 4.6 days. Outpatient T-tube cholangiography was performed in all cases and revealed normal ductal anatomy with no retained stones. Follow-up ranged from 6 weeks to 4 months, and all patients were asymptomatic and had normal liver function tests.

Adolescent↗
PubMed1990

Restructuring support staff classification levels for academic health sciences library positions.

Nonprofessional library support staff traditionally hold what are considered to be low-paying, nonchallenging positions. These negative factors make retaining creative and productive employees difficult. This article outlines the approach taken at the Medical College of Georgia's Robert B. Greenblatt, M.D. Library to devise a structure of library staff positions that becomes progressively more demanding. A new nine-level Library Staff Classification Plan resulted. This plan also enables and encourages employees to acquire more skills and to accept more responsibility in order to qualify for higher-level library positions or to advance their present position to receive comparable rewards. The plan expresses the level of responsibilities expected, the employee qualifications desired, and lists representative duties across the spectrum of typical library tasks.

Georgia↗
PubMed1988

In vitro cytotoxicity of recombinant ricin A chain-antitransferrin receptor immunotoxin against human adenocarcinomas of the colon and pancreas.

The sensitivity of three human colon adenocarcinoma cell lines (LoVo, LS174T, and SW1116) and a human pancreatic adenocarcinoma cell line (Hs766T) to a recombinant ricin A chain-antitransferrin receptor immunotoxin was studied. In addition, the carboxylic ionophore monensin was used in conjunction with the immunotoxin to determine the possibility of increased cytotoxicity without loss of specificity. The immunotoxin, 454A12-rRTA, is composed of the monoclonal antibody 454A12 directed against transferrin receptor and of ricin A chain, which was produced by recombinant DNA techniques. In 18 h dose-response cytotoxicity assays, the median inhibitory dose (ID50) against LoVo, LS174T, and SW1116 was found to be 3 X 10(-10), 3.6 X 10(-11), and 3.6 X 10(-10) M, respectively; in the same assay, the ID50 for Hs766T was found to be 4 X 10(-10) M. In the presence of monensin, the ID50 for the adenocarcinoma cell lines was reduced 9-fold, 28-fold, and 5-fold, respectively. In cytotoxic kinetic assays, 50% of control protein inhibition was reached in immunotoxin-treated LS174T cells 12-fold faster in the presence of monensin than in its absence. Immunotoxin-treated LoVo cells reached 50% inhibition of control protein synthesis fivefold faster in the presence of monensin than in its absence. Furthermore, no toxicity of immunotoxin or potentiation by monensin was observed in either a control cell line (Swiss albino mouse 3T6) treated with specific immunotoxin or with a control immunotoxin assay. These results show the in vitro specificity and selectivity of 454A12-rRTA immunotoxin for human gastrointestinal and pancreatic cancer cell lines.

Adenocarcinoma↗
PubMed1976

A technique for estimating life expectancy with crude vital rates.

This paper describes a method of estimating life expectancy at birth on the basis of crude vital rates. The method is derived from stable population theory and it furnishes good estimates insofar as the current crude vital rates of a population are close to its intrinsic rates. This condition is generally met in closed populations which have not experienced sharp movements in fertility. The method is useful for estimating life expectancy in developing nations with good sample registration systems but for which information on age is of poor quality. It is also useful for estimating the movement of life expectancy in certain European nations in the period prior to regular census taking. There are a number of nations and regions in Europe for which long series of birth and death rates are available but for which census age counts are widely spaced.

Birth Rate↗