Search PubMed⌕ Search

Biomedical subjects

S Mitchell

Publications and source records attributed to S Mitchell.

At least 163 records · Page 9Linked to original sources
PubMed1988

Cadaveric renal transplantation at the University of Pittsburgh: a two and one-half-year experience with the point system.

From January 1, 1986 to July 30, 1988, 530 consecutive cadaver kidney transplantations were performed with patient selection by a point system that took into account time awaiting an organ, donor-recipient matching, degree of presensitization, and some less important factors. The effect of the system was to diminish judgmental factors in case selection which in the past, had probably operated to the disadvantage of "undesirable" potential recipients, including older ones. Primary 1-year graft survival (74%) and graft survival after retransplantation (71%) were lower than in the earlier time. However, the results with triple-drug therapy using CsA, AZA and P demonstrated 88% 1-year graft survival for primary graft recipients and 74% in highly sensitized patients, with comparable patient mortality. These latter observations provide some assurance that the concepts of equitable access and efficient utilization of a scarce resource are not mutually exclusive.

Actuarial Analysis↗
PubMed1988

A liver transplant center information management system.

A comprehensive microcomputer-based data management system has been developed to facilitate candidate selection and to track clinical performance for the liver transplant program at the University of Pittsburgh. A relational database manager, dedicated statistical analysis software, and presentation graphics are all elements that have been integrated into the system.

Humans↗
PubMed1987

Synthetic peptide immunoassay distinguishes HIV type 1 and HIV type 2 infections.

Efforts to solve the epidemiologic puzzle of AIDS in Africa are complicated by the presence of multiple human retroviruses. Simple serologic tests that unambiguously distinguish among infections by these retroviruses are essential. To that end, a partially conserved immunoreactive epitope was identified in the transmembrane glycoproteins of human immunodeficiency viruses (HIV) types 1 and 2. Synthetic peptides derived from these conserved domains were used in sensitive and specific immunoassays that detect antibodies in sera from patients infected with HIV-1 or HIV-2. By making single amino acid substitutions in the HIV-1 peptide, it was possible to demonstrate HIV-1 strain-specific antibody responses to this epitope. Such custom-designed peptides synthesized from this domain are likely to detect newly discovered HIV types, define infection with specific HIV strains, and allow detection of group-common antibodies.

Amino Acid Sequence↗
PubMed1987

Evaluation of balloon angioplasty of coarctation restenosis by magnetic resonance imaging.

Eight patients treated by balloon angioplasty for coarctation restenosis have been followed for 4 to 54 months (mean 40) by physical examination using Doppler pressures and by magnetic resonance imaging in a superconducting magnet operating at 0.6 tesla. Image analysis was performed by inspection and by measurement of the aorta, with particular attention to the angioplasty site and its relation to the ascending aorta at the same axial level. Similar measurements were made from immediate postangioplasty angiograms. Residual pressure gradients were 0 to 12 mm (mean 2), reflecting persistent absence of a gradient in 1 patient and further gradient reduction in 7. Images showed no aneurysm formation, mild residual or recurrent stenosis in 4 patients, minimal focal periaortic soft tissue thickening in 1 patient and an interval increase in the ratio of ballooned segment diameter to ascending aortic diameter in the 7 patients in whom it could be measured. Thus, intermediate-term results of balloon dilatation of coarctation restenosis are excellent and magnetic resonance imaging is well suited to the serial studies required in these patients.

Angioplasty, Balloon↗
PubMed1987

Gender and symptoms of depression and anxiety among Kikuyu secondary school students in Kenya.

Numerous studies have confirmed that patterns of mental illness are influenced by sociocultural factors such as socioeconomic status and gender. This study describes the patterning of symptoms of depression and anxiety on a 20 item self-report questionnaire, the Health Opinion Survey, completed by 159 Kikuyu secondary school students in Kenya. Significant quantitative differences in the responses of males and females to seven of the questions were found, including females reporting more depression symptoms than males. These results are compared to an earlier study of 116 Kikuyu adults in which the differences between males and females were greater. This paper contributes to the literature on the relationship between gender and depression while adding to the sparse descriptive literature on symptoms of depression and anxiety in normal African populations.

Adolescent↗
PubMed1987

Percutaneous management of benign ureteral strictures and fistulas.

The percutaneous methods of management of benign ureteral strictures or fistulas have developed as a natural evolution of percutaneous nephrostomy and angiographic techniques. We review our 5-year experience, which includes 18 patients with 19 benign ureteral strictures and 12 patients with ureteral fistulas. In the majority of the patients the ureteral strictures occurred at sites of surgical reconstruction or endoscopic manipulation. All fistulas resulted from surgical injury. In 10 of the 12 patients (82 per cent) the fistulas healed without development of a stricture or need for further intervention. Patients with short ureteral strictures had a high incidence of success and they usually were the best candidates for percutaneous manipulation. The long strictures usually were of longer duration and they were less likely to be managed successfully percutaneously. Failure of percutaneous dilation did not impede subsequent surgical management. Percutaneous management often is a reasonable initial step in the treatment of ureteral strictures and fistulas.

Dilatation↗
PubMed1987

Changes in treatment-related concepts of illicit drug abusers related to time in treatment in two residential treatment programs.

This research investigated the effects of two residential drug treatment programs on changing the attitudes the residents had toward three treatment-related concepts over a 10-month time period. The semantic differential evaluative and potency scales of the concepts Therapeutic Community, Counselor, and Group Therapy were administered to the residents of these programs after they were residents for set periods of time. The results of this research showed that the residents rated the evaluative and potency scales of Group Therapy and Counselor higher the longer they remained in the program.

Adult↗
PubMed1987

Kidney transplantation in Pittsburgh: experience and innovations.

1. The introduction of combined CsA and steroid treatment as the baseline immunosuppressive medication significantly enhanced the results of kidney transplantation in our series. But various other preexisting recipient or donor conditions may still have an important effect on kidney transplant survival and should not go unrecognized. 2. Living-related kidney transplants were almost totally abandoned at our institution. Reasons for this approach are the increased availability of cadaveric donor organs, the improved results with cadaveric transplants under CsA and the possible risks to the living donors. 3. Combined liver/kidney transplants have been shown to offer a favorable treatment modality for patients with endstage liver and renal failure. 4. A newly developed center-oriented Transplant Information Management System (TIMY) significantly facilitates the clinical and research tasks in our department. 5. An integrated, computerized scoring system for equitable allocation of donor organs has proven to be highly effective during routine clinical use.

Adolescent↗
PubMed1986

Subpopulations of common acute lymphoblastic leukemia antigen-positive lymphoid cells in normal bone marrow identified by hematopoietic differentiation antigens.

Bone marrow samples from normal adults and children with nonhematologic malignancies not involving the marrow, acute lymphoblastic leukemia (ALL) in continued remission, and immune cytopenias were studied by two-color immunofluorescence (IF) and flow cytometry to characterize common acute lymphoblastic leukemia antigen (CALLA)-positive marrow lymphoid cells. Marrow was separated by Ficoll/Hypaque centrifugation followed by passage over a monoclonal antibody affinity column to remove myeloid cells prior to IF staining. A higher proportion of CALLA-positive cells was found in the pediatric marrows (mean, 33.7% +/- 6.3% SEM) than in the adult marrows (mean, 4.5% +/- 1.6% SEM). Two subpopulations of CALLA-positive cells identified by cell sorting to be of lymphoid morphology were found in both adult and pediatric marrows. A small subpopulation comprising 12.3% of the total CALLA-positive cells was characterized by a high intensity of CALLA, terminal deoxynucleotidyl transferase (TdT), and MY10 expression, but low B1, common leukocyte antigen, and peanut agglutinin receptor expression. The remainder of the CALLA-positive cells displayed low intensity of CALLA expression, positivity for the common leukocyte antigen, B1 and peanut agglutinin, and negative reaction with TdT and MY10. Both CALLA-positive subpopulations were positive for HLA-DR and the pan-B cell marker B4, but negative for cytoplasmic immunoglobulin, B2 and Leu 1. BrdU labelling studies showed that a similar proportion of cells in each subpopulation was in S phase. A slightly higher proportion of the strongly CALLA-positive cells possessed the morphologic features of high nuclear/cytoplasmic (N/C) ratio and prominent nucleoli. These studies suggest that a discrete maturation step occurs among CALLA-positive marrow lymphoid cells, resulting in the loss of TdT and MY10 expression, but gradual acquisition of the B cell marker B1 and the common leukocyte antigen. The presence of B4 antigen in nearly all CALLA-positive cells suggests that both subpopulations of normal CALLA-positive marrow cells are committed to the B cell lineage.

Adult↗
PubMed1985

Abbreviated surveillance of nosocomial urinary tract infections: a new approach.

An abbreviated method for the surveillance of nosocomial urinary tract infection is described. Combining desirable features of both active and passive surveillance, this new method involves concurrent review of microbiology reports. Compared to traditional active surveillance methods which require review of individual patient charts, the abbreviated method requires only one-fifth the time commitment while maintaining a 98% sensitivity. Although some degree of overestimation is inherent in this method, the primary goals of surveillance--monitoring infection rates and identifying clusters of infection--should be preserved.

Cross Infection↗
PubMed1985

Storing summary patient data as a microcomputer file.

The time taken to summarize 1000 patient records and store this data as a hard disc file on a microcomputer was evaluated in a health centre with about 7300 patients. On average it took 25 minutes to prepare or update summary sheets for each patient and between three to five minutes to input the data to the computer. About one in 10 of the records were long and complicated and took considerably more time to summarize. An error rate of 9% over six months was determined for the age-sex register, mostly owing to patients who had left the practice. In about 5% of cases important information was missing from the A4 folders and was only obtainable from the health visitor records.

Computers↗
PubMed1984

Prevalence of antibodies to lymphadenopathy-associated retrovirus in African patients with AIDS.

The presence of antibodies to lymphadenopathy-associated retrovirus (LAV) was determined by a radioimmunoprecipitation assay and by an enzyme-linked immunosorbent solid assay of sera from Zairian patients with the acquired immune deficiency syndrome (AIDS) in 1983. Thirty-five of 37 patients (94 percent) and 32 of 36 patients (88 percent), respectively, were seropositive by the two tests. In a control group of 26 patients, six (23 percent) showed positive results in these tests. Of these six control patients, five had clinically demonstrable infectious diseases and a low ratio of T4 to T8 lymphocytes. In addition, sera collected from a control group of Zairian mothers in 1980 were positive for LAV in 5 of 100 cases. Other serologic data suggest that LAV was present as early as 1977 in Zaire.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Effects of female urine on growth and sexual maturation in male rabbits.

Urine of adult males or adult females, or distilled water (control), was applied to the oro-nasal grooves of Dutch-belted male rabbits after weaning. The body and testicular weights of males treated with urine of females were significantly less than those of controls between 88 and 125, and 96 and 109 days, respectively. Sperm counts and the pattern of androgen-dependent production of gel-plugs in semen also differed significantly between treatments during the critical maturation period. These suppressant effects of urine of females on male development in rabbits may represent a mechanism by which females may manipulate the reproductive success of neighbouring conspecifics in free-living colonies.

Animals↗