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Biomedical subjects

K Mayer

Publications and source records attributed to K Mayer.

252 records · Page 14Linked to original sources
PubMedDate not supplied

A computer system designed for a hospital transfusion service.

A computer system that enhances the efficiency of a hospital transfusion service is described. It reduces the possibility of clerical errors; shortens the time elapsed between the ordering and the delivery of blood products; decreases the outdating of these units; and provides easy access to medical, demographic, and statistical information.

Blood Banks↗
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Hemolysis following platelet transfusions from ABO-incompatible donors.

Two hemolytic transfusion reactions related to isoagglutinins present in group O platelet concentrates are reported. The first, a severe reaction in a group A 10-kg patient, resulted from transfusion of 200 ml of plasma containing a hemolytic anti-A, titer 16, and an IgG anti-A, titer of 32,000. In the second case, a group B adult received between 50 and 70 ml of O plasma with a titer (16,000) of anti-B. This was followed by hemolysis of approximately 40 percent of the patient's red cell volume.

ABO Blood-Group System↗
PubMedDate not supplied

AIDS: has the problem been adequately assessed?

Epidemiologic inferences about the epidemic of acquired immunodeficiency syndrome (AIDS) are developed from three different sources: case-control studies, cohort studies, and national data on prevalence and incidence. Together these data imply that reducing the number of sexual partners may in itself provide little protection. Shifting to a "lower-risk" behavior will only be helpful if the cumulative risk of transmitting the virus can be reduced nearly to zero. However, if all members of a minimally affected population made such a shift, the benefit to that population could be dramatic. The emerging realization that latency periods are longer than was first thought implies that the epidemic could be much more severe than has been anticipated. Regional trends give no assurance that it has reached a peak, even in areas of highest prevalence. Much more work needs to be done to establish the actual role of saliva in transmitting HTLV-III because oral contagion has the greatest potential to spread the disease. Efforts to determine the latency period are crucial to predicting the future of the epidemic. Preventive measures--behavior modification and education--hold some hope of retarding spread of the epidemic pending development of effective therapy or a vaccine.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Case report: Antemortem diagnosis of central nervous system strongyloidiasis.

Strongyloidiasis is usually a benign illness confined to the gastrointestinal tract. However, dissemination (hyperinfection syndrome) may occur, particularly in patients with impaired cell-mediated immunity. The diagnosis of hyperinfection syndrome is often made postmortem, and mortality is high, even when the disease is recognized during life. Central nervous system involvement with Strongyloides stercoralis has previously been recognized in only a few cases at postmortem examination, and in one case antemortem. We describe a patient with disseminated strongyloidiasis in whom central nervous system involvement was diagnosed antemortem. This patient developed multiple bacterial and fungal systemic and central nervous system infections as a complication of disseminated strongyloidiasis. The natural history of the disease in man, factors predisposing to dissemination, immunologic aspects of helminthic infection, and treatment modalities are discussed.

Animals↗
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Calibration methods for measuring splenic sequestration by external scanning.

Conventional methods for measuring splenic sequestration of labeled cells rely on stationary probe counting over the liver and spleen. A quantitative spleen-scanning method is proposed as a means of performing a more accurate diagnosis of the degree of splenic sequestration. Improved methods for calibrating a rectilinear scanner employing "constant resolutions" collimators, designed for the in vivo measurement, are reported, Clinical evaluation of this method was performed by scanning several patients scheduled for splenectomy. Good correlation between in vivo and in vitro measurements of splenic radioactivity for 29 patients was obtained. A least-squares fit to the data yielded a coefficient of determination r2=0.93.

Chromium Radioisotopes↗
PubMedDate not supplied

Reality orientation training in an amnesic: a controlled single-case study (n = 572 days).

'Reality orientation training' (ROT) is a well-established therapy used with the elderly, especially those with dementia. It aims to improve orientation and reduce negative behaviours, e.g. confusion. ROT has been recommended for non-demented patients with acquired neurological impairment. However, this suggestion has not been investigated further in controlled trials. This paper describes an informal 24 h ROT programme with an amnesic subject (H.J.). It combined single-case experimental designs derived from behaviour therapy. Target behaviours were items of temporal orientation--current time/time of day, year, season, month and day of week. Orientation regarding the current date was not trained, and thus served as control variable for non-specific effects (e.g. spontaneous recovery). In order to improve oriented behaviour in different relevant situations outside the clinic, we chose 24 h ROT instead of formal therapeutic sessions. The patients' spouse offered 24 h ROT at home 7 days a week. This consisted of reminding the patient of orientation information, e.g. the current day of the week in different situations. Furthermore, negative behaviours such as irrelevant questions were ignored. The patients' spouse was trained and supervised to carry out this task in 27 sessions each lasting 10 min. For 14 weeks supervision was provided twice a week in the clinic (i.e. 2 x 10 min). Afterwards the spouse continued to apply ROT at home without further supervision in two follow-up periods. As expected, learning was slow but reliable. Generalization of improvement to another setting was shown (home vs clinic). Stable therapeutic gains over a long follow-up period could be demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMedDate not supplied

Immune responses to a recombinant human immunodeficiency virus type 1 (HIV-1) gpl60 vaccine among adults with advanced HIV infection. Massachusetts gp160 Working Group.

OBJECTIVE: To assess immunogenicity of recombinant human immunodeficiency virus type 1 (HIV-1) envelope vaccine (rgp160) in late HIV infection. STUDY DESIGN/METHODS: HIV-infected volunteers (n = 142), with CD4+ T lymphocyte counts of <400/mm3, were enrolled in a dose-comparison, open-label trial with stratification by CD4+ cell count, randomization to a primary series at two dose levels, and a sub-group receiving interferon-gamma (IFN-gamma) as an adjuvant. Subjects received booster doses of vaccine over a follow-up period of 18-28 months. RESULTS: At 6 and 12 months, 36% and 38% of participants, respectively, had new or augmented antibody titers (> or =4-fold increase) against one or more gpl60 epitopes (C1, V3, C41, 448C). Delayed-type hypersensitivity (DTH) to intradermal gpl60, initially not present in any participant, developed after immunization in 41%, with higher prevalence in participants receiving the lower dose of vaccine. Both antibody and skin test responses occurred in 20-25% of vaccine recipients. Virtually all antibody and skin test responses occurred in participants with initial CD4+ cell counts of >100 cells/mm3. IFN-gamma had no significant effect on immune response. Immunization was well tolerated. Trends in CD4+ cell count, clinical events, and laboratory findings correlated with baseline CD4+ T lymphocyte count stratum and not with immunization regimen. Opportunistic conditions occurred at expected rates. Viral load trends (p24 antigen in all participants and viral RNA by reverse transcription-polymerase chain reaction in a subset of 26 participants) did not correlate with immunization regimen. CONCLUSION: Immunization of patients with advanced HIV infection with rgpl60 resulted in new and augmented humoral and DTH responses, without unexpected significant adverse events or evident clinical benefits attributable to immunization.

AIDS Vaccines↗
PubMedDate not supplied

Endometrial stromal sarcomas--a retrospective analysis of 11 patients.

BACKGROUND: Endometrial stromal sarcoma (ESS) is a malignant tumour with its origin in the endometrial stroma. Little is known about the pathogenesis, risk factors, optimal therapy or outcome of this disease. PATIENTS AND METHODS: Eleven patients with ESS, treated between 1972 and 1996, are reported on. The hospital records of all the patients, including pathology and operative reports, were reviewed and information on treatment, recurrence and survival was obtained. RESULTS: The mean age of our patients was 56.6 years. The main symptom was abnormal vaginal bleeding. Most patients were diagnosed at FIGO stage I. Treatment modalities were surgery, radiation and, in one patient, chemotherapy. The median follow-up time was 42.1 months; 27.3% of the patients had local recurrence. The 1-year, 2-year and 5-year survival rates were 36.3%, 18.1% and 9.1%, respectively. CONCLUSION: ESS is a uterine sarcoma with a difficult differential diagnosis. Patients are frequently diagnosed in an early tumour stage but still experience local or distant recurrence. The prognosis is poor, with early recurrence and low long-time survival rates. The treatment includes surgery and adjuvant radiation, with endocrine therapy being a promising new approach. In order to obtain more information about the pathogenesis of the tumour and to find the optimal therapy, it is necessary that studies, even with small numbers of patients, are undertaken.

Adult↗
PubMedDate not supplied

Expression of alternatively spliced lck transcripts from the proximal promoter in colorectal cancer derived cell lines.

Ectopic expression of the lck gene has been demonstrated in epithelial tumor cells to be directed by the proximal promoter element. Variability of lck transcripts at the 5' end detected in T-cells and lymphoid malignancies prompted us to investigate the potential heterogeneity of lck mRNA molecules in colorectal cancer derived cell lines. Our experiments clearly indicate that the three different types of lck transcripts, which are exclusively derived from the proximal promoter, were expressed in our panel of colorectal cancer cells analyzed. DNA sequence analyses of the reversely transcribed lck mRNAs revealed that they indeed represented the lck transcripts designated type 1A, 1B and 1C, which have recently been identified in T-cells. Similarly with the situation in immature hematopoietic malignancies lck transcript 1B steady state levels were predominant in colorectal cancer derived cell lines. These findings lend further support to the notion, that expression of lck is part of anectopic lymphoid activation and differentiation program induced in these epithelial tumors.

Alternative Splicing↗
PubMedDate not supplied

Sexual violence against women living with or at risk for HIV infection.

OBJECTIVES: This study investigates factors associated with sexual violence against adult women living with and at risk for HIV infection. METHODS: Women at least 18 years old and living in Rhode Island or southeast Massachusetts enrolled from 1987 to 1992 in a cohort study of heterosexual HIV risk. A total of 408 women provided interviews on lifetime experiences of rape and HIV-related risk exposures. Data are presented on 96 women reporting experiences with rape as adults, and 231 women who reported never experiencing rape or forced sex. RESULTS: Lifetime prevalence of sexual abuse was 43%. Over half occurred during adulthood. Thirty-five percent of women with HIV were raped as adults. Among women with HIV, adult rape experiences were associated with earlier age of first sex, more sexual partners, unprotected sex involving drugs, earlier age of injection drug use, teen pregnancy, STDs, and serious gynecologic surgery than those reporting they were never raped (prevalence odds ratios ranged from 2.8 to 11.2). Among women without HIV, adult rape was associated with similar experiences, although with some exception, the relative odds estimates were less pronounced. Women engaged in sex work were more likely to report rape. CONCLUSION: The high prevalence of rape reported in this cohort of mostly economically poor women living with and at risk for HIV infection is consistent with other studies. Economic and social vulnerability that frames HIV risk and subsequent infection in women includes rape. Clinicians caring for women with HIV and counseling women at risk for infection need to screen routinely for sexual abuse.

Adolescent↗