Teaching social responsibility: the Manhattan project. Commentary on "The Six Domains of Research".

This paper discusses the critical necessity of teaching students about the social and ethical responsibilities of scientists. Both a university scientist and a middle school science teacher reflect on the value of teaching the ethical issues that confront scientists. In the development of the atomic bomb in the US-led Manhattan Project, scientists faced the growing threat of atomic bombs by the Germans and Japanese and the ethical issues involved in successfully completing such a destructive weapon.

Ultrasonography of the rotator cuff: Analysis of results in a community setting.

Forty-six patients underwent ultrasonogrophy evaluation of their shoulder for suspected rotator cuff tears from 1989 to 1992. All ultrasound studies were evaluated by a radiologist (HJH) who was not subspecialty-trained in shoulder ultrasonography. All patients had surgical confirmation of the status of their tendons.

Surgical management of recurrent nasopharyngeal carcinoma after radiation failure at the primary site.

Nine patients have undergone transpalatal resection of recurrent nasopharynx cancer 10 to 56 months following a full course of external beam irradiation. Seven patients were treated for cure, and two were treated palliatively because of nasal airway obstruction, recurrent epistaxis, and severe headaches. Of the patients treated for cure, five are living free of disease 6 to 48 months (mean, 22.

The "diff-if". Use of microcomputer analysis to triage blood specimens for microscopic examination.

Increasingly, all automated blood counts are not accompanied by a microscopic white blood cell differential. A popular strategy is to obtain a manual differential if any part of the automated blood count and differential is outside specified limits (the "diff-if" strategy). The authors compared two sets of criteria to triage blood counts for manual differentials: previously recommended numeric values, and the analysis of a microcomputer program.

Trichloroethylene biodegradation by a methane-oxidizing bacterium.

Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotrophic bacterium, degraded TCE if grown on methane or methanol, producing CO(2) and water-soluble products.

A solution to declining autopsy rates--the Decedent Affairs Office.

Can the decline in autopsy rates be reversed by solving logistical problems that impede or deter permissions and arrangements? The authors report an increase in the autopsy rate at their institution after a Decedent Affairs Office was established. Furthermore, the time between death and autopsy has been greatly narrowed, thus providing optimal tissue for diagnosis. As an additional benefit, the number of organ donations has also risen.

Computerized tomographic analysis of acute calcaneal fractures.

Computerized tomography (CT) of the hindfoot is introduced as an effective technique in the evaluation of acute, intra-articular calcaneal fractures. Thirty-two fractures in 30 patients have been reviewed, and common fracture characteristics identified. These included the presence of a sustentacular fragment, displacement and comminution of the lateral weightbearing surface, and lateral spread with loss of calcaneal height.

Membrane-reconstituted, purified H-2Kb specifically inhibits T-cell-target cell conjugate formation.

We report the use of a sensitive microassay to detect purified H-2Kb antigens which have been functionally reconstituted into membrane vesicles of defined composition. The histocompatibility antigens have been purified by monoclonal antibody affinity chromatography. The assay utilizes inhibition of specific conjugate formation between allogeneically primed (H-2d anti- H-2b) cytotoxic T cells and H-2b target cells by the membrane-reconstituted H-2Kb antigens.

Use of mean platelet volume improves detection of platelet disorders.

Classification of platelet disorders has been based on the platelet count. Addition of a second variable, mean platelet volume (MPV), to the routine blood count allows classification of patients into 9 categories: high, low, or normal MPV, and high, low or normal platelet count. We studied 1,244 adult inpatients.

Differential recognition and lysis of EL4 target cells by cytotoxic T cells: differences in H-2Kb antigenic density and cytoskeletal proteins.

Direct binding of 125I-iodinated anti-H-2Kb monoclonal antibody (B8-24-3) to EL4 cells indicated a similar association constant but a 2.7-fold higher H-2Kb antigenic density when the EL4 cells were grown in ascites (2.0 X 10(5) sites/cell) than in tissue culture (7.

Wheat germ agglutinin-resistant variant of EL4 containing altered oligosaccharides as a target cell for cytotoxic T cells.

A lectin-resistant variant of the murine EL4 lymphocytic leukemia cell line was selected in the presence of wheat germ agglutinin for low levels of cell-surface sialic acid. H-2Kb was the major internally radiolabeled H-2b molecule on the cell-surface of WD1, and it was not sialylated, as determined by two-dimensional gel analysis. Endo-beta-N-acetylglucosaminidase H treatment of the WD1 membrane fractions suggested that the oligosaccharides on the cell-surface H-2Kb molecule were complex, but nonsialylated.

Improved classification of anemias by MCV and RDW.

New automated blood cell analyzers provide an index of red cell volume distribution width (RDW) or heterogeneity and a histogram display of red cell volume distribution. We have developed a classification of red cell disorders, based on mean corpuscular volume (MCV) or red cell size, heterogeneity, and histograms, to guide diagnosis from the peripheral blood analysis. The distinction of iron deficiency anemia from heterozygous thalassemia or the anemia of chronic disease and the detection of early iron and folate deficiency is improved.

Platelet size in health and hematologic disease.

In normal subjects, mean platelet volume (MPV) has an inverse, nonlinear relation with platelet count, while platelet volume heterogeneity has a direct, nonlinear relation with MPV. Compared with the reference range established for normal subjects, patients with chronic lymphocytic leukemia, atherosclerotic heart disease, diabetes mellitus, and chronic undifferentiated schizophrenia had normal platelet volume mean and heterogeneity. Patients treated with cytotoxic chemotherapy for acute nonlymphocytic leukemia, patients with megaloblastic anemia, and patients with aplastic anemia had abnormally small platelets with increased heterogeneity.

Physical separation and biochemical characterization of H-2b-encoded proteins on target cell plasma membranes and endoplasmic reticulum.

Plasma membranes and endoplasmic reticulum were purified on the basis of their physical properties, and their identity was confirmed by membrane marker activities. Comparative adsorption analysis indicated that plasma membrane and endoplasmic reticulum vesicle fractions adsorbed 25% and 5%, respectively, as much anti-D6 alloantiserum as intact cells. Two-dimensional gel analyses of immunoprecipitates of the H-2b-encoded proteins from the EL4 tumor cell line indicated a series of proteins containing complex carbohydrates in the plasma membrane and two additional N-asparagine-linked proteins in the endoplasmic reticulum.

Mean platelet volume. The inverse relation of platelet size and count in normal subjects, and an artifact of other particles.

We measured whole-blood mean platelet volume (MPV) and platelet count, determined by the Coulter Counter model S-Plus, in 683 normal subjects. There was nonlinear, inverse relation between MPV and platelet count throughout the normal range of platelet count: the change in MPV was most pronounced at the lower platelet counts. Because of this non-linear relation, "platelet-crit," the product of platelet count and MPV, was not constant, but varied directly with platelet count.

The status of methods of calibration in hematology.

Three years ago, the authors described methods for calibration and quality control of Coulter automated hematology instruments. These and other methods have received fairly widespread use in hematology laboratories. The effectiveness of such use was tested through special questionnaires conducted by the College of American Pathologists in 1978.

Cellular mechanisms of prostaglandin action.

The human platelet and erythrocyte differ quite dramatically in relation to the arachidonic acid cascade. The platelet synthesizes its own characteristic products, while the erythrocyte lacks cyclo-oxygenase activity but possesses other metabolic enzymes. In these and other cell types the metabolites are potentially determined by the cascade enzymes, the availability of cofactors, the presence of specific activators and inhibitors, and the selective binding or transport of intermediates.

Inhibition of specific effector T cell-target cell conjugates by cell plasma membranes.

Conjugate formation between effector T cells raised in vivo in a BALB/c hose had fluorescein diacetate-labeled allogeneic EL4 tumor target cells was observed and scored by using a fluorescence mirroscope. This conjugate formation was found to be specifically inhibited by plasma membrane vesicles isolated from the EL4 cells.