Salmonella infections in patients with acquired immunodeficiency syndrome

Salmonella infections occurred in six patients with acquired immunodeficiency syndrome (AIDS) and one patient with probable AIDS. The immune system defects increase the susceptibility of patients with AIDS to salmonella infections. Recognition of salmonellosis in patients with AIDS is important because of a high propensity of this organism to invade the bloodstreams of these patients, and because, unlike other infections in patients with AIDS, this infection can be easily treated.

The dorsal tegmental nucleus: an axoplasmic transport study

The afferent and efferent connections of the dorsal tegmental nucleus (DTN) were studied in the rat using axoplasmic transport techniques. Horseradish peroxidase (HRP) and Fast Blue were injected stereotaxically into either pars centralis or pars ventromedialis of the DTN, two subdivisions of the nucleus with distinctive connections. The pars centralis is reciprocally connected with the ipsilateral lateral mammillary and interpeduncular nuclei; these projections constitute the major afferent and efferent systems of the DTN. Commissural fibers from the corresponding pars centralis and intrinsic fibers systems are massive and form a complex fiber meshwork within the subnucleus. The prepositus hypoglossi nucleus (ipsilateral) and supragenualis nuclei (bilateral) also project to the pars centralis. Smaller numbers of afferent fibers arise from the lateral habenular nucleus, the posterior hypothalamus and the brainstem reticular formation. The pars ventromedialis of the DTN receives diverse inputs which include the septal nuclei, diagonal band of Broca, preoptic area, anterior and lateral hypothalamus, lateral and medial habenular nuclei, medial mammillary nucleus and many nuclei of the brainstem reticular formation. Based on the differences of connections and cytoarchitecture between the pars centralis and the pars ventromedialis, the pars ventromedialis may be an entity separate from the dorsal tegmental nucleus.

Antitumor activity of esorubicin in human tumor clonogenic assay with comparisons to doxorubicin

The new anthracycline analog, esorubicin (4'deoxy-doxorubicin, ESO), was tested against fresh biopsies of human solid tumors in vitro in clonogenic assay and the results were contrasted to those obtained with doxorubicin (DOX). ESO appeared to be significantly more potent on a weight basis than DOX in these studies, and exhibited a spectrum of antitumor activity in vitro that was in general qualitatively similar to that observed with DOX. In vitro antitumor activity was observed in a wide variety of human cancers including anthracycline-sensitive tumor types. ESO has previously been reported to have decreased cardiac toxicity in preclinical models as compared to DOX. Comparative testing of these anthracyclines on granulocyte-macrophage colony-forming units (GM-CFUs) and tumor colony forming units (TCFUs) indicated that the in vitro GM-CFU assay is more sensitive to these myelosuppressive drugs than are TCFUs, and underscores the need for in vivo studies to determine normal tissue toxicity and the therapeutic index of a drug. Early results of phase I studies suggest that with respect to myelosuppression, the maximally tolerated dose of ESO will be about half that of DOX. The increased in vitro antitumor potency observed for ESO and a spectrum of activity (even at one half the dose of DOX) supports the broad testing of ESO in the clinic to determine whether it will prove to be a more effective and less toxic anthracycline.

Detection of IgG in supernatants of pokeweed mitogen-stimulated human lymphocyte cultures by one step solid-phase radioimmunoassay (SPRIA)

A one step solid phase radioimmunoassay is used as a simple and reproducible method of detection and quantitation of IgG produced by human PBL after stimulation with PWM. Modifications of culture conditions are necessary to make culture supernatants suitable for this assay. Pulsing with PWM must be performed in serum-supplemented culture medium for 4-5 days. After thorough washing, medium is then replaced with serum-free medium. Under these conditions, synthesis and secretion of IgG continues for at least 9 days. The amount of IgG produced by 10(6) normal adult PBL as detected in this system is 0.77 +/- 0.47 micrograms. No close correlation between cell proliferation and IgG synthesis was observed.

A hypo-osmotic medium to disaggregate tumor cell clumps into viable and clonogenic single cells for the human tumor stem cell clonogenic assay

A hypo-osmolar medium and tissue processing technique is described which is useful for disaggregation of residual human tumor cell clumps persisting after mechanical or enzymatic treatment of solid tumors and malignant effusions. The addition of the hypo-osmolar procedure to the standard methods for disaggregation increased the viable single cell yield in solid tumors by 47% and in malignant effusions by 67%. In 5 of the 26 solid tumor specimens tested in the human tumor stem cell assay, clonogenic single cells were obtained with the hypo-osmolar procedure, whereas no growth was observed using standard methods. Overall, the success rate for clonogenicity increased from 46% to 65% for the 26 solid tumors, with the major improvement occurring in ovarian cancer. Clonogenicity was obtained in 80% of malignant effusions both by standard methods and the hypo-osmolar techniques. The increased total yield of clonogenic cells obtained with this procedure enhances the opportunity for experimental versatility and in vitro drug testing.

Usefulness of abrin as a positive control for the human tumor clonogenic assay

A series of approaches were tested in order to develop a simple technique for introducing a routine positive control into the Human Tumor Clonogenic Assay. Of the various techniques tested, the best proved to be the addition of the toxic plant lectin abrin to the culture system. When added to the agar underlayer of the culture system so that the final abrin concentration in culture was 10 micrograms/ml, survival of human tumor colony-forming units (TCFU) was reduced to less than 1% of control in 16/34 (47%) of human tumors, to less than 10% in 33/34 (97%) and to less than 30% in all tumors tested (100%). A clear dose-response relationship to fractional survival was observed for individual tumors tested at multiple dose levels of abrin. When the dosage of abrin was reduced to 1 micrograms/ml, survival of TCFU was reduced to less than 30% in 25/28 (89.2%) of experiments. Inclusion of abrin controls in clonogenic assays thus provides an excellent and reproducible positive control to which cytotoxic effects of a variety of therapeutic agents can be compared.

Direct "wet" staining of tumour or haematopoietic colonies in agar culture

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