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L Miles

Publications and source records attributed to L Miles.

29 records · Page 2Linked to original sources

Tumorigenic and metastatic properties of "normal" and ras-transfected NIH/3T3 cells.

To investigate the role of oncogene activation in the pathogenesis of malignant tumors, we have studied the tumorigenic and metastatic properties of NIH/3T3 secondary transfectants (designated A51) containing an activated c-Ha-ras-1 gene derived from the human T24 bladder carcinoma cell line and compared them with untransfected NIH/3T3 cells. Whereas subcutaneous implantation of NIH/3T3 cells in the supraclavicular region produced palpable tumors that failed to metastasize, NIH/3T3 cells inoculated in the footpad gave rise to malignant tumors that metastasized to the lung. Under identical conditions and irrespective of the site of implantation, A51 cells formed rapidly growing primary tumors that produced pulmonary metastases. In an assay for experimental metastasis, intravenously injected NIH/3T3 cells gave rise to pulmonary nodules only at high cell inocula and in long-term survivors (90 days after injection). In contrast, A51 cells formed multiple lung tumor colonies detectable 14 days after injection. These results indicate that "normal" untransfected NIH/3T3 cultures contain subpopulations of cells that express malignant properties and that transfection of NIH/3T3 cells with activated c-Ha-ras-1 accelerates formation of metastases.

Animals↗

Posttraumatic excessive daytime sleepiness: a review of 20 patients.

Twenty patients complaining of excessive daytime somnolence (EDS) secondary to significant head trauma were studied objectively. Several polygraphic recording protocols were performed over the 12-year study period. Eighteen of the 20 patients were objectively sleepy, 8 of them presented mixed sleep apnea syndrome that fragmented their sleep, 5 patients' sleep-related breathing problems improved over time, 9 patients presented daytime somnolence, and 1 reported abrupt bouts of muscle weakness and had two sleep onset rapid eye movement (REM) periods during daytime testing. Cerebrospinal fluid analysis for specific neurotransmitter metabolites' evaluation, pre- and postprobenecid, did not differentiate posttraumatic EDS patients from narcoleptics or other patients with EDS. Two patients (one with organic brain syndrome, the other depressed) reported subjective sleepiness, not confirmed by objective data. Objective testing in posttraumatic sleepiness is recommended because of the plurality of problems and medicolegal implications.

Adolescent↗

Circadian rhythm disturbances and sleep disorders in shift workers.

Employment which requires frequent shift rotation may lead to the development of specific sleep disorders. Delayed sleep phase (DSP) insomnia, a syndrome identified recently, can greatly impair an individual's circadian rhythm-dependent functions; it can occur when shift work disrupts normal sleep-waking schedules. Disorders of excessive daytime sleepiness, such as narcolepsy, occur in some subjects after they have been subjected to frequently rotating shifts. Understanding the problems associated with circadian rhythm disturbances and their interaction with sleep disorders is particularly important in industrial medicine; any clinician whose patients are subjected to frequent shift rotations should consider the effects of disrupted sleep-waking schedules.

Circadian Rhythm↗

Immune reactants in cryoproteins. Relationship to complement activation.

Cryoproteins were isolated from the serum of 5 patients with essential cryoglobulinaemia 5 patients with rheumatoid arthritis, and 2 patients with Sjøgren's syndrome. These cryoprecipitates contained IgG, IgM, and IgA as well as complement proteins C1q, C4, C3, and factor B. The cryoprecipitates were analysed further for content of antibody and antigen, and were tested for their ability to activate complement. In the cryoprecipitates of 2 patients with Sjøgren's syndrome, nuclear antigen and antinuclear antibody characteristic of an immunological specificity found in Sjøgren's syndrome were shown. The cryoprecipitates of 6 other patients contained rheumatoid factor and antibody to a lymphocyte nuclear antigen. The solubilized cryoprecipitates were tested by in vitro assays for their ability to activate complement by the classical or alternative pathways. All 12 cryoprecipitates activated the classical pathway. 9 of the 12 cryoprecipitates also activated the alternative complement pathway under conditions which did not involve activation of C1 and C4. These studies show that a high percentage of cryoprecipitates consist at least in part of immune reactants. We discuss the relationship of these findings to pathogenetic mechanisms in disease.

Aged↗