PubMed Health⌕ Search

Biomedical subjects

F Quinn

Publications and source records attributed to F Quinn.

24 records · Page 2Linked to original sources

Neuroblastoma--a surgical perspective.

The role of an aggressive surgical policy in the management of neuroblastoma (NBL) was examined in a retrospective study from a total of 57 patients presenting to a single institution between 1979 and 1989. Surgery consisted of either primary excision of tumour or elective resection following intensive chemotherapy. Two year disease-free survival (DFS) for the entire group was 100% for Stage I patients (n = 2), 86% for Stage II (n = 7), 55% for Stage III (n = 11), 12% for stage IV (n = 33) and 50% for stage IVs (n = 4). In all long-term survivors, surgical excision of primary tumour had been achieved. Elective surgery of primary tumour was not performed in six patients with Stage IV disease; median survival for these patients was eight months compared with 19 months for those other patients with Stage IV disease who did have surgery +/- high dose melphalan and autologous bone marrow rescue. Postoperative complications were documented in 13 of 48 operated patients (27%), emphasising the technical challenges encountered in resection of NBL. Age at presentation and site of primary tumour were major factors affecting prognosis: patients who presented < 1 years of age (n = 15) achieved 80% DFS, > 1 year and < 2 years (n = 12), 33%, and > 2 years (n = 30) 13%; 10 of 11 patients (91%) with primary supradiaphragmatic disease are alive and well compared with 10 out of 46 (22%) with infradiaphragmatic disease (P = 0.01). Based on the experience from this centre, it would appear that surgery can be curative for patients with Stage I, II and III disease but can only, at best, prolong DFS for Stage IV patients. Alternative therapeutic strategies are indicated for this latter group of patients.

Abdominal Neoplasms↗

Cytopathogenic effects in enterocytelike Caco-2 cells differentiate virulent from avirulent Listeria strains.

We have developed a simple test that differentiates between virulent and avirulent Listeria species as defined by the mouse 50% lethal doses (LD50S). The assay is based on trypan blue-revealed cytopathogenic effects that are produced during the infection of the human enterocytelike cell line Caco-2. These effects were elicited only by Listeria strains that had an intraperitoneal mouse LD50 less than 10(8) and were not produced by nonhemolytic, avirulent strains of Listeria monocytogenes generated spontaneously or by Tn916 mutagenesis or by avirulent Listeria species. A negative test was also obtained with hemolysin-producing, avirulent L. monocyotogenes NCTC5105 and Listeria ivanovii KC1786. The test was negative with avirulent L. monocytogenes strains which are strong inducers of opacity in egg yolk agar. However, a strain which has a low LD50, such as 10(4), may show less severe cytopathogenic effects than a strain having a higher LD50, such as 10(6). The test has been effectively used to screen for virulent listerial isolates, spontaneous mutants, and transposon-induced mutants.

Animals↗

French angles: a simple aid to neurodevelopmental examination.

"French angles" are the amplitude of passive movement at a single joint, which can be easily measured using a goniometer, and reflect the lengthening capacity of muscles--a component of passive tone. Fifty infants aged 1-52 weeks had their "French angles" measured by non-expert examiners using a plastic goniometer. All the angles measured, except ankle dorsiflexion, increased in a predictable, linear fashion from birth to one year of age. Thus in normal term infants passive tone gradually relaxes from birth to the age of one year. Three additional infants with known neuromuscular disorders were found to have angles outside the obtained normal range. The babies with cerebral palsy had reduced adductor angles reflecting adductor spasm, and the baby with Werdnig Hoffman syndrome had an increased adductor angle reflecting increased adductor extensibility. The results provide a quantitative measurement of neurological maturation during infancy, and should complement the routine neurodevelopmental assessment. The method proved quick, simple and reliable, and may become useful as a screening test for neuromuscular disorders.

Biomechanical Phenomena↗

Characterization of the T, L, I, S, M and P cell surface (immobilization) antigens of Tetrahymena thermophila: molecular weights, isoforms, and cross-reactivity of antisera.

In the ciliate protist Tetrahymena thermophila the L, H, T, I, S, M and P cell surface proteins (immobilization antigens) are expressed under different conditions of temperature (L, H, T), culture media (I, S), and mutant genotype (M, P). Immunoblot and autoradiographic studies using antisera to purified protein show that the molecular weights of these proteins range from 25,000 to 59,000. The H, T, S, M and P antigens are recognized as single polypeptides, whereas L, I, and one allelic form of T each appear to consist of a family of polypeptides. Although antisera are specific in immobilization and immunofluorescence assays of surface protein in living cells, cross-reactivity is seen with denatured protein on immunoblots. It is hypothesized that the surface protein genes are organized into families of evolutionarily related isoloci.

Animals↗