PubMed HealthSearch

Biomedical subjects

L A Knight

Publications and source records attributed to L A Knight.

17 recordsLinked to original sources

Higher-order factors assessed by the ISI and PRF.

The Interpersonal Style Inventory and the Personality Research Form were administered to 327 adolescents in order to test hypotheses with regard to the second-order factors that they share in common. The 37 scale scores were intercorrelated and factored by the principal axes method and rotated to an oblique solution. The seven correlated factors were interpreted as Impulse Control, Extraversion-Introversion, Autonomy, Level of Socialization, Achievement Motivation, Liking New Experience, and Adventure Seeking. These confirmed four of the hypothesized factors.

Achievement

Multiple karyotypic changes in retinoblastoma tumor cells: presence of normal chromosome No. 13 in most tumors.

There are conflicting reports on the frequency in retinoblastoma tumor cells of aberrations involving chromosome No. 13. To quantitate the frequency of various chromosome aberrations, we analyzed the karyotypes from the retinoblastoma tumors; all tumors contained chromosome abnormalities. Chromosome No. 13 was altered in only two tumors, but the aberrations in these two cases affected different portions of the chromosome. We have concluded that chromosome aberrations affecting chromosome No. 13 are relatively infrequent in retinoblastoma tumors. Chromosome No.1 was involved in rearrangements in eight tumors; in six tumors the rearrangements lead to trisomy of 1q25-1q32. Seven tumors had aberrations resulting in trisomy of the long arm of chromosome No. 17; the most common aberration was an i(17q) chromosome. Every tumor showed trisomy of the long arm of either chromosome No. 1 or 17. These changes in chromosomes No. 1 and 17 have been observed by others in many different tumors and are not unique to retinoblastoma. In summary, chromosome abnormalities were present in all retinoblastoma tumors studied, but no aberration common to all tumors was found.

Animals

Familial retinoblastoma: segregation of chromosome 13 in four families.

Fluorescent markers on chromosome 13 have been used to study familial retinoblastoma. One family showed concordant segregation of a particular chromosome 13 and retinoblastoma from the affected parent to the affected children. In three other families, segregation was discordant. Meiotic crossing over with recombination is proposed as the explanation.

Adult

Absence of chromosome breakage in patients with retinoblastoma.

Mixed lymphocyte cultures were employed to assess the degree of spontaneous chromosome fragility in patients with retinoblastoma. There was no difference between the patients and their controls. If chromosome instability plays a role in the inherited tumour, more sensitive methods need be employed to elucidate it.

Chromosome Aberrations

Reduced lymphocyte transformation in early cancer of the breast.

The cell mediated immune response has been measured in vitro by lymphocyte transformation in 53 patients with malignant tumours of the breast and an equal number of patients in the same age group operated upon for benign tumours. The response to phytohaemagglutinin (PHA) was reduced in the patients with malignant tumours when the lymphocytes were grown either in the patient's plasma or in autologous plasma. This was observed when the response was measured both by the uptake of radioactive DNA precursor and by autoradiography. Reduced lymphocyte transformation was present even very early in the disease and certainly preoperatively. The reduction appeared to be even more marked in the advanced cases. An interesting finding was that the plasma from cancer patients contained a factor which reduced the PHA transformation of lymphocytes from a healthy donor.

Autoradiography

Acquired trisomy 9.

Explore the source record for details and available documents.

Bone Marrow Diseases