Systemic amyloid deposition in old age and dementia of Alzheimer type: the relationship of brain amyloid to other amyloid

We investigated amyloid deposition in the brain and other organs in 105 consecutive autopsy cases, aged 59 to 101 years. They consisted of two groups; 15 patients with dementia of Alzheimer type (DAT) and 90 patients without DAT. Amyloid deposition was found in 93% of all cases. The incidence of amyloid deposition increased with age. The number of organs affected with amyloid deposition in each case also increased with age. The incidence of amyloid deposition in each organ was as follows; 88% in pituitary gland, 66% in brain [amyloid of senile plaque (SP) (61%) and/or cerebral amyloid angiopathy (CAA) (56%)], 33% in pancreas, 3% in heart, and less in others. In immunohistochemical studies using the antisera to the various kinds of amyloid or related proteins, amyloid beta protein was demonstrated in brain amyloids including SP and CAA, but not in others. Cardiac amyloid was positive for prealbumin. Pituitary amyloid and CAA were positive for amyloid P-component. The incidence of brain amyloids in DAT were significantly higher than that in non-DAT. There was no significant difference in the incidence of pituitary and pancreatic amyloid between DAT and non-DAT. In the non-DAT patients, there were significant positive correlations in amyloid deposition between the brain and pituitary gland and between the brain and pancreas. Acceleration of amyloid deposition would be a process confined to the brain in the patients with DAT. The pathogenesis of the accelerated deposition of brain amyloids is discussed from the point of view of amyloidosis.

Growth kinetics of fibroblasts from a patient with Ehlers-Danlos syndrome

A 6-year-old girl with Ehlers-Danlos syndrome (type I) who shows hyperelastic skin, hypermobile joints and delayed wound healing is reported. The growth kinetics of fibroblasts derived from her skin was examined using 3H-thymidine autoradiography. Our study showed that these fibroblasts had poor proliferative activity, compared with normal age-matched fibroblasts. Thus, we could suggest that the pathogenesis of Ehlers-Danlos syndrome was partially attributed to the lack of proliferative activity of the fibroblasts.

Exchange of dominant lymphoid cell clones in a patient with adult T-cell leukemia/lymphoma

We performed a genotypic study on lymphoid cells from a patient with adult T-cell leukemia (ATL). Clonal proliferation of human lymphotropic virus type-1(HTLV-1)-infected helper T-cells was detected in the primary skin tumors, while no clonality of the virus-infected lymphocytes was observed in the peripheral blood. Following intensive chemotherapy, however, we detected the presence of two genotypically different HTLV-1-infected lymphocyte clones in different samples taken from the peripheral blood. These data demonstrated the exchange of the dominant neoplastic clone in the clinical course of ATL, suggesting the possibility that a certain clone among many repertoires of HTLV-1-infected T-cells has a capability of leukemogenesis, instead of the primary tumour cells.