Structure, assembly, conformation, and immunological properties of the two subunit classes of ferritin

The two subunit types of human liver ferritin were purified to homogeneity. Both subunits reassembled in a well-defined manner and formed spherical particles that resembled natural apoferritin in electron micrographs. Affinity chromatography methods were employed to obtain preparations of antibodies that interacted exclusively either with the H or with the L polypeptides, demonstrating that distinct immunological properties may be ascribed to each subunit of ferritin. The amino acid compositions of the subunits were similar, but the larger H subunit had fewer leucine, phenylalanine, and arginine residues. It is therefore improbable that H subunits undergo proteolytic processing and are precursors for L subunits. Circular dichroism data indicated that homopolymers assembled from L-type subunits had substantially more ordered secondary structures and greater alpha-helical contents than their H counterparts. Small differences in the environment of tryptophan residues were evident from fluorescence spectra of each homopolymer. In isoelectric focusing experiments reassembled H or L homopolymers migrated as families of proteins within discrete pI ranges which are probably representative of subpopulations of each subunit type. The H homopolymer focused at lower pI's than the L component. These data substantiate the contention that both subunits are authentic polypeptide moieties of ferritin with some common structural features, but the results also underscore prominent dissimilarities in their properties.

Computed tomography in von Recklinghausen's disease

Though we knew it would be difficult to predict whether a child having von Recklinghausen's disease would develop a central nervous system lesion in the future, we tried to find a clue to this question in our study, by comparing computed tomography (CT) findings of 18 children with those of 21 adults. 55% of the children and 85% of the adults showed abnormal findings on CT. The most common finding was mild ventricular dilatation without periventricular hypodensity. Some of them showed ventricular stasis without block on radioisotope cisternography.

Pancreatic tumors induced by a single intraperitoneal injection of azaserine in partial pancreatectomized rats

Pancreatic tumorigenesis of azaserine by a single intraperitoneal (i.p.) injection after partial pancreatectomy in male Wistar rats was studied. Pancreatic lesions developed in all rats 52 weeks after the administration of azaserine at doses of 50 mg (Group 1) or 100 mg/kg body wt (Group 2). Histologically, there were hyperplastic nodules in 4 of 12 rats and 4 of 7 rats, in Groups 1 and 2, respectively, adenomas 100% in both groups, and adenocarcinomas 2 of 7 rats of Group 2. It appears that pancreatic regeneration induced by partial pancreatectomy enhances the azaserine tumorigenesis.

Carcinogenic effect of N-bis-(2-hydroxypropyl)nitrosamine in newborn rats

The carcinogenic effect of N-bis(2-hydroxypropyl)nitrosamine (BHP) was studied in newborn Wistar rats. Tumors were induced in the lung (adenoma), pancreas (adenoma), kidney (nephroblastoma), and ovary (benign granulosa cell tumor) at 24 weeks after the treatment and in the lung (adenoma and adenocarcinoma), liver (hemangioma, hemangioendothelioma, and hepatocellular carcinoma), pancreas (adenoma), kidney (renal cell carcinoma and nephroblastoma), thyroid (adenocarcinoma) and ovary (benign and malignant granulosa cell tumors) at 52 weeks. The highest incidence of tumor was seen in the liver of rats applied BHP within 24 hours after birth. These results indicate that newborn Wistar rats are more susceptible to BHP than are adult rats.

Developmental changes in normal cranial measurements by computed tomography

Computed tomography (CT) scans were examined for 89 selected patients in an attempt to establish normal values at various ages for longitudinal and transverse diameters of the brain, the greatest distance between the right and left sides of the anterior horn of the lateral ventricle, the width of the lateral ventricles in the region of the caudate nuclei, and the greatest width of the third ventricle. The patients' ages ranged from less than one year to over 40 years. These measurements and their ratios to one another are reported. The cerebral longitudinal fissure, Sylvian fissure and subarachnoid space were evident to some degree below the age of two years, especially below the age of one year, and again above the age of 40 years. The cortical sulcus was occasionally found to have a width of less than 1.9mm below the age of one year and above the age of 40 years.

Computed tomography in tuberous sclerosis--with special reference to relation between clinical manifestations and CT findings

Concerning the clinical signs and symptoms, we noticed skin white macula in 87%, adenoma sebaceum in 53%, mental retardation in 75%, retinal phacoma in 54% and seizure in 92%. Numbers of nodules ranged from zero to 11, and showed no correlation with aging. Half of the cases showed slight ventricular dilatation, one quarter showed moderate dilatation and the remainder were normal. There was no definite correspondence between size of the ventricle and number of nodules. There were relatively many cases with normal mental state in the group with normal ventricles. In adult cases a large ventricle does not always mean poor prognosis in mental state. Almost all of the cases with cortical atrophy had mental retardation. In the group with moderate dilatation infantile spasms were the most frequent type of seizure. On the contrary, grand mal was most frequent in the normal group. As for the position of nodules there was no difference between the normal and dilated groups. Nodules were predominantly seen in the lateral aspect of the body, trigone of the lateral ventricle and adjacent to the foramen of Monro. Asymmetrical lateral ventricles were noticed in 18%. Incidence of laterality increased as dilatation proceeded. It was larger on the left side in 9 out of 11 cases. We have no reasonable explanation of this tendency. There was one case with a tumor which was verified by enhanced CT. There were five cases with brain anomalies.

HLA--Bw54 (Bw22-J, J-1) antigen in juvenile onset diabetes mellitus in Japan

HLA--B8 and/or Bw15, associated with juvenile onset insulin-dependent diabetes mellitus (JDM) in Caucasians, have a very low frequency in the Japanese population. Thus, we were interested in investigating the association between JDM and HLA antigen in a Japanese population. Eighty-nine patients with JDM and 128 unrelated random controls were HLA-typed by the microlymphocytotoxicity test. The data revealed a significant, positive association between this type of diabetes mellitus and HLA--Bw54 (Bw22-J, J-1) antigen (Japanese-specific split antigen of HLA--Bw22).

Benign desoxycorticosterone-producing adrenal tumor

A woman with a benign tumor of the left adrenal cortex had a six-year history of hypertension. Serum potassium level and plasma renin activity were low. Plasma aldosterone and cortisol levels were low normal, and plasma desoxycorticosterone (DOC) level was extremely high. Iodine 131-labeled cholesterol accumulated in the tumor in the left upper quadrant of the abdomen. At laparotomy, a benign adrenal tumor was excised; thereafter, the blood pressure and plasma DOC levels returned to normal. We believe that this is the first case of a benign DOC-producing adrenal tumor.