Isozyme patterns of branched-chain amino acid transaminase in human tissues and tumors

The isozymes (enzymes I and III) of branched-chain amino acid transaminase (EC 2.6.1.42) from various human tissues were separated by DEAE-cellulose column chromatography. Their distributions were found to be considerably different from those in rat tissues reported before. In rats, all tissues examined contained enzyme I and in addition enzyme II was found in the liver and enzyme III in the brain, ovary, and placenta. In humans, however, enzyme II was not found in any tissues examined including the liver, and enzyme III was found in many other tissues besides brain, ovary, and placenta. All normal human tissues except the lung, ovary, and brain contain less enzyme III than enzyme I. Various human cancers of the liver, kidney, stomach, pancreas, and uterus showed significantly higher ratios of enzyme III to enzyme I than those of the corresponding normal tissues. Fetal liver and kidney also contained much higher concentrations of enzyme III than adult liver and kidney. These findings suggest that change of the isozyme pattern of this enzyme in cancer is similar in humans and rats, and that cancer tissues tend to express more immature phenotypes than normal tissues. Enzymes I and III of human tissues showed the same substrate specificities for valine, leucine, and isoleucine, and these amino acids competed for the active site of the enzyme. Thus the hereditary diseases, hypervalinemia and hyperisoleucine-leucinemia, may be due to genetic alteration of the enzyme protein, resulting in change of its substrate specificity.

Renal secondary hyperparathyroidism in aged Sprague-Dawley rats

Fourteen aged Sprague-Dawley rats had typical renal secondary hyperparathyroidism. The renal disease was severe glomerulosclerosis with tubular dilation. The parathyroid glands were enlarged and had hyperplasia of chief cells. Bone lesions were generalized osteodystrophia fibrosa and osteosclerosis. All rats had osteodystrophia fibrosa and it was severe in 10 rats. Only four rats had osteosclerosis and it was moderate. Metastatic calcification was seen in various soft tissues in 13 rats.

Growth behavior of ascites tumor cells in three-dimensional agar culture

Growth behavior in vitro of ascites tumor cells was examined for a model study on the invasion in cancer. For this purpose three-dimensional agar culture was used. Seventeen strains of tumor cells were used. These tumor cells grow floating in ascites as single isolated cells (single cell strain) or forming different per cent of cell aggregates (island type strain). Plating efficiencies of tumor cells were variable, depending on the kinds of tumor stain. It was noted that FM3A cells of the cultured cell line showed almost 100% plating efficiency irrespective of the number of cells inoculated. Tumor cells formed 3 types of colony; that is solid type, mushroom-shaped and disk-shaped colony. These three types of colony were observed in all the tumor strains tested, depending on the position in agar layer. The cells of single cell strains showed the tendency to form loose colonies in which cell contact was loose and cells were easy to liberate from the periphery of the colony. The cells of island type strains showed the tendency to form packed colonies in which cell contact was tight. Growth behavior of cells of ascites tumor in agar medium showed good correlation with that in susceptible animals.

Non-obstructive vesicoureteral reflux in adults: value of conservative treatment

Chronic or recurrent non-obstructive urinary tract infection was investigated in 158 adult patients, 39 of whom had vesicoureteral reflux. Conservative, long-term chemotherapy did not eradicate the reflux in these patients. The characteristics of reflux in adults were studied with cystograms, excretory urograms, cystoscopic findings of the ureteral orifices or trigones and the clinical histories of the patients. These data were evaluated and compared to data obtained from adults with chronic or recurrent uncomplicated urinary tract infection and from children with vesicoureteral reflux who were referred to us during the same period. Non-obstructive vesicoureteral reflux in adults may be considered to be congenital in most cases, since the proportion of trigonal anomalies in adults with reflux is equal to that in children and the frequency of abnormalities at the ureteral orifice and trigonal region is significantly more than the frequency noted in control patients with uncomplicated pyelonephritis. Characteristically, excretory urography revealed caliceal scarring in adults with reflux in contrast to children, in whom a normal or dilated pattern of the upper tract was prominent. Recurring renal infection, for which this congenital defect of the ureterovesical valve must be responsible, produces progressive renal damage. Prolonged conservative treatment is of little use and is often destructive in adults with reflux.

Histological observation of the brain of Tay-Sachs disease with seizure and chronic DPH intoxication--report of an autopsy case

The patients was a 3-year-old boy with psychomotor retardation and attacked by seizures since 8 months of age. On funduscopy, the maculla presented a cherry-red spot. Serum hexosaminidase A activities were as low as 8.2 percent. Both parents were carriers. The patient was diagnosed as classical Tay-Sachs disease by neurological examination. Diphenylhydantoin was continuously given for 2 years and 2 months till his death. Autopsy revealed swelling of the cerebrum, atrophy and sclerosis of the cerebellum, hepatomegaly and mild enlargement of the lymph nodes. Histologically, the cerebrum showed ballooned swelling of nerve cells, slight gliosis and demyelination, while cerebellar Purkinje's cells and granular cells were degenerated and disappeared. The cerebellar cortex showed small focal spongy degeneration. By electron microscopy, membranous cytoplasmic bodies were found in the nerve cells. The change of brain observed in this case were interpreted as a combined result of (i) essential change to classical Tay-Sachs disease, (ii) ischemic change due to frequently repeated seizures, (iii) chronic toxicity by long-term anticonvulsant administration.

Isolation of a cell line insensitive to growth-restricting action of dextran sulfate from 3t6 cells

In the medium containing dextran sulfate, 3T6 cells stopped growth at almost monolayer stage and showed decreased saturation density. This action of dextran sulfate is referred to as a growth restriction. About 70% of untreated 3T6 cells formed piled-up colonies whereas the remaining 30% formed monolayer colonies. Fraction of the latter increased with increasing concentration of dextran sulfate in the medium. Cell lines sensitive and insensitive to the growth-restricting action of the compound were cloned from colonical culture of the wild type cells. Sensitive cells showed a slightly less saturation density than the wild type cells in the presence of dextran sulfate. Insensitive cells grown in dextran sulfate medium showed almost the same growth rate and saturation density as the untreated wild type cells grown in the absence of the compound.

The role of the left atrium in the development of pulmonary hypertension -- experiment with dogs --

The experiments were performed on dogs to confirm the hypothesis that the left atrium plays an important role in raising the pulmonary arterial pressure through the autonomic nervous system. In Experiment I, the left auricular resection of dogs resulted in elevated pulmonary arterial pressure. In Experiment 2, 6% Dextran infusion was performed on four groups of dogs: (1) intact dogs (2) dogs with the left auricular resection (3) with the cardiac denervation (4) with both the left auricular resection and the cardiac denervation. The pulmonary arterial resistance increased after the infusion in the dogs with simple left auricular resection, but was relatively unchanged in all others. The result shows that cardiac denervation prevents the increase of the pulmonary arterial resistance due to the left auricular resection. From this we can conclude that the left auricular resection causes an increase in the pulmonary arterial resistance through the autonomic nervous system.

Ultrastructure of the myocardium in acute febrile mucocutaneous lymph node syndrome

A fine structure of the myocardium was examined in the acute febrile mucocutaneous lymph node syndrome, which was recently prevailing in Japan. The right ventricular myocardial cells in ten cases were observed through endomyocardial biopsies. On light microscopy, accumulation of histiocytes was demonstrated in some cases. Electron microscopic examinations revealed myofibrillar changes, increased glycogen contents and other degenerative changes. On the myocardium of a case in which a biopsy was performed during the active phase of the disease, these changes were prominent. However, these changes were also observed for some months to some degree.

Altered growth behavior of virus-transformed cells after treatment with dextran sulfate

Growth behavior in vitro of 3T3 cells and the cells transformed by polyoma or SV40 virus was studied after their treatment with dextran sulfate. The transformed cells treated with dextran sulfated showed decreased saturation density compared with untreated cells, whereas saturation density of 3T3 cells was hardly affected by treatment with dextran sulfate. The ratio of saturation density of untreated SV3T3 cells to that of the treated cells was 64.1% at 5 microng/ml and was 43.4% at 10 microng/ml of dextran sulfate. In Py3T3 cells the ratio was 45.0% at both concentrations of 10 and 20 microng/ml. Plating efficiency was not affected in 3 cell lines tested after treatment with dextran sulfate. The treated cells showed a tendency to form thin and not piled-up colonies in the central area. The treated SV3T3 and Py3T3 cells were flattened in shape compared with the untreated cells. In agar medium the treated SU 3T3 and Py 3T3 cells showed the tendency to stop growing after forming small colonies, whereas the untreated cells kept growing anf formed large colonies. These results suggested that dextran sulfate altered temporarily the growth of the transformed cells to that of untransformed cells.

Altered growth behavior and phenotypic expression of cells of mouse and hamster cell lines after treatment with polyanions

Effect of polyanions on saturation density and production of viscous substance of cells of mouse and hamster cell lines was studied. Cell lines used were 3T6, HA-2 and HA-8 cells. Polyanions were dextran sulfate, (3,6-anhydro-4-o-beta-galactopyranosyl-2-D-galactopyranose-2,4'-bis (potassium/sodium sulfate) (1 leads to 3) polysaccharide (polygeenan) and dextran phosphate. Dextran sulfate reduced the saturation densities of cell lines. Growth of 3T6 cells was not significantly affected by dextran sulfate. Polygeenan and dextran phosphate could not decrease the saturation densities of all the cell lines tested. The production of viscous substance into medium from the treated cells increased after treatment with all polyanions with the exception of dextran phosphate of molecular weight 40,000. It was suggested that specific structure of polyanion might be necessary for the decrease of saturation density of cell lines. Furthermore, it appears that dextran sulfate decreases saturation density of cell line along with change of phenotypic expression of cells.

An analysis of the action of ATP and related compounds on membrane current and tension components in bullfrog atrial muscle

The effect of adenosine compounds (ATP, ADP, AMP and adenosine) on membrane potential, current and contractile tension on the bullfrog atrium were studied under voltage clamped and unclamped conditions. The compounds produced immediate positive and late negative inotropic effects in unclamped conditions. The positive inotropic effect and the potency of drugs appeared less marked in the order of ATP, ADP, AMP, and adenosine. Under voltage clamped conditions, only the energy rich compounds, ATP and ADP, produced an enhancement of calcium inward current (Ica) and Ica-dependent phasic tension, while AMP and adenosine elicited a negative inotropic effect. The delayed outward current was initially depressed but later augmented epecially in case of ATP and ADP where Ica was enhanced. All adenosine compounds, however, inhibited the Ica-independent tonic tension. This effect, appearing nonspecific, was ascribable to the action of common structure of these compounds, purine-riboside moiety.

A basic study of the Hanssen technique for evaluation of single nephron glomerular filtration rate

The purpose of this study was mainly to examine some basic problems of the Hanssen technique for the evaluation of single nephron glomerular filtration rate (SNGFR). Firstly, experiments were performed using Wistar rats to determine the amount of C14-ferrocyanide necessary to give sufficient C14 radioactivity in dissected nephrons. Using 200 muCi of C14-ferrocyanide, the samples of dissected nephrons provided only twice as much as background. Hence, we chose the amount of 600 to 700 muCi of C14-ferrocyanide for each rat in the later experiments, which yielded the radioactivity 5 to 6 times as much as background. Secondly, the homogeneity of intrarenal C14-ferrocyanide distribution was tested. Five superficial (SUP) and juxtamedullary (JM) proximal tubules four different regions were dissected and the radioactivity of those nephrons was counted. The distribution of C14-ferrocyanide in each piece was representative of the overal distribution. The summary of morphologic and clearance studies were as follows. The mean lengths of proximal tubules of 40 SUP nephrons, 5.3 +/- 0.2 mm, and 39 JM nephrons, 6.3 +/- 0.1 mm, were significantly different (P less than 0.01). The mean glomerular diameter of the JM nephrons, 110 +/- 2.7 mu, was significantly greater than that of the SUP nephrons, 95 +/- 3.1 mu (P less than 0.01). The mean SNGFR of 129 SUP nephrons, 23.4 +/- 4.2 nl/min/100g Body Weight (BW), and that of 130 JM nephrons, 34.5 +/- 5.1 nl/min/100g BW, were significantly different (P less than 0.01). The ratio of superficial/juxtamedullary nephron glomerular filtration rate (S/JM Ratio) was 0.85 +/- 0.02. We conclude that C14-ferrocyanide is regularly distributed to the kidney and that it is necessary to infuse sufficient amount of C14-ferrocyanide in this technique.

Further studies on the possible compartmentation of the precursor pool of cholesterol for the biosynthesis of cholic acid in the rat

In vivo and in vitro experiments with rats were carried out to investie precursor for the biosynthesis of cholic acid. When rats with a bile-fistula were given a mixture of [2-14C]mevalonate and [1,2-3H]cholesterol intravenously, the 14C:3H ratio in cholic acid in both whole homogenate and cytosol prepared from their lives was higher than that in free cholesterol in any subcellular fraction of the livers. When [2-14C] mevalonate was administered intravenously to bile-fistula rats, the specific radioactivity of free cholesterol in the hepatic microsomal fraction exceeded that in any other fraction, and the specific radioactivity of biliary cholic acid was remarkably high, exceeding that of microsomal free cholesterol. In similar experiments with [4-14C] cholesterol, the specific radioactivity of free cholesterol in the hepatic microsomal fraction exceeded that in any other subcellular fraction and the specific radioactivity of biliary cholic acid was lower than that of free cholesterol in any hepatic subcellular fraction. Tissue suspensions of rat livers in Krebs-Ringer bicarbonate (pH 7.4)-5.5 mM glucose were incubated with [2-14C]mevalonate in O2-CO2 (95:5, v/v) at 37 degrees. The specific radioactivity of free cholesterol in the microsomal fraction prepared from the incubated tissue exceeded the specific radioactivities of free cholesterol in the other subcellular fractions. The estimated specific radioactivity of taurocholate formed during the incubation was far higher than that of microsomal free cholesterol. These data indicate that hepatic microsomal free cholesterol which was newly synthesized in situ was preferentially incorporated into cholic acid.