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Biomedical subjects

J Sato

Publications and source records attributed to J Sato.

At least 397 records · Page 22Linked to original sources
PubMed1986

Microheterogeneity of Kasahara isozyme.

The microheterogeneity of Kasahara isozyme was investigated by affinity electrophoresis with Con A as the affinity ligand in combination with polyacrylamide gradient gel electrophoresis. On two-dimensional Con A-containing agarose gel electrophoresis, the Kasahara isozyme was separated into three molecular species. Kasahara isozyme electrophoresed as two distinct bands with enzyme activity on polyacrylamide gradient gel, but liver, intestinal or placental alkaline phosphatase showed only one distinct spot or band on both electrophoreses. One of the three molecular species of Kasahara isozyme separated by Con A-containing agarose gel electrophoresis was extracted from the gel and applied to the polyacrylamide gradient gel electrophoresis again, resulting in the same electrophoretic pattern as that of the original Kasahara isozyme. These findings indicated that the Kasahara isozyme consists of at least four molecular species. The same analysis was conducted with alkaline phosphatase of the HuH-6 cl-5 cell line, which has been reported to release an alkaline phosphatase closely resembling the Kasahara isozyme, and the results were compared with those obtained with the Kasahara isozyme.

Alkaline Phosphatase↗
PubMed1986

Promotion of 3'-methyl-4-dimethylaminoazobenzene-initiated adult rat liver cells to malignant state by phenobarbital in culture.

After treatment with 1.5 mM phenobarbital (PB) for about 2 months, non-tumorigenic rat liver epithelial-type cell lines (6F-7 and 6G-5), which were initiated by 3'-methyl-4-dimethyl-aminoazobenzene (3'-Me-DAB) in primary culture, showed an increase in plating efficiency, growth in soft agar and production of tumors in syngeneic animals. However, the PB-untreated control cells exhibited neither growth in soft agar nor production of tumors. Gamma-glutamyltranspeptidase (GGT)-positive (6F-7-cl-7) and negative (6F-7-cl-8) colonial clones, which were derived from 6F-7 cells, were also treated with 1.5 mM PB for about 2 months. The growth of GGT-positive 6F-7-cl-7 cells was not suppressed but rather stimulated by PB at 1.5 mM, whereas that of GGT-negative 6F-7-cl-8 cells was severely inhibited. Furthermore, the PB-treated 6F-7-cl-7 cells produced tumors in syngeneic animals, but the PB-treated 6F-7-cl-8 cells produced no tumors. The spontaneous cell line 6A-6, which was derived from the 3'-Me-DAB-untreated primary liver cell culture and was GGT-negative, did not exhibit tumorigenicity after treatment with 1.5 mM PB for the same period of time as described above. In conclusion, PB treatment efficiently and rapidly promoted the 3'-Me-DAB-initiated cells to a malignant state.

Animals↗
PubMed1986

Ultrastructure of concentric laminations in primary human brain tumors.

Ultrastructural concentric laminations have previously been thought to be specific to oligodendroglioma. However, these structures were also recognized in fibrillary astrocytomas, a mixed glioma and a glioblastoma. These laminations continued or closely related to attenuated processes or cytoplasm of astrocytic tumor cells. In addition, some lamellae contained glial filaments. It is considered that the concentric laminations are derived from attenuated astrocytic processes and have no relationship with myelin.

Adolescent↗
PubMed1986

Perfusion technique of suckling rat liver, and comparison of cytologic and biochemical properties between hepatocytes isolated from suckling and adult rats.

Collagenase-liver-perfusion technique, currently used with adult rat liver, was applied to isolation of hepatocytes from suckling rat liver. The total hepatocyte numbers isolated from suckling rats by collagenase-liver-perfusion technique were 9-fold higher than those by non-perfusion technique. The yield and viability of isolated hepatocytes from suckling rats were 18.1 X 10(7) cells per gram liver and 95%, respectively. The cell yield per gram liver and viability from suckling rats were 185% and 112% of those from adult ones, respectively. In comparison with adult rat hepatocytes, suckling rat hepatocytes were smaller and more homogeneous. The percentage (3.1%) of binucleate cells in the hepatocytes isolated from suckling rats was about one tenth of that (30.7%) in the hepatocytes isolated from adult rats. The isolated suckling rat hepatocytes had higher tyrosine aminotransferase (TAT) and glucose-6-phosphate (G6Pase) activities than adult ones. Suckling and adult rat hepatocytes were transferred to primary culture to compare their cell number kinetics and functional longevities. The functional longevities of those hepatocytes were assessed by their capacity to secrete albumin and alpha-fetoprotein (AFP) into the culture medium and to express TAT and G6Pase activities up to day 6 of primary culture.

Albumins↗
PubMed1986

The effect of conditioned medium on fetal human liver cells in primary culture.

A medium conditioned by rat embryo cultures (RCM) promoted the adhesion of liver cells from human fetuses to plastic dish. Colonies were also formed in primary cultures of the same cells in the presence of RCM. The majority of the colonies formed were composed of large polygonal cells with a few colonies composed of both clear epithelial-like cells and fibroblast-like cells. RCM was superior to the rat embryo feeder layer for promotion of colony formation of cells. A number of colonies were formed from fetal human livers when a conditioned medium from human hepatoma cells (HCM) was used, but most of the colonies formed were composed of fibroblast-like cells. The cells derived from the polygonal cell colonies, which were formed in the presence of RCM, have been passaged four times and they are still growing with albumin-producing capacity. The effect of RCM was reduced by various physico-chemical treatments.

Animals↗
PubMed1986

Primary cultures of human livers and their albumin-producing capacity.

Primary cultures of surgically obtained noncancerous portions of human liver tissues were made. Liver tissues were poorly dissociated with collagenase, but well dissociated with dispase. The yield and viability of cells were improved somewhat when dissociated with collagenase followed by dispase. The mean cell yield was 1.1 X 10(6) cells/g liver. The epithelial-like morphology of the dissociated liver cells was maintained for about one week, but thereafter degenerative alteration of cells was observed. In liver explant culture, an active outgrowth of cells was observed for more than one month. Albumin production in culture fluids from dissociated livers was detectable for about 2 weeks, but later became undetectable, while that from explant culture was detectable for at least one month. These data demonstrate that adult human hepatocytes can be isolated from noncancerous portions of livers with relatively high yield, and that albumin production of the dissociated cells is detectable for several days.

Adult↗
PubMed1986

Comparative study of proliferation of suckling and adult rat hepatocytes in primary culture in response to growth-stimulating factors.

The replicative responses of suckling and adult rat hepatocytes in primary culture to growth-stimulating factors were compared. By addition of L-proline alone, the [3H]-thymidine labeling of suckling rat hepatocytes was dramatically enhanced, but that of adult ones was not. Epidermal growth factor (EGF), insulin, triiodothyronine (T3) and glucagon also enhanced the labeling of suckling rat hepatocytes regardless of the presence or the absence of L-proline. On the other hand, in the absence of L-proline, only EGF enhanced the labeling of adult rat hepatocytes, and, in the presence of L-proline, insulin as well as EGF enhanced the labeling. In the presence of growth factors and L-proline, the number of suckling rat hepatocytes increased up to about 143%, whereas that of adult rat hepatocytes hardly increased. Thus, a remarkable difference in replicative responses to growth factors and L-proline was observed between suckling and adult rat hepatocytes in primary culture.

Aging↗
PubMed1986

An attempt to eliminate fibroblast-like cells from primary cultures of fetal human livers.

The elimination of fibroblast-like cells from primary cultures of fetal human livers was studied. A fibroblast-like cell line (HuF), which was obtained by subculturing fetal human liver cells 4 or more times, was briefly treated with hydrocortisone (HC) or putrescine (PUT). The growth of HuF cells was inhibited by HC at a concentration of 10(-2) M and by PUT at a concentration higher than 10(-3) M. Long-term treatment of HuF cells with 10(-3) M HC inhibited the growth of the cells. Primary cultures of fetal human livers were made in medium containing HC or PUT, and morphological and functional examinations were made. The cultures were predominantly composed of epithelial-like cells, with few fibroblast-like cells, when the HC concentration was 10(-5)M to 10(-3) M. A high amount of albumin was secreted at these concentrations of HC. On the other hand, at 10(-3) M PUT, many epithelial-like cells were seen, but albumin was undetectable. The present results indicate that albumin-producing epithelial-like cells can be selectively maintained in medium containing HC, in primary cultures of fetal human livers.

Albumins↗
PubMed1986

New equations to calculate temperature correction factors for PO2 in human blood.

Effects of hemoglobin concentration (Hb), pH, and body temperature (T) on the relationships between delta log PO2/delta T and PO2 were studied by means of a mathematical model using a Newton-Raphson iteration method. The functions between delta log PO2/delta T and PO2 were affected by the above three factors. New equations considering the effects of Hb, pH, and T were proposed by modifying the equation reported by Severinghaus: delta log PO2/delta T = (L +(U-L)/(A(vPO237)B + 1))(10(-2) where U = 3.15-0.45(7.4-pH37) L = 0.68-0.09(7.4-pH37) A = 5.86(exp10(0.074(T)-0.294(7.4-pH37)-11))((Hb)0.913) B = 6.33(exp10(-0.0051(T)))((Hb)-0.113) + 0.24(7.4-pH37) and vPO237 is virtual PO237 which may exist when PO237 is corrected to standard conditions (pH = 7.4, BE = 0) by the following equations: vPO237 = PO237(exp10(fB(7.4-pH37)-0.0013(BE))) fB = (PO237/26.6)0.08-1.52 where fB is the Bohr factor. The above equations provided values of delta log PO2/delta T which fit closely to those obtained by the complex iteration method with maximum differences of less than 1.3 X 10(-3) at T = 27, indicating that maximum % errors for PO2 at T (PO2T) are less than 3.0% at T = 27 and that our equations can be applied over a wide range of Hb, pH37 and T.

Bicarbonates↗
PubMed1986

Actinopyrones A, B and C, new physiologically active substances. I. Producing organism, fermentation, isolation and biological properties.

A strain of Streptomyces was found to produce new physiologically active substances. The active compounds were purified and separated into three substances named actinopyrones A, B and C. Actinopyrones exhibited coronary vasodilating activities in anesthetized dogs and weakly antimicrobial activities against some Gram-positive bacteria and dermatophytes.

Animals↗
PubMed1986

[Intraoperative ultrasonography through a burr hole: clinical trial of ultrasound-guided stereotactic surgery].

Intraoperative ultrasound diagnosis through a burr-hole was performed in 59 cases using electronic sector-scanning transducers. The burr-hole was conically enlarged and the gap between the transducer tip and the dura mater was filled either with saline or sterile echojelly. The pathology was successfully imaged in 33 cases (56%), or 20 out of 28 cases (71%) using a 5 MHz transducer. Compared to transdural ultrasonography, the quality of image through a burr-hole was found less satisfactory. Six cases of biopsy and/or aspiration were successfully performed under ultrasonic guidance through a burr-hole. Two burr-holes were necessary in these stereotactic operations. A needle-guide apparatus and the guideline superimposed on the monitor CRT screen were advantageously utilized. In biopsy, both the tumor and the biopsy needle were visible on the same monitor CRT screen, and accurate biopsy was possible. In aspiration, the tip of the needle could always be kept inside the cyst or abscess cavity. Bleeding during these manipulations was easily detected on the real-time monitoring CRT screen, and if necessary, it could be immediately controlled. Our results suggest that the intraoperative ultrasonography through a burr-hole will make these operations safer and more accurate.

Adolescent↗
PubMed1986

Malignant transformation of rat liver cells by N-benzoyloxy-3'-methyl-4-methylaminoazobenzene and its related compound.

N-Benzoyloxy-3'-methyl-4-methylaminoazobenzene-(N-benzoyloxy-3'-Me-MAB) was highly toxic to rat liver epithelial cells (Ac2F) and induced many more chromosome aberrations and unscheduled DNA synthesis than did 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB). N-Benzoyloxy-3'-Me-MAB and its related compound, N-acetoxy-4-methylaminoazobenzene, efficiently induced malignant transformation of the cells, but 3'-Me-DAB was not so effective. The cells transformed by N-acyloxy-4-methylaminoazobenzene (N-acyloxy-MAB) derivatives showed significant increases in plating efficiency in liquid medium and in the size of aggregates in rotation culture. Such increases were not seen in the 3'-Me-DAB-transformed cells. The results indicate that the N-acyloxy form of the 4-dimethylaminobenzene derivatives seems very likely to be the ultimate metabolite.

Animals↗
PubMed1986

[Study of metabolism in critically ill patients by indirect calorimetry].

Indirect calorimetry was performed in 48 postsurgical critically ill patients including those with multiple organ failure. The patients were divided into two groups, organ failure group (OF group) and postsurgical control group (C group), according to the presence of postsurgical organ failure and severe infection. The following results were obtained. The ratio of energy expenditure to basal energy expenditure, reflecting a degree of hypermetabolism, was 1.44 +/- 0.38 in OF group and 1.26 +/- 0.23 in C group respectively. The change in respiratory quotient by caloric intake was greater in OF group than in C group, indicating that it is more important to maintain an adequate intake for the prevention of increased respiratory work and excess lipogenesis in OF group. When nitrogen intake as amino acids was sufficient (0.1-0.2 g/kg/day), nitrogen balance could be maintained around 0 by a caloric intake being equal to measured energy expenditure. A positive correlation was observed between arterial ketone body ratio reflecting energy charge in hepatocytes and respiratory quotient, indicating that in patients with impaired mitochondrial function in hepatocytes as shown by a decrease in ketone body ratio, glucose cannot be utilized effectively. These results let us conclude that calorimetry is indispensable in the management of critically ill patients and that adequate energy intake should be cautiously determined according to the calorimetry.

Calorimetry↗