Search PubMed⌕ Search

Biomedical subjects

J Sato

Publications and source records attributed to J Sato.

At least 361 records · Page 20Linked to original sources
PubMed1988

Mixed oligodendroglioma and astrocytoma: fine structural and immunohistochemical studies of four cases.

Four mixed oligodendrogliomas and astrocytomas were investigated by electron microscopy and immunohistochemistry (GFAP, NSE and MBP). GFAP-positive oligodendroglioma cells and their transitional cells to GFAP-negative oligodendroglioma cells were present, suggesting successive morphological changes of astrocytic tumor cells. NSE-positive cells, suggestive of residual neurons, also exhibited round nuclei and perinuclear halos. On electron microscopy, oligodendroglioma cells that showed glial filaments, vascular end-feet and zonulae adherentes were occasionally present. The tumor cells with or without astrocytic characteristics showed common features of cytoplasmic organelles. These findings suggest that most oligodendroglioma cells in mixed gliomas are of an astrocytic nature and that characteristic microscopic features of oligodendroglioma are of a common cellular form that can be taken by various types of cells under certain circumstances.

Astrocytoma↗
PubMed1988

Effects of various substrates on human hepatoblastoma and hepatoma cell culture.

The effects on human hepatoblastoma (HuH-6) and hepatoma (HuH-7) cell lines of collagen type I (CI), type IV (CIV), fibronectin (FN) and laminin (LAM) were investigated. CI and CIV promoted almost equally the attachment of both cell lines more strikingly than did FN or LAM. CI and CIV were also superior to FN or LAM in supporting the growth of HuH-6. These substrates, however, had no appreciable effect on the growth of HuH-7. The amount of alpha-fetoprotein (AFP) and albumin secreted in HuH-6 was found to be higher on FN- and LAM- coated substrates than on the other matrix material- coated ones. HuH-7 exhibited increased levels of AFP on LAM- coated substrates 4 days after plating. These results indicate that the ability of extracellular matrix materials to enhance attachment and/or growth is different from that to enhance AFP and albumin production in HuH-6 and probably in HuH-7.

Carcinoma, Hepatocellular↗
PubMed1988

Comparison between fluctuating PEEP and conventional PEEP in dogs with lung injury induced by blood aspiration.

It has been documented that in some patients with acute hypoxic respiratory failure the application of positive end-expiratory pressure (PEEP) may produce no improvement or even a deterioration of pulmonary oxygenation due to an increase in ventilation-perfusion mismatching. Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with localized lung injury induced by the aspiration of non-heparinized blood (2 ml.kg body weight-1), F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at frequencies of 10 min, and conventional PEEP with 3 different fixed EEPs, 0.5, 1.0 and 1.5 kPa (C-PEEP0.5, C-PEEP1.0 and C-PEEP1.5) were each applied for 60 min. F-PEEP produced a periodical change in PaO2 and hemodynamic variables including cardiac output, and in comparison with C-PEEP0.5, C-PEEP1.0 and C-PEEP1.5, a significantly greater improvement of A-aDO2 and dynamic compliance with relatively large cardiac output in the low EEP phase. These results suggest that F-PEEP is a useful mode of artificial ventilation for treating some kinds of acute hypoxic respiratory failure due to increased ventilation-perfusion mismatching.

Animals↗
PubMed1988

Fluctuating PEEP (F-PEEP) versus conventional PEEP in dogs with asymmetrical lung injury.

Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.

Animals↗
PubMed1988

Fluctuating PEEP versus conventional PEEP in diffuse and unilateral lung injury induced by oleic acid.

Effects of fluctuating positive end-expiratory pressure (F-PEEP), in which end-expiratory pressure (EEP) was periodically changed from 0.5 to 1.5 kPa with a periodic time of 6 min, and conventional PEEP (C-PEEP) with a fixed EEP of 1.0 kPa, were comparatively studied in diffuse (Group I) and unilaterally dominant lung injury (Group II). Although F-PEEP produced cyclic alterations of PaO2 in both groups, PaO2 changed in proportion to EEP in Group I and in reciprocal proportion to EEP in Group II. There was no significant difference between PaO2 and QS/QT during F-PEEP and those during C-PEEP in Group I, whereas in Group II, F-PEEP produced a significantly greater improvement of pulmonary oxygenation at the low EEP phase than C-PEEP. In both groups, the degree of hemodynamic depression was proportional to EEP. These results suggest that F-PEEP should be indicated for acute hypoxic respiratory failure with uneven distribution of lung injury.

Animals↗
PubMed1988

A method for rapid preparation of single-cell suspensions from rat hepatocyte primary cultures on collagen substratum and the mechanism of cell dissociation.

A method has been developed for the rapid preparation of single-cell suspensions from rat hepatocyte primary cultures on collagen substratum. Hepatocytes were adequately dissociated into single cells when the cultures were first treated with a combination of trypsin and ethylenediaminetetraacetic acid (EDTA) and then with collagenase. However, when the order was reversed, hepatocytes were inadequately dispersed. The possible mechanism of cell dissociation is discussed on the basis of the experimental data obtained.

Animals↗
PubMed1988

Decreased albumin secretion in serum-free primary cultures of adult rat hepatocytes during proliferation induced by epidermal growth factor and insulin.

Upon addition of epidermal growth factor (EGF, 0.1 microgram/ml) and insulin (0.1 microM), adult rat hepatocytes proliferated and increased 120-134% in number in serum-free primary culture. However, in the absence of the growth factors, hepatocytes decreased in number with time. The average albumin secretion per cell was much lower in the proliferating cultures than in the non-proliferating cultures. The results suggest that albumin production in hepatocytes decreases during cell proliferation.

Albumins↗
PubMed1988

Observations on electrophysiologically characterized receptive fields of thin testicular afferent axons: a preliminary note on the analysis of fine structural specializations of polymodal receptors.

The sparse distribution of thin, principally unmyelinated sensory axons confined largely to the planar tunica vasculosa of the testis provides a suitable model for examining the fine structure of electrophysiologically characterized nerve fiber terminals. The marked sites of polymodal receptors of canine testis using the in vitro preparation devised by Kumazawa et al. (1987) were examined in serial sections traced to the terminal with the electron microscope, revealing the first micrographs of a characterized polymodal receptor ending. The inferred role of these terminals in nociception, their organelle content, and the problems encountered in interpreting our initial findings are considered in the context of the variety of morphological patterns and functional roles of thin sensory axons.

Animals↗
PubMed1988

[Effects of various factors on the growth and function of a human hepatoblastoma cell line, HuH-6--an approach for serum-free cell culture].

The effects on a human hepatoblastoma cell line (HuH-6) of serum and Ca2+ were investigated. A higher concentration of serum reduced the production of alpha-fetoprotein, whereas Ca2+ enhanced that of both albumin and alpha-fetoprotein. In view of these facts, a serum-free medium using RPMI-1640 supplemented with lactalbumin hydrolysate, epidermal growth factor, hydrocortisone, insulin, chrelatoxine, glucagone and selenium was then developed. Collagen type IV was superior to collagen type I, laminin, fibronectin and plastic in supporting the growth of HuH-6 in the serum-free medium. Higher amounts of both albumin and alpha-fetoprotein were secreted in HuH-6 cultured in serum-free medium than in serum-supplemented medium.

Blood↗
PubMed1988

[Establishment and characterization of a human cholangiocellular carcinoma cell line].

A cell line, HuH-28 was established in vitro from a patient with cholangiocellular carcinoma (CCC). This cell line has been in continuous culture over 10 month period with slow growth potential. HuH-28 was composed of spindle-shaped cells as major population besides a small percentage of polygonal-shaped cells. Chromosome number of the cells were distributed near the hypotriploid region on the 3rd passage. HuH-28 cells were not transplantable into nude mice, but secreted some tumor markers including alkaline phosphatase (ALP), gamma glutamyltranspeptidase (GGT), beta 2-microglobulin (BMG), ferritin, elastase-1 and tissue polypeptide antigen (TPA). This HuH-28 cell line will represent a good model for the investigation of carcinogenesis, histogenesis+ and diagnosis of CCC.

Adenoma, Bile Duct↗
PubMed1988

[Culture methods of human liver cells].

Attempts to isolate and cultivate human liver cells have been described. Many viable liver cells have been obtained when dissociated with collagenase followed by dispase. The morphology and differentiated functions have been maintained for more than 3 weeks when human fetal liver cells were cultured not only in medium containing 10(-3) M hydrocortisone, but also on collagen gel substrates with 5 x 10(-7) M hydrocortisone. The colony-forming capacity of primary cultured fetal human livers has also been described in the presence of conditioned medium.

Cell Differentiation↗
PubMed1988

[Attempted marrow rescue with cryopreserved circulating stem cells following high-dose chemotherapy].

Circulating hematopoietic stem cells were collected by three consecutive leukaphereses during post-chemotherapy expansion of the stem cell pool in a 3-year-old boy with advanced and therapy-resistant neuroblastoma. The cells were fractionated by discontinuous Percoll gradient centrifugation, frozen in a programmed freezer and then stored in liquid nitrogen. Following high-dose chemotherapy, the cells were thawed rapidly and re-infused into the patient. Early evidence of marrow recovery was first noted at day 13 and the times required to achieve a granulocyte count of greater than 0.5 x 10(9)/L and a platelet count of greater than 50 x 10(9)/L were 21 days and 30 days, respectively. This new marrow-rescue operation may have potential in cancer therapy as an alternative to bone marrow transplantation and further clinical investigation is warranted.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

[A case of primary carcinoid tumor of the testis].

A case of a primary carcinoid tumor of the testis which occurred in a 57-year-old man is reported. The patient was treated by orchiectomy, and no clinical features of a carcinoid syndrome had been noted. The tumor measured 4.0 X 3.2 X 2.0 cm in size and was yellowish in color. Histochemically, the tumor cells were composed in part of argentaffin and in part of argyrophil. Immunohistochemically, the argentaffin tumor cells were positive for neuron-specific-enolase. No tumor cells were positive, however, for neurofilaments, vimentin, keratin, desmin, GFAP, S-100 protein, ACTH, and somatostatin. Electronmicroscopy revealed numerous neurosecretory granules. Tumorous tissue presented a histomorphology of a pure carcinoid tumor composed of parts of argentaffin and argyrophil.

Carcinoid Tumor↗
PubMed1987

Effects of prostaglandins and other putative chemical intermediaries on the activity of canine testicular polymodal receptors studied in vitro.

An in vitro testis-superior spermatic nerve preparation was used to evaluate the effects of chemical agents applied in the bathing solution. Both directly evoked discharges and responses to algesic solutions [bradykinin (BK) 9 X 10(-8) M, hypertonic saline 616 mM and high K+ solution 60 mM] of polymodal receptors were studied. Prostaglandin (PG)-E2 (1.4 X 10(-6)-1.4 X 10(-5) M) and serotonin (5-HT) (1.1 X 10(-6) to 1.4 X 10(-4) M) had only a weak excitatory effect. However, test responses to algesic substances were regularly greatly increased by PG-E2, -I2 and 5-HT. Concentrations of PG-E2 of 1.4 X 10(-8) M or greater augmented BK responses; higher concentrations and/or longer applications were needed to enhance responses to algesic salt solutions. Effective concentrations for the PGs and 5-HT were near those reported for inflamed tissues and exudate. Aspirin (ASA) (5.5 X 10(-4) M or greater, for more than 4 min) suppressed the responses to BK but not those evoked by hypertonic saline. The ASA effect on the BK response was largely restored by an addition of PG-E2. Substance P also had a weak excitatory effect on some polymodal receptors, but no significant enhancement of the response to BK was noted. These results further support a role of polymodal receptors in transmitting nociceptive information, of inflammatory origin.

Animals↗