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Biomedical subjects

K Sasaki

Publications and source records attributed to K Sasaki.

At least 19 recordsLinked to original sources

Protection by chlorpromazine against lethality and renal toxicity of cisplatin in mice.

The effect of chlorpromazine on acute lethal toxicity and nephrotoxicity induced by cisplatin was studied in mice. Chlorpromazine given (i.p.) 1 h before cisplatin greatly reduced lethal and renal toxicities of cisplatin. Chlorpromazine did not reduce the antitumor activity of cisplatin against Sarcoma 180 in ddY mice or EL-4 Leukemia in C57BL/6J mice.

Animals

Identification of a soluble GM-CSF binding protein in the supernatant of a human choriocarcinoma cell line.

We identified two forms of the receptor for granulocyte-macrophage colony-stimulating factor (GM-CSF) made by the human choriocarcinoma cell line JEG-3 using an affinity-labeling technique. The protein was identified in the detergent-extract was 78 kDa, very similar to that of the membrane-bound GM-CSF receptor alpha chain expressed in a wide variety of hematopoietic and nonhematopoietic cells, including JEG-3. In contrast, a 62-kDa GM-CSF binding protein, or the soluble GM-CSF receptor, was identified in the supernatant of JEG-3 cells. Utilizing the same affinity labeling technique, we did not detect the soluble GM-CSF binding protein in the supernatant of several hematopoietic cell lines, such as U-937 and KG-1, which express membrane bound alpha chain as well as beta chain. The 62-kDa soluble GM-CSF receptor is produced in abundant amounts by JEG-3, but in very small amounts, if any, by hematopoietic cell lines.

Choriocarcinoma

Radiographic analysis of the arteries of human lumbar lymph nodes.

Twenty-seven cadavers (12 male, 15 female aged 28 to 94 years, average 75 years) were dissected to analyze the arterial supply of the lumbar lymph nodes with angiography and an image processor-analyzer. The lymph nodes on the left side of the abdominal aorta fused to form several elongated nodes. The lymph nodes on the right side remained separated. A few lymph nodes aggregated below the bifurcation of the abdominal aorta. They received a few branches directly from the abdominal aorta or from the renal, gonadal and/or iliac arteries, which anastomosed with each other to form an arterial arc. This anastomosis gave small paired twigs to the parenchyma continuously. In the case of well developed lymph nodes dorsal to the inferior vena cava, a vessel from the lower abdominal aorta passed upward to supply them. The diameter of these vessels in the angiogram was 0.09-0.27 mm, measured with the image processor-analyzer. These results show that the lumbar lymph nodes do not receive a single artery through the hilus, but through several branches, whose anastomoses form a collateral system associated with the abdominal aorta.

Adult

Disposition of beta-hexachlorocyclohexane, p,p'-DDT, and trans-chlordane administered subcutaneously to monkeys (Macaca fascicularis).

To evaluate skin lipid analysis for the accumulation level of environmental pollutants, the correlations between organochlorine pesticide residues in adipose tissue, blood, and skin lipids of monkeys were studied. The mixture of beta-hexachlorocyclohexane (beta-HCH), p,p'-DDT, and trans-chlordane was subcutaneously given to monkeys once weekly for 5 weeks at dose levels of 1 and 10 mg/kg. The chemicals distributed in adipose tissue, blood, and skin lipids were determined six times after the last dosing at intervals of 4 to 9 weeks. Oxychlordane and p,p'-DDE were detected in all tissues together with the administered chemicals. In blood and adipose tissue, trans-chlordane decreased rapidly and oxychlordane and p,p'-DDE increased gradually and then remained at constant levels. beta-HCH and p,p'-DDT in adipose tissue increased until the 12th week and then decreased in all animals. The correlation coefficients between blood and adipose tissue regardless of dose level and collection time for each chemical ranged from 0.83 to 0.94. Correlation coefficients between skin lipids and adipose tissue varied with the chemical, namely, 0.31, 0.72, 0.81, 0.81, and 0.83 for p,p'-DDE, trans-chlordane, p,p'-DDT, beta-HCH, and oxychlordane, respectively. The results indicated that skin lipid analysis may be useful for the evaluation of specific pollutants in the body burden.

Adipose Tissue

A prospective randomized study of prophylaxis of tumor recurrence following transurethral resection of superficial bladder cancer--intravesical thio-TEPA versus oral UFT.

The long-term prophylactic effect of chemotherapy following transurethral electroresection of bladder tumors (TUR-Bt) was investigated using three different modalities: no prophylactic treatment (group C); oral UFT given at 1296 mg/day for 2 years (group U); and intravesical thio-TEPA at 30 mg/30 ml physiological saline, instilled 32 times over 2 years (group T). Patients newly diagnosed as having superficial bladder cancer (stage, less than or equal to pT1b; grade, less than or equal to G2) who had undergone TUR-Bt at Nara Medical University and its affiliated hospitals between November 1986 and March 1990 were allocated to one of the three groups by the envelope method. The initial treatment was maintained until the third recurrence or disease progression, except for TUR-Bt which was performed at the time of recurrence. The registered cases included 51 patients in group C, 50 in group U, and 52 in group T, and the number of evaluable cases in each group were 48, 47, and 45, respectively. The non-recurrence rates at 3 years were 54% in group C, 67% in group U, and 85% in group T, and the difference between groups T and C was significant. In terms of the tumor grade and stage, No significant difference was observed among the groups in the category of G1 or Ta tumors, but the non-recurrence rates determined in group T for G2 or T1 tumors were significantly higher than those obtained in group C. Moreover, no significant difference was found among the groups in relation to solitary tumors, but the non-recurrence rate obtained in group T for multiple tumors was significantly higher than that determined in group C. The overall cumulative recurrence rate in each group was 3.07 in group C, 1.95 in group U, and 0.70 in group T, and that determined according to tumor grade, stage, and multiplicity was also highest in group C, followed by group U and group T. The main adverse effects encountered were upper gastrointestinal (GI) symptoms (8.5%) in group U and irritable bladder (11.1%) in group T. Intravesical instillation of thio-TEPA tended to produce greater preventive efficacy than did oral UFT during the early postoperative period, but the prophylactic efficacy of thio-TEPA and UFT should be elucidated over a longer observation period.

Administration, Intravesical

Regulation of G418 selection efficiency by cell-cell interaction in transfection.

We attempted to establish the optimum conditions for the calcium phosphate (CaPO4) precipitation protocol by counting G418 resistant (G418r) colonies after transfection of pSV2-neo DNA into BALB 3T3 cells. The amount and molecular size of carrier DNA, number of plating cells, treatment period of DNA-CaPO4 precipitates and expression time of G418 selection were found to be important factors in the induction of G418r colonies. Six G418r clones were derived from BALB 3T3, NIH 3T3 and FRSK cells, and cocultured with G418 sensitive (G418s) parent cells in G418 medium. The colony formation capacity of all G418r cell clones decreased with the increasing number of plated G418s cells. Cell-cell contact appeared to be necessary to reduce the colony formation of G418r cells, and contact-dependent G418r cell killing was probably not related to gap junction formation. Contact-mediated cell killing is a likely explanation for the observation that induction of G418r colonies is often reduced under conditions of high-density plating, long treatment of DNA-CaPO4 precipitates, and long expression time of G418 selection. These results suggest that in some instances transfection efficiency using pSV2-neo DNA should be carefully evaluated because culture conditions can mask the induction of G418r colonies.

Animals

Proliferating cell nuclear antigen in malignant and pre-malignant lesions of epithelial origin in the oral cavity and the skin: an immunohistochemical study.

Proliferating cell nuclear antigen (PCNA) is a nuclear protein synthesized in the late G1 and S phase of the cell cycle and immunohistochemical detection of the protein represents a useful marker for the proliferating fraction of cells in tissue specimens. A series of malignant and pre-malignant lesions of the oral cavity and skin were evaluated by the streptavidin biotin immunoperoxidase method for detection of this protein. Monoclonal anti-PCNA antibody (PC 10) labelled proliferating cells in all cases with varying intensity of nuclear staining. In squamous cell carcinoma (n = 48), PCNA positivity correlated with the differentiation and atypia of the tumour cells; however, in poorly differentiated tumours, the relationship between PCNA expression and proliferation was lost. Basal cell carcinoma showed an increased growth fraction in tiny epithelial nests (mean 43.8, SD 6.0, n = 20) than in neoplastic basal cells (mean 30.1, SD 6.9, n = 8). The growth fractions were significantly higher in the pre-malignant lesions (leukoplakia, mean 22.3, SD 7.7, n = 14; Bowen's disease, mean 45.2, SD 11.7, n = 12; senile keratosis, mean 41.2, SD 7.0, n = 12) than in the normal mucosa (mean 9.8, SD 4.9, n = 10), suggesting that cellular growth fractions correlate with the degree of dysplasia in pre-malignant lesions.

Antibodies, Monoclonal

Cytochrome b positive X-linked chronic granulomatous disease: a normal cell surface expression of cytochrome b.

The polymorphonuclear (PMN) cells from a patient with cytochrome b positive X-linked chronic granulomatous disease (Xb+ CGD) were studied using flow cytometry. Both the cell surface expression of monoclonal antibody defined cytochrome b and the superoxide production (intracellular 2',7'-Dichlorofluorescin Diacetate oxidation) were investigated at a single cell level. Flow cytometry clearly demonstrated the complete absence of superoxide production in the patient's PMN cells, the mosaicism in his mother's PMN cells and also indicated the normal cell surface expression of cytochrome b. The results obtained by Western blot analysis and reduced-minus-oxidized spectra confirmed the presence of functional and normal amounts of cytochrome b. We concluded that this is a case of Xb+ CGD with a normal cell surface expression of cytochrome b.

Adolescent

Amplification and overexpression of the c-erbB-2 protooncogene in human gastric cancer.

The c-erbB-2 protooncogene encodes a possible growth factor receptor. This gene has been studied as to whether it can be regarded as a prognostic indicator in human breast carcinoma. As amplification and overexpression of the gene have been reported in several adenocarcinomas, 24 specimens of human gastric cancers were examined by immunohistochemical staining (24 cases), by Southern blotting (23/24) and by Northern blotting (16/24). Amplification of the gene was detected in two moderately differentiated tubular adenocarcinomas (8.7%), and overexpression of c-erbB-2 mRNA was detected in three moderately differentiated tubular adenocarcinomas (18.8%). By immunohistochemical staining of paraffin-embedded tissues using a polyclonal antibody to c-erbB-2 gene products, the cell membrane was stained positively in three cases of gastric cancers which overexpressed c-erbB-2 mRNA. Peritoneal metastases were found in six gastric cancers, including two moderately differentiated tubular adenocarcinomas in which amplification of c-erbB-2 occurred. These results suggest that amplification and overexpression of c-erbB-2 may be correlated with metastases in differentiated adenocarcinoma of the stomach.

Adenocarcinoma

Patchy distribution of rejection changes in small intestinal transplantation.

The aim of this study is to determine the distribution of histological changes of rejection in small intestinal transplantation. Thirty-nine rats were randomized into two groups: group I (n = 15), syngeneic transplants and group II (n = 24), allogeneic transplants. Grafts were excised and examined on days 2, 4, and 8 after transplantation. All grafts of the syngeneic group showed normal mucosa by day 4. However, by this time, all grafts of the allogeneic group demonstrated rejection changes with a patchy distribution in the mucosa. Therefore, with a biopsy from the stoma site there is a risk of missing early rejection.

Animals

Acute myelocytic leukemia associated with thrombocytosis and inv 3(q21.3; q26.2) in a case of Grönbland-Strandberg syndrome.

Grönbland-Strandberg syndrome is an inherited connective tissue disorder with cutaneous, ophthalmologic, and systemic manifestations. Here we report a case of AML with thrombocytosis arising in a patient with this syndrome. Karyotypic analysis of bone marrow cells revealed the inversion 3 (q21.3;q26.2). To our knowledge, this is the first report of the association of AML with thrombocytosis and Grönbland-Strandberg syndrome. This might be a coincidental association, but it suggests some interesting speculations regarding the pathogenesis of these diseases.

Chromosome Inversion

G-protein mediating the slow depolarization induced by FMRFamide in the ganglion cells of Aplysia.

Application of FMRFamide (Phe-Met-Arg-Phe-NH2) induced a slow depolarization in neurons of the Aplysia abdominal ganglion. In voltage-clamped cells, FMRFamide induced a slow inward current that increased when the membrane was depolarized beyond -85 mV, showing a negative slope conductance. However, this inward current never reversed to outward current when hyperpolarized beyond the equilibrium potential for K+. The FMRFamide-induced response was markedly augmented in Ca(2+)-free media, but depressed in Na(+)-free media. It was unaffected by a change in external potassium. Intracellular injection of guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) significantly depressed the FMRFamide response in a dose-dependent way. Injection of cholera toxin (CTX) which did not cause any current response, selectively and irreversibly blocked the FMRFamide response. Neither 3'-deoxyadenosine, an inhibitor of adenylate cyclase, nor H-8, an inhibitor of cyclic adenosine 3',5'-monophosphate (cyclic AMP)-dependent kinase, depressed the FMRFamide response. 3-Isobutyl-1-methylxanthine (IBMX) did not augment the FMRFamide response appreciably. The FMRFamide response was not occluded at all by a relatively large injection of 8-bromo-cyclic AMP. It was concluded that the FMRFamide response is produced by the opening of the voltage-dependent Na(+)-channels via activation of a certain CTX-sensitive G-protein which is different from conventional "Gs" that activates adenylate cyclase.

1-Methyl-3-isobutylxanthine

An autoradiographic study of cortical projections from motor thalamic nuclei in the macaque monkey.

The special areal and laminar distributions of cortical afferent connections from various thalamic nuclei in the monkey (Macaca fuscata) were studied by using the anterograde axonal transport technique of autoradiography. The following findings were obtained. The superficial thalamocortical (T-C) projections, terminating in the (superficial half of) cortical layer I, arise mainly from the nucleus ventralis anterior, pars principalis (VApc) and nucleus ventralis lateralis, pars oralis (VLo), and possibly from the nucleus ventralis lateralis, pars medialis (VLm) and nucleus ventralis anterior, pars magnocellularis (VAmc). The VApc gives rise to the superficial T-C and deep T-C projections onto the postarcuate premotor area around the arcuate genu and spur, and onto the dorsomedial part of the caudal premotor area as well as the supplementary motor area (SMA). The VApc also gives rise to only deep T-C projections onto the remaining premotor area and onto the rostral bank of the arcuate sulcus as well as the ventral bank of the cingulate sulcus at the level of the premotor area. The VLo gives rise to the superficial T-C projections onto the ventrolateral part of the motor area (mainly to the forelimb motor area) and onto the dorsomedial part to the mesial cortex at the rostral level of the motor area. The VAmc gives rise to the superficial T-C projections onto the banks of the arcuate genu and adjacent region of area 8. Area X, the nucleus ventralis posterolateralis, pars oralis (VPLo), nucleus ventralis posterolateralis, pars caudalis (VPLc), nucleus ventralis posteromedialis (VPM) and possibly the nucleus ventralis lateralis, pars caudalis (VLc) send only deep T-C projections. The dorsal and medial parts of the VLc project onto the premotor area, the rostral part of the motor area and the SMA, and also the ventral bank of the cingulate sulcus. Area X projects onto the premotor area, the SMA, and the caudal part of area 8. The thalamic relay nuclei projecting onto the frontal association cortex were found to be the VAmc, medial VLc and area X.

Afferent Pathways

Biological activity of subfractions from scrapie-associated fibrils.

Subfractions, a nucleic acid fraction and a PrP fraction consisting of PrP17-25, a core fragment of PrPsc, were prepared from the scrapie-associated fibril-enriched fraction from scapie-affected mouse brains. The nucleic acid fraction consisted mainly of variously fragmented DNA and no scrapie-specific nucleic acid was detected in the fraction by SDS polyacrylamide gel electrophoresis. To examine the biological activity, the nucleic acid fraction was either first introduced into mouse L-929 cells before or after nuclease treatments, then transfected cell lysates prepared 2 weeks later were inoculated into mice, or directly inoculated into mice with or without the PrP fraction. The PrP fraction alone was also inoculated into mice. Mice inoculated with the transfected cell lysates or with the nucleic acid fraction alone showed no scrapie signs during their lifespan or the observation period. While 60% of the mice inoculated with the PrP fraction alone and 67% of those inoculated with the fraction together with the nucleic acid fraction showed clinical signs of scrapie. A nucleic acid molecule bound covalently to PrP17-25 was not detected. The results obtained by the present procedures so far suggest scrapie infectivity to be associated with PrPsc, which does not contain any detectable scrapie-genome molecule as either free or covalently bound nucleic acid.

Animals

Acidic fibroblast growth factor prevents death of hippocampal CA1 pyramidal cells following ischemia.

Ischemic insult induces neuronal death in the CA1 subfields of the hippocampus which are designated generally as the most vulnerable brain region. Recent studies have shown that acidic and basic fibroblast growth factors are potent trophic factors that support the survival of neurons in many brain regions including the hippocampus. Here we demonstrate that continuous infusion of acidic fibroblast growth factor into the lateral cerebral ventricles beginning 2 days before ischemia prevents the death of the CA1 pyramidal cells in the hippocampus of gerbils. Furthermore, delayed continuous administration of acidic fibroblast growth factor starting 5 min after ischemia is equally protective. The results suggest a possible physiological function for acidic fibroblast growth factor in the normal support of hippocampal CA1 pyramidal cells and neurons in some other brain regions in considering the broad spectrum of responsive neurons.

Animals

Demyelinating peripheral neuropathy in Cockayne syndrome: a histopathologic and morphometric study.

The clinical and histopathological features of Cockayne syndrome in a 2-year-old girl are reported. Sural nerve biopsy revealed segmental demyelination and remyelination. The density of myelinated fibers, especially small ones, was decreased in comparison with an age-matched control. Although the total number of unmyelinated fibers showed no difference from that in the control, the number of small unmyelinated fibers was slightly increased. A study of teased fibers from the patient's nerve revealed that 1% of the fibers had segmental demyelination, and 7% showed remyelination. Ultrastructurally, demyelinated fibers were present sporadically. No degeneration of axons was evident. Our pathological and morphometric data for the sural nerve suggest the presence of primary demyelination in early childhood.

Child, Preschool

Measurement of proliferating cell nuclear antigen (PCNA) and its clinical application in oral cancers.

The PCNA score was measured in oral squamous cell carcinoma (SCC), and its relationship to other cell proliferation markers, Ki-67 score, S-phase fraction (SPF), and AgNORs counts was investigated. The PCNA score ranged from 0.4% to 43.5% with an average value of 22.8%, the Ki-67 score ranged from 4.9% to 40% with an average of 24.1%, and the SPF ranged from 0.4% to 32.5% with an average of 12.4%, while AgNORs counts ranged from 2.53/nucleus to 7.03/nucleus with an average of 4.74/nucleus. These four parameters were closely interrelated. There was a significant difference in PCNA score between malignant and nonmalignant lesions, suggesting a difference in growth activity. The mean PCNA score decreased significantly from 20.0% to 8.0% after cancer chemotherapy. The response of cancer cells to anticancer agents may be estimated by consecutive measurement of PCNA, since the PCNA score dropped after treatment in cases showing a favorable prognosis.

Antigens

A new brain glucosensor and its physiological significance.

The concentration of fibroblast growth factor (FGF), which is found in cerebrospinal fluid (CSF), markedly increases after the start of feeding. Food intake was dose-dependently suppressed by picomole doses of FGF and facilitated by anti-FGF antibody. This suppression was caused by activation of protein kinase C in glucose-sensitive neurons in the lateral hypothalamus. In situ hybridization by use of cDNA showed that acidic (a)FGF was produced in ependymal cells. The ependymal cells released aFGF by responding to glucose increase in CSF after feeding. Released aFGF diffused into the brain parenchyma and was taken by neurons. Passive avoidance was significantly more reliable after aFGF infusion into CSF. Clamping cerebral arteries in the gerbil induced ischemia, which damaged neurons in the CA1 layer of the hippocampus. Pretreatment with aFGF prevented this damage. Thus, aFGF is not only the most potent substance yet found for the suppression of feeding, but it is also extremely effective as a neurotrophic and memory facilitating substance.

Animals