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T Nishimura

Publications and source records attributed to T Nishimura.

At least 973 records · Page 54Linked to original sources

[Laboratory and clinical studies of norfloxacin in pediatric field].

We have carried out laboratory and clinical studies on norfloxacin (NFLX, AM-715). The results are summarized as follows. NFLX was given through oral administration to one child each at dose levels of 1.7 mg/kg, 2.4 mg/kg and 3.2 mg/kg. After administration, peak serum levels of NFLX obtained for the 3 dose levels were 0.16 micrograms/ml at 1 hour, 0.69 micrograms/ml at 2 hours, 0.81 micrograms/ml at 1 hour, respectively, and half-lives were 2.5 hours, 1.8 hours and 2.7 hours, respectively. NFLX was given through oral administration to 2 children at a dose level of 4.4 mg/kg and to another child at a dose level of 4.8 mg/kg. After administration, mean peak serum levels of NFLX obtained were 1.17 +/- 0.48 micrograms/ml and half-lives were 3.0 +/- 0.5 hours. Urinary excretion rates of NFLX were 14.5% and 28.4% in the first 8 hours after administration of 1.7 mg/kg and 3.2 mg/kg, respectively, and 29.1% in the first 6 hours after administration of 2.4 mg/kg. Mean urinary excretion rates of NFLX were 38.5 +/- 13.0% in the first 8 hours after administration of 4.4 mg/kg and 4.8 mg/kg. Treatment with NFLX was made in 33 cases of pediatric bacterial infections including 5 cases of tonsillitis, 14 cases of enteritis, 10 cases of UTI and 1 case each of bronchitis, balanoposthitis, impetigo and pustulosis. Results obtained were excellent in 14 cases, good in 15 cases. No significant side effect due to the drug was observed in any cases.

Adolescent↗

Accumulation of 125I-factor XI in atheroma of rabbit with hereditary hyperlipidemia (WHHL-rabbit).

We have studied the turnover and accumulation of rabbit factor XI (F.XI) in atherosclerotic lesion in Watanabe-hereditable hyperlipidemic rabbit (WHHL rabbit) to reveal the participation of blood coagulation in atherosclerotic lesion. Rabbit F.XI was iodinated and administered intravenously to WHHL rabbits and Japanese white rabbits. The turnover of 125I-rabbit F.XI was significantly faster in WHHL rabbits (T1/2 = 2.84 +/- 0.44 days) than in normal rabbits (T1/2 = 4.44 +/- 0.42 days). The thoracic aorta of WHHL rabbit was strongly labelled with 125I-rabbit F.XI, in sections obtained after 5 days by en-face autoradiography, whereas no radioactivity was detected in normal aorta. By an immunohistochemical study of WHHL rabbit aorta, we confirmed that many F.XI- and fibrin-related compounds existed in the atheroma, whereas albumin did not in these area. These results suggest that the activation of F.XI proceeds on the atherosclerotic lesions of WHHL rabbits.

Animals↗

Frequency dependent inhibition of the nicotinic transmission by serotonin in vesical pelvic ganglia of the rabbit.

Intracellular recordings were made from neurons in rabbit vesical pelvic ganglia (VPG), in vitro. Increasing the frequency of preganglionic-nerve stimulations from 0.1-1 Hz to 10-20 Hz facilitated fast excitatory postsynaptic potentials (EPSPs), resulting in a generation of action potentials. Acetylcholine-induced response was not altered during the facilitation of the fast EPSP. Serotonin blocked action potentials elicited by preganglionic-nerve stimulations at 0.1 Hz, while it caused no blockade at 10 Hz. Serotonin may potentiate the feature of high-pass filter in transmission of VPG. Immunohistochemical study demonstrated serotonin-like varicose terminals in rabbit VPG.

Acetylcholine↗

A nucleotide phosphodiesterase with preference for 2',5'-phosphodiester bonds from Ehrlich ascites carcinoma.

We have previously reported that many tumor cell lines express a 5'-nucleotide phosphodiesterase (phosphodiesterase I, EC 3.1.4.1) with properties clearly distinguishable from enzymes of normal tissues (Biochim. Biophys. Acta (1988) 966, 99-106). Such an enzyme with 5'-nucleotide phosphodiesterase activity was purified from Ehrlich ascites carcinoma by measuring the cleavage of thymidine 5'-monophosphate p-nitrophenyl ester (TMP-NP). The enzyme is a soluble protein, has a pH optimum of 7.5, and the molecular mass estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 67 kDa. The enzyme does not hydrolyze other chromogenic substrates for phosphodiesterases, nor pyrophosphate bond of various nucleotides which are cleaved by 5'-nucleotide phosphodiesterases of normal tissues. But, it hydrolyzes dinucleotides to form 5'-phosphates, and is more active on 2',5'- than on 3',5'-phosphodiester bonds. These results indicate that the TMP-NP splitting enzyme in Ehrlich ascites carcinoma cells is a 2',5'-phosphodiesterase.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗

Inhibition of lymphokine-activated killer cell-mediated cytotoxicity by phorbol ester.

As previously reported, the culture of mouse spleen cells in the presence of high amounts of human rIL-2 for 4 days caused proliferation and generation of lymphokine-activated killer (LAK) cells, which could lyse a variety of tumor cells. However, an addition of PMA to the culture resulted in a striking inhibition of the generation of LAK cells. In contrast, IL-2-induced cell proliferation, IL-2R expression, and LFA-1 expression were enhanced by the addition of PMA. Kinetic studies revealed that the addition of PMA during the final 24 h, but not 4 h, of the culture was sufficient to inhibit the generation of LAK cells. The same inhibition of LAK activity was observed when 4-day cultured LAK cells were pretreated with PMA for over 12 h before cytotoxicity assay. Flow cytometry analysis showed that PMA pretreatment had no effect on the binding of LAK cells to target cells. PMA pretreatment of LAK cells caused total disappearance of protein kinase C (PKC) activity from LAK cells concomitant with the loss of LAK activity. However, PMA-pretreated LAK cells cultured for another 24 h in the absence of PMA revealed levels of PKC activity and cytotoxicity identical with untreated LAK cells. These results strongly suggest that PMA-induced down-regulation of LAK cell-mediated cytotoxicity is due to the inactivation of PKC-dependent transduction systems that are essential post LAK cell-target cell binding.

Animals↗

Lysosome instability in aged rat brain.

The study of the age-dependent change in lysosomal enzyme activities of the cerebral tissue showed the significant increase of cathepsin D in the aged rat brain, while those of beta-glucuronidase and acid phosphatase remained unchanged. The subcellular distribution study of cathepsin D and beta-glucuronidase revealed the increased activity of these enzymes in the cytosolic fraction from the aged brain. In vitro incubation of the lysosome fraction from the aged rat brain resulted in more leakage of these two enzymes, indicating the instability of the lysosome in the aged brain, which resembled the effect of L-Leu-methyl ester to the lysosome.

Aging↗

Cerebral vascular malformations: applications of magnetic resonance imaging to differential diagnosis.

Twelve patients with cerebral vascular malformations (5 cavernous angiomas, 1 thrombosed arteriovenous malformation, and 6 venous angiomas) were studied with magnetic resonance (MR) imaging. All lesions were clearly depicted. Characteristic MR findings were obtained mainly on T2-weighted images: a markedly low intensity area was always seen. The margins of arteriovenous malformation (AVM) and venous angioma were irregular while those of cavernous angioma were smooth in all planes on T2-weighted images. Gradient-echo (GrE) pulse sequences were more sensitive than T2-weighted spin echo (SE) in lesion detection. MR imaging could play an important role in the differential diagnosis of cerebral vascular malformations.

Adult↗

Fatty acid myocardial imaging using 123I-beta-methyl-iodophenyl pentadecanoic acid (BMIPP): comparison of myocardial perfusion and fatty acid utilization in canine myocardial infarction (occlusion and reperfusion model).

To evaluate the relationship between myocardial perfusion and fatty acid metabolism in canine myocardial infarction, 16 dogs were studied using thallium and 123I-beta-methyl-iodophenyl pentadecanoic acid (BMIPP). Eight dogs (group A) had left anterior coronary arterial occlusion (6 h ligation), 6 dogs (group B) had reperfusion (3 h ligation and 1 h reperfusion) and 2 dogs served as the normal control. Myocardial imaging with BMIPP was excellent, owing to its higher uptake and longer retention in myocardium and rapid blood disappearance in addition to diminished liver and lung uptake. The mean half time value which was generated from the BMIPP myocardial washout curve, was significantly larger in the reperfused myocardium. The gamma camera imaging showed uncoupling of BMIPP and thallium (BMIPP uptake greater than thallium uptake) in five dogs in group B. On the other hand, all dogs in group A had a persistent defect in BMIPP and thallium uptake. Our findings indicate that the combination of BMIPP and thallium for myocardial imaging supply different information about the zone of infarction and ischemia, which may be useful for the assessment of myocardial viability.

Animals↗

First trimester prenatal diagnosis of haemophilia A using factor VIII gene probe.

Accurate first-trimester prenatal diagnosis was achieved in a Japanese haemophilia A family by the use of a restriction fragment length polymorphism (RFLP) located within the F.VIII gene. Since the pregnant woman's heterozygosity for BclI polymorphism in F.VIII/intron 18 (F8A) probe was informative, chorionic villus sampling (CVS) was performed at 9 weeks of gestation. Restriction analysis showed that the fetus was heterozygous for the BclI site and had received a normal paternal X chromosome (0.9 kb) and a normal maternal X (1.2 kb). Therefore, we concluded that the fetus was a non-carrier female. Pregnancy went to term and woman gave birth to an apparently healthy female. At one week after birth a coagulation study confirmed that the newborn infant is not a carrier. The first-trimester prenatal diagnosis of haemophilia A is possible by CVS due to a RFLP in the F.VIII gene.

Blotting, Southern↗

Anti-idiotype antibody reactive with a target molecule for mouse lymphokine-activated killer cells.

A rat monoclonal antibody (MoAb), termed KBA, against mouse lymphokine-activated killer (LAK) cells recognizes a LAK cell surface molecule termed LAA responsible for the binding between LAK and target cells. In order to identify a target molecule of LAK cells, we prepared anti-KBA idiotype antibodies (anti-KBA-Id) from rabbit anti-KBA sera. Immunoglobulins were separated by ammonium sulfate precipitation followed by sequential affinity column chromatographies using Affi-gel coupled with rat MoAbs other than KBA and KBA-coupled gel. An immunoglobulin(s) in a KBA-gel-bound fraction showed the selective reactivity to KBA, comprising anti-KBA-Id character. This anti-KBA-Id inhibited the binding of KBA to LAK. Moreover, it bound with a portion of mouse leukemia cells sensitive to LAK cells, but not with normal mouse cells, and inhibited the binding of LAK cells to a target leukemia. These findings indicate that the anti-KBA-Id contain anti-Id which possess a three-dimensional structure that mimics a mirror image of the antigen (LAA)-combining site in KBA or the structure of LAA. The antigen reactive with anti-KBA-Id was characterized as a glycoprotein.

Animals↗

Synthesis of 11 alpha-hydroxyprogesterone haptens.

C-4 and C-6 bridged haptens of 11 alpha-hydroxyprogesterone, an anti-androgen, were respectively synthesized via 4, 5 and 5 alpha, 6 alpha epoxide ring openings using 3-mercaptopropanoic acid. Substitution of 6-bromo derivative of progesterone using the same reagent unexpectedly afforded a C-4 substituted product instead of the normal C-6 substituted product previously reported in the literature.

Chemical Phenomena↗

Age-dependent change in activities of lysosomal enzymes in rat brain.

The age-dependent change in activities of seven lysosomal enzymes (cathepsin D, beta-glucuronidase, acid phosphatase, acid/alkaline DNases and acid/alkaline RNases) was studied in four brain regions (cerebrum, hippocampus, pons and cerebellum) of Wistar rats. The activity of cathepsin D was significantly increased with aging in the four regions. The age-dependent change in activities of acid and alkaline DNases showed the characteristic regional difference, and the ratio of acid to alkaline DNases was increased with aging in all regions. Acid RNase showed the lowest activity in 18-month-old rats, and alkaline RNase activity was decreased with aging. The activity of beta-glucuronidase was higher in 2-month-old rats in all of the regions studied. Acid phosphatase showed no significant age-dependent change except in pons. The study demonstrated that all of the lysosomal enzyme activities do not change in parallel with aging, and that the age-dependent change showed the characteristic regional difference.

Acid Phosphatase↗

5-Hydroxytryptamine produces presynaptic facilitation of cholinergic transmission in rabbit parasympathetic ganglia.

Intracellular recordings were made from neurons of rabbit vesical pelvic (parasympathetic) ganglia (VPG). Application of 5-hydroxytryptamine (5-HT, 0.3-30 microM) produced an initial depression followed by a long-lasting facilitation of the fast excitatory postsynaptic potential (e.p.s.p.) evoked by stimulation of the pelvic preganglionic nerve. The facilitation of nicotinic transmission lasted for 30-120 min, even when 5-HT was removed from the superfusing solution. 5-HT (0.3-30 microM) did not change the depolarization induced by a direct application of acetylcholine (ACh) to the VPG neurons pretreated with 1 microM atropine. 5-HT also caused an initial depression followed by an increase in the quantal content of the fast e.p.s.p. It is, therefore, suggested that diphasic effect of 5-HT on the nicotinic transmission is due mainly to a modulation of the ACh-release from presynaptic nerve terminals. Methysergide (5 microM), mianserin (5-30 microM) and ICS 205-930 (100-300 nM) did not antagonize the presynaptic actions of 5-HT on the nicotinic transmission, suggesting that the presynaptic 5-HT receptor may belong to a class of 5-HT1 subtypes. Spiperone (1 microM), a selective 5-HT1A antagonist, blocked the 5-HT-induced inhibition of the fast e.p.s.p. Under the effect of spiperone, the facilitation appeared soon after application of 5-HT. The facilitation of the fast e.p.s.p. may be mediated through a 5-HT1B or 5-HT1C subtype. Lowering temperature of the external solution eliminated the 5-HT-induced facilitation of the nicotinic transmission. Forskolin produced a presynaptic facilitation of the fast e.p.s.p., without producing an initial depression. 3-Isobutyl-1-methylxanthine (10 microM) potentiated the facilitatory action of 5-HT. Bath-application of dibutyryl cyclic adenosine monophosphate (cAMP) (1-6 mM) and 8-bromo-cyclic AMP (2-5 mM) mimicked the effect of 5-HT in producing the facilitation of the fast e.p.s.p.s. All data presented are consistent with the hypothesis that 5-HT, acting on presynaptic 5-HT1 receptors, causes a facilitation in the release of ACh from preganglionic nerve terminals possibly mediated through an activation of adenylate cyclase.

Acetylcholine↗

Hemodynamic and prognostic value of thallium-201 myocardial imaging in patients with dilated cardiomyopathy.

We studied 70 patients with dilated cardiomyopathy to determine whether extent of perfusion defect on thallium imaging could be related to the hemodynamics and prognosis of the patients. Patients were divided into three groups according to the extent of perfusion defect, i.e., Grade I: no perfusion defect (n = 19), Grade II: apical perfusion defect (n = 22), and Grade III: extensive perfusion defect (n = 29). The patients of Grade III demonstrated marked hemodynamic deterioration compared with those of Grade I and II. Three-year survival rate showed lower value in proportion to the extent of perfusion defect (P less than 0.05). Death from progressive heart failure tended to occur in patients with extensive perfusion defect (P less than 0.05). In patients of Grade III, the perfusion defect extended mainly to the posterolateral segment. Although autopsy studies showed increased fibrosis in the left ventricular wall in these patients, the extension of the fibrosis was not related to that of fibrosis. Moreover, the perfusion defect had regressed in three of 18 patients in the follow-up examination. These results indicate that the extent of perfusion defect on thallium imaging may be of value in non-invasive evaluation and prediction of the prognosis in patients with dilated cardiomyopathy. Distribution of the perfusion defect was, however, not related to that of myocardial fibrosis.

Adolescent↗

Agenesis of the cervical internal carotid artery.

Total or segmental agenesis of the internal carotid artery is a rare anomaly. The cervical portion of the internal carotid artery was absent in the right side of the patient who was carried out radical surgery due to recurrent oropharyngeal cancer. Post-operative venous digital subtraction angiography revealed that the remaining intracranial portion of the internal carotid artery was normally patent and supplied blood flow via ipsilateral external carotid artery. Otolaryngologist-Head and Neck surgeon should know such a vascular anomaly and avoid a disastrous result on dividing the external carotid artery.

Carotid Artery, Internal↗

Sodium nuclear magnetic resonance imaging of acute cardiac rejection in heterotopic heart transplantation.

Nuclear magnetic resonance (NMR) imaging was used to measure tissue sodium-23 in the myocardium undergoing cardiac rejection. In six dogs, the donor heart was heterotopically transplanted into the recipient's chest cavity. The dogs were then killed and sodium-23 images of the excised hearts were obtained using a high field (1.5 Tesla) NMR imaging system. Proton NMR imaging of each excised heart was also performed and T1, T2 relaxation times were calculated. Subsequently, these data were correlated with pathological findings of mild, moderate and severe rejection. The correlation coefficients between the rejection score and the T1, T2 relaxation times and sodium NMR signal intensity were 0.79, 0.70 and 0.84, respectively. Severely rejected areas of the myocardium were visualised by increased sodium NMR signals. These findings suggest that an increase of sodium NMR intensity is mainly caused by an increase of intracellular sodium content due to irreversible myocardial necrosis. Sodium NMR allows evaluation of the location and extent of rejection of myocardium after heart transplantation.

Animals↗

Lysis of human leukemic cells by monocyte-derived macrophages activated with interferon-gamma and interleukin-2.

Cytolysis of leukemic cells by peripheral blood-derived macrophages was examined by means of an in vitro 111In release assay. Monocytes prepared on culture dishes lyse YK-M2. However, when monocytes were cultured in vitro and transformed into macrophages, they lost most of their lytic activity. The addition of human recombinant interleukin-2 (rIL-2) on day 5 in culture enhanced the lytic activity significantly. Similarly, treatment of macrophages with human recombinant interferon gamma (rIFN-gamma) promoted the lysis of YK-M2 and K-562, although the extent of lysis was smaller than that by rIL-2. Macrophages activated with rIL-2 and rIFN-gamma also lysed human leukemic cells. Activated macrophages lysed leukemic cells of acute myelocytic leukemia more than acute lymphocytic leukemia cells. Macrophages derived from the peripheral blood of patients with leukemia were examined for their lytic activity against YK-M2. The patient's macrophages lysed more YK-M2 than did control macrophages when they were activated with rIL-2 and rIFN-gamma. The macrophages of two patients also demonstrated autologous leukemic cell lysis.

Adolescent↗

Inhibition of intracellular bleomycin hydrolase activity by E-64 leads to the potentiation of the cytotoxicity of peplomycin against Chinese hamster lung cells.

N-(N-(L-3-trans-carboxyoxiran-2-carbonyl)-L-leucyl)-agmatine (E-64), a thiol protease inhibitor, potentiated the cytotoxicity of peplomycin against the Chinese hamster lung (V79) cell. After the treatment of the cells with E-64 (50 micrograms/ml) for 12 h, bleomycin hydrolase activity of the cells was almost completely inhibited. V79 cells treated with [3H]peplomycin for 24 h in the presence of E-64 (50 micrograms/ml) accumulated twice as much [3H]peplomycin and five times less [3H]desamidopeplomycin compared with V79 cells treated in the absence of E-64. These results suggest that E-64 increases the sensitivity of V79 cells to peplomycin probably by inhibiting the intracellular bleomycin hydrolase activity.

Animals↗