Removal of a press-through package in the thoracic esophagus using two flexible endoscopes.
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Aged↗
Biomedical subjects
K Takada
Publications and source records attributed to K Takada.
Effects of midazolam and flunitrazepam on the release of dopamine from rat striatum measured by in vivo microdialysis.
We have studied the effects of midazolam and flunitrazepam on extracellular concentrations of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in rat striatum in freely moving animals using in vivo microdialysis. I.v. injections of midazolam 0.075 and 0.15 mg kg-1 decreased striatal dopamine concentrations in a dose-dependent manner without affecting the concentrations of DOPAC and HVA. Flunitrazepam 0.015 and 0.03 mg kg-1 also decreased striatal dopamine concentrations in a dose-related manner, but the reductions in DOPAC and HVA were not significant. Flumazenil 6 micrograms kg-1 alone did not affect striatal concentrations of dopamine, DOPAC and HVA, but it prevented the effects of midazolam and flunitrazepam. Flunitrazepam 10 mumol litre-1 also decreased striatal dopamine release when infused through a dialysis probe placed into the striatum, but it failed to affect striatal dopamine release when infused into the ipsilateral substantia nigra. Central administrations of midazolam were effective only when the drug was infused into both sites simultaneously (10 and 100 mumol litre-1) or given by intraventricular injection (0.5 and 1 micrograms). These results suggest that midazolam and flunitrazepam affect striatal dopamine release in a different manner.
3,4-Dihydroxyphenylacetic Acid↗
Changes in dentofacial morphology in skeletal Class III children treated by a modified maxillary protraction headgear and a chin cup: a longitudinal cephalometric appraisal.
The purpose of the current report was to investigate cephalometrically possible orthopaedic effects of a modified maxillary protraction headgear (MPH) on dentofacial morphology in skeletal Class III female patients before and during the pubertal growth spurt period. Sixty-one patients were divided into three groups, the prepubertal (7-10 years, n = 20), the mid-pubertal (10-12 years, n = 22), and the late pubertal (12-15 years, n = 19) groups. Longitudinal record sets of subjects with acceptable good occlusion were used as the control. Patients were treated by protracting from the upper canine area. The mean ages at completion of the MPH treatment were 8.9, 11.3, and 13.3 years for the three test groups, respectively. The average treatment time was 1.1, 1.0, and 1.4 years for each of these groups. Lateral cephalograms at the start and completion of use of the MPH were collected. Annual differences were calculated from these paired records for each of 21 dentoskeletal variables in the test groups and compared to those of the control group. The pre- and mid-pubertal groups revealed significant increases in both the SNA (P < 0.01 and P < 0.001) and the maxillary length (Ptm-A/PP, P < 0.01), while the late pubertal group showed a less significant increase in the SNA (P < 0.05) alone. The decreased SNB, increased ANB and SNMP of the pre- and mid-pubertal groups was accounted for by the backward and downward rotation of the mandible. The results suggest possible orthopaedic effects of the MPH on dentofacial morphology in young females when it is applied before or during acceleration of the pubertal growth spurt.
Adolescent↗
Comparative efficacy of antiarrhythmic agents in preventing halothane-epinephrine arrhythmias in rats.
BACKGROUND: Because the relative efficacy of antiarrhythmic agents on halothane-epinephrine arrhythmias has not been well characterized, this study was undertaken to comparatively evaluate the antiarrhythmic action of Na(+)-, K(+)- and Ca(2+)-channel blockers on epinephrine-induced ventricular arrhythmias during halothane anesthesia in rats. METHODS: Rats were anesthetized at random with either halothane (1.5%), isoflurane (2.0%), or pentobarbital (50 mg/kg intraperitoneally), and the lungs were mechanically ventilated with oxygen. The rats were studied in three consecutive protocols. Protocol I determined the arrhythmogenic thresholds of epinephrine during the three types of anesthesia in 33 rats. Protocol II determined the arrhythmogenic thresholds of epinephrine during halothane anesthesia in 64 rats receiving saline (control) or one of five antiarrhythmic agents. Protocol III measured the duration of epinephrine-induced arrhythmias during halothane anesthesia in 42 rats receiving saline (control) or one of five antiarrhythmic agents. RESULTS: In protocol I, the arrhythmogenic doses of epinephrine during halothane, isoflurane, or pentobarbital anesthesia were 1.7 +/- 3.2, 11.1 +/- 0.6, and 39.0 +/- 3.9 micrograms/kg, respectively, and the corresponding plasma concentrations were 4.3 +/- 0.8, 103.7 +/- 9.2, and 246.7 +/- 28.9 ng/ml, respectively. In protocol II, the arrhythmogenic doses were similar in rats receiving saline and in those receiving lidocaine. The arrhythmogenic doses in rats receiving verapamil, flecainide (Na(+)- and K(+)-channel blocker), E-4031 (K(+)-channel blocker), or amiodarone(K(+)-channel blocker with Na(+)-, Ca(2+)-, and beta-blocking activity) increased significantly, i.e., 4.2, 4.2, 5.5, and 31.7 times control (P < 0.01). In protocol III, lidocaine had no effect on the duration of arrhythmias. Flecainide, E-4031, and verapamil markedly reduced the duration of arrhythmias induced by epinephrine, 8 micrograms/kg intravenously (P < 0.01), whereas only amiodarone markedly reduced the duration of arrhythmias induced by epinephrine, 16 micrograms/kg intravenously (P < 0.01). CONCLUSIONS: It was concluded that agents with K(+)-channel blocking properties were the most effective in preventing halothane-epinephrine arrhythmias in rats.
Amiodarone↗
Effect of local anaesthetics on the stimulus-secretion coupling in bovine adrenal chromaffin cells.
This study was carried out to determine the relative potencies of local anesthetics to inhibit the cholinergic synaptic transmission using cultured bovine adrenal chromaffin cells, and to clarify if the inhibitory action would correlate with biophysical and pharmacological properties. Local anaesthetics (bupivacaine, etidocaine, tetracaine, lignocaine and procaine; 0.02-2 mM) inhibited carbachol-induced catecholamine release from the cells in a concentration-dependent manner. This inhibition was completely reversible. IC50 (concentration of 50% inhibition) of each anaesthetic showed no correlation with the lipid solubility. The local anaesthetics showed greater inhibitory potency at a higher extracellular pH. The results suggest that clinically relevant concentrations of local anaesthetics inhibit the stimulus-secretion coupling in the chromaffin cells. The un-ionized based form plays a major role, and the inhibitory potency does not depend on the lipid solubility of the anaesthetics.
Adrenal Medulla↗
In vitro anti-human immunodeficiency virus (HIV) activities of transition state mimetic HIV protease inhibitors containing allophenylnorstatine.
Transition state mimetic tripeptide human immunodeficiency virus (HIV) protease inhibitors containing allophenylnorstatine [(2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid] were synthesized and tested for activity against HIV in vitro. Two compounds, KNI-227 and KNI-272, which were highly potent against HIV protease with little inhibition of other aspartic proteases, showed the most potent activity against the infectivity and cytopathic effect of a wide spectrum of HIV strains. As tested in target CD4+ ATH8 cells, the 50% inhibitory concentrations of KNI-227 against HIV type 1 LAI (HIV-1LAI), HIV-1RF, HIV-1MN, and HIV-2ROD were 0.1, 0.02, 0.03, and 0.1 microM, respectively, while those of KNI-272 were 0.1, 0.02, 0.04, and 0.1 microM, respectively. Both agents completely blocked the replication of 3'-azido-2',3'-dideoxythymidine-sensitive and -insensitive clinical HIV-1 isolates at 0.08 microM as tested in target phytohemagglutinin-activated peripheral blood mononuclear cells. The ratios of 50% cytotoxic concentrations to 50% inhibitory concentrations for KNI-227 and KNI-272 were approximately 2,500 and > 4,000, respectively, as assessed in peripheral blood mononuclear cells. Both compounds blocked the posttranslational cleavage of the p55 precursor protein to generate the mature p24 Gag protein in stably HIV-1-infected cells. The n-octanol-water partition coefficients of KNI-227 and KNI-272 were high, with log Po/w values of 3.79 and 3.56, respectively. Degradation of KNI-227 and KNI-272 in the presence of pepsin (1 mg/ml, pH 2.2) at 37 degrees C for 24 h was negligible. Current data warrant further careful investigations toward possible clinical application of these two novel compounds.
Antiviral Agents↗
Analysis of the BZLF1 promoter of Epstein-Barr virus: identification of an anti-immunoglobulin response sequence.
The induction of the viral lytic cycle in latently Epstein-Barr virus (EBV)-infected B cells is initiated by activation of the BZLF1 gene, whose expression is sufficient to disrupt EBV latency, suggesting that BZLF1 acts as the switch to change from a latent to a lytic replicative cycle. In the present studies, a series of deletion plasmids encompassing positions bp -552 to +12 of the BZLF1 promoter were constructed and tested for their response to anti-immunoglobulin (anti-Ig), an inducer of the viral lytic cycle, upon transfection into EBV-negative and -positive lymphoid cells. The promoter consisted of three functionally distinct regions. Region I (bp -552 to -221) had a negative influence on promoter activity; its deletion made the promoter highly responsive to anti-Ig. Region II (bp -203 to -177) was important for conferring responsiveness to anti-Ig. The response to anti-Ig did not require the presence of the EBV genome or EBV gene products. This sequence also enhanced expression of the chloramphenicol acetyltransferase (cat) gene from the simian virus 40 promoter in response to anti-Ig, even when inserted downstream of the cat gene. Region III (-134 to -116) was a positive element that was transactivated by the BZLF1 gene product.
Antibodies, Anti-Idiotypic↗
Coordination of cortically induced rhythmic jaw and tongue movements in the rabbit.
1. Rhythmic movements of the jaw, tongue, and hyoid that were induced by stimulation of the cortical masticatory area (CMA) were recorded cineradiographically in the anesthetized rabbit. Jaw movements were also recorded by a laser position detector. 2. The evoked jaw movements were classified into four types: small circular (type A), large circular (type B), large vertical (type C), and crescent-shaped (type D). Among these, types B and D resembled the jaw movements of the food transport cycle and those of the chewing cycle in a masticatory sequence. 3. Each type of jaw movement was associated with a particular pattern of tongue and hyoid movements. In general, the tongue protruded during jaw opening and retracted during jaw closure. The hyoid generally moved upward and forward during jaw opening but downward and backward during jaw closure. 4. Electromyograms (EMGs) were recorded from jaw muscles [masseter (Ma) and digastric (Di) muscles], extrinsic tongue muscles [styloglossus (Sg) and genioglossus (Gg) muscles], and hyoid muscles [sternohyoid (Sh) and geniohyoid (Gh) muscles] during cortically induced rhythmic jaw and tongue movements (CRJTMs). These muscles were classified into two groups: group 1 was activated mainly in the jaw opening phase, and group 2 was activated mainly in the jaw closing and power phases. The Di, Gg, and Gh were included in the former, and the Ma, Sg, and Sh were included in the latter. 5. The timings of EMG activation to a jaw movement cycle were relatively constant for the muscles of group 1, irrespective of the types of CRJTMs, whereas those for the muscles of group 2 altered considerably with the different types of CRJTMs. 6. Relationships of the integrated muscle activity between the Di and Gg and between the Di and Gh were significant, whereas those between the Ma and Sg and between the Ma and Sh were not. 7. When a small strip of polyurethane form of various degrees of hardness was inserted between the opposing molars during CRJTMs, EMG activity of the muscles of group 2 increased with the hardness of the strip. On the other hand, EMG activities of the muscles of group 1 were less affected by the same intraoral stimuli. 8. Two conclusions were reached: first, physiological properties of the CRJTMs and cortically induced rhythmic movements of the hyoid were essentially similar to those observed in natural mastication. This fictive mastication might thus be regarded as a suitable model for simulating natural mastication.(ABSTRACT TRUNCATED AT 400 WORDS)
Animals↗
Changes of adenosine levels in the carotid artery, renal vein and inferior vena cava after glycerol or mercury injection in the rat.
The adenosine A1 receptor antagonist (FR113453) prevents glycerol- but not mercury-induced acute renal failure. To clarify this mechanism, adenosine concentration in the renal vein was measured serially. Plasma adenosine in the renal vein increased from the preinjection value of 120.6 +/- 15.4 (mean +/- SEM) pmol/ml to 426.9 +/- 107.5, 407.0 +/- 70.1 and 283.9 +/- 22.9 pmol/ml at 1, 5 and 60 min after intramuscular injection of 10 mg/kg of 50% glycerol into Sprague-Dawley rats. On the other hand, intramuscular vehicle (0.9% NaCl) injection and subcutaneous administration of 10 mg/kg of HgCl2 did not change or caused mild elevation of adenosine concentration in the renal vein. Furthermore, simultaneous blood collection from the carotid artery, renal vein and inferior vena cava revealed a greater increase in adenosine concentration in the inferior vena cava than in the artery or renal vein. These findings were not affected by the administration of FR113453 or vehicle (methylcellulose). The increase in adenosine in the inferior vena cava was derived from the release from the acutely damaged muscles due to glycerol injection. These findings suggest that the effect of adenosine A1 antagonist to prevent glycerol-induced acute renal failure is due to the inhibition of adenosine A1 receptor in the kidneys during the release of adenosine through the inferior vena cava. Therefore, the release of adenosine from the muscle and hemolysis plays an important role to induce acute renal failure in the glycerol-injected rat.
Acute Kidney Injury↗
Progressive encephalopathy associated with cytomegalovirus infection without immune deficiency.
Slowly progressive encephalopathy caused by cytomegalovirus is an unusual disorder, and its pathogenesis remains unknown except for cases associated with the acquired immune deficiency syndrome and organ transplantation. We report a case who showed clinical features of progressive encephalopathy. Cytomegalovirus was repeatedly isolated from urine, and cytomegalovirus-infected cells were detected in bone marrow. Serial computed tomographic head scan revealed periventricular calcification and its progression to the thalamus, cerebellum, and brain stem. On autopsy, there were multiple calcifications and diffuse glial proliferation in the gray and white matter. Perivascular inflammation was only minimal. There was no evidence of immune deficiency. This case suggests that progressive encephalopathy can be caused by cytomegalovirus infection without immune deficiency. This type of cytomegalovirus infection may be unusual, but its serious outcome should remind us to detect it accurately.
Brain↗
Growth hormone-producing pituitary adenomas: correlations between clinical characteristics and morphology.
In this study, we compared the clinical and endocrinological characteristics, neuroimaging findings, surgical outcome, and conventional histological findings (including immunohistochemistry) with the electron microscopic appearance of 31 growth hormone (GH)-producing adenomas. By electron microscopy, these 31 tumors were divided into 23 densely granulated somatotroph adenomas (DG adenomas) and 8 sparsely granulated somatotroph adenomas (SG adenomas). SG adenomas more frequently affected younger women, but no significant correlation was found between the adenoma type and the characteristic signs and symptoms of acromegaly, the incidence of diabetes mellitus or hypertension, or the basal serum GH and insulin-like growth factor I levels. A distinct response of GH to thyrotropin-releasing hormone, bromocriptine, or GH-releasing hormone was significantly more common in patients with DG adenomas than in those with SG adenomas, whereas the incidence of a response to gonadotropin-releasing hormone or oral glucose was not significantly different between the two groups. An analysis of neuroimaging findings and surgical results indicated that SG adenomas were more likely to be macroadenomas with suprasellar extension or invasive tumors and had a lower surgical cure rate. However, postoperative radiotherapy seemed to be similarly effective in both types of adenoma to prevent a tumor recurrence and to reduce postoperative GH basal level in serum. Light microscopy showed that DG adenomas were mainly acidophilic and were immunopositive not only for GH but also for prolactin (43%), the beta subunit of thyroid-stimulating hormone (26%), and the alpha subunit of glycoprotein hormone (87%), whereas SG adenomas were almost all chromophobic and only revealed immunopositivity for GH.(ABSTRACT TRUNCATED AT 250 WORDS)
Adenoma↗
Characterization of two novel polysaccharides having immunological activities from the root of Panax ginseng.
Two acidic polysaccharides, called ginsenan S-IA and ginsenan S-IIA, were isolated from the root of Panax ginseng C. A. Meyer. They were homogeneous on electrophoresis and gel chromatography, and their molecular masses were estimated to be 5.6 x 10(4) and 1.0 x 10(5), respectively. Ginsenan S-IA is composed of L-arabinose: D-galactose: D-galacturonic acid in the molar ratio of 8:8:1, and ginsenan S-IIA is composed of L-arabinose: D-galactose: D-glucose: D-galacturonic acid in the molar ratio of 15:10:2:5, in addition to small amounts of O-acetyl groups. About a half (ginsenan S-IA) and about a quarter (ginsenan S-IIA) of the hexuronic acid residues exist as methyl esters. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and periodate oxidation studies indicated that their structural features include mainly alpha-1,5-linked L-arabino-beta-3,6-branched D-galactan type structural units. Both polysaccharides showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test and pronounced anti-complementary activity. These substances are the first examples having a relatively high content of both alpha-3,5-branched L-arabinose and beta-1,4-linked D-galactose units among the acidic arabinogalactans with activities on phagocytosis and anti-complement.
Arabinose↗
Characterization of two acidic polysaccharides having immunological activities from the root of Panax ginseng.
Two acidic polysaccharides, named ginsenan PA and ginsenan PB, were isolated from the root of Panax ginseng C. A. Meyer. They were homogeneous on electrophoresis and gel chromatography, and their molecular masses were estimated to be 1.6 x 10(5) and 5.5 x 10(4), respectively. They are composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid: D-glucuronic acid in the molar ratios of 11:22:1:6:1 (ginsenan PA) and 3:7:2:8:1 (ginsenan PB), in addition to small amounts of O-acetyl groups. Almost all (ginsenan PA) and part (ginsenan PB) of the hexuronic acid residues exist as methyl esters. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and periodate oxidation studies indicated that their structural features include mainly both alpha-arabino-beta-3,6-galactan type and rhamnogalacturonan type structural units. Both polysaccharides showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test, pronounced anti-complementary activity and alkaline phosphatase-inducing activity in a dose dependent manner.
Animals↗
Arabinogalactan core structure and immunological activities of ukonan C, an acidic polysaccharide from the rhizome of Curcuma longa.
Controlled Smith degradation of ukonan C, a phagocytosis-activating polysaccharide isolated from the rhizome of Curcuma longa L., was performed. The reticuloendothelial system-potentiating, anti-complementary and alkaline phosphatase-inducing activities of ukonan C and its degradation products were investigated. Methylation analyses of the primary and secondary Smith degradation products and of a de-arabinosylated product indicated that structural features of the arabinogalactan core of ukonan C include a backbone chain composed of beta-1,3-linked D-galactose and beta-1,4-linked D-xylose. All of the galactose units in the backbone carry side chains composed of beta-1,6-linked D-galactosyl residues with or without terminal alpha-L-arabinose units at position 3. Ukonan C showed remarkable effects on both reticuloendothelial system-potentiating and alkaline phosphatase-inducing activities. Periodate oxidation caused a decrease in or disappearance of the immunological activities, but the controlled Smith degradation product having the arabinogalactan core structure of polysaccharide showed a pronounced effect on anti-complementary activity.
Adult↗
Plant mucilages. XLIII. A representative mucilage with biological activity from the leaves of Hibiscus rosa-sinensis.
A representative mucilage, called Hibiscus-mucilage RL, was isolated from the leaves of Hibiscus rosa-sinensis L. It was homogeneous on electrophoresis, and its molecular mass was estimated to be roughly 1.0 x 10(7). Its intrinsic viscosity value in aqueous solution was 23.2. The major constituent is an acidic polysaccharide composed of L-rhamnose: D-galactose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 5:8:3:2. Methylation analysis, partial hydrolysis and nuclear magnetic resonance studies indicated its main structural features including a unique backbone chain composed of alpha-1,4-linked D-galactosyl alpha-1,2-linked L-rhamnosyl alpha-1,4-linked D-galacturonic acid units. The mucilage showed considerable anti-complementary activity.
Alkaline Phosphatase↗
Involvement of brain serotonergic function in lidocaine-induced convulsions in mice.
Influences of drug-induced manipulations of central serotonergic function on lidocaine- and pentylenetetrazol (PTZ)-induced convulsions were examined in mice. Agents that suppressed serotonergic transmission increased, whereas drugs that facilitated serotonin (5-HT) function decreased the incidence of lidocaine-induced convulsions. These treatments had similar influences on the incidence of PTZ-induced convulsions. Lidocaine (10(-5)-10(-3) M) reduced the stimulation evoked [3H]5-HT release from cortical slices, followed with an increased spontaneous [3H] overflow at higher concentrations. These results may suggest that brain 5-HT neurons are causally involved as inhibitory neurons in lidocaine-induced convulsions as in the case of PTZ-induced convulsions.
5-Hydroxytryptophan↗
A case of postpartum hypopituitarism associated with empty sella: possible relation to postpartum autoimmune hypophysitis.
A fifty-year-old woman was admitted to our hospital because of generalized edema, progressive symptoms of fatigue and weakness of ten years' duration. After an uneventful third delivery, 24 years before admission, she could not lactate and developed oligomenorrhea and then amenorrhea. Laboratory evaluation revealed panhypopituitarism and pituitary cell antibodies were positive. Both CT scans and MR images showed empty sella. This case is postpartum hypopituitarism without a preceding history of excessive bleeding and may be autoimmune hypophysitis.
Autoimmune Diseases↗
High Epstein-Barr virus (EBV) susceptibility of both lymphoblastoid and lymphoma cell lines derived from a Japanese patient with EBV genome-positive Burkitt's lymphoma.
A Lymphoma cell line from the tumor tissue was established spontaneously from a Japanese patient with Epstein-Barr virus (EBV) genome-positive Burkitt's lymphoma (BL). Additionally lymphoblastoid cell lines from peripheral blood of this patient were established either spontaneously or by in vitro infection with B95-8 EBV. Lymphoma cells showed monoclonal surface immunoglobulins (kappa and gamma) with specific chromosomal translocations, t (8; 14). In contrast, lymphoblastoid cells expressed polyclonal surface immunoglobulins without specific chromosomal abnormalities. Lymphoma cells made colonies in soft agarose approximately 10 times more than those of the lymphoblastoid cells. When each cell line was cultured at lower temperature of 33 degrees C, treated with 12-O-tetradecanoyl- phorbol-13-acetate (TPA), and superinfected with P3HR-1 EBV, all cell lines expressed 5 to 10 times higher levels of EBV early antigens (EA) and viral capsid antigen (VCA) than lymphoblastoid cell lines from healthy controls. Furthermore, lymphoblastoid cell lines obtained from peripheral blood of this patient during the period of remission also exhibited high EA and VCA inducibility and superinfectibility. These findings suggested that the lymphoid cells in this patient were genetically highly susceptible to EBV infection, and this evidence possibly linked to the lymphomagenesis of EBV genome-positive BL.
Antibodies, Viral↗