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Biomedical subjects

T Satoh

Publications and source records attributed to T Satoh.

At least 829 records · Page 46Linked to original sources

Periodic abnormal fluctuations of blood pressure, heart rate and skin blood flow appearing in a resuscitated comatose patient.

Fluctuations with a period of several tens of seconds, so called third-order waves, were recognized in the blood pressure, heart rate and Laser Doppler skin blood flow of a comatose patient following cardiac arrest and resuscitation. The waves fluctuated with an abnormally high amplitude and were apparently synchronous with each other. These abnormal fluctuations appeared continuously over 6 h on the day of resuscitation, while their periodicity gradually lengthened. The patient remained in a comatose state for the next 4 days. During that period, functional signs of the sympathetic nervous system, such as peripheral vasomotion and perspiration, were also absent. However, on the 6th post-resuscitation day, when the patient exhibited signs of restoring consciousness, he also regained some sympathetic function. This patient subsequently recovered full consciousness, although abnormalities of intelligence and motor function remained to some extent.

Aged↗

Effects of forced shaking stress at low temperature on pentobarbital-induced sleeping in mice.

1. Effects of a new stressful manipulation, forced shaking stress at low temperature (4 degrees C) (FSLT stress), on sleeping induced by pentobarbital were investigated 70 min following its application. 2. Repeated application (7 times) decreased the duration of sleep induced by pentobarbital-Na (45 mg/kg, i.p.) in mice without affecting that induced by ketamine-HCl and chloral hydrate. This effect of FSLT stress disappeared 3 days after termination of application. 3. The latency of nociceptive response in hot-plate test increased in a naloxone-sensitive manner by single and repeated FSLT stress when tested immediately (2 min) after but not 70 min after the last stress application. 4. Diazepam (0.3 mg/kg, i.p.) significantly prolonged the duration of sleep induced by pentobarbital (45 mg/kg, i.p.) in stressed animals without changing that in unstressed animals. The effect of diazepam was blocked by Ro 15-1788 (10 mg/kg, i.p.), a specific benzodiazepine receptor antagonist. 5. Repeated FSLT stress thus appears to decrease pentobarbital sleep by inducing functional changes in the central nervous system and the GABAergic system may partially participate in FSLT stress-induced decrease in pentobarbital sleep.

Animals↗

3-O-alkylascorbic acids as free-radical quenchers: synthesis and inhibitory effect on lipid peroxidation.

A novel series of 3-O-alkylascorbic acids (3-RASA, 3a-n) was synthesized to act as radical scavengers for active oxygen species and free radicals, and their redox potentials and inhibitory effects on lipid peroxidation in rat liver microsomes were evaluated. The redox potentials of the 3-RASA compounds were increased by the substituent group to 90-190 mV above the potential for ascorbic acid (i.e., 3-RASA compounds were harder to oxidize). Although 3-O-dodecylascorbic acid (3c) and 3-O-(decylcarbomethyl)ascorbic acid (3i) differed in their redox potentials, they both markedly inhibited lipid peroxidation in rat liver microsomes to a similar extent (IC50 = 3.1 and 3.3 X 10(-6) M, respectively). Structure-activity relationship studies demonstrated that the anti lipid peroxidation activity of the 3-RASA compounds was markedly dependent upon their hydrophobicity.

Animals↗

Use of fluorescent electronic endoscopy in the evaluation of peptic ulcers.

Serial changes in the color tone of the mucosa after fluorescein administration in patients with peptic ulcers were evaluated using an electronic endoscope. In the healing and scar (S1) stage of a peptic ulcer, more intense fluorescence was observed in the lesion than in the surrounding normal mucosa shortly after intravenous injection of fluorescein. On processing of the electronic endoscopic fluorescent images using HSI transformation the difference between the lesion and normal areas could be clearly identified. This difference in the fluorescent image between the lesion and the surrounding normal mucosa may be associated with changes in the mucosal blood flow and cellular functions in the lesion. Fluorescent electronic endoscopy with fluorescein thus seems to be a useful technique for examination of the gastrointestinal mucosa.

Endoscopy, Gastrointestinal↗

A specific glutathione S-transferase isozyme occurring in hereditary hyperbilirubinuria rats.

A glutathione S-transferase isozyme which is absent in normal rat liver has been isolated from the hereditary hyperbilirubinuria rat liver cytosol. The enzyme was purified to apparent homogeneity by GSH-affinity chromatography and HPLC on CM-Sepharose CL-6B. It is a heterodimer of two non-identical subunits, i.e., subunit 2 and a previously uncharacterized subunit referred to here as subunit Yx. Immunoblot analysis indicated that GST 2-Yx belongs to the alpha class. GST 2-Yx is characterized by its 4-fold higher activity towards 4-hydroxy-non-2-enal, compared to that of GST 2-2.

Animals↗

A tubule cell line established from transgenic mice harboring temperature-sensitive simian virus 40 large T-antigen gene.

Immortalization of cell lines with specific functions is important for examination of organ-specific functions in vitro. We established a kidney tubule cell line (TKC2) exhibiting a specific physiological response to hormone from the primary culture of kidneys of adult transgenic mice harboring temperature-sensitive SV40 large T-antigen gene. TKC2 cells showed temperature-sensitive growth in culture and exhibited characters of distal tubule cells such as dome formation at confluent culture and stimulation of cAMP synthesis by arginine vasopressin. These phenotypes are maintained after long passages in culture and may provide a new experimental system for studying renal physiology.

Animals↗

Changes in carboxylesterase isoenzymes of rat liver microsomes during hepatocarcinogenesis.

Among the three major carboxylesterase isoenzymes, RH1, RL1 and RL2, present in microsomes from normal rat liver, RL2 shows hydrolyzing activity towards 12-O-tetradecanoylphorbol-13-acetate and 1-oleoy1-2-acetyl-rac-glycerol, both activators of protein kinase C. Since protein kinase C has been suggested to be involved in carcinogenesis and cell proliferation, alterations in hepatic microsomal carboxylesterase isoenzymes including RL2 were studied during hepatocarcinogenesis induced by the Solt-Farber model. Alteration of RL2 was determined by measuring acetanilide-hydrolyzing activity, by quantifying the protein amount using the single radial immunodiffusion method, and by activity staining following electrophoresis of liver microsomes. The isoenzyme composition of hepatic microsomal carboxylesterase was changed after partial hepatectomy, and marked decreases in RL2 activity and protein content were observed at 4 weeks, at the time of preneoplastic foci induction. Partial hepatectomy alone also resulted in decreased RL2 activity. These findings suggest that RL2 may be involved in regulation of protein kinase C activity by metabolizing its activators at an early stage of hepatocarcinogenesis in rats.

Animals↗

Immunohistochemical observation of recovery of the periarteriolar lymphoid sheath, lymph follicle and marginal zone in the 60Co-irradiated spleen of rats.

After 60Co irradiation of rat spleen, the most severe damage was found initially in the lymph follicles (LFs); lymphocytes were decreased in number in the periarteriolar lymphoid sheath (PALS), and almost completely depleted in the marginal zone (MZ). Recovery was observed first in the PALS, followed by the LFs, and finally the MZ. From the results of immunohistochemistry, the process of recovery was assumed to involve migration of T and B lymphocytes along the arterioles from the area surrounding the terminal arteriole at the end of the PALS into the central part of the PALS and into the LF. Peripheral blood IgM+, IgD- B lymphocytes, known to be MZ precursor cells, flowed from the follicular artery to settle in the MZ. Furthermore, recovery of the PALS prior to the LFs was suggested to be essential for lymphocyte migration to the LFs.

Animals↗

Effect of intravenous gamma-globulin on neutrophil function in Kawasaki disease.

The effect of intravenous gamma-globulin (IVGG) on the neutrophil count and neutrophil chemiluminescence (CL) of patients with Kawasaki Disease (KD) was investigated. Forty patients with KD were enrolled in the study. Ten patients were treated with 100 mg/kg/day of gamma-globulin for five days (GG 100 group) and 14 patients were treated with 400 mg/kg/day of gamma-globulin (GG 400 group) for five days. These patients also took aspirin. Sixteen patients were treated with aspirin alone (ASA group). The neutrophil counts were significantly lower in the GG 400 and GG 100 groups than in the ASA group, three days, and one and two weeks after the start of treatment. Neutrophil CL of the GG 400 and GG 100 groups was significantly lower than in the ASA group one and two weeks after the start of treatment. In the in vitro study, gamma-globulin had a dose-dependent suppressive effect on the neutrophil CL in the early stage. Albumin had similar effects. The suppressive effect of gamma-globulin on CL was not specific. These findings suggest that IVGG is effective in reducing the production of active oxygen which is considered responsible for the vascular damage in the early stage of KD.

Child, Preschool↗

[A study of secretory IgA antibody titers for Chlamydia trachomatis in prostatic secretion of chronic prostatitis].

In order to study the correlation between chronic prostatitis and C. trachomatis, IgA and IgG antibody titers for C. trachomatis were measured in serum and prostatic secretion of cases of chronic prostatitis. IgA antibody titers have higher tendency in prostatic secretion than in serum. The other side, IgG antibody titers have higher tendency in serum than in prostatic secretion. This result suggested IgA antigen was reacted in local immunological response in prostatic gland. Subsequently, in order to confirm that IgA antibody in prostatic secretion is formed from secretory IgA antibody mainly, IgA antibody titers were compared with secretory IgA antibody titers. That results was considered that many cases with high IgA titers had high secretory IgA titers. The fact suggested in cases of C. trachomatis prostatitis, IgA antibody was mainly formed from secretory IgA antibody in prostatic secretion.

Chlamydia Infections↗

[Study on Chlamydia trachomatis antigen detection by an EIA kit using a monoclonal antibody--comparison with a polyclonal EIA kit in urogenital infections].

We evaluated the clinical usefulness of a new EIA kit using a monoclonal antibody, IDEIA CHLAMYDIA (IDEIA, Novo Nordisk), for detection of C. trachomatis antigen from the genital tracts of male and female cases. The results were compared with those by Chlamydiazyme (Abbott). 1. C. trachomatis antigen detection by the IDEIA and Chlamydiazyme tests before treatment; IDEIA has a significantly higher detection rate (38.0%, 105/276) than Chlamydiazyme (29.8%, 80/276), for C. trachomatis antigen from urethral smears of 276 male patients with urethritis. In 646 female cases, including cervicitis and so on, IDEIA detected C. trachomatis antigen from cervical smears in 14.5% (94/648) of the total, while Chlamydiazyme did so in 11.9% (77/648). When considering the different results using IDEIA and Chlamydiazyme, approximately 20% of the IDEIA-positive cases were Chlamydiazyme-negative. However, when IDEIA was negative, less than 1% showed Chlamydia-positive. 2. C. trachomatis antigen detection during and after treatment; We studied the clinical courses of 14 male urethritis and 8 female cervicitis cases who had had positive results with both IDEIA and Chlamydiazyme before treatment. Two of the 14 urethritis cases showed positive results with IDEIA, but not with Chlamydiazyme after either 7 or 14 days treatment by an antimicrobial agent. These two also had symptoms indicating persistent urethritis. One of the 8 female cervicitis cases showed a positive result with IDEIA but not with Chlamydiazyme after 7 days treatment by an antimicrobial agent, and this case also had symptoms indicating persistent cervicitis. Thus, these clinical findings suggest that IDEIA can detect even a small quantity of antigen soon after treatment, but Chlamydiazyme can not. In conclusion, IDEIA has a higher sensitivity than Chlamydiazyme, in the detection of C. trachomatis antigen, suggesting that IDEIA is more useful.

Adolescent↗

Molybdenum requirement for translocation of dimethyl sulfoxide reductase to the periplasmic space in a photodenitrifier, Rhodobacter sphaeroides f. sp. denitrificans.

Translocation of dimethyl sulfoxide (DMSO) reductase to the periplasmic space was studied in vivo with a photodenitrifier, Rhodobacter sphaeroides f. sp. denitrificans, using immunoblotting analysis and radioactive labeling. A polypeptide with an apparent molecular mass about 2,000 Da higher than that of DMSO reductase accumulated during induction of the reductase with DMSO. An uncoupler, carbonyl cyanide-m-chlorophenylhydrazone, inhibited the processing of the polypeptide after cells had been radioactively pulse-labeled with [35S]methionine. These results indicated that the higher-molecular-mass polypeptide was the precursor form of DMSO reductase. The precursor form accumulated in either the cytoplasm or the membrane, whereas the mature form accumulated in the periplasmic space. The membrane-bound precursor was sensitive to proteinase K treatment from both the cytoplasmic and periplasmic sides of the membrane, indicating that the polypeptide binds to the membrane, exposing it to both the outer and inner surfaces of the cytoplasmic membrane. Processing of the precursor was hampered by removal of molybdate from the medium and was restored by its readdition. It was also inhibited by the addition of tungstate in the medium.

Biological Transport↗

Exocytosis in pheochromocytoma cells after exposure to a high concentration of potassium.

An electron-microscopic study revealed exocytosis of electron-dense granules in rat pheochromocytoma (PC12) cells after 1-min exposure to a high concentration of potassium medium. Numerous omega profiles indicative of the exocytosis were seen in the surface membrane of the PC12 cells. Most omega profiles showed clear or did not contain the granule contents. Sometimes, the granular, flocculent or dense materials were seen within the omega profiles that were exposed directly to the extracellular medium. Moreover, noncoated or coated omega profiles were observed. Coated vesicles were also visible under the surface membrane. The present study suggests that PC12 cells retain the exocytotic release mechanism for catecholamines.

Animals↗

Endothelial cells create a hematopoietic inductive microenvironment preferential to erythropoiesis in the mouse spleen.

The spleen is an erythropoietic organ in mouse. To reconstruct a microenvironment essential for erythropoiesis in vitro, the stroma (MSS31) cell line had been established from a newborn mouse spleens. MSS31 cells exhibited properties of endothelial cells: (a) the cells showed the activity to uptake acetylated low-density lipoprotein (Ac-LDL) and (b) the cells can form a capillarylike structure by a phenotypic modulation in collagen matrices. MSS31 cells selectively supported the proliferation and differentiation of the erythroid progenitor cells by direct cell-to-cell contact in a semisolid medium in the presence of erythropoietin. These layers also supported erythrocyte maturation and enucleation of erythroblasts. This suggests that spleen endothelial cells are a new type of stromal cell with erythropoietic stimulation activity and may have a critical function in the hemopoietic inductive microenvironment of the mouse spleen.

Animals↗

Inhibitory effects of non-steroidal anti-inflammatory drugs on superoxide generation.

Effects of non-steroidal anti-inflammatory drugs (NSAID: amfenac sodium, diclofenac sodium, indomethacin and ketoprofen) on the generation of superoxide anion (O2-) by isolated rat polymorphonuclear leukocytes (PMN) were studied spectrophotometrically using cytochrome c. The effects of these drugs were also studied on O2- production by the xanthine-xanthine oxidase and reduced nicotinamide adenine dinucleotide phosphate (NADPH)-NADPH oxidase systems. Amfenac sodium, at 0.1 mM, inhibited significantly O2- generation in rat PMN induced by opsonized zymosan. At 0.5 mM, diclofenac sodium and indomethacin inhibited the O2- generation in rat PMN. All of the above drugs slightly inhibited O2- production by the xanthine-xanthine oxidase system. On the other hand, O2- production by the NADPH-NADPH oxidase system was significantly inhibited by the addition of amfenac sodium, ketoprofen or indomethacin. These results suggest that non-steroidal anti-inflammatory drugs do not work as an O2- scavenger and block O2- production by the NADPH-NADPH oxidase system of rat PMN. It is concluded that amfenac sodium and the other drugs are able to inhibit granulocyte O2- production by blocking the activation of NADPH-oxidase.

Animals↗