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Biomedical subjects

T Tanigawa

Publications and source records attributed to T Tanigawa.

At least 127 records · Page 7Linked to original sources
PubMed1993

Induction of unresponsiveness in rats after either intraportal injection of donor antigen or intravenous injection combined with splenectomy.

Recently, we reported that hepatic allografts are permanently accepted when transplanted after intraportal injection (IP) of donor spleen cells (SPCs). The mechanism of this effect was investigated using various protocols for antigen injection. ACI (RT1a) and Buffalo (RT1b) rats were used as donors and recipients, respectively. Experimental groups were divided into the following groups depending on treatment: IP, intravenous injection (IV), splenectomy (Spx), and intravenous injection after splenectomy (IV+Spx). Accumulation of donor antigen in the various organs was examined by injecting 51Cr-labeled SPCs. Cellular and humoral responses after SPC injection was assessed by delayed-type hypersensitivity response and complement-dependent cytotoxicity (CDC) assay. Heterotopic cardiac transplantation and orthotopic hepatic transplantation were performed 10 days after each treatment. The accumulation ratio in the liver was significantly higher in the IP and IV+Spx groups than in the IV group. Delayed-type hypersensitivity responses were lower in the IP and IV+Spx groups than in the IV or Spx groups. The CDC titer 7 days after inoculation was significantly lower in the IP and IV+Spx groups than in the IV group. In order to examine whether the treatment actively suppressed the immune response, the animals were rechallenged with SPCs given intravenously 10 days after the initial injection. Elevation of CDC titer was suppressed in the IP and IV+Spx groups, but not in the IV and Spx groups. Significant prolongation of cardiac allograft survival was not observed in the IV and Spx groups. Prolongation was observed in the IP and IV+Spx groups. The survival of hepatic allografts in the IV group was decreased. No significant prolongation of graft survival was observed in the Spx group. In contrast, all hepatic allotransplants in the IP and IV+Spx groups survived over 45 days. These findings suggest that the accumulation of donor SPCs in the liver may play an important role in inducing unresponsiveness after intraportal injection of donor SPCs.

Animals↗
PubMed1993

Effects of thiols on prostaglandin synthesis in bovine bladder epithelium.

The regulation of prostaglandin (PG) synthesis was characterized in microsomes of bovine bladder epithelium. Coenzyme A (CoA) and its metabolite cysteamine drastically decreased total PG synthesis. Furthermore, CoA inhibited solubilized cyclooxygenase which was precipitated by anti-cyclooxygenase antibody. Reduced glutathione (GSH) slightly increased total PG production and changed the pattern of PG synthesis. Other thiols, cysteine and ergothioneine, did not change total PG production. None of the thiols stimulated the incorporation of arachidonic acid into the phospholipid fraction. These findings suggest that CoA may directly regulate cyclooxygenase activity and GSH may subsequently change the pattern of PG production in bovine bladder epithelium.

6-Ketoprostaglandin F1 alpha↗
PubMed1993

Changes of rat urinary bladder during acute phase of spinal cord injury.

Spinal cord injury (SCI) at Th13 was induced in female Wistar rats, and changes in the urinary bladder were examined during the acute phase of SCI. Wet weights of the spinal bladders increased twofold over controls by 7 days after SCI. Intravesical volumes increased sixfold over control values by day 3, and then decreased 7 days after the injury. Maximal pressure within the bladder decreased in all spinal rats compared with controls. Smooth muscle cells were isolated from the urinary bladder, and their total protein and DNA content were measured by multiparametric cytofluorometry. DNA content of isolated smooth muscle cells decreased by day 3 and remained 7 days after the spinal injury. Total protein content of isolated smooth muscle cells was decreased 1 day after and increased 7 days after the spinal injury, just when spinal reflex of the bladder recovered. These findings suggest that hypertrophy of smooth muscle cells in urinary bladder is related to the activity of peripheral autonomic nerve and that smooth muscle cells already begin to hypertrophy during the spinal shock period to adjust themselves to the new state, that is, the spinal bladder.

Acute Disease↗
PubMed1993

Polymeric N-acetyl-D-glucosamine (chitin) induces histionic activation in dogs.

Analyses on the effects of polymeric N-acetyl-D-glucosamine (chitin), which was obtained from squid pen, on histiogenic activation in dogs were carried out with subcutaneous implants (5 x 5 cm2) of polyester non-woven fabric (NWF) supplemented with chitin (chitin group) and NWF (control group). These materials were implanted at 4 sites, on the lumbodorsal and lumbosacral subcutaneous tissues on both sides of the midline in each dog under general anesthesia. The implants and their surrounding tissues were isolated on post-implantation days (PIDs) 2, 4, 8, and 18 under general anesthesia. In the chitin group, the implant was organized gradually and its organization was completed on PID 18, when obvious angiogenesis toward the NWF was observed. On the other hand, in the control group, obvious angiogenesis toward the NWF was not observed macroscopically. Numbers of mononuclear (MN) and polymorphonuclear (PMN) cells concentrated around the implants on PID 2 were larger in the chitin than control group. In the chitin group, formation of granulating tissue around the implant was indicated on PID 4, whereas such a phenomenon was not observed in the control group. From these results, chitin accelerates the migration of MN and PMN cells to the NWF site with rapid follow-up organization of the NWF accompanied by angiogenesis.

Animals↗
PubMed1993

Application of polymeric N-acetyl-D-glucosamine (chitin) to veterinary practice.

The sponge-, cotton-, and flake-type remedies made of chitin (chitin-sponge, chitin-cotton, and chitin-flake, respectively), and non-woven fabric of polyester (NWF) composited with chitin (chitin-NWF) were applied to various types of trauma, abscess, surgical tissue defect and herniorrhaphy in 147 clinical cases including 72 dogs, 38 cows, 33 cats, 2 rabbits, one monkey and one horse. Chitin-sponge was applied in 30 cases as filling agent of surgical tissue defect, and in 25 cases of trauma, 31 cases of abscess as wound dressing or tissue defect filling agent. In 77 out of 86 cases (89.5%), good healing developed. When chitin-sponge was buried in surgical tissue defects due to oncotomy in 20 cases, recurrence of the tumor developed in one case on one month post-operatively, but was not recognized for 3-24 months in 19 cases. Chitin-NWF was applied in 2 cases of trauma and 12 cases of abscess as wound dressing or tissue defect filling agent, 6 cases as filling agent of surgical tissue defect, and 12 cases of umbilical hernia as prosthesis of suture site of hernia ring. In 28 out of 32 cases (87.5%), good healing developed. Chitin-cotton was applied in 8 cases of trauma and 12 cases of abscess as wound dressing or tissue defect filling agent. In 18 out of 20 cases (90.0%), good healing developed. Chitin-flake was applied in 9 cases of trauma as wound dressing or tissue defect filling agent. In 8 out of 9 cases (88.9%), good healing developed. In all cases, no side effects were observed.

Abscess↗
PubMed1993

Cardiac autonomic dysfunction in rotogravure printers exposed to toluene in relation to peripheral nerve conduction.

The autonomic nervous effects of toluene remain less clear. To clarify this neurotoxicity, ten rotogravure printers and the same number of age-matched unexposed controls were examined, by using the coefficient of variation in electrocardiographic R-R intervals (CVRR), the distribution of nerve conduction velocities (DCV) and the maximal motor and sensory nerve conduction velocities (MCV and SCV) in the median nerve. Also, the C-CVHF and C-CVLF (two component CVs of the CVRR reflecting parasympathetic and sympathetic activities, respectively) were computed from component spectral powers using autoregressive spectral and component analyses. These printers had been exposed to toluene (estimated exposure levels of toluene at 83 ppm) for 1-36 years. The CVRR and C-CVHF were significantly lower in the printers than in the controls. No significant difference between the printers and the controls was found in either any DCV parameters or the SCV in the forearm, except the MCV and the SCV in the palm. In the light of previous work on the brainstem/hippocampus damages due to toluene, these data suggest that toluene causes potential damages in the central autonomic nervous system, mainly parasympathetic hypoactivity.

Adult↗
PubMed1993

Spin trapping of superoxide from glass adherent polymorphonuclear leukocytes induced by N-formylmethionyl-leucyl-phenylalanine.

Dahinden et al. reported that N-formylmethionyl-leucyl-phenylalanine (fMLP)-induced superoxide release from polymorphonuclear leukocytes (PMNs) lasted more than 60 min when the cells were allowed to attach to a petri dish before induction. In contrast, it lasted only for 2.5 min when cells were in suspension (J. Clin. Invest. 72: 113-121, 1983). In spite of this report, the effect of cell adhesion has been ignored in most spin trapping studies of superoxide release from PMNs. This study shows that most PMNs in a quartz flat electron paramagnetic resonance (EPR) cuvette which was placed horizontally adhered to the wall within 3 min. In contrast, if the cuvette was placed vertically, only 20-30% of the cells became adherent in 30 min. We performed spin trapping studies using 5,5-dimethylpyrroline-N-oxide (DMPO) as a spin trap, and monitored the effect of cell adhesion on superoxide generation. When spin trapping was conducted on PMNs in suspension, the EPR signal of superoxide adduct (DMPO-OOH) was undetectable after stimulation with fMLP. However, PMNs which were allowed to adhere to the cuvette after stimulation generated superoxide for hours. Moreover, when PMNs were allowed to adhere prior to the stimulation, the magnitude of superoxide release was augmented three-to fourfold. Unlike fMLP, phorbol myristate acetate (PMA), which has been most commonly used in spin trapping studies, induced superoxide release which was not influenced by cell adhesion. We emphasize the importance of specifying the cell-adhesion-state in spin trapping studies.

Cell Adhesion↗
PubMed1993

Antioxidant properties of antiulcer Kampo medicines.

Kampo medicines, aqueous extracts of a mixture of natural crude drugs, have numerous ingredients. Recent pharmacologic studies on Kampo medicines have clarified their many and varied biological activities. In this study, based on recent research that has been directed toward the excellent antioxidant properties of Kampo medicines, we investigated antioxidant activities of three Kampo medicines (TJ-10, TJ-35, TJ-43), which are clinically used for gastritis or peptic ulcer, by the electron paramagnetic resonance (EPR) spin trapping method. These Kampo medicines, especially TJ-35 scavenged superoxide generated from the hypoxanthine-xanthine oxidase system, and slightly inhibited the superoxide generation from polymorphonuclear leukocytes stimulated by phorbol myristate acetate or opsonized zymosan. Three Kampo medicines, especially TJ-35 also inhibited the generation of hydroxyl radicals by the Fenton reaction. These results suggest that these antioxidant properties may be partly responsible for anti-ulcer actions of these three Kampo medicines, especially TJ-35.

Antioxidants↗
PubMed1993

Detection of free radicals in the blood of animals using extracorporeal circulation.

A method was designed to detect free radicals in circulating blood of animals using extracorporeal circulation and electron paramagnetic resonance (EPR). An arterial-venous shunt was inserted into male Wistar rats between the distal abdominal aorta and the inferior vena cava. The polyethylene tube of the shunt was flowed through a quartz EPR cell. The circulation was supported by manual pumping and maintained at a rate of 3 ml/min. No signal was detected in the blood of untreated rats. After a bolus injection of four spin labels, 2,2,6,6-tetramethyl-piperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethyl-piperidine-1-oxyl, 3-carbamoyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl, and 3-carbamoyl-2,2,5,5-tetramethyl-pyrroline-1-oxyl, signals from each were detected. The intensity of the signal decreased exponentially and the half time was 23.9, 21.6, 47.1, 42.4 sec, respectively. After administration of ascorbic acid, ascorbyl radical signals were detected. This was enhanced by ethylenediaminetetraacetic acid-Fe or diethylenetriaminepentaacetic acid-Fe but not desferrioxamine-Fe. This assay system is useful in detecting free radicals either administered or generated in vivo.

Animals↗
PubMed1993

Free radical scavenging activity of the novel anti-ulcer agent rebamipide studied by electron spin resonance.

The anti-free radical action of rebamipide (2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinon-4-yl] propionic acid, CAS 11911-87-6), a novel anti-ulcer agent, was investigated by electron spin resonance spectroscopy. A spin trapping method using 5,5-dimethyl-1-pyrroline-N-oxide showed that rebamipide dose-dependently decreased both the intensity of the hydroxyl radical spin adduct signal generated by the Fenton reaction and the intensity of the superoxide spin adduct generated from opsonized zymosan-stimulated neutrophils. A kinetic study showed that the second order rate constant for the reaction between rebamipide and hydroxyl radicals at pH 7.8 was 2.24 x 10(10) mol l-1 s-1. These results indicate in vitro antioxidant properties of rebamipide which is active as hydroxyl radical scavenger and inhibitor of superoxide production in neutrophils.

Alanine↗
PubMed1992

Establishment of an enzyme release assay for cytotoxic T lymphocyte activity.

In the present report, we describe the establishment of a cell line that can be used as the target for measuring the activity of cytotoxic T lymphocytes (CTL) by an enzyme release assay. We transfected P3/NS1-Ag4-1 (NS-1), a myeloma cell line derived from BALB/c mice with Escherichia coli beta-galactosidase (beta-Gal) gene, and isolated a stable transformant designated as NS-1/Z that expressed a high level of the enzyme activity intracellularly. The effector cells showing cytotoxicity against NS-1/Z were induced when the spleen cells of AKR or C3H mice were cultured with mitomycin C-treated BALB/c spleen cells for 4 days. When 2 x 10(4) NS-1/Z cells were incubated with varying numbers of effector cells, beta-Gal activity was released from the target cells depending on the number of effector cells and the time of incubation for up to 8 h. A highly sensitive enzyme assay was performed by using a fluorescent substrate, 4-methylumbelliferyl-beta-D-galactoside. The cytotoxicity was specific for H-2 haplotype of the stimulator cells, and was abolished by treating the effector cells with anti-Lyt 2 plus complement. The sensitivity of the enzyme release assay was comparable to that of 51Cr release assay. These results indicate that NS-1/Z can be used as a target cell line for the non-radioactive measurement of CTL activity.

Animals↗
PubMed1992

Immunocytochemical demonstration of IGF-II immunoreactivity in human phaeochromocytoma and extra-adrenal abdominal paraganglioma.

Insulin-like growth factor (IGF)-II immunoreactivity was demonstrated in 14 adrenal glands, six retroperitoneal paraganglia, 18 phaeochromocytomas, and six extra-adrenal abdominal paragangliomas through the use of a monoclonal antibody against rat IGF-II which cross-reacts with human IGF-II. A subpopulation of parenchymal cells in normal adrenal medulla and in retroperitoneal paraganglia was positively immunolabelled. Eighteen cases with phaeochromocytoma including two malignant and four multiple endocrine neoplasias all contained numerous IGF-II-immunoreactive tumour cells. All six extra-adrenal abdominal paragangliomas contained numerous immunoreactive tumour cells. Almost all the other normal human adult tissues examined failed to immunolabel. These results indicate that IGF-II-like immunoreactivity is widely expressed in normal and neoplastic human paraganglionic tissues, although its biological significance in these tissues has not been determined.

Abdominal Neoplasms↗
PubMed1992

Characterization of macrophage cell line A640-BB-2: A640-BB-2 resembles peritoneal exudate macrophages in cell morphology, tumor cell recognition, responsiveness to immunomodulator OK-432 and lysosomal enzyme activity.

Characteristics of mouse macrophage (MP) cell lines A640-BB-2, J774.1 and P388D1 and mouse peritoneal exudate MPs were studied and compared in cell morphology, ability to recognize tumor cells in the presence and absence of OK-432 known to activate MPs, and in lysosomal enzyme activity. In A640-BB-2 cells and exudate MPs, cell surfaces showed a few ridge-like processes and microvilli; spontaneous cytotoxicity was moderate against tumor target L929, and little or absent against targets SV3T3, B-16 and U937; and lysosomal enzyme activity of nonspecific esterase, acid phosphatase, and beta-glucuronidase was high. After culture in the presence of OK-432, A640-BB-2 cells and exudate MPs showed more extensive spreading with larger surface areas and with increased numbers of ridge-like processes and microvilli, and their cytotoxicity against target L929 became more extensive. The stable soluble factor did not participate in the mechanism of cytotoxicity against target L929 mediated by A640-BB-2 cells and exudate MPs. J774.1 and P388D1 cells were different from exudate MPs in cell morphology and ability to recognize tumor cells when cultured either with or without OK-432, and in lysosomal enzyme activity. A640-BB-2 cells seem to be useful in studying MP-tumor cell interaction and MP activation, and in detecting the trace biological activating factor of MPs.

Acid Phosphatase↗
PubMed1992

Effects of a platelet-activating factor antagonist, CV-6209, on gastric mucosal lesions induced by ischemia-reperfusion.

Recent research was shown that oxygen-derived free radicals are involved in the pathogenesis of various diseases, including ischemia-reperfusion injury. We have also reported that oxygen-derived free radicals and lipid peroxidation may play an important role in gastric mucosal injury induced by ischemia-reperfusion. The hypoxanthine-xanthine oxidase system and neutrophils are considered important sources of oxygen-derived free radicals in this process. In recent years, it also has been shown that serum platelet-activating factor (PAF) levels increased during ischemia-reperfusion, and that induction of superoxide generation by neutrophils is one of the important biological effects of PAF. In the present study, we examined the effect of CV-6209, a specific PAF receptor antagonist, on gastric mucosal injury induced by ischemia-reperfusion, to shed some light on the possible involvement of PAF in such lesions. CV-6209 significantly attenuated the gastric mucosal injury induced by ischemia-reperfusion, and inhibited both an increase of thiobarbituric acid reactive substances and a decrease of alpha-tocopherol in gastric mucosa after ischemia-reperfusion. However, CV-6209 had no effect on gastric mucosal blood flow during ischemia-reperfusion. These results suggest that endogenous PAF may play an important role in gastric mucosal injury induced by ischemia-reperfusion, and that CV-6209 exerts its beneficial effect mainly by inhibiting neutrophil superoxide production induced by PAF.

Animals↗
PubMed1992

Behaviour of mouse macrophage cell line and mouse fibroblast on copolymers containing cellulose triacetate.

Copolymers containing cellulose triacetate were prepared under various conditions. A bacteriological plastic dish was coated with the copolymer (HCTA-MDI copolymer) composed of hydrolysed cellulose triacetate (HCTA) and diphenylmethane diisocyanate (MDI). The deacetylated copolymer (DA-copolymer) was prepared by the deacetylation of HCTA-MDI copolymer. The behaviour of animal cells such as a mouse macrophage cell line (A640-BB-2 cells) and a mouse fibroblast (3T6 cells) on prepared dishes was investigated morphologically. A640-BB-2 cells showed good adhesion and smooth spreading, and 3T6 cells also showed good adhesion and sufficient cell growth on the dish coated with HCTA-MDI copolymer. These results suggest that these copolymers are useful for biomedical materials.

Animals↗
PubMed1992

Acute effects of alcohol on cognitive function and central nervous system assessed by auditory event-related potentials.

To clarify which sites of the central nervous system are influenced by acute administration of alcohol at an early stage, auditory event-related potentials (ERP) using a target-selection paradigm were measured in 13 healthy volunteers. In the recorded waveforms of ERPs, the N100, P165, N200 and P300 latencies for the target tone and the N100 and P200 latencies for the non-target tone were determined in each subject before and 1- and 2-hr after ingestion of 200 ml of alcohol (containing 25% ethanol) or of 200 ml of water, for a total of six times on two different days. The P300 latency was significantly prolonged at 1- and 2-hr after alcohol ingestion; and, the N200 latency was significantly prolonged at 2-hr after alcohol ingestion. The 2-hr alteration in the P300 latency after alcohol ingestion was positively correlated with the ethanol dose per body weight. These data suggest that ethanol, in proportion to its dose, affects cognitive function estimated by the P300 latency earlier than other lower central nervous system functions. Evaluating subclinical effects on central nervous function, using the ERPs, of environmental neurotoxins such as organic solvents, researchers should pay particular attention not only to the degree of the drinking habit but also to the interval between the measurement and alcohol intake.

Adult↗