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Biomedical subjects

K Oki

Publications and source records attributed to K Oki.

At least 55 records · Page 3Linked to original sources
PubMed1988

Small intestine transplantation: a logical solution for short bowel syndrome?

The purpose of this study is to determine whether small intestine transplantation could be considered as an alternative treatment in infants and children with short bowel syndrome. The potential nutritional consequence of orthotopic small intestine transplantation was evaluated in a rat model. Young Lewis strain rats (weighing 250 to 275 g) were used. Lewis rats with resection of 90% of the small intestine were studied as short bowel group (group I, n = 5). In the transplant group rats, 90% of the original small intestine was transplanted orthotopically using microvascular techniques (group II, n = 5). During the study period of 8 weeks, group II gained weight at rates equal to that of normal age matched rats (+30% of the preoperative weight), whereas rats with short bowel (group I) lost 10% of their weight. Two weeks following transplantation, serum albumin levels were maintained in the normal range in group II. However, group I rats showed decreased albumin levels. Serum cholesterol levels showed no significant difference between the two groups. Maltose absorption was evaluated as a functional test of small intestinal graft absorption (1.0 mg/g body weight of maltose was orally administered, and serum glucose levels were measured). The glucose level at 45 minutes was significantly blunted in group I in comparison with group II. The data from this study suggested that small intestine transplantation can produce adequate nutritional support to sustain growth and development in this rat model. It would be anticipated that small intestine transplantation in patients with short bowel syndrome would also benefit nutritionally.

Animals↗
PubMed1988

Isolation and characterization of rotavirus from feral pigeon in mammalian cell cultures.

Avian rotaviruses were isolated from feral pigeon faeces treated with trypsin using roller tube cultures of mammalian cells. Two pigeon strains, designated as strains PO-8 and PO-13, produced a marked cytopathic effect (CPE), small intracytoplasmic inclusion bodies and high titres of infectious particles in infected MA-104 and MDBK cell lines without cell adaptation and roller drum apparatus. The pigeon rotaviruses shared a common group specific antigen with the Lincoln strain of bovine rotavirus by indirect immunofluorescence, but differed from both the Lincoln strain and the Wa strain of human rotavirus in neutralization tests. The RNA segment profile of this virus on polyacrylamide gel electrophoresis differed from that of group A mammalian rotaviruses. The results of a serological survey suggested that antibody to pigeon rotaviruses was widespread in avian species in Japan.

Animals↗
PubMed1988

Eosinophilic leucocytes and arylsulfatase activity in bronchoalveolar lavage fluid of patients with bronchial asthma.

The arylsulfatase activity and histamine concentration of bronchoalveolar lavage fluid (BALF) were examined in patients with bronchial asthma in relation to the eosinophil count and asthma type (atopic and non-atopic). The BALF arylsulfatase activity and histamine concentration were significantly higher in atopic asthmatics than in non-atopic asthmatics. In atopic asthmatics, the activity of arylsulfatase was significantly increased in patients with a higher eosinophil count (10% or more). However, the BALF histamine concentration did not correlate with the eosinophil count. In non-atopic asthmatics, there was no significant correlation between arylsulfatase activity and the eosinophil count. The results show that arylsulfatase participates in IgE-mediated allergic reactions.

Adult↗
PubMed1987

[The Su-polysaccharide skin test in lung cancer].

Skin testing with intradermally injected Su-Polysaccharide (extracted from Su strain Streptococcus bacteria) was performed in 41 cases of lung cancer. Su-polysaccharide skin test results were correlated, to some extent, with the patient's age, clinical stage and performance status and showed a similar trend to the simultaneously performed PPD skin test. These results suggested the potential usefulness of Su-Polysaccharide skin test results as one of the parameters of immunological status of patients with lung cancer. It was also demonstrated that skin reaction to Su-Polysaccharide was increased specifically after OK-432 immunotherapy and was well correlated with the prognosis of the disease. The Su-Polysaccharide skin test was thus considered to be a useful parameter for monitoring the immune response to OK-432 immunotherapy in lung cancer and also one of the parameters of prognostic value.

Adult↗
PubMed1984

In vitro and ex vivo inhibition by flutoprazepam of [3H]flunitrazepam binding to mouse brain receptors.

The ability of flutoprazepam, a new antianxiety drug of the benzodiazepine class, to inhibit [3H]flunitrazepam binding to mouse brain receptors was investigated in vitro and ex vivo (measurement of [3H]flunitrazepam binding in vitro after in vivo treatment of animals with unlabelled drugs). The Ki values for [3H]flunitrazepam binding in vitro were as follows: flutoprazepam (13.0 nM), diazepam (2.7 nM), nitrazepam (5.3 nM), prazepam (68.5 nM) and chlordiazepoxide (234 nM). Two metabolites of flutoprazepam, N-desalkyl-flutoprazepam (Ki = 3.1 nM) also inhibited [3H]flunitrazepam binding in vitro with higher potencies than that of flutoprazepam. Flutoprazepam was found to be more active in inhibiting [3H]flunitrazepam binding ex vivo and in preventing pentetrazol convulsions than predicted from Ki values. The ID50 values for inhibiting [3H]flunitrazepam binding ex vivo were 0.32 mg/kg, p.o. (flutoprazepam), 0.89 mg/kg, p.o. (diazepam), 0.94 mg/kg, p.o. (nitrazepam), 1.98 mg/kg, p.o. (prazepam) and 23.3 mg/kg, p.o. (chlordiazepoxide), respectively. The correlation between ID50 values ex vivo and ED50 values for preventing pentetrazol convulsions was highly significant (r = 0.929). These results suggest that flutoprazepam can exert its pharmacological activities by itself and that two metabolites also play an important role in the effects of flutoprazepam in vivo.

Animals↗
PubMed1983

Striatal [3H]GTP binding in developing rats: involvement of sulfhydryl residues, Ca2+ and Mg2+.

The influence of sulfhydryl reagents and cations on specific [3H]GTP binding to striatal membranes was investigated in developing rats. Two components of non-cooperative [3H]GTP binding sites were observed in 15, 30, 70 and 360 day old rats but only a single component in 1 and 7 day old ones. The KD for low affinity binding increased with age. Bmax values for both high and low affinity binding increased with age and reached a peak at 30 days, followed by a decrease at 70 and 360 days. At 7 and 70 days, NaCl 1-100 mM did not affect [3H]GTP binding but CaCl2 and MgCl2 significantly inhibited the binding over a concentration range of 1-100 mM. TLC analysis of [3H]GTP and the metabolites in the binding medium and membranes showed that [3H]GTP in both membranes and in the medium was decreased by addition of 1 mM CaCl2 and 1 mM MgCl2 into the binding medium. On days 7 and 70, p-chloromercuriphenyl sulfonate strongly inhibited [3H]GTP binding, and dithiothreitol significantly increased binding but dopamine, apomorphine, spiperone and alpha-flupenthixol did not increase binding up to 0.1 mM. It is suggested that sulfhydryl residues, Ca2+ and Mg2+ are involved in the regulation of guanine nucleotide binding and that the regulatory mechanism becomes functional at 7 days. Ca2+ and Mg2+ seem to act by stimulating degradation of [3H]GTP. In addition, the density of GTP binding sites reaches a peak at around 30 days and the affinity decreases with age.

4-Chloromercuribenzenesulfonate↗
PubMed1983

Influence of thyrotropin-releasing hormone on general behavior and striatal [3H]spiperone binding in developing rats.

An intraperitoneal administration of thyrotropin-releasing hormone (TRH, 2 or 20 mg/kg) produced behavioral excitement and consequently an increase in ANIMEX counts 15 min after the injection in a dose-dependent manner in 70-day-old rats. On the other hand, TRH (2 or 20 mg/kg)-induced behavioral excitement appeared more slowly (90-150 min) and more persistently in 7-day-old animals than in 70-day-old animals. TRH (2 or 20 mg/kg) significantly reduced specific [3H]spiperone binding to striatal membranes in 7- and 70-day-old rats compared to control, when the binding was examined in the membranes obtained from animals sacrificed 15 min and 150 min following TRH injection. In vitro addition of TRH up to 0.1 mM did not affect [3H]spiperone binding on days 7 and 70. From these results, it is suggested that striatal dopamine receptors could be involved in TRH-induced behavioral excitement in developing rats.

Animals↗
PubMed1982

Ontogenetic development of the striatal [3H]spiperone binding: regulation by sodium and guanine nucleotide in rats.

Ontogenetic development of specific [3H]spiperone binding to crude synaptic membranes and its regulation by Na+ and GTP was investigated in the rat striatum. (d)-Butaclamol more effectively inhibited [3H]spiperone binding than (l)-butaclamol. The ratio of inhibitory activity of (d)- and (l)-butaclamol for [3H]spiperone binding was not different between 1-, 7-, and 70-day-old animals but eight- to ninefold lower at 18 days of gestation than during the postnatal period. A Scatchard plot of specific binding indicated the presence of two types of binding: low-affinity (KD = 1.51 nM) and high-affinity (KD = 0.09 nM) binding on day 70. Only one component (KD = 0.075 nM) was observed on days 1 and 7 and both types of binding were found on day 15. Bmax gradually increased with age and reached a peak on day 30, followed by a decline on days 70 and 360. Na+, 100 mM, significantly increased specific binding on days 1, 7, 15, and 70. GTP, 50 microM, completely reversed the Na+-induced decrease in IC50 of apomorphine on both days 15 and 70, but not on day 7. It is suggested that receptors could recognize ligand stereospecificity on day 1. The density in dopamine receptors in the striatum reaches a peak on day 30, followed by a decrease on days 70 and 360. In addition, regulation by Na+ and GTP in agonist binding to dopamine receptors seems to become functional between 1 and 2 weeks after birth.

Aging↗
PubMed1982

Development of inhibitory activity of sulpiride for synaptic [3H]-spiperone binding in the rat striatum.

To establish the functional development of striatal dopamine2 (DA2) receptors, the effects of NA+ and GTP on the potency of sulpiride in competing for specific [3H]-spiperone binding were investigated in the striatum of developing rats. The IC50 value of sulpiride for specific [3H]-spiperone binding was 31-fold decreased by 100 mM Na+ compared to that in 70-day-old control animals but not by 50 microM GTP. In the presence of Na+, the IC50 of sulpiride was low in fetuses at 18 days of gestation and high at 360 days of postnatal life. It is suggested that the Na+-dependent binding of sulpiride to DA2 receptors probably reaches functional maturity in fetuses at 18 days of gestation and that the Na+ dependence of the effect decreases during aging.

Aging↗
PubMed1982

Involvement of central noradrenergic system in thyrotropin-releasing hormone-induced behavioral excitement in 6-OHDOPA-treated, infant rats.

A subcutaneous (s.c.) injection of thyrotropin-releasing hormone (TRH) 20 mg/kg, produced body shake and struggle, consequently induced an increase of count in ANIMEX activity meter in 7-day-old rats pretreated with 6-hydroxydopa (6-OHDOPA), 75 mg/kg, on days 0, 2 and 4. TRH-induced behavioral excitement was markedly attenuated in the infant animals which were injected desmethylimipramine, 5 mg/kg, 30 min before 6-OHDOPA on days 0, 2 and 4. It is suggested that central catecholaminergic, in particular, noradrenergic system is involved in TRH-induced body shake and struggle in 6-OHDOPA-treated, infant rats.

Animals↗