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Biomedical subjects

J Fukuda

Publications and source records attributed to J Fukuda.

At least 37 records · Page 2Linked to original sources
PubMed2002

Evaluation of interleukin 1 as a mucosal adjuvant in immunization with Streptococcus sobrinus cells by tonsillar application in rabbits.

To evaluate interleukin 1 (IL-1) as a mucosal adjuvant in the induction of salivary antibodies to Streptococcus sobrinus, S. sobrinus together with IL-1 was applied through the palatine tonsils of rabbits. IL-1 caused approximately 50 and 100% increases in the antibodies reacting against S. sobrinus fragments in the saliva and blood plasma, respectively, compared to the antibodies in those same fluids after tonsillar applications of S. sobrinus alone. In the case of the addition of IL-1, the antibodies reacting to the protein antigens of S. sobrinus increased in each fluid, without affecting the antibodies reacting to saccharide antigens. Delayed-type hypersensitivity to S. sobrinus, characterized by ear swelling and by an increase in IFN-gamma mRNA in RT-PCR analysis, was found to be induced only in rabbits immunized with IL-1. S. sobrinus protein antigens caused ear swelling as intense as that caused by S. sobrinus fragments. Thus, IL-1 induced an antibody response and cell-mediated immunity mainly reacting to protein antigens of S. sobrinus.

Adjuvants, Immunologic↗
PubMed2002

The effects of rifampicin on the pharmacokinetics and pharmacodynamics of orally administered nilvadipine to healthy subjects.

AIMS: To study the effects of rifampicin on the pharmacokinetics and pharmacodynamics of nilvadipine. METHODS: Five healthy adult volunteers received nilvadipine (4 mg) orally before and after a 6 day treatment with rifampicin. Blood and urine were collected and assayed for plasma nilvadipine and urinary 6beta-hydroxycortisol and cortisol. RESULTS: The treatment with rifampicin reduced the mean (+/- s.d.) AUC of nilvadipine from 17.4 +/- 8.4 to 0.6 +/- 0.4 microg l-1 h (mean difference -16.8 microg l-1 h, 95% CI -9.4, 24.2 microg l-1 h). While the administration of nilvadipine alone elicited a significant (P < 0.05) hypotensive (mean difference for diastolic blood pressure -8 mmHg, 95% CI -4, -12 mmHg) and reflex tachycardia (mean difference 5 beats min-1, 95% CI 1, 9 beats min-1), the treatment with rifampicin abolished these responses. The urinary 6beta-hydroxycortisol/cortisol ratio showed a significant (P < 0.05) increase from 10.3 +/- 4.0 to 50.3 +/- 24.6 by rifampicin: mean difference 40.1, 95% CI 20.4, 59.8. CONCLUSIONS: Because rifampicin may greatly decrease the oral bioavailability of nilvadipine, caution is needed when these two drugs are to be coadministered.

Administration, Oral↗
PubMed2002

An experimental model of osteoarthrosis of the temporomandibular joint in monkeys.

The purpose of this study was to develop a model of osteoarthrosis of the temporomandibular joint in monkeys, which is remarkably similar in structure and function to that of humans. Nine juvenile monkeys, two as controls and seven as an experimental group, were used in this study. In the experimental group, the articular eminence on both sides was surgically made steeper. Two animals were killed at 1 week, four at 6 months, and one at 1 year postoperatively and the temporomandibular joints were examined macroscopically and microscopically. Typical changes of osteoarthrosis were observed in the 6-month and 1-year specimens. These comprised clustering of chondrocytes which resulted in vertical and horizontal splitting in the articular cartilage, and fibrillation of the articular surface resulting in fibrous union in the joint cavity. These degenerative changes advanced progressively over time. Slight anterior displacement and degenerative changes in the articular disc were also seen.

Animals↗
PubMed2002

Development of a hybrid artificial liver using polyurethane foam/hepatocyte spheroid culture in a preclinical pig experiment.

We describe a preclinical study of our original hybrid artificial liver support system (HALSS) for a clinical trial. We designed a HALSS comprising a multi-capillary polyurethane foam packed-bed module (MC-PUF module) containing a total 200 g (2 x 10(10) cells) porcine hepatocytes, and an extracorporeal circulation device. Almost all porcine hepatocytes in the MC-PUF module formed many spherical multicellular aggregates (spheroids). This extracorporeal circulation device was improved to promote solute exchange between a living body and a MC-PUF module by including a plasma bypass line in the circulation loop. The efficacy of the HALSS was evaluated using a 25-kg pig with warm ischemic liver failure by portocaval shunt and ligation of hepatic artery (HALSS group, n=3). As a control experiment, the same system without hepatocytes in the module was used with the same kind of liver failure pig (Control group, n=3). The blood ammonia in the control group was 143 N-microg/dl at the start of circulation, and rapidly increased to 351 N-microg/dl at 2 hours and to 704 N-microg/dl at 6 hours. But the blood ammonia in the HALSS group was completely suppressed, and remained less than the hepatic coma level (over 200 N-microg/dl) during the circulation time. The blood glucose in the control group gradually decreased, and became less than 40 mg/dl within 6 hours of circulation. But the blood glucose in the HALSS group was maintained well, and remained the normal glucose level (50 - 105 mg/dl) for more than 20 hours of circulation. Improvement in blood creatinine and lactate, and the stabilization of vital signs and urinary excretion, were observed in the HALSS group. The survival time of the pigs in the HALSS group was 19.3 hours compared with 8.9 hours in the control group. In conclusion, our HALSS was effective to stabilize the general conditions of the body in addition to supporting various liver functions. These results suggest that our HALSS has a strong possibility to be used in treating liver failure patients. We have applied for approval of the clinical trial of our HALSS to our institutional ethics committee.

Animals↗
PubMed2001

Biliary atresia with hyperandrogenic amenorrhea.

The etiology of hyperandrogenic amenorrhea in a patient with biliary atresia successfully treated by a Kasai operation was unclear. Delayed puberty and menarche were evident at 16 years of age. Investigations showed no luteinizing hormone (LH)-follicle-stimulating hormone surge. A LH-releasing hormone provocative test showed a normal response. Peripheral aromatization of androgens appeared to function normally. Free testosterone (T) was normal, however, plasma levels of sex-hormone-binding globulin and total T were high. After menarche at 18 years of age, anovulatory menstrual cycles continued. A combination of estrogen and progesterone therapy was effective. A possible explanation may be that metabolic clearance of T is reduced in the presence of liver cirrhosis and a portosystemic shunt.

Amenorrhea↗
PubMed2001

Interleukin-1beta in antigen-induced arthritis of the rabbit temporomandibular joint.

The aim was to investigate joint perfusate levels of interleukin-1beta (IL-1beta) in antigen-induced monoarthritis of the rabbit temporomandibular (TMJ) and knee joints. Twenty-four adult male New Zealand White rabbits were divided into three groups: a control group as well as TMJ arthritis and knee joint arthritis groups. After sensitization, unilateral arthritis was induced by intra-articular injection with ovalbumin and the contralateral joint was injected with saline 3 weeks after induction of arthritis. Joints were then perfused continuously with saline and samples were collected at 10-min intervals over a 50-min period. The IL-1beta concentrations in the samples were then analyzed. After killing the animals, the joints were examined histologically. The IL-1beta concentrations in the samples from the arthritic TMJs and knee joints were significantly higher than in the saline-injected and the control joints. Histological signs of chronic arthritis of similar severity were found in both joints. The IL-1beta levels in the samples from the arthritic TM and knee joints correlated with the histological severity of the arthritis, including pannus formation. In conclusion, this study shows that IL-1beta is released in the synovium of rabbit TMJs and knee joints during antigen-induced arthritis, and that high IL-1beta levels in synovial fluid are associated with histological signs of inflammation including, pannus tissue formation.

Adjuvants, Immunologic↗
PubMed2001

Detection and rapid increase of salivary antibodies to Staphylococcus lentus, an indigenous bacterium in rabbit saliva, through a single tonsillar application of bacterial cells.

In rabbits, Staphylococcus lentus is one of the major bacteria in saliva and a minor bacteria in jejunum fluids and nasal wash. The presence and induction of naturally occurring antibodies reacting to rabbit indigenous bacteria were studied. In non-immune rabbits, the proportion of anti-S. lentus IgA antibodies to total IgA in the saliva was several times higher than that in the intestinal fluids and the nasal wash. The salivary antibodies were found to have increased 1 week after a single tonsillar application of isolated S. lentus cells but not after a single nasal application or a single intragastric instillation. In addition, the anti-S. lentus antibodies in the saliva highly increased with weekly tonsillar applications of isolated S. lentus but increased only one-fifth with weekly nasal applications of the same cells. These results strongly suggest that the palatine tonsils, which we believe had already been sensitized by S. lentus in the physiological condition, induced naturally occurring antibodies in rabbit saliva.

Animals↗
PubMed2001

Synergistic effect of interleukin-1alpha and ceramide analogue on production of prostaglandin E2 and F2alpha by endometrial stromal cells.

PROBLEM: Prostaglandins (PGs) are synthesized in the endometrium. Our objective was to evaluate interleukin (IL)-1alpha-induced production of PGE2 and PGF2alpha in endometrial stromal cells (ESC) following treatment with ceramide analogues. METHODS OF STUDY: ESC were obtained from human uterine endometrium by enzymic digestion and filtration. ESC were treated with IL-1alpha, IL-1 receptor antagonist (ra), C2-ceramide and C6-ceramide. The concentrations of PGE2 and PGF2alpha in media were determined using ELISA. The induction of prostaglandin H synthase (PGHS)-2 mRNA was also ascertained by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The production of PGE2 and PGF2alpha was significantly increased by IL-lalpha and suppressed by IL-1 ra, in a dose-dependent manner. PGF2alpha production was further increased by treatment with the combination of IL-1alpha and C2-ceramide as compared with IL-1alpha treatment alone. There was no significant difference in PGE2 production between cells treated with IL-1alpha and C2-ceramide and those treated with IL-1alpha alone. Both PGE2 and PGF2alpha production were significantly increased by treatment with IL-1alpha and C6-ceramide as compared with IL-1alpha treatment alone. Treatment of ESC with IL-1alpha stimulated PGHS-2 mRNA. PGHS-2 mRNA was decreased when IL-1 ra was added to the IL-1alpha-stimulated cells. CONCLUSIONS: These results suggest that IL-1alpha stimulates the production of PGE2 and PGF2alpha by a mechanism that involves the sphingomyelin-ceramide system, and thus that ceramide may be important in increasing the production of PGE2 and PGF2alpha in the human endometrium.

Cells, Cultured↗
PubMed2001

Involvement of annexin V in the antiproliferative effect of GnRH agonist on cultured human uterine leiomyoma cells.

The objective of this study was to elucidate the role of annexin V, an endogenous inhibitor of protein kinase C (PKC), with regard to the antiproliferative effect of gonadotrophin-releasing hormone (GnRH) agonist (buserelin) on cultured human uterine leiomyoma cells. Uterine leiomyoma tissue was collected from the surgical specimens of patients and cells from 37 specimens (15 cases) were cultured. For up to 96 h after the addition of buserelin to the cultured cells, a time-dependent antiproliferative effect was noted in the group to which 10(-5) mol/l buserelin was added. Both the intracellular concentration of annexin V and the expression of annexin V mRNA increased time-dependently with the addition of buserelin. The intracellular concentration of annexin V increased with the addition of PKC activator (12-O:-tetradecanoylphorbor-13-acetate; TPA) much as it did with the addition of buserelin, and the rise in the concentration caused by the addition of buserelin was completely attenuated by pretreatment with PKC inhibitor (calphostin C). Our findings suggest that buserelin inhibits cell proliferation in cultured human uterine leiomyoma cells accompanied with an increase in the intracellular concentration of annexin V, mediated, at least in part, by the activation of PKC.

Annexin A5↗
PubMed2001

Expression of Fas and Fas ligand mRNA in rat and human preimplantation embryos.

The Fas-Fas ligand (L) system is one of the major signalling pathways to induce apoptosis in various cells and tissues. The aim of this study was to investigate the expression of the Fas-Fas L system in rat and human oocytes and preimplantation embryos. We determined the expression of Fas and Fas L mRNA of rat oocytes and embryos up to the blastocyst stage, and of human embryos at the 2- or 4-cell stage, using reverse transcription polymerase chain reaction (PCR) and nested PCR techniques. Moreover, we investigated the expression of Fas mRNA in human fragmented embryos. In rat embryos, Fas mRNA was expressed at the 2-cell stage only, whereas Fas L mRNA was expressed in oocytes, and at the pronuclear (1-cell) and 2-cell stages. In human embryos, Fas mRNA was expressed at the 4-cell stage only, whereas Fas L mRNA was expressed at both 2- and 4-cell stages. Human fragmented embryos expressed both Fas and Fas L mRNA. Because simultaneous expression of Fas and Fas L mRNA occurred in 2-cell rat embryos and in 4-cell human embryos, the Fas-Fas L system might be involved in the apoptotic pathway in the early embryos of these species.

Animals↗
PubMed2001

Identification of principal constituents in enzymatically hydrolyzed coix extract.

The structural elucidation of the main constituents in enzymatically hydrolyzed coix extract, a natural food preservative, was carried out. After peracetylation, five compounds, namely peracetylated forms of glucose, maltose, maltotriose, maltotetraose, and maltopentaose were isolated. The structures were determined by PFG HMQC and HMBC experiments. In addition, by using HPLC with an RI detector, the main components of this coix extract were identified as a mixture of oligosaccharides having one to seven glucose units coupled through alpha-(1-->4) linkages. Since this extract showed no antimicrobial activity, its preservative effect may be caused by its covering of the food surface, thereby blocking contact with air.

Carbohydrate Conformation↗
PubMed2001

The efficacy of nafamostat mesilate on the performance of a hybrid-artificial liver using a polyurethane foam/porcine hepatocyte spheroid culture system in human plasma.

Nafamostat mesilate (FUT) is a protease inhibitor of complement activation. The present study investigates whether FUT protects porcine hepatocytes from being injured by human plasma in a multi-capillary polyurethane foam packed-bed culture system (MC-PUF) such as the hybrid-artificial liver (PUF-HAL). Human plasmas with 1 mM of added ammonia were perfused using a small-scale PUF-HAL with porcine hepatocytes. FUT was continuously infused (10 microg/ml, 50 microg/ml). The ammonia detoxification was maintained in human plasma for 24 hours and for 48 hours with FUT which suppressed the rapid increase of asparaginic acid aminotransferase (AST) and alanine aminotransferase (ALT). After 60 hours of perfusion, hepatocyte spheroids completely collapsed in the human plasma, but a small amount of hepatocyte spheroid was maintained by FUT. The effect of FUT was slightly greater at 50 microg/ml than at 10 microg/ml. Our results suggest that FUT has protective effects against porcine hepatocytes in human plasma, and our PUF-HAL using porcine hepatocytes can function in human plasma for about 48 hours with FUT.

Alanine Transaminase↗
PubMed2001

Mass preparation of primary porcine hepatocytes and the design of a hybrid artificial liver module using spheroid culture for a clinical trial.

To isolate a large number of porcine hepatocytes, we originally developed a mass preparation method that combined the usual collagenase perfusion method of a whole liver with a collagenase redigestion method of tissue fragments after liver perfusion. Using a pig of 10kg, collagenase perfusion only resulted in a yield of 63+/-78 x 10(8) total cells with a viability of 69.2+/-25.3 %, but our combined method had a yield of 167+/-31 x 10(8) total cells with a viability of 87.9+/-4.4% (mean +/- SD). Also, the combined method was applied to two pigs of 10kg body weight at the same time, and isolated 387+/-89 x 10(8) hepatocytes with a viability of 87.1+/-6.9% and a purity of 93.6+/-2.8 % in 11 experiments. We designed a large multi-capillary polyurethane foam (MC-PUF) packed-bed module containing 1 x 10(10) porcine hepatocytes on a clinical trial scale. The porcine hepatocytes in the module formed spherical multicellular aggregates (spheroids) of 200 - 500 microm diameter. Most hepatocytes forming spheroids were viable judged by fluorescein diacetate and ethidium bromide staining. The activities of ammonia removal, albumin secretion and oxygen consumption of the large MC-PUF module were the same as for a small MC-PUF module containing 2 x 10(8) porcine hepatocytes, and were maintained for at least 9 days of culture. These results show that a large MC-PUF module is successfully scaled up 50 times. In conclusion, we succeeded in developing a mass preparation method of porcine hepatocytes and a large hybrid artificial liver module on a clinical trial scale.

Animals↗
PubMed2001

Polyurethane foam/spheroid culture system using human hepatoblastoma cell line (Hep G2) as a possible new hybrid artificial liver.

The risk of xenozoonosis infections poses the greatest obstacle against the clinical application of hybrid artificial liver support system (HALSS). Primary human hepatocytes are an ideal source for HALSS, but the shortage of human livers available for hepatocyte isolation limits this modality. To resolve this issue, we used human hepatocytes with replication capacity (fetal hepatocytes, Hep G2, and Huh 7) in a polyurethane foam (PUF)/spheroid culture system in vitro, and analyzed liver functions such as ammonia removal and albumin synthesis capacity; results were compared to those of porcine hepatocytes. Human fetal hepatocytes, Hep G2, and Huh 7 formed spheroids spontaneously within 24 h in a PUF/spheroid culture system; ammonia removal activity (micromol/10(6) nuclei/h) was upregulated, as was albumin synthesis activity (microg/10(6) nuclei/day). In particular, Hep G2 spheroids demonstrated high ammonia removal and albumin synthesis activities: 85% of the ammonia removal activity and 171.7% of the albumin synthesis activity of porcine hepatocytes in the monolayer culture. These results indicate the possibility of the development of a multicapillary PUF (MC-PUF) packed-bed culture system of hepatocyte spheroids as a HALSS using Hep G2.

Albumins↗
PubMed2000

Expression of a system L neutral amino acid transporter at the blood-brain barrier.

Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA.

Amino Acid Transport Systems↗
PubMed2000

Biliary atresia with hyperandrogenic amenorrhea: case report.

The etiology of hyperandrogenic amenorrhea in a 16 year-old girl after a successful Kasai operation for biliary atresia was unclear. Delayed puberty and menarche were observed. There was no luteinizing hormone-follicular stimulating hormone surge. A provocative luteinizing hormone-releasing hormone test showed a normal response. Peripheral aromatization of androgens appeared to function normally. However, plasma levels of sex hormone-binding globulin and total testosterone were high and the free testosterone level was normal. The anovulatory menstrual cycle continued after menarche at 18 years of age. A combination of estrogen and progesterone therapy was effective. The etiology might be associated with delayed metabolic clearance of testosterone accompanied by the compensatory cirrhosis and portosystemic shunt.

Adolescent↗