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T Takeda

Publications and source records attributed to T Takeda.

At least 289 records · Page 16Linked to original sources
PubMed1998

Effect of exercise on tibial and lumbar vertebral bone mass in mature osteopenic rats: bone histomorphometry study.

The effect of moderate running exercise on tibial and lumbar vertebral bone mass was examined in mature osteopenic rats by bone histomorphometry. Ten 37-week-old female Wistar rats, with bone loss resulting from being fed a relatively low-calcium diet for 14 weeks after ovariectomy at the age of 23 weeks, were randomly divided into two groups of five animals each; control and exercise groups. The exercise consisted of treadmill running at 12 m/min for 1 h per day on 5 days per week for 12 weeks. During the exercise period, all animals were fed a standard calcium diet. After 12 weeks of exercise, bone histomorphometry was evaluated for cancellous bone (secondary spongiosa) of the proximal tibia and the fourth lumbar vertebra and for cortical bone of the tibial shaft. The findings suggested that in the mature osteopenic rat, there was a beneficial effect of moderate running exercise with adequate calcium intake on bone mass only in a weight-bearing long bone, the tibia. The mechanism for increased bone mass appeared to be both decreased bone resorption and increased bone formation in cancellous bone and increased bone formation in cortical bone.

Analysis of Variance↗
PubMed1998

Long-term consequence of endoscopic sphincterotomy for bile duct stones.

BACKGROUND: There are many reports of early- and intermediate-term results of endoscopic sphincterotomy. However, few data are available on long-term clinical outcome of endoscopic sphincterotomy for removal of common bile duct stones. METHODS: Of 419 patients who underwent endoscopic sphincterotomy, follow-up data were obtained in 410 patients (98%). The period ranged from 1 month to 20 years (average 122 months). RESULTS: Late complications included recurrence of stones (12.3%), acute cholangitis, acute cholecystitis (22% of 32 patients with gallstones, 0% of 88 patients without gallstones), new gallstone formation (6 patients), liver abscess (5 patients), and biliary carcinoma (8 patients). All of the recurrent stones were bilirubinate irrespective of the type of stone at sphincterotomy. Cholangitis and liver abscess occurred in 31% and 11%, respectively, of patients with residual intrahepatic stones but not in patients with complete intrahepatic stone clearance. CONCLUSIONS: Late complications occur in a considerable proportion of patients after endoscopic sphincterotomy for the treatment of common bile duct stones, including stone recurrence, acute cholecystitis (which occurs only in patients with gallstones), liver abscess in patients with residual intrahepatic stones, and biliary carcinoma. The fact that the recurrent stones are invariably of the bilirubinate type, irrespective of the type of stones at initial treatment, suggests that bacterial infestation due to ablation of the sphincter mechanism may have a causative role.

Adult↗
PubMed1998

Stimulation of interleukin-8 production by acidic polysaccharides from the root of Panax ginseng.

The root of Panax ginseng C.A. Meyer, is a well-known important Chinese traditional medicine used as a stomachic, tonic, sedative and as an elixir called Ginseng in China and Japan. The precise mechanism of the biological actions of this plant is not fully understood. In order to elucidate the immunomodulating activities of this plant, we examined the direct effects of four of its components, acidic polysaccharides isolated in previous studies, on cytokine (interleukin-8; IL-8) production by a human monocytic cell line, THP-1, and human blood monocytes in vitro, as IL-8 is a potent inflammatory cytokine involved in neutrophil chemotaxis and activation. We found that one component, ginsenan S-IIA, is a potent inducer of IL-8 production by human monocytes and THP-1 cells, and this induction is accompanied by increased IL-8 mRNA expression.

Adjuvants, Immunologic↗
PubMed1998

Purification and characterization of ascorbate peroxidase in Chlorella vulgaris.

Chlorella vulgaris contained only one isoform of ascorbate peroxidase (AsAP) as the hydrogen peroxide (H2O2)-scavenging system except for catalase at a specific activity of 3.3 +/- 0.2 units/mg protein. The activity of glutathione peroxidase was not detected in the extracts from cells grown in the absence and presence of sodium selenite. We detected the activity of monodehydroascorbate reductase involved in the regeneration of ascorbate, but we failed to detect the dehydroascorbate reductase activity. AsAP has been purified to electrophoretic homogeneity from Chlorella cells. The enzyme was a monomer with a molecular mass of 32 kDa using gel filtration and SDS-polyacrylamide gel electrophoresis. The enzyme showed higher specificity with ascorbate than with pyrogallol. The K(m) values of the enzyme for ascorbate and H2O2 were 111 +/- 8.9 and 20 +/- 2.5 microM, respectively. When the enzyme was diluted with the ascorbate-deleted medium, the half inactivation time was approximately 15 min. The absorption spectra of the purified enzyme and the inhibition by cyanide and azide showed that it is a hemoprotein. The enzyme was markedly inhibited by 0.2 mM p-chloromercuribenzoate. The enzyme cross-reacted by immunoblotting with the monoclonal antibody raised against Euglena cytosolic AsAP. The amino acid sequences in the N-terminal region of Chlorella AsAP showed no significant similarity to any other AsAPs from higher plants and algae.

Amino Acid Sequence↗
PubMed1998

Effect of artificial endolymph injection into the cochlear duct on the endocochlear potential.

We investigated the effect of acute endolymphatic hydrops on the positive endocochlear potential (+EP) and negative endocochlear potential (-EP). The +EP was measured in guinea pigs during injection (without outlet) and perfusion (with outlet) of artificial endolymph into the cochlear duct. The -EP was measured during anoxia after the injection or the perfusion had finished. Injection of artificial endolymph produced a slight transient increase in the +EP, and a significant decrease in the magnitude of the -EP. Chronic endolymphatic hydrops produces both +EP and -EP decrease. The +EP decrease in chronic endolymphatic hydrops may cause the chronic change of the inner ear. The +EP increase in acute endolymphatic hydrops may be caused by a shift of the basilar membrane. However, the mechanism of the 'transient' +EP increase is not clear. The -EP decrease was not observed in animals whose cochlear duct was perfused with artificial endolymph. Therefore, the artificial endolymph itself did not cause the decrease in magnitude of the -EP. Dysfunction of the hair cells is a possible explanation for the -EP decrease but the mechanism of such a decrease is not clear in the present study. However, the results of this study support the notion that small increases in endolymphatic pressure below the resolution of recent measurements (DeMott and Salt, 1997) can lead directly to a reduction of the -EP during hydrops. The animal model described here can eliminate the chronic effect of hydrops, therefore, this model is useful for investigations into the effect of hydrops itself on the inner ear and the mechanism of hearing loss in Ménière's disease.

Action Potentials↗
PubMed1998

Presence of mRNA for vasoactive intestinal polypeptide (VIP) and its receptor in the rat inner ear.

Although mechanisms regulating inner ear fluid have not been yet elucidated, control of blood flow has been thought to be of great importance. Vasoactive intestinal polypeptide (VIP) was the first neuropeptide demonstrated in cerebrovascular nerves. To study the possible role of VIP in regulation of inner ear fluid, we investigated the presence of mRNA for VIP and VIP receptor in the rat inner ear using a reverse transcription-polymerase chain reaction (RT-PCR) method. A single band of the size expected for VIP and its receptor was detected in mRNA from the rat inner ear by using primers specific for VIP and the receptor. The nucleotide sequences of the subcloned RT-PCR products were identical to those of rat VIP and the rat lung VIP receptor. These results indicate that both VIP and VIP receptor are expressed in the inner ear of the rat and suggest that VIP may be implicated in regulation of fluid in the inner ear.

Animals↗
PubMed1998

Mutational analysis of the N-ras gene in acute lymphoblastic leukemia: a study of 125 Japanese pediatric cases.

A point mutation of the N-ras gene is one of the known genetic alterations identified in patients with acute lymphoblastic leukemia (ALL), but its clinical importance is still controversial. Using polymerase chain reactions, we examined codons 12, 13 and 61 of this gene in 125 Japanese childhood ALL patients (64 common-ALL, 22 pre-B-ALL, 33 T-ALL, 2 B-ALL, 3 undifferentiated ALL, and 1 unclassified ALL) including 9 relapsed patients. An N-ras point mutation was observed in 14 (11%) patients (9 common-ALL, 3 T-ALL, and 2 undifferentiated ALL; 13 patients at diagnosis and 1 at relapse). The patients with undifferentiated ALL harbored an N-ras mutation at a significantly higher rate. However, no correlation was found between the presence of an N-ras mutation and sex, age, or white blood count. There was no significant difference in the event-free survival rate between 13 fresh patients with an N-ras mutation and 103 patients with a wild-type configuration. The N-ras mutation was present in about 10% of childhood ALL cases but it did not have a prognostic impact. The sequence analyses revealed that the majority of the patients (13/14) had an N-ras mutation of a G to A transition. This finding was consistent with previous reports on N-ras mutations in acute leukemias in which the incidence of a G to A mutation was significantly higher in ALL than in myeloid malignancies.

Child↗
PubMed1998

Verotoxins induce apoptosis in human renal tubular epithelium derived cells.

Apoptosis mediated by verotoxins (VTs) has been identified in a renal carcinoma cell line, ACHN cells, which are an in vitro model of renal tubular epithelial cells. ACHN cells express the renal tubular marker CD24 as well as globotriaosyl ceramide/CD77, the receptor for VTs. VT binding to the ACHN cell surface was confirmed by positive staining with antibodies to the VTs. Treatment of ACHN cells with VTs induced prompt growth inhibition and cell death, and fragmentation of the genomic DNA in cells, typical of apoptosis, was observed. The expression of apoptotic antigen 7A6 detected by APO2.7 antibody in ACHN cells further supports the occurrence of apoptosis as a result of VT treatment. Cycloheximide enhanced VT-mediated apoptosis of ACHN cells, suggesting a strong correlation between the inhibition of protein synthesis and VT-mediated apoptosis. Moreover, tumor necrosis factor-alpha had a synergistic effect on VT-mediated apoptosis in ACHN cells. Considering the above evidence together with the clinical evidence showing the presence of apoptosis in the renal epithelium of a HUS patient, our results suggest a VT-induced apoptotic mechanism in normal renal tubular epithelium that may contribute to the pathogenesis of hemolytic uremic syndrome.

Antigens, Surface↗
PubMed1998

Induction of apoptosis in normal human renal tubular epithelial cells by Escherichia coli Shiga toxins 1 and 2.

The cytotoxicity of Shiga toxin (Stx) 1 and Stx2 produced by Escherichia coli to human renal cortical epithelial cells (HRCEC) in primary culture was investigated. HRCEC express CD24, the marker of renal distal tubules, as well as globotriaosyl ceramide/CD77, the receptor for Stxs. Binding of Stxs to HRCEC was confirmed by positive staining with specific antibodies to Stxs. Treatment of HRCEC with Stxs induced rapid cell death, which was reversed in the presence of neutralizing antibody specific for Stx. DNA fragmentation was found to be accompanied by Stx-mediated cell death in HRCEC, indicating that apoptosis was part of the process. These data and previous reports indicate that a variety of renal cell types, including tubular epithelial cells as well as glomerular capillary endothelial cells, may be targets for Stx-mediated apoptosis, which could contribute to the pathogenesis of hemolytic-uremic syndrome caused by Stx-producing E. coli infection.

Adult↗
PubMed1998

Isolation of tick-borne encephalitis virus from Ixodes ovatus (Acari: Ixodidae) in Japan.

A case of tick-borne encephalitis (TBE) was found in a farming area located in the southern part of Hokkaido, Japan, in 1993. TBE viruses were isolated from sentinel dogs in the area where the human case occurred in 1995. Ticks were collected in the area by 2 collection methods in 1995 and virus isolation was conducted on ticks in 1995 and 1996. Ixodes ovatus Neumann was found to be the predominant tick species in the area. In 1996, 2 virus strains were isolated from 600 I. ovatus ticks (300 females and 300 males), giving the minimum infection rate of 0.33% (2 of 600). The 2 virus strains were identified as TBE virus by antigenic analysis using monoclonal antibodies and the indirect immunofluorescent antibody test. The results showed that I. ovatus was a suspected vector of the emerging TBE virus in Hokkaido.

Animals↗
PubMed1998

Molecular characterization and physiological role of a glyoxysome-bound ascorbate peroxidase from spinach.

cDNAs encoding two cytosolic and two chloroplastic ascorbate peroxidase (AsAP) isozymes from spinach have been cloned recently [Ishikawa et al. (1995) FEBS Lett. 367: 28, (1996) FEBS Lett. 384: 289]. We herein report the cloning of the fifth cDNA of an AsAP isozyme which localizes in spinach glyoxysomes (gAsAP). The open reading frame of the 858-base pair cDNA encoded 286 amino acid residues with a calculated molecular mass of 31,507 Da. By determination of the latency of AsAP activity in intact glyoxysomes, the enzyme, as well as monodehydroascorbate (MDAsA) reductase, was found to be located on the external side of the organelles. The cDNA was overexpressed in Escherichia coli (E. coli). The enzymatic properties of the partially purified recombinant gAsAP were consistent with those of the native enzyme from intact glyoxysomes. The recombinant enzyme utilized ascorbate (AsA) as its most effective natural electron donor; glutathione (GSH) and NAD(P)H could not substitute for AsA. The substrate-velocity curves with the recombinant enzyme showed Michaelis-Menten type kinetics with AsA and hydrogen peroxide (H2O2); the apparent Km values for AsA and H2O2 were 1.89 +/- 0.05 mM and 74 +/- 4.0 microM, respectively. When the recombinant enzyme was diluted with AsA-depleted medium, the activity was stable over 180 min. We discuss the H2O2-scavenging system maintained by AsAP and the regeneration system of AsA in spinach glyoxysome.

Amino Acid Sequence↗
PubMed1998

Long survivors with Ki-1 lymphoma having t(2;5) (p23;q35). Does the presence or absence of t(2;5) influence the prognosis of patients with Ki-1 lymphoma?

We experienced three patients with CD30+ diffuse large cell lymphoma having chromosomal abnormalities. The first patient was an 8-year-old girl with bilateral cervical lymphadenopathy. A biopsy of a cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and a chromosomal abnormality, t(2;5). She attained a remission and is now in complete remission 108 months after diagnosis, despite frequent relapses. The second patient was a 13-year-old boy with right axillar and supraclavicular lymph-node adenopathy. A biopsy of a cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and a chromosomal abnormality, t(2;5). He attained remission and was in continuous first remission 112 months after diagnosis. The third patient was an 11-year-old boy with fever and bilateral cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and chromosomal abnormality without t(2;5). He showed a very aggressive clinical course. Only the patients with Ki-1 lymphoma having t(2;5) survived over 100 months from the diagnosis, despite the advanced stage of the disease. These findings and a review of the literature showed that the presence or absence of t(2;5) may influence the outcome of Ki-1 lymphoma.

Adolescent↗
PubMed1998

[Anti-verotoxin-neutralizing antibody in intravenous gammaglobulin preparations].

Intravenously administered immune globulin therapy has been reported to be an effective treatment for serious patients with verotoxin-producing Escherichia coli infections while an efficacy for VT2 are under discussion. We therefore examined in vitro commercially available immune globulin preparations for the presence of anti-VT neutralizing antibodies in expectation of protecting a patient from serious complications as HUS. We examined 47 lots of gamma-globulin prepared by 5 pharmaceutical companies in Japan. Of them 29 lots were prepared from imported blood and 18 lots were from Japanese donors' blood. They were prepared in each company following their own manufactures' process. Neutralizing activity for VT1 and VT2 were determined by means of cytotoxicity using ACHN (renal adenocarcinoma, human) cells. All lots of gamma-globulin preparations from imported blood completely neutralized 125 pg/ml VT1 at the concentration of 12.5 mg/ml, and no significant difference was found in the manufactures' process. On the other hand gamma-globulin preparations from Japanese donors' blood neutralized VT1 five times less than the former. None of all preparations neutralized VT2. Gammaglobulin preparations were produced from pooled human plasma. To know the difference of neutralizing activities in the source, we examined randomly selected 239 human plasma samples of which 51 were from Japanese donors' blood and 188 were from imported blood. Prevalences of neutralizing activity of VT1 in imported plasma and domestic plasma were 10.6% and 2.0%, respectively. The prevalence of neutralizing antibody in these plasma samples reflects the different neutralizing activity of VT1 in gamma-globulin preparations prepared from imported blood and Japanese donors' blood. From these results, by selecting the lot of gamma-globulin preparations or the material of plasma with highly neutralizing activity, intravenously administered immune globulin therapy may be effective for VT1. The lack of VT2-neutralizing activity in any gamma-globulin preparation promotes us to develop humanized anti-VT2-monoclonal antibody for the prevention of HUS in high risk children.

Antibodies, Bacterial↗
PubMed1998

[Evaluation of immunochromatography-based rapid detection kit for fecal Escherichia coli O157].

"Quix" is an immunochromatography-based direct detection kit for the E. coli O157 LPS antigen in the patient's stool. The present study was conducted to evaluate the efficacy of the kit for rapid diagnosis of enterohemorrhagic Escherichia coli (EHEC) O157 infection. Sensitivity of the kit was determined using a pure culture of a clinical isolate of E. coli O157. Analytical sensitivity was found to be 5 x 10(5) CFU/ml. When compared with the culture method using fecal samples of 64 patients and with bloody diarrhea, sensitivity and specificity were 95.0% (19/20) and 86.4% (38/44), respectively, and overall agreement to culture method was 89.1% (57/64). One patient was found positive by culture method while negative in the present method, where the sample contained a low number of the cells less than the detection limit. Four of the six patients with a negative result by culture method and positive in the present method, were confirmed E. coli O157 infection by positive IgM antibody response against the E. coli O157 LPS. The discrepancy between the two methods seemed to be attributable to antibiotic administration. In one patient, Salmonella urbana (O30(1)30(2)) was detected. The O30(1) antigen of this bacterium is well known to be identical to the E. coli O157 antigen. When the present method was compared with an ELISA-based E. coli O157 LPS antigen detection kit, sensitivity and specificity were 100% (11/11) and 82.1% (23/28), and overall agreement to ELISA method was 87.2% (34/39). From these findings, Quix is useful as a rapid diagnostic kit in the primary clinics, outpatient or bedside use. E. coli O157 LPS antigen in patient's fecal samples can be detected in about five minutes with this simple procedure. Early diagnosis using such a simple kit will largely contribute for the early treatment and prevention of severe complications of the E. coli O157 infection.

Antigens, Bacterial↗
PubMed1998

[In vitro specific binding of Shiga toxin 1 and 2 by TAK-751S (Gb3 analog)].

TAK-751S is a synthetic trisaccharide coupled to Chromosorb P using a spacer sequence of 8-methoxycarboyloctyl (MCO). Its chemical structure is similar to a human receptor (Gb3) of Stx produced by enterohemorrhagic Escherichia coli (EHEC). In vitro efficacy of TAK-715S was studied by using ACHN cultured cell assay, which is sensitive and specific for measuring low level of Stx. Under various conditions, TAK-715S was mixed with purified Stx1 and Stx2, and residual free toxins in the solution were measured by using ACHN cells. TAK-715S was demonstrated to bind specifically to Stx1 and Stx2 under the condition similar to a human intestine while Chromsorb P did not bind to any Stx. The binding activity was stable in the presence of various processed foods, fresh vegetables and fruits. Antibiotics such as fosfomycin, kanamycin and norfloxacin did not disturb its binding capability. Minimum inhibitory concentrations of these antibiotics against Staphylococcus aureus FDA209P or E. coli NIHJ JC-2 neither changed after incubating with TAK-751S for 60 min at 37 degrees C. These results suggest that TAK-751S can be given orally with various foods and antibiotics for the elimination of Stx1 and Stx2 in the gut of patients with EHEC infections.

Adsorption↗
PubMed1998

Molecular analysis of non-O1, non-O139 Vibrio cholerae associated with an unusual upsurge in the incidence of cholera-like disease in Calcutta, India.

There was an inexplicable upsurge in the incidence of non-O1, non-O139 Vibrio cholerae among hospitalized patients admitted to the Infectious Diseases Hospital, Calcutta, India, between February and March 1996. Of the 18 strains of V. cholerae isolated during this period, 15 belonged to the non-O1, non-O139 serogroups (4 belonged to O144, 3 belonged to O11, 1 each belonged to O6, O8, O12, O19, O39, and O58, and 2 strains could not be typed), 2 belonged to the O139 serogroup, and 1 belonged to the O1 serogroup. Cell-free culture supernatants of 13 representative non-O1, non-O139 V. cholerae strains evoked a distinct cytotoxic effect on CHO and HeLa cells, and the strains examined produced the nonmembrane-damaging cytotoxin. By several PCR assays, it was determined that none of the non-O1, non-O139 strains were positive for the ctxA, zot, ace, and tcpA genes and for the genes representing the heat-labile toxin, heat-stable toxin, and verotoxin of Escherichia coli and the various variants of these genes. Studies on the clonality of non-O1, non-O139 V. cholerae strains by restriction fragment length polymorphism (RFLP) analysis of rRNA genes and of other genes (hlyA, hlyU, hlx, toxR, and attRS1) and by pulsed-field gel electrophoresis (PFGE) collectively indicate that the upsurge which occurred in February and March 1996 was caused by strains belonging to different clones. Overall, there was an excellent correlation between the results of ribotyping, RFLP analysis of various genes, and PFGE, with strains belonging to a particular serogroup showing nearly identical restriction patterns and PFGE profiles. It is clear from this study that some serogroups of V. cholerae can cause diarrhea by a mechanism quite different from that of toxigenic V. cholerae O1 and O139, and we have proposed the nomenclature of enteropathogenic V. cholerae to include these serogroups.

Bacterial Typing Techniques↗