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K Takeda

Publications and source records attributed to K Takeda.

At least 37 records · Page 2Linked to original sources

On the origin of six-rowed barley with brittle rachis, agriocrithon [Hordeum vulgare ssp. vulgare f. agriocrithon (Aberg) Bowd.], based on a DNA marker closely linked to the vrs1 (six-row gene) locus.

The origin of six-rowed cultivated barley has been revealed to be more complex since the discovery of agriocrithon, a six-rowed barley with brittle rachis. The present study investigates whether such six-rowed brittle barley is wild or hybrid in nature, by analyzing genetic diversity at the cMWG699 marker locus, which is closely linked to the vrs1 (six-row gene) locus. DNA sequence analysis for 42 accessions showed only three types in six-rowed brittle barleys; in contrast, nine sequence types were found in ten wild barleys, ssp. spontaneum, in our previous study. Nucleotide diversities for the six-rowed brittle barley were 2.8-4.5 times lower than that for the ssp. spontaneum at this marker locus. The three sequence types found in the six-rowed brittle barley also appeared in the six-rowed cultivated barley. A cross-allelism test confirmed that the six-rowed character of the six-rowed brittle barley was controlled by the vrs1 locus. The nucleotide diversity and genealogy demonstrated that f. agriocrithon does not have the same level of diversity as found in wild barley, ssp. spontaneum. Consequently, f. agriocrithon does not appear to represent genuinely wild populations, but more probably originated from hybridization between ssp. spontaneum and six-rowed cultivated barley.

Alleles↗

Indications for hepatic vein reconstruction in living donor liver transplantation of right liver grafts.

BACKGROUND: To overcome problems arising from a graft of insufficient size, right liver grafts have been used extensively for adult-to-adult living donor liver transplantation (LDLT). However, there are reports of severe congestion in the anterior segment of the graft after transplantation. CASE REPORTS: Right liver transplantation without the middle hepatic vein was performed in six cases. In the second and third cases, the inferior right hepatic vein was reconstructed because it was thick (whereas the middle hepatic vein was not). Abdominal CT revealed congestive infarction of the anterior segment in the second case and of the posterior segment in the third. It was suspected that the former resulted from the lack of an middle hepatic vein, and the latter from obstruction of the reconstructed inferior right hepatic vein. Both patients died without improvement in liver function. Accordingly, in the fifth case, the middle hepatic vein was reconstructed. The postoperative course of this case was uneventful. Doppler ultrasonography showed profuse blood flow in the interposition graft. In the sixth case, the middle hepatic vein was not reconstructed because of technical difficulties. Although abdominal CT showed a congestive area in the anterior segment, the patient recovered uneventfully, probably because the volume of functional graft was sufficient even without the congestive area. CONCLUSION: When the color becomes dark in more than half of the surface of the anterior segment following clamping of middle hepatic vein tributaries and the hepatic artery, the middle hepatic vein should be reconstructed. When the diameter of the inferior right hepatic vein is more than 5 mm, its reconstruction is also recommended.

Adult↗

Usefulness of artificial liver support for pretransplant patients with fulminant hepatic failure.

This study assessed the usefulness of artificial liver support (ALS) for pretransplant patients with fulminant hepatic failure (FHF). Five patients (age 14 to 52 years, 3 men and 2 women) with FHF who were being prepared for living donor liver transplantation (LDLTx) were enrolled in this study. ALS included plasma exchange, using 40 to 50 units of fresh frozen plasma per session, and high-flow hemodiafiltration, using a high-performance polysulfone membrane. Variables such as circulatory and respiratory function, coma grade, and neurologic disorders were evaluated. Although systolic and diastolic blood pressures showed no statistical differences between pre-ALS and post-ALS, the difference in heart rates was statistically significant. After ALS initiation in the pre-LDLTx period, one of the three patients who needed mechanical ventilation was weaned from it. After LDLTx, all patients recovered neurologically; no neurologic disorder was observed. These results suggested that ALS could predict neurologic status after LDLTx. The difference in coma grades also achieved statistical significance. Our study indicates that short-term ALS is useful for improving circulatory and respiratory function prior to liver transplantation, as well as for predicting posttransplantation neurologic status. Although some patients recover by ALS alone, the survival rate of ALS-only patients is less than 50%. ALS prolongs intensive treatment, thus increasing both the risk of infection and the medical costs. Further investigation to determine a precise marker for liver regeneration will be needed to establish a consensus on the indications for long-term ALS. We conclude that ALS is useful to improve circulatory and respiratory functions among pretransplant patients, and to predict neurologic status after LDLTx.

Adolescent↗

Usefulness of the prognostic score for donor safety in living donor liver transplantation.

This study sought to determine whether a prognostic score is a useful indicator of donor safety using 13 consecutive donors enrolled for liver transplantation. The donor operations were right hepatic lobectomies (n = 10) and left hepatic lobectomies (n = 3). The postoperative maximal level of serum total bilirubin was used to assess the magnitude of surgical stress. Variables such as donor age, percentage of liver resection (PLR), indocyanine green 15-minute retention rate (ICGR15), operative blood loss, operation time, prognostic score and graft weight were evaluated as predictors of the magnitude of surgical stress. The PLR and prognostic score (PS) were calculated according to the following formulae: PLR (%) = 100*Graft weight (g)/standard liver volume of the donor (mL); PS = -84.6 + 0.933*PLR (%) +1.11*ICGR15 (%) +0.999*age (years); Standard liver volume (mL) = 706.2*body surface area (m2) + 2.39. No serious complications occurred after the donor operations. Maximal bilirubin ranged from 1.9 to 10.9 mg/dL. There were no mortalities, although there were two morbidities, bile leakage and prolonged liver dysfunction. Postoperative hyperbilirubinemia was observed in two donors and in one Gilbert's syndrome donor. Linear regression analysis of each variable indicated poor correlations between those variables and maximal bilirubin. However, close correlations were seen between maximal bilirubin and both donor age and PS except for the three patients who showed postoperative hyperbilirubinemia. In these uneventful donors, statistical formulae were obtained as follows: maximal bilirubin (PMB) = 0.271 + 0.056*donor age (correlation coefficient 0.612, P < .008), PMB = 1.541 + 0.059*PS (correlation coefficient 0.597, P < .009). In conclusion, PS is useful to predict maximal bilirubin and to ensure donor safety.

Age Factors↗

Surveillance of perioperative infections after adult living donor liver transplantation.

AIM: This study was conducted to clarify the management of perioperative infectious complications after adult living donor liver transplantation (LDLT). PATIENTS AND METHODS: Fourteen adult LDLT patients were enrolled in this study. We examined the occurrence of infectious complications in these cases and the relationships of infectious complications to UNOS status and MELD score. Surveillance culture and immunoserologic analyses were performed. From the results of these analyses, we made a diagram of infection surveillance using a matrix of time and sampling site. Using the diagram, we chose sensitive antibiotics as soon as possible. RESULTS: The infection site and its pathogen were able to be detected in four (28.5%) patients, all of whom had MRSA infections, together with lung aspergillosis in one case, pseudomonas pneumonia in another, and both in another. Two patients died of lung aspergillosis. Bacteria detected in the airway tended to spread to other sites during the postoperative period. In all four patients in whom infectious diseases were detected, and in a fifth patient in whom the site of infection was not known, the UNOS status was 1. The MELD score was calculated in eight patients, six of whom had high MELD scores (>20). CONCLUSION: Most cases were manageable by choosing and changing antibiotics and antifungal drugs according to the results of surveillance cultures twice a week. However, aspergillosis had an extremely poor prognosis. Patients with a high MELD score or low UNOS status, or both, showed poor prognosis; and in them, multiple drug resistance bacteria caused severe perioperative infectious complications.

Adult↗

Development and initial characterization of xenomitochondrial mice.

Xenomitochondrial mice harboring trans-species mitochondria on a Mus musculus domesticus (MD) nuclear background were produced. We created xenomitochondrial ES cell cybrids by fusing Mus spretus (MS), Mus caroli (MC), Mus dunni (Mdu), or Mus pahari (MP) mitochondrial donor cytoplasts and rhodamine 6-G treated CC9.3.1 or PC4 ES cells. The selected donor backgrounds reflected increasing evolutionary divergence from MD mice and the resultant mitochondrial-nuclear mismatch targeted a graded respiratory chain defect. Homoplasmic (MS, MC, Mdu, and MP) and heteroplasmic (MC) cell lines were injected into MD ova, and liveborn chimeric mice were obtained (MS/MD 18 of 87, MC/MD 6 of 46, Mdu/MD 31 of 140, and MP/MD l of 9 founder chimeras, respectively). Seven MS/MD, 1 MC/MD, and 11 Mdu/MD chimeric founder females were mated with wild-type MD males, and 18 of 19 (95%) were fertile. Of fertile females, only one chimeric MS/MD (1% coat color chimerism) and four chimeric Mdu/MD females (80-90% coat color chimerism) produced homoplasmic offspring with low efficiency (7 of 135; 5%). Four male and three female offspring were homoplasmic for the introduced mitochondrial backgrounds. Three male and one female offspring proved viable. Generation of mouse lines using additional female ES cell lineages is underway. We hypothesize that these mice, when crossbred with neurodegenerative-disease mouse models, will show accelerated age-related neuronal loss, because of their suboptimal capacity for oxidative phosphorylation and putatively increased oxidative stress.

Animals↗

IL-18 gene therapy develops Th1-type immune responses in Leishmania major-infected BALB/c mice: is the effect mediated by the CpG signaling TLR9?

IL-18 regulates either Th1 or Th2 responses depending on the cytokine microenvironment. Administration of recombinant IL-18 (rIL-18) alone does not promote Th1 response, but rather induces Th2 response and exacerbates Leishmania major infection in susceptible BALB/c mice. Here, we treated BALB/c mice with an IL-18-expressing plasmid by using a gene gun weekly after L. major infection. This gene therapy resulted in improved pathogenic process and preferential induction of Th1 responses by inducing the expression of IL-12 p40, but treatment with rIL-18 did not. Notably, simultaneous administration of rIL-18 with an empty plasmid vector rendered BALB/c mice resistant to the infection, despite the fact that treatment with either rIL-18 alone or the plasmid vector alone did not influence the susceptibility. The synergistic role of the vector with rIL-18 was found to depend on CpG motifs, which enhanced expression of proinflammatory cytokines, especially IL-12, from APCs through Toll-like receptor (TLR) 9 ligation. Treatment with methylated plasmid vector in which CpG was disrupted could no longer prevent the disease development in coadministration with rIL-18. Taken together, IL-18 gene therapy was shown to develop Th1-type protective immunity in L. major-infected BALB/c mice without the requirement of exogenous IL-12, probably via CpG-TLR9 signaling pathway.

Animals↗

In vivo transfection of a cis element 'decoy' against signal transducers and activators of transcription 6 (STAT6)-binding site ameliorates IgE-mediated late-phase reaction in an atopic dermatitis mouse model.

Signal transducers and activators of transcription 6 (STAT6) play a crucial role in the transactivation of IL-4 and IL-13, which might be involved in the pathogenesis of atopic dermatitis (AD). We herein reported that the IgE-mediated late-phase reaction significantly decreased in STAT6-deficient (STAT6(-/-)) mice in AD model mice induced by intravenous injection of monoclonal anti-dinitrophenyl (DNP)-IgE antibody and subsequent skin testing with dinitrofluorobenzene. We therefore hypothesized that synthetic double-stranded DNA with a high affinity for STAT6 could be introduced in vivo as decoy cis elements to bind the transcriptional factor and block the gene activation contributing to the onset and progression of AD, thus providing effective therapy for AD. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODNs), but not scramble decoy ODN after sensitization by anti-DNP-IgE antibody, had a significant inhibitory effect on not only STAT6 binding to nuclei but also on the late-phase response. A histological analysis revealed that both edema and the infiltration of neutrophils and eosinophils significantly decreased in STAT6 decoy ODN-transfected mice. To examine the mechanism of the in vivo effect of STAT6 decoy ODN, we employed an in vitro mast cells culture system. After IgE receptor engagement, mast cells transfected by STAT6 decoy ODN exhibited normal histamine release, but their cytokine release (TNF-alpha, IL-6) markedly decreased. We herein report the first successful in vivo transfer of STAT6 decoy ODN to reduce the late-phase reaction, thereby providing a new therapeutic strategy for AD.

Animals↗

In vivo transfection of a cis element 'decoy' against signal transducers and activators of the transcription 6 (STAT6) binding site ameliorates the response of contact hypersensitivity.

We herein demonstrate that STAT6 plays an important role in the induction of not only acute contact hypersensitivity (CHS), but also chronic CHS in a mouse model using STAT6-deficient (STAT6(-/-)) mice. We, therefore, determine whether synthetic double-stranded DNA with a high affinity for STAT6 can be introduced in vivo as a decoy cis element to bind the transcriptional factor and block the induction of not only acute CHS but also chronic CHS. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODN), after the induction of 2,4,6-trinitrochlorobenzene or other haptens had a significant inhibitory effect on the induction of both acute CHS and chronic CHS. We thus examined the mechanism of the in vivo effect of the transfection of STAT6 decoy ODN in both acute and chronic CHS. In the histological analysis, the infiltration of eosinophils and degranulated mast cells, and the production of IL-4, IL-6 and eotaxin, but not IFN-gamma in the extracts from challenged skin significantly decreased by the transfection of STAT6 decoy ODN. We herein report the first successful in vivo transfer of STAT6 decoy ODN to inhibit acute and chronic CHS, thus providing a new therapeutic strategy not only for the treatment of CHS but also for atopic dermatitis.

Acute Disease↗

Pharmacokinetics and pharmacodynamics of febuxostat (TMX-67), a non-purine selective inhibitor of xanthine oxidase/xanthine dehydrogenase (NPSIXO) in patients with gout and/or hyperuricemia.

The diurnal change of sUA and the effect of febuxostat on this change were investigated in 10 patients with gout and/or hyperuricemia. The diurnal sUA change after the last dose during the 4-week treatment phase (20 mg, QD) was almost the same as the pre-treatment value. Considering the dose, the AUC(obs) and Cmax of unchanged drug in patients with gout and/or hyperuricemia were estimated to be similar to those of healthy male adults. The results show that a 6-week treatment with febuxostat is safe and well-tolerated in the target patient population for this drug.

Area Under Curve↗

[A rational approach of limited resection for small peripheral lung adenocarcinoma with curative intent; analyses of multiple primary adenocarcinomas].

Hundred and forty-one small peripheral adenocarcinomas 2 cm or less in diameter were retrospectively studied to determine the rationale of limited resection with curative intent. We used a conventional computed tomography (CT) which used 2.5 mm thick sections to examine only the main tumor during from March 1985 to May 1999 and a spiral CT which produced 2.5 mm thick sections of the entire lung field during from June 1999 to July 2003. The incidence of small peripheral adenocarcinoma significantly increased from 12.6% to 29.1%, suggesting an increase in the rate of detection with spiral CTs. During the spiral CT era, the percentage of females, pathological stage I a tumors, predominant ground-glass opacity (GGO) tumors and limited resection were significantly higher. The incidence of multiple adenocarcinomas 2 cm or less in diameter significantly increased 2.6% to 14.1%. It increases to 21.9% in small adenocarcinomas and 63.6% in predominant GGO type, when minute GGO lesion which have been followed in 5 patients by a watch and wait policy would be bronchioloalveolar carcinoma (BAC). In conclusion, a paradigm shift of the treatment for small peripheral adenocarcinoma should be warrant, because localized BAC as noninvasive cancer is not rare and often found as multiple BACs.

Adenocarcinoma↗

Efficient construction of high-density linkage map and its application to QTL analysis in barley.

Using a High Efficiency Genome Scanning (HEGS) system and recombinant inbred (RI) lines derived from the cross of Russia 6 and H.E.S. 4, a high-density genetic map was constructed in barley. The resulting 1,595.7-cM map encompassed 1,172 loci distributed on the seven linkage groups comprising 1,134 AFLP, 34 SSR, three STS and vrs1 (kernel row type) loci. Including PCR reactions, gel electrophoresis and data processing, 6 months of work by a single person was sufficient for the whole mapping procedure under a reasonable cost. To make an appraisal of the resolution of genetic analysis for the 95 RI lines based on the constructed linkage map, we measured three agronomic traits: plant height, spike exsertion length and 1,000-kernel weight, and the analyzed quantitative trait loci (QTLs) associated with these traits. The results were compared on the number of detected QTLs and their effects between a high-density map and a skeleton map constructed by selected AFLP and anchor markers. The composite interval mapping on the high-density map detected more QTLs than the other analyses. Closely linked markers with QTLs on the high-density map could be powerful tools for marker-assisted selection in barley breeding programs and further genetic analyses including an advanced backcross analysis or a map-based cloning of QTL.

Chromosome Mapping↗

Increase of Th1 type cytokine mRNA expression in peripheral blood lymphocytes of calves experimentally infected with Cryptosporidium parvum.

The expression of the messenger RNA of interleukin-12 (IL-12), interferon-gamma, interleukin-4, interleukin-6, and interleukin-10 was examined by reverse-transcriptase polymerase chain reaction in peripheral blood lymphocytes of calves that were orally inoculated with Cryptosporidium parvum oocysts. In all of the calves, gene expression of interleukin-12, interleukin-6, and interferon-gamma was observed at delivery and this expression was repressed within the next 24h. In calves inoculated with C. parvum, mRNA expression of interleukin-12 and interferon-gamma was noticed on day 3 post-inoculation (p.i.) and increased in the convalescent phase of the infection, whereas in non-inoculated calves no mRNA expression was detectable up to the end of the experiment. No mRNA expression of interleukin-4 or 6 was detected during the experiment. Our observations suggest that systemic Th1 type immune responses are induced in calves infected with C. parvum and may be available for evaluation of the control of the infection.

Animals↗

Analysis of cytokine regulators inducing interferon production by mouse uterine natural killer cells.

In mice and women, terminal differentiation of uterine natural killer (uNK) cells commences during endometrial decidualization. Both proliferation and interferon (IFN)-gamma are induced. Uterine NK cell precursors appear to home from secondary lymphoid organs to decidualizing uteri and localize mesometrially to the central decidua basalis, the site of maternal arterial modification at Gestation Days (gd) 9.5-10. In mice, genetic absence of uNK cells results in absence of pregnancy-induced spiral artery modification. Administration of IFN-gamma to uNK-negative pregnant females induces arterial modifications without fetal loss. In this study, we investigated the roles of cytokines, known in other tissues to differentiate and activate NK cells, in induction of IFN-gamma production in normal mouse implantation sites. Fecundity evaluation, implantation site morphometry, and IFN-gamma quantification in interleukin (IL)-12p40(0/0), IL-18(0/0), dual IL-12p40(0/0)/IL-18(0/0) and congenic strains revealed the importance of both IL-12 and IL-18 in the induction of spiral artery modification and IFN-gamma synthesis. Immediately after implantation, IL-18 was localized transiently to decidual cells, but by gd8, IL-18 was produced solely by uNK cells, suggesting that early uNK cells are activated by stroma and lymphocyte-derived signals maintain later uNK cell activation. Mesometrial tissue of C57Bl/6J mice was examined by reverse transcription polymerase chain reaction assay in virgin, early postimplantation, and midgestation females for expression of the heterodimeric cytokines IL-23 (composed of IL-12p40 and a novel alpha chain), IL-27 (composed of two IL-12-related chains) and IL-27R. No expression was detected in virgin uteri. The four genes were induced by gd6, and uNK cells isolated from midgestation transcribed IL-23alpha and IL-27R. This study advances the understanding of uNK cell activation during normal pregnancy.

Animals↗