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K Mochizuki

Publications and source records attributed to K Mochizuki.

At least 19 recordsLinked to original sources
PubMed2001

Syntheses, structures, and physicochemical properties of diruthenium compounds of tetrachlorocatecholate with metal-metal bonded Ru(3+)(mu-OR)(2)Ru(3+) and Ru(3.5+)(mu-OR)(2)Ru(3.5+) cores (R = CH(3) and C(2)H(5)).

Metal-metal bonded Ru(3+)(mu-OR)(2)Ru(3+) and Ru(3.5+)(mu-OR)(2)Ru(3.5+) (R = CH(3) and CH(3)CH(2)) compounds with tetrachlorocatecholate (Cl(4)Cat) have been synthesized in the corresponding alcohol, MeOH and EtOH, from a nonbridged Ru(2+)-Ru(3+) compound, Na(3)[Ru(2)(Cl(4)Cat)(4)(THF)].3H(2)O.7THF (1). In alcohol solvents, compound 1 is continuously oxidized by oxygen to form Ru(3+)(mu-OR)(2)Ru(3+) and Ru(3.5+)(mu-OR)(2)Ru(3.5+) species. The presence of a characteristic countercation leads to selective isolation of either Ru(3+)(mu-OR)(2)Ru(3+) or Ru(3.5+)(mu-OR)(2)Ru(3.5+) as a stable adduct species. In methanol, Ph(4)PCl and dibenzo-18-crown-6-ether afford Ru(3+)(mu-OMe)(2)Ru(3+) species, [A](2)[Ru(2)(Cl(4)Cat)(4)(mu-OMe)(2)Na(2)(MeOH)(6)] ([A](+) = Ph(4)P(+) (2), [Na(dibenzo-18-crown-6)(H(2)O)(MeOH)](+) (3)), while benzo-15-crown-5-ether provides a Ru(3.5+)(mu-OMe)(2)Ru(3.5+) species, [Na(benzo-15-crown-5)(2)][Ru(2)(Cl(4)Cat)(4)(mu-OMe)(2)Na(2)(MeOH)(6)] (4). The air oxidation of 1 in a MeOH/EtOH mixed solvent (1:1 v/v) containing benzo-15-crown-5-ether provides a Ru(3.5+)(mu-OMe)(2)Ru(3.5+) species, [Na(benzo-15-crown-5)(H(2)O)][Ru(2)(Cl(4)Cat)(2)(mu-OMe)(2)Na(2)(EtOH)(2)(H(2)O)(2)(MeOH)(2)].(benzo-15-crown-5) (5). Similarly, the oxidation of 1 in ethanol with Ph(4)PCl provides a Ru(3.5+)(mu-OEt)(2)Ru(3.5+) species, (Ph(4)P)[Ru(2)(Cl(4)Cat)(4)(mu-OEt)(2)Na(2)(EtOH)(6)] (7). A selective formation of a Ru(3+)(mu-OEt)(2)Ru(3+) species, (Ph(4)P)(2)[Ru(2)(Cl(4)Cat)(4)(mu-OEt)(2)Na(2)(EtOH)(2)(H(2)O)(2)] (6), is found in the presence of pyrazine or 2,5-dimethylpyrazine. The crystal structures of these compounds, except 2 and 7, have been determined by X-ray crystallography, and all compounds have been characterized by several spectroscopic and magnetic investigations. The longer Ru-Ru bonds are found in the Ru(3+)(mu-OR)(2)Ru(3+) species (2.606(1) and 2.628(2) A for 3 and 6, respectively) compared with those of Ru(3.5+)(mu-OMe)(2)Ru(3.5+) species (2.5260(6) A and 2.514(2) A for 4 and 5, respectively). These structural features and magnetic and ESR data revealed the electronic configurations of sigma(2)pi(2)delta(2)delta(2)pi(2) and sigma(2)pi(2)delta(2)delta(2)pi(1) for Ru(3+)(mu-OR)(2)Ru(3+) and Ru(3.5+)(mu-OR)(2)Ru(3.5+), respectively, in which the former is diamagnetic and the latter is paramagnetic with S = (1)/(2) ground state. Compound 5 forms a one-dimensional chain with alternating arrangement of a Ru(3.5+)(mu-OMe)(2)Ru(3.5+) unit and a free benzo-15-crown-5-ether molecule by intermolecular hydrogen bonds (O(H(2)O).O(crown-ether) = 2.91-3.04 A). The cyclic voltammetry in DMF affords characteristic metal-origin voltammograms; two reversible and two quasi-reversible redox waves were observed. The feature of cyclic voltammograms for the Ru(3+)(mu-OR)(2)Ru(3+) species (2, 3, and 6) and the Ru(3.5+)(mu-OR)(2)Ru(3.5+) species (4 and 7) are similar to each other, indicating that both species are electrochemically stable. The isolation of the pyrazine-trans-coordinated species, [Ph(4)P][Ru(Cl(4)Cat)(2)(L)(2)] (L = pyrazine (8), 2,5-dimethylpyrazine (9)), revealed the selective isolation of 6 from pyrazine-containing solution. UV-vis spectral variation by ethanolysis for 9 demonstrated the selective conversion from the pyrazine-trans-coordinated species to the Ru(3+)(mu-OEt)(2)Ru(3+) species without an oxidation to the Ru(3.5+)(mu-OEt)(2)Ru(3.5+) species. This result suggests the presence of equilibrium between [Ru(Cl(4)Cat)(2)(L)(2)](-) and Ru(3+)(mu-OEt)(2)Ru(3+) species in the synthetic condition for 6.

Journal Article↗
PubMed2001

Modulation of the expression of peroxisome proliferator-activated receptor-dependent genes through disproportional expression of two subtypes in the small intestine.

We have reported that dietary long-chain triacylglycerols (LCT) enhance the transcription of cellular retinol-binding protein, the type II (CRBPII) gene, and the liver-type fatty acid-binding protein (L-FABP) gene in the small intestine. Because the cis elements on the CRBPII gene consisting of two AGGTCA motifs separated by a single nucleotide are known to bind not only the 9-cis-retinoic acid receptor (RXR) homodimer, but also the peroxisome proliferator-activated receptor (PPAR)-RXR heterodimer, it has been implicated that the unsaturated long-chain fatty acids, as the ligands of the PPAR, might activate the transcription of the CRBPII gene, thereby making use of the RXR-response elements (RXRE and RE3) as the PPAR-response element (PPRE). In this study, we found that the PPARalpha mRNA level in the rat jejunum was elevated by dietary fat, whereas the PPARdelta mRNA level was reduced under this condition. Electrophoretic mobility-shift assay revealed that both PPARalpha-RXRalpha and PPARdelta-RXRalpha heterodimers, specifically and in a dose-dependent manner, bound to the two PPRE-like elements of the rat CRBPII gene as well as the known PPREs in the L-FABP and acyl-CoA oxidase genes. The binding of the PPARalpha-RXRalpha heterodimer to the CRBPII-RXRE, the CRBPII-RE3, and the PPREs of L-FABP, HMG-CoA synthase, and acyl-CoA oxidase was gradually diminished by the addition of increasing amounts of PPARdelta. The binding of the PPARdelta-RXRalpha heterodimer to CRBPII-RXRE, CRBPII-RE3, and other PPREs was also gradually reduced by the addition of increasing amounts of PPARalpha. Using Escherichia coli-expressed RXRalpha, we showed that the mutual competition for RXRalpha with PPARalpha and PPARdelta occurred at the protein level. These results suggest that the transcriptions of CRBPII, L-FABP, and the other PPAR-dependent genes in the small intestine may be coordinately regulated by the disproportional expression of PPARalpha and PPARdelta.

Animals↗
PubMed2001

The expression of PPAR-associated genes is modulated through postnatal development of PPAR subtypes in the small intestine.

In this study, we found that the mRNA level of peroxisome proliferator-activated receptor (PPAR) alpha, but not of PPARdelta, was elevated in the jejunum during the postnatal development of the rat. Moreover, we found that the expressions of PPAR-dependent genes, such as acyl-CoA oxidase, L-FABP, and I-FABP, were also increased during the postnatal development of the small intestine. Electrophoretic mobility shift assay revealed that both the PPARalpha-9-cis-retinoic acid receptor alpha (RXRalpha) heterodimer and the PPARdelta-RXRalpha heterodimer bound to the peroxisome proliferator response element (PPRE) of acyl-CoA oxidase and L-FABP genes. The binding of the PPARalpha-RXRalpha heterodimer to the PPREs of the various genes was enhanced by the addition of PPARalpha, with a concomitant reduction of the binding of PPARdelta-RXRalpha to the PPREs. Furthermore, the binding activity of PPARalpha-RXRalpha, but not PPARdelta-RXRalpha, to the PPREs was enhanced by the addition of a PPAR ligand, WY14,643. The GAL4-PPAR-chimera reporter assay showed that WY14,643 transactivated the reporter gene through action of PPARalpha, but not through PPARdelta, in Caco-2 cells. Furthermore, oral administration of a PPAR ligand, clofibrate, during 3 consecutive days of the weanling period caused a parallel increase in the mRNA levels of these PPAR-dependent genes. These results suggest that acyl-CoA oxidase, L-FABP and the other PPAR-dependent genes in the small intestine may be coordinately modulated during postnatal development by the disproportional expression of PPARalpha over PPARdelta.

Acyl-CoA Oxidase↗
PubMed2001

Immunoglobulin D myeloma presenting as an extraosseous soft tissue tumor.

We report a 69-year-old man who suffered an extraosseous tumor of immunoglobulin D myeloma (lambda type) in the shoulder girdle, mimicking a primary soft tissue sarcoma. The tumor was isointense with adjacent muscle on T1-weighted MR images, and hyperintense on T2-weighted images. No continuity with the neighboring bone was noted. After administration of gadolinium, the central part of the tumor showed marked contrast enhancement. Although the tumor showed a complete response to the initial chemotherapy, the patient died of the disease 31 months after its initial manifestation. Several bone marrow aspirations and biopsies of the ilium and sternum had shown no increase in plasma cells (range 0.6-1.2%) until the disease became advanced 19 months after its initial manifestation.

Aged↗
PubMed2001

Increase of R5 HIV-1 infection and CCR5 expression in T cells treated with high concentrations of CXCR4 antagonists and SDF-1.

The chemokine receptors CXCR4 and CCR5 are considered to be potential targets for the inhibition of HIV-1 replication. We found that the synthetic peptides T134 and T140 (see text for full names) inhibited X4 HIV-1 infection with selectivity and low toxicity because they acted as CXCR4 antagonists. However, high concentrations of T134, T140, and ALX40-4C (see text for full name) increased the expression of CCR5 and R5 HIV-1 infection, as did stromal cell-derived factor 1 (SDF-1). In contrast to CXCR4 antagonists and SDF-1, viral monocyte inflammatory protein (vMIP) II inhibited not only anti-CXCR4 monoclonal antibody (MAb) but also inhibited anti-CCR5 MAb binding to human peripheral blood mononuclear cells, and inhibited both X4 and R5 HIV-1 strains. T134, T140, ALX40-4C, and SDF-1 increased viral transcription in the treated cells. In addition, ALX40-4C and SDF-1 also increased nuclear transcription factor (NF)-kappaB. However, the mechanisms of action of T134 and T140 are different from those of clinically used anti-HIV drugs. Thus, synergistic activities were observed in the concomitant treatment with T134 and reverse transcriptase inhibitors or protease inhibitors. Our findings, presented here, are noteworthy in regard to the potential clinical use of these agents as drugs for the treatment of AIDS.

Animals↗
PubMed2001

Generation of hepatitis C virus-specific cytotoxic T lymphocytes from healthy individuals with peptide-pulsed dendritic cells.

BACKGROUND AND AIMS: In hepatitis C virus (HCV) infection, cytotoxic T lymphocytes (CTL) are involved in liver inflammation and contribute to the reduction of viral load. Antibodies for HCV-CTL precursor frequencies (CTLpf) are relatively low in chronic hepatitis C, and this may be related to the poor CTL response in vivo. The aim of this study was to assess the efficacy of dendritic cells (DC) as antigen-presenting cells in CTL generation from low CTLpf. METHODS: To confirm the rationale of using DC to prime naive T cells, five HCV-uninfected individuals were enrolled in the study. We obtained DC by maturation from peripheral progenitors under stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-4 and IL-1alpha. Autologous T cells were cultured with DC or concanavalin-A-induced blasts loaded with four HCV-derived peptides bearing human leukocyte antigen (HLA)-A*0201 or -A24 motifs for 28 days under IL-7 and IL-2 stimulation. The lytic activity against peptide-pulsed targets was assessed by using a [51Cr]-releasing assay. RESULTS: The DC strongly expressed HLA class I, II, B7-1 and B7-2, but not phenotypic markers of T-, B-, natural killer (NK)-cells or monocytes. The CD8-positive, HLA-class I-restricted and HCV peptide-specific CTL were generated with DC from HLA-A antigen-matched subjects, whereas no CTL activity was detected with concavalin (Con-A) blasts. We were thus able to generate HCV specific CTL from naive precursors with peptide-pulsed DC. CONCLUSIONS: This DC-based system can be used to generate CTL of desired antigen specificity, even from a source with low CTLpf.

Adult↗
PubMed2001

Imaging evaluation of the cirrhotic liver.

Because recent advances in medical care decrease the mortality rate due to liver cirrhosis itself, many cirrhotic patients die due to hepatocellular carcinoma. Accordingly, the role of radiology in the evaluation of the patient with cirrhosis is primarily to characterize the morphologic manifestations of the disease, evaluate the hepatic and extrahepatic vasculature, assess the effects of portal hypertension, and detect hepatic tumors. When the latter are identified, a critical role of imaging technology is to differentiate hepatocellular carcinoma from other nodular lesions, such as dysplastic nodules and regenerating nodules. Screening strategies for patients with cirrhosis have been proposed to facilitate the detection of small, asymptomatic hepatocellular carcinomas. Dynamic studies using computed tomography (CT) and magnetic resonance imaging (MRI) are very useful for the diagnosis of hepatic tumors previously detected by ultrasound, as well as for screening. In Japan, patients with documented cirrhosis typically undergo serum alpha-fetoprotein testing and/or PIVKA-II (protein induced by vitamin K absence or antagonist II) measurements every 2 months, ultrasound every 3 months, and CT or MRI every 6 months. This has resulted in great success in detecting small hepatocellular carcinomas (less than 2 cm in diameter) and early-stage well-differentiated hepatocellular carcinomas.

Biomarkers↗
PubMed2001

Purification, characterization, and genetic analysis of Cu-containing dissimilatory nitrite reductase from a denitrifying halophilic archaeon, Haloarcula marismortui.

Cu-containing dissimilatory nitrite reductase (CuNiR) was purified from denitrifying cells of a halophilic archaeon, Haloarcula marismortui. The purified CuNiR appeared blue in the oxidized state, possessing absorption peaks at 600 and 465 nm in the visible region. Electron paramagnetic resonance spectroscopy suggested the presence of type 1 Cu (g(II) = 2.232; A(II) = 4.4 mT) and type 2 Cu centers (g(II) = 2.304; A(II) = 13.3 mT) in the enzyme. The enzyme contained two subunits, whose apparent molecular masses were 46 and 42 kDa, according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. N-terminal amino acid sequence analysis indicated that the two subunits were identical, except that the 46-kDa subunit was 16 amino acid residues longer than the 42-kDa subunit in the N-terminal region. A nirK gene encoding the CuNiR was cloned and sequenced, and the deduced amino acid sequence with a residual length of 361 amino acids was homologous (30 to 41%) with bacterial counterparts. Cu-liganding residues His-133, Cys-174, His-182, and Met-187 (for type 1 Cu) and His-138, His-173, and His-332 (for type 2 Cu) were conserved in the enzyme. As generally observed in the halobacterial enzymes, the enzymatic activity of the purified CuNiR was enhanced during increasing salt concentration and reached its maximum in the presence of 2 M NaCl with the value of 960 microM NO(2)(-) x min(-1) x mg(-1).

Absorption↗
PubMed2000

The management of pelvic chondrosarcoma in Japan. Japanese Musculo-Skeletal Oncology Group.

A review of 135 patients with pelvic chondrosarcoma who had been treated at 58 institutions in Japan between 1989 and 1998. In this series ablative surgery was necessary in 14 patients, and a limb salvage procedure performed in 121 patients. The surgical margins were "intra-lesional" in 27 patients, "marginal" in 30, "wide" in 77 and "unspecified" in 1. Local recurrence occurred in 33 patients and distant metastases in 25. Post-operative infection occurred in 25 patients. Revision was performed in 10 patients. The oncological outcome was "disease free" in 92 patients, "alive with disease" in 17 and "dead because of the disease" in 26. The cumulative prospective 10-year survival rate for all patients was 65%. The 6 statistically significant prognostic factors that determined the outcome were: - surgical stage, site of tumour, size of tumour, surgical margin, functional mobility and activity level after surgery. Excision of the tumour with a wide margin, or with a wide margin with partly marginal areas, and subsequent stable reconstruction are essential for improving the results of pelvic chondrosarcoma treatment.

Acetabulum↗
PubMed2000

Expression and evolutionary conservation of nanos-related genes in Hydra.

The Drosophila gene nanos encodes two particular zinc finger motifs which are also found in germline-associated factors from nematodes to vertebrates. We cloned two nanos (nos)-related genes, Cnnos1 and Cnnos2 from Hydra magnipapillata. Using whole-mount in situ hybridization, the expression of Cnnos1 and Cnnos2 was examined. Cnnos1 was specifically expressed in multipotent stem cells and germline cells, but not in somatic cells. Cnnos2 was weakly expressed in germline cells and more specifically in the endoderm of the hypostome where it appears to be involved in head morphogenesis. In addition to structural conservation in the zinc finger domain of nanos-related genes, functional conservation of Cnnos1 was also demonstrated by the finding that a Cnnos1 transgene can partially rescue the nosRC phenotype that is defective in the egg production of Drosophila. Thus, the function of nanos-related genes in the germline appears to be well conserved from primitive to highly evolved metazoans.

Amino Acid Sequence↗
PubMed2000

Effect of salmon calcitonin on experimental osteoporosis induced by ovariectomy and low-calcium diet in the rat.

To investigate the action and effect of calcitonin on osteoporosis, this study was performed in osteoporotic rats that had been ovariectomized and maintained on a low-calcium diet. Significant bone loss was noted in ovariectomized rats compared with those that underwent sham surgeries, and histological findings proved bone turnover to be increased. In comparison with this osteoporotic rat group, those given calcitonin showed less bone loss; the reduction in bone loss was obvious in the vertebral body, and rats given a high dose of calcitonin over a long duration showed even less bone loss, but this was hardly seen in the proximal tibial metaphysis. Histological findings proved that calcitonin inhibited the bone resorption that was stimulated by the ovariectomy. Values for osteoblast surfaces were relatively higher while those of reversal surfaces were lower. The results confirm that salmon calcitonin has an inhibitory action on bone resorption as well as being effective in maintaining and stimulating bone formation in vivo. These effects of calcitonin prevented progress of the osteoporosis that had been induced by ovariectomy, and the effects appeared differently in each region.

Aging↗
PubMed2000

Seventeen-year follow-up of massive osteolysis of the scapula.

A 14-year-old boy with massive osteolysis of the right scapula was treated by irradiation with a total dose of 58 Gy, using cobalt 60 (2 Gy per fraction) in 1983 and 1984. Histopathology in a biopsy specimen revealed hemangiomatosis associated with few osteoclasts and a lining of oval or spindle-shaped endothelial-like cells. The osteolysis has been interrupted since the last irradiation. In January 2000, 17 years after the initial treatment, the patient is working as a public officer, and shows no clinical signs of postradiation sarcoma. Radiographs show a residual scapula with sclerotic margin, associated with marked hypoplasia and atrophy of the right humerus. Ranges of motion of the right shoulder are 100 degrees on anterior elevation, 40 degrees on posterior elevation, and 70 degrees on abduction. The patient experiences no problems in daily living, except for difficulty in lifting.

Adolescent↗
PubMed2000

Clinical characteristics of patients with chronic hepatitis C showing biochemical remission, without hepatitis C virus eradication, as a result of interferon therapy. The Osaka Liver Disease Study Group.

During long-term follow-up of patients chronically infected with the hepatitis C virus (HCV) and treated with interferon (IFN), we identified some who had persistent normalization of serum alanine aminotransferase (ALT) but remained positive for HCV RNA. The aims of this study were to clarify the characteristics of these patients and to examine their clinical outcome after treatment. Nine hundred and ninety-eight patients treated with IFN were followed-up biochemically and virologically, and by liver ultrasound, for 13-95 months. A short-term biochemical sustained response, where ALT remained within the normal range for 6 months after the completion of IFN therapy, was found in 296 patients; in 240 of these patients serum HCV RNA remained undetectable during long-term follow-up. The rate of HCV RNA persistence was 7.09 times greater in short-term biochemical sustained responders with a high viral load than in those with a low viral load (P=0.0001, odds ratio [OR]=7.09), and 3. 70-fold lower in those treated with a large dose of IFN than in those treated with a small dose (P=0.02, OR=0.27). Thirty-three (59%) of 56 patients without HCV eradication showed continuous ALT normalization for 26-80 months after cessation of IFN therapy. Short-term biochemical sustained responders who were older (P=0.009, OR=10.43) and who were male (P=0.03, OR=6.98) had a significantly greater probability of maintaining a normal ALT level, even when serum HCV RNA was positive. When the incidence of HCC was investigated during long-term follow-up in patients without HCV eradication, it was found to be significantly lower in patients with persistently normal ALT levels than in those with abnormal ALT levels (P=0.03). Hence, when HCV is not eradicated as a result of IFN therapy, it may induce a long-term carrier state of HCV infection with normal ALT levels in older or male patients, in whom the cumulative incidence of HCC is markedly decreased.

Adult↗
PubMed2000

Probability of hepatocellular carcinoma of small hepatocellular nodules undetectable by computed tomography during arterial portography.

Recent advances in imaging modalities enable the identification of small hepatocellular nodules. Among the imaging techniques currently used for detecting hepatocellular carcinomas (HCC), computed tomography (CT) during arterial portography (CTAP) is one of the most sensitive techniques available for detecting hemodynamic change. Even so, well-differentiated HCCs that display only limited hemodynamic change, a feature shared with nonmalignant hepatocellular nodules, are not always detectable by CTAP. To improve our ability to distinguish well-differentiated HCCs from nonmalignant hepatocellular nodules, we have attempted to clarify how the characteristics of the nodules are shown by each imaging technique. We studied the imaging and pathological characteristics of 31 nodules (in 22 patients) detected by ultrasonography (US), but not by CTAP. Histological diagnoses were as follows: HCC, 17 of 31 nodules (55%); high-grade dysplastic nodules, 1 of 31 (3%); and nonmalignant nodules, 13 of 31 (42%). Neither digital substraction angiography (DSA) nor CT arteriography (CTA) were able to detect any of the nodules. Detection rates for plain CT were: 5 of 17 (29%) HCC, 1 of 1 (100%) high-grade dysplastic nodules, and 1 of 13 (8%) nonmalignant nodules. Detection rates for T1/T2-weighted magnetic resonance imaging (MRI) were: 4 of 17 (24%) HCC, 1 of 1 (100%) high-grade dysplastic nodules, and 3 of 13 (23%) nonmalignant nodules. Dynamic CT and dynamic MRI provided no additional information. In conclusion, there is some probability that hepatocellular nodules detected by US, but not by CTAP, are HCC. Presently, it is difficult to distinguish between benign nodules and malignant ones with these imaging techniques, and our findings indicate that biopsy may be advisable for nodules detected under these conditions.

Adult↗
PubMed2000

Synthesis of 2,2,4,4-tetramethyl-N,N'-bis(2,6-dimethylphenyl)cyclobutane-1,3-diimine , a unique compound from Arundo donax, and its analogues to test their antifeedant activity against the boll weevil, Anthonomus grandis.

2,2,4,4-Tetramethyl-N,N'-bis(2,6-dimethylphenyl) cyclobutane-1,3-diimine (1), which was isolated from the Thai plant Arundo donax as an antifeedant against the boll weevil (Anthonomus grandis), and its analogues (9-13) were synthesized and shown to possess no remarkable antifeedant activity of practical interest.

Animals↗
PubMed1999

Transcriptional regulation of cellular retinol-binding protein, type II gene expression in small intestine by dietary fat.

We have previously demonstrated that dietary fat, especially unsaturated fatty acids, induces cellular retinol-binding protein, type II (CRBPII) gene expression in rat jejunum. In the present study, we showed that feeding a high-fat diet caused parallel increases in jejunal CRBPII mRNA and CRBPII pre-mRNA levels. Nuclear run-on assay also revealed that this increase of CRBPII mRNA level by high-fat diet was, at least in part, triggered at a transcription level. Moreover, peroxisome proliferator-activated receptor alpha (PPARalpha) mRNA level was also increased in the jejunum by high-fat diet. Gel shift assay showed that the binding activity of rat jejunal nuclear protein to the nuclear receptor response elements located in the rat CRBPII gene (RXRE and RE3) was greater in rats fed high-fat diet than in those fed fat-free diet and were enhanced by addition of bacterially expressed PPARalpha protein. Also PPARalpha-retinoid X receptor alpha (RXRalpha) heterodimer was capable of binding to the CRBPII-RXRE and RE3 elements and these binding activities were enhanced by addition of some PPARalpha ligands in the gel shift assay. Taken together, these studies suggest that dietary fatty acids may lead to induction of CRBPII gene transcription through increases of PPARalpha as well as its ligand levels.

Animals↗
PubMed1999

Purification and characterization of 5-oxo-L-prolinase from Paecilomyces varioti F-1, an ATP-dependent hydrolase active with L-2-oxothiazolidine-4-carboxylic acid.

An enzyme cleaving L-2-oxothiazolidine-4-carboxylic acid to L-cysteine was purified 75-fold with 8% recovery to near homogeneity from crude extracts of Paecilomyces varioti F-1, which had been isolated as a fungus able to assimilate L-2-oxothiazolidine-4-carboxylic acid. The molecular mass was estimated to be 260 kDa by gel filtration. The purified preparation migrated as a single band of molecular mass 140 kDa upon SDS-PAGE. The maximum activity was observed at a range of pH 7.0-8.0 and at 50 degrees C. The enzyme activity was completely inhibited by SH-blocking reagents such as AgNO(3), p-chloromercuribenzoic acid, N-ethylmaleimide, and N-bromosuccinimide. The enzyme required ATP, Mg(2+), and KCl for the cleavage of L-2-oxothiazolidine-4-carboxylic acid. The enzyme also cleaved 5-oxo-L-proline to L-glutamic acid and is considered to be 5-oxo-L-prolinase.

Amidohydrolases↗