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1.
Epidemiol Infect ; 149: e244, 2021 11 02.
Article in English | MEDLINE | ID: mdl-34726137

ABSTRACT

In June 2020, a large-scale food poisoning outbreak involving about 3000 elementary and junior high school students occurred in Yashio, Saitama, Japan. A school lunch was the only food stuff ingested by all of the patients. Escherichia coli serotype O7:H4 carrying the astA gene for enteroaggregative E. coli (EAggEC) heat-stable enterotoxin 1 (EAST1) was detected in faecal specimens from the patients, and sample inspection revealed its presence in a seaweed salad and red seaweed (Gigartina tenella) as one of the raw materials. Analysis of the antibiotic sensitivity of the isolates revealed resistance to ampicillin and cefotaxime. All isolates were confirmed to be of the same origin by pulsed-field gel electrophoresis after digestion with the restriction enzyme XbaI, and single nucleotide polymorphism analysis using whole genome sequencing. To our knowledge, this is the first report of a large-scale food poisoning caused by E. coli O7:H4, which lacks well-characterized virulence genes other than astA.


Subject(s)
Disease Outbreaks , Escherichia coli/isolation & purification , Foodborne Diseases/epidemiology , Foodborne Diseases/microbiology , Bacterial Toxins/genetics , Bacterial Toxins/isolation & purification , DNA, Bacterial/genetics , Drug Resistance, Bacterial , Enterotoxins/genetics , Enterotoxins/isolation & purification , Escherichia coli/genetics , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli Proteins/genetics , Escherichia coli Proteins/isolation & purification , Food Contamination , Food Services , Foodborne Diseases/etiology , Humans , Japan/epidemiology , Rhodophyta , Whole Genome Sequencing
2.
Osteoporos Int ; 26(3): 1093-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25323436

ABSTRACT

UNLABELLED: The associations between mid-femoral cross-sectional geometry and exercise characteristics were investigated in female athletes. The effects on bone geometry for weight-bearing sports with low-to-high-impact were greater than those for non-impact weight-bearing sports, whereas low-impact or high-strain-magnitude/low-strain-rate sports had less of an effect on bone geometry compared with higher-impact sports. INTRODUCTION: Many previous studies have investigated tibial geometry in athletes; however, few studies have examined the associations between femoral cross-sectional geometry and exercise characteristics. The aim of this study was to investigate these relationships using magnetic resonance imaging (MRI) at the femoral mid-shaft. METHODS: One hundred and fifty-three female elite athletes, aged 18-34 years, were classified into five groups based on the characteristics of their sports. Sports were considered non-impact (n = 27), low- or moderate-impact (n = 39), odd-impact (n = 38), high-strain-magnitude/low-strain-rate (n = 10), or high-impact (n = 39). Bone geometrical parameters, including cortical area, periosteal perimeter, and moment of inertia (bone strength index), were determined using MRI images. RESULTS: Higher-impact groups displayed bone expansion, with significantly greater periosteal perimeters, cortical areas (~37.3%), and minimum moments of inertia (I(min,) ~92.3%) at the mid-femur than non- and low-impact groups. After adjusting for age, height, and weight, the cortical area and I(min) of the low-impact and high-strain-magnitude/low-strain-rate groups were also significantly greater than those of the non-impact group. CONCLUSIONS: Higher-impact sports with high strain rates stimulated periosteal bone formation and improved bone geometry and strength indices at the femoral mid-shaft. Although our results indicate that weight-bearing sports are beneficial even if they are low impact, the effects of lower-impact or high-strain-magnitude/low-strain-rate sports on bone geometry were less pronounced than the effects of higher-impact sports at the femoral mid-shaft.


Subject(s)
Athletes , Exercise , Femur , Sports , Adolescent , Adult , Female , Femur/anatomy & histology , Femur/physiology , Humans , Magnetic Resonance Imaging/methods , Weight-Bearing , Young Adult
3.
Pharmacogenomics J ; 13(1): 52-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-21987091

ABSTRACT

Functional single-nucleotide polymorphisms (SNPs) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) (rs28493229) and caspase-3 (CASP3) (rs113420705; formerly rs72689236) are associated with susceptibility to Kawasaki's disease (KD). To evaluate the involvement of these 2 SNPs in the risk for intravenous immunoglobulin (IVIG) unresponsiveness, we investigated 204 Japanese KD patients who received a single IVIG dose of 2 g kg(-1) (n=70) or 1 g kg(-1) daily for 2 days (n=134). The susceptibility allele of both SNPs showed a trend of overrepresentation in IVIG non-responders and, in combined analysis of these SNPs, patients with at least 1 susceptible allele at both loci had a higher risk for IVIG unresponsiveness (P=0.0014). In 335 prospectively collected KD patients who were treated with IVIG (2 g kg(-1)), this 2-locus model showed a more significant association with resistance to initial and additional IVIG (P=0.011) compared with individual SNPs. We observed a significant association when all KD patients with coronary artery lesions were analyzed with the 2-locus model (P=0.0031). Our findings strongly suggest the existence of genetic factors affecting patients' responses to treatment and the risk for cardiac complications, and provide clues toward understanding the pathophysiology of KD inflammation.


Subject(s)
Caspase 3/genetics , Coronary Vessels/pathology , Immunoglobulins, Intravenous/administration & dosage , Mucocutaneous Lymph Node Syndrome/genetics , Mucocutaneous Lymph Node Syndrome/pathology , Phosphotransferases (Alcohol Group Acceptor)/genetics , Alleles , Asian People/genetics , Child , Coronary Vessels/enzymology , Drug Resistance , Female , Genetic Predisposition to Disease , Genotype , Humans , Infant , Infant, Newborn , Male , Mucocutaneous Lymph Node Syndrome/enzymology , Polymorphism, Single Nucleotide , Prospective Studies
5.
J Frailty Aging ; 12(3): 208-213, 2023.
Article in English | MEDLINE | ID: mdl-37493381

ABSTRACT

BACKGROUND: In older people, frailty has been recognized as an important prognostic factor. However, only a few studies have focused on multidimensional frailty as a predictor of mortality and readmission among inpatients with pneumonia. OBJECTIVE: The present study aimed to assess the association between preadmission frailty and clinical outcomes after the hospitalization of older patients with pneumonia. DESIGN: Single-center, retrospective case-control study. SETTING: Acute phase hospital at Kobe, Japan. PARTICIPANTS: The present study included 654 consecutive older inpatients with pneumonia. MEASUREMENTS: Frailty status before admission was assessed using total Kihon Checklist (KCL) score, which has been used as a self-administered questionnaire to assess comprehensive frailty, including physical, social, and cognitive status. The primary outcome was a composited 6-month mortality and readmission after discharge. RESULTS: In total, 330 patients were analyzed (median age: 79 years, male: 70.4%, median total KCL score: 10 points), of which 68 were readmitted and 10 died within 6 months. After multivariate analysis, total KCL score was associated with a composited 6-month mortality and readmission (adjusted hazard ratio, 1.07; 95% confidence interval, 1.02-1.12; p = 0.006). The cutoff value for total KCL score determined by receiver operating characteristic curve analysis was 15 points (area under the curve = 0.610). The group with a total KCL score ≥ 15 points had significantly higher readmission or mortality rates than the groups with a total KCL score < 15 points (p < 0.001). CONCLUSIONS: Preadmission frailty status in older patients with pneumonia was an independent risk factor for readmission and survival after hospitalization.


Subject(s)
Frailty , Pneumonia , Humans , Male , Aged , Frailty/diagnosis , Frail Elderly , Patient Readmission , Retrospective Studies , Case-Control Studies , Geriatric Assessment/methods
6.
J Asthma ; 49(3): 288-93, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22356355

ABSTRACT

OBJECTIVE: To assess the impact of omalizumab as an add-on therapy to standard treatment with inhaled corticosteroids (ICS) and long-acting beta-2 agonists (LABA) on asthma-related quality of life (QoL) in patients with severe allergic asthma. METHODS: This was a 20-week, randomized, open-label, study involving Brazilian patients (>12 years) with severe persistent allergic asthma inadequately controlled despite regular treatment with, at least, ICS (≥500 µg/day fluticasone or equivalent) + LABA. The primary objective was to assess the mean change from baseline in overall Asthma-related Quality of Life Questionnaire (AQLQ) score in omalizumab-treated patients compared with the control group. Secondary outcome measures included rescue medication use, incidence of asthma exacerbations, perception of treatment efficacy among patients, mean change from baseline in AQLQ score, and >1.5-point increase in overall AQLQ score. RESULTS: In the omalizumab group, overall AQLQ score was 3.2 (0.9) (mean [SD]) at baseline and 4.4 (1.3) at week 20 versus 3.0 (1.0) at baseline and 3.0 (1.1) at week 20 in the control group. Mean change from baseline on overall AQLQ score at week 20 in the omalizumab group was 1.2 (0.2) versus 0 (0.1) in the control group, showing a significant increase in scores from baseline in the omalizumab group (p < .001). There was also a statistically significant difference (p < .001) in the number of patients who showed a >1.5-point increase from baseline in overall AQLQ score after 20 weeks, thus indicating a better QoL in the omalizumab group. There was no significant difference with respect to the use of rescue medication, incidence of asthma exacerbation, and adverse events between treatment groups. The global evaluation of treatment effectiveness was significantly better for omalizumab (p < .001). CONCLUSION: Omalizumab was well tolerated and significantly improved the overall AQLQ score. Hence, it is a potential add-on therapy for severe persistent allergic asthma not controlled by standard prescribed treatment in Brazilian patients.


Subject(s)
Antibodies, Anti-Idiotypic/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Asthma/drug therapy , Quality of Life , Adolescent , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/therapeutic use , Adrenergic beta-2 Receptor Antagonists/administration & dosage , Adrenergic beta-2 Receptor Antagonists/therapeutic use , Adult , Aged , Anti-Asthmatic Agents/adverse effects , Anti-Asthmatic Agents/therapeutic use , Antibodies, Anti-Idiotypic/administration & dosage , Antibodies, Anti-Idiotypic/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Asthma/complications , Asthma/physiopathology , Brazil/epidemiology , Drug Hypersensitivity/complications , Drug Hypersensitivity/epidemiology , Drug Therapy, Combination/methods , Female , Food Hypersensitivity/complications , Food Hypersensitivity/epidemiology , Forced Expiratory Volume/physiology , Humans , Immunoglobulin E/blood , Male , Middle Aged , Omalizumab , Racial Groups/statistics & numerical data , Rhinitis, Allergic, Seasonal/complications , Rhinitis, Allergic, Seasonal/epidemiology , Treatment Outcome , Young Adult
7.
Arch Virol ; 155(4): 455-62, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20127373

ABSTRACT

ErbB3 binding protein Ebp1 has been shown to downregulate ErbB3 receptor-mediated signaling to inhibit cell proliferation. Rinderpest virus belongs to the family Paramyxoviridae and is characterized by the presence of a non-segmented negative-sense RNA genome. In this work, we show that rinderpest virus infection of Vero cells leads to the down-regulation of the host factor Ebp1, at both the mRNA and protein levels. Ebp1 protein has been shown to co-localize with viral inclusion bodies in infected cells, and it is packaged into virions, presumably through its interaction with the N protein or the N-RNA itself. Overexpression of Ebp1 inhibits viral transcription and multiplication in infected cells, suggesting that a mutual antagonism operates between host factor Ebp1 and the virus.


Subject(s)
Adaptor Proteins, Signal Transducing/biosynthesis , Down-Regulation , Gene Expression , Rinderpest virus/pathogenicity , Animals , Chlorocebus aethiops , Vero Cells
9.
Phytopathology ; 99(4): 369-77, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19271978

ABSTRACT

The tangerine pathotype of Alternaria alternata produces host-selective ACT-toxin and causes Alternaria brown spot disease. Sequence analysis of a genomic cosmid clone identified a part of the ACTT gene cluster and implicated two genes, ACTT5 encoding an acyl-CoA synthetase and ACTT6 encoding an enoyl-CoA hydratase, in the biosynthesis of ACT-toxin. Genomic Southern blots demonstrated that both genes were present in tangerine pathotype isolates producing ACT-toxin and also in Japanese pear pathotype isolates producing AK-toxin and strawberry pathotype isolates producing AF-toxin. ACT-, AK-, and AF-toxins from these three pathotypes share a common 9,10-epoxy-8-hydroxy-9-methyl-decatrienoic acid moiety. Targeted gene disruption of two copies of ACTT5 significantly reduced ACT-toxin production and virulence. Targeted gene disruption of two copies of ACTT6 led to complete loss of ACT-toxin production and pathogenicity and a putative decatrienoic acid intermediate in ACT-toxin biosynthesis accumulated in mycelial mats. These results indicate that ACTT5 and ACTT6 are essential genes in ACT-toxin biosynthesis in the tangerine pathotype of A. alternata and both are required for full virulence of this fungus.


Subject(s)
Alternaria/genetics , Coenzyme A Ligases/genetics , Enoyl-CoA Hydratase/genetics , Mycotoxins/biosynthesis , Alternaria/enzymology , Alternaria/pathogenicity , Citrus/microbiology , Genes, Fungal , Genomics , Host-Pathogen Interactions/genetics , Virulence
10.
Br J Sports Med ; 43(12): 932-5, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19124528

ABSTRACT

OBJECTIVE: To investigate whether childhood sports participation, particularly weight-bearing sports, has any effect on bone mineral content (BMC), areal bone mineral density (aBMD) and bone geometric characteristics in middle-aged postmenopausal women. Design/ SETTING: In this cross-sectional comparison of two groups, 46 middle-aged women (mean age, 60.2 (SD 5.6) years; range, 52-73 years) were grouped according to sport participation during growth: weight-bearing sports, including high-impact weight-bearing activities; and low-impact non-weight-bearing sports or no participation. MAIN OUTCOME MEASURES: Dual energy X-ray absorptiometry (DXA)-measured BMC, aBMD in the lumbar spine and femur. Magnetic resonance imaging (MRI) determined bone geometric characteristics in the femur, such as femoral mid-diaphyseal cross-sectional area, periosteal and endosteal perimeters and maximum and minimum second moment of area. RESULTS: Postmenopausal middle-aged women with participation in weight-bearing sports during junior high to high school (12-18 years old) displayed significantly greater BMC in both lumbar spine and femoral neck regions, and also significantly greater femoral mid-diaphyseal bone cross-sectional area, periosteal perimeter and maximum and minimum second moment of area than the non-weight-bearing sports group. CONCLUSIONS: Adolescent weight-bearing exercise exerts preservational effects on femoral mid-diaphyseal size and shape, while DXA-measured BMC effectively identified the same tendency. Weight-bearing exercise in youth affects bone, and these effects may be preserved as BMC, geometric and structural advantages even after 40 years.


Subject(s)
Bone Density/physiology , Exercise/physiology , Osteoporosis, Postmenopausal/pathology , Sports/physiology , Adolescent , Aged , Calcium, Dietary/administration & dosage , Child , Cross-Sectional Studies , Female , Humans , Lumbar Vertebrae , Magnetic Resonance Imaging , Middle Aged , Weight-Bearing/physiology
11.
Rev Sci Instrum ; 79(2 Pt 2): 02A519, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18315140

ABSTRACT

The first long pulse production of high power D(-) ion beams has been demonstrated in the JT-60 U negative ion sources, each of which was designed to produce 22 A, 500 keV D(-) ion beams. Voltage holding capability and the grid power loading were examined for long pulse production of high power D(-) ion beams. From the correlation between voltage holding and the light intensity of cathodoluminescence from the Fiber Reinforced Plastic insulators, the acceleration voltage for stable voltage holding capability was found to be less than 320-340 kV where the light was sufficiently suppressed. By tuning the extraction voltage, the grid power loadings in the ion sources were decreased to the allowable levels for long pulse injection without a significant reduction of the beam power. After tuning the acceleration and extraction voltages, D(-) ion beams of 12.5 and 9.8 A were produced at 340 keV with cesium seeding at a rate of approximately 14 microg/s into the ion sources. The pulse duration of these D(-) ion beams was extended step by step, and then was successfully extended up to 18 s without degradation of the negative ion production. The D(-) ion beams were neutralized to yield 3.6 MW D(0) beams by a gas cell, and then injected into the JT-60 U plasma. Further, a slight reduction of D(-) ion beam power allowed the longer injection duration of 21 s at a D(0) beam power of 3.2 MW. The success in the long pulse production of a high power D(-) ion beam shows that negative ion beams can be produced during a few tens of seconds without degradations of negative ion production and the voltage holding in a large Cs-seeded negative ion source.

12.
J Clin Invest ; 96(4): 1779-85, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7560069

ABSTRACT

We investigated the enzyme defect in late cholesterol biosynthesis in the Smith-Lemli-Opitz syndrome, a recessively inherited developmental disorder characterized by facial dysmorphism, mental retardation, and multiple organ congenital anomalies. Reduced plasma and tissue cholesterol with increased 7-dehydrocholesterol concentrations are biochemical features diagnostic of the inherited enzyme defect. Using isotope incorporation assays, we measured the transformation of the precursors, [3 alpha- 3H]lathosterol and [1,2-3H]7-dehydrocholesterol into cholesterol by liver microsomes from seven controls and four Smith-Lemli-Opitz homozygous subjects. The introduction of the double bond in lathosterol at C-5[6] to form 7-dehydrocholesterol that is catalyzed by lathosterol-5-dehydrogenase was equally rapid in controls and homozygotes liver microsomes (120 +/- 8 vs 100 +/- 7 pmol/mg protein per min, P = NS). In distinction, the reduction of the double bond at C-7 [8] in 7-dehydrocholesterol to yield cholesterol catalyzed by 7-dehydrocholesterol-delta 7-reductase was nine times greater in controls than homozygotes microsomes (365 +/- 23 vs 40 +/- 4 pmol/mg protein per min, P < 0.0001). These results demonstrate that the pathway of lathosterol to cholesterol in human liver includes 7-dehydrocholesterol as a key intermediate. In Smith-Lemli-Opitz homozygotes, the transformation of 7-dehydrocholesterol to cholesterol by hepatic microsomes was blocked although 7-dehydrocholesterol was produced abundantly from lathosterol. Thus, lathosterol 5-dehydrogenase is equally active which indicates that homozygotes liver microsomes are viable. Accordingly, microsomal 7-dehydrocholesterol-delta 7-reductase is inherited abnormally in Smith-Lemli-Opitz homozygotes.


Subject(s)
Microsomes, Liver/enzymology , Oxidoreductases Acting on CH-CH Group Donors , Oxidoreductases/antagonists & inhibitors , Smith-Lemli-Opitz Syndrome/enzymology , Cholesterol/biosynthesis , Cholesterol/metabolism , Female , Homozygote , Humans , Oxidoreductases/metabolism , Smith-Lemli-Opitz Syndrome/genetics
13.
Leukemia ; 31(5): 1136-1144, 2017 05.
Article in English | MEDLINE | ID: mdl-27807369

ABSTRACT

Mutations of calreticulin (CALR) are detected in 25-30% of patients with essential thrombocythemia (ET) or primary myelofibrosis and cause frameshifts that result in proteins with a novel C-terminal. We demonstrate that CALR mutations activated signal transducer and activator of transcription 5 (STAT5) in 293T cells in the presence of thrombopoietin receptor (MPL). Human megakaryocytic CMK11-5 cells and erythroleukemic F-36P-MPL cells with knocked-in CALR mutations showed increased growth and acquisition of cytokine-independent growth, respectively, accompanied by STAT5 phosphorylation. Transgenic mice expressing a human CALR mutation with a 52 bp deletion (CALRdel52-transgenic mice (TG)) developed ET, with an increase in platelet count, but not hemoglobin level or white blood cell count, in association with an increase in bone marrow (BM) mature megakaryocytes. CALRdel52 BM cells did not drive away wild-type (WT) BM cells in in vivo competitive serial transplantation assays, suggesting that the self-renewal capacity of CALRdel52 hematopoietic stem cells (HSCs) was comparable to that of WT HSCs. Therapy with the Janus kinase (JAK) inhibitor ruxolitinib ameliorated the thrombocytosis in TG mice and attenuated the increase in number of BM megakaryocytes and HSCs. Taken together, our study provides a model showing that the C-terminal of mutant CALR activated JAK-STAT signaling specifically downstream of MPL and may have a central role in CALR-induced myeloproliferative neoplasms.


Subject(s)
Calreticulin/genetics , Animals , Cell Self Renewal , HEK293 Cells , Hematopoietic Stem Cells , Humans , Janus Kinases/antagonists & inhibitors , Mice , Mice, Transgenic , Myeloproliferative Disorders/chemically induced , Myeloproliferative Disorders/etiology , Nitriles , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Pyrazoles/pharmacology , Pyrazoles/therapeutic use , Pyrimidines , Receptors, Thrombopoietin , STAT5 Transcription Factor/metabolism , Thrombocythemia, Essential/drug therapy , Thrombocythemia, Essential/genetics
14.
Biochim Biophys Acta ; 1014(3): 305-12, 1989 Dec 14.
Article in English | MEDLINE | ID: mdl-2481503

ABSTRACT

We examined which substances stimulate hyaluronic acid synthesis in rabbit pericardium and pericardial cells. (1) The addition of 10% (v/v) pericardial fluid to the incubation medium of the pericardium enhanced hyaluronic acid synthesis to about 2.5-times over the control, suggesting that there were some stimulating factors of the hyaluronic acid synthesis in the pericardial fluid. (2) The addition of 100 ng/ml insulin-like growth factor-I (IGF-I) to the incubation medium caused an approx. 2-fold increase of hyaluronic acid synthesis over the control in the pericardium. (3) IGF-I stimulated the hyaluronic acid synthesis in pericardial cells in a dose-dependent manner, but did not significantly stimulate the sulfated glycosaminoglycan synthesis. (4) The increase in the hyaluronic acid synthesis induced by IGF-I (100 ng/ml) or pericardial fluid was blocked by the copresence of monoclonal anti-IGF-I antibody. (5) IGF-I caused possible induction of the hyaluronic acid synthase activity and general protein and RNA synthesis before the initiation of DNA synthesis in pericardial cells. These results suggest a new biological action of IGF-I that stimulates hyaluronic acid synthesis in pericardium or the pericardial cavity of heart.


Subject(s)
Glycosyltransferases , Hyaluronic Acid/biosynthesis , Insulin-Like Growth Factor I/pharmacology , Membrane Proteins , Pericardium/drug effects , Somatomedins/pharmacology , Transferases , Xenopus Proteins , Animals , Antibodies, Monoclonal , Cells, Cultured , Chromatography, Gel , DNA/analysis , Dose-Response Relationship, Drug , Exudates and Transudates/metabolism , Glucuronosyltransferase/analysis , Glycosaminoglycans/biosynthesis , Hyaluronan Synthases , Insulin-Like Growth Factor I/immunology , Pericardium/metabolism , Pericardium/physiology , Pronase , RNA/analysis , Rabbits
15.
Biochim Biophys Acta ; 877(3): 423-32, 1986 Jul 18.
Article in English | MEDLINE | ID: mdl-3089289

ABSTRACT

The appearance of the arachidonic acid metabolic pathway in human promyelocytic leukemia (HL-60) cells was investigated during 1 alpha,25-dihydroxyvitamin D-3-induced monocytic differentiation. 1 alpha,25-Dihydroxyvitamin D-3-treated HL-60 cells acquired the ability to convert [1-14C]arachidonic acid to thromboxane B2 and prostaglandin E2 during monocytic differentiation. The major cyclooxygenase product synthesized by the HL-60 cells after 3-4 days exposure to 1 alpha,25- dihydroxyvitamin D-3 (48 nM) was thromboxane B2 and its production was about 19-25-times higher than that of untreated HL-60 cells. The percent conversion of thromboxane B2 from [1-14C]arachidonic acid in the 1 alpha,25-dihydroxyvitamin D-3 (48 nM, 3 day exposure)-treated HL-60 cells was about 4.4% as compared to that (about 0.3%) of the untreated cells, whereas the percent conversion of thromboxane B2 from [1-14C]prostaglandin H2 in the 1 alpha,25-dihydroxyvitamin D-3-treated cell homogenate was about 22.4% as compared to that (about 13.6%) of the untreated cell homogenate. The stimulatory effect of 1 alpha,25-dihydroxyvitamin D-3 on thromboxane B2 production from [1-14C]arachidonic acid and from [1-14C]prostaglandin H2 in HL-60 cells was inhibited by the addition of cycloheximide (1 microgram/ml). However, 1 alpha,25-dihydroxyvitamin D-3 (48 nM) did not significantly stimulate the arachidonic acid release either in HL-60 cells or in 1 alpha,25-dihydroxyvitamin D-3-induced cells. These results suggest that the stimulatory effect of 1 alpha,25-dihydroxyvitamin D-3 on the thromboxane production in HL-60 cells was not due to the activation of phospholipase A2 but due to the induction of fatty acid cyclooxygenase and thromboxane synthetase activities. Thromboxane A2 actively produced during the monocytic differentiation of HL-60 cells could influence the cell adhesiveness of the monocyte-macrophage-differentiated cells.


Subject(s)
Arachidonic Acids/metabolism , Calcitriol/pharmacology , Leukemia, Myeloid, Acute/metabolism , Monocytes/cytology , Thromboxane B2/biosynthesis , Arachidonic Acid , Carbon Radioisotopes , Cell Differentiation/drug effects , Cell Line , Cycloheximide/pharmacology , Dimethyl Sulfoxide/pharmacology , Dose-Response Relationship, Drug , Humans , Leukemia, Myeloid, Acute/pathology , Methacrylates/pharmacology , Prostaglandin Endoperoxides, Synthetic/metabolism , Prostaglandin H2 , Prostaglandins H/metabolism , Time Factors , Tretinoin/pharmacology
16.
Biochim Biophys Acta ; 794(3): 403-10, 1984 Jul 26.
Article in English | MEDLINE | ID: mdl-6430346

ABSTRACT

Minced rabbit pericardium actively converts [1-14C]arachidonic acid into the known prostaglandins (6-[1-14C]ketoprostaglandin F1 alpha, [1-14C]prostaglandin E2 and [1-14C]prostaglandin F2 alpha) and into several unidentified metabolites. The major metabolite was separated by C18 reverse-phase high-pressure liquid chromatography (HPLC) and identified by gas chromatography-mass spectrometry (GC-MS) to be 6,15-[1-14C]diketo-13,14-dihydroprostaglandin F1 alpha. The other nonpolar metabolites were 15-[1-14C]hydroxy-5,8,11,13-eicosa-tetraenoic acid (15-HETE), 11-[1-14C]hydroxy-5,8,12,14-eicosatetraenoic acid (11-HETE) and 12-[1-14C]hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE). Arachidonic acid metabolites actively produced by the pericardium could influence the tone of surface blood vessels on the myocardium.


Subject(s)
Arachidonic Acids/metabolism , Hydroxyeicosatetraenoic Acids , Pericardium/metabolism , 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid , 6-Ketoprostaglandin F1 alpha/analogs & derivatives , 6-Ketoprostaglandin F1 alpha/metabolism , Animals , Arachidonic Acid , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Gas Chromatography-Mass Spectrometry , Rabbits
17.
Biochim Biophys Acta ; 1175(3): 343-50, 1993 Feb 17.
Article in English | MEDLINE | ID: mdl-8382086

ABSTRACT

The functional interaction of prostaglandin E (PGE) receptor EP3 subtype with GTP-binding proteins (G proteins) was characterized in the membranes prepared from mouse EP3 receptor cDNA-transfected Chinese hamster ovary cells. PGE2 inhibited forskolin-stimulated adenylate cyclase activity in CHO cells expressing EP3 receptor and this inhibition was abolished by pertussis toxin (PT) treatment. The PGE2 binding to the membranes was increased by GTP gamma S, and PT treatment also increased the binding activity to the same level as that increased by GTP gamma S, but the sensitivity of GTP gamma S was lost. Reconstitution with PT-sensitive G proteins into the ADP-ribosylated membranes reduced the PGE2 binding activity with the following preference: Gi1 = Gi2 > Gi3 > GO, but GTP gamma S completely blocked the reduction by G proteins. The G-protein-induced reduction of the binding was due to the increase in Kd without the change of Bmax, and due to suppression of association rate. [3H]PGE2-bound EP3 receptor solubilized from the ADP-ribosylated membranes in the presence or absence of GTP gamma S was eluted at the position of M(r) = approx. 60 kDa, similar to the relative molecular mass of EP3 receptor deduced from its amino acid sequence. In contrast, [3H]PGE2-bound receptor solubilized from Gi2-reconstituted membranes was eluted at the position of M(r) = approx. 130 kDa, corresponding to the M(r) of the complex of EP3 receptor and Gi2, but GTP gamma S shifted the position of its elution from M(r) = 130 to 60 kDa. Furthermore, addition of PGE2 stimulated the GDP release from G proteins reconstituted into the ADP-ribosylated membranes, and PGE2 inhibited forskolin-stimulated adenylate cyclase activity in G-protein-reconstituted membranes with a selectivity order of Gi1 = Gi2 > Gi3 > GO. These results indicate that EP3 receptor can functionally couple to PT-sensitive G proteins and unusually the complex form with G proteins has low affinity for the ligand but the form not associated with G proteins has high affinity.


Subject(s)
GTP-Binding Proteins/metabolism , Receptors, Prostaglandin/metabolism , Adenosine Diphosphate/metabolism , Adenylate Cyclase Toxin , Adenylyl Cyclase Inhibitors , Animals , Cell Line , Cricetinae , Cricetulus , Cyclic AMP/biosynthesis , Dinoprostone/pharmacology , Pertussis Toxin , Receptors, Prostaglandin E , Virulence Factors, Bordetella
18.
Biochim Biophys Acta ; 1171(3): 304-6, 1993 Jan 23.
Article in English | MEDLINE | ID: mdl-8381027

ABSTRACT

The primary structure of nucleoside diphosphate (NDP) kinase II, one of the two isozymes found in spinach leaves, has been deduced from its cDNA sequence. NDP kinase II comprises 233 amino acid residues and has a molecular mass of 26,107 Da, which is larger than that of the purified NDP kinase II subunits (18 kDa) by about 8 kDa, suggesting that NDP kinase II might be post-translationally processed. Homology was found between the sequence of spinach NDP kinase II, and the sequences of spinach NDP kinase I, rat NDP kinases alpha and beta, Dictyostelium discoideum NDP kinase, the human Nm23-H1 and Nm23-H2 proteins and the awd protein of Drosophila melanogaster.


Subject(s)
Nucleoside-Diphosphate Kinase/chemistry , Plants, Edible/enzymology , Amino Acid Sequence , Animals , Base Sequence , Dictyostelium/metabolism , Drosophila melanogaster/metabolism , Humans , Molecular Sequence Data , Protein Processing, Post-Translational , Rats , Sequence Homology, Nucleic Acid
19.
Cell Death Differ ; 10(6): 698-708, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12761578

ABSTRACT

The aberrant splicing isoform (PS2V), generated by exon 5 skipping of the Presenilin-2 (PS2) gene transcript, is a diagnostic feature of sporadic Alzheimer's disease (AD). We found PS2V is hypoxia-inducible in human neuroblastoma SK-N-SH cells. We purified a responsible trans-acting factor based on its binding to an exon 5 fragment. The factor was identified as the high mobility group A1a protein (HMGA1a; formerly HMG-I). HMGA1a bound to a specific sequence on exon 5, located upstream of the 5' splice site. HMGA1a expression was induced by hypoxia and the protein was accumulated in the nuclear speckles with the endogenous splicing factor SC35. Overexpression of HMGA1a generated PS2V, but PS2V was repressed by cotransfection with the U1 snRNP 70K protein that has a strong affinity to HMGA1a. HMGA1a could interfere with U1 snRNP binding to the 5' splice site and caused exon 5 skipping. HMGA1a levels were significantly increased in the brain tissue from sporadic AD patients. We propose a novel mechanism of sporadic AD that involves HMGA1a-induced aberrant splicing of PS2 pre-mRNA in the absence of any mutations.


Subject(s)
Alternative Splicing/genetics , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , HMGA1a Protein/metabolism , Membrane Proteins/genetics , RNA Precursors/genetics , Base Sequence/genetics , Binding Sites/genetics , Exons/genetics , Genes, Regulator/genetics , HMGA1a Protein/genetics , Humans , Hypoxia/genetics , Hypoxia/metabolism , Membrane Proteins/biosynthesis , Mutation/genetics , Presenilin-2 , Protein Isoforms/biosynthesis , Protein Isoforms/genetics , RNA Splice Sites/genetics , RNA, Small Nuclear/genetics
20.
J Bone Miner Res ; 16(9): 1688-93, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11547839

ABSTRACT

This study was designed to investigate the effect of high-impact and low-repetition jump training on bones in ovariectomized (OVX) rats. Forty female Wistar rats were sham-operated (sham) or OVX at the age of 11 weeks. The rats were divided randomly into the following four groups: sham-sedentary (SS; n = 10), sham-exercised (SE; n = 10), OVX-sedentary (OS; n = 10), and OVX-exercised (OE; n = 10). The rats started the jump training at the age of 12 weeks. The jump-training protocol was 10 times/day, 5 days/week and the jumping-height was 40 cm. After 8 weeks of training, the mass and breaking force in the tibia and ulna, cross-sectional areas of diaphysis in the tibia, and serum bone turnover markers were measured. The jump training significantly increased the fat-free dry weight, ash weight, and ultimate breaking force in the tibia. The rate of increase in these parameters was similar in both the sham and the OVX groups. On the other hand, in the ulna, there were no significant changes in the ultimate breaking force. The jump training significantly increased the periosteal perimeter and cortical area, although the increase in these parameters in OE compared with OS was lower than that in SE compared with SS. The jump training significantly increased serum osteocalcin in the OVX groups, as well as in the sham groups. These results suggest that high-impact and low-repetition training had beneficial effects on bone formation and bone biomechanical properties in OVX rats, as well as in sham rats.


Subject(s)
Bone and Bones/physiology , Physical Exertion/physiology , Animals , Body Weight , Bone Density , Bone and Bones/metabolism , Collagen/blood , Collagen Type I , Cross-Sectional Studies , Female , Organ Size , Osteocalcin/blood , Osteoporosis/prevention & control , Ovariectomy/adverse effects , Peptides/blood , Rats , Rats, Wistar , Tibia/physiology , Uterus/physiology
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