181 research outputs found
Isolation and amino acid sequence of the 30S ribosomal protein S19 from Mycobacterium bovis BCG
AbstractThe 30S ribosomal proteins from Mycobacterium bovis BCG were separated by reverse phase-high performance liquid chromatography (RP-HPLC). The isolated proteins were analyzed by SDS-PAGE, blotted on PVDF-membranes and subjected to sequence analyses using a gas-phase sequencer to correlate them to those of the well studied Escherichia coli and Bacillus stearothermophilus ribosomes. Moreover, the internal amino acid sequence of one ribosomal protein, MboS19, which is homologous to E. coli ribosomal protein S19 (EcoS19) and B. stearothermophilus ribosomal protein S19 (BstS19), was further analyzed by sequencing its internal peptides and two segments from the N- and C-termini of the protein were selected to deduce the sequence of two oligonucleotide primers which were used in a polymerase chain reaction. Using the amplified DNA fragment thus obtained as a hybridization probe, the gene encoding protein S19 was identified and cloned. Sequence analysis of the DNA fragment, together with peptide sequence analysis could determine the complete amino acid sequence of MboS19. This sequence proved to be 64% and 71% identical to those of the corresponding S19 proteins from the eubacteria E. coli, and B. stearothermophilus, respectively; 33% of the residues of MboS19 were identical to those in the archaebacteral ribosomal protein HmaS19
Development of a Novel Reformer for Tar-free Syngas Production
AbstractA novel reformer using highly efficient heat regeneration for tar-free syngas production is developed and its performance demonstrated in a pilot-scale plant using steam gasification. Basic design parameters of the regenerative tar reformer, namely residence time and amount of oxidant are determined based on numerical results. It has been predicted that good performance could be achieved at an operation temperature about 1573K, the residence time exceeding 4sec and an oxidant addition of 12% of the syngas flow rate. The regenerative tar reformer so designed shows stable operation. Over 99% of light and heavy tars are reformed to gas in the case of 11.3% oxygen addition to syngas. Further it is seen that a reduction of oxygen consumption more than 30% compared to a conventional oxidation reformer can be achieved. The formation of a high temperature zone has a strong influence on the tar reforming efficiency
A Novel Strategy in Production of Oligosaccharides in Digestive Tract: Prevention of Postprandial Hyperglycemia and Hyperinsulinemia
The aim of this study was to evaluate the effects of oral administration of transglucosidase (TG) on postprandial glucose concentrations in healthy subjects. A randomized placebo-controlled three-way crossover trial was separated by a washout period of more than 3 days. Twenty-one normal healthy volunteers, aged 30–61 years old (17 males and 4 females) were selected for this study. The subjects’ health was assessed as normal by prestudy screening. All subjects received 3 types of test meals (3 rice balls: protein, 14.4 g; fat, 2.1 g; and carbohydrate, 111 g: total energy, 522 kcal) with 200 ml water in which 0 mg, 150 mg, or 300 mg of TG was dissolved. Blood samples for estimating plasma glucose and insulin concentrations were collected before and every 30 min after the experiment. As compared to no TG treatment, TG administration tended to prevent a postprandial increase in plasma glucose (p = 0.069: 150 mg of TG vs control) but there were no significant difference among three groups. With regard to the 17 subjects who were suggested to have impaired glucose tolerance, TG significantly decreased the postprandial blood glucose (p<0.05: 150 mg and 300 mg of TG vs control) and marginally decreased insulin concentrations (p = 0.099: 300 mg of TG vs control). These results suggest that TG may be useful for preventing the progression of type 2 diabetes mellitus
Relationship between postprandial glucose level and carotid artery stiffness in patients without diabetes or cardiovascular disease
BACKGROUND: The aim of this study was to evaluate the relationship between postprandial glucose level and atherosclerosis in patients without diabetes and cardiovascular disease by determining carotid ultrasonographic variables and serum levels of 1,5-anhydroglucitol (1,5-AG). METHODS: The subjects were 72 patients without diabetes and cardiovascular disease being treated for hypertension or dyslipidemia. The clinical characteristics of all subjects, including the serum level of 1,5-AG, which appears to be well suited for monitoring postprandial hyperglycemia, were evaluated after an overnight fast. The average intima-media thickness (IMT) and the average pulsatility index (PI) of the right and left common carotid arteries were determined with high-resolution ultrasonography and used as ultrasonographic variables. The subjects were divided into a Lower 1,5-AG group (n = 36) and a Higher 1,5-AG group (n = 36). We evaluated the relationship between clinical characteristics and ultrasonographic variables of the carotid artery in both groups. RESULTS: The average PI in the Lower 1,5-AG group was significantly higher than that in the Higher 1,5-AG group, but the average IMT did not differ between the groups. Linear regression analysis, with the ultrasonographic variables as the dependent variables, with 1,5-AG as the independent variable, and adjusted for other clinical characteristics, showed significant correlation between 1,5-AG and the PI but not between 1,5-AG and IMT. CONCLUSION: Our results suggest that postprandial hyperglycemia increases carotid artery stiffness, but not morphological change, in patients without diabetes or cardiovascular disease
Combination Therapy with a Sodium-Glucose Cotransporter 2 Inhibitor and a Dipeptidyl Peptidase-4 Inhibitor Additively Suppresses Macrophage Foam Cell Formation and Atherosclerosis in Diabetic Mice
Dipeptidyl peptidase-4 inhibitors (DPP-4is), in addition to their antihyperglycemic roles, have antiatherosclerotic effects. We reported that sodium-glucose cotransporter 2 inhibitors (SGLT2is) suppress atherosclerosis in a glucose-dependent manner in diabetic mice. Here, we investigated the effects of combination therapy with SGLT2i and DPP-4i on atherosclerosis in diabetic mice. SGLT2i (ipragliflozin, 1.0 mg/kg/day) and DPP-4i (alogliptin, 8.0 mg/kg/day), either alone or in combination, were administered to db/db mice or streptozotocin-induced diabetic apolipoprotein E-null (Apoe−/−) mice. Ipragliflozin and alogliptin monotherapies improved glucose intolerance; however, combination therapy did not show further improvement. The foam cell formation of peritoneal macrophages was suppressed by both the ipragliflozin and alogliptin monotherapies and was further enhanced by combination therapy. Although foam cell formation was closely associated with HbA1c levels in all groups, DPP-4i alone or the combination group showed further suppression of foam cell formation compared with the control or SGLT2i group at corresponding HbA1c levels. Both ipragliflozin and alogliptin monotherapies decreased scavenger receptors and increased cholesterol efflux regulatory genes in peritoneal macrophages, and combination therapy showed additive changes. In diabetic Apoe−/− mice, combination therapy showed the greatest suppression of plaque volume in the aortic root. In conclusion, combination therapy with SGLT2i and DPP4i synergistically suppresses macrophage foam cell formation and atherosclerosis in diabetic mice
Co-activation of macrophages and T cells contribute to chronic GVHD in human IL-6 transgenic humanised mouse model.
BACKGROUND: Graft-versus host disease (GVHD) is a complication of stem cell transplantation associated with significant morbidity and mortality. Non-specific immune-suppression, the mainstay of treatment, may result in immune-surveillance dysfunction and disease recurrence.
METHODS: We created humanised mice model for chronic GVHD (cGVHD) by injecting cord blood (CB)-derived human CD34
FINDINGS: In cGVHD humanised mice, we found activation of T cells in the spleen, lung, liver, and skin, activation of macrophages in lung and liver, and loss of appendages in skin, obstruction of bronchioles in lung and portal fibrosis in liver recapitulating cGVHD. Acute GVHD humanised mice showed activation of T cells with skewed TCR repertoire without significant macrophage activation.
INTERPRETATION: Using humanised mouse models, we demonstrated distinct immune mechanisms contributing acute and chronic GVHD. In cGVHD model, co-activation of human HSPC-derived macrophages and T cells educated in the recipient thymus contributed to delayed onset, multi-organ disease. In acute GVHD model, mature human T cells contained in the graft resulted in rapid disease progression. These humanised mouse models may facilitate future development of new molecular medicine targeting GVHD
tRNADB-CE: tRNA gene database curated manually by experts
We constructed a new large-scale database of tRNA genes by analyzing 534 complete genomes of prokaryotes and 394 draft genomes in WGS (Whole Genome Shotgun) division in DDBJ/EMBL/GenBank and approximately 6.2 million DNA fragment sequences obtained from metagenomic analyses. This exhaustive search for tRNA genes was performed by running three computer programs to enhance completeness and accuracy of the prediction. Discordances of assignment among three programs were found for ∼4% of the total of tRNA gene candidates obtained from these prokaryote genomes analyzed. The discordant cases were manually checked by experts in the tRNA experimental field. In total, 144 061 tRNA genes were registered in the database ‘tRNADB-CE’, and the number of the genes was more than four times of that of the genes previously reported by the database from analyses of complete genomes with tRNAscan-SE program. The tRNADB-CE allows for browsing sequence information, cloverleaf structures and results of similarity searches among all tRNA genes. For each of the complete genomes, the number of tRNA genes for individual anticodons and the codon usage frequency in all protein genes and the positioning of individual tRNA genes in each genome can be browsed. tRNADB-CE can be accessed freely at http://trna.nagahama-i-bio.ac.jp
Associations of Glucose and Blood Pressure Variability with Cardiac Diastolic Function in Patients with Type 2 Diabetes Mellitus and Hypertension: A Retrospective Observational Study
We evaluated the effects of glucose metabolism and blood pressure(BP) variability on cardiac diastolic function in patients with type 2 diabetes mellitus(T2DM) and hypertension. A total of 23 inpatients with T2DM underwent ambulatory BP monitoring(ABPM) and echocardiography. BP variability was assessed by measuring the mean BP and the standard deviation(SD) of systolic and diastolic BP over 24 hours, as well as daytime and nighttime ABPM. Cardiac diastolic function was assessed using the echocardiography E/e′ ratio. Participants had a mean age of 69.0±10.6 years, disease duration of 11.0±10.5 years, glycated hemoglobin(HbA1c) of 8.2%±1.3%, and glycated albumin(GA) of 22.0%±4.2%. Univariate analysis showed that the nighttime systolic BP, nighttime SDs of systolic and diastolic BP, urinary albumin, estimated glomerular filtration rate, and GA/HbA1c ratio were all significantly correlated with the E/e′ ratio. Moreover, stepwise multiple regression analysis identified nighttime SD of diastolic BP, urinary albumin, and GA/HbA1c ratio as independent contributors to the E/e′ ratio. In patients with T2DM and hypertension, cardiac diastolic function was associated with nighttime diastolic BP variability and the GA/HbA1c ratio
Syntheses and Characterization of New Nickel Coordination Polymers with 4,4′-Dipyridylsulfide. Dynamic Rearrangements of One-Dimensional Chains Responding to External Stimuli: Temperature Variation and Guest Releases/Re-Inclusions
Crystal structures and dynamic rearrangements of one-dimensional coordination
polymers with 4,4′-dipyridylsulfide (dps) have been studied.
Reaction of Ni(NO3)2·6H2O with dps
in EtOH yielded
[Ni(dps)2(NO3)2]
·EtOH (1), which had channels filled with guest EtOH
molecules among the four Ni(dps)2 chains. This coordination polymer
reversibly transformed the channel structure responding to temperature
variations. Immersion of 1 in m-xylene released
guest EtOH molecules to yield a guest-free coordination polymer
[Ni(dps)2(NO3)2]
(2a), which was also obtained by treatment of
Ni(NO3)2·6H2O with dps in MeOH.
On the other hand, removal of the guest molecules from 1 upon
heating at 130 °C under reduced pressure produced a guest-free
coordination polymer
[Ni(dps)2(NO3)2]
(2b). Although the 2a and 2b
guest-free coordination polymers have the same formula, they showed differences
in the assembled structures of the one-dimensional chains. Exposure of
2b to EtOH vapor reproduced 1, while
2a did not convert to 1 in a similar reaction.
Reaction of Ni(NO3)2·6H2O with dps
in acetone provided
[Ni(dps)(NO3)2(H2O)]
·Me2CO (4) with no channel structure.
When MeOH or acetone was used as a reaction solvent, the
[Ni(dps)2(NO3)2]
· (guest molecule) type coordination polymer, which was observed in
1, was not formed. Nevertheless, the reaction of
Ni(NO3)2·6H2O with dps in
MeOH/acetone mixed solution produced
[Ni(dps)2(NO3)2]·0.5(MeOH·acetone)
(5), which has an isostructural Ni-dps framework to
1
- …