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991.
Masanori Kosako Hiraku Akiho Hiroto Miwa Motoyori Kanazawa Shin Fukudo 《BioPsychoSocial medicine》2018,12(1):18
Background
Rome III was revised to Rome IV in May 2016. One important change in the Rome IV criteria is that abdominal pain must be present for a diagnosis of irritable bowel syndrome (IBS). Under Rome III, in contrast, patients with abdominal discomfort only could be diagnosed with IBS, but these cases under Rome IV are now classified as unspecified functional bowel disorder (FBD). In a simple comparison of Rome III and Rome IV, it is unclear whether this difference reflects the influence of symptomatic frequency or the presence of abdominal pain. In particular, the influence of abdominal pain restriction on the diagnosis of IBS with predominant constipation (IBS-C) in the Rome IV criteria is largely unknown.Methods
We reclassified subjects from a Japanese internet survey experiencing abdominal pain or discomfort at least one day each week as surrogate Rome III IBS-C subjects. Among them, we then reclassified subjects experiencing abdominal pain as surrogate Rome IV IBS-C subjects and subjects not experiencing abdominal pain as surrogate Rome IV FBD subjects. Symptoms were quantified and compared between the two groups.Results
The surrogate Rome IV IBS-C subjects felt a significantly higher degree of anxiety in their daily lives (p?<?0.001) compared with the surrogate Rome IV FBD subjects. The combined female and 20–49?years surrogate Rome IV IBS-C subjects felt a higher degree of anxiety in their daily lives (p?<?0.05) than the respective Rome IV FBD subjects.Conclusions
These results suggest that female IBS-C patients aged 20–49?years with abdominal pain in Rome IV have more anxiety than those without abdominal pain in Rome III. Changes in the diagnostic criteria from Rome III to Rome IV will better identify candidates for the biopsychosocial approach.Trial registration
Although this survey was an anonymous internet survey, we obtained informed consent for the study as an online response. The disclosure of this study was approved by the Ethics Committee of Tohoku University Graduate School of Medicine (approval number: 2015–1-405).992.
Effects of various kinds of stimulation on ornithine decarboxylase activity in superior cervical sympathetic and nodose ganglia of rats 总被引:2,自引:0,他引:2
Levels of cyclic nucleotides and ornithine decarboxylase (ODC) activity were examined following the application of various kinds of stimuli to superior cervical sympathetic ganglia (SCG), nodose ganglia, and vagus nerve fibers excised from the rat. The level of cyclic GMP in the SCG rose rapidly to about 4.5- to 7.5-fold the unstimulated control with 10 min of incubation after applications of preganglionic electrical stimulation (10 Hz), acetylcholine (ACh; 1 mM), or high extracellular K+ ( [K+]0, 70 mM). The cyclic GMP level in nodose ganglia was increased less than in the SCG by either ACh or high [K+]0 but was not affected by ACh in vagus fibers. Cyclic AMP in the SCG was also increased about 4- to 5.5-fold over the control within 10 min with the addition of ACh, norepinephrine (NE; 0.05 mM), or high [K+]0. Although NE caused a small increase in cyclic AMP, neither ACh nor high [K+]0 produced any appreciable change in nodose ganglia or vagus fibers. The ODC activity in the SCG was increased by preganglionic stimulation of 3- to 4-hr duration but not by a shorter period. A similar change in ODC activity was caused by the addition of oxotremorine (1 mM), isoproterenol (0.1 mM), NE, cyclic AMP (1 mM), or dibutyryl cyclic GMP (1 mM). The effect was exaggerated by the further addition of 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor. The increase in ODC activity caused by ACh was abolished by a muscarinic cholinergic antagonist, atropine (0.01 mM), and following axotomy for a week, but not by a nicotinic antagonist or by denervation in the SCG. A similar increase in ganglionic ODC activity by NE was inhibited by an adrenergic blocker, propranolol (0.01 mM), and following axtotomy for a week, but not by denervation. Cholinergic or adrenergic stimulation did not cause an increase in ODC activity in nodose ganglia or vagus fibers. These results suggest that the stimulation-induced increase in ODC activity occurs in postganglionic neurons rather than in satellite glial cells and is mediated by muscarinic cholinergic or adrenergic receptors. The process appears to involve cyclic nucleotide-mediated protein biosynthesis in the SCG. 相似文献
993.
The primary structure of phosphoenolpyruvate carboxylase of Escherichia coli. Nucleotide sequence of the ppc gene and deduced amino acid sequence 总被引:12,自引:0,他引:12
The nucleotide sequence of the ppc gene, the structural gene for phosphoenolpyruvate carboxylase [EC 4.1.1.31], of Escherichia coli K-12 was determined. The gene codes for a polypeptide comprising 883 amino acid residues with a calculated molecular weight of 99,061. The amino acid sequence deduced from the nucleotide sequence was entirely consistent with the protein chemical data obtained with the purified enzyme, including the NH2- and COOH-terminal sequences and amino acid composition. The coding region is preceded by two putative ribosome binding sites, and is followed closely by a good representative of rho-independent terminator. The codon usage in the ppc gene suggests a moderate expression of the gene. The secondary structure of the enzyme was predicted from the deduced amino acid sequence. 相似文献
994.
G T Miwa J S Walsh G L Kedderis P F Hollenberg 《The Journal of biological chemistry》1983,258(23):14445-14449
Intramolecular isotope effects were determined for the N-demethylation of N-methyl-N-trideuteriomethylaniline catalyzed by two isozymes of cytochrome P-450 and several peroxidases in order to differentiate between deprotonation and hydrogen atom abstraction steps. Lactoperoxidase, hemoglobin, myoglobin, and two isozymes of horseradish peroxidase catalyzed the hydroperoxide-dependent N-demethylation at initial rates ranging from 20 to 1700 min-1. These hemeproteins exhibited large and comparable intramolecular isotope effects (kH/kD = 8.6 to 10.1). In contrast, two isozymes of cytochrome P-450 as well as chloroperoxidase (v = 1.5 to 1700 min-1) gave low isotope effects (kH/kD = 1.7 to 3.1) under identical conditions. Catalase exhibited an intermediate intramolecular isotope effect (kH/kD = 5.4). These results have been interpreted to indicate that most of the hemeproteins investigated catalyze N-demethylation reactions via alpha-carbon hydrogen atom abstraction, while the reactions catalyzed by cytochrome P-450 and chloroperoxidase proceed via alpha-carbon deprotonation. 相似文献
995.
The effects of D-glucose anomers on the germination of dormant spores of Bacillus megaterium QM B1551 were studied, alpha-D-Glucose (1 mM) slightly initiated the germination of the dormant spores during 10 min incubation at 37 degrees C, while about 60% of the dormant spores became germinated with beta-D-glucose (1 mM) in the same conditions. From the above observations and the finding that only a trace amount of alpha- or beta-D-glucose may bind with the dormant spores, it is speculated that the beta-D-glucose-stereospecific receptor site for the germination exists on the surface of the dormant spores of the bacillus. 相似文献
996.
The interaction between cytochrome P-450 and NADPH-cytochrome c reductase during catalysis has been investigated with a reconstituted monooxygenase system composed of the two purified enzyme components and synthetic phospholipid. Steady state kinetic data are consistent with a scheme in which the formation of a binary complex between the two proteins precedes catalysis. The formation of this binary complex is described by a simple mass action equation. In agreement with this equation, the observed Vmax for benzphetamine N-demethylation was found to be directly proportional to the calculated concentration of the cytochrome P-450 . reductase complex. Furthermore, with appropriate reductase/cytochrome P-450 mole ratios, the Vmax could be shown to be linearly dependent on either the reductase or the cytochrome P-450 concentration alone. In contrast, the Km parameter is independent of the complex concentration, indicating that no change in the rate-limiting step has occurred. Thus a distinction should be made between a rate-limiting enzyme component and the rate-limiting step in this multienzyme system. 相似文献
997.
ADP-ribosyltransferase activity associated with chromatin is two- to tenfold higher in simian virus 40 (SV40)-transformed cells than in untransformed cells. When confluent transformed cells were subcultured, their specific enzyme activity first decreased two- to fourfold and the rapidly increased during the logarithmic phase of growth. This increase ceased or slowed down when the cells entered the stationary phase. In contrast, the activity in the untransformed cells remained low throughout the growth cycle. In SV40tsA-transformed cells (ts = temperature sensitive), this density-dependent increase in the enzyme activity was observed when the cells were cultivated at the permissive temperature, whereas the activity remained low at the restrictive temperature. The enzyme activity did not increase during induction of cellular DNA synthesis in quiescent cells either by addition of fresh medium or by infection with SV40. The chromatin-associated enzyme activity extracted with 1 m NaCl was eluted together with almost all the DNA-binding proteins from a phosphocellulose column with 0.6 m NaCl. The enzyme activity in this fraction from transformed cells, measured with or without added DNA and histones, was higher than that in a similar fraction from untransformed cells, reflecting the difference in the original activities present in the nuclei of these cells. The chain lengths of poly(ADP-ribose) formed by chromatin from SV40-transformed and untransformed cells were not significantly different. These results suggest that the number of initiation sites for ADP-ribosylation is increased in the chromatin of SV40-transformed cells compared to that of untransformed cells. 相似文献
998.
A PVC-based electrode sensitive to DDA+ as a device for monitoring the membrane potential in biological systems 总被引:20,自引:0,他引:20
A polyvinyl chloride (PVC)-based membrane electrode sensitive to dibenzyldimethyl ammonium cation (DDA+) was constructed, and operational parameters such as the selectivity coefficients, the detection limit, and the response time were obtained. In comparison with the selectivity coefficients obtained with the previous liquid-membrane electrode, significant improvement was not obtained, but the response time became pronouncedly shorter. Furthermore, the electrode lifetime was remarkably prolonged. With the electrode developed, the change in the membrane potential of liposomes containing dibutyl ferrocene which separated oxidizing and reducing agent solutions was measured. The DDA+ uptake, U, and the membrane potential estimated from U changed in accordance with the redox potential in the medium when the concentration of internal ferricyanide was kept constant. The membrane potential collapsed when the uncoupler of oxidative phosphorylation was added. The ANS fluorescence measurement indicated that negative charges appeared on energization with oxidizing-reducing agent. The change in membrane potential of mitochondria during energization was also measured. It was found that the liposome described above is a good model for the generation of membrane potentials in mitochondria. 相似文献
999.
A rapid and simple procedure has been developed for the purification of a phenobarbital-inducible form of cytochrome P-450 from the liver microsomes of phenobarbitalpretreated rats. Within 2 days approximately 1000–1500 nmol of highly purified cytochrome P-450 with a specific content of 16 nmol/mg protein can be recovered from 4 g of microsomal protein. The procedure consists of solubilization of microsomal protein with sodium cholate, fractionation with polyethylene glycol, and column chromatography at room temperature on DEAE-cellulose. The resulting DEAE-cellulose fraction electrophoreses on polyacrylamide gels in the presence of sodium dodecyl sulfate as a major protein band with a minimum molecular weight of 52,000 and a few faint bands. Further chromatography on QAE Sephadex A-25 essentially removes these faint bands and increases the specific content slightly to 17 nmol/mg protein. Relatively low amounts of this form of cytochrome P-450 appear to be present in microsomes of untreated rats since less than 1% can be recovered as the DEAE-cellulose fraction by this procedure. An identical form is inducible by phenobarbital in rats of different ages and sex. In a reconstituted system under optimal assay conditions, this form of cytochrome P-450 catalyses the N-demethylation of benzphetamine with a turnover number greater than 100 and hydroxylates testosterone at the 16α position but not at the 6β or 7α position. 相似文献
1000.
A 13C NMR study of poly(adenosine diphosphate ribose) and its monomers: evidence of alpha-(1'''' leads to 2'') ribofuranosy1 ribofuranoside risidue. 总被引:4,自引:2,他引:2
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M Miwa H Sait? H Sakura N Saikawa F Watanabe T Matsushima T Sugimura 《Nucleic acids research》1977,4(11):3997-4005
The 13C NMR spectra of poly(adenosine diphosphate ribose), ribosyl adenosine 5', 5'-bis(phosphate) and related compounds were analyzed. The structure of the ribose-ribose linkage was determined as alpha-(1' leads to 2')ribofuranosyl ribofuranoside, from the 13C chemical shifts of methyl-alpha- and methyl-beta-D-ribofuranosides, and from the downfield displacements of 13C NMR signals by glycosidic bond formation. 相似文献