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51.
We examined the possibility that lumbar skin warming can increase gastrointestinal motility by investigating the electrogastrogram (EGG), blood pressure, and heart rate with psychometric ratings in healthy humans. Scores of mood state profiles showed that lumbar skin warming (42 degrees C, 20 min) decreased tension-anxiety, depression, anger-hostility, fatigue, and confusion of the participants. A multiple bandpass filter analysis of EGGs showed that a postural transition from orthostatic to supine for measurement caused an increase in dominant frequency of 25-29% towards the frequencies of the normal interdigestive migrating motor complex (IMC). The spectral power of the IMC band, 2.55-3.05 cycles/min, was increased by 20 min-warming, reflecting the increase in gastric contractility. No increase in the spectral power was observed in the time-matched control group without skin warming. Therefore, an increase in contractility is a characteristic of lumbar skin warming. The systolic blood pressure increased by 15% during warm stimulation. Interbeat intervals were not influenced by warm stimulation. An analysis of interbeat intervals by a fast Fourier transform method showed that the cardiac sympathetic and parasympathetic nerves did not play a major role in raising the blood pressure. Vasoconstriction of the mesenteric artery was therefore considered to cause a blood pressure increase during warming. It is hypothesized that vasoconstriction of the visceral arteries by lumbar skin warming increases the blood pressure and gastrointestinal contractility. 相似文献
52.
Muroya K Hasegawa T Ito Y Nagai T Isotani H Iwata Y Yamamoto K Fujimoto S Seishu S Fukushima Y Hasegawa Y Ogata T 《Journal of medical genetics》2001,38(6):374-380
We report on GATA3 analysis and the phenotypic spectrum in nine Japanese families with the HDR syndrome (hypoparathyroidism, sensorineural deafness, and renal dysplasia) (MIM 146255). Fluorescence in situ hybridisation and microsatellite analyses showed heterozygous gross deletions including GATA3 in four families. Sequence analysis showed heterozygous novel mutations in three families: a missense mutation within the first zinc finger domain at exon 4 (T823A, W275R), an unusual mutation at exon 4 (900insAA plus 901insCCT or C901AACCCT) resulting in a premature stop at codon 357 with loss of the second zinc finger domain, and a nonsense mutation at exon 6 (C1099T, R367X). No GATA3 abnormalities were identified in the remaining two families. The triad of HDR syndrome was variably manifested by patients with GATA3 abnormalities. The results suggest that HDR syndrome is primarily caused by GATA3 haploinsufficiency and is associated with a wide phenotypic spectrum.
Keywords: GATA3; HDR syndrome; phenotypic spectrum; mutation analysis 相似文献
Keywords: GATA3; HDR syndrome; phenotypic spectrum; mutation analysis 相似文献
53.
HeLa cell invasiveness and O antigen of Shigella flexneri as separate and prerequisite attributes of virulence to evoke keratoconjunctivitis in guinea pigs. 总被引:9,自引:7,他引:9
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N Okamura T Nagai R Nakaya S Kondo M Murakami K Hisatsune 《Infection and immunity》1983,39(2):505-513
Many rough mutants selected from isogenic smooth virulent and avirulent strains of Shigella flexneri were examined for virulence, using tissue culture infection and Sereny tests. Many of the rough mutants isolated from a virulent smooth strain were capable of penetrating tissue culture cells but incapable of producing a positive Sereny test. In contrast, we could not obtain from smooth avirulent strains any rough mutants capable of penetrating HeLa cells. Chemical analysis of lipopolysaccharide of some representative rough strains showed several patterns of sugar composition with a range of from Ra to Re chemotypes. There was no correlation between HeLa cell invasiveness and chemotypes of lipopolysaccharides, thus indicating little significance of oligosaccharides of the rough core as well as O antigens in the ability of S. flexneri to penetrate HeLa cells. When these invasive rough strains were given O antigen genes from a smooth avirulent Shigella Hfr strain, most of the transconjugants that expressed O antigens regained the ability to evoke keratoconjunctivitis in guinea pigs. We also examined the chromosomal loci of HeLa cell invasion by transferring carbohydrate fermentation genes of Escherichia coli K-12 Hfr and found two chromosomal loci, the rha and lac-gal regions, which control the ability to penetrate HeLa cells. These results suggested that O antigens and ability to penetrate tissue culture cells are independent and prerequisite attributes of virulence in Shigella flexneri to evoke keratoconjunctivitis in guinea pigs. 相似文献
54.
Fukai Y Amino H Hirawake H Yabu Y Ohta N Minagawa N Sakajo S Yoshimoto A Nagai K Takamiya S Kojima S Kita K 《Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology》1999,124(2):141-148
Trypanosome alternative oxidase (TAO) is the terminal oxidase of the respiratory chain of long slender bloodstream forms (LS forms) of African trypanosoma, which causes sleeping sickness in human and nagana in cattle. TAO is a cytochrome-independent, cyanide-insensitive quinol oxidase and these properties are quite different from those of the bacterial quinol oxidase which belongs to the heme-copper terminal oxidase superfamily. Only little information concerning the molecular structure and enzymatic features of TAO have been available, whereas the bacterial enzyme has been well characterized. In this study, a cDNA encoding TAO from Trypanosoma brucei brucei was cloned into the expression vector pET15b (pTAO) and recombinant TAO was expressed in Escherichia coli. The growth of the transformant carrying pTAO was cyanide-resistant. A peptide with a molecular mass of 37 kDa was found in the cytoplasmic membrane of E. coli, and was recognized by antibodies against plant-type alternative oxidases from Sauromatum guttatum and Hansenula anomala. Both the ubiquinol oxidase and succinate oxidase activities found in the membrane of the transformant were insensitive to cyanide, while those of the control strain, which contained vector alone, were inhibited. This cyanide-insensitive growth of the E. coli carrying pTAO was inhibited by the addition of ascofuranone, a potent and specific inhibitor of TAO ubiquinol oxidase. The ubiquinol oxidase activity of the membrane from the transformant was sensitive to ascofuranone. These results clearly show the functional expression of TAO in E. coli and indicate that ubiquinol-8 in the E. coli membrane is able to serve as an electron donor to the recombinant enzyme and confer cyanide-resistant and ascofuranone-sensitive growth to E. coli. This system will facilitate the biochemical characterization of the novel terminal oxidase, TAO, and the understanding on the mechanism of the trypanocidal effect of ascofuranone. 相似文献
55.
Yoshinori Seko Shigeru Ishiyama Toshiro Nishikawa Takeshi Kasajima Michiaki Hiroe Shin Suzuki Sugao Ishiwata Sachio Kawai Yuetsu Tanaka Miyuki Azuma Tetsuji Kobata Hideo Yagita Ko Okumura Ryozo Nagai 《Cardiovascular pathology》2002,11(3):166-170
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis. 相似文献
56.
Sotos syndrome and haploinsufficiency of NSD1: clinical features of intragenic mutations and submicroscopic deletions 总被引:2,自引:0,他引:2
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57.
We evaluated human physiological responses and the performance of manual tasks during exposure to severe cold (–25°C) at
night (0300–0500 hours) and in the afternoon (1500–1700 hours). Thirteen male students wearing standard cold protective clothing
occupied a severely cold room (–25°C) for 20 min, and were then transferred to a cool room (10°C) for 20 min. This pattern
of exposure was repeated three times, for a total time of exposure to extreme cold of 60 min. The experiments were started
either at 1500 hours or 0300 hours and measurements of rectal temperature, skin temperature, blood pressure, performance in
a counting task, hand tremor, and subjective responses were made in each condition. At the end of the experiment at night
the mean decrease in rectal temperature [0.68 (SEM 0.04)°C] was significantly greater than that at the end of the experiment
in the afternoon [0.55 (SEM 0.08)°C, P<0.01]. After the second cold exposure at night the mean increase in diastolic blood pressure [90 (SEM 2.0) mmHg] was significantly
greater than that at the end of the second cold exposure in the afternoon [82 (SEM 2.8) mmHg, P<0.01]. At the end of the second cold exposure at night, mean finger skin temperature [11.8 (SEM 0.8)°C] was significantly
higher than that at the comparable time in the afternoon [9.0 (SEM 0.7)°C, P<0.01]. Similarly for the toe, mean skin temperature at the start of the second cold exposure at night [25.6 (SEM 1.5)°C]
was significantly higher than in the afternoon [20.1 (SEM 0.8)°C, P<0.01]. The increased skin temperatures in the periphery resulted in increased heat loss. Since peripheral skin temperatures
were highest at night, the subjects noted diminished sensations of thermal cold and pain at that time. Manual dexterity at
the end of the first cold exposure at night [mean 83.7 (SEM 3.6) times·min–1] had decreased significantly more than at the end of the first cold exposure in the afternoon [mean 89.4 (SEM 3.5) times·min–1, P<0.01]. These findings of a lowered rectal temperature and diminished manual dexterity suggest that there is an increased
risk of both hypothermia and accidents for those who work at night.
Electronic Publication 相似文献
58.
K Nagai M Nagao M Nagao S Yanai K Minagawa Y Takahashi Y Takekoshi A Ishizaka Y Matsuzono O Kobayashi T Itagaki 《Journal of medical genetics》1998,35(4):342-344
We report a girl with oral, facial, and digital anomalies including multiple alveolar frenula, lobulated tongue with nodules, a posterior cleft palate, hypertelorism, a prominent forehead with a large anterior fontanelle, and postaxial polydactyly in both hands and the right foot, features compatible with the oral-facial-digital syndrome (OFDS). In addition, she had bilateral microphthalmia, optic disc coloboma, and retinal degeneration with partial detachment, thus establishing a diagnosis of OFDS type IX. Dandy-Walker malformation and retrobulbar cysts were observed on MRI. These additional malformations have not been reported in OFDS type IX. The frequent apnoeic spells which occurred immediately after birth were relieved after cystoperitoneal shunt implantation for hydrocephalus. Considering our case and previous reports of OFDS type IX, including two male sibs, a boy born to consanguineous parents, and three females, inheritance is probably autosomal recessive. 相似文献
59.
Bradykinin Stimulates Type II Alveolar Cells to Release Neutrophil and Monocyte Chemotactic Activity and Inflammatory Cytokines 总被引:2,自引:0,他引:2
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Sekiya Koyama Etsuro Sato Hiroshi Nomura Keishi Kubo Masakazu Miura Tetsuji Yamashita Sonoko Nagai Takateru Izumi 《The American journal of pathology》1998,153(6):1885-1893
In the present study, we evaluated the potential of bradykinin (BK) to induce the release of neutrophil and monocyte chemotactic activity (NCA and MCA) and cytokines from an alveolar type II epithelial cell line, A549 cells. BK stimulated A549 cells to release NCA and MCA in a dose- and time-dependent manner (P < 0.001). Checkerboard analysis revealed that both NCA and MCA involved chemotactic and chemokinetic activity. Molecular sieve column chromatography showed three molecular weight masses (near 19 kd, 8 kd, and 400 d) for NCA and several molecular weight peaks (near 66 kd, 25 kd, 19 kd, 16 kd, and 400 d) for MCA. The release of NCA and MCA was inhibited by cycloheximide and lipoxygenase inhibitors (P < 0.01). The NCA and MCA were inhibited by leukotriene B4 (LTB4) receptor antagonist (P < 0.01), and the concentration of LTB4 was high enough for NCA and MCA. Antibodies to interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) attenuated NCA (P < 0.01), and antibodies to monocyte chemotactic protein-1 (MCP-1), G-CSF, and transforming growth factor (TGF)-β attenuated MCA (P < 0.01). The levels of IL-8, G-CSF, MCP-1, and TGF-β increased time dependently (P < 0.01). BK also stimulated the release of ILeukin-6 from A549 cells (P < 0.001). The receptors responsible for the release of NCA, MCA, and individual chemokines involved both BKB1 and BKB2 receptors. These data suggest that BK may stimulate alveolar type II pneumocytes to release inflammatory cytokines, which then may modulate the lung inflammation. 相似文献
60.
Comparison of an immunochromatography test with multiplex reverse transcription-PCR for rapid diagnosis of respiratory syncytial virus infections
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Kuroiwa Y Nagai K Okita L Ukae S Mori T Hotsubo T Tsutsumi H 《Journal of clinical microbiology》2004,42(10):4812-4814
A new commercial rapid 10-min one-step immunochromatography (IC) test, SAS RSV test, was compared to another IC test, Directigen EZ RSV, employing RT-PCR as the "gold standard" for detecting respiratory syncytial virus. Of 102 clinical samples, 79 were positive by RT-PCR, 66 (82.5%) were positive with the SAS RSV test, and 55 (69.6%) were positive with Directigen EZ RSV. The specificity of the new test was 91.3% (21 of 23), similar to that of Directigen EZ RSV (100% [23 of 23]). This test performs well enough to be used for patient care. 相似文献