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131.
Loss of mammalian Sprouty2 leads to enteric neuronal hyperplasia and esophageal achalasia 总被引:3,自引:0,他引:3
Taketomi T Yoshiga D Taniguchi K Kobayashi T Nonami A Kato R Sasaki M Sasaki A Ishibashi H Moriyama M Nakamura K Nishimura J Yoshimura A 《Nature neuroscience》2005,8(7):855-857
We report here that loss of the Sprouty2 gene (also known as Spry2) in mice resulted in enteric nerve hyperplasia, which led to esophageal achalasia and intestinal pseudo-obstruction. Glial cell line-derived neurotrophic factor (GDNF) induced hyperactivation of ERK and Akt in enteric nerve cells. Anti-GDNF antibody administration corrected nerve hyperplasia in Sprouty2-deficient mice. We show Sprouty2 to be a negative regulator of GDNF for the neonatal development or survival of enteric nerve cells. 相似文献
132.
Committing embryonic stem cells to early endocrine pancreas in vitro 总被引:12,自引:0,他引:12
Ku HT Zhang N Kubo A O'Connor R Mao M Keller G Bromberg JS 《Stem cells (Dayton, Ohio)》2004,22(7):1205-1217
A panel of genetic markers was used to assess the in vitro commitment of murine embryonic stem (ES) cells toward the endoderm-derived pancreas and to distinguish insulin-expressing cells of this lineage from other lineages such as neuron, liver, and yolk sac. There are two nonallelic insulin genes in mice. Neuronal cells express only insulin II, whereas the pancreas expresses both insulin I and II. Yolk sac and fetal liver express predominately insulin II, small amounts of insulin I, and no glucagon. We found that ES-derived embryoid bodies cultured in the presence of stage-specific concentrations of monothio-glycerol and 15% fetal calf serum, followed by serum-free conditions, give rise to a population that expresses insulin I, insulin II, pdx-1 (a pancreas marker), and Sox17 (an endoderm marker). Immunohistochemical staining shows intracellular insulin particles, and its de novo production was confirmed by staining for C-peptide. Most, but not all, of the insulin+ or C-peptide+ cells coexpress glucagon, demonstrating a differentiation pathway to pancreas rather than yolk sac or fetal liver. Addition of beta-cell specification and differentiation factors activin beta B, nicotinamide, and exendin-4 to later-stage culture increased insulin-positive cells to 2.73% of the total population, compared with the control culture, which gave rise to less than 1% insulin-staining cells. These findings suggest that stepwise culture manipulations can direct ES cells to become early endocrine pancreas. 相似文献
133.
A combination of interleukin-6 and its soluble receptor impairs sperm motility: implications in infertility associated with endometriosis 总被引:7,自引:0,他引:7
Yoshida S Harada T Iwabe T Taniguchi F Mitsunari M Yamauchi N Deura I Horie S Terakawa N 《Human reproduction (Oxford, England)》2004,19(8):1821-1825
BACKGROUND: We previously reported that the level of interleukin (IL)-6 is increased in the peritoneal fluid of women with endometriosis. This study was undertaken to assess the effects of IL-6 and soluble IL-6 receptor (sIL-6R) on in vitro sperm motility. METHODS: Sperm (n = 20) were cultured with IL-6 or sIL-6R, or with a combination of both. After 24 h cultures, sperm motility was evaluated using a computer-assisted semen analysis system. Gene and protein expressions of IL-6, IL-6 receptor (IL-6R), and glycoprotein 130 (gp130) were examined in sperm by RT-PCR analysis and western blot analysis. RESULTS: Addition of IL-6 or sIL-6R individually to the culture media had no affect on sperm motion. However, adding a combination of IL-6 and sIL-6R dose-dependently reduced the percentage of motile and rapidly moving sperm. Adding anti-IL-6R antibody abolished these adverse effects. Sperm expressed the gp130 gene and protein, but not IL-6 or IL-6R. CONCLUSIONS: A combination of IL-6 and sIL-6R may be associated with gp130 expressed in the sperm and reduce sperm motility. IL-6 and sIL-6R may contribute to the pathogenesis of endometriosis-associated infertility. 相似文献
134.
135.
Abe Y Chinzei T Isoyama T Kobayashi S Ono T Saito I Iwasaki K Ishimaru M Baba A Kouno A Ozeki T Tohyama T Imachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(3):325-332
The undulation pump total artificial heart (UPTAH) is a unique, implantable, total artificial heart (TAH) that uses undulation pumps. To achieve long-term survival in animals with physiologic hemodynamic conditions, a control method based on conductance and arterial pressure was applied to UPTAH. With this control method, called 1/R control, survival periods of 50 days (No. 0016, 49.6 kg) and 54 days (No. 0030, 42.5 kg) were obtained in adult female goats. In No. 0016, 1/R control was applied to the left pump, whereas in No. 0030, it was applied to the right pump. Another pump was used for left-right balance control. The control stability was better in No. 0030 than in No. 0016. The sucking effect of the left atrium was remarkable in No. 0016, possibly because of a time delay when left-right balance control was performed with the right pump. In No. 0016, the cause of death was probably a thrombus flown from a panus in the left atrium. It is possible that the left atrial suction effect influenced the thrombus and panus formation in the left atrium. In No. 0030, the cause of death was a small rupture of the membrane in the right pump. The rupture may have been caused by excessive negative pressure inside the pump. This pressure resulted from suction of the right atrium because of an unexpected control excursion, which was probably caused by a software bug. It will be necessary to redesign the undulation pump and improve the software to achieve longer survival periods for animals with physiologic hemodynamic conditions. 相似文献
136.
Takehara H Tada S Kataoka M Matsuo K Ueno Y Ozaki S Miyake T Fujimori Y Yamadori I Harada M 《Acta medica Okayama》2001,55(4):205-211
This study focuses on a possible role of intercellular adhesion molecule-1 (ICAM-1) in interstitial pulmonary diseases. We determined a soluble form of ICAM-1 in serum and bronchoalveolar lavage fluid (BALF) using ELISA in patients with usual interstitial pneumonia (UIP), bronchiolitis obliterance organizing pneumonia (BOOP), or nonspecific interstitial pneumonia (NSIP). In addition, we investigated the expression of ICAM-1 in the lung tissues of these patients by means of immunohistochemical staining. Serum levels of soluble ICAM-1 were significantly higher in patients with UIP or NSIP than in healthy subjects, and were also high in patients with BOOP. The soluble ICAM-1 in BALF tended to be higher in patients with UIP, BOOP, or NSIP than in normal subjects. A significant correlation was seen between soluble levels of ICAM-1 in serum and BALF. In the immunostaining of ICAM-1 of the lung tissues, ICAM-1 expression was more pronounced in patients with UIP than in those with BOOP or NSIP. The increased expression of ICAM-1 was seen in type II alveolar epithelium and vascular endothelium in patients with interstitial pneumonia. A positive correlation was observed between the degree of ICAM-1 expression in the lung tissues and the BALF levels of soluble ICAM-1. The expression of ICAM-1 in type II alveolar epithelium suggests that ICAM-1 plays a specific role in the fibrotic process of the lung, and that the measurement of soluble ICAM-1 in sera and BALF could be a useful marker for evaluating the progression of fibrosis. 相似文献
137.
Dr M. Kimura T. Sugiura Y. Fukui T. Kimura Y. Harada 《Medical & biological engineering & computing》1992,30(2):155-161
Two ways of rate control for diaphragm pacing are proposed. One is rate control using only the patients' body temperature
(method I). The other is rate control by both the patients' heart rate and body temperature (method II). To test the effectiveness
of these methods, a diaphragm pacemaker which can be controlled by both heart rate and body temperature has been developed.
It was applied to nine mongrel dogs. The pacing rate is controlled by atrial blood temperature (method I) or by both heart
rate and temperature (method II). The animal's metabolism was elevated by the administration of a pyrogenic drug. It was found
that method I is not suited to rapid changes in metabolism; however, it is useful in extreme metabolic elevation. An animal's
metabolism was supported by using method II in all ranges of metabolism. This method proved more effective than method I for
rate-responsive diaphragm pacing. 相似文献
138.
Atsushi Kikkawa Toshikazu Takata Takeshi Endo 《Macromolecular chemistry and physics.》1991,192(3):655-662
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether. 相似文献
139.
Prospective clinical evaluation of the serologic tuberculous glycolipid test in combination with the nucleic acid amplification test 总被引:4,自引:0,他引:4
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Maekura R Kohno H Hirotani A Okuda Y Ito M Ogura T Yano I 《Journal of clinical microbiology》2003,41(3):1322-1325
We have conducted a prospective controlled multicenter study to evaluate differences in the levels of clinical utility of the tuberculous glycolipid (TBGL) serodiagnostic test and the nucleic acid amplification test in patients with smear-negative active pulmonary tuberculosis (TB). The TBGL test and the PCR test were individually not so useful for the rapid diagnosis of smear-negative active pulmonary TB. However, clinical utility was considerably improved by using the TBGL test and the PCR test in combination, especially in patients with smear-negative and culture-negative active pulmonary TB and in patients with minimally advanced lesions. 相似文献
140.
Liberation of serotonin from rabbit blood platelets by bacterial cell walls and related compounds.
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K Harada S Kotani H Takada M Tsujimoto Y Hirachi S Kusumoto T Shiba S Kawata K Yokogawa H Nishimura T Kitaura T Nakajima 《Infection and immunity》1982,37(3):1181-1190
A study was made on the activity of various bacterial cell walls and peptidoglycans to liberate serotonin from rabbit blood platelets. All of the test cell walls or peptidoglycans prepared from 27 strains of 21 bacterial species were shown to cause a marked release of serotonin, regardless of differences in types of peptidoglycan and non-peptidoglycan moieties and in some biological properties. The assay made with the water-soluble "digests" of Staphylococcus epidermidis cell wall peptidoglycans, which were prepared by use of appropriate enzymes, revealed that a polymer of peptidoglycan subunits (a disaccharide-stempeptide) was definitely active in the release of serotonin, but a structural unit monomer was inactive. Among a variety of synthetic muramylpeptides and their 6-O-acyl derivatives, only 6-O-(3-hydroxy-2-docosylhexacosanoyl)-N-acetylmuramyl-L-alanyl-D-isoglutaminyl- L-lysyl-D-alanine was found to hold a strong serotonin-liberating activity. 相似文献