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21.
Ghrelin Induces Fasted Motor Activity of the Gastrointestinal Tract in Conscious Fed Rats 总被引:15,自引:1,他引:15
Kazunori Fujino Akio Inui† Akihiro Asakawa† Naoki Kihara Masaki Fujimura Mineko Fujimiya‡ 《The Journal of physiology》2003,550(1):227-240
Ghrelin is a newly discovered orexigenic peptide originating from the stomach. However, its action in regulating the fed and fasted motor activity of the digestive tract is not fully understood. In the present study, we examined the effects of intracerebroventricular ( i.c.v. ) and intravenous ( i.v. ) injection of ghrelin on the physiological fed and fasted motor activities in the stomach and duodenum of freely moving conscious rats. i.c.v. and i.v. injection of ghrelin induced fasted motor activity in the duodenum in normal fed rats, while i.v. injection of ghrelin induced fasted motor activity in both the stomach and duodenum in vagotomized rats. The effects of i.c.v. and i.v. injected ghrelin were blocked by growth hormone secretagogue receptor (GHS-R) antagonist given by the same route and also blocked by immunoneutralization of neuropeptide Y (NPY) in the brain. The effects of i.v. injected ghrelin were not altered by i.c.v. injection of GHS-R antagonist in vagotomized rats. Injection of GHS-R antagonist blocked the fasted motor activity in both the stomach and duodenum in vagotomized rats but did not affect the fasted motor activity in normal rats. Low intragastric pH inhibited the effect of ghrelin. The present results indicate that ghrelin is involved in regulation of fasted motor activity in the stomach and duodenum. Peripheral ghrelin may induce the fasted motor activity by activating the NPY neurons in the brain, probably through ghrelin receptors on vagal afferent neurons. Once the brain mechanism is eliminated by truncal vagotomy, ghrelin might be primarily involved in the regulation of fasted motor activity through ghrelin receptors on the stomach and duodenum. The action of ghrelin to induce fasted motor activity is strongly affected by intragastric pH; low pH inhibits the action. 相似文献
22.
Helical coiling structures and band patterns of hydrous metaphase chromosomes were documented three-dimensionally by low vacuum scanning electron microscopy (SEM). Fixed or unfixed isolated Chinese hamster metaphase chromosomes were stained with platinum blue (Pt blue) and observed in the backscattered electron mode for low vacuum SEM without any hypotonic treatment or drying processes. Fibrous structures were shown both in the fixed and unfixed hydrous chromosomes; helical chromatid coils and their subcoils were clarified especially in the fixed chromosomes having contrasting alternative bands of light and darkness, while the translucent perichromosomal matrix and compact fibrous structures were recognized in the unfixed chromosomes. The helical coils were more clearly represented in a loosened chromatid of metaphase chromosomes. Treatment with a tris-HCl buffer solution and Pt blue staining in a hydrous condition successfully produced banding patterns similar to G-bands on metaphase chromosomes. These banded chromosomes observed by low vacuum SEM were also analyzed stereoscopically by field emission SEM after critical point drying. These findings indicate that: 1) native or unfixed chromosomes maintain the compact arrangement of high-order helical structures covered with the peri-chromosomal matrix; 2) helical coiling appearances of chromatids frequently observed in previous papers might be caused by loosening of the final level of the high-order structure of the metaphase chromosome; and 3) banding patterns might be produced by the rearrangement or reorganization of chromatin fibers at the 30 nm fiber level after the extraction of some chromosomal components including the peri- or intra-chromosomal materials during the banding procedure. 相似文献
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Takuma Narita Shingo Hatakeyama Shintaro Narita Masahiro Takahashi Toshihiko Sakurai Sadafumi Kawamura Senji Hoshi Jiro Shimoda Toshiaki Kawaguchi Shigeto Ishidoya Koji Mitsuzuka Yoichi Arai Akihiro Ito Norihiko Tsuchiya Tomonori Habuchi Chikara Ohyama 《Translational andrology and urology》2021,10(1):417
BackgroundThe clinical benefit of the combined androgen blockade (CAB) therapy over luteinizing hormone-releasing hormone analog (LH-RHa) monotherapy for hormone naïve metastatic prostate cancer (mHNPC) is unclear. Therefore, we retrospectively compare the effectiveness of CAB with the LH-RHa monotherapy on the prognosis of Japanese patients with mHNPC.MethodsWe retrospectively evaluated the prognosis of 517 patients diagnosed with mHNPC between August 2001 and May 2017. The patients’ data were obtained from the Michinoku Urological Cancer Research Group database and Hirosaki University-related hospitals. Patients were divided into the CAB and LH-RHa monotherapy groups based on primary androgen deprivation therapy (ADT). Overall survival (OS), cancer-specific survival (CSS), and castrate-resistant prostate cancer-free survival (CRPC-FS) were compared between the two groups using the Kaplan-Meier curve analysis. Inverse probability of treatment weighting (IPTW)-adjusted Cox hazard proportional analyses was performed to investigate the effect of primary ADT on oncological outcomes.ResultsThe median age was 73 years old. The numbers of patients in the CAB and LH-RHa monotherapy groups were 447 and 70, respectively. The Kaplan-Meier curve analysis showed no significant differences in either 5-year OS (56.7% vs. 52.5%, P=0.277), CSS (61.1% vs. 56.4%, P=0.400), and CRPC-FS (33.1% vs. 31.1%, P=0.529) between the groups. IPTW-adjusted multivariate Cox hazard proportional analyses showed no significant differences in OS, CSS, and CRPC-FS between the two groups.ConclusionsNo significant differences in oncological outcomes were observed between the CAB and LH-RHa monotherapy groups in patients with mHNPC. 相似文献
27.
Koichi Yasuda Hideki Minatogawa Yasuhiro Dekura Seishin Takao Masaya Tamura Nayuta Tsushima Takayoshi Suzuki Satoshi Kano Takatsugu Mizumachi Takashi Mori Kentaro Nishioka Motoyasu Shido Norio Katoh Hiroshi Taguchi Noriyuki Fujima Rikiya Onimaru Isao Yokota Keiji Kobashi Shinichi Shimizu Akihiro Homma Hiroki Shirato Hidefumi Aoyama 《Journal of radiation research》2021,62(2):329
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia. 相似文献
28.
I. Sano Y. Kakimoto K. Taniguchi M. Takesada 《Journal of molecular medicine (Berlin, Germany)》1960,38(1):41-45
Ohne Zusammenfassung 相似文献
29.
The chemical and radio toxicity of 125-5-iodo-2-deoxyuridine (125IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of 125IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and 125IUDR was added to the dishes at levels ranging from 0.1 µCi/ml to 5.0 µCi/ml of media, the growth rate of the cells for 24h was similar to that of non-labeled cells. Nude mice were given intravenous injections of 125IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis. 相似文献
30.
Finger bougie method compared with pyloroplasty in the gastric replacement of the esophagus 总被引:2,自引:0,他引:2
Yamashita Y Hirai T Mukaida H Yoshimoto A Kuwahara M Inoue H Toge T 《Surgery today》1999,29(2):107-110
To elucidate the necessity of pyloroplasty for the gastric tube through the posterior mediastinum in esophageal surgery, gastric
emptying and duodenogastric reflux (DGR) were evaluated in 16 cases undergoing an anterior pylorectomy (group P) and in 16
cases treated by the finger bougie method (group F). First, the obstruction and reflux symptoms were examined based on a patient
questionnaire using a brief scoring system. The median value of the symptom score showed the patients in P to have more symptoms
than those in F; however, the difference was not significant (8.0 vs 6.0). Secondly, the swallowed Tc O4
− (85 MBq) was counted using a gamma camera at three sites on the sternal bone in the upright position based on a gastric transit
scintigram. Both the descending time of the RI peak and the clearance rates were similar between the two groups. Thirdly,
intragastric 24-h pH monitoring was carried out. Antimony pH sensors were anchored 5 and 15 cm below the esophagogastrostomy.
We could not find any difference between the two groups in both the % time pH>4 and %time pH>7. These findings thus revealed
no big difference between groups P and F. The finger bougie method to drain the vagotomized posterior mediastinal stomach
was found to achieve results similar to conventional pyloroplasty, while it was also simpler and safer. 相似文献