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41.
Differential effects of transforming growth factor type beta on the growth and function of adrenocortical cells in vitro. 总被引:1,自引:2,他引:1 下载免费PDF全文
M Hotta A Baird 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(20):7795-7799
Transforming growth factor type beta (TGF-beta) suppresses basal as well as corticotropin (ACTH)-stimulated steroid formation by bovine adrenocortical cells in culture. The effect is dose dependent and is not accompanied by any change in adrenocortical cell growth. The minimum effective dose of TGF-beta is 4 X 10(-13) M (10 pg/ml), and maximal inhibition is observed at a concentration of 4 X 10(-11) M (1 ng/ml). A 16- to 20-hr incubation with TGF-beta is required to decrease steroidogenesis, and 12-18 hr are required before cells treated with TGF-beta recover complete responsiveness to corticotropin. Increases in cAMP mediated by corticotropin, forskolin, and isobutylmethylxanthine are not modified by the addition of TGF-beta; thus adenylate cyclase activity is unaffected by TGF-beta. Although TGF-beta inhibits the formation of all of the delta 4-steroids measured (including cortisol, corticosterone, aldosterone, and androstenedione), its effect can be completely reversed by the addition of 25-hydroxycholesterol, pregnenolone, or progesterone to the cells. In contrast, the addition of low density lipoprotein has no effect suggesting that TGF-beta targets the conversion of cholesterol precursors to cholesterol. The results demonstrate a highly potent effect of TGF-beta on the differentiated function of the adrenocortical cell. The inhibition of steroidogenesis can be dissociated from any effect on cell proliferation, and it occurs distal to the formation of cAMP but proximal to the formation of cholesterol. The results suggest that in the adrenal, TGF-beta or TGF-beta-like proteins may be playing an important role in modifying the differentiated state of the adrenocortical cell. 相似文献
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Masao Yoshida Kenichiro Imai Kinichi Hotta Yuichiro Yamaguchi Masaki Tanaka Naomi Kakushima Kohei Takizawa Hiroyuki Matsubayashi Hiroyuki Ono 《International journal of colorectal disease》2014,29(3):365-371
Purpose
Carbon dioxide (CO2) insufflation reduces abdominal pain and discomfort after endoscopic procedures; however, there is no previous study focusing the safety of CO2 insufflation for patients with obstructive ventilatory disturbance. Here, we investigated the safety of CO2 insufflation during colorectal endoscopic submucosal dissection (ESD) for patients with obstructive disturbance.Methods
Between January 2010 and January 2013, colorectal ESD was performed using CO2 insufflation for 385 consecutive patients. End-tidal CO2 (EtCO2) and transcutaneous oxygen saturation (SpO2) were consecutively measured from the time before insertion of the colonoscope to the end of ESD. Patients were monitored by two nurses during the procedure and controlled for clinical symptoms of hypercapnia such as apnea or a depressed level of consciousness. According to their respiratory function, patients were stratified into a normal group and an obstructive disturbance group. We retrospectively compared EtCO2 and SpO2 during the procedures and the incidence of symptoms related to CO2 retention between the two groups.Results
The obstructive disturbance group consisted of 77 patients. There were similar changes of EtCO2 in the obstructive disturbance group and normal group and no significant rise in EtCO2. The maximum EtCO2 level in any patient was <60 mmHg. In the obstructive disturbance group, there were no symptoms associated with CO2 retention. There were no significant differences in the median SpO2 between both groups and no prolonged drop of SpO2.Conclusions
CO2 insufflation during colorectal ESD is safe for patients with obstructive ventilatory disturbance. 相似文献44.
Masanori Atsukawa Akihito Tsubota Hidenori Toyoda Koichi Takaguchi Makoto Nakamuta Tsunamasa Watanabe Kojiro Michitaka Tadashi Ikegami Akito Nozaki Haruki Uojima Shinya Fukunishi Takuya Genda Hiroshi Abe Naoki Hotta Kunihiko Tsuji Chikara Ogawa Yoshihiko Tachi Toshihide Shima Noritomo Shimada Chisa Kondo Takehiro Akahane Yoshio Aizawa Yasuhito Tanaka Takashi Kumada Katsuhiko Iwakiri 《Alimentary pharmacology & therapeutics》2019,49(9):1230-1241
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Keisuke Endo Takayuki Miki Takahito Itoh Hirofumi Kubo Ryosuke Ito Kouhei Ohno Hiroyuki Hotta Nobuo Kato Tomoaki Matsumoto Aya Kitamura Mai Tamayama Takako Wataya Ayaka Yamaya Rei Ishikawa Hitoshi Ooiwa 《Internal medicine (Tokyo, Japan)》2022,61(1):37
Objective In this study, we investigated whether and how the COVID-19 pandemic affected glycemic control and blood pressure (BP) control in patients with diabetes mellitus (DM). Methods DM patients whose HbA1c level was measured regularly before and after the declaration of a state of emergency were included in this study. Some patients were given questionnaires about changes in their lifestyle to determine the factors affecting glycemic control and BP control. Results The median HbA1c level of the 804 patients increased significantly from 6.8% before the state of emergency to 7.1% and 7.0% during and after the state of emergency, respectively. This was in contrast to the decrease one year earlier due to seasonal variations. In the 176 patients who responded to the questionnaire, the HbA1c level also increased significantly during and after the state of emergency. The worsening of glycemic control was more pronounced in the group that had achieved HbA1c of <7% before the state of emergency than in those with higher values. Unlike the rise in HbA1c, the BP did not rise during the state of emergency but did rise significantly afterwards. There was no marked decrease in HbA1c or BP after the state of emergency, even in patients who responded that they were much more careful with their diet, ate less, or exercised more. Conclusions The COVID-19 pandemic worsened glycemic control and BP control, even in patients who perceived no marked change in their diet or exercise, suggesting that more active lifestyle guidance is necessary for good treatment of DM patients. 相似文献
48.
Zebra finches (Taeniopygia guttata) use their voices for communication. Song structures in the songs of individual males are important for sound recognition in females. The caudomedial mesopallium (CMM) and nidopallium (NCM) are known to be essential higher auditory regions for sound recognition. These two regions have also been discussed with respect to their fundamental functions and song selectivity. To clarify their functions and selectivity, we investigated latencies and spiking patterns and also developed a novel correlation analysis to evaluate the relationship between neural activity and the characteristics of acoustic factors. We found that the latencies and spiking patterns in response to song stimuli differed between the CMM and NCM. In addition, our correlation analysis revealed that amplitude and frequency structures were important temporal acoustic factors for both regions. Although the CMM and NCM have different fundamental functions, they share similar encoding systems for acoustic factors. 相似文献
49.
Harumi Hotta Kazuto Masamoto Sae Uchida Yuta Sekiguchi Hiroyuki Takuwa Hiroshi Kawaguchi Kazuhiro Shigemoto Ryo Sudo Kazuo Tanishita Hiroshi Ito Iwao Kanno 《Journal of cerebral blood flow and metabolism》2013,33(9):1440-1447
To clarify mechanisms through which activation of the nucleus basalis of Meynert (NBM) increases cerebral cortical blood flow, we examined whether cortical parenchymal arteries dilate during NBM stimulation in anesthetized mice. We used two-photon microscopy to measure the diameter of single penetrating arteries at different depths (∼800 μm, layers I to V) of the frontal cortex, and examined changes in the diameter during focal electrical stimulation of the NBM (0.5 ms at 30 to 50 μA and 50 Hz) and hypercapnia (3% CO2 inhalation). Stimulation of the NBM caused diameter of penetrating arteries to increase by 9% to 13% of the prestimulus diameter throughout the different layers of the cortex, except at the cortical surface and upper part of layer V, where the diameter of penetrating arteries increased only slightly during NBM stimulation. Hypercapnia caused obvious dilation of the penetrating arteries in all cortical layers, including the surface arteries. The diameters began to increase within 1 second after the onset of NBM stimulation in the upper cortical layers, and later in lower layers. Our results indicate that activation of the NBM dilates cortical penetrating arteries in a layer-specific manner in magnitude and latency, presumably related to the density of cholinergic nerve terminals from the NBM. 相似文献
50.
H Iwase A Tanaka Y Hiki T Kokubo T Sano I Ishii-Karakasa K Toma Y Kobayashi K Hotta 《Journal of chromatography. B, Biomedical sciences and applications》1999,728(2):175-183
Immunoglobulin A1 (IgA1) from normal human serum is known to have O-linked sugar chains, sialylated Galbeta1,3GalNAc, in the hinge portion. In order to reduce the microheterogenity of the sugar chain, the hinge glycopeptide prepared from IgA1 was sequentially treated with neuraminidase and beta-galactosidase. The asialo-, agalacto-hinge glycopeptide (HGP-SG) composed of a 33-mer peptide (HP33) and N-acetylgalactosamine (GalNAc) residues was obtained. The HGP-SG was separated into three major peaks, A, B and C, by high-performance liquid chromatography (HPLC). Each glycopeptide fraction was further separated by capillary electrophoresis (CE). Peaks A, B and C with HPLC abundantly contained HP33 bearing five and six N-acetylgalactosamine residues (HGP33-5,6GN), HGP33-4,5GN and HGP33-3,4GN, respectively. Among these glycopeptide peaks, only the HGP33-5GN peak was partly split into two peaks based on the CE analysis - HGP33-5GN-alpha and -beta. The glycopeptide, HGP25-5GN shortened by the thermolysin digest of HGP33-SG was also well separated into the alpha and beta forms by CE analysis. No differences in their mass and peptide portion were observed between HGP25-5GN-alpha and -beta. Therefore, the obtained result might indicate that HGP25-5GN-alpha was an isomer of HGP25-5GN-beta differing in its stereospecific structure of the peptide portion and/or the attachment site of the GalNAc residue. 相似文献