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91.
Yazawa T Uesaka M Inaoka Y Mizutani T Sekiguchi T Kajitani T Kitano T Umezawa A Miyamoto K 《Endocrinology》2008,149(4):1786-1792
We have shown previously that Cyp11b1, an 11beta-hydroxylase responsible for glucocorticoid biosynthesis in the adrenal gland, was induced by cAMP in androgen-producing Leydig-like cells derived from mesenchymal stem cells. We found that Cyp11b1 was induced in male Leydig cells, or female theca cells, when human chorionic gonadotropin was administered in immature mice. Expression of Cyp11b1 in rodent gonads caused the production of 11-ketotestosterone (11-KT), a major fish androgen, which induces male differentiation or spermatogenesis in fish. As in teleosts, plasma concentrations of 11-KT were elevated in human chorionic gonadotropin-treated mice. In contrast to teleosts, however, plasma concentrations of 11-KT were similar in both sexes, despite levels of testosterone, a precursor substrate, being about 20 times higher in male mice. Because expression of 11beta-hydroxysteroid dehydrogenase type 2, was much higher in the mouse ovary than in the testis, conversion of testosterone into 11-KT may occur more efficiently in the ovary. In a luciferase reporter system that was responsive to and activated by androgens, 11-KT efficiently activated mammalian androgen receptor-mediated transactivation. Our results suggest that the androgen metabolic pathway is conserved between teleosts and mammals, despite sexual dominance and reproductive functions of 11-KT being altered during evolution. 相似文献
92.
Tsuyoshi Kitanishi Yoshinari Aimi Hiroya Kitano Mikio Suzuki Hiroshi Kimura Atsushi Saito Takeshi Shimizu Ikuo Tooyama 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2013,46(5):145-152
We previously discovered a splice variant of choline acetyltransferase (ChAT) mRNA, and designated the variant protein pChAT because of its preferential expression in peripheral neuronal structures. In this study, we examined the immunohistochemical localization of pChAT in rat cochlea and compared the distribution pattern to those of common ChAT (cChAT) and acetylcholinesterase. Some neuronal cell bodies and fibers in the spiral ganglia showed immunoreactivity for pChAT, predominantly the small spiral ganglion cells, indicating outer hair cell type II neurons. In contrast, cChAT- and acetylcholinesterase-positive structures were localized to fibers and not apparent in ganglion cells. After ablation of the cochlear nuclei, many pChAT-positive cochlear nerve fibers became clearly visible, whereas fibers immunopositive for cChAT and acetylcholine esterase disappeared. These results suggested that pChAT and cChAT are localized in different systems of the rat cochlea; pChAT in the afferent and cChAT in the efferent structures. 相似文献
93.
Hiroyuki Oshiumi Kenji Funami Hussein H. Aly Misako Matsumoto Tsukasa Seya 《Archivum immunologiae et therapiae experimentalis》2013,61(2):127-138
Acute hepatitis C virus (HCV) infection evokes several distinct innate immune responses in host, but the virus usually propagates by circumventing these responses. Although a replication intermediate double-stranded RNA is produced in infected cells, type I interferon (IFN) induction and immediate cell death are largely blocked in infected cells. In vitro studies suggested that type I and III IFNs are mainly produced in HCV-infected hepatocytes if the MAVS pathway is functional, and dysfunction of this pathway may lead to cellular permissiveness to HCV replication and production. Cellular immunity, including natural killer cell activation and antigen-specific CD8 T-cell proliferation, occurs following innate immune activation in response to HCV, but is often ineffective for eradication of HCV. Constitutive dsRNA stimulation differs in output from type I IFN therapy, which has been an authentic therapy for patients with HCV. Host innate immune responses to HCV RNA/proteins may be associated with progressive hepatic fibrosis and carcinogenesis once persistent HCV infection is established in opposition to the IFN system. Hence, innate RNA sensing exerts pivotal functions against HCV genome replication and host pathogenesis through modulation of the IFN system. Molecules participating in the RIG-I and Toll-like receptor 3 pathways are the main targets for HCV, disabling the anti-viral functions of these IFN-inducing molecules. We discuss the mechanisms that abolish type I and type III IFN production in HCV-infected cells, which may contribute to understanding the mechanism of virus persistence and resistance to the IFN therapy. 相似文献
94.
Azusa Maruyama Shoichi Tokumoto Hiroshi Yamaguchi Yusuke Ishida Tsukasa Tanaka Kazumi Tomioka Masahiro Nishiyama Kyoko Fujita Daisaku Toyoshima Hiroaki Nagase 《Brain & development》2021,43(4):548-555
IntroductionChildren with either febrile seizure or acute encephalopathy exhibit seizures and/or impaired consciousness accompanied by fever of unknown etiology (SICF). Among children with SICF, we previously reported those who have refractory status epilepticus or prolonged neurological abnormalities with normal AST levels are at a high risk for the development of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), considered to be caused by excitotoxicity. Non-convulsive seizures (NCS) are common in critically ill children and cause excitotoxic neuronal injury. The aim of this study was to elucidate the prevalence of NCS in the acute phase of children at a high risk for developing AESD and the relationship between NCS in the acute phase and neurological outcomes.MethodsWe studied 137 children with SICF at a high risk for developing AESD and who underwent continuous electroencephalogram monitoring (cEEG) upon admission to a tertiary pediatric care center at Hyogo Prefectural Kobe Children’s Hospital between October 2007 and August 2018. Patient characteristics and outcomes were compared between patients with NCS and without NCS.ResultsOf the 137 children, NCS occurred in 30 children; the first NCS were detected in cEEG at the beginning in 63.3%, during the first hour in 90%, and within 12 h in 96.7%. Neurological sequelae were more common in NCS patients (20.0%) than in non-NCS patients (1.9%; p = 0.001). Five in 30 NCS patients (16.7%) and 3 in 107 non-NCS patients (2.8%) developed AESD (p = 0.013).ConclusionThe occurrence of NCS is associated with subsequent neurological sequelae, especially the development of AESD. 相似文献
95.
Hideaki Kashima Tsukasa Ikemura Naoyuki Hayashi 《European journal of applied physiology》2013,113(4):1035-1041
We have previously reported the unique regional responses of facial skin blood flow (SkBF) to oral application of the basic tastes without simultaneous systemic circulatory changes. In the present study, we determined whether a systemic circulatory challenge due to sympathetic activation induces regional differences in facial SkBF by observing the responses in facial SkBF and blood pressure to a 2-min cold pressor test (CPT) and static handgrip exercise (HG) by right hand in 20 healthy subjects. The CPT significantly increased SkBF in the forehead, eyelid, cheek, upper lip and lower lip by 6 ± 2 to 8 ± 2 % (mean ± SEM) as compared to resting baseline, with a significant simultaneous increase (13 ± 2 %) in mean arterial pressure (MAP), whereas it significantly decreased the SkBF in the nose by 5 ± 2 %. The HG significantly increased SkBF in the forehead, cheek and lower lip by 6 ± 3 to 10 ± 3 %, with a significant simultaneous increase in MAP (13 ± 2 %), while it induced no significant change in the other regions. Increases in SkBF were greater in the right than left cheek during CPT. These results demonstrate that a systemic circulatory challenge via sympathetic activation elicits regional differences in the facial SkBF response. 相似文献
96.
97.
Norihiro Nishida Tsukasa Kanchiku Junji Ohgi Kazuhiko Ichihara Xian Chen Toshihiko Taguchi 《中国神经再生研究》2015,10(11):1869-1873
No reports have described experiments designed to determine the strength characteristics of spinal nerve roots and rami radiculares for the purpose of explaining the complexity of symptoms of medullary cone lesions and cauda equina syndrome. In this study, to explain the pathogenesis of cauda equina syndrome, monoaxial tensile tests were performed to determine the strength characteristics of spinal nerve roots and rami radiculares, and analysis was conducted to evaluate the stress-strain relationship and strength characteristics. Using the same tensile test device, the nerve root and ramus radiculares isolated from the spinal cords of pigs were subjected to the tensile test and stress relaxation test at load strain rates of 0.1, 1, 10, and 100 s-1 under identical settings. The tensile strength of the nerve root was not rate dependent, while the ramus radiculares tensile strength tended to decrease as the strain rate increased. These findings provide important insights into cauda equina symptoms, radiculopathy, and clinical symptoms of the medullary cone. 相似文献
98.
Tetsuro Sohda Takayuki Hanano Hisanori Miyamoto Yoko Kitano Kaoru Iwata Masanori Yokoyama Makoto Irie Yasuaki Takeyama Satoshi Shakado Shotaro Sakisaka 《Hepatology International》2008,2(2):258-261
An 80-year-old man was admitted to our hospital because of the rupture of the liver. Laboratory data showed iron-deficiency
anemia, although there was no liver dysfunction. A computed tomography scan showed large liver tumor with intraperitoneal
hemorrhage, and since a serum level of α-fetoprotein (AFP) was extremely high, we initially suspected a rupture of hepatocellular
carcinoma (HCC). Transarterial embolization was performed to stop bleeding from the tumor, followed by an endoscopic examination
that revealed advanced gastric cancer. Histological analysis revealed that both the gastric and the hepatic tumors were moderately
to poorly differentiated adenocarcinoma, as well as that both tumors were immunohistochemically positive for AFP. Finally,
we diagnosed AFP-producing gastric cancer associated with liver metastasis. Rupture of metastatic liver cancer is rare, and
accordingly, distinction from HCC is important, particularly for the cases of AFP-producing gastric cancer. 相似文献
99.
Effects of maternal subtotal nephrectomy on the development of the fetal kidney: A morphometric study 下载免费PDF全文
Tomohiro Kondo Yoko Kitano‐Amahori Hiroaki Nagai Masaki Mino Ai Takeshita Ken Takeshi Kusakabe Toshiya Okada 《Congenital anomalies》2015,55(4):178-182
The present study was designed to explore if maternal subtotal (5/6) nephrectomy affects the development of fetal rat kidneys using morphometric methods and examining whether there are any apoptotic changes in the fetal kidney. To generate 5/6 nephrectomized model rats, animals underwent 2/3 left nephrectomy on gestation day (GD) 5 and total right nephrectomy on GD 12. The fetal kidneys were examined on GDs 16 and 22. A significant decrease in fetal body weight resulting from maternal 5/6 nephrectomy was observed on GD 16, and a significant decrease in fetal renal weight and fetal body weight caused by maternal nephrectomy was observed on GD 22. Maternal 5/6 nephrectomy induced a significant increase in glomerular number, proximal tubular length, and total proximal tubular volume of fetuses on GD 22. Maternal 5/6 nephrectomy resulted in an increase in the number of apoptotic cells in the metanephric mesenchyme of the kidney on GD 16, and in the collecting tubules on GD 22. These findings suggest that maternal 5/6 nephrectomy stimulates the development of the fetal kidney while suppressing fetal growth. 相似文献
100.
Prevention of recurrence of esophageal varices after endoscopic injection sclerotherapy with ethanolamine oleate 总被引:2,自引:0,他引:2
Endoscopic injection sclerotherapy was given to 155 patients with esophageal varices mainly related to non-alcoholic liver cirrhosis. The formation of a superficial ulcer in the lower esophagus was achieved in 141 (91.0%) of the 155 patients, with an average of 4.1 sessions of endoscopic injection sclerotherapy during an average time of 4.9 weeks. The average volume of 5% ethanolamine oleate sclerosant used was 24.8, 19.2, 12.3 and 6.5 ml for the initial to fourth sessions of endoscopic injection sclerotherapy, respectively. For 14 patients, a sufficient number of sessions of endoscopic injection sclerotherapy could not be given: 10 early deaths (5 hepatoma, 4 liver failure and 1 gastric bleeding), and 4 refused further sessions. When the esophageal mucosa had been eliminated and a superficial ulcer had formed, episodes of recurrent bleeding or recurrence of esophageal varices were nil over a median follow-up of 14.6 months, with a range of 1 to 27 months. In seven patients, bleeding recurred before elimination of the mucosa could be achieved, but these bleeding episodes were well controlled with an additional session of endoscopic injection sclerotherapy. At the time of analysis, there were 36 deaths (20 hepatoma, 14 liver failure and 2 gastric bleeding) among these 155 patients. Thus, the mean follow-up was 16.3 months (range: 7 to 27 months) in the 119 survivors, with no recurrence of the varices. We propose that removal of the esophageal mucosa may well be the endpoint of repeated endoscopic injection sclerotherapy in the management of patients on injection sclerotherapy. 相似文献