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91.
Hiroshi Wakabayashi Junichi Taki Anri Inaki Tomo Hiromasa Koichi Okuda Takayuki Shibutani Kazuhiro Shiba Seigo Kinuya 《Molecular imaging and biology》2018,20(4):544-550
Purpose
Ultra-high resolution single-photon emission computed tomography (SPECT) system, using multiple pinhole collimators, has been applied to the imaging of small rodents. We aimed to compare the myocardial infarction (MI) area on quantitative perfusion single-photon emission computed tomography (QPS; Cedars-Sinai Medical Center, USA) with that on high-resolution autoradiography in rat model to determine the accuracy of perfusion defect measurement by QPS.Procedures
After thoracotomy, rats (n?=?9) had their left coronary arteries occluded and reperfused before injection with 185 MBq [99mTc] methoxyisobutylisonitrile ([99mTc]MIBI) for SPECT and autoradiography. Healthy rats (n?=?28) were similarly scanned to create a normal database on which to base QPS. The MI area on SPECT images was analysed automatically by QPS software. For the autoradiography images, regions of interest for MI were set at 1 mm intervals.Results
In normal rats, [99mTc]MIBI accumulated throughout the left ventricles, and a polar map of ventricular perfusion showed the lowest and highest uptakes in the inferior (68 %?±?4 %) and anterior (92 %?±?5 %) walls, respectively. In the rat MI model, the percentage of polar map with reduced [99mTc]MIBI uptake correlated strongly with the percentage of left ventricle with MI on autoradiography (r2?=?0.90).Conclusions
QPS can quantitatively evaluate MI severity on myocardial perfusion images in rats, with comparable results to autoradiography. This widely available software could promote the development of new techniques for analysing cardiac images in small animals.92.
93.
Chisato Onizuka Yuki Niimi Motohiko Sato Junichi Sugenoya 《Environmental health and preventive medicine》2015,20(4):262-270
Objectives
High tolerance to postural changes was examined in nurses.Methods
Twelve female nurses and 12 healthy controls underwent a 70° head-up tilt (HUT) test for 10 min. Blood pressure (BP), heart rate (HR), pulse pressure, and hormone levels were measured. Baroreceptor sensitivity (BRS) was calculated using a sequence technique.Results
HR increased during HUT in both subject groups, with no difference between groups. Systolic BP was rapidly increased by HUT in both subject groups, and was higher in the nurse group than in the control group during the first 2 min of HUT. Pulse pressure decreased during 1–2.5 min of HUT in the control group, but there was no decrease in the nurse group. BRS was decreased by HUT in the nurse group, while it tended to be decreased in the control group. Both during baseline and HUT, BRS was lower in the nurse group than in the control group. Plasma noradrenaline increased with HUT, and the increase was greater in the nurse group than in the control group.Conclusions
Although nurse subjects had a lower BRS during HUT than control subjects, they were able to effectively maintain BP during HUT, suggesting that nurse subjects had higher orthostatic tolerance. The better maintenance of BP in nurse subjects appeared to be associated with a compensatory mechanism other than the arterial baroreflex and/or a hemodynamic mechanism. 相似文献94.
Junya Sato Hiroyuki Matsubayashi Hirotoshi Ishiwatari Tatsunori Satoh Junichi Kaneko Kazuma Ishikawa Masao Yoshida Kohei Takizawa Yohei Yabuuchi Yoshihiro Kishida Kenichiro Imai Kinichi Hotta Katsuhiko Uesaka Keiko Sasaki Hiroyuki Ono 《Internal medicine (Tokyo, Japan)》2021,60(5):739
We herein report a unique form of autoimmune pancreatitis (AIP) spreading along the main pancreatic duct (MPD). A 70-year-old man was referred for a small lesion at the pancreatic neck, accompanying an adjacent cyst and dilated upstream MPD. Four years earlier, health checkup images had shown a pancreatic cyst but no mass lesion. Endoscopic ultrasonography showed a contrast-enhanced, tumorous lesion, mainly occupying the MPD. With a preoperative diagnosis of ductal neoplasms mainly spreading in the MPD, Whipple''s resection was performed. The resected specimens showed MPD periductitis with IgG4-related pathology, indicating type 1 AIP. Clinicians should practice caution concerning the various AIP forms. 相似文献
95.
Kayoko Kasuya Yusuke Kawamura Masahiro Kobayashi Junichi Shindoh Yuta Kobayashi Akira Kajiwara Soichi Iritani Shunichiro Fujiyama Tetsuya Hosaka Satoshi Saitoh Hitomi Sezaki Norio Akuta Fumitaka Suzuki Yoshiyuki Suzuki Kenji Ikeda Yasuji Arase Yuichiro Eguchi Masaji Hashimoto Hiromitsu Kumada 《Internal medicine (Tokyo, Japan)》2021,60(3):345
Objective A survival benefit was demonstrated for ramucirumab (RAM) in patients with unresectable hepatocellular carcinoma (uHCC) and α-fetoprotein (AFP) concentrations ≥400 ng/mL who had previously received sorafenib (SOR). However, it is unclear whether RAM has a similar efficacy in patients with uHCC that progresses after lenvatinib (LEN) treatment. This study aimed to evaluate the early anti-tumor response to RAM as a second-line treatment for advanced uHCC after LEN treatment. Methods We retrospectively assessed the efficacy and safety of RAM at 6 weeks after initiation. The therapeutic effects were evaluated according to the Response Evaluation Criteria in Solid Tumors version 1.1. Patients We evaluated 7 patients with uHCC who received RAM as a second- or third-line treatment after LEN failure. Results The disease control rate (DCR) was 28.6% (2 of 7 patients). After the initiation of RAM, a rapid disease progression resulted in 1 patient death after 19 days. The median progression-free survival (PFS) was 41 days. There were no grade 3 or 4 treatment-related adverse events. At 6 weeks, there was no deterioration in the modified albumin-bilirubin (mALBI) grade. In patients with an imaging response of stable disease (SD), the rate of AFP production decreased from the baseline. Conclusion RAM may have a therapeutic potential for the suppression of uHCC progression in patients previously treated with LEN, as well as for maintaining the liver function during treatment. Evaluating the AFP trends may therefore be useful for predicting RAM effectiveness. 相似文献
96.
Kanako Terakawa Naoki Sawa Hiroki Mizuno Akinari Sekine Noriko Hayami Daisuke Ikuma Masahiro Kawada Rikako Hiramatsu Keiichi Sumida Masayuki Yamanouchi Eiko Hasegawa Tatsuya Suwabe Junichi Hoshino Keiichi Kinowaki Kenichi Ohashi Takeshi Fujii Yoshifumi Ubara 《Internal medicine (Tokyo, Japan)》2021,60(8):1237
A 74-year-old Japanese woman diagnosed with autosomal dominant polycystic kidney disease (ADPKD) was admitted to our institute for the further examination of right-side groin pain developing in the past week. The patient was diagnosed with polymyositis (PM). Diagnostic imaging showed a mass lesion measuring 8 cm and a renal stone in the right kidney. Immediately following surgical resection of the right kidney, the patient''s serum CK decreased to the normal range. A histopathological analysis showed well-differentiated squamous cell carcinoma. In conclusion, this case showed a close relationship between the occurrence of squamous cell carcinoma and the development of PM in an ADPKD patient. 相似文献
97.
Kosuke Tanaka Akiko Sasaki Hideto Egashira Shinichi Teshima Karen Kimura Takashi Nishino Tomohiko Tazawa Junichi Tasaki Chikamasa Ichita Sakue Masuda Kazuya Koizumi Makoto Kako 《Internal medicine (Tokyo, Japan)》2021,60(7):999
We herein report the definitive diagnosis of rectovaginal endometriosis in two cases. Case 1 involved a 46-year-old woman with abdominal pain and hematochezia. The diagnosis after the first and second examinations using lower gastrointestinal (GI) endoscopy was unclear. Differential diagnoses included mucosa-associated lymphoid tissue and colorectal cancer. The third lower GI endoscopy with a targeted biopsy, performed during menstruation, confirmed rectovaginal endometriosis. Case 2 involved a 38-year-old woman with hematochezia. Lower GI endoscopy during menstruation revealed rectovaginal endometriosis. When rectovaginal or bowel endometriosis is suspected, lower GI endoscopy and a targeted biopsy during menstruation can prevent unnecessary surgery. 相似文献
98.
Akt mediates the cross-talk between beta-adrenergic and insulin receptors in neonatal cardiomyocytes
Morisco C Condorelli G Trimarco V Bellis A Marrone C Condorelli G Sadoshima J Trimarco B 《Circulation research》2005,96(2):180-188
Upregulation of the sympathetic nervous system plays a key role in the pathogenesis of insulin resistance. Although the heart is a target organ of insulin, few studies have examined the mechanisms by which beta-adrenergic stimulation affects insulin sensitivity in cardiac muscle. In this study, we explored the molecular mechanisms involved in the regulation of the cross-talk between beta adrenergic and insulin receptors in neonatal rat cardiomyocytes and in transgenic mice with cardiac overexpression of a constitutively active mutant of Akt (E40K Tg). The results of this study show that beta-adrenergic receptor stimulation has a biphasic effect on insulin-stimulated glucose uptake. Short-term stimulation induces an additive effect on insulin-induced glucose uptake, and this effect is mediated by phosphorylation of Akt in threonine 308 through PKA/Ca2+-dependent and PI3K-independent pathway, whereas insulin-evoked threonine phosphorylation of Akt is exclusively PI3K-dependent. On the other hand, long-term stimulation of beta-adrenergic receptors inhibits both insulin-stimulated glucose uptake and insulin-induced autophosphorylation of the insulin receptor, and at the same time promotes threonine phosphorylation of the insulin receptor. This is mediated by serine 473 phosphorylation of Akt through PKA/Ca2+ and PI3K-dependent pathways. Under basal conditions, E40K Tg mice show increased levels of threonine phosphorylation of the beta subunit of the insulin receptor and blunted tyrosine autophosphorylation of the beta-subunit of the insulin receptor after insulin stimulation. These results indicate that, in cardiomyocytes, beta-adrenergic receptor stimulation impairs insulin signaling transduction machinery through an Akt-dependent pathway, suggesting that Akt is critically involved in the regulation of insulin sensitivity. 相似文献
99.
Lewis Blood Group-Related Antigen Expression in Normal Gastric Epithelium, Intestinal Metaplasia, Gastric Adenoma, and Gastric Carcinoma 总被引:6,自引:0,他引:6
Kenji Kobayashi M.D. Junichi Sakamoto M.D. Tsuyoshi Kito M.D. Yoshitaka Yamamura M.D. Takashi Koshikawa M.D. Miyuki Fujita Tadashi Watanabe M.D. Hiroaki Nakazato M.D. 《The American journal of gastroenterology》1993,88(6):919-924
The expression of blood group-related antigens of the Lewis system in normal gastric mucosa, intestinal metaplasia, gastric adenoma, and gastric carcinoma was examined. Ninety-five percent of normal foveolar epithelial samples stained positive for Lewisb antigen, whereas only 10.0% expressed Lewisa antigen. In contrast, intestinal metaplasia specimens had increased Lewisa antigen expression and slightly decreased Lewisb antigen expression. A similar pattern of Lewisa and Lewisb expression was observed in gastric adenomas and intestinal type adenocarcinomas. Lewisx and Lewisy were detected in all normal deep glands, but were not expressed in the majority of intestinal metaplasia specimens. In addition, only 20–40% of gastric adenomas and gastric carcinomas expressed Lewisx and Lewisy antigens. These changes in Lewis antigen expression in intestinal metaplasia, adenomas, and intestinal type adenocarcinomas suggest that altered expression of Lewis blood group-related antigens may correlate with cell transformation processes. 相似文献
100.
The genetic effect of the apoprotein AV gene on the serum triglyceride level in Japanese 总被引:17,自引:0,他引:17
The newly identified apoprotein AV (apoAV) gene was suggested to have a significant effect on triglyceride (TG) metabolism in Caucasians. We studied the genetic effect of this gene on serum TG in a Japanese population. Participants (481 male and 412 female) were recruited at a health examination. A T/C single nucleotide polymorphism called SNP3 in the 5'-region of the apoAV gene was genotyped as described previously. The frequency of the C allele was much greater in Japanese than in Caucasians (0.34 vs. 0.08). The serum TG level in subjects with the TT genotype was significantly lower than the level in those with TC/CC (1.10, 1.25 and 1.21 mmol/l for TT, TC and CC, respectively, P=0.0003 by ANOVA), while there were no significant differences either in the serum total cholesterol or the low- and high-density lipoprotein cholesterol levels among the three genotypes. Multiple regression analysis indicated that SNP3 had a significant independent effect on the serum TG level in Japanese (P<0.0001). This result indicates that polymorphism in the apoAV gene influence serum TG in populations of different ethnicities. 相似文献