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991.
Toshiro Ito Nobuyoshi Kawaharada Yoshihiko Kurimoto Tetsuya Koyanagi Takeshi Uzuka Mayuko Uehara Takayuki Hagiwara Yohsuke Yanase Toshiyuki Maeda Tetsuya Higami 《Surgery today》2013,43(9):1019-1024
Purpose
To evaluate the association of previous abdominal aortic aneurysm (AAA) graft replacement with infradiaphragmatic malperfusion in patients with acute aortic dissection.Methods
Between November 2006 and June 2011, 133 patients were referred to our hospital for management of acute aortic dissection. Eight (6.0 %) of these patients had undergone AAA graft replacement prior to the acute aortic dissection. We compared the computed tomography (CT) images of these 8 patients with those of the remaining 125 patients without previous AAA graft replacement, in terms of organ ischemia as a complication induced by acute aortic dissection.Results
Infradiaphragmatic malperfusion from acute aortic dissection was confirmed in four of the eight patients who had undergone AAA graft replacement. Contrasted CT scan images indicated that the main cause of infradiaphragmatic malperfusion was collapse of the true lumen from compression by the false lumen into the suprarenal aorta. Although there was no significant difference between the groups in terms of cerebral ischemia and myocardial ischemia, bilateral leg ischemia and visceral ischemia occurred more frequently in the patients who had undergone AAA graft replacement.Conclusion
Previous AAA graft replacement is a risk factor for infradiaphragmatic malperfusion in patients with acute aortic dissection. 相似文献992.
Keisuke Iwasaki Hiroshi Maeda Isao Shimokawa Masafumi Hayashida Byung Pal Yu Edward J. Masoro Takayoshi Ikeda 《Pathology international》1988,38(9):1119-1130
The influence of age and diet on the ultrastructure of hepatocytes is reported. The following dietary manipulations were investigated: Group 1, fed ad libitum a diet containing 21% protein; Group 2, fed a similar diet but restricted to 60% of the intake of Group 1 from 6 weeks of age onwards; Group 3, restricted from 6 weeks to 6 months of age and thereafter fed ad libitum; Group 4, restriction started at 6 months of age; Group 5, fed ad libitum a diet containing 12.6% protein. In all groups the size of hepatocytes was found not to increase during adult life. The size of hepatocytes in Groups 2 and 4 was the same as or larger than that of the other groups; thus food restriction resulted in a decreased number of hepatocytes. Changes in the structure of some organelles and the accumulation of lipofuscin granules occurred with advancing age and the extent of these age-related changes was less in Groups 2 and 4 than in the other groups. These morphologic findings in conjunction with our previously reported metabolic findings provide a new view of the action of food restriction on the aging process. ACTA PATHOL JPN 38: 1119∼1130, 1988. 相似文献
993.
K. Kawano H. Ono O. Iwashita M. Kurogi T. Haga K. Maeda Y. Goto 《European journal of clinical microbiology & infectious diseases》2012,31(2):119-127
The relationship between human diseases caused by infection with Shiga toxin (Stx)-producing Escherichia coli (STEC) O157 strains and O157 strains isolated from cattle was investigated in an area where stockbreeding is prolific. For
this purpose, the stx genotypes, the molecular epidemiological characteristics of 268 STEC O157 strains including 211 human-origin strains and
57 cattle-origin strains, and clinical manifestations of 210 STEC-infected people were analyzed. Of 211 human-origin strains,
92 strains (44%) were of the stx1/stx2 genotype, and 74 strains (35%) were of the stx2c genotype. Most of the people infected with stx2c genotype strains presented no symptoms or mild symptoms such as slight diarrhea, except for 3 patients with bloody diarrhea.
Of the 57 cattle-origin strains, 27 strains (47%) were of the stx2c genotype and 17 strains (30%) were of the stx1/stx2 genotype. Pulsed-field gel electrophoresis (PFGE) and insertion sequence (IS) analysis demonstrated that 11 isolates (41%)
of the 27 cattle isolates of the stx2c genotype had high homology (>95% identity) with human isolates. These results suggest that some genetic patterns of the stx2c genotype strains might be preserved in cattle or their surrounding environment for several years, and during these periods,
they might have opportunities to infect people through various routes. Because of the mild virulence of the stx2c genotype strains, they seemed to be transmitted asymptomatically from cattle to humans and then spread from person to person.
It may be a public health concern. Further, they occasionally cause severe symptoms in humans; therefore, caution is warranted
for infections by stx2c genotype O157 strains, in addition to stx2-possessing genotype O157 strains. 相似文献
994.
H Tanaka K Muguruma M Ohira N Kubo Y Yamashita K Maeda T Sawada K Hirakawa 《Anticancer research》2012,32(8):3427-3433
Protein-bound polysaccharide K (PSK) is an anticancer agent used for adjuvant therapy against gastric cancer. The aim of this study was to evaluate the effect of PSK on the overall survival of patients with gastric cancer. A total of 254 patients who underwent surgical curative resection were included in this retrospective study. We identified 138 patients who received antimetabolites alone (control group) and 115 patients who received antimetabolites plus PSK (PSK group). In patients with early tumor recurrence, overall survival was significantly better in the PSK group (p=0.023). In patients with pN3 lymph node metastasis, median overall survival was better in the PSK group compared with the control group (p=0.032). Our results suggest that adjuvant immunochemotherapy with PSK increased the overall survival for patients with pN3 and early tumor recurrence. Thus, the combination of PSK with oral chemotherapeutic agents might be suitable for postoperative adjuvant therapy against gastric cancer in patients with lymph node metastases. 相似文献
995.
M. Sakakibara C. Deura S. Minabe Y. Iwata Y. Uenoyama K.‐I. Maeda H. Tsukamura 《Journal of neuroendocrinology》2013,25(3):251-259
Female rats show a gonadotrophin‐releasing hormone (GnRH)/luteinising hormone (LH) surge in the presence of a preovulatory level of oestrogen, whereas males do not because of brain defeminisation during the developmental period by perinatal oestrogen converted from androgen. The present study aimed to identify the site(s) of oestrogen action and the critical period for defeminising the mechanism regulating the GnRH/LH surge. Animals given perinatal treatments, such as steroidal manipulations, brain local implantation of oestradiol (E2) or administration of an NMDA antagonist, were examined for their ability to show an E2‐induced LH surge at adulthood. Lordosis behaviour was examined to compare the mechanisms defeminising the GnRH/LH surge and sexual behaviour. A single s.c. oestradiol‐benzoate administration on either the day before birth (E21), the day of birth (D0) or day 5 (D5) postpartum completely abolished the E2‐induced LH surge at adulthood in female rats, although the same treatment did not inhibit lordosis. Perinatal castration on E21 or D0 partially rescued the E2‐induced LH surge in genetically male rats, whereas castration from E21 to D5 totally rescued lordosis. Neonatal E2 implantation in the anterior hypothalamus including the anteroventral periventricular nucleus (AVPV)/preoptic area (POA) abolished the E2‐induced LH surge in female rats, whereas E2 implantation in the mid and posterior hypothalamic regions had no inhibitory effect on the LH surge. Lordosis was not affected by neonatal E2 implantation in any hypothalamic regions. In male rats, neonatal NMDA antagonist treatment rescued lordosis but not the LH surge. Taken together, these results suggest that an anterior hypothalamic region such as the AVPV/POA region is a perinatal site of oestrogen action where the GnRH/LH regulating system is defeminised to abolish the oestrogen‐induced surge. The mechanism for defeminisation of the GnRH/LH surge system might be different from that of sexual behaviour, in terms of the site(s) of oestrogen action and critical period, as well as the neurotransmitter system involved. 相似文献
996.
Ieiri I Suwannakul S Maeda K Uchimaru H Hashimoto K Kimura M Fujino H Hirano M Kusuhara H Irie S Higuchi S Sugiyama Y 《Clinical pharmacology and therapeutics》2007,82(5):541-547
To investigate the contribution of genetic polymorphisms of SLCO1B1 and ABCG2 to the pharmacokinetics of a dual substrate, pitavastatin, 2 mg of pitavastatin was administered to 38 healthy volunteers and pharmacokinetic parameters were compared among the following groups: 421C/C(*)1b/(*)1b (group 1), 421C/C(*)1b/(*)15 (group 2), 421C/C(*)15/(*)15 and 421C/A(*)15/(*)15 (group 3), 421C/A(*)1b/(*)1b (group 4), 421A/A(*)1b/(*)1b (group 5), and 421C/A(*)1b/(*)15 (group 6). In SLCO1B1, pitavastatin area under plasma concentration-time curve from 0 to 24 h (AUC(0-24)) for groups 1, 2, and 3 was 81.1+/-18.1, 144+/-32, and 250+/-57 ng h/ml, respectively, with significant differences among all three groups. In contrast to SLCO1B1, AUC(0-24) in groups 1, 4, and 5 was 81.1+/-18.1, 96.7+/-35.4, and 78.2+/-8.2 ng h/ml, respectively. Although the SLCO1B1 polymorphism was found to have a significant effect on the pharmacokinetics of pitavastatin, a nonsynonymous ABCG2 variant, 421C>A, did not appear to be associated with the altered pharmacokinetics of pitavastatin. 相似文献
997.
Hiroto Kinoshita Hitomi Nishioka Aya Ikeda Kyoko Ikoma Yoichi Sameshima Hidehisa Ohi Mizuki Tatsuno Junka Kouyama Chiaki Kawamoto Tomohiro Mitsui Yuko Tamura Yu Hashimoto Masashi Nishio Tsuyoshi Ogashiwa Yusuke Saigusa Shin Maeda Hideaki Kimura Reiko Kunisaki Kazuhiko Koike 《Journal of gastroenterology and hepatology》2019,34(11):1929-1939
998.
Effective segmental chemoembolization of advanced hepatocellular carcinoma with tumor thrombus in the portal vein 总被引:12,自引:0,他引:12
Tetsuya Katsumori M.D. Masato Fujita Takeshi Takahashi Osamu Satoh Shigeki Ichijima Toshiyuki Nakamura Hiroyuki Morishita Kohji Ohno Yasuhiko Nakano Tomoho Maeda 《Cardiovascular and interventional radiology》1995,18(4):217-221
Purpose: Evaluate therapeutic results of transcatheter segmental hepatic artery chemo-oily-embolization (segmental TAE) against advanced hepatocellular carcinomas (HCC) accompanied by portal tumor thrombus (PTT).
Methods: Segmental TAE was performed in nine patients with hepatic cirrhosis and advanced HCCs accompanied by PTT. Four subsegmental portal branches were obstructed by PTT in three patients, and two were obstructed in the remaining six patients. TAE was performed into the targeted segmental hepatic artery followed by embolization with gelatin sponge particles.
Results: In one patient undergoing subsequent resection, a marked anticancer effect on the PTT was demonstrated histologically. In the eight other patients who did not undergo subsequent resection, the cumulative survival rates were 67% at 6 months, 44% at 1 year, and 22% at 2 years. No serious complications were noted.
Conclusions: This therapeutic approach is thought to be a useful treatment for HCC with PTT, because it reinforces anticancer effects and can be performed more safely than conventional transcatheter arterial embolization. 相似文献
999.
Proapoptotic effect of proteolytic activation of matrix metalloproteinases by Streptococcus pyogenes thiol proteinase (Streptococcus pyrogenic exotoxin B) 下载免费PDF全文
Tamura F Nakagawa R Akuta T Okamoto S Hamada S Maeda H Kawabata S Akaike T 《Infection and immunity》2004,72(8):4836-4847
Streptococcus pyogenes thiol proteinase, also known as streptococcal pyrogenic exotoxin B (SpeB), has been suggested to be a major virulence factor in S. pyogenes infection. SpeB was reported to induce apoptosis of host cells, but its mechanism of action is not yet fully understood. In this study, we examined the involvement of matrix metalloproteinases (MMPs) in SpeB-induced apoptosis. We first developed a large-scale preparation of recombinant SpeB and precursors of human MMP-9 and -2 (proMMPs) by using Escherichia coli Rosetta (DE3)pLysS and baculovirus-insect cell expression systems, respectively. Treatment with SpeB induced effective proteolytic activation of both proMMP-9 and -2. When RAW264 murine macrophages were incubated with SpeB-activated proMMP-9, the level of tumor necrosis factor alpha (TNF-alpha) in conditioned medium (CM), assessed by an enzyme immunoassay, was elevated. This increase was completely inhibited by addition of the MMP inhibitor SI-27 to the cell culture. The CM also produced marked induction of apoptosis of U937 human monocytic cells. Similarly, soluble Fas ligand (sFasL) was detected in CM of cultures of SW480 cells expressing FasL after treatment with SpeB-activated proMMPs; this CM also induced apoptosis in U937 cells. SpeB had a direct effect as well and caused the release of TNF-alpha and sFasL from the cells. SpeB-dependent production of MMP-9 and -2 and proapoptotic molecules (TNF-alpha and sFasL) was evident in a murine model of severe invasive S. pyogenes infection. These results suggest that SpeB or SpeB-activated MMPs contribute to tissue damage and streptococcal invasion in the host via extracellular release of TNF-alpha and sFasL. 相似文献
1000.
Junji Kozawa Tetsuhiro Kitamura Hitoshi Nishizawa Tetsuyuki Yasuda Norikazu Maeda Michio Otsuki Kohei Okita Hiromi Iwahashi Hideaki Kaneto Tohru Funahashi Akihisa Imagawa Iichiro Shimomura 《Journal of diabetes investigation.》2013,4(2):190-194