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971.
Ken Fukunaga Koji Sawada Yoshihiro Fukuda Yoshika Matoba Kunio Onishi Shin Fukui Makoto Yamamura Masamichi Satomi Takashi Shimoyama 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2002,6(1):93-98
Abstract: An 18‐year‐old woman was treated with leukocytapheresis (LCAP) for her combined ulcerative colitis (UC) and aortitis syndrome (AS). Because a close relationship between these two diseases has been suspected based on their etiological and/or pathological findings, we had hypothesized that LCAP, which has satisfactory effects on inflammatory bowel disease such as UC and Crohn's disease might be effective for both her UC and her AS. After informed consent, LCAP therapy was performed once a week for a total of 7 times. Endoscopic remission of the UC was observed. Even though there were no significant improvements in her subjective symptoms of AS such as side‐neck pain and dizziness, objective evidence of improvement was obtained when the patient's condition was compared before and after LCAP by angiography, angio‐magnetic resonance imaging, and the plethysmogram of her fingertips. These results suggest that LCAP may be valuable as a new adjunct therapy for AS. 相似文献
972.
Li Y Kishimoto I Saito Y Harada M Kuwahara K Izumi T Hamanaka I Takahashi N Kawakami R Tanimoto K Nakagawa Y Nakanishi M Adachi Y Garbers DL Fukamizu A Nakao K 《Endocrinology》2004,145(2):951-958
Myocardial hypertrophy and extended cardiac fibrosis are independent risk factors for congestive heart failure and sudden cardiac death. Before age 50, men are at greater risk for cardiovascular disease than age-matched women. In the current studies, we found that cardiac hypertrophy and fibrosis were significantly more pronounced in males compared with females of guanylyl cyclase-A knockout (GC-A KO) mice at 16 wk of age. These gender-related differences were not seen in wild-type mice. In the further studies, either castration (at 10 wk of age) or flutamide, an androgen receptor antagonist, markedly attenuated cardiac hypertrophy and fibrosis in male GC-A KO mice without blood pressure change. In contrast, ovariectomy (at 10 wk of age) had little effect. Also, chronic testosterone infusion increased cardiac mass and fibrosis in ovariectomized GC-A mice. None of the treatments affected cardiac mass or the extent of fibrosis in wild-type mice. Overexpression of mRNAs encoding atrial natriuretic peptide, brain natriuretic peptide, collagens I and III, TGF-beta1, TGF-beta3, angiotensinogen, and angiotensin converting enzyme in the ventricles of male GC-A KO mice was substantially decreased by castration. The gender differences were virtually abolished by targeted deletion of the angiotensin II type 1A receptor gene (AT1A). Neither castration nor testosterone administration induced any change in the cardiac phenotypes of double-KO mice for GC-A and AT1A. Thus, we suggest that androgens contribute to gender-related differences in cardiac hypertrophy and fibrosis by a mechanism involving AT1A receptors and GC-A. 相似文献
973.
Tetsuya Watanabe Koichi Inoue Kazunori Kashiwase Takanao Mine Keiji Hirooka Ryu Shutta Hiroya Mizuno Yuji Okuyama Yasushi Sakata Shinsuke Nanto 《Journal of electrocardiology》2018,51(6):1111-1115
Background
Atrial fibrillation (AF) and ventricular arrhythmias (VAs) are associated with increased morbidity and mortality. However, data are lacking concerning the association of AF and VAs. This study aimed to clarify the association between AF and VAs and to investigate the effect of amiodarone on the incidence of VAs in patients with implantable cardioverter defibrillators (ICDs).Methods and results
We enrolled 612 patients who had ICDs or who underwent cardiac resynchronization therapy with a defibrillator (CRT-D) and classified them into two groups (sinus rhythm [SR] group, n?=?427; AF group, n?=?185) according to their basal rhythm at enrollment. Patients with paroxysmal AF were grouped into the AF group. The incidence of VAs, i.e., ventricular tachycardia (VT) and ventricular fibrillation (VF), was significantly lower in the AF group than in the SR group (0.54 vs 0.95 episodes/person/year, P?=?0.032). Furthermore, amiodarone use was significantly higher in the AF group than in the SR group (P?=?0.003). Non-use of amiodarone was associated with a significant increase in the occurrence of VT/VF in the two groups. This beneficial suppressive effect of amiodarone on the incidence of VT/VF was present in the AF group regardless of left ventricular ejection fraction (LVEF). However, this effect of amiodarone was present only in patients with LVEF?≥?40% in the SR group.Conclusions
Amiodarone was negatively associated with VT/VF occurrence and was frequently used in ICD/CRT-D patients with AF. VT/VF was controlled by amiodarone in all cases in the AF group but only in patients with an LVEF?≥?40% in the SR group. 相似文献974.
975.
Mutations in hepatitis B virus core regions correlate with hepatocellular injury in Chinese patients with chronic hepatitis B 总被引:2,自引:0,他引:2
Tanaka H Ueda H Hamagami H Yukawa S Ichinose M Miyano M Mimura K Nishide I Zhang BX Wang SW Zhou SO Li BH 《World journal of gastroenterology : WJG》2005,11(30):4693-4696
AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HBV. METHODS: We studied 17 Chinese patients with chronic hepatitis B according to their clinical courses and patterns of the entire core region of HBV. RESULTS: Amino acid changes often appeared in the HBV core region of the HBV gene in patients with high values of alanine aminotransferase (ALT) or with the seroconversion from HbeAg to anti-HBe. The HBV core region with amino acid changes had high frequency sites that corresponded to HLA Ⅰ/Ⅱ restricted recognition epitopes reported by some investigators. CONCLUSION: The core amino acid changes of this study occur due to influence of host immune system. The presence of mutations in the HBV core region seems to be important for predicting the clinical activity of hepatitis B in Chinese patients. 相似文献
976.
Characterization of morphological and cytoskeletal changes in trophoblast cells induced by insulin-like growth factor-I 总被引:8,自引:0,他引:8
Kabir-Salmani M Shiokawa S Akimoto Y Hasan-Nejad H Sakai K Nagamatsu S Sakai K Nakamura Y Hosseini A Iwashita M 《The Journal of clinical endocrinology and metabolism》2002,87(12):5751-5759
IGF-I and IGF-II were appeared to play major roles in the adhesive and migratory events that are considered to be crucial in the implantation process. The purpose of this study was to determine the effects of IGF-I on trophoblast adhesion to extracellular matrix. Trophoblast cells obtained from early gestation at artificial abortion were incubated with the indicated doses of IGF-I at the indicated times. Trophoblast cells were treated with IGF-I in the presence or absence of RGD peptide and an antibody against alpha-subunit of IGF-I receptor (alphaIR3). Morphometric and morphological changes were studied using light and electron microscopy. Furthermore, vinculin, actin stress fibers, phosphorylated focal adhesion kinase (FAK), phosphotyrosine, and paxillin were immunolocalized in trophoblast cells after IGF-I treatment in the presence or absence of alphaIR3. Immunoprecipitation and anti-phosphotyrosine immunoblotting were carried out to detect the phosphorylated FAK and phosphorylated paxillin contents of the IGF-I-treated and untreated trophoblast cells. The results showed that IGF-I promoted trophoblast adhesion to fibronectin substrate in a time- and dose-dependent manner, and addition of RGD peptide and alphaIR3 monoclonal antibody abolished the effects of IGF-I in these cells. Morphological studies exhibited an increase in the lamellipodia formation upon IGF-I treatment, and confocal images of immunofluorescent staining revealed localization of phosphorylated FAK, paxillin, and vinculin at focal adhesions as well as redistribution of actin microfilaments and formation of actin stress fibers inside the cell. Western blotting, using antiphosphotyrosine demonstrated proteins with molecular masses of 125 kDa (FAK) and 68 kDa (paxillin) present in the IGF-I-treated cells, which were lacking in the control groups. In conclusion, these findings suggest that IGF-I can stimulate lamellipodia formation and promote adhesion of trophoblast cells to extracellular matrix by activating their adhesion molecules that must be activated within the implantation window. 相似文献
977.
Platelet-derived growth factor activates protein kinase C epsilon through redundant and independent signaling pathways involving phospholipase C gamma or phosphatidylinositol 3-kinase. 总被引:5,自引:0,他引:5 下载免费PDF全文
S Moriya A Kazlauskas K Akimoto S Hirai K Mizuno T Takenawa Y Fukui Y Watanabe S Ozaki S Ohno 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(1):151-155
Protein kinase C (PKC), a major cellular receptor for tumor-promoting phorbol esters and diacylglycerols (DGs), appears to be involved in a variety of cellular functions, although its activation mechanism in vivo is not yet fully understood. To evaluate the signaling pathways involved in the activation of PKC epsilon upon stimulation by platelet-derived growth factor (PDGF) receptor (PDGFR), we used a series of PDGFR "add-back" mutants. Activation of a PDGFR mutant (Y40/51) that binds and activates phosphatidylinositol 3-kinase (PI 3-kinase) caused translocation of PKC epsilon from the cytosol to the membrane in response to PDGF. A PDGFR mutant (Y1021) that binds and activates phospholipase C gamma (PLC gamma), but not PI 3-kinase, also caused the PDGF-dependent translocation of PKC epsilon. The translocation of PKC epsilon upon stimulation of PDGFR (Y40/51) was inhibited by wortmannin, an inhibitor of PI 3-kinase. Activation of PKC epsilon was further confirmed in terms of PKC epsilon-dependent expression of a phorbol 12-tetradecanoate 13-acetate response element (TRE)-luciferase reporter. Further, purified PKC epsilon was activated in vitro by either DG or synthetic phosphatidylinositol 3,4,5-trisphosphate. These results clearly demonstrate that PKC epsilon is activated through redundant and independent signaling pathways which most likely involve PLC gamma or PI 3-kinase in vivo and that PKC epsilon is one of the downstream mediators of PI 3-kinase whose downstream targets remain to be identified. 相似文献
978.
Mechanical stress-dependent secretion of interleukin 6 by endothelial cells after portal vein embolization: clinical and experimental studies 总被引:6,自引:0,他引:6
Kawai M Naruse K Komatsu S Kobayashi S Nagino M Nimura Y Sokabe M 《Journal of hepatology》2002,37(2):240-246
BACKGROUND/AIMS: Interleukin-6 (IL-6) is an essential early signal in liver regeneration, however, little is known about what triggers IL-6 release. Changes in portal hemodynamics after portal vein embolization (PVE) may contribute to IL-6 release, leading to regeneration of non-embolized lobe.METHODS: In 22 patients who underwent right PVE, the diameters of the left portal branches, liver volumes, and serum concentrations of IL-6, tumor necrosis factor-alpha (TNF-alpha), and hepatocyte growth factor (HGF) were measured. We then studied endothelial cells cultured on an elastic silicone membrane and subjected to continuous uni-axial stretch. Supernatant cytokine concentrations were measured.RESULTS: The diameters of the portal branches increased by 150% after PVE. Serum IL-6 concentrations increased within 3h after PVE. The concentrations of TNF-alpha and HGF remained unchanged. The left lobe volume increased 2 weeks after PVE. The IL-6 concentrations in the supernatant of endothelial cells with stretch stress were higher than that in the non-stretched control group.CONCLUSIONS: These findings indicate that PVE dilates the portal branches in the non-embolized lobe, exposing hepatic vasculature to stretch stress. This hemodynamic change may act as a trigger for IL-6 release from endothelial cells and contribute to the activation of regenerative cascade in the non-embolized lobes. 相似文献
979.
Miyazaki H Noma K Date T Kobayashi A Koga A Kuno M Takeda S Iwano K Seki S Inada K Matsuo S Miyanaga S Abe K Yamane T Sugimoto K Mochizuki S 《Journal of cardiology》2005,45(6):239-246
OBJECTIVES: Atrial septal pacing via a trans-septal breakthrough site within the right atrial septum can shorten global atrial activation time, resulting in significant reduction of recurrence of atrial fibrillation events. This study examined whether this pacing method will lead to resynchronization of atrial contraction and its benefit on hemodynamic function can be maintained for 24 months. METHODS: Thirty patients with atrial fibrillation and delayed atrial conduction were enrolled (17 males, 13 females, mean age 73 +/- 7 years). Trans-septal breakthrough site within the right atrial septum was identified through pacing from the dorsal left atrium. Continuous atrial septal pacing at the trans-septal breakthrough site was performed for 24 months. Time difference (TD) between right and left atrial contractions was measured during atrial septal pacing and sinus rhythm by pulse Doppler echocardiography of the trans-tricuspid (P-At) and mitral (P-Am) blood flows (TD = P-Am - P-At). RESULTS: The atrial lead was screwed near the fossa ovalis in 29 of 30 patients. Atrial septal pacing yielded significantly shorter P wave duration (101.9 +/- 10.4 vs 139.6 +/- 14.7 msec, p < 0.001), leading to significant reduction of TD in atrial contraction (-8.8 +/- 10.0 vs 29.8 +/- 13.6 msec, p < 0.001)as compared to sinus rhythm. Both shorter P wave duration and reduced TD during atrial septal pacing remained statistically significant during the follow-up period as compared to sinus rhythm. Both left atrial diameter and A to E ratio of filling waves at mitral valve were significantly decreased at 12 months and remained decreased at 24 months. CONCLUSIONS: Atrial septal pacing at the trans-septal breakthrough site can resynchronize atrial contraction and results in improved hemodynamic effects during 24 months of follow-up. 相似文献
980.