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101.
102.
Sakabe K Fukuda N Nada T Shinohara H Tamura Y Wakatsuki T Nishikado A Oki T 《Japanese heart journal》2003,44(3):385-393
Although atrial fibrillation is a common arrhythmia, especially in the elderly, little is known about age-related changes in the electrophysiologic properties of the atrium. The aim of this study was to analyze the effect of aging on atrial vulnerability to atrial fibrillation. An electrophysiologic study was performed in 45 patients with no history of atrial fibrillation, Wolff-Parkinson-White syndrome, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiologic function (15 females; mean age, 52 +/- 18 years; range, 14 to 84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation (A2/A1 x 100), effective refractory period, wavelength index (ERP/A2), and inducibility of atrial fibrillation. Atrial fibrillation was induced in 9 patients. Percent maximum atrial fragmentation was greater (176 +/- 36 vs 137 +/- 26%, P < 0.001) and wavelength index was shorter (2.4 +/- 0.4 vs 3.2 +/- 0.9, P < 0.01) in the patients with than without inducible atrial fibrillation. However, age was similar in patients with and without inducible atrial fibrillation (47 +/- 11 vs 53 +/- 19 years, P = 0.36). Percent maximum atrial fragmentation and effective refractory period directly correlated with age (r = 0.32, P < 0.05 and r = 0.45, P < 0.001, respectively). On the other hand, wavelength index (3.1 +/- 0.9) did not correlate with age (r = -0.05, P = 0.77). This study suggests that the mechanism triggering atrial fibrillation may be very well different between older and younger patients with atrial fibrillation, because younger patients have no marked substrate for atrial fibrillation. 相似文献
103.
104.
Noshiro M Kusugami K Sakai T Imada A Ando T Ina K Nobata K Morise K Kaneko H Ito M Nishio Y 《Scandinavian journal of gastroenterology》2000,35(5):482-489
BACKGROUND: Although increased levels of interleukin (IL)-8 are known to be associated with infiltration of neutrophils in the gastric mucosa with Helicobacter pylori infection, no study has investigated the relationship between local IL-8 levels and neutrophil infiltration in the duodenal mucosa of patients with duodenal ulcer (DU). METHODS: Duodenal mucosal biopsy specimens with and without gastric metaplasia (GM) were obtained from patients with DU and controls with an endoscopic methylene blue (MB) staining method. Levels of IL-8 secreted in the organ cultures of biopsy specimens were measured with an enzyme-linked immunosorbent assay. The number of myeloperoxidase-positive neutrophils infiltrating the lamina propria was determined in immunohistochemically stained tissue sections. RESULTS: Histologic assessment showed that there was a strong correlation between the absence of endoscopic MB staining and the extent of GM. The levels of IL-8 in both duodenal and antral mucosal tissues were significantly higher in patients with H. pylori infection than in those without infection. In patients with DU the duodenal mucosal tissues with GM (MB-unstained mucosa) showed significantly higher levels of IL-8 than those without GM (MB-stained mucosa) or the antral mucosa. The number of neutrophils showed similar variations among DU and control patients with a positive correlation with IL-8 activity. The levels of IL-8 and the number of neutrophils decreased after H. pylori eradication in both duodenal and antral mucosal tissues, and these changes were more remarkable in the duodenal mucosal tissues with GM. CONCLUSIONS: Increased IL-8 activity in the duodenal mucosa with GM may be important for ulcerogenesis in H. pylori-positive DU patients. 相似文献
105.
106.
Maegawa H Obata T Shibata T Fujita T Ugi S Morino K Nishio Y Kojima H Hidaka H Haneda M Yasuda H Kikkawa R Kashiwagi A 《Diabetologia》1999,42(2):151-159
Summary A newly synthesized antidiabetic agent, JTT-501 is an isoxazolidinedione rather than a thiazolidinedione. An oral dose of
JTT-501 (100 mg · kg–1· day–1) given to 12-week-old male Zucker fatty rats for 7 days led to the amelioration of both hyperinsulinaemia (40 % of non-treated)
and hypertriglyceridaemia (23 % of non-treated) as well as a 2.4-fold increased insulin sensitivity as determined by a euglycaemic
insulin clamp. In our study, we further evaluated the acute effect of JTT-501 on both the glucose infusion rates (GIR) and
insulin signalling in skeletal muscle. Male Sprague-Dawley (SD) rats aged 10 weeks were injected intravenously with JTT-501
(5 mg/kg) and then a euglycaemic insulin clamp was initiated and glucose infusion rates monitored for 150 min. We found that
this treatment increased the glucose infusion rate by 33 % during the last 30 min in SD rats. After the clamp had been initiated
for 30 min, the insulin-stimulated phosphatidylinositol 3-kinase (PI3-kinase) activities co-immunoprecipitated with insulin
receptor substrate 1 (IRS-1) were also enhanced, resulting in increased glycogen synthase activities in the soleus muscles.
Treatment with JTT-501 also enhanced the phosphorylation of insulin receptors and insulin receptor-substrate 1 rapidly as
well as the phosphatidylinositol 3-kinase activities, which were stimulated by a bolus injection of insulin. Similarly, JTT-501
stimulated the glucose infusion rate by 30 % and enhanced insulin signalling in Zucker fatty rats. In conclusion, a newly
developed isoxazolidinedione, JTT-501, rapidly potentiates the insulin sensitivity of skeletal muscle by enhancing insulin
signalling and could be useful for the treatment of insulin-resistant diabetic subjects. [Diabetologia (1999) 42: 151–159]
Received: 2 June 1998 and in final revised form: 2 October 1998 相似文献
107.
Emma Tabe Eko Niba Hisahide Nishio Yogik Onky Silvana Wijaya Poh San Lai Takenori Tozawa Tomohiro Chiyonobu Misaki Yamadera Kentaro Okamoto Hiroyuki Awano Yasuhiro Takeshima Toshio Saito Masakazu Shinohara 《Brain & development》2021,43(2):294-302
BackgroundSpinal muscular atrophy (SMA) is a neuromuscular disease caused by homozygous deletion of SMN1 exons 7 and 8. However, exon 8 is retained in some cases, where SMN2 exon 7 recombines with SMN1 exon 8, forming a hybrid SMN gene. It remains unknown how the hybrid SMN gene contribute to the SMA phenotype.MethodWe analyzed 515 patients with clinical suspicion for SMA. SMN1 exons 7 and 8 deletion was detected by PCR followed by enzyme digestion. Hybrid SMN genes were further analyzed by nucleotide sequencing. SMN2 copy number was determined by real-time PCR.ResultsSMN1 exon 7 was deleted in 228 out of 515 patients, and SMN1 exon 8 was also deleted in 204 out of the 228 patients. The remaining 24 patients were judged to carry a hybrid SMN gene. In the patients with SMN1 exon 7 deletion, the frequency of the severe phenotype was significantly lower in the patients with hybrid SMN gene than in the patients without hybrid SMN gene. However, as for the distribution of SMN2 exon 7 copy number among the clinical phenotypes, there was no significant difference between both groups of SMA patients with or without hybrid SMN gene.ConclusionHybrid SMN genes are not rare in Japanese SMA patients, and it appears to be associated with a less severe phenotype. The phenotype of patients with hybrid SMN gene was determined by the copy number of SMN2 exon 7, as similarly for the patients without hybrid SMN gene. 相似文献
108.
Tomoko Takemoto Ryo Kaetsu Machiko Hanayama Yuuichi Ishiyama Masayuki Sadamura Kensuke Nishio Mariko Tsunoda Masatake Asano Mitsuru Motoyoshi 《International journal of medical sciences》2021,18(8):1746
The aim of this study was to examine the acid-electrolyzed functional water (FW)-mediated cytokine release in an oral squamous cell carcinoma-derived cell line (OSCC) following treatment with FW. FW is generated by the electrolysis of a sodium chloride solution and accelerate the burn wound healing. To elucidate the underlying mechanisms, the cytokine/chemokine secretion profile of HSC3 cells was examined using a cytokine array. FW treatment significantly induced interleukin (IL)-1α secretion, which was confirmed by enzyme-linked immunosorbent assay. Subsequently, the HSC3 cells were pre-treated with cycloheximide (CHX) for 1 h prior to FW stimulation to determine whether the augmented IL-1α secretion was due to enhanced protein synthesis. CHX pre-treatment did not affect IL-1α secretion suggesting that the secreted IL-1α might have been derived from intracellular storage sites. The amount of IL-1α in the cell lysate of the FW-treated HSC3 cells was significantly lower than that of the non-treated cells. Immunofluorescence staining using a polyclonal antibody against full-length IL-1α revealed a drastic reduction in IL-1α inside the FW- treated cells. IL-1α is synthesized in its precursor form (pIL-1α) and cleaved to produce pro-piece and mature IL-1α (ppIL-1α and mIL-1α) inside the cells. In the present study, only pIL-1α was detected within the HSC3 cells in its resting state. However, FW stimulation resulted in the release of the 33 kDa and two other smaller forms (about 19 kDa) of the protein. These results indicates that FW treatment induces IL-1α secretion, a typical alarmin, from the intracellular storage in OSCC cells. 相似文献
109.
Joo Manoel Rossi Neto Antonio Sergio Tebexreni Alexandre Novakoski F. Alves Floriana Bertini Abreu Priscilla Ayumi Nishio Mauricio Cruz Thomazi Ivana Antelmi Paola Emanuela P. Smanio 《Arquivos brasileiros de cardiologia》2020,115(3):468
Background The most widely used data for cardiorespiratory fitness (CRF) referrals are from the Cooper Clinic, which uses calculated maximal oxygen uptake (VO2max) values.Objective To develop CRF values from cardiopulmonary exercise testing (CPX) in a Brazilian population with high socioeconomic level and free of structural heart disease. VO2max testing results were compared with the Cooper Clinic and FRIEND Registry data.Methods CPX data from consecutive individuals between January 1,2000, and May 31,2016 were used in this study. Inclusion criteria were: VO2max by a pre-specified definition. We built a CRF chart according to VO2max percentiles: very poor (≤20%), poor (20-40%), fair (40-60%), good (60-80%), excellent (80-90%), and superior (≥90%). Kappa correlation was used to analyze our data in comparison with that of the other two databases. Statistical tests with p<0.005 were considered significant.Results Final cohort included 18,186 tests: 12,552 men, 5,634 women (7–84 years). The most recurrent response was “good” (20.2%). There was a mean difference in weight, height, body mass index (BMI), and age in the CRF chart. An inverse correlation existed between VO2max and age, weight, and BMI. Using a linear regression and these variables, a predictive equation was developed for VO2max. Our findings differed from that of the other databases.Conclusion We developed a classification for CRF and found higher values in all classification ranges of functional capacity in contrast to the Cooper Clinic and FRIEND Registry. Our findings offer a more accurate interpretation of ACR in this large Brazilian population sample when compared to previous standards based on the estimated VO2max. (Arq Bras Cardiol. 2020; 115(3):468-477) 相似文献