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31.
Naohisa Ibuki Kazuhide Yamamoto Kazuhisa Yabushita Nobuaki Okano Ryoichi Okamoto Noriaki Shimada Tomomi Hakoda Motowo Mizuno Toshihiro Higashi Takao Tsuji 《Liver international》2002,22(3):198-204
Abstract: Background/Aims: The molecular mechanism involved in hepatocellular injury in viral hepatitis remains to be clarified. Methods: We investigated the in situ expression of effector molecules of cytotoxic T lymphocytes such as Fas‐ligand (Fas‐L), perforin and Granzyme B (Gr‐B) immunohistochemically in liver tissues from 20 patients with chronic hepatitis B (CHB) and C (CHC). The degree of cell infiltration was analysed semi‐quantitatively and compared with the histological activity index (HAI). Fas‐L was expressed in both CD4 and CD8 T‐cells in the portal tract as well as in the parenchyma. Results: Immunostaining of serial sections demonstrated that mononuclear cells at interface hepatitis and focal necrosis were mainly Fas‐L positive CD8 T‐cells. On the other hand, the expression of perforin or Gr‐B was limited to a few mononuclear cells in the portal tract and parenchyma. Semi‐quantitative analysis showed a positive correlation between HAI and the grade of infiltration of CD8 T‐cells or Fas‐L‐positive cells, while the correlation was not apparent between HAI and the number of Gr‐B positive cells. The expression of these molecules was not different between types of viruses. Conclusions: These results suggest that Fas‐L‐positive CD8 T‐cells play a major role in the pathogenesis of liver cell injury in chronic hepatitis. 相似文献
32.
Toiyama Y Araki T Yoshiyama S Miki C Kusunoki M 《World journal of gastroenterology : WJG》2005,11(43):6888-6890
We report a case of secondary pouchitis, defined as a mucosal inflammatory lesion in the ileal reservoir provoked by pouch-related complication following total colectomy and pouch anal anastomosis, which was successfully treated by salvage surgery- A 20-year-old woman with ulcerative colitis developed acute severe bloody diarrhea following proctocolectomy, ileal pouch-anal anastomosis and diverting ileostomy. She was diagnosed as having a secondary pouchitis mainly caused by a peripouch abscess and partly concerned with the abnormal pouch formation. The remnant rectum and ileal pouch were excised and ileal pouch-anal anastomosis and diverting ileostomy were constructed. The postoperative course was uneventful with no sign of pouchitis. Salvage surgery may be indicated to treat secondary pouchitis when caused by surgery-related complications. 相似文献
33.
Flavia Kazue Ibuki Alyne Simões José Nicolau Fernando Neves Nogueira 《Lasers in medical science》2013,28(3):911-918
The aim of the present study was to analyze the effect of low-power laser irradiation in the antioxidant enzymatic system of submandibular (SMG) and parotid (PG) salivary glands of streptozotocin-induced diabetic rats. The animals were randomly divided into six groups: three diabetic groups (D0, D5, and D20) and three non-diabetic groups (C0, C5, and C20), according to laser dose received (0, 5, and 20 J/cm2, respectively). Areas of approximately 1 cm2 were demarcated in the salivary glands (each parotid and both submandibular glands) and after irradiated according to Simões et.al. (Lasers Med Sci 24:202–208, 2009). A diode laser (660 nm/100 mW) was used, with laser beam spot of 0.0177 cm2. The group treated with 5 J/cm2 laser dose was subjected to irradiation for 1 min and 4 s (total irradiation time) and the group treated with 20 J/cm2 laser dose was subjected to irradiation for 4 min and 16 s. Twenty-four hours after irradiation the animals were euthanized and the salivary glands were removed for biochemical analysis. The total antioxidant values (TA), the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase enzymes were determined. SOD and CAT activities, as well as TA were higher in SMG of irradiated diabetic rats. However, in SMG of non-diabetic rats, laser irradiation decreased TA values and led to an increase in the CAT activity. In addition, there was a decrease in the activity of CAT in PG of diabetic and non-diabetic animals after laser irradiation. According to the results of the present study, low-power laser irradiation can affect the enzymatic antioxidant system of salivary glands of streptozotocin-induced diabetic rats. 相似文献
34.
Diagnosis of gallbladder diseases by contrast-enhanced phase-inversion harmonic ultrasonography 总被引:3,自引:0,他引:3
Inoue T Kitano M Kudo M Sakamoto H Kawasaki T Yasuda C Maekawa K 《Ultrasound in medicine & biology》2007,33(3):353-361
We evaluated the usefulness of contrast-enhanced ultrasonography(US) for detecting and differentiating gallbladder lesions. Contrast-enhanced coded phase-inversion harmonic US was performed on 90 patients with gallbladder abnormalities. After administering Levovist, we observed the gallbladders in real time. Contrast-enhanced coded phase-inversion harmonic ultrasonography was compared with B-mode US and contrast-enhanced computer tomography (CT) with regard to the sensitivity and specificity in depicting the elevated gallbladder lesions. Furthermore, we assessed how the vascular patterns of the elevated gallbladder lesions depicted by contrast-enhanced US correlated with the diagnosis. Contrast-enhanced US efficiently discriminated true lesions from biliary sludge, unlike B-mode US. Consequently, contrast-enhanced US was more specific (100%) than B-mode US (81%), although their sensitivities were similar (98% and 96%, respectively). Contrast-enhanced US was also more sensitive that contrast-enhanced CT (98% versus 79%), although the two methods were equally sensitive (100% versus 95%). We classified the vascular patterns of the abnormalities depicted by contrast-enhanced US in the 90 cases into types 1 to 4, which represent branch-like, heterogeneous, homogeneous, and avascular patterns, respectively. All type 1 and 2 lesions were over 10 mm in size while most (88%) type 3 lesions were 10 mm or less in size. While the majority of carcinomas (86%) were type 1 or 2, three benign lesions also showed these patterns. Thus, the vascular pattern may simply reflect the size of the lesion and therefore its usefulness in diagnosing gallbladder lesions may be limited. Nevertheless, contrast-enhanced US is clearly superior to the other techniques in discriminating biliary sludge from other lesions. 相似文献
35.
Evaluation of gastric motor activity in the elderly by electrogastrography and the (13)C-acetate breath test 总被引:2,自引:0,他引:2
BACKGROUND: Elderly people frequently have symptoms of fullness and appetite loss due to impaired gastric motor activity. These symptoms may cause malnutrition, immunosuppression and other complications. OBJECTIVE: The effects of aging and daily activity on gastric motility in the elderly were investigated by electrogastrography and the (13)C-acetate breath test. METHODS: We enrolled seven active elderly subjects (active elderly group), seven elderly subjects staying at a geriatric facility who had reduced mental and physical capacities (inactive elderly group) and seven healthy young volunteers (young group). Electrogastrography was recorded before and after ingestion of a (13)C-acetate-mixed liquid meal. Expired air was sampled every 10 min after the meal to measure the (13)CO(2) concentration. RESULTS: The ratio of the incidence of the 3-cpm wave (gastric intrinsic frequency) during the postprandial period compared to the fasting state was reduced in both elderly groups compared to young subjects, and the reduction was greater in the inactive elderly than in the active elderly group. The ratio of the amplitude of the peak frequency during the postprandial period to that in the fasting state (power ratio) was also lower in the elderly groups. The time of peak (13)CO(2) expiration was delayed in the active elderly and more so in the inactive elderly group. CONCLUSIONS: Postprandial peristalsis and gastric contractile force are reduced in the elderly, and gastric emptying is delayed indicating a reduction in gastric motor activity. 相似文献
36.
Toshiaki Otsuka Tomoyuki Kawada Masao Katsumata Chikao Ibuki 《Circulation journal》2006,70(3):304-310
BACKGROUND: Increased arterial stiffness has been shown to be associated with coronary heart disease (CHD). However, it remains unclear as to whether the second derivative of the finger photoplethysmogram (SDPTG), a non-invasive method for the assessment of arterial stiffness, is useful for the estimation of risk of CHD in the general population. METHODS AND RESULTS: The SDPTG in 211 subjects (age: 63+/-15 years, range: 21-91 years, 93 males) was recorded without apparent atherosclerotic disorders from a community. The relationship between the SDPTG indices (b/a and d/a) and coronary risk factors (n=211) or the Framingham risk score (n=158, age: 60+/-12 years, range: 30-74 years, 63 males) were analyzed. The SDPTG indices significantly correlated with the Framingham risk score in both genders (b/a; r(male) =0.43, r(female) =0.54 and d/a; r(male) =-0.38, r(female) =-0.58), as well as several coronary risk factors. In the receiver operating characteristics curve analyses, the b/a discriminated high-risk subjects for CHD, who were in the highest quintile of the Framingham risk score in each gender, with a sensitivity and specificity of 0.85 and 0.58 in males and 0.83 and 0.72 in females, respectively. CONCLUSIONS: These results suggest that the SDPTG is useful for the estimation of risk of CHD in the general population. 相似文献
37.
Action mechanism of inhibin in vitro--cycloheximide mimics inhibin actions on pituitary cells 总被引:1,自引:0,他引:1
M Fukuda K Miyamoto Y Hasegawa Y Ibuki M Igarashi 《Molecular and cellular endocrinology》1987,51(1-2):41-50
The effects of inhibin on gonadotropin secretion from cultured rat anterior pituitary cells were examined by using purified porcine follicular fluid (pFF) 32 kDa inhibin. pFF 32 kDa inhibin suppressed the basal FSH secretion as well as cell content of FSH with identical ED50 values (ED50 = 1.0 ng/ml) in a dose-dependent manner, but did not alter either basal secretion or cell content of LH. On the other hand, pretreatment of the pituitary cells with pFF 32 kDa inhibin during the first 3 days resulted in suppression of subsequent LH-RH-stimulated release of both FSH and LH in a dose-dependent manner, indicating that the suppression of LH-RH-stimulated release of LH is one of the intrinsic inhibin actions on pituitary cells. The marked difference between ED50 values for FSH (ED50 = 1.1 ng/ml) and LH (ED50 = 2.5 ng/ml) in the suppression of LH-RH-stimulated release of gonadotropins, together with the fact that the total amount of LH (cell content plus released) after LH-RH stimulation remained unchanged following inhibin treatment suggests that the suppression of LH-RH-stimulated release of LH by inhibin is quite different from that of FSH regarding the action mechanism. Similarly, cycloheximide, an inhibitor of protein biosynthesis, suppressed both basal secretion and cell content of FSH with almost the same ED50 values (ED50 = 22.5 ng/ml) but did not alter either basal secretion or cell content of LH. Cycloheximide also suppressed LH-RH-stimulated release of both FSH and LH, and the ED50 values were different from each other (ED50 = 25.0 ng/ml for FSH and 60.0 ng/ml for LH suppression, respectively). Our finding that cycloheximide completely mimicked the action of inhibin on gonadotropin secretion strongly suggests that LH is quite insensitive to biosynthetic inhibition, and that preferential effects of inhibin or cycloheximide on FSH in appearance may reflect the difference between LH and FSH in susceptibility to biosynthetic inhibition. 相似文献
38.
Hormonal regulation of gonadotropin receptor mRNA in rat ovary during follicular growth and luteinization. 总被引:2,自引:0,他引:2
K Nakamura T Minegishi Y Takakura K Miyamoto Y Hasegawa Y Ibuki M Igarashi 《Molecular and cellular endocrinology》1991,82(2-3):259-263
To investigate the regulation of the follicle-stimulating hormone (FSH) and luteinizing hormone/human chorionic gonadotropin (LH/hCG) receptor genes by gonadotropins, we examined the effect of pregnant mare's serum gonadotropin (PMSG) or PMSG-hCG on the expression of FSH and LH/hCG receptors in rat ovaries. After administration of PMSG, Northern blot analysis using the FSH receptor cDNA probe revealed that a major band of 2400 nucleotides was detected which reached the maximal level on day 3. On the other hand, the level of LH/hCG receptor mRNA, a major mRNA of 5400 nucleotides and minor species of 7500, 3600, 2300 and 1200 nucleotides, increased progressively during 4 days. Treatment with hCG resulted in a decrease of FSH and LH/hCG receptor mRNA levels, and the level of FSH receptor mRNA was completely suppressed. Although the level of LH/hCG receptor mRNA was also suppressed from 3 h to an almost undetectable level at 24 h after hCG injection, it recovered to the control level by 48 h and exceeded this level several fold by 72 h. The reappearance of LH/hCG receptors following desensitization was preceded by an increase in mRNA levels. These studies demonstrate that hormonal regulation of gonadotropin receptor mRNAs on rat ovary reflects the changes in gonadotropin receptor levels. 相似文献
39.
Genomic instability and tissue expression of angiogenic growth factors in sporadic colorectal cancer 总被引:3,自引:0,他引:3
BACKGROUND: Chromosomal instability evidenced by a loss of heterozygosity (LOH) is implicated as a predictor of poor survival in patients with colorectal cancer, whereas microsatellite instability (MSI) is associated with improved survival rates. We investigated the relationship between tumor expression of angiogenic growth factors and genomic alterations in colorectal cancer. METHODS: Two genotypes, LOH and MSI, determined by microsatellite markers in the 4 cancer-related chromosomes 2p, 3p, 17p, and 18q, were analyzed in 73 patients with colorectal cancer. The tumor-specific expression of vascular endothelial growth factor and hepatocyte growth factor (HGF) were quantified, and the interleukin-6 network also was evaluated. RESULTS: MSI-positive neoplasms showed a lesser expression of both tumor growth factors and interleukin-6. In contrast, LOH-positive neoplasms showed a greater expression of HGF and a lesser expression of interleukin-1-receptor antagonist. MSI neoplasms were correlated with favorable prognosis in agreement with previous findings. CONCLUSIONS: The suppressed production of angiogenic growth factors in MSI cancers partly might explain the better prognosis in MSI-positive patients. The interleukin-6 network, which upregulates production of vascular endothelial growth factor and HGF, might be involved in this mechanism. 相似文献
40.
Tsutomu Takeuchi Jun Koide Osamu Hosono Koichi Amano Mitsuo Homma Yasuhiko Masuho Chikao Morimoto Makoto Takano Tohru Abe 《Arthritis \u0026amp; Rheumatology》1986,29(10):1216-1222
Elevated production of anti-DNA antibody in patients with systemic lupus erythematosus (SLE) is a central problem in the pathogenesis of tissue injury. In the present study, we attempted to manipulate anti-DNA antibody production through the antigen-cytotoxic drug conjugates, DNA-daunorubicin complexes. The effect of DNA-daunorubicin complexes was determined by examining SLE lymphocytes for spontaneous in vitro production of anti-DNA antibody. These complexes, at 2 μg/ml, suppressed anti-DNA antibody production, but not total IgG production, which suggests that specific suppression of anti-DNA antibody production was achieved at this concentration. We believe that the DNA-daunorubicin complexes affected mainly B cells, since such suppression was obtained by treating B cells, as well as B plus T cells. Furthermore, the complexes had no effect on the proliferative responses of SLE T cells to DNA, phytohemagglutinin, or concanavalin A. These results indicate that DNA-daunorubicin complexes may have the potential for selectively suppressing anti-DNA antibody production in patients with SLE. 相似文献