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991.
Takeuchi M Keino H Suzuki J Usui Y Hattori T Takeuchi A Oh-I K Okunuki Y Kezuka T Usui M 《Experimental eye research》2006,83(4):981-988
Murine macrophages treated with TGF-beta2 are capable of inducing anterior chamber-associated immune deviation (ACAID), and these macrophages are characterized by impaired IL-12 production and CD40 expression, consequently failing to promote Th1 cell differentiation. In this study, we investigated whether human monocytes can also acquire the specific functions by TGF-beta2 treatment, even when the monocytes are isolated from patients with Behcet's disease (BD). Adherent monocytes isolated from peripheral blood mononuclear cells (PBMC) of 16 BD patients and 16 healthy controls, were cultured overnight with or without 5 ng/ml of TGF-beta2. Then, TGF-beta2-treated or untreated adherent cells were co-cultured with allogeneic CD4(+) T cells obtained from healthy subjects. TGF-beta2 treatment inhibited the abilities of adherent monocytes obtained from BD patients to stimulate the proliferation and IFN-gamma production of allogeneic CD4(+) T cells. The reduced IFN-gamma production was also confirmed by IFN-gamma mRNA expression in the co-cultured T cells. IL-12 production and CD40 molecule expression by adherent monocytes obtained from BD patients were strikingly reduced by TGF-beta2 treatment. These results suggest a possibility that adherent monocytes isolated from BD patients may acquire a property to induce ACAID by treatment with TGF-beta2. 相似文献
992.
Classification of Ophthalmic Artery Flow in Patients with Occlusive Carotid Artery Disease 总被引:2,自引:0,他引:2
Fujioka S Karashima K Nakagawa H Saito Y Nishikawa N 《Japanese journal of ophthalmology》2006,50(3):224-228
Purpose
To investigate and classify the ophthalmic artery (OA) flow patterns in patients with occlusive carotid artery disease (OCAD).Methods
Forty-three patients (52 eyes) with documented OCAD of ≧70% underwent orbital color Doppler imaging. The eyes were first divided into four groups by peak systolic velocity in OA (PSVOA): group A, PSVOA ≦ 0; group B, 0 < PSVOA ≦ 10; group C, 10 < PSVOA ≦ 40; and group D, PSVOA > 40?cm/s, then further classified by the shape of the OA flow wave. The groups were then compared with respect to the collateral pathway (Co-Path), severity of the OCAD, and systemic diseases.Results
Eyes with unidirectional reverse flow (group A1) had a Co-Path from the ipsilateral external carotid artery and 70%–100% OCAD. Eyes with bidirectional reverse flow (group A2) had no Co-Path, 75% OCAD, and impending ischemic heart disease (IHD). Group B eyes had dome-shaped OA flow waves with no Co-Path and 99%–88% OCAD. Group C1 eyes, with normal flow waves, had a Co-Path from the contralateral internal carotid artery and 100% OCAD. Group C2 eyes, with triangular-shaped flow waves, had no Co-Path, 93%–70% OCAD, and IHD. Group D eyes had normal high flow waves with no Co-Path, 75% OCAD, and hypertension.Conclusions
The OA flow patterns were variously affected by collateral pathway, severity of OCAD, and systemic diseases.?Jpn J Ophthalmol 2006;50:224–228 © Japanese Ophthalmological Society 2006 相似文献993.
Murayama K Takita H Kiyohara Y Shimizu Y Tsuchida T Yoneya S 《Nippon Ganka Gakkai zasshi》2006,110(3):211-217
BACKGROUND: We report the clinical features of the first case of a Japanese person with melanoma-associated retinopathy. CASE: A 44-year-old woman complained of photopsia and blurred vision in her right eye, and was treated with steroids for uveitis by an ophthalmologist. She was referred to our hospital for further examination. After one month of treatment, she still complained of photopsia in her right eye. The best corrected visual acuity in the right eye was 0.8 and these was sensitivity loss in the central visual field test. Ophthalmoscopy and fluorescein angiography showed some retinal vasculitis in the right eye. A full-field electroretinogram demonstrated a negative-type electroretinogram (ERG) waveform with attenuation of the b-wave amplitude in the right eye. A dark adaptation test revealed sensitivity loss of the rods. The lymph nodes on the right side of her neck were examined and the diagnosis was made of metastic cutaneous melanoma with unknown primary site; her visual dysfunction was diagnosed as melanoma-associated retinopathy. The retinal inflammation improved after steroid treatment, but her visual dysfunction remained. Chemotherapy and an immunotherapy regimen was begun, but 36 months later she died of metastatic melanoma in the lungs. CONCLUSIONS: A woman treated for uveitis without any prior systemic and ocular diseases was diagnosed with melanoma-associated retinopathy and metastatic melanoma in the cervical lymph nodes of unknown primary origin. The first ocular symptoms were photopsia and blurred vision, not night blindness. ERG was useful for diagnosing this rare ocular condition in an early stage. 相似文献
994.
Five 3-alkylpyridine alkaloids, amphimedosides A-E (1-5), have been isolated from a marine sponge Amphimedon sp. The structures of 1-5 have been determined by analysis of NMR and FABMS data and chiral GC analyses of the acid hyrolyzates. In particular, the site of glycosylation in 1 was confirmed by the 1H-15N HMBC experiment, and the location of the double bond in 5 was assigned on the basis of tandem FABMS data. Amphimedosides are the first examples of beta-D-glucosylated 3-alkylpyridine alkaloids and exhibited cytotoxic activities comparable with those of the nonglycosylated congeners. 相似文献
995.
Nakajima M Itoh M Sakai H Fukami T Katoh M Yamazaki H Kadlubar FF Imaoka S Funae Y Yokoi T 《International journal of cancer. Journal international du cancer》2006,119(11):2520-2526
Cigarette smoking is the predominant risk factor for bladder cancer. Aromatic amines such as 4-aminobiphenyl (ABP) is the major carcinogens found in tobacco smoke. Although it is generally accepted that ABP is metabolically activated via N-hydroxylation by CYP1A2 in human liver, previous studies using Cyp1a2-null mice indicated the involvement of other enzyme(s). Here we found that CYP2A13 can metabolically activate ABP to show genotoxicity by Umu assay. The K(m) and V(max) values for ABP N-hydroxylation by recombinant CYP2A13 in E. coli were 38.5 +/- 0.6 microM and 7.8 +/- 0.0 pmol/min/pmol CYP, respectively. The K(m) and V(max) values by recombinant CYP1A2 were 9.9 +/- 0.9 microM and 39.6 +/- 0.9 pmol/min/pmol CYP, respectively, showing 20-fold higher intrinsic clearance than CYP2A13. In human bladder, CYP2A13 mRNA, but not CYP1A2, is expressed at a relatively high level. Human bladder microsomes showed ABP N-hydroxylase activity (K(m) = 34.9 +/- 4.7 microM and V(max) = 57.5 +/- 1.9 pmol/min/mg protein), although the intrinsic clearance was 5-fold lower than that in human liver microsomes (K(m) = 33.2 +/- 2.0 microM and V(max) = 293.9 +/- 5.8 pmol/min/mg protein). The activity in human bladder microsomes was prominently inhibited by 8-methoxypsoralen, but not by fluvoxamine, anti-CYP1A2 or anti-CYP2A6 antibodies. CYP2S1, which is expressed in human bladder and has relatively high amino acid identities with CYP2As, did not show detectable ABP N-hydroxylase activity. In conclusion, although the enzyme responsible for ABP N-hydroxylation in human bladder microsomes could not be determined, we found that CYP2A13 metabolically activates ABP. 相似文献
996.
Ide T Kitajima Y Miyoshi A Ohtsuka T Mitsuno M Ohtaka K Koga Y Miyazaki K 《International journal of cancer. Journal international du cancer》2006,119(12):2750-2759
The hypoxic environment in tumor is reported to play an important role in pancreatic cancer progression. The interaction between stromal and cancer cells also contributes to the malignant behavior of pancreatic cancer. In the present study, we investigated whether hypoxic stimulation affects stromal as well as pancreatic cancer cells. Our findings demonstrated that hypoxia remarkably elevated the HIF-1alpha expression in both pancreatic cancer (PK8) and fibroblast cells (MRC5). Hypoxic stimulation accelerated the invasive activity of PK8 cells, and invasiveness was thus further accelerated when the hypoxic PK8 cells were cultured with conditioned medium prepared from hypoxic MRC5 cells (hypoxic conditioned medium). MMP-2, MMP-7, MT1-MMP and c-Met expressions were increased in PK8 cells under hypoxia. Hypoxic stimulation also increased the hepatocyte growth factor (HGF) secretion from MRC5 cells, which led to an elevation of c-Met phosphorylation in PK8 cells. Conversely, the elevated cancer invasion, MMP activity and c-Met phosphorylation of PK8 cells were reduced by the removal of HGF from hypoxic conditioned medium. In immunohistochemical study, the HIF-1alpha expression was observed in surrounding stromal as well as pancreatic cancer cells, thus indicating hypoxia exists in both of cancer and stromal cells. Moreover, the stromal HGF expression was found to significantly correlate with not only the stromal HIF-1alpha expression but also the c-Met expression in cancer cells. These results indicate that the hypoxic environment within stromal as well as cancer cells activates the HGF/c-Met system, thereby contributing to the aggressive invasive features of pancreatic cancer. 相似文献
997.
Clinicopathologic significance of hypoxia-inducible factor 1alpha overexpression in gastric carcinomas 总被引:4,自引:0,他引:4
Mizokami K Kakeji Y Oda S Irie K Yonemura T Konishi F Maehara Y 《Journal of surgical oncology》2006,94(2):149-154
BACKGROUND: Hypoxia-inducible factor 1alpha (HIF-1alpha) plays a key role in responses to hypoxia and expression of HIF-1alpha downstream genes leads to both an adapted metabolism and increased oxygen supply. We investigated the clinical significance of HIF-1alpha expression in gastric carcinoma. METHODS: We examined HIF-1alpha, vascular endothelial growth factor (VEGF), and insulin-like growth factor-2 (IGF-2) expression patterns immunohistochemically in 126 specimens of gastric carcinoma. CD34 antigen levels were also examined by immunohistochemistry to determine microvessel density (MVD) within tumors and correlations between HIF-1alpha expression, clinicopathological features, and survival were examined. RESULTS: HIF-1alpha expression correlated with tumor size (P<0.005), depth of invasion (P=0.018), VEGF expression (P=0.03), and intra-tumor MVD (P<0.005). IGF-2 expression was more prevalent in HIF-1alpha positive than in HIF-1alpha negative tumors and the 5-year survival rate was 58.4% for HIF-1alpha positive patients and 81.5% for HIF-1alpha negative patients (P=0.009). HIF-1alpha expression is an independent prognostic factor in gastric carcinoma (P=0.032). CONCLUSIONS: Overexpression of HIF-1alpha in gastric carcinomas may upregulate its downstream gene products leading to VEGF-mediated angiogenesis, and resulting in a poor prognosis for patients. 相似文献
998.
999.
Osoegawa A Yoshino I Kometani T Yamaguchi M Kameyama T Yohena T Maehara Y 《Cancer》2006,107(1):154-161
BACKGROUND: Decreased expression of p27, which is an inhibitor of cyclin-dependent kinase, is associated with cancer aggressiveness. It is believed that Jun activation domain-binding protein 1 (Jab1) plays a role in p27 degradation in a manner that is independent from the role played by S-phase kinase-associated protein 2 (Skp2). To examine the clinical significance of Jab1 in nonsmall cell lung cancer (NSCLC), the protein expression of Jab1 in tumor tissues was investigated with regard to the expression of p27 and Skp2. METHODS: The clinicopathologic features and immunohistochemical expression levels of Jab1, p27, and Skp2 proteins were studied in 138 specimens from patients who underwent surgical resection for NSCLC. Survival analyses were performed by using the Kaplan-Meier method and Cox regression models. RESULTS: High Jab1 expression (>50% of cancer cell nuclei stained) was observed in 81 specimens (59%). In Skp2-negative specimens (n = 81), an inverse correlation between the protein expression of p27 and Jab1 was observed both with the chi-square test (P = .02) and with the Mann-Whitney U test (P = .02). High Jab1 expression levels were related to poor outcomes in 118 patients who underwent complete resection, with a 5-year overall survival rate of 43.9% for patients who had high Jab1 expression and 63.1% for patients who had low Jab1 expression (P = .01). This difference was greater in patients who had Skp2-negative specimens (51.9% vs. 79.3% (P = .02), but it was not significant in patients who had Skp2-positive specimens. The multivariate analysis revealed that Jab1 expression was an independent prognostic factor for survival in patients with NSCLC (relative risk, 2.247; P = .01). CONCLUSIONS: The current results showed for the first time that high Jab1 protein expression is related to poor outcome in patients with NSCLC and that this protein may be a target of therapy in NSCLC. 相似文献
1000.
Summary Autologous tumor-specific T lymphocyte (ATTL) lines were derived from the peripheral blood mononuclear cells (PBMC) of a healthy
volunteer with human leukocyte antigen (HLA) -A*0201. These lines were achieved using interleukins -1β, -2, -4, and -6 and
the p53-based peptide from the 264–272 sequence of the wild-type p53 protein with a strong affinity against HLA-A*0201.
;The frequencies of CD3+, CD4+, and CD8+ lymphocytes were 94–96%, 30–34%, and 69–74%, respectively. ATTLs killed most of the
T2 cells pulsed with p53-derived peptide, but not against the T2 cells non-pulsed or pulsed with an irrelevant peptide. ATTLs
also killed TKB-14 cells, which have been derived from human glioblastoma multiforme, and exhibited HLA-A*0201 molecule and
immunohistochemical accumulation of p53 protein. These cytotoxic activities were inhibited by anti-CD3, anti-CD8, and anti-class
I antibodies.
These findings suggested that these ATTL lines might include CTL populations, which could recognize p53-derived peptide on
HLA-A*0201 and the p53-based peptide may play as an antigen on HLA-A*0201. When tumor antigens would be more analyzed in the
future, ATTL could be induced without the primary-cultured cells from tumor tissue and could be applied for cancer therapy. 相似文献