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61.
62.
Objective. The purpose of this study was to differentiate between high‐grade and non–high‐grade ductal carcinoma in situ (DCIS) of the breast on sonography. Methods. From October 2003 to August 2009, 76 DCIS lesions in 73 women who underwent sonography and mammography were included in this study. Lesions were confirmed by mastectomy, breast‐conserving surgery, or surgical biopsy. Images were analyzed by 2 radiologists with consensus and were correlated with histologic grades. Results. Of the 76 lesions, 44 were classified as high‐‐grade and 32 as non–high‐grade DCIS. Fifty‐seven lesions (75.0%) were identified on sonography, which revealed a mass in 30 cases, microcalcifications in 20, ductal changes in 4, and architectural distortion in 3. All cases with false‐negative findings on sonography (n = 19) showed microcalcifications on mammography. On sonography, masses were more frequently found in non–high‐grade (62.5%) than high‐grade DCIS (22.7%; P < .01). No significant difference was seen in the sonographic features of masses between high‐grade and non–high‐grade DCIS. Microcalcifications were more common in high‐grade (43.2%) than non–high‐grade (3.1%) DCIS (P = .02). Most sonographically visible microcalcifications had associated findings such as ductal changes (n = 11), a mass (n = 7), or a hypoechoic area (n = 5). The detection rate of microcalcifications on sonography was higher in high‐grade (62.9%) than non–high‐grade DCIS (25.0%; P = .023). Conclusions. Microcalcifications with associated ductal changes (11 of 31 [35.5%]) were the most common sonographic findings in high‐grade DCIS. An irregular hypoechoic mass with an indistinct and microlobulated margin (13 of 26 [50.0%]) was the most frequent finding in non–high‐grade DCIS.  相似文献   
63.
Expression of protease-activated receptor 2 in ulcerative colitis   总被引:4,自引:0,他引:4  
Although tryptase released from mast cells might play a key role in the pathogenesis of ulcerative colitis (UC), the role of protease-activated receptor 2 (PAR2), tryptase receptor, remains unclear in the pathogenesis of this disease. The expressions of PAR2 and tumor necrosis factor (TNF) alpha in nine UC tissues and nine normal tissues were examined by immunohistochemistry. TNF-alpha levels secreted from human leukemic mast cell line (HMC-1) after the treatment of PAR2 agonists were also measured by enzyme-linked immunosorbent assay. The PAR2 and TNF-alpha proteins were more significantly detectable in UC tissues than in normal tissues. Furthermore, 65.2% of PAR2+ cells and 66.4% of TNF-alpha+ cells in UC tissues were tryptase-positive cells. In other words, 60.6% and 46.3% of tryptase-positive cells in UC tissues were PAR2+ cells and TNF-alpha+ cells, respectively. A chi2 analysis showed correlation (p < 0.007) between PAR2 and TNF-alpha in tryptase-positive mast cells. Moreover, PAR2 agonists significantly induced the TNF-alpha secretion from HMC-1. These results indicate that the activation of the mast cells through PAR2 may be involved in the pathogenesis of UC.  相似文献   
64.
Thioredoxin 2 (Trx2) is a mitochondrially localized antioxidant and antiapoptotic protein, whose functions are mainly dependent on the conserved cysteines at its redox active center. In the current study, we showed by mass spectrometry that a thiol alkylating agent, N-ethylmaleimide (NEM), alkylated a single cysteine residue in the active center of Trx2. The interaction between NEM and Trx2 in intact cells was confirmed by redox Western analysis. Overexpression of Trx2 in cultured 143B osteosarcoma cells caused increased sensitivity to NEM. Covalent modification by NEM resulted in a dominant-negative effect and increased the interaction between Trx2 and peroxiredoxin 3 (Prx3). Our data suggest that the alkylation of the essential thiol(s) of Trx2 has profound impact on the mitochondrial redox circuitry and that such effects are distinct from the responses to agents causing reversible disulfide bond formation between the vicinal dithiols in the active center.  相似文献   
65.
Anopheles sinensis Wiedemann (63.3%) was the most abundant Anopheles mosquito captured at cowshed resting collections in malaria high-risk areas (northern Gyeonggi Province) near the demilitarized zone (DMZ) in Korea during 2005, followed by Anopheles kleini Rueda (24.7%) and Anopheles pullus M. Yamada (8.7%). At cowshed resting collections in malaria low-risk areas (Jeonnam and Gyeongnam provinces), An. sinensis accounted for 96.8% of all Anopheles spp. collected, followed by An. kleini Rueda (2.7%), whereas no An. pullus were collected. Three species, An. kleini (50.9%), An. pullus (29.0%), and An. sinensis (13.8%), accounted for nearly all of the 224 Anopheles spp. captured by New Jersey light trap near the DMZ. In addition, An. pullus and An. kleini captured by New Jersey light trap near the DMZ and assayed by enzyme linked immunosorbent assay for Plasmodium vivax circumsporozoite antigen concentrations were higher than An. sinensis sensu stricto (s.s.), indicating higher levels of sporozoites. In laboratory studies of four concurrent artificial membrane feedings on malaria-infected blood from patients, F1 progeny of An. kleini and An. pullus had higher infection rates (8.8 and 7.5%, respectively) than An. sinensis s.s. (4.2%). These data suggest that An. kleini and An. pullus and An. sinensis are vectors of malaria in Korea. Further studies are required to determine the role of these species in the transmission of P. vivax in the Republic of Korea.  相似文献   
66.
Background: Lonicera japonica (Caprifoliaceae) has long been used for treatment of infectious diseases. In the present study, the anti-inflammatory effects of L. japonica water extract (AELJ) were investigated in proteinase-activated receptor 2 (PAR2)-mediated mouse paw edema. Methods: Paw edema was induced by injection of trypsin or trans-cinnamoyl-LIGRLO-NH2 (tc-NH2) into hindpaw of mice. AELJ (10, 50, 100, and 200 mg/kg) was orally administered 1 h before induction of inflammation. Results: At doses of 50, 100 and 200 mg/kg, the AELJ showed significant inhibition of both change in paw thickness and vascular permeability. The AELJ (100 mg/kg) also significantly inhibited PAR2 agonists-induced myeloperoxidase (MPO) activity and tumor necrosis factor (TNF)- expression in paw tissue. Conclusion: The present study demonstrated that AELJ has an anti-inflammatory action for PAR2-mediated paw edema.  相似文献   
67.
BACKGROUND: Solanum melongena L. (Solanaceae) has antioxidant, analgesic, hypolipidemic and antiallergic activity. METHODS: The anti-inflammatory effects of the water extract of the S. melongena (SMWE) were investigated in PAR2-mediated mouse paw edema. Paw edema was induced by injection of trypsin or trans-cinnamoyl-LIGRLO-NH(2) (tc-NH(2)) into the hindpaw of mice. The SMWE (1, 5, 10, and 100 mg/kg) was orally administered 1 h before induction of inflammation. RESULTS: At doses of 5, 10, and 100 mg/kg, the SMWE showed significant inhibition of both paw edema and vascular permeability. The SMWE (10 mg/kg) significantly also inhibited PAR2 agonist-induced myeloperoxidase (MPO) activity and tumor necrosis factor (TNF)-alpha expression in paw tissue. CONCLUSION: These results demonstrate that the SMWE inhibits PAR2 agonist-induced mouse paw edema.  相似文献   
68.
The combined extracts obtained from three Chinese herb medicine, Kalopanax pictus, Pueraria thunbergiana and Rhus verniciflua, have been used as therapeutics for diabetes mellitus in Korea. In the present study, we have investigated their possible anti-inflammatory effects by comparing the potency of individual extracts with that of the combined extracts. An individual water extract prepared from Kalopanax pictus, Pueraria thunbergiana, and Rhus verniciflua was named K-1, P-1, and R-1, respectively. Simultaneously, we also prepared the combined extracts from above three plant materials by identical methods and named KPR-1. These four extracts were further fractionated into the EtOAc extracts, and these were designated as K-2, P-2, R-2, and KPR-2, respectively. These eight samples were subjected to the nitrite assays in LPS-induced macrophage 264.7 cells. KPR-2 exhibited the most pronounced effect on the inhibition of NO production among all the extracts. KPR-2 also significantly decreased PGE2, and TNF-alpha release. In addition, KPR-2 showed in vivo anti-inflammatory activity against acute paw edema induced by carrageenan in rats. When analgesic activity was measured by the acetic acid-induced abdominal constriction and hot plate test, KPR-2 showed a dose-dependent inhibition in animal models. These results suggested that the mixture extract and successive fractionation could lead to the better use of anti-inflammatory medicinal crude drugs.  相似文献   
69.
In contrast to mammals, adult zebrafish have the ability to regrow descending axons and gain locomotor recovery after spinal cord injury (SCI). In zebrafish, a decisive factor for successful spinal cord regeneration is the inherent ability of some neurons to regrow their axons via (re)expressing growth-associated genes during the regeneration period. The nucleus of the medial longitudinal fascicle (NMLF) is one of the nuclei capable of regenerative response after SCI. Using microarray analysis with laser capture microdissected NMLF, we show that cysteine- and glycine-rich protein (CRP)1a (encoded by the csrp1a gene in zebrafish), the function of which is largely unknown in the nervous system, was upregulated after SCI. In situ hybridization confirmed the upregulation of csrp1a expression in neurons during the axon growth phase after SCI, not only in the NMLF, but also in other nuclei capable of regeneration, such as the intermediate reticular formation and superior reticular formation. The upregulation of csrp1a expression in regenerating nuclei started at 3 days after SCI and continued to 21 days post-injury, the longest time point studied. In vivo knockdown of CRP1a expression using two different antisense morpholino oligonucleotides impaired axon regeneration and locomotor recovery when compared with a control morpholino, demonstrating that CRP1a upregulation is an important part of the innate regeneration capability in injured neurons of adult zebrafish. This study is the first to demonstrate the requirement of CRP1a for zebrafish spinal cord regeneration.  相似文献   
70.
Previous reports have suggested that a high serum cyclosporine A (CsA) level could result in a lower incidence of acute-graft-versus-host disease (aGVHD). An elevated serum lactate dehydrogenase (LDH) level has been reported to be an adverse predictor of outcome in stem cell transplantation (SCT) for acute myeloid leukemia. In this study, we retrospectively analyzed the records of 24 patients who received allogeneic SCT from an HLA-matched sibling donor for acute and chronic myelogenous leukemia. Univariate analysis showed that two factors (the serum CsA level at the third week after SCT and the LDH level at the third week after SCT) were significantly associated with the incidence of aGVHD among several variables (age, sex, stem cell source, cell dose, C-reactive protein, absolute lymphocyte count, conditioning regimens, and time to engraftment). A higher serum level of CsA and lower serum LDH level at the third week after SCT were associated with a lower incidence of aGVHD (P=0.015, 0.030). In multivariate analysis, the serum CsA level (hazard ratio [HR], 0.12; 95% confidence interval [CI], 0.022-0.652, P=0.0014) and serum LDH level (HR, 6.59; 95% CI, 1.197-36.316, P=0.030) at the third week after SCT were found to be independent factors that were significantly associated with the development of aGVHD. We conclude that a high CsA level and low LDH level might predict a low cumulative incidence of aGVHD after allogeneic transplantation from a matched sibling donor.  相似文献   
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