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991.
Bruehl S al'Absi M France CR France J Harju A Burns JW Chung OY 《Journal of behavioral medicine》2007,30(3):209-219
This study explored possible gender moderation of previously reported associations between elevated trait anger-out and reduced
endogenous opioid analgesia. One hundred forty-five healthy participants underwent acute electrocutaneous pain stimulation
after placebo and oral opioid blockade in separate sessions. Blockade effects were derived reflecting changes in pain responses
induced by opioid blockade. Hierarchical regressions revealed that elevated anger-out was associated with smaller pain threshold
blockade effects (less opioid analgesia) in females, with opposite findings in males (interaction p < .001). Similar marginally significant interactions were noted for blockade effects derived for nociceptive flexion reflex
threshold, pain tolerance, and pain ratings (p < .10). Anger-in was also associated negatively with pain threshold blockade effects in females but not males (interaction
p < .05). Across genders, elevated anger-in was related to smaller pain tolerance blockade effects (p < .01). Overlap with negative affect did not account for these opioid effects. The anger-in/opioid association was partially
due to overlap with anger-out, but the converse was not true. These findings provide additional evidence of an association
between trait anger-out and endogenous opioid analgesia, but further suggest that gender may moderate these effects. In contrast
to past work, anger-in was related to reduced opioid analgesia, although overlap with anger-out may contribute to this finding. 相似文献
992.
CD8+ T cells promote inflammation and apoptosis in the liver after sepsis: role of Fas-FasL
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Wesche-Soldato DE Chung CS Gregory SH Salazar-Mather TP Ayala CA Ayala A 《The American journal of pathology》2007,171(1):87-96
Although studies blocking the Fas pathway indicate it can decrease organ damage while improving septic (cecal ligation and puncture, CLP) mouse survival, little is known about how Fas-Fas ligand (FasL) interactions mediate this protection at the tissue level. Here, we report that although Fas expression on splenocytes and hepatocytes is up-regulated by CLP and is inhibited by in vivo short interfering RNA, FasL as well as the frequency of CD8(+) T cells are differentially altered by sepsis in the spleen (no change in FasL, decreased percentage of CD8(+) and CD4(+) T cells) versus the liver (increased FasL expression on CD8(+) T cells and increase in percentage/number). Adoptive transfer of CLP FasL(+/+) versus FasL(-/-) mouse liver CD8(+) T cells to severe combined immunodeficient or RAG1(-/-) recipient mice indicated that these cells could induce inflammation. The FasL-mediated cytotoxic capacity of these septic mouse liver CD8(+) T cells was shown by their ability to damage directly cultured hepatocytes. Finally, although CD8(-/-) mice exhibited a reduction in both CLP-induced liver active caspase-3 staining and blood interleukin-6 levels, only FasL(-/-) (but not CD8(-/-)) protected the septic mouse spleen from increasing apoptosis. Thus, although truncating Fas-FasL signaling ameliorates many untoward effects of sepsis, the pathological mode of action is distinct at the tissue level. 相似文献
993.
Chung GG Zerkowski MP Ghosh S Camp RL Rimm DL 《Laboratory investigation; a journal of technical methods and pathology》2007,87(7):662-669
Immunohistochemical analyses (IHC) of biomarkers are extensively used for tumor characterization and as prognostic and predictive measures. The current standard of single slide analysis assumes that one 5 microM section is representative of the entire tumor. We used our automated image analysis technology (AQUA) using a modified IHC technique with fluorophores to compare estrogen receptor (ER) expression in multiple blocks/slides from cases of primary breast cancer with the objective of quantifying tumor heterogeneity within sections and between blocks. To normalize our ER scores and allow slide-to-slide comparisons, 0.6 microm histospots of representative breast cancer cases with known ER scores were assembled into a 'gold standard array' (GSA) and placed adjacently to each whole section. Overall, there was excellent correlation between AQUA scores and the pathologist's scores and reproducibility of GSA scores (mean linear regression R value 0.8903). Twenty-nine slides from 11 surgical cases were then analyzed totaling over 2000 AQUA images. Using standard binary assignments of AQUA (>10) and pathologist's (>10%) scores as being positive, there was fair concordancy between AQUA and pathologist scores (73%) and between slides from different blocks from the same cases (75%). However using continuous AQUA scores, agreement between AQUA and pathologist was far lower and between slides from different blocks from the same cases only 19%. Within individual slides there was also significant heterogeneity in a scattered pattern, most notably for slides with the highest AQUA scores. In sum, using a quantitative measure of ER expression, significant block-to-block heterogeneity was found in 81% of cases. These results most likely reflect both laboratory-based variability due to lack of standardization of immunohistochemistry and true biological heterogeneity. It is also likely to be dependent on the biomarker analyzed and suggests further studies should be carried out to determine how these findings may affect clinical decision-making processes. 相似文献
994.
alpha-CaMKII controls the growth of human osteosarcoma by regulating cell cycle progression 总被引:1,自引:0,他引:1
Yuan K Chung LW Siegal GP Zayzafoon M 《Laboratory investigation; a journal of technical methods and pathology》2007,87(9):938-950
Osteosarcoma is the most frequent type of primary bone cancer in children and adolescents. These malignant osteoid forming tumors are characterized by their uncontrolled hyperproliferation. Here, we investigate the role of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) in the growth of human osteosarcoma. We show that alpha-CaMKII is expressed in human osteosarcoma cell lines and in primary osteosarcoma tissue derived from patients. The pharmacologic inhibition of CaMKII in MG-63 and 143B human osteosarcoma cells by KN-93 resulted in an 80 and 70% decrease in proliferation, respectively, and induced cell cycle arrest in the G(0)/G(1) phase. The in vivo administration of KN-93 to mice xenografted with human osteosarcoma cells significantly decreased intratibial and subcutaneous tumor growth. Mechanistically, KN-93 and alpha-CaMKII siRNA increased p21((CIP/KIP)) gene expression, protein levels, and decreased the phosphorylation of retinoblastoma protein and E2F transactivation. Furthermore, the inhibition of CaMKII decreased membrane-bound Tiam1 and GTP-bound Rac1, which are known to be involved in p21 expression and tumor growth in a variety of solid malignant neoplasms. Our results suggest that CaMKII plays a critical role in the growth of osteosarcoma, and its inhibition could be an attractive therapeutic target to combat conventional high-grade osteosarcoma in children. 相似文献
995.
996.
Administration of peptide antigens in tolerogenic form holds promise as a specific treatment for autoimmune and allergic disorders. However, experiments in rodent autoimmune models have highlighted the risk of anaphylaxis in response to systemic peptide application once the aberrant immune response is underway. Thus, mice with clinical signs of experimental autoimmune encephalomyelitis (EAE) or diabetes have been reported to suffer fatal anaphylaxis upon administration of native autoantigenic peptides. Clearly, this might represent a significant barrier to the use of synthetic peptides in the treatment of ongoing human autoimmune conditions. Here we describe the development of an altered peptide ligand (APL) engineered to prevent anaphylaxis (no antibody binding) whilst retaining the ability to silence pathogenic myelin-reactive T lymphocytes. Administration of the APL to mice with an ongoing anti-myelin immune response did not cause anaphylaxis, but led to complete protection from the subsequent induction of EAE and, when given during ongoing EAE, led to a rapid remission of clinical signs. The approach of removing antibody recognition whilst maintaining the desired functional effect (in this case T cell tolerance) may be of value in other situations in which there is a risk of triggering anaphylaxis with peptide-based drugs. 相似文献
997.
Kinematic approaches using MR images have been regarded of more accuracy in knee pain (AKP) detection than stationary approaches. However, the challenge in segmenting femur, patellar and tibia due to the intensity non-uniformity caused by magnetic propagation degradation in MR images, and the strong adhesion of the soft tissue around the knee organs, has restricted the use of kinematic approaches. This paper proposes a combinatorial based kinematic patellar tracking (CKPT) for AKP detection. The CKPT uses a hybrid approach for extracting knee organs, where an edge-constrained wavelet enhancement followed by moment preserving segmentation is employed for conquering the soft tissue adhesion for extracting the femur and tibia from axial MR images, and a sliding window based moment preserving for resolving the segmentation difficulty associated with intensity non-uniformity in sagittal MR images. The location constraints are then applied for extracting landmark points from femur and patellar, and three inclination angles reflecting patellar position and orientation, during leg movement, are calculated as the measurement of patellar dislocation. The experiment shows that the hybrid approach can accurately extract femur, patellar and tibia. It also demonstrates the prominent of the calculated inclination angles in detecting AKP. 相似文献
998.
Yunseok Oh Yoo-Seong Jeong Min-Soo Kim Jee Sun Min Gongmi Ryoo Ji Eun Park Yearin Jun Yoo-Kyung Song Se-Eun Chun Songhee Han Soo Kyung Bae Suk-Jae Chung Wooin Lee 《Journal of pharmaceutical sciences》2018,107(6):1713-1723
Betulinic acid (BA), a plant-derived pentacyclic triterpenoid, may interact with the members of the organic anion transporting polypeptide 1B subfamily. Here, we investigated the interactions of BA and its analogs with OATP1B1/3 and rat Oatp1b2 in vitro and in vivo. BA inhibited the activity of OATP1B1/3 and rat Oatp1b2 in vitro. Systemic exposure of atorvastatin was substantially altered with the intravenous co-administration of BA (20 mg/kg). Preincubation (incubation with inhibitors, followed by washout) with BA led to a sustained inhibition of OATP1B3, which recovered rapidly in the media containing 10% fetal bovine serum. The addition of albumin to the media decreased intracellular concentrations of BA and expedited the recovery of OATP1B3 activity following preincubation. For asunaprevir and cyclosporin A (previously known to inhibit OATP1B3 upon preincubation), the addition of albumin to the media shortened recovery time with asunaprevir, but not with cyclosporin A. Overall, our results showed that BA inhibits OATP1B transporters in vitro and may incur hepatic transporter-mediated drug interactions in vivo. Our results identify BA as another OATP1B3 inhibitor with preincubation effect and suggest that the preincubation effect and its duration is impacted by altered equilibrium of inhibitors between intracellular and extracellular space (e.g., albumin in the media). 相似文献
999.
Jae Hoon Chung Cheol Young Oh Jae Heon Kim U-Syn Ha Tae Hyo Kim Seung Hwan Lee 《Current medical research and opinion》2018,34(10):1793-1801
Objective: To verify the efficacy and safety of tamsulosin 0.4?mg and tamsulosin 0.2?mg compared with those of placebo in patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).Methods: A total of 494 patients from multiple centers participated in this double-blind, randomized, phase 3 trial. Eligible patients were randomly assigned to the tamsulosin 0.4?mg group, tamsulosin 0.2?mg group or placebo group. The International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), post-void residual (PVR) urine volume, blood pressure, heart rate and adverse events were compared among the three groups at 4, 8 and 12 weeks.Results: A total of 494 BPH patients were analyzed. There were no differences in the baseline characteristics among the three groups. After 12 weeks of treatment, total IPSS was improved in the 0.2?mg and 0.4?mg tamsulosin groups; however, the extent of improvement was greater in the 0.4?mg group than in the 0.2?mg group (0.4?mg: ?9.59 vs. 0.2?mg: ?5.61; least-squares mean difference [95% confidence interval]: ?3.95 [?5.01, ?2.89], p?.0001). In addition, in the patients with severe symptoms (IPSS ≥20), total IPSS was improved the most in the 0.4?mg group (?11.27?±?5.00, p?.0001). Qmax and PVR were improved in the 0.4?mg and 0.2?mg groups; however, the differences were not statistically significant between treatment groups. No patients experienced any serious adverse effects in any of the three groups.Conclusions: Tamsulosin 0.4?mg and 0.2?mg appear to be superior to placebo treatment, and tamsulosin 0.4?mg is more effective than 0.2?mg in terms of total IPSS improvement. Tamsulosin 0.4?mg has favorable efficacy and tolerability in Asian men with symptomatic BPH.ClinicalTrials.gov Identifier: NCT02390882. 相似文献
1000.
Proton pump inhibitors are associated with accelerated development of cirrhosis,hepatic decompensation and hepatocellular carcinoma in noncirrhotic patients with chronic hepatitis C infection: results from ERCHIVES
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D. K. Li P. Yan A‐B. Abou‐Samra R. T. Chung A. A. Butt 《Alimentary pharmacology & therapeutics》2018,47(2):246-258