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991.
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
992.
993.
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
994.
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
995.
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
996.
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
997.
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
998.
Zhiling Guo Yiu Chung Tse Ying Zhang Qiang Sun Haley A. Vecchiarelli Robert Aukema Matthew N. Hill Tak Pan Wong Patricia Boksa 《European neuropsychopharmacology》2018,28(12):1405-1417
There is strong evidence that immune activation from prenatal infection increases the risk for offspring to develop schizophrenia. The endocannabinoid (eCB) system has been implicated in the pathophysiology of schizophrenia while models of cortical dysfunction postulate an imbalance between neuronal excitation and inhibition in the disorder. The current study examined the impact of prenatal immune activation on eCB-mediated inhibitory mechanisms. We compared two forms of eCB-related plasticity of evoked inhibitory postsynaptic currents, namely depolarization-induced suppression of inhibition (DSI) and metabotropic glutamate receptor-induced long term depression (mGluR-iLTD), in both the dorsal and ventral hippocampus between adolescent offspring from rat dams that received either saline or bacterial lipopolysaccharide (LPS) during pregnancy. Compared to prenatal saline offspring, prenatal LPS offspring displayed prolonged DSI and stronger mGluR-iLTD in the dorsal and ventral hippocampus, respectively. The sensitivity of mGluR-iLTD to the CB1 receptor antagonist AM251 was also lower in the dorsal hippocampus of prenatal LPS compared to prenatal saline offspring. Testing whether changes in eCB receptor signaling or levels could contribute to these changes in inhibitory transmission, we found region specific increases in 2-arachidonoylglycerol-stimulated signaling and in basal and mGluR-induced levels of anandamide in prenatal LPS offspring when compared to prenatal saline offspring. Our findings indicate that prenatal immune activation can lead to long-term changes in eCB-related plasticity of hippocampal inhibitory synaptic transmission in adolescent rat offspring. Perturbation of the eCB system resulting from prenatal immune activation could represent a mechanism linking early life immune events to the development of psychopathology in adolescence. 相似文献
999.
Collaborate across silos: Perceived barriers to integration of care for the elderly from the perspectives of service providers
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1000.
A 45-year-old man with paranoid schizophrenia with delusions was transferred from a group home for treatment of diabetic ketoacidosis (DKA). Six months before this episode, he had been hospitalized in an inpatient psychiatric institution and treated with valproic acid and quetiapine 400 mg with normal blood sugars recorded. The patient was treated for diabetic ketoacidosis, and all outpatient medications were discontinued. Insulin resistance is commonly cited as the mechanism for hyperglycemia, a theory supported by the efficacy of insulin- sensitizing medications in reported cases. Although antipsychotic- associated DKA is uncommon, hyperglycemia associated with these medications is commonplace. Analysis of case series have not identified risk factors for hyperglycemia or diabetic ketoacidosis within this population. Considering the incidence and unpredictability of hyperglycemia associated with quetiapine and atypical antipsychotics, clinicians should initiate intensive monitoring in patients, including weight, hyperglycemia, and dyslipidemia. 相似文献