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941.
Hyunseong Kim Wanjin Jeon Jinyoung Hong Junseon Lee Changhwan Yeo Yoonjae Lee Seungho Baek Inhyuk Ha 《Nutrients》2021,13(12)
Gongjin-dan (GJD) is a multiherbal formula produced from 10 medicinal herbs and has been traditonally used as an oriental medicine to treat cardiovascular diseases, alcoholic hepatitis, mild dementia, and anemia. Additionally, increasing evidence suggests that GJD exerts neuroprotective effects by suppressing inflammation and oxidative stress-induced events to prevent neurological diseases. However, the mechanism by which GJD prevents oxidative stress-induced neuronal injury in a mature neuron remains unknown. Here, we examined the preventive effect and mechanism of GJD on primary cortical neurons exposed to hydrogen peroxide (H2O2). In the neuroprotection signaling pathway, Sirtuin1 is involved in neuroprotective action as a therapeutic target for neurological diseases. After pre-treatment with GJD at three concentrations (10, 25, and 50 µg/mL) and stimulation by H2O2 (30 µM) for 24 h, the influence of GJD on Sirtuin1 activation was assessed using immunocytochemistry, real-time PCR, western blotting, and flow cytometry. GJD effectively ameliorated H2O2-induced neuronal death against oxidative damage through Sirtuin1 activation. In addition, GJD-induced Sirtuin1 activation accelerated elongation of new axons and formation of synapses via increased expression of nerve growth factor and brain-derived neurotrophic factor, as well as regeneration-related genes. Thus, GJD shows potential for preventing neurological diseases via Sirtuin1 activation. 相似文献
942.
Stefania Pragliola Christopher K. Ober Patrick T. Mather Hong G. Jeon 《Macromolecular chemistry and physics.》1999,200(10):2338-2344
Stable free radical polymerization has been used in the controlled synthesis of poly(2,5-bis[(4-butylbenzoyl)oxy]styrene), PBBOS. This “mesogen-jacketed liquid crystalline polymer”, which has mesogenic units attached directly to the backbone in a side-on mode, has been found to exhibit thermotropic liquid crystallinity similar to more conventional main-chain architectures. Stable free radical polymerization of PBBOS consistently produced molecular weight distributions below the theoretical limiting polydispersity of 1.5 calculated for a conventional free radical polymerization process. Surprisingly, a comparison of the synthesis of polystyrene to the polymerization of PBBOS under nearly identical conditions showed that the PBBOS polymerized with a significantly higher reaction rate and monomer conversion efficiency. The nematic phase of these polymers was determined to be stable over the temperature range spanning the polymer glass transition temperature up to the temperature for thermal decomposition. The molecular arrangement of the PBBOS polymers was examined by wide-angle X-ray diffraction and is described here. 相似文献
943.
Young-Joon Kang Jong Min Baek Yong-Seok Kim Ye Won Jeon Tae-Kyung Yoo Jiyoung Rhu Chang-Hyun Shin Shijin Cho Hoon Choi Se Jeong Oh 《JOURNAL OF BREAST CANCER》2021,24(6):491
PurposeThe coronavirus disease 2019 (COVID-19) pandemic has significantly impacted the rates of screening, case identification, and referral for cancer diagnosis. We investigated the diagnosis and surgery status of breast cancer before and after the COVID-19 pandemic at a multi-institutional level.MethodsWe collected breast cancer data from the clinical data warehouse which contained the medical records of patients from six academic institutions in South Korea. Patients were divided into two groups: February to April (period A) and May to July (period B). The data from the two groups were then compared against the same periods in 2019 and 2020. The primary objective was to investigate the differences in breast cancer stages before and after the COVID-19 pandemic.ResultsAmong 3,038 patients, there was a 9.9% reduction in the number of diagnoses in 2020. This decrease was more significant during period A than period B. The breast cancer stage was not statistically different in period A (p = 0.115), but it was in period B (p = 0.001). In the subset analysis according to age, there was a statistical difference between 2019 and 2020 in period B for patients under the age of 65 years (p = 0.002), but no difference was observed in the other groups.ConclusionThe number of breast cancer cases declined during the pandemic, and the staging distribution has changed after the pandemic peak. 相似文献
944.
945.
Comparison of clipping with and without epinephrine injection for the prevention of post‐polypectomy bleeding in pedunculated colon polyps 下载免费PDF全文
946.
947.
Jae Yong Park Su Yeon Lee Hyo-Sung Jeon Nack Chun Bae Sang Chul Chae Soyoung Joo Chang Ho Kim Jae-Ho Park Sin Kam In San Kim Tae Hoon Jung 《Cancer epidemiology, biomarkers & prevention》2002,11(1):23-27
DNA repair plays a critical role in protecting the genome of the cell from insults of cancer-causing agents, such as those found in tobacco smoke. Reduced DNA repair capacity, therefore, can increase the susceptibility to smoking-related cancers. Recently, three coding polymorphisms in X-ray cross-complementing group 1 (XRCC1) DNA repair gene have been identified, and it is possible that these polymorphisms may affect DNA repair capacity and thus modulate cancer susceptibility. We investigated the relationship between the codon 399 polymorphism in XRCC1 gene and lung cancer risk in male smokers. The study population consisted of 192 lung cancer patients and 135 healthy controls. The distribution of XRCC1 genotypes was not significantly different between cases and controls. When the cases were categorized by histological type, however, the presence of at least one Gln allele was associated with a significant increased risk for squamous cell carcinoma [crude odds ratio (OR) = 1.77, 95% confidence interval (CI) = 1.06-2.93 and adjusted OR = 1.66, 95% CI = 0.99-2.79]. The risk for the disease increased as the number of Gln alleles increased (Arg/Gln genotype: adjusted OR = 1.45, 95% CI = 0.84-2.5; Gln/Gln genotype: adjusted OR = 3.26, 95% CI = 1.17-9.15). When the subjects dichotomized by cigarette consumption into two pack-year groups (< or =40 pack-years, >40 pack-years), the Gln allele was associated with an increased risk for squamous cell carcinoma only in the group of individuals having < or =40 pack-years of smoking (Arg/Gln genotype: adjusted OR = 1.48, 95% CI = 0.78-2.8; Gln/Gln genotype: adjusted OR = 5.75, 95% CI = 1.46-22.69). These results suggest that XRCC1 codon 399 polymorphism may be an important genetic determinant of squamous cell carcinoma of the lung in persons with lower degrees of cigarette use. 相似文献
948.
Because insulin-like growth factor-1 (IGF-1) counteracts the anti-neoplastic effect of cisplatin that induces DNA damage and cell death through the formation of platinum-DNA adducts, we investigated the effects of IGF-1 on the DNA double-strand breaks (DSBs) repair system induced by cisplatin. NCI-H1299 and H460 non-small cell lung cancer (NSCLC) cells treated with IGF-1 recovered from cisplatin-derived inhibited proliferation and apoptosis. Decreased tail length in comet assay and suppressed phosphorylation of histone H2AX at Ser139 with IGF-1 cotreatment indicates that IGF-1 attenuates cisplatin-induced DNA damage. Cotreatment with IGF-1 attenuates phosphorylation of ataxia-telangiectasia mutated (ATM) at Ser1981, and ATM-Rad3-related (ATR) at Ser428 and subsequent phosphorylation of Chk2, Chk1, and p53 also dwindled by IGF-1. On the other hand, suppression of the IGF system with AG1024 or siRNA of insulin receptor substrate-1 (IRS-1), a major adaptor molecule of the IGF system, augmented cisplatin-induced gammaH2AX, Ser1981-pATM, and Ser428-pATR generation. ATM, which plays an important role in the phosphorylation of histone H2AX and Chk2 at Thr68, strongly binds with IRS-1 under the influence of cisplatin, and the interaction was partially inhibited by IGF-1. Immunocytochemistry revealed that cisplatin induces nuclear translocation of IRS-1 with Ser1981-pATM, which is suppressed by cotreatment with IGF-1. In conclusion, cisplatin-induced gammaH2AX formation, DNA DSBs repair, and damage checkpoint pathway is inhibited by IGF-1. Cisplatin derives interaction between ATM and IRS-1, which is suppressed by IGF-1. Modulation of biologic activity of the IGF-1 system could be a promising modality that raises the response rate of conventional chemotherapy. 相似文献
949.
Se-Il Go Anna Lee Un Seok Lee Hye Jung Choi Myung Hee Kang Jung-Hun Kang Kyung Nyeo Jeon Mi Jung Park Seok-Hyun Kim Gyeong-Won Lee 《Lung cancer (Amsterdam, Netherlands)》2014
Background
The neutrophil–lymphocyte ratio (NLR) has been identified as a potentially useful marker for predicting clinical outcome in patients with cardiovascular disease, diabetes, and various malignancies. The aim of this study was to determine whether NLR at the time of venous thromboembolism (VTE) diagnosis is a prognostic factor for the response to anticoagulation and survival in lung cancer patients treated with anticoagulation for VTE.Patients and methods
We retrospectively analyzed the clinical characteristics, laboratory parameters, and NLR in 114 lung cancer patients newly diagnosed with VTE, among 991 patients pathologically confirmed for lung cancer between July 2008 and August 2013.Results
High NLR was significantly associated with high hematocrit (p = 0.028), high C-reactive protein (p = 0.002), and low albumin (p = 0.001). Compared with the low NLR group, stage IV non-small cell lung cancer (NSCLC) at the time of VTE diagnosis (55.6 vs. 74.6%, p = 0.055), central nervous system metastasis (5.8 vs. 25.8%, p = 0.004), and cancer progression (14.3 vs. 38.8%, p = 0.008) at the time of VTE diagnosis were also significant in the high NLR group. Moreover, the poor response to anticoagulation was statistically correlated with patients with NSCLC (p = 0.037), high NLR (p = 0.004), and low albumin (p = 0.029).Conclusions
The results demonstrate that the NLR at the time of VTE diagnosis could be a useful biomarker for predicting the response and prognosis following anticoagulation in patients with lung cancer and VTE. 相似文献950.
Jeon GA Lee JS Patel V Gutkind JS Thorgeirsson SS Kim EC Chu IS Amornphimoltham P Park MH 《International journal of cancer. Journal international du cancer》2004,112(2):249-258
For genomewide monitoring and identification of biomarkers of head and neck squamous cell carcinoma (HNSCC), we have conducted a systematic characterization of gene expression profiles, using human cDNA microarrays containing 9K clones, in 25 HNSCC cell lines and 1 immortalized human oral keratinocyte cell line. We used normal human oral keratinocytes (NHOKs) as a reference. Our study showed that genes primarily involved in cell cycle regulation, oncogenesis, cell proliferation, differentiation, apoptosis and cell adhesion were widely altered in the 26 cell lines. Upregulated genes included known oncogenes, protein kinases, DNA-binding proteins and cell cycle regulators, while those commonly downregulated included differentiation markers, cell adhesion proteins, extracellular matrix proteins, structural proteins (keratins) and protease inhibitor proteins. Compared to NHOK, we observed a striking reduction in the expression of genes involved in terminal differentiation, suggesting that a loss in this process is an important signature of HNSCC. In addition, hierarchical clustering analysis as well as principal component analysis revealed 2 distinctive subtypes of gene expression patterns among the 26 cell lines, reflecting a degree of heterogeneity in HNSCC. By applying significance analysis of microarrays, 128 genes were selected for being distinctively expressed between the 2 groups. Genes differentially expressed in the 2 subgroups include cell proliferation-related genes, IGFBP6, EGFR and VEGFC; tumor suppression and apoptosis-related genes such as Tp53, Tp63; as well as cell cycle regulators such as CCND1 and CCND2 (cyclins D1 and D2), suggesting that the 2 subgroups might have undergone different pathways of carcinogenesis. 相似文献