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991.
992.
Can F. Koyuncu Cheng Lu Kaustav Bera Zelin Zhang Jun Xu Paula Toro German Corredor Deborah Chute Pingfu Fu Wade L. Thorstad Farhoud Faraji Justin A. Bishop Mitra Mehrad Patricia D. Castro Andrew G. Sikora Lester D.R. Thompson R.D. Chernock Krystle A. Lang Kuhs Jingqin Luo Vlad Sandulache David J. Adelstein Shlomo Koyfman James S. Lewis Jr. Anant Madabhushi 《The Journal of clinical investigation》2021,131(8)
BACKGROUNDPatients with p16+ oropharyngeal squamous cell carcinoma (OPSCC) are potentially cured with definitive treatment. However, there are currently no reliable biomarkers of treatment failure for p16+ OPSCC. Pathologist-based visual assessment of tumor cell multinucleation (MN) has been shown to be independently prognostic of disease-free survival (DFS) in p16+ OPSCC. However, its quantification is time intensive, subjective, and at risk of interobserver variability.METHODSWe present a deep-learning–based metric, the multinucleation index (MuNI), for prognostication in p16+ OPSCC. This approach quantifies tumor MN from digitally scanned H&E-stained slides. Representative H&E-stained whole-slide images from 1094 patients with previously untreated p16+ OPSCC were acquired from 6 institutions for optimization and validation of the MuNI.RESULTSThe MuNI was prognostic for DFS, overall survival (OS), or distant metastasis–free survival (DMFS) in p16+ OPSCC, with HRs of 1.78 (95% CI: 1.37–2.30), 1.94 (1.44–2.60), and 1.88 (1.43–2.47), respectively, independent of age, smoking status, treatment type, or tumor and lymph node (T/N) categories in multivariable analyses. The MuNI was also prognostic for DFS, OS, and DMFS in patients with stage I and stage III OPSCC, separately.CONCLUSIONMuNI holds promise as a low-cost, tissue-nondestructive, H&E stain–based digital biomarker test for counseling, treatment, and surveillance of patients with p16+ OPSCC. These data support further confirmation of the MuNI in prospective trials.FUNDINGNational Cancer Institute (NCI), NIH; National Institute for Biomedical Imaging and Bioengineering, NIH; National Center for Research Resources, NIH; VA Merit Review Award from the US Department of VA Biomedical Laboratory Research and Development Service; US Department of Defense (DOD) Breast Cancer Research Program Breakthrough Level 1 Award; DOD Prostate Cancer Idea Development Award; DOD Lung Cancer Investigator-Initiated Translational Research Award; DOD Peer-Reviewed Cancer Research Program; Ohio Third Frontier Technology Validation Fund; Wallace H. Coulter Foundation Program in the Department of Biomedical Engineering; Clinical and Translational Science Award (CTSA) program, Case Western Reserve University; NCI Cancer Center Support Grant, NIH; Career Development Award from the US Department of VA Clinical Sciences Research and Development Program; Dan L. Duncan Comprehensive Cancer Center Support Grant, NIH; and Computational Genomic Epidemiology of Cancer Program, Case Comprehensive Cancer Center. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, the US Department of VA, the DOD, or the US Government. 相似文献
993.
994.
Xueying Zheng Daizhi Yang Sihui Luo Jinhua Yan Xiaohui Guo Huixia Yang Wei Bao Leif Groop Anne Dornhorst Jianping Weng 《Diabetes care》2021,44(4):883
OBJECTIVETo investigate the effect on pregnancy outcome of integrating a comprehensive management plan for patients with type 1 diabetes (T1D) into the World Health Organization universal maternal care infrastructure.RESEARCH DESIGN AND METHODSA comprehensive preconception-to-pregnancy management plan for women with T1D was implemented in 11 centers from 8 Chinese cities from 2015 to 2017. Sequential eligible pregnant women (n = 133 out of 137 initially enrolled) with T1D and singleton pregnancies attending these management centers formed the prospective cohort. The main outcome was severe adverse pregnancy outcome comprising maternal mortality, neonatal death, congenital malformations, miscarriage in the second trimester, and stillbirth. We compared pregnancy outcomes in this prospective cohort with two control groups with the same inclusion and exclusion criteria: a retrospective cohort (n = 153) of all eligible pregnant women with T1D attending the same management centers from 2012 to 2014 and a comparison cohort (n = 116) of all eligible pregnant women with T1D receiving routine care from 2015 to 2017 in 11 different centers from 7 cities.RESULTSThe rate of severe adverse pregnancy outcome was lower in the prospective cohort (6.02%) than in either the retrospective cohort (18.30%; adjusted odds ratio [aOR] 0.31 [95% CI 0.13–0.74]) or the contemporaneous comparison cohort (25.00%; aOR 0.22 [95% CI 0.09–0.52]).CONCLUSIONSThe substantial improvements in the prospective cohort are evidence of a potentially clinically important effect of the comprehensive management plan on pregnancy outcomes among Chinese pregnant women with pregestational T1D. This supports the development of similar approaches in other countries. 相似文献
995.
996.
Yu‐Chen Han Zhong‐Liang Zheng Ze‐Hua Zuo Yan P Yu Rui Chen George C Tseng Joel B Nelson Jian‐Hua Luo 《The Journal of pathology》2013,230(2):184-193
Metallothioneins (MTs) are a group of metal binding proteins thought to play a role in the detoxification of heavy metals. Here we showed by microarray and validation analyses that MT1h, a member of MT, is down‐regulated in many human malignancies. Low expression of MT1h was associated with poor clinical outcomes in both prostate and liver cancer. We found that the promoter region of MT1h was hypermethylated in cancer and that demethylation of the MT1h promoter reversed the suppression of MT1h expression. Forced expression of MT1h induced cell growth arrest, suppressed colony formation, retarded migration, and reduced invasion. SCID mice with tumour xenografts with inducible MT1h expression had lower tumour volumes as well as fewer metastases and deaths than uninduced controls. MT1h was found to interact with euchromatin histone methyltransferase 1 (EHMT1) and enhanced its methyltransferase activity on histone 3. Knocking down of EHMT1 or a mutation in MT1h that abrogates its interaction with EHMT1 abrogated MT1h tumour suppressor activity. This demonstrates tumour suppressor activity in a heavy metal binding protein that is dependent on activation of histone methylation. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
997.
Xin Wang Xu Cao Bin Zhang Fei Liu Jianwen Luo Jing Bai 《Medical & biological engineering & computing》2013,51(1-2):7-17
Fluorescence molecular tomography is a promising imaging modality and has developed fast in the past years. However, challenges remain in its reconstruction, especially for the reconstruction accuracy and computational efficiency. Generally, an analytical method is computationally efficient while a numerical method has advantages in the reconstruction accuracy for arbitrary geometries. To achieve high reconstruction accuracy at low computational cost, a hybrid method that combines an analytical method based on Kirchhoff approximation (KA) and a numerical method based on finite element method (FEM) is proposed. This method is tested with numerical simulations and phantom experiments. Results of numerical simulations indicate that with the hybrid method, the reconstruction accuracy is improved while the computational time decreases by 40–70 % compared with the standalone KA method and FEM. Phantom experiments validate its feasibility for practical applications. 相似文献
998.
Teng Ma Yuqing Wang Fengyu Qi Shu Zhu Liangliang Huang Zhongyang Liu Jinghui Huang Zhuojing Luo 《Biomaterials》2013
Schwann cell (SC), which plays a key role in peripheral nerve regeneration, is one of the most classic supportive cells in neural tissue engineering. However, the biological activity of SCs seeded in nerve scaffolds decays subsequently due to local hypoxia induced by ischemia. Thus, we aimed to investigate whether a synthetic oxygen carrier-enriched fibrin gel would provide a sustained oxygen release to cultured SCs in vitro for overcoming a temporary (48 h) oxygen deprivation. In this study, perfluorotributylamine (PFTBA)-based oxygen carrying fibrin gel was prepared to provide oxygen for SCs under normoxic or hypoxic conditions. The dissolved oxygen within the culture media was measured by a blood-gas analyzer to quantify the time course of oxygen release from the PFTBA-enriched fibrin gel. SCs were cultured in the presence or absence of PFTBA-enriched fibrin gel under normoxic or hypoxic conditions. The tolerance of SCs to hypoxia was examined by a cell apoptosis assay. The growth of cells was characterized using S-100 staining and a CCK-8 assay. The migration of cells was examined using a Transwell chamber. The mRNA of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell derived neurotrophic factor (GDNF), neural cell adhesion molecule (N-CAM) and vascular endothelial growth factor (VEGF) in SCs were assayed by RT-PCR. In addition, SCs cultured in 3D PFTBA-enriched hydrogel were characterized by Live/Dead staining and the mRNA levels of BDNF, NGF, GDNF, N-CAM and VEGF were assayed by RT-PCR. The results showed that the PFTBA-enriched fibrin hydrogel was able to promote cell adhesion, migration, and proliferation under hypoxic conditions. Interestingly, PFTBA applied through the fibrin hydrogel dramatically enhanced the mRNA of BDNF, NGF, GDNF, N-CAM and VEGF under hypoxic condition. These findings highlight the possibility of enhancing nerve regeneration in cellular nerve grafts through PFTBA increased neurotropic secretion in SCs. 相似文献
999.
Shimao Song Shengming Zhu Zhiguo Zhang Zhengying Mo Qing Ke Zhiguo Luo 《African journal of traditional, complementary, and alternative medicines》2013,10(6):435-438
The objective of this paper was to investigate the antitumour mechanism of action of matrine by studying its inhibitory effect on gastric cancer SGC-7901 cells. SGC-7901 cells were chosen, and cell-killing capacity of matrine on gastric cancer SGC-7901 cells was determined using MTT assay and single PI staining assay. The results showed that matrine had an inhibitory effect on gastric cancer SGC-7901 cells, which was somewhat dose-dependent. The study concluded that matrine has a significant in-vitro inhibitory effect on SGC-7901 tumour cells, influences cell cycle of SGC-7901 cells, and induces their apoptosis. 相似文献
1000.
Honglin Zhu Hui Luo Yisha Li Yaou Zhou Ying Jiang Jin Chai Xianzhong Xiao Yunhui You Xiaoxia Zuo 《Journal of clinical immunology》2013,33(6):1100-1109
Uncontrolled fibrosis in multiple organs is the main cause of death in systemic sclerosis (SSc), and transforming growth factor-β (TGF-β) activation plays a fundamental role in the process. Our previous study demonstrated that miR-21 was significantly up-regulated in SSc fibroblasts. Here, we found that TGF-β regulated the expression of miR-21 and fibrosis-related genes, and decreased Smad7 expression. Over-expression of miR-21 in fibroblasts decreased the levels of Smad7, whereas knockdown of miR-21 increased its expression. Further study using a reporter gene assay demonstrated Smad7 was a direct target of miR-21. Similar to human SSc, the expression of miR-21 increased in the bleomycin induced skin fibrosis. Inhibition of fibrosis by treatment with anti-fibrosis drug bortezomib restored the levels of miR-21 and Smad7. MiR-21 may function in an amplifying circuit to enhance TGF-β signaling events in SSc fibrosis, and suggesting that miR-21 may act as a potential therapeutic target. 相似文献