Publications by authors named "Yixing Chen"

35 Publications

Induction Strategy for Locally Advanced Thymoma.

Front Oncol 2021 22;11:704220. Epub 2021 Jul 22.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai, China.

Surgery remains cornerstone for the management of thymoma. Complete surgical resection (R0), is recognized as the constant and significant factor for prognosis. However, in locally advanced (Masaoka-Koga stages III-IVa) thymomas, achieving R0 resection remains challenging due to local-regional invasion of the disease. Induction treatment, with the aim of reducing bulky tumor mass, offers new strategy to facilitate totally surgical resection. Herein, we reviewed recent progress and provided a comprehensive overview of induction strategy in locally advance thymoma.
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http://dx.doi.org/10.3389/fonc.2021.704220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8339962PMC
July 2021

Exploration of the molecular targets and mechanisms of suxiao xintong dropping pills for myocardial infarction by network pharmacology method.

Biosci Rep 2021 Aug;41(8)

Department of Cardiology, Affiliated Nanping First Hospital, Fujian Medical University, Nanping 353000, Fujian Province, China.

Background: Suxiao Xintong dropping pills (SXXTDP), a traditional Chinese medicine, is widely applied for treating myocardial infarction (MI). However, its therapy mechanisms are still unclear. Therefore, this research is designed to explore the molecular mechanisms of SXXTDP in treating MI.

Methods: The active ingredients of SXXTDP and their corresponding genes of the active ingredients were retrieved from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. MI-related genes were identified via analyzing the expression profiling data (accession number: GSE97320). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed to study the shared genes of drug and disease. Through protein-protein interaction (PPI) network and the Cytoscape plugin cytoHubba, the hub genes were screened out. The compounds and hub targets binding were simulated through molecular docking method.

Results: We obtained 21 active compounds and 253 corresponding target genes from TCMSP database. 1833 MI-related genes were identified according to P<0.05 and |log2FC| ≥ 0.5. 27 overlapping genes between drug and disease were acquired. GO analysis indicated that overlapping genes were mainly enriched in MAP kinase activity and antioxidant activity. KEGG analysis indicated that overlapping genes were mainly enriched in IL-17 signaling pathway and TNF signaling pathway. We obtained 10 hub genes via cytoHubba plugin. Six of the 10 hub genes, including PTGS2, MAPK14, MMP9, MAPK1, NFKBIA, and CASP8, were acted on molecular docking verification with their corresponding compounds of SXXTDP.

Conclusion: SXXTDP may exert cardioprotection effect through regulating multiple targets and multiple pathways in MI.
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http://dx.doi.org/10.1042/BSR20204211DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8350434PMC
August 2021

Blocking the CCL5-CCR5 Axis Using Maraviroc Promotes M1 Polarization of Macrophages Cocultured with Irradiated Hepatoma Cells.

J Hepatocell Carcinoma 2021 18;8:599-611. Epub 2021 Jun 18.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China.

Purpose: The C-C chemokine ligand 5 (CCL5)-C-C chemokine receptor (CCR5) axis facilitates tumor progression via multiple mechanisms. Herein, we elucidated the effect of a CCR5 antagonist (maraviroc [MVC]; blocking the CCL5-CCR5 axis) on the phenotype of macrophages cocultured with irradiated hepatoma cells. In addition, we investigated whether modulation of macrophage polarization can alter tumor cell sensitivity to radiation.

Materials And Methods: Quantitative reverse-transcription polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assays were applied to examine the levels of macrophage-associated markers. The mechanisms of macrophage polarization were explored by Western blotting in an in vitro model of coculture of human hepatoma cells with macrophages. The radiation sensitivity was examined in a clonogenic radiosensitivity assay. Tumor cell apoptosis was detected by Western blotting and flow cytometry. A mouse model of a subcutaneous tumor was also established.

Results: CCL5 skewed THP-1 M0 macrophages toward an M2-like phenotype. In coculture with hepatoma cells, macrophages manifested high levels of interleukin (IL) 10, IL-12, tumor necrosis factor α (TNF-α), transforming growth factor β1 (TGF-β1), arginase 1 (ARG1), and IL-1β. Tumor cell irradiation further upregulated these markers in macrophages. After incubation of macrophages with MVC for 24 h, levels of M1 cytokines significantly increased, whereas those of M2 phenotype factors ARG1, TGF-β1, and IL-10 decreased, accompanied by the activation of signal transducer and activator of transcription 3 (STAT3) and downregulation of suppressor of cytokine signaling 3 (SOCS3). The macrophage phenotype reverted to M2 states after treatment with a STAT3 inhibitor. The shift of macrophages toward the M1 phenotype enhanced the radiosensitivity and apoptosis of hepatoma cells. Mice receiving a combination of X-ray irradiation and MVC experienced a better antitumor effect than those receiving either MVC or irradiation alone did.

Conclusion: M2 polarization of macrophages induced by CCL5-CCR5 signaling can be inhibited using MVC via the STAT3-SOCS3 pathway. The shift of macrophages toward the M1 phenotype promotes the sensitivity of human hepatoma cells to X-ray irradiation.
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http://dx.doi.org/10.2147/JHC.S300165DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8219307PMC
June 2021

OVOL2 attenuates the expression of MAP3K8 to suppress epithelial mesenchymal transition in colorectal cancer.

Pathol Res Pract 2021 Aug 25;224:153493. Epub 2021 May 25.

Laboratory of Cancer Center, The First Affiliated Hospital of Xiamen University, Xiamen, China; Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, Xiamen, China. Electronic address:

Background: Inactivation of members of the OVO-like family of C2H2 zinc-finger transcription factor 2 (OVOL2) is increased after colorectal cancer (CRC) metastasis. This study investigated the functional roles and clinical relevance of OVOL2 and its downstream factors in colorectal carcinogenesis.

Methods: Transcriptome RNA sequencing (RNA-seq) of HCT116 cells overexpressing OVOL2 and SW480 cells silencing OVOL2 were conducted. We cross-checked the Chromatin Immunoprecipitation sequencing (ChIP-seq, GSM1239518) positive peaks and RNA-seq differential expression genes (DEGs). In vitro functional assays, including wound-healing assay and transwell assay, were performed. The RNA expression (n = 597) and protein expression (n = 93) of OVOL2- mitogen-activated protein kinase kinase kinase 8 (MAP3K8)-C-X-C Motif Chemokine Ligand 16 (CXCL16) were evaluated in human CRC and adjacent normal tissues. CXCL16 levels in cell culture supernatants and serum samples obtained from 29 colon polyps patients and 24 CRC patients were measured using ELISA.

Results: We found that OVOL2 inhibited the migration and epithelial mesenchymal transition (EMT) of CRC cells by blocking the MAP3K8/AKT/NF-κB signaling pathway, and also decreased levels of CXCL16, a chemokine downstream of the MAP3K8/AKT/NF-κB signaling pathway. Furthermore, patient tumor tissue samples showed a lower level of in situ OVOL2 (P = 0.005) and higher CXCL16 (P = 0.001) levels, compared to adjacent normal tissues. Survival analyses revealed that both OVOL2 (logrank P = 0.063) and CXCL16 (logrank P = 0.048) were associated with overall survival (OS) and were independent prognostic factors for CRC. Additionally, OVOL2 and CXCL16 were found to be prognostically relevant (logrank P = 0.038). CXCL16 may serve as a potential diagnostic biomarker for CRC (P = 0.010).

Conclusions: The OVOL2/ MAP3K8/CXCL16 axis is a key player in colonic tumorigenesis and metastasis, and may be a potential diagnostic and prognostic biomarker.
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http://dx.doi.org/10.1016/j.prp.2021.153493DOI Listing
August 2021

MiR-3130-5p is an intermediate modulator of 2q33 and influences the invasiveness of lung adenocarcinoma by targeting NDUFS1.

Cancer Med 2021 06 12;10(11):3700-3714. Epub 2021 May 12.

National Institute for Data Science in Health and Medicine, School of Medicine, Xiamen University, Xiamen, China.

Genome-wide association studies (GWAS) have reported a handful of loci associated with lung cancer risk, of which the pathogenic pathways are largely unknown. We performed cis-expression quantitative trait loci (eQTL) mapping for 376 lung cancer related GWAS loci in 227 TCGA lung adenocarcinoma (LUAD) and reported two risk loci as eQTL of miRNA. Among the miRNAs in association with lung cancer risk, we further predicted and validated miR-3130-5p as an intermediate modulator of risk loci 2q33 and the tumor suppressor NDUFS1. We assessed the phenotypic impacts of the interaction between miR-3130-5p and NDUFS1 in both lung cancer cell lines and mice xenograft models. As a result, miR-3130-5p directly regulates the expression of NDUFS1 and the corresponding tumor invasiveness, migration and epithelial-mesenchymal transition (EMT). Our findings provide important clues for the pathogenic mechanism of 2q33 in lung carcinogenesis which informs clinical diagnosis and prognosis of LUAD. We performed a cis-eQTL analysis for 376 lung cancer risk loci based on the expression profiles of 251 miRNAs in a cohort of 227 TCGA lung adenocarcinoma. We report a novel pathogenic pathway of 2q33 via miR-3130-5p and NDUFS1.
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http://dx.doi.org/10.1002/cam4.3885DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8178510PMC
June 2021

Integration of radiotherapy with anti-PD-1 antibody for the treatment of intrahepatic or hilar cholangiocarcinoma: reflection from four cases.

Cancer Biol Ther 2021 03 15;22(3):175-183. Epub 2021 Mar 15.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai, China.

Cholangiocarcinoma (CCA) represents a clinically challenging disease with a dismal prognosis. A therapeutic plateau has been reached with traditional treatments. However, with immunotherapy advances in cancer therapy, integration of stereotactic body radiotherapy (SBRT) with anti-PD-1 antibody shows a synergistic effect and high clinical efficacy in many cancer types. This combination may represent a breakthrough in the treatment of this fatal malignancy. Here, we report four cases of refractory advanced intrahepatic or hilar cholangiocarcinoma that were successfully controlled with anti-PD-1 antibody following or concurrent with SBRT. Furthermore, one case was initially unresectable; however, following this novel combined therapy, it became operable. We discuss the challenges of developing predictive biomarkers for anti-PD-1 antibody responsiveness. We also consider the regulatory effect of SBRT on the tumor microenvironment and the potential advantages of this therapy combination for treatment of intrahepatic or hilar cholangiocarcinoma. These are important considerations and provide direction for future clinical trial designs.
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http://dx.doi.org/10.1080/15384047.2020.1834792DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8043185PMC
March 2021

Novel Application of Predictive Modeling: A Tailored Approach to Promoting HCC Surveillance in Patients With Cirrhosis.

Clin Gastroenterol Hepatol 2021 Mar 2. Epub 2021 Mar 2.

Department of Population Sciences, University of Texas Southwestern Medical Center and Parkland Health & Hospital, Dallas, Texas; Harold C. Simmons Cancer Center, University of Texas Southwestern Medical Center and Parkland Health & Hospital, Dallas, Texas.

Objective: There has been increased interest in interventions to promote hepatocellular carcinoma (HCC) surveillance given low utilization and high proportions of late stage detection. Accurate prediction of patients likely versus unlikely to respond to interventions could allow a cost-effective approach to outreach and facilitate targeting more intensive interventions to likely non-responders.

Design: We conducted a secondary analysis of a randomized clinical trial evaluating a mailed outreach strategy to promote HCC surveillance among 1200 cirrhosis patients at a safety-net health system between December 2014 and March 2017. We developed regularized logistic regression (RLR) and gradient boosting machine (GBM) algorithm models to predict surveillance completion during each of the 3 screening rounds in a training set (n = 960). Model performance was assessed using multiple performance metrics in an independent test set (n = 240).

Results: Among 1200 patients, surveillance was completed in 41-47% of patients over the three rounds. The RLR and GBM models demonstrated good discriminatory accuracy, with area under receiver operating characteristic (AUROC) curves of 0.67 and 0.66 respectively in the first surveillance round and improved to 0.77 by the third surveillance round after incorporating prior screening behavior as a feature. Additional performance characteristics including the Brier score, Hosmer-Lemeshow test and reliability diagrams were also evaluated. The most important variables for the predictive model were prior screening completion status and past primary care contact.

Conclusions: Predictive models can help stratify patients' likelihood to respond to surveillance outreach invitations, facilitating tailored strategies to maximize effectiveness and cost-effectiveness of HCC surveillance population health programs.
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http://dx.doi.org/10.1016/j.cgh.2021.02.038DOI Listing
March 2021

Auxin apical dominance governed by the OsAsp1-OsTIF1 complex determines distinctive rice caryopses development on different branches.

PLoS Genet 2020 10 27;16(10):e1009157. Epub 2020 Oct 27.

Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, China.

In rice (Oryza sativa), caryopses located on proximal secondary branches (CSBs) have smaller grain size and poorer grain filling than those located on apical primary branches (CPBs), greatly limiting grain yield. However, the molecular mechanism responsible for developmental differences between CPBs and CSBs remains elusive. In this transcriptome-wide expression study, we identified the gene Aspartic Protease 1 (OsAsp1), which reaches an earlier and higher transcriptional peak in CPBs than in CSBs after pollination. Disruption of OsAsp1 expression in the heterozygous T-DNA line asp1-1+/-eliminated developmental differences between CPBs and CSBs. OsAsp1 negatively regulated the transcriptional inhibitor of auxin biosynthesis, OsTAA1 transcriptional inhibition factor 1 (OsTIF1), to preserve indole-3-acetic acid (IAA) apical dominance in CPBs and CSBs. IAA also facilitated OsTIF1 translocation from the endoplasmic reticulum (ER) to the nucleus by releasing the interaction of OsTIF1 with OsAsp1 to regulate caryopses IAA levels via a feedback loop. IAA promoted transcription of OsAsp1 through MADS29 to maintain an OsAsp1 differential between CPBs and CSBs during pollination. Together, these findings provide a mechanistic explanation for the distributed auxin differential between CPBs and CSBs to regulate distinct caryopses development in different rice branches and potential targets for engineering yield improvement in crops.
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http://dx.doi.org/10.1371/journal.pgen.1009157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7647119PMC
October 2020

Pharmacological Inhibition of Necroptosis Promotes Human Breast Cancer Cell Proliferation and Metastasis.

Onco Targets Ther 2020 16;13:3165-3176. Epub 2020 Apr 16.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032, People's Republic of China.

Background: Breast cancer remains a great threat to females worldwide. As a recently defined programmed cell death pathway that associates with immune activation, RIP1/RIP3/MLKL necroptosis signaling has been implicated in a variety of diseases. The present study aimed to investigate the role of RIP1/RIP3/MLKL signaling in breast cancer cell proliferation and metastasis in vivo and in vitro.

Methods: Western blot and quantitative real-time PCR were performed to evaluate the activation of necroptosis signaling in clinical human breast cancer tissues. Correlation of necroptosis signaling markers with clinicopathological parameters was statistically assessed. Cell viability assay, colony formation assay, wound healing assay, and transwell migration and invasion assays were performed to investigate the effects of necroptosis inhibition on breast cancer cell proliferation and metastasis.

Results: Clinical breast cancer tissues showed significantly higher levels of tumor necrosis factor alpha (TNFα), RIP1, RIP3 and MLKL at both mRNA and protein levels as compared with their paired non-cancerous tissues. Phosphorylation of RIP3 and MLKL was also remarkably provoked. Statistics showed that both RIP1 and MLKL positively correlated with cancer parameters such as N-cadherin (=0.002 for RIP1 and =0.021 for MLKL) and Ki67 (=0.031 for RIP1 and =0.05 for MLKL). The MLKL expression level significantly correlated with tumor size (=0.001) and the proliferation indicator Ki67 (=0.018). In addition, pharmacological inhibition of the necroptosis signaling using necrostatin-1 promoted breast cancer cell proliferation and colony formation by approximately 50%. Blockade of necroptosis signaling also accelerated wound healing process and cell transmigration in breast cancer cells.

Conclusion: Our results suggested that pharmacological inhibition of necroptosis promoted breast cancer cell proliferation and metastasis. Modulation of tumor cell necroptosis might represent a novel strategy as to breast cancer treatment.
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http://dx.doi.org/10.2147/OTT.S246899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7170643PMC
April 2020

DNA sensing and associated type 1 interferon signaling contributes to progression of radiation-induced liver injury.

Cell Mol Immunol 2021 Jul 19;18(7):1718-1728. Epub 2020 Mar 19.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.

Liver damage upon exposure to ionizing radiation (IR), whether accidental or therapeutic, can contribute to liver dysfunction. Currently, radiotherapy (RT) is used for various cancers including hepatocellular carcinoma (HCC); however, the treatment dose is limited by radiation-induced liver disease (RILD) with a high mortality rate. Furthermore, the precise molecular mechanisms of RILD remain poorly understood. Here, we investigated RILD pathogenesis using various knockout mouse strains subjected to whole-liver irradiation. We found that hepatocytes released a large quantity of double-stranded DNA (dsDNA) after irradiation. The cGAS-STING pathway in non-parenchymal cells (NPCs) was promptly activated by this dsDNA, causing interferon (IFN)-I production and release and concomitant hepatocyte damage. Genetic and pharmacological ablation of the IFN-I signaling pathway protected against RILD. Moreover, clinically irradiated human peri-HCC liver tissues exhibited substantially higher STING and IFNβ expression than non-irradiated tissues. Increased serum IFNβ concentrations post-radiation were associated with RILD development in patients. These results delineate cGAS-STING induced type 1 interferon release in NPCs as a key mediator of IR-induced liver damage and described a mechanism of innate-immunity-driven pathology, linking cGAS-STING activation with amplification of initial radiation-induced liver injury.
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http://dx.doi.org/10.1038/s41423-020-0395-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8245603PMC
July 2021

APOE4 exacerbates α-synuclein pathology and related toxicity independent of amyloid.

Sci Transl Med 2020 02;12(529)

Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA.

The apolipoprotein E () ε4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease mainly by driving amyloid-β pathology. Recently, has also been found to be a genetic risk factor for Lewy body dementia (LBD), which includes dementia with Lewy bodies and Parkinson's disease dementia. How drives risk of LBD and whether it has a direct effect on α-synuclein pathology are not clear. Here, we generated a mouse model of synucleinopathy using an adeno-associated virus gene delivery of α-synuclein in human APOE-targeted replacement mice expressing APOE2, APOE3, or APOE4. We found that APOE4, but not APOE2 or APOE3, increased α-synuclein pathology, impaired behavioral performances, worsened neuronal and synaptic loss, and increased astrogliosis at 9 months of age. Transcriptomic profiling in APOE4-expressing α-synuclein mice highlighted altered lipid and energy metabolism and synapse-related pathways. We also observed an effect of on α-synuclein pathology in human postmortem brains with LBD and minimal amyloid pathology. Our data demonstrate a pathogenic role of APOE4 in exacerbating α-synuclein pathology independent of amyloid, providing mechanistic insights into how increases the risk of LBD.
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http://dx.doi.org/10.1126/scitranslmed.aay1809DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8309690PMC
February 2020

Image-guided intensity-modulated radiotherapy improves short-term survival for abdominal lymph node metastases from hepatocellular carcinoma.

Ann Palliat Med 2019 Nov;8(5):717-727

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.

Background: Radiotherapy (RT) is an effective treatment for hepatocellular carcinoma (HCC) patients with lymph node metastasis (LNM), which is a rare clinical situation with a poor prognosis. We evaluated the responses and toxicities in HCC patients with abdominal LNM treated with either image-guided intensity-modulated radiotherapy (IG-IMRT) or non-IG-IMRT.

Methods: Retrospective review of the records of HCC patients with regional LNM treated with IG-IMRT (n=43) or non-IG-IMRT (n=42). The tumor responses, local control rates (LCRs), overall survival (OS) rates, and toxicities were evaluated.

Results: The mean biological effective dose with α/β =10 Gy (BED10) delivered to IG-IMRT group was 67.23±8.48 vs. 63.43±5.01 Gy delivered to non-IG-IMRT group (P=0.008). OS in IG-IMRT group vs. non-IG-IMRT group was 15.3 vs. 9.7 months (P=0.098). The one-year survival of IG-IMRT group was superior (69% vs. 38.1% for non-IG-IMRT, P=0.006). Whereas two-year survival was not significantly different. Negative independent prognostic factors included ≥2 positive lymph nodes and previous treatment without surgery, while BED10 ≥65 Gy was a protective factor. Toxicities were mild for both groups, while IG-IMRT group showed less late hepatotoxicity.

Conclusions: The therapeutic dose delivered by IG-IMRT is slightly higher than non-IG-IMRT which was more effective and showed superior short-term survival and local control in HCC patients with LNM.
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http://dx.doi.org/10.21037/apm.2019.11.17DOI Listing
November 2019

Aldolase B impairs DNA mismatch repair and induces apoptosis in colon adenocarcinoma.

Pathol Res Pract 2019 Nov 16;215(11):152597. Epub 2019 Aug 16.

Department of Medical Oncology, Cancer Hospital, The First Affiliated Hospital of Xiamen University, Xiamen, China; Department of Clinical Medical, Fujian Medical University, Fuzhou, China; Department of Cancer Prevention Diagnosis and Treatment, Cancer Hospital, The First Affiliated Hospital of Xiamen University, Xiamen, China. Electronic address:

Evidence suggests that DNA repair capacity manifested by intact functional base excision repair and mismatch repair (MMR) pathways is related to the prognosis of multiple cancer types. Aldolase B (ALDOB) is well known for its role in metabolism and glycolysis. The expression of ALDOB in colon adenocarcinoma and the relationship between its expression and colon adenocarcinoma prognosis remain controversial; in addition, the potential role of ALDOB in DNA MMR has not yet been reported. In this study, we identified a cluster of DNA repair-related proteins that interact with ALDOB in the colon adenocarcinoma cell line HCT116. Expression analysis of colon adenocarcinoma data from the Cancer Genome Atlas (TCGA-COAD data, n = 551) indicated that ALDOB mRNA expression was significantly higher in specimens with microsatellite instability (MSI) than in specimens with microsatellite stability (MSS). Regarding prognosis, colon adenocarcinoma patients with high ALDOB mRNA expression had longer overall survival (OS). Higher expression of ALDOB protein was significantly correlated with MMR deficiency (d-MMR) in formalin-fixed paraffin-embedded (FFPE) patient specimens. The expression of ALDOB was significantly elevated in colon adenocarcinoma cell lines. Further evidence indicated that rather than affecting proliferation, ALDOB overexpression induced the functional loss of MMR proteins and in turn caused irreversible DNA damage via disrupting EZH2-Rad51 expression and then caused apoptosis by ERK inactivation. Overall, our study demonstrates that high ALDOB expression impairs DNA MMR and induces apoptosis in colon adenocarcinoma. ALDOB may be a new biomarker associated with d-MMR and an independent prognostic factor for colon adenocarcinoma.
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http://dx.doi.org/10.1016/j.prp.2019.152597DOI Listing
November 2019

OsCPK21 is required for pollen late-stage development in rice.

J Plant Physiol 2019 Sep 14;240:153000. Epub 2019 Jun 14.

Beijing Key Laboratory of Gene Resources and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China. Electronic address:

In flowering plants, pollen development is a critical step for reproductive success and necessarily involves complex genetic regulatory networks. Calcium-dependent protein kinases (CPKs) are plant-specific calcium sensors involved in the regulation of plant development and adaption to the environment; however, whether they play a role in regulating male reproduction remains elusive. Here, we found that the knockdown of spikelet-specific OsCPK21 causes pollen abortion in OsCPK21-RNAi transgenic plants. Severe defects in pollen development initiated at stage 10 of anther development and simultaneous cell death occurred in the pollen cells of OsCPK21-RNAi plants. Microarray analysis and qRT-PCR revealed that the transcription of OsCPK21 is coordinated with that of MIKC*-type MADS box transcription factors OsMADS62, OsMADS63, and OsMADS68 during rice anther development. We further showed that OsCPK21 indirectly up-regulates the transcription of OsMADS62, OsMADS63, and OsMADS68 through the potential MYB binding site, DRE/CRT element, and/or new ERF binding motif localised in the promoter region of these three MADS genes. These findings suggest that OsCPK21 plays an essential role in pollengenesis, possibly via indirectly regulating the transcription of MIKC*-type MADS box proteins.
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http://dx.doi.org/10.1016/j.jplph.2019.153000DOI Listing
September 2019

Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering.

J Chem Phys 2018 Jun;148(22):222835

Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.

The temperature dependence of the femtosecond elastic second harmonic scattering (fs-ESHS) response of bulk light and heavy water and their electrolyte solutions is presented. We observe clear temperature dependent changes in the hydrogen (H)-bond network of water that show a decrease in the orientational order of water with increasing temperature. Although DO has a more structured H-bond network (giving rise to more fs-ESHS intensity), the relative temperature dependence is larger in HO. The changes are interpreted in terms of the symmetry of H-bonds and are indicators of nuclear quantum effects. Increasing the temperature in electrolyte solutions decreases the influence of the total electrostatic field from ions on the water-water correlations, as expected from Debye-Hückel theory, since the Debye length becomes longer. The effects are, however, 1.9 times (6.3 times) larger than those predicted for HO (DO). Since fs-ESHS responses can be computed from known molecular coordinates, our observations provide a unique opportunity to refine quantum mechanical models of water.
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http://dx.doi.org/10.1063/1.5023343DOI Listing
June 2018

Aldolase A overexpression is associated with poor prognosis and promotes tumor progression by the epithelial-mesenchymal transition in colon cancer.

Biochem Biophys Res Commun 2018 03 15;497(2):639-645. Epub 2018 Feb 15.

Xiamen Diabetes Institution, The First Affiliated Hospital of Xiamen University, Xiamen, China. Electronic address:

There is increasing evidence that glycolysis is involved in cancer progression. Aldolase is a glycolytic enzyme that catalyzes the reversible conversion of fructose-1,6-bisphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. Disruption of the aldolase genes also plays a role in the progression of multiple types of cancer. However, the underlying mechanism of the action of aldolases in colon cancer progression remains elusive. In this study, aldolase A expression was investigated and found to be upregulated along with human colon cancer progression and metastasis at both the mRNA and protein levels in human colon cancer tissues. In addition, silencing aldolase A suppressed colon cancer cell proliferation and invasion and inhibited the EMT phenotype. Aldolase A protein expression in colon cancer was related to tumor location, tumor clinical stage and survival. Kaplan-Meier analysis showed that high aldolase A protein expression was associated with an unfavorable outcome. Moreover, aldolase A affected the development of colon cancer not only by affecting the glucose metabolism but also by interacting with the HIF-1 and other EMT-related signaling pathways; silencing aldolase A resulted in the reduced activity of these signaling pathways. These results indicate that aldolase A has additional non-glycolytic functions in transcriptional EMT regulation and may therefore have potential as a therapeutic target or a biomarker for identifying patients at risk for poorer survival.
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http://dx.doi.org/10.1016/j.bbrc.2018.02.123DOI Listing
March 2018

ADAM9 mediates the interleukin-6-induced Epithelial-Mesenchymal transition and metastasis through ROS production in hepatoma cells.

Cancer Lett 2018 05 10;421:1-14. Epub 2018 Feb 10.

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, 180 Feng Lin Road, Shanghai 200032, China. Electronic address:

Interleukin (IL)-6 has been implicated in the invasion and metastasis of hepatocellular carcinoma (HCC). However, the molecular events that mediate this process are poorly understood. Here, we showed that IL-6 promoted the epithelial-mesenchymal transition (EMT) in HCC cell lines, and upregulated a disintegrin and metalloprotease 9 (ADAM9) expression by activating the JNK signaling pathway. ADAM9 was upregulated in human HCCs which promoted HCC cell invasion and the EMT by interacting with NADPH oxidase 1 and inducing reactive oxygen species generation. Knockdown of ADAM9 inhibited the IL-6-induced EMT. Additionally, ADAM9 expression was positively correlated with IL-6 and Snail expression in human HCC specimens. Taken together, our results showed that ADAM9 is an important mediator of IL-6-induced HCC cell migration and invasion, and may provide a novel therapeutic target for HCC management.
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http://dx.doi.org/10.1016/j.canlet.2018.02.010DOI Listing
May 2018

The Molecular Mechanism of Nanodroplet Stability.

ACS Nano 2017 12 14;11(12):12111-12120. Epub 2017 Dec 14.

Laboratory for Fundamental BioPhotonics, Institutes of Bioengineering and Materials Science and Engineering, School of Engineering, and Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.

Mixtures of nano- and microscopic oil droplets in water have recently been rediscovered as miniature reaction vessels in microfluidic environments and are important constituents of many environmental systems, food, personal care, and medical products. The oil nanodroplet/water interface stabilized by surfactants determines the physicochemical properties of the droplets. Surfactants are thought to stabilize nanodroplets by forming densely packed monolayers that shield the oil phase from the water. This idea has been inferred from droplet stability measurements in combination with molecular structural data obtained from extended planar interfaces. Here, we present a molecular level investigation of the surface structure and stability of nanodroplets and show that the surface structure of nanodroplets is significantly different from that of extended planar interfaces. Charged surfactants form monolayers that are more than 1 order of magnitude more dilute than geometrically packed ones, and there is no experimental correlation between stability and surfactant surface density. Moreover, dilute negatively charged surfactant monolayers produce more stable nanodroplets than dilute positively charged and dense geometrically packed neutral surfactant monolayers. Droplet stability is found to depend on the relative cooperativity between charge-charge, charge-dipole, and hydrogen-bonding interactions. The difference between extended planar interfaces and nanoscale interfaces stems from a difference in the thermally averaged total charge-charge interactions in the two systems. Low dielectric oil droplets with a size smaller than the Debye length in oil permit repulsive interactions between like charges from opposing interfaces in small droplets. This behavior is generic and extends up to the micrometer length scale.
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http://dx.doi.org/10.1021/acsnano.7b05100DOI Listing
December 2017

Zwitterionic and Charged Lipids Form Remarkably Different Structures on Nanoscale Oil Droplets in Aqueous Solution.

Langmuir 2018 01 26;34(3):1042-1050. Epub 2017 Oct 26.

Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.

The molecular structure of zwitterionic and charged monolayers on small oil droplets in aqueous solutions is determined using a combined second harmonic and sum frequency study. From the interfacial vibrational signature of the acyl chains and phosphate headgroups as well as the response of the hydrating water, we find that zwitterionic and charged lipids with identical acyl chains form remarkably different monolayers. Zwitterionic phospholipids form a closely packed monolayer with highly ordered acyl tails. In contrast, the charged phospholipids form a monolayer with a low number density and disordered acyl tails. The charged headgroups are oriented perpendicular to the monolayer rather than parallel, as is the case for zwitterionic lipids. These significant differences between the two types of phospholipids indicate important roles of phospholipid headgroups in the determination of properties of cellular membranes and lipid droplets. The observed behavior of charged phospholipids is different from expectations based on studies performed on extended planar interfaces, at which condensed monolayers are readily formed. The difference can be explained by nanoscale related changes in charge condensation behavior that has its origin in a different balance of interfacial intermolecular interactions.
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http://dx.doi.org/10.1021/acs.langmuir.7b02896DOI Listing
January 2018

Calcium-dependent protein kinase 21 phosphorylates 14-3-3 proteins in response to ABA signaling and salt stress in rice.

Biochem Biophys Res Commun 2017 12 4;493(4):1450-1456. Epub 2017 Oct 4.

Beijing Key Laboratory of Gene Resources and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China. Electronic address:

The calcium-dependent protein kinases (CDPKs) are a class of plant-specific kinase that directly bind Ca and mediate the calcium-signaling pathways to play important physiological roles in growth and development. The rice genome contains 31 CDPK genes, one of which, OsCPK21, is known to modulate the abscisic acid (ABA) and salt stress responses in this crop; however, the molecular mechanisms underlying this regulation are largely unknown. In the present study, we performed yeast two-hybrid screening, glutathione S-transferase pull-down, co-immunoprecipitation, and bimolecular fluorescence complementation assays to confirm the interaction between OsCPK21 and one of its putative targets, Os14-3-3 (OsGF14e). We used an in vitro kinase assay and site-directed mutagenesis to verify that OsCPK21 phosphorylates OsGF14e at Tyr-138. We used real-time PCR to reveal that several ABA and salt inducible genes were more highly expressed in the OsCPK21-OE and OsGF14e WT-OE plants than in the mutant OsGF14e Y138A-OE and wild-type plants. These results suggest that OsCPK21 phosphorylates OsGF14e to facilitate the response to ABA and salt stress.
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http://dx.doi.org/10.1016/j.bbrc.2017.09.166DOI Listing
December 2017

Orientational ordering of water in extended hydration shells of cations is ion-specific and is correlated directly with viscosity and hydration free energy.

Phys Chem Chem Phys 2017 Sep;19(36):24678-24688

Laboratory for fundamental BioPhotonics (LBP), Institute of Bio-engineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.

Specific ion effects in aqueous solutions are investigated at the molecular, nanoscopic and macroscopic levels. Femtosecond elastic second harmonic scattering (fs-ESHS) is used here to assess the chemical effects of ions on molecular and nanoscopic length scales of water, probing changes in the charge distribution around ions as well as structural orientational order of water molecules in extended hydration shells. We measured >0.05 M electrolyte solutions with a series of chloride salts (LiCl, NaCl, KCl, CsCl, RbCl, NHCl, MgCl, CaCl, and SrCl). Ion specificity is observed in both the local electronic anisotropy and the nanoscopic orientational ordering of water. Both observables are influenced more by cations with larger valencies and smaller sizes and follow a direct Hofmeister trend. These ion-induced structural changes in the hydrogen-bond network of water are strongly correlated with the viscosity B-coefficient and the Gibbs free energy of hydration of ions. Such a connection between the nanoscopic and macroscopic changes provides a possibility to construct a molecular model for specific ion effects in aqueous solutions.
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http://dx.doi.org/10.1039/c7cp03395hDOI Listing
September 2017

Interfacial Structure and Hydration of 3D Lipid Monolayers in Aqueous Solution.

J Phys Chem B 2017 04 24;121(13):2808-2813. Epub 2017 Mar 24.

Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.

Three-dimensional (3D) phospholipid monolayers at hydrophobic surfaces are ubiquitous and found in nature as adiposome organelles or in man-made materials such as drug delivery systems. However, the molecular level understanding of such monolayers remains elusive. Here, we investigate the molecular structure of phosphatidylcholine (PC) lipids forming 3D monolayers on the surface of hexadecane nanodroplets. The effects of acyl chain length, saturation, and number of acyl tails per lipid were studied with vibrational sum frequency and second harmonic scattering techniques. We find that 1,2-dihexadecanoyl-sn-glycero-3-phosphocholine (DPPC) lipids form tightly packed monolayers. Upon shortening the tail length to 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC), more gauche defects are observed. Monolayers of unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and single acyl chained 1-palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine (lyso-PC) contain more disorder. Despite these variations in the packing, the headgroup orientation remained approximately parallel to the nanodroplet interface. Remarkably, the lyso-PC uniquely forms more diluted and "patchy" 3D monolayers.
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http://dx.doi.org/10.1021/acs.jpcb.7b00609DOI Listing
April 2017

Feasibility and efficacy of helical intensity-modulated radiotherapy for stage III non-small cell lung cancer in comparison with conventionally fractionated 3D-CRT.

J Thorac Dis 2016 May;8(5):862-71

Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.

Background: The standard treatment for stage III non-small-cell lung cancer (NSCLC) is still 60 Gy in conventional fractions combined with concurrent chemotherapy; however, the resulting local controls are disappointing. The aim of this study was to compare and assess the feasibility and efficacy of hypofractionated chemoradiotherapy using helical tomotherapy (HT) with conventional fractionation as opposed to using three-dimensional conformal radiotherapy (3D-CRT) for stage III NSCLC.

Methods: Sixty-nine patients with stage III (AJCC 7th edition) NSCLC who underwent definitive radiation treatment at our institution between July 2011 and November 2013 were reviewed and analyzed retrospectively. A dose of 60 Gy in 20 fractions was delivered in the HT group (n=34), whereas 60 Gy in 30 fractions in the 3D-CRT group (n=35). Primary endpoints were toxicity, overall response rate, overall survival (OS) and progression-free survival (PFS).

Results: The median follow-up period was 26.4 months. V20 (P=0.005), V30 (P=0.001), V40 (P=0.004), mean lung dose (P=0.000) and max dose of spinal cord (P=0.005) were significantly lower in the HT group than in the 3D-CRT group. There was no significant difference in the incidences of acute radiation pneumonitis (RP) ≥ grade 2 between the two groups, whereas the incidences of acute radiation esophagitis ≥ grade 2 were significantly lower in the HT group than in the 3D-CRT group (P=0.027). Two-year overall response rate was significantly higher in the HT group than in the 3D-CRT group (P=0.015). One- and 2-year OS rates were significantly higher in the HT group (95.0% and 68.7%, respectively) than in the 3D-CRT group (85.5% and 47.6%, respectively; P=0.0236). One- and 2-year PFS rates were significantly higher in the HT group (57.8% and 26.3%, respectively) than in the 3D-CRT group (32.7% and 11.4%, respectively; P=0.0351). Univariate analysis indicated that performance status (PS), T stage and radiotherapy technique were significant prognostic factors for both OS and PFS. Multivariate analysis indicated that PS and radiotherapy technique were independent prognostic factors of OS and PS was independent prognostic factor of PFS.

Conclusions: Hypofractionated chemoradiotherapy via HT can shorten the radiotherapy time without increasing treatment-related toxicity. The preliminary findings are that OS and PFS can be improved by hypofractionated chemoradiotherapy via HT for patients with stage III NSCLC.
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http://dx.doi.org/10.21037/jtd.2016.03.46DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4842790PMC
May 2016

Electrolytes induce long-range orientational order and free energy changes in the H-bond network of bulk water.

Sci Adv 2016 Apr 8;2(4):e1501891. Epub 2016 Apr 8.

Laboratory for fundamental BioPhotonics, Institutes of Bioengineering and Materials Science and Engineering, School of Engineering, and Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.

Electrolytes interact with water in many ways: changing dipole orientation, inducing charge transfer, and distorting the hydrogen-bond network in the bulk and at interfaces. Numerous experiments and computations have detected short-range perturbations that extend up to three hydration shells around individual ions. We report a multiscale investigation of the bulk and surface of aqueous electrolyte solutions that extends from the atomic scale (using atomistic modeling) to nanoscopic length scales (using bulk and interfacial femtosecond second harmonic measurements) to the macroscopic scale (using surface tension experiments). Electrolytes induce orientational order at concentrations starting at 10 μM that causes nonspecific changes in the surface tension of dilute electrolyte solutions. Aside from ion-dipole interactions, collective hydrogen-bond interactions are crucial and explain the observed difference of a factor of 6 between light water and heavy water.
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http://dx.doi.org/10.1126/sciadv.1501891DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4846452PMC
April 2016

Three Dimensional Nano "Langmuir Trough" for Lipid Studies.

Nano Lett 2015 Aug 10;15(8):5558-63. Epub 2015 Jul 10.

†Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.

A three-dimensional-phospholipid monolayer with tunable molecular structure was created on the surface of oil nanodroplets from a mixture of phospholipids, oil, and water. This simple nanoemulsion preparation technique generates an in situ prepared membrane model system with controllable molecular surface properties that resembles a lipid droplet. The molecular interfacial structure of such a nanoscopic system composed of hexadecane, 1,2-dihexadecanoyl-sn-glycero-3-phosphocholine (DPPC), and water was determined using vibrational sum frequency scattering and second harmonic scattering techniques. The droplet surface structure of DPPC can be tuned from a tightly packed liquid condensed phase like monolayer to a more dilute one that resembles the liquid condensed/liquid expanded coexistence phase by varying the DPPC/oil/water ratio. The tunability of the chemical structure, the high surface-to-volume ratio, and the small sample volume make this system an ideal model membrane for biochemical research.
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http://dx.doi.org/10.1021/acs.nanolett.5b02143DOI Listing
August 2015

Evaluation of the Antitumor Efficacy of RNAi-Mediated Inhibition of CDC20 and Heparanase in an Orthotopic Liver Tumor Model.

Cancer Biother Radiopharm 2015 Aug 1;30(6):233-9. Epub 2015 Jul 1.

1 Hepatobiliary Enteric Surgery Research Center, Xiangya Hospital, Central South University , Changsha, People's Republic of China .

Over 90% of patients with hepatocellular carcinoma (HCC) are diagnosed at an advanced stage. This study investigated the antitumor efficacy of the inhibition of cell division cycle protein 20 (CDC20) and heparanase (HPSE) expression in Hepa1-6 mouse hepatoma cells. Cell viability was measured by the MTT assay. Cell cycle was analyzed by cytometry. The invasion assay was performed using the Transwell chamber. The orthotopic liver tumor model was established by inoculating the livers of immunocompetent Kunming mice with Hepa1-6 cells. The MTT assay showed that 50 and 100 nM CDC20 siRNA-1 and HPSE siRNA-2 significantly reduced Hepa1-6 cell viability with the combination of CDC20 and HPSE siRNA being the most effective. Silencing of CDC20 or both CDC20 and HPSE expression significantly induced G2/M phase cell cycle arrest in Hepa1-6 HCC cells. Silencing HPSE expression significantly inhibited the invasion ability of Hepa1-6 cells with the combination of CDC20 and HPSE silencing being more effective than HPSE alone. Silencing CDC20 and HPSE expression significantly inhibited HCC tumor growth in the orthotopic liver tumor model, but the combination was most effective. Silencing CDC20 and HPSE expression activated cell apoptosis and autophagy. In conclusion, targeting inhibition of both CDC20 and HPSE expression is an ideal strategy for HCC therapy.
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http://dx.doi.org/10.1089/cbr.2014.1799DOI Listing
August 2015

Sum frequency and second harmonic generation from the surface of a liquid microjet.

J Chem Phys 2014 Nov;141(18):18C524

Laboratory for Fundamental Biophotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.

The use of a liquid microjet as a possible source of interest for Second Harmonic Generation (SHG) and Sum Frequency Generation (SFG) spectroscopy is examined. We measured non-resonant SHG scattering patterns from the air/water interface of a microjet of pure water and observe a strong enhancement of the SHG signal for certain scattering angles. These enhancements can be explained by the optical properties and the shape of the liquid microjet. SFG experiments at the surface of a liquid microjet of ethanol in air show that it is also possible to measure the coherent vibrational SFG spectrum of the ethanol/air interface in this way. Our findings are useful for future far-UV or X-ray based nonlinear optical surface experiments on liquid jets. In addition, combined X-ray photoelectron spectroscopy and SHG/SFG measurements are feasible, which will be very useful in improving our understanding of the molecular foundations of electrostatic and chemical surface properties and phenomena.
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http://dx.doi.org/10.1063/1.4896996DOI Listing
November 2014

Charge asymmetry at aqueous hydrophobic interfaces and hydration shells.

Angew Chem Int Ed Engl 2014 Sep 13;53(36):9560-3. Epub 2014 Jul 13.

Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Féderale de Lausanne (EPFL), 1015 Lausanne (Switzerland).

Guilty as charged: Water is often modeled as a dielectric continuum, but the molecular structure of water is asymmetric. Two ions that have a virtually identical size, shape, and structure, but an opposite charge sign have been investigated to see whether charge makes a fundamental difference to water structuring. The spectroscopic data for the hydration and interface structures are found to be remarkably different for opposite charges.
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http://dx.doi.org/10.1002/anie.201310266DOI Listing
September 2014

Hearing voices: evaluation of a medical student training experience about psychosis.

Acad Psychiatry 2014 Aug 3;38(4):514-5. Epub 2014 Jul 3.

University of Toledo College of Medicine, Toledo, OH, USA.

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http://dx.doi.org/10.1007/s40596-014-0166-zDOI Listing
August 2014

Specific ion effects in amphiphile hydration and interface stabilization.

J Am Chem Soc 2014 Feb 24;136(5):2040-7. Epub 2014 Jan 24.

Laboratory for Fundamental BioPhotonics (LBP), Institute of Bio-Engineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL) , Station 17, CH-1015 Lausanne, Switzerland.

Specific ion effects can influence many processes in aqueous solutions: protein folding, enzyme activity, self-assembly, and interface stabilization. Ionic amphiphiles are known to stabilize the oil/water interface, presumably by dipping their hydrophobic tails into the oil phase while sticking their hydrophilic head groups in water. However, we find that anionic and cationic amphiphiles adopt strikingly different structures at liquid hydrophobic/water interfaces, linked to the different specific interactions between water and the amphiphile head groups, both at the interface and in the bulk. Vibrational sum frequency scattering measurements show that dodecylsulfate (DS(-)) ions do not detectably perturb the oil phase while dodecyltrimethylammonium (DTA(+)) ions do. Raman solvation shell spectroscopy and second harmonic scattering (SHS) show that the respective hydration-shells and the interfacial water structure are also very different. Our work suggests that specific interactions with water play a key role in driving the anionic head group toward the water phase and the cationic head group toward the oil phase, thus also implying a quite different surface stabilization mechanism.
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http://dx.doi.org/10.1021/ja4120117DOI Listing
February 2014
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