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1.  Vibrational Excitations and Low Energy Electronic Structure of Epoxide-decorated Graphene 
We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.
doi:10.1021/jz4025386
PMCID: PMC3929940  PMID: 24563725
epitaxial graphene; oxygen; adsorbates; vibrations; band structure; reduced graphene oxide
2.  Correlation of endogenous hormonal levels, fibroglandular tissue volume and percent density measured using 3D MRI during one menstrual cycle 
Annals of Oncology  2013;24(9):2329-2335.
Background
We measured breast density (BD) on MRI and correlated with endogenous hormonal levels.
Patients and methods
Twenty-four premenopausal women received four weekly breast MRI. A blood sample was collected on the same day of MRI. BD was measured using a computer-based algorithm. The generalized estimation equation method was applied to model mean fibroglandular tissue volume (FV) and mean percent density (PD) from predictor variables including estradiol, progesterone, and week during a cycle.
Results
In week 3, a borderline significant correlation between estradiol and PD (r = 0.43, P = 0.04), estradiol and FV (r = 0.40, P = 0.05) and between progesterone and FV (r = 0.42, P = 0.04) was noted. The FV and PD measured in weeks 4 and 1 were higher than in weeks 2 and 3, adjusted for variation in endogenous estradiol and progesterone, indicating that the hormone change could not account for the changes in density. No lag effect of endogenous hormone on the change of FV or PD was noted (all P-values > 0.05).
Conclusions
Our results showed that BD is not strongly associated with the endogenous hormone. Their association with breast cancer risk was likely coming from different mechanisms, and they should be considered as independent risk factors.
doi:10.1093/annonc/mdt158
PMCID: PMC3755325  PMID: 23661294
breast density; endogenous hormone; fibroglandular tissue volume; lag effect; MRI; percent density
3.  Consistency of breast density measured from the same women using different MR scanners 
Annals of Oncology  2011;22(12):2693-2694.
doi:10.1093/annonc/mdr456
PMCID: PMC3221515  PMID: 22015449
5.  Stereotactic core biopsy of an impalpable screen-detected breast lesion using acupuncture-analgesia 
The British Journal of Radiology  2010;83(994):e208-e210.
Chinese acupuncture-analgesia is used for pain management during various surgical procedures. Over the past 40 years this approach has been introduced in many countries and has been particularly helpful in the investigation and treatment of patients who are unable to tolerate conventional analgesia. We report here the case of a woman with a 17-year history of myalgic encephalitis who underwent a stereotactic core biopsy of the breast under acupuncture-analgesia. A planning session was needed to assess the patient’s existing condition and her response to acupuncture. During this session, a range of frequencies for electrical stimulation of the acupuncture needles using electro-acupuncture apparatus was determined. We describe the combined acupuncture and biopsy procedures and the patient’s impressions and outcomes are recorded.
doi:10.1259/bjr/20216505
PMCID: PMC3473753  PMID: 20846978
6.  Clinical Characteristics and Biomarkers of Breast Cancer Associated with Choline Concentration Measured by 1H MR Spectroscopy 
NMR in biomedicine  2010;24(3):316-324.
This study was to investigate the association between tCho and the clinical characteristics and biomarker status of breast cancer. Sixty-two patients with breast cancer which was 1.5 cm or larger in size on MR images were studied. The tCho concentration was correlated with the MR imaging features, the contrast enhancement kinetics, clinical variables, and biomarkers. Pair-wise two-tailed Spearman’s non-parametric test was used for the statistical analysis. The tCho was higher in high grade than moderate/low grade tumor (p=0.04) and in tumors with higher Ktrans and kep (p<0.001 for both). The association of tCho with age (p=0.05) and triple negative biomarker (p=0.09) approached significance. tCho was not detected in 17 patients, including 15 invasive ductal cancer and 2 infiltrating lobular cancer. Fifteen of the 17 patients had moderate to low grade cancers, and 11 had HER-2 negative cancer, suggesting these two factors might lead to false negative choline. Higher tCho in high grade tumors and tumors with higher Ktrans and kep indicates choline is associated with cell proliferation and tumor angiogenesis. Higher choline level in younger women may be due to their more aggressive tumor type. The results presented here may aid in better interpretation of 1H MRS for diagnosis of breast lesions.
doi:10.1002/nbm.1595
PMCID: PMC3075960  PMID: 20862660
11.  Utility of PDL progenitors for in vivo tissue regeneration: a report of 3 cases 
Oral diseases  2010;16(1):20-28.
Objective
Periodontal disease is an inflammatory disorder with widespread morbidities involving both oral and systemic health. The primary goal of periodontal treatment is the regeneration of the lost or diseased periodontium. In this study, we retrospectively examined feasibility and safety of reconstructing the periodontal intrabony defects with autologous periodontal ligament progenitor (PDLP) implantation in three patients.
Materials and Methods
In this retrospective pilot study, we treated 16 teeth with at least one deep intrabony defect of probing depth (PD) ≥ 6 mm with PDLP transplantation and evaluated clinical outcome measures in terms of probing depth, gingival recession and attachment gain for a duration of 32–72 months. Furthermore, we compare PDLPs with standard PDL stem cells (PDLSCs) and confirmed that PDLPs possessed progenitor characters.
Results
Clinical examination indicated that transplantation of PDLPs may provide therapeutic benefit for the periodontal defects. All treated patients showed no adverse effects during the entire course of follow up. We also found that PDLPs were analogous to PDLSCs in terms of high proliferation, expression of mesenchymal surface molecules, multipotent differentiation, and in vivo tissue regain. However, PDLPs failed to express scleraxis, a marker of tendon, as seen in PDLSCs.
Conclusions
This study demonstrated clinical and experimental evidences supporting a potential efficacy and safety of utilizing autologous PDL cells in the treatment of human periodontitis.
PMCID: PMC2848819  PMID: 20355278
periodontal ligament progenitors; regeneration; periodontitis
13.  Quality of life after curative gastrectomy for gastric cancer in a randomised controlled trial 
British Journal of Cancer  2008;98(1):54-59.
Quality of life (QOL) was studied in gastric cancer patients treated on a randomised, controlled trial comparing D1 (level 1) with D3 (levels 1, 2 and 3) lymphadenectomy. A total of 221 patients were randomly assigned to D1 (n=110) and D3 (n=111) surgery. Quality-of-life assessments included functional outcomes (a 14-item survey about treatment-specific symptoms) and health perception (Spitzer QOL Index) was performed before and after surgery at disease-free status. Patients suffered from irrelative events such as loss of partners was excluded thereafter. Main analyses were done by intention-to-treat. Thus, 214 D1 (106/110=96.4%) and D3 (108/111=97.3%) R0 patients were assessed. Longitudinal analysis showed that functional outcomes decreased at 6 months after surgery and increased over time thereafter, while health perceptions increased over time in general. On the basis of linear mixed model analyses, patients having total gastrectomy, advanced cancer and hemipancreaticosplenectomy, but not complications had poorer QOL than those without. D1 and D3 patients showed no significant difference in QOL. The results suggest that changes of QOL were largely due to scope of gastric resection, disease status and distal pancreaticosplenectomy, rather than the extent of lymph node dissection. This indicates that nodal dissection can be performed for a potentially curable gastric cancer.
doi:10.1038/sj.bjc.6604097
PMCID: PMC2359701  PMID: 18182977
quality of life; nodal dissection; gastric cancer; trial
17.  Embryonic Expression and Extracellular Secretion of Xenopus Slit 
Neuroscience  2000;96(1):231-236.
The slit genes have recently been found to encode proteins with a conserved chemorepulsive activity for axons in invertebrates and vertebrates. We have determined the expression pattern of a slit gene in Xenopus embryos. In the neural tube, slit is expressed at the ventral and dorsal midlines, and the motor neurons. slit is also expressed in a changing pattern in the retina. The full-length Xenopus Slit protein is secreted extracellularly, whereas its receptor Roundabout can not be secreted. Using a myc-tagged secreted Slit protein, we confirmed the binding of Slit to Roundabout expressed on the cell surface.
These results confirm Slit–Roundabout interactions and the biochemical properties of Slit and Roundabout proteins, and further support the idea that Slit may guide axon projections in multiple regions of the embryo.
PMCID: PMC2072876  PMID: 10683427
Slit; Roundabout; olfactory bulb; axon guidance; chemorepulsion
18.  The proto-oncogene c-ets is preferentially expressed in lymphoid cells. 
Molecular and Cellular Biology  1985;5(11):2993-3000.
The transforming sequences of the avian acute leukemia virus, E26, contain two distinct oncogenes, v-mybE and v-ets, fused together. By using a probe containing v-ets sequences, polyadenylated transcripts of the c-ets proto-oncogene were detected in avian tissues; they included a major 7.0-kilobase and a minor 2.0-kilobase species. These c-ets mRNAs were detected at high levels only in lymphoid organs and in avian T and B lymphoid cell lines. A similar pattern of c-ets transcription was observed in human hematopoietic cell lines, with transcripts detected in lymphoid B and T cells but not in erythroid or myeloid cells. The E26 oncogene was inserted into an inducible expression vector, and a 90-kilodalton protein (bp90) was produced in bacteria. Rabbit antisera raised to purified bp90 precipitated P135gag-mybE-ets, the v-mybE-ets polyprotein expressed in E26-transformed cells, and also reacted with p50v-mybA, the transforming protein of the avian myeloblastosis virus. Antiserum to bp90 was absorbed with a bacterially synthesized v-mybA protein to remove anti-myb activity. The absorbed anti-bp90 serum retained the ability to immunoprecipitate P135gag-mybE-ets from E26-transformed cells and specifically reacted with a 56-kilodalton polypeptide (p56) detected in chicken lymphoid organs and in T and B lymphocytes of both avian and human origin. The data suggest that p56 is a translational product of the c-ets proto-oncogene and imply that p56 may be involved in regulating the growth of lymphoid cells.
Images
PMCID: PMC369111  PMID: 3018492
19.  In vitro translation of avian myeloblastosis virus RNA. 
Journal of Virology  1981;40(1):107-117.
Avian myeloblastosis virus (AMV)-infected cells contain two viral mRNA's, a genome-sized 34S (7.5-kilobase) mRNA and a 21S (2.5-kilobase) subgenomic mRNA, which contains the AMV-specific sequences (myb sequences). We found that AMV virions packaged both the 7.5-kilobase full-length genomic RNA and the 2.5-kilobase subgenomic RNA. In vitro translation of AMV virion RNA sized by sucrose density gradient centrifugation yielded 76,000-, 56,000-, 48,500-, 47,000-, and 32,000-dalton products. The 76,000-dalton protein was coded for by RNA throughout the gradient, but the peak of activity was at 34S to 35S. The 56,000-, and 48,500-, and 32,000-dalton proteins were encoded in a 21S RNA, and 47,000-dalton protein was encoded in an RNA of approximately 24S. The 76,000-dalton protein was identified as Pr76gag, based upon immunoprecipitation with specific antiserum and the presence of the 19* dipeptide. 7-Methylguanosine triphosphate inhibited the syntheses of Pr76gag and the 56,000-, 48,500-, and 32,000-dalton proteins, but not the synthesis of the 47,000-dalton protein. The 56,000-, 48,500-, 47,000-, and 32,000-dalton proteins were not immunoprecipitated by anti-gag, anti-reverse transcriptase, or anti-gp85 antiserum. Two-dimensional peptide maps of the 56,000- and 48,500-dalton proteins indicated that they were unique. In vitro translational products of myeloblastosis-associated virus 1 were also analyzed to aid in the identification of the AMV myb gene product(s); the translational products analyzed included Pr76gag, p60env, and a 56,000-dalton polypeptide which apparently was not identical to the 56,000-dalton AMV translational product, as determined by two-dimensional peptide mapping. Our data indicated that one of these proteins (56,000, 48,500, or 32,000 daltons) may represent the product of the AMV myb gene and, therefore, the putative transforming protein(s) of AMV.
Images
PMCID: PMC256600  PMID: 6270366
20.  Expression of endogenous avian myeloblastosis virus information in different chicken cells. 
Journal of Virology  1980;36(1):162-170.
Uninfected chicken cells were found to contain endogenous avian myeloblastosis virus (AMV)-specific information. Different tissues from chicken embryos and chickens expressed different amounts of the AMV-specific information. The endogenous AMV-related RNA was most abundant in bone marrow cells, which contained about 20 copies per cell. About 5 to 10 copies of AMV endogenous RNA per cell were found in embryonic yolk sac cells and bursa cells. The spleen, muscle, liver, and kidney cells of chickens and the fibroblasts of chicken embryos contained about two copies per cell. The amounts of AMV endogenous RNA in bone marrow, yolk sac, and bursa varied with age. From 19-day-old embryos to 2-week-old chickens, the bone marrow contained 20 copies of AMV RNA per cell. Bone marrow cells from 2-year-old chickens contained five copies per cell. Yolk sac cells of 10-day-old embryos and 1-day-old chickens were found to contain two copies per cell, whereas in 15- to 17-day-old embryos, these cells contained 5 to 10 copies. These results indicate that the level of endogenous AMV expression correlates with the development of granulopoiesis of the chicken hemopoietic system. The results of experiments on the thermostability of RNA-DNA hybrids indicated that the endogenous AMV RNA is closely related to viral AMV RNA. The expression of endogenous AMV information is independent of the activity of the chick helper factor. This endogenous AMV information is expressed as 20 to 21S RNA in both bone marrow and yolk sac cells.
PMCID: PMC353627  PMID: 6255203
21.  Avian Tumor Virus Proteins and RNA in Uninfected Chicken Embryo Cells 
Journal of Virology  1974;14(6):1419-1429.
The content of proteins P19 and P15 (mol wt 19,000 and 15,000, respectively) of avian leukovirus in various types of uninfected chicken embryos has been determined by radioimmunoassay. All chicken embryos examined, including embryos which have thus far been classified as group specific (gs) antigen negative by complement fixation tests, contained these viral proteins as well as P27 as previously reported. The embryos known as “gs antigen-positive” type contained about five times as much of these viral proteins as did the “gs antigen-negative” type. The ratio of the three viral proteins was similar for all types of embryos, suggesting that the genes for these proteins are coordinately controlled. In contrast to the relatively high levels of viral internal proteins in gs antigen-negative cells, the amounts of virus-specific RNA detectable by molecular hybridization were extremely low. The levels of helper activity, which presumably reflect the level of viral envelope glycoprotein, were also generally low or undetectable in these cells. Thus, the expression of the gene for envelope glycoprotein does not appear to be controlled coordinately with the genes for viral internal proteins.
PMCID: PMC355670  PMID: 4372405
22.  Detection of a Protein of Avian Leukoviruses in Uninfected Chick Cells by Radioimmunoassay 
Journal of Virology  1974;13(2):340-346.
A radioimmunoassay (RIA) has been used to measure the quantity of protein P27 (mol wt 27,000; group specific-1 [gs-1]) of avian leukoviruses in different types of chicken embryos and tissues of adult chickens. The RIA used was 200- to 300-fold more sensitive than the complement fixation test and was able to detect as little as 0.3 ng of P27. Among six embryos tested, which are negative for gs antigen by the complement fixation test, P27 was undetectable in three embryos, but another three contained about 5 ng of P27 per mg of cell protein by RIA. The amount of P27 in gs antigen-positive cells ranged from 22 to 57 ng per mg of cell protein. P27 was found in liver, lung, ovary, feather pulp, and spleen from adult gs antigen-positive chickens. This protein was undetectable in various tissues from gs antigen-negative chickens.
PMCID: PMC355302  PMID: 16789140
23.  Overexpressed hPTTG1 promotes breast cancer cell invasion and metastasis by regulating GEF-H1/RhoA signalling 
Oncogene  2011;31(25):3086-3097.
Human pituitary tumour-transforming gene 1 (hPTTG1) is an oncogenic transcription factor that is overexpressed in many tumour types, especially tumours with metastatic abilities. However, how hPTTG1 overexpression drives metastasis is not yet clear. As a transcription factor, hPTTG1 may promote metastasis by activating target genes that are involved in the metastatic process. Here, we showed that Rho guanine nucleotide exchange factor-H1 (GEF-H1) was transcriptionally activated by hPTTG1, thereby promoting breast cancer metastasis. Luciferase reporter analyses and chromatin immunoprecipitation (ChIP) assays showed that hPTTG1 directly bound and activated the GEF-H1 gene promoter. In this study, RNA interference-mediated knockdown of hPTTG1 in highly metastatic breast tumour cells decreased GEF-H1 expression and RhoA activation, thereby reducing cell motility and invasion, and interfering with cytoskeletal remodelling in vitro, and impairing the tumour metastasis in vivo. The restoration of GEF-H1 expression in hPTTG1-knockdown cells rescued the hPTTG1-knockdown effects on cytoskeletal changes in vitro and tumour metastasis in vivo. Conversely, ectopic expression of hPTTG1 in non-metastatic breast tumour cells induced cytoskeletal rearrangements, and allowed these cells to metastasise in a mouse model by orthotopic implantation. In human tumour samples, hPTTG1 expression was also correlated to GEF-H1 expression in aggressive breast carcinoma. Altogether, these findings definitively establish a role for hPTTG1 in activating the GEF-H1/RhoA pathway as a newly identified mechanism in breast cancer metastasis.
doi:10.1038/onc.2011.476
PMCID: PMC3381367  PMID: 22002306
hPTTG1; GEF-H1; RhoA; tumour metastasis; cytoskeleton regulation
25.  Trace metal mobilization in soil by bacterial polymers. 
Environmental Health Perspectives  1995;103(Suppl 1):53-58.
Enhanced transport of trace metal in porous media can occur in the presence of a ligand or "carrier" that has a high affinity for binding the pollutant, is dispersed and mobile in the soil environment, is recalcitrant with respect to microbial degradation, and is acceptable to the public. These aspects of the facilitated transport to trace metals are discussed with respect to a naturally occurring carrier: extracellular polymers of bacterial origin. The literature is reviewed regarding the production and composition of bacterial extracellular polymers, the processes relevant to the facilitated transport of trace metals in soil by bacterial polymers, and potential for transformation of polymers in soils by microbial degradation. Model calculations of contaminant retardation are presented for the case of polymer-mediated transport of cadmium in a sandy aquifer material. The available information suggests that extracellular polymers can bind metal ions and are mobile in the soil environment. Extracellular polymers also appear to be relatively slowly degraded by soil microorganisms. These properties and the supporting model calculations indicate that extracellular polymers of bacterial origin merit consideration as agents that may be applied to contaminated soils to enhance trace metal mobility.
PMCID: PMC1519318  PMID: 7621800

Results 1-25 (33)