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Find video protocols related to scientific articles indexed in Pubmed.
Osteoporosis increases subsequent risk of gallstone: a nationwide population-based cohort study in Taiwan.
BMC Gastroenterol
PUBLISHED: 11-18-2014
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BackgroundOsteopontin (OPN) is a pro-inflammatory cytokine which is expressed in various tissues. It participates in the bone remodeling process and stimulates bone resorption by osteoclasts. It is also a core protein of cholesterol gallstones. We hypothesized osteoporotic patients might have higher risk in developing gallstones and conducted a population-based study to examine the risk of developing gallstone in osteoporotic patients in Taiwan.MethodsA total of 1,638 patients diagnosed with osteoporosis between 2003 and 2005 were identified in the National Health Insurance Research Database. A comparison cohort without osteoporosis (n =6,552) was randomly matched to each osteoporosis patient at a ratio of 4: 1 based on age and sex. A Cox proportional-hazards regression analysis was performed to evaluate the 5-year gallstone-free survival rates for the 2 cohorts.ResultsDuring the 5-year follow-up period, 114 and 311 cases of gallstone occurred in the osteoporosis and comparison cohorts, respectively. After adjusting for the confounders, the Cox regression analysis of the risk of gallstone in the osteoporosis and comparison cohorts yielded a hazard ratio of 1.35 (95% confidence interval: 1.07 - 1.69; p < 0 .01).ConclusionPatients with osteoporosis in Taiwan have a higher risk of developing gallstone than the general population.
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Dynamic particle tracking via temporal focusing multiphoton microscopy with astigmatism imaging.
Opt Express
PUBLISHED: 11-18-2014
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A three-dimensional (3D) single fluorescent particle tracking strategy based on temporal focusing multiphoton excitation microscopy (TFMPEM) combined with astigmatism imaging is proposed for delivering nanoscale-level axial information that reveals 3D trajectories of single fluorospheres in the axially-resolved multiphoton excitation volume without z-axis scanning. Whereas other scanning spatial focusing multiphoton excitation schemes induce optical trapping interference, temporal focusing multiphoton excitation produces widefield illumination with minimum optical trapping force on the fluorospheres. Currently, the lateral and axial positioning resolutions of the dynamic particle tracking approach are about 14 nm and 21 nm in standard deviation, respectively. Furthermore, the motion behavior and diffusion coefficients of fluorospheres in glycerol solutions with different concentrations are dynamically measured at a frame rate up to 100 Hz. This TFMPEM with astigmatism imaging holds great promise for exploring dynamic molecular behavior deep inside biotissues via its superior penetration, reduced trapping effect, fast frame rate, and nanoscale-level positioning.
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Chemoselective per-O-trimethylsilylation and homogeneous N-functionalisation of amino sugars.
Chem. Commun. (Camb.)
PUBLISHED: 11-11-2014
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A highly efficient CH3CN-promoted hexamethyldisilazane per-O-trimethylsilylation of amino sugars was developed. Its applications in homogenous N-functionalisation and a concise synthesis of glucosamine 6-phosphate are described.
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Measurement of extreme hyperfine fields in two-coordinate high-spin fe(2+) complexes by mössbauer spectroscopy: essentially free-ion magnetism in the solid state.
Inorg Chem
PUBLISHED: 11-04-2014
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Mössbauer studies of three two-coordinate linear high-spin Fe(2+) compounds, namely, Fe{N(SiMe3)(Dipp)}2 (1) (Dipp = C6H3-2,6-(i)Pr2), Fe(OAr')2 (2) [Ar' = C6H3-2,6-(C6H3-2,6-(i)Pr2)2], and Fe{C(SiMe3)3}2 (3), are presented. The complexes were characterized by zero- and applied-field Mössbauer spectroscopy (1-3), as well as zero- and applied-field heat-capacity measurements (3). As 1-3 are rigorously linear, the distortion(s) that might normally be expected in view of the Jahn-Teller theorem need not necessarily apply. We find that the resulting very large unquenched orbital angular momentum leads to what we believe to be the largest observed internal magnetic field to date in a high-spin iron(II) compound, specifically +162 T in 1. The latter field is strongly polarized along the directions of the external field for both longitudinal and transverse field applications. For the longitudinal case, the applied field increases the overall hyperfine splitting consistent with a dominant orbital contribution to the effective internal field. By contrast, 2 has an internal field that is not as strongly polarized along a longitudinally applied field and is smaller in magnitude at ca. 116 T. Complex 3 behaves similarly to complex 1. They are sufficiently self-dilute (e.g., Fe···Fe distances of ca. 9-10 Å) to exhibit varying degrees of slow paramagnetic relaxation in zero field for the neat solid form. In the absence of EPR signals for 1-3, we show that heat-capacity measurements for one of the complexes (3) establish a geff value near 12, in agreement with the principal component of the ligand electric field gradient being coincident with the z axis.
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Novel KCNJ5 Mutations in Sporadic Aldosterone-producing Adenoma Reduce Kir3.4 Membrane Abundance.
J. Clin. Endocrinol. Metab.
PUBLISHED: 10-28-2014
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Context: Aldosterone-producing adenoma (APA) has been linked to mutations in KCNJ5 gene encoding inward-rectifying potassium (K(+)) Kir3.4 channel. These mutations abolish the K(+) selectivity of Kir3.4 and, consequently, cause sodium (Na(+)) leak, depolarized membrane potential, and non-suppressible aldosterone secretion. Objective: To investigate KCNJ5 mutations in patients with sporadic APA and the role of endogenous Kir3.4 in human adrenocortical cells. Design: We screened the KCNJ5 gene from the adrenal adenomas of 69 Chinese patients with sporadic APA and functionally characterized novel Kir3.4 mutations. Results: Thirty-seven percent (26/69) of our APA patients carried heterozygous somatic mutations in KCNJ5 gene. Besides the most common G151R and L168R mutations, we identified a previously uncharacterized E145Q mutation and two novel mutations (R115W, E246G) in six patients. E145Q mutant conducted a barium-insensitive Na(+)-leak current. R115W and E246G mutants preserved barium-sensitive, K(+)-selective and G??-activable Kir3.4 currents, which were ?30% and ?15% of wild-type current, respectively. Biotinylation assays revealed markedly reduced membrane abundance of R115W and E246G mutants. All Kir3.4 mutants exerted dominant-negative effects on wild-type channel. Kir3.4 protein expression in APAs with novel KCNJ5 mutation was significantly lower than those in APAs with wild type KCNJ5 or Na(+)-leak KCNJ5 mutations. Inhibition of endogenous Kir3.4 by tertiapin-Q significantly depolarized membrane potential and increased CYP11B2 expression in human adrenocortical cells. Conclusion: Besides Na(+)-leak mutations, novel KCNJ5 mutations causing a reduction of surface and total abundance of Kir3.4 are also associated with sporadic APA. Basal Kir3.4 current is important to maintaining normal resting membrane potential and suppressing aldosterone synthesis in human adrenocortical cells.
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Graphene oxide-based micropatterns via high-throughput multiphoton-induced reduction and ablation.
Opt Express
PUBLISHED: 10-17-2014
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In this study, a developed temporal focusing-based femtosecond laser system provides high-throughput multiphoton-induced reduction and ablation of graphene oxide (GO) films. Integrated with a digital micromirror device to locally control the laser pulse numbers, GO-based micropatterns can be quickly achieved instantly. Furthermore, the degree of reduction and ablation can be precisely adjusted via controlling the laser wavelength, power, and pulse number. Compared to point-by-point scanning laser direct writing, this approach offers a high-throughput and multiple-function approach to accomplish a large area of micro-scale patterns on GO films. The high-throughput micropatterning of GO via the temporal focusing-based femtosecond laser system fulfills the requirement of mass production for GO-based applications in microelectronic devices.
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6-Dehydrogingerdione restrains lipopolysaccharide-induced inflammatory responses in RAW 264.7 macrophages.
J. Agric. Food Chem.
PUBLISHED: 09-09-2014
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6-Dehydrogingerdione (6-DG), one important component of ginger, has been reported to possess some medical effects, such as antitumor and antiatherosclerosis. Herein, the anti-inflammatory effects of 6-DG against lipopolysaccharides (LPS) induced pro-inflammation mediators in RAW 264.7 cells were investigated. Results show that 6-DG significantly attenuated inducible nitric oxide synthase (iNOS, NOS2), cyclooxygenase-2 (COX-2), interleukin-1? (IL-1?), interleukin 6 (IL-6), and tumor necrosis factor-? (TNF-?) in the LPS-mediated murine macrophages (RAW 264.7 cells). 6-DG inhibited LPS-induced phosphorylation of both p38 and nuclear factor of ? light polypeptide gene enhancer in B-cells inhibitor-? (I?B?), which further prevented p-p65 nuclear factor-?B (NF-?B-p65) translocation to the nucleus. Moreover, 6-DG increased the ratio of phosphorylated signal transducers and activators of transcription 1 (p-STAT1)/p-STAT3 and down-regulated the gene expression of IL-1?, IL-6, and IL-10.
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Evidence of sleep-facilitating effect on formation of novel semantic associations: An event-related potential (ERP) study.
Neurobiol Learn Mem
PUBLISHED: 08-27-2014
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Paired-associates learning of unrelated words can reflect the formation of a new association in the semantic network. Research results on the facilitating effect of sleep on unrelated word-pair associates learning remain contradictory. The behavioral measures used in previous studies may not have been sensitive enough to reflect the process of new word association during sleep. The present study used the N400 component of event-related potential (ERP) to further assess the facilitating effect of sleep on the formation of new semantic associations. Thirty subjects were randomly assigned to either the Sleep group or the Wakefulness group. After paired-associates learning and pre-test, they underwent nocturnal sleep and sleep deprivation, respectively. A post-test was conducted after the subjects had one night of recovery sleep. ERPs were recorded during both test phases. Behavioral data showed significant differences in improvements in recognition and decreases in reaction time from pre-test to post-test between the Sleep and Wakefulness groups. The N400 peak amplitude attenuated significantly after sleep, but not after wakefulness. These results suggest that sleep has a facilitating effect on the formation of novel associations. Unexpectedly, slow wave sleep was negatively correlated with improvement in recognition during the post-test but was positively correlated with the number of word-pairs acquired during the learning phase. This may the result of a ceiling effect limiting the improvement achieved in subjects who learned better during the learning phase.
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Fetal magnetic resonance imaging of normal spinal cord: evaluating cord visualization and conus medullaris position by T2-weighted sequences.
Biomed J
PUBLISHED: 08-14-2014
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Prenatal magnetic resonance (MR) imaging demonstration of the normal spinal cord and the conus medullaris location has not been well studied. We compared balanced fast field echo (bFFE) with single-shot turbo spin-echo (SSh-TSE) MR sequences for visualizing the normal spinal cord and position of conus medullaris in fetuses.
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Synthesis, structure, and magnetic and electrochemical properties of quasi-linear and linear iron(I), cobalt(I), and nickel(I) amido complexes.
Inorg Chem
PUBLISHED: 08-13-2014
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Three potassium crown ether salts, [K(Et2O)2(18-crown-6)][Fe{N(SiMe3)Dipp}2] (1a; Dipp = C6H3-2,6-Pr(i)2), [K(18-crown-6)][Fe{N(SiMe3)Dipp}2]·0.5PhMe (1b), and [K(18-crown-6)][M{N(SiMe3)Dipp}2] (M = Co, 2; M = Ni, 3), of the two-coordinate linear or near-linear bis-amido monoanions [M{N(SiMe3)Dipp}2](-) (M = Fe, Co, Ni) were synthesized by one-electron reduction of the neutral precursors M{N(SiMe3)Dipp}2 with KC8 in the presence of 18-crown-6. They were characterized by X-ray crystallography, UV-vis spectroscopy, cyclic voltammetry, and magnetic measurements. The anions feature lengthened M-N bonds in comparison with their neutral precursors, with slightly bent coordination (N-Fe-N = ca. 172°) for the iron(I) complex, but linear coordination for the cobalt(I) and nickel(I) complexes. Fits of the temperature dependence of ?MT of 1 and 2 reveal that the iron(I) and cobalt(I) complexes have large negative D zero-field splittings and a substantial orbital contribution to their magnetic moments with L = 2, whereas the nickel(I) complex has at most a small orbital contribution to its magnetic moment. The magnetic results have been used to propose an ordering of the 3d orbitals in each of the complexes.
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Management trends in stage I testicular seminoma: Impact of race, insurance status, and treatment facility.
Cancer
PUBLISHED: 07-18-2014
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The management of stage I testicular seminoma is evolving rapidly. This study examined modern trends in the management of stage I testicular seminoma and the effects of sociodemographic factors on therapy choice.
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Nonlinear structured-illumination enhanced temporal focusing multiphoton excitation microscopy with a digital micromirror device.
Biomed Opt Express
PUBLISHED: 07-08-2014
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In this study, the light diffraction of temporal focusing multiphoton excitation microscopy (TFMPEM) and the excitation patterning of nonlinear structured-illumination microscopy (NSIM) can be simultaneously and accurately implemented via a single high-resolution digital micromirror device. The lateral and axial spatial resolutions of the TFMPEM are remarkably improved through the second-order NSIM and projected structured light, respectively. The experimental results demonstrate that the lateral and axial resolutions are enhanced from 397 nm to 168 nm (2.4-fold) and from 2.33 ?m to 1.22 ?m (1.9-fold), respectively, in full width at the half maximum. Furthermore, a three-dimensionally rendered image of a cytoskeleton cell featuring ~25 nm microtubules is improved, with other microtubules at a distance near the lateral resolution of 168 nm also able to be distinguished.
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Employing injection-locked FP LDs to set up a hybrid CATV/MW/MMW WDM light wave transmission system.
Opt Lett
PUBLISHED: 07-01-2014
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A hybrid cable television (CATV)/microwave (MW)/millimeter-wave (MMW) wavelength-division-multiplexing (WDM) light wave transmission system based on injection-locked Fabry-Perot laser diodes (FP LDs) is proposed and demonstrated. Different from conventional hybrid WDM light wave transmission systems, which need wavelength-selected distributed feedback laser diodes to support various services, the proposed systems employ injection-locked FP LDs to provide multiple applications. Over a 40 km single-mode fiber transport, impressive performances of carrier-to-noise ratio/composite second-order/composite triple-beat/bit error rate are obtained for 550 MHz CATV/20 GHz MW/40 GHz MMW/60 GHz MMW signal transmissions. Such a hybrid WDM light wave transmission system would be attractive for fiber links to provide broadband integrated services.
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Bidirectional hybrid PM-based RoF and VCSEL-based VLLC system.
Opt Express
PUBLISHED: 07-01-2014
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A bidirectional hybrid phase modulation (PM)-based radio-over-fiber (RoF) and vertical cavity surface emitting laser (VCSEL)-based visible laser light communication (VLLC) systems employing injection-locked VCSEL-based PM-to-intensity modulation (IM) converters and optical interleavers (ILs) is proposed and demonstrated. To be the first one of using injection-locked VCSEL-based PM-to-IM converters and optical ILs in such bidirectional hybrid RoF and VLLC systems, the downstream light is successfully phase-remodulated with RoF signal for up-link transmission. Through a serious investigation in systems, bit error rate (BER) and eye diagram perform brilliantly over a 40-km single-mode fiber (SMF) transport and a 12-m free-space transmission. Such a bidirectional hybrid RoF and VLLC system would be very attractive for the integration of fiber backbone and in-door networks to provide broadband integrated services, including Internet and telecommunication services.
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Protective effect of anthocyanidins against sodium dithionite-induced hypoxia injury in C6 glial cells.
J. Agric. Food Chem.
PUBLISHED: 06-04-2014
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The present study investigated the neuroprotective effect of anthocyanidins, including cyanidin, delphinidin, malvidin, pelargonidin, and peonidin, against hypoxia in C6 glial cells. The cells were first incubated with a medium containing anthocynidin in normoxia condition and then with a medium containing sodium dithionite (Na2S2O4) in an anaerobic incubator for the hypoxia treatment. Methylthiazole tetrazolium test and evaluation of antioxidant enzyme activities and glutathione concentration were performed on the treated cells. At least 74% of the C6 cells preincubated with 25 mg/L of any of the five anthocyanidins in serum-free Dulbecco's modified Eagle's medium at 37 °C for 24 h survived the hypoxia treatment as compared with a survival rate between 47 and 59% for the control that was preincubated without an anthocyanidin. The cells preincubated with any of the five anthocyanidins showed higher catalase activity and glutathione concentration after the hypoxia treatment as compared with the corresponding samples without the preincubation with anthocyanidin. The cells preincubated with malvidin, pelargonidin, or peonidin also showed higher superoxide dismutase activities. The results of this study justify further research for the development of anthocyanidins into neuroprotective food ingredients against hypoxia injury.
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Cirrhosis as a risk factor for tuberculosis infection--a nationwide longitudinal study in Taiwan.
Am. J. Epidemiol.
PUBLISHED: 05-14-2014
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Tuberculosis (TB) and cirrhosis of the liver are both endemic in many regions of the world. However, the risk of TB in cirrhotic patients has rarely been investigated. A nationwide cohort study was conducted to elucidate and characterize the association between cirrhosis and TB in Taiwan. The study included 41,076 cirrhotic patients and 204,244 noncirrhotic controls from 1998 through 2007. Cirrhotic and noncirrhotic subjects were matched 1:5 on age and sex. A total of 957 of 41,076 (2.32%) cirrhotic patients developed TB, yielding a rate that was significantly higher than that of the 955 of 204,244 (0.46%) noncirrhotic patients (P < 0.001). In a Cox regression model adjusted for age, sex, and underlying medical disorders, a significantly higher active TB rate was maintained for cirrhotic patients compared with their noncirrhotic counterparts (adjusted hazard ratio = 3.55, 95% confidence interval (CI): 3.08, 4.09; P < 0.001). Alcoholism and hepatitis C infection were associated with significantly higher TB risk with adjust hazard ratios of 2.18 (95% CI: 1.86, 4.09; P < 0.001) and 1.18 (95% CI: 1.02, 1.30; P < 0.001), respectively. Cirrhotic patients have a greater risk of TB than noncirrhotic patients, particularly those with alcoholism and hepatitis C infection.
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Augmented miR-150 expression associated with depressed SOCS1 expression involved in dengue haemorrhagic fever.
J. Infect.
PUBLISHED: 05-09-2014
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Suppressors of cytokine signalling (SOCS) proteins regulate cytokine responses and control immune balance. The objective of our study was to determine whether the expression of SOCS1 and its potential regulatory microRNAs (miRNAs) in leukocytes is correlated to the development of dengue haemorrhagic fever (DHF).
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A full-duplex lightwave transmission system with an innovative VCSEL-based PM-to-IM converter.
Opt Express
PUBLISHED: 05-03-2014
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A full-duplex lightwave transmission system employing innovative VCSEL-based PM-to-IM converters to deliver intensity-modulated CATV/phase-modulated RoF/intensity-remodulated RoF signals over two 40-km SMFs links is proposed and demonstrated. To be the first one of employing VCSEL-based PM-to-IM converters in full-duplex lightwave transmission systems, the downstream light is successfully intensity-remodulated with RoF signal for up-link transmission. Good performances of CNR/CSO/CTB are achieved for downstream CATV signal transmission, and low BER values are obtained for both downstream and upstream RoF signals transmissions. Our proposed systems present brilliant performances in delivering hybrid CATV and RoF signals. Such a full-duplex lightwave transmission system would be very attractive for fiber trunk applications to provide broadband integrated services.
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Association between serious psychological distress and health care use and expenditures by cancer history.
Cancer
PUBLISHED: 04-21-2014
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Serious psychological distress (SPD) is associated with adverse health outcomes such as poor quality of life and shorter survival in cancer survivors, but to the authors' knowledge, the relationship between SPD and health care use and medical expenditures is not clear.
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Association of race/ethnicity, socioeconomic status, and breast cancer subtypes in the National Cancer Data Base (2010-2011).
Breast Cancer Res. Treat.
PUBLISHED: 04-17-2014
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To estimate the odds of breast cancer subtypes in minority populations versus non-Hispanic (NH) whites stratified by socioeconomic status (SES) [a composite of individual-level SES (insurance status) and area-level SES (median household income quartile from 2000 U.S. Census data)] using a large nationwide cancer database. We used the National Cancer Data Base to identify breast cancer cases diagnosed in 2010 and 2011, the only 2 years since U.S. cancer registries uniformly began collecting HER2 results. Breast cancer cases were classified into five subtypes based on hormone receptor (HR) and HER2 status: HR+/HER2-, HR+/HER2+, HR-/HER2+ (HER2-overexpressing), HR-/HER2- (TN), and unknown. A polytomous logistic regression was used to estimate odds ratios (ORs) comparing the odds of non-HR+/HER2-subtypes to HR+/HER2- for racial/ethnic groups controlling for and stratifying by SES, using a composite of insurance status and area-level income. Compared with NH whites, NH blacks and Hispanics were 84 % (OR = 1.84; 95 % CI 1.77-1.92) and 17 % (OR = 1.17; 95 % CI 1.11-1.24) more likely to have TN subtype versus HR+/HER2-, respectively. Asian/Pacific Islanders (API) had 1.45 times greater odds of being diagnosed with HER2-overexpressing subtype versus HR+/HER2- compared with NH whites (OR = 1.45; 95 % CI 1.31-1.61). We found similar ORs for race in high and low strata of SES. In a large nationwide hospital-based dataset, we found higher odds of having TN breast cancer in black women and of HER2-overexpressing in API compared with white women in every level of SES.
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Cancer treatment and survivorship statistics, 2014.
CA Cancer J Clin
PUBLISHED: 04-14-2014
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The number of cancer survivors continues to increase due to the aging and growth of the population and improvements in early detection and treatment. In order for the public health community to better serve these survivors, the American Cancer Society and the National Cancer Institute collaborated to estimate the number of current and future cancer survivors using data from the Surveillance, Epidemiology, and End Results (SEER) program registries. In addition, current treatment patterns for the most common cancer types are described based on information in the National Cancer Data Base and the SEER and SEER-Medicare linked databases; treatment-related side effects are also briefly described. Nearly 14.5 million Americans with a history of cancer were alive on January 1, 2014; by January 1, 2024, that number will increase to nearly 19 million. The 3 most common prevalent cancers among males are prostate cancer (43%), colorectal cancer (9%), and melanoma (8%), and those among females are cancers of the breast (41%), uterine corpus (8%), and colon and rectum (8%). The age distribution of survivors varies substantially by cancer type. For example, the majority of prostate cancer survivors (62%) are aged 70 years or older, whereas less than one-third (32%) of melanoma survivors are in this older age group. It is important for clinicians to understand the unique medical and psychosocial needs of cancer survivors and to proactively assess and manage these issues. There are a growing number of resources that can assist patients, caregivers, and health care providers in navigating the various phases of cancer survivorship.
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Regulation of human endothelial progenitor cell maturation by polyurethane nanocomposites.
Biomaterials
PUBLISHED: 04-04-2014
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The mobilization and homing of endothelial progenitor cells (EPCs) are critical to the development of an antithrombotic cardiovascular prosthesis. Polyurethane (PU) with superior elasticity may provide a mechanical environment resembling that of the natural vascular tissues. The topographical cues of PU were maximized by making nanocomposites with a small amount of gold nanoparticles (AuNPs). The nanocomposites of PU-AuNPs ("PU-Au") with a favorable response of endothelial cells were previously established. In the current study, the effect of PU and PU-Au nanocomposites on the behavior of human peripheral blood EPCs was investigated in vitro and in vivo. It was found that PU-Au promoted EPCs to become differentiated endothelial cells in vitro, confirmed by the increased expressions of CD31 and VEGF-R2 surface markers. The increased maturation of EPCs was significantly more remarkable on PU-Au, probably through the stromal derived factor 1? (SDF-1?)/CXCR4 signaling pathway. In vivo experiments showed that EPCs seeded on PU-Au coated catheters effectively reduced thrombosis by differentiation into endothelial cells. Surface endothelialization with CD31 and CD34 expression as well as intimal formation with ?-SMA expression was significantly accelerated in the group receiving EPC-seeded PU-Au catheters. Moreover, the analysis of collagen deposition revealed a reduction of fibrosis in the group receiving EPC-seeded PU-Au catheters as compared to the other groups. These results suggest that EPCs engineered with a proper elastic substrate may provide unique endothelialization and antithrombogenic properties that benefit vascular tissue regeneration.
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Two-way lightwave subcarrier transmission system.
Opt Lett
PUBLISHED: 04-02-2014
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This Letter proposes and demonstrates a two-way lightwave subcarrier transmission system employing interleavers to deliver intensity-modulated CATV/phase-modulated RoF/intensity-remodulated 16-QAM-OFDM signals over two 20 km SMF links. To the best of our knowledge, it is the first time that interleavers have been employed in two-way lightwave subcarrier transmission systems. The downstream light is successfully intensity-remodulated with a 16-QAM-OFDM signal for uplink transmission. We obtained excellent performance from the CNR/CSO/CTB/BER for CATV/RoF/16-QAM-OFDM signal transmissions. The proposed systems offer impressive performance features to deliver hybrid CATV/RoF/16-QAM-OFDM signals.
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Magnetic-resonance imaging for kinetic analysis of permeability changes during focused ultrasound-induced blood-brain barrier opening and brain drug delivery.
J Control Release
PUBLISHED: 03-13-2014
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Focused ultrasound (FUS) with the presence of microbubbles has been shown to induce transient and local opening of the blood-brain barrier (BBB) for the delivery of therapeutic molecules which normally cannot penetrate into the brain. The success of FUS brain-drug delivery relies on its integration with in-vivo imaging to monitor kinetic change of therapeutic molecules into the brain. In this study, we developed a dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique for kinetic analysis of delivered molecules during FUS-BBB opening. Three kinetic parameters (Ktrans, Ve, Kep) were characterized dynamically to describe BBB-permeability at two FUS exposure conditions (0.4 or 0.8MPa) over 24h. Ktrans, defined as the influx volume transfer constant from plasma to EES, and Ve, the EES volume fraction, were both found to be pressure-dependent. Ktrans and Ve showed a peak increase of 0.0086-0.0131min(-1) (for 0.4-0.8MPa pressure), and 0.0431-0.0692, respectively, immediately after FUS exposure. Both parameters subsequently decreased exponentially as a function of time, with estimated half-lives of decay of 2.89-5.3 and 2.2-4.93h, respectively. The kinetics of Kep, defined as the efflux rate constant from the extracellular extravascular space (EES) to the plasma, were complementary to Ktrans, with an initial decrease from 0.2010 to 0.1901min(-1) followed by a significantly longer recovery time (half-life of 17.39-99.92h). Our observations strongly supported the existence of imbalanced and mismatched kinetics of influx (Ktrans) and efflux (Kep) between the plasma and EES, indicating the existence of directional permeability during FUS-BBB opening. We further showed that kinetic change determined by DCE-MRI correlated well with the concentration of Evans Blue (EB)-albumin (coefficient of 0.74-0.89). These findings suggest that MRI kinetic monitoring may serve as an alternative method for in-vivo monitoring of pharmacokinetics and pharmacodynamics (PK/PD) change of therapeutic agents during drug delivery to the brain, and provide useful information for future optimization of FUS-BBB opening.
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Optical free-space wavelength-division-multiplexing transport system.
Opt Lett
PUBLISHED: 02-25-2014
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An optical free-space wavelength-division-multiplexing (WDM) transport system employing vertical cavity surface emitting lasers and spatial light modulators with 16-quadrature amplitude modulation orthogonal frequency-division multiplexing modulating signals over a 17.5 m free-space link is proposed and demonstrated. With the help of a low-noise amplifier and data comparator, good bit error rate performance is obtained for each optical channel. Such an optical free-space WDM transport system would be attractive for providing services including data and telecommunication services.
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Association of reimbursement policy and urologists' characteristics with the use of medical androgen deprivation therapy for clinically localized prostate cancer.
Urol. Oncol.
PUBLISHED: 02-14-2014
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Physician characteristics and changes in drug reimbursement rates have been shown to influence practice patterns regardless of clinical guidelines, patient, clinical, or sociodemographic factors. We concurrently examined the association between urologists? characteristics and non-evidence-based use of primary medical androgen deprivation therapy (ADT) for clinically localized patients with prostate cancer, before and after the 2003 Medicare Modernization Act?s reductions in ADT reimbursement rates.
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Diagnosis date agreement between SEER and Medicare claims data: impact on treatment.
Med Care
PUBLISHED: 02-11-2014
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A prior assessment of concordance between the diagnosis month in SEER records and Medicare claims found reasonable agreement; however, no assessment of the impact of discordance on cancer treatment ascertainment was conducted.
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Contribution of bimodal hearing to lexical tone normalization in Mandarin-speaking cochlear implant users.
Hear. Res.
PUBLISHED: 02-09-2014
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Native Mandarin normal-hearing (NH) listeners can easily perceive lexical tones even under conditions of great voice pitch variations across speakers by using the pitch contrast between context and target stimuli. It is however unclear whether cochlear implant (CI) users with limited access to pitch cues can make similar use of context pitch cues for tone normalization. In this study, native Mandarin NH listeners and pre-lingually deafened unilaterally implanted CI users were asked to recognize a series of Mandarin tones varying from Tone 1 (high-flat) to Tone 2 (mid-rising) with or without a preceding sentence context. Most of the CI subjects used a hearing aid (HA) in the non-implanted ear (i.e., bimodal users) and were tested both with CI alone and CI + HA. In the test without context, typical S-shaped tone recognition functions were observed for most CI subjects and the function slopes and perceptual boundaries were similar with either CI alone or CI + HA. Compared to NH subjects, CI subjects were less sensitive to the pitch changes in target tones. In the test with context, NH subjects had more (resp. fewer) Tone-2 responses in a context with high (resp. low) fundamental frequencies, known as the contrastive context effect. For CI subjects, a similar contrastive context effect was found statistically significant for tone recognition with CI + HA but not with CI alone. The results suggest that the pitch cues from CIs may not be sufficient to consistently support the pitch contrast processing for tone normalization. The additional pitch cues from aided residual acoustic hearing can however provide CI users with a similar tone normalization capability as NH listeners.
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Association between Kawasaki disease and autism: a population-based study in Taiwan.
Int J Environ Res Public Health
PUBLISHED: 01-30-2014
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The association between Kawasaki disease and autism has rarely been studied in Asian populations. By using a nationwide Taiwanese population-based claims database, we tested the hypothesis that Kawasaki disease may increase the risk of autism in Taiwan.
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The CP110-interacting proteins Talpid3 and Cep290 play overlapping and distinct roles in cilia assembly.
J. Cell Biol.
PUBLISHED: 01-13-2014
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We have identified Talpid3/KIAA0586 as a component of a CP110-containing protein complex important for centrosome and cilia function. Talpid3 assembles a ring-like structure at the extreme distal end of centrioles. Ablation of Talpid3 resulted in an aberrant distribution of centriolar satellites involved in protein trafficking to centrosomes as well as cilia assembly defects, reminiscent of loss of Cep290, another CP110-associated protein. Talpid3 depletion also led to mislocalization of Rab8a, a small GTPase thought to be essential for ciliary vesicle formation. Expression of activated Rab8a suppressed cilia assembly defects provoked by Talpid3 depletion, suggesting that Talpid3 affects cilia formation through Rab8a recruitment and/or activation. Remarkably, ultrastructural analyses showed that Talpid3 is required for centriolar satellite dispersal, which precedes the formation of mature ciliary vesicles, a process requiring Cep290. These studies suggest that Talpid3 and Cep290 play overlapping and distinct roles in ciliary vesicle formation through regulation of centriolar satellite accretion and Rab8a.
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Intramolecular interactions of a phenyl/perfluorophenyl pair in the formation of supramolecular nanofibers and hydrogels.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-13-2014
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A new system for the incorporation of a phenyl/perfluorophenyl pair in the structure of a peptide hydrogelator was developed. The strategy is based on the idea that the integration of an end-capped perfluorophenyl group and a phenylalanine with a phenyl moiety in the side chain forms an intramolecular phenyl/perfluorophenyl pair, which can be used to promote the formation of the supramolecular nanofibers and hydrogels. This work illustrates the importance of structure-hydrogelation relationship and provides new insights into the design of self-assembly nanobiomaterials.
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Tract-based spatial statistics: application to mild cognitive impairment.
Biomed Res Int
PUBLISHED: 01-10-2014
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The primary objective of the current investigation was to characterize white matter integrity in different subtypes of mild cognitive impairment (MCI) using tract-based spatial statistics of diffusion tensor imaging.
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Involvement of the nuclear high mobility group B1 peptides released from injured hepatocytes in murine hepatic fibrogenesis.
Biochim. Biophys. Acta
PUBLISHED: 01-05-2014
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This study investigated the pro-fibrogenic role of high mobility group box 1 (HMGB1) peptides in liver fibrogenesis. An animal model of carbon tetrachloride (CCl4)-induced liver fibrosis was used to examine the serum HMGB1 levels and its intrahepatic distribution. The increased serum HMGB1 levels were positively correlated with elevation of transforming growth factor-?1 (TGF-?1) and collagen deposition during fibrogenesis. The cytoplasmic distribution of HMGB1 was noted in the parenchymal hepatocytes of fibrotic livers. In vitro studies confirmed that exposure to hydrogen peroxide and CCl4 induced an intracellular mobilization and extracellular release of nuclear HMGB1 peptides in clone-9 and primary hepatocytes, respectively. An uptake of exogenous HMGB1 by hepatic stellate cells (HSCs) T6 cells indicated a possible paracrine action of hepatocytes on HSCs. Moreover, HMGB1 dose-dependently stimulated HSC proliferation, up-regulated de novo synthesis of collagen type I and ?-smooth muscle actin (?-SMA), and triggered Smad2 phosphorylation and its nuclear translocation through a TGF-?1-independent mechanism. Blockade with neutralizing antibodies and gene silencing demonstrated the involvement of the receptor for advanced glycation end-products (RAGE), but not toll-like receptor 4, in cellular uptake of HMGB1 and the HMGB1-mediated Smad2 and ERK1/2 phosphorylation as well as ?-SMA up-regulation in HSC-T6 cells. Furthermore, anti-RAGE treatment significantly ameliorated CCl4-induced liver fibrosis. In conclusion, the nuclear HMGB1 peptides released from parenchymal hepatocytes during liver injuries may directly activate HSCs through stimulating HSC proliferation and transformation, eventually leading to the fibrotic changes of livers. Blockade of HMGB1/RAGE signaling cascade may constitute a therapeutic strategy for treatment of liver fibrosis.
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Clinical-pathologic stage discrepancy in bladder cancer patients treated with radical cystectomy: results from the national cancer data base.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 01-04-2014
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To examine the accuracy of clinical staging and its effects on outcome in bladder cancer (BC) patients treated with radical cystectomy (RC), using a large national database.
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The prognostic values of leukocyte Rho kinase activity in acute ischemic stroke.
Biomed Res Int
PUBLISHED: 01-03-2014
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It has been reported that leukocyte ROCK activity is elevated in patients after ischemic stroke, but it is unclear whether leukocyte ROCK activity is associated with clinical outcomes following acute stroke events. The objective of this study is to investigate if leukocyte ROCK activity can predict the outcomes in patients with acute ischemic stroke.
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Up-Regulation of Nerve Growth Factor in Cholestatic Livers and Its Hepatoprotective Role against Oxidative Stress.
PLoS ONE
PUBLISHED: 01-01-2014
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The role of nerve growth factor (NGF) in liver injury induced by bile duct ligation (BDL) remains elusive. This study aimed to investigate the relationship between inflammation and hepatic NGF expression, to explore the possible upstream molecules up-regulating NGF, and to determine whether NGF could protect hepatocytes from oxidative liver injury. Biochemical and molecular detection showed that NGF was up-regulated in cholestatic livers and plasma, and well correlated with systemic and hepatic inflammation. Conversely, systemic immunosuppression reduced serum NGF levels and resulted in higher mortality in BDL-treated mice. Immunohistochemistry showed that the up-regulated NGF was mainly localized in parenchymal hepatocytes. In vitro mechanistic study further demonstrated that TGF-?1 up-regulated NGF expression in clone-9 and primary rat hepatocytes. Exogenous NGF supplementation and endogenous NGF overexpression effectively protected hepatocytes against TGF-?1- and oxidative stress-induced cell death in vitro, along with reduced formation of oxidative adducted proteins modified by 4-HNE and 8-OHdG. TUNEL staining confirmed the involvement of anti-apoptosis in the NGF-exhibited hepatoprotection. Moreover, NGF potently induced Akt phosphorylation and increased Bcl-2 to Bax ratios, whereas these molecular alterations by NGF were only seen in the H2O2-, but not TGF-?1-treated hepatocytes. In conclusion, NGF exhibits anti-oxidative and hepatoprotective effects and is suggested to be therapeutically applicable in treating cholestatic liver diseases.
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Utilization of surveillance after polypectomy in the medicare population - a cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
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Surveillance in patients with previous polypectomy was underused in the Medicare population in 1994. This study investigates whether expansion of Medicare reimbursement for colonoscopy screening in high-risk individuals has reduced the inappropriate use of surveillance.
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Phosphomimetic mutation of cysteine string protein-? increases the rate of regulated exocytosis by modulating fusion pore dynamics in PC12 cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Cysteine string protein-? (CSP?) is a chaperone to ensure protein folding. Loss of CSP? function associates with many neurological diseases. However, its function in modulating regulated exocytosis remains elusive. Although csp?-knockouts exhibit impaired synaptic transmission, overexpression of CSP? in neuroendocrine cells inhibits secretion. These seemingly conflicting results lead to a hypothesis that CSP? may undergo a modification that switches its function in regulating neurotransmitter and hormone secretion. Previous studies implied that CSP? undergoes phosphorylation at Ser10 that may influence exocytosis by altering fusion pore dynamics. However, direct evidence is missing up to date.
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Protein phosphatase 4 is an essential positive regulator for Treg development, function, and protective gut immunity.
Cell Biosci
PUBLISHED: 01-01-2014
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Protein phosphates 4 (PP4), encoded by the ppp4c gene, is a ubiquitously expressed phosphatase that has been implicated in the regulation of cytokine signaling and lymphocyte survival; recent reports suggest that PP4 may be involved in pre-TCR signaling and B cell development. However, whether PP4 also modulates the functions of peripheral T cells has not been investigated due to the lack of a suitable in vivo model. Treg cells are a specialized subset of CD4 helper T cells that can suppress the proliferation of activated effector T cells. In the absence of this negative regulation, autoimmune syndromes and inflammatory diseases, such as human Crohn's disease, will arise.
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Hepatitis C virus infection among injection drug users with and without human immunodeficiency virus co-infection.
PLoS ONE
PUBLISHED: 01-01-2014
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The aim of this study is to explore the prevalence of hepatitis C virus (HCV) infection among injection drug users (IDUs) with and without human immunodeficiency virus (HIV) infection in southern Taiwan. For 562 IDUs (265 anti-HIV negative, 297 anti-HIV positive), we analyzed liver function, anti-HIV antibody, anti-HCV antibody, HCV viral loads, and hepatitis B surface antigen (HBsAg). HIV RNA viral loads and CD4 cell count for anti-HIV-seropositive IDUs and the HCV genotype for HCV RNA-seropositive IDUs were measured. The seroprevalence rates of anti-HIV, anti-HCV, and HBsAg were 52.8%, 91.3%, and 15.3%, respectively. All the anti-HIV-seropositive IDUs were positive for HIV RNA. Anti-HCV seropositivity was the most important factor associated with HIV infection (odds ratio [OR], 25.06; 95% confidence intervals [CI], 8.97-74.9), followed by male gender (OR, 6.12; 95% CI, 4.05-9.39) and HBsAg seropositivity (OR, 1.90; 95% CI, 1.11-3.34). Among IDUs positive for anti-HCV, 80.7% had detectable HCV RNA. HCV viremia after HCV exposure was strongly related to HIV infection (OR, 6.262; 95% CI, 1.515-18.28), but negatively correlated to HBsAg seropositivity (OR, 0.161; 95% CI, 0.082-0.317). HCV genotype 6 was the most prevalent genotype among all IDUs (41.0%), followed by genotypes 1 (32.3%), 3 (12.8%), and 2 (5.6%). In conclusion, about half IDUs were infected with HIV and >90% with HCV infection. Male and seropositivity for HBsAg and anti-HCV were factors related to HIV infection among our IDUs. HIV was positively correlated, whereas hepatitis B co-infection was negatively correlated with HCV viremia among IDUs with HCV exposure. Different HCV molecular epidemiology was noted among IDUs.
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Mapping the protein interaction network for the TFIIB-related factor Brf1 in the RNA polymerase III pre-initiation complex.
Mol. Cell. Biol.
PUBLISHED: 11-25-2013
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The TFIIB-related factor Brf1 is essential for RNA polymerase (Pol) III recruitment and open promoter formation in transcription initiation. We site-specifically incorporated non-natural amino acid cross-linker to Brf1 to map its protein interaction targets in the pre-initiation complex (PIC). Our cross-linking analysis in the N-terminal domain of Brf1 indicated a pattern of multiple protein interactions reminiscent of TFIIB in the polymerase active site cleft. In addition to the TFIIB-like protein interactions, the Brf1 cyclin repeats subdomain is in contact with the Pol III-specific C34 subunit. With site-directed hydroxyl radical probing, we further revealed the binding between Brf1 cyclin repeats and the highly conserved region connecting C34 winged-helix domains 2 and 3. In contrast to the N-terminal domain of Brf1, the C-terminal domain contains extensive binding sites for TBP and Bdp1 to hold together the TFIIIB complex on the promoter. Overall, the domain architecture of the PIC derived from our cross-linking data explains how individual structural subdomains of Brf1 integrate the protein network from the Pol III active center to the promoter for transcription initiation.
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Acute Meningitis Caused by Cladosporium sphaerospermum.
Am. J. Med. Sci.
PUBLISHED: 11-23-2013
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: Phaeohyphomycosis of the central nervous system is rare but typically associated with high mortality. Treatment has not been standardized, but the combination of antifungal chemotherapy with surgical debridement is recommended. We report a 73-year-old, retired, male timber merchant with acute meningitis caused by Cladosporium sphaerospermum. The patient, who had well-controlled type 2 diabetes mellitus, presented with fever and weakness of the lower limbs. No brain abscess was apparent by cranial computed tomography. C. sphaerospermum was isolated from the cerebral spinal fluid and identified based on both morphology and DNA sequencing. He was treated with combination antifungal chemotherapy with amphotericin B and voriconazole for 28 days, followed by voriconazole monotherapy for 46 days. To date, the patient has recovered without significant sequelae. This patient represents the first reported case of cerebral phaeohyphomycosis caused by C. sphaerospermum. Moreover, the therapy was successful for totally less than 3 months of treatment duration.
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Dispersion Force Stabilized Two-Coordinate Transition Metal-Amido Complexes of the -N(SiMe3)Dipp (Dipp = C6H3-2,6-Pr(i)2) Ligand: Structural, Spectroscopic, Magnetic, and Computational Studies.
Inorg Chem
PUBLISHED: 11-18-2013
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A series of high spin, two-coordinate first row transition metal-amido complexes, M{N(SiMe3)Dipp}2 {M = Fe (1), Co (2), or Ni (3); Dipp = C6H3-2,6-Pr(i)2} and a tetranuclear C-H activated chromium amide, [Cr{N(SiMe2CH2)Dipp}2Cr]2(THF) (4), were synthesized by reaction of their respective metal dihalides with 2 equiv of the lithium amide salt. They were characterized by X-ray crystallography, electronic and infrared spectroscopy, SQUID magnetic measurements, and computational methods. Contrary to steric considerations, the structures of 1-3 display planar eclipsed M{NSiC(ipso)}2 arrays and short M-N distances. DFT calculations, corrected for dispersion effects, show that dispersion interactions involving C-H-H-C moieties likely stabilize the structures by 21.1-29.4 kcal mol(-1), depending on the level of the calculations employed. SQUID measurements confirm high spin electron configurations for all the complexes and substantial orbital contributions for 1 and 2.
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Synthesis and evaluation of a photoactive probe with a multivalent carbohydrate for capturing carbohydrate-lectin interactions.
Bioconjug. Chem.
PUBLISHED: 11-06-2013
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Lectins are ubiquitous carbohydrate-binding proteins of nonimmune origin that are characterized by their specific recognition of defined monosaccharide or oligosaccharide structures. However, the use of carbohydrates to study lectin has been restricted by the weak binding affinity and noncovalent character of the interaction between carbohydrates and lectin. In this report, we designed and synthesized a multifunctional photoaffinity reagent composed of a trialkyne chain, a masked latent amine group, and a photoreactive 3-trifluoromethyl-3-phenyl-diazirine group in high overall yield. Two well-defined chemistries, Huisgen-Sharpless click chemistry and amide bond coupling, were the key steps for installing the multivalent character and tag in our designed photoaffinity probe. The photolabeling results demonstrated that the designed probe selectively labeled the target lectin, RCA120 ( Ricinus communis Agglutinin), in an E. coli lysate and an asialoglycoprotein receptor (ASGP-R) on intact HepG2 cell membranes. Moreover, the probe also enabled the detection of weak protein-protein interactions between RCA120 and ovalbumin (OVA).
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Effect of intragastric balloon on gastric emptying time in humans for weight control.
Clin Nucl Med
PUBLISHED: 10-04-2013
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This study evaluated the effect of fluid-filled intragastric balloon treatment on the scintigraphic gastric emptying times in humans for weight control.
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Transcriptional repressor HipB regulates the multiple promoters in Escherichia coli.
J. Mol. Microbiol. Biotechnol.
PUBLISHED: 09-27-2013
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HipB is a DNA-binding protein in Escherichia coli and negatively regulates its own promoter by binding to the palindromic sequences [TATCCN8GGATA (N represents any nucleotides)] on the hipBA promoter. For such sequences, bioinformatic analysis revealed that there are a total of 39 palindromic sequences (TATCCN(x)GGATA: N is any nucleotides and x is the number of nucleotides from 1 to 30) in the promoter regions of 33 genes on the E. coli genome. Notably, eutH and fadH have two and three TATCCN(x)GGATA palindromic sequences located in their promoters, respectively. Another significant finding was that a palindromic sequence was also identified in the promoter region of hipAB locus, known to be involved in the RelA-dependent persister cell formation in bacteria. Here, we demonstrated that HipB binds to the palindromic structures in the eutH, fadH, as well as the relA promoter regions and represses their expressions. We further demonstrated that HipA enhances the repression of the relA promoter activity by HipB. This effect was not observed with D291A HipA mutant which was previously shown to lack an ability to interact with HipB, indicating that HipA enhances the HipBs repressor activity through direct interaction with HipB.
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Synthesis of sialic acid-containing saccharides.
Curr Opin Chem Biol
PUBLISHED: 08-01-2013
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Sialic acids are a diverse family of negatively charged monosaccharides with a shared nine-carbon carboxylated backbone, and they often serve as the terminal positions of cell surface glycoproteins and glycolipids. Sialic acids play essential roles in mediating or modulating numerous pathological, biological, and immunological recognition events. Advances in synthesis have provided chemically well-defined and structurally homogeneous sialic acid-containing carbohydrates that are crucial for studying glycobiology. This review highlights recent innovations in the chemical and chemoenzymatic synthesis of difficult ?-sialosides, with a particular focus on methods developed for ?-selective sialylation in the synthesis of O-linked and S-linked oligosialic acids.
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High-throughput fabrication of gray-level biomicrostructures via temporal focusing excitation and laser pulse control.
J Biomed Opt
PUBLISHED: 07-27-2013
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ABSTRACT. A developed temporal focusing-based multiphoton excitation system with additional patterned excitation and local laser control can provide high-throughput fabrication of three-dimensional gray-level biomicrostructures via two-photon cross-linking with rose bengal (RB) as the photoactivator. Multiple bovine serum albumin (BSA) structures of different concentrations were simultaneously achieved by selecting different pulse numbers in the designated regions with an appropriate femtosecond laser power within a few seconds. Intensity of the RB two-photon excited fluorescence (TPEF) is correlated to the concentration of the fabricated cross-linked BSA microstructure. Hence, the fabricated BSA microstructure can be monitored online by utilizing the RB TPEF as contrast agent. It suggests that this approach with its unique capability of high-speed, gray-level, and online-inspection fabrication meets the requirements of the biomedical researches involved in extracellular matrix.
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Concomitance of cervical intramedullary traumatic neuroma and cervical cord herniation in a tetraplegic woman.
J Back Musculoskelet Rehabil
PUBLISHED: 07-27-2013
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We present the first case of concomitant intramedullary traumatic neuroma and spinal cord herniation. A 57-year-old woman injured her cervical spine with subluxation and cord compression at the C5-C6 level. After the operation, the patient received intensive rehabilitation for one year with well response. Unfortunately, she experienced weakness and progressive numbness extending to all the limbs later. Cervical magnetic resonance imaging revealed spinal cord herniation at the C5-C6 level and pathology proved intramedullary traumatic neuroma. After the second operation, the paresthesia over the trunk and limbs persisted, and the patient was nearly totally assisted in her activities of daily living. The intramedullary traumatic neuroma and spinal cord herniation are rare causes in patients with spinal cord dysfunction. The case presented here indicates the possibility of the coexisting conditions leading to progressive neurologic deficits in patients with old spinal cord injury.
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Alzheimers amyloid-? oligomers rescue cellular prion protein induced tau reduction via the Fyn pathway.
ACS Chem Neurosci
PUBLISHED: 07-18-2013
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Amyloid-? (A?) and tau are the pathogenic hallmarks in Alzheimers disease (AD). A? oligomers are considered the actual toxic entities, and the toxicity relies on the presence of tau. Recently, A? oligomers have been shown to specifically interact with cellular prion protein (PrP(C)) where the role of PrP(C) in AD is still not fully understood. To investigate the downstream mechanism of PrP(C) and A? oligomer interaction and their possible relationships to tau, we examined tau expression in human neuroblastoma BE(2)-C cells transfected with murine PrP(C) and studied the effect under A? oligomer treatment. By Western blotting, we found that PrP(C) overexpression down-regulated tau protein and A? oligomer binding alleviated the tau reduction induced by wild type but not M128V PrP(C), the high AD risk polymorphic allele in human prion gene. PrP(C) lacking the A? oligomer binding site was incapable of rescuing the level of tau reduction. Quantitative RT-PCR showed the PrP(C) effect was attributed to tau reduction at the transcription level. Treatment with Fyn pathway inhibitors, Fyn kinase inhibitor PP2 and MEK inhibitor U0126, reversed the PrP(C)-induced tau reduction and A? oligomer treatment modulated Fyn kinase activity. The results suggested Fyn pathway regulated A?-PrP(C)-tau signaling. Overall, our results demonstrated that PrP(C) down-regulated tau via the Fyn pathway and the effect can be regulated by A? oligomers. Our study facilitated the understanding of molecular mechanisms among PrP(C), tau, and A? oligomers.
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Implantable stimulator for epileptic seizure suppression with loading impedance adaptability.
IEEE Trans Biomed Circuits Syst
PUBLISHED: 07-16-2013
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The implantable stimulator for epileptic seizure suppression with loading impedance adaptability was proposed in this work. The stimulator consisted of the high voltage generator, output driver, adaptor, and switches, can constantly provide the required 40-?A stimulus currents, as the loading impedance varied within 10 k? -300 k?. The performances of this design have been successfully verified in silicon chip fabricated by a 0.35- ?m 3.3-V/24-V CMOS process. The power consumption of this work was only 1.1 mW-1.4 mW. The animal test results with the fabricated chip of proposed design have successfully verified in the Long-Evans rats with epileptic seizures.
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Ultrasonic spectrum analysis for in vivo characterization of tumor microstructural changes in the evaluation of tumor response to chemotherapy using diagnostic ultrasound.
BMC Cancer
PUBLISHED: 06-14-2013
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There is a strong need for early assessment of tumor response to chemotherapy in order to avoid the adverse effects of unnecessary chemotherapy and to allow early transition to second-line therapy. The purpose of this study was to determine the feasibility of ultrasonic spectral analysis for the in vivo characterization of changes in tumor microstructure in the evaluation of tumor response to chemotherapy using diagnostic ultrasound.
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Determinants of the combined use of external beam radiotherapy and brachytherapy for low-risk, clinically localized prostate cancer.
Cancer
PUBLISHED: 05-17-2013
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Prostate cancer treatment choices have been shown to vary by physician and patient characteristics. For patients with low-risk, clinically localized prostate cancer, the authors examined the impact of their clinical, sociodemographic, and radiation oncologists (RO) characteristics on the likelihood that the patients would receive combined external beam radiotherapy and brachytherapy, a treatment regimen that is at variance with clinical guidelines.
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The small GTPase HRas shapes local PI3K signals through positive feedback and regulates persistent membrane extension in migrating fibroblasts.
Mol. Biol. Cell
PUBLISHED: 05-15-2013
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Self-amplification of phosphoinositide 3-kinase (PI3K) signaling is believed to regulate asymmetric membrane extension and cell migration, but the molecular organization of the underlying feedback circuit is elusive. Here we use an inducible approach to synthetically activate PI3K and interrogate the feedback circuitry governing self-enhancement of 3-phosphoinositide (3-PI) signals in NIH3T3 fibroblasts. Synthetic activation of PI3K initially leads to uniform production of 3-PIs at the plasma membrane, followed by the appearance of asymmetric and highly amplified 3-PI signals. A detailed spatiotemporal analysis shows that local self-amplifying 3-PI signals drive rapid membrane extension with remarkable directional persistence and initiate a robust migratory response. This positive feedback loop is critically dependent on the small GTPase HRas. Silencing of HRas abrogates local amplification of 3-PI signals upon synthetic PI3K activation and results in short-lived protrusion events that do not support cell migration. Finally, our data indicate that this feedback circuit is likely to operate during platelet-derived growth factor-induced random cell migration. We conclude that positive feedback between PI3K and HRas is essential for fibroblasts to spontaneously self-organize and generate a productive migratory response in the absence of spatial cues.
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Increased production of interleukin-4, interleukin-10, and granulocyte-macrophage colony-stimulating factor by type 2 diabetes mononuclear cells infected with dengue virus, but not increased intracellular viral multiplication.
Biomed Res Int
PUBLISHED: 05-09-2013
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It has been reported that diabetes mellitus (DM) was an epidemiologically identified risk factor for development of dengue hemorrhagic fever (DHF)/severe dengue in dengue virus (DENV) affected patients, and T helper 2 (Th2) cytokines such as interleukin-4 (IL-4) and IL-10 each plays an important role in the immunopathogenesis of DHF in studies involving general population. To better understand the relationship between these epidemiological and immunological findings, we performed an in vitro study evaluating the sequential immunological reactions and viral load in the DENV infected mononuclear cells of adults with type 2 DM (T2DM group, n = 33) and normal adults (control group, n = 29). We found in the T2DM group significantly higher IL-4 level on the first (P = 0.049) and the third (P = 0.022) postinfection days, while higher IL-10 (P = 0.042) and granulocyte-macrophage colony-stimulating factor (GM-CSF) (P = 0.009) were detected on the third postinfection day. No significant difference in DENV viral load between the cultured mononuclear cells from both groups was found on the first and third post-infection days. These data immunologically suggest that patients with T2DM are at higher risk for development of DHF/severe dengue and strengthen the previously epidemiologically identified role of DM being a predictive risk factor for progressing into DHF/severe dengue in DENV-affected patients.
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Rapid modifications of N-substitution in iminosugars: development of new ?-glucocerebrosidase inhibitors and pharmacological chaperones for Gaucher disease.
Bioorg. Med. Chem.
PUBLISHED: 05-05-2013
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The rapid discovery of ?-glucocerebrosidase (GCase) inhibitors and pharmacological chaperones for Gaucher disease is described. The N-aminobutyl DNJ-based iminosugar was synthesized and conjugating with a variety of carboxylic acids to generate a N-diversely substituted iminosugar-based library. Several members of this library were found to be nanomolar-range inhibitors of GCase; the inhibition constant Ki of the most potent was found to be 71nM. Although these new molecules showed reasonable chaperoning activity (1.5- to 1.9-fold) in the N370S fibroblast of Gaucher patient-derived cell line, this was accompanies by a concomitant decrease in the cellular ?-glucosidase activity, which might limit their further therapeutic potential. Next, newly developed N-substituents were assembled with pyrrolidine-based scaffolds to generate new molecules for further evaluation. The new 2,5-dideoxy-2,5-imino-d-mannitol (DMDP)-based iminosugar 22 was found to exhibit a satisfactory chaperoning activity to enhance GCase activity by 2.2-fold in Gaucher N370S cell line, without impairment of cellular ?-glucosidase activity.
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Association between the availability of medical oncologists and initiation of chemotherapy for patients with stage III colon cancer.
J Oncol Pract
PUBLISHED: 05-02-2013
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Although the number of medical oncologists (MOs) has steadily increased over time, and adjuvant chemotherapy provides significant survival benefit for patients with stage III colon cancer, many patients still do not receive chemotherapy. Uneven geographic distribution of MOs may contribute to decreasing access to cancer care. This study explored the association of MO availability by hospital service area (HSA) of patient residence and access to chemotherapy treatment.
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Klebsiella pneumoniae bacteremia and renosplenic abscesses without intestinal symptoms as the initial manifestations of non-steroidal anti-inflammatory drug-induced colitis: a rare case report.
BMC Gastroenterol
PUBLISHED: 04-26-2013
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Non-steroidal anti-inflammatory drugs (NSAIDs), the most widely prescribed drugs in the world, can cause gastrointestinal damage, including colitis. However, the prevalence of NSAID-induced colitis is unknown because the disease is often asymptomatic.
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(11)C-Acetate as a new biomarker for PET/CT in patients with multiple myeloma: initial staging and postinduction response assessment.
Eur. J. Nucl. Med. Mol. Imaging
PUBLISHED: 04-04-2013
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We investigated the potential value of (11)C-acetate (ACT) PET/CT in characterizing multiple myeloma (MM) compared with (18)F-FDG PET/CT. Bone marrow histological and whole-body (WB) MRI findings served as the reference standards.
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Prevalence of and associated factors with chronic kidney disease in human immunodeficiency virus-infected patients in Taiwan.
J Microbiol Immunol Infect
PUBLISHED: 04-03-2013
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Chronic kidney disease (CKD) is an important issue for individuals who live with human immunodeficiency virus (HIV) following the use of highly active antiretroviral therapy; however, the prevalence rate of CKD varies between countries.
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Spheroid formation and enhanced cardiomyogenic potential of adipose-derived stem cells grown on chitosan.
Biores Open Access
PUBLISHED: 03-22-2013
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Mesenchymal stem cells may differentiate into cardiomyocytes and participate in local tissue repair after heart injury. In the current study, rat adipose-derived adult stem cells (ASCs) grown on chitosan membranes were observed to form cell spheroids after 3 days. The cell seeding density and surface modification of chitosan with Arg-Gly-Asp-containing peptide had an influence on the sizes of ASC spheroids. In the absence of induction, these spheroids showed an increased level of cardiac marker gene expression (Gata4, Nkx2-5, Myh6, and Tnnt2) more than 20-fold versus cells on the tissue culture polystyrene (TCPS) dish. Induction by 5-azacytidine or p38 MAP kinase inhibitor (SB202190) did not further increase the cardiac marker gene expression of these spheroids. Moreover, the enhanced cardiomyogenic potential of the spheroids was highly associated with the chitosan substrates. When ASC spheroids were plated onto TCPS with either basal or cardiac induction medium for 9 days, the spheroids spread into a monolayer and the positive effect on cardiomyogenic marker gene expression disappeared. The possible role of calcium ion and the up-regulation of adhesion molecule P-selectin and chemokine receptor Cxcr4 were demonstrated in ASC spheroids. Applying these spheroids to the chronic myocardial infarction animal model showed better functional recovery versus single cells after 12 weeks. Taken together, this study suggested that the ASC spheroids on chitosan may form as a result of calcium ion signaling, and the transplantation of these spheroids may offer a simple method to enhance the efficiency of stem cell-based therapy in myocardial infarction.
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Chemically inducible diffusion trap at cilia reveals molecular sieve-like barrier.
Nat. Chem. Biol.
PUBLISHED: 03-11-2013
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Primary cilia function as specialized compartments for signal transduction. The stereotyped structure and signaling function of cilia inextricably depend on the selective segregation of molecules in cilia. However, the fundamental principles governing the access of soluble proteins to primary cilia remain unresolved. We developed a methodology termed chemically inducible diffusion trap at cilia to visualize the diffusion process of a series of fluorescent proteins ranging in size from 3.2 nm to 7.9 nm into primary cilia. We found that the interior of the cilium was accessible to proteins as large as 7.9 nm. The kinetics of ciliary accumulation of this panel of proteins was exponentially limited by their Stokes radii. Quantitative modeling suggests that the diffusion barrier operates as a molecular sieve at the base of cilia. Our study presents a set of powerful, generally applicable tools for the quantitative monitoring of ciliary protein diffusion under both physiological and pathological conditions.
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Simvastatin attenuates the additive effects of TNF-? and IL-18 on the connexin 43 up-regulation and over-proliferation of cultured aortic smooth muscle cells.
Cytokine
PUBLISHED: 03-11-2013
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Statin therapy is known to down-regulate inflammatory activities in atheromatous tissues of animals. The aims of this study were to examine the regulatory role of interleukin-18 (IL-18) in the connexin 43 (Cx43) and the proliferation of cultured aortic smooth muscle cells (SMCs) as well as to elucidate the underlying therapeutic mechanism of simvastatin. Vytorin therapy significantly alleviated high-cholesterol diet-induced hypercholesterolemia, suppressed neointimal hyperplasia, macrophage infiltration, and Cx43 and IL-18 expression in rabbit aortic walls. In vitro study using an aortic SMC line showed that IL-18 up-regulated constitutive Cx43 expression and potentiated tumor necrosis factor-? (TNF-?)-triggered Akt and MAPK signaling pathways. Simvastatin treatment alone reduced constitutive Cx43 levels and prevented the TNF-?-induced IL-18 up-regulation. Mechanistic investigation using kinase-specific inhibitors showed that simvastatin pretreatment attenuated TNF-?-elicited Akt and ERK1/2 phosphorylation, whereas PI3K and all MAPK activities were also implied in the additive effect of TNF-? and IL-18 on Cx43 up-regulation. Proliferation assay indicated that IL-18 stimulated SMC proliferation and synergized the TNF-?-stimulated cell proliferation. Likewise, simvastatin treatment suppressed the SMC over-proliferation induced not only by TNF-? alone, but also by simultaneous treatment with TNF-? and IL-18. The suppression of simvastatin in SMC proliferation was not mediated through mitochondrial related pro-apoptogenesis under both scenarios. In conclusion, simvastatin attenuates the additive effects of TNF-? and IL-18 on Cx43 up-regulation and over-proliferation of aortic SMCs, mainly through the blockade of Akt signaling pathway. These findings may fortify the rationale underlying the atheroprotective mechanism of statin therapy.
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Arteriovenous graft infection caused by Candida glabrata: A case report and literature review.
J Microbiol Immunol Infect
PUBLISHED: 03-09-2013
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The infection rate of arteriovenous (AV) grafts is high, but fungal etiology is rare. Only five cases of graft infection due to Candida albicans (C. albicans) or C. tropicalis have been described in the literature. Herein, we report the first case of AV graft infection caused by C. glabrata. A 60-year-old woman on maintenance hemodialysis for end-stage renal disease was admitted because of intermittent fever, for 10 days. Upon physical examination, tenderness over the AV graft site was noticed. Blood culture yielded C. glabrata and her clinical symptoms improved after she was treated with micafungin for 1 month. However, C. glabrata candidemia reoccurred 5 weeks later. Cure was achieved after removal of the AV graft and anidulafungin treatment. Pus was observed in the removed graft, from which C. glabrata was isolated. The outcome of our case and patients from the literature review suggest that removal of the infected graft is important for treatment success of AV graft Candida infection.
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Visualizing molecular diffusion through passive permeability barriers in cells: conventional and novel approaches.
Curr Opin Chem Biol
PUBLISHED: 03-04-2013
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Diffusion barriers are universal solutions for cells to achieve distinct organizations, compositions, and activities within a limited space. The influence of diffusion barriers on the spatiotemporal dynamics of signaling molecules often determines cellular physiology and functions. Over the years, the passive permeability barriers in various subcellular locales have been characterized using elaborate analytical techniques. In this review, we will summarize the current state of knowledge on the various passive permeability barriers present in mammalian cells. We will conclude with a description of several conventional techniques and one new approach based on chemically inducible diffusion trap (CIDT) for probing permeable barriers.
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FDG PET or PET/CT in evaluation of renal angiomyolipoma.
Korean J Radiol
PUBLISHED: 02-22-2013
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Angiomyolipoma is the most common benign kidney tumor. However, literature describing FDG PET findings on renal angiomyolipoma (AML) is limited. This study reports the FDG PET and PET/CT findings of 21 cases of renal AML.
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Role of a novel functional variant in the PPP2R1A promoter on the regulation of PP2A-Aalpha and the risk of hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 02-15-2013
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Previously, we identified the genetic variant -241 (-/G) (rs11453459) in the PP2A-A? gene (PPP2R1A) promoter and demonstrated that this variant influences the DNA-binding affinity of nuclear factor-kappa B (NF-?B). In this study, we further confirmed that the transcriptional activity of PPP2R1A may be regulated by NF-?B through the functional genetic variant -241 (-/G). Moreover, we also demonstrated that the methylation status of CpG islands in the promoter of PPP2R1A influences the activity of this gene promoter. Few studies have examined the role of this -241 (-/G) variant in genetic or epigenetic regulation in hepatocellular carcinoma (HCC). To investigate whether this functional variant in the PPP2R1A promoter is associated with the risk of HCC and confirm the function of the -241 (-/G) variant in the HCC population, we conducted a case-control study involving 251 HCC cases and 252 cancer-free controls from a Han population in southern China. Compared with the -241 (--) homozygote, the heterozygous -241 (-G) genotype (adjusted OR ?=?0.32, 95% confidence interval (CI) ?=?0.17-0.58, P<0.001) and the -241 (-G)/(GG) genotypes (adjusted OR ?=?0.38, 95% CI ?=?0.22-0.67, P ?=?0.001) were both significantly associated with a reduced risk of HCC. Stratification analysis indicated that the protective role of -241 (-G) was more pronounced in individuals who were ? 40 years of age, female and HBV-negative. Our data suggest that the transcriptional activity of PPP2R1A is regulated by NF-?B through the -241 (-/G) variant and by the methylation of the promoter region. Moreover, the functional -241 (-/G) variant in the PPP2R1A promoter contributes to the decreased risk of HCC. These findings contribute novel information regarding the gene transcription of PPP2R1A regulated by the polymorphism and methylation in the promoter region through genetic and epigenetic mechanisms in hepatocarcinogenesis.
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CT-guided core needle biopsy of deep suprahyoid head and neck lesions in untreated patients.
Interv Neuroradiol
PUBLISHED: 01-29-2013
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This study aimed to evaluate the efficacy of CT-guided core needle biopsy (CNB) in the diagnosis of deep head and neck tumors in untreated patients. We retrospectively reviewed the records of ten consecutive CT-guided CNB procedures from ten patients without a related history from March 2004 to February 2012. The surgical results, treatment response and clinical follow-up were used as the diagnostic standards. All specimens were considered adequate. Nine out of ten cases matched the final diagnosis. Biopsy failed to diagnose the infratemporal meningioma en plaque in a particular case. Three cases were carcinomas. No complication was encountered. CT-guided core needle biopsy is an efficient and safe technique for histological diagnosis of skull base lesions in patients without a related history. This technique can offer a definite tissue diagnosis and avoid unnecessary surgical interventions for such patients.
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Inferring homologous protein-protein interactions through pair position specific scoring matrix.
BMC Bioinformatics
PUBLISHED: 01-21-2013
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The protein-protein interaction (PPI) is one of the most important features to understand biological processes. For a PPI, the physical domain-domain interaction (DDI) plays the key role for biology functions. In the post-genomic era, to rapidly identify homologous PPIs for analyzing the contact residue pairs of their interfaces within DDIs on a genomic scale is essential to determine PPI networks and the PPI interface evolution across multiple species.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.