554 research outputs found

    A unique seasonal pattern in dissolved elemental mercury in the South China Sea, a tropical and monsoon-dominated marginal sea

    Get PDF
    Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 40 (2013): 167–172, doi:10.1029/2012GL054457.A unique seasonal pattern in dissolved elemental mercury (DEM) was observed in the tropical monsoon-dominated South China Sea (SCS). The DEM concentration varied seasonally, with a high in summer of 160 ± 40 fM (net evasion 580 ± 120 pmol m−2 d−1, n = 4) and a low in winter of 60 ± 30 fM (net invasion −180 ± 110, n = 4) and showed a positive correlation with sea surface temperature (SST). The elevated DEM concentration in summer appears mainly abiologically driven. In winter, the SCS acts as a sink of atmosphere Hg0 as a result of low SST and high wind of the year, enhanced vertical mixing, and elevated atmospheric gaseous elemental mercury. Annually, the SCS serves as a source of Hg0 to the atmosphere of 300 ± 50 pmol m−2 d−1 (385 ± 64 kmol Hg yr−1, ~2.6% of global emission in ~1% of global ocean area), suggesting high regional Hg pollution impacts from the surrounding Mainland (mostly China).Support was provided by the National Science Council through grants NSC 97-2745-M-002- 001-;98(99,100)-2611-M-002-013(014,004) and from the College of Science, National Taiwan University under the “Drunken Moon Lake Scientific Integrated Scientific Research Platform” grant, NTU 101R3252, as well as through the U.S. National Science Foundation under grant OCE-1132515 and 0928191.2013-07-1

    Percutaneous Transhepatic Cholangiography and Drainage is an Effective Rescue Therapy for Biliary Complications in Liver Transplant Recipients Who Fail Endoscopic Retrograde Cholangiopancreatography

    Get PDF
    BackgroundWe attempted to evaluate both the factors that predispose a patient to biliary complications after liver transplantation and the results of percutaneous transhepatic cholangiography and drainage (PTCD) for the management of those complications.MethodsThis study retrospectively reviewed the cases of 81 patients who received liver transplants at Taipei Veterans General Hospital between February 2003 and June 2008. Biliary complications were diagnosed on the basis of clinical findings, laboratory data, and the results of imaging studies.ResultsA total of 18 patients (22.2%) developed biliary complications, and living donor liver transplantation (LDLT) was a significant risk factor (p = 0.035), compared to cadaveric liver transplantation. Eight patients with biliary complications received PTCD as the first treatment modality and 6 had successful results. An additional 10 patients received endoscopic retrograde cholangiopancreatography (ERCP) initially, but only 2 patients were effectively managed. One patient received conservative treatment after ERCP failure. One patient died from sepsis after ERCP. The remaining 6 patients with failed ERCP were successfully managed with PTCD. The overall mortality rate in these patients with biliary complications was 16.7%. No significant prognostic predictors were identified, including age, sex, biochemical data, and model for end-stage liver disease scores.ConclusionBiochemical markers cannot predict biliary complications preoperatively. LDLT increases the risk of biliary complications. PTCD is an effective rescue therapy when ERCP fails

    Construction of Fuzzy Map for Autonomous Mobile Robots Based on Fuzzy Confidence Model

    Get PDF
    This paper presents the use of fuzzy models to explicitly consider sensor uncertainty and finite resolution in solving the SLAM (simultaneous localization and mapping) problem for autonomous mobile robots. The approach establishes fuzzy confidence models in describing occupied obstacles and available space. The problem is transformed into an optimization task of minimizing the alignment error between newly scanned local fuzzy maps and selected parts of a developing global fuzzy map. In aligning local fuzzy maps into a global fuzzy map, we developed a prediction strategy to crop the most potential part from the sensed local fuzzy maps to be overlapped with the global fuzzy map. A mobile vehicle equipped with a laser range finder, the Hokuyo URG-04LX, is used to demonstrate the procedure of fuzzy map building. Experimental results show that the proposed architecture is effective in generating a comprehensive global fuzzy map, which is suitable for both human comprehension and path design during real-time navigation

    Establishing a risk scoring system for predicting erosive esophagitis

    Get PDF
    SummaryObjectiveThis study aims to establish a noninvasive scoring system to predict the risk of erosive esophagitis (EE).MethodsFrom 2002 to 2009, a total of 34,346 consecutive adults who underwent health check-ups and upper gastrointestinal endoscopy were retrospectively enrolled. Of the participants, 22,892 in the earlier two-thirds period of examination were defined as the training set and the remaining 11,454 as the validation set. EE was diagnosed by upper gastrointestinal endoscopy. Independent risk factors associated with EE were analyzed by multivariate analysis using a logistic regression model with the forward stepwise selection procedure in the training set. Subsequently, an EE risk scoring system was established and weighted by β coefficient. This risk scoring system was further validated in the validation set.ResultsIn the training set, older age, male gender, higher body mass index, higher waist circumference, higher serum triglyceride, and lower high-density lipid cholesterol levels were independent risk factors for predicting EE. According to the β coefficient value of each independent risk factor, the total score ranging from 0 to 10 was established, and then low- (0–3), moderate- (4–6), and high-risk (7–10) groups were identified. In the validation set, the prevalence rates of EE in the low-, moderate-, and high-risk groups were 5.15%, 15.76% and 26.11%, respectively (p < 0.001).ConclusionThis simple noninvasive risk scoring system, including factors of age, gender, body mass index, waist circumference, triglyceride, and high-density lipid cholesterol, effectively predicted EE and stratified its incidence

    Bmi-1 Regulates Snail Expression and Promotes Metastasis Ability in Head and Neck Squamous Cancer-Derived ALDH1 Positive Cells

    Get PDF
    Recent studies suggest that ALDH1 is a putative marker for HNSCC-derived cancer stem cells. However, the regulation mechanisms that maintain the stemness and metastatic capability of HNSCC-ALDH1+ cells remain unclear. Initially, HNSCC-ALDH1+ cells from HNSCC patient showed cancer stemness properties, and high expression of Bmi1 and Snail. Functionally, tumorigenic properties of HNSCC-ALDH1+ cells could be downregulated by knockdown of Bmi-1. Overexpression of Bmi-1 altered in expression property ALDH1− cells to that of ALDH1+ cells. Furthermore, knockdown of Bmi-1 enhanced the radiosensitivity of radiation-treated HNSCC-ALDH1+ cells. Moreover, overexpression of Bmi-1 in HNSCC-ALDH1− cells increased tumor volume and number of pulmonary metastatic lesions by xenotransplant assay. Importantly, knock-down of Bmi1 in HNSCC-ALDH1+ cells significantly decreased distant metastases in the lungs. Clinically, coexpression of Bmi-1/Snail/ALDH1 predicted the worst prognosis in HNSCC patients. Collectively, our data suggested that Bmi-1 plays a key role in regulating Snail expression and cancer stemness properties of HNSCC-ALDH1+ cells

    Benchmarking of eight recurrent neural network variants for breath phase and adventitious sound detection on a self-developed open-access lung sound database-HF_Lung_V1

    Full text link
    A reliable, remote, and continuous real-time respiratory sound monitor with automated respiratory sound analysis ability is urgently required in many clinical scenarios-such as in monitoring disease progression of coronavirus disease 2019-to replace conventional auscultation with a handheld stethoscope. However, a robust computerized respiratory sound analysis algorithm has not yet been validated in practical applications. In this study, we developed a lung sound database (HF_Lung_V1) comprising 9,765 audio files of lung sounds (duration of 15 s each), 34,095 inhalation labels, 18,349 exhalation labels, 13,883 continuous adventitious sound (CAS) labels (comprising 8,457 wheeze labels, 686 stridor labels, and 4,740 rhonchi labels), and 15,606 discontinuous adventitious sound labels (all crackles). We conducted benchmark tests for long short-term memory (LSTM), gated recurrent unit (GRU), bidirectional LSTM (BiLSTM), bidirectional GRU (BiGRU), convolutional neural network (CNN)-LSTM, CNN-GRU, CNN-BiLSTM, and CNN-BiGRU models for breath phase detection and adventitious sound detection. We also conducted a performance comparison between the LSTM-based and GRU-based models, between unidirectional and bidirectional models, and between models with and without a CNN. The results revealed that these models exhibited adequate performance in lung sound analysis. The GRU-based models outperformed, in terms of F1 scores and areas under the receiver operating characteristic curves, the LSTM-based models in most of the defined tasks. Furthermore, all bidirectional models outperformed their unidirectional counterparts. Finally, the addition of a CNN improved the accuracy of lung sound analysis, especially in the CAS detection tasks.Comment: 48 pages, 8 figures. To be submitte

    Korean Red Ginseng Improves Blood Pressure Stability in Patients with Intradialytic Hypotension

    Get PDF
    Introduction. Intradialytic hypotension (IDH) is a common complication during hemodialysis which may increase mortality risks. Low dose of Korean red ginseng (KRG) has been reported to increase blood pressure. Whether KRG can improve hemodynamic stability during hemodialysis has not been examined. Methods. The 8-week study consisted of two phases: observation phase and active treatment phase. According to prehemodialysis blood pressure (BP), 38 patients with IDH were divided into group A (BP ≥ 140/90 mmHg, n = 18) and group B (BP < 140/90 mmHg, n = 20). Patients were instructed to chew 3.5 gm KRG slices at each hemodialysis session during the 4-week treatment phase. Blood pressure changes, number of sessions disturbed by symptomatic IDH, plasma levels of vasoconstrictors, blood biochemistry, and adverse effects were recorded. Results. KRG significantly reduced the degree of blood pressure drop during hemodialysis (P < 0.05) and the frequency of symptomatic IDH (P < 0.05). More activation of vasoconstrictors (endothelin-1 and angiotensin II) during hemodialysis was found. The postdialytic levels of endothelin-1 and angiotensin II increased significantly (P < 0.01). Conclusion. Chewing KRG renders IDH patients better resistance to acute BP reduction during hemodialysis via activation of vasoconstrictors. Our results suggest that KRG could be an adjuvant treatment for IDH

    Revealing the Anti-Tumor Effect of Artificial miRNA p-27-5p on Human Breast Carcinoma Cell Line T-47D

    Get PDF
    microRNAs (miRNAs) cause mRNA degradation or translation suppression of their target genes. Previous studies have found direct involvement of miRNAs in cancer initiation and progression. Artificial miRNAs, designed to target single or multiple genes of interest, provide a new therapeutic strategy for cancer. This study investigates the anti-tumor effect of a novel artificial miRNA, miR P-27-5p, on breast cancer. In this study, we reveal that miR P-27-5p downregulates the differential gene expressions associated with the protein modification process and regulation of cell cycle in T-47D cells. Introduction of this novel artificial miRNA, miR P-27-5p, into breast cell lines inhibits cell proliferation and induces the first “gap” phase (G1) cell cycle arrest in cancer cell lines but does not affect normal breast cells. We further show that miR P-27-5p targets the 3′-untranslated mRNA region (3′-UTR) of cyclin-dependent kinase 4 (CDK4) and reduces both the mRNA and protein level of CDK4, which in turn, interferes with phosphorylation of the retinoblastoma protein (RB1). Overall, our data suggest that the effects of miR p-27-5p on cell proliferation and G1 cell cycle arrest are through the downregulation of CDK4 and the suppression of RB1 phosphorylation. This study opens avenues for future therapies targeting breast cancer

    Association of Alpha B-Crystallin Genotypes with Oral Cancer Susceptibility, Survival, and Recurrence in Taiwan

    Get PDF
    BACKGROUND: Alpha B-crystallin (CRYAB) is a protein that functions as "molecular chaperone" in preserving intracellular architecture and cell membrane. Also, CRYAB is highly antiapoptotic. Abnormal CRYAB expression is a prognostic biomarker for oral cancer, while its genomic variations and the association with carcinogenesis have never been studied. METHODOLOGY/FINDING: Therefore, we hypothesized that CRYAB single nucleotide polymorphisms may be associated with oral cancer risk. In this hospital-based study, the association of CRYAB A-1215G (rs2228387), C-802G (rs14133) and intron2 (rs2070894) polymorphisms with oral cancer in a Taiwan population was investigated. In total, 496 oral cancer patients and 992 age- and gender-matched healthy controls were genotyped and analyzed. A significantly different frequency distribution was found in CRYAB C-802G genotypes, but not in A-1215G and intron2 genotypes, between the oral cancer and control groups. The CRYAB C-802G G allele conferred an increased risk of oral cancer (P = 1.49×10(-5)). Patients carrying CG/GG at CRYAB C-802G were of lower 5-year survival and higher recurrence rate than those of CC (P<0.05). CONCLUSION/SIGNIFICANCE: Our results provide the first evidence that the G allele of CRYAB C-802G is correlated with oral cancer risk and this polymorphism may be a useful marker for oral cancer recurrence and survival prediction for clinical reference

    Prior EGFR tyrosine-kinase inhibitor therapy did not influence the efficacy of subsequent pemetrexed plus platinum in advanced chemona&amp;iuml;ve patients with EGFR-mutant lung adenocarcinoma

    Get PDF
    BACKGROUND: Tumor cells before and after epidermal growth-factor receptor (EGFR) tyrosine-kinase inhibitor (TKI) therapy might display different characteristics. The aim of this study was to evaluate the influence of prior EGFR TKI therapy on the efficacy of subsequent pemetrexed plus platinum (PP) in advanced chemonaïve patients with EGFR-mutant lung adenocarcinoma. MATERIALS AND METHODS: Advanced chemonaïve patients with EGFR-mutant lung adenocarcinoma receiving PP as first-line chemotherapy were enrolled retrospectively in two medical centers of Taiwan. The objective of this study was to compare objective response rate (ORR), disease-control rates (DCR), progression-free survival (PFS), and overall survival (OS) of PP in patients with and without prior EGFR TKI therapy. RESULTS: In total, 105 patients were analyzed. Sixty-one patients (58.1%) had prior EGFR TKI therapy and used PP as second-line treatment. The other 44 patients (41.9%) received PP as first-line therapy. ORRs of PP in patients with and without prior EGFR TKI therapy were 24.6% and 38.6%, respectively (P=0.138). DCRs of the two groups were 62.3% and 65.9%, respectively (P=0.837). The median PFS (6.1 versus 6.1 months, P=0.639) and OS (34.4 versus 32.3 months, P=0.394) were comparable between the groups with and without prior EGFR TKI therapy. In a subgroup analysis of patients with prior EGFR TKI therapy, there was no significant association between the efficacy of first-line EGFR TKI and the outcome of subsequent PP therapy. CONCLUSION: Our results suggested that prior EGFR TKI therapy would not influence the efficacy of subsequent PP therapy in advanced chemonaïve patients with EGFR-mutant lung adenocarcinoma
    corecore