Oncolytic Activity of Avian Influenza Virus in Human Pancreatic Ductal Adenocarcinoma Cell Lines
Pizzuto, Matteo S.; Silic-Benussi, Micol; Pavone, Silvia; Ciminale, Vincenzo; Capua, Ilaria
2014-01-01
ABSTRACT Pancreatic ductal adenocarcinoma (PDA) is the most lethal form of human cancer, with dismal survival rates due to late-stage diagnoses and a lack of efficacious therapies. Building on the observation that avian influenza A viruses (IAVs) have a tropism for the pancreas in vivo, the present study was aimed at testing the efficacy of IAVs as oncolytic agents for killing human PDA cell lines. Receptor characterization confirmed that human PDA cell lines express the alpha-2,3- and the alpha-2,6-linked glycan receptor for avian and human IAVs, respectively. PDA cell lines were sensitive to infection by human and avian IAV isolates, which is consistent with this finding. Growth kinetic experiments showed preferential virus replication in PDA cells over that in a nontransformed pancreatic ductal cell line. Finally, at early time points posttreatment, infection with IAVs caused higher levels of apoptosis in PDA cells than gemcitabine and cisplatin, which are the cornerstone of current therapies for PDA. In the BxPC-3 PDA cell line, apoptosis resulted from the engagement of the intrinsic mitochondrial pathway. Importantly, IAVs did not induce apoptosis in nontransformed pancreatic ductal HPDE6 cells. Using a model based on the growth of a PDA cell line as a xenograft in SCID mice, we also show that a slightly pathogenic avian IAV significantly inhibited tumor growth following intratumoral injection. Taken together, these results are the first to suggest that IAVs may hold promise as future agents of oncolytic virotherapy against pancreatic ductal adenocarcinomas. IMPORTANCE Despite intensive studies aimed at designing new therapeutic approaches, PDA still retains the most dismal prognosis among human cancers. In the present study, we provide the first evidence indicating that avian IAVs of low pathogenicity display a tropism for human PDA cells, resulting in viral RNA replication and a potent induction of apoptosis in vitro and antitumor effects in vivo. These results suggest that slightly pathogenic IAVs may prove to be effective for oncolytic virotherapy of PDA and provide grounds for further studies to develop specific and targeted viruses, with the aim of testing their efficacy in clinical contexts. PMID:24899201
Chou, Angela; Froio, Danielle; Nagrial, Adnan M; Parkin, Ashleigh; Murphy, Kendelle J; Chin, Venessa T; Wohl, Dalia; Steinmann, Angela; Stark, Rhys; Drury, Alison; Walters, Stacey N; Vennin, Claire; Burgess, Andrew; Pinese, Mark; Chantrill, Lorraine A; Cowley, Mark J; Molloy, Timothy J; Waddell, Nicola; Johns, Amber; Grimmond, Sean M; Chang, David K; Biankin, Andrew V; Sansom, Owen J; Morton, Jennifer P; Grey, Shane T; Cox, Thomas R; Turchini, John; Samra, Jaswinder; Clarke, Stephen J; Timpson, Paul; Gill, Anthony J; Pajic, Marina
2017-10-28
Extensive molecular heterogeneity of pancreatic ductal adenocarcinoma (PDA), few effective therapies and high mortality make this disease a prime model for advancing development of tailored therapies. The p16-cyclin D-cyclin-dependent kinase 4/6-retinoblastoma (RB) protein (CDK4) pathway, regulator of cell proliferation, is deregulated in PDA. Our aim was to develop a novel personalised treatment strategy for PDA based on targeting CDK4. Sensitivity to potent CDK4/6 inhibitor PD-0332991 (palbociclib) was correlated to protein and genomic data in 19 primary patient-derived PDA lines to identify biomarkers of response. In vivo efficacy of PD-0332991 and combination therapies was determined in subcutaneous, intrasplenic and orthotopic tumour models derived from genome-sequenced patient specimens and genetically engineered model. Mechanistically, monotherapy and combination therapy were investigated in the context of tumour cell and extracellular matrix (ECM) signalling. Prognostic relevance of companion biomarker, RB protein, was evaluated and validated in independent PDA patient cohorts (>500 specimens). Subtype-specific in vivo efficacy of PD-0332991-based therapy was for the first time observed at multiple stages of PDA progression: primary tumour growth, recurrence (second-line therapy) and metastatic setting and may potentially be guided by a simple biomarker (RB protein). PD-0332991 significantly disrupted surrounding ECM organisation, leading to increased quiescence, apoptosis, improved chemosensitivity, decreased invasion, metastatic spread and PDA progression in vivo. RB protein is prevalent in primary operable and metastatic PDA and may present a promising predictive biomarker to guide this therapeutic approach. This study demonstrates the promise of CDK4 inhibition in PDA over standard therapy when applied in a molecular subtype-specific context. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Selective impact of CDK4/6 suppression on patient-derived models of pancreatic cancer.
Witkiewicz, Agnieszka K; Borja, Nicholas A; Franco, Jorge; Brody, Jonathan R; Yeo, Charles J; Mansour, John; Choti, Michael A; McCue, Peter; Knudsen, Erik S
2015-06-30
Pancreatic ductal adenocarcinoma (PDA) harbors an exceedingly poor prognosis, and is generally considered a therapy-recalcitrant disease due to poor response to conventional chemotherapy coupled with non-actionable genetic drivers (e.g. KRAS mutations). However, PDA frequently loses p16ink4a, thereby leading to deregulation of CDK4/6. Surprisingly, in established cell models and xenografts, CDK4/6 inhibition has a modest effect on proliferation and resistance develops rapidly. To determine if such weak response was an intrinsic feature of PDA, we developed primary tumor explants that maintain the tumor environment and recapitulate feuture of primary PDA. The CDK4/6 inhibitor PD-0332991 was highly efficient at suppressing proliferation in 14 of the 15 explants. In the single resistant explant, we identified the rare loss of the RB tumor suppressor as the basis for resistance. Patient-derived xenografts (PDXs) were developed in parallel, and unlike the xenografts emerging from established cell lines, the PDXs maintained the histoarchitecture of the primary tumor. These PDXs were highly sensitive to CDK4/6 inhibition, yielding a complete suppression of PDA proliferation. Together, these data indicate that primary PDA is sensitive to CDK4/6 inhibition, that specific biomarkers can delineate intrinsic resistance, and that established cell line models may not represent an adequate means for evaluating therapeutic sensitivities.
Gong, Qiaoke; Davis, Molly; Chipitsyna, Galina; Yeo, Charles J; Arafat, Hwyda A
2010-07-01
Pancreatic ductal adenocarcinoma (PDA) is an aggressive malignancy with an annual mortality rate close to its annual incidence. We recently demonstrated that angiotensin II (AngII) type 1 receptor (AT1R) might be involved in PDA angiogenesis. This study evaluated the antiproliferative and proapoptotic effects of an AT1R blocker, losartan, in PDA cells with different p53 mutation status. Cell cycle was analyzed by flow cytometric analysis of DNA content; apoptosis by annexin V-fluorescein isothiocyanate (V-FITC) and terminal deoxytransferase (TdT)-mediated dUTP nick-end labeling staining; messenger RNA and protein by real-time polymerase chain reaction and Western blotting; caspase-3 activity by colorimetric assay; and promoter activity by luciferase assay. Losartan dose-dependently decreased cell survival and increased their preG1 accumulation. It also increased p53, p21, p27, and Bax and reduced Bcl-2 and Bcl-xl expression. In wtp53 cells, losartan increased p53 transcription and activated caspase-3 in both cell lines. However, its proapoptotic effects in mtp53 cells were mainly caspase-3-dependent. Our data describe the involvement of AT1R in PDA cell apoptotic machinery and provide the first evidences that losartan stimulates the proapoptotic signaling pathways regardless of the p53 mutation status. As loss of p53 function is frequently observed in PDA patients, our data suggest AT1R blockade as a novel therapeutic strategy to control PDA growth.
Wei, Yi; Gao, Li; Wang, Lu; Shi, Lin; Wei, Erdong; Zhou, Baotong; Zhou, Li; Ge, Bo
2017-11-01
We reported a simple polydopamine (PDA)-based surface modification method to prepare novel targeted doxorubicin-loaded mesoporous silica nanoparticles and peptide CSNRDARRC conjugation (DOX-loaded MSNs@PDA-PEP) for enhancing the therapeutic effects on bladder cancer. Drug-loaded NPs were characterized in terms of size, size distribution, zeta potential, transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area and drug loading content. In vitro drug release indicated that DOX-loaded MSNs@PDA and MSNs@PDA-PEP had similar release kinetic profiles of DOX. The PDA coating well controlled DOX release and was highly sensitive to pH value. Confocal laser scanning microscopy (CLSM) showed that drug-loaded MSNs could be internalized by human bladder cancer cell line HT-1376, and DOX-loaded MSNs@PDA-PEP had the highest cellular uptake efficiency due to ligand-receptor recognition. The antitumor effects of DOX-loaded nanoparticles were evaluated by the MTT assay in vitro and by a xenograft tumor model in vivo, demonstrating that targeted nanocarriers DOX-loaded MSNs@PDA-PEP were significantly superior to free DOX and DOX-loaded MSNs@PDA. The novel DOX-loaded MSNs@PDA-PEP, which specifically recognized HT-1376 cells, can be used as a potential targeted drug delivery system for bladder cancer therapy.
Genotyping and expression analysis of IDO2 in human pancreatic cancer: a novel, active target
Witkiewicz, Agnieszka K.; Costantino, Christina L.; Metz, Richard; Muller, Alexander J.; Prendergast, George C.; Yeo, Charles J.; Brody, Jonathan R.
2011-01-01
Background We recently discovered that the enzyme indoleamine 2,3-dioxygenase (IDO) is overexpressed in primary pancreatic ductal adenocarcinomas (PDA) and in lymph node metastases (J Am Coll Surg. 5:849-54: 2008). IDO2 is a recently discovered relative of IDO that has unique signaling properties (Cancer Res. 67:7082-7087: 2007). Notably, the IDO2 gene has two functional polymorphisms commonly found in human populations that abolish its enzymatic activity (R235W and Y359STOP). Both IDO and IDO2 repress the immune system and we hypothesize that expression of these enzymes in PDA may help cancer cells evade immune detection. Methods Based on evidence that the IDO2 may be a preferential target of D-1-methyl-tryptophan (1-MT), a clinical lead inhibitor of IDO currently being evaluated in Phase I trials, we sequenced IDO2 in 36 resected PDAs and evaluated its expression in relation to the two known genetic polymorphisms. Results In our patient cohort, we found that 58% (21/36) of the cases were heterozygous for the R235W polymorphism; 28% (10/36) were homozygous wild-type; and only 14% (5/36) were homozygous for the functionally inactive polymorphism. Interestingly, IDO2 had a homozygous wild-type configuration in two pancreatic cancer cell lines whereas one cell line (MiaPaCa2 cells) was homozygous for the R235W polymorphism. As for the Y359STOP polymorphism (seen in the cell line Hs766T), we found that 27% (10/36) of the cases were heterozygous, 62% (22/36) were homozygous wild-type, and only 11% (4/36) were homozygous for this functionally inactive allele. Ruling out the possibility of compound polymorphic variants, we estimated 75% of our resected patient cohort had an active IDO2 enzyme with a conservative estimate that 58% of the patients had at least one functional allele. In immunohistochemical analyses, we found that IDO2 was equally overexpressed in pancreatic cancer tissue from each genetially polymorphic subgroup. We also detected IDO2 protein expression in the genetically distinct pancreatic cancer cell lines after exposure with IFN-γ, establishing that even functionally polymorphic IDO2 sequences can generate IDO2 protein. Conclusions These are the first data to report IDO2 expression in PDA and indicate that IDO2 genetic polymorphisms do not negate IFN-γ-inducible protein expression. IDO2 genotyping and expression analysis of our PDA patient tissue bank and cell lines show that IDO2 is active and expressed in a majority of PDA patients. Taken together, these data strongly suggest that the clinical lead compound D-1-MT acting through IDO2 might be useful in treatment of PDA, either alone or in combination with other anti-tumor modalities. PMID:19476837
Bi, Jiangang; Zeng, Xiaowei; Mei, Lin; Bao, Shiyun; He, Lisheng; Shan, Aijun; Zhang, Yue; Yu, Xiaofang
2018-01-01
Introduction MicroRNA-155 (miR-155) is an oncogenic microRNA, which is upregulated in many human cancers including colorectal cancer (CRC). Overexpression of miR-155 has been found to regulate several cancer-related pathways, and therefore, targeting miR-155 may be an effective strategy for cancer therapy. However, effective and safe delivery of anti-miR-155 to tumors remains challenging for the clinical applications of anti-miR-155-based therapeutics. Methods In this study, we explored the expression of miR-155 and the transcription factor nuclear factor kappa B (NF-κB) in CRC tissues and cell lines, and the possible relationship between miR-155 and NF-κB. We further report on anti-miR-155-loaded mesoporous silica nanoparticles (MSNs) modified with polymerized dopamine (PDA) and AS1411 aptamer (MSNs-anti-miR-155@PDA-Apt) for the targeted treatment of CRC. Results Results showed that miR-155 is overexpressed in CRC tissues and cell lines, and there is a positive feedback loop between NF-κB and miR-155. Compared to the control groups, MSNs-anti-miR-155@PDA-Apt could efficiently downregulate miR-155 expression in SW480 cells and achieve significantly high targeting efficiency and enhanced therapeutic effects in both in vivo and in vitro experiments. Furthermore, inhibition of miR-155 by MSNs-anti-miR-155@PDA-Apt can enhance the sensitivity of SW480 to 5-fluorouracil chemotherapy. Conclusion Thus, our results suggested that MSNs-anti-miR-155@PDA-Apt is a promising nanoformulation for CRC treatment. PMID:29535520
Zhang, Yiyao; Liu, Li; Fan, Pei; Bauer, Nathalie; Gladkich, Jury; Ryschich, Eduard; Bazhin, Alexandr V.; Giese, Nathalia A.; Strobel, Oliver; Hackert, Thilo; Hinz, Ulf; Gross, Wolfgang; Fortunato, Franco; Herr, Ingrid
2015-01-01
Pancreatic ductal adenocarcinoma (PDA) is characterized by an extremely poor prognosis. An inflammatory microenvironment triggers the pronounced desmoplasia, the selection of cancer stem-like cells (CSCs) and therapy resistance. The anti-inflammatory drug aspirin is suggested to lower the risk for PDA and to improve the treatment, although available results are conflicting and the effect of aspirin to CSC characteristics and desmoplasia in PDA has not yet been investigated. We characterized the influence of aspirin on CSC features, stromal reactions and gemcitabine resistance. Four established and 3 primary PDA cell lines, non-malignant cells, 3 patient tumor-derived CSC-enriched spheroidal cultures and tissues from patients who did or did not receive aspirin before surgery were analyzed using MTT assays, flow cytometry, colony and spheroid formation assays, Western blot analysis, antibody protein arrays, electrophoretic mobility shift assays (EMSAs), immunohistochemistry and in vivo xenotransplantation. Aspirin significantly induced apoptosis and reduced the viability, self-renewal potential, and expression of proteins involved in inflammation and stem cell signaling. Aspirin also reduced the growth and invasion of tumors in vivo, and it significantly prolonged the survival of mice with orthotopic pancreatic xenografts in combination with gemcitabine. This was associated with a decreased expression of markers for progression, inflammation and desmoplasia. These findings were confirmed in tissue samples obtained from patients who had or had not taken aspirin before surgery. Importantly, aspirin sensitized cells that were resistant to gemcitabine and thereby enhanced the therapeutic efficacy. Aspirin showed no obvious toxic effects on normal cells, chick embryos or mice. These results highlight aspirin as an effective, inexpensive and well-tolerated co-treatment to target inflammation, desmoplasia and CSC features PDA. PMID:25846752
Kinsey, Conan; Balakrishnan, Vijaya; O’Dell, Michael R.; Huang, Jing Li; Newman, Laurel; Whitney-Miller, Christa L.; Hezel, Aram F.; Land, Hartmut
2014-01-01
Summary Mutations in p53 and RAS potently cooperate in oncogenic transformation and correspondingly these genetic alterations frequently coexist in pancreatic ductal adenocarcinoma (PDA) and other human cancers. Previously we identified a set of genes synergistically activated by combined RAS and p53 mutations as frequent downstream mediators of tumorigenesis. Here, we show that the synergistically activated gene Plac8 is critical for pancreatic cancer growth. Silencing of Plac8 in cell lines suppresses tumor formation by blocking autophagy, a process essential for maintaining metabolic homeostasis in PDA, and genetic inactivation in an engineered mouse model inhibits PDA progression. We show that Plac8 is a critical regulator of the autophagic machinery, localizing to the lysosomal compartment and facilitating lysosome-autophagosome fusion. Plac8 thus provides a mechanistic link between primary oncogenic mutations and the induction of autophagy, a central mechanism of metabolic reprogramming, during PDA progression. PMID:24794439
Towards an optimal treatment algorithm for metastatic pancreatic ductal adenocarcinoma (PDA)
Uccello, M.; Moschetta, M.; Mak, G.; Alam, T.; Henriquez, C. Murias; Arkenau, H.-T.
2018-01-01
Chemotherapy remains the mainstay of treatment for advanced pancreatic ductal adenocarcinoma (pda). Two randomized trials have demonstrated superiority of the combination regimens folfirinox (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) and gemcitabine plus nab-paclitaxel over gemcitabine monotherapy as a first-line treatment in adequately fit subjects. Selected pda patients progressing to first-line therapy can receive secondline treatment with moderate clinical benefit. Nevertheless, the optimal algorithm and the role of combination therapy in second-line are still unclear. Published second-line pda clinical trials enrolled patients progressing to gemcitabine-based therapies in use before the approval of nab-paclitaxel and folfirinox. The evolving scenario in second-line may affect the choice of the first-line treatment. For example, nanoliposomal irinotecan plus 5-fluouracil and leucovorin is a novel second-line option which will be suitable only for patients progressing to gemcitabine-based therapy. Therefore, clinical judgement and appropriate patient selection remain key elements in treatment decision. In this review, we aim to illustrate currently available options and define a possible algorithm to guide treatment choice. Future clinical trials taking into account sequential treatment as a new paradigm in pda will help define a standard algorithm. PMID:29507500
Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C.; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank; Bazhin, Alexandr V.; Herr, Ingrid
2014-01-01
According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patient-tumor-derived CSC-enriched spheroidal cultures were analyzed by glucose turnover measurements, MTT and ATP assays, flow cytometry of ALDH1 activity and annexin positivity, colony and spheroid formation, western blotting, electrophoretic mobility shift assay, xenotransplantation, and immunohistochemistry. The effect of siRNA-mediated inhibition of LDH-A and LDH-B was also investigated. The PDA cells exhibited a high glucose metabolism, and glucose withdrawal or LDH inhibition by siRNA prevented growth and colony formation. Treatment with the anti-glycolytic agent 3-bromopyruvate almost completely blocked cell viability, self-renewal potential, NF-κB binding activity, and stem cell-related signaling and reverted gemcitabine resistance. 3-bromopyruvate was less effective in weakly malignant PDA cells and did not affect non-malignant cells, predicting minimal side effects. 3-bromopyruvate inhibited in vivo tumor engraftment and growth on chicken eggs and mice and enhanced the efficacy of gemcitabine by influencing the expression of markers of proliferation, apoptosis, self-renewal, and metastasis. Most importantly, primary CSC-enriched spheroidal cultures were eliminated by 3-bromopyruvate. These findings propose that CSCs may be specifically dependent on a high glucose turnover and suggest 3-bromopyruvate for therapeutic intervention. PMID:25015789
Isayev, Orkhan; Rausch, Vanessa; Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank; Bazhin, Alexandr V; Herr, Ingrid
2014-07-15
According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patient-tumor-derived CSC-enriched spheroidal cultures were analyzed by glucose turnover measurements, MTT and ATP assays, flow cytometry of ALDH1 activity and annexin positivity, colony and spheroid formation, western blotting, electrophoretic mobility shift assay, xenotransplantation, and immunohistochemistry. The effect of siRNA-mediated inhibition of LDH-A and LDH-B was also investigated. The PDA cells exhibited a high glucose metabolism, and glucose withdrawal or LDH inhibition by siRNA prevented growth and colony formation. Treatment with the anti-glycolytic agent 3-bromopyruvate almost completely blocked cell viability, self-renewal potential, NF-κB binding activity, and stem cell-related signaling and reverted gemcitabine resistance. 3-bromopyruvate was less effective in weakly malignant PDA cells and did not affect non-malignant cells, predicting minimal side effects. 3-bromopyruvate inhibited in vivo tumor engraftment and growth on chicken eggs and mice and enhanced the efficacy of gemcitabine by influencing the expression of markers of proliferation, apoptosis, self-renewal, and metastasis. Most importantly, primary CSC-enriched spheroidal cultures were eliminated by 3-bromopyruvate. These findings propose that CSCs may be specifically dependent on a high glucose turnover and suggest 3-bromopyruvate for therapeutic intervention.
Li, Chung-Pin; Buza, Elizabeth L.; Blomberg, Rachel; Govindaraju, Priya; Avery, Diana; Monslow, James; Hsiao, Michael
2017-01-01
Pancreatic ductal adenocarcinomas (PDAs) are desmoplastic and can undergo epithelial-to-mesenchymal transition to confer metastasis and chemoresistance. Studies have demonstrated that phenotypically and functionally distinct stromal cell populations exist in PDAs. Fibroblast activation protein–expressing (FAP-expressing) cells act to enhance PDA progression, while α–smooth muscle actin myofibroblasts can restrain PDA. Thus, identification of precise molecular targets that mediate the protumorigenic activity of FAP+ cells will guide development of therapy for PDA. Herein, we demonstrate that FAP overexpression in the tumor microenvironment correlates with poor overall and disease-free survival of PDA patients. Genetic deletion of FAP delayed onset of primary tumor and prolonged survival of mice in the KPC mouse model of PDA. While genetic deletion of FAP did not affect primary tumor weight in advanced disease, FAP deficiency increased tumor necrosis and impeded metastasis to multiple organs. Lineage-tracing studies unexpectedly showed that FAP is not only expressed by stromal cells, but can also be detected in a subset of CD90+ mesenchymal PDA cells, representing up to 20% of total intratumoral FAP+ cells. These data suggest that FAP may regulate PDA progression and metastasis in cell-autonomous and/or non-cell-autonomous fashions. Together, these data support pursuing FAP as a therapeutic target in PDA. PMID:28978805
Kajihara, Mikio; Takakura, Kazuki; Kanai, Tomoya; Ito, Zensho; Matsumoto, Yoshihiro; Shimodaira, Shigetaka; Okamoto, Masato; Ohkusa, Toshifumi; Koido, Shigeo
2016-05-14
The incidence of pancreatic ductal adenocarcinoma (PDA) is on the rise, and the prognosis is extremely poor because PDA is highly aggressive and notoriously difficult to treat. Although gemcitabine- or 5-fluorouracil-based chemotherapy is typically offered as a standard of care, most patients do not survive longer than 1 year. Therefore, the development of alternative therapeutic approaches for patients with PDA is imperative. As PDA cells express numerous tumor-associated antigens that are suitable vaccine targets, one promising treatment approach is cancer vaccines. During the last few decades, cell-based cancer vaccines have offered encouraging results in preclinical studies. Cell-based cancer vaccines are mainly generated by presenting whole tumor cells or dendritic cells to cells of the immune system. In particular, several clinical trials have explored cell-based cancer vaccines as a promising therapeutic approach for patients with PDA. Moreover, chemotherapy and cancer vaccines can synergize to result in increased efficacies in patients with PDA. In this review, we will discuss both the effect of cell-based cancer vaccines and advances in terms of future strategies of cancer vaccines for the treatment of PDA patients.
Leca, Julie; Martinez, Sébastien; Lac, Sophie; Nigri, Jérémy; Secq, Véronique; Rubis, Marion; Bressy, Christian; Lavaut, Marie-Noelle; Dusetti, Nelson; Loncle, Céline; Roques, Julie; Pietrasz, Daniel; Bousquet, Corinne; Garcia, Stéphane; Granjeaud, Samuel; Ouaissi, Mehdi; Bachet, Jean Baptiste; Iovanna, Juan L.; Zimmermann, Pascale; Vasseur, Sophie
2016-01-01
The intratumoral microenvironment, or stroma, is of major importance in the pathobiology of pancreatic ductal adenocarcinoma (PDA), and specific conditions in the stroma may promote increased cancer aggressiveness. We hypothesized that this heterogeneous and evolving compartment drastically influences tumor cell abilities, which in turn influences PDA aggressiveness through crosstalk that is mediated by extracellular vesicles (EVs). Here, we have analyzed the PDA proteomic stromal signature and identified a contribution of the annexin A6/LDL receptor-related protein 1/thrombospondin 1 (ANXA6/LRP1/TSP1) complex in tumor cell crosstalk. Formation of the ANXA6/LRP1/TSP1 complex was restricted to cancer-associated fibroblasts (CAFs) and required physiopathologic culture conditions that improved tumor cell survival and migration. Increased PDA aggressiveness was dependent on tumor cell–mediated uptake of CAF-derived ANXA6+ EVs carrying the ANXA6/LRP1/TSP1 complex. Depletion of ANXA6 in CAFs impaired complex formation and subsequently impaired PDA and metastasis occurrence, while injection of CAF-derived ANXA6+ EVs enhanced tumorigenesis. We found that the presence of ANXA6+ EVs in serum was restricted to PDA patients and represents a potential biomarker for PDA grade. These findings suggest that CAF–tumor cell crosstalk supported by ANXA6+ EVs is predictive of PDA aggressiveness, highlighting a therapeutic target and potential biomarker for PDA. PMID:27701147
Engineering fluorescent poly(dopamine) capsules.
Chen, Xi; Yan, Yan; Müllner, Markus; van Koeverden, Martin P; Noi, Ka Fung; Zhu, Wei; Caruso, Frank
2014-03-18
The recent development of poly(dopamine) (PDA) capsules provides new opportunities for their application in biology and medicine. To advance the biomedical application of PDA capsules, strategies that enable the preparation of fluorescently labeled PDA (F-PDA) capsules are required, as this will allow evaluation of their cellular interactions using a range of fluorescence-based techniques. Herein, we report a facile approach for the fabrication of F-PDA capsules via the polymerization of dopamine (DA) on sacrificial templates in the presence of hydrogen peroxide (H2O2). F-PDA capsules with well-defined sizes are prepared by templating different organic and inorganic particles. The resulting F-PDA capsules show negligible cytotoxicity in HeLa cells after incubation for 48 h. We also demonstrate visualization of the F-PDA capsules following internalization by HeLa cells using conventional fluorescence microscopy, en route toward detailed investigations on their biological interactions.
γδ T Cells Support Pancreatic Oncogenesis by Restraining αβ T Cell Activation.
Daley, Donnele; Zambirinis, Constantinos Pantelis; Seifert, Lena; Akkad, Neha; Mohan, Navyatha; Werba, Gregor; Barilla, Rocky; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu Raj Kumar; Avanzi, Antonina; Tippens, Daniel; Narayanan, Rajkishen; Jang, Jung-Eun; Newman, Elliot; Pillarisetty, Venu Gopal; Dustin, Michael Loran; Bar-Sagi, Dafna; Hajdu, Cristina; Miller, George
2016-09-08
Inflammation is paramount in pancreatic oncogenesis. We identified a uniquely activated γδT cell population, which constituted ∼40% of tumor-infiltrating T cells in human pancreatic ductal adenocarcinoma (PDA). Recruitment and activation of γδT cells was contingent on diverse chemokine signals. Deletion, depletion, or blockade of γδT cell recruitment was protective against PDA and resulted in increased infiltration, activation, and Th1 polarization of αβT cells. Although αβT cells were dispensable to outcome in PDA, they became indispensable mediators of tumor protection upon γδT cell ablation. PDA-infiltrating γδT cells expressed high levels of exhaustion ligands and thereby negated adaptive anti-tumor immunity. Blockade of PD-L1 in γδT cells enhanced CD4(+) and CD8(+) T cell infiltration and immunogenicity and induced tumor protection suggesting that γδT cells are critical sources of immune-suppressive checkpoint ligands in PDA. We describe γδT cells as central regulators of effector T cell activation in cancer via novel cross-talk. Copyright © 2016 Elsevier Inc. All rights reserved.
NLRP3 signaling drives macrophage-induced adaptive immune suppression in pancreatic carcinoma
Daley, Donnele; Mani, Vishnu R.; Mohan, Navyatha; Akkad, Neha; Savadkar, Shivraj; Lee, Ki Buom; Torres-Hernandez, Alejandro; Aykut, Berk; Diskin, Brian; Wang, Wei; Farooq, Mohammad S.; Mahmud, Arif I.; Werba, Gregor; Morales, Eduardo J.; Lall, Sarah; Rubin, Amanda G.; Berman, Matthew E.; Hundeyin, Mautin
2017-01-01
The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDA) is characterized by immune tolerance, which enables disease to progress unabated by adaptive immunity. However, the drivers of this tolerogenic program are incompletely defined. In this study, we found that NLRP3 promotes expansion of immune-suppressive macrophages in PDA. NLRP3 signaling in macrophages drives the differentiation of CD4+ T cells into tumor-promoting T helper type 2 cell (Th2 cell), Th17 cell, and regulatory T cell populations while suppressing Th1 cell polarization and cytotoxic CD8+ T cell activation. The suppressive effects of NLRP3 signaling were IL-10 dependent. Pharmacological inhibition or deletion of NLRP3, ASC (apoptosis-associated speck-like protein containing a CARD complex), or caspase-1 protected against PDA and was associated with immunogenic reprogramming of innate and adaptive immunity within the TME. Similarly, transfer of PDA-entrained macrophages or T cells from NLRP3−/− hosts was protective. These data suggest that targeting NLRP3 holds the promise for the immunotherapy of PDA. PMID:28442553
Poly(dopamine) coating of 3D printed poly(lactic acid) scaffolds for bone tissue engineering.
Kao, Chia-Tze; Lin, Chi-Chang; Chen, Yi-Wen; Yeh, Chia-Hung; Fang, Hsin-Yuan; Shie, Ming-You
2015-11-01
3D printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating to regulate cell adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared PLA 3D scaffolds coated with polydopamine (PDA). The chemical composition and surface properties of PDA/PLA were characterized by XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation, and cell cycle of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. In addition, the collagen I secreted from cells was increased and promoted cell attachment and cell cycle progression were depended on the PDA content. In osteogenesis assay, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on pure PLA scaffolds. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hADSCs. Copyright © 2015 Elsevier B.V. All rights reserved.
Lee, Hye-Young; Jeong, Young-Il; Choi, Ki-Choon
2011-01-01
p-Phenylenediamine (PDA) or its related chemicals are used more extensively than oxidative hair dyes. However, permanent hair dyes such as PDA are known to have potent contact allergy reactions in humans, and severe allergic reactions are problematic. PDA-incorporated nanoparticles were prepared based on ion-complex formation between the cationic groups of PDA and the anionic groups of poly(γ-glutamic acid) (PGA). To reinforce PDA/PGA ion complexes, glycol chitosan (GC) was added. PDA-incorporated nanoparticles were characterized using field-emission scanning electron microscopy, Fourier- transform infrared (FT-IR) spectroscopy, dynamic light scattering, and powder X-ray diffractometry (XRD). Nanoparticles were formed by ion-complex formation between the amine groups of PDA and the carboxyl groups of PGA. PDA-incorporated nanoparticles are small in size (<100 nm), and morphological observations showed spherical shapes. FT-IR spectra results showed that the carboxylic acid peak of PGA decreased with increasing PDA content, indicating that the ion complexes were formed between the carboxyl groups of PGA and the amine groups of PDA. Furthermore, the intrinsic peak of the carboxyl groups of PGA was also decreased by the addition of GC. Intrinsic crystalline peaks of PDA were observed by XRD. This crystalline peak of PDA was completely nonexistent when nanoparticles were formed by ion complex between PDA, PGA, and GC, indicating that PDA was complexed with PGA and no free drug existed in the formulation. During the drug-release experiment, an initial burst release of PDA was observed, and then PDA was continuously released over 1 week. Cytotoxicity testing against HaCaT human skin keratinocyte cells showed PDA-incorporated nanoparticles had lower toxicity than PDA itself. Furthermore, PDA-incorporated nanoparticles showed reduced apoptosis and necrosis reaction at HaCaT cells. The authors suggest that these microparticles are ideal candidates for a vehicle for decreasing side effects of hair dye.
Intervention on toll-like receptors in pancreatic cancer.
Vaz, Juan; Andersson, Roland
2014-05-21
Pancreatic ductal adenocarcinoma (PDA) is a devastating disease with pronounced morbidity and a high mortality rate. Currently available treatments lack convincing cost-efficiency determinations and are in most cases not associated with relevant success rate. Experimental stimulation of the immune system in murine PDA models has revealed some promising results. Toll-like receptors (TLRs) are pillars of the immune system that have been linked to several forms of malignancy, including lung, breast and colon cancer. In humans, TLRs are expressed in the pancreatic cancer tissue and in several cancer cell lines, whereas they are not expressed in the normal pancreas. In the present review, we explore the current knowledge concerning the role of different TLRs associated to PDA. Even if almost all known TLRs are expressed in the pancreatic cancer microenvironment, there are only five TLRs suggested as possible therapeutic targets. Most data points at TLR2 and TLR9 as effective tumor markers and agonists could potentially be used as e.g. future adjuvant therapies. The elucidation of the role of TLR3 in PDA is only in its initial phase. The inhibition/blockage of TLR4-related pathways has shown some promising effects, but there are still many steps left before TLR4 inhibitors can be considered as possible therapeutic agents. Finally, TLR7 antagonists seem to be potential candidates for therapy. Independent of their potential in immunotherapies, all existing data indicate that TLRs are strongly involved in the pathophysiology and development of PDA.
CRISPR Knockout of the HuR Gene Causes a Xenograft Lethal Phenotype
Lal, Shruti; Cheung, Edwin C.; Zarei, Mahsa; Preet, Ranjan; Chand, Saswati N.; Mambelli-Lisboa, Nicole C.; Romeo, Carmella; Stout, Matthew C.; Londin, Eric; Goetz, Austin; Lowder, Cinthya Y.; Nevler, Avinoam; Yeo, Charles J.; Campbell, Paul M.; Winter, Jordan M.; Dixon, Dan A.; Brody, Jonathan R.
2017-01-01
Pancreatic ductal adenocarcinoma (PDA) is the third leading cause of cancer related deaths in the U.S., while colorectal cancer (CRC) is the third most common cancer. The RNA binding protein HuR (ELAVL1), supports a pro-oncogenic network in gastrointestinal (GI) cancer cells through enhanced HuR expression. Using a publically available database, HuR expression levels were determined to be increased in primary PDA and CRC tumor cohorts as compared to normal pancreas and colon tissues, respectively. CRISPR/Cas9 technology was successfully used to delete the HuR gene in both PDA (MIA PaCa-2 and Hs 766T) and CRC (HCT116) cell lines. HuR deficiency has a mild phenotype, in vitro, as HuR-deficient MIA PaCa-2 (MIA.HuR-KO(−/−)) cells had increased apoptosis when compared to isogenic wild-type (MIA.HuR-WT(+/+)) cells. Using this isogenic system, mRNAs were identified that specifically bound to HuR and were required for transforming a 2D culture into 3D (i.e., organoids). Importantly, HuR-deficient MIA PaCa-2 and Hs 766T cells were unable to engraft tumors in vivo compared to control HuR-proficient cells, demonstrating a unique xenograft lethal phenotype. While not as a dramatic phenotype, CRISPR knockout HuR HCT116 colon cancer cells (HCT.HuR-KO(−/−)) showed significantly reduced in vivo tumor growth compared to controls (HCT.HuR-WT(+/+)). Finally, HuR deletion affects KRAS activity and controls a subset of pro-oncogenic genes. Implications The work reported here supports the notion that targeting HuR is a promising therapeutic strategy to treat GI malignancies. PMID:28242812
CRISPR Knockout of the HuR Gene Causes a Xenograft Lethal Phenotype.
Lal, Shruti; Cheung, Edwin C; Zarei, Mahsa; Preet, Ranjan; Chand, Saswati N; Mambelli-Lisboa, Nicole C; Romeo, Carmella; Stout, Matthew C; Londin, Eric; Goetz, Austin; Lowder, Cinthya Y; Nevler, Avinoam; Yeo, Charles J; Campbell, Paul M; Winter, Jordan M; Dixon, Dan A; Brody, Jonathan R
2017-06-01
Pancreatic ductal adenocarcinoma (PDA) is the third leading cause of cancer-related deaths in the United States, whereas colorectal cancer is the third most common cancer. The RNA-binding protein HuR (ELAVL1) supports a pro-oncogenic network in gastrointestinal (GI) cancer cells through enhanced HuR expression. Using a publically available database, HuR expression levels were determined to be increased in primary PDA and colorectal cancer tumor cohorts as compared with normal pancreas and colon tissues, respectively. CRISPR/Cas9 technology was successfully used to delete the HuR gene in both PDA (MIA PaCa-2 and Hs 766T) and colorectal cancer (HCT116) cell lines. HuR deficiency has a mild phenotype, in vitro , as HuR-deficient MIA PaCa-2 (MIA.HuR-KO (-/-) ) cells had increased apoptosis when compared with isogenic wild-type (MIA.HuR-WT (+/+) ) cells. Using this isogenic system, mRNAs were identified that specifically bound to HuR and were required for transforming a two-dimensional culture into three dimensional (i.e., organoids). Importantly, HuR-deficient MIA PaCa-2 and Hs 766T cells were unable to engraft tumors in vivo compared with control HuR-proficient cells, demonstrating a unique xenograft lethal phenotype. Although not as a dramatic phenotype, CRISPR knockout HuR HCT116 colon cancer cells (HCT.HuR-KO (-/-) ) showed significantly reduced in vivo tumor growth compared with controls (HCT.HuR-WT (+/+) ). Finally, HuR deletion affects KRAS activity and controls a subset of pro-oncogenic genes. Implications: The work reported here supports the notion that targeting HuR is a promising therapeutic strategy to treat GI malignancies. Mol Cancer Res; 15(6); 696-707. ©2017 AACR . ©2017 American Association for Cancer Research.
Ma, Lina; Liu, Fuyao; Lei, Zhen; Wang, Zhenxin
2017-01-15
Herein, a novel upconversion@polydopamine core@shell nanoparticle (termed as UCNP@PDA NP) -based aptameric biosensor has been fabricated for the quantitative analysis of cytochrome c (Cyt c) inside living cells, which comprises an UCNP@PDA NP, acting as an internal reference and fluorescence quenching agent, and Cy3 modified aptamer enabling ratiometric quantitative Cyt c measurement. After the hybridization of Cy3 labeled aptamer with amino-terminated single DNA on the UCNP@PDA NP surface (termed as UCNP@PDA@AP), the fluorescence of Cy3 can be efficiently quenched by the PDA shell. With the spontaneous cellular uptake of UCNP@PDA@AP, the Cyt c aptamer dissociates from UCNP@PDA NP surface through formation of aptamer-Cyt c complex, resulting in concomitant activation of the Cy3 fluorescence. High amount of Cyt c leads to high fluorescence emission, enabling direct visualization/measurement of the Cyt c by fluorescence microscopy/spectroscopy. The steady upconversion luminescent (UCL) signals can be employed not only for intracellular imaging, but also as an internal reference for evaluating intracellular Cyt c amount using the ratio of fluorescence intensity of Cy3 with the UCL intensity of UCNP. The UCNP@PDA@AP shows a reasonable detection limit (20nM) and large dynamic range (50nM to 10μM, which covers the literature reported values (1-10μM) for cytosolic Cyt c in apoptotic cells) for detecting Cyt c in buffer with excellent selectivity. In addition, the UCNP@PDA@AP has been successfully used to monitor etoposide induced intracellular releasing of Cyt c, providing the possibility for cell-based screening of apoptosis-inducing drugs. Copyright © 2016 Elsevier B.V. All rights reserved.
Céspedes, María Virtudes; Guillén, María José; López-Casas, Pedro Pablo; Sarno, Francesca; Gallardo, Alberto; Álamo, Patricia; Cuevas, Carmen; Hidalgo, Manuel; Galmarini, Carlos María; Allavena, Paola; Avilés, Pablo; Mangues, Ramón
2016-01-01
ABSTRACT We explored whether the combination of lurbinectedin (PM01183) with the antimetabolite gemcitabine could result in a synergistic antitumor effect in pancreatic ductal adenocarcinoma (PDA) mouse models. We also studied the contribution of lurbinectedin to this synergism. This drug presents a dual pharmacological effect that contributes to its in vivo antitumor activity: (i) specific binding to DNA minor grooves, inhibiting active transcription and DNA repair; and (ii) specific depletion of tumor-associated macrophages (TAMs). We evaluated the in vivo antitumor activity of lurbinectedin and gemcitabine as single agents and in combination in SW-1990 and MIA PaCa-2 cell-line xenografts and in patient-derived PDA models (AVATAR). Lurbinectedin-gemcitabine combination induced a synergistic effect on both MIA PaCa-2 [combination index (CI)=0.66] and SW-1990 (CI=0.80) tumor xenografts. It also induced complete tumor remissions in four out of six patient-derived PDA xenografts. This synergism was associated with enhanced DNA damage (anti-γ-H2AX), cell cycle blockage, caspase-3 activation and apoptosis. In addition to the enhanced DNA damage, which is a consequence of the interaction of the two drugs with the DNA, lurbinectedin induced TAM depletion leading to cytidine deaminase (CDA) downregulation in PDA tumors. This effect could, in turn, induce an increase of gemcitabine-mediated DNA damage that was especially relevant in high-density TAM tumors. These results show that lurbinectedin can be used to develop ‘molecularly targeted’ combination strategies. PMID:27780828
Yeh, Chia-Hung; Chen, Yi-Wen; Shie, Ming-You; Fang, Hsin-Yuan
2015-07-14
Three-dimensional printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating and Xu Duan (XD) immobilization to regulate cell adhesion, proliferation and differentiation of human bone-marrow mesenchymal stem cells (hBMSCs). We prepared PLA scaffolds and coated with polydopamine (PDA). The chemical composition and surface properties of PLA/PDA/XD were characterized by XPS. PLA/PDA/XD controlled hBMSCs' responses in several ways. Firstly, adhesion and proliferation of hBMSCs cultured on PLA/PDA/XD were significantly enhanced relative to those on PLA. In addition, the focal adhesion kinase (FAK) expression of cells was increased and promoted cell attachment depended on the XD content. In osteogenesis assay, the osteogenesis markers of hBMSCs cultured on PLA/PDA/XD were significantly higher than seen in those cultured on a pure PLA/PDA scaffolds. Moreover, hBMSCs cultured on PLA/PDA/XD showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hBMSCs.
Yeh, Chia-Hung; Chen, Yi-Wen; Shie, Ming-You; Fang, Hsin-Yuan
2015-01-01
Three-dimensional printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating and Xu Duan (XD) immobilization to regulate cell adhesion, proliferation and differentiation of human bone-marrow mesenchymal stem cells (hBMSCs). We prepared PLA scaffolds and coated with polydopamine (PDA). The chemical composition and surface properties of PLA/PDA/XD were characterized by XPS. PLA/PDA/XD controlled hBMSCs’ responses in several ways. Firstly, adhesion and proliferation of hBMSCs cultured on PLA/PDA/XD were significantly enhanced relative to those on PLA. In addition, the focal adhesion kinase (FAK) expression of cells was increased and promoted cell attachment depended on the XD content. In osteogenesis assay, the osteogenesis markers of hBMSCs cultured on PLA/PDA/XD were significantly higher than seen in those cultured on a pure PLA/PDA scaffolds. Moreover, hBMSCs cultured on PLA/PDA/XD showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hBMSCs. PMID:28793441
Chung, Eun-Jae; Jun, Dae-Ryong; Kim, Dong-Wook; Han, Mi-Jung; Kwon, Tack-Kyun; Choi, Sung-Wook; Kwon, Seong Keun
2017-01-01
The use of injectable bulking agents is a feasible alternative procedure for conventional surgical therapy. In this study, poly(dimethylsiloxane) (PDMS) microspheres coated with polydopamine (PDA) were developed as a potential injection agent to prevent migration in vocal fold. Uniform PDMS microspheres are fabricated using a simple fluidic device and then coated with PDA. Cell attachment test reveals that the PDA-coated PDMS (PDA-PDMS) substrate favors cell adhesion and attachment. The injected PDA-PDMS microspheres persist without migration on reconstructed axial CT images, whereas, pristine PDMS locally migrates over a period of 12 weeks. The gross appearance of the implants retrieved at 4, 8, 12 and 34 weeks indicates that the PDA-PDMS group maintained their original position without significant migration until 34 weeks after injection. By contrast, there is diffuse local migration of the pristine PDMS group from 4 weeks after injection. The PDA-coated PDMS microspheres can potentially be used as easily injectable, non-absorbable filler without migration.
Kim, Dong-Wook; Han, Mi-Jung; Kwon, Tack-Kyun; Choi, Sung-Wook
2017-01-01
The use of injectable bulking agents is a feasible alternative procedure for conventional surgical therapy. In this study, poly(dimethylsiloxane) (PDMS) microspheres coated with polydopamine (PDA) were developed as a potential injection agent to prevent migration in vocal fold. Uniform PDMS microspheres are fabricated using a simple fluidic device and then coated with PDA. Cell attachment test reveals that the PDA-coated PDMS (PDA-PDMS) substrate favors cell adhesion and attachment. The injected PDA-PDMS microspheres persist without migration on reconstructed axial CT images, whereas, pristine PDMS locally migrates over a period of 12 weeks. The gross appearance of the implants retrieved at 4, 8, 12 and 34 weeks indicates that the PDA-PDMS group maintained their original position without significant migration until 34 weeks after injection. By contrast, there is diffuse local migration of the pristine PDMS group from 4 weeks after injection. The PDA-coated PDMS microspheres can potentially be used as easily injectable, non-absorbable filler without migration. PMID:29095854
In vitro genotoxicity and cytotoxicity of polydopamine-coated magnetic nanostructures.
Woźniak, Anna; Walawender, Magdalena; Tempka, Dominika; Coy, Emerson; Załęski, Karol; Grześkowiak, Bartosz F; Mrówczyński, Radosław
2017-10-01
Synthesis of magnetic nanoparticles and magnetic nanoclusters was performed by the co-precipitation method or solvothermal synthesis, respectively, followed by oxidative polymerization of dopamine, resulting in a polydopamine (PDA) shell. The nanomaterials obtained were described using TEM, FTIR and magnetic measurements. For the first time, cyto- and genotoxicity studies of polydopamine-coated nanostructures were performed on cancer and normal cell lines, providing in-depth insight into the toxicity of such materials. The tests conducted, e.g. ROS, apoptosis and DNA double-break of the nanomaterials obtained revealed the low toxicity of these structures. Thus, these results prove the biocompatibility and low genotoxicity of these materials and provide new data on the toxicity of PDA-coated materials, which is of great importance for their biomedical application. Copyright © 2017 Elsevier Ltd. All rights reserved.
Paleo Data Assimilation of Pseudo-Tree-Ring-Width Chronologies in a Climate Model
NASA Astrophysics Data System (ADS)
Fallah Hassanabadi, B.; Acevedo, W.; Reich, S.; Cubasch, U.
2016-12-01
Using the Time-Averaged Ensemble Kalman Filter (EnKF) and a forward model, we assimilate the pseudo Tree-Ring-Width (TRW) chronologies into an Atmospheric Global Circulation model. This study investigates several aspects of Paleo-Data Assimilation (PDA) within a perfect-model set-up: (i) we test the performance of several forward operators in the framework of a PDA-based climate reconstruction, (ii) compare the PDA-based simulations' skill against the free ensemble runs and (iii) inverstigate the skill of the "online" (with cycling) DA and the "off-line" (no-cycling) DA. In our experiments, the "online" (with cycling) PDA approach did not outperform the "off-line" (no-cycling) one, despite its considerable additional implementation complexity. On the other hand, it was observed that the error reduction achieved by assimilating a particular pseudo-TRW chronology is modulated by the strength of the yearly internal variability of the model at the chronology site. This result might help the dendrochronology community to optimize their sampling efforts.
The necrosome promotes pancreatic oncogenesis via CXCL1 and Mincle-induced immune suppression.
Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Barilla, Rocky; Daley, Donnele; Greco, Stephanie H; Torres-Hernandez, Alejandro; Pergamo, Matthew; Ochi, Atsuo; Zambirinis, Constantinos P; Pansari, Mridul; Rendon, Mauricio; Tippens, Daniel; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Engle, Dannielle; Miller, George
2016-04-14
Neoplastic pancreatic epithelial cells are believed to die through caspase 8-dependent apoptotic cell death, and chemotherapy is thought to promote tumour apoptosis. Conversely, cancer cells often disrupt apoptosis to survive. Another type of programmed cell death is necroptosis (programmed necrosis), but its role in pancreatic ductal adenocarcinoma (PDA) is unclear. There are many potential inducers of necroptosis in PDA, including ligation of tumour necrosis factor receptor 1 (TNFR1), CD95, TNF-related apoptosis-inducing ligand (TRAIL) receptors, Toll-like receptors, reactive oxygen species, and chemotherapeutic drugs. Here we report that the principal components of the necrosome, receptor-interacting protein (RIP)1 and RIP3, are highly expressed in PDA and are further upregulated by the chemotherapy drug gemcitabine. Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype. By contrast, in vivo deletion of RIP3 or inhibition of RIP1 protected against oncogenic progression in mice and was associated with the development of a highly immunogenic myeloid and T cell infiltrate. The immune-suppressive tumour microenvironment associated with intact RIP1/RIP3 signalling depended in part on necroptosis-induced expression of the chemokine attractant CXCL1, and CXCL1 blockade protected against PDA. Moreover, cytoplasmic SAP130 (a subunit of the histone deacetylase complex) was expressed in PDA in a RIP1/RIP3-dependent manner, and Mincle--its cognate receptor--was upregulated in tumour-infiltrating myeloid cells. Ligation of Mincle by SAP130 promoted oncogenesis, whereas deletion of Mincle protected against oncogenesis and phenocopied the immunogenic reprogramming of the tumour microenvironment that was induced by RIP3 deletion. Cellular depletion suggested that whereas inhibitory macrophages promote tumorigenesis in PDA, they lose their immune-suppressive effects when RIP3 or Mincle is deleted. Accordingly, T cells, which are not protective against PDA progression in mice with intact RIP3 or Mincle signalling, are reprogrammed into indispensable mediators of anti-tumour immunity in the absence of RIP3 or Mincle. Our work describes parallel networks of necroptosis-induced CXCL1 and Mincle signalling that promote macrophage-induced adaptive immune suppression and thereby enable PDA progression.
Imai, Daisuke; Yoshizumi, Tomoharu; Okano, Shinji; Uchiyama, Hideaki; Ikegami, Toru; Harimoto, Norifumi; Itoh, Shinji; Soejima, Yuji; Aishima, Shinichi; Oda, Yoshinao; Maehara, Yoshihiko
2017-07-01
Pancreatic ductal adenocarcinoma (PDA) is associated with an immunosuppressive tumor-microenvironment (TME) that supports the growth of tumors and mediates tumors enabling evasion of the immune system. Expression of programmed cell death ligand 1 (PD-L1) and loss of human leukocyte antigen (HLA) class I on tumor cells are methods by which tumors escape immunosurveillance. We examined immune cell infiltration, the expression of PD-L1 and HLA class I by PDA cells, and the correlation between these immunological factors and clinical prognosis. PDA samples from 36 patients were analyzed for HLA class I, HLA-DR, PD-L1, PD-1, CD4, CD8, CD56, CD68, and FoxP3 expression by immunohistochemistry. The correlations between the expression of HLA class I, HLA-DR, PD-L1 or PD-1 and the pattern of tumor infiltrating immune cells or the patients' prognosis were assessed. PD-L1 expression correlated with tumor infiltration by CD68 + and FoxP3 + cells. Low HLA class I expression was an only risk factor for poor survival. PD-L1 negative and HLA class I high-expressing PDA was significantly associated with higher numbers of infiltrating CD8 + T cells in the TME, and a better prognosis. Evaluation of both PD-L1 and HLA class I expression by PDA may be a good predictor of prognosis for patients. HLA class I expression by tumor cells should be evaluated when selecting PDA patients who may be eligible for treatment with PD-1/PD-L1 immune checkpoint blockade therapies. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
The Necrosome Promotes Pancreas Oncogenesis via CXCL1 and Mincle Induced Immune Suppression
Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Barilla, Rocky; Daley, Donnele; Greco, Stephanie H.; Torres-Hernandez, Alejandro; Pergamo, Matthew; Ochi, Atsuo; Zambirinis, Constantinos P.; Pansari, Mridul; Rendon, Mauricio; Tippens, Daniel; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Engle, Dannielle; Miller, George
2016-01-01
Neoplastic pancreatic epithelial cells are widely believed to die via Caspase 8-dependant apoptotic cell death and chemotherapy is thought to further promote tumor apoptosis1. Conversely, disruption of apoptosis is a basic modality cancer cells exploit for survival2,3. However, the role of necroptosis, or programmed necrosis, in pancreatic ductal adenocarcinoma (PDA) is uncertain. There are a multitude of potential inducers of necroptosis in PDA including ligation of TNFR1, CD95, TRAIL receptors, Toll-like receptors, ROS, and Chemotherapeutics4,5. Here we report that the principal components of the necrosome, RIP1 and RIP3, are highly expressed in PDA and are further upregulated by chemotherapy. Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype. By contrast, in vivo RIP3 deletion or RIP1 inhibition was protective against oncogenic progression and was associated with the development of a highly immunogenic myeloid and T cell infiltrate. The immune-suppressive tumor microenvironment (TME) associated with intact RIP1/RIP3 signaling was in-part contingent on necroptosis-induced CXCL1 expression whereas CXCL1 blockade was protective against PDA. Moreover, we found that cytoplasmic SAP130 was expressed in PDA in a RIP1/RIP3-dependent manner, and Mincle – its cognate receptor – was upregulated in tumor-infiltrating myeloid cells. Mincle ligation by SAP130 promoted oncogenesis whereas Mincle deletion was protective and phenocopied the immunogenic reprogramming of the TME characteristic of RIP3 deletion. Cellular depletion experiments suggested that whereas inhibitory macrophages promote tumorigenesis in PDA, they lose their immune-suppressive effects in the context of RIP3 or Mincle deletion. As such, T cells which are dispensable to PDA progression in hosts with intact RIP3 or Mincle signaling become reprogrammed into indispensable mediators of anti-tumor immunity in absence of RIP3 or Mincle. Our work describes parallel networks of necroptosis-induced CXCL1 and Mincle signaling which critically promote macrophage-induced adaptive immune suppression enabling PDA progression. PMID:27049944
Genotyping and expression analysis of IDO2 in human pancreatic cancer: a novel, active target.
Witkiewicz, Agnieszka K; Costantino, Christina L; Metz, Richard; Muller, Alexander J; Prendergast, George C; Yeo, Charles J; Brody, Jonathan R
2009-05-01
The recently discovered indoleamine 2,3-dioxygenase-2 (IDO2) gene has 2 functional polymorphisms that abolish its enzymatic activity. We hypothesize that expression of the IDO2 enzyme in primary pancreatic ductal adenocarcinomas (PDA) can help cancer cells evade immune detection. Because the IDO2 enzyme might be the preferential target of d-1-methyl-tryptophan, a clinical lead inhibitor of IDO currently being evaluated in phase I trials, we sequenced IDO2 in 36 pancreatic specimens and evaluated its expression. We found that 58% (21 of 36) of cases were heterozygous for the R248W polymorphism; 28% (10 of 36) were homozygous wild-type; and only 14% (5 of 36) were homozygous for the functionally inactive polymorphism. As for the Y359STOP polymorphism, we found that 27% (10 of 36) of cases were heterozygous, 62% (22 of 36) were homozygous wild-type, and only 11% (4 of 36) were homozygous for this functionally inactive allele. Ruling out the possibility of compound polymorphic variants, we estimated 75% of our resected patient cohort had an active IDO2 enzyme, with a conservative estimate that 58% of the patients had at least 1 functional allele. IDO2 was expressed in PDA tissue from each genetically polymorphic subgroup. We also detected IDO2 protein expression in the genetically distinct pancreatic cancer cell lines after exposure with interferon-gamma. This is the first study to report IDO2 expression in PDA and related cancers indicating that IDO2 genetic polymorphisms do not negate interferon-gamma-inducible protein expression. Taken together, our data strongly suggest that the clinical lead compound d-1-methyl-tryptophan might be useful in treatment of PDA.
Targeting reactive oxygen species in development and progression of pancreatic cancer
Durand, Nisha; Storz, Peter
2017-01-01
Introduction Pancreatic ductal adenocarcinoma (PDA) is characterized by expression of oncogenic KRas which drives all aspects of tumorigenesis. Oncogenic KRas induces the formation of reactive oxygen species (ROS) which have been implicated in initiation and progression of PDA. To facilitate tumor promoting levels and to avoid oncogene-induced senescence or cytotoxicity, ROS homeostasis in PDA cells is balanced by additional up-regulation of antioxidant systems. Areas Covered We examine the sources of ROS in PDA, the mechanisms by which ROS homeostasis is maintained, and the biological consequences of ROS in PDA. Additionally, we discuss the potential mechanisms for targeting ROS homoeostasis as a point of therapeutic intervention. An extensive review of the relevant literature as it relates to the topic was conducted using PubMed. Expert Commentary Even though oncogenic mutations in the KRAS gene have been detected in over 95% of human pancreatic adenocarcinoma, targeting its gene product, KRas, has been difficult. The dependency of PDA cells on balancing ROS homeostasis could be an angle for new prevention or treatment strategies. These include use of antioxidants to prevent formation or progression of precancerous lesions, or methods to increase ROS in tumor cells to toxic levels. PMID:27841037
Piao, Ji-Gang; Gao, Feng; Yang, Lihua
2016-01-13
How to destroy drug-resistant tumor cells remains an ongoing challenge for cancer treatment. We herein report on a therapeutic nanoparticle, aHLP-PDA, which has an acid-activated hemolytic polymer (aHLP) grafted onto photothermal polydopamine (PDA) nanosphere via boronate ester bond, in efforts to ablate drug-resistant tumors. Upon exposure to oxidative stress and/or near-infrared laser irradiation, aHLP-PDA nanoparticle responsively releases aHLP, likely via responsive cleavage of boronate ester bond, and thus responsively exhibits acid-facilitated mammalian-membrane-disruptive activity. In vitro cell studies with drug-resistant and/or thermo-tolerant cancer cells show that the aHLP-PDA nanoparticle demonstrates preferential cytotoxicity at acidic pH over physiological pH. When administered intravenously, the aHLP-PDA nanoparticle exhibits significantly prolonged blood circulation lifetime and enhanced tumor uptake compared to bare PDA nanosphere, likely owing to aHLP's stealth effects conferred by its zwitterionic nature at blood pH. As a result, the aHLP-PDA nanoparticle effectively ablates drug-resistant tumors, leading to 100% mouse survival even on the 32nd day after suspension of photothermal treatment, as demonstrated with the mouse model. This work suggests that a combination of nanotechnology with lessons learned in bacterial antibiotic resistance may offer a feasible and effective strategy for treating drug-resistant cancers often found in relapsing patients.
Lublin, Fred D; Bowen, James D; Huddlestone, John; Kremenchutzky, Marcelo; Carpenter, Adam; Corboy, John R; Freedman, Mark S; Krupp, Lauren; Paulo, Corri; Hariri, Robert J; Fischkoff, Steven A
2014-11-01
Infusion of PDA-001, a preparation of mesenchymal-like cells derived from full-term human placenta, is a new approach in the treatment of patients with multiple sclerosis. This safety study aimed to rule out the possibility of paradoxical exacerbation of disease activity by PDA-001 in patients with multiple sclerosis. This was a phase 1b, multicenter, randomized, double-blind, placebo-controlled, 2-dose ranging study including patients with relapsing-remitting multiple sclerosis or secondary progressive multiple sclerosis. The study was conducted at 6 sites in the United States and 2 sites in Canada. Patients were randomized 3:1 to receive 2 low-dose infusions of PDA-001 (150×10(6) cells) or placebo, given 1 week apart. After completing this cohort, subsequent patients received high-dose PDA-001 (600×10(6) cells) or placebo. Monthly brain magnetic resonance imaging scans were performed. The primary end point was ruling out the possibility of paradoxical worsening of MS disease activity. This was monitored using Cutter׳s rule (≥5 new gadolinium lesions on 2 consecutive scans) by brain magnetic resonance imaging on a monthly basis for six months and also the frequency of multiple sclerosis relapse. Ten patients with relapsing-remitting multiple sclerosis and 6 with secondary progressive multiple sclerosis were randomly assigned to treatment: 6 to low-dose PDA-001, 6 to high-dose PDA-001, and 4 to placebo. No patient met Cutter׳s rule. One patient receiving high-dose PDA-001 had an increase in T2 and gadolinium lesions and in Expanded Disability Status Scale score during a multiple sclerosis flare 5 months after receiving PDA-001. No other patient had an increase in Expanded Disability Status Scale score>0.5, and most had stable or decreasing Expanded Disability Status Scale scores. With high-dose PDA-001, 1 patient experienced a grade 1 anaphylactoid reaction and 1 had grade 2 superficial thrombophlebitis. Other adverse events were mild to moderate and included headache, fatigue, infusion site reactions, and urinary tract infection. PDA-001 infusions were safe and well tolerated in relapsing-remitting multiple sclerosis and secondary progressive multiple sclerosis patients. No paradoxical worsening of lesion counts was noted with either dose. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
Targeted depletion of a MDSC subset unmasks pancreatic ductal adenocarcinoma to adaptive immunity
Stromnes, Ingunn M.; Brockenbrough, Scott; Izeradjene, Kamel; Carlson, Markus A.; Cuevas, Carlos; Simmons, Randi M.; Greenberg, Philip D.; Hingorani, Sunil R.
2015-01-01
Objective Pancreatic ductal adenocarcinoma (PDA) is characterized by a robust desmoplasia, including the notable accumulation of immunosuppressive cells that shield neoplastic cells from immune detection. Immune evasion may be further enhanced if the malignant cells fail to express high levels of antigens that are sufficiently immunogenic to engender an effector T cell response. In this report, we investigate the predominant subsets of immunosuppressive cancer-conditioned myeloid cells that chronicle and shape pancreas cancer progression. We show that selective depletion of one subset of myeloid-derived suppressor cells (MDSC) in an autochthonous, genetically engineered mouse model (GEMM) of PDA unmasks the ability of the adaptive immune response to engage and target tumor epithelial cells. Methods A combination of in vivo and in vitro studies were performed employing a GEMM that faithfully recapitulates the cardinal features of human PDA. The predominant cancer-conditioned myeloid cell subpopulation was specifically targeted in vivo and the biological outcomes determined. Results PDA orchestrates the induction of distinct subsets of cancer-associated myeloid cells through the production of factors known to influence myelopoeisis. These immature myeloid cells inhibit the proliferation and induce apoptosis of activated T cells. Targeted depletion of granulocytic MDSC (Gr-MDSC) in autochthonous PDA increases the intratumoral accumulation of activated CD8 T cells and apoptosis of tumor epithelial cells, and also remodels the tumor stroma. Conclusions Neoplastic ductal cells of the pancreas induce distinct myeloid cell subsets that promote tumor cell survival and accumulation. Targeted depletion of a single myeloid subset, the Gr-MDSC, can unmask an endogenous T cell response, revealing an unexpected latent immunity and invoking targeting of Gr-MDSC as a potential strategy to exploit for treating this highly lethal disease. PMID:24555999
Soares, Kevin C.; Rucki, Agnieszka A.; Wu, Annie A.; Olino, Kelly; Xiao, Qian; Chai, Yi; Wamwea, Anthony; Bigelow, Elaine; Lutz, Eric; Liu, Linda; Yao, Sheng; Anders, Robert A.; Laheru, Daniel; Wolfgang, Christopher L.; Edil, Barish H.; Schulick, Richard D.; Jaffee, Elizabeth M.; Zheng, Lei
2014-01-01
Pancreatic ductal adenocarcinoma (PDA) has a poor prognosis due to late detection and resistance to conventional therapies. Published studies show that the PDA tumor microenvironment (TME) is predominantly infiltrated with immune suppressive cells and signals that if altered, would allow effective immunotherapy. However, single-agent checkpoint inhibitors including agents that alter immune suppressive signals in other human cancers such as cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed death 1 (PD-1) and its ligand PD-L1, have failed to demonstrate objective responses when given as single agents to PDA patients. We recently reported that inhibition of the CTLA-4 pathway when given together with a T cell inducing vaccine gives objective responses in metastatic PDA patients. In this study, we evaluated blockade of the PD-1/PD-L1 pathway. We found that PD-L1 is weakly expressed at a low frequency in untreated human and murine PDAs but treatment with a GM-CSF secreting PDA vaccine (GVAX) significantly upregulates PD-L1 membranous expression after treatment of tumor bearing mice. In addition, combination therapy with vaccine and PD-1 antibody blockade improved murine survival compared to PD-1 antibody monotherapy or GVAX therapy alone. Furthermore, PD-1 blockade increased effector CD8+ T lymphocytes and tumor-specific interferon-γ production of CD8+ T cells in the TME. Immunosuppressive pathways, including regulatory T cells (Tregs) and CTLA-4 expression on T cells were overcome by the addition of vaccine and low dose cyclophosphamide to PD-1 blockade. Collectively, our study supports combining PD-1 or PD-L1 antibody therapy with a T cell inducing agent for PDA treatment. PMID:25415283
Feig, Christine; Jones, James O; Kraman, Matthew; Wells, Richard J B; Deonarine, Andrew; Chan, Derek S; Connell, Claire M; Roberts, Edward W; Zhao, Qi; Caballero, Otavia L; Teichmann, Sarah A; Janowitz, Tobias; Jodrell, Duncan I; Tuveson, David A; Fearon, Douglas T
2013-12-10
An autochthonous model of pancreatic ductal adenocarcinoma (PDA) permitted the analysis of why immunotherapy is ineffective in this human disease. Despite finding that PDA-bearing mice had cancer cell-specific CD8(+) T cells, the mice, like human patients with PDA, did not respond to two immunological checkpoint antagonists that promote the function of T cells: anti-cytotoxic T-lymphocyte-associated protein 4 (α-CTLA-4) and α-programmed cell death 1 ligand 1 (α-PD-L1). Immune control of PDA growth was achieved, however, by depleting carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). The depletion of the FAP(+) stromal cell also uncovered the antitumor effects of α-CTLA-4 and α-PD-L1, indicating that its immune suppressive activity accounts for the failure of these T-cell checkpoint antagonists. Three findings suggested that chemokine (C-X-C motif) ligand 12 (CXCL12) explained the overriding immunosuppression by the FAP(+) cell: T cells were absent from regions of the tumor containing cancer cells, cancer cells were coated with the chemokine, CXCL12, and the FAP(+) CAF was the principal source of CXCL12 in the tumor. Administering AMD3100, a CXCL12 receptor chemokine (C-X-C motif) receptor 4 inhibitor, induced rapid T-cell accumulation among cancer cells and acted synergistically with α-PD-L1 to greatly diminish cancer cells, which were identified by their loss of heterozygosity of Trp53 gene. The residual tumor was composed only of premalignant epithelial cells and inflammatory cells. Thus, a single protein, CXCL12, from a single stromal cell type, the FAP(+) CAF, may direct tumor immune evasion in a model of human PDA.
Manabe, Yuki; Hirata, Takashi; Sugawara, Tatsuya
2014-01-01
In this study, the anti-degranulation effects of fifteen carotenoids were evaluated using RBL-2H3 rat basophilic leukemia cell line as a mast cell model. Nine carotenoids, fucoxanthin, zeaxanthin, β-carotene, astaxanthin, 3-hydroxyechinenone, fucoxanthinol, lycopene, β-cryptoxanthin, and siphonaxanthin significantly suppressed antigen-induced mast cell degranulation. Under the same conditions, the cellular carotenoid contents were quantified using high performance liquid chromatography-photodiode array (HPLC-PDA). There was no correlation between the cellular carotenoid contents and their anti-degranulation activities. These results indicate that the differences in the anti-degranulation activities of carotenoids were not related to their uptake by the cells.
Liu, Liang; Ma, Siyuan; Pei, Yunheng; Xiong, Xiao; Sivakumar, Preeth; Singler, Timothy J
2016-08-24
We report a method to achieve highly uniform inkjet-printed silver nitrate (AgNO3) and a reactive silver precursor patterns on rigid and flexible substrates functionalized with polydopamine (PDA) coatings. The printed AgNO3 patterns on PDA-coated substrates (glass and polyethylene terephthalate (PET)) exhibit a narrow thickness distribution ranging between 0.9 and 1 μm in the line transverse direction and uniform deposition profiles in the line axial direction. The deposited reactive silver precursor patterns on PDA-functionalized substrates also show "dome-shaped" morphology without "edge-thickened" structure due to "coffee-stain" effect. We posit that the highly uniform functional ink deposits formed on PDA-coated substrates are attributable to the strong binding interaction between the abundant catecholamine moieties at the PDA surface and the metallic silver cations (Ag(+) or Ag(NH3)(2+)) in the solutal inks. During printing of the ink rivulet and solvent evaporation, the substrate-liquid ink (S-L) interface is enriched with the silver-based cations and a solidification at the S/L interface is induced. The preferential solidification initiated at the S-L interface is further verified by the in situ visualization of the dynamic solidification process during solvent evaporation, and results suggest an enhanced crystal nucleation and growth localized at the S-L interface on PDA functionalized substrates. This interfacial interaction mediates solute transport in the liquid phase, resulting in the controlled enrichment of solute at the S-L interface and mitigated solute precipitation in both the contact line region and the liquid ink-vapor (L-V) interface due to evaporation. This mediated transport contributes to the final uniform solid deposition for both types of ink systems. This technique provides a complementary strategy for achieving highly uniform inkjet-printed crystalline structures, and can serve as an innovative foundation for high-precision additive delivery of functional materials.
Pancreatic stellate cells (PSCs) differentiate into cancer-associated fibroblasts (CAFs) that produce desmoplastic stroma, thereby modulating disease progression and therapeutic response in pancreatic ductal adenocarcinoma (PDA). However, it is unknown whether CAFs uniformly carry out these tasks or if subtypes of CAFs with distinct phenotypes in PDA exist. We identified a CAF subpopulation with elevated expression of α-smooth muscle actin (αSMA) located immediately adjacent to neoplastic cells in mouse and human PDA tissue.
ERIC Educational Resources Information Center
Dodds, Richard; Mason, Christine Y.
2005-01-01
Although cell phones keep kids in touch with families and personal digital assistants (PDA's) help organize assignments and give Internet access, when they are added to the school climate, educators must reassess policies so technology does not interfere with instruction time. This article discusses the several effects of cell phones to K-6…
Architectures for Device Aware Network
2005-03-01
68 b. PDA in DAN Mode ............................................................. 69 c. Cell Phone in DAN Mode...68 Figure 15. PDA in DAN Mode - Reduced Resolution Image ..................................... 69 Figure 16. Cell Phone in DAN Mode -No Image...computer, notebook computer, cell phone and a host of networked embedded systems) may have extremely differing capabilities and resources to retrieve and
Martínez-Bosch, Neus; Fernández-Barrena, Maite G.; Moreno, Mireia; Ortiz-Zapater, Elena; André, Sabine; Gabius, Hans-Joachim; Hwang, Rosa F.; Poirier, Françoise; Munné-Collado, Jessica; Iglesias, Mar; Navas, Carolina; Guerra, Carmen; Fernández-Zapico, Martin E.; Navarro, Pilar
2015-01-01
Pancreatic ductal adenocarcinoma (PDA) is the most aggressive tumor, showing incidence and mortality values almost identical. Despite remarkable advances in PDA molecular characterization, this disease is still refractory to current treatments. Desmoplastic stroma, a constant hallmark of PDA, has recently emerged as the major responsible for PDA therapeutic resistance, therefore representing a promising target. Galectin-1 (Gal1), a glycan-binding protein, is highly expressed in PDA stroma but its role remains unknown. Here, we aim to understand in vivo Gal1 functions and the molecular pathways responsible for its oncogenic properties. Genetic ablation of Gal1 in Ela-myc mice dampens tumor progression through inhibition of proliferation, angiogenesis, desmoplasia and stimulation of tumor-associated immune response, resulting in a 20% increase on the animal life span. In vitro and in vivo studies unveil that these effects are mediated by modulation of the tumor microenvironment in a non-cell autonomous manner. Importantly, acinar-to-ductal metaplasia, a crucial step for PDA initiation, is also regulated by Gal1. Finally, high-throughput gene expression studies and molecular analysis aimed at identifying the underlying mechanism revealed that Gal1 promotes Hedgehog pathway both in PDA cells and stromal fibroblasts. In summary, our studies define a novel role of Gal1 in PDA tumor epithelium-stroma crosstalk and suggest this lectin as potential molecular target for therapy of neoplasms overexpressing Gal1. PMID:24812270
NASA Astrophysics Data System (ADS)
Jiang, Hongmei; Yang, Lu; Deng, Wenfang; Tan, Yueming; Xie, Qingji
2017-09-01
Herein, a macroporous graphitic carbon foam (MGCF) electrode decorated with polydopamine (PDA) is used as a high-performance anode for microbial fuel cell (MFC) applications. The MGCF is facilely prepared by pyrolysis of a powder mixture comprising maltose, nickel nitrate, and ammonia chloride, without using solid porous template. The MGCF is coated with PDA by self-polymerization of dopamine in a basic solution. The MGCF can provide a large surface area for bacterial attachment, and PDA coated on the MGCF electrode can further promote bacterial adhesion resulting from the improved hydrophility, so the MGCF-PDA electrode as an anode in a MFC can show ultrahigh bacterial loading capacity. Moreover, the electrochemical oxidation of flavins at the MGCF-PDA electrode is greatly accelerated, so the extracellular electron transfer mediated by flavins is improved. As a result, the MFC equipped with a MGCF-PDA anode can show a maximum power density of 1735 mW cm-2, which is 6.7 times that of a MFC equipped with a commercial carbon felt anode, indicating a promising anode for MFC applications.
NASA Astrophysics Data System (ADS)
Du, Qing; An, Jingkun; Li, Junhui; Zhou, Lean; Li, Nan; Wang, Xin
2017-03-01
The bacterial anode material is important to the performance of microbial fuel cells (MFCs) because its characteristics affect the biofilm formation and extracellular electron transfer. Here we find that a superhydrophilic semiconductor, polydopamine (PDA), is an effective modification material for the anode to accelerate startup and improve power density. When the activated carbon anode is added with 50% (wt.) PDA, the startup time is 14% shorter than the control (from 88 h to 76 h), with a 31% increase in maximum power density from 613 ± 9 to 803 ± 6 mW m-2, and the Columbic efficiency increases from 19% to 48%. These can be primarily attributed to the abundant functional groups (such as amino group, and catechol functions) introduced by PDA that improve hydrophilicity and extracellular electron transfer. PDA also increases proportions of Proteobacteria and Firmicutes families, indicating that PDA has a selective effect on anode microbial community. Our findings provide a new approach to accelerate anode biofilm formation and enhance MFC power output by modification of biocompatible PDA.
Choi, Chun Kit K; Li, Jinming; Wei, Kongchang; Xu, Yang J; Ho, Lok Wai C; Zhu, Meiling; To, Kenneth K W; Choi, Chung Hang J; Bian, Liming
2015-06-17
The capability of monitoring the differentiation process in living stem cells is crucial to the understanding of stem cell biology and the practical application of stem-cell-based therapies, yet conventional methods for the analysis of biomarkers related to differentiation require a large number of cells as well as cell lysis. Such requirements lead to the unavoidable loss of cell sources and preclude real-time monitoring of cellular events. In this work, we report the detection of microRNAs (miRNAs) in living human mesenchymal stem cells (hMSCs) by using polydopamine-coated gold nanoparticles (Au@PDA NPs). The PDA shell facilitates the immobilization of fluorescently labeled hairpin DNA strands (hpDNAs) that can recognize specific miRNA targets. The gold core and PDA shell quench the fluorescence of the immobilized hpDNAs, and subsequent binding of the hpDNAs to the target miRNAs leads to their dissociation from Au@PDA NPs and the recovery of fluorescence signals. Remarkably, these Au@PDA-hpDNA nanoprobes can naturally enter stem cells, which are known for their poor transfection efficiency, without the aid of transfection agents. Upon cellular uptake of these nanoprobes, we observe intense and time-dependent fluorescence responses from two important osteogenic marker miRNAs, namely, miR-29b and miR-31, only in hMSCs undergoing osteogenic differentiation and living primary osteoblasts but not in undifferentiated hMSCs and 3T3 fibroblasts. Strikingly, our nanoprobes can afford long-term tracking of miRNAs (5 days) in the differentiating hMSCs without the need of continuously replenishing cell culture medium with fresh nanoprobes. Our results demonstrate the capability of our Au@PDA-hpDNA nanoprobes for monitoring the differentiation status of hMSCs (i.e., differentiating versus undifferentiated) via the detection of specific miRNAs in living stem cells. Our nanoprobes show great promise in the investigation of the long-term dynamics of stem cell differentiation, identification and isolation of specific cell types, and high-throughput drug screening.
Wang, Yanying; Liu, Yaqin; Ding, Fang; Zhu, Xiaoyan; Yang, Li; Zou, Ping; Rao, Hanbing; Zhao, Qingbiao; Wang, Xianxiang
2018-06-07
In this study, we developed a simple colorimetric approach to detect glutathione (GSH). The proposed approach is based on the ability of CuS-PDA-Au composite material to catalytically oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to ox-TMB to induce a blue color with an absorption peak centered at 652 nm. However, the introduction of GSH can result in a decrease in oxidized TMB; similarly, it can combine with Au nanoparticles (Au NPs) on the surface of CuS-PDA-Au composite material. Both approaches can result in a fading blue color and a reduction of the absorbance at 652 nm. Based on this above, we proposed a technique to detect GSH quantitatively and qualitatively through UV-Vis spectroscopy and naked eye, respectively. This approach demonstrates a low detection limit of 0.42 μM with a broad detection range of 5 × 10 -7 -1 × 10 -4 M with the assistance of UV-Vis spectroscopy. More importantly, this approach is convenient and rapid. This method was successfully applied to GSH detection in human serum and cell lines. Graphical abstract A colorimetric approach has been developed by exploiting the peroxidase-like activity of CuS-polydopamine-Au composite for sensitive glutathione detection.
Targeting galectin-1 inhibits pancreatic cancer progression by modulating tumor-stroma crosstalk.
Orozco, Carlos A; Martinez-Bosch, Neus; Guerrero, Pedro E; Vinaixa, Judith; Dalotto-Moreno, Tomás; Iglesias, Mar; Moreno, Mireia; Djurec, Magdolna; Poirier, Françoise; Gabius, Hans-Joachim; Fernandez-Zapico, Martin E; Hwang, Rosa F; Guerra, Carmen; Rabinovich, Gabriel A; Navarro, Pilar
2018-04-17
Pancreatic ductal adenocarcinoma (PDA) remains one of the most lethal tumor types, with extremely low survival rates due to late diagnosis and resistance to standard therapies. A more comprehensive understanding of the complexity of PDA pathobiology, and especially of the role of the tumor microenvironment in disease progression, should pave the way for therapies to improve patient response rates. In this study, we identify galectin-1 (Gal1), a glycan-binding protein that is highly overexpressed in PDA stroma, as a major driver of pancreatic cancer progression. Genetic deletion of Gal1 in a Kras -driven mouse model of PDA ( Ela-Kras G12V p53 -/- ) results in a significant increase in survival through mechanisms involving decreased stroma activation, attenuated vascularization, and enhanced T cell infiltration leading to diminished metastasis rates. In a human setting, human pancreatic stellate cells (HPSCs) promote cancer proliferation, migration, and invasion via Gal1-driven pathways. Moreover, in vivo orthotopic coinjection of pancreatic tumor cells with Gal1-depleted HPSCs leads to impaired tumor formation and metastasis in mice. Gene-expression analyses of pancreatic tumor cells exposed to Gal1 reveal modulation of multiple regulatory pathways involved in tumor progression. Thus, Gal1 hierarchically regulates different events implicated in PDA biology including tumor cell proliferation, invasion, angiogenesis, inflammation, and metastasis, highlighting the broad therapeutic potential of Gal1-specific inhibitors, either alone or in combination with other therapeutic modalities.
Creydt, Virginia Pistone; Sacca, Paula Alejandra; Tesone, Amelia Julieta; Vidal, Luciano; Calvo, Juan Carlos
2010-01-01
Stromal tissue regulates the development and differentiation of breast epithelial cells, with adipocytes being the main stromal cell type. The aim of the present study was to evaluate the effect of adipocyte differentiation on proliferation and migration, as well as to assess the activity of heparanase and metalloproteinase-9 (MMP-9), in normal (NMuMG) and tumoral (LM3) murine breast epithelial cells. NMuMG and LM3 cells were grown on irradiated 3T3-L1 cells (stromal support, SS) at various degrees of differentiation [preadipocytes (preA), poorly differentiated adipocytes (pDA) and mature adipocytes (MA)] and/or were incubated in the presence of conditioned medium (CM) derived from each of these three types of differentiated cells. Cells grown on a plastic support or in fresh medium served as the controls. Cell proliferation was measured with a commercial colorimetric kit, and the motility of the epithelial cells was evaluated by means of a wound-healing assay. Heparanase activity was assessed by quantifying heparin degradation, and the expression of MMP-9 was determined using Western blotting. The results indicate that cell proliferation was increased after 24 and 48 h in the NMuMG and LM3 cells grown on preA, pDA and MA SS. In the NMuMG cells cultured on SS in the presence of all three types of CM, proliferation was enhanced. LM3 cell migration was increased in the presence of all three types of CM and in cells grown on preA SS. Heparanase activity was increased in the NMuMG cells incubated with all three types of CM, and in the LM3 cells incubated with the CM from pDA and MA. Both the NMuMG and LM3 cell lines presented basal expression of MMP-9; however, a significant increase in MMP-9 expression was observed in the LM3 cells incubated with each of the three types of CM. In conclusion, adipocyte differentiation influences normal and tumoral breast epithelial cell proliferation and migration. Heparanase and MMP-9 appear to be involved in this regulation. The experimental model presented in this study is in keeping with the characteristics of the physiological environment of breast epithelial cells, in terms of both the soluble and insoluble factors present and the stromal structure per se.
Paracetamol in Patent Ductus Arteriosus Treatment: Efficacious and Safe?
Bardanzellu, Flaminia; Neroni, Paola; Fanos, Vassilios
2017-01-01
In preterm infants, failure or delay in spontaneous closure of Ductus Arteriosus (DA), resulting in the condition of Patent Ductus Arteriosus (PDA), represents a significant issue. A prolonged situation of PDA can be associated with several short- and long-term complications. Despite years of researches and clinical experience on PDA management, unresolved questions about the treatment and heterogeneity of clinical practices in different centers still remain, in particular regarding timing and modality of intervention. Nowadays, the most reasonable strategy seems to be reserving the treatment only to hemodynamically significant PDA. The first-line therapy is medical, and ibuprofen, related to several side effects especially in terms of nephrotoxicity, is the drug of choice. Administration of oral or intravenous paracetamol (acetaminophen) recently gained attention, appearing effective as traditional nonsteroidal anti-inflammatory drugs (NSAIDs) in PDA closure, with lower toxicity. The results of the studies analyzed in this review mostly support paracetamol efficacy in ductal closure, with inconstant low and transient elevation of liver enzymes as reported side effect. However, more studies are needed to confirm if this therapy shows a real safety profile and to evaluate its long-term outcomes, before considering paracetamol as first-choice drug in PDA treatment. PMID:28828381
NASA Astrophysics Data System (ADS)
Pinithchaisakula, A.; Ounnunkad, K.; Themsirimongkon, S.; Promsawan, N.; Waenkaew, P.; Saipanya, S.
2017-02-01
In this work, the preparation, characterization, and electrocatalytic analysis of the catalysts on various carbon substrates for direct alcohol fuel cells were studied. Selected carbons were modified with/without polydopamine (labelled as PDA-C and C) and further metal electrodeposited incorporated onto the glassy carbon (labelled as 5Pt1Pd/PDA-C and 5Pt1Pd/C). Four various carbon materials were used e.g. graphite (G), carbon nanotube (CNT), graphene (GP) and graphene oxide (GO) and the carbons were modified with PDA denoted as PDA-G, PDA-CNT, PDA-GP and PDA-GO, respectively. The transmission electron microscopy (TEM) and scanning electron microscopy (SEM) experimental observation showed narrow size distribution of metal anchored on the PDA-C and C materials. Chemical compositions and oxidation states of the catalysts were determined by X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX). The catalytic performances for small organic electro-oxidation (e.g. methanol and ethanol) were measured by cyclic voltammetry (CV). Among different PDA-C and C catalysts, monometallic Pt showed less activity than the bimetallic catalysts. Among catalysts with PDA, the 5Pt1Pd/PDA-GO catalyst facilitated methanol and ethanol oxidations with high oxidation currents and If/Ib value and stability with low potentials while among catalysts without PDA, the 5Pt1Pd/CNT provides highest activity and stability. It was found that the catalysts with PDA provided high activity and stability than the catalysts without PDA. The improved catalytic performance of the prepared catalysts could be related to the higher active surface area from polymer modification and bimetallic catalyst system in the catalyst composites.
Shen, Hong; Nelson, David M; Oliveira, Regina V; Zhang, Yueping; Mcnaney, Colleen A; Gu, Xiaomei; Chen, Weiqi; Su, Ching; Reily, Michael D; Shipkova, Petia A; Gan, Jinping; Lai, Yurong; Marathe, Punit; Humphreys, W Griffith
2018-02-01
Perturbation of organic anion transporter (OAT) 1- and OAT3-mediated transport can alter the exposure, efficacy, and safety of drugs. Although there have been reports of the endogenous biomarkers for OAT1/3, none of these have all of the characteristics required for a clinical useful biomarker. Cynomolgus monkeys were treated with intravenous probenecid (PROB) at a dose of 40 mg/kg in this study. As expected, PROB increased the area under the plasma concentration-time curve (AUC) of coadministered furosemide, a known substrate of OAT1 and OAT3, by 4.1-fold, consistent with the values reported in humans (3.1- to 3.7-fold). Of the 233 plasma metabolites analyzed using a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics method, 29 metabolites, including pyridoxic acid (PDA) and homovanillic acid (HVA), were significantly increased after either 1 or 3 hours in plasma from the monkeys pretreated with PROB compared with the treated animals. The plasma of animals was then subjected to targeted LC-MS/MS analysis, which confirmed that the PDA and HVA AUCs increased by approximately 2- to 3-fold by PROB pretreatments. PROB also increased the plasma concentrations of hexadecanedioic acid (HDA) and tetradecanedioic acid (TDA), although the increases were not statistically significant. Moreover, transporter profiling assessed using stable cell lines constitutively expressing transporters demonstrated that PDA and HVA are substrates for human OAT1, OAT3, OAT2 (HVA), and OAT4 (PDA), but not OCT2, MATE1, MATE2K, OATP1B1, OATP1B3, and sodium taurocholate cotransporting polypeptide. Collectively, these findings suggest that PDA and HVA might serve as blood-based endogenous probes of cynomolgus monkey OAT1 and OAT3, and investigation of PDA and HVA as circulating endogenous biomarkers of human OAT1 and OAT3 function is warranted. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Munakata, M.; Huang, C.; Menkes, H.
Activated protein kinase C and intracellular Ca/sup + +/ may act synergistically to produce physiological responses. It is possible to activate protein kinase C directly with phorbol esters and to increase intracellular Ca/sup + +/ by depolarizing cell membranes. Guinea pig tracheal rings were incubated at constant temperature in Krebs-Henseleit solution and isometric tension was recorded. Protein kinase C was activated with phorbol 12,13 - diacetate (PDA) and cell membranes were depolarized by lowering temperature, increasing external K/sup +/ concentration, or incubating with ouabain. At 37/sup 0/C, 1 /sup +/M PDA caused a fall in tension (0.67 +/- 0.06 g).more » This decrease in tension was equal to 43% of the near maximal contraction produced by 4 ..mu..M carbachol. At 22/sup 0/C 1 ..mu.. PDA caused an increase in tension (1.00 +/- 0.10 g). This increase in tension was equal to 61% of the contraction produced by 4 ..mu..M carbachol. When K/sup +/ was increased from the physiological concentration of 5.4 mM to 20 mM, 1 ..mu..M PDA caused an increase in tension of 1.11 +/- 0.15 g (56% of the 4 ..mu..M carbachol response). When 10 ..mu..M ouabain was added to the tissue bath, 1 ..mu..M PDA caused an increase in tension of 1.56 +/- 0.61 g (81% of the 4 ..mu..M carbachol response). Contractions produced by PDA at low temperature or high K were blocked by 1 ..mu..M verapamil or by 0.01 ..mu..M nifedipine. The authors conclude that the activation of protein kinase C causes contraction when cell membranes are depolarized and Ca/sup + +/ is allowed to enter the cells through voltage dependent channels.« less
In Situ Live-Cell Nucleus Fluorescence Labeling with Bioinspired Fluorescent Probes.
Ding, Pan; Wang, Houyu; Song, Bin; Ji, Xiaoyuan; Su, Yuanyuan; He, Yao
2017-08-01
Fluorescent imaging techniques for visualization of nuclear structure and function in live cells are fundamentally important for exploring major cellular events. The ideal cellular labeling method is capable of realizing label-free, in situ, real-time, and long-term nucleus labeling in live cells, which can fully obtain the nucleus-relative information and effectively alleviate negative effects of alien probes on cellular metabolism. However, current established fluorescent probes-based strategies (e.g., fluorescent proteins-, organic dyes-, fluorescent organic/inorganic nanoparticles-based imaging techniques) are unable to simultaneously realize label-free, in situ, long-term, and real-time nucleus labeling, resulting in inevitable difficulties in fully visualizing nuclear structure and function in live cells. To this end, we present a type of bioinspired fluorescent probes, which are highly efficacious for in situ and label-free tracking of nucleus in long-term and real-time manners. Typically, the bioinspired polydopamine (PDA) nanoparticles, served as fluorescent probes, can be readily synthesized in situ within live cell nucleus without any further modifications under physiological conditions (37 °C, pH ∼7.4). Compared with other conventional nuclear dyes (e.g., propidium iodide (PI), Hoechst), superior spectroscopic properties (e.g., quantum yield of ∼35.8% and high photostability) and low cytotoxicity of PDA-based probes enable long-term (e.g., 3 h) fluorescence tracking of nucleus. We also demonstrate the generality of this type of bioinspired fluorescent probes in different cell lines and complex biological samples.
The effect of point-of-care personal digital assistant use on resident documentation discrepancies.
Carroll, Aaron E; Tarczy-Hornoch, Peter; O'Reilly, Eamon; Christakis, Dimitri A
2004-03-01
We recently found documentation discrepancies in 60% of resident daily-progress notes with respect to patient weight, medications, or vascular lines. To what extent information systems can decrease such discrepancies is unknown. To determine whether a point-of-care personal digital assistant (PDA)-based patient record and charting system could reduce the number of resident progress-note documentation discrepancies in a neonatal intensive care unit (NICU). We conducted a before-and-after trial in an academic NICU. Our intervention was a PDA-based patient record and charting system used by all NICU resident physicians over the study period. We analyzed all resident daily-progress notes from 40 randomly selected days over 4 months in both the baseline and intervention periods. Using predefined reference standards, we determined the accuracy of recorded information for patient weights, medications, and vascular lines. Logistic and Poisson regression were used in analyses to control for potential confounding factors. A total of 339 progress notes in the baseline period and 432 progress notes in the intervention period were reviewed. When controlling for covariates in the regression, there were significantly fewer documentation discrepancies of patient weights in notes written by using the PDA system (14.4%-4.4% of notes; odds ratio [OR]: 0.29; 95% confidence interval [CI]: 0.15-0.56). When using the PDA system, there were no significant changes in the numbers of notes with documentation discrepancies of medications (27.7%-17.1% of notes; OR: 0.63; 95% CI: 0.35-1.13) or vascular lines (33.6%-36.1% of notes; OR: 1.11; 95% CI: 0.66-1.87). The use of our PDA-based point-of-care patient record and charting system showed a modest benefit in reducing the number of documentation discrepancies in resident daily-progress notes. Further study of PDAs in information systems is warranted before they are widely adopted.
Sun, Gaofeng; Wang, Tao; Li, Xiao; Li, Danni; Peng, Ye; Wang, Xiaoke; Jia, Guorong; Su, Weiwei; Cheng, Chao; Yang, Jian; Zuo, Changjing
2018-05-29
Au nanoparticles (3.8 ± 0.6 nm) are assembled to sub-micrometer Au particles (186.3 ± 20.4 nm) and covered with adhesive polydopamine (PDA) as embolism beads (198.8 ± 23.2 nm). Radioactive iodine-125 is labeled to Au@PDA to introduce the function of intra-irradiation. For the therapeutic effects of Au@PDA- 125 I, Au particles sensitize the radiation to MHCC97H hepatoma cells and tumor-bearing mice. At the cellular level, after being treated with a relatively low-dose (5 Gy) γ-ray, Au-sensitized radiotherapy (RT) leads to an immediate increase of intracellular reactive oxygen species, accompanying with an increase of cell apoptosis. Due to the intra-irradiation, self-healing of RT-leaded DNA double-strand breakage is suppressed, inducing a further increase of cell apoptosis after RT treatment. Likewise, 3 cycles of sensitized RT leads to a valid control of tumor volume growth, but Au@PDA- 125 I has no harm or radioactive residual on or in the radiosensitive organs, including the thyroid, heart, lungs, liver, and spleen. Additionally, photons emitted from 125 I and high X-ray absorption of the Au element makes the beads suitable for single photon emission computed tomography/computed tomography (SPECT/CT) imaging. Therefore, as theranostic embolism beads, Au@PDA- 125 I can both enhance the therapeutic effects of external RT, and provide a real-time SPECT/CT monitoring of therapeutic time window. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The FAK scaffold inhibitor C4 disrupts FAK-VEGFR-3 signaling and inhibits pancreatic cancer growth
Kurenova, Elena; Liao, Jianqun; He, Di-Hua; Hunt, Darrell; Yemma, Michael; Bshara, Wiam; Seshadri, Mukund; Cance, William G.
2013-01-01
Even with successful surgical resection and perioperative chemotherapy and radiation, pancreatic ductal adenocarcinoma (PDA) has a high incidence of recurrence. Tumor cell survival depends on activation of signaling pathways that suppress the apoptotic stimuli of invasion and metastasis. Focal adhesion kinase (FAK) is a critical signaling molecule that has been implicated in tumor cell survival, invasion and metastasis. We have previously shown that FAK and vascular endothelial growth factor receptor 3 (VEGFR-3) are overexpressed in cancer cells and physically interact to confer a significant survival advantage. We subsequently identified a novel small molecule inhibitor C4 that targeted the VEGFR-3-FAK site of interaction. In this study, we have shown that C4 disrupted the FAK-VEGFR-3 complexes in PDA cells. C4 treatment caused dose-dependent dephosphorylation and inactivation of the VEGFR-3 and FAK, reduction in cell viability and proliferation, cell cycle arrest and apoptosis in PDA cells. C4 increased the sensitivity of tumor cells to gemcitabine chemotherapy in vitro that lead to apoptosis at nanomolar concentrations of both drugs. C4 reduced tumor growth in vivoin subcutaneous and orthotopic murine models of PDA. The drug alone at low dose, decreased tumor growth; however, concomitant administration with low dose of gemcitabine had significant synergistic effect and led to 70% tumor reduction. Combination of C4 with gemcitabine had a prolonged cytostatic effect on tumor growth after treatment withdrawal. Finally, we report an anecdotal case of stage IV pancreatic cancer treated with gemcitabine in combination with C4 that showed a significant clinical response in primary tumor and complete clinical response in liver metastasis over an eight month period. Taken together, these results demonstrate that targeting the scaffolding function of FAK with a small-molecule FAK-VEGFR-3 inhibitor can be an effective therapeutic strategy against PDA. PMID:24142503
The Thai Business Initiative in Rural Development (TBIRD): a new dimension in rural development.
Viravaidya, M
1990-04-01
The Population and Community Development Association (PDA) promotes family planning (FP) throughout Thailand through a community-based approach. The Thai government actively supports rural development. In 1986, 80% of Thailand's people who lived below the poverty line were in rural areas. The poverty line in rural areas is an annual per capita income of 3823 baht, or US $153; in urban areas, it is more. Since 1984, Thailand's gross domestic product (GDP) has increased by more than 50%. Per capita GDP has risen dramatically, also, with the success of FP efforts. This economic achievement, however, has not been shared by most of the Thai population. Incomes in the agriculture sector are far below those in the nonagricultural sector. The government and the nonprofit organizations, however, do not have skills. The corporate sector does have these skills. The Thailand Business Initiative in Rural Development (TBIRD) helps companies sponsor villages and aids them in developing business skills, whereupon income levels and local living standards are improved. Companies thus help in the employment transfer from agriculture to nonagriculture. There is a "one-company-one- village" formula. Company employees have the skills needed in the villages. They are directly involved. Since 1988, PDA has been working with companies in Thailand to help villages develop business skills. In Saraburi province, PDA and Volvo Swedish Motors have been aiding villagers to grow saplings and sell them to golf course and housing developers. In Ayutthaya Province, PDA and the same company are helping the residents with needlepoint and embroidery to supply a wedding dress manufacturing operation. These programs have succeeded. PDA wants to expand the program by September 1990, to include 50 companies. It is hoped that once the companies are comfortable with their relationship to the village, they will start associations with additional villages. PDA has established the "Ten Steps to Adopt a Village."
Koido, Shigeo; Homma, Sadamu; Okamoto, Masato; Takakura, Kazuki; Mori, Masako; Yoshizaki, Shinji; Tsukinaga, Shintaro; Odahara, Shunichi; Koyama, Seita; Imazu, Hiroo; Uchiyama, Kan; Kajihara, Mikio; Arakawa, Hiroshi; Misawa, Takeyuki; Toyama, Yoichi; Yanagisawa, Satoru; Ikegami, Masahiro; Kan, Shin; Hayashi, Kazumi; Komita, Hideo; Kamata, Yuko; Ito, Masaki; Ishidao, Takefumi; Yusa, Sei-Ichi; Shimodaira, Shigetaka; Gong, Jianlin; Sugiyama, Haruo; Ohkusa, Toshifumi; Tajiri, Hisao
2014-08-15
We performed a phase I trial to investigate the safety, clinical responses, and Wilms' tumor 1 (WT1)-specific immune responses following treatment with dendritic cells (DC) pulsed with a mixture of three types of WT1 peptides, including both MHC class I and II-restricted epitopes, in combination with chemotherapy. Ten stage IV patients with pancreatic ductal adenocarcinoma (PDA) and 1 patient with intrahepatic cholangiocarcinoma (ICC) who were HLA-positive for A*02:01, A*02:06, A*24:02, DRB1*04:05, DRB1*08:03, DRB1*15:01, DRB1*15:02, DPB1*05:01, or DPB1*09:01 were enrolled. The patients received one course of gemcitabine followed by biweekly intradermal vaccinations with mature DCs pulsed with MHC class I (DC/WT1-I; 2 PDA and 1 ICC), II (DC/WT1-II; 1 PDA), or I/II-restricted WT1 peptides (DC/WT1-I/II; 7 PDA), and gemcitabine. The combination therapy was well tolerated. WT1-specific IFNγ-producing CD4(+) T cells were significantly increased following treatment with DC/WT1-I/II. WT1 peptide-specific delayed-type hypersensitivity (DTH) was detected in 4 of the 7 patients with PDA vaccinated with DC/WT1-I/II and in 0 of the 3 patients with PDA vaccinated with DC/WT1-I or DC/WT1-II. The WT1-specific DTH-positive patients showed significantly improved overall survival (OS) and progression-free survival (PFS) compared with the negative control patients. In particular, all 3 patients with PDA with strong DTH reactions had a median OS of 717 days. The activation of WT1-specific immune responses by DC/WT1-I/II combined with chemotherapy may be associated with disease stability in advanced pancreatic cancer. ©2014 American Association for Cancer Research.
Watanabe, Keisuke; Luo, Yanping; Da, Tong; Scholler, John; Keith, Brian; Young, Regina M.; Sorsa, Suvi; Siurala, Mikko; Havunen, Riikka; Tähtinen, Siri; Hemminki, Akseli
2018-01-01
Pancreatic ductal adenocarcinoma (PDA) is characterized by its highly immunosuppressive tumor microenvironment (TME) that limits T cell infiltration and induces T cell hypofunction. Mesothelin-redirected chimeric antigen receptor T cell (meso-CAR T cell) therapy has shown some efficacy in clinical trials but antitumor efficacy remains modest. We hypothesized that combined meso-CAR T cells with an oncolytic adenovirus expressing TNF-α and IL-2 (Ad5/3-E2F-D24-TNFa-IRES-IL2, or OAd-TNFa-IL2) would improve efficacy. OAd-TNFa-IL2 enhanced the antitumor efficacy of meso-CAR T cells in human-PDA-xenograft immunodeficient mice and efficacy was associated with robustly increased tumor-infiltrating lymphocytes (TILs), enhanced and prolonged T cell function. Mice treated with parental OAd combined with meso-CAR T developed tumor metastasis to the lungs even if primary tumors were controlled. However, no mice treated with combined OAd-TNFa-IL2 and meso-CAR T died of tumor metastasis. We also evaluated this approach in a syngeneic mouse tumor model by combining adenovirus expressing murine TNF-α and IL-2 (Ad-mTNFa-mIL2) and mouse CAR T cells. This approach induced significant tumor regression in mice engrafted with highly aggressive and immunosuppressive PDA tumors. Ad-mTNFa-mIL2 increased both CAR T cell and host T cell infiltration to the tumor and altered host tumor immune status with M1 polarization of macrophages and increased dendritic cell maturation. These findings indicate that combining cytokine-armed oncolytic adenovirus to enhance the efficacy of CAR T cell therapy is a promising approach to overcome the immunosuppressive TME for the treatment of PDA. PMID:29618658
NASA Astrophysics Data System (ADS)
Zhang, Xinyuan; Nan, Xu; Shi, Wei; Sun, Yanan; Su, Huiling; He, Yuan; Liu, Xin; Zhang, Zhong; Ge, Dongtao
2017-07-01
For releasing both drug and heat to selected sites, a combination of chemotherapy and photothermal therapy in one system is a more effective way to destroy cancer cells than monotherapy. Graphene oxide (GO) with high drug-loading efficiency and near-infrared (NIR) absorbance has great potential in drug delivery and photothermal therapy, but it is difficult to load drugs with high solubility. Herein, we develop a versatile drug delivery nanoplatform based on GO for integrated chemotherapy and photothermal therapy by a facile method of simultaneous reduction and surface functionalization of GO with poly(dopamine) (PDA). Due to the excellent adhesion of PDA, both low and high solubility drugs can be encapsulated in the PDA-functionalized GO nanocomposite (rGO-PDA). The fabricated nanocomposite exhibits good biocompatibility, excellent photothermal performance, high drug loading capacity, an outstanding sustained release property, and efficient endocytosis. Moreover, NIR laser irradiation facilitates the release of loaded drugs from rGO-PDA. These features make the rGO-PDA nanocomposite achieve excellent in vivo synergistic antitumor therapeutic efficacy.
Non-Fouling Biodegradable Poly(ϵ-caprolactone) Nanofibers for Tissue Engineering.
Kostina, Nina Yu; Pop-Georgievski, Ognen; Bachmann, Michael; Neykova, Neda; Bruns, Michael; Michálek, Jiří; Bastmeyer, Martin; Rodriguez-Emmenegger, Cesar
2016-01-01
Poly(ϵ-caprolactone) (PCL) nanofibers are very attractive materials for tissue engineering (TE) due to their degradability and structural similarity to the extracellular matrix (ECM). However, upon exposure to biological media, their surface is rapidly fouled by proteins and cells, which may lead to inflammation and foreign body reaction. In this study, an approach for the modification of PCL nanofibers to prevent protein fouling from biological fluids and subsequent cell adhesion is introduced. A biomimetic polydopamine (PDA) layer was deposited on the surface of the PCL nanofibers and four types of antifouling polymer brushes were grown by surface-initiated atom transfer radical polymerization (SI-ATRP) from initiator moieties covalently attached to the PDA layer. Cell adhesion was assessed with mouse embryonic fibroblasts (MEFs). MEFs rapidly adhered and formed cell-matrix adhesions (CMAs) with PCL and PCL-PDA nanofibers. Importantly, the nanofibers modified with antifouling polymer brushes were able to suppress non-specific protein adsorption and thereby cell adhesion. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
CD40 Agonists Alter Tumor Stroma and Show Efficacy Against Pancreatic Carcinoma in Mice and Humans
Beatty, Gregory L.; Chiorean, Elena G.; Fishman, Matthew P.; Saboury, Babak; Teitelbaum, Ursina R.; Sun, Weijing; Huhn, Richard D.; Song, Wenru; Li, Dongguang; Sharp, Leslie L.; Torigian, Drew A.; O’Dwyer, Peter J.; Vonderheide, Robert H.
2012-01-01
Immunosuppressive tumor microenvironments can restrain antitumor immunity, particularly in pancreatic ductal adenocarcinoma (PDA). Because CD40 activation can reverse immune suppression and drive antitumor T cell responses, we tested the combination of an agonist CD40 antibody with gemcitabine chemotherapy in a small cohort of patients with surgically incurable PDA and observed tumor regressions in some patients. We reproduced this treatment effect in a genetically engineered mouse model of PDA and found unexpectedly that tumor regression required macrophages but not T cells or gemcitabine. CD40-activated macrophages rapidly infiltrated tumors, became tumoricidal, and facilitated the depletion of tumor stroma. Thus, cancer immune surveillance does not necessarily depend on therapy-induced T cells; rather, our findings demonstrate a CD40-dependent mechanism for targeting tumor stroma in the treatment of cancer. PMID:21436454
A conservative treatment of patent ductus arteriosus in very low birth weight infants.
Letshwiti, J B; Semberova, J; Pichova, K; Dempsey, E M; Franklin, O M; Miletin, J
2017-01-01
Treatment of the patent ductus arteriosus (PDA) in the preterm infant remains contentious. There are numerous options of the PDA management from early targeted treatment, late (symptomatic) treatment to no treatment at all. To evaluate a three different PDA management approaches in very low birth weight (VLBW) infants. A retrospective observational time series study of three cohorts of VLBW infants born between 2004 and 2011. Infants in Symptomatic Treatment Group (STG) were echocardiographically evaluated when clinical signs suggestive of a PDA were present and treated if a haemodynamically significant PDA was confirmed. Early Targeted Group (ETG) underwent echocardiography within the first 48h and infants received ibuprofen if a large PDA was present. Conservative Treatment Group (CTG) was screened by echocardiography on day seven of life; patients with PDA were managed with increased positive end expiratory pressure and fluid restriction as a first line intervention. The primary outcome was medical and surgical treatment in the three time periods. Secondary outcomes included mortality, severe periventricular and intraventricular haemorrhage, respiratory distress syndrome and chronic lung disease. There were 138 infants diagnosed with PDA; 52 infants in STG, 52 infants in ETG and 34 infants in CTG. Ibuprofen therapy and ligation were less frequent in CTG. There was significantly decreased incidence of chronic lung disease in CTG compared to STG (18% vs. 51%; p=0.003) and to ETG (18% vs. 46%; p=0.02). There was no difference in the other short term outcomes. Conservative treatment of persistent ductus arteriosus in VLBW infants is a feasible option and future randomized trials of conservative management are warranted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Polydopamine--a nature-inspired polymer coating for biomedical science.
Lynge, Martin E; van der Westen, Rebecca; Postma, Almar; Städler, Brigitte
2011-12-01
Polymer coatings are of central importance for many biomedical applications. In the past few years, poly(dopamine) (PDA) has attracted considerable interest for various types of biomedical applications. This feature article outlines the basic chemistry and material science regarding PDA and discusses its successful application from coatings for interfacing with cells, to drug delivery and biosensing. Although many questions remain open, the primary aim of this feature article is to illustrate the advent of PDA on its way to become a popular polymer for bioengineering purposes.
Besmer, Dahlia M.; Curry, Jennifer M.; Roy, Lopamudra D.; Tinder, Teresa L.; Sahraei, Mahnaz; Schettini, Jorge; Hwang, Sun-Il; Lee, Yong Y.; Gendler, Sandra J.; Mukherjee, Pinku
2011-01-01
MUC1 is over expressed and aberrantly glycosolated in >60% of pancreatic ductal adenocarcinomas. The functional role of MUC1 in pancreatic cancer has yet to be fully elucidated due to a dearth of appropriate models. In the present study, we have generated mouse models that spontaneously develop pancreatic ductal adenocarcinoma (KC), which are either Muc1-null (KCKO) or express human MUC1 (KCM). We show that KCKO mice have significantly slower tumor progression and rates of secondary metastasis, compared to both KC and KCM. Cell lines derived from KCKO tumors have significantly lower tumorigenic capacity compared to cells from KCM tumors. Therefore, mice with KCKO tumors had a significant survival benefit compared to mice with KCM tumors. In vitro, KCKO cells have reduced proliferation and invasion and failed to respond to epidermal growth factor (EGF), platelet-derived growth factor (PDGF), or matrix metalloproteinase-9 (MMP9). Further, significantly fewer KCKO cells entered the G2M phase of the cell cycle compared to the KCM cells. Proteomics and western blotting analysis revealed a complete loss of cdc-25c expression, phosphorylation of MAPK, as well as a significant decrease in Nestin and Tubulin α-2 chain expression in KCKO cells. Treatment with a MEK1/2 inhibitor, U0126, abrogated the enhanced proliferation of the KCM cells but had minimal effect on KCKO cells, suggesting that MUC1 is necessary for MAPK activity and oncogenic signaling. This is the first study to utilize a Muc1-null PDA mouse in order to fully elucidate the oncogenic role of MUC1, both in vivo and in vitro. PMID:21558393
Zhang, Kun; Bai, Yuxin; Wang, Xiaofeng; Li, Qian; Guan, Fangxia; Li, Jingan
2017-08-01
Esophageal cancer is difficult to cure globally and possesses high mortality rate, and it is generally accepted that palliative care such as stent implantation is the main therapy method for esophageal cancer in later period. However, the restenosis caused by tumor cells and inflammatory cells seriously interferes the stent clinical application and limits its long-term services. To solve this problem, series of drug delivery stents were developed and proven rather effective in the early stage of implantation, but more serious restenosis occurred after the drug delivery was over, which endangered the patients' life. Therefore, endowing the esophageal stent continuous anti-cancer function become an ideal strategy for inhibiting the restenosis. In this contribution, the functional layer composed of polydopamine (PDA) and Poly-ethylenimine (PEI) with series of molecular weights (MW, 1.8 × 10 3 , 1 × 10 4 , 2.5 × 10 4 and 7 × 10 4 Da) were fabricated onto the esophageal stent material 317L stainless steel (317L SS) surface. The surface characterization including amine quantitative, atomic force microscopy (AFM) and water contact angle measurement indicated successful preparation of the PDA/PEI layer. The Eca109 cells culture results proved that the PDA/PEI layers significantly improve Eca109 cells apoptosis and necrosis, suggesting excellent anti-cancer function. In addition, we also found that the anti-cancer function of the PDA/PEI layers was positively correlated to the immobilized PEIs' MW. All the results demonstrated the potential application of the PDA/PEI layers on the surface modification of esophageal stent for continuous anti-cancer function. It is generally accepted that the restenosis caused by tumor cells seriously interferes the esophageal stent clinical application. Thus, endowing the esophageal stent continuous anti-cancer function is the ideal strategy for inhibiting the restenosis. In this work, we fabricated functional layers composed of polydopamine (PDA) and Poly-ethylenimine (PEI) with series of molecular weights (MW, 1.8 × 10 3 , 1 × 10 4 , 2.5 × 10 4 and 7 × 10 4 Da) onto the esophageal stent material 317L stainless steel (317L SS) surface to inhibit the tumor cells growth, and this function was related to the PEIs' molecular weights. The functional PDA/PEI layers were expected potentially applied for surface modification of esophageal stent materials.
Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George
2016-06-01
The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcomes compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of preinvasive foci. We investigated the effects of radiation therapy in p48(Cre);LSL-Kras(G12D) (KC) and p48(Cre);LSLKras(G12D);LSL-Trp53(R172H) (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony-stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2 to 12 Gy and analyzed by flow cytometry. Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from radiation treated invasive and preinvasive pancreatic tumors had an immune-suppressive, M2-like phenotype compared with control mice. Pancreata from mice exposed to radiation had fewer CD8(+) T cells than controls, and greater numbers of CD4(+) T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. A neutralizing antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Radiation treatment causes macrophages murine PDA to acquire an immune-suppressive phenotype and disabled T-cell-mediated anti-tumor responses. MCSF blockade negates this effect, allowing radiation to have increased efficacy in slowing tumor growth. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.
Bailey, Robert A; Pfeifer, Michael; Shillington, Alicia C; Harshaw, Qing; Funnell, Martha M; VanWingen, Jeffrey; Col, Nanada
2016-01-14
Patients with type 2 diabetes (T2DM) often have poor glycemic control on first-line pharmacologic therapy and require treatment intensification. Intensification decisions can be difficult because of many available options and their many benefits and risks. The American Diabetes Association recommends patient-centered, evidence-based tools supporting shared decision-making between patients and clinicians. We developed a patient decision aid (PDA) targeting decisions about treatment intensification for T2DM. Our objective was to determine the effectiveness of this PDA for patients with T2DM on metformin who require treatment intensification. This study was a pragmatic randomized controlled trial conducted in 27 US primary care and endocrinology clinics. Subjects were English-speaking adults with T2DM receiving metformin with persistent hyperglycemia who were recommended to consider medication intensification. Subjects were randomized to receive either the PDA or usual care (UC). Main outcome measures were change in knowledge, decisional self-efficacy, and decisional conflict. Of 225 subjects enrolled, 114 were randomized to the PDA and 111 to UC. Mean [SD] age was 52 [1] years, time since T2DM diagnosis was 6 [+/-6] years, 45.3% were male, and most (55.5%) were non-Caucasian. Compared to UC, PDA users had significantly larger knowledge gains (35.0% [22.3] vs 9.9% [22.2]; P < 0.0001) and larger improvements in self-efficacy (3.7 [16.7] vs-3.9 [19.2]; P < 0.0001) and decisional conflict (-22.2 [20.6] vs-7.5 [16.6]; P < 0.0001). The PDA resulted in substantial and significant improvements in knowledge, decisional conflict and decisional self-efficacy. Decisional conflict scores after PDA use were within the range that correlates with effective decision-making. This PDA has the potential to facilitate shared-decision-making for patients with T2DM. NCT02110979.
Zhou, Yalei; Zhou, Jie; Wang, Feng; Yang, Haifeng
2018-05-01
Particles which bear tumor cell targeting and multimode imaging capabilities are promising in tumor diagnosis and cancer therapy. A simple and versatile method to fabricate gold/polydopamine-Methylene Blue@Bovine Serum Albumin-glutaraldehyde-Transferrin composite particles (Au/PDA-MB@BSA-GA-Tf NPs) for tumor cell targeting and fluorescence (FL) / surface-enhanced Raman scattering (SERS) dual-modal imaging were reported in this work. Polydopamine (PDA) spheres played an important role in gold ion reduction, gold nanoparticle (Au NPs) binding and methylene blue (MB) adsorption, MB were employed as both fluorescence label and Raman reporter. In addition, glutaraldehyde (GA) crosslinked bovine serum albumin (BSA) in the outer layer of Au/PDA-MB nanoparticles can prevent MB from dissociation and leakage. The composite nanoparticles were further conjugated with transferrin (Tf) to target transferrin receptor (TfR)-overexpressed cancer cells. The targeting ability as well as the intracellular location of the probe was investigated through SERS mapping and fluorescence imaging. Their excellent biocompatibility was demonstrated by low cytotoxicity against breast cancer cell (4T1 cell). Copyright © 2018 Elsevier B.V. All rights reserved.
Genetic Diversity of Pancreatic Ductal Adenocarcinoma and Opportunities for Precision Medicine.
Knudsen, Erik S; O'Reilly, Eileen M; Brody, Jonathan R; Witkiewicz, Agnieszka K
2016-01-01
Patients with pancreatic ductal adenocarcinoma (PDA) have a poor prognosis despite new treatments; approximately 7% survive for 5 years. Although there have been advances in systemic, primarily cytotoxic, therapies, it has been a challenge to treat patients with PDA using targeted therapies. Sequence analyses have provided a wealth of information about the genetic features of PDA and have identified potential therapeutic targets. Preclinical and early-phase clinical studies have found specific pathways could be rationally targeted; it might also be possible to take advantage of the genetic diversity of PDAs to develop therapeutic agents. The genetic diversity and instability of PDA cells have long been thought of as obstacles to treatment, but are now considered exploitable features. We review the latest findings in pancreatic cancer genetics and the promise of targeted approaches in PDA therapy. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.
Matrix control of pancreatic cancer: New insights into fibronectin signaling.
Topalovski, Mary; Brekken, Rolf A
2016-10-10
Pancreatic ductal adenocarcinoma (PDA) is a highly metastatic disease that resists most current therapies. A defining characteristic of PDA is an intense fibrotic response that promotes tumor cell invasion and chemoresistance. Efforts to understand the complex relationship between the tumor and its extracellular network and to therapeutically perturb tumor-stroma interactions are ongoing. Fibronectin (FN), a provisional matrix protein abundant in PDA stroma but not normal tissues, supports metastatic spread and chemoresistance of this deadly disease. FN also supports angiogenesis, which is required for even hypovascular tumors such as PDA to develop and progress. Targeting components of the tumor stroma, such as FN, can effectively reduce tumor growth and spread while also enhancing delivery of chemotherapy. Here, we review the molecular mechanisms by which FN drives angiogenesis, metastasis and chemoresistance in PDA. In light of these new findings, we also discuss therapeutic strategies to inhibit FN signaling. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
MSuPDA: A memory efficient algorithm for sequence alignment.
Khan, Mohammad Ibrahim; Kamal, Md Sarwar; Chowdhury, Linkon
2015-01-16
Space complexity is a million dollar question in DNA sequence alignments. In this regards, MSuPDA (Memory Saving under Pushdown Automata) can help to reduce the occupied spaces in computer memory. Our proposed process is that Anchor Seed (AS) will be selected from given data set of Nucleotides base pairs for local sequence alignment. Quick Splitting (QS) techniques will separate the Anchor Seed from all the DNA genome segments. Selected Anchor Seed will be placed to pushdown Automata's (PDA) input unit. Whole DNA genome segments will be placed into PDA's stack. Anchor Seed from input unit will be matched with the DNA genome segments from stack of PDA. Whatever matches, mismatches or Indel, of Nucleotides will be POP from the stack under the control of control unit of Pushdown Automata. During the POP operation on stack it will free the memory cell occupied by the Nucleotide base pair.
King, Kathryn; Wiebe, Michael
2011-01-01
CONFERENCE PROCEEDING Proceedings of the PDA/FDA Adventitious Viruses in Biologics: Detection and Mitigation Strategies Workshop in Bethesda, MD, USA; December 1-3, 2010 Guest Editors: Arifa Khan (Bethesda, MD), Patricia Hughes (Bethesda, MD) and Michael Wiebe (San Francisco, CA).
Roushdy, Alaa; Fiky, Azza El; Din, Dina Ezz El
2012-07-01
To determine the feasibility and accuracy of real time 3D echocardiography (RT3DE) in determining the dimensions and anatomical type of the patent ductus arteriosus (PDA). The study included 42 pediatric patients with a mean age of 3.6 years (ranging from 2 months to 14 years) who were referred for elective percutaneous PDA closure. All patients underwent full 2D echocardiogram as well as RT3DE with off line analysis using Q lab software within 6 h from their angiograms. The PDA was studied as regard the anatomical type, length of the duct as well as the ampulla and the pulmonary end of the PDA. Data obtained by RT3DE was compared against 2D echocardiogram and the gold standard angiography. Offline analysis of the PDA was feasible in 97.6% of the cases while determination of the anatomical type using gated color flow 3D acquisitions was achieved in 78.5% of the cases. The pulmonary end of the duct was rather elliptical using 3D echocardiogram. There was significant difference between the pulmonary end measured by 3D echocardiogram and angiography (P < 0.001). There was no significant difference between either the length or the ampulla of the PDA measured by 3D echocardiogram and that measured by angiography (P value = 0.325 and 0.611, respectively). There was a good agreement between both 2D or 3D echocardiogram and angiography in determining the anatomical type of the PDA (K = 0.744 and 0.773, respectively). However 3D echocardiogram could more accurately determine type A and type E ductus compared to 2D echocardiogram. 3D echocardiogram was more accurate than 2D echocardiogram in determining the length and the ampulla of the PDA. The morphologic assessment of the PDA using gated 3D color flow was achieved in 78.5% of the patients. Nevertheless the use of 3D echocardiogram in assessment of small vascular structures like PDA in children with rapid heart rates is still of limited clinical value.
Transcriptional control of the autophagy-lysosome system in pancreatic cancer
Perera, Rushika M.; Stoykova, Svetlana; Nicolay, Brandon N.; Ross, Kenneth N.; Fitamant, Julien; Boukhali, Myriam; Lengrand, Justine; Deshpande, Vikram; Selig, Martin K.; Ferrone, Cristina R.; Settleman, Jeff; Stephanopoulos, Gregory; Dyson, Nicholas J.; Zoncu, Roberto; Ramaswamy, Sridhar; Haas, Wilhelm; Bardeesy, Nabeel
2016-01-01
Activation of cellular stress response pathways to maintain metabolic homeostasis is emerging as a critical growth and survival mechanism in many cancers1. The pathogenesis of pancreatic ductal adenocarcinoma (PDA) requires high levels of autophagy2–4, a conserved self-degradative process5. However, the regulatory circuits that activate autophagy and reprogram PDA cell metabolism are unknown. We now show that autophagy induction in PDA occurs as part of a broader transcriptional program that coordinates activation of lysosome biogenesis and function, and nutrient scavenging, mediated by the MiT/TFE family transcription factors. In PDA cells, the MiT/TFE proteins6 – MITF, TFE3 and TFEB – are decoupled from regulatory mechanisms that control their cytoplasmic retention. Increased nuclear import in turn drives the expression of a coherent network of genes that induce high levels of lysosomal catabolic function essential for PDA growth. Unbiased global metabolite profiling reveals that MiT/TFE-dependent autophagy-lysosomal activation is specifically required to maintain intracellular amino acid (AA) pools. These results identify the MiT/TFE transcription factors as master regulators of metabolic reprogramming in pancreatic cancer and demonstrate activation of clearance pathways converging on the lysosome as a novel hallmark of aggressive malignancy. PMID:26168401
Xiao, L Z; Ichikawa, S
1998-03-16
Mutagenic interactions between X-rays and two promutagens, o-phenylenediamine (PDA) and N-nitrosodimethylamine (DMN), were studied in the stamen hairs of Tradescantia clone BNL 4430, a blue/pink heterozygote. The young inflorescence-bearing shoots with roots of this clone cultivated in a nutrient solution circulating growth chamber were used as tester plants. After determining dose-response curves for X-rays. PDA and DMN, combined treatments with PDA or DMN and X-rays were conducted, exposing acutely to X-rays 20 h before starting, at the midpoint of, or 20 h after completing the PDA or DMN treatments for 4 h. Clear synergistic effects in inducing somatic pink mutations were detected when X-rays were irradiated before the PDA or DMN treatments, resembling those confirmed earlier between maleic hydrazide (MH) and X-rays. On the contrary, clear antagonistic effects were observed when X-rays were given after the PDA or DMN treatments, also resembling those between MH and X-rays. When X-rayed at the midpoint of the PDA or DMN treatments, merely additive and synergistic effects were observed, respectively, differing from the antagonistic effects between MH and X-rays. The mutagenic synergisms detected were considered to be the results of interactions between DNA strand breaks (and the resultant chromosome breaks) induced by X-rays and those by PDA or DMN, whereas the mutagenic antagonisms observed were presumed to be due to X-ray-caused inhibition of the activation of PDA and DMN in the stamen-hair cells. The time periods required for penetrations into floral tissues and/or activations into mutagens seem different among PDA, DMN and MH. Copyright 1998 Elsevier Science B.V.
Tiriac, Herve; Bucobo, Juan Carlos; Tzimas, Demetrios; Grewel, Suman; Lacomb, Joseph F; Rowehl, Leahana M; Nagula, Satish; Wu, Maoxin; Kim, Joseph; Sasson, Aaron; Vignesh, Shivakumar; Martello, Laura; Munoz-Sagastibelza, Maria; Somma, Jonathan; Tuveson, David A; Li, Ellen; Buscaglia, Jonathan M
2018-06-01
Pancreatic cancer organoids are tumor models of individualized human pancreatic ductal adenocarcinoma (PDA), created from surgical specimens and used for personalized treatment strategies. Unfortunately, most patients with PDA are not operative candidates. Creation of human PDA organoids at the time of initial tumor diagnosis is therefore critical. Our aim was to assess the feasibility of creating human PDA organoids by EUS fine-needle biopsy (EUS-FNB) sampling in patients with PDA. In this prospective clinical trial in patients referred to evaluate a pancreatic mass, EUS-FNA was performed for initial onsite diagnosis. Two additional needle passes were performed with a 22-gauge FNB needle for organoid creation. Primary outcome was successful isolation of organoids within 2 weeks of EUS-FNB sampling (P0, no passages), confirmed by organoid morphology and positive genotyping. Thirty-seven patients with 38 PDA tumors were enrolled. Successful isolation of organoids (P0) was achieved in 33 of 38 tumors (87%). Establishment of PDA organoid lines for ≥5 passages of growth (P5, five passages) was reached in 25 of 38 tumors (66%). In the single patient with successful P5 FNB sampling-derived and P5 surgically derived organoids, there was identical matching of specimens. There were no serious adverse events. Two patients developed bleeding at the EUS-FNB puncture site requiring hemostasis clips. Pancreatic cancer organoids can be successfully and rapidly created by means of EUS-FNB sampling using a 22-gauge needle at the time of initial diagnosis. Successful organoid generation is essential for precision medicine in patients with pancreatic cancer in whom most are not surgically resectable. (Clinical trial registration number: NCT03140592.). Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Xiang, Yuqian; Pang, Youyou; Jiang, Xiaomei; Huang, Jie; Xi, Fengna; Liu, Jiyang
2018-01-01
Absorbent materials integrated with superhydrophobicity, superoleophilicity and flame-retardancy are highly desired in the adsorption/removal of flammable oils/organic compounds as well as reducing the risk of fire and explosion. Here, one-step fabrication of novel superhydrophobic and superoleophilic sponge with outstanding absorbency and flame-retardancy was presented. Using raw melamine (ME) sponge as the supporting matrix, the formation of polydopamine (PDA) nanoaggregates via in-situ self-polymerization of high-concentrated dopamine and the covalent grafting of hydrophobic n-dodecylthiol (DT) onto PDA were combined in a feasible alkaline water/ethanol medium. As investigated by scanning electron microscopy (SEM) and X-ray energy-dispersive spectroscopy (EDS), the as-prepared ME/PDA/DT sponge possessed hierarchical structure with submicron PDA nanoaggregates containing DT motif (low surface energy) on 3D interconnected porous network. It exhibited superhydrophobic (water contact angle 157.7°) and superoleophilic (oily/organic solvent contact angle 0° properties. Owing to the highly porous structure, superhydrophobic property, chemical and mechanical stability, the ME/PDA/DT sponge exhibited outstanding absorbency properties of oily organic solvents including fast absorption kinetics, high absorption capacity, and easy reusability. Also, the ME/PDA/DT sponge could be used for one-line continuous organic solvent/water separation. More interestingly, the ME/PDA/DT sponge demonstrated improved flame-retardant property as compared to the intrinsic flame-retardant nature of the raw melamine sponge. Consequently, the risk of fire and explosion was expected to reduce when the fabricated sponge was used as an absorbent for flammable oils and organic compounds. The ease of the one-step superhydrophobic/superoleophilic modification and the promising feature of the obtained materials exhibit great potential for application in oils/organic solvents clean-up.
Isoform-Specific Upregulation of Palladin in Human and Murine Pancreas Tumors
Goicoechea, Silvia M.; Bednarski, Brian; Stack, Christianna; Cowan, David W.; Volmar, Keith; Thorne, Leigh; Cukierman, Edna; Rustgi, Anil K.; Brentnall, Teresa; Hwang, Rosa F.; McCulloch, Christopher A. G.; Yeh, Jen Jen; Bentrem, David J.; Hochwald, Steven N.; Hingorani, Sunil R.
2010-01-01
Pancreatic ductal adenocarcinoma (PDA) is a lethal disease with a characteristic pattern of early metastasis, which is driving a search for biomarkers that can be used to detect the cancer at an early stage. Recently, the actin-associated protein palladin was identified as a candidate biomarker when it was shown that palladin is mutated in a rare inherited form of PDA, and overexpressed in many sporadic pancreas tumors and premalignant precursors. In this study, we analyzed the expression of palladin isoforms in murine and human PDA and explored palladin's potential use in diagnosing PDA. We performed immunohistochemistry and immunoblot analyses on patient samples and tumor-derived cells using an isoform-selective monoclonal antibody and a pan-palladin polyclonal antibody. Immunoblot and real-time quantitative reverse transcription-PCR were used to quantify palladin mRNA levels in human samples. We show that there are two major palladin isoforms expressed in pancreas: 65 and 85–90 kDa. The 65 kDa isoform is expressed in both normal and neoplastic ductal epithelial cells. The 85–90 kDa palladin isoform is highly overexpressed in tumor-associated fibroblasts (TAFs) in both primary and metastatic tumors compared to normal pancreas, in samples obtained from either human patients or genetically engineered mice. In tumor-derived cultured cells, expression of palladin isoforms follows cell-type specific patterns, with the 85–90 kDa isoform in TAFs, and the 65 kDa isoform predominating in normal and neoplastic epithelial cells. These results suggest that upregulation of 85–90 kDa palladin isoform may play a role in the establishment of the TAF phenotype, and thus in the formation of a desmoplastic tumor microenvironment. Thus, palladin may have a potential use in the early diagnosis of PDA and may have much broader significance in understanding metastatic behavior. PMID:20436683
Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng
2016-01-05
Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo.
NASA Astrophysics Data System (ADS)
Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng
2016-01-01
Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo.
Wang, Zhenming; Jia, Zhanrong; Jiang, Yanan; Li, Pengfei; Han, Lu; Lu, Xiong; Ren, Fuzeng; Wang, Kefeng; Yuan, Huiping
2017-08-03
The assembly of nano-building blocks is an effective way to produce artificial extracellular matrix microenvironments with hierarchical micro/nano structures. However, it is hard to assemble different types of nano-building blocks, to form composite coatings with multiple functions, by traditional layer-by-layer (LbL) self-assembly methods. Inspired by the mussel adhesion mechanism, we developed polydopamine (PDA)-decorated bovine serum albumin microspheres (BSA-MS) and nano-hydroxyapatite (nano-HA), and assembled them to form bioactive coatings with micro/nano structures encapsulating bone morphogenetic protein-2 (BMP-2). First, PDA-decorated nano-HA (nano-pHA) was obtained by oxidative polymerization of dopamine on nano-HA. Second, BMP-2-encapsulated BSA microspheres were prepared through desolvation, and then were also decorated by PDA (pBSA-MS). Finally, the nano-pHA and pBSA-MS were assembled using the adhesive properties of PDA. Bone marrow stromal cell cultures and in vivo implantation, showed that the pHA/pBSA (BMP-2) coatings can promote cell adhesion, proliferation, and benefited for osteoinductivity. PDA decoration was also applied to assemble various functional nanoparticles, such as nano-HA, polystyrene, and Fe 3 O 4 nanoparticles. In summary, this study provides a novel strategy for the assembly of biofunctional nano-building blocks, which surpasses traditional LbL self-assembly of polyelectrolytes, and can find broad applications in bioactive agents delivery or multi-functional coatings.
MSuPDA: A Memory Efficient Algorithm for Sequence Alignment.
Khan, Mohammad Ibrahim; Kamal, Md Sarwar; Chowdhury, Linkon
2016-03-01
Space complexity is a million dollar question in DNA sequence alignments. In this regard, memory saving under pushdown automata can help to reduce the occupied spaces in computer memory. Our proposed process is that anchor seed (AS) will be selected from given data set of nucleotide base pairs for local sequence alignment. Quick splitting techniques will separate the AS from all the DNA genome segments. Selected AS will be placed to pushdown automata's (PDA) input unit. Whole DNA genome segments will be placed into PDA's stack. AS from input unit will be matched with the DNA genome segments from stack of PDA. Match, mismatch and indel of nucleotides will be popped from the stack under the control unit of pushdown automata. During the POP operation on stack, it will free the memory cell occupied by the nucleotide base pair.
Mohd Daud, Nurizzati; Saeful Bahri, Ihda Fithriyana; Nik Malek, Nik Ahmad Nizam; Hermawan, Hendra; Saidin, Syafiqah
2016-09-01
Chlorhexidine (CHX) is known for its high antibacterial substantivity and is suitable for use to bio-inert medical devices due to its long-term antibacterial efficacy. However, CHX molecules require a crosslinking film to be stably immobilized on bio-inert metal surfaces. Therefore, polydopamine (PDA) was utilized in this study to immobilize CHX on the surface of 316L type stainless steel (SS316L). The SS316L disks were pre-treated, modified with PDA film and immobilized with different concentrations of CHX (10mM-50mM). The disks were then subjected to various surface characterization analyses (ATR-FTIR, XPS, ToF-SIMS, SEM and contact angle measurement) and tested for their cytocompatibility with human skin fibroblast (HSF) cells and antibacterial activity against Escherichia coli and Staphylococcus aureus. The results demonstrated the formation of a thin PDA film on the SS316L surface, which acted as a crosslinking medium between the metal and CHX. CHX was immobilized via a reduction process that covalently linked the CHX molecules with the functional group of PDA. The immobilization of CHX increased the hydrophobicity of the disk surfaces. Despite this property, a low concentration of CHX optimized the viability of HSF cells without disrupting the morphology of adherent cells. The immobilized disks also demonstrated high antibacterial efficacy against both bacteria, even at a low concentration of CHX. This study demonstrates a strong beneficial effect of the crosslinked PDA film in immobilizing CHX on bio-inert metal, and these materials are applicable in medical devices. Specifically, the coating will restrain bacterial proliferation without suffocating nearby tissues. Copyright © 2016 Elsevier B.V. All rights reserved.
The pancreatic niche inhibits the effectiveness of sunitinib treatment of pancreatic cancer
Martínez-Bosch, Neus; Guerrero, Pedro Enrique; Moreno, Mireia; José, Anabel; Iglesias, Mar; Munné-Collado, Jessica; Anta, Héctor; Gibert, Joan; Orozco, Carlos Alberto; Vinaixa, Judith; Fillat, Cristina; Viñals, Francesc; Navarro, Pilar
2016-01-01
Current treatments for pancreatic ductal adenocarcinoma (PDA) are ineffective, making this the 4th leading cause of cancer deaths. Sunitinib is a broad-spectrum inhibitor of tyrosine kinase receptors mostly known for its anti-angiogenic effects. We tested the therapeutic effects of sunitinib in pancreatic cancer using the Ela-myc transgenic mouse model. We showed that Ela-myc pancreatic tumors express PDGFR and VEGFR in blood vessels and epithelial cells, rendering these tumors sensitive to sunitinib by more than only its anti-angiogenic activity. However, sunitinib treatment of Ela-myc mice with either early or advanced tumor progression had no impact on either survival or tumor burden. Further histopathological characterization of these tumors did not reveal differences in necrosis, cell differentiation, angiogenesis, apoptosis or proliferation. In stark contrast, in vitro sunitinib treatment of Ela-myc– derived cell lines showed high sensitivity to the drug, with increased apoptosis and reduced proliferation. Correspondingly, subcutaneous tumors generated from these cell lines completely regressed in vivo after sunitinib treatments. These data point at the pancreatic tumor microenvironment as the most likely barrier preventing sunitinib treatment efficiency in vivo. Combined treatments with drugs that disrupt tumor fibrosis may enhance sunitinib therapeutic effectiveness in pancreatic cancer treatment. PMID:27374084
Daley, Donnele; Mani, Vishnu R.; Mohan, Navyatha; Akkad, Neha; Ochi, Atsuo; Heindel, Daniel W.; Lee, Ki Buom; Zambirinis, Constantinos P.; Pandian, Gautam S.D. Balasubramania; Savadkar, Shivraj; Torres-Hernandez, Alejandro; Nayak, Shruti; Wang, Ding; Hundeyin, Mautin; Diskin, Brian; Aykut, Berk; Werba, Gregor; Barilla, Rocky M.; Rodriguez, Robert; Chang, Steven; Gardner, Lawrence; Mahal, Lara K.; Ueberheide, Beatrix; Miller, George
2017-01-01
The progression of pancreatic oncogenesis requires immune-suppressive inflammation in cooperation with oncogenic mutations. However, the drivers of intra-tumoral immune tolerance are uncertain. Dectin-1 is an innate immune receptor critical in anti-fungal immunity, but its role in sterile inflammation and oncogenesis is not well-defined. Further, non-pathogen-derived ligands for Dectin-1 have not been characterized. We found that Dectin-1 is highly expressed on macrophages in pancreatic ductal adenocarcinoma (PDA). Dectin-1 ligation accelerated PDA, whereas Dectin-1 deletion or blockade of its downstream signaling was protective. We found that Dectin-1 ligates the lectin Galectin-9 in the PDA tumor microenvironment resulting in tolerogenic macrophage programming and adaptive immune suppression. Upon interruption of the Dectin-1–Galectin-9 axis, CD4+ and CD8+ T cells – which are dispensable to PDA progression in hosts with an intact signaling axis – become reprogrammed into indispensable mediators of anti-tumor immunity. These data suggest that targeting Dectin-1 signaling is an attractive strategy for the immunotherapy of PDA. PMID:28394331
Zhou, Ping; Deng, Yi; Lyu, Beier; Zhang, Ranran; Zhang, Hai; Ma, Hongwei; Lyu, Yalin; Wei, Shicheng
2014-01-01
Polydopamine (PDA) coating provides a promising approach for immobilization of biomolecules onto almost all kinds of solid substrates. However, the deposition kinetics of PDA coating as a function of temperature and reaction method is not well elucidated. Since dopamine self-polymerization usually takes a long time, therefore, rapid-formation of PDA film becomes imperative for surface modification of biomaterials and medical devices. In the present study, a practical method for preparation of rapidly-deposited PDA coating was developed using a uniquely designed device, and the kinetics of dopamine self-polymerization was investigated by QCM sensor system. It was found that high temperature and vigorous stirring could dramatically speed up the formation of PDA film on QCM chip surface. Surface characterization, BSA binding study, cell viability assay and antibacterial test demonstrates that the polydopamine coating after polymerization for 30 min by our approach exhibits similar properties to those of 24 h counterpart. The method has a great potential for rapid-deposition of polydopamine films to modify biomaterial surfaces. PMID:25415328
Zhang, Xuzhu; Du, Fang; Huang, Jin; Lu, Wei; Liu, Shiyuan; Yu, Jiahui
2012-12-01
This research is aimed to develop a biodegradable micelle delivery system with sheddable poly (ethylene glycol) shell to achieve the reduction-triggered intracellular sustained release of 6-mercaptopurine (6-MP) and decreased toxicity. Firstly, the amino-disulfide linked poly (ethylene glycol) monomethyl ether (mPEG-SS-NH(2)) was synthesized by the amidation reaction between cystamine and active ester of mPEG and p-nitrophenyl chloroformate (p-NPC) (mPEG-NPC). And then, the five-member rings in poly (l-succinimide) (PSI) were successively opened by mPEG-SS-NH(2) and 2-(pyridyldithio)-ethylamine (PDA) to produce the graft copolymer of mPEG-SS-NH-graft-PAsp-PDA. To avoid the drug initial burst, 6-MP was covalently conjugated with mPEG-SS-NH-graft-PAsp-PDA by thoil-disulfide exchange reaction to give the resultant product mPEG-SS-NH-graft-PAsp-MP. The product was found to form spherical micelles in aqueous media because of its amphiphilic nature with average particle size of 160 nm measured by dynamic light scattering (DLS). It was found that the mPEG-SS-NH-graft-PAsp-MP micelles, though stable in phosphate buffer solution (PBS), were prone to aggregation in the presence of dithiothreitol (DTT). The in vitro drug release studies revealed the release of 6-MP were distinct from the conventional micelles whose drugs loaded by physical encapsulation. Sustained release profile of 6-MP over 85 h was found in the presence of DTT (40 mM) simulating the intracellular condition while minimal drug release was observed within 24h at the level of DTT corresponding to extracellular environment. Remarkably, the cell viability results showed there was essential decrease of cytotoxicity to HL-60 cell line compared to free 6-MP. Copyright © 2012 Elsevier B.V. All rights reserved.
Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng
2016-01-01
Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo. PMID:26728448
Polydopamine-coated liposomes as pH-sensitive anticancer drug carriers.
Zong, Wei; Hu, Ying; Su, Yingchun; Luo, Nan; Zhang, Xunan; Li, Qingchuan; Han, Xiaojun
2016-05-01
Stimuli-responsive drug carriers are considered to play important roles in chemotherapy. We fabricated pH-sensitive polydopamine-protected liposomes (liposome@PDA) drug delivery systems, which were characterised with microscope, scanning electron microscope (SEM), UV-vis spectrometer and Fourier transform infrared (FTIR) technieques. The typical chemotherapeutic agent, 5-fluorouracil (5-FU), was loaded into liposome@PDA capsules. The maximum release percentages of 5-FU are 3.2%, 29.5%, 52.7%, 76.7% in the solution with pH 7.42, 6.87, 4.11 and 3.16, respectively. The in vitro cell cytotoxity experiments were carried out using 5-FU-loaded capsules at pH 6.87 solution, which simulate the true pH around cancerous cells. At 1.5 μM concentration, the free 5-FU, 5-FU-loaded liposome capsules and 5-FU-loaded capsules showed the cell viability of 50.56%, 22.66% and 21.63%, respectively. It confirms that drug-loaded capsules performed better than free drug. The results demonstrate the great potential of liposome@PDA capsules as carriers in biomedical applications.
Tinder, Teresa L; Subramani, Durai B; Basu, Gargi D; Bradley, Judy M; Schettini, Jorge; Million, Arefayene; Skaar, Todd; Mukherjee, Pinku
2008-09-01
MUC1, a membrane tethered mucin glycoprotein, is overexpressed and aberrantly glycosylated in >80% of human ductal pancreatic adenocarcinoma. However, the role of MUC1 in pancreatic cancer has been elusive, partly due to the lack of an appropriate model. We report the characterization of a novel mouse model that expresses human MUC1 as a self molecule (PDA.MUC1 mice). Pancreatic tumors arise in an appropriate MUC1-tolerant background within an immune-competent host. Significant enhancement in the development of pancreatic intraepithelial preneoplastic lesions and progression to adenocarcinoma is observed in PDA.MUC1 mice, possibly due to increased proliferation. Tumors from PDA.MUC1 mice express higher levels of cyclooxygenase-2 and IDO compared with PDA mice lacking MUC1, especially during early stages of tumor development. The increased proinflammatory milieu correlates with an increased percentage of regulatory T cells and myeloid suppressor cells in the pancreatic tumor and tumor draining lymph nodes. Data shows that during pancreatic cancer progression, MUC1-mediated mechanisms enhance the onset and progression of the disease, which in turn regulate the immune responses. Thus, the mouse model is ideally suited for testing novel chemopreventive and therapeutic strategies against pancreatic cancer.
Tinder, Teresa L.; Subramani, Durai B.; Basu, Gargi D.; Bradley, Judy M.; Schettini, Jorge; Million, Arefayene; Skaar, Todd
2008-01-01
MUC1, a membrane tethered mucin glycoprotein, is overexpressed and aberrantly glycosylated in >80% of human ductal pancreatic adenocarcinoma. However, the role of MUC1 in pancreatic cancer has been elusive, partly due to the lack of an appropriate model. We report the characterization of a novel mouse model that expresses human MUC1 as a self molecule (PDA.MUC1 mice). Pancreatic tumors arise in an appropriate MUC1-tolerant background within an immune competent host. Significant enhancement in the development of pancreatic intraepithelial pre-neoplastic lesions (PanINs) and progression to adenocarcinoma is observed in PDA.MUC1 mice, possibly due to increased proliferation. Tumors from PDA.MUC1 mice express higher levels of cyclooxygenase-2 and indoleamine 2,3, dioxygenase compared to PDA mice lacking MUC1, especially during early stages of tumor development. The increased pro-inflammatory milieu correlates with an increased percentage of regulatory T cells and myeloid suppressor cells in the pancreatic tumor and tumor draining lymph nodes. Data shows that during pancreatic cancer progression, MUC1-mediated mechanisms enhance the onset and progression of the disease which in turn regulate the immune responses. Thus, the mouse model is ideally-suited for testing novel chemopreventive and therapeutic strategies against pancreatic cancer. PMID:18713982
NASA Astrophysics Data System (ADS)
Ke, Yaotang; Garg, Bhaskar; Ling, Yong-Chien
2016-02-01
A novel label-free fluorescence `turn-on' nanosensor has been developed for highly selective and sensitive detection of phosphorylated species (Ps) in biological samples and living cells. The design strategy relies on the use of Ti4+-immobilized polydopamine (PDA) coated reduced graphene oxide (rGO@PDA-Ti4+) that serves as an attractive platform to bind riboflavin 5'-monophosphate molecules (FMNs) through ion-pair interactions between phosphate groups and Ti4+. The as-prepared rGO@PDA-Ti4+-FMNs (nanosensor), fluoresce only weakly due to the ineffective Förster resonance energy transfer between the FMNs and rGO@PDA-Ti4+. The experimental findings revealed that the microwave-assisted interaction of the nanosensor with α-, β-casein, ovalbumin, human serum, non-fat milk, egg white, and living cells (all containing Ps) releases FMNs (due to the high formation constant between phosphate groups and Ti4+), leading to an excellent fluorescence `turn-on' response. The fluorescence spectroscopy, confocal microscopy, and MALDI-TOF MS spectrometry were used to detect Ps both qualitatively and quantitatively. Under the optimized conditions, the nanosensor showed a detection limit of ca. 118.5, 28.9, and 54.8 nM for the tryptic digests of α-, β-casein and ovalbumin, respectively. Furthermore, the standard addition method was used as a bench-mark proof for phosphopeptide quantification in egg white samples. We postulate that the present quantitative assay for Ps holds tremendous potential and may pave the way to disease diagnostics in the near future.A novel label-free fluorescence `turn-on' nanosensor has been developed for highly selective and sensitive detection of phosphorylated species (Ps) in biological samples and living cells. The design strategy relies on the use of Ti4+-immobilized polydopamine (PDA) coated reduced graphene oxide (rGO@PDA-Ti4+) that serves as an attractive platform to bind riboflavin 5'-monophosphate molecules (FMNs) through ion-pair interactions between phosphate groups and Ti4+. The as-prepared rGO@PDA-Ti4+-FMNs (nanosensor), fluoresce only weakly due to the ineffective Förster resonance energy transfer between the FMNs and rGO@PDA-Ti4+. The experimental findings revealed that the microwave-assisted interaction of the nanosensor with α-, β-casein, ovalbumin, human serum, non-fat milk, egg white, and living cells (all containing Ps) releases FMNs (due to the high formation constant between phosphate groups and Ti4+), leading to an excellent fluorescence `turn-on' response. The fluorescence spectroscopy, confocal microscopy, and MALDI-TOF MS spectrometry were used to detect Ps both qualitatively and quantitatively. Under the optimized conditions, the nanosensor showed a detection limit of ca. 118.5, 28.9, and 54.8 nM for the tryptic digests of α-, β-casein and ovalbumin, respectively. Furthermore, the standard addition method was used as a bench-mark proof for phosphopeptide quantification in egg white samples. We postulate that the present quantitative assay for Ps holds tremendous potential and may pave the way to disease diagnostics in the near future. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07261a
Daley, Donnele; Mani, Vishnu R; Mohan, Navyatha; Akkad, Neha; Ochi, Atsuo; Heindel, Daniel W; Lee, Ki Buom; Zambirinis, Constantinos P; Pandian, Gautam Sd Balasubramania; Savadkar, Shivraj; Torres-Hernandez, Alejandro; Nayak, Shruti; Wang, Ding; Hundeyin, Mautin; Diskin, Brian; Aykut, Berk; Werba, Gregor; Barilla, Rocky M; Rodriguez, Robert; Chang, Steven; Gardner, Lawrence; Mahal, Lara K; Ueberheide, Beatrix; Miller, George
2017-05-01
The progression of pancreatic oncogenesis requires immune-suppressive inflammation in cooperation with oncogenic mutations. However, the drivers of intratumoral immune tolerance are uncertain. Dectin 1 is an innate immune receptor crucial for anti-fungal immunity, but its role in sterile inflammation and oncogenesis has not been well defined. Furthermore, non-pathogen-derived ligands for dectin 1 have not been characterized. We found that dectin 1 is highly expressed on macrophages in pancreatic ductal adenocarcinoma (PDA). Dectin 1 ligation accelerated the progression of PDA in mice, whereas deletion of Clec7a-the gene encoding dectin 1-or blockade of dectin 1 downstream signaling was protective. We found that dectin 1 can ligate the lectin galectin 9 in mouse and human PDA, which results in tolerogenic macrophage programming and adaptive immune suppression. Upon disruption of the dectin 1-galectin 9 axis, CD4 + and CD8 + T cells, which are dispensable for PDA progression in hosts with an intact signaling axis, become reprogrammed into indispensable mediators of anti-tumor immunity. These data suggest that targeting dectin 1 signaling is an attractive strategy for developing an immunotherapy for PDA.
Kwon, Il Kyoung; Kim, Jun Pyo; Sim, Sang Jun
2010-12-15
In this study, hybrid stimulus was initially introduced to improve the sensitivity of PDA vesicle chip for detection of prostate-specific antigen-α1-antichymotrypsin (PSA-ACT) complex. The strategy of hybrid stimulus on PDA vesicle chip offers the amplification method of fluorescent signal which combines a primary response by the immune reaction of antigen-antibody and a secondary response by the mechanical pressure of pAb-conjugated magnetic beads. As the primary response result on PDA vesicle chip, the PSA-ACT complex in PBS buffer was detected at 10 ng/mL. However, this detection sensitivity was insufficient for diagnosis of prostate cancer because the normal human PSA concentration is less than 4.0 ng/mL. To solve this problem, polyclonal PSA antibody-conjugated magnetic beads were used as an amplifying agent after primary immunoresponse. As a result, the PSA-ACT complex concentrations (as low as 0.1 ng/mL) could be detected in the PBS buffer sample. Therefore, this result can be applied to various fields, such as the detection of cells, proteins, and DNA for sensitive and specific biosensing based on PDA supramolecules. Copyright © 2010 Elsevier B.V. All rights reserved.
Radiation Therapy Induces Macrophages to Suppress Immune Responses Against Pancreatic Tumors in Mice
Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Ly, Nancy Ngoc Giao; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George
2016-01-01
Background & Aims The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcome, compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of pre-invasive foci. Methods We investigated the effects of radiation in p48Cre;LSL-KrasG12D (KC) and p48Cre;LSLKrasG12D;LSL-Trp53R172H (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2–12 Gy and analyzed by flow cytometry. Results Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from invasive and pre-invasive pancreatic tumors had an immune-suppressive, M2-like phenotype, compared with control mice. Pancreata from mice exposed to radiation had fewer CD8+ T cells than controls and greater numbers of CD4+ T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. An antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Conclusions Radiation exposure causes macrophages in PDAs of mice to acquire an immune-suppressive phenotype and reduce T-cell mediated anti-tumor responses. Agents that block MCSF prevent this effect, allowing radiation to have increased efficacy in slowing tumor growth. PMID:26946344
KRAS Mutation and Epithelial-Macrophage Interplay in Pancreatic Neoplastic Transformation.
Bishehsari, Faraz; Zhang, Lijuan; Barlass, Usman; Preite, Nailliw; Turturro, Sanja; Najor, Matthew S; Shetuni, Brandon B; Zayas, Janet P; Mahdavinia, Mahboobeh; Abukhdeir, Abde M; Keshavarzian, Ali
2018-05-14
Pancreatic ductal adenocarcinoma (PDA) is characterized by epithelial mutations in KRAS and prominent tumor-associated inflammation, including macrophage infiltration. But knowledge of early interactions between neoplastic epithelium and macrophages in PDA carcinogenesis is limited. Using a pancreatic organoid model, we found that the expression of mutant KRAS in organoids increased i) ductal to acinar gene expression ratios, ii) epithelial cells proliferation, and iii) colony formation capacity in vitro, and endowed pancreatic cells with the ability to generate neoplastic tumors in vivo. KRAS mutations induced a pro-tumorigenic phenotype in macrophages. Altered macrophages decreased epithelial Pigment Epithelial Derived Factor (PEDF) expression and induced a cancerous phenotype. We validated our findings using annotated patient samples from The Cancer Genome Atlas (TCGA) as well as in our human PDA specimens. Epithelium-macrophage cross talk occurs early in pancreatic carcinogenesis where KRAS directly induces cancer-related phenotypes in epithelium, and also promotes a pro-tumorigenic phenotype in macrophages, in turn augmenting neoplastic growth. This article is protected by copyright. All rights reserved. © 2018 UICC.
Yang, Jin; Liang, Qian; Wang, Mei; Jeffries, Cynthia; Smithson, David; Tu, Ying; Boulos, Nidal; Jacob, Melissa R; Shelat, Anang A; Wu, Yunshan; Ravu, Ranga Rao; Gilbertson, Richard; Avery, Mitchell A; Khan, Ikhlas A; Walker, Larry A; Guy, R Kiplin; Li, Xing-Cong
2014-04-25
The generation of natural product libraries containing column fractions, each with only a few small molecules, using a high-throughput, automated fractionation system, has made it possible to implement an improved dereplication strategy for selection and prioritization of leads in a natural product discovery program. Analysis of databased UPLC-MS-ELSD-PDA information of three leads from a biological screen employing the ependymoma cell line EphB2-EPD generated details on the possible structures of active compounds present. The procedure allows the rapid identification of known compounds and guides the isolation of unknown compounds of interest. Three previously known flavanone-type compounds, homoeriodictyol (1), hesperetin (2), and sterubin (3), were identified in a selected fraction derived from the leaves of Eriodictyon angustifolium. The lignan compound deoxypodophyllotoxin (8) was confirmed to be an active constituent in two lead fractions derived from the bark and leaves of Thuja occidentalis. In addition, two new but inactive labdane-type diterpenoids with an uncommon triol side chain were also identified as coexisting with deoxypodophyllotoxin in a lead fraction from the bark of T. occidentalis. Both diterpenoids were isolated in acetylated form, and their structures were determined as 14S,15-diacetoxy-13R-hydroxylabd-8(17)-en-19-oic acid (9) and 14R,15-diacetoxy-13S-hydroxylabd-8(17)-en-19-oic acid (10), respectively, by spectroscopic data interpretation and X-ray crystallography. This work demonstrates that a UPLC-MS-ELSD-PDA database produced during fractionation may be used as a powerful dereplication tool to facilitate compound identification from chromatographically tractable small-molecule natural product libraries.
Li, Bo-Chao; Chang, Hao; Ren, Ke-Feng; Ji, Jian
2016-11-01
Substrate-mediated delivery of functional plasmid DNA (pDNA) has been proven to be a promising strategy to promote competitiveness of endothelial cells (ECs) over smooth muscle cells (SMCs), which is beneficial to inducing fast endothelialization of implanted vascular devices. Thus, it is of great importance to develop universal approaches with simplicity and easiness to immobilize DNA complex nanoparticles on substrates. In this study, the bioinspired polydopamine (PDA) coating was employed in immobilization of DNA complex nanoparticles, which were composed of protamine (PrS) and plasmid DNA encoding with hepatocyte growth factor (HGF-pDNA) gene. We demonstrated that the DNA complex nanoparticles can be successfully immobilized onto the PDA surface. Consequently, the HGF expression of both ECs and SMCs were significantly improved when they cultured on the DNA complex nanoparticles-immobilized substrates. Furthermore, EC proliferation was specifically promoted due to bioactivity of HGF, leading to an enhancement of EC competitiveness over SMCs. Our findings demonstrated the substrate-mediated functional gene nanoparticle delivery through PDA coating as a simple and efficient approach. It may hold great potential in the field of interventional cardiovascular implants. Copyright © 2016 Elsevier B.V. All rights reserved.
Programming Wireless Handheld Devices for Applications in Teaching Astronomy
NASA Astrophysics Data System (ADS)
Budiardja, R.; Saranathan, V.; Guidry, M.
2002-12-01
Wireless technology implemented with handheld devices has attractive features because of the potential to access large amounts of data and the prospect of on-the-fly computational analysis from a device that can be carried in a shirt pocket. We shall describe applications of such technology to the general paradigm of making digital wireless connections from the field to upload information and queries to network servers, executing (potentially complex) data analysis and/or database operations on fast network computers, and returning real-time information from this analysis to the handheld device in the field. As illustration, we shall describe several client/server programs that we have written for applications in teaching introductory astronomy. For example, one program allows static and dynamic properties of astronomical objects to be accessed in a remote observation laboratory setting using a digital cell phone or PDA. Another implements interactive quizzing over a cell phone or PDA using a 700-question introductory astronomy quiz database, thus permitting students to study for astronomy quizzes in any environment in which they have a few free minutes and a digital cell phone or wireless PDA. The presentation will include hands-on demonstrations with real devices.
2D Perovskites with Short Interlayer Distance for High-Performance Solar Cell Application.
Ma, Chunqing; Shen, Dong; Ng, Tsz-Wai; Lo, Ming-Fai; Lee, Chun-Sing
2018-05-01
2D perovskites have emerged as one of the most promising photovoltaic materials owing to their excellent stability compared with their 3D counterparts. However, in typical 2D perovskites, the highly conductive inorganic layers are isolated by large organic cations leading to quantum confinement and thus inferior electrical conductivity across layers. To address this issue, the large organic cations are replaced with small propane-1,3-diammonium (PDA) cations to reduce distance between the inorganic perovskite layers. As shown by optical characterizations, quantum confinement is no longer dominating in the PDA-based 2D perovskites. This leads to considerable enhancement of charge transport as confirmed with electrochemical impedance spectroscopy, time-resolved photoluminescence, and mobility measurements. The improved electric properties of the interlayer-engineered 2D perovskites yield a power conversion efficiency of 13.0%. Furthermore, environmental stabilities of the PDA-based 2D perovskites are improved. PDA-based 2D perovskite solar cells (PSCs) with encapsulation can retain over 90% of their efficiency upon storage for over 1000 h, and PSCs without encapsulation can maintain their initial efficiency at 70 °C for over 100 h, which exhibit promising stabilities. These results reveal excellent optoelectronic properties and intrinsic stabilities of the layered perovskites with reduced interlayer distance. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Zhe, Wang; Dong, Chaofang; Sefei, Yang; Dawei, Zhang; Kui, Xiao; Xiaogang, Li
2016-08-01
Inspired by the porous morphology of anodized Ti and the adhesive versatility of polydopamine (PDA), which can induce apatite mineralization, we fabricated a novel interface by coating a porous anodized TiO2 layer with PDA to rapidly immobilize HA on Ti-based substrates. It was found that the as-prepared PDA/anodized (HD) surface exhibited nanoscale roughness, which possessed an excellent ability to form apatite when immersed in 1.5× simulated body fluid (SBF), as observed by AFM and FE-SEM. The morphology and composition of each layer were further confirmed by XPS, XRD and FTIR. The corrosion resistance of the multilayer was investigated using potentiodynamic polarization curve and electrochemical impedance spectra (EIS) measurements in a 0.9 wt% NaCl solution, the results suggested that the HA/PDA/anodized (HDA) layer increased the corrosion resistance of pure Ti with higher corrosion potential and lower passive current, the surface wettability was also enhanced with the incorporation of HA. In vitro cellular assays showed that the HDA layer stimulated cell attachment and improved the alkaline phosphate (ALP) activity. Overall, the PDA/anodized treatment provided a viable method to quickly integrate HA, and the obtained HDA layer improved both corrosion resistance and biocompatibility of the Ti surface.
Kouo, Theodore; Huang, Lanqing; Pucsek, Alexandra B; Cao, Minwei; Solt, Sara; Armstrong, Todd; Jaffee, Elizabeth
2015-04-01
Galectin-3 is a 31-kDa lectin that modulates T-cell responses through several mechanisms, including apoptosis, T-cell receptor (TCR) cross-linking, and TCR downregulation. We found that patients with pancreatic ductal adenocarcinoma (PDA) who responded to a granulocyte-macrophage colony-stimulating factor-secreting allogeneic PDA vaccine developed neutralizing antibodies to galectin-3 after immunization. We show that galectin-3 binds activated antigen-committed CD8(+) T cells only in the tumor microenvironment. Galectin-3-deficient mice exhibit improved CD8(+) T-cell effector function and increased expression of several inflammatory genes. Galectin-3 binds to LAG-3, and LAG-3 expression is necessary for galectin-3-mediated suppression of CD8(+) T cells in vitro. Lastly, galectin-3-deficient mice have elevated levels of circulating plasmacytoid dendritic cells, which are superior to conventional dendritic cells in activating CD8(+) T cells. Thus, inhibiting galectin-3 in conjunction with CD8(+) T-cell-directed immunotherapies should enhance the tumor-specific immune response. ©2015 American Association for Cancer Research.
Magnetic capture of polydopamine-encapsulated Hela cells for the analysis of cell surface proteins.
Liu, Yiying; Yan, Guoquan; Gao, Mingxia; Zhang, Xiangmin
2018-02-10
A novel method to characterize cell surface proteins and complexes has been developed. Polydopamine (PDA)-encapsulated Hela cells were prepared for plasma membrane proteome research. Since the PDA protection, the encapsulated cells could be maintained for more than two weeks. Amino groups functionalized magnetic nanoparticles were also used for cell capture by the reaction with the PDA coatings. Plasma membrane fragments were isolated and enriched with assistance of an external magnetic field after disruption of the coated cells by ultrasonic treatment. Plasma membrane proteins (PMPs) and complexes were well preserved on the fragments and identified by shot-gun proteomic analytical strategy. 385 PMPs and 1411 non-PMPs were identified using the method. 85.2% of these PMPs were lipid-raft associated proteins. Ingenuity Pathway Analysis was employed for bio-information extraction from the identified proteins. It was found that 653 non-PMPs had interactions with 140 PMPs. Among them, epidermal growth factor receptor and its complexes, and a series of important pathways including STAT3 pathway were observed. All these results demonstrated that the new approach is of great importance in applying to the research of physiological function and mechanism of the plasma membrane proteins. This work developed a novel strategy for the proteomic analysis of cell surface proteins. According to the results, 73.3% of total identified proteins were lipid-raft associated proteins, which imply that the proposed method is of great potential in the identification of lipid-raft associated proteins. In addition, a series of protein-protein interactions and pathways related to Hela cells were pointed out. All these results demonstrated that our proposed approach is of great importance and could well be applied to the physiological function and mechanism research of plasma membrane proteins. Copyright © 2017 Elsevier B.V. All rights reserved.
Enhanced autonomic shutdown of Li-ion batteries by polydopamine coated polyethylene microspheres
Baginska, Marta; Blaiszik, Benjamin J.; Rajh, Tijana; ...
2014-07-17
Thermally triggered autonomic shutdown of a Lithium-ion (Li-ion) battery is demonstrated using polydopamine (PDA)-coated polyethylene microspheres applied onto a battery anode. The microspheres are dispersed in a buffered 10 mM dopamine salt solution and the pH is raised to initiate the polymerization and coat the microspheres. Coated microspheres are then mixed with an aqueous binder, applied onto a battery anode surface, dried, and incorporated into Li-ion coin cells. FTIR and Raman spectroscopy are used to verify the presence of the polydopamine on the surface of the microspheres. Scanning electron microscopy is used to examine microsphere surface morphology and resulting anodemore » coating quality. Charge and discharge capacity, as well as impedance, are measured for Li-ion coin cells as a function of microsphere content. Autonomous shutdown is achieved by applying 1.7 mg cm –2 of PDA-coated microspheres to the electrode. Furthermore, the PDA coating significantly reduces the mass of microspheres for effective shutdown compared to our prior work with uncoated microspheres.« less
Performance evaluation of wavelet-based face verification on a PDA recorded database
NASA Astrophysics Data System (ADS)
Sellahewa, Harin; Jassim, Sabah A.
2006-05-01
The rise of international terrorism and the rapid increase in fraud and identity theft has added urgency to the task of developing biometric-based person identification as a reliable alternative to conventional authentication methods. Human Identification based on face images is a tough challenge in comparison to identification based on fingerprints or Iris recognition. Yet, due to its unobtrusive nature, face recognition is the preferred method of identification for security related applications. The success of such systems will depend on the support of massive infrastructures. Current mobile communication devices (3G smart phones) and PDA's are equipped with a camera which can capture both still and streaming video clips and a touch sensitive display panel. Beside convenience, such devices provide an adequate secure infrastructure for sensitive & financial transactions, by protecting against fraud and repudiation while ensuring accountability. Biometric authentication systems for mobile devices would have obvious advantages in conflict scenarios when communication from beyond enemy lines is essential to save soldier and civilian life. In areas of conflict or disaster the luxury of fixed infrastructure is not available or destroyed. In this paper, we present a wavelet-based face verification scheme that have been specifically designed and implemented on a currently available PDA. We shall report on its performance on the benchmark audio-visual BANCA database and on a newly developed PDA recorded audio-visual database that take include indoor and outdoor recordings.
Zhu, Rui; Gao, Feng; Piao, Ji-Gang; Yang, Lihua
2017-07-25
How to ablate tumor without damaging skin is a challenge for photothermal therapy. We, herein, report skin-safe photothermal cancer therapy provided by the responsive release of acid-activated hemolytic polymer (aHLP) from the photothermal polydopamine (PDA) nanoparticle upon irradiation at very low dosage. Upon skin-permissible irradiation (via an 850 nm laser irradiation at the power density of 0.4 W cm -2 ), the nanoparticle aHLP-PDA generates sufficient localized-heat to bring about mild hyperthermia treatment and consequently, responsively sheds off the aHLP polymer from its PDA nanocore; this leads to selective cytotoxicity to cancer cells under the acidic conditions of the extracellular microenvironment of tumor. As a result, our aHLP-PDA nanoparticle upon irradiation at a low dosage effectively inhibits tumor growth without damaging skin, as demonstrated using animal models. Effective in mitigating the otherwise inevitable skin damage in tumor photothermal therapy, the nanosystem reported herein offers an efficient pathway towards skin-safe photothermal therapy.
Meeting Report: 2013 PDA Virus & TSE Safety Forum.
Willkommen, Hannelore; Blümel, Johannes; Brorson, Kurt; Chen, Dayue; Chen, Qi; Gröner, Albrecht; Hubbard, Brian R; Kreil, Thomas R; Ruffing, Michel; Ruiz, Sol; Scott, Dorothy; Silvester, Glenda
2014-01-01
The report provides a summary of the presentations and discussions at the Virus & TSE Safety Forum 2013 organized by the Parenteral Drug Association (PDA) and held in Berlin, Germany, from June 4 to 6, 2013. The conference was accompanied by a workshop, "Virus Spike Preparations and Virus Removal by Filtration: New Trends and Developments". The presentations and the discussion at the workshop are summarized in a separate report that will be published in this issue of the journal as well. As with previous conferences of this series, the PDA Virus & TSE Safety Forum 2013 provided again an excellent opportunity to exchange information and opinions between the industry, research organizations, and regulatory bodies. Updates on regulatory considerations related to virus and transmissible spongiform encephalopathy (TSE) safety of biopharmaceuticals were provided by agencies of the European Union (EU), the United States (US), and Singapore. The epidemiology and detection methods of new emerging pathogens like hepatitis E virus and parvovirus (PARV 4) were exemplified, and the risk of contamination of animal-derived raw materials like trypsin was considered in particular. The benefit of using new sequence-based virus detection methods was discussed. Events of bioreactor contaminations in the past drew the attention to root cause investigations and preventive actions, which were illustrated by several examples. Virus clearance data of specific unit operations were provided; the discussion focused on the mechanism of virus clearance and on the strategic concept of viral clearance integration. As in previous years, the virus safety section was followed by a TSE section that covered recent scientific findings that may influence the risk assessment of blood and cell substrates. These included the realization that interspecies transmission of TSE by blood components in sheep is greater than predicted by assays in transgenic mice. Also, the pathogenesis and possibility of productive TSE infection of cell substrates were considered, and cell-based assays that may be suitable for use in TSE clearance studies were discussed. The current report provides an overview about the outcomes of the 2013 PDA Virus & TSE Safety Forum, a unique event in this field. © PDA, Inc. 2014.
Treatment of pancreatic cancer with intravenous vitamin C: a case report
Serrano, Oscar K.; Spruce, Lisa R.; Chen, Qi; Levine, Mark
2018-01-01
Pancreatic ductal adenocarcinoma (PDA) has a dismal prognosis and is often discovered at an advanced stage with few therapeutic options. Current conventional regimens for PDA are associated with significant morbidity, decreased quality of life, and a considerable financial burden. As a result, some patients turn to integrative medicine therapies as an alternate option after a diagnosis of PDA. Intravenous pharmacologic ascorbic acid (PAA) is one such treatment. The use of PAA has been passionately debated for many years, but more recent rigorous scientific research has shown that there are significant blood concentration differences when ascorbic acid is given parenterally when compared to oral dosing. This pharmacologic difference appears to be critical for its role in oncology. Here, we report the use of PAA in a patient with poorly differentiated stage IV PDA as an exclusive chemotherapeutic regimen. The patient survived nearly 4 years after diagnosis, with PAA as his sole treatment, and he achieved objective regression of his disease. He died from sepsis and organ failure from a bowel perforation event. This case illustrates the possibility of PAA to effectively control tumor progression and serve as an adjunct to standard of care PDA chemotherapy regimens. Our patient’s experience with PAA should be taken into consideration, along with previous research in cell, animal, and clinical experiments to design future treatment trials. PMID:29438178
Wang, Dong-En; Yan, Jiahang; Jiang, Jingjing; Liu, Xiang; Tian, Chang; Xu, Juan; Yuan, Mao-Sen; Han, Xiang; Wang, Jinyi
2018-03-01
Sialic acid (SA) located at the terminal end of glycans on cell membranes has been shown to play an important yet distinctive role in various biological and pathological processes. Effective methods for the facile, sensitive and in situ analysis of SA on living cell surfaces are of great significance in terms of clinical diagnostics and therapeutics. Here, a new polydiacetylene (PDA) liposome-based sensor system bearing phenylboronic acid (PBA) and 1,8-naphthalimide derived fluorophore moieties was developed as a fluorescence turn-on sensor for the detection of free SA in aqueous solution and the in situ imaging of SA-terminated glycans on living cell surfaces. In the sensor system, three diacetylene monomers, PCDA-pBA, PCDA-Nap and PCDA-EA, were designed and synthesized to construct the composite PDA liposome sensor. The monomer PCDA-pBA modified with PBA molecules was employed as a receptor for SA recognition, while the monomer PCDA-Nap containing a 1,8-naphthalimide derivative fluorophore was used for fluorescence signaling. When the composite PDA liposomes were formed, the energy transfer between the fluorophore and the conjugated backbone could directly quench the fluorescence of the fluorophore. In the presence of additional SA or SA abundant cells, the strong binding of SA with PBA moieties disturbed the pendent side chain conformation, resulting in the fluorescence restoration of the fluorophore. The proposed methods realized the fluorescence turn-on detection of free SA in aqueous solution and the in situ imaging of SA on living MCF-7 cell surfaces. This work provides a new potential tool for simple and selective analysis of SA on living cell membranes.
Zhang, Yiyao; Isayev, Orkhan; Heilmann, Katharina; Schoensiegel, Frank; Liu, Li; Nessling, Michelle; Richter, Karsten; Labsch, Sabrina; Nwaeburu, Clifford C.; Mattern, Juergen; Gladkich, Jury; Giese, Nathalia; Werner, Jens; Schemmer, Peter; Gross, Wolfgang; Gebhard, Martha M.; Gerhauser, Clarissa; Schaefer, Michael; Herr, Ingrid
2014-01-01
The extreme aggressiveness of pancreatic ductal adenocarcinoma (PDA) has been associated with blocked gap junctional intercellular communication (GJIC) and the presence of cancer stem cells (CSCs). We examined whether disturbed GJIC is responsible for a CSC phenotype in established and primary cancer cells and patient tissue of PDA using interdisciplinary methods based in physiology, cell and molecular biology, histology and epigenetics. Flux of fluorescent dyes and gemcitabine through gap junctions (GJs) was intact in less aggressive cells but not in highly malignant cells with morphological dysfunctional GJs. Among several connexins, only Cx43 was expressed on the cell surface of less aggressive and GJIC-competent cells, whereas Cx43 surface expression was absent in highly malignant, E-cadherin-negative and GJIC-incompetent cells. The levels of total Cx43 protein and Cx43 phosphorylated at Ser368 and Ser279/282 were high in normal tissue but low to absent in malignant tissue. si-RNA-mediated inhibition of Cx43 expression in GJIC-competent cells prevented GJIC and induced colony formation and the expression of stem cell-related factors. The bioactive substance sulforaphane enhanced Cx43 and E-cadherin levels, inhibited the CSC markers c-Met and CD133, improved the functional morphology of GJs and enhanced GJIC. Sulforaphane altered the phosphorylation of several kinases and their substrates and inhibition of GSK3, JNK and PKC prevented sulforaphane-induced CX43 expression. The sulforaphane-mediated expression of Cx43 was not correlated with enhanced Cx43 RNA expression, acetylated histone binding and Cx43 promoter de-methylation, suggesting that posttranslational phosphorylation is the dominant regulatory mechanism. Together, the absence of Cx43 prevents GJIC and enhances aggressiveness, whereas sulforaphane counteracts this process, and our findings highlight dietary co-treatment as a viable treatment option for PDA. PMID:24742583
Forster, Tobias; Rausch, Vanessa; Zhang, Yiyao; Isayev, Orkhan; Heilmann, Katharina; Schoensiegel, Frank; Liu, Li; Nessling, Michelle; Richter, Karsten; Labsch, Sabrina; Nwaeburu, Clifford C; Mattern, Juergen; Gladkich, Jury; Giese, Nathalia; Werner, Jens; Schemmer, Peter; Gross, Wolfgang; Gebhard, Martha M; Gerhauser, Clarissa; Schaefer, Michael; Herr, Ingrid
2014-03-30
The extreme aggressiveness of pancreatic ductal adenocarcinoma (PDA) has been associated with blocked gap junctional intercellular communication (GJIC) and the presence of cancer stem cells (CSCs). We examined whether disturbed GJIC is responsible for a CSC phenotype in established and primary cancer cells and patient tissue of PDA using interdisciplinary methods based in physiology, cell and molecular biology, histology and epigenetics. Flux of fluorescent dyes and gemcitabine through gap junctions (GJs) was intact in less aggressive cells but not in highly malignant cells with morphological dysfunctional GJs. Among several connexins, only Cx43 was expressed on the cell surface of less aggressive and GJIC-competent cells, whereas Cx43 surface expression was absent in highly malignant, E-cadherin-negative and GJIC-incompetent cells. The levels of total Cx43 protein and Cx43 phosphorylated at Ser368 and Ser279/282 were high in normal tissue but low to absent in malignant tissue. si-RNA-mediated inhibition of Cx43 expression in GJIC-competent cells prevented GJIC and induced colony formation and the expression of stem cell-related factors. The bioactive substance sulforaphane enhanced Cx43 and E-cadherin levels, inhibited the CSC markers c-Met and CD133, improved the functional morphology of GJs and enhanced GJIC. Sulforaphane altered the phosphorylation of several kinases and their substrates and inhibition of GSK3, JNK and PKC prevented sulforaphane-induced CX43 expression. The sulforaphane-mediated expression of Cx43 was not correlated with enhanced Cx43 RNA expression, acetylated histone binding and Cx43 promoter de-methylation, suggesting that posttranslational phosphorylation is the dominant regulatory mechanism. Together, the absence of Cx43 prevents GJIC and enhances aggressiveness, whereas sulforaphane counteracts this process, and our findings highlight dietary co-treatment as a viable treatment option for PDA.
Zhu, Miao-Miao; Cui, Hong-Guang; Teng, Xiao-Dong
2015-01-01
Purpose Primary ductal adenocarcinoma (PDA) of the lacrimal gland is a rare malignant epithelial tumor, and its clinicopathological characteristics are still unclear. This study aimed to report a novel case of PDA of the lacrimal gland in the People’s Republic of China, as well as to determine its histopathological and immunohistochemical characteristics to support early diagnosis and direct further therapy. Patient and methods Clinical data (including ocular examination, computed tomography, magnetic resonance imaging, positron emission tomography, mammography, and serum tumor marker examination) and treatment of a 49-year-old woman with a left lacrimal gland mass, which was diagnosed as PDA of the lacrimal gland, were reported. Histopathological and immunohistochemical studies were performed. Eleven papers regarding this uncommon neoplasm were reviewed. Results Histopathologically, most of the tumor cells featured abundant granular eosinophilic cytoplasm, while few of them had a frothy appearance. The mass showed breast ductal carcinoma-like structural features, which most commonly demonstrated central necrosis, while less of these features showed cord-like infiltration. Immunohistochemically, the tumor cells were positive for GCDFP-15, CK 18 (++), AR (90%), Her-2 (+++), P53 (100%), and Ki-67 (with a proliferation index approximately 60%), while they were negative for ER, PR, P63, calponin, and CD 117. Conclusion This was the first Chinese case of PDA of the lacrimal gland that had been reported. We suggested that GCDFP-15, AR, and Her-2 should be tested as biomarkers for ductal adenocarcinoma of lacrimal gland to confirm diagnosis, guide therapy, and further predict prognosis. PMID:25999735
NASA Astrophysics Data System (ADS)
Nopwinyuwong, Atchareeya; Kitaoka, Takuya; Boonsupthip, Waraporn; Pechyen, Chiravoot; Suppakul, Panuwat
2014-09-01
Polydiacetylene (PDA)/silica nanocomposites were synthesized by self-assembly method using polymerizable amphiphilic diacetylene monomers, 10,12-pentacosadiynoic acid (PCDA). Addition of cationic surfactants (PDADMAC and CTAB) to PDA/SiO2 nanocomposites induced higher intermolecular force which affected their size, shape and color transition. Pure PDA, PDA/SiO2, PDA/SiO2/PDADMAC and PDA/SiO2/CTAB were investigated by particle size analysis, TEM, SEM, UV-vis spectroscopy and FT-IR. It was found that the PDA/SiO2 nanocomposites exhibited slightly larger particle sizes than those of other samples. The PDA/SiO2 nanocomposites with a core-shell structure were almost regarded as spherical-shaped particles. Cationic surfactants, especially CTAB, presumably affected the particle size and shape of PDA/SiO2 nanocomposites due to the disruption of hydrogen bonding between PDA head group and ammonium group. The colorimetric response of both PDA/SiO2/surfactant and surfactant-free PDA/SiO2 aqueous solutions directly changed in relation to time and temperature; thus they were expected to be applied as a new polymer-based time-temperature indicator (TTI).
Meeting Report: 2015 PDA Virus & TSE Safety Forum.
Willkommen, Hannelore; Blümel, Johannes; Brorson, Kurt; Chen, Dayue; Chen, Qi; Gröner, Albrecht; Kreil, Thomas R; Ruffing, Michel; Ruiz, Sol; Scott, Dorothy; Silvester, Glenda
2016-01-01
The report provides a summary of the presentations at the Virus & TSE Safety Forum 2015 organized by the Parenteral Drug Association (PDA) and held in Cascais, Portugal, from 9 to 11 June, 2015. As with previous conferences of this series, the PDA Virus & TSE Safety Forum 2015 provided an excellent forum for the exchange of information and opinions between the industry, research organizations, and regulatory bodies. Regulatory updates on virus and TSE safety aspects illustrating current topics of discussion at regulatory agencies in Europe and the United States were provided; the conference covered emerging viruses and new virus detection systems that may be used for the investigation of human pathogenic viruses as well as the virus safety of cell substrates and of raw material of ovine/caprine or human origin. Progress of development and use of next-generation sequencing methods was shown by several examples. Virus clearance data illustrating the effectiveness of inactivation or removal methods were presented and data provided giving insight into the mechanism of action of these technologies. In the transmissible spongiform encephalopathy (TSE) part of the conference, the epidemiology of variant Creutzfeldt-Jakob disease was reviewed and an overview about diagnostic tests provided; current thinking about the spread and propagation of prions was presented and the inactivation of prions by disinfection (equipment) and in production of bovine-derived reagents (heparin) shown. The current report provides an overview about the outcomes of the 2015 PDA Virus & TSE Safety Forum, a unique event in this field. © PDA, Inc. 2016.
Cellular uptake and trafficking of polydiacetylene micelles
NASA Astrophysics Data System (ADS)
Gravel, Edmond; Thézé, Benoit; Jacques, Isabelle; Anilkumar, Parambath; Gombert, Karine; Ducongé, Frédéric; Doris, Eric
2013-02-01
Polydiacetylene (PDA) micelles coated with either carboxylate-, ammonium-, or methoxy-polyethyleneglycol (PEG) chains were assembled and loaded with a fluorescent dye (DiO). Their interaction with MCF-7 human breast tumor cells was investigated by epi-fluorescence microscopy and fluorescence-activated cell sorting (FACS) to determine their internalization pathway and intracellular fate. It was found that the ionic character of the micelles influenced their internalization kinetics through a caveolae-mediated pathway and that all micelle types behaved somewhat similarly inside cells.Polydiacetylene (PDA) micelles coated with either carboxylate-, ammonium-, or methoxy-polyethyleneglycol (PEG) chains were assembled and loaded with a fluorescent dye (DiO). Their interaction with MCF-7 human breast tumor cells was investigated by epi-fluorescence microscopy and fluorescence-activated cell sorting (FACS) to determine their internalization pathway and intracellular fate. It was found that the ionic character of the micelles influenced their internalization kinetics through a caveolae-mediated pathway and that all micelle types behaved somewhat similarly inside cells. Electronic supplementary information (ESI) available: Detailed synthetic procedures and supplementary figures. See DOI: 10.1039/c2nr34149b
Matthew, Andrew G; Currie, Kristen L; Irvine, Jane; Ritvo, Paul; Santa Mina, Daniel; Jamnicky, Leah; Nam, Robert; Trachtenberg, John
2007-01-01
Background In clinical and research practice linked to prostate cancer treatment, frequent monitoring of patient health-related quality of life (HRQOL) is essential. Practical and analytic limitations of paper questionnaire data capture may be overcome with the use of self-administered personal digital assistant (PDA) data collection. The objective of this study was to assess the reliability, validity, and feasibility of using PDA in place of paper versions of the International Prostate Symptom Score (IPSS), the Patient Oriented Prostate Cancer Utility Survey (PORPUS), and the International Index of Erectile Function-5 (IIEF-5) in a prostate cancer clinic setting. Methods 152 participants were randomly assigned to one of three conditions: 1) paper followed by PDA survey; 2) PDA followed by paper survey; or 3) PDA followed by PDA survey. Evaluation included an assessment of data quality (internal consistency, test-retest reliability, response correlation, completeness of data), and feasibility (participation rates, time to completion, preference and difficultly/ease of using PDA). Results Internal consistency was similar for both PDA and paper applications. Test-retest reliability was confirmed for PDA repeated administration. Data from paper and PDA questionnaires were strongly correlated. Lower missed item rates were found in PDA administration. 82.8% of participants preferred using the PDA or had no preference. Mean difficulty/ease ratings indicated that participants found the PDA easy to use. Age did not significantly correlate with preference or difficulty. Conclusion The results confirm the adaptability of the IPSS, IIEF-5, and the PORPUS to PDA administration. Similarly, the findings of this study support the feasibility of using PDA technology for HRQOL serial data capture in the prostate cancer patient population. PMID:17617906
NASA Astrophysics Data System (ADS)
Matulla, Christoph; Namyslo, Joachim; Fuchs, Tobias; Türk, Konrad
2013-04-01
The European road sector is vulnerable to extreme weather phenomena, which can cause large socio-economic losses. Almost every year there occur several weather triggered events (like heavy precipitation, floods, landslides, high winds, snow and ice, heat or cold waves, etc.), that disrupt transportation, knock out power lines, cut off populated regions from the outside and so on. So, in order to avoid imbalances in the supply of vital goods to people as well as to prevent negative impacts on health and life of people travelling by car it is essential to know present and future threats to roads. Climate change might increase future threats to roads. CliPDaR focuses on parts of the European road network and contributes, based on the current body of knowledge, to the establishment of guidelines helping to decide which methods and scenarios to apply for the estimation of future climate change based challenges in the field of road maintenance. Based on regional scale climate change projections specific road-impact models are applied in order to support protection measures. In recent years, it has been recognised that it is essential to assess the uncertainty and reliability of given climate projections by using ensemble approaches and downscaling methods. A huge amount of scientific work has been done to evaluate these approaches with regard to reliability and usefulness for investigations on possible impacts of climate changes. CliPDaR is going to collect the existing approaches and methodologies in European countries, discuss their differences and - in close cooperation with the road owners - develops a common line on future applications of climate projection data to road impact models. As such, the project will focus on reviewing and assessing existing regional climate change projections regarding transnational highway transport needs. The final project report will include recommendations how the findings of CliPDaR may support the decision processes of European national road administrations regarding possible future climate change impacts. First project results are presented at the conference.
Tchoukouegno Ngueu, Sadrine; Tchoumtchoua, Job; Njamen, Dieudonné; Halabalaki, Maria; Laudenbach-Leschowski, Ute; Diel, Patrick
2016-01-01
Eythrina excelsa Baker (Fabaceae) is a medicinal plant used to treat various ailments including those of the female genital tract. The objective of this study is to investigate the estrogenic and cytotoxic effects of the ethanol extract of the stem bark of E. excelsa. Erythrina excelsa was evaluated in vitro using the yeast estrogen screen (YES). The extract was then tested in a 3-day uterotrophic assay on ovariectomised Wistar rats at doses of 50 and 100 mg/kg BW/d. Cytotoxic effects were assessed on breast (MCF-7) and colon (HT-29) cancer cell lines using the MTT cell viability assay. Additionally, a LC-PDA-ESI (+)-HRMS and HRMS/MS method was developed and applied for the identification of representative secondary metabolites scaffolds in the extract. In the YES, the extract stimulated the transactivation of the estrogen receptor in a dose-dependent manner with an EC50 value of 1.8 μg/mL. In rats, E. excelsa increased uterine wet weight, uterine epithelial height, and the mRNA expression of estrogen-responsive genes in the uterus and liver at 50 whereas at 100 mg/kg BW/d anti-estrogenic effects were observed. In the MTT-assay, a dose-dependent decrease of the viability of both cell lines was observed with EC50 values of 13.6 μg/mL (MCF-7) and 27.7 μg/mL (HT-29). The phytochemical analysis revealed that the extract is rich in isoflavonoids, mainly prenylated and pyran-derivatives thereof. Erythrina excelsa is rich in prenylated and pyran-substituted isoflavonoids, exhibits estrogenic/anti-estrogenic and cytotoxic effects and warrant sufficient interest for deeper investigations.
Chinese Nurses' Acceptance of PDA: A Cross-Sectional Survey Using a Technology Acceptance Model.
Wang, Yanling; Xiao, Qian; Sun, Liu; Wu, Ying
2016-01-01
This study explores Chinese nurses' acceptance of PDA, using a questionnaire based on the framework of Technology Acceptance Model (TAM). 357 nurses were involved in the study. The results reveal the scores of the nurses' acceptance of PDA were means 3.18~3.36 in four dimensions. The younger of nurses, the higher nurses' title, the longer previous usage time, the more experienced using PDA, and the more acceptance of PDA. Therefore, the hospital administrators may change strategies to enhance nurses' acceptance of PDA, and promote the wide application of PDA.
NASA Astrophysics Data System (ADS)
Wang, Ning; Zhang, Di; Deng, Xinyu; Sun, Ying; Wang, Xinghua; Ma, Pinyi; Song, Daqian
2018-02-01
Herein we report a novel polydopamine-silver nanoparticle-polydopamine-gold (PDA-AgNPs-PDA-Au) film based surface plasmon resonance (SPR) biosensor for horse IgG detection. The PDA-AgNPs-PDA-Au film sensing platform was built on Au-film via layer-by-layer self-assembly. Ag ion was reduced in situ to AgNPs in presence of PDA. The top PDA layer can prevent AgNPs from being oxidized and connect with antibody via Schiff alkali reaction directly. The morphology and thickness of the modified gold film were characterized using scanning electron microscope and Talystep. Experimental results show that the PDA-AgNPs-PDA-Au film sensing platform is stable, regenerative and sensitive for horse IgG detection. The detection limit of horse IgG obtained with the present biosensor is 0.625 μg mL- 1, which is 2-fold and 4-fold lower than that obtained with biosensor based on PDA modified Au film and conventional biosensor based on MPA, respectively. Furthermore, when challenged to real serum samples, our sensor exhibited excellent specificity to horse IgG, suggesting its potential for industrial application.
NASA Astrophysics Data System (ADS)
Dasraf, D.; Djer, M. M.; Advani, N.
2017-08-01
Persistent ductus arteriosus is one of the most frequent congenital heart diseases found in infants, mainly in preterms. Echocardiography is the gold standard for the diagnosis of hemodynamically significant patent ductus arteriosus (hs-PDA) in preterm neonates. A few studies have suggested that the use of a simple blood assay to detect N-terminal pro-brain natriuretic peptide (NT-proBNP) may be useful in determining the diagnosis and management of hs-PDA. No such studies have been conducted in Indonesia, although the assay kit and characteristics of the patient (gestational age and chronological age) influence the accuracy of NT-proBNP levels in determining hs-PDA. The aim of this study was to determine the association between the NT-proBNP level and the prevalence of hs-PDA in an Indonesian patient population. A cross-sectional study was conducted at Dr. Cipto Mangunkusumo Hospital. PDA was determined using echocardiography in 49 preterm neonates (gestational age <37 weeks and birthweight <2000 g). Subsequently, these patients were divided into three groups: non-PDA, non-hsPDA, and hs-PDA. The blood NT-proBNP level was then determined in the non-hsPDA and hs-PDA groups, and between-group differences were compared. Among the 49 neonates, 33 patients had PDA, and 16 of these had hs-PDA. The results revealed a significant association between the NT-proBNP level and hs-PDA (p < 0.001).
Shafi, Nabil A; Singh, Gagan D; Smith, Thomas W; Rogers, Jason H
2018-05-01
To describe a novel balloon sizing technique used during adult transcatheter patent ductus arteriosus (PDA) closure. In addition, to determine the clinical and procedural outcomes in six patients who underwent PDA balloon sizing with subsequent deployment of a PDA occluder device. Transcatheter PDA closure in adults has excellent safety and procedural outcomes. However, PDA sizing in adults can be challenging due to variable defect size, high flow state, or anatomical complexity. We describe a series of six cases where the balloon- pull through technique was successfully performed for PDA sizing prior to transcatheter closure. Consecutive adult patients undergoing adult PDA closure at our institution were studied retrospectively. A partially inflated sizing balloon was pulled through the defect from the aorta into the pulmonary artery and the balloon waist diameter was measured. Procedural success and clinical outcomes were obtained. Six adult patients underwent successful balloon pull-through technique for PDA sizing during transcatheter PDA closure, since conventional angiography often gave suboptimal opacification of the defect. All PDAs were treated with closure devices based on balloon PDA sizing with complete closure and no complications. In three patients that underwent preprocedure computed tomography, the balloon size matched the CT derived measurements. The balloon pull-through technique for PDA sizing is a safe and accurate sizing modality in adults undergoing transcatheter PDA closure. © 2017 Wiley Periodicals, Inc.
Terek, Demet; Yalaz, Mehmet; Ulger, Zulal; Koroglu, Ozge Altun; Kultursay, Nilgun
2014-01-01
Background: Although, patent ductus arteriosus (PDA) is associated with significant morbidity due to hemodynamic instability in preterm infants, the effect of ductus closure on mortality and morbidity is a controversial issue. The aim is to evaluate the efficacy of oral and intravenous (IV) ibuprofen treatment on ductal closure and effects on mortality and bronchoplumonary dysplasia. Materials and Methods: The medical records of 292 premature infants treated at Ege University Neonatal Intensive Care Unit were retrospectively evaluated. Patients were classified into 3 groups as; No PDA, hemodynamically insignificant PDA (hiPDA) and hemodynamically significant PDA (hsPDA) according to the presence and hemodynamical significance of PDA by echocardiography. hsPDA group was treated with IV or oral ibuprofen. Results: Patent ductus arteriosus was diagnosed by routine echocardiography in 145 patients, of whom 78 (53.7%) had hsPDA. All 65 infants with hiPDA had spontaneous PDA closure. Echocardiographic measurements were similar to those patients treated with oral or IV ibuprofen, as in the response rate to treatment without serious adverse effects. The presence of respiratory distress syndrome, surfactant therapy, late sepsis, bronchopulmonary dysplasia (BPD) and mortality rates were significantly higher in patients with hsPDA. However, with stepwise logistic regression; 5th min Apgar score (odds ratio [OR], 1.321, 95% confidence interval [CI], 1.063-1.641, P = 0.012) and gestational age (OR, 1.422, 95% CI, 1.212-1.662, P < 0.001) were the only significant variables associated with mortality. Gestational age (OR, 0.680, 95% CI, 0.531-0.871, P = 0.002) was the only significant variable associated with BPD shown with logistic regression. Conclusion: Ibuprofen treatment is effective for hsPDA closure with minimal side effects. HiPDA can close spontaneously; therefore treatment decision should be individualized. However, medical treatment of PDA does not reduce mortality and BPD. PMID:25657754
Terek, Demet; Yalaz, Mehmet; Ulger, Zulal; Koroglu, Ozge Altun; Kultursay, Nilgun
2014-11-01
Although, patent ductus arteriosus (PDA) is associated with significant morbidity due to hemodynamic instability in preterm infants, the effect of ductus closure on mortality and morbidity is a controversial issue. The aim is to evaluate the efficacy of oral and intravenous (IV) ibuprofen treatment on ductal closure and effects on mortality and bronchoplumonary dysplasia. The medical records of 292 premature infants treated at Ege University Neonatal Intensive Care Unit were retrospectively evaluated. Patients were classified into 3 groups as; No PDA, hemodynamically insignificant PDA (hiPDA) and hemodynamically significant PDA (hsPDA) according to the presence and hemodynamical significance of PDA by echocardiography. hsPDA group was treated with IV or oral ibuprofen. Patent ductus arteriosus was diagnosed by routine echocardiography in 145 patients, of whom 78 (53.7%) had hsPDA. All 65 infants with hiPDA had spontaneous PDA closure. Echocardiographic measurements were similar to those patients treated with oral or IV ibuprofen, as in the response rate to treatment without serious adverse effects. The presence of respiratory distress syndrome, surfactant therapy, late sepsis, bronchopulmonary dysplasia (BPD) and mortality rates were significantly higher in patients with hsPDA. However, with stepwise logistic regression; 5(th) min Apgar score (odds ratio [OR], 1.321, 95% confidence interval [CI], 1.063-1.641, P = 0.012) and gestational age (OR, 1.422, 95% CI, 1.212-1.662, P < 0.001) were the only significant variables associated with mortality. Gestational age (OR, 0.680, 95% CI, 0.531-0.871, P = 0.002) was the only significant variable associated with BPD shown with logistic regression. Ibuprofen treatment is effective for hsPDA closure with minimal side effects. HiPDA can close spontaneously; therefore treatment decision should be individualized. However, medical treatment of PDA does not reduce mortality and BPD.
Wang, Yi; Wei, Guoqing; Zhang, Xiaobin; Huang, Xuehui; Zhao, Jingya; Guo, Xing; Zhou, Shaobing
2018-03-01
Mitochondrial-targeting therapy is an emerging strategy for enhanced cancer treatment. In the present study, a multistage targeting strategy using doxorubicin-loaded magnetic composite nanoparticles is developed for enhanced efficacy of photothermal and chemical therapy. The nanoparticles with a core-shell-SS-shell architecture are composed of a core of Fe 3 O 4 colloidal nanocrystal clusters, an inner shell of polydopamine (PDA) functionalized with triphenylphosphonium (TPP), and an outer shell of methoxy poly(ethylene glycol) linked to the PDA by disulfide bonds. The magnetic core can increase the accumulation of nanoparticles at the tumor site for the first stage of tumor tissue targeting. After the nanoparticles enter the tumor cells, the second stage of mitochondrial targeting is realized as the mPEG shell is detached from the nanoparticles by redox responsiveness to expose the TPP. Using near-infrared light irradiation at the tumor site, a photothermal effect is generated from the PDA photosensitizer, leading to a dramatic decrease in mitochondrial membrane potential. Simultaneously, the loaded doxorubicin can rapidly enter the mitochondria and subsequently damage the mitochondrial DNA, resulting in cell apoptosis. Thus, the synergism of photothermal therapy and chemotherapy targeting the mitochondria significantly enhances the cancer treatment. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Hussmann, Stephan; Lau, Wing Y.; Chu, Terry; Grothof, Markus
2003-07-01
Traditionally, the measuring or monitoring system of manufacturing industries uses sensors, computers and screens for their quality control (Q.C.). The acquired information is fed back to the control room by wires, which - for obvious reason - are not suitable in many environments. This paper describes a method to solve this problem by employing the new Bluetooth technology to set up a complete new system, where a total wireless solution is made feasible. This new Q.C. system allows several line scan cameras to be connected at once to a graphical user interface (GUI) that can monitor the production process. There are many Bluetooth devices available on the market such as cell-phones, headsets, printers, PDA etc. However, the detailed application is a novel implementation in the industrial Q.C. area. This paper will contain more details about the Bluetooth standard and why it is used (nework topologies, host controller interface, data rates, etc.), the Bluetooth implemetation in the microcontroller of the line scan camera, and the GUI and its features.
Cook, Natalie; Bapiro, Tashinga E.; Lolkema, Martijn P.; Jodrell, Duncan I.; Tuveson, David A.
2016-01-01
nab-paclitaxel, an albumin-stabilized paclitaxel formulation, demonstrates clinical activity when administered in combination with gemcitabine in patients with metastatic pancreatic ductal adenocarcinoma (PDA). The limited availability of patient tissue and exquisite sensitivity of xenografts to chemotherapeutics have limited our ability to address the mechanistic basis of this treatment regimen. Here, we used a mouse model of PDA to show that the co-administration of nab-paclitaxel and gemcitabine uniquely demonstrates evidence of tumor regression. Combination treatment increases intratumoral gemcitabine levels due to a marked decrease in the primary gemcitabine metabolizing enzyme, cytidine deaminase (Cda). Correspondingly, paclitaxel reduced Cda protein levels in cultured cells through reactive oxygen species-mediated degradation, resulting in the increased stabilization of gemcitabine. Our findings support the concept that suboptimal intratumoral concentrations of gemcitabine represent a crucial mechanism of therapeutic resistance in PDA and highlight the advantages of genetically engineered mouse models in preclinical therapeutic trials. PMID:22585996
Hamamura, Kensuke; Yanagida, Mitsuaki; Ishikawa, Hitoshi; Banzai, Michio; Yoshitake, Hiroshi; Nonaka, Daisuke; Tanaka, Kenji; Sakuraba, Mayumi; Miyakuni, Yasuka; Takamori, Kenji; Nojima, Michio; Yoshida, Koyo; Fujiwara, Hiroshi; Takeda, Satoru; Araki, Yoshihiko
2018-03-01
Purpose We previously attempted to develop quantitative enzyme-linked immunosorbent assay (ELISA) systems for the PDA039/044/071 peptides, potential serum disease biomarkers (DBMs) of pregnancy-induced hypertension (PIH), primarily identified by a peptidomic approach (BLOTCHIP®-mass spectrometry (MS)). However, our methodology did not extend to PDA071 (cysteinyl α2-HS-glycoprotein 341-367 ), due to difficulty to produce a specific antibody against the peptide. The aim of the present study was to establish an alternative PDA071 quantitation system using liquid chromatography-multiple reaction monitoring (LC-MRM)/MS, to explore the potential utility of PDA071 as a DBM for PIH. Methods We tested heat/acid denaturation methods in efforts to purify serum PDA071 and developed an LC-MRM/MS method allowing for specific quantitation thereof. We measured serum PDA071 concentrations, and these results were validated including by three-dimensional (3D) plotting against PDA039 (kininogen-1 439-456 )/044 (kininogen-1 438-456 ) concentrations, followed by discriminant analysis. Results PDA071 was successfully extracted from serum using a heat denaturation method. Optimum conditions for quantitation via LC-MRM/MS were developed; the assayed serum PDA071 correlated well with the BLOTCHIP® assay values. Although the PDA071 alone did not significantly differ between patients and controls, 3D plotting of PDA039/044/071 peptide concentrations and construction of a Jackknife classification matrix were satisfactory in terms of PIH diagnostic precision. Conclusions Combination analysis using both PDA071 and PDA039/044 concentrations allowed PIH diagnostic accuracy to be attained, and our method will be valuable in future pathophysiological studies of hypertensive disorders of pregnancy.
Zulqarnain, Arif; Younas, Muhammad; Waqar, Tariq; Beg, Ahsan; Asma, Touseef; Baig, Mirza Ahmad Raza
2016-01-01
Comparison of effectiveness and cost of transcatheter occlusion of patent ductus arteriosus (PDA) with surgical ligation of PDA. This retrospective comparative study was conducted in the pediatric cardiology department of Ch. Pervaiz Elahi Institute of Cardiology Multan, Pakistan. Data of 250 patients who underwent patent ductus arteriosus (PDA) closure either surgical or trans-catheter closure using SHSMA Occluder having weight >5 kg from April 2012 to October 2015 were included in this study. SPSS version 20 was used for data analysis. Quantitative variables were compared using independent sample t-test. Chi-square test and fishers exact was used for qualitative variables. P-value <0.05 was considered statistically significant. There were one hundred and twenty (120) patients who underwent transcatheter occlusion of PDA using SHSMA occluder (PDA Device Group) and one hundred and thirty (130) patients who underwent surgical ligation of PDA (Surgical Group). Incidence of residual shunting was two (1.5%) in surgical group and 0 (0.0%) in PDA Device group for one month follow up period. There were 4 (3.1%) major complications in surgical group. The rate of blood transfusions were high in surgical group (p-value 0.04). Hospital stay time was significantly less in PDA Device group (P-value <0.001). Total procedural cost was 110695+1054 Pakistani rupees in PDA Device group and 92414+3512 in surgical group (p-value <0.001). The cost of PDA device closure was 16.52% higher than the surgical ligation of PDA. There was no operative mortality. The transcatheter closure of PDA is an effective and less invasive method as compared to the surgical ligation. There is a lower rate of complications and the cost is not much high as compared to surgical PDA ligation.
Clauson, Kevin A; Polen, Hyla H; Marsh, Wallace A
2007-12-01
To evaluate personal digital assistant (PDA) drug information databases used to support clinical decision-making, and to compare the performance of PDA databases with their online versions. Prospective evaluation with descriptive analysis. Five drug information databases available for PDAs and online were evaluated according to their scope (inclusion of correct answers), completeness (on a 3-point scale), and ease of use; 158 question-answer pairs across 15 weighted categories of drug information essential to health care professionals were used to evaluate these databases. An overall composite score integrating these three measures was then calculated. Scores for the PDA databases and for each PDA-online pair were compared. Among the PDA databases, composite rankings, from highest to lowest, were as follows: Lexi-Drugs, Clinical Pharmacology OnHand, Epocrates Rx Pro, mobileMicromedex (now called Thomson Clinical Xpert), and Epocrates Rx free version. When we compared database pairs, online databases that had greater scope than their PDA counterparts were Clinical Pharmacology (137 vs 100 answers, p<0.001), Micromedex (132 vs 96 answers, p<0.001), Lexi-Comp Online (131 vs 119 answers, p<0.001), and Epocrates Online Premium (103 vs 98 answers, p=0.001). Only Micromedex online was more complete than its PDA version (p=0.008). Regarding ease of use, the Lexi-Drugs PDA database was superior to Lexi-Comp Online (p<0.001); however, Epocrates Online Premium, Epocrates Online Free, and Micromedex online were easier to use than their PDA counterparts (p<0.001). In terms of composite scores, only the online versions of Clinical Pharmacology and Micromedex demonstrated superiority over their PDA versions (p>0.01). Online and PDA drug information databases assist practitioners in improving their clinical decision-making. Lexi-Drugs performed significantly better than all of the other PDA databases evaluated. No PDA database demonstrated superiority to its online counterpart; however, the online versions of Clinical Pharmacology and Micromedex were superior to their PDA versions in answering questions.
Glucose-6-phosphate dehydrogenase deficiency and the sickle cell gene in Makkah, Saudi Arabia.
el-Hazmi, M A; Warsy, A S; Bahakim, H H; al-Swailem, A
1994-02-01
This study was conducted on 689 Saudi males and females living in the Makkah area in the western province of Saudi Arabia. The frequency of severe glucose-6-phosphate dehydrogenase (G-6-PD) deficiency in the male and female populations was 0.055 and 0.042 respectively. The normal G-6-PD was G-6-PD-B+ and the G-6-PD phenotypes identified included G-6-PD-A+, G-6-PD-A-, G-6-PD-Mediterranean, and G-6-PD-Mediterranean-like at gene frequencies of 0.0288, 0.0026, 0.05497, and 0.1969 in the male population and 0.026, 0.0146, 0.0407, and 0.02606 in the female population. The main variants producing severe and mild G-6-PD deficiency were G-6-PD-Mediterranean and G-6-PD-Mediterranean-like, respectively. The sickle cell gene was identified at a frequency of 0.029 and no interaction between sickle cell and G-6-PD deficiency genes was encountered.
The secret origins and surprising fates of pancreas tumors
Bailey, Jennifer M.; DelGiorno, Kathleen E.; Crawford, Howard C.
2014-01-01
Pancreatic ductal adenocarcinoma (PDA) is especially deadly due to its recalcitrance to current therapies. One of the unique qualities of PDA that may contribute to this resistance is a striking plasticity of differentiation states starting at tumor formation and continuing throughout tumor progression, including metastasis. Here, we explore the earliest steps of tumor formation and neoplastic progression and how this results in a fascinating cellular heterogeneity that is probably critical for tumor survival and progression. We hypothesize that reinforcing differentiation pathways run awry or targeting morphologically and molecularly distinct tumor stem-like cells may hold promise for future treatments of this deadly disease. PMID:24583923
NASA Astrophysics Data System (ADS)
Zhang, Zhe; Zhang, Jing; Zhang, Bailin; Tang, Jilin
2012-12-01
Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs.Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32092d
Late medical therapy of patent ductus arteriosus using intravenous paracetamol.
EL-Khuffash, Afif; James, Adam T; Cleary, Aoife; Semberova, Jana; Franklin, Orla; Miletin, Jan
2015-05-01
To investigate the effect of late treatment with intravenous paracetamol on patent ductus arteriosus (PDA) closure prior to possible PDA ligation. A retrospective review of infants with a haemodynamically significant PDA, considered for PDA ligation and treated with intravenous paracetamol prior to possible ligation. Thirty six infants with a median gestation of 26.1 weeks received paracetamol at a median age of 27 days. Paracetamol was associated with immediate closure in nine (25%) infants. There was no response to paracetamol treatment in four (11%) infants who subsequently underwent a PDA ligation. In 23 (64%) infants, the PDA constricted and all but one of this group demonstrated complete PDA closure prior to discharge. There may be a role for intravenous paracetamol in late closure of infants with a significant PDA to avoid ligation. The use of paracetamol for late treatment of PDA should be systematically evaluated. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
The impact of a personal digital assistant (PDA) case log in a medical student clerkship.
Ho, Kendall; Lauscher, Helen Novak; Broudo, Marc; Jarvis-Selinger, Sandra; Fraser, Joan; Hewes, Deborah; Scott, Ian
2009-10-01
Medical education literature emphasizes that reflection and self-audit are pivotal steps in learning and that personal digital assistants (PDAs) have potential as decision support tools. The purpose was to examine the efficacy of PDA-based resources and patient-encounter logging systems among 3rd-year medical clerks during pediatrics rotations. Students in rotations were assigned to control (using paper-based logs and references) or intervention groups (using PDA-based logs and resources). Students completed pre- and postrotation Paediatrics Competency Surveys, participated in focus groups, and were compared on year-end examination grades. Use of PDA logs far outweighed that of paper logs (1,020 PDA logs and 87 paper logs). PDA logs were ranked significantly higher in enhancing learning and reflection than paper logs (t = 2.52, p < .01). PDA logs also facilitated specific learning experiences. PDA-based patient-encounter logs appear to be effective case documentation and reflection tools. The difference in number of logs between control and intervention groups demonstrates the utility of the PDA for "point-of-care" patient logging.
Thompson, Elizabeth J; Greenberg, Rachel G; Kumar, Karan; Laughon, Matthew; Smith, P Brian; Clark, Reese H; Crowell, Andromeda; Shaw, Layla; Harrison, Louis; Scales, Gabrielle; Bell, Nicole; Hornik, Christoph P
2018-05-08
To evaluate the association between furosemide exposure and patent ductus arteriosus (PDA) in a large, contemporary cohort of hospitalized infants with very low birth weight (VLBW). Using the Pediatrix Medical Group Clinical Data Warehouse, we identified all inborn infants of VLBW <37 weeks of gestation discharged from the neonatal intensive care unit after the first postnatal week from 2011 to 2015. We defined PDA as any medical (ibuprofen or indomethacin) or surgical PDA therapy. We collected data up to the day of PDA treatment or postnatal day 18 for infants not diagnosed with PDA. We performed multivariable logistic regression to evaluate the association between PDA and exposure to furosemide. We included 43 576 infants from 337 neonatal intensive care units, of whom 6675 (15%) underwent PDA treatment. Infants with PDA were more premature and more often exposed to mechanical ventilation and inotropes. Furosemide was prescribed to 4055 (9%) infants. On multivariable regression, exposure to furosemide was associated with decreased odds of PDA treatment (OR 0.72; 95% CI 0.65-0.79). Increasing percentage of days with furosemide exposure was not associated with PDA treatment (OR 1.01; 95% CI 0.97-1.06). Furosemide exposure was not associated with increased odds of PDA treatment in hospitalized infants of VLBW. Further studies are needed to characterize the efficacy and safety of furosemide in premature infants. Copyright © 2018 Elsevier Inc. All rights reserved.
Pulmonary artery dissection in eight dogs with patent ductus arteriosus.
Scansen, Brian A; Simpson, Elaine M; López-Alvarez, Jordi; Thomas, William P; Bright, Janice M; Eason, Bryan D; Rush, John E; Dukes-McEwan, Joanna; Green, Henry W; Cunningham, Suzanne M; Visser, Lance C; Kent, Agnieszka M; Schober, Karsten E
2015-06-01
To describe a series of dogs with pulmonary artery dissection and patent ductus arteriosus (PDA). Eight dogs. Retrospective case series. Pulmonary artery dissection was diagnosed in 8 dogs, 3 were Weimaraners. Four dogs presented in left-sided congestive heart failure, 4 presented for murmur evaluation and without clinical signs, and 1 presented in right-sided congestive heart failure. In 7 dogs the dissection was first documented concurrent with a diagnosis of uncorrected PDA. In the other dog, with pulmonary valve stenosis and PDA, the dissection was observed on autopsy examination 17 months after balloon pulmonary valvuloplasty and ductal closure. Median age at presentation for the 7 dogs with antemortem diagnosis of pulmonary artery dissection was 3.5 years (range, 1.5-4 years). Three dogs had the PDA surgically ligated, 2 dogs did not undergo PDA closure, 1 dog failed transcatheter occlusion of the PDA with subsequent surgical ligation, 1 dog underwent successful transcatheter device occlusion of the PDA, and 1 dog had the PDA closed by transcatheter coil delivery 17 months prior to the diagnosis of pulmonary artery dissection. The 2 dogs that did not have the PDA closed died 1 and 3 years after diagnosis due to heart failure. Pulmonary artery dissection is a potential complication of PDA in dogs, the Weimaraner breed may be at increased risk, presentation is often in mature dogs, and closure of the PDA can be performed and appears to improve outcome. Copyright © 2014 Elsevier B.V. All rights reserved.
Boghossian, Nansi S; Do, Barbara T; Bell, Edward F; Dagle, John M; Brumbaugh, Jane E; Stoll, Barbara J; Vohr, Betty R; Das, Abhik; Shankaran, Seetha; Sanchez, Pablo J; Wyckoff, Myra H; Bethany Ball, M
2017-10-01
Optimal management of the patent ductus arteriosus (PDA) in preterm infants remains controversial. Therefore, studies identifying infants who are most likely to benefit from PDA treatment are needed. We sought to examine if significant intrauterine growth restriction, defined by birth weight z-score, reduces the efficacy of PDA closure with indomethacin or ibuprofen and thereby increases the need for surgical closure of PDA after pharmacologic treatment. We studied infants 23-28weeks' gestation born 2006-2013 at NICHD Neonatal Research Network centers. We examined the responses to PDA treatment with indomethacin and/or ibuprofen and whether the PDA was subsequently closed surgically. Logistic regression generated adjusted odds ratios (ORs) for the associations between the z-score groups (<-2, -2 to -0.5, and >-0.5) and PDA surgery following pharmacologic treatment. 5606 infants were diagnosed with PDA; 3587 (64.0%) received indomethacin or ibuprofen or both, and 909 (25.3%) underwent PDA surgery. Mothers of infants with PDA non-closure were less likely to have hypertension (19% vs. 28%). Infants with non-closure were more likely to be female (53% vs. 49%), have lower gestational age and birth weight and to develop sepsis (42% vs. 31%). Compared to infants with z-score>-0.5, PDA surgery was increased among infants with z-score -2 to -0.5 (OR=1.23; 95% CI 1.02-1.47) but not among infants with z-score<-2. Infants with birth weight z-score -2 to -0.5 are more likely than normally grown infants to require PDA surgery following pharmacologic treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Kim, Joon Sik
2012-01-01
Background and Objectives Patent ductus arteriosus (PDA) is a significant cause of morbidity and mortality in preterm infants. Measurement of plasma B-type natriuretic peptide (BNP) has been reported to be a useful bedside screening tool for the presence of hemodynamically significant PDA (hsPDA) in neonates. This study was conducted to investigate the usefulness of a BNP assay as a biochemical marker for the diagnosis of hsPDA and predictive biomarker of the response to indomethacin in preterm infants. Subjects and Methods Preterm infants born at <37 weeks' gestational age were prospectively enrolled within 24 hours of birth. Plasma BNP levels were measured on days 1, 4, and 7. Significant PDA was diagnosed by large ductal flow with left to right shunt on color Doppler echocardiography, along with clinical features of PDA. Following that, hsPDA was treated with indomethacin. Results A total of 28 preterm infants were prospectively enrolled in this study. Seven infants with PDA had higher on day 4 plasma BNP values (median 654.68 pg/mL; range 428.29-1280.00) compared to the control group (median 124.52 pg/mL; range 37.21-290.49). The area under the receiver operator characteristic curve for the detection of hsPDA was high: 0.998 (95% confidence interval: 0.995-1.002). The cutoff of BNP concentration for the diagnosis of hsPDA was determined to be 412 pg/mL (sensitivity: 100%; specificity: 95%). Conclusion B-type natriuretic peptide can be a useful biomarker for the screening and diagnosis of PDA in preterm infants. Serial BNP measurements are valuable for assessing the clinical course and indomethacin responsiveness of PDA. PMID:22493614
Yang, Chuan-Zhong; Lee, Jiun
2008-05-01
The incidence of patent ductus arteriosus (PDA) is high in extremely low birth weight (ELBW) infants. Indomethacin has been widely used in the prophylaxis and treatment of hemodynamically significant PDA. This retrospective study was undertaken to identify factors such as birth weight, gestational age, gender, fetal growth retardation, ductal size, timing of the first dose of indomethacin and side effects of indomethacin, which may affect the successful closure of the PDA with indomethacin in ELBW infants. A cohort of 139 ELBW infants who had received indomethacin treatment for PDA during a consecutive period of more than three years (September 2000 to December 2003) was retrospectively analyzed. Administration of indomethacin was associated with closure of PDA in 108 (77.7%) of 139 ELBW infants, and only 19.4% of infants required surgical ligation of the ductus eventually. There was no significant relationship between closure of PDA with gestational age, gender, fetal growth retardation, and ductal size. A higher birth weight and early use of indomethacin after birth could significantly increase the closure rate of PDA (P<0.05). Side effects of indomethacin such as transient oliguria and hyponatremia during indomethacin therapy did not affect PDA closure. Indomethacin is effective for the treatment of PDA in ELBW infants. A higher rate of ductal closure is related to the increase of birth weight. PDA closure with indomethacin is age-related, and early administration of indomethacin could increase PDA closure and reduce the incidence of hyponatremia. There is no significant difference in major morbidities such as bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP) after early treatment. Early screening for hemodynamically significant PDA in ELBW infants and early treatment with indomethacin are recommended.
Investigating the electronic properties of Al2O3/Cu(In,Ga)Se2 interface
NASA Astrophysics Data System (ADS)
Kotipalli, R.; Vermang, B.; Joel, J.; Rajkumar, R.; Edoff, M.; Flandre, D.
2015-10-01
Atomic layer deposited (ALD) Al2O3 films on Cu(In,Ga)Se2 (CIGS) surfaces have been demonstrated to exhibit excellent surface passivation properties, which is advantageous in reducing recombination losses at the rear metal contact of CIGS thin-film solar cells. Here, we report, for the first time, experimentally extracted electronic parameters, i.e. fixed charge density (Qf) and interface-trap charge density (Dit), for as-deposited (AD) and post-deposition annealed (PDA) ALD Al2O3 films on CIGS surfaces using capacitance-voltage (C-V) and conductance-frequency (G-f) measurements. These results indicate that the AD films exhibit positive fixed charges Qf (approximately 1012 cm-2), whereas the PDA films exhibit a very high density of negative fixed charges Qf (approximately 1013 cm-2). The extracted Dit values, which reflect the extent of chemical passivation, were found to be in a similar range of order (approximately 1012 cm-2 eV-1) for both AD and PDA samples. The high density of negative Qf in the bulk of the PDA Al2O3 film exerts a strong Coulomb repulsive force on the underlying CIGS minority carriers (ns), preventing them to recombine at the CIGS/Al2O3 interface. Using experimentally extracted Qf and Dit values, SCAPS simulation results showed that the surface concentration of minority carriers (ns) in the PDA films was approximately eight-orders of magnitude lower than in the AD films. The electrical characterization and estimations presented in this letter construct a comprehensive picture of the interfacial physics involved at the Al2O3/CIGS interface.
Zulqarnain, Arif; Younas, Muhammad; Waqar, Tariq; Beg, Ahsan; Asma, Touseef; Baig, Mirza Ahmad Raza
2016-01-01
Objectives: Comparison of effectiveness and cost of transcatheter occlusion of patent ductus arteriosus (PDA) with surgical ligation of PDA. Methods: This retrospective comparative study was conducted in the pediatric cardiology department of Ch. Pervaiz Elahi Institute of Cardiology Multan, Pakistan. Data of 250 patients who underwent patent ductus arteriosus (PDA) closure either surgical or trans-catheter closure using SHSMA Occluder having weight >5 kg from April 2012 to October 2015 were included in this study. SPSS version 20 was used for data analysis. Quantitative variables were compared using independent sample t-test. Chi-square test and fishers exact was used for qualitative variables. P-value <0.05 was considered statistically significant. Results: There were one hundred and twenty (120) patients who underwent transcatheter occlusion of PDA using SHSMA occluder (PDA Device Group) and one hundred and thirty (130) patients who underwent surgical ligation of PDA (Surgical Group). Incidence of residual shunting was two (1.5%) in surgical group and 0 (0.0%) in PDA Device group for one month follow up period. There were 4 (3.1%) major complications in surgical group. The rate of blood transfusions were high in surgical group (p-value 0.04). Hospital stay time was significantly less in PDA Device group (P-value <0.001). Total procedural cost was 110695+1054 Pakistani rupees in PDA Device group and 92414+3512 in surgical group (p-value <0.001). The cost of PDA device closure was 16.52% higher than the surgical ligation of PDA. There was no operative mortality. Conclusion: The transcatheter closure of PDA is an effective and less invasive method as compared to the surgical ligation. There is a lower rate of complications and the cost is not much high as compared to surgical PDA ligation. PMID:27648051
Punchaichira, Toyanji Joseph; Dey, Sanjay Kumar; Mukhopadhyay, Anirban; Kundu, Suman; Thelma, B K
2017-07-01
Dopamine-β-hydroxylase (DBH, EC 1.14.17.1), an oxido-reductase that catalyses the conversion of dopamine to norepinephrine, is largely expressed in sympathetic neurons and adrenal medulla. Several regulatory and structural variants in DBH associated with various neuropsychiatric, cardiovascular diseases and a few that may determine enzyme activity have also been identified. Due to paucity of studies on functional characterization of DBH variants, its structure-function relationship is poorly understood. The purpose of the study was to characterize five non-synonymous (ns) variants that were prioritized either based on previous association studies or Sorting Tolerant From Intolerant (SIFT) algorithm. The DBH ORF with wild type (WT) and site-directed mutagenized variants were transfected into HEK293 cells to generate transient and stable lines expressing these variant enzymes. Activity was determined by UPLC-PDA and corresponding quantity by MRM HR on a TripleTOF 5600 MS respectively of spent media from stable cell lines. Homospecific activity computed for the WT and variant proteins showed a marginal decrease in A318S, W544S and R549C variants. In transient cell lines, differential secretion was observed in the case of L317P, W544S and R549C. Secretory defect in L317P was confirmed by localization in ER. R549C exhibited both decreased homospecific activity and differential secretion. Of note, all the variants were seen to be destabilizing based on in silico folding analysis and molecular dynamics (MD) simulation, lending support to our experimental observations. These novel genotype-phenotype correlations in this gene of considerable pharmacological relevance have implications for dopamine-related disorders.
Pancreatic Cancer Metabolism: Breaking It Down to Build It Back Up.
Perera, Rushika M; Bardeesy, Nabeel
2015-12-01
How do cancer cells escape tightly controlled regulatory circuits that link their proliferation to extracellular nutrient cues? An emerging theme in cancer biology is the hijacking of normal stress response mechanisms to enable growth even when nutrients are limiting. Pancreatic ductal adenocarcinoma (PDA) is the quintessential aggressive malignancy that thrives in nutrient-poor, hypoxic environments. PDAs overcome these limitations through appropriation of unorthodox strategies for fuel source acquisition and utilization. In addition, the interplay between evolving PDA and whole-body metabolism contributes to disease pathogenesis. Deciphering how these pathways function and integrate with one another can reveal novel angles of therapeutic attack. Alterations in tumor cell and systemic metabolism are central to the biology of pancreatic cancer. Further investigation of these processes will provide important insights into how these tumors develop and grow, and suggest new approaches for its detection, prevention, and treatment. ©2015 American Association for Cancer Research.
Liao, Gaoyong; Gao, Bing; Gao, Yingnv; Yang, Xuegan; Cheng, Xiaodong; Ou, Yu
2016-01-01
Pancreatic adenocarcinoma (PDA) is one of the most lethal human malignancies, and unresponsive to current chemotherapies. Here we investigate the therapeutic potential of phycocyanin as an anti-PDA agent in vivo and in vitro. Phycocyanin, a natural product purified from Spirulina, effectively inhibits the pancreatic cancer cell proliferation in vitro and xenograft tumor growth in vivo. Phycocyanin induces G2/M cell cycle arrest, apoptotic and autophagic cell death in PANC-1 cells. Inhibition of autophagy by targeting Beclin 1 using siRNA significantly suppresses cell growth inhibition and death induced by phycocyanin, whereas inhibition of both autophagy and apoptosis rescues phycocyanin-mediated cell death. Mechanistically, cell death induced by phycocyanin is the result of cross-talk among the MAPK, Akt/mTOR/p70S6K and NF-κB pathways. Phycocyanin is able to induce apoptosis of PANC-1 cell by activating p38 and JNK signaling pathways while inhibiting Erk pathway. On the other hand, phycocyanin promotes autophagic cell death by inhibiting PI3/Akt/mTOR signaling pathways. Furthermore, phycocyanin promotes the activation and nuclear translocation of NF-κB, which plays an important role in balancing phycocyanin-mediated apoptosis and autosis. In conclusion, our studies demonstrate that phycocyanin exerts anti-pancreatic cancer activity by inducing apoptotic and autophagic cell death, thereby identifying phycocyanin as a promising anti-pancreatic cancer agent. PMID:27694919
Polydiacetylene chromism towards toxic chemical detection via molecular size-dependent selectivity
NASA Astrophysics Data System (ADS)
Seo, Donghwan
Polydiacetylene (PDA) is a pi-conjugated polymer that has unique optical properties. PDA changes color from blue to red when subjected to various stimuli such as mechanical stress, heat, photoirradiation, pH change, and binding of specific ligands. The steric effect induced by those stimuli on PDA headgroup has been investigated to understand the mechanism of PDA chromism and to apply those optical properties to the development of various sensors. In this work, pH chromism of PDA was examined in terms of the effects of the molecular size and acidity of acid analytes with the consideration of the molecular design aspect of diacetylene lipids. The pH level is an important parameter, since a low pH will produce a charge on the amine headgroup of PDA, but this does not necessarily result in PDA chromatic transition from 'blue phase' to 'red phase.' The molecular size of the counter anion was identified as another determinant condition to ensure the perturbation of the ene-yne conjugated backbone of PDA, which produces the chromatic transition. In the molecular design of the sensory diacetylene lipids, the alkyl spacer length between the amine as a receptor and the amide linker was found to strongly affect the degree of PDA chromatic transition. The longer alkyl spacer showed the less chromatic transition. The length of alkyl spacer seems to promote the flexibility of the molecule diminishing the extent of the transfer of the steric effect at PDA headgroup to the conjugated backbone. Finally, PDA chromism dependent on the molecular size of acid analytes was applied to develop the colorimetric detection of diethyl phosphate (DEP), a degraded nerve agent simulant. PDA liposome sensors successfully showed selective chromatic transition with fluorescent emission upon binding of DEP compared to other acid analytes. The molecular size and acidity of acid analytes, and alkyl spacer length have proven to be correlated with PDA chromism. These new findings provide further understanding of the mechanism of PDA chromism and the molecular design principle of diacetylene in fundamental studies and in the development of various applications.
NASA Astrophysics Data System (ADS)
Ruan, Mengnan; Yang, Dan; Guo, Wenli; Zhang, Liqun; Li, Shuxin; Shang, Yuwei; Wu, Yibo; Zhang, Min; Wang, Hao
2018-05-01
Surface functionalization of Al2O3 nano-particles by mussel-inspired poly(dopamine) (PDA) was developed to improve the dielectric properties, mechanical properties, and thermal conductivity properties of nitrile rubber (NBR) matrix. As strong adhesion of PDA to Al2O3 nano-particles and hydrogen bonds formed by the catechol groups of PDA and the polar acrylonitrile groups of NBR, the dispersion of Al2O3-PDA/NBR composites was improved and the interfacial force between Al2O3-PDA and NBR matrix was enhanced. Thus, the Al2O3-PDA/NBR composites exhibited higher dielectric constant, better mechanical properties, and larger thermal conductivity comparing with Al2O3/NBR composites at the same filler content. The largest thermal conductivity of Al2O3-PDA/NBR composite filled with 30 phr Al2O3-PDA was 0.21 W/m K, which was 122% times of pure NBR. In addition, the Al2O3-PDA/NBR composite filled with 30 phr Al2O3-PDA displayed a high tensile strength about 2.61 MPa, which was about 255% of pure NBR. This procedure is eco-friendly and easy handling, which provides a promising route to polymer composites in application of thermal conductivity field.
Effects of post-deposition annealing on sputtered SiO2/4H-SiC metal-oxide-semiconductor
NASA Astrophysics Data System (ADS)
Lee, Suhyeong; Kim, Young Seok; Kang, Hong Jeon; Kim, Hyunwoo; Ha, Min-Woo; Kim, Hyeong Joon
2018-01-01
Reactive sputtering followed by N2, NH3, O2, and NO post-deposition annealing (PDA) of SiO2 on 4H-SiC was investigated in this study. The results of ellipsometry, an etching test, and X-ray photoemission spectroscopy showed that N2 and NH3 PDA nitrified the SiO2. Devices using N2 and NH3 PDA exhibited a high gate leakage current and low breakdown field due to oxygen vacancies and incomplete oxynitride. SiO2/4H-SiC MOS capacitors were also fabricated and their electrical characteristics measured. The average breakdown fields of the devices using N2, NH3, O2, and NO PDA were 0.12, 0.17, 4.71 and 2.63 MV/cm, respectively. The shifts in the flat-band voltage after O2 and NO PDA were 0.95 and -2.56 V, respectively, compared with the theoretical value. The extracted effective oxide charge was -4.11 × 1011 cm-2 for O2 PDA and 1.11 × 1012 cm-2 for NO PDA. NO PDA for 2 h at 1200 °C shifted the capacitance-voltage curve in the negative direction. The oxygen containing PDA showed better electrical properties than non-oxygen PDA. The sputtering method described can be applied to 4H-SiC MOS fabrication.
Ning, Nanying; Ma, Qin; Liu, Suting; Tian, Ming; Zhang, Liqun; Nishi, Toshio
2015-05-27
In this study, we obtained dielectric elastomer composites with controllable dielectric and actuated properties by using a biomimetic method. We used dopamine (DA) to simultaneously coat the graphene oxide (GO) and partially reduce GO by self-polymerization of DA on GO. The poly(dopamine) (PDA) coated GO (GO-PDA) was assembled around rubber latex particles by hydrogen bonding interaction between carboxyl groups of carboxylated nitrile rubber (XNBR) and imino groups or phenolic hydroxyl groups of GO-PDA during latex compounding, forming a segregated GO-PDA network at a low percolation threshold. The results showed that the introduction of PDA on GO prevented the restack of GO in the matrix. The dielectric and actuated properties of the composites depend on the thickness of PDA shell. The dielectric loss and the elastic modulus decrease, and the breakdown strength increases with increasing the thickness of PDA shell. The maximum actuated strain increases from 1.7% for GO/XNBR composite to 4.4% for GO-PDA/XNBR composites with the PDA thickness of about 5.4 nm. The actuated strain at a low electric field (2 kV/mm) obviously increases from 0.2% for pure XNBR to 2.3% for GO-PDA/XNBR composite with the PDA thickness of 1.1 nm, much higher than that of other DEs reported in previous studies. Thus, we successfully obtained dielectric composites with low dielectric loss and improved breakdown strength and actuated strain at a low electric field, facilitating the wide application of dielectric elastomers.
Tan, Yueming; Deng, Wenfang; Li, Yunyong; Huang, Zhao; Meng, Yue; Xie, Qingji; Ma, Ming; Yao, Shouzhuo
2010-04-22
We report here on the facile preparation of polymer-enzyme-multiwalled carbon nanotubes (MWCNTs) cast films accompanying in situ laccase (Lac)-catalyzed polymerization for electrochemical biosensing and biofuel cell applications. Lac-catalyzed polymerization of dopamine (DA) as a new substrate was examined in detail by UV-vis spectroscopy, cyclic voltammetry, quartz crystal microbalance, and scanning electron microscopy. Casting the aqueous mixture of DA, Lac and MWCNTs on a glassy carbon electrode (GCE) yielded a robust polydopamine (PDA)-Lac-MWCNTs/GCE that can sense hydroquinone with 643 microA mM(-1) cm(-2) sensitivity and 20-nM detection limit (S/N = 3). The DA substrate yielded the best biosensing performance, as compared with aniline, o-phenylenediamine, or o-aminophenol as the substrate for similar Lac-catalyzed polymerization. Casting the aqueous mixture of DA, glucose oxidase (GOx), Lac, and MWCNTs on a Pt electrode yielded a robust PDA-GOx-Lac-MWCNTs/Pt electrode that exhibits glucose-detection sensitivity of 68.6 microA mM(-1) cm(-2). In addition, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) diammonium salt (ABTS) was also coimmobilized to yield a PDA-Lac-MWCNTs-ABTS/GCE that can effectively catalyze the reduction of O(2), and it was successfully used as the biocathode of a membraneless glucose/O(2) biofuel cell (BFC) in pH 5.0 Britton-Robinson buffer. The proposed biomacromolecule-immobilization platform based on enzyme-catalyzed polymerization may be useful for preparing many other multifunctional polymeric bionanocomposites for wide applications.
NASA Astrophysics Data System (ADS)
Budiardja, R. D.; Lingerfelt, E. J.; Guidry, M. W.
2003-05-01
Wireless technology implemented with handheld devices has attractive features because of the potential to access large amounts of data and the prospect of on-the-fly computational analysis from a device that can be carried in a shirt pocket. We shall describe applications of such technology to the general paradigm of making digital wireless connections from the field to upload information and queries to network servers, executing (potentially complex) programs and controlling data analysis and/or database operations on fast network computers, and returning real-time information from this analysis to the handheld device in the field. As illustration, we shall describe several client/server programs that we have written for applications in teaching introductory astronomy. For example, one program allows static and dynamic properties of astronomical objects to be accessed in a remote observation laboratory setting using a digital cell phone or PDA. Another implements interactive quizzing over a cell phone or PDA using a 700-question introductory astronomy quiz database, thus permitting students to study for astronomy quizzes in any environment in which they have a few free minutes and a digital cell phone or wireless PDA. Another allows one to control and monitor a computation done on a Beowulf cluster by changing the parameters of the computation remotely and retrieving the result when the computation is done. The presentation will include hands-on demonstrations with real devices. *Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
Validation of the pulse decomposition analysis algorithm using central arterial blood pressure
2014-01-01
Background There is a significant need for continuous noninvasive blood pressure (cNIBP) monitoring, especially for anesthetized surgery and ICU recovery. cNIBP systems could lower costs and expand the use of continuous blood pressure monitoring, lowering risk and improving outcomes. The test system examined here is the CareTaker® and a pulse contour analysis algorithm, Pulse Decomposition Analysis (PDA). PDA’s premise is that the peripheral arterial pressure pulse is a superposition of five individual component pressure pulses that are due to the left ventricular ejection and reflections and re-reflections from only two reflection sites within the central arteries. The hypothesis examined here is that the model’s principal parameters P2P1 and T13 can be correlated with, respectively, systolic and pulse pressures. Methods Central arterial blood pressures of patients (38 m/25 f, mean age: 62.7 y, SD: 11.5 y, mean height: 172.3 cm, SD: 9.7 cm, mean weight: 86.8 kg, SD: 20.1 kg) undergoing cardiac catheterization were monitored using central line catheters while the PDA parameters were extracted from the arterial pulse signal obtained non-invasively using CareTaker system. Results Qualitative validation of the model was achieved with the direct observation of the five component pressure pulses in the central arteries using central line catheters. Statistically significant correlations between P2P1 and systole and T13 and pulse pressure were established (systole: R square: 0.92 (p < 0.0001), diastole: R square: 0.78 (p < 0.0001). Bland-Altman comparisons between blood pressures obtained through the conversion of PDA parameters to blood pressures of non-invasively obtained pulse signatures with catheter-obtained blood pressures fell within the trend guidelines of the Association for the Advancement of Medical Instrumentation SP-10 standard (standard deviation: 8 mmHg(systole: 5.87 mmHg, diastole: 5.69 mmHg)). Conclusions The results indicate that arterial blood pressure can be accurately measured and tracked noninvasively and continuously using the CareTaker system and the PDA algorithm. The results further support the physical model that all of the features of the pressure pulse envelope, whether in the central arteries or in the arterial periphery, can be explained by the interaction of the left ventricular ejection pressure pulse with two centrally located reflection sites. PMID:25005686
Recent Advances in the Treatment of Preterm Newborn Infants with Patent Ductus Arteriosus.
Sallmon, Hannes; Koehne, Petra; Hansmann, Georg
2016-03-01
A patent ductus arteriosus (PDA) is associated with several adverse clinical conditions. Several strategies for PDA treatment exist, although data regarding the benefits of PDA treatment on outcomes are sparse. Moreover, the optimal treatment strategy for preterm neonates with PDA remains subject to debate. It is still unknown whether and when PDA treatment should be initiated and which approach (conservative, pharmacologic, or surgical) is best for individual patients (tailored therapies). This article reviews the current strategies for PDA treatment with a special focus on recent developments such as oral ibuprofen, high-dose regimens, and the use of paracetamol (oral, intravenous). Copyright © 2016 Elsevier Inc. All rights reserved.
HWANG, HUI-JEONG; YOON, KYUNG LIM; SOHN, IL SUK
2016-01-01
The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans. PMID:26998021
Hwang, Hui-Jeong; Yoon, Kyung Lim; Sohn, Il Suk
2016-03-01
The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans.
NASA Astrophysics Data System (ADS)
Palanisamy, Selvakumar; Thirumalraj, Balamurugan; Chen, Shen-Ming; Wang, Yi-Ting; Velusamy, Vijayalakshmi; Ramaraj, Sayee Kannan
2016-09-01
We report a novel and sensitive amperometric sensor for chlorpromazine (CPZ) based on reduced graphene oxide (RGO) and polydopamine (PDA) composite modified glassy carbon electrode. The RGO@PDA composite was prepared by electrochemical reduction of graphene oxide (GO) with PDA. The RGO@PDA composite modified electrode shows an excellent electro-oxidation behavior to CPZ when compared with other modified electrodes such as GO, RGO and GO@PDA. Amperometric i-t method was used for the determination of CPZ. Amperometry result shows that the RGO@PDA composite detects CPZ in a linear range from 0.03 to 967.6 μM. The sensor exhibits a low detection limit of 0.0018 μM with the analytical sensitivity of 3.63 ± 0.3 μAμM-1 cm-2. The RGO@PDA composite shows its high selectivity towards CPZ in the presence of potentially interfering drugs such as metronidazole, phenobarbital, chlorpheniramine maleate, pyridoxine and riboflavin. In addition, the fabricated RGO@PDA modified electrode showed an appropriate recovery towards CPZ in the pharmaceutical tablets.
Osma, Jorge; García-Palacios, Azucena; Botella, Cristina; Barrada, Juan Ramón
2014-05-01
No studies have been found that compared the psychopathology features, including personality disorders, of Panic Disorder (PD) and Panic Disorder with Agoraphobia (PDA), and a nonclinical sample with anxiety vulnerability. The total sample included 152 participants, 52 in the PD/PDA, 45 in the high anxiety sensitivity (AS) sample, and 55 in the nonclinical sample. The participants in PD/PDA sample were evaluated with the structured interview ADIS-IV. The Brief Symptom Inventory and the MCMI-III were used in all three samples. Statistically significant differences were found between the PD/PDA and the nonclinical sample in all MCMI-III scales except for antisocial and compulsive. No significant differences were found between PD/PDA and the sample with high scores in AS. Phobic Anxiety and Paranoid Ideation were the only scales where there were significant differences between the PD/PDA sample and the high AS sample. Our findings showed that people who scored high on AS, despite not having a diagnosis of PD/PDA, were similar in regard to psychopathology features and personality to individuals with PD/PDA.
To Close or Not to Close: The Very Small Patent Ductus Arteriosus
Fortescue, Elizabeth B.; Lock, James E.; Galvin, Teresa; McElhinney, Doff B.
2014-01-01
Patent ductus arteriosus (PDA) accounts for approximately 10% of all congenital heart diseases, with an incidence of at least 2–4 per 1000 term births. Closure of the large, hemodynamically significant PDA is established as the standard of care, and can be performed safely and effectively using either surgical or transcatheter methods. The appropriate management of the very small, hemodynamically insignificant PDA is less clear. Routine closure of such defects has been advocated to eliminate or reduce the risk of infective endocarditis (IE). However, the risk of IE in patients with a small PDA appears to be extremely low, and IE is treatable. Although closure of the small PDA is generally safe and technically successful, it is unknown whether this treatment truly improves the risk : benefit balance compared with observation. In this article, we review the published literature on the natural history and treatment outcomes in individuals with a PDA, the epidemiology and outcomes of IE, particularly in association with PDA, and the rationale and evidence for closure of the very small PDA. PMID:20653702
Liao, Qi-wei; Zhang, Wei-hua; Guang, Xue-feng; Lu, Yi-bing
2013-03-01
To explore the risk factors of patent ductus arteriosus (PDA) patients with thrombocytopenia after PDA interventional occlusion. Thrombocytopenia occurred in 14 out of 350 patients underwent PDA occlusion. Age, gender, body weight, PDA size, occluder size, mean pulmonary arterial pressure, the dose of heparin, the manufacturer of occluder, residual shunt after operation were analyzed. The recovery time of different grades of thrombocytopenia was observed. Multivariate logistic regression showed that the PDA size (OR = 2.238, P < 0.05), the dose of heparin (OR = 3.247, P < 0.05), residual shunt after operation (OR = 1.912, P < 0.01) were the independent risk factors of thrombocytopenia after PDA occlusion. The recovery time of mild thrombocytopenia was (7 ± 2) days without treatment. The recovery time of moderate thrombocytopenia was (12 ± 4) days with glucocorticoids treatment. The recovery time of severe thrombocytopenia was (21 ± 7) days with platelet transfusion. The occluder size, dose of heparin, residual shunt are the independent risk factors of thrombocytopenia after PDA interventional occlusion. Recover time of thrombocytopenia after PDA interventional occlusion is closely related to the severity of thrombocytopenia.
Hagadorn, James I; Brownell, Elizabeth A; Trzaski, Jennifer M; Johnson, Kendall R; Lainwala, Shabnam; Campbell, Brendan T; Herbst, Katherine W
2016-12-01
We examined recent trends and interhospital variation in use of indomethacin, ibuprofen, and surgical ligation for patent ductus arteriosus (PDA) in very-low-birth-weight (VLBW) infants. Included in this retrospective study of the Pediatric Hospital Information System database were 13,853 VLBW infants from 19 US children's hospitals, admitted at age < 3 d between 1 January 2005 and 31 December 2014. PDA management and in-hospital outcomes were examined for trends and variation. PDA was diagnosed in 5,719 (42%) VLBW infants. Cyclooxygenase inhibitors and/or ligation were used in 74% of infants with PDA overall, however studied hospitals varied greatly in PDA management. Odds of any cyclooxygenase inhibitor or surgical treatment for PDA decreased 11% per year during the study period. This was temporally associated with improved survival but also with increasing bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, and acute renal failure in unadjusted analyses. There was no detectable correlation between hospital-specific changes in PDA management and hospital-specific changes in outcomes of preterm birth during the study period. Use of cyclooxygenase inhibitors and ligation for PDA in VLBW infants decreased over a 10-y period at the studied hospitals. Further evidence is needed to assess the impact of this change in PDA management.
McCord, Gary; Pendleton, Brian F; Schrop, Susan Labuda; Weiss, Lisa; Stockton, LuAnne; Hamrich, Lynn M
2009-01-01
The effects of the use of technological devices on dimensions that affect the physician-patient relationship need to be well understood. Determine patients' perceptions of physicians' personal digital assistant (PDA) use, comparing the results across 8 physician-patient dimensions important to clinical interactions. Patients completed anonymous surveys about their perceptions of physician PDA use. Data were collected during 2006 and 2007 at 12 family medicine practices. Survey items included physician sex, patient demographics, if physicians explained why they were using the PDA, and Likert ratings on 8 dimensions of how a PDA can influence physician-patient interactions (surprise, confidence, feelings, comfort, communication, relationship, intelligence, and satisfaction). The survey response rate was 78%. Physicians explained to their patients what they were doing with the PDA 64% of the time. Logistic regression analyses determined that patients of male physicians, patients attending private practices and underserved sites, patients with Medicaid insurance, and patients who observed their physician using a PDA during both the index visit and at least one prior visit were more likely to receive an explanation of PDA use. Most importantly, physician-patient communication was rated significantly more positive if an explanation of PDA use was offered. Patients rate interactions with their physicians more positively when physicians explain their PDA use.
Transcatheter closure of patent ductus arteriosus: past, present and future.
Baruteau, Alban-Elouen; Hascoët, Sébastien; Baruteau, Julien; Boudjemline, Younes; Lambert, Virginie; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme; Pass, Robert
2014-02-01
This review aims to describe the past history, present techniques and future directions in transcatheter treatment of patent ductus arteriosus (PDA). Transcatheter PDA closure is the standard of care in most cases and PDA closure is indicated in any patient with signs of left ventricular volume overload due to a ductus. In cases of left-to-right PDA with severe pulmonary arterial hypertension, closure may be performed under specific conditions. The management of clinically silent or very tiny PDAs remains highly controversial. Techniques have evolved and the transcatheter approach to PDA closure is now feasible and safe with current devices. Coils and the Amplatzer Duct Occluder are used most frequently for PDA closure worldwide, with a high occlusion rate and few complications. Transcatheter PDA closure in preterm or low-bodyweight infants remains a highly challenging procedure and further device and catheter design development is indicated before transcatheter closure is the treatment of choice in this delicate patient population. The evolution of transcatheter PDA closure from just 40 years ago with 18F sheaths to device delivery via a 3F sheath is remarkable and it is anticipated that further improvements will result in better safety and efficacy of transcatheter PDA closure techniques. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Performance and Mechanism of Uranium Adsorption from Seawater to Poly(dopamine)-Inspired Sorbents.
Wu, Fengcheng; Pu, Ning; Ye, Gang; Sun, Taoxiang; Wang, Zhe; Song, Yang; Wang, Wenqing; Huo, Xiaomei; Lu, Yuexiang; Chen, Jing
2017-04-18
Developing facile and robust technologies for effective enrichment of uranium from seawater is of great significance for resource sustainability and environmental safety. By exploiting mussel-inspired polydopamine (PDA) chemistry, diverse types of PDA-functionalized sorbents including magnetic nanoparticle (MNP), ordered mesoporous carbon (OMC), and glass fiber carpet (GFC) were synthesized. The PDA functional layers with abundant catechol and amine/imine groups provided an excellent platform for binding to uranium. Due to the distinctive structure of PDA, the sorbents exhibited multistage kinetics which was simultaneously controlled by chemisorption and intralayer diffusion. Applying the diverse PDA-modified sorbents for enrichment of low concentration (parts per billion) uranium in laboratory-prepared solutions and unpurified seawater was fully evaluated under different scenarios: that is, by batch adsorption for MNP and OMC and by selective filtration for GFC. Moreover, high-resolution X-ray photoelectron spectroscopic and extended X-ray absorption fine structure studies were performed for probing the underlying coordination mechanism between PDA and U(VI). The catechol hydroxyls of PDA were identified as the main bidentate ligands to coordinate U(VI) at the equatorial plane. This study assessed the potential of versatile PDA chemistry for development of efficient uranium sorbents and provided new insights into the interaction mechanism between PDA and uranium.
Hamabe, L; Kim, S; Yoshiyuki, R; Fukayama, T; Nakata, T M; Fukushima, R; Tanaka, R
2015-01-01
Closure of PDA can be associated with echocardiographic changes including deterioration of LV systolic function. Although PDA is commonly encountered in dogs, few comprehensive reports of echocardiographic changes in dogs with PDA closure are available. To evaluate the short-term echocardiographic changes observed after PDA closure in dogs using strain analysis. Seventeen client-owned dogs with left-to-right PDA. Echocardiographic evaluations, including standard echocardiography and two-dimensional tissue tracking (2DTT), were performed before and within 3 days of PDA closure. Preclosure examination showed LV and left atrial dilatation indicating volume overload as a result of PDA. Closure of PDA resulted in significant reduction of LVIDd (<.0001) and LA/Ao (0.01) without change in LVIDs, suggestive of decreased preload. Postclosure LV systolic dysfunction was observed with significant decreased in FS (<.0001) and strain values (P = .0039 for radial strains, P = .0005 for circumferential strains). Additionally, significant LV dyssynchrony (P = .0162) was observed after closure of PDA. Closure of PDA resulted in decreased preload as a result of alleviation of LV volume overload, which in turn caused transient deterioration of LV systolic function. Additionally, this study demonstrated that strain analysis is load dependent. Therefore, care should be taken when interpreting strain measurements as an indicator of LV systolic function. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.
El-Khuffash, A; Barry, D; Walsh, K; Davis, P G; Molloy, E J
2008-11-01
A patent ductus arteriosus (PDA) in preterm infants is associated with increased risk of intraventricular haemorrhage (IVH) and death. Cardiac troponin T (cTnT) and N-terminal-pro-B type natriuretic peptide (NTpBNP) are markers of cardiac function and can predict poor outcome in adults. To determine whether echocardiography and cTnT/NTpBNP levels at 48 h predict death before discharge or severe IVH in preterm infants with a PDA. Infants born <32 weeks' gestation or <1500 g underwent echocardiographic and cTnT/NTpBNP measurements at 12 and 48 h of life. Infants were divided according to their status at discharge: a closed PDA at 48 h, infants with a PDA at 48 h and IVH III/IV and/or death, and infants with a PDA at 48 h without IVH III/IV or death. Eighty infants with a median gestation of 28 weeks (IQR 26.1-29.5) and birth weight 1.06 kg (0.8-1.21) were included. At 48 h, infants with a PDA and IVH III/IV and/or death had significantly higher median cTnT/NTpBNP levels compared to infants with a PDA without IVH III/IV and/or death and those with spontaneous PDA closure (NTpBNP 9282, 5121 and 740 pmol/l, respectively, p = 0.008, and cTnT 0.66, 0.25 and 0.13 microg/l, respectively, p = 0.027). There were no differences in echocardiographic parameters of PDA size, left atrial to aortic ratio (LA:Ao), left and right ventricular outputs between the PDA groups. NTpBNP and cTnT in conjunction with echocardiography may provide a basis for trials of targeted medical treatment in infants with a PDA.
Chiang, Pei-Jung; Hsu, Jen-Fu; Tsai, Ming-Horng; Lien, Reyin; Chiang, Ming-Chou; Huang, Hsuan-Rong; Chiang, Chiao-Ching; Liang, Hwey-Fang; Chu, Shih-Ming
2012-10-01
Late-onset sepsis (LOS) in neonates with patent ductus arteriosus (PDA) may predispose them to more complicated hospital courses. The objective of this study was to determine the incidence, the distribution of pathogens, and the clinical features of LOS in neonates with PDA and analyze their outcomes. The medical records were reviewed retrospectively of infants with PDA and LOS who were hospitalized in NICUs of Chang Gung Children's Hospital between January 2003 and December 2009. The clinical features of these infants were compared with a group of gestational age and birth body weight-matched neonates with LOS during the same period. During this period, 224 neonates were found to have at least one event of blood-culture proven LOS and 79 (35.3%) were documented to have PDA. Although most LOS episodes (85/104, 81.7%) in neonates with PDA occurred after closure of PDA, neonates with PDA had a significantly higher rate of bronchopulmonary dysplasia (81.0% vs. 61.0%, p = 0.002) and a relatively higher rate of recurrent sepsis (25.3% vs. 15.2%, p = 0.079) than those without PDA. Longer durations of ventilator support and hospital stay were also noted in neonates with PDA as compared to those without (p = 0.001 and 0.005, respectively). In neonates with LOS, the presence of PDA, even though it is aggressively treated with indomethacin or surgical intervention, may still contribute to the complexity of hospitalization. Close monitoring and aggressive treatments are warranted in these neonates with PDA. Copyright © 2012. Published by Elsevier B.V.
Chorioamnionitis and Patent Ductus Arteriosus: A Systematic Review and Meta-Analysis
Park, Hye Won; Choi, Yong-Sung; Kim, Kyo Sun; Kim, Soo-Nyung
2015-01-01
Background Chorioamnionitis has recently been reported as a risk factor for various neonatal diseases, including cerebral palsy, bronchopulmonary dysplasia, and necrotizing enterocolitis, but its effect on patent ductus arteriosus (PDA) is unclear. We performed a systematic review and meta-analysis to evaluate the effect of chorioamnionitis on PDA. Methods We searched PubMed, EMBASE, Cochrane Library, and KoreaMed databases using the terms: “intrauterine infection” or “maternal infection” or “antenatal infection” or “chorioamnionitis” or “placenta inflammation” or “placenta pathology” or “neonatal outcome” or “neonatal morbidity” or “PDA or patent ductus arteriosus” or “ductus arteriosus,” and “prematurity” or “very low birth weight infant.” Studies were included if they were randomized controlled trials, case–control studies, or cohort studies that included information relating to chorioamnionitis and PDA. Results Among 1,571 studies, a total of 23 studies (17,708 cases) were included in the meta-analysis to analyze the relationship between chorioamnionitis and PDA, except one study that only included PDA requiring surgical ligation. The association between chorioamnionitis and PDA was statistically significant (odds ratio [OR] 1.43; 95% confidence interval [CI] 1.19, 1.72; P < 0.0001). In subgroup analysis, clinical chorioamnionitis was not associated with PDA (OR 1.28; 95% CI 1.00, 1.64, 1.790; P = 0.05), whereas histologic chorioamnionitis (OR 1.54; 95% CI 1.10, 2.15; P = 0.01) and chorioamnionitis diagnosed from both clinical and histologic findings (OR 1.75; 95% CI 1.07, 2.86; P = 0.03) showed significant associations with PDA. Chorioamnionitis did not increase the risk of PDA requiring surgical ligation (OR 1.23; 95% CI 0.69, 2.17; P = 0.48), and antenatal steroid use reduced the risk of PDA (OR 0.62; 95% CI 0.42, 0.90; P = 0.01) after chorioamnionitis. Conclusions The results from this meta-analysis support an association between maternal chorioamnionitis and PDA in offspring. PMID:26375582
Prolonged persistent patent ductus arteriosus: potential perdurable anomalies in premature infants.
Saldeño, Y P; Favareto, V; Mirpuri, J
2012-12-01
Patent ductus arteriosus (PDA) is a common condition among preterm infants. Controversy exists regarding the risk-benefit ratio of early closure of PDAs by either medical or surgical treatments. On the other hand, potential morbidities associated with no or delayed closure has not been well studied. The objective of the study was to determine if there is an association of prolonged persistent PDA (PP-PDA) with various morbidities in infants ≤28 weeks or 1250 g. This matched case-control analysis includes preterm infants with a diagnosis of PDA over a period of 28 months in a single level III center in the USA. The predictive variable was the presence of a PP-PDA (PDA>3 weeks). Cases were infants with PP-PDA and controls were those with PDA but not PP-PDA (two controls for each case). Outcome variables included days on mechanical ventilation and with oxygen treatment, length of hospital stay, bronchopulmonary dysplasia (BPD), retinopathy of prematurity stage III-V (ROP) necrotizing enterocolitis grade II or more (NEC), delayed growth, direct hyperbilirubinemia >4 mg dl(-1) and osteopenia of prematurity. Data was obtained from database collected prospectively and from the review of clinical records when necessary. Statistics included ANOVA, Kaplan-Meier curves and χ (2). Significance was set at P<0.05. PP-PDA was associated with a significant increase in the number of days of mechanical ventilation, oxygen treatment and length of hospital stay, and in the rates of BPD (60% vs 4.5%), NEC (29% vs 5%), ROP (43% vs 5%), direct hyperbilirubinemia (41% vs 3%), osteopenia (44% vs 6%), parenteral nutrition for >40 days (70% vs 21%), tracheostomy during the hospitalization (15% vs 0%) and delayed growth (70% vs 21%), were also significantly higher in babies with PP-PDA. A prolonged exposure to PDA does not seem to be inconsequential for some infants and is associated with an increase prevalence of severe morbidities with potential long lasting effects.
Treatment of severe pulmonary hypertension in the setting of the large patent ductus arteriosus.
Niu, Mary C; Mallory, George B; Justino, Henri; Ruiz, Fadel E; Petit, Christopher J
2013-05-01
Treatment of the large patent ductus arteriosus (PDA) in the setting of pulmonary hypertension (PH) is challenging. Left patent, the large PDA can result in irreversible pulmonary vascular disease. Occlusion, however, may lead to right ventricular failure for certain patients with severe PH. Our center has adopted a staged management strategy using medical management, noninvasive imaging, and invasive cardiac catheterization to treat PH in the presence of a large PDA. This approach determines the safety of ductal closure but also leverages medical therapy to create an opportunity for safe PDA occlusion. We reviewed our experience with this approach. Patients with both severe PH and PDAs were studied. PH treatment history and hemodynamic data obtained during catheterizations were reviewed. Repeat catheterizations, echocardiograms, and clinical status at latest follow-up were also reviewed. Seven patients had both PH and large, unrestrictive PDAs. At baseline, all patients had near-systemic right ventricular pressures. Nine catheterizations were performed. Two patients underwent 2 catheterizations each due to poor initial response to balloon test occlusion. Six of 7 patients exhibited subsystemic pulmonary pressures during test occlusion and underwent successful PDA occlusion. One patient did not undergo PDA occlusion. In follow-up, 2 additional catheterizations were performed after successful PDA occlusion for subsequent hemodynamic assessment. At the latest follow-up, the 6 patients who underwent PDA occlusion are well, with continued improvement in PH. Five patients remain on PH treatment. A staged approach to PDA closure for patients with severe PH is an effective treatment paradigm. Aggressive treatment of PH creates a window of opportunity for PDA occlusion, echocardiography assists in identifying the timing for closure, and balloon test occlusion during cardiac catheterization is critical in determining safety of closure. By safely eliminating the large PDA, this treatment algorithm can halt the perilous combination of the large shunting from the PDA and PH in a population at high risk of morbidity and mortality.
DataPlay's mobile recording technology
NASA Astrophysics Data System (ADS)
Bell, Bernard W., Jr.
2002-01-01
A small rotating memory device which utilizes optical prerecorded and writeable technology to provide a mobile recording technology solution for digital cameras, cell phones, music players, PDA's, and hybrid multipurpose devices have been developed. This solution encompasses writeable, read only, and encrypted storage media.
Szlag, David C; Sinclair, James L; Southwell, Benjamin; Westrick, Judy A
2015-06-12
An environmental protection agency EPA expert workshop prioritized three cyanotoxins, microcystins, anatoxin-a, and cylindrospermopsin (MAC), as being important in freshwaters of the United States. This study evaluated the prevalence of potentially toxin producing cyanobacteria cell numbers relative to the presence and quantity of the MAC toxins in the context of this framework. Total and potential toxin producing cyanobacteria cell counts were conducted on weekly raw and finished water samples from utilities located in five US states. An Enzyme-Linked Immunosorbant Assay (ELISA) was used to screen the raw and finished water samples for microcystins. High-pressure liquid chromatography with a photodiode array detector (HPLC/PDA) verified microcystin concentrations and quantified anatoxin-a and cylindrospermopsin concentrations. Four of the five utilities experienced cyanobacterial blooms in their raw water. Raw water samples from three utilities showed detectable levels of microcystins and a fourth utility had detectable levels of both microcystin and cylindrospermopsin. No utilities had detectable concentrations of anatoxin-a. These conventional plants effectively removed the cyanobacterial cells and all finished water samples showed MAC levels below the detection limit by ELISA and HPLC/PDA.
Data management using the personal digital assistant in an acute pain service.
Chan, S S; Chu, C P; Cheng, B C; Chen, P P
2004-02-01
Handheld personal digital assistants (PDA) are increasingly being used by physicians for a variety of information and data management purposes. We evaluated a PDA-based data management system for our acute pain service. A structured questionnaire survey was conducted to assess staff experience and attitude towards the paper system before the introduction of the PDA, and three months after introduction of the PDA system. We compared the time taken to conduct the acute pain round before and after the implementation of the PDA. The time saved in data management and the amount of paper saved were estimated. Data from 177 patients with a total of 635 acute pain follow-up visits were entered over a three-month period. User satisfaction, ease of access to drug reference and clinical guidelines were similar between the two systems. The respondents found that the PDA was easy to use but less so than the paper system (P = 0.007), in particular, when accessing a patient's cumulative data (P = 0.007). There was no missed follow-up or data entry with the use of PDA. The time taken to attend follow-up visits was similar for the two systems (Paper: 8.8 +/- 3.2 compared to PDA: 7.0 +/- 2.0 minutes, P = 0.151). The estimated annual amount of paper and time saved in data management was 650 sheets and 130 man-hours respectively. Our experience with the use of the PDA in APS was satisfactory. The PDA system can potentially reduce time and paper use and missed data entry and patient follow-up.
HPLC-PDA analysis and anti-inflammatory effects of Mori Cortex Radicis.
Seo, Chang-Seob; Lim, Hye-Sun; Jeong, Soo-Jin; Ha, Hyekyung; Shin, Hyeun-Kyoo
2013-10-01
Mori Cortex Radicis (MCR, Moraceae) is used traditionally in the treatment ofjaundice, hematemesis, edema, and pollakisuria in Korea. In this study, the antiinflammatory effects of MCR extract were investigated using RAW 264.7 cells. The simultaneous analysis of five components present (neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, and p-coumaric acid) in the MCR extract was performed using high-performance liquid chromatography (HPLC) coupled with photodiode array (PDA) detection. We determined the effects of MCR extract and its components on the production of nitric oxide (NO), prostaglandin E2 (PGE2), and mRNA expression of cyclooxygenase-2 (COX-2) in RAW 264.7 cells. MCR extract suppressed the production of NO and PGE2 in RAW 264.7 cells in a dose-dependent manner. None of the five components of the MCR extract had any influence on the production of NO. However, caffeic acid and p-coumaric acid inhibited the production of PGE2 and mRNA expression of COX-2 in RAW 264.7 cells. Our results suggest that MCR extract may offer potential as a therapeutic agent for the treatment of inflammation. The method we have established will help to improve the quality control of MCR extracts.
[Risk factors for patent ductus arteriosus in early preterm infants: a case-control study].
Du, Jin-Feng; Liu, Tian-Tian; Wu, Hui
2016-01-01
To investigate the risk factors for the occurrence of patent ductus arteriosus (PDA) and to provide a clinical basis for reducing the occurrence of PDA in early preterm infants. A total of 136 early preterm infants (gestational age≤32 weeks) who were hospitalized between January 2013 and December 2014 and diagnosed with hemodynamicalhy significant PDA (hs-PDA) were enrolled as the case group. Based on the matched case-control principle, 136 early preterm infants without hs-PDA were selected among those who were hospitalized within the same period at a ratio of 1:1 and enrolled as the control group. The two groups were matched for sex and gestational age. The basic information of neonates and maternal conditions during the pregnancy and perinatal periods were collected. Logistic regression analysis was performed to identify the risk factors for the development of PDA. Univariate analysis showed that neonatal infectious diseases, neonatal respiratory distress syndrome, decreased platelet count within 24 hours after birth, and low birth weight were associated with the development of hs-PDA (P<0.05). Multivariate conditional logistic regression analysis revealed that neonatal infectious diseases (OR=2.368) and decreased platelet count within 24 hours after birth (OR=0.996) were independent risk factors for hs-PDA. Neonatal infectious diseases and decreased platelet count within 24 hours after birth increase the risk of hs-PDA in early preterm infants.
Does patent ductus arteriosus affect feed tolerance in preterm neonates?
Patole, S K; Kumaran, V; Travadi, J N; Brooks, J M; Doherty, D A
2007-01-01
Patent ductus arteriosus (PDA), especially PDA with sepsis, has been reported as a risk factor for feed intolerance in preterm neonates. In this study, the start to full feeds interval was found to be longest in preterm neonates (
Cu(II)-Doped Polydopamine-Coated Gold Nanorods for Tumor Theranostics.
Liu, Shuwei; Wang, Lu; Lin, Min; Wang, Dandan; Song, Ziqi; Li, Shuyao; Ge, Rui; Zhang, Xue; Liu, Yi; Li, Zhimin; Sun, Hongchen; Yang, Bai; Zhang, Hao
2017-12-27
Gold nanorods (AuNRs) are potentially useful in tumor theranostics, but the poor stability, high toxicity, and rapid removal by the immune system seriously limit their theranostic applications. In our study, we demonstrate the fabrication of Cu(II)-doped polydopamine-coated AuNR (AuNR@CuPDA), which significantly improves the potentials in tumor theranostics. Besides the improvement of physiological stability and biocompatibility, the PDA shell increases the photothermal performance and prolongs the blood circulation time of AuNRs. The half-life of AuNRs during blood circulation increases from 0.7 to 4.5 h after PDA coating, and the injected dose per gram of tumor tissue is 4.6% ID g -1 for AuNR@CuPDA. In addition to computer tomography imaging, the loading of Cu(II) in PDA shell endows AuNR@CuPDA with magnetic resonance imaging function. Cu(II) doped in PDA shell also exhibits chemotherapeutic behavior, and the tumor inhibitor rate is 31.2%. Further combining 808 nm laser-driven photothermal therapy, tumors were completely ablated, and no recurrence was observed. Liver and renal functions tests and histological analysis of major organs confirm that AuNR@CuPDA is in good safety.
Personal digital assistant use by nurse practitioners: a descriptive study.
Stroud, Sally D; Smith, Carol A; Erkel, Elizabeth A
2009-01-01
We sought to describe the prevalence and patterns of use of personal digital assistants (PDAs) among active nurse practitioners (NPs). A descriptive correlational survey was conducted among NPs in the United States (N = 126). Participants were randomly selected from members of the American Academy of Nurse Practitioners who had listed a practice site on their application. Sixty-four percent of participants used PDAs. A drug reference was reported to be the most useful and frequently installed application. A large majority of PDA users believed that PDA use supported clinical decision making (91%), promoted patient safety (89%), and increased productivity (75%). Sixty-two percent predicted that PDA use would change their practice within the next 5 years. As innovative PDA applications with potential to improve patient outcomes become increasingly available, handheld computer skills will be a fundamental practice competency. To prevent errors in clinical decision making with quick access to PDA reference materials, NPs must critically evaluate the legitimacy and worth of PDA software programs. There is a critical need to evaluate the effectiveness of PDA use in clinical settings and develop an evidence base to guide use of the PDA in solving clinical problems.
Palanisamy, Selvakumar; Thirumalraj, Balamurugan; Chen, Shen-Ming; Wang, Yi-Ting; Velusamy, Vijayalakshmi; Ramaraj, Sayee Kannan
2016-01-01
We report a novel and sensitive amperometric sensor for chlorpromazine (CPZ) based on reduced graphene oxide (RGO) and polydopamine (PDA) composite modified glassy carbon electrode. The RGO@PDA composite was prepared by electrochemical reduction of graphene oxide (GO) with PDA. The RGO@PDA composite modified electrode shows an excellent electro-oxidation behavior to CPZ when compared with other modified electrodes such as GO, RGO and GO@PDA. Amperometric i-t method was used for the determination of CPZ. Amperometry result shows that the RGO@PDA composite detects CPZ in a linear range from 0.03 to 967.6 μM. The sensor exhibits a low detection limit of 0.0018 μM with the analytical sensitivity of 3.63 ± 0.3 μAμM–1 cm–2. The RGO@PDA composite shows its high selectivity towards CPZ in the presence of potentially interfering drugs such as metronidazole, phenobarbital, chlorpheniramine maleate, pyridoxine and riboflavin. In addition, the fabricated RGO@PDA modified electrode showed an appropriate recovery towards CPZ in the pharmaceutical tablets. PMID:27650697
Preparation and antibacterial properties of Ag@polydopamine/graphene oxide sheet nanocomposite
NASA Astrophysics Data System (ADS)
Zhou, Hao; Liu, Yunfang; Chi, Weidong; Yu, Changyuan; Yu, Yingjie
2013-10-01
Immobilization of silver nanoparticles (Ag NPs) on poly-dopamine (PDA) functionalized graphene oxide sheets (GOSs) were carried out by an easy in situ reduction method. The PDA layer was coated on the surface of the GOSs via the self-polymerization of dopamine under atmosphere condition. The PDA layer not only works as the chemisorption and reduction sites for silver ions to form Ag NPs but also stabilizes them. High-resolution transmission electron microscopy observation shows that the average size of the Ag NPs anchored on the PDA/GOS composite is about 2.8 nm. The inhibition zone diameter of the Ag@PDA/GOS nanocomposite is about 23.7 mm, whereas said diameter of the Ag NPs is only 18.5 mm. The minimum bactericidal concentration of the Ag@PDA/GOS nanocomposite is about 25 μg/ml that is only half of said concentration of the Ag NPs. The Ag@PDA/GOS nanocomposite exhibits an excellent antibacterial property.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ling, Yang; Li, Weizhen; Wang, Baoyu
Carbon nanotubes (CNTs) functionalized by a nanothin poly(dopamine) (PDA) layer were produced by a one-pot, nondestructive approach, with direct polymerization of dopamine on the CNT surface. The thickness of the PDA layer can be well-controlled by the reaction time and the proportion of dopamine, and this thickness is found to be the key factor in controlling the dispersion of CNTs and the extent of the interfacial interactions between the CNT@PDA and epoxy resin. SEM results indicated that the dispersion of CNTs in epoxy was improved significantly by coating a nanothin PDA layer onto the CNT surface. In agreeme nt withmore » this finding, the CNTs functionalized with the thinnest PDA layer provided the best mechanical and thermal properties. This result confirmed that a thinner PDA layer could provide optimized interfacial interactions between the CNT@PDA and epoxy matrix and weaken the self-agglomeration of CNTs, which led to an improved effective stress and heat transfer between the CNTs and the polymer matrix.« less
NASA Astrophysics Data System (ADS)
Zheng, Yu; Lu, Shixiang; Xu, Wenguo; He, Ge; Cheng, Yuanyuan; Yu, Tianlong; Zhang, Yan
2018-02-01
A three dimensional composite electrode consisted of reduced graphene oxide (rGO), polydopamine (PDA) and nickel foam (NF) (rGO/PDA/NF) was fabricated by immersing NF into PDA aqueous solution and then graphene oxide (GO) suspension solution respectively, and followed by annealing treatment. During the procedure, GO was coated on NF with assistance of cohesive effect of the PDA middle film, and the reduction of GO and nitrogen doping occurred simultaneously while annealing. Through XRD analyzing, the composites GO/PDA and rGO/PDA treated in experiment are amorphous. The resulted rGO/PDA/NF composite electrode was directly applied as a supercapacitor electrode and showed excellent electrochemical performance, with a high specific capacitance of 566.9 F g-1 at 1 A g-1, the maximum energy density of 172.7 W h kg-1 and a power density of 27.2 kW kg-1 in 1 mol L-1 Na2SO4 electrolyte.
Coil occlusion of residual shunts after surgical closure of patent ductus arteriosus.
Fujii, Yoko; Keene, Bruce W; Mathews, Kyle G; Atkins, Clarke E; Defrancesco, Teresa C; Hardie, Elizabeth M; Wakao, Yoshito
2006-12-01
OBJECTIVE; To describe use of coil embolization to occlude residual flow through a patent ductus arteriosus (PDA) after incomplete surgical ligation. Clinical study. Dogs (n=4) with continuous murmur after surgical ligation of PDA. After PDA ligation, residual ductal flow through the PDA was visible on color-flow Doppler examination and left ventricular end-diastolic diameter remained increased. Coil embolization by an arterial approach was performed to achieve complete occlusion of the PDA. Embolization coils were delivered without complications and hemodynamically successful occlusion was achieved. Doppler-visible flow resolved in 2 dogs within 3 months after embolization. Left ventricular end-diastolic diameter indexed to body weight decreased in all dogs. Transcatheter coil embolization appears to be a safe and minimally invasive procedure for complete occlusion of residual PDA flow after incomplete surgical ligation. Transcatheter coil embolization should be considered for correction of hemodynamically significant residual shunts in dogs that have incomplete PDA occlusion after open surgical ligation.
Poly[diaquatris(μ4-1,3-phenylenediacetato)dineodymium(III)
Gao, Zhu-Qing; Lv, Dong-Yu; Li, Hong-Ji; Gu, Jin-Zhong
2011-01-01
In the title coordination polymer, [Nd2(C10H8O4)3(H2O)2]n, each of the two NdIII ions is nine-coordinated by eight O atoms from six different 2,2′-(m-phenylene)diacetate (pda) bivalent anions and by one O atom from a water molecule, forming a distorted tricapped trigonal–prismatic coordination geometry. Eight NdIII ions and 12 pda ligands form a large [Nd8(pda)12] ring, and four NdIII ions and six pda ligands form a small [Nd4(pda)6] ring. These rings are further connected by the coordination interactions of pda ligands and NdIII, generating a three-dimensional supramolecular framework. PMID:21522305
The USU medical PDA initiative: the PDA as an educational tool.
Moore, Leon; Richardson, Bradley R; Williams, Robert W
2002-01-01
A medical personal digital assistant (PDA) initiative for healthcare students began in 2000 at the Uniformed Services University of the Health Sciences (USU). The University issued PDAs to Graduate School of Nursing (GSN) and School of Medicine (SOM) students. These devices were used to provide clinical reference material to the students, to facilitate clinical experience log collection, and the normal organizer functions of a PDA. Both medical and graduate nursing students were surveyed both before and during clinical training to determine the perceived usefulness of the PDA. A quantitative approach was utilized to emphasize the measurable variables.
Value of audio-enhanced handheld computers over paper surveys with adolescents.
Trapl, Erika S; Taylor, H Gerry; Colabianchi, Natalie; Litaker, David; Borawski, Elaine A
2013-01-01
To examine the impact of 3 data collection modes on the number of questions answered, data quality, and student preference. 275 urban seventh-grade students were recruited and randomly assigned to complete a paper survey (SAQ), PDA survey (PDA), or PDA survey with audio (APDA). Students completed a paper debriefing survey. APDA respondents completed significantly more questions compared to SAQ and PDA. PDA and APDA had significantly less missing data than did SAQ. No differences were found for student evaluation. Strong benefits may be gained by the use of APDA for adolescent school-based data collection.
Wang, Kai; Luo, Ying
2013-07-08
As one important category of biological molecules on the cell surface and in the extracellular matrix (ECM), glycosaminoglycans (GAGs) have been widely studied for biomedical applications. With the understanding that the biological functions of GAGs are driven by the complex dynamics of physiological and pathological processes, methodologies are desired to allow the elucidation of cell-GAG interactions with molecular level precision. In this study, a microtiter plate-based system was devised through a new surface modification strategy involving polydopamine (PDA) and GAG molecules functionalized with hydrazide chemical groups. A small library of GAGs including hyaluronic acid (with different molecular weights), heparin, and chondroitin sulfate was successfully immobilized via defined binding sites onto the microtiter plate surface under facile aqueous conditions. The methodology then allowed parallel studies of the GAG-modified surfaces in a high-throughput format. The results show that immobilized GAGs possess distinct properties to mediate protein adsorption, cell adhesion, and inflammatory responses, with each property showing dependence on the type and molecular weight of specific GAG molecules. The PDA-assisted immobilization of hydrazide-functionalized GAGs allows biomimetic attachment of GAG molecules and retains their bioactivity, providing a new methodology to systematically probe fundamental cell-GAG interactions to modulate the bioactivity and biocompatibility of biomaterials.
Masri, Samer; El Rassi, Issam; Arabi, Mariam; Tabbakh, Anas; Bitar, Fadi
2015-08-01
To compare the efficacy and safety of Amplatzer Duct Occluder II (ADOII) among the various patent ductus arteriosus (PDA) types, and to assess the association between development of aortic obstruction and the PDA type in terms of measurable parameters as the device angulation and distance of upper end protrusion into the aortic lumen. Retrospective cohort study involving 50 consecutive subjects who underwent ADO II device closure of PDA. The median age and weight at intervention were 13 months (5.5 months to 18 years) and 11 (6-67) kg respectively. The median smallest ductal diameter by angiography was 3.2 (1.9-5.4) mm. Thirty two patients had type A PDA, 5 had type C, 5 had type D, and 8 had type E. Residual shunt was seen in only 1 patient who had a tubular PDA and resolved within 2 months of the procedure. No device embolization or pulmonary side protrusion were noted. There was a 16% aortic protrusion rate. The median distance of protrusion of the upper end of the device into the aortic lumen was 3.1 (0-9) mm and the median angle formed between the aortic end of the device and the PDA take-off was 10.4 (0-80.6) degrees. These latter parameters of aortic obstruction were significantly higher in the non-conical PDA group as compared to the conical PDA. Nevertheless, there was no significant coarctation due to aortic retention disc protrusion. Device closure of PDA using the ADO II is a safe procedure for chosen types of PDA. We demonstrated a novel technique for objective assessment of device protrusion into the descending aorta based on measurable parameters. ADOII device closure of non-conical PDAs warrants closer follow ups. © 2015 Wiley Periodicals, Inc.
Sellmer, Anna; Bech, Bodil H; Bjerre, Jesper V; Schmidt, Michael R; Hjortdal, Vibeke E; Esberg, Gitte; Rittig, Søren; Henriksen, Tine B
2017-01-10
A patent ductus arteriosus (PDA) is frequently found in very preterm neonates and is associated with increased risk of morbidity and mortality. A shunt across a PDA can result in an unfavorable distribution of the cardiac output and may in turn result in poor renal perfusion. Urinary Neutrophil Gelatinase-associated Lipocalin (U-NGAL) is a marker of renal ischemia and may add to the evaluation of PDA. Our primary aim was to investigate if U-NGAL is associated with PDA in very preterm neonates. Secondary, to investigate whether U-NGAL and PDA are associated with AKI and renal dysfunction evaluated by fractional excretion of sodium (FENa) and urine albumin in a cohort of very preterm neonates. A cohort of 146 neonates born at a gestational age less than 32 weeks were consecutively examined with echocardiography for PDA and serum sodium, and urine albumin and sodium were measured on postnatal day 3 and U-NGAL and serum creatinine day 3 and 6. AKI was defined according to modified neonatal Acute Kidney Injury Network (AKIN) criteria. The association between U-NGAL and PDA was investigated. And secondly we investigated if PDA and U-NGAL was associated with AKI and renal dysfunction. U-NGAL was not associated with a PDA day 3 when adjusted for gestational age and gender. A PDA day 3 was not associated with AKI when adjusted for gestational age and gender; however, it was associated with urine albumin. U-NGAL was not associated with AKI, but was found to be associated with urine albumin and FENa. Based on our study U-NGAL is not considered useful as a diagnostic marker to identify very preterm neonates with a PDA causing hemodynamic changes resulting in early renal morbidity. The interpretation of NGAL in preterm neonates remains to be fully elucidated.
NASA Astrophysics Data System (ADS)
Wang, Zhiqiang; Ren, Ruirui; Song, Haojie; Jia, Xiaohua
2018-01-01
Carbon nanotubes (CNTs) decorated with uniform copper nanoparticles (Cu NPs) were successfully prepared via a facile approach towards surface modification of CNTs with spontaneous polydopamine (PDA). The structures and morphologies of the nanocomposites were investigated by different kinds of techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Cu/PDA/CNTs nanocomposites were fabricated by growing the Cu NPs with an average diameter of 5 nm on the surfaces of PDA-modified CNTs. The CNTs functionalized with PDA layer not only provide an anchoring platform for the Cu NPs immobilization, but also endow Cu/PDA/CNTs with good dispersion stability when Cu/PDA/CNTs nanocomposites were used as lubricant additive. The tribological performance of the nanocomposites as the rapeseed oil lubricant additive, as well as Cu NPs, CNTs, and Cu/CNTs, was also investigated using a MS-T3000 ball-on-disk tribometer. Results show that the 0.2 wt% Cu/PDA/CNTs nanoadditive simultaneously reduce the friction and wear by 33.5% and 23.7%, respectively, outperformed the tribological performance of Cu NPs, CNTs, and Cu/CNTs nanoadditives. In addition, the presence of active sites in Cu/PDA/CNTs was beneficial to reduce the time of running-in period, give rise to the fastest speed to be stable of the friction coefficient curve as compared to the other nanoadditives. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy of the worn surfaces lubricated by the soybean oil with Cu/PDA/CNTs nanocomposites showed that formation of low shear strength tribofilms containing Cu/PDA/CNTs nanocomposites and its self-lubricating property was key factor in reduction of the friction and protection against wear and deformation.
Slaughter, Jonathan L; Reagan, Patricia B; Bapat, Roopali V; Newman, Thomas B; Klebanoff, Mark A
2016-06-01
We surveyed neonatal leadership at 46 US children's hospitals via web-based survey to identify local preferences and concerns regarding indomethacin prophylaxis, nonsteroidal anti-inflammatory drug (NSAID) treatment, and patent ductus arteriosus (PDA) ligation. We received a 100 % survey response (N = 46). Practice guidelines for prophylactic indomethacin were reported at 28 % of NICUs, for NSAID treatment of PDA at 39 % and for surgical ligation at 27 %. Respondents noted intra-institutional practice variation for indomethacin prophylaxis (33 %), NSAID treatment (70 %), and PDA ligation (73 %). The majority of institutions did not prescribe indomethacin prophylaxis (72 %). For PDA treatment, indomethacin was preferred over ibuprofen (80 %). We validated our survey results via comparison with billing data as documented in the Pediatric Health Information System (PHIS) database, finding that survey responses directly correlated with local billing data (p < 0.0001). At institutions that did not typically administer NSAIDs for PDA closure or surgical PDA ligation, a lack of evidence for their effectiveness in improving long-term outcomes and the risk of treatment-associated adverse effects were the most often cited reasons. No consensus exists among providers at US children's hospitals regarding prophylactic indomethacin, NSAID treatment, or PDA ligation. Lack of evidence and safety concerns play a prominent role. • NSAIDs and surgical PDA ligation are efficacious in preventing intraventricular hemorrhage (IVH) and closing PDA in preterm infants, but have not been shown to improve long-term respiratory, neurodevelopmental, or mortality outcomes. What is New: • Practice preferences for indomethacin prophylaxis, NSAID, and surgical PDA treatment vary both among and within institutions. Lack of treatment effectiveness and the risk of adverse effects are major concerns.
NASA Astrophysics Data System (ADS)
Giel, V.; Perchacz, M.; Kredatusová, J.; Pientka, Z.
2017-01-01
Functionalised titanate nanotubes (TiNTs) were incorporated to poly(5,5-bisbenzimidazole-2,2-diyl-1,3-phenylene) (PBI) or poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) for improving the interfacial compatibility between the polymer matrix and inorganic material and for altering the gas separation performance of the neat polymer membranes. Functionalisation consisted in oxidative polymerisation of dopamine-hydrochloride on the surface of non-functionalised TiNTs. Transmission electron microscopy (TEM) confirmed that a thin polydopamine (PDA) layer was created on the surface of TiNTs. 1.5, 3, 6, and 9 wt.% of PDA-functionalised TiNTs (PDA-TiNTs) were dispersed to each type of polymer matrix to create so-called mixed matrix membranes (MMMs). Infrared spectroscopy confirmed that -OH and -NH groups exist on the surface of PDA-TiNTs and that the nanotubes interact via H-bonding with PBI but not with PPO. The distribution of PDA-TiNTs in the MMMs was to some extent uniform as scanning electron microscope (SEM) studies showed. Beyond, PDA-TiNTs exhibit positive effect on gas transport properties, resulting in increased selectivities of MMMs. The addition of nanotubes caused a decrease in permeabilities but an increase in selectivities. It is shown that 9 wt.% of PDA-TiNTs in PBI gave a rise to CO2/N2 and CO2/CH4 selectivities of 112 and 63 %, respectively. In case of PPO-PDA-TiNT MMMs, CO2/N2 and CO2/CH4 selectivity increased about 25 and 17 %, respectively. Sorption measurement showed that the presence of PDA-TiNTs in PBI caused an increase in CO2 sorption, whereas the influence on other gases is less noticeable.
Kiran, Viralam S; Tiwari, Ashish
2018-04-06
The aims of this study were to determine the incidence and correlates of left ventricular (LV) dysfunction amongst percutaneous patent ductus arteriosus (PDA) device closure patients, and to propose an indexed parameter for predicting LV dysfunction. In a retrospective cross-sectional analysis of 30 months duration, 447 patients who underwent PDA device closure were studied. The diameter of the PDA at the pulmonary artery end was measured in the angiograms in all patients and was indexed for their body surface area. The indexed PDA size was categorised into group A (1-2.9 mm/m², 35/447), B (3-5.9 mm/m², 254/447), C (6-8.9 mm/m², 66/447) and D (>9 mm/m², 35/447). Systolic LV function was evaluated using echocardiography at frequent intervals. Overall, 62.63% of the patients were female (280/447). At baseline, all 447 patients had normal LV function. LV dysfunction was seen in 102/447 (22.8%) patients with 2.8% in category A (1/35), 10.6% in category B (27/254), 34.1% in category C (42/123) and 91.4% in category D (32/35) after PDA device closure. Correlation of indexed PDA size and LV dysfunction was statistically significant (p<0.05). Accurate prediction of LV dysfunction is important in risk stratification, ICU management and counselling in PDA device closures. Indexed PDA size correlates well with post-procedural LV dysfunction. The authors propose a new classification of PDA utilising this accurate, reproducible and easy to perform parameter, which does not involve any extra cost, for risk stratification and early management in device closure of PDA.
Prevalence and management of patent ductus arteriosus in a pediatric medicaid cohort.
Tripathi, Avnish; Black, George B; Park, Yong-Moon Mark; Jerrell, Jeanette M
2013-09-01
Widespread use of echocardiography has made earlier diagnosis of patent ductus arteriosus (PDA) possible, but pharmacological or surgical intervention is highly variable. Herein, we investigate the prevalence of PDA and its management in a routine care system. A 15-year retrospective dataset (1996-2010) was analyzed. Selection criteria included age ≤17 years, enrollees in South Carolina State Medicaid, and diagnosed as having PDA on 1 or more service visits to a pediatrician or pediatric cardiologist. The 15-year treated prevalence rate of PDA was 0.25/1000 pediatric cases of congenital heart disease (CHD). PDA was more prevalent in non-African American patients (adjusted odds ratio [aOR]: 1.12), but not in females after controlling for all other CHDs diagnosed in the cohort. Associated CHDs were present in 57.6% of the cases, primarily atrial or ventricular septal defects, and fewer patients (5.5%) developed pulmonary hypertension. Of 3627 PDA cases examined, 70.0% received no medications or PDA repair. Therapeutic ibuprofen was used for closure in 24.4% of the cases, and a PDA repair was performed in 7.8%. Younger children (aOR: 0.82), those who received an atrial septal defect closure (aOR: 5.18), and those who were treated with digoxin (aOR: 1.86) or with diuretics or preload/afterload reducing agents (ie, calcium channel blockers or angiotensin-converting enzyme inhibitors) (aOR: 5.72) were significantly more likely to have a PDA repair procedure. The majority of diagnosed PDA cases did not require pharmacological or surgical intervention. Those receiving pharmacological or surgical intervention were treated conservatively in relation to the presence of distress symptoms or concomitant CHDs requiring intervention. © 2013 Wiley Periodicals, Inc.
Shi, Jiafu; Yang, Chen; Zhang, Shaohua; Wang, Xiaoli; Jiang, Zhongyi; Zhang, Wenyan; Song, Xiaokai; Ai, Qinghong; Tian, Chunyong
2013-10-23
Microcapsules with diverse wall structures may exhibit different performance in specific applications. In the present study, three kinds of mussel-inspired polydopamine (PDA) microcapsules with different wall structures have been prepared by a template-mediated method. More specifically, three types of CaCO3 microspheres (poly(allylamine hydrochloride), (PAH)-doped CaCO3; pure-CaCO3; and poly(styrene sulfonate sodium), (PSS)-doped CaCO3) were synthesized as sacrificial templates, which were then treated by dopamine to obtain the corresponding PDA-CaCO3 microspheres. Through treating these microspheres with disodium ethylene diamine tetraacetic acid (EDTA-2Na) to remove CaCO3, three types of PDA microcapsules were acquired: that was (1) PAH-PDA microcapsule with a thick (∼600 nm) and highly porous capsule wall composed of interconnected networks, (2) pure-PDA microcapsule with a thick (∼600 nm) and less porous capsule wall, (3) PSS-PDA microcapsule with a thin (∼70 nm) and dense capsule wall. Several characterizations confirmed that a higher degree in porosity and interconnectivity of the capsule wall would lead to a higher mass transfer coefficient. When serving as the carrier for catalase (CAT) immobilization, these enzyme-encapsulated PDA microcapsules showed distinct structure-related activity and stability. In particular, PAH-PDA microcapsules with a wall of highly interconnected networks displayed several significant advantages, including increases in enzyme encapsulation efficiency and enzyme activity/stability and a decrease in enzyme leaching in comparison with other two types of PDA microcapsules. Besides, this hierarchically structured PAH-PDA microcapsule may find other promising applications in biocatalysis, biosensors, drug delivery, etc.
NASA Astrophysics Data System (ADS)
Li, Bing; Chen, Ye; Ge, Xiaoming; Chai, Jianwei; Zhang, Xiao; Hor, T. S. Andy; Du, Guojun; Liu, Zhaolin; Zhang, Hua; Zong, Yun
2016-02-01
Transition metal and nitrogen co-doping into carbon is an effective approach to promote the catalytic activities towards the oxygen reduction reaction (ORR) and/or oxygen evolution reaction (OER) in the resultant electrocatalysts, M/N-C. The preparation of such catalysts, however, is often complicated and in low yield. Herein we report a robust approach for easy synthesis of M/N-C hybrids in high yield, which includes a mussel-inspired polymerization reaction at room temperature and a subsequent carbonization process. With the introduction of selected transition metal salts into an aqueous solution of dopamine (DA), the obtained mixture self-polymerizes to form metal-containing polydopamine (M-PDA) composites, e.g. Co-PDA, Ni-PDA and Fe-PDA. Upon carbonization at elevated temperatures, these metal-containing composites were converted into M/N-C, i.e. Co-PDA-C, Ni-PDA-C and Fe-PDA-C, respectively, whose morphologies, chemical compositions, and electrochemical performances were fully studied. Enhanced ORR activities were found in all the obtained hybrids, with Co-PDA-C standing out as the most promising catalyst with excellent stability and catalytic activities towards both ORR and OER. This was further proven in Zn-air batteries (ZnABs) in terms of discharge voltage stability and cycling performance. At a discharge-charge current density of 2 mA cm-2 and 1 h per cycle, the Co-PDA-C based ZnABs were able to steadily cycle up to 500 cycles with only a small increase in the discharge-charge voltage gap which notably outperformed Pt/C; at a discharge current density of 5 mA cm-2, the battery continuously discharged for more than 540 h with the discharge voltage above 1 V and a voltage drop rate of merely 0.37 mV h-1. With the simplicity and scalability of the synthetic approach and remarkable battery performances, the Co-PDA-C hybrid catalyst is anticipated to play an important role in practical ZnABs.Transition metal and nitrogen co-doping into carbon is an effective approach to promote the catalytic activities towards the oxygen reduction reaction (ORR) and/or oxygen evolution reaction (OER) in the resultant electrocatalysts, M/N-C. The preparation of such catalysts, however, is often complicated and in low yield. Herein we report a robust approach for easy synthesis of M/N-C hybrids in high yield, which includes a mussel-inspired polymerization reaction at room temperature and a subsequent carbonization process. With the introduction of selected transition metal salts into an aqueous solution of dopamine (DA), the obtained mixture self-polymerizes to form metal-containing polydopamine (M-PDA) composites, e.g. Co-PDA, Ni-PDA and Fe-PDA. Upon carbonization at elevated temperatures, these metal-containing composites were converted into M/N-C, i.e. Co-PDA-C, Ni-PDA-C and Fe-PDA-C, respectively, whose morphologies, chemical compositions, and electrochemical performances were fully studied. Enhanced ORR activities were found in all the obtained hybrids, with Co-PDA-C standing out as the most promising catalyst with excellent stability and catalytic activities towards both ORR and OER. This was further proven in Zn-air batteries (ZnABs) in terms of discharge voltage stability and cycling performance. At a discharge-charge current density of 2 mA cm-2 and 1 h per cycle, the Co-PDA-C based ZnABs were able to steadily cycle up to 500 cycles with only a small increase in the discharge-charge voltage gap which notably outperformed Pt/C; at a discharge current density of 5 mA cm-2, the battery continuously discharged for more than 540 h with the discharge voltage above 1 V and a voltage drop rate of merely 0.37 mV h-1. With the simplicity and scalability of the synthetic approach and remarkable battery performances, the Co-PDA-C hybrid catalyst is anticipated to play an important role in practical ZnABs. Electronic supplementary information (ESI) available: Schematic structure of ZnAB; photos of home-made ZnABs; EDX spectra and elemental mapping of M-PDA-C; N2 adsorption/desorption isotherms, high magnification TEM images of M-PDA-C, and RDE data of M-PDA-C, etc. See DOI: 10.1039/c5nr06538k
A Methodology to Compare Insulin Dosing Recommendations in Real-Life Settings.
Groat, Danielle; Grando, Maria A; Thompson, Bithika; Neto, Pedro; Soni, Hiral; Boyle, Mary E; Bailey, Marilyn; Cook, Curtiss B
2017-11-01
We propose a methodology to analyze complex real-life glucose data in insulin pump users. Patients with type 1 diabetes (T1D) on insulin pumps were recruited from an academic endocrinology practice. Glucose data, insulin bolus (IB) amounts, and self-reported alcohol consumption and exercise events were collected for 30 days. Rules were developed to retrospectively compare IB recommendations from the insulin pump bolus calculator (IPBC) against recommendations from a proposed decision aid (PDA) and for assessing the PDA's recommendation for exercise and alcohol. Data from 15 participants were analyzed. When considering instances where glucose was below target, the PDA recommended a smaller dose in 14%, but a larger dose in 13% and an equivalent IB in 73%. For glucose levels at target, the PDA suggested an equivalent IB in 58% compared to the subject's IPBC, but higher doses in 20% and lower in 22%. In events where postprandial glucose was higher than target, the PDA suggested higher doses in 25%, lower doses in 13%, and equivalent doses in 62%. In 64% of all alcohol events the PDA would have provided appropriate advice. In 75% of exercise events, the PDA appropriately advised an IB, a carbohydrate snack, or neither. This study provides a methodology to systematically analyze real-life data generated by insulin pumps and allowed a preliminary analysis of the performance of the PDA for insulin dosing. Further testing of the methodological approach in a broader diabetes population and prospective testing of the PDA are needed.
Letshwiti, Johannes Buca; Sirc, Jan; O'Kelly, Ruth; Miletin, Jan
2014-11-01
The aim of the study was to assess the role of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration as a predictor of patent ductus arteriosus (PDA) in very low birth weight infants beyond the first week of life. This was a prospective observational study; newborns with a birth weight < 1500 g were eligible for enrolment. Enrolled infants were screened by echocardiography on day seven of life for the presence of a PDA. This was paired with a blood sample for NT-proBNP level. Echocardiography and NT-proBNP levels were repeated at weekly intervals. The primary outcome was correlation between PDA and NT-proBNP level and between measurements of PDA significance and NT-proBNP. Sixty-nine neonates were enrolled following parental consent. The mean birth weight was 1119 ± 257 g and mean gestational age was 28.6 ± 2.6 weeks. Median NT-proBNP level on day seven was 11469 ng/l in infants with a PDA vs. 898 ng/l in infants without a PDA (p < 0.0001). There was a statistically significant correlation between PDA diameter and NT-proBNP level on day seven, day 14 and day 21. NT-proBNP concentration is significantly increased in infants with a PDA and correlates well with PDA diameter in the first three weeks of life.
Chao, Chia-Sheng; Wei, Jeng; Huang, Hurng-Wern; Yang, Shyh-Chyun
2014-07-01
Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C gene polymorphisms are associated with the risk of patent ductus arteriosus (PDA) congenital heart defects. This study aimed to determine the association of these polymorphisms in patients with isolated PDA and in non-PDA patients group without congenital heart disease. This retrospective case-controlled study was undertaken in 17 patients with isolated PDA and a control non-PDA group consisting of 34 subjects without congenital heart disease. MTHFR gene polymorphisms were analysed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, the genotype distribution of the MTHFR gene was compared among different ethnicities using the HapMap database. In contrast to the MTHFR C677T polymorphism, differences in the MTHFR A1298C genotype were observed between the two groups (P=0.002); a greater proportion of the PDA patients had the MTHFR 1298CC and 1298AA genotypes as compared to the non-PDA control group. After merging the data obtained from the Taiwanese participants with that from the HapMap database, genetic diversity of the MTHFR 1298AA genotype was observed. Thus, the MTHFR A1298C polymorphism is associated with isolated PDA in Taiwan. Larger studies are necessary to evaluate the prognostic value of determining MTHFR polymorphism in PDA. Copyright © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
A randomised placebo-controlled trial of early treatment of the patent ductus arteriosus.
Kluckow, Martin; Jeffery, Michele; Gill, Andy; Evans, Nick
2014-03-01
Failure of closure of the patent ductus arteriosus (PDA) may be associated with harm. Early cardiac ultrasound-targeted treatment of a large PDA may result in a reduction in adverse outcomes and need for later PDA closure with no increase in adverse effects. Multicentre, double-blind, placebo-controlled randomised trial. Three neonatal intensive care units in Australia. Eligible infants born <29 weeks were screened for a large PDA and received indomethacin or placebo before age 12 h. Death or abnormal cranial ultrasound. The trial ceased enrolment early due to lack of availability of indomethacin. 164 eligible infants were screened before 12 h; of the 92 infants with a large PDA, 44 were randomised to indomethacin and 48 to placebo. There was no difference in the main outcome between groups. Infants receiving early indomethacin had significantly less early pulmonary haemorrhage (PH) (2% vs 21%), a trend towards less periventricular/intraventricular haemorrhage (PIVH) (4.5% vs 12.5%) and were less likely to receive later open-label treatment for a PDA (20% vs 40%). The 72 non-randomised infants with a small PDA were at low risk of pulmonary haemorrhage and had an 80% spontaneous PDA closure rate. Early cardiac ultrasound-targeted treatment of a large PDA is feasible and safe, resulted in a reduction in early pulmonary haemorrhage and later medical treatment but had no effect on the primary outcome of death or abnormal cranial ultrasound. Australian New Zealand Clinical Trials Registry (ACTRN12608000295347).
Multipath for Agricultural and Rural Information Services in China
NASA Astrophysics Data System (ADS)
Ge, Ningning; Zang, Zhiyuan; Gao, Lingwang; Shi, Qiang; Li, Jie; Xing, Chunlin; Shen, Zuorui
Internet cannot provide perfect information services for farmers in rural regions in China, because farmers in rural regions can hardly access the internet by now. But the wide coverage of mobile signal, telephone line, and television network, etc. gave us a chance to solve the problem. The integrated pest management platform of Northern fruit trees were developed based on the integrated technology, which can integrate the internet, mobile and fixed-line telephone network, and television network, to provide integrated pest management(IPM) information services for farmers in rural regions in E-mail, telephone-voice, short message, voice mail, videoconference or other format, to users' telephone, cell phone, personal computer, personal digital assistant(PDA), television, etc. alternatively. The architecture and the functions of the system were introduced in the paper. The system can manage the field monitoring data of agricultural pests, deal with enquiries to provide the necessary information to farmers accessing the interactive voice response(IVR) in the system with the experts on-line or off-line, and issue the early warnings about the fruit tree pests when it is necessary according to analysis on the monitoring data about the pests of fruit trees in variety of ways including SMS, fax, voice and intersystem e-mail.The system provides a platform and a new pattern for agricultural technology extension with a high coverage rate of agricultural technology in rural regions, and it can solve the problem of agriculture information service 'last kilometer' in China. The effectiveness of the system was certified.
Reciprocal Translocation Observed in End-of-Production Cells of a Commercial CHO-Based Process.
Rouiller, Yolande; Kleuser, Beate; Toso, Emiliano; Palinksy, Wolf; Rossi, Mara; Rossatto, Paola; Barberio, Davide; Broly, Hervé
2015-01-01
During the validation of an additional working cell bank derived from a validated master cell bank to support the commercial production continuum of a recombinant protein, we observed an unexpected chromosomal location of the gene of interest in some end-of-production cells. This event-identified by fluorescence in situ hybridization and multicolour chromosome painting as a reciprocal translocation involving a chromosome region containing the gene of interest with its integral coding and flanking sequences-was unique, occurred probably during or prior to multicolour chromosome painting establishment, and was transmitted to the descending generations. Cells bearing the translocation had a transient and process-independent selective advantage, which did not affect process performance and product quality. However, this first report of a translocation affecting the gene of interest location in Chinese Hamster Ovary cells used for producing a biotherapeutic indicates the importance of the demonstration of the integrity of the gene of interest in end-of-production cells. The expression of recombinant therapeutic proteins in mammalian cells depends on the establishment of a cell line with the gene of interest integrated in the host genome and stably expressed over time. Before being used for commercial production, cell lines are submitted to a qualification program in order to ensure their phenotypic and genotypic characteristics and the efficacy and safety of the product. During the production life cycle of a therapeutic protein, additional cells banks have to be validated after exhaustion of the current qualified cell bank in order to support the commercial production continuum of the recombinant protein. It is during the validation of an additional working cell bank derived from a validated master cell bank that we detected a different chromosome bearing the gene of interest in a portion of cells at the end of the upstream production phase. In our case, this event did not affect the process performance, the product quality, or its safety profile, but it highlights the need to characterize the integrity of the gene of interest in end-of-production cells when producing recombinant proteins for human use. © PDA, Inc. 2015.
Gupta, Saurabh Kumar; Krishnamoorthy, Km; Tharakan, Jaganmohan A; Sivasankaran, S; Sanjay, G; Bijulal, S; Anees, T
2011-07-01
To evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) systolic and diastolic function in children. Limited studies are available on alteration in LV hemodynamics, especially diastolic function, after PDA closure. Thirty-two consecutive children with isolated PDA treated by trans-catheter closure were studied. The LV systolic and diastolic function were assessed by two-dimensional (2D) echocardiography and tissue Doppler imaging 1 day before the PDA closure, on day 1, and on follow-up. At baseline, none of the patients had LV systolic dysfunction. On day 1 post-PDA closure, 8 (25%) children developed LV systolic dysfunction. The baseline LV ejection fraction (LVEF), LV end-systolic dimension (LVESD), and PDA diastolic gradient predicted the post-closure LVEF. Patients who developed post-closure LV systolic dysfunction had poorer LV diastolic function than those who did not. LV diastolic properties improved after PDA closure; however, the improvement in LV diastolic properties lagged behind the improvement in the LV systolic function. All children were asymptomatic and had normal LVEF on follow up of >3 months. Percutaneous closure of PDA is associated with the reversible LV systolic dysfunction. Improvement in the LV diastolic function lags behind that in the LV systolic function.
Transcatheter closure of large patent ductus arteriosus using custom made devices.
Rohit, Manoj Kumar; Gupta, Ankur
2017-05-01
There has been a paradigm shift in the transcatheter closure of patent ductus arteriosus (PDA) over the last 45 years. With the availability of various coils, plugs and occluders, PDA of almost all shapes and sizes are amenable to transcatheter closure. However, very large PDA diagnosed late in life are being referred for surgical closure in the absence of availability of large size devices, especially in developing countries. In this case series, we have described four patients with large PDA, three of which were closed by transcatheter custom made PDA occluders. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Uedono, A.; Ikeuchi, K.; Yamabe, K.; Ohdaira, T.; Muramatsu, M.; Suzuki, R.; Hamid, A. S.; Chikyow, T.; Torii, K.; Yamada, K.
2005-07-01
Thin Hf0.6Si0.4Ox and Hf0.3Al0.7Ox films fabricated by metal-organic chemical-vapor deposition and atomic-layer-deposition techniques were characterized using monoenergetic positron beams. Measurements of the Doppler broadening spectra of annihilation radiation and the lifetime spectra of positions indicated that positrons annihilated from the trapped state by open volumes that exist intrinsically in amorphous structures of the films. For HfSiOx, the mean size of the open volumes and their size distribution decreased with increasing postdeposition annealing (PDA) temperature. For HfAlOx, although the overall behavior of the open volumes in response to annealing was similar to that for HfSiOx, PDA caused a separation of the mean size of the open volumes. When this separation occurred, the value of the line-shape parameter S increased, suggesting an oxygen deficiency in the amorphous matrix. This fragmentation of the amorphous matrix can be suppressed by decreasing the annealing time.
Learning PDA skills online is feasible and acceptable to clerkship students.
Strayer, Scott M; Williams, Pamela M; Stephens, Mark B; Yew, Kenneth S
2008-01-01
The feasibility and acceptability of teaching medical students to use PDA clinical decision support tools via a Web-based course have not been previously evaluated. A total of 119 third-year family medicine clerkship students completed a baseline survey on PDA use, attended an introductory PDA lecture, and were invited to voluntarily access a Web-based course through Blackboard. All students had been previously issued with PDAs in their second year. At baseline, 95% of students reported having removed their PDA from its box, 59% reported using it weekly, and 71% had loaded medical applications. From August 2006--March 2007, 36 students accessed the course 610 times (range 8-54). The PDA cases comprised 63% of hits, course resources 30% of hits, and course information 6% of hits. Students evaluated the course equally to other clerkship didactics. It is feasible and acceptable to students to teach PDA decision support tools in an online course. In our setting, for the minority of students who chose to learn online, the format was successful and met their needs.
The Role of Probabilistic Design Analysis Methods in Safety and Affordability
NASA Technical Reports Server (NTRS)
Safie, Fayssal M.
2016-01-01
For the last several years, NASA and its contractors have been working together to build space launch systems to commercialize space. Developing commercial affordable and safe launch systems becomes very important and requires a paradigm shift. This paradigm shift enforces the need for an integrated systems engineering environment where cost, safety, reliability, and performance need to be considered to optimize the launch system design. In such an environment, rule based and deterministic engineering design practices alone may not be sufficient to optimize margins and fault tolerance to reduce cost. As a result, introduction of Probabilistic Design Analysis (PDA) methods to support the current deterministic engineering design practices becomes a necessity to reduce cost without compromising reliability and safety. This paper discusses the importance of PDA methods in NASA's new commercial environment, their applications, and the key role they can play in designing reliable, safe, and affordable launch systems. More specifically, this paper discusses: 1) The involvement of NASA in PDA 2) Why PDA is needed 3) A PDA model structure 4) A PDA example application 5) PDA link to safety and affordability.
Na, Kyoung-Sae; Ham, Byung-Joo; Lee, Min-Soo; Kim, Leen; Kim, Yong-Ku; Lee, Heon-Jeong; Yoon, Ho-Kyoung
2013-08-01
Patients with panic disorder with agoraphobia (PDA) have clinical symptoms such as the fear of being outside or of open spaces from which escape would be difficult. Although recent neurobiological studies have suggested that fear conditioning and extinction are associated with PDA, no study has examined the possible structural abnormalities in patients with PDA. This preliminary study compares the gray matter volume among patients with PDA, those with panic disorder without agoraphobia (PDW), and healthy controls (HC) using high-resolution 3.0 T magnetic resonance imaging (MRI) with voxel-based morphometry (VBM). Compared with HC, patients with PDA showed decreased gray matter volume in their left medial orbitofrontal gyrus. However, differences were not found in the gray matter volumes of patients with PDW and whole panic disorder compared with HC. These findings suggest that the phobic avoidance found in patients with PDA arise from abnormalities in the medial orbitofrontal cortex, which plays an important role in fear extinction. Future studies should investigate the neuroanatomical substrates of PDA and distinguish them from those of PDW. Copyright © 2013 Elsevier Inc. All rights reserved.
Ling, Yang; Li, Weizhen; Wang, Baoyu; ...
2016-03-29
Carbon nanotubes (CNTs) functionalized by a nanothin poly(dopamine) (PDA) layer were produced by a one-pot, nondestructive approach, with direct polymerization of dopamine on the CNT surface. The thickness of the PDA layer can be well-controlled by the reaction time and the proportion of dopamine, and this thickness is found to be the key factor in controlling the dispersion of CNTs and the extent of the interfacial interactions between the CNT@PDA and epoxy resin. SEM results indicated that the dispersion of CNTs in epoxy was improved significantly by coating a nanothin PDA layer onto the CNT surface. In agreeme nt withmore » this finding, the CNTs functionalized with the thinnest PDA layer provided the best mechanical and thermal properties. This result confirmed that a thinner PDA layer could provide optimized interfacial interactions between the CNT@PDA and epoxy matrix and weaken the self-agglomeration of CNTs, which led to an improved effective stress and heat transfer between the CNTs and the polymer matrix.« less
Janz-Robinson, Estella M; Badawi, Nadia; Walker, Karen; Bajuk, Barbara; Abdel-Latif, Mohamed E
2015-11-01
To compare neurodevelopmental outcomes of extremely preterm infants diagnosed with patent ductus arteriosus (PDA) who were treated medically or surgically and those who were not diagnosed with PDA or who did not undergo treatment for PDA. This retrospective population-based cohort study used data from a geographically defined area in New South Wales and the Australian Capital Territory served by a network of 10 neonatal intensive care units. Patients included all preterm infants born at <29 completed weeks of gestation between 1998 and 2004. Moderate/severe functional disability at 2-3 years corrected age was defined as developmental delay, cerebral palsy requiring aids, sensorineural or conductive deafness (requiring bilateral hearing aids or cochlear implant), or bilateral blindness (best visual acuity of <6/60). Follow-up information at age 2-3 years was available for 1473 infants (74.8%). Compared with infants not diagnosed with a PDA or who did not receive PDA treatment for PDA, those with medically treated PDA (aOR, 1.622; 95% CI, 1.199-2.196) and those with surgically treated PDA (aOR, 2.001; 95% CI, 1.126-3.556) were at significantly greater risk for adverse neurodevelopmental outcomes at age 2-3 years. Our results demonstrate that treatment for PDA may be associated with a greater risk of adverse neurodevelopmental outcome at age 2-3 years. This was particularly so among infants born at <25 weeks gestation. These results may support permissive tolerance of PDAs; however, reasons for this association remain to be elucidated through carefully designed prospective trials. Copyright © 2015 Elsevier Inc. All rights reserved.
König, Kai; Guy, Katelyn J; Drew, Sandra M; Barfield, Charles P
2015-04-01
B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NTproBNP) have been shown to correlate with the size of the patent ductus arteriosus (PDA) in preterm infants. We investigated whether BNP or NTproBNP was more closely correlated with PDA size. This prospective observational study included preterm infants born <32 weeks' gestation who had an echocardiogram performed within the first four days of life. Blood samples were taken simultaneously for BNP and NTproBNP measurements prior to echocardiographic examination. Of the 60 infants recruited, 58 had complete data sets. The cohort's mean and standard deviation (SD) gestational age was 27(+3) (2(+2)) weeks, the mean (SD) birthweight was 1032 (315) grams, and 46 (79.3%) infants had a PDA with a mean (SD) diameter of 3.2 (0.9) mm. Median and interquartile range (IQR) BNP levels were 486.5 (219-1316) pg/mL for infants with a PDA and 190 (95.5-514.5) pg/mL for infants without a PDA. Median (IQR) NTproBNP levels were 10 858.5 (6319-42 108) pg/mL for infants with a PDA and 7488 (3363-14 227.5) pg/mL for infants without a PDA. Both BNP (R = 0.35, p = 0.0066) and NTproBNP (R = 0.31, p = 0.018) were significantly correlated with PDA size. BNP and NTproBNP are similarly useful for assessing PDA size in preterm infants. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Zhang, Hong; Dan, Zheng; Ding, Zhi-Jie; Lao, Yuan-Zhi; Tan, Hong-Sheng; Xu, Hong-Xi
2016-10-01
A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry. Experimental and calculated ECD spectra were used to determine the absolute configurations. The results of wound healing and transwell migration assay showed that oblongixanthones D (1), E (2), and oblongifolin L (9) have the ability to inhibit cancer cell migration in lower cytotoxic concentrations. Western blotting results showed that these compounds exhibited an anti-metastasis effect mainly through downregulating RAF protein levels. In addition, 2 and 9 could inhibit phospho-MEK and phospho-ERK at downstream. Moreover, 1, 2, and 9 could inhibit snail protein level, suggesting that they could regulate the EMT pathway.
Who’s Using PDAs? Estimates of PDA Use by Health Care Providers: A Systematic Review of Surveys
El Emam, Khaled
2006-01-01
Background Personal digital assistants (PDAs) find many uses in health care. Knowing rates of collective PDA use among health care providers is an important guiding step to further understanding those health care contexts that are most suited to PDA use and whether PDAs provide improved health outcomes. Objectives The objectives of this study were to estimate current and future PDA use among health care providers and to discuss possible implications of that use on choice of technology in clinical practice and research. Methods This study was a systematic review of PDA usage surveys. Surveys were identified as part of an ongoing systematic review on the use of handheld devices. Reports from eight databases covering both biomedical sciences and engineering (1993-2006) were screened against distinct eligibility criteria. Data from included surveys were extracted and verified in a standardized way and were assessed descriptively. Results We identified 23 relevant surveys, 15 of which were derived from peer-reviewed journals. This cohort of surveys was published between 2000 and 2005. Overall, since 1999, there is clear evidence of an increasing trend in PDA use. The current overall adoption rate for individual professional use ranges between 45% and 85%, indicating high but somewhat variable adoption, primarily among physicians. Conclusions Younger physicians and residents and those working in large and hospital-based practices are more likely to use a PDA. The adoption rate is now at its highest rate of increase according to a commonly accepted diffusion of innovations model. A common problem with the evaluation of information technology is that use frequently precedes research. This is the case here, in which PDA adoption rates are already high and projections are for rapid growth in the short term. In general, it appears that professional PDA use in health care settings involves more administrative and organizational tasks than those related to patient care, perhaps signaling where the growth in adoption is most likely to occur. We conclude that physicians are likely accustomed to using a PDA, and, therefore, technology expertise will probably not be a barrier to implementing PDA applications. However, there is an urgent need to evaluate the effectiveness and efficiency of specific tasks using handheld technology to inform those developing and those using PDA applications. PMID:16867970
Computerized rounding in a community hospital surgery residency program.
Park, John; Tymitz, Kevin; Engel, Amy M; Welling, Richard E
2007-01-01
With the institution of the 80-hour work week, residency programs have worked to institute programs that decrease the time that residents spend in the hospital while maintaining patient safety. This study was intended to assess the amount of time saved using computerized patient information in the form of a personal data assistant (PDA). A community hospital surgical residency program with 22 residents initially collected data daily for 4 weeks without PDA use. Data included preround time, check-out time, total number of patients, number of medical/surgical patients, and number of intensive care unit patients. The definition of prerounding time was started when residents first began collecting information on their patients in the morning until 6:00 am. Check-out time started at 5:00 pm and lasted until the discussion of patient care with the night team had finished. Residents were then given PDAs allowing immediate up-to-date access to patient information, which most importantly included current vital signs, laboratory data, radiological dictations, medication lists, and fluid intake and output. After a 4-week acquaintance period with the PDA had passed, data were again collected from the residents daily for 4 weeks. Daily averages for each week and an overall total average were calculated. Daily averages were also calculated for each PGY level. Paired t-tests compared the pre-PDA and post-PDA total averages. No significant difference was found between the total number of patients pre-PDA and post-PDA (7.6 and 7.6, respectively, p = 0.98), the average number of medical/surgical patients (4.7 and 7.1, respectively, p = 0.16), or the average number of intensive care unit patients (2.6 and 0.4, respectively, p = 0.06). Also, no significant difference was found between pre-PDA and post-PDA with average check-out time (24.5 minutes and 21.9 minutes, respectively, p = 0.06). However, a significant decrease in rounding time occurred with pre-PDA round time at 50.5 minutes and post-PDA round time at 40.7 minutes (p = 0.02). Results of this study support the hypothesis that the prerounding time dramatically decreases with the PDA compared to without. Not only does this decrease in time help to keep residents under the 80-hour work week rule, but also it helps to eliminate much of the confusion that can cause patient safety issues.
A review of stent’s failure on patent ductus arteriosus
NASA Astrophysics Data System (ADS)
Lazim, Zulfaqih; Ismail, Al Emran; Taib, Ishkrizat; Atan, Bainun Akmal Mohd
2017-01-01
This paper presents a review of stent’s failure on patent ductus arteriosus (PDA). Ductus arteriosus (DA) is an opening for newborn babies and some patient that experienced cynotic congenital heart disease (CCHD) should maintain the duct opening for survival. To date, there are no specific research on mechanical stent failure study at DA. The challenging of the stent implantation on PDA is the PDA morphology. The failure of stent in term of stent fracture have been reported and reviewed in this paper. Furthermore, the failure prediction of stent is important for further stent design development. The morphology of PDA, stent type and material used in PDA and method for accessing the failure of stent is reviewed.
Infusing PDA technology into nursing education.
White, Ann; Allen, Patricia; Goodwin, Linda; Breckinridge, Daya; Dowell, Jeffery; Garvy, Ryan
2005-01-01
Use of the personal digital assistant (PDA) has been infused into the accelerated baccalaureate program at Duke University to help prepare nursing students for professional practice. The authors provide an overview of the use of PDAs in the classroom, laboratory, and clinical setting. Technical aspects of PDA infusion and steps to ensure regulatory compliance are explored. Benefits of PDA use by both faculty and students in the program and challenges met with the infusion of this technology are also described.
Nonhomogeneous results in place learning among panic disorder patients with agoraphobia.
Gorini, Alessandra; Schruers, Koen; Riva, Giuseppe; Griez, Eric
2010-10-30
Patients affected by panic disorder with agoraphobia (PDA) often suffer from visuo-spatial disturbances. In the present study, we tested the place-learning abilities in a sample of 31 PDA patients compared to 31 healthy controls (CTR) using the computer-generated arena (C-G Arena), a desktop-based computer program developed at the University of Arizona (Jacobs et al 1997, for further detail about the program, see http://web.arizona.edu/~arg/data.html). Subjects were asked to search the computer-generated space, over several trials, for the location of a hidden target. Results showed that control subjects rapidly learned to locate the invisible target and consistently returned to it, while PDA patients were divided in two subgroups: some of them (PDA-A) were as good as controls in place learning, while some others (PDA-B) were unable to learn the correct strategies to find the target. Further analyses revealed that PDA-A patients were significantly younger and affected by panic disorder from less time than PDA-B, indicating that age and duration of illness can be critical factors that influence the place-learning abilities. The existence of two different subgroups of PDA patients who differ in their spatial orientation abilities could provide new insight into the mechanisms of panic and open new perspectives in the cognitive-behavioral treatment of this diffuse and disabling disorder. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Saida, Ken; Nakamura, Tomohiko; Hiroma, Takehiko; Takigiku, Kiyohiro; Yasukochi, Satoshi
2013-10-01
Patent ductus arteriosus (PDA) is common in premature infants. In very low birth weight infants (VLBWI), PDA requires surgical therapy in many cases. It is unclear to know at-risk infants showing cardio-dysfunction after PDA surgery. The purpose of this study was to identify at-risk infants showing cardio-dysfunction after surgery for patent ductus arteriosus (PDA). We examined the relationship between left ventricular (LV) performance before and after PDA ligation in a retrospective observational cohort study. We studied 64 preterm neonates with symptomatic PDA before and after surgical ligation. Echocardiographic examinations were performed pre- and postoperatively. M-mode measurements included left ventricular internal dimension in end-diastole (LVIDd) and LV fractional shortening (FS). All cases showed decreased LVFS after PDA closure. Most cases (49/64, 77%) showed postoperative FS decreased to below normal (<28%). Preoperative relative LVIDd was significantly larger in abnormal FS infants (137 ± 18%) than in normal FS infants (118 ± 11%; p<0.01). A cut-off value of preoperative relative LVIDd (absolute LVIDd/normal value) for predicting postoperative cardio-dysfunction was 127.4% (sensitivity, 0.735; specificity, 0.933; area under curve, 0.817). Determination of preoperative LVIDd might facilitate earlier identification of infants needing early PDA surgery and postoperative intensive care. © 2013 Elsevier Ireland Ltd. All rights reserved.
A spectroscopic study of the chromatic properties of GafChromicEBT3 films.
Callens, M; Crijns, W; Simons, V; De Wolf, I; Depuydt, T; Maes, F; Haustermans, K; D'hooge, J; D'Agostino, E; Wevers, M; Pfeiffer, H; Van Den Abeele, K
2016-03-01
This work provides an interpretation of the chromatic properties of GafChromicEBT3 films based on the chemical nature of the polydiacetylene (PDA) molecules formed upon interaction with ionizing radiation. The EBT3 films become optically less transparent with increasing radiation dose as a result of the radiation-induced polymerization of diacetylene monomers. In contrast to empirical quantification of the chromatic properties, less attention has been given to the underlying molecular mechanism that induces the strong decrease in transparency. Unlaminated GafChromicEBT3 films were irradiated with a 6 MV photon beam to dose levels up to 20 Gy. The optical absorption properties of the films were investigated using visible (vis) spectroscopy. The presence of PDA molecules in the active layer of the EBT3 films was investigated using Raman spectroscopy, which probes the vibrational modes of the molecules in the layer. The vibrational modes assigned to PDA's were used in a theoretical vis-absorption model to fit our experimental vis-absorption spectra. From the fit parameters, one can assess the relative contribution of different PDA conformations and the length distribution of PDA's in the film. Vis-spectroscopy shows that the optical density increases with dose in the full region of the visible spectrum. The Raman spectrum is dominated by two vibrational modes, most notably by the ν(C≡C) and the ν(C=C) stretching modes of the PDA backbone. By fitting the vis-absorption model to experimental spectra, it is found that the active layer contains two distinct PDA conformations with different absorption properties and reaction kinetics. Furthermore, the mean PDA conjugation length is found to be 2-3 orders of magnitude smaller than the crystals PDA's are embedded in. Vis- and Raman spectroscopy provided more insight into the molecular nature of the radiochromic properties of EBT3 films through the identification of the excited states of PDA and the presence of two PDA conformations. The improved knowledge on the molecular composition of EBT3's active layer provides a framework for future fundamental modeling of the dose-response.
Using mHealth Technology to Enhance Self-Monitoring for Weight Loss A Randomized Trial
Burke, Lora E.; Styn, Mindi A.; Sereika, Susan M.; Conroy, Molly B.; Ye, Lei; Glanz, Karen; Sevick, Mary Ann; Ewing, Linda J.
2012-01-01
Background Self-monitoring for weight loss has traditionally been performed with paper diaries. Technologic advances could reduce the burden of self-monitoring and provide feedback to enhance adherence. Purpose To determine if self-monitoring diet using a PDA only or the PDA with daily tailored feedback (PDA+FB), was superior to using a paper diary on weight loss and maintenance. Design The Self-Monitoring and Recording Using Technology (SMART) Trial was a 24-month RCCT; participants were randomly assigned to one of three self-monitoring groups. Setting/participants From 2006 to 2008, 210 overweight/obese adults (84.8% female, 78.1% white) were recruited from the community. Data were analyzed in 2011. Intervention Participants received standard behavioral treatment for weight loss which included dietary and physical activity goals, encouraged the use of self-monitoring, and was delivered in group sessions. Main outcome measures Percentage weight change at 24 months, adherence to self-monitoring over time. Results Study retention was 85.6%. The mean percentage weight loss at 24 months was not different among groups (paper diary: −1.94% [95% CI= −3.88, 0.01], PDA: −1.38% [95% CI= – 3.38, 0.62], PDA+FB: –2.32% [95% CI= –4.29, −0.35]); only the PDA+FB group (p=0.02) demonstrated a significant loss. For adherence to self-monitoring, there was a time-by-treatment group interaction between the combined PDA groups and the paper diary group (p=0.03) but no difference between PDA and PDA+FB groups (p=0.49). Across all groups, weight loss was greater for those who were adherent ≥60% versus <30% of the time, p<0.001. Conclusions PDA+FB use resulted in a small weight loss at 24 months; PDA use resulted in greater adherence to dietary self-monitoring over time. However, for sustained weight loss, adherence to self-monitoring is more important than the method used to self-monitor. A daily feedback message delivered remotely enhanced adherence and improved weight loss, which suggests that technology can play a role in improving weight loss. PMID:22704741
El-Farrash, Rania A; El Shimy, Mohammed S; El-Sakka, Abeer S; Ahmed, Manal G; Abdel-Moez, Dina G
2018-05-09
The objective of this study is to evaluate the efficacy and safety of oral paracetamol versus oral ibuprofen in the treatment of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. An interventional randomized case-control study, registered in ClinicalTrials.gov (NCT03265782), was conducted on 60 preterm infants with gestational age ≤34 weeks, postnatal age of 2-7 d and color Doppler echocardiographic evidence of hsPDA. Neonates were randomly assigned to two groups: 30 received oral ibuprofen and 30 received oral paracetamol. With failure of ductal closure, a second course of ibuprofen or paracetamol was given. The included newborns were subjected to detailed history, clinical examination, laboratory investigations that included complete blood count, renal, and liver function tests and echocardiographic evaluation. Oral paracetamol was as effective as ibuprofen for the closure of patent ductus arteriosus (PDA) with one course of treatment (p > .05). Moreover, oral paracetamol was superior to ibuprofen among neonates who needed second course of treatment with significant decrease in end diastolic flow velocity in the left pulmonary artery (0.35 ± 0.09 versus 0.19 ± 0.06, p = .014), right ventricular systolic pressure (40.50 ± 12.91 versus 20.50 ± 0.58, p = .016) and left atrium to aortic root ratio (1.23 ± 0.14 versus 1.07 ± 0.04, p = .046) when compared to ibuprofen group. Furthermore, the mean difference between pre- and post-treatment PDA size was significantly higher in the paracetamol group compared with ibuprofen group after the second course of treatment (1.07 ± 0.32 versus 0.73 ± 0.38, p = .024). Oral paracetamol was comparable with ibuprofen in terms of the rate of non-surgical ductal closure [28 (93.3%) versus 24 (80%), p = .591]. In addition, oral paracetamol was as safe as oral ibuprofen in terms of gastrointestinal perforation or bleeding, necrotizing enterocolitis, bronchopulmonary dysplasia, intraventricular hemorrhage, thrombocytopenia, hepatic or renal dysfunction. Oral paracetamol is an effective and well-tolerated first-line drug treatment for PDA in premature infants.
Montaner Ramón, Alicia; Galve Pradel, Zenaida; Fernández Espuelas, Cristina; Jiménez Montañés, Lorenzo; Samper Villagrasa, María Pilar; Rite Gracia, Segundo
2017-06-01
Patent ductus arteriosus (PDA) is a prevalent condition in preterm infants, and may be related to increased morbidity and mortality in the most immature newborns. Recent studies have examined the usefulness of brain natriuretic propeptide (proBNP) in the diagnosis of this pathology. The aim of the study was to evaluate the diagnostic efficacy of proBNP as a marker of hemodynamic overload in PDA. A retrospective study was conducted on preterm infants less than 32 weeks of gestation and/or weight less than 1500 grams. Echocardiogram and determination of proBNP levels were performed on all patients. Comparison was made by subgroups according to the presence of PDA and their haemodynamic characteristics. Of the 60 patients enrolled, 71.7% had PDA, of which 86% had haemodynamically significant patent ductus arteriosus (HS-PDA). All of them, but one, received medical treatment with ibuprofen or acetaminophen. Surgical closure was required in 29.7% of HS-PDA. Higher values of proBNP were found in patients with HS-PDA (33338±34494.47pg/mL; p=.000) compared with patients with closed or non-haemodynamically significant ductus arteriosus. Higher values were also found in patients who required surgical closure of PDA (30596.8±14910.9; p=.004). A greater decrease inproBNP levels was found in the group of patients which duct closure after pharmacological treatment (68±24.69% vs -12.22±99.4%; p=.030). ProBNP cutoff-level for HS-PDA was calculated by ROC curve and it was 9321.5pg/mL (Specificity: 100%, Sensitivity: 94.6%). ProBNP levels are related to the presence or absence of haemodynamically significant patent ductus arteriosus; and its variations with treatment response. High values are also related to the need for surgical closure of PDA. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.
den Toom, Marjolein L; Meiling, Agnes E; Thomas, Rachel E; Leegwater, Peter A J; Heuven, Henri C M
2016-06-13
Patent ductus arteriosus (PDA) is one of the most common congenital heart defects in dogs and is considered to be a complex, polygenic threshold trait for which a female sex predisposition has been described. Histological studies in dogs suggest that smooth muscle hypoplasia and asymmetry of the ductus tissue is the major cause of PDA. The Stabyhoun population is small and a predisposition for PDA has been suggested. The aims of this study were to describe the incidence, presentation from a clinical and histopathological perspective, and the population genetics of PDA in the Dutch Stabyhoun population. Forty-six cases were identified between 2000 and 2013. Between 2009 and 2012 the birth incidence of PDA in the Stabyhoun breed was 1.05 %. We estimated this to be 7-13 times higher than expected in the general dog population. Twelve of the 46 cases were part of a litter in which more than one sibling was affected. There was no sex predilection in our case cohort. Dogs diagnosed in adulthood showed severe cardiomegaly. The mean inbreeding coefficient of the reference population of Stabyhoun dogs was 31.4 % and the actual and effective numbers of founders were 14 and 6.5, respectively. The heritability of PDA was 0.51 (±0.09) for the reference population and 0.41 (±0.10) for the phenotyped population. Histopathology of sections of the PDA from two dogs showed findings similar to those described in other breeds although the smooth muscle of the ductus adjacent to the pulmonary artery appeared more hypoplastic than that in the ductus adjacent to the aorta. The Stabyhoun breed shows a strong predisposition for PDA. Apart from the absence of a higher incidence in females, no other significant features distinguish PDA in Stabyhouns from the condition in other dog breeds. Heritability and the mean inbreeding coefficient are both very high making the Dutch Stabyhoun breed particularly suited to the study of inherited risk factors for PDA.
Xi, Juqun; Da, Lanyue; Yang, Changshui; Chen, Rui; Gao, Lizeng; Fan, Lei; Han, Jie
2017-01-01
Nanoparticle drug delivery carriers, which can implement high performances of multi-functions, are of great interest, especially for improving cancer therapy. Herein, we reported a new approach to construct Mn 2+ -coordinated doxorubicin (DOX)-loaded poly(lactic- co -glycolic acid) (PLGA) nanoparticles as a platform for synergistic chemo-photothermal tumor therapy. DOX-loaded PLGA (DOX/PLGA) nanoparticles were first synthesized through a double emulsion-solvent evaporation method, and then modified with polydopamine (PDA) through self-polymerization of dopamine, leading to the formation of PDA@DOX/PLGA nanoparticles. Mn 2+ ions were then coordinated on the surfaces of PDA@DOX/PLGA to obtain Mn 2+ -PDA@DOX/PLGA nanoparticles. In our system, Mn 2+ -PDA@DOX/PLGA nanoparticles could destroy tumors in a mouse model directly, by thermal energy deposition, and could also simulate the chemotherapy by thermal-responsive delivery of DOX to enhance tumor therapy. Furthermore, the coordination of Mn 2+ could afford the high magnetic resonance (MR) imaging capability with sensitivity to temperature and pH. The results demonstrated that Mn 2+ -PDA@ DOX/PLGA nanoparticles had a great potential as a smart theranostic agent due to their imaging and tumor-growth-inhibition properties.
Sharma, Saumya; Khawaja, Mohamad; Ram, Manoj K; Goswami, D Yogi
2014-01-01
Summary The characterization of Langmuir–Blodgett thin films of 10,12-pentacosadiynoic acid (PDA) and their use in metal–insulator–metal (MIM) devices were studied. The Langmuir monolayer behavior of the PDA film was studied at the air/water interface using surface tension–area isotherms of polymeric and monomeric PDA. Langmuir–Blodgett (LB, vertical deposition) and Langmuir–Schaefer (LS, horizontal deposition) techniques were used to deposit the PDA film on various substrates (glass, quartz, silicon, and nickel-coated film on glass). The electrochemical, electrical and optical properties of the LB and LS PDA films were studied using cyclic voltammetry, current–voltage characteristics (I–V), and UV–vis and FTIR spectroscopies. Atomic force microscopy measurements were performed in order to analyze the surface morphology and roughness of the films. A MIM tunnel diode was fabricated using a PDA monolayer assembly as the insulating barrier, which was sandwiched between two nickel layers. The precise control of the thickness of the insulating monolayers proved critical for electron tunneling to take place in the MIM structure. The current–voltage characteristics of the MIM diode revealed tunneling behavior in the fabricated Ni–PDA LB film–Ni structures. PMID:25551052
Xi, Juqun; Da, Lanyue; Yang, Changshui; Chen, Rui; Gao, Lizeng; Fan, Lei; Han, Jie
2017-01-01
Nanoparticle drug delivery carriers, which can implement high performances of multi-functions, are of great interest, especially for improving cancer therapy. Herein, we reported a new approach to construct Mn2+-coordinated doxorubicin (DOX)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles as a platform for synergistic chemo-photothermal tumor therapy. DOX-loaded PLGA (DOX/PLGA) nanoparticles were first synthesized through a double emulsion-solvent evaporation method, and then modified with polydopamine (PDA) through self-polymerization of dopamine, leading to the formation of PDA@DOX/PLGA nanoparticles. Mn2+ ions were then coordinated on the surfaces of PDA@DOX/PLGA to obtain Mn2+-PDA@DOX/PLGA nanoparticles. In our system, Mn2+-PDA@DOX/PLGA nanoparticles could destroy tumors in a mouse model directly, by thermal energy deposition, and could also simulate the chemotherapy by thermal-responsive delivery of DOX to enhance tumor therapy. Furthermore, the coordination of Mn2+ could afford the high magnetic resonance (MR) imaging capability with sensitivity to temperature and pH. The results demonstrated that Mn2+-PDA@ DOX/PLGA nanoparticles had a great potential as a smart theranostic agent due to their imaging and tumor-growth-inhibition properties. PMID:28479854
Doocy, K R; Nelson, D A; Saunders, A B
2017-06-01
Advanced imaging modalities are becoming more widely available in veterinary cardiology, including the use of transesophageal echocardiography (TEE) during occlusion of patent ductus arteriosus (PDA) in dogs. The dog in this report had a complex history of attempted ligation and a large PDA that initially precluded device placement thereby limiting the options for PDA closure. Following a second thoracotomy and partial ligation, the morphology of the PDA was altered and device occlusion was an option. Angiographic assessment of the PDA was limited by the presence of hemoclips, and the direction of ductal flow related to the change in anatomy following ligature placement. Intra-operative TEE, in particular real-time three-dimensional imaging, was pivotal for assessing the PDA morphology, monitoring during the procedure, selecting the device size, and confirming device placement. The TEE images increased operator confidence that the size and location of the device were appropriate before release despite the unusual position. This report highlights the benefit of intra-operative TEE, in particular real-time three-dimensional imaging, for successful PDA occlusion in a complicated case. Copyright © 2017 Elsevier B.V. All rights reserved.
Rodriguez-Blanco, Silvia; Oulego-Erroz, Ignacio; Gautreaux-Minaya, Sandra; Perez-Muñuzuri, Alejandro; Couce-Pico, Maria Luz
2018-05-22
To assess whether early NT-ProBNP can identify the need for echocardiographic assessment of hemodynamically significant patent ductus arteriosus (HsPDA) in preterm infants. Prospective observational study of infants with a gestational age ≤32 weeks. Echocardiographic assessment and NT-proBNP measurement were performed at 48-96 h. ROC curves were generated to assess optimal cutoffs to detect HsPDA and predict the need for treatment. Eighty-five patients were included. HsPDA was present in 28 infants (37.6%), and 22 (25.8%) received treatment. The optimal NT-proBNP cutoff for the detection of HsPDA was 5099 pg/mL (sensitivity 94%, specificity 82%, area under the curve 0.941, P < 0.001). Only 1 child with NT-proBNP levels <5099 pg/mL was ultimately treated for PDA. NT-proBNP screening could have avoided 45 of 85 routine echocardiograms (53%). NT-proBNP screening at 48-96 h of life may identify preterm infants at low risk for HsPDA, improving PDA management.
NASA Astrophysics Data System (ADS)
Katsumata, Reika; Cho, Joon Hee; Zhou, Sunshine; Kim, Chae Bin; Dulaney, Austin; Janes, Dustin; Ellison, Christopher
Nature has engineered universal, catechol-containing adhesives that can be synthetically mimicked in the form of polydopamine (PDA). We exploited PDA to enable block copolymer (BCP) nanopatterning on a variety of soft material surfaces in a way that can potentially be applied to flexible electrical devices. Applying BCP nanopatterning to soft substrates is challenging because soft substrates are often chemically inert and possess incompatible low surface energies. In this study, we exploited PDA to enable the formation of BCP nanopatterns on a variety of surfaces such as Teflon, poly(ethylene terephthalate) (PET), and Kapton. While previous studies produced a PDA coating layer too rough for BCP nanopatterning, we succeeded in fabricating conformal and ultra-smooth surfaces of PDA by engineering the PDA coating process and post-sonication procedure. This chemically functionalized, biomimetic thin film (3 nm thick) served as a reactive platform for subsequently grafting a surface treatment to perpendicularly orient a lamellae-forming BCP layer. Furthermore, we demonstrated that a perfectly nanopatterned PDA-PET substrate can be bent without distorting or damaging the nanopattern in conditions that far exceeds typical bending curvatures in roll-to-roll manufacturing.
Sharma, Saumya; Khawaja, Mohamad; Ram, Manoj K; Goswami, D Yogi; Stefanakos, Elias
2014-01-01
The characterization of Langmuir-Blodgett thin films of 10,12-pentacosadiynoic acid (PDA) and their use in metal-insulator-metal (MIM) devices were studied. The Langmuir monolayer behavior of the PDA film was studied at the air/water interface using surface tension-area isotherms of polymeric and monomeric PDA. Langmuir-Blodgett (LB, vertical deposition) and Langmuir-Schaefer (LS, horizontal deposition) techniques were used to deposit the PDA film on various substrates (glass, quartz, silicon, and nickel-coated film on glass). The electrochemical, electrical and optical properties of the LB and LS PDA films were studied using cyclic voltammetry, current-voltage characteristics (I-V), and UV-vis and FTIR spectroscopies. Atomic force microscopy measurements were performed in order to analyze the surface morphology and roughness of the films. A MIM tunnel diode was fabricated using a PDA monolayer assembly as the insulating barrier, which was sandwiched between two nickel layers. The precise control of the thickness of the insulating monolayers proved critical for electron tunneling to take place in the MIM structure. The current-voltage characteristics of the MIM diode revealed tunneling behavior in the fabricated Ni-PDA LB film-Ni structures.
NASA Astrophysics Data System (ADS)
Rella, Simona; Mazzotta, Elisabetta; Caroli, Antonio; De Luca, Maria; Bucci, Cecilia; Malitesta, Cosimino
2018-07-01
Polydopamine (PDA) films have attracted a rapidly increasing research attention during the last years due to its simple and rapid deposition under alkaline conditions in substrate independent manner providing a universal coating for materials with different chemical and physical properties. Furthermore, this polymerized layer is enriched with functional groups that enable immobilization of primary amine or thiol-based biomolecules via a simple dipping process. Although these aspects justify PDA wide and successful application as a versatile coating for biomolecule immobilization, several aspects have not been deeply investigated leaving some key details unclear and thus limiting PDA practical applications. A number of approaches are commonly used for the growth of PDA, but the effect of deposition conditions on film properties, which in turn influence biomolecule immobilization has not been systematically investigated yet. In the present work, an extensive characterization by X-ray Photoelectron Spectroscopy (XPS) is performed on PDA coatings grown under different experimental conditions. Comparison of XPS data about elemental composition, distribution of functional groups and thickness of PDA coatings provided valuable information for identifying more suitable PDA coating for biomolecule anchoring, further explored by in vitro experiments.
Traiphol, Nisanart; Faisadcha, Kunruethai; Potai, Ruttayapon; Traiphol, Rakchart
2015-02-01
An ability to control the thermochromic behaviors of polydiacetylene (PDA)-based materials is very important for their utilization. Recently, our group has developed the PDA/zinc oxide (ZnO) nanocomposites, which exhibit reversible thermochromism (Traiphol et al., 2011). In this study, we present our continuation work demonstrating a rather simple method for fine tuning their color-transition temperature. The PDA/ZnO nanocomposites are prepared by varying photopolymerization time, which in turn affects the length of PDA conjugated backbone. We have found that the increase of photopolymerization time from 1 to 120min results in systematically decrease of the color-transition temperature from about 85 to 40°C. These PDA/ZnO nanocomposites still exhibit reversible thermochromism. The PDA/ZnO nanocomposites embedded in polyvinyl alcohol films show two-step color-transition processes, the reversible blue to purple and then irreversible purple to orange. Interestingly, the increase of photopolymerization time causes an increase of the irreversible color-transition temperature. Our method is quite simple and cheap, which can provide a library of PDA-based materials with controllable color-transition temperature. Copyright © 2014 Elsevier Inc. All rights reserved.
40 CFR 799.3300 - Unsubstituted phenylenediamines.
Code of Federal Regulations, 2012 CFR
2012-07-01
... (MVSL) or the mouse biochemical specific locus test (MBSL) shall be conducted for m-pda by gavage in... REQUIREMENTS Specific Chemical Test Rules § 799.3300 Unsubstituted phenylenediamines. (a) Identification of test substance. (1) The unsubstituted phenylenediamines (pda's), para-phenylenediamine (p-pda, CAS No...
40 CFR 799.3300 - Unsubstituted phenylenediamines.
Code of Federal Regulations, 2013 CFR
2013-07-01
... (MVSL) or the mouse biochemical specific locus test (MBSL) shall be conducted for m-pda by gavage in... REQUIREMENTS Specific Chemical Test Rules § 799.3300 Unsubstituted phenylenediamines. (a) Identification of test substance. (1) The unsubstituted phenylenediamines (pda's), para-phenylenediamine (p-pda, CAS No...
40 CFR 799.3300 - Unsubstituted phenylenediamines.
Code of Federal Regulations, 2014 CFR
2014-07-01
... (MVSL) or the mouse biochemical specific locus test (MBSL) shall be conducted for m-pda by gavage in... REQUIREMENTS Specific Chemical Test Rules § 799.3300 Unsubstituted phenylenediamines. (a) Identification of test substance. (1) The unsubstituted phenylenediamines (pda's), para-phenylenediamine (p-pda, CAS No...
Szlag, David C.; Sinclair, James L.; Southwell, Benjamin; Westrick, Judy A.
2015-01-01
An environmental protection agency EPA expert workshop prioritized three cyanotoxins, microcystins, anatoxin-a, and cylindrospermopsin (MAC), as being important in freshwaters of the United States. This study evaluated the prevalence of potentially toxin producing cyanobacteria cell numbers relative to the presence and quantity of the MAC toxins in the context of this framework. Total and potential toxin producing cyanobacteria cell counts were conducted on weekly raw and finished water samples from utilities located in five US states. An Enzyme-Linked Immunosorbant Assay (ELISA) was used to screen the raw and finished water samples for microcystins. High-pressure liquid chromatography with a photodiode array detector (HPLC/PDA) verified microcystin concentrations and quantified anatoxin-a and cylindrospermopsin concentrations. Four of the five utilities experienced cyanobacterial blooms in their raw water. Raw water samples from three utilities showed detectable levels of microcystins and a fourth utility had detectable levels of both microcystin and cylindrospermopsin. No utilities had detectable concentrations of anatoxin-a. These conventional plants effectively removed the cyanobacterial cells and all finished water samples showed MAC levels below the detection limit by ELISA and HPLC/PDA. PMID:26075379
Thanopoulos, Basil Vasilios D; Ninios, Vlassis; Dardas, Petros; Giannopoulos, Andreas; Deleanou, Dan; Iancovici, Silvia
2016-11-15
The standard technique of catheter closure of patent ductus arteriosus (PDA) may be associated with arterial complications particularly in small pediatric patients. The aim of this study was to evaluate whether catheter closure of PDA in small children using an exclusive venous approach is a safe and effective alternative to closure with the standard technique. One hundred-twelve patients, aged 2 to 24 months, were randomly assigned in a 1:1 ratio to catheter closure of PDA using the standard technique (group 1) and an exclusive venous approach (group 2), respectively. In group 2, the procedure was guided using hand injections of contrast media through the delivery sheath and 2-dimensional and color Doppler echocardiography. Group 1: the PDA diameter ranged from 2 to 5.5 mm and the device diameter ranged from 4 to 8 mm. The PDA occluders were permanently implanted in all patients. Five losses of the arterial pulses that were restored with intravenous infusion of heparin and recombinant tissue plasminogen activator (rtPA), and 4 groin hematomas were the main complications of the procedure. Group 2: the mean PDA diameter ranged from 2.5 to 6 mm and the device diameter ranged from 3 to 8 mm. The PDA occluders were permanently implanted in all but 2 patients. There were no complications. Complete echocardiographic closure of PDA at 1-month follow-up was observed in all 110 patients. Exclusive transvenous PDA occlusion is an effective and safe technique that prevents the arterial complications of the standard approach in small children. Copyright © 2016 Elsevier Inc. All rights reserved.
Backes, Carl H; Cheatham, Sharon L; Deyo, Grace M; Leopold, Scott; Ball, Molly K; Smith, Charles V; Garg, Vidu; Holzer, Ralf J; Cheatham, John P; Berman, Darren P
2016-02-12
Percutaneous closure of patent ductus arteriosus (PDA) in term neonates is established, but data regarding outcomes in infants born very preterm (<32 weeks of gestation) are minimal, and no published criteria exist establishing a minimal weight of 4 kg as a suitable cutoff. We sought to analyze outcomes of percutaneous PDA occlusion in infants born very preterm and referred for PDA closure at weights <4 kg. Retrospective analysis (January 2005-January 2014) was done at a single pediatric center. Procedural successes and adverse events were recorded. Markers of respiratory status (need for mechanical ventilation) were determined, with comparisons made before and after catheterization. A total of 52 very preterm infants with a median procedural weight of 2.9 kg (range 1.2-3.9 kg) underwent attempted PDA closure. Twenty-five percent (13/52) of infants were <2.5 kg. Successful device placement was achieved in 46/52 (88%) of infants. An adverse event occurred in 33% of cases, with an acute arterial injury the most common complication. We observed no association between weight at time of procedure and the risk of an adverse event. No deaths were attributable to the PDA closure. Compared to precatheterization trends, percutaneous PDA closure resulted in improved respiratory status, including less exposure to mechanical ventilation (mixed effects logistic model, P<0.01). Among infants born very preterm, percutaneous PDA closure at weights <4 kg is generally safe and may improve respiratory health, but risk of arterial injury is noteworthy. Randomized clinical trials are needed to assess clinically relevant differences in outcomes following percutaneous PDA closure versus alternative (surgical ligation) management strategies. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
Yang, Yankun; Zheng, Hong; Xu, Zhongying; Zhang, Gejun; Jin, Jinglin; Hu, Haibo; Tian, Tao; Zhou, Xianliang
2017-04-01
Limited data have reported the outcomes of percutaneous closure of patent ductus arteriosus (PDA) in patients with unilateral absence of pulmonary artery (UAPA). This study aimed to evaluate the symptomatology, diagnosis and therapy, especially the transcatheter closure of PDA in patients with PDA associated with UAPA. Patients diagnosed with PDA and UAPA were retrospectively enrolled from August 2010 through January 2016. Clinical data, treatment and follow-up information were evaluated. Thirteen patients (6 males and 7 females) were diagnosed with PDA associated with UAPA. Percutaneous closure was successfully conducted in 6 patients successfully. The median age was 7 years (7 months to 37 years). The mean diameter of the PDA and occluders were 4.7 ± 1.8mm (2-7mm) and 11.3 ± 3.9mm (6-14mm), respectively. The mean pulmonary artery pressure was 41.5 ± 13.5mmHg (25-62mmHg). The diameter of PDA has no relationship with the degree of pulmonary artery pressure (r = 0.239, P = 0.648). In 4 patients, systolic pulmonary arterial pressure decreased significantly after closure with 69.0 ± 10.7 versus 48.0 ± 11.3mmHg (P = 0.146), and also the mean pulmonary arterial pressure was 54.5 ± 5.7 mm Hg versus 30.5 ± 3.9mmHg (P = 0.04). In all, 1 patient had a trace residual shunt, which disappeared within 24 hours. In appropriate patients with PDA associated with UAPA, transcatheter closure of PDA has the potential to improve the pulmonary artery hypertension. Further follow-up is required to monitor the long-term outcomes. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.
Schmitz, Lothar; Stiller, Brigitte; Koch, Heike; Koehne, Petra; Lange, Peter
2004-02-01
In very low birth weight neonates, a left-to-right shunt via persistent ductus arteriosus (PDA) may interact with diastolic left ventricular function, but specific changes of Doppler parameters have yet to be reported. In a serial transmitral Doppler study, we investigated the impact of a PDA on diastolic function parameters. Twenty-two patients with and without PDA were examined on day 3.8+/-1 and day 14+/-2 after birth. By the first examination, 13 out of 22 patients had a PDA; by the second examination, the number was still 8 out of 22. Peak early and atrial flow velocities (44.8+/-15 and 50.1+/-13 cm/s, respectively) were higher (p<0.05) for neonates with PDA compared to those with closed duct (30.9+/-6 and 34.2 cm/s, respectively). Isovolumic relaxation time (IVRT) was shorter in neonates with PDA (45+/-7 ms, N=21) compared to those with a closed duct (55.3+/-5 ms, N=23) (p<0.01). IVRT correlated inversely with cardiac index (R=-0.79, p<0.01). All observed changes reversed to the normal range after closure of the PDA. When premature infants with a PDA experience a preload challenge, early and atrial peak velocities increase and IVRT shortens significantly. This coincidence of elevated transvalvular pressure differences and decreased IVRT in neonates with immature diastolic function can best be explained as a result of left atrial pressure elevation. Consequently, pulmonary venous pressure must be elevated, with its inherent effect on pulmonary capillary physiology. Thus, the monitoring of left ventricular diastolic function adds significant information to the care of preterm infants with a PDA.
Alenazi, Shehab Ahmed
2016-01-01
Evaluate the role of NT-proBNP levels in Preterm neonates suffering from PDA and used as a screening tool for predicting HsPDA and guiding physicians to consider early echocardiographic evaluation. This is a monocentric prospective blind study which was conducted at Arar Central Hospital, Ar'ar, Saudi Arabia, during the period between Jan 2014 to June 2014. Thirty-three (33) preterm infants born at less than 31 weeks of gestation or weighing less than 1200 g at birth infants were initially enrolled during a 6-month period. Blood samples were collected along with routine blood tests on days 1, 2, 3, and 7 of life for NT-proBNP analysis. Two echocardiographies were systematically performed on day two of life to ascertain about the status of Ductus Arteriosus. The Plasma NT-proBNP levels were high on day one of life and decline from day three to day seven of life except in those infants with significant hsPDA. Plasma NT-proNBP levels on day 2 of infants in the HsPDA group were significantly higher (<0.001) than those in non-HsPDA group. Echocardiogram parameters indicates the significant difference (p<0.002) in Left Atrial and Aortic ratio (LA/AO), Interventricular septum thickness (P<0.03), Left ventricular posterior wall thickness (p<0.05), diastole PDA gradient (p<0.005) between HsPDA and non-HsPDA. Plasma NT-proBNP level peaked during the first few days after birth and declined rapidly within a week. Therefore, its level may have a role as a screening tool to predict HsPDA and provide more information regarding its spontaneous closure or otherwise.
Patent ductus arteriosus in infants <29 weeks gestation--outcomes and factors affecting closure.
Popat, H; Kapoor, V; Travadi, J
2012-08-01
To determine Patent ductus arteriosus (PDA) closure rates for extremely preterm infants in a tertiary care centre, factors affecting response to indomethacin and outcomes of these infants relative to their PDA status. Neonatal intensive care unit in tertiary-care children's hospital. Retrospective medical record review. A retrospective chart review of all infants <29 weeks gestation between 1st Jan 2003 and 30th June 2006 was carried out. Multiple courses of standard intravenous indomethacin (dose: 0.2 mg/kg 12 hourly; 3 doses) followed by a tail course (0.1 mg/kg/day; 3 doses) were used to treat PDA depending on clinical and hemodynamic status. Data on demographic characteristics, PDA status, use of indomethacin, and outcome factors such as chronic lung disease and mortality were collected. A total of 166 infants were identified in the study period, of which 15 were excluded. The median gestation was 27 weeks [IQR (25, 28)] and the mean (SD) birthweight was 950 (244) grams. The remaining infants (n=151) were divided into three groups. Group1 (n=47): no or non-significant PDA, Group 2 (n=91): significant PDA closed after indomethacin treatment (= 1 course) and Group 3 (n=13): significant PDA not responding to indomethacin. The closure rate of PDA with indomethacin treatment (group 2) was 87%. A low gestational age < 26 weeks (OR 5.6, 95% CI 1.6-19.9) and female sex (OR 5.8, 95% CI 1.5-22.8) was associated with poor response to indomethacin in our study population. Multiple indomethacin courses using the standard dosing approach result in high PDA closure rates for infants < 29 weeks gestation.
Medication error reduction and the use of PDA technology.
Greenfield, Sue
2007-03-01
The purpose of this study was to determine whether nursing medication errors could be reduced and nursing care provided more efficiently using personal digital assistant (PDA) technology. The sample for this study consisted of junior and senior undergraduate baccalaureate nursing students. By self-selection of owning a PDA or not, students were placed in the PDA (experimental) group or the textbook (control) group, provided with a case study to read, and asked to answer six questions (i.e., three medication administration calculations and three clinical decisions based on medication administration). The analysis of collected data, calculated using a t test, revealed that the PDA group answered the six questions with greater accuracy and speed than did the textbook group.
Current Perspectives on Pathobiology of the Ductus Arteriosus
Stoller, Jason Z.; DeMauro, Sara B.; Dagle, John M.; Reese, Jeff
2012-01-01
The ductus arteriosus (DA) shunts blood away from the lungs during fetal life, but at birth this shunt is no longer needed and the vessel rapidly constricts. Postnatal persistence of the DA, patent ductus arteriosus (PDA), is predominantly a detrimental condition for preterm infants but is simultaneously a condition required to maintain systemic blood flow for infants born with certain severe congenital heart defects. Although PDA in preterm infants is associated with significant morbidities, there is controversy regarding whether PDA is truly causative. Despite advances in our understanding of the pathobiology of PDA, the optimal treatment strategy for PDA in preterm infants is unclear. Here we review recent studies that have continued to elucidate the fundamental mechanisms of DA development and pathogenesis. PMID:23519783
Polydiacetylene sensor interaction with food sanitizers and surfactants.
Zhang, Yueyuan; Northcutt, Julie; Hanks, Tim; Miller, Ian; Pennington, Bill; Jelinek, Raz; Han, Inyee; Dawson, Paul
2017-04-15
Polydiacetylene (PDA) vesicles are of interest as biosensors, particularly for pathogenic bacteria. As part of a food monitoring system, interaction with food sanitizers/surfactants was investigated. PDA vesicles were prepared by inkjet-printing, photopolymerized and characterized by dynamic light scattering (DLS) and UV/Vis spectroscopy. The optical response of PDA vesicles at various concentrations verses a fixed sanitizer/surfactant concentration was determined using a two variable factorial design. Sanitizer/surfactant response at various concentrations over time was also measured. Results indicated that only Vigilquat and TritonX-100 interacted with PDA vesicles giving visible colour change out of 8 sanitizers/surfactants tested. PDA vesicle concentration, sanitizer/surfactant concentration, and time all had a significant (P<0.0001) effect on colour change. As they are highly sensitive to the presence of Vigilquat and TritonX-100, PDA sensors could be used to detect chemical residues as well as for detection of various contaminants in the food industry. Copyright © 2016. Published by Elsevier Ltd.
Pereira, Catarina Guerreiro; Barreira, Luísa; Bijttebier, Sebastiaan; Pieters, Luc; Neves, Vanessa; Rodrigues, Maria João; Rivas, Ricardo; Varela, João; Custódio, Luísa
2017-10-25
Several medicinal plants are currently used by the food industry as functional additives, for example botanical extracts in herbal drinks. Moreover, the scientific community has recently begun focusing on halophytes as sources of functional beverages. Helichrysum italicum subsp. picardii (everlasting) is an aromatic halophyte common in southern Europe frequently used as spice and in traditional medicine. In this context, this work explored for the first time H. italicum subsp. picardii as a potential source of innovative herbal beverages with potential health promoting properties. For that purpose, infusions and decoctions were prepared from roots, vegetative aerial-organs (stems and leaves) and flowers and evaluated for in vitro antioxidant and anti-diabetic activities. Samples were also assessed for toxicity in different mammalian cell lines and chemically characterized by spectrophotometric methods and ultra-high performance liquid chromatography-photodiode array-mass-spectrometry (UHPLC-PDA-MS). Results were expressed relating to 'a cup-of-tea' and compared with those obtained with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis). Tisanes from the everlasting's above-ground organs, particularly flowers, have high polyphenolic content and several phenolics were identified; the main compounds were chlorogenic and quinic acids, dicaffeoylquinic-acid isomers and gnaphaliin-A. The antioxidant activity of beverages from the everlasting's above-ground organs matched or surpassed that of green tea and rooibos. Its anti-diabetic activity was moderate and toxicity low. Overall, our results suggest that the everlasting is a potential source of innovative and functional herbal beverages. Copyright © 2017 Elsevier B.V. All rights reserved.
House officer procedure documentation using a personal digital assistant: a longitudinal study
Bird, Steven B; Lane, David R
2006-01-01
Background Personal Digital Assistants (PDAs) have been integrated into daily practice for many emergency physicians and house officers. Few objective data exist that quantify the effect of PDAs on documentation. The objective of this study was to determine whether use of a PDA would improve emergency medicine house officer documentation of procedures and patient resuscitations. Methods Twelve first-year Emergency Medicine (EM) residents were provided a Palm V (Palm, Inc., Santa Clara, California, USA) PDA. A customizable patient procedure and encounter program was constructed and loaded into each PDA. Residents were instructed to enter information on patients who had any of 20 procedures performed, were deemed clinically unstable, or on whom follow-up was obtained. These data were downloaded to the residency coordinator's desktop computer on a weekly basis for 36 months. The mean number of procedures and encounters performed per resident over a three year period were then compared with those of 12 historical controls from a previous residency class that had recorded the same information using a handwritten card system for 36 months. Means of both groups were compared a two-tailed Student's t test with a Bonferroni correction for multiple comparisons. One hundred randomly selected entries from both the PDA and handwritten groups were reviewed for completeness. Another group of 11 residents who had used both handwritten and PDA procedure logs for one year each were asked to complete a questionnaire regarding their satisfaction with the PDA system. Results Mean documentation of three procedures significantly increased in the PDA vs handwritten groups: conscious sedation 24.0 vs 0.03 (p = 0.001); thoracentesis 3.0 vs 0.0 (p = 0.001); and ED ultrasound 24.5 vs. 0.0 (p = 0.001). In the handwritten cohort, only the number of cardioversions/defibrillations (26.5 vs 11.5) was statistically increased (p = 0.001). Of the PDA entries, 100% were entered completely, compared to only 91% of the handwritten group, including 4% that were illegible. 10 of 11 questioned residents preferred the PDA procedure log to a handwritten log (mean ± SD Likert-scale score of 1.6 ± 0.9). Conclusion Overall use of a PDA did not significantly change EM resident procedure or patient resuscitation documentation when used over a three-year period. Statistically significant differences between the handwritten and PDA groups likely represent alterations in the standard of ED care over time. Residents overwhelmingly preferred the PDA procedure log to a handwritten log and more entries are complete using the PDA. These favorable comparisons and the numerous other uses of PDAs may make them an attractive alternative for resident documentation. PMID:16438709
Mwakasungula, Solomon; Schindler, Tobias; Jongo, Said; Moreno, Elena; Kamaka, Kasimu; Mohammed, Mgeni; Joseph, Selina; Rashid, Ramla; Athuman, Thabit; Tumbo, Anneth Mwasi; Hamad, Ali; Lweno, Omar; Tanner, Marcel; Shekalaghe, Seif; Daubenberger, Claudia A
2014-01-01
Hemoglobinopathies, disorders of hemoglobin structure and production, are one of the most common monogenic disorders in humans. Glucose 6 phosphate dehydrogenase deficiency (G6PD) is an inherited enzymopathy resulting in increased oxygen stress susceptibility of red blood cells. The distributions of these genetic traits in populations living in tropical and subtropical regions where malaria has been or is still present are thought to result from survival advantage against severe life threatening malaria disease. 384 male Tanzanian volunteers residing in Dar es Salaam were typed for G6PD, sickle cell disease and α-thalassemia. The most prominent red blood cell polymorphism was heterozygous α(+)-thalassemia (37.8%), followed by the G6PD(A) deficiency (16.4%), heterozygous sickle cell trait (15.9%), G6PD(A-) deficiency (13.5%) and homozygous α(+)-thalassemia (5.2%). 35%, 45%, 17% and 3% of these volunteers were carriers of wild type gene loci, one, two or three of these hemoglobinopathies, respectively. We find that using a cut off value of 28.6 pg. for mean corpuscular hemoglobin (MCH), heterozygous α(+)-thalassemia can be predicted with a sensitivity of 84% and specificity of 72% in this male population. All subjects carrying homozygous α(+)-thalassemia were identified based on their MCH value < 28.6 pg.
Wang, Rongyu; Ma, Hongmin; Zhang, Yong; Wang, Qi; Yang, Zhongping; Du, Bin; Wu, Dan; Wei, Qin
2017-10-15
An ultrasensitive photoelectrochemical sandwich immunosensor was designed for detection of insulin based on WO 3 /CdS/polydopamine (WO 3 /CdS/PDA) co-sensitized and PDA@carbon nanotubes (PDA@CNT) conjugates for signal amplification. The CdS nanoparticles were first deposited on the WO 3 nanorods via sequential chemical bath deposition to form the WO 3 /CdS structure to enhance photocurrent. Then equipped with PDA to form the WO 3 /CdS/PDA photosensitive structure. The PDA was used not only to reduce the toxicity of CdS but also adsorb insulin primary antibodies (Ab 1 ). Meanwhile, insulin secondary antibodies (Ab 2 ) were decorated by PDA@CNT conjugates for signal amplification and further enhance photocurrent. Different photocurrent intensities were obtained by the photoelectrochemical workstation at applied bias of 0V due to the different amount of the PDA@CNT conjugates introduced by the different concentrations of insulin. A good linear relationship was obtained between the increased photocurrent and insulin concentrations range from 0.01ngmL -1 to 50ngmL -1 . And a detection limit of 2.8pgmL -1 was obtained. The proposed sensor was applied to the determination of the insulin in human serum sample, and satisfactory results were obtained. The sensor presented good specificity, reproducibility and stability, thus it might find application in the clinical diagnosis of insulin or other biomarkers in the near future. Copyright © 2017 Elsevier B.V. All rights reserved.
Daemen, Anneleen; Peterson, David; Sahu, Nisebita; McCord, Ron; Du, Xiangnan; Liu, Bonnie; Kowanetz, Katarzyna; Hong, Rebecca; Moffat, John; Gao, Min; Boudreau, Aaron; Mroue, Rana; Corson, Laura; O’Brien, Thomas; Qing, Jing; Sampath, Deepak; Merchant, Mark; Yauch, Robert; Manning, Gerard; Settleman, Jeffrey; Hatzivassiliou, Georgia; Evangelista, Marie
2015-01-01
Although targeting cancer metabolism is a promising therapeutic strategy, clinical success will depend on an accurate diagnostic identification of tumor subtypes with specific metabolic requirements. Through broad metabolite profiling, we successfully identified three highly distinct metabolic subtypes in pancreatic ductal adenocarcinoma (PDAC). One subtype was defined by reduced proliferative capacity, whereas the other two subtypes (glycolytic and lipogenic) showed distinct metabolite levels associated with glycolysis, lipogenesis, and redox pathways, confirmed at the transcriptional level. The glycolytic and lipogenic subtypes showed striking differences in glucose and glutamine utilization, as well as mitochondrial function, and corresponded to differences in cell sensitivity to inhibitors of glycolysis, glutamine metabolism, lipid synthesis, and redox balance. In PDAC clinical samples, the lipogenic subtype associated with the epithelial (classical) subtype, whereas the glycolytic subtype strongly associated with the mesenchymal (QM-PDA) subtype, suggesting functional relevance in disease progression. Pharmacogenomic screening of an additional ∼200 non-PDAC cell lines validated the association between mesenchymal status and metabolic drug response in other tumor indications. Our findings highlight the utility of broad metabolite profiling to predict sensitivity of tumors to a variety of metabolic inhibitors. PMID:26216984
Goswami, Akshra; Shah, Bhahwal Ali; Batra, Navneet; Kumar, Ajay; Guru, Santosh Kumar; Bhushan, Shashi; Malik, Fayaz Ahmad; Joshi, Amit; Singh, Jagtar
2016-01-01
Pancreatic ductal adenocarcinoma (PDA) remains one of the deadliest types of cancers. Median survival rate is very poor with the currently available chemotherapeutical regimens. Therefore, discovery of new antineoplastic agents against PDA is one of the focused areas of contemporary research. The present study was undertaken to explore the antitumour activity of a potent parthenin analog P16. Among PANC-1, Mia PaCa-2 and AsPC-1 pancreatic cancer cells, PANC-1 showed highest sensitivity to P16 with an IC50 value of 3.4 μM. Time dependent cell cycle studies revealed that P16 suppressed the growth of PANC-1 cells by arresting the progression through the cell cycle in G2/M phase via downregulation of cyclin B1 and cyclin A. However, P16 did not alter the expressions of CDK-1 and CDC25C in PANC-1 cells. The P16 induced cell cycle arrest, which consequently, led to induction of apoptosis, which was accompanied by activation of caspase-9 and -3. Interestingly, PANC-1 cells displayed increasing loss of mitochondrial potential, which seemed to be correlated to the activation of caspase-3. Additionally, P16 was also able to down-regulate the cell migration in PANC-1 cells. Furthermore, P16 treatment of hypoxic PANC-1 cells strongly suppressed the expression of proangiogenic factors VEGFR-2, HIF1α and HIF1β. Antiangiogenic ability of P16 was also reflected in the human umbilical vascular endothelial cells (HUVECs), where it effectively suppressed the migration and inhibited the formation of the tube in a matrigel based assay. Therefore, cytostatic and antiangiogenic properties of P16 against pancreatic adenocarcinoma cells make it a suitable candidate for further investigation.
Learning Objects for Educational Applications via PDA Technology
ERIC Educational Resources Information Center
Churchill, Daniel
2008-01-01
This article discusses an ongoing study into issues relevant to the design of learning objects for educational applications via portable digital assistant (PDA) technology. The specific areas of inquiry in this study are: the kinds of learning objects that are effective for PDA delivery; contexts for their effective educational applications; and…
Use of a Stent Graft for Patent Ductus Arteriosus in an Octogenarian Eliminates Ductus Flow.
Tatsuishi, Wataru; Kataoka, Go; Asano, Ryota; Sato, Atsuhiko; Nakano, Kiyoharu
2016-06-20
Closure of a patent ductus arteriosus (PDA) in the elderly is a high-risk procedure because of tissue fragility and many possible complications. The patient in our case was an 81-year-old woman with a window-type PDA caused by cardiac failure. Based on the anatomy of the PDA and aorta and to minimize invasion, we used a stent graft to close the PDA. This approach was successful; hemodynamics improved and ductus flow was eliminated during the follow-up period without intervention from the pulmonary artery side.
Hemodynamic features of congenital aortic valve stenosis with patent ductus arteriosus in children.
Xie, Chunhong; Xia, Chengsen; Zhao, Zhengyan; Zhou, Yinbao
2007-12-01
The aim of the present paper was to investigate the hemodynamic features of congenital aortic valvar stenosis (AS) associated with patent ductus arteriosus (PDA), and to develop information to guide management of AS with coexistent PDA. Hemodynamic measurements were performed in eight of 11 patients with AS before and following transcatheter closure of a PDA. Doppler cardiac ultrasound and chest X-rays were performed during follow up. In each of the 11 patients, aortic valve gradient was markedly reduced following transcatheter ductal closure. In only one of them was balloon aortic valvuloplasty necessary. Aortic valve gradient was markedly overestimated before closure of PDA. The significance of this finding has focused on selecting appropriate management so that a PDA is not overlooked when intervention for AS is performed.
Gomez, Jorge E; Gentile, Jorge I
2011-01-01
Two children were sent to the catheterization laboratory for transcatheter closure of patent ductus arteriosus (PDA). During the intervention, cineangiogram revealed associated aberrant right subclavian artery (ARSA). Both patients had left-sided aortic arch. The first patient was sent to surgery after one unsuccessful attempt to close the PDA due to the proximity of the ARSA and also because of other concomitant cardiac lesions. We successfully treated the second patient by closing the PDA with a Nit-Occlud® PDA occlusion device (Pfm Medical, Carlsbad, California). Similar mirror cases of PDA closure with aberrant left subclavian artery and right aortic arch have been reported. Anatomic features, as well as the technique and management of the procedure, are discussed here.
Yin, Tiansheng; Wan, Zhili; Chen, Hongwei; Mao, Xixian; Yi, Yayang; Li, Dewei
2015-07-01
Pancreaticoduodenal artery aneurysm (PDA) is quite rare, which accounts for only approximate 2% of all visceral aneurysms. Besides, PDA is usually related to celiac axis stenosis (CAS) and prone to rupture. Advanced imaging examination can facilitate the disclosure of such peripancreatic masses, but most of them were seldom diagnosed until they rupture because of the nonspecific symptoms. Secondary to PDA, obstructive jaundice is however an extremely rare manifestation. A case of an 84-year-old man is reported here, who suffered from severe jaundice caused by a ruptured PDA associated with CAS. In addition, this review collects and organizes PDAs with jaundice by applying a MEDLINE search and discusses the pathogenesis and therapeutic options of these aneurysms leading to external compression over the bile duct. Consequently, the formation of PDA with obstructive jaundice is based on the specific anatomy of pancreaticoduodenal arcades. When there is a retroperitoneal mass around the head of the pancreas associated with unexpected jaundice, PDA should be considered, for which early aggressive therapy is required. The case report and literature review suggest that PDA associated with obstructive jaundice may be treated successfully by single transcatheter arterial embolization (TAE) without auxiliary biliary drainage, whether it ruptures or not. Copyright © 2015 Elsevier Inc. All rights reserved.
Forsell, M; Häggström, M; Johansson, O; Sjögren, P
2008-11-08
To develop a personal digital assistant (PDA) application for oral health assessment fieldwork, including back-office and database systems (MobilDent). System design, construction and implementation of PDA, back-office and database systems. System requirements for MobilDent were collected, analysed and translated into system functions. User interfaces were implemented and system architecture was outlined. MobilDent was based on a platform with. NET (Microsoft) components, using an SQL Server 2005 (Microsoft) for data storage with Windows Mobile (Microsoft) operating system. The PDA devices were Dell Axim. System functions and user interfaces were specified for MobilDent. User interfaces for PDA, back-office and database systems were based on. NET programming. The PDA user interface was based on Windows suitable to a PDA display, whereas the back-office interface was designed for a normal-sized computer screen. A synchronisation module (MS Active Sync, Microsoft) was used to enable download of field data from PDA to the database. MobilDent is a feasible application for oral health assessment fieldwork, and the oral health assessment database may prove a valuable source for care planning, educational and research purposes. Further development of the MobilDent system will include wireless connectivity with download-on-demand technology.
TFAP2B mutation and dental anomalies.
Tanasubsinn, Natchaya; Sittiwangkul, Rekwan; Pongprot, Yupada; Kawasaki, Katsushige; Ohazama, Atsushi; Sastraruji, Thanapat; Kaewgahya, Massupa; Kantaputra, Piranit Nik
2017-08-01
Mutations inTFAP2B has been reported in patients with isolated patent ductus arteriosus (PDA) and Char syndrome. We performed mutation analysis of TFAP2B in 43 patients with isolated PDA, 7 patients with PDA with other congenital heart defects and 286 patients with isolated tooth agenesis with or without other dental anomalies. The heterozygous c.1006G>A mutation was identified in 20 individuals. Those mutation carriers consisted of 1 patient with term PDA (1/43), 16 patients with isolated tooth agenesis with or without other dental anomalies (16/286; 5.6%), 1 patient with PDA and severe valvular aortic stenosis and tooth agenesis (1/4) and 2 normal controls (2/100; 1%). The mutation is predicted to cause an amino-acid substitution p.Val336Ile in the TFAP2B protein. Tfap2b expression during early mouse tooth development supports the association of TFAP2B mutation and dental anomalies. It is hypothesized that this incidence might have been the result of founder effect. Here we report for the first time that TFAP2B mutation is associated with tooth agenesis, microdontia, supernumerary tooth and root maldevelopment. In addition, we also found that TFAP2B mutations, the common causes of PDA in Caucasian, are not the common cause of PDA in Thai population.
Patent Ductus Arteriosus in Preterm Infants: Do We Have the Right Answers?
Nasef, Nehad; Nour, Islam
2013-01-01
Patent ductus arteriosus (PDA) is a common clinical condition in preterm infants. Preterm newborns with PDA are at greater risk for several morbidities, including higher rates of bronchopulmonary dysplasia (BPD), decreased perfusion of vital organs, and mortality. Therefore, cyclooxygenase (COX) inhibitors and surgical interventions for ligation of PDA are widely used. However, these interventions were reported to be associated with side effects. In the absence of clear restricted rules for application of these interventions, different strategies are adopted by neonatologists. Three different approaches have been investigated including prophylactic treatment shortly after birth irrespective of the state of PDA, presymptomatic treatment using echocardiography at variable postnatal ages to select infants for treatment prior to the duct becoming clinically significant, and symptomatic treatment once PDA becomes clinically apparent or hemodynamically significant. Future appropriately designed randomized controlled trials (RCTs) to refine selection of patients for medical and surgical treatments should be conducted. Waiting for new evidence, it seems wise to employ available clinical and echocardiographic parameters of a hemodynamically significant (HS) PDA to select patients who are candidates for medical treatment. Surgical ligation of PDA could be used as a back-up tool for those patients who failed medical treatment and continued to have hemodynamic compromise. PMID:24455715
Cardiac remodeling in preterm infants with prolonged exposure to a patent ductus arteriosus.
de Waal, Koert; Phad, Nilkant; Collins, Nick; Boyle, Andrew
2017-05-01
Sustained volume load due to a patent ductus arteriosus (PDA) leads to cardiac remodeling. Remodeling changes can become pathological and are associated with cardiovascular disease progression. Data on remodeling changes in preterm infants is not available. Clinical and echocardiography data were collected in preterm infants <30 weeks gestation on postnatal day 3 and then every 7-14 days until closure of the ductus arteriosus. Images were analyzed using conventional techniques and speckle tracking. Remodeling changes of infants with prolonged (>14 days) exposure to a PDA were compared to control infants without a PDA. Thirty out of 189 infants had prolonged exposure to a PDA. The left heart remodeled to a larger and more spherical shape and thus significantly increased in volume. Most changes occurred in the first 4 weeks, plateaued, and then returned to control values. Systolic function and estimates of filling pressure increased and effective arterial elastance reduced with a PDA, however contractility was unchanged. Wall thickness increased after 4 weeks of increased volume exposure. The preterm PDA induces early and significant remodeling of the left heart. A compensated cardiac physiology was seen with preserved systolic function, suggesting adaptive rather than pathological remodeling changes with prolonged exposure to a PDA. © 2017 Wiley Periodicals, Inc.
Relationship between perfusion index and patent ductus arteriosus in preterm infants.
Gomez-Pomar, Enrique; Makhoul, Majd; Westgate, Philip M; Ibonia, Katrina T; Patwardhan, Abhijit; Giannone, Peter J; Bada, Henrietta S; Abu Jawdeh, Elie G
2017-05-01
Perfusion index (PI) is a noninvasive measure of perfusion. ΔPI (difference between pre- and postductal PI) may identify hemodynamically significant PDA. However, studies are limited to brief and intermittent ΔPI sampling. Our objective is to assess the value of continuous high resolution ΔPI monitoring in the diagnosis of PDA. Continuous ΔPI monitoring in preterm infants was prospectively performed using two high-resolution pulse oximeters. Perfusion Index measures (ΔPI mean and variability, pre- and postductal PI) were analyzed over a 4-h period prior to echocardiography. A cardiologist blinded to the results evaluated for PDA on echocardiography. Linear mixed regression models were utilized for analyses. We obtained 31 echocardiography observations. Mean ΔPI (-0.23 vs. 0.16; P < 0.05), mean pre-PI (0.86 vs. 1.26; P < 0.05), and ΔPI variability (0.39 vs. 0.61; P = 0.05) were lower in infants with PDA compared to infants without PDA at the time of echocardiography. Mean ΔPI, ΔPI variability, and mean pre-PI measured 4 h prior to echocardiography detect PDA in preterm infants. PI is dynamic and should be assessed continuously. Perfusion index is a promising bedside measurement to identify PDA in preterm infants.
Feng, Junran; Fan, Hailong; Zha, Dao-An; Wang, Le; Jin, Zhaoxia
2016-10-11
Recent studies demonstrated that polydopamine (PDA) coating is universal to nearly all substrates, and it endows substrates with biocompatibility, postfunctionality, and other useful properties. Surface chemistry of PDA coating is important for its postmodifications and applications. However, there is less understanding of the formation mechanism and surface functional groups of PDA layers generated in different conditions. Halloysite is a kind of clay mineral with tubular nanostructure. Water-swellable halloysite has unique reactivity. In this study, we have investigated the reaction of dopamine in the presence of water-swellable halloysite. We have tracked the reaction progresses in different pH environments by using UV-vis spectroscopy and surface-enhanced Raman spectroscopy (SERS). The surface properties of PDA on halloysite were clarified by X-ray photoelectron spectroscopy (XPS), SERS, Fourier transform infrared (FTIR) characterizations, zeta potential, surface wettability, and morphological characterizations. We noticed that the interaction between halloysite surface and dopamine strongly influences the surface functionality of coated PDA. In addition, pH condition further modulates surface functional groups, resulting in less content of secondary/aromatic amine in PDA generated in weak acidic environment. This study demonstrates that the formation mechanism of polydopamine becomes complex in the presence of inorganic nanomaterials. Substrate property and reaction condition dominate the functionality of obtained PDA together.
Liang, Jiajie; Huang, Lu; Li, Na; Huang, Yi; Wu, Yingpeng; Fang, Shaoli; Oh, Jiyoung; Kozlov, Mikhail; Ma, Yanfeng; Li, Feifei; Baughman, Ray; Chen, Yongsheng
2012-05-22
Although widely investigated, novel electromechanical actuators with high overall actuation performance are still in urgent need for various practical and scientific applications, such as robots, prosthetic devices, sensor switches, and sonar projectors. In this work, combining the properties of unique environmental perturbations-actuated deformational isomerization of polydiacetylene (PDA) and the outstanding intrinsic features of graphene together for the first time, we design and fabricate an electromechanical bimorph actuator composed of a layer of PDA crystal and a layer of flexible graphene paper through a simple yet versatile solution approach. Under low applied direct current (dc), the graphene-PDA bimorph actuator with strong mechanical strength can generate large actuation motion (curvature is about 0.37 cm(-1) under a current density of 0.74 A/mm(2)) and produce high actuation stress (more than 160 MPa/g under an applied dc of only 0.29 A/mm(2)). When applying alternating current (ac), this actuator can display reversible swing behavior with long cycle life under high frequencies even up to 200 Hz; significantly, while the frequency and the value of applied ac and the state of the actuators reach an appropriate value, the graphene-PDA actuator can produce a strong resonance and the swing amplitude will jump to a peak value. Moreover, this stable graphene-PDA actuator also demonstrates rapidly and partially reversible electrochromatic phenomenon when applying an ac. Two mechanisms-the dominant one, electric-induced deformation, and a secondary one, thermal-induced expansion of PDA-are proposed to contribute to these interesting actuation performances of the graphene-PDA actuators. On the basis of these results, a mini-robot with controllable direction of motion based on the graphene-PDA actuator is designed to illustrate the great potential of our discoveries for practical use. Combining the unique actuation mechanism and many outstanding properties of graphene and PDA, this novel kind of graphene-PDA actuator exhibits compelling advantages to traditional electromechanical actuation technology and may provide a new avenue for actuation applications.
Tong, Wen Ting; Lee, Yew Kong; Ng, Chirk Jenn; Lee, Ping Yein
2017-03-21
Most studies on barriers and facilitators to implementation of patient decision aids (PDAs) are conducted in the west; hence, the findings may not be transferable to developing countries. This study aims to use a locally developed insulin PDA as an exemplar to explore the barriers and facilitators to implementing PDAs in Malaysia, an upper middle-income country in Asia. Qualitative methodology was adopted. Nine in-depth interviews (IDIs) and three focus group discussions (FGDs) were conducted with policymakers (n = 6), medical officers (n = 13), diabetes educators (n = 5) and a nurse, who were involved in insulin initiation management at an academic primary care clinic. The interviews were conducted with the aid of a semi-structured interview guide based on the Theoretical Domains Framework. The interviews were audio-recorded, transcribed verbatim and analyzed using a thematic approach. Five themes emerged, and they were lack of shared decision-making (SDM) culture, role boundary, lack of continuity of care, impact on consultation time and reminder network. Healthcare providers' (HCPs) paternalistic attitude, patients' passivity and patient trust in physicians rendered SDM challenging which affected the implementation of the PDA. Clear role boundaries between the doctors and nurses made collaborative implementation of the PDA challenging, as nurses may not view the use of insulin PDA to be part of their job scope. The lack of continuity of care might cause difficulties for doctors to follow up on insulin PDA use with their patient. While time was the most commonly cited barrier for PDA implementation, use of the PDA might reduce consultation time. A reminder network was suggested to address the issue of forgetfulness as well as to trigger interest in using the PDA. The suggested reminders were peer reminders (i.e. HCPs reminding one another to use the PDA) and system reminders (e.g. incorporating electronic medical record prompts, displaying posters/notices, making the insulin PDA available and visible in the consultation rooms). When implementing PDAs, it is crucial to consider the healthcare culture and system, particularly in developing countries such as Malaysia where concepts of SDM and PDAs are still novel.
Agha, Hala Mounir; Hamza, Hala S; Kotby, Alyaa; Ganzoury, Mona E L; Soliman, Nanies
2017-10-01
To evaluate the left ventricular function before and after transcatheter percutaneous patent ductus arteriosus (PDA) closure, and to identify the predictors of myocardial dysfunction post-PDA closure if present. Transcatheter PDA closure; conventional, Doppler, and tissue Doppler imaging; and speckle tracking echocardiography. To determine the feasibility and reliability of tissue Doppler and myocardial deformation imaging for evaluating myocardial function in children undergoing transcatheter PDA closure. Forty-two children diagnosed with hemodynamically significant PDA underwent percutaneous PDA closure. Conventional, Doppler, and tissue Doppler imaging, and speckle-derived strain rate echocardiography were performed at preclosure and at 48 hours, 1 month, and 6 months postclosure. Tissue Doppler velocities of the lateral and septal mitral valve annuli were obtained. Global and regional longitudinal peak systolic strain values were determined using two-dimensional speckle tracking echocardiography. The median age of the patients was 2 years and body weight was 15 kg, with the mean PDA diameter of 3.11 ± 0.99 mm. M-mode measurements (left ventricular end diastolic diameter, left atrium diameter to aortic annulus ratio, ejection fraction, and shortening fraction) reduced significantly early after PDA closure ( p < 0.001). After 1 month, left ventricular end diastolic diameter and left atrium diameter to aortic annulus ratio continued to decrease, while ejection fraction and fractional shortening improved significantly. All tissue Doppler velocities showed a significant decrease at 48 hours with significant prolongation of global myocardial function ( p < 0.001) and then were normalized within 1 month postclosure. Similarly, global longitudinal strain significantly decreased at 48 hours postclosure ( p < 0.001), which also recovered at 1 month follow-up. Preclosure global longitudinal strain showed a good correlation with the postclosure prolongation of the myocardial performance index. Transcatheter PDA closure causes a significant decrease in left ventricular performance early after PDA closure, which recovers completely within 1 month. Preclosure global longitudinal strain can be a predictor of postclosure myocardial dysfunction.
Jiang, Jiebing; Sun, Xueni; Li, Yan; Deng, Chunhui; Duan, Gengli
2018-02-01
Metal ions differed greatly in affinity towards phosphopeptides, and thus it is essential to systematically compare the phosphopeptides enrichment ability of different metal ions usually used in the IMAC techniques. In this work, for the first time, eight metal ions, including Nb 5+ , Ti 4+ , Zr 4+ , Ga 3+ , Y 3+ , In 3+ , Ce 4+ , Fe 3+ , were immobilized on the polydopamine (PDA)-coated Fe 3 O 4 (denoted as Fe 3 O 4 @PDA-M n+ ), and systematically compared by the real biosamples, in addition to standard phosphopeptides. Fe 3 O 4 microspheres were synthesized via the solvothermal reaction, followed by self-polymerization of dopamine on the surface. Then through taking advantage of the hydroxyl and amino group of PDA, the eight metal ions were easily adhered to the surface of Fe 3 O 4 @PDA. After characterization, the resultant Fe 3 O 4 @PDA-M n+ microspheres were applied to phosphopeptides enrichment based on the binding affinity between metal ions and phosphopeptides. According to the results, different metal ions presented diverse phosphopeptides enrichment efficiency in terms of selectivity, sensitivity and the enrichment ability from real complex samples, and Fe 3 O 4 @PDA-Nb 5+ and Fe 3 O 4 @PDA-Ti 4+ showed obvious advantages of the phosphopeptides enrichment effect after the comparison. This systematic comparison may provide certain reference for the use and development of IMAC materials in the future. Copyright © 2017 Elsevier B.V. All rights reserved.
Djer, Mulyadi M; Saputro, Dimas Dwi; Putra, Sukman Tulus; Idris, Nikmah Salamia
2015-06-01
Transcatheter closure of patent ductus arteriosus (PDA) has been suggested to be the standard treatment of PDA. Although, in general, the procedure shows a high successful rate, outcomes may vary among pediatric cardiology centers. To evaluate the effectiveness of transcatheter closure of PDA in Cipto Mangunkusumo Hospital, Jakarta, Indonesia, this was a retrospective study on patients who underwent transcatheter closure of PDA in Cipto Mangunkusumo Hospital during the period of 2002-2013. Hospital registry was reviewed and data about patients' characteristics, PDA severity, procedure, and outcomes were retrieved. There were 298 patients, of whom 90 were males, who underwent transcatheter closure of PDA during the study period. Median age was 3.4 years (1 months-18 years), and median body weight was 12 (3.6-59) kg. The diameter of PDA ranged from 1.1 to 15.4 mm with a median of 3.7 mm. Device could be deployed in all patients, in which most were the Amplatzer ductal occluder (69.8 %) and the remainders were coils. Median fluoroscopy time was 15.4 (1.5-87) min, and procedure time was 76 (30-200) min. Complete closure was achieved in most patients (97.3 %), whereas device migration occurred in a minority (0.3 %) of patients. No major complication occurred during or after the procedure. Transient anemia and bradycardia were found in 3.7 and 1.3 % patients, respectively. Most patients were discharged from the hospital at 1 day after the procedure. Transcatheter closure method is a safe and effective procedure to close PDA.
Thrombocytopenia in the first 24 hours after birth and incidence of patent ductus arteriosus.
Sallmon, Hannes; Weber, Sven C; Hüning, Britta; Stein, Anja; Horn, Peter A; Metze, Boris C; Dame, Christof; Bührer, Christoph; Felderhoff-Müser, Ursula; Hansmann, Georg; Koehne, Petra
2012-09-01
Experimental studies suggest that platelet-triggered ductal sealing is critically involved in definite ductus arteriosus closure. Whether thrombocytopenia contributes to persistently patent ductus arteriosus (PDA) in humans is controversial. This was a retrospective study of 1350 very low birth weight (VLBW; <1500 g) infants, including 592 extremely low birth weight (ELBW; <1000 g) infants. All infants who had a platelet count in the first 24 hours after birth and an echocardiogram performed on day of life 4 to 5 were included. The incidence of thrombocytopenia was analyzed in infants with and without PDA, and in those who did or did not undergo PDA intervention. The impact of thrombocytopenia, gestational age, birth weight, gender, and sepsis on PDA was determined by receiver operating characteristic curve, odds ratio, and regression analyses. Platelet numbers within the first 24 hours after birth did not differ between VLBW/ELBW infants with and without spontaneous ductal closure. Platelet numbers were not associated with subsequent PDA treatment. Low platelet counts were not related to failure of pharma-cologic PDA treatment and the need for subsequent surgical ligation. Lower gestational age or birth weight, male gender, and sepsis were linked to the presence of PDA in VLBW infants on day of life 4 to 5. Thrombocytopenia in the first 24 hours after birth was not associated with PDA in this largest VLBW/ELBW infant cohort studied to date. Impaired platelet function, due to immaturity and critical illness, rather than platelet number, might play a role in ductus arteriosus patency.
McGuirl, Jennifer; Arzuaga, Bonnie; Lee, Ben H
2012-01-01
This study aimed to assess whether tocolytic fetal exposure to antenatal calcium channel blockers (aCCB) increases the risk for hemodynamically significant patent ductus arteriosus (hsPDA) in extremely low-birth-weight (ELBW) infants. This case-control study investigated ELBW infants (<1,000 g) without cardiac defects in a level 3 neonatal intensive care unit who had survived at least 7 days. Nifedipine was the only aCCB used for this study population. The measurements included the history of aCCB exposure, selected maternal data, hsPDA diagnosis, gestational age at birth, birth weight, mode of delivery, sex, maternal race, location of birth, Apgar scores, and selected neonatal morbidities. The end point of the study was hsPDA, defined as an echocardiographically confirmed PDA with clinical symptoms. A total of 180 infants met the study criteria. The diagnosis was hsPDA for 56% of these patients, 20% of whom had aCCB exposure. Of the infants without hsPDA, 11% had aCCB exposure (p = 0.09). No statistically significant associations were found between aCCB exposure and hsPDA after adjustment for gestational age (odds ratio [OR], 1.5; 95% confidence interval [CI], 0.6-3.7) or for gestational age and cumulative aCCB exposure of 100 mg or more (OR, 2.0; 95% CI, 0.6-6.5). A history of aCCB exposure does not appear to increase hsPDA risk in ELBW infants. Studies using neonatal serum nifedipine concentrations after antenatal exposure should be performed to confirm this conclusion.
Network of wireless gamma ray sensors for radiological detection and identification
NASA Astrophysics Data System (ADS)
Barzilov, A.; Womble, P.; Novikov, I.; Paschal, J.; Board, J.; Moss, K.
2007-04-01
The paper describes the design and development of a network of wireless gamma-ray sensors based on cell phone or WiFi technology. The system is intended for gamma-ray detection and automatic identification of radioactive isotopes and nuclear materials. The sensor is a gamma-ray spectrometer that uses wireless technology to distribute the results. A small-size sensor module contains a scintillation detector along with a small size data acquisition system, PDA, battery, and WiFi radio or a cell phone modem. The PDA with data acquisition and analysis software analyzes the accumulated spectrum on real-time basis and returns results to the screen reporting the isotopic composition and intensity of detected radiation source. The system has been programmed to mitigate false alarms from medical isotopes and naturally occurring radioactive materials. The decision-making software can be "trained" to indicate specific signatures of radiation sources like special nuclear materials. The sensor is supplied with GPS tracker coupling radiological information with geographical coordinates. The sensor is designed for easy use and rapid deployment in common wireless networks.
40 CFR 799.3300 - Unsubstituted phenylenediamines.
Code of Federal Regulations, 2011 CFR
2011-07-01
... proves to be unstable under the conditions of this study. Either the hydrochloride or sulfate salt of o-pda, p-pda, or m-pda shall be used as a test substance in the 90-day subchronic neurotoxicity studies... these studies. The salt(s) shall be of at least 98 percent purity. (b) Persons required to submit study...
Hu, Dehong; Zhang, Jingnan; Gao, Guanhui; Sheng, Zonghai; Cui, Haodong; Cai, Lintao
2016-01-01
Photoacoustic (PA) imaging and photothermal therapy (PTT) as light-induced theranostic platforms have been attracted much attention in recent years. However, the development of highly efficient and integrated phototheranostic nanoagents for amplifying PA imaging and PTT treatments poses great challenges. Here, we report a novel phototheranostic nanoagent using indocyanine green-loaded polydopamine-reduced graphene oxide nanocomposites (ICG-PDA-rGO) with amplifying PA and PTT effects for cancer theranostics. The results demonstrate that the PDA layer coating on the surface of rGO could effectively absorb a large number of ICG molecules, quench ICG's fluorescence, and enhance the PDA-rGO's optical absorption at 780 nm. The obtained ICG-PDA-rGO exhibits stronger PTT effect and higher PA contrast than that of pure GO and PDA-rGO. After PA imaging-guided PTT treatments, the tumors in 4T1 breast subcutaneous and orthotopic mice models are suppressed completely and no treatment-induced toxicity being observed. It illustrates that the ICG-PDA-rGO nanocomposites constitute a new class of theranostic nanomedicine for amplifying PA imaging and PTT treatments.
Characterization of Polydopamine-Coated Polyethersulfone (PES) membrane for water purification
NASA Astrophysics Data System (ADS)
Syawaliah; Mulyati, S.; Muzaitun; Mulyasari, R.
2018-05-01
The polyethersulfone (PES) membrane has been prepared by phase inversion method using N-methyl-2-pyrolidone (NMP) as solvent and polydopamine (PDA) as additive. The fabricated membrane was modified by coating with PDA of 0.5 g/l concentration and 180 minutes immersion time. The characteristic of the PES membranes before and after the modification was studied in this paper. The result of the pure water permeation experiment showed that the PDA-coated PES membrane showcased a higher flux than that of pure PES membrane. Scanning Electron Microscopy (SEM) analysis confirmed that the membrane had an asymmetric structure consisting of two layers. There was no significant influence on the addition of PDA to the morphology of the pore matrix because the modification was done by surface coating. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that PDA was successfully introduced on the surface of PES membrane with the appearance of peak O-H from catechol at wavenumber of 3348 cm-1. Modification with PDA increased the mechanical strength of the membrane which affirmed by the results of the tensile and elongation at break evaluation.
Histological evaluation of obliterative phlebitis for the diagnosis of autoimmune pancreatitis.
Miyabe, Katsuyuki; Notohara, Kenji; Nakazawa, Takahiro; Hayashi, Kazuki; Naitoh, Itaru; Okumura, Fumihiro; Shimizu, Shuya; Yoshida, Michihiro; Yamashita, Hiroaki; Takahashi, Satoru; Ohara, Hirotaka; Joh, Takashi
2014-04-01
Obliterative phlebitis is a useful pathological finding for the diagnosis of lymphoplasmacytic sclerosing pancreatitis (LPSP), or type 1 autoimmune pancreatitis. The present study evaluated histological findings of obliterative phlebitis, including the significance of adding Elastica van Gieson stain (EVG) in comparison with other pancreatic conditions. Specimens of LPSP (n = 18), chronic pancreatitis (CP; n = 24), and pancreatic ductal adenocarcinoma (PDA; n = 45) were enrolled. Obliterative venous lesions (OVLs), defined as the presence of inflammatory cells and/or fibrosis inside the tunica adventitia, were counted and compared between hematoxylin and eosin stain (H&E) and EVG. OVLs were classified into three types: OVL-1, lymphoplasmacytic infiltration and fibrosis against a loose textured background; OVL-2, dense fibrosis with minimal or no lymphoplasmacytic infiltration; and OVL-3, densely packed lymphoplasmacytic infiltration without fibrosis. OVL type and OVL size were compared between disease groups. OVL counts in LPSP, CP, and PDA were significantly higher with EVG than with H&E (p < 0.001). OVL-1 was most common in LPSP (H&E 92.4 %, EVG 79.8 %), and was identified in almost all cases of LPSP, but was less common in CP and PDA. Maximum diameter and OVL count in 1 cm(2) of OVL-1 were high for LPSP. Maximum diameter of OVL-1 ≥150 μm was observed in 17 LPSP, 0 CP, and 1 PDA cases (sensitivity 94.4 %, specificity 98.6 %). Additional EVG is useful for excluding conditions mimicking OVL-1 or detecting OVL in small specimens. The presence of OVL-1 with diameter ≥150 μm is highly diagnostic for LPSP.
Chang, Polun; Tzeng, Yuann-Meei; Wu, Shiao-Chi; Sang, Ying-Yang; Chen, Shih-Shin
2003-01-01
An advanced PDA support system for the triage was designed to evaluate users inverted exclamation mark | acceptance of this system compared with a traditional terminal system. Davis inverted exclamation mark | Technology Acceptance Model was used to evaluate users inverted exclamation mark | acceptance. All 72 ER nurses in a 2700-bed medical center were invited for the study. The results showed that the PDA system was easier to operate than the terminal one, but had worse interface. The subjects showed significantly greater willingness to accept the terminal system instead of the PDA system. The comparative acceptance of PDA, compared with that of the old system, might still be marginally too low if its interface couldn inverted exclamation mark |t be improved or no other unique practical benefits could be verified.
Hou, Jie; Guo, Chunlei; Shi, Yuzhi; Liu, Ergang; Dong, Weibing; Yu, Bo; Liu, Shiyuan; Gong, Junbo
2017-11-25
A novel high drug loading pH-cleavable polymer hybrid nanoparticle was prepared via doxorubicin (DOX) grafted onto PEGylated, mussel-inspired polydopamine (PDA) and then coated onto hollow silica nanoparticles for drug delivery. A series of characterization shed light on the formation mechanisms of PDA coatings on hollow silica. We hypothesized that dopamine was first absorbed onto the surface of hollow silica and then began self-polymerization. A Dox-containing thiol moiety was fabricated with conjugation between doxorubicin hydrochloride and Mercaptopropionyalkali with a pH-cleavable hydrozone bond. Using a Michael addition reaction, several Dox-containing thiol moieties were grafted onto the surface of the PDA. The drug loading capacity can reach 35.43%. It can minimize the metabolic problem of silica. The released behavior of Dox can be significantly enhanced at endosomal pH compared to physiological pH. After folate modification, nanoparticles can lead to more cellular endocytosis. Meanwhile animal assays showed that more Dox accumulated in tumor tissue, which can enhanced the cytotoxicity to 4T1 cancer cells with a targeting group compared to free DOX and untargeted groups. Meanwhile, the tumor growth was significantly inhibited. This promising material shows a promising future as a drug delivery system. Copyright © 2017 Elsevier B.V. All rights reserved.
Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie
2016-01-01
A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl−/SO42− separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl−/SO42− permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later. PMID:27853255
Fbxw7 Deletion Accelerates KrasG12D-Driven Pancreatic Tumorigenesis via Yap Accumulation.
Zhang, Qiang; Zhang, Yaqing; Parsels, Joshua D; Lohse, Ines; Lawrence, Theodore S; Pasca di Magliano, Marina; Sun, Yi; Morgan, Meredith A
2016-11-01
Pancreatic cancers driven by KRAS mutations require additional mutations for tumor progression. The tumor suppressor FBXW7 is altered in pancreatic cancers, but its contribution to pancreatic tumorigenesis is unknown. To determine potential cooperation between Kras mutation and Fbxw7 inactivation in pancreatic tumorigenesis, we generated P48-Cre;LSL-Kras G12D ;Fbxw7 fl/fl (KFC fl/fl ) compound mice. We found that KFC fl/fl mice displayed accelerated tumorigenesis: all mice succumbed to pancreatic ductal adenocarcinoma (PDA) by 40 days of age, with PDA onset occurring by 2 weeks of age. PDA in KFC fl/fl mice was preceded by earlier onset of acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) lesions, and associated with chromosomal instability and the accumulation of Fbxw7 substrates Yes-associated protein (Yap), c-Myc, and Notch. Using KFC fl/fl and FBXW7-deficient human pancreatic cancer cells, we found that Yap silencing attenuated growth promotion by Fbxw7 deletion. Our data demonstrate that Fbxw7 is a potent suppressor of Kras G12D -induced pancreatic tumorigenesis due, at least in part, to negative regulation of Yap. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie
2016-11-17
A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl - /SO 4 2- separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl - /SO 4 2- permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm 2 30 minutes later.
NASA Astrophysics Data System (ADS)
Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie
2016-11-01
A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl-/SO42- separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl-/SO42- permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later.
NASA Astrophysics Data System (ADS)
Hiraiwa, Atsushi; Matsumura, Daisuke; Okubo, Satoshi; Kawarada, Hiroshi
2017-02-01
Atomic-layer-deposition (ALD) Al2O3 films are promising as gate insulators of non-Si semiconductor devices. Although they allow relatively small leakage currents just after deposition, ALD Al2O3 films formed at low temperatures are subject to high temperature during fabrication or operation of devices. Therefore, the effect of post-deposition annealing (PDA) on the properties of Al2O3 films is investigated in this study. ALD Al2O3 films formed using H2O oxidant at low temperatures are compacted by PDA, but their mass density and dielectric constant remain approximately unchanged or slightly decrease owing to the desorption of methyl groups contained in the films as impurities. In accordance with these results, the wet etching rate of Al2O3 films is not much reduced by PDA. The conduction current in ALD Al2O3 films formed on Si is reduced by PDA and becomes smaller than that in films formed at the same ALD temperatures as those of PDA. The conduction current for PDA temperatures above 250 °C, however, increases and, accordingly, spoils the merit of low-temperature ALD. Therefore, given that the dielectric constant of annealed films remains low, high-temperature ALD is practically more significant than applying PDA to low-temperature ALD Al2O3 films from the viewpoint of leakage current under the same thermal budget. Space-charge-controlled field emission analysis revealed that, at the aforementioned threshold temperature, PDA abruptly increases the Al2O3/SiO2 interfacial dipoles and simultaneously reduces the amount of the positive charge near the interface. The so-called negative-charge buildup by PDA might be caused by this decrease in the positive charge.
Bedside PDA ligation in premature infants less than 28 weeks and 1000 grams.
Avsar, Mustafa Kemal; Demir, Tolga; Celiksular, Cem; Zeybek, Cenap
2016-10-04
PDA(Patent ductus arteriosus) is a common and clinically important condition which is presented with a number of hemodynamic and respiratory problems such as intraventricular hemorrhage, pulmonary hemorrhage and necrotizing enterocolitis due to increased pulmonary blood flow and stealing from systemic circulation. The incidence of PDA among the infants that were born before the 28th gestational week is as high as 70 %; and spontaneous closure rates in very-low-birth-weight premature neonates(VLBWPN) is around 34 %. The onset, duration, and repeat number of consecutive courses of the prostaglandin synthesis inhibitor medication for PDA closure are still issues of debate. Bed-side PDA closure is a safe surgical procedure in both mature and premature babies. Here we aim to retrospectively present our 26 cases which were less than 28 weeks and 1000 grams that underwent bed-side PDA ligation. This retrospective study included 26 VLBWPN with PDA that underwent bed-side ligation between 2012 and 2015. Babies were born before the 28th gestational week (23-27 weeks) and less than 1000 grams (489-970 gr). Of the 26, 15 were female and 11 were male. Indomethacin was administered to all of the cases as the medical closing agent. The medication was stopped due to unwanted effects in 6 cases. All of the patients took medical treatment before surgery. No surgical mortality occurred during our study. One case of pneumothorax was recorded as late surgical complication. Five of the 26 patients were lost, and the most common cause of mortality was sepsis (in 3 cases). The remaining 21 cases were discharged on days 86-238. The follow-up periods of the patients were 2 moths - 3 years. The most frequent problems encountered after discharge was chronic lung problems. Bed side PDA ligation surgery in the ICU is a safe method for VLBWPN with clinically significant PDA.
Reliability and validity of a questionnaire for self-assessment of complete dentures.
Komagamine, Yuriko; Kanazawa, Manabu; Kaiba, Yoshinori; Sato, Yusuke; Minakuchi, Shunsuke
2014-05-02
Demand for complete denture treatment is expected to rise over several decades. However, to date, no questionnaire on complete dentures, as evaluated by edentulous patients, has been shown to be reliable and valid. This study sought to assess the reliability and validity of Patient's Denture Assessment (PDA), which provides a multidimensional evaluation of dentures among edentulous patients. Patients, who had new complete dentures fabricated at the University Hospital of Dentistry, Tokyo Medical and Dental University through 2009 to 2010, were enrolled. The reliability of the PDA was determined by examining internal consistency and test-retest reliability. Internal consistency for all of the question items and the six subscales was measured using Cronbach's α and average inter-item correlation coefficients among 93 participants. For 33 of these participants, test-retest reliability was determined at a 2 month-interval using the interclass correlation coefficients (ICCs) and 95% confidence interval for the summary scores and the six subscale scores. The PDA was validated in 93 participants by examining the difference in the summary score and the six subscale scores of the PDA before and after replacement with new dentures by the paired t-test. Ability to detect change was also tested in 93 patients using effect size. The Cronbach's α for the PDA ranged from 0.56 to 0.93. The average inter-item correlation coefficients ranged from 0.28 to 0.83. ICCs for the PDA ranged from 0.37 to 0.83. The paired t-test showed a significant difference between the summary score and the six subscale scores before and after replacement with new dentures (p < 0.05) and the effect size was 0.97. The PDA demonstrated good reliability by assessing internal consistency and test-retest reliability. In addition, the PDA demonstrated good validity by assessing discriminant validity. Thus, the PDA could help dentists obtain a detailed understanding of the patients' perceptions in using their dentures.
A Retrospective Study of 1526 Cases of Transcatheter Occlusion of Patent Ductus Arteriosus
Jin, Mei; Liang, Yong-Mei; Wang, Xiao-Fang; Guo, Bao-Jing; Zheng, Ke; Gu, Yan; Lyu, Zhen-Yu
2015-01-01
Background: Patent ductus arteriosus (PDA) is one of the most common congenital heart diseases and began to get treated by transcatheter occlusion since 1997 in China. Since then, several devices have been invented for occluding PDA. This study aimed to evaluate the technical feasibility, safety, and efficacy of transcatheter occlusion of PDA with different devices. Methods: One thousand five hundred and twenty-six patients (537 boys, 989 girls) with PDA from January 1997 to September 2014 underwent descending aortogram and transcatheter occlusion procedure. We retrospectively analyzed data of these patients, including gender, age, weight, size and morphology of PDA, and devices used in transcatheter occlusion, outcomes, and postoperational complications. Results: Median age and median weight were 4.0 years (range: 0.3–52.0 years old) and 15.3 kg (range: 4.5–91.0 kg), respectively. Mean ductal diameter, aortic ductal diameter, ductal length, and pulmonary artery pressure were 3.50 ± 2.15 mm, 10.08 ± 2.46 mm, 7.49 ± 3.02 mm, and 30.21 ± 17.28 mmHg, respectively. Morphology of PDA assessed by descending aortogram was of type A in 1428 patients, type B in 6 patients, type C in 79 patients, type D in 4 patients, and type E in 9 patients according to the classification of Krichenko. Of all the 1526 patients, 1497 patients underwent transcatheter PDA closure, among which 1492 were successful. Devices used were Amplatzer duct occluder I (ADO I, 1280, 85.8%), Cook detachable coils (116, 7.8%), ADO II (ADO II, 68, 4.6%), muscular VSD occluder (12, 0.8%), and Amplatzer vascular plug (16, 1.0%). Conclusions: Excellent occlusion rates with low complication rates were achieved with all devices regardless of PDA types. With transcatheter occlusion technique and devices developing, more patients with PDA can be treated with transcatheter closure both safely and efficiently. PMID:26315073
Amoogzar, Hamid; Shakiba, Ali Mohammad; Derakhshan, Dorna; Ajami, Gholamhossein; Cheriki, Sirous; Borzouee, Mohammad; Edraki, Mohammad Reza; Mehdizadegan, Nima
2015-01-01
The aim of this study was to evaluate the left ventricular systolic and diastolic function before and after transcatheter percutaneous patent ductus arteriosus (PDA) closure. 21 children (age >6 months old) diagnosed with hemodynamically significant PDA underwent percutaneous PDA closure. Conventional, Doppler and tissue Doppler imaging and speckled-derived strain rate echocardiography were done at pre-closure, 1 day (early) and 1 month (late) post-closure. Mean age of the patients (female/male: 1.3) was 17.54 ± 24.7 months with the mean PDA diameter of 3.6 ± 0.8 mm. Systolic measures (ejection fraction, shortening fraction) reduced significantly early after PDA closure (P < 0.05). After 1 month, both improved significantly; ultimately, after 1 month no change was observed in systolic function measures compared with the pre-closure status. Early and late diastolic flow velocities of mitral (E M and A M) reduced considerably in early and late post-closure time (P < 0.05). Both early tissue Doppler early velocity of lateral mitral annulus (E'M) and early to late velocity ratio (E'M/A'M) of lateral mitral annulus decreased significantly (P = 0.02) in early post-closure. After 1 month, E'M increased considerably. (P = 0.01) but E'M/A'M had an insignificant rise (P > 0.05). E M/E'M ratio did not change in early post-closure but it had a considerable reduction in the subsequent month compared with the pre- and early post-closure (P < 0.001 for both occasions). Global and segmental longitudinal strain measures reduced significantly early after PDA closure (P < 0.05) but it improved remarkably in the subsequent month. Transcatheter PDA closure causes a significant decrease in left ventricular performance early after PDA closure which recovers completely within 1 month. Also PDA size can affect post-closure left ventricular function.
A Retrospective Study of 1,526 Cases of Transcatheter Occlusion of Patent Ductus Arteriosus.
Jin, Mei; Liang, Yong-Mei; Wang, Xiao-Fang; Guo, Bao-Jing; Zheng, Ke; Gu, Yan; Lyu, Zhen-Yu
2015-09-05
Patent ductus arteriosus (PDA) is one of the most common congenital heart diseases and began to get treated by transcatheter occlusion since 1997 in China. Since then, several devices have been invented for occluding PDA. This study aimed to evaluate the technical feasibility, safety, and efficacy of transcatheter occlusion of PDA with different devices. One thousand five hundred and twenty-six patients (537 boys, 989 girls) with PDA from January 1997 to September 2014 underwent descending aortogram and transcatheter occlusion procedure. We retrospectively analyzed data of these patients, including gender, age, weight, size and morphology of PDA, and devices used in transcatheter occlusion, outcomes, and postoperational complications. Median age and median weight were 4.0 years (range: 0.3-52.0 years old) and 15.3 kg (range: 4.5-91.0 kg), respectively. Mean ductal diameter, aortic ductal diameter, ductal length, and pulmonary artery pressure were 3.50 ± 2.15 mm, 10.08 ± 2.46 mm, 7.49 ± 3.02 mm, and 30.21 ± 17.28 mmHg, respectively. Morphology of PDA assessed by descending aortogram was of type A in 1428 patients, type B in 6 patients, type C in 79 patients, type D in 4 patients, and type E in 9 patients according to the classification of Krichenko. Of all the 1526 patients, 1497 patients underwent transcatheter PDA closure, among which 1492 were successful. Devices used were Amplatzer duct occluder I (ADO I, 1280, 85.8%), Cook detachable coils (116, 7.8%), ADO II (ADO II, 68, 4.6%), muscular VSD occluder (12, 0.8%), and Amplatzer vascular plug (16, 1.0%). Excellent occlusion rates with low complication rates were achieved with all devices regardless of PDA types. With transcatheter occlusion technique and devices developing, more patients with PDA can be treated with transcatheter closure both safely and efficiently.
Weesepoel, Yannick; Gruppen, Harry; de Bruijn, Wouter; Vincken, Jean-Paul
2014-10-22
Food products enriched with fatty acid-esterified xanthophylls may result in deviating dietary apo-carotenoids. Therefore, free astaxanthin and its mono- and dipalmitate esters were subjected to two degradation processes in a methanolic model system: light-accelerated autoxidation and hypochlorous acid/hypochlorite (HOCl/OCl(-)) bleaching. Reversed phase ultrahigh-performance liquid chromatography photodiode array with in-line electrospray ionization mass spectrometry (RP-UHPLC-PDA-ESI-MS) was used for assessment of degradation products. Apo-astaxanthinals and -astaxanthinones containing 3 (apo-9) to 10 (apo-8') conjugated double bonds were found upon autoxidation for all three types of astaxanthin (except free apo-8'-astaxanthinal). Fragmentation of [M + H](+) and [M + Na](+) parent masses of apo-astaxanthins from dipalmitate astaxanthin indicated palmitate esterification. Astaxanthin monopalmitate degradation resulted in a mixture of free and palmitate apo-astaxanthins. HOCl/OCl(-) rapidly converted the astaxanthins into a mixture of epoxy-apo-9- and epoxy-apo-13-astaxanthinones. The palmitate ester bond was hardly affected by autoxidation, whereas for HOCl/OCl(-) the ester bond of the apo-astaxanthin palmitoyl esters was degraded.
Remote data entry and retrieval for law enforcement
NASA Astrophysics Data System (ADS)
Kwasowsky, Bohdan R.; Capraro, Gerard T.; Berdan, Gerald B.; Capraro, Christopher T.
1997-02-01
Law enforcement personnel need to capture and retrieve quality multimedia data in `real time' while in the field. This is not done today, for the most part. Most law enforcement officers gather data on handwritten forms and retrieve data via voice communications or fax. This approach is time consuming, costly, prone to errors, and may require months before some data are entered into a usable law enforcement database. With advances in the computing and communications industries, it is now possible to communicate with anyone using a laptop computer or personal digital assistant (PDA), given a phone line, an RF modem, or cellular capability. Many law enforcement officers have access to laptop computers within their vehicles and can stay in touch with their command center and/or retrieve data from local, state, or federal databases. However, this same capability is not available once they leave the vehicle or if the officer is on a beat, motorcycle, or horseback. This paper investigates the issues and reviews the state of the art for integrating a PDA into the gathering and retrieving of multimedia data for law enforcement.
Volume guarantee ventilation during surgical closure of patent ductus arteriosus.
Keszler, Martin; Abubakar, Kabir
2015-01-01
Surgical closure of patent ductus arteriosus (PDA) is associated with adverse outcomes. Surgical exposure requires retraction of the lung, resulting in decreased aeration and compliance. Optimal respiratory support for PDA surgery is unknown. Experience with volume guarantee (VG) ventilation at our institution led us to hypothesize that surgery would be better tolerated with automatic adjustment of pressure by VG to maintain tidal volume (VT) during retraction. The objective of this study was to describe ventilator support, VT, and oxygenation of infants supported with VG during PDA surgery. Ventilator variables, oxygen saturation, and heart rate were recorded during PDA surgery in a convenience sample of infants during PDA closure on VG. Pressure limit increased 11% and set VT was 26% lower during lung retraction. Fentanyl and pancuronium/vecuronium were used for anesthesia/muscle relaxation. Longitudinal data were analyzed by analysis of variance for repeated measures. Seven infants, 25.4 ± 1.5 weeks and 723 ± 141 g, underwent closure of PDA on VG at a mean age 29.9 days. No air leak, bradycardia, or death occurred. Target VT was maintained with a modest increase in inflation pressure. Oxygenation remained adequate. VG avoided hypoxemia and maintained adequate VT with only a modest increase in peak inflation pressure and thus may be a useful mode during PDA surgery. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Pan, Xiang-Bin; Ouyang, Wen-Bin; Wang, Shou-Zheng; Liu, Yao; Zhang, Da-Wei; Zhang, Feng-Wen; Pang, Kun-Jing; Zhang, Zhe; Hu, Sheng-Shou
2016-07-01
Percutaneous patent ductus arteriosus (PDA) occlusion has become the preferred therapeutic option, which uses fluoroscopy as the guidance. To reduce the x-ray exposure, PDA occlusion using the Amplatzer Duct Occluder II (ADO II) under guidance of transthoracic echocardiography only was conducted. This single center study aims to access the safety and efficiency of this new strategy. From June 2013 to May 2015, 63 consecutive PDA patients underwent transthoracic echocardiography-guided PDA occlusion through the femoral artery. Outpatient follow-up was conducted at 1, 3, and 6 months, and yearly. Sixty-two patients successfully underwent echocardiography-guided percutaneous PDA occlusion. One patient was converted to minimally invasive transthoracic occlusion due to failure of delivery sheath passage through tortuous PDA. Mean procedure duration was 24.3 ± 7.0 minutes; ADO II diameter averaged 4.6 ± 0.9 mm; 8 cases showed traces of residual shunt immediately after operation which resolved after 24 hours; and mean hospital stay was 3.4 ± 0.5 days. There was no occluder migration, hemolysis, pericardial effusion, pulmonary branch or aortic stenosis at mean 13.5 ± 4.8 months follow-up. This study demonstrated that percutaneous PDA occlusion can be successfully performed under guidance of transthoracic echocardiography only and appears safe and effective while avoiding radiation and contrast agent use. © 2016, Wiley Periodicals, Inc.
Wang, Yan; Gu, Fu-Qiang; Ni, Li-Juan; Liang, Kun; Marcus, Kyle; Liu, Shu-Li; Yang, Fan; Chen, Jin-Ju; Feng, Zhe-Sheng
2017-11-30
Conductive polymer composites (CPCs) containing nanoscale conductive fillers have been widely studied for their potential use in various applications. In this paper, polypyrrole (PPy)/polydopamine (PDA)/silver nanowire (AgNW) composites with high electromagnetic interference (EMI) shielding performance, good adhesion ability and light weight are successfully fabricated via a simple in situ polymerization method followed by a mixture process. Benefiting from the intrinsic adhesion properties of PDA, the adhesion ability and mechanical properties of the PPy/PDA/AgNW composites are significantly improved. The incorporation of AgNWs endows the functionalized PPy with tunable electrical conductivity and enhanced EMI shielding effectiveness (SE). By adjusting the AgNW loading degree in the PPy/PDA/AgNW composites from 0 to 50 wt%, the electrical conductivity of the composites greatly increases from 0.01 to 1206.72 S cm -1 , and the EMI SE of the composites changes from 6.5 to 48.4 dB accordingly (8.0-12.0 GHz, X-band). Moreover, due to the extremely low density of PPy, the PPy/PDA/AgNW (20 wt%) composites show a superior light weight of 0.28 g cm -3 . In general, it can be concluded that the PPy/PDA/AgNW composites with tunable electrical conductivity, good adhesion properties and light weight can be used as excellent EMI shielding materials.
Kang, Soo Jung; Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin
2017-12-01
To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Pharmacological closures were attempted at postnatal day 2-3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function.
Chock, Valerie Y; Goel, Veena V; Palma, Jonathan P; Luh, Thomas M; Wang, Nichole A; Gaskari, Shabnam; Punn, Rajesh; Silverman, Norman H; Benitz, William E
2017-08-01
Objective This historical cohort study investigated how a shift toward a more conservative approach of awaiting spontaneous closure of the patent ductus arteriosus (PDA) in preterm infants has affected neonatal outcomes and resource utilization. Methods We retrospectively studied very low birth weight infants diagnosed with a PDA by echocardiogram (ECHO) in 2006-2008 (era 1), when medical or surgical PDA management was emphasized, to those born in 2010-2012 (era 2) when conservative PDA management was encouraged. Multiple regression analyses adjusted for gestational age were performed to assess differences in clinical outcomes and resource utilization between eras. Results More infants in era 2 (35/89, 39%) compared with era 1 (22/120, 18%) had conservative PDA management ( p < 0.01). Despite no difference in surgical ligation rate, infants in era 2 had ligation later (median 24 vs. 8 days, p < 0.0001). There was no difference in clinical outcomes between eras, while number of ECHOs per patient was the only resource measure that increased in era 2 (median 3 vs. 2 ECHOs, p = 0.003). Conclusion In an era of more conservative PDA management, no increase in adverse clinical outcomes or significant change in resource utilization was found. Conservative PDA management may be a safe alternative for preterm infants. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Sugiyama, Y; Sasajima, J; Mizukami, Y; Koizumi, K; Kawamoto, T; Ono, Y; Karasaki, H; Tanabe, H; Fujiya, M; Kohgo, Y
2016-06-01
The hedgehog pathway is known to promote proliferation of pancreatic ductal adenocarcinoma (PDA) and has been shown to restrain tumor progression. To understand how hedgehog causes these effects, we sought to carefully examine protein expression of hedgehog signaling components during different tumor stages. Genetically engineered mice, Pdx1-Cre;LSL-KrasG12D and Pdx1-Cre;LSL-KrasG12D;p53lox/+, were utilized to model distinct phases of tumorigenesis, pancreatic intraepithelial neoplasm (PanIN) and PDA. Human pancreatic specimens of intraductal papillary mucinous neoplasm (IPMN) and PDA were also employed. PanIN and IPMN lesions highly express Sonic Hedgehog, at a level that is slightly higher than that observed in PDA. GLI2 protein is also expressed in both PanIN/IPMN and PDA. Although there was no difference in the nuclear staining, the cytoplasmic GLI2 level in PDA was modest in comparison to that in PanIN/IPMN. Hedgehog interacting protein was strongly expressed in the precursors, whereas the level in PDA was significantly attenuated. There were no differences in expression of Patched1 at early and late stages. Finally, a strong correlation between Sonic Hedgehog and GLI2 staining was found in both human and murine pancreatic tumors. The results indicate that the GLI2 protein level could serve as a feasible marker of ligand-dependent hedgehog activation in pancreatic neoplasms.
Goodrich, Kimberly R; Kyles, Andrew E; Kass, Phillip H; Campbell, Fiona
2007-01-01
To compare procedure time, complications, mortality, and short-term outcome in dogs with patent ductus arteriosus (PDA) treated by surgical ligation (SL) or transarterial coil occlusion (TCO). Retrospective study. Dogs with PDA (n=204). Medical records of dogs treated for PDA were reviewed. Dogs treated by SL when it was the primary method used for PDA treatment (1993-1998) were compared with dogs treated by TCO when it was the primary method used for PDA treatment (1999-2003). Dogs treated during the transition between techniques, dogs treated with SL (1999-2003) and dogs treated with TCO before 1999, as well as dogs with pulmonary hypertension, or bidirectional or reversed (right-to-left) flow through the PDA were excluded from analysis. Age, weight, gender distribution, and procedure times (P=.43) were similar for both groups. Major complications were more common with SL (12% versus 4.3%; P=.035) whereas minor complications were more common with TCO (12% versus 26%; P=.015). Initial success rate was higher for SL (94%) compared with TCO (84%; P=.027). There was no significant difference in mortality between SL (5.6%) and TCO (2.6%; P=.27). Both SL and TCO are acceptable PDA treatments with comparable mortality; however, SL was associated with a higher risk of major complications and TCO was associated with a lower initial success rate.
Library Services for Users of Personal Digital Assistants: A Needs Assessment and Program Evaluation
ERIC Educational Resources Information Center
Carney, Stephen; Koufogiannakis, Denise; Ryan, Pam
2007-01-01
Research was undertaken to guide development of services for personal digital assistant (PDA) users at the University of Alberta Libraries. A variety of qualitative methods were used to assess user satisfaction with current PDA services and identify potential PDA services for the libraries and resources. The research and needs assessment results…
The impact of a dedicated patent ductus arteriosus ligation team on neonatal health-care outcomes.
Resende, M H F; More, K; Nicholls, D; Ting, J; Jain, A; McNamara, P J
2016-06-01
The decision to perform patent ductus arteriosus (PDA) ligation is controversial. Patient selection is oftentimes poorly standardized, leading to delays in referral and inappropriate intervention. A system for PDA ligation categorization and triaging process was introduced in 2006 at a quaternary hospital in Canada to streamline referrals and enhance perioperative care. We aimed to evaluate the impact of this dedicated PDA ligation triaging system comparing pre- and postimplementation of this system. We performed a retrospective chart review. Demographic and cardiorespiratory data of neonates ⩽30 weeks gestation age at birth, who were referred for and/or had a PDA ligation performed during two distinct epochs (EPOCH 1 (2003 to 2005) and EPOCH 2 (2010 to 2012)), were analyzed. All surgeries were performed at The Hospital for Sick Children, the regional referral center for PDA ligation. The primary outcome was incidence of PDA ligation and procedural cancellations. Secondary outcomes included postoperative need for cardiovascular or respiratory support. Subgroup analysis was performed in neonates <1000 vs >1000 g at the time of surgery during both epochs. A total of 198 neonates underwent surgery with no difference in baseline demographics between epochs. The incidence of PDA ligation as a proportion of total live births under 30 weeks in Central East Region of Ontario was lower in the second epoch (EPOCH 1: 117/1092 (10.7%) vs EPOCH 2: 81/1520 (5.3%)). During the second epoch, 24% of referrals for surgery were canceled after review by our PDA ligation team. There were no overall differences in the proportion of neonates with oxygenation failure, ventilation failure or Post-Ligation Cardiac Syndrome (PLCS), after surgery, between epochs. The proportion of neonates who developed systemic hypotension was higher in patients <1000 g (n=34 (34%) vs n=17 (17.4%), P=0.01) at the time of surgery. In addition, we identified a reduction in the proportion of neonates <1000 g who developed PLCS in EPOCH 2. On the contrary, there was an increase in the proportion of neonates >1000 g who developed ventilation failure in EPOCH 2. The presence of dedicated triaging and management system enhances efficiency of referral process through careful selection of patients for PDA ligation and optimizes perioperative management. We demonstrated a reduction in the incidence of PDA ligation without any negative impact on short-term neonatal morbidity. The use of targeted neonatal echocardiography in the assessment of PDA shunt volume and guiding postoperative decision making is likely to have contributed to these findings.
Elhoff, Justin J; Ebeling, Myla; Hulsey, Thomas C; Atz, Andrew M
2016-01-01
A recent review supports a strategy of deferring treatment of patent ductus arteriosus (PDA) in the preterm neonate until at least the second week after birth. In light of previous suggestion that later initiation of treatment may be less efficacious for closing PDAs it is reasonable to question if delayed treatment may be less effective. We conducted a single center retrospective review of a neonatal intensive care unit database of infants ≤37 weeks gestation with the diagnosis of PDA and treated with indomethacin from 1999 to 2007. We determined gestational age (GA), timing of indomethacin initiation, and status of the PDA at hospital discharge. Treatment failure was defined as neonates requiring further intervention to close their PDA or those who died without echo-proven PDA closure. Of the 341 infants meeting the study criteria, 77 (23%) had defined treatment failure. The failure group had a younger median GA of 25 weeks (interquartile range [IQR], 24-26) vs. 28 weeks (IQR, 26-30) for the successful group (P < .0001). The failure group had a median treatment initiation on day of life (DOL) 4 (IQR, 1-8) compared with DOL 3 (IQR, 1-6) for those in the successful group (P = .15). Taken as a whole, infants treated after DOL 5 were significantly more likely to have treatment failure (30.1% vs. 19.3% for those treated DOL 1-5, P = .03). Our study confirms that younger GA at birth is correlated with increased likelihood of failed PDA closure. We also show a trend indicating that later initiation of treatment may decrease the chances of successfully closing a PDA. Future examination of PDA management should consider the potential unintended consequences that may accompany a delayed treatment strategy. © 2015 Wiley Periodicals, Inc.
Syed, Ayeshah; Mohd Don, Zuraidah; Ng, Chirk Jenn; Lee, Yew Kong; Khoo, Ee Ming; Lee, Ping Yein; Lim Abdullah, Khatijah; Zainal, Azlin
2017-01-01
Objective To investigate whether the use of apatient decision aid (PDA) for insulin initiation fulfils its purpose of facilitating patient-centred decision-making through identifying how doctors and patients interact when using the PDA during primary care consultations. Design Conversation analysis of seven single cases of audio-recorded/video-recorded consultations between doctors and patients with type 2 diabetes, using a PDA on starting insulin. Setting Primary care in three healthcare settings: (1) one private clinic; (2) two public community clinics and (3) one primary care clinic in a public university hospital, in Negeri Sembilan and the Klang Valley in Malaysia. Participants Clinicians and seven patients with type 2 diabetes to whom insulin had been recommended. Purposive sampling was used to select a sample high in variance across healthcare settings, participant demographics and perspectives on insulin. Primary outcome measures Interaction between doctors and patients in a clinical consultation involving the use of a PDA about starting insulin. Results Doctors brought the PDA into the conversation mainly by asking information-focused ‘yes/no’ questions, and used the PDA for information exchange only if patients said they had not read it. While their contributions were limited by doctors’ questions, some patients disclosed issues or concerns. Although doctors’ PDA-related questions acted as a presequence to deliberation on starting insulin, their interactional practices raised questions on whether patients were informed and their preferences prioritised. Conclusions Interactional practices can hinder effective PDA implementation, with habits from ordinary conversation potentially influencing doctors’ practices and complicating their implementation of patient-centred decision-making. Effective interaction should therefore be emphasised in the design and delivery of PDAs and in training clinicians to use them. PMID:28490553
Natural evolution of patent ductus arteriosus in the extremely preterm infant.
Rolland, Audrey; Shankar-Aguilera, Shivani; Diomandé, Douty; Zupan-Simunek, Véronique; Boileau, Pascal
2015-01-01
The persistence of the patent ductus arteriosus (PDA) is frequently encountered in very preterm infants. Neither preventive nor curative treatments of PDA have been shown to improve the outcome of these infants. Since no consensus on optimal treatment of PDA is established, we evaluated the rate of spontaneous PDA closure in infants born before 28 weeks of gestation. We studied a retrospective cohort of 103 infants (gestational age 24-27 weeks) admitted to our neonatal intensive care unit from 1 June 2008 to 31 July 2010. Maternal and neonatal characteristics were collected. The PDA was defined by the persistence of ductal patency after 72 h and was followed up by regular echocardiography. Twelve infants died within the first 72 h and were excluded from the analysis. Among 91 infants analysed, 8 (9%) closed their ductus arteriosus before 72 h and the ductus could not be determined patent in 13. Of the 70 infants with a PDA still persistent, one underwent surgical ligation and echocardiography showed spontaneous closure in 51 (73%) of them. In the remaining 18 infants, the date of PDA closure could not be determined either because of their death (n=11) or due to discharge (n=7). Overall, a spontaneous closure of the ductus arteriosus was observed in 59 of the 91 infants. We have to question whether exposure to the risks of therapeutic interventions targeted for ductal closure is warranted since a PDA closes spontaneously in at least 73% of infants born before 28 weeks. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Harada, Kenji; Toyono, Manotomo; Tamura, Masamichi
2004-06-01
Transthoracic Doppler echocardiography provides noninvasive measurements of coronary blood flow in the left anterior descending coronary artery (LAD). This method has the potential to show the effects of acute changes in loading conditions on blood flow. Coil closure of patent ductus arteriosus (PDA) is a model of acute changes in blood pressure and left ventricular (LV) preload that influences coronary blood flow. We applied this technique to assess the coronary blood flow changes for patients with PDA before and immediately after PDA coil closure. We examined 9 patients (1.8 +/- 1.1 years) with simple PDA and 8 age-matched healthy children. LV dimensions and LV mass were measured. Maximum peak flow velocity and flow volume in the LAD were measured. Pulmonary to systemic flow ratios (Qp/Qs) were obtained by cardiac catheterization. After PDA coil closure, LV end-diastolic dimension decreased, and systolic and diastolic blood pressures increased significantly. The maximum peak flow velocity, LAD flow volume, and the ratio of LAD flow volume to LV mass increased significantly. The changes in maximum peak flow velocity and the ratio of LAD flow volume to LV mass (F/M) correlated positively with the changes in diastolic pressure and Qp/Qs. In 5 patients who had Qp/Qs > 1.5, the mean F/M was significantly lower compared with control subjects, but they increased to normal values after coil closure of PDA. PDA coil closure increases diastolic pressure and decreases Qp/Qs, resulting in improvement of myocardial perfusion. These findings provide new insights into the relationship between cardiac function and coronary circulation in pediatric patients with heart diseases associated with PDA.
Nitzan, Itamar; Hammerman, Cathy; Fink, Daniel; Nitzan, Meir; Koppel, Robert; Bromiker, Ruben
2018-06-26
The ductus arteriosus is a blood vessel that connects the pulmonary artery to the descending aorta during fetal life and generally undergoes spontaneous closure shortly after birth. In premature neonates it often fails to close (patent ductus arteriosus - PDA), which can result in diversion of a significant part of the left-ventricular cardiac output to the pulmonary circulation. This left-to-right shunt may result in significant increase of pulmonary blood flow and decrease of systemic perfusion (hemodynamically significant PDA - hsPDA), which may lead to severe neonatal morbidity. The study objective was to find the relationship between hsPDA and perfusion index (PI), a photoplethysmographic parameter, related to systemic perfusion. Approach. PI measures the relative systolic increase in tissue light absorption due to the systolic increase in the tissue blood volume. PI has been found to be directly related to tissue perfusion, and is therefore expected to be affected by hsPDA. Main results. PI was found to be higher in preterm neonates with hsPDA after first week of life, in comparison to those with closed DA, despite the lower systemic perfusion, probably due to reverse flow during diastole. Significance. In our study, perfusion index increased despite the lower systemic perfusion, indicating that in neonates with hsPDA, perfusion index is not necessarily a measure of perfusion. Nevertheless, PI can be used as a screening tool for suspicious PDA, in order to select a relatively small group of neonates for a more definitive examination by echocardiography, which is not suitable for universal screening. . © 2018 Institute of Physics and Engineering in Medicine.
Rosito, G; Sum, K; Chorne, N
2010-10-01
Indomethacin, a non-selective inhibitor of prostaglandin synthesis, is the gold standard treatment for patent ductus arteriosus (PDA). Indomethacin has been shown to permanently close the ductus and when given prophylactically, it reduces the incidence of PDA (1, 2). This study compares PDA closure and surgical ligation rates between patients using two different indomethacin administration protocols. This is a retrospective comparison analysis of 72 neonates, who received one of two indomethacin administration protocols. Our previous protocol suggested an initial dose of 0·2 mg/kg followed by two 0·1 mg/kg, with doses infused over 4 h and a 24-h dosing interval. A new potentially more useful protocol using the same mg/kg dose regimen but with doses infused over 30 min and a 12-h dosing interval, was evaluated. Each neonate was allowed three courses of treatment before surgical ligation was performed for persistent PDA. There were no statistically significant differences between the two protocol groups when comparing percentages of neonates with gestational age≤28 weeks, birth weight≤1000 g, male gender or receiving indomethacin for the indication of PDA prophylaxis vs. treatment. There was a trend towards a higher PDA closure rate and subsequently a lower PDA ligation rate in the new protocol when compared with the previous protocol. In this small population of premature neonates, there was a trend, but no significant difference, towards increasing PDA closure and lower surgical ligation rates in neonates given indomethacin with more frequent dosing and shorter infusion time. A well-powered randomized controlled trial is now needed. Copyright © 2010 The Authors. JCPT © 2010 Blackwell Publishing Ltd.
Polydopamine and MnO2 core-shell composites for high-performance supercapacitors
NASA Astrophysics Data System (ADS)
Hou, Ding; Tao, Haisheng; Zhu, Xuezhen; Li, Maoguo
2017-10-01
Polydopamine and MnO2 core-shell composites (PDA@MnO2) for high-performance supercapacitors had been successfully synthesized by a facile and fast method. The morphology, crystalline phase and chemical composition of PDA@MnO2 composites are characterized using SEM, TEM, XRD, EDS and XPS. The performance of PDA@MnO2 composites are further investigated by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy in 1 M Na2SO4 electrolyte. The PDA@MnO2 core-shell nanostructure composites exhibit a high capacitance of 193 F g-1 at the current density of 1A g-1 and retained over 81.2% of its initial capacitance after 2500 cycles of charge-discharge at 2 A g-1. The results manifest that the PDA@MnO2 composites can be potentially applied in supercapacitors.
Gallo, Kaitlin P.; Chan, Priscilla T.; Buzzella, Brian A.; Whitton, Sarah W.; Pincus, Donna B.
2012-01-01
Previous research findings have shown positive effects of cognitive-behavioral therapy for primary anxiety disorders as well as for non-primary, co-occurring anxiety disorders. In this study, we analyzed data from an existing randomized controlled trial of intensive treatment for Panic Disorder with or without Agoraphobia (PDA) to examine the effects of the treatment on comorbid psychiatric diagnoses. The overall frequency and severity of aggregated comorbid diagnoses decreased in a group of adolescents who received an 8-day treatment for PDA. Results suggest that an 8-day treatment for PDA can alleviate the symptoms of some specific comorbid clinical diagnoses; specifically Specific Phobias, Generalized Anxiety Disorder, and Social Phobia. These findings suggest that an intensive treatment for PDA is associated with reductions in comorbid symptoms even though disorders other than PDA are not specific treatment targets. PMID:22304887
Gallo, Kaitlin P; Chan, Priscilla T; Buzzella, Brian A; Whitton, Sarah W; Pincus, Donna B
2012-03-01
Previous research findings have shown positive effects of cognitive-behavioral therapy for primary anxiety disorders as well as for nonprimary, co-occurring anxiety disorders. In this study, we analyzed data from an existing randomized controlled trial of intensive treatment for panic disorder with or without agoraphobia (PDA) to examine the effects of the treatment on comorbid psychiatric diagnoses. The overall frequency and severity of aggregated comorbid diagnoses decreased in a group of adolescents who received an 8-day treatment for PDA. Results suggest that an 8-day treatment for PDA can alleviate the symptoms of some specific comorbid clinical diagnoses; in particular specific phobias, generalized anxiety disorder, and social phobia. These findings suggest that an intensive treatment for PDA is associated with reductions in comorbid symptoms even though disorders other than PDA are not specific treatment targets. Copyright © 2011. Published by Elsevier Ltd.
Kuiper, RuthAnne
2010-01-01
The utility of personal digital assistants (PDA) as a point of care resource in health care practice and education presents new challenges for nursing faculty. While there is a plethora of PDA resources available, little is known about the variables that effect student learning and technology adoption. In this study nursing students used PDA software programs which included a drug guide, medical dictionary, laboratory manual and nursing diagnosis manual during acute care clinical experiences. Analysis of student journals comparative reflective statements about the PDA as an adjunct to other available resources in clinical practice are presented. The benefits of having a PDA included readily available data, validation of thinking processes, and facilitation of care plan re-evaluation. Students reported increased frequency of use and independence. Significant correlations between user perceptions and computer self-efficacy suggested greater confidence in abilities with technology resulting in increased self-awareness and achievement of learning outcomes.
Clyman, Ronald I.
2013-01-01
A persistent left-to right shunt through a patent ductus arteriosus (PDA) increases the rate of hydrostatic fluid filtration into the lung’s interstitium, impairs pulmonary mechanics, and prolongs the need for mechanical ventilation. In preclinical trials, pharmacologic PDA closure leads to improved alveolarization and minimizes the impaired postnatal alveolar development that is the pathologic hallmark of the “new bronchopulmonary dysplasia (BPD)”. Although early pharmacologic closure of the PDA decreases the incidence of pulmonary hemorrhage, intraventricular hemorrhage, and the need for PDA ligation, there is little evidence from controlled, clinical trials to support or refute a causal role for the PDA in the development of BPD. On the other hand, evidence from epidemiologic, preclinical, and randomized controlled clinical trials demonstrate that early ductus ligation is an independent risk factor for the development of BPD and may directly contribute to the neonatal morbidities it is trying to prevent. PMID:23582964
Use of an electronic cognitive aid by a person with Korsakoff syndrome.
de Joode, E A; van Boxtel, M P J; Hartjes, P; Verhey, F R J; van Heugten, C M
2013-11-01
The purpose of the current study was to evaluate the feasibility and the effectiveness of the use of a customized personal digital assistant (PDA) to support cognitive functioning in a person with Korsakoff syndrome. The PDA was compared with no external support and the use of a memory watch in a single case experimental design. Three main personal goal tasks were defined: "arrive at appointments on time", "execute a long-term task successfully", and "remember to ask for medication". No significant differences were found between the use of the memory watch and the use of the customized PDA. PDA use was perceived as feasible and effective and was considered as a more comprehensive aid than the memory watch. This study shows that a person with Korsakoff syndrome is able to use and benefit from a customized PDA. Replication of these findings in a larger effectiveness study is necessary.
NASA Astrophysics Data System (ADS)
Yang, Xueliang; Liu, Wei; Chen, Jingwei; Sun, Yun
2018-04-01
Using metal oxides to form a carrier-selective interface on crystalline silicon (c-Si) has recently generated considerable interest for use with c-Si photovoltaics because of the potential to reduce cost. n-type oxides, such as MoO3, V2O5, and WO3, have been widely studied. In this work, a p-type oxide, Cu-doped NiO (NiO:Cu), is explored as a transparent hole-selective contact to n-Si. An ultrathin SiOx layer, fabricated by a wet-chemical method (wet-SiOx), is introduced at the NiO:Cu/n-Si interface to achieve a tunnelling junction solar cell. Interestingly, it was observed that the interface quality of the NiO:Cu/wet-SiOx/n-Si heterojunction was dramatically enhanced by post-deposition annealing (PDA) at a temperature of 200 °C. Our device exhibits an improved power conversion efficiency of 10.8%, which is the highest efficiency among NiO/Si heterojunction photo-electric devices to date. It is demonstrated that the 200 °C PDA treatment enhances the built-in field by a reduction in the interface density of states (Dit) but does not influence the work function of the NiO:Cu thin layer. This stable work function after the PDA treatment is in conflict with the changed built-in field according to the Schottky model. Thus, the Bardeen model is introduced for this physical insight: the enhancement of the built-in field originates from the unpinning of the Fermi levels of NiO:Cu and n-Si by the interface state reduction.
Bhola, Kavita; Foster, Jann P; Osborn, David A
2015-11-03
Patent ductus arteriosus (PDA) is associated with mortality and morbidity in preterm infants. Phototherapy is a common treatment for jaundice in preterm infants. However, phototherapy has been associated with failure of closure of the ductus arteriosus in preterm infants. To determine if chest shielding of preterm infants receiving phototherapy reduces the incidence of clinically and/or haemodynamically significant PDA and reduces morbidity secondary to PDA. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library; 2015, Issue 3), MEDLINE, EMBASE, CINAHL, previous reviews, cross-references, abstracts, proceedings of scientific meetings, and trial registries through March 2015. Randomised controlled trials (RCTs), cluster-RCTs, or quasi-RCTs of chest shielding during phototherapy compared to sham shielding or no shielding for the prevention of a haemodynamically or clinically significant PDA in preterm infants. Three review authors independently assessed studies for eligibility and quality and extracted data. We defined a clinically significant PDA as the presence of a PDA with clinical signs of an effect on organ function attributable to the ductus arteriosus. We defined a haemodynamically significant PDA as clinical and/or echocardiographic signs of a significant ductus arteriosus effect on blood flow. We included two small trials enrolling very preterm infants (Rosenfeld 1986; Travadi 2006). We assessed both as at high risk of bias. No study reported clinically significant PDA, defined as the presence of a PDA with clinical symptoms or signs attributable to the effect of a ductus arteriosus on organ function. Rosenfeld 1986 reported a non-significant reduction in haemodynamically significant PDA with left atrial to aortic root ratio greater than 1.2 (risk ratio (RR) 0.23, 95% confidence interval (CI) 0.05 to 1.01; 74 infants) but a statistically significant risk difference (RD -0.18, 95% CI -0.34 to -0.03; number needed to treat for an additional beneficial outcome (NNTB) 5, 95% CI 3 to 33). Rosenfeld 1986 reported a significant reduction in PDA detected by murmur (RR 0.50, 95% CI 0.29 to 0.88; RD -0.30, 95% CI -0.52 to -0.08; NNTB 3, 95% CI 2 to 12; 74 infants). Rosenfeld 1986 reported a significant reduction in treatment with indomethacin (RR 0.12, 95% CI 0.02 to 0.88; RD -0.21, 95% CI -0.35 to -0.06; NNTB 5, 95% CI 3 to 17; 74 infants), and only one infant had a ductal ligation in the no-shield group. There were no other significant outcomes, including mortality to discharge or 28 days, days in oxygen, days on mechanical ventilation, days in hospital, intraventricular haemorrhage, retinopathy of prematurity, or exchange transfusion. The available evidence is very low quality and insufficient to assess the safety or efficacy of chest shield during phototherapy for prevention of PDA in preterm infants. Further trials of chest shielding are warranted, particularly in settings where infants are not receiving prophylactic or early echocardiographic targeted cyclo-oxygenase inhibitors for PDA.
Gao, Xiang; Zhang, Xiaohong; Song, Jinlin; Xu, Xiao; Xu, Anxiu; Wang, Mengke; Xie, Bingwu; Huang, Enyi; Deng, Feng; Wei, Shicheng
2015-01-01
The construction of functional biomimetic scaffolds that recapitulate the topographical and biochemical features of bone tissue extracellular matrix is now of topical interest in bone tissue engineering. In this study, a novel surface-functionalized electrospun polycaprolactone (PCL) nanofiber scaffold with highly ordered structure was developed to simulate the critical features of native bone tissue via a single step of catechol chemistry. Specially, under slightly alkaline aqueous solution, polydopamine (pDA) was coated on the surface of aligned PCL nanofibers after electrospinning, followed by covalent immobilization of bone morphogenetic protein-7-derived peptides onto the pDA-coated nanofiber surface. Contact angle measurement, Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed the presence of pDA and peptides on PCL nanofiber surface. Our results demonstrated that surface modification with osteoinductive peptides could improve cytocompatibility of nanofibers in terms of cell adhesion, spreading, and proliferation. Most importantly, Alizarin Red S staining, quantitative real-time polymerase chain reaction, immunostaining, and Western blot revealed that human mesenchymal stem cells cultured on aligned nanofibers with osteoinductive peptides exhibited enhanced osteogenic differentiation potential than cells on randomly oriented nanofibers. Furthermore, the aligned nanofibers with osteoinductive peptides could direct osteogenic differentiation of human mesenchymal stem cells even in the absence of osteoinducting factors, suggesting superior osteogenic efficacy of biomimetic design that combines the advantages of osteoinductive peptide signal and highly ordered nanofibers on cell fate decision. The presented peptide-decorated bone-mimic nanofiber scaffolds hold a promising potential in the context of bone tissue engineering.
Rational combinations of immunotherapy for pancreatic ductal adenocarcinoma.
Blair, Alex B; Zheng, Lei
2017-06-01
The complex interaction between the immune system, the tumor and the microenvironment in pancreatic ductal adenocarcinoma (PDA) leads to the resistance of PDA to immunotherapy. To overcome this resistance, combination immunotherapy is being proposed. However, rational combinations that target multiple aspects of the complex anti-tumor immune response are warranted. Novel clinical trials will investigate and optimize the combination immunotherapy for PDA.
DexterNet: An Open Platform for Heterogeneous Body Sensor Networks and Its Applications
2008-12-19
motion, ECG PC, PDA 802.15.4 No No ALARM-NET pulse oximetry STARGATE Bluetooth No Yes [19] motion, ECG PDA, PC 802.11 (temperature, light, PIR) DexterNet...motion, ECG PDA 802.15.4 Yes Possible via SPINE EIP, GPS PC (e.g., air pollution sensor) MICAz, SHIMMER uses MICAz sensors and STARGATE to relay the
Kwon, Il Kyoung; Song, Min Sun; Won, Sang Ho; Choi, Seung Phill; Kim, Moonil; Sim, Sang Jun
2012-01-23
A method in which a permanent magnet is introduced onto polydiacetylene (PDA) vesicle chips is introduced for enhancement of the fluorescence of PDA vesicles. This strategy can be applied to general antibody-based PDA vesicle chips to detect clinically important biomarkers for disease diagnosis. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Wang, Wensheng; Nomura, Kenji; Yamaguchi, Hideshi; Nakamura, Ko; Eshita, Takashi; Ozawa, Soichiro; Takai, Kazuaki; Mihara, Satoru; Hikosaka, Yukinobu; Hamada, Makoto; Kataoka, Yuji
2017-10-01
We investigated the crystallization mechanisms of sputter-deposited La-doped Pb(Zr,Ti)O3 (PLZT) on a Pt/Ti metal stack in the postdeposition annealing (PDA) at 600 °C in O2-mixed Ar ambient. As-deposited amorphous PLZT generally transforms to a perovskite phase over 550 °C through a metastable pyrochlore phase during the PDA. We found that the O2 content of the PDA ambient crucially affects the pyrochlore-perovskite transformation (PPT) speed. While an O2 content much higher than 2% of the PDA ambient suppresses PPT, an O2 content much lower than 2% enhances PPT. An O2 content around of 2% of the PDA suppresses PPT near the surface of PLZT and simultaneously keeps PPT fast in the inner regions of PLZT in the pyrochlore phase because of the O2 diffusion limit from the PLZT surface, eventually resulting in almost only the growth of highly {111} oriented columnar PLZT on Pt, which reveals better electric properties than those obtained by the PDA with the ambient of O2 contents much higher or lower than 2%.
Development of a Diagnostic Clinical Score for Hemodynamically Significant Patent Ductus Arteriosus
Kindler, Annemarie; Seipolt, Barbara; Heilmann, Antje; Range, Ursula; Rüdiger, Mario; Hofmann, Sigrun Ruth
2017-01-01
There is no consensus about the hemodynamic significance and, therefore, the need to treat a persistent ductus arteriosus in preterm newborns. Since the diagnosis of a hemodynamically significant persistent ductus arteriosus (hsPDA) is made by a summary of non-uniform echo-criteria in combination with the clinical deterioration of the preterm neonate, standardized clinical and ultrasound scoring systems are needed. The objective of this study was the development of a clinical score for the detection and follow-up of hsPDA. In this observational cohort study of 154 preterm neonates (mean gestational age 28.1 weeks), clinical signs for the development of hsPDA were recorded in a standardized score and compared to echocardiography. Analyzing the significance of single score parameters compared to the diagnosis by echocardiography, we developed a short clinical score (calculated sensitivity 84% and specificity 80%). In conclusion, this clinical diagnostic PDA score is non-invasive and quickly to implement. The continuous assessment of defined clinical parameters allows for a more precise diagnosis of hemodynamic significance of PDA and, therefore, should help to detect preterm neonates needing PDA-treatment. The score, therefore, allows a more targeted use of echocardiography in these very fragile preterm neonates. PMID:29312911
PDA usage and training: targeting curriculum for residents and faculty.
Morris, Carl G; Church, Lili; Vincent, Chris; Rao, Ashwin
2007-06-01
Utilization of personal digital assistants (PDAs) in residency education is common, but information about their use and how residents are trained to use them is limited. Better understanding of resident and faculty PDA use and training is needed. We used a cross-sectional survey of 598 residents and faculty from the WWAMI (Washington, Wyoming, Alaska, Montana, and Idaho) Family Medicine Residency Network regarding PDA usage and training. Use of PDAs is common among residents (94%) and faculty (79%). Ninety-six percent of faculty and residents report stable or increasing frequency of use over time. The common barriers to PDA use relate to lack of time, knowledge, and formal education. Approximately half of PDA users (52%) have received some formal training; however, the majority of users report being self-taught. Faculty and residents prefer either small-group or one-on-one settings with hands-on, self-directed, interactive formats for PDA training. Large-group settings in lecture, written, or computer program formats were considered less helpful or desirable. PDAs have become a commonly used clinical tool. Lack of time and adequate training present a barrier to optimal application of PDAs in family medicine residency education.
Get Connected: An Approach to ResNet Services
ERIC Educational Resources Information Center
Workman, Sue; Childs, Melody; Causey, Jim; Moberly, Brent; Fitzpatrick, Christine
2006-01-01
At the beginning of an academic year, thousands of students move into campus housing on Indiana University's Bloomington and Indianapolis campuses within a three-day period, and more than 96 percent arrive with at least one personal computer (and possibly also a PDA, cell phone, and gaming system), and most expect to connect to the campus network…
Besmer, Dahlia M; Curry, Jennifer M; Roy, Lopamudra D; Tinder, Teresa L; Sahraei, Mahnaz; Schettini, Jorge; Hwang, Sun-Il; Lee, Yong Y; Gendler, Sandra J; Mukherjee, Pinku
2011-07-01
MUC1 is overexpressed and aberrantly glycosylated in more than 60% of pancreatic ductal adenocarcinomas. The functional role of MUC1 in pancreatic cancer has yet to be fully elucidated due to a dearth of appropriate models. In this study, we have generated mouse models that spontaneously develop pancreatic ductal adenocarcinoma (KC), which are either Muc1-null (KCKO) or express human MUC1 (KCM). We show that KCKO mice have significantly slower tumor progression and rates of secondary metastasis, compared with both KC and KCM. Cell lines derived from KCKO tumors have significantly less tumorigenic capacity compared with cells from KCM tumors. Therefore, mice with KCKO tumors had a significant survival benefit compared with mice with KCM tumors. In vitro, KCKO cells have reduced proliferation and invasion and failed to respond to epidermal growth factor, platelet-derived growth factor, or matrix metalloproteinase 9. Further, significantly less KCKO cells entered the G(2)-M phase of the cell cycle compared with the KCM cells. Proteomics and Western blotting analysis revealed a complete loss of cdc-25c expression, phosphorylation of mitogen-activated protein kinase (MAPK), as well as a significant decrease in nestin and tubulin-α2 chain expression in KCKO cells. Treatment with a MEK1/2 inhibitor, U0126, abrogated the enhanced proliferation of the KCM cells but had minimal effect on KCKO cells, suggesting that MUC1 is necessary for MAPK activity and oncogenic signaling. This is the first study to utilize a Muc1-null PDA mouse to fully elucidate the oncogenic role of MUC1, both in vivo and in vitro. ©2011 AACR
Zhang, Shengxiao; Zhang, Yuanyuan; Bi, Guoming; Liu, Junshen; Wang, Zhigang; Xu, Qiang; Xu, Hui; Li, Xiaoyan
2014-04-15
The polydopamine polymer decorated with magnetic nanoparticles (Fe3O4/PDA) was synthesized and applied for removal of multiple pollutants. The resulted Fe3O4/PDA was characterized with elemental analysis, thermo-gravimetric analyses, vibrating sample magnetometer, high resolution transmission electron microscope, Fourier transform infrared spectra, and X-ray photoelectron spectroscopy. The self-polymerization of dopamine could be completed within 8h, and Fe3O4 nanoparticles were embedded into PDA polymer. Superparamagnetism and large saturation magnetization facilitated collection of sorbents with a magnet. Based on the catechol and amine groups, the PDA polymer provided multiple interactions to combine with pollutants. To investigate the adsorption ability of Fe3O4/PDA, heavy metal ions and dyes were selected as target pollutants. The adsorption of pollutants was pH dependent due to the variation of surface charges at different solution pH. The removal efficiencies of cation pollutants enhanced with solution pH increasing, and that of anion pollutant was just the opposite. Under the optimal solution pH, the maximum adsorption capacity calculated from Langmuir adsorption isotherm for methylene blue, tartrazine, Cu(2+), Ag(+), and Hg(2+) were 204.1, 100.0, 112.9, 259.1, and 467.3 mg g(-1), respectively. The Fe3O4/PDA shows great potential for multiple pollutants removal, and this study is the first application of PDA polymer in environmental remediation. Copyright © 2014 Elsevier B.V. All rights reserved.
Hariu, Crystal D; Saunders, Ashley B; Gordon, Sonya G; Norby, Bo; Miller, Matthew W
2013-09-01
Determine if plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) correlates with markers of hemodynamically significant patent ductus arteriosus (PDA) in dogs. Ten dogs with PDA and 30 healthy dogs of similar ages. Prospective case series with control population. Dogs with PDA were initially evaluated with thoracic radiographs, transthoracic echocardiography, pulmonary capillary wedge pressure (PCWP) and NT-proBNP. Following ductal occlusion, NT-proBNP and echocardiography were repeated within 24 h and at day 90. PCWP was repeated at day 90. Correlation between NT-proBNP and hemodynamic measurements was assessed, and accuracy of NT-proBNP for identifying PDA severity was estimated. NT-proBNP was significantly higher (median; absolute range) in dogs with PDA (895; 490-7118 pmol/L) than controls (663; 50-1318 pmol/L) (p = 0.025). NT-proBNP decreased significantly 90 days post-ductal closure (597; 154-1858 pmol/L) (p = 0.013). Left atrial and ventricular size decreased significantly within 24 h and at day 90 as did PCWP (day 90 only). NT-proBNP correlated with vertebral heart size (VHS) and indexed left ventricular systolic diameter (iLVIDs); concentrations ≥ 1224 pmol/L distinguished dogs with elevated VHS and iLVIDs. NT-proBNP is elevated in dogs with PDA, decreases following PDA closure and correlates with select radiographic and echocardiographic markers of cardiac remodeling. Copyright © 2013 Elsevier B.V. All rights reserved.
Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin
2017-01-01
Background To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Methods Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Results Pharmacological closures were attempted at postnatal day 2–3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . Conclusion We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function. PMID:29333220
Vocal cord paralysis post patent ductus arteriosus ligation surgery: risks and co-morbidities.
Rukholm, Gavin; Farrokhyar, Forough; Reid, Diane
2012-11-01
1. To determine the prevalence of left vocal cord paralysis (LVCP) post patent ductus arteriosus (PDA) ligation at a Tertiary Care Centre. 2. To identify risk factors associated with LVCP. 3. To identify co-morbidities associated with LVCP. 4. To determine the frequency of pre- and post-operative nasopharyngolaryngoscopic (NPL) examination in this patient population. Retrospective chart review of all infants who underwent PDA ligation surgery at a tertiary care academic hospital between July 2003 and July 2010. Data on patient age, gender, weight, method of PDA ligation, and results of NPL scoping were collected, as well as patient co-morbidities post PDA ligation. One hundred and fifteen patients underwent PDA ligation surgery. Four patients were excluded due to bilateral vocal cord paralysis. Of the remaining 111 patients, nineteen patients (17.1%) were found to have LVCP. Low birth weight was identified as a significant risk factor for LVCP (p=0.002). Gastroesophageal reflux was identified as a significant co-morbidity associated with LVCP post PDA ligation (p=0.002). Only 0.9% of patients were scoped pre-operatively, and 27.9% were scoped postoperatively. LVCP is associated with multiple morbidities. The authors strongly recommend routine post-operative scoping of all patients post PDA ligation surgery, and preoperative scoping when possible. A prospective study is warranted, in order to confirm the prevalence of LVCP as well as risk factors and associated co-morbidities. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.
Pacifici, Gian Maria
2014-01-01
Ibuprofen and indomethacin are potent non-selective cyclo-oxygenase inhibitors and inhibit prostaglandin E2 synthesis. The patent ductus arteriosus (PDA) occurs in more than 70% of preterm infants weighing <1500 g. Prostaglandin E2 relaxes smooth muscle, tends to inhibit the closure of PDA, yields vasodilatation of the afferent renal arterioles and maintains glomerular filtration rate (GFR). Ibuprofen and indomethacin inhibiting prostaglandin E2 synthesis close PDA and reduce GFR with consequent decrease of urine output and increase of serum creatinine concentrations. The aims of this study are to give the definitive estimates of PDA closure rate following ibuprofen or indomethacin treatment and to evaluate the extent of renal side effects following the administration of these drugs to preterm infants. Other aims are to review the metabolism and the pharmacokinetics of ibuprofen and indomethacin in preterm infants with PDA. The bibliographic search was performed using PubMed and EMBASE databases as search engines, January 2013 was the cutoff point. The %PDA closed by ibuprofen (n=24) and indomethacin (n=24) is 77.7±14.1 and 77.3±11.0, respectively. For ibuprofen, the gestational age of the infants included in the study ranged from 25.0 to 39.0 weeks (mean±SD=29.3±3.1 weeks). The %PDA did not correlate with the gestational age (p=0.2516). For indomethacin, the gestational age of infants included in the study ranged from 25.0 and 39.0 weeks (mean±SD=29.4±2.9 weeks). The %PDA did not correlate with the gestational age (p=0.3742). The treatment with ibuprofen reduces the urine output and increases the serum creatinine concentrations less extensively than indomethacin. The half-life (t1/2) of ibuprofen and indomethacin is lengthened and the clearance is reduced in preterm infants as compared with fullterm infants. Ibuprofen and indomethacin are equally effective in closing PDA. Treatment with ibuprofen decreases the risk of renal failure. Ibuprofen has the most favourable risk/benefit ratio. The rate of metabolism is reduced and t1/2 is lengthened in prematures as compared with term infants.
Bailey, Robert A; Shillington, Alicia C; Harshaw, Qing; Funnell, Martha M; VanWingen, Jeffrey; Col, Nananda
2018-04-01
Failure to intensify treatment for type 2 diabetes mellitus (T2DM) when indicated, or clinical inertia, is a major obstacle to achieving optimal glucose control. This study investigates the impact of a values-focused patient decision aid (PDA) for T2DM antihyperglycemic agent intensification on patient values related to domains important in decision-making and preferred treatments. Patients with poorly controlled T2DM who were taking a metformin-containing regimen were recruited through physicians to access a PDA presenting evidence-based information on T2DM and antihyperglycemic agent class options. Participants' preferences for treatment, decision-making, and the relative importance they placed on various values related to treatment options (e.g., dosing, weight gain, side effects) were assessed before and after interacting with the PDA. Changes from baseline were calculated (post-PDA minus pre-PDA difference) and assessed in univariate generalized linear models exploring associations with patients' personal values. Analyses included 114 diverse patients from 27 clinics across the US. The importance of avoiding injections, concern about hypoglycemia, and taking medications only once a day significantly decreased after interacting with the PDA [- 1.1 (p = 0.002), - 1.3 (p < 0.001), - 1.1 (p = 0.004), respectively], while the importance of taking medications that avoided weight gain increased [0.8 (p = 0.004)]. Prior to viewing the PDA, most patients (58.8%) had not begun thinking about the decision of adding a medication, and few (12.3%) indicated that they had already made a decision. Post-PDA, 46.5% could state a medication preference. The values-focused PDA for T2DM medication intensification prepared patients to make a shared decision with their clinician and changed patients' values regarding what was important in making that decision. Helping patients understand their options and underlying values can promote shared decision-making and may reduce clinical inertia delaying treatment intensification. Janssen Scientific Affairs, LLC.
The Mechanisms and Effects of the Plant Activation of Chemicals in the Environment
1991-12-02
amino- Uilich et al., 1973; Raz- fluorene-N-hydroxylase. zouk et al., 1980 * Did not inhibit the TXI cell activation of m-PDA, howev- Wagner et al...P450 in mammals and Goujon et al., 1972, Car- yeast. Inhibited 2-AF hydroxylase. ratore et al., 1986; Raz- zouk et al., 1980 i Did not inhibit the TXI...Activation of 2-aminofluorene by cultured plant cells. Science 219:1427-1429 Poulsen LL, R.M. Hyslop , D.M. Ziegler. 1974. S-oxidation of
Sanal, Bekir; Nas, Omer Fatih; Hacikurt, Kadir; Hakyemez, Bahattin; Erdogan, Cuneyt
2016-02-01
True aneurysm of pancreaticoduodenal arcade (PDA) is usually accompanied by stenosis or occlusion of celiac trunk (CeT). The up-to-date and first choice treatment modality of PDA aneurysm is the endovascular approach in nearly all cases except few selected ones necessitating surgery. The main approach in endovascular treatment is embolization of the aneurysm by preserving the parent artery. A case with concomitant CeT occlusion and PDA aneurysm was treated with coil embolization by preserving inferior pancreaticoduodenal artery with retrievable Solitaire(®) stent. In our knowledge, this is the first case with PDA aneurysm treated with this technique. © The Author(s) 2016.
Future Force Warrior: Insights from Air Assault Expeditionary Force Assessment
2007-07-01
your bearing and distance to the target instead of walking along a line. 1 Change the goggles’ pattern. 1 Get rid of the goggles and instead use...weapon. 1 Get my eyes corrected with laser; this system is not for Soldiers with glasses. 1 Get rid of the goggles and have live up-to-date bearing...10 hrs/ PDA stand alone 8 hrs. 1 5. How long does it take to get the radios functional at the beginning of each day and what are the problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jo, Kwang-Won; Cho, Won-Ju, E-mail: chowj@kw.ac.kr
In this study, we evaluated the effects of microwave irradiation (MWI) post-deposition-annealing (PDA) treatment on the gate bias stress instability of amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) and compared the results with a conventional thermal annealing PDA treatment. The MWI-PDA-treated a-IGZO TFTs exhibited enhanced electrical performance as well as improved long-term stability with increasing microwave power. The positive turn-on voltage shift (ΔV{sub ON}) as a function of stress time with positive bias and varying temperature was precisely modeled on a stretched-exponential equation, suggesting that charge trapping is a dominant mechanism in the instability of MWI-PDA-treated a-IGZO TFTs. The characteristicmore » trapping time and average effective barrier height for electron transport indicate that the MWI-PDA treatment effectively reduces the defects in a-IGZO TFTs, resulting in a superior resistance against gate bias stress.« less
NASA Astrophysics Data System (ADS)
Toma, Mana; Tawa, Keiko
2018-03-01
A bioinspired polydopamine (PDA) coating is a good candidate for the rapid and cheap chemical modification of biosensor surfaces. Herein, we report the effect of PDA thickness on the detection sensitivity of a fluorescence biosensor utilizing surface plasmon-enhanced fluorescence. The thickness of PDA films was tuned by the incubation time of the dopamine solution and varied from 1 to 17 nm. The detection sensitivity was evaluated as the limit of detection (LOD) of a fluorescently labelled target analyte by a model immunoassay. The LOD was determined to be 1.6 pM for the thickest PDA film and was improved to 1.0 pM by reducing the thickness to the range from 1 to 5 nm, corresponding to the incubation time of 10 to 60 min. The experimental results indicate that the PDA coating is suitable for the surface functionalization of biosensors in mass production as it does not require precise control of the incubation time.
Wang, Liwei; Huang, Xingyi; Zhu, Yingke; Jiang, Pingkai
2018-02-14
Introducing a high dielectric constant (high-k) nanofiller into a dielectric polymer is the most common way to achieve flexible nanocomposites for electrostatic energy storage devices. However, the significant decrease of breakdown strength and large increase of dielectric loss has long been known as the bottleneck restricting the enhancement of practical energy storage capability of the nanocomposites. In this study, by introducing ultra-small platinum (<2 nm) nanoparticles, high-k polymer nanocomposites with high breakdown strength and low dielectric loss were prepared successfully. Core-shell structured polydopamine@BaTiO 3 (PDA@BT) and core-satellite ultra-small platinum decorated PDA@BT (Pt@PDA@BT) were used as nanofillers. Compared with PDA@BT nanocomposites, the maximum discharged energy density of the Pt@PDA@BT nanocomposites is increased by nearly 70% because of the improved energy storage efficiency. This research provides a simple, promising and unique way to enhance energy storage capability of high-k polymer nanocomposites.
NASA Astrophysics Data System (ADS)
Zhu, Kairuo; Lu, Songhua; Gao, Yang; Zhang, Rui; Tan, Xiaoli; Chen, Changlun
2017-02-01
Novel hierarchical core/shell structured polydopamine@MgAl-layered double hydroxides (PDA@MgAl-LDHs) composites involving MgAl-layered double hydroxide shells and PDA cores were fabricated thought one-pot coprecipitation assembly and methodically characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, scanning/transmission electron microscopy, selected area electron diffraction, elemental mapping, thermogravimetric analysis and X-ray photoelectron spectroscopy technologies. U(VI) and Eu(III) sorption experiments showed that the PDA@MgAl-LDHs exhibited higher sorption ability with a maximum sorption capacity of 142.86 and 76.02 mg/g at 298 K and pH 4.5, respectively. More importantly, according to XPS analyses, U(VI) and Eu(III) were sorbed on PDA@MgAl-LDHs via oxygen-containing functional groups, and the chemical affinity of U(VI) by oxygen-containing functional groups is higher than that of Eu(III). These observations show great expectations in the enrichment of radionuclides from aquatic environments by PDA@MgAl-LDHs.
Patent ductus arteriosus in a family of Chihuahuas.
Bomassi, E; Libermann, S; Bille, C; Rattez, E
2011-04-01
This report describes a patent ductus arteriosus (PDA) in four puppies from the same family of Chihuahuas, bred from the same mother and from two different litters. Identification of this congenital anomaly relies on clinical examination, radiography and ultrasonography. Three of these puppies were female, and had a type-1 PDA. A conventional surgical ligation was performed on one of them, whilst the others underwent no treatment. One puppy was male, and presented with a type-4 PDA, requiring euthanasia. Post-mortem examination and histopathological examination of the PDA allowed characterisation of the histological anomalies, which were identical to those described in other breeds. The mother and the two stud dogs were not affected. Even though the mode of transmission has not been fully identified, it is evident that this PDA is hereditary in nature. To the authors' knowledge this is the first description of this congenital cardiopathy in a family of this breed, and in a significant number of first-generation individuals. © 2011 British Small Animal Veterinary Association.
Kolusheva, S; Yossef, R; Kugel, A; Katz, M; Volinsky, R; Welt, M; Hadad, U; Drory, V; Kliger, M; Rubin, E; Porgador, A; Jelinek, R
2012-07-17
We demonstrate a novel array-based diagnostic platform comprising lipid/polydiacetylene (PDA) vesicles embedded within a transparent silica-gel matrix. The diagnostic scheme is based upon the unique chromatic properties of PDA, which undergoes blue-red transformations induced by interactions with amphiphilic or membrane-active analytes. We show that constructing a gel matrix array hosting PDA vesicles with different lipid compositions and applying to blood plasma obtained from healthy individuals and from patients suffering from disease, respectively, allow distinguishing among the disease conditions through application of a simple machine-learning algorithm, using the colorimetric response of the lipid/PDA/gel matrix as the input. Importantly, the new colorimetric diagnostic approach does not require a priori knowledge on the exact metabolite compositions of the blood plasma, since the concept relies only on identifying statistically significant changes in overall disease-induced chromatic response. The chromatic lipid/PDA/gel array-based "fingerprinting" concept is generic, easy to apply, and could be implemented for varied diagnostic and screening applications.
Catheter-based closure of the patent ductus arteriosus in lower weight infants.
Pavlek, Leeann R; Slaughter, Jonathan L; Berman, Darren P; Backes, Carl H
2018-06-13
Risks associated with drug therapy and surgical ligation have led health care providers to consider alternative strategies for patent ductus arteriosus (PDA) closure. Catheter-based PDA closure is the procedure of choice for ductal closure in adults, children, and infants ≥6kg. Given evidence among older counterparts, interest in catheter-based closure of the PDA in lower weight (<6kg) infants is growing. Among these smaller infants, the goals of this review are to: (1) provide an overview of the procedure; (2) review the types of PDA closure devices; (3) review the technical success (feasibility); (4) review the risks (safety profile); (5) discuss the quality of evidence on procedural efficacy; (6) consider areas for future research. The review provided herein suggests that catheter-based PDA closure is technically feasible, but the lack of comparative trials precludes determination of the optimal strategy for ductal closure in this subgroup of infants. Copyright © 2018 Elsevier Inc. All rights reserved.
Dopamine-assisted co-deposition: An emerging and promising strategy for surface modification.
Qiu, Wen-Ze; Yang, Hao-Cheng; Xu, Zhi-Kang
2018-04-27
Mussel-inspired chemistry based on polydopamine (PDA) deposition has been developed as a facile and universal method for the surface modification of various materials. However, the inherent shortcomings of PDA coatings still impede their practical applications in the development of functional materials. In this review, we introduce the recent progress in the emerging dopamine-assisted co-deposition as a one-step strategy for functionalizing PDA-based coatings, and improving them in the aspects of deposition rate, morphology uniformity, surface wettability and chemical stability. The co-deposition mechanisms are categorized and discussed according to the interactions of dopamine or PDA with the introduced co-component. We also emphasize the influence of these interactions on the properties of the resultant PDA-based coatings. Meanwhile, we conclude the representative potential applications of those dopamine-assisted co-deposited coatings in material science, especially including separation membranes and biomaterials. Finally, some important issues and perspectives for theoretical study and applications are briefly discussed. Copyright © 2017 Elsevier B.V. All rights reserved.
Back to the future: personal digital assistants in nursing education.
McLeod, Renee P; Mays, Mary Z
2008-12-01
This article provides an overview of the current state of the art for incorporating personal digital assistants (PDAs) into nursing education. The development of PDA technology and the lessons learned by educators integrating PDA technology into nursing curricula are described. The current cycle of PDA evolution is discussed and contrasted with a proposed model for maximizing the impact of PDAs on technological innovation in nursing education and practice.
Determining position inside building via laser rangefinder and handheld computer
Ramsey, Jr James L. [Albuquerque, NM; Finley, Patrick [Albuquerque, NM; Melton, Brad [Albuquerque, NM
2010-01-12
An apparatus, computer software, and a method of determining position inside a building comprising selecting on a PDA at least two walls of a room in a digitized map of a building or a portion of a building, pointing and firing a laser rangefinder at corresponding physical walls, transmitting collected range information to the PDA, and computing on the PDA a position of the laser rangefinder within the room.
NASA Astrophysics Data System (ADS)
Deng, Yuanfu; Xu, Hui; Bai, Zhaowen; Huang, Baoling; Su, Jingyang; Chen, Guohua
2015-12-01
Lithium-sulfur batteries show fascinating potential for advanced energy system due to their high specific capacity, low-cost, and environmental benignity. However, their wide applications have been plagued by low coulombic efficiency, fast capacity fading and poor rate performance. Herein, a facile method for preparation of S@PDA (PDA = polydopamine) composites with core-shell structure and good electrochemical performance as well as the First-Principles calculations on the interactions of PDA and polysulfides are reported. Taking the advantages of the core-shell structure with porous sulfur core, the high mechanical flexibility of PDA for accommodating the volumetric variation during the discharge/charge processes, the good lithium ion conductivity and the strong chemical interactions between the nitrogen/oxygen atoms with lone electron pair and lithium polysulfides for alleviating their dissolution, the S@PDA composites exhibit high discharge capacities at different current densities (1048 and 869 mAh g-1 at 0.2 and 0.8 A g-1, respectively) and excellent capacity retention capability. A capacity decay as low as 0.021% per cycle and an average coulombic efficiency of 98.5% is observed over a long-term cycling of 890 cycles at 0.8 A g-1. The S@PDA electrode has great potential as a low-cost cathode in high energy Li-S batteries.
Badawi, Hassan M; Förner, Wolfgang; Ali, Shaikh A
2013-08-01
The structural stabilities of o-, m- and p-phenylenediamine (PDA) isomers were investigated by DFT-B3LYP and ab initio MP2 calculations with the 6-311G(**) basis set. From the calculations the three isomers were predicted to exist predominantly in an anti (transoid) structure. In the o-isomer, the syn (cisoid) form is calculated to turn to the anti (transoid) form with the two HNCC torsional angles of about 44 and 10° and the NH2 inversion barrier of 3-4 kcal/mol. The CCNH torsional angles in the m-PDA and p-PDA isomers were calculated to be about 25-26° as compared to 20° in aniline. A comparison of the Raman spectra of the three PDA-s with those of aniline shows the high sensitivity of the ring breathing mode to the nature of substituents in the aniline ring. The vibrational wavenumbers were computed at the DFT-B3LYP for aniline and the o-, m- and p-PDA isomers for the purpose of comparison. Complete vibrational assignments were made on the basis of normal coordinate analyses and potential energy distributions for aniline and the o-, m- and p-PDA molecules. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Xu, Xiaohui; Bai, Bo; Wang, Honglun; Suo, Yourui
2015-12-01
Polydopamine coated sea buckthorn branch powder (PDA@SBP) was facilely synthesized via a one-pot bio-inspired dip-coating approach. The as-synthesized PDA@SBP was characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The adsorption progresses of Safranine T on the surface of PDA@SBP adsorbent were systematically investigated. More specifically, the effects of solution pH, contact time, initial concentration and temperature were evaluated, respectively. The experimental results showed the adsorption capacity of PDA@SBP at 293.15 K could reach up to 54.0 mg/g; the adsorption increased by 201.7% compared to that of native SBP (17.9 mg/g). Besides, kinetics studies showed that pseudo-second-order kinetic model adequately described the adsorption behavior. The adsorption experimental data could be fitted well a Freundlich isotherm model. Thermodynamic analyses showed that the ST adsorption was a physisorption endothermic process. Regeneration of the spent PDA@SBP adsorbent was conducted with 0.1 M HCl without significant reduction in adsorption capacity. On the basis of these investigations, it is believed that the PDA@SBP adsorbent could have potential applications in sewage disposal areas because of their considerable adsorption capacities, brilliant regeneration capability, and cost-effective and eco-friendly preparation and use.
Radiology on handheld devices: image display, manipulation, and PACS integration issues.
Raman, Bhargav; Raman, Raghav; Raman, Lalithakala; Beaulieu, Christopher F
2004-01-01
Handheld personal digital assistants (PDAs) have undergone continuous and substantial improvements in hardware and graphics capabilities, making them a compelling platform for novel developments in teleradiology. The latest PDAs have processor speeds of up to 400 MHz and storage capacities of up to 80 Gbytes with memory expansion methods. A Digital Imaging and Communications in Medicine (DICOM)-compliant, vendor-independent handheld image access system was developed in which a PDA server acts as the gateway between a picture archiving and communication system (PACS) and PDAs. The system is compatible with most currently available PDA models. It is capable of both wired and wireless transfer of images and includes custom PDA software and World Wide Web interfaces that implement a variety of basic image manipulation functions. Implementation of this system, which is currently undergoing debugging and beta testing, required optimization of the user interface to efficiently display images on smaller PDA screens. The PDA server manages user work lists and implements compression and security features to accelerate transfer speeds, protect patient information, and regulate access. Although some limitations remain, PDA-based teleradiology has the potential to increase the efficiency of the radiologic work flow, increasing productivity and improving communication with referring physicians and patients. Copyright RSNA, 2004
NASA Astrophysics Data System (ADS)
Zhang, Meili; Ren, Yixia; Ma, Zhenzhen; Qiao, Lei
2017-06-01
Two coordination polymers, [Zn(pda)(bib)]n (1) and [Cd(pda)0.5(bib)Cl]n (2)]. (H2pda = 1,4-phenylenediacetic acid, bib = 1,2-bis(imidazol-1-ylmethyl)benzene), have been synthesized by using Zn(II)/Cd(II) salts with two flexible ligands pda and bib under hydrothermal conditions. Their structures have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray crystallography and powder X-ray diffraction (PXRD) analysis. Due to the coordination geometry around the metal ions and the diverse coordination modes of the flexible ligands, the obtained complex show diverse structures. In the structure of 1, a pair of bib ligands connect two Zn(II) atoms give rise a 22-membered ring, which is further extended by pda ligands in bidentate coordination mode leading a ring-containing 2D layer. In 2, bib ligands join [Cd2Cl2]2+ dimmers generate 1D polymeric ribbon, the pda ligands further extend such ribbon forming a 2D layer network containing rectangular windows, which discovers the effect of the central metal ions on the formation of metal-organic frameworks. In additional, luminescent properties of two complexes have also been studied, they could be potential fluorescence materials.
Tsui, Irena; Ebani, Edward; Rosenberg, Jamie B; Lin, Juan; Angert, Robert M; Mian, Umar
2013-01-01
To examine whether clinically significant patent ductus arteriosus (PDA) or indomethacin treatment are associated with plus disease or retinopathy of prematurity (ROP) requiring treatment. Retrospective, cross-sectional study. Charts were reviewed for gestational age, birth weight, birth head circumference, birth length, maternal characteristics, gender, bronchopulmonary dysplasia, neurologic comorbidities, PDA and its treatments, gastrointestinal comorbidities, blood transfusions, and sepsis. Main outcome measures were increased rates of plus disease or ROP requiring treatment. A total of 450 premature infants screened for ROP in a mid-sized, urban neonatal intensive care unit were included. On univariate analysis, gestational age, birth weight, birth head circumference, birth length, bronchopulmonary dysplasia, neurologic comorbidities, PDA and its treatments, gastrointestinal comorbidities, and sepsis were significantly correlated to plus disease and ROP requiring treatment. PDA was significantly associated with bronchopulmonary dysplasia, neurologic comorbidities, sepsis, and blood transfusions (P < .0001). With type 3 multivariate analysis, only gestational age and bronchopulmonary dysplasia were independent risk factors for ROP. PDA and indomethacin were associated with plus disease and ROP requiring treatment on univariate analysis but this was not significant after adjusting for other risk factors. PDA was also strongly related to bronchopulmonary dysplasia and blood transfusions, which may explain its effect on ROP. Copyright 2013, SLACK Incorporated.
Rudaz, Myriam; Craske, Michelle G; Becker, Eni S; Ledermann, Thomas; Margraf, Jürgen
2010-04-01
This study is aimed to evaluate the role of two vulnerability factors, health anxiety and fear of fear, in the prediction of the onset of panic disorder/agoraphobia (PDA) relative to a comparison anxiety disorder. Young women, aged between 18 and 24 years, were investigated at baseline and, 17 months later, using the Anxiety Disorders Interview Schedule-Lifetime and measures of health anxiety and fear of bodily sensations (subscale disease phobia of the Whiteley Index, and total score of the Body Sensations Questionnaire). First, 22 women with current PDA were compared to 81 women with current social phobia and 1,283 controls. Second, 24 women with an incidence of PDA were compared to 60 women with an incidence of social phobia and 1,036 controls. Multiple logistic regression analyses adjusted for history of physical diseases, somatic symptoms, and other psychological disorders revealed that (a) fear of bodily sensations was elevated for women with PDA vs. controls as well as women with social phobia, and (b) health anxiety (and history of physical diseases) was elevated in women who developed PDA vs. controls and vs. women who developed social phobia. These results suggest that health anxiety, as well as history of physical diseases, may be specific vulnerability factors for the onset of PDA relative to social phobia. Whereas fear of bodily sensations was not found to be a risk factor for the onset of panic disorder/agoraphobia, it was a specific marker of existing PDA relative to social phobia. Copyright 2010 Wiley-Liss, Inc.
Effect of surgical subspecialty training on patent ductus arteriosus ligation outcomes.
Markush, Dor; Briden, Kelleigh E; Chung, Michael; Herbst, Katherine W; Lerer, Trudy J; Neff, Stephen; Wu, Amy C; Campbell, Brendan T
2014-05-01
Surgical outcomes data for patent ductus arteriosus (PDA) ligation come primarily from single institution case series. The purpose of this study was to evaluate national PDA ligation trends, and to compare outcomes between pediatric general (GEN) and pediatric cardiothoracic (CT) surgeons. The Pediatric Health Information System database was queried to identify neonates who underwent PDA ligation from 2006 through 2009. Outcomes evaluated included surgical morbidity, in-hospital mortality, length of stay, and total charges. Outcomes were compared between pediatric general and pediatric cardiothoracic surgeons. The records of 1,482 neonates who underwent PDA ligation were identified and analyzed. Overall mean gestational age was 26 ± 3 weeks and birth weight was 888 ± 428 g. The majority of patients among both surgeons had birth weights of ≤1,000 g (77.2%) and were born at ≤27-week gestation (81.5%). Most of the PDA ligations were performed by pediatric CT surgeons (n = 1,196, 80.7%). The mortality rate did not differ by surgeon subspecialty training (GEN = 5.2%, CT 7.9%, p = 0.16). Neonates in the cardiothoracic surgeon cohort showed lower length of stay (p < 0.001-0.05) and total hospital charges (p < 0.05) among patients with birth weight ≤1,200 g. Proxy measures of surgical morbidity-gastrostomy, fundoplication, and tracheostomy-showed no significant differences between the two surgical subspecialists overall or across birth weight subgroups (p > 0.05). These data provide a contemporary snapshot of PDA ligation outcomes at American children's hospitals. Pediatric general surgeons achieve comparable outcomes performing PDA ligation compared to pediatric cardiothoracic surgeons.
Zhou, Fei; Zhao, Yajing; Peng, Jiyu; Jiang, Yirong; Li, Maiquan; Jiang, Yuan; Lu, Baiyi
2017-07-01
Osmanthus fragrans flowers are used as folk medicine and additives for teas, beverages and foods. The metabolites of O. fragrans flowers from different geographical origins were inconsistent in some extent. Chromatography and mass spectrometry combined with multivariable analysis methods provides an approach for discriminating the origin of O. fragrans flowers. To discriminate the Osmanthus fragrans var. thunbergii flowers from different origins with the identified metabolites. GC-MS and UPLC-PDA were conducted to analyse the metabolites in O. fragrans var. thunbergii flowers (in total 150 samples). Principal component analysis (PCA), soft independent modelling of class analogy analysis (SIMCA) and random forest (RF) analysis were applied to group the GC-MS and UPLC-PDA data. GC-MS identified 32 compounds common to all samples while UPLC-PDA/QTOF-MS identified 16 common compounds. PCA of the UPLC-PDA data generated a better clustering than PCA of the GC-MS data. Ten metabolites (six from GC-MS and four from UPLC-PDA) were selected as effective compounds for discrimination by PCA loadings. SIMCA and RF analysis were used to build classification models, and the RF model, based on the four effective compounds (caffeic acid derivative, acteoside, ligustroside and compound 15), yielded better results with the classification rate of 100% in the calibration set and 97.8% in the prediction set. GC-MS and UPLC-PDA combined with multivariable analysis methods can discriminate the origin of Osmanthus fragrans var. thunbergii flowers. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Lee, Ping Yein; Khoo, Ee Ming; Low, Wah Yun; Lee, Yew Kong; Abdullah, Khatijah Lim; Azmi, Syahidatul Akmal; Ng, Chirk Jenn
2016-04-01
Malaysia is an Asian country with population of diverse culture and health perceptions. Patient decision aid (PDA) is a new tool in Malaysia. Patients' and health-care professionals' (HCPs) expectation of a PDA is unknown. We aimed to explore patients' and health-care professionals'(HCPs) views on the information needed in a patient decision aid (PDA) on insulin initiation developed for patients with type 2 diabetes mellitus (T2DM). We used a qualitative design and thematic approach. Three main primary health-care settings in Malaysia: public university-based primary care clinics, public health-care clinics and private general practices. We conducted focus groups and one-to-one interviews with a purposive sample of health professionals and patients with type 2 diabetes. We interviewed 18 patients and 13 HCPs. Patients viewed the content of the PDA as simple and clear. However, HCPs felt the PDA might be difficult for patients with low literacy to understand. HCPs thought the PDA was too lengthy. Nevertheless, patients would prefer more information. HCPs tended to focus on benefits of insulin, while patients wanted to know the impact of insulin on their quality of life and practical issues regarding insulin and its side-effects. Patients preferred numbers to weigh the risks and benefits of treatment options. HCPs' views that presenting numbers in a PDA would be too complex for patients to understand. It is important to consider including issues related to psycho-social impact of treatment to patients when developing a patient decision aid. © 2015 John Wiley & Sons Ltd.
Trans-pulmonary echocardiography as a guide for device closure of patent ductus arteriosus.
Kudo, Yoshiyuki; Suda, Kenji; Yoshimoto, Hironaga; Teramachi, Yozo; Kishimoto, Shintaro; Iemura, Motofumi; Matsuishi, Toyojiro
2015-08-01
The aim of this study was to develop trans-pulmonary echocardiography (TPE) to guide device closure of patent ductus arteriosus (DC-PDA). Aortography requires a large amount of contrast yet may give us an inadequate image to evaluate anatomy or residual shunt in patients with large PDA or dilated vessels and is precluded in patients with renal dysfunction. Practically, there is no imaging modality to monitor the entire procedure except for trans-esophageal echocardiography that requires general anesthesia. Subjects were seven patients with ages ranged from 6- to 77-years old and body weight > 15 kg. The size of the PDA ranged from 1.8 to 6.3 mm with pulmonary to systemic flow ratios from 1.2 to 2.2. During DC-PDA using Ampaltzer Duct Occluder or coil, an intra-cardiac echocardiographic (ICE) catheter was advanced into pulmonary arteries and standard views were developed to guide DC-PDA. We have developed two standard views; the main pulmonary artery view (MPA view) and the left pulmonary artery view (LPA view). The MPA view provided aortic short axis view equivalent to that seen by trans-thoracic echocardiography in children. The LPA view, obtained by the echo probe in the LPA and turned it up upside down, provided long axis view of the PDA allowing more precise anatomical evaluation. TPE allowed us to monitor the entire procedure and determine residual shunts. TPE in the MPA and LPA view can be an effective guide for DC-PDA. This report leads to new application of this imaging device. © 2015 Wiley Periodicals, Inc.
Spontaneous Closure of Patent Ductus Arteriosus in Infants ≤1500 g.
Semberova, Jana; Sirc, Jan; Miletin, Jan; Kucera, Jachym; Berka, Ivan; Sebkova, Sylva; O'Sullivan, Sinead; Franklin, Orla; Stranak, Zbynek
2017-08-01
Patent ductus arteriosus (PDA) remains a challenging issue in very low birth weight (VLBW) infants, and its management varies widely. Our aim in this study was to document the natural course of ductus arteriosus in a cohort of VLBW infants who underwent conservative PDA management with no medical or surgical intervention. A retrospective cohort study conducted in 2 European level-3 neonatal units. A total of 368 VLBW infants were born within the study period. Two hundred and ninety-seven infants were free of congenital malformations or heart defects and survived to hospital discharge. Out of those, 280 infants received truly conservative PDA management. In 237 (85%) of nontreated infants, the PDA closed before hospital discharge. The Kaplan-Meier model was used to document the incidence proportion of PDA closure over time for different gestational age groups. The median time to ductal closure was 71, 13, 8, and 6 days in <26+0, 26+0 to 27+6, 28+0 to 29+6, and ≥30 weeks, respectively. For different birth weight groups, the median was 48, 22, 9, and 8 days in infants weighing <750, 750 to 999, 1000 to 1249, and 1250 to 1500 g, respectively. No statistically significant relationship was found between PDA closure before hospital discharge and neonatal morbidities. The likelihood of PDA spontaneous closure in VLBW infants is extremely high. We provide in our findings a platform for future placebo-controlled trials focused on the smallest and youngest infants. Copyright © 2017 by the American Academy of Pediatrics.
Moore, John W; Greene, Jessica; Palomares, Salvadore; Javois, Alexander; Owada, Carl Y; Cheatham, John P; Hoyer, Mark H; Jones, Thomas K; Levi, Daniel S
2014-12-01
This study aimed to compare the efficacy and safety of the Nit-Occlud PDA device (PFM Medical, Cologne, Germany) to benchmarks designed as objective performance criteria (OPC). The Nit-Occlud PDA is a nitinol coil-type patent ductus arteriosus (PDA) occluder with a reverse cone configuration, which is implanted using a controlled delivery system. Patients with <4-mm minimum diameter PDA were prospectively enrolled in the Pivotal and the Continuing Access Studies from 15 sites in the United States and were followed up for 12 months post-procedure. Investigator-reported outcomes were compared to OPC including a composite success criterion, efficacy criteria of successful closure (clinical and echocardiographic), and safety criteria incidence of adverse events (serious and of total). The Pivotal Study enrolled patients between November 1, 2002 and October 31, 2005, and the Continuing Access Study enrolled additional patients between September 1, 2006 and October 31, 2007. A total of 357 patients were enrolled, and 347 had successful device implantations. After 12 months, 96.8% had complete echocardiographic closure (OPC = 85%) and 98.1% had clinical closure (OPC = 95%). There were no deaths or serious adverse events (OPC = 1%). The total adverse event rate was 4.7% (OPC = 6%). Composite success was 95.1% in the study patients (OPC = 80%). Closure of small- and medium-sized PDA with the Nit-Occlud PDA is effective and safe when compared with OPC. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Long-term follow-up after transvenous single coil embolization of patent ductus arteriosus in dogs.
Hildebrandt, N; Schneider, C; Schweigl, T; Schneider, M
2010-01-01
Long-term follow-up studies after interventional therapy of patent ductus arteriosus (PDA) in dogs are rare. Transvenous PDA embolization with a single detachable coil is a highly effective method in patients with an angiographically determined PDA≤4.0 mm. Twenty-eight dogs with an angiographic PDA≤4.0 mm were included. Prospective follow-up study after PDA coil embolization. The median follow-up time was 792 days (range, 2-3, 248 days). The rate of complete closure demonstrated by Doppler color flow was 54% at day 3 after intervention and the final cumulative rate was 71%. The rate of complete closure was significantly different between small and moderately sized PDA over the study period (P<.0001) and finally was 100 and 50%, respectively. In 16 dogs with complete closure, no recanalization was found. Disappearance of the continuous heart murmur was found in 89% after 3 days, and this increased to a final cumulative rate of 96%. Indexed left ventricular internal diameter in diastole (LVDd-I) decreased significantly (P<.0001). In the group with moderately sized PDA, a significant difference (P=.0256) was seen in LVDd-I between patients with and without residual shunt after exclusion of patients with persistent severe mitral valve regurgitation. Long-term follow-up after single coil embolization showed complete closure in all small PDA but a residual shunt with mild hemodynamic consequences was present in half of the moderately sized PDA. Copyright © 2010 by the American College of Veterinary Internal Medicine.
Techniques for trans-catheter retrieval of embolized Nit-Occlud® PDA-R and ASD-R devices.
Sinha, Sanjay; Levi, Daniel; Peirone, Alejandro; Pedra, Carlos
2018-02-15
Nit-Occlud ® (atrial septal defect) ASD-R and (patent ductus arteriosus) PDA-R devices are used outside the United States for percutaneous closure of the patent ductus arteriosus and atrial septal defects. When embolization occurs, these devices have been difficult to retrieve. Bench simulations of retrieval of PDA-R and ASD-R devices were performed in a vascular model. Retrieval of each device was attempted using snare techniques or with bioptome forceps with a range of devices. The same devices were then intentionally embolized in an animal model. Retrieval methods were systematically tested in a range of sheath sizes, and graded in terms of difficulty and retrieval time. Devices that were grasped by the bioptome in the center of the proximal part of the devices were easily retrieved in both models. Bench studies determined the minimum sheath sizes needed for retrieval of each device with this method. In general sheathes two french sizes greater than the delivery sheath were successful with this technique. Three out of the four PDA-R devices were successfully retrieved in vivo. Two were retrieved by grasping the middle of the PA end of the PDA-R device with a Maslanka bioptome and one small PDA-R device was retrieved using a 10 mm Snare. Four of the five ASD-R devices were retrieved successfully grasping the right atrial ASD-R disc or by passing a wire through the device and snaring this loop. For ASD-R 28 and 30 mm devices, a double bioptome technique was needed to retrieve the device. ASD-R and PDA-R devices can be successfully retrieved in the catheterization lab. It is critical to grab the center portion of the right atrial disc of the ASD-R device or pulmonary portion of the PDA-R device and to use adequately sized sheathes. © 2018 Wiley Periodicals, Inc.
Sinden, Kathryn; MacDermid, Joy C
2014-03-01
Employers are tasked with developing injury management and return-to-work (RTW) programs in response to occupational health and safety policies. Physical demands analyses (PDAs) are the cornerstone of injury management and RTW development. Synthesizing and contextualizing policy knowledge for use in occupational program development, including PDAs, is challenging due to multiple stakeholder involvement. Few studies have used a knowledge translation theoretical framework to facilitate policy-based interventions in occupational contexts. The primary aim of this case study was to identify how constructs of the knowledge-to-action (KTA) framework were reflected in employer stakeholder-researcher collaborations during development of a firefighter PDA. Four stakeholder meetings were conducted with employee participants who had experience using PDAs in their occupational role. Directed content analysis informed analyses of meeting minutes, stakeholder views and personal reflections recorded throughout the case. Existing knowledge sources including local data, stakeholder experiences, policies and priorities were synthesized and tailored to develop a PDA in response to the barriers and facilitators identified by the firefighters. The flexibility of the KTA framework and synthesis of multiple knowledge sources were identified strengths. The KTA Action cycle was useful in directing the overall process but insufficient for directing the specific aspects of PDA development. Integration of specific PDA guidelines into the process provided explicit direction on best practices in tailoring the PDA and knowledge synthesis. Although the themes of the KTA framework were confirmed in our analysis, order modification of the KTA components was required. Despite a complex context with divergent perspectives successful implementation of a draft PDA was achieved. The KTA framework facilitated knowledge synthesis and PDA development but specific standards and modifications to the KTA framework were needed to enhance process structure. Flexibility for modification and integration of PDA practice guidelines were identified as assets of the KTA framework during its application.
Transcatheter Patent Ductus Arteriosus Occlusion in Small Infants.
Schwartz, Matthew C; Nykanen, David; Winner, Lawrence H; Perez, Jose; McMahan, Michael; Munro, Hamish M; Suguna Narasimhulu, Sukumar
2016-12-01
Transcatheter patent ductus arteriosus (PDA) occlusion is feasible in small infants and may improve lung function in symptomatic patients. We aimed to describe transcatheter PDA closure in small infants including predictors of technical success and rate of complication and to identify factors associated with improved respiratory status after closure. All patients in the NICU at our center who were referred for transcatheter PDA occlusion between 1/2010 and 11/2014 were retrospectively identified. Relevant details were extracted. Additionally, a modification of the respiratory severity score (RSS) (FiO 2 × mean airway pressure) was used to characterize degree of pulmonary support before and at intervals after catheterization. Twenty patients were identified with median age of 96 days (13-247) and weight of 3.1 kg (1.7-4.7). The PDA was type F morphology in 14 (70%) patients. The PDA was successfully occluded in 16 (80%) patients. Ratio of minimum PDA diameter/length was >0.5 in all unsuccessful attempts and <0.4 in all successful cases (P = .01). Of the 16 cases of occlusion, Amplatzer Vascular Plug II was used in 15 (94%). No deaths or pulse loss occurred. Five (25%) patients required blood transfusion and transfusion was associated with lower hemoglobin (P = .049), lower weight (P = .008), and lower aortic pressure (P = .04). Excluding 1 patient with significant congenital heart disease, the RSS improved at 3 days in 9 (60%) patients and at 7 days in 12 (80%) compared with preintervention value. Patient factors were not associated with improved RSS at 3 or 7 days. In our cohort of symptomatic infants, transcatheter PDA occlusion was successful in most and a ratio of minimum PDA diameter/length of <0.4 was predictive of technical success. Using a surrogate for pulmonary support, the majority of patients were on less support 7 days after closure. © 2016 Wiley Periodicals, Inc.
El‐Said, Howaida G.; Bratincsak, Andras; Foerster, Susan R.; Murphy, Joshua J.; Vincent, Julie; Holzer, Ralf; Porras, Diego; Moore, John; Bergersen, Lisa
2013-01-01
Background The technique and safety of transcatheter patent ductus arteriosus (PDA) closure have evolved during the past 20 years. We sought to report a multicenter experience of PDA closure with a focus on the rate of adverse events (AE) and a review of institutional practice differences. Methods and Results Outcome data on transcatheter PDA closure were collected at 8 centers prospectively using a multicenter registry (Congenital Cardiac Catheterization Project on Outcome Registry). Between February 2007 and June 2010, 496 PDA closures were recorded using a device in 338 (68%) or coils in 158 (32%). Most patients had an isolated PDA (90%). Fifty percent of patients were between 6 months and 3 years old, with only 40 patients (8%) <6 months old. Median minimum PDA diameter was 2.5 mm (range 1 to 12 mm; IQR 2 to 3 mm) for device closure and 1 mm (range 0.5 to 6 mm; IQR 1 to 2 mm) for coil closure (P<0.001). A device rather than coil was used in patients <3 years, weight <11 kg, and with a PDA minimum diameter >2 mm (all P<0.001). Three of 8 centers exclusively used a device for PDAs with a diameter >1.5 mm. In 9% of cases (n=46), an AE occurred; however, only 11 (2%) were classified as high severity. Younger age was associated with a higher AE rate. Coil‐related AEs were more common than device‐related AEs (10% versus 2%, P<0.001). Conclusions PDA closure in the present era has a very low rate of complications, although these are higher in younger children. Technical intervention‐related events were more common in coil procedures compared with device procedures. For PDAs ≤2.5 mm in diameter, institutional differences in preference for device versus coil exist. PMID:24284214
Bhalgat, Parag S; Pinto, Robin; Dalvi, Bharat V
2012-07-01
To assess the efficacy and safety of transcatheter closure (TCC) of patent ductus arteriosus (PDA) with severe pulmonary arterial hypertension (PHT). TCC of small and moderate-sized PDAs is well established. However, there is a paucity of data on TCC of large PDA with severe PHT. This is a retrospective observational study of 76 patients with large PDA and severe PHT who were referred for TCC. Multiple clinical and investigational parameters were evaluated to decide the reversibility of PHT. Following the TCC, patients were serially followed up to assess the efficacy and safety of closure and its impact on PHT. Of 76 patients, nine were found to have PDA with Eisenmenger's syndrome. Of remaining 67, two were thought to have irreversible PHT based on hemodynamic data obtained after balloon occlusion of the duct. Sixty five patients, who eventually underwent TCC of PDA, had a median age of 9.1 years (range 1 month to 40 years). The weight ranged between 2.5 to 62 kg (median 14 kg). The PDA size was 9.1 ± 4.6 mm. The mean systolic pulmonary artery pressure was 66.9 ± 15.3 mm Hg. Duct occluder was used in 63 and muscular ventricular septal defect closure device in 2. The follow up was available in 56 (86%) with a mean follow up period of 65 ± 34 months. All the patients had complete closure of the PDA at 6 months follow up. Mild obstruction of left pulmonary artery (n=3) and aortic isthmus flow (n=6) was noted at the time of discharge. During the follow up, partial or complete resolution of PHT was observed in all the patients in whom Doppler-derived right ventricular systolic pressure was recorded (available in 40 of 56 patients). TCC of large PDA with severe PHT and significant left to right shunt was found to be effective and safe in the short and intermediate term.
Analysis of formononetin from black cohosh (Actaea racemosa).
Jiang, B; Kronenberg, F; Balick, M J; Kennelly, E J
2006-07-01
Black cohosh has been widely used as an herbal medicine for the treatment of symptoms related to menopause in America and Europe during the past several decades, but the bioactive constituents are still unknown. Formononetin is an isoflavone with known estrogen-like activity. This compound was first reported to be isolated from black cohosh in 1985, but subsequent research in 2002 using HPLC-PDA and LC-MS revealed no evidence to show the presence of formononetin in 13 populations of American black cohosh. A more recent report published in 2004 claimed to detect formononetin in an extract of black cohosh rhizomes using a TLC-fluorescent densitometry method. To further resolve these conflicting reports, we analyzed black cohosh roots and rhizomes for the presence of formononetin, using a combined TLC, HPLC-PDA and LC-MS method. We examined both methanolic and aqueous methanolic black cohosh extracts by HPLC-PDA and LC-MS methods, and did not detect formononetin in any extracts. We further determined the limits of detection of formononetin by HPLC-PDA and LC-MS. Our experimental results indicated that the sensitivity and accuracy of the HPLC-PDA and LC-MS methods for the analysis of formononetin were slightly higher than those of the reported fluorescent method, suggesting that the HPLC-PDA and LC-MS methods were reliable for the analysis of formononetin from black cohosh. We also repeated the reported TLC method to concentrate two fractions from a modern black cohosh sample and an 86-year-old black cohosh sample, respectively, and then analyzed these two fractions for formononetin using the HPLC-PDA and LC-MS method instead of the fluorescent method. Formononetin was not detected by HPLC-PDA or LC-MS. From the results of the present study it is not reasonable to attribute the estrogen-like activity of black cohosh extracts to formononetin.
USDA-ARS?s Scientific Manuscript database
We determined the phenolic, anthocyanin, and proanthocyanidin content of three brown, purple, and red rice brans isolated from different rice varieties using HPLC-PDA with the aid of 27 standards of known structure and by matching unknown peaks to a spectral library of known compounds. DPPH and ORA...
Glucose-6-phosphate dehydrogenase deficiency and sickle cell genes in Bisha.
el-Hazmi, M A; al-Swailem, A; Warsy, A S
1995-08-01
This study was conducted on 820 Saudi males and females from Bisha in the western province of Saudi Arabia. Blood samples were analysed to determine the frequency of glucose-6-phosphate dehydrogenase deficiency and haemoglobin S (Hb S) genes, and to investigate interactions between the two genes. Severe G-6-PD deficiency in this population was due to G-6-PD-Mediterranean; the African variant G-6-PD-A- was not detected. The normal and common form of the enzyme was G-6-PD-B+, occurring at a frequency of 0.8444 and 0.8177 in males and females, respectively. Variants included G-6-PD-A+, G-6-PD-Mediterranean, and G-6-PD-Mediterranean-like at frequencies of 0.0043, 0.0767, and 0.0746, respectively, in males and 0.0057, 0.05413, and 0.0855, respectively, in females. Sickle cell haemoglobin (Hb S) was encountered in the homozygous (4 per cent) and heterozygous (10 per cent) states at a gene frequency of 0.0860. No interaction between G-6-PD deficiency and Hb S gene was observed. A severe haematological and clinical presentation of the Hb SS disease was encountered in the children from Bisha.
Mitra, Souvik; Florez, Ivan D; Tamayo, Maria E; Mbuagbaw, Lawrence; Vanniyasingam, Thuva; Veroniki, Areti Angeliki; Zea, Adriana M; Zhang, Yuan; Sadeghirad, Behnam; Thabane, Lehana
2018-03-27
Despite increasing emphasis on conservative management of patent ductus arteriosus (PDA) in preterm infants, different pharmacotherapeutic interventions are used to treat those developing a hemodynamically significant PDA. To estimate the relative likelihood of hemodynamically significant PDA closure with common pharmacotherapeutic interventions and to compare adverse event rates. The databases of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception until August 15, 2015, and updated on December 31, 2017, along with conference proceedings up to December 2017. Randomized clinical trials that enrolled preterm infants with a gestational age younger than 37 weeks treated with intravenous or oral indomethacin, ibuprofen, or acetaminophen vs each other, placebo, or no treatment for a clinically or echocardiographically diagnosed hemodynamically significant PDA. Data were independently extracted in pairs by 6 reviewers and synthesized with Bayesian random-effects network meta-analyses. Primary outcome: hemodynamically significant PDA closure; secondary: included surgical closure, mortality, necrotizing enterocolitis, and intraventricular hemorrhage. In 68 randomized clinical trials of 4802 infants, 14 different variations of indomethacin, ibuprofen, or acetaminophen were used as treatment modalities. The overall PDA closure rate was 67.4% (2867 of 4256 infants). A high dose of oral ibuprofen was associated with a significantly higher odds of PDA closure vs a standard dose of intravenous ibuprofen (odds ratio [OR], 3.59; 95% credible interval [CrI], 1.64-8.17; absolute risk difference, 199 [95% CrI, 95-258] more per 1000 infants) and a standard dose of intravenous indomethacin (OR, 2.35 [95% CrI, 1.08-5.31]; absolute risk difference, 124 [95% CrI, 14-188] more per 1000 infants). Based on the ranking statistics, a high dose of oral ibuprofen ranked as the best pharmacotherapeutic option for PDA closure (mean surface under the cumulative ranking [SUCRA] curve, 0.89 [SD, 0.12]) and to prevent surgical PDA ligation (mean SUCRA, 0.98 [SD, 0.08]). There was no significant difference in the odds of mortality, necrotizing enterocolitis, or intraventricular hemorrhage with use of placebo or no treatment compared with any of the other treatment modalities. A high dose of oral ibuprofen was associated with a higher likelihood of hemodynamically significant PDA closure vs standard doses of intravenous ibuprofen or intravenous indomethacin; placebo or no treatment did not significantly change the likelihood of mortality, necrotizing enterocolitis, or intraventricular hemorrhage. PROSPERO Identifier: CRD42015015797.
Hallik, Maarja; Tasa, Tõnis; Starkopf, Joel; Metsvaht, Tuuli
2017-01-01
Milrinone has been suggested as a possible first-line therapy for preterm neonates to prevent postligation cardiac syndrome (PLCS) through decreasing systemic vascular resistance and increasing cardiac contractility. The optimal dosing regimen, however, is not known. To model the dosing of milrinone in preterm infants for prevention of PLCS after surgical closure of patent ductus arteriosus (PDA). Milrinone time-concentration profiles were simulated for 1,000 subjects using the volume of distribution and clearance estimates based on one compartmental population pharmacokinetic model by Paradisis et al. [Arch Dis Child Fetal Neonatal Ed 2007;92:F204-F209]. Dose optimization was based on retrospectively collected demographic data from neonates undergoing PDA ligation in Estonian PICUs between 2012 and 2014 and existing pharmacodynamic data. The target plasma concentration was set at 150-200 ng/ml. The simulation study used demographic data from 31 neonates who underwent PDA ligation. The median postnatal age was 13 days (range: 3-29) and weight was 760 g (range: 500-2,351). With continuous infusion of milrinone 0.33 μg/kg/min, the proportion of subjects within the desired concentration range was 0% by 3 h, 36% by 6 h, and 61% by 8 h; 99% of subjects exceeded the range by 18 h. The maximum proportion of total simulated concentrations in the target range was attained with a bolus infusion of 0.73 μg/kg/min for 3 h followed by a 0.16-μg/kg/min maintenance infusion. Mathematical simulations suggest that in preterm neonates the plasma time-concentration profile of milrinone can be optimized with a slow loading dose followed by maintenance infusion. © 2016 S. Karger AG, Basel.
Safety Evaluation of Two Commercial Lithium-ion Batteries for Space Applications
NASA Technical Reports Server (NTRS)
Jeevarajan, Judith A.; Collins, Jacob; Cook, Joseph S.
2004-01-01
Lithium-ion batteries have been used for applications on the Shuttle and Station for the past six years. A majority of the li-ion batteries flown are Commercial-off-the-shelf (COTS) varieties. The COTS batteries and cells were tested under nominal and abusive conditions for performance and safety characterization. Within the past six months two batteries have been certified for flight and use on the Space Station. The first one is a Hand Spring PDA battery that had a single prismatic li-ion cell and the second is an Iridium satellite phone that had a two-cell pack with prismatic li-ion cells.
ERIC Educational Resources Information Center
Tyler, David C.; Melvin, Joyce C.; Epp, MaryLou; Kreps, Anita M.
2014-01-01
Recently, a great deal of literature on patron-driven acquisition (PDA) has been published that addresses the implementation and results of PDA programs at academic libraries. However, despite widespread worries that PDA will lead to unbalanced collections, little attention has been paid to whether patrons' and librarians' purchasing differ…
Acceleration feedback improves balancing against reflex delay
Insperger, Tamás; Milton, John; Stépán, Gábor
2013-01-01
A model for human postural balance is considered in which the time-delayed feedback depends on position, velocity and acceleration (proportional–derivative–acceleration (PDA) feedback). It is shown that a PDA controller is equivalent to a predictive controller, in which the prediction is based on the most recent information of the state, but the control input is not involved into the prediction. A PDA controller is superior to the corresponding proportional–derivative controller in the sense that the PDA controller can stabilize systems with approximately 40 per cent larger feedback delays. The addition of a sensory dead zone to account for the finite thresholds for detection by sensory receptors results in highly intermittent, complex oscillations that are a typical feature of human postural sway. PMID:23173196
Basak, Ecem; Gumussoy, Cigdem Altin; Calisir, Fethi
2015-01-01
This study aims at identifying the factors affecting the intention to use personal digital assistant (PDA) technology among physicians in Turkey using an extended Technology Acceptance Model (TAM). A structural equation-modeling approach was used to identify the variables that significantly affect the intention to use PDA technology. The data were collected from 339 physicians in Turkey. Results indicated that 71% of the physicians' intention to use PDA technology is explained by perceived usefulness and perceived ease of use. On comparing both, the perceived ease of use has the strongest effect, whereas the effect of perceived enjoyment on behavioral intention to use is found to be insignificant. This study concludes with the recommendations for managers and possible future research.
Aggarwal, Sanjeev; Delius, Ralph E; Pettersen, Michael D
2013-01-01
We present an infant who had an anomalous left coronary artery arising from the pulmonary artery (ALCAPA) and a large patent ductus arteriosus (PDA), who was diagnosed before a potentially catastrophic closure of PDA. In the presence of normal left ventricular function and the absence of coronary artery collaterals, it is difficult to diagnose ALCAPA. A disproportionate degree of left ventricular dilation and severity of mitral valve regurgitation relative to the degree of PDA shunt, and echogenic papillary muscles on an echocardiogram should raise a suspicion of coronary artery anomalies. The infant underwent surgical ligation of PDA with translocation of coronary arteries and had an uneventful recovery. © 2012 Wiley Periodicals, Inc.
Hu, Yang; Dan, Weihua; Xiong, Shanbai; Kang, Yang; Dhinakar, Arvind; Wu, Jun; Gu, Zhipeng
2017-01-01
To improve the mechanical properties and biocompatibility of collagen I matrix, a novel and facile strategy was developed to modify porcine acellular dermal matrix (PADM) via dopamine self-polymerization followed by collagen immobilization to enhance the biological, mechanical and physicochemical properties of PADM. Mechanism study indicated that the polymerization of dopamine onto PADM surface could be regulated by controlling the amount of hydrogen bonds forming between phenol hydroxyl (COH) and nitrogen atom (NCO) within collagen fibers of PADM. The investigations of surface interactions between PDA and PADM illustrated that PDA-PADM system yielded better mechanical properties, thermal stability, surface hydrophilicity and the structural integrity of PADM was maintained after dopamine coating. Furthermore, collagen (COL) was immobilized onto the fresh PDA-PADM to fabricate the collagen-PDA-PADM (COL-PDA-PADM) complexed scaffold. The MTT assay and CLSM observation showed that COL-PDA-PADM had better biocompatibility and higher cellular attachment than pure PADM and COL-PADM without dopamine coating, thus demonstrating the efficacy of PDA as the intermediate layer. Meanwhile, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of COL-PDA-PADM were investigated by an in vivo study. The results revealed that COL-PDA-PADM could effectively promote bFGF and VEGF expression, possibly leading to enhancing the dura repairing process. Overall, this work contributed a new insight into the development of a semi-natural tissue engineering scaffold with high biocompatibility and good mechanical properties. Obtaining scaffolds with high biocompatibility and good mechanical properties is still one of the most challenging issues in tissue engineering. To have excellent in vitro and in vivo performance, scaffolds are desired to have similar mechanical and biological properties as the natural extracellular matrix, such as collagen based matrix. Utilizing the surface self-crosslinking and coating strategy, we successfully obtained a novel semi-natural platform with excellent biological and mechanical properties from porcine acellular dermal matrix (PADM), polydopamine and collagen. The results confirmed that this scaffold platform has very excellent cellular performance and very little toxicity/side effects in vivo. Therefore, this semi-natural scaffold may be an appropriate platform for tissue engineering and this strategy would further help to develop more robust scaffolds. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Liu, Yu; Tortora, George; Ryan, Maria E.; Lee, Hsi-Ming; Golub, Lorne M.
2002-01-01
The broth macrodilution method (BMM) for antifungal susceptibility testing, approved by the National Committee for Clinical Laboratory Standards (NCCLS), was found to have deficiencies in testing of the antifungal activity of a new type of antifungal agent, a nonantibacterial chemically modified tetracycline (CMT-3). The high content of phosphate in the medium was found to greatly increase the MICs of CMT-3. To avoid the interference of phosphate in the test, a new method using potato dextrose agar (PDA) as a culture medium was developed. Eight strains of fungi, including five American Type Culture Collection strains and three clinical isolates, were used to determine the MICs of amphotericin B and itraconazole with both the BMM and the PDA methods. The MICs of the two antifungal agents determined with the PDA method showed 99% agreement with those determined with the BMM method within 1 log2 dilution. Similarly, the overall reproducibility of the MICs with the PDA method was above 97%. Three other antifungal agents, fluconazole, ketoconazole, and CMT-3, were also tested in parallel against yeasts and molds with both the BMM and the PDA methods. The MICs of fluconazole and ketoconazole determined with the PDA method showed 100% agreement within 1 log2 dilution of those obtained with the BMM method. However, the MICs of CMT-3 determined with the BMM method were as high as 128 times those determined with the PDA method. The effect of phosphate on the antifungal activity of CMT-3 was evaluated by adding Na2HPO4 to PDA in the new method. It was found that the MIC of CMT-3 against a Penicillium sp. increased from 0.5 μg/ml (control) to 2.0 μg/ml when the added phosphate was used at a concentration of 0.8 mg/ml, indicating a strong interference of Na2HPO4 with the antifungal activity of CMT-3. Except for fluconazole, all the other antifungal agents demonstrated clear end points among the yeasts and molds tested. Nevertheless, with its high reproducibility, good agreement with NCCLS proposed MIC ranges, and lack of interference of phosphate, the PDA method shows promise as a useful assay for antifungal susceptibility testing and screening for new antifungal agents, especially for drugs that may be affected by high (supraphysiologic) phosphate concentrations. PMID:11959582
Ikic, Vedrana; Belanger, Claude; Bouchard, Stephane; Gosselin, Patrick; Langlois, Frederic; Labrecque, Joane; Dugas, Michel J; Marchand, Andre
2017-03-01
Panic disorder with agoraphobia (PDA) and generalized anxiety disorder (GAD) are impairing and costly disorders that are often misdiagnosed and left untreated despite multiple consultations. These disorders frequently co-occur, but little is known about the costs associated with their comorbidity and the impact of cognitive-behavioral therapy (CBT) on cost reduction. The first objective of this study was to assess the mental health-related costs associated with the specific concomitance of PDA and GAD. The second aim was to determine whether there is a reduction in direct and indirect mental health-related costs following conventional CBT for the primary disorder only (PDA or GAD) or combined CBT adapted to the comorbidity (PDA and GAD). A total of 123 participants with a double diagnosis of PDA and GAD participated in this study. Direct and indirect mental health-related costs were assessed and calculated from a societal perspective at the pre-test, the post-test, and the three-month, six-month and one-year follow-ups. At the pre-test, PDA-GAD comorbidity was found to generate a mean total cost of CADUSD 2,000.48 (SD = USD 2,069.62) per participant over a three-month period. The indirect costs were much higher than the direct costs. Both treatment modalities led to significant and similar decreases in all cost categories from the pre-test to the post-test. This reduction was maintained until the one-year follow-up. Methodological choices may have underestimated cost evaluations. Nonetheless, this study supports the cost offset effects of both conventional CBT for primary PDA or GAD and combined CBT for PDA-GAD comorbidity. Treatment of comorbid and costly disorders with evidence-based treatments such as CBT may lead to considerable economic benefits for society. Considering the limited resources of healthcare systems, it is important to make choices that will lead to better accessibility of quality services. The application of CBT for PDA, GAD or both disorders and training mental health professionals in this therapeutic approach should be encouraged. Additionally, it would be favorable for insurance plans to reimburse employees for expenses associated with psychological treatment for anxiety disorders. In addition to symptom reduction, it would be of great pertinence to explore which factors can contribute to reducing direct and indirect mental health-related costs.
Clauson, Kevin A; Polen, Hyla H; Peak, Amy S; Marsh, Wallace A; DiScala, Sandra L
2008-11-01
Clinical decision support tools (CDSTs) on personal digital assistants (PDAs) and online databases assist healthcare practitioners who make decisions about dietary supplements. To assess and compare the content of PDA dietary supplement databases and their online counterparts used as CDSTs. A total of 102 question-and-answer pairs were developed within 10 weighted categories of the most clinically relevant aspects of dietary supplement therapy. PDA versions of AltMedDex, Lexi-Natural, Natural Medicines Comprehensive Database, and Natural Standard and their online counterparts were assessed by scope (percent of correct answers present), completeness (3-point scale), ease of use, and a composite score integrating all 3 criteria. Descriptive statistics and inferential statistics, including a chi(2) test, Scheffé's multiple comparison test, McNemar's test, and the Wilcoxon signed rank test were used to analyze data. The scope scores for PDA databases were: Natural Medicines Comprehensive Database 84.3%, Natural Standard 58.8%, Lexi-Natural 50.0%, and AltMedDex 36.3%, with Natural Medicines Comprehensive Database statistically superior (p < 0.01). Completeness scores were: Natural Medicines Comprehensive Database 78.4%, Natural Standard 51.0%, Lexi-Natural 43.5%, and AltMedDex 29.7%. Lexi-Natural was superior in ease of use (p < 0.01). Composite scores for PDA databases were: Natural Medicines Comprehensive Database 79.3, Natural Standard 53.0, Lexi-Natural 48.0, and AltMedDex 32.5, with Natural Medicines Comprehensive Database superior (p < 0.01). There was no difference between the scope for PDA and online database pairs with Lexi-Natural (50.0% and 53.9%, respectively) or Natural Medicines Comprehensive Database (84.3% and 84.3%, respectively) (p > 0.05), whereas differences existed for AltMedDex (36.3% vs 74.5%, respectively) and Natural Standard (58.8% vs 80.4%, respectively) (p < 0.01). For composite scores, AltMedDex and Natural Standard online were better than their PDA counterparts (p < 0.01). Natural Medicines Comprehensive Database achieved significantly higher scope, completeness, and composite scores compared with other dietary supplement PDA CDSTs in this study. There was no difference between the PDA and online databases for Lexi-Natural and Natural Medicines Comprehensive Database, whereas online versions of AltMedDex and Natural Standard were significantly better than their PDA counterparts.
Tilahun, Birkneh; Tefera, Endale
2013-05-31
Patent ductus arteriosus (PDA) is one of the commonest congenital heart diseases that require closure within the first few months after birth. The residential area of patients affects the size of the PDA: living in highlands, like most places in Ethiopia, is a risk for having larger sized PDA. Closure of these congenital heart defects is usually performed at an early age in places where capable centers are available. In Ethiopia, closure of these defects is done on mission basis often at an older age. Recently, limited reports came about the occurrence of postoperative left ventricular systolic dysfunction (POLVD) following closure of PDA though full explanation is still lacking. To determine the rate of and time to improvement of POLVD and the factors associated with it in children and adolescents who underwent surgical closure of PDA. All children and adolescents who underwent surgical closure of PDA at the Cardiac Center, Ethiopia (CCE) had postoperative follow up with echocardiography. Serial left ventricular ejection fraction (LVEF) and fiber shortening (FS) values were recorded for all of them. SPSS 20 was used to analyze the data. A total of 36 children and adolescents who underwent surgical closure of PDA from January 2009 to December 2012 and who fulfilled the inclusion criteria were studied. Their mean age at intervention was 8.52 years (SD = 5.23 years), 77.80% were females. The mean duct size as determined by either echocardiography or intra-operative by the surgeon was 10.31 mm (SD = 3.20 mm). They were followed for a mean duration of 24.80 months (SD = 12.36 months) following surgical closure of PDA. The mean LVEF and FS decreased from 65.06% and 35.28% preoperatively to 54.83% and 28.40% post-operatively respectively. Fifteen (42.86%) of the patients had a post-operative LVEF of less than 55%. The mean time to normalization of systolic function was 5.11 weeks (SD = 3.30 weeks). Having an associated cardiac lesion was an independent predictor of POLVD. We conclude that there is a high rate of POLVD following surgical closure of large PDA in highlanders. We recommend a serial and systematic follow up of these children postoperatively. Those with a significant cardiac dysfunction may need cardiac medications like Angiotensin Converting Enzyme Inhibitors (ACEI).
Cai, Aijun; Wang, Xiuping; Guo, Aiying; Chang, Yongfang
2016-09-01
Polydopamine-Ag-AgCl composites (PDA-Ag-AgCl) were synthesized using a mussel-inspired method at room temperature, where PDA acts as a reducing agent to obtain the noble Ag nanoparticles from a precursor. The morphologies and structures of the as-prepared PDA-Ag-AgCl were characterized by several techniques including field emission scanning electron microscopy (FESEM), transmission electron microscopy (SEM), Raman spectra, and X-Ray photoelectron spectrum (XPS). The morphological observation depicts formation of nanoparticles with various micrometer size diameters and surface XPS analysis shows presence of various elements including Ag, N, Cl, and O. The enhanced absorbance of the PDA-Ag-AgCl particles in the visible light region is confirmed through UV-Vis diffuse reflectance spectra (DRS), and the charge transfer is demonstrated by photoluminescence (PL) and photocurrent response. The synthesized PDA-Ag-AgCl composites could be used as visible-light-driven photocatalysts for the degradation of Rhodamine B. The elevated photocatalytic activity is ascribed to the effective charge transfer from plasmon-excited Ag to AgCl that can improve the efficiency of the charge separation during the photocatalytic reaction. Furthermore, differences in the photocatalytic performance among the different PDA-Ag-AgCl composites are noticed that could be attributed to the Brunauer-Emmett-Teller (BET) specific surface area, which benefits to capture the visible light efficiently. The PDA-Ag-AgCl exhibits excellent stability without a significant loss in activity after 5cycles. The proposed method is low-cost and environmentally friendly, hence a promising new way to fabricate plasmon photocatalysts. Copyright © 2016. Published by Elsevier B.V.
Engel, K R; Obst, K; Bandelow, B; Dechent, P; Gruber, O; Zerr, I; Ulrich, K; Wedekind, D
2016-09-01
There is evidence that besides limbic brain structures, prefrontal and insular cortical activations and deactivations are involved in the pathophysiology of panic disorder. This study investigated activation response patterns to stimulation with individually selected panic-specific pictures in patients with panic disorder with agoraphobia (PDA) and healthy control subjects using functional magnetic resonance imaging (fMRI). Structures of interest were the prefrontal, cingulate, and insular cortex, and the amygdalo-hippocampal complex. Nineteen PDA subjects (10 females, 9 males) and 21 healthy matched controls were investigated using a Siemens 3-Tesla scanner. First, PDA subjects gave Self-Assessment Manikin (SAM) ratings on 120 pictures showing characteristic panic/agoraphobia situations, of which 20 pictures with the individually highest SAM ratings were selected. Twenty matched pictures showing aversive but not panic-specific stimuli and 80 neutral pictures from the International Affective Picture System were chosen for each subject as controls. Each picture was shown twice in each of four subsequent blocks. Anxiety and depression ratings were recorded before and after the experiment. Group comparisons revealed a significantly greater activation in PDA patients than control subjects in the insular cortices, left inferior frontal gyrus, dorsomedial prefrontal cortex, the left hippocampal formation, and left caudatum, when PA and N responses were compared. Comparisons for stimulation with unspecific aversive pictures showed activation of similar brain regions in both groups. Results indicate region-specific activations to panic-specific picture stimulation in PDA patients. They also imply dysfunctionality in the processing of interoceptive cues in PDA and the regulation of negative emotionality. Therefore, differences in the functional networks between PDA patients and control subjects should be further investigated.
[Factors influencing the prognosis of patent ductus arteriosus in very low birth weight infants].
Wang, Chen-Hong; Shi, Li-Ping; Ma, Xiao-Lu; Luo, Fang; Chen, Zheng; Lin, Hui-Jia; DU, Li-Zhong
2016-08-01
To investigate the factors influencing the prognosis of patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants. A total of 194 VLBW infants who were admitted from January 2012 to December 2014 were enrolled as study subjects. According to cardiac ultrasound findings and treatment outcome, these infants were divided into non-PDA group, spontaneous closure group, pharmaceutical closure group, and surgical closure group. Their clinical and echocardiographic characteristics were analyzed. The spontaneous closure rate of PDA was 58.7%. The spontaneous closure group showed significantly higher gestational age, birth weight, and proportion of small-for-gestational-age infants than the pharmaceutical and surgical closure groups (P<0.05). The pharmaceutical and surgical closure groups had a significantly higher incidence rate of neonatal respiratory distress syndrome and a significantly higher proportion of infants who were given pulmonary surfactant (PS) than the spontaneous closure group (P<0.05). During different periods of time, the spontaneous closure group had a significantly smaller ductus arteriosus diameter than the pharmaceutical and surgical closure groups (P<0.05). The multivariate logistic regression analysis showed that gestational age, application of PS, and ductus arteriosus diameter at 48 hours were significantly associated with the prognosis of PDA. The major transductal flow pattern in the spontaneous closure group was closing pattern, while in the pharmaceutical and surgical closure groups, the main flow patterns were pulmonary hypertension and growing patterns within 48 hours and growing pattern on days 4 and 7. The VLBW infants have a high spontaneous closure rate of PDA. A decreased closure rate of PDA is associated with the lower gestational age and the application of PS. PDA with a large ductus arteriosus diameter and a growing or pulsatile flow pattern cannot easily achieve spontaneous closure.
Boutet, B G; Saunders, A B; Gordon, S G
2017-05-01
The median age at presentation for dogs with patent ductus arteriosus (PDA) is <6 months of age, and closure is associated with a decrease in heart size and increased survival time, which are not well described in older dogs. To describe the clinical characteristics of dogs with PDA ≥5 years of age at the time of presentation to a veterinary referral hospital. 35 client-owned dogs. Retrospective case series. PDA was diagnosed at a median age of 7.4 years (range, 5.1-12.3 years). Females represented 23/35 (65.7%) of the patients. Concurrent heart disease included degenerative mitral valve disease (DMVD; 13), arrhythmias (11), pulmonary hypertension (7), and other congenital defects (2). Cardiomegaly was documented in the majority of dogs consisting of left ventricular enlargement (91%) and left atrial enlargement (86%). Median vertebral heart size in 24 dogs was 12.9 (range, 10.7-18.2). The PDA shunt direction was left-to-right in 33 and bidirectional in 2 dogs. Closure was performed in 26 dogs, including 4 with pulmonary hypertension. In 10 dogs receiving furosemide pre-operatively for management of heart failure, furosemide was discontinued (8) or the dosage decreased (2) at the time of discharge. Adult dogs can present with a left-to-right shunting PDA that results in cardiomegaly and clinical signs that can improve or resolve with PDA closure. This improvement is also apparent in dogs with PDA complicated by DMVD. Pulmonary hypertension that does not result in complete right-to-left shunting should not be considered a contraindication to closure. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
O'Byrne, Michael L; Kennedy, Kevin F; Rome, Jonathan J; Glatz, Andrew C
2018-02-01
Practice variation is a potentially important measure of healthcare quality. The IMPACT registry provides a representative national sample with which to study practice variation in trans-catheter interventions for congenital heart disease. We studied cases for closure of atrial septal defect (ASD) and patent ductus arteriosus (PDA) in IMPACT between January 1, 2011, and September 30, 2015, using hierarchical multivariate models studying (1) the distribution of indications for closure and (2) in patients whose indication for closure was left (LVVO) or right ventricular volume overload (RVVO), the factors influencing probability of closure of a small defect (either in size or in terms of the magnitude of shunt). Over the study period, 5233 PDA and 4459 ASD cases were performed at 77 hospitals. The indications for ASD closure were RVVO in 84% and stroke prevention in 13%. Indications for PDA closure were LVVO in 57%, endocarditis prevention in 36%, and pulmonary hypertension in 7%. There was statistically significant variability in indications between hospitals for PDA and ASD procedures (median rate ratio (MRR): 1.3 and 1.1; both P<.001). The proportion of cases for volume overload with a Qp:Qs <1.5:1 decreased with increasing PDA and ASD procedural volume (P=.04 and 0.05). For ASD, the proportion was higher at hospitals with a larger proportion of adult cases (P=.0007). There was significant variation in practice in the risk of closing PDA <2 mm for LVVO (MRR: 1.4, P<.001). There is measurable variation in transcatheter closure of PDA and ASD. Further research is necessary to study whether this affects outcomes or resource utilization. Copyright © 2017 Elsevier Inc. All rights reserved.
Patent ductus arteriosus in cats (Felis catus): 50 cases (2000-2015).
Bascuñán, A; Thieman Mankin, K M; Saunders, A B; Bright, J M; Scharf, V; Singh, A; O'Sullivan, L; Brisson, B; Estrada, A H; Tou, S P; Ruoff, C
2017-02-01
To describe signalment, clinical characteristics, diagnostic, treatment, and outcome data in a large case series of cats with patent ductus arteriosus (PDA). Fifty cats with confirmed PDA. Retrospective review of medical records from five referral veterinary hospitals for cats with PDA between 2000 and 2015. Cats were included if a PDA was visualized echocardiographically, during surgery, or on post-mortem examination. Median age at presentation was 6 months (range: 36 days-9.7 years; n = 50), and sex distribution was approximately equal (27 male, 23 female). Most cats did not have clinical signs (70.2%; 33/47) at the time of presentation. Murmurs were classified as continuous (55%; 22/40) or systolic (45%; 18/40). Echocardiography confirmed left-to-right shunting in 33 cats (82.5%; 33/40) and right-to-left shunting in 7 (17.5%; 7/40). Concurrent cardiac anomalies were identified in 54.5% (18/33) and pulmonary hypertension in 45.7% (16/35). Closure was pursued in 68% (34/50), and complications associated with the procedure occurred in 14.7% (5/34) of cats, including one intraoperative mortality. Long-term follow up was available in 80% (40/50) of cats. Cats with PDA often do not display clinical signs and may not have the characteristic physical examination findings typical of PDA in dogs. An increased prevalence of concurrent cardiac anomalies and pulmonary hypertension were found relative to previous reports. Thoracic radiographs and echocardiogram may provide the most comprehensive information for making a diagnosis and treatment recommendations. PDA closure was associated with a favorable long-term outcome in cats included in this study. Copyright © 2016 Elsevier B.V. All rights reserved.
Cordero, L; Nankervis, C A; Delooze, D; Giannone, P J
2007-03-01
Indomethacin prophylaxis or expectant treatment are common strategies for the prevention or management of symptomatic patent ductus arteriosus (sPDA). To compare the clinical responses of extremely low birth weight (ELBW) infants to indomethacin prophylaxis with that of other infants who were managed expectantly by being treated with indomethacin or surgically only after an sPDA was detected. Retrospective cohort investigation of 167 ELBW infants who received indomethacin prophylaxis (study) and 167 ELBW infants (control) treated expectantly who were matched by year of birth (1999 to 2006), birth weight, gestational age (GA) and gender. Mothers of the two groups of infants were comparable demographically and on the history of preterm labor, pre-eclampsia, antepartum steroids and cesarean delivery. Study and control infants were similar in birth weight, GA, low 5 min Apgar scores, surfactant administration, the need for arterial blood pressure control, bronchopulmonary dysplasia and neonatal mortality. Necrotizing enterocolitis, spontaneous intestinal perforations, intraventricular hemorrhage grade III to IV, periventricular leukomalacia and stage 3 to 5 retinopathy of prematurity occurred also with similar frequency in both groups of infants. In the indomethacin prophylaxis group, 29% of the infants developed sPDA, and of them 38% responded to indomethacin treatment. In the expectantly treated group, 37% developed sPDA, and of them 59% responded to indomethacin treatment. Overall, surgical ligation rate for sPDA was similar between both groups of patients. In our experience, indomethacin prophylaxis does not show any advantages over expectant early treatment on the management of sPDA in ELBW infants. Although no deleterious effects were observed, prophylaxis exposed a significant number of infants who may have never developed sPDA, to potential indomethacin-related complications.
Akar, Selahattin; Karadag, Nilgun; Gokmen Yildirim, Tulin; Toptan, Handan Hakyemez; Dincer, Emre; Tuten, Abdulhamit; Yavuz, Taner; Topcuoglu, Sevilay; Karatepe, Hande Ozgun; Ozalkaya, Elif; Karatekin, Guner; Ovali, Fahri
2016-12-01
The aim of this study is to evaluate whether the platelet mass in the first 24 h of life is effective on closure of patent ductus arteriosus (PDA) or not. Preterm infants with a gestational age of < 32 weeks, hospitalized at a tertiary neonatal intensive care unit (NICU) and requiring medical treatment (intravenous or oral ibuprofen) for hemodinamically significant PDA (hsPDA) were enrolled in this study. The patients were divided into two groups after first course of pharmacologic treatment according to closure of PDA (Group 1: PDA closure, Group 2: PDA without closure). Groups were compared in terms of demographics findings, morbidities, platelet measurements like counts, mean platelet volume (MPV) and platelet mass (platelet count × mean platelet volume). The study included 77 preterm newborns in Group 1, and 30 preterms in Group 2. There were no differences in birth weight, gestational age, gender and maternal risk factors between the study groups. The mean platelet count in the first postnatal blood count was in Group 1: 211.3 ± 89.2 × 10(3)/mm(3) and in Group 2: 216.5 ± 26 × 10(3)/mm(3), respectively (p = 0.783). The mean platelet volumes (MPV) were similar in both groups (p = 0.535). No statistically significant difference between platelet mass values was detected (Group 1: 1811 ± 884 fl/nl, Group 2: 1868 ± 717 fl/nl) (p = 0.753). Our data suggest that platelet count, MPV and platelet mass did not affect the closure of hsPDA with ibuprofen.
2006-11-01
WPSM system worn by future Warfighters, the medic will have a personal digital assistant (PDA) equipped with the Battlefield Medical Information...has been hit by a bullet or some other projectile. This information is sent wirelessly to a personal digital assistant (PDA) held by the medic...likely to view this vital sign information on a personal digital assistant (PDA) equipped with the Battlefield Medical Information System – Tactical
Ertl, Lorenz; Christ, Frank
2007-08-01
Better quality bystander first-aid could improve outcome rates for emergency victims significantly. In this case-control study, we hypothesised that expert knowledge presented step-by-step to untrained helpers using a personal digital assistant (PDA), would improve the quality of bystanders basic life support. We confronted 101 lay-helpers with two standard emergency situations. (1) An unconscious trauma victim with severe bleeding. (2) Cardiopulmonary resuscitation (CPR). Performance was assessed using an Objective Structured Clinical Examination (OSCE). One group was supported by a PDA providing visual and audio instructions, whereas the control group acted only with their current knowledge. The expert system was programmed in HTML-code and displayed on the PDA's Internet browser. The maximum score obtainable was 24 points corresponding to optimal treatment. The control group without the PDA reached 14.8+/-3.5 (mean value+/-standard deviation), whereas the PDA supported group scored significantly higher (21.9+/-2.7, p<0.01). The difference in performance was measurable in all criteria tested and particularly notable in the items: placing in recovery position, airway management and quality of CPR. The PDA based expert system increased the performance of untrained helpers supplying emergency care significantly. Since Internet compatible mobile devices have become widely available, a significant quality improvement in bystander first-aid seems possible.
Wong, Charles; Mak, Michael; Shivananda, Sandesh; Yang, Junmin; Shah, Prakeshkumar S; Seidlitz, Wendy; Pemberton, Julia; Fitzgerald, Peter G; Cameron, Brian H
2013-05-01
Preterm infants needing patent ductus arteriosus (PDA) ligation are transferred to a pediatric cardiac center (CC) unless the operation can be done locally by a pediatric surgeon at a non-cardiac center (NCC). We compared infant outcomes after PDA ligation at CC and NCC. We analyzed 990 preterm infants who had PDA ligation between 2005 and 2009 using the Canadian Neonatal Network database. In-hospital mortality and major morbidities were compared between CC (n=18) and NCC (n=9). SNAP-II-adjusted mortality rates were similar (CC=8.7% vs NCC=10.7%, P=.32). Significant cranial ultrasound abnormalities (CC=24.1% vs NCC=32.1%, P<.01) and culture-proven sepsis (CC=39.7% vs NCC=54.8%, P<.01) were more frequent in infants treated at NCC. Infants transferred to CC had higher rates of cranial ultrasound abnormalities (transferred 31.6% vs non-transferred 20.4%, P<.01). NSAIDs prior to PDA ligation were used more often at NCC (CC 36.6% vs NCC 75.6%, P<.001). Mortality rates after PDA ligation were similar at CC and NCC, but cranial ultrasound abnormalities and sepsis rates were higher at NCC. Higher morbidity may be associated with different PDA management strategies, including NSAID use or infant transfer. Further studies are needed to investigate the reasons for these differences in morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Yubin; Feng, Ziliang; He, Yi; Fan, Yi; Ma, Jing; Yin, Xiangying
2018-05-01
With dopamine and NiFe2O4 particles, a novel modified cotton fabric (PDA-NiFe2O4@CF) was prepared by one-pot method. Surface morphology, composition of the PDA-NiFe2O4@CF were investigated with SEM, EDX, XRD and FT-IR, respectively. According to the results, the cotton fiber surface was well coated with NiFe2O4 particles. Subsequently, wetting behavior of the modified cotton fabric was determined. The PDA-NiFe2O4@CF is superamphiphilic in air, and a dual lyophobic behavior was indicated with an oil contact angle (OCA) of 153° under water and a water contact angle (WCA) of 145° under oil. The rough micro-nano scale surface structure and high-surface-energy compositions of the PDA-NiFe2O4@CF makes the surface to be easily covered by one medium and enables it to repel other unmixable medium simultaneously. Therefore, water-oil mixtures can be separated on demand. Besides, with the unusual dual lyophobic surface of PDA-NiFe2O4@CF, both two types of emulsions were separated by gravity driven. On the other hand, it was also found that the as-prepared PDA-NiFe2O4@CF had good adsorption performance for methylene blue.
Nay, William; Brown, Ruth; Roberson-Nay, Roxann
2013-06-30
Few naturalistic, longitudinal studies of panic disorder with and without agoraphobia (PD/PDA) exist, limiting our knowledge of the temporal rates of incidence, relapse, and chronicity, or the factors that predict category transition. Data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) wave 1 (n=43,093) and wave 2 (n=34,653) were utilized to determine transitional rates, and predictors of category transitions, over a 3-year period. Analyses revealed very high 3-year remission rates for PD and PDA (75% and 67%, respectively), although relapse also was relatively frequent (PD=12%; PDA=21%). Logistic regression revealed previous history of panic attacks, generalized anxiety disorder/major depression (GAD/MDD), nicotine dependence, female sex, younger age, and major financial crises to be reliable predictors of incidence and relapse. The direction and magnitude of association of many predictor variables were similar for PD and PDA, with notable exceptions for social anxiety and romantic relationship factors. Clinicians should be aware of the relapsing-remitting nature of PD and PDA and, thus, take caution to not reduce or eliminate effective treatments prematurely. Similarly, the current study suggests clinicians pay particular attention to concurrent factors relevant to relapse in PD/PDA that may also be clinically addressed (e.g., co-morbid MDD/GAD and nicotine dependence). Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Petrowski, Katja; Wintermann, Gloria; Smolka, Michael N; Huebner, Thomas; Donix, Markus
2014-01-01
Panic disorder with agoraphobia (PD-A) has been associated with abnormal neural activity for threat-related stimuli (faces, places). Recent findings suggest a disturbed neural processing of emotionally neutral stimuli at a more general level. Using functional magnetic resonance imaging (fMRI) we investigated the neural processing of emotionally neutral faces and places in PD-A. Fifteen patients with PD-A and fifteen healthy subjects participated in the study. When they perceived neutral faces and places, the patients with PD-A showed significantly less brain activity in the fusiform gyrus, the inferior occipital gyrus, the calcarine gyrus, the cerebellum, and the cuneus compared with the healthy controls. However, the patients with PD-A showed significantly more brain activity in the precuneus compared with controls subjects. It was not possible to distinguish the agoraphobia-associated effects from possible contributions due to general anxiety induced by fMRI. For future investigations, an additional clinical control group with patients suffering from panic disorder without agoraphobia would be of interest. In addition, the psychopathology concerning the agoraphobic symptoms needs to be investigated in more detail. The findings suggest altered neural processing of emotionally neutral faces and places in patients with PD-A. Reduced neural activity in different brain regions may indicate difficulties in recognizing the emotional content in face and place stimuli due to anxiety-related hyper-arousal. © 2013 Published by Elsevier B.V.
Yokota, Tomohiro; Aida, Takashi; Ichikawa, Yasuhiro; Fujita, Takayuki; Yokoyama, Utako; Minamisawa, Susumu
2012-08-01
Patent ductus arteriosus (PDA) is a common life-threatening complication among premature infants. Although cyclooxygenase inhibitors are frequently used to treat PDA, as they inhibit the synthesis of prostaglandin E(2), the most potent vasodilator in the ductus arteriosus (DA), their efficacy is often limited. As thromboxane A(2) (TXA(2)) induces vascular contraction via the TXA(2) receptor (TP), we hypothesized that TP stimulation would promote DA closure. To measure the inner diameter of the vessels, a rapid whole-body freezing method was used. Injection of the selective TP agonists U46619 and I-BOP constricted the fetal DA at embryonic day 19 (e19) and e21 in a dose-dependent manner. Of note, U46619 also exerted a vasoconstrictive effect on two different types of postnatal PDA models: premature PDA and hypoxia-induced PDA. We also found that U46619 constricted the ex vivo DA ring to a greater extent than it constricted the ex vivo aorta. Furthermore, we found that U46619 at lower concentrations (up to 0.05 mg/g of body weight) had a minimal vasoconstrictive effect on other vessels and did not induce microthrombosis in the pulmonary capillary arteries. Low-dose TP stimulation constricts the DA with minimal adverse effects at least in rat neonates and our results could point to an alternative potent vasoconstrictor for PDA.
Acquired heart block: a possible complication of patent ductus arteriosus in a preterm infant.
Grasser, Monika; Döhlemann, Christoph; Mittal, Rashmi; Till, Holger; Dietz, Hans-Georg; Münch, Georg; Holzinger, Andreas
2008-01-01
A large patent ductus arteriosus (PDA) is a frequently encountered clinical problem in extremely low birth weight (ELBW) infants. It leads to an increased pulmonary blood flow and in a decreased or reversed diastolic flow in the systemic circulation, resulting in complications. Here we report a possible complication of PDA not previously published. On day 8 of life, a male ELBW infant (birth weight 650 g) born at a gestational age of 23 weeks and 3 days developed an atrioventricular block (AV block). The heart rate dropped from 168/min to 90/min, and the ECG showed a Wenckebach second-degree AV block and intraventricular conduction disturbances. Echocardiography demonstrated a PDA with a large left-to-right shunt and large left atrium and left ventricle with high contractility. Within several minutes after surgical closure of the PDA, the heart rate increased, and after 30 min the AV block had improved to a 1:1 conduction ratio. Echocardiography after 2 h revealed a significant decrease of the left ventricular and atrial dimensions. Within 12 h, the AV block completely reversed together with the intraventricular conduction disturbances. We suggest that PDA with a large left-to-right shunt and left ventricular volume overload may lead to an AV block in an ELBW infant. Surgical closure of the PDA may be indicated. (c) 2007 S. Karger AG, Basel.
Li, Li; Lurie, Ira S
2015-09-01
DESIGNER: phenethylamines (PEAs) and cathinones have been encountered worldwide. Complete characterization of these substances can be challenging due to their chirality and variably substituted phenyl rings. In this study, 24 PEAs and cathinones were analyzed by ultra high performance liquid chromatography with photo diode array detection (UHPLC-PDA) on a variety of stationary phases, and by capillary electrophoresis on a dynamically coated capillary with PDA detection (CE-PDA). In the UHPLC-PDA study, a BEH Phenyl column resolved 18 of the 24 regioisomers in 8min, with good discrimination of the PEAs. In contrast, capillary zone electrophoresis (CZE) on a dynamically coated capillary partially or baseline resolved only 10 of the 24 regioisomers, but with improved discrimination of mono-substituted cathinones. A second series of CE-PDA experiments using 80mM (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) in the run buffer resolved all 24 regioisomers and all but two sets of enantiomers within 18min. Five illicit samples were successfully analyzed using the described methods. Published by Elsevier Ireland Ltd.
Jing, Yanqiu; Yuan, Xiuxiu; Yuan, Qiu; He, Kuanxin; Liu, Yingjie; Lu, Ping; Li, Huaiqi; Li, Bin; Zhan, Hui; Li, Guangliang
2016-01-01
Polydopamine functionalized reduced graphene oxide-gold nanoparticle (PDA-RGO/Au) nanocomposites were successfully prepared by a simple and mild procedure. The PDA-RGO/Au nanocomposite is successfully formed in an aqueous buffer solution (pH 8.5) without using any reducing agent. FTIR confirmed the successful coating of PDA and informed the reduction of the surface functional groups of GO. The formation of reduced GO and Au NPs was further evidenced by UV-Vis and X-ray diffraction spectroscopy. This method is environmentally friendly and highly beneficial for the mass production of graphene-noble metal based nanocomposite. The as prepared PDA-RGO/Au nanocomposite could greatly enhance the electrochemical oxidation of nicotine. We fabricated an electrochemical nicotine sensor based on the prepared PDA-RGO/Au nanocomposite. The proposed nicotine sensor showed a wide detection range from 0.05 to 500 μM with a low detection limit of 0.015 μM. Moreover, the proposed nicotine sensor was also successfully applied for determination nicotine content in tobacco products. PMID:27374974
NASA Astrophysics Data System (ADS)
Jing, Yanqiu; Yuan, Xiuxiu; Yuan, Qiu; He, Kuanxin; Liu, Yingjie; Lu, Ping; Li, Huaiqi; Li, Bin; Zhan, Hui; Li, Guangliang
2016-07-01
Polydopamine functionalized reduced graphene oxide-gold nanoparticle (PDA-RGO/Au) nanocomposites were successfully prepared by a simple and mild procedure. The PDA-RGO/Au nanocomposite is successfully formed in an aqueous buffer solution (pH 8.5) without using any reducing agent. FTIR confirmed the successful coating of PDA and informed the reduction of the surface functional groups of GO. The formation of reduced GO and Au NPs was further evidenced by UV-Vis and X-ray diffraction spectroscopy. This method is environmentally friendly and highly beneficial for the mass production of graphene-noble metal based nanocomposite. The as prepared PDA-RGO/Au nanocomposite could greatly enhance the electrochemical oxidation of nicotine. We fabricated an electrochemical nicotine sensor based on the prepared PDA-RGO/Au nanocomposite. The proposed nicotine sensor showed a wide detection range from 0.05 to 500 μM with a low detection limit of 0.015 μM. Moreover, the proposed nicotine sensor was also successfully applied for determination nicotine content in tobacco products.
Zhang, Chao; Li, Hao-Nan; Du, Yong; Ma, Meng-Qi; Xu, Zhi-Kang
2017-02-07
Mussel-inspired polydopamine (PDA) coatings have been broadly exploited for constructing functional membrane surfaces. One-step codeposition of PDA with antifouling polymers, especially zwitterionic polymers, has been regarded as a promising strategy for fabricating antifouling membrane surfaces. However, one challenge is that the codeposition is usually a slow process over 10 h or even several days. Herein, we report that CuSO 4 /H 2 O 2 is able to notably accelerate the codeposition process of PDA with poly(sulfobetaine methacrylate) (PSBMA). In our case, PSBMA is facilely anchored to the polypropylene microporous membrane (PPMM) surfaces within 1 h with the assistance of PDA because of its strong interfacial adhesion. The PDA/PSBMA-coated PPMMs show excellent surface hydrophilicity, high water permeation flux (7506 ± 528 L/m 2 ·h at 0.1 MPa), and an outstanding antifouling property. Moreover, the antifouling property is maintained after the membranes are treated with acid and alkali solutions as well as organic solvents. To recap, it provides a facile, universal, and time-saving strategy for exploiting high-efficiency and durable antifouling membrane surfaces.
A wireless PDA-based physiological monitoring system for patient transport.
Lin, Yuan-Hsiang; Jan, I-Chien; Ko, Patrick Chow-In; Chen, Yen-Yu; Wong, Jau-Min; Jan, Gwo-Jen
2004-12-01
This paper proposes a mobile patient monitoring system, which integrates current personal digital assistant (PDA) technology and wireless local area network (WLAN) technology. At the patient's location, a wireless PDA-based monitor is used to acquire continuously the patient's vital signs, including heart rate, three-lead electrocardiography, and SpO2. Through the WLAN, the patient's biosignals can be transmitted in real-time to a remote central management unit, and authorized medical staffs can access the data and the case history of the patient, either by the central management unit or the wireless devices. A prototype of this system has been developed and implemented. The system has been evaluated by technical verification, clinical test, and user survey. The evaluation of performance yields a high degree of satisfaction (mean = 4.64, standard deviation--SD = 0.53 in a five-point Likert scale) of users who used the PDA-based system for intrahospital transport. The results also show that the wireless PDA model is superior to the currently used monitors both in mobility and in usability, and is, therefore, better suited to patient transport.
Roy, Lopamudra Das; Sahraei, Mahnaz; Subramani, Durai B.; Besmer, Dahlia; Nath, Sritama; Tinder, Teresa L.; Bajaj, Ekta; Shanmugam, Kandavel; Lee, Yong Yook; Hwang, Sun IL; Gendler, Sandra J.; Mukherjee, Pinku
2010-01-01
Increased motility and invasiveness of pancreatic cancer cells are associated with epithelial to mesenchymal transition (EMT). Snai1 and Slug are zinc-finger transcription factors that trigger this process by repressing E-cadherin and enhancing vimentin and N-Cadherin protein expression. However, the mechanisms that regulate this activation in pancreatic tumors remain elusive. MUC1, a transmembrane mucin glycoprotein, is associated with the most invasive forms of pancreatic adenocarcinomas (PDA). In this study, we show that over expression of MUC1 in pancreatic cancer cells triggers the molecular process of EMT which translates to increased invasiveness and metastasis. EMT was significantly reduced when Muc1 was genetically deleted in a mouse model of PDA or when all seven tyrosines in the cytoplasmic tail of MUC1 were mutated to phenylalanine (mutated MUC1 CT). Using proteomics, RT-PCR, and Western blotting, we revealed a significant increase in vimentin, Slug and Snail expression with repression of E-Cadherin in MUC1-expressing cells compared to cells expressing the mutated MUC1 CT. In the cells that carried the mutated MUC1 CT, MUC1 failed to co-immunoprecipitate with β-catenin and translocate to the nucleus thereby blocking transcription of the genes associated with EMT and metastasis. Thus, functional tyrosines are critical in stimulating the interactions between MUC1 and β-catenin and their nuclear translocation to initiate the process of EMT. This study signifies the oncogenic role of MUC1 CT and is the first to identify a direct role of the MUC1 in initiating EMT during pancreatic cancer. The data may have implications in future design of MUC1-targeted therapies for pancreatic cancer. PMID:21102519
Roy, L D; Sahraei, M; Subramani, D B; Besmer, D; Nath, S; Tinder, T L; Bajaj, E; Shanmugam, K; Lee, Y Y; Hwang, S I L; Gendler, S J; Mukherjee, P
2011-03-24
Increased motility and invasiveness of pancreatic cancer cells are associated with epithelial to mesenchymal transition (EMT). Snai1 and Slug are zinc-finger transcription factors that trigger this process by repressing E-cadherin and enhancing vimentin and N-cadherin protein expression. However, the mechanisms that regulate this activation in pancreatic tumors remain elusive. MUC1, a transmembrane mucin glycoprotein, is associated with the most invasive forms of pancreatic ductal adenocarcinomas (PDA). In this study, we show that over expression of MUC1 in pancreatic cancer cells triggers the molecular process of EMT, which translates to increased invasiveness and metastasis. EMT was significantly reduced when MUC1 was genetically deleted in a mouse model of PDA or when all seven tyrosines in the cytoplasmic tail of MUC1 were mutated to phenylalanine (mutated MUC1 CT). Using proteomics, RT-PCR and western blotting, we revealed a significant increase in vimentin, Slug and Snail expression with repression of E-Cadherin in MUC1-expressing cells compared with cells expressing the mutated MUC1 CT. In the cells that carried the mutated MUC1 CT, MUC1 failed to co-immunoprecipitate with β-catenin and translocate to the nucleus, thereby blocking transcription of the genes associated with EMT and metastasis. Thus, functional tyrosines are critical in stimulating the interactions between MUC1 and β-catenin and their nuclear translocation to initiate the process of EMT. This study signifies the oncogenic role of MUC1 CT and is the first to identify a direct role of the MUC1 in initiating EMT during pancreatic cancer. The data may have implications in future design of MUC1-targeted therapies for pancreatic cancer.
NASA Astrophysics Data System (ADS)
Huo, Zongliang; Jin, Lei; Han, Yulong; Li, Xinkai; Ye, Tianchun; Liu, Ming
2015-01-01
The influence of post-deposition annealing (PDA) temperature condition on charge distribution behavior of HfO2 thin films was systematically investigated by various-temperature Kelvin probe force microscopy technology. Contact potential difference profiles demonstrated that charge storage capability shrinks with decreasing annealing temperature from 1,000 to 500 °C and lower. Compared to 1,000 °C PDA, it was found that 500 °C PDA causes deeper effective trap energy level, suppresses lateral charge spreading, and improves the retention characteristics. It is concluded that low-temperature PDA can be adopted in 3D HfO2-based charge trap flash memory to improve the thermal treatment compatibility of the bottom peripheral logic and upper memory arrays.
Duncan, Jennifer M; Janke, E Amy; Kozak, Andrea T; Roehrig, Megan; Russell, Stephanie W; McFadden, H Gene; Demott, Andrew; Pictor, Alex; Hedeker, Don; Spring, Bonnie
2011-04-11
Obese adults struggle to make the changes necessary to achieve even modest weight loss, though a decrease in weight by as little as 10% can have significant health benefits. Failure to meet weight loss goals may in part be associated with barriers to obesity treatment. Wide-spread dissemination of evidence-based obesity treatment faces multiple challenges including cost, access, and implementing the programmatic characteristics on a large scale. The PDA+: A Personal Digital Assistant for Obesity Treatment randomized controlled trial (RCT) was designed to test whether a PDA-based behavioral intervention enhances the effectiveness of the existing group weight loss treatment program at VA Medical Centers Managing Overweight/Obese Veterans Everywhere (MOVE!). We also aim to introduce technology as a way to overcome systemic barriers of traditional obesity treatment. Veterans enrolled in the MOVE! group at the Hines Hospital VAMC with BMI ≥ 25 and ≤ 40 and weigh < 400 pounds, experience chronic pain (≥ 4 on the NRS-I scale for ≥ 6 months prior to enrollment) and are able to participate in a moderate intensity exercise program will be recruited and screened for eligibility. Participants will be randomized to receive either: a) MOVE! treatment alone (Standard Care) or b) Standard Care plus PDA (PDA+). Those randomized to PDA+ will record dietary intake, physical activity, and weight on the PDA. In addition, they will also record mood and pain intensity, and receive biweekly telephone support for the first 6-months of the 12-month study. All participants will attend in-person lab sessions every three months to complete questionnaires and for the collection of anthropomorphic data. Weight loss and decrease in pain level intensity are the primary outcomes. The PDA+ trial represents an important step in understanding ways to improve the use of technology in obesity treatment. The trial will address barriers to obesity care by implementing effective behavioral components of a weight loss intervention and delivering high intensity, low cost obesity treatment. This RCT also tests an intervention approach supported by handheld technology in a population traditionally considered to have lower levels of technology literacy. ClinicalTrials.gov: NCT00371462.
Stabilization of beta-catenin induces pancreas tumor formation.
Heiser, Patrick W; Cano, David A; Landsman, Limor; Kim, Grace E; Kench, James G; Klimstra, David S; Taketo, Maketo M; Biankin, Andrew V; Hebrok, Matthias
2008-10-01
beta-Catenin signaling within the canonical Wnt pathway is essential for pancreas development. However, the pathway is normally down-regulated in the adult organ. Increased cytoplasmic and nuclear localization of beta-catenin can be detected in nearly all human solid pseudopapillary neoplasms (SPN), a rare tumor with low malignant potential. Conversely, pancreatic ductal adenocarcinoma (PDA) accounts for the majority of pancreatic tumors and is among the leading causes of cancer death. Whereas activating mutations within beta-catenin and other members of the canonical Wnt pathway are rare, recent reports have implicated Wnt signaling in the development and progression of human PDA. Here, we sought to address the role of beta-catenin signaling in pancreas tumorigenesis. Using Cre/lox technology, we conditionally activated beta-catenin in a subset of murine pancreatic cells in vivo. Activation of beta-catenin results in the formation of large pancreatic tumors at a high frequency in adult mice. These tumors resemble human SPN based on morphologic and immunohistochemical comparisons. Interestingly, stabilization of beta-catenin blocks the formation of pancreatic intraepithelial neoplasia (PanIN) in the presence of an activating mutation in Kras that is known to predispose individuals to PDA. Instead, mice in which beta-catenin and Kras are concurrently activated develop distinct ductal neoplasms that do not resemble PanIN lesions. These results demonstrate that activation of beta-catenin is sufficient to induce pancreas tumorigenesis. Moreover, they indicate that the sequence in which oncogenic mutations are acquired has profound consequences on the phenotype of the resulting tumor.
Milrinone use for hemodynamic instability in patent ductus arteriosus ligation.
Halliday, Matthew; Kavarana, Minoo; Ebeling, Myla; Kiger, James
2017-03-01
Determine if prophylactic milrinone improves cardiovascular or long-term clinical outcomes in preterm neonates who receive surgical patent ductus arteriosus (PDA) ligation. Retrospective review of 45 infants over a 4-year period that received a PDA ligation at one institution. Data were collected on morbidity and mortality outcomes for all infants as well as milrinone therapy perioperatively. Of the 45 infants that were studied 15 received milrinone in the perioperative period of PDA ligation and the remaining 30 infants did not receive milrinone. The use of milrinone showed no statistically significant improvement in acute markers of hemodynamic stability. There was also no statistically significant difference in morbidity and mortality outcomes in milrinone group compared to the non-milrinone group. Prophylactic milrinone use for premature infants following PDA ligation does not show a significant cardiovascular or long-term clinical benefit.
Patent Ductus Arteriosus Ligation and Adverse Outcomes: Causality or Bias?
Weisz, Dany E.; McNamara, Patrick J.
2014-01-01
Observational studies have associated patent ductus arteriosus (PDA) ligation in preterm infants with increased chronic lung disease (CLD), retinopathy of prematurity, and neurodevelopmental impairment at long-term follow-up. Although the biological rationale for this association is incompletely understood, there is an emerging secular trend toward a permissive approach to the PDA. However, insufficient adjustment for postnatal, pre-ligation confounders, such as intraventricular hemorrhage and the duration and intensity of mechanical ventilation, suggests the presence of residual bias due to confounding by indication, and obliges caution in interpreting the ligation-morbidity relationship. A period of conservative management after failure of medical PDA closure may be considered to reduce the number of infants treated with surgery. Increased mortality and CLD in infants with persistent symptomatic PDA suggests that surgical ligation remains an important treatment modality for preterm infants. PMID:25024972
Wall shear stress distributions on stented patent ductus arteriosus
NASA Astrophysics Data System (ADS)
Kori, Mohamad Ikhwan; Jamalruhanordin, Fara Lyana; Taib, Ishkrizat; Mohammed, Akmal Nizam; Abdullah, Mohammad Kamil; Ariffin, Ahmad Mubarak Tajul; Osman, Kahar
2017-04-01
A formation of thrombosis due to hemodynamic conditions after the implantation of stent in patent ductus arteriosus (PDA) will derived the development of re-stenosis. The phenomenon of thrombosis formation is significantly related to the distribution of wall shear stress (WSS) on the arterial wall. Thus, the aims of this study is to investigate the distribution of WSS on the arterial wall after the insertion of stent. Three dimensional model of patent ductus arteriosus inserted with different types of commercial stent are modelled. Computational modelling is used to calculate the distributions of WSS on the arterial stented PDA. The hemodynamic parameters such as high WSS and WSSlow are considered in this study. The result shows that the stented PDA with Type III stent has better hemodynamic performance as compared to others stent. This model has the lowest distributions of WSSlow and also the WSS value more than 20 dyne/cm2. From the observed, the stented PDA with stent Type II showed the highest distributions area of WSS more than 20 dyne/cm2. This situation revealed that the high possibility of atherosclerosis to be developed. However, the highest distribution of WSSlow for stented PDA with stent Type II indicated that high possibility of thrombosis to be formed. In conclusion, the stented PDA model calculated with the lowest distributions of WSSlow and WSS value more than 20dyne/cm2 are considered to be performed well in stent hemodynamic performance as compared to other stents.
Masdrakis, Vasilios G; Legaki, Emilia-Maria; Vaidakis, Nikolaos; Ploumpidis, Dimitrios; Soldatos, Constantin R; Papageorgiou, Charalambos; Papadimitriou, George N; Oulis, Panagiotis
2015-07-01
Increased heartbeat perception accuracy (HBP-accuracy) may contribute to the pathogenesis of Panic Disorder (PD) without or with Agoraphobia (PDA). Extant research suggests that HBP-accuracy is a rather stable individual characteristic, moreover predictive of worse long-term outcome in PD/PDA patients. However, it remains still unexplored whether HBP-accuracy adversely affects patients' short-term outcome after structured cognitive behaviour therapy (CBT) for PD/PDA. To explore the potential association between HBP-accuracy and the short-term outcome of a structured brief-CBT for the acute treatment of PDA. We assessed baseline HBP-accuracy using the "mental tracking" paradigm in 25 consecutive medication-free, CBT-naive PDA patients. Patients then underwent a structured, protocol-based, 8-session CBT by the same therapist. Outcome measures included the number of panic attacks during the past week, the Agoraphobic Cognitions Questionnaire (ACQ), and the Mobility Inventory-Alone subscale (MI-alone). No association emerged between baseline HBP-accuracy and posttreatment changes concerning number of panic attacks. Moreover, higher baseline HBP-accuracy was associated with significantly larger reductions in the scores of the ACQ and the MI-alone scales. Our results suggest that in PDA patients undergoing structured brief-CBT for the acute treatment of their symptoms, higher baseline HBP-accuracy is not associated with worse short-term outcome concerning panic attacks. Furthermore, higher baseline HBP-accuracy may be associated with enhanced therapeutic gains in agoraphobic cognitions and behaviours.
Ali, Safaa; El Sisi, Amel
2016-04-01
To assess the challenges, feasibility, and efficacy of device closure of patent ductus arteriosus (PDA) in small children weighing ⩽10 kg for different types of devices used in an initial experience at Sohag University hospital. Between March 2011 and September 2014, 91 patients with PDA underwent transcatheter closure in our institute, among whom 54 weighed ⩽10 kg. All of these patients underwent transcatheter closure of PDA using either a Cook Detachable Coil, PFM Nit-Occlud, or Amplatzer duct occluder. A retrospective review of the treatment results and adverse events was performed. Successful device placement was achieved in 53/54 small children (98.1%). The median minimum PDA diameter was 2.4 mm [interquartile range (IQR, 1.8-3.5 mm), median weight 8 kg (IQR, 7-10 kg), and median age 10 months (IQR, 8-17 months)]. Mild aortic obstruction occurred in one case (1.9%), as the device became displaced towards the aorta after release. The device embolized in one case (1.9%) and no retrieval attempt was made. Five cases (9.3%) had minor vascular complications. With the current availability of devices for PDA closure, transcatheter closure of PDA is considered safe and efficacious in small children weighing ⩽10 kg with good mid-term outcome. The procedure had a low rate of high-severity adverse events even with the initial experience of the catheterization laboratory.
Rapacciuolo, Antonio; Losi, Maria Angela; Borgia, Francesco; De Angelis, Maria Carmen; Esposito, Francesca; Cavallaro, Massimo; De Rosa, Roberta; Piscione, Federico; Chiariello, Massimo
2009-04-01
A 70-year-old man was admitted because of a 6-month history of progressive dyspnoea on exertion. The medical history showed that he suffered from patent ductus arteriosus (PDA) that was closed at 35 years of age by surgical ligation. Subsequently, up to year 1992, no evidence of residual left-to-right shunt was found. When he first came to our attention, we performed an echocardiographic test evidencing left ventricular dilation and contractile dysfunction and a recurrence of PDA. To exclude other possible causes of congestive heart failure, we performed several tests, including a coronary angiogram that showed coronary atherosclerosis without significant lesions. The haemodynamic study confirmed that the PDA was associated with a mild pulmonary hypertension with a QP: QS of 2: 1. The patient did not report any cardiovascular risk factor. Therefore, we concluded that PDA was responsible for congestive heart failure in this patient. We performed percutaneous closure of PDA, which was able to reverse left ventricular dilation and dysfunction, improving the patient's symptoms, at 1 month as well as 4 months after the interventional procedure. Although this kind of device is frequently used in the paediatric population, adult patients may present different challenges in proper management, such as poor visualization, calcification and pulmonary hypertension. In the description of the case reported here, we show that a PDA can present as congestive heart failure in the elderly. Percutaneous closure can be very effective in ameliorating left ventricular performance as well as symptoms.
Comparative analysis of pigments in red and yellow banana fruit.
Fu, Xiumin; Cheng, Sihua; Liao, Yinyin; Huang, Bingzhi; Du, Bing; Zeng, Wei; Jiang, Yueming; Duan, Xuewu; Yang, Ziyin
2018-01-15
Color is an important characteristic determining the fruit value. Although ripe bananas usually have yellow peels, several banana cultivars have red peels. As details of the pigments in banana fruits are unknown, we investigated these pigments contents and compositions in the peel and pulp of red cultivar 'Hongjiaowang' and yellow cultivar 'Baxijiao' by UPLC-PDA-QTOF-MS and HPLC-PDA techniques. The 'Hongjiaowang' peel color was mainly determined by the presence of anthocyanin-containing epidermal cells. Rutinoside derivatives of cyanidin, peonidin, petunidin, and malvidin were unique to the red peel, and possibly responsible for the red color. 'Hongjiaowang' contained higher total content of carotenoids than 'Baxijiao' in both pulp and peel. Lutein, α-carotene, and β-carotene were main carotenoids, which might play a more important role than flavonoids in producing the yellow banana color owing to the properties and distribution in the fruit. The information will help us understand a complete profile of pigments in banana. Copyright © 2017 Elsevier Ltd. All rights reserved.
Polydiacetylenyl β-cyclodextrin based smart vesicles for colorimetric assay of arginine and lysine
NASA Astrophysics Data System (ADS)
Cho, Eunae; Kim, Hwanhee; Choi, Youngjin; Paik, Seung R.; Jung, Seunho
2016-08-01
Selective visualization of arginine and lysine has been explored among 20 amino acids using the hybrid conjugate of β-cyclodextrin (β-CD) and polydiacetylene (PDA). The mono pentacosa-10,12-diynyl aminomethyl group was successfully coupled to either the primary or the secondary face of β-CD, where mono-6-amino-6-deoxy-β-CD or mono-3-amino-3-deoxy-β-CD reacted with the N-hydroxysuccinimide ester of 10,12-pentacosadiynoic acid. In this combinatorial system, the cylindrical β-cyclodextrin functions as a channel for the introduction of the cationic amino acids to the artificial membrane. The membrane perturbation and aggregation by the target amino acids could be exclusively visualized as a blue to red color change based on the responsive polydiacetylene domain. These interesting findings demonstrated that the developed β-CD conjugated PDA system may offer a new method of cell-penetrating mechanism, a promising vector system, as well as impact the production industry of arginine or lysine.
Trisomy 15 mosaicism and uniparental disomy (UPD) in a liveborn infant
DOE Office of Scientific and Technical Information (OSTI.GOV)
Milunsky, J.M.; Wyandt, H.E.; Amos, J.A.
We describe a liveborn infant with UPD in association with trisomy 15 mosaicism. Third trimester amniocentesis was performed for suspected IUGR. Results revealed 46,XX/47,XX,+15. The infant initially had respiratory distress and fed poorly. Symmetrical growth retardation, craniofacial dysmorphism, excess nuchal folds, a heart murmur, hypermobile joints, minor limb abnormalities, absent spontaneous movement and an abnormal cry were noted. Further study showed complex heart defects, including VSD and PDA, a left choroid plexus cyst, 13 ribs bilaterally, abnormal optic discs, abnormal visual evoked potentials and abnormal auditory brain stem responses. The infant died at 6 weeks of life from cardio-respiratory complications.more » Blood chromosomes were normal, 46,XX in 100 cells. Parental blood chromosomes were normal. Skin biopsy revealed 46,XX/47,XX,+15 in 40/50 (80%) cells as did autopsy lung tissue. Molecular analysis of the infant`s blood revealed maternal uniparental heterodisomy for chromosome 15 in the 46,XX cell line. Microsatellite analysis demonstrated that the extra chromosome originated from a maternal meiosis I nondisjunction. To our knowledge, this is the first liveborn infant with mosaic trisomy 15 and UPD in the diploid cells. Trisomy 15, heretofore, has been regarded as nonviable, even in mosaic form. While maternal UPD is associated with the Prader-Willi syndrome phenotype, mosaicism for trisomy 15 has been reported only when confined to the placenta. UPD in this case generally complicated prediction of the phenotype and raises the question whether all cases with UPD 15 should have more than one tissue studied to determine undetected trisomy 15.« less
2013-01-01
Background Patent ductus arteriosus (PDA) is one of the commonest congenital heart diseases that require closure within the first few months after birth. The residential area of patients affects the size of the PDA: living in highlands, like most places in Ethiopia, is a risk for having larger sized PDA. Closure of these congenital heart defects is usually performed at an early age in places where capable centers are available. In Ethiopia, closure of these defects is done on mission basis often at an older age. Recently, limited reports came about the occurrence of postoperative left ventricular systolic dysfunction (POLVD) following closure of PDA though full explanation is still lacking. Objective To determine the rate of and time to improvement of POLVD and the factors associated with it in children and adolescents who underwent surgical closure of PDA. Method All children and adolescents who underwent surgical closure of PDA at the Cardiac Center, Ethiopia (CCE) had postoperative follow up with echocardiography. Serial left ventricular ejection fraction (LVEF) and fiber shortening (FS) values were recorded for all of them. SPSS 20 was used to analyze the data. Results A total of 36 children and adolescents who underwent surgical closure of PDA from January 2009 to December 2012 and who fulfilled the inclusion criteria were studied. Their mean age at intervention was 8.52 years (SD = 5.23 years), 77.80% were females. The mean duct size as determined by either echocardiography or intra-operative by the surgeon was 10.31 mm (SD = 3.20 mm). They were followed for a mean duration of 24.80 months (SD = 12.36 months) following surgical closure of PDA. The mean LVEF and FS decreased from 65.06% and 35.28% preoperatively to 54.83% and 28.40% post-operatively respectively. Fifteen (42.86%) of the patients had a post-operative LVEF of less than 55%. The mean time to normalization of systolic function was 5.11 weeks (SD = 3.30 weeks). Having an associated cardiac lesion was an independent predictor of POLVD. Conclusions We conclude that there is a high rate of POLVD following surgical closure of large PDA in highlanders. We recommend a serial and systematic follow up of these children postoperatively. Those with a significant cardiac dysfunction may need cardiac medications like Angiotensin Converting Enzyme Inhibitors (ACEI). PMID:23721219
Chipinda, Itai; Mbiya, Wilbes; Adigun, Risikat Ajibola; Morakinyo, Moshood K.; Law, Brandon F.; Simoyi, Reuben H.; Siegel, Paul D.
2015-01-01
Chemical allergens bind directly, or after metabolic or abiotic activation, to endogenous proteins to become allergenic. Assessment of this initial binding has been suggested as a target for development of assays to screen chemicals for their allergenic potential. Recently we reported a nitrobenzenethiol (NBT) based method for screening thiol reactive skin sensitizers, however, amine selective sensitizers are not detected by this assay. In the present study we describe an amine (pyridoxylamine (PDA)) based kinetic assay to complement the NBT assay for identification of amine-selective and non-selective skin sensitizers. UV-Vis spectrophotometry and fluorescence were used to measure PDA reactivity for 57 chemicals including anhydrides, aldehydes, and quinones where reaction rates ranged from 116 to 6.2 × 10−6 M−1 s−1 for extreme to weak sensitizers, respectively. No reactivity towards PDA was observed with the thiol-selective sensitizers, non-sensitizers and prohaptens. The PDA rate constants correlated significantly with their respective murine local lymph node assay (LLNA) threshold EC3 values (R2 = 0.76). The use of PDA serves as a simple, inexpensive amine based method that shows promise as a preliminary screening tool for electrophilic, amine-selective skin sensitizers. PMID:24333919
A survey of personal digital assistant use in a sample of New Zealand doctors.
Menzies, Oliver H; Thwaites, John
2012-03-30
To gather information about handheld computing hardware and software usage by hospital based doctors in New Zealand (NZ). An online tool (SurveyMonkey) was used to conduct the survey from 27 June to 10 September 2010. Distribution of the survey was via an email to all NZ District Health Boards (DHBs). There were 850 responses. About half of respondents (52%) used a personal digital assistant (PDA), 90% using it at least once daily. Usage varied greatly between DHBs (27-100%), perhaps related to institutional support. Among PDA users, the most common applications were the non-clinical; Scheduler (95%), Contacts (97%), and Tasks (83%). Users felt PDAs helped considerably with organisation and time saving. For non-users there were a range of barriers to usage, cost being a large factor. Another major barrier identified by both users and non-users was lack of organisational integration and support. Half of survey respondents used a PDA. PDA usage of responders from different DHBs varied considerably. Perceived barriers to PDA use included cost and lack of institutional support. A collaborative approach between clinical leadership and Information Technology teams to address barriers may result in increased utility and usage of PDAs in the NZ health system.
Degradation of phorbol 12,13-diacetate in aqueous solution by gamma irradiation
NASA Astrophysics Data System (ADS)
Kongmany, Santi; Furuta, Masakazu; Matsuura, Hiroto; Okuda, Shuichi; Imamura, Kiyoshi; Maeda, Yasuaki
2014-12-01
Phorbol esters (PEs) are highly toxic compounds that cause skin irritation, inflammation, and tumor promotion upon contact with humans or animals. These compounds are naturally present in Jatropha curcas L. To promote the use of J. curcas seed oil in bio-diesel production industries and reduce environmental concerns, it is necessary to find methods of degrading PEs. In this study, the degradation of phorbol 12,13-diacetate (PDA), as a representative PE, in aqueous solution at a concentration of 10 mg/L by 60Co-γ-irradiation was investigated. The results demonstrate that PDA was effectively degraded by this treatment and the degradation efficiency increased with the absorbed dose within the range of 0.5-3 kGy. Complete degradation of PDA was achieved at a dose of 3 kGy. In the presence of radical scavengers (i.e., methanol, tert-butanol, 2-propanol), reactive species from water radiolysis were scavenged, and significant inhibition of PDA degradation was observed at absorbed doses less than 1 kGy. In the presence of nitrous oxide, the generation of hydroxyl radicals (rad OH) was promoted during gamma irradiation and PDA degradation was drastically enhanced.
NASA Astrophysics Data System (ADS)
Wang, Xinglu; Qin, Xiaoye; Wang, Wen; Liu, Yue; Shi, Xiaoran; Sun, Yong; Liu, Chen; Zhao, Jiali; Zhang, Guanhua; Liu, Hui; Cho, Kyeongjae; Wu, Rui; Wang, Jiaou; Zhang, Sen; Wallace, Robert M.; Dong, Hong
2018-06-01
A systematic study of the interfacial chemistry for the HCl pretreated and native oxide InAs(100) samples upon atomic layer deposition (ALD) of Al2O3, and the post deposition annealing (PDA) process has been carried out, using in situ synchrotron radiation photoelectron spectroscopy. The "clean up" effect for the native oxide sample is detected, but it is not observed for the HCl pretreated sample. The out-diffusion and desorption of both In and As oxides have been characterized during the ALD process and the following PDA process. The surface morphology evolution during the PDA process is studied by in situ photo-emission electron microscopy. The bubbles emerged after PDA at 360 °C and grew up at 370 °C. After PDA at 400 °C and at higher temperatures, pits are seen in some areas, and the tear up of the Al2O3 film is seen in other areas with the formation of indium droplets. This study gives insight in the mechanism of elemental diffusion/desorption, which may associate the reliability of III-V semiconductor based devices.
Effect of palladium doping on the stability and fragmentation patterns of cationic gold clusters
NASA Astrophysics Data System (ADS)
Ferrari, P.; Hussein, H. A.; Heard, C. J.; Vanbuel, J.; Johnston, R. L.; Lievens, P.; Janssens, E.
2018-05-01
We analyze in detail how the interplay between electronic structure and cluster geometry determines the stability and the fragmentation channels of single Pd-doped cationic Au clusters, PdA uN-1+ (N =2 -20 ). For this purpose, a combination of photofragmentation experiments and density functional theory calculations was employed. A remarkable agreement between the experiment and the calculations is obtained. Pd doping is found to modify the structure of the Au clusters, in particular altering the two-dimensional to three-dimensional transition size, with direct consequences on the stability of the clusters. Analysis of the electronic density of states of the clusters shows that depending on cluster size, Pd delocalizes one 4 d electron, giving an enhanced stability to PdA u6 + , or remains with all 4 d10 electrons localized, closing an electronic shell in PdA u9 + . Furthermore, it is observed that for most clusters, Au evaporation is the lowest-energy decay channel, although for some sizes Pd evaporation competes. In particular, PdA u7 + and PdA u9 + decay by Pd evaporation due to the high stability of the A u7 + and A u9 + fragmentation products.
Bayesian extraction of the parton distribution amplitude from the Bethe-Salpeter wave function
NASA Astrophysics Data System (ADS)
Gao, Fei; Chang, Lei; Liu, Yu-xin
2017-07-01
We propose a new numerical method to compute the parton distribution amplitude (PDA) from the Euclidean Bethe-Salpeter wave function. The essential step is to extract the weight function in the Nakanishi representation of the Bethe-Salpeter wave function in Euclidean space, which is an ill-posed inversion problem, via the maximum entropy method (MEM). The Nakanishi weight function as well as the corresponding light-front parton distribution amplitude (PDA) can be well determined. We confirm prior work on PDA computations, which was based on different methods.
Development of autoclave moldable addition-type polyimides
NASA Technical Reports Server (NTRS)
Vaughan, R. W.; Jones, R. J.; Orell, M. K.; Zakrzewski, G. A.
1976-01-01
Chemistry and processing modifications of the poly(Diels Alder) polyimide (PDA) resin were performed to obtain structural composites suitable for 589 K (600 F) service. This work demonstrated that the PDA resin formulation is suitable for service at 589 K (600 F) for up to 125 hours when used in combination with Hercules HTS graphite fiber. Sandwich panels were autoclave molded using PDA/HTS skins and polyimide/glass honeycomb core. Excellent adhesion between honeycomb core and the facing skins was demonstrated. Fabrication ease was demonstrated by autoclave molding three-quarter scale YF-12 wing panels.
Jan, S-L; Hwang, B; Fu, Y-C; Chi, C-S
2005-01-01
The Amplatzer duct occluder (ADO) provides a safe and effective therapy for patients with moderate- to large-sized patent ductus arteriosus (PDA), but there have been few reports of transcatheter closure of very large PDAs in young children and infants. We report a successful transcatheter closure of a very large PDA, 10.5 mm in diameter at the narrowest point, with a 14/12-mm ADO. To our knowledge, this is the largest PDA ever closed by an interventional method in such a young child.
Automated Percentage of Breast Density Measurements for Full-field Digital Mammography Applications.
Fowler, Erin E E; Vachon, Celine M; Scott, Christopher G; Sellers, Thomas A; Heine, John J
2014-08-01
Increased mammographic breast density is a significant risk factor for breast cancer. A reproducible, accurate, and automated breast density measurement is required for full-field digital mammography (FFDM) to support clinical applications. We evaluated a novel automated percentage of breast density measure (PDa) and made comparisons with the standard operator-assisted measure (PD) using FFDM data. We used a nested breast cancer case-control study matched on age, year of mammogram and diagnosis with images acquired from a specific direct x-ray conversion FFDM technology. PDa was applied to the raw and clinical display (or processed) representation images. We evaluated the transformation (pixel mapping) of the raw image, giving a third representation (raw-transformed), to improve the PDa performance using differential evolution optimization. We applied PD to the raw and clinical display images as a standard for measurement comparison. Conditional logistic regression was used to estimate the odd ratios (ORs) for breast cancer with 95% confidence intervals (CI) for all measurements; analyses were adjusted for body mass index. PDa operates by evaluating signal-dependent noise (SDN), captured as local signal variation. Therefore, we characterized the SDN relationship to understand the PDa performance as a function of data representation and investigated a variation analysis of the transformation. The associations of the quartiles of operator-assisted PD with breast cancer were similar for the raw (OR: 1.00 [ref.]; 1.59 [95% CI, 0.93-2.70]; 1.70 [95% CI, 0.95-3.04]; 2.04 [95% CI, 1.13-3.67]) and clinical display (OR: 1.00 [ref.]; 1.31 [95% CI, 0.79-2.18]; 1.14 [95% CI, 0.65-1.98]; 1.95 [95% CI, 1.09-3.47]) images. PDa could not be assessed on the raw images without preprocessing. However, PDa had similar associations with breast cancer when assessed on 1) raw-transformed (OR: 1.00 [ref.]; 1.27 [95% CI, 0.74-2.19]; 1.86 [95% CI, 1.05-3.28]; 3.00 [95% CI, 1.67-5.38]) and 2) clinical display (OR: 1.00 [ref.]; 1.79 [95% CI, 1.04-3.11]; 1.61 [95% CI, 0.90-2.88]; 2.94 [95% CI, 1.66-5.19]) images. The SDN analysis showed that a nonlinear relationship between the mammographic signal and its variation (ie, the biomarker for the breast density) is required for PDa. Although variability in the transform influenced the respective PDa distribution, it did not affect the measurement's association with breast cancer. PDa assessed on either raw-transformed or clinical display images is a valid automated breast density measurement for a specific FFDM technology and compares well against PD. Further work is required for measurement generalization. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.
Randomized controlled trial of a patient decision-making aid for orthodontics.
Parker, Kate; Cunningham, Susan J; Petrie, Aviva; Ryan, Fiona S
2017-08-01
Patient decision-making aids (PDAs) are instruments that facilitate shared decision making and enable patients to reach informed, individual decisions regarding health care. The objective of this study was to assess the efficacy of a PDA compared with traditional information provision for adolescent patients considering fixed appliance orthodontic treatment. Before treatment, orthodontic patients were randomly allocated into 2 groups: the intervention group received the PDA and standard information regarding fixed appliances, and the control group received the standard information only. Decisional conflict was measured using the Decisional Conflict Scale, and the levels of decisional conflict were compared between the 2 groups. Seventy-two patients were recruited and randomized in a ratio of 1:1 to the PDA and control groups. Seventy-one patients completed the trial (control group, 36; PDA group, 35); this satisfied the sample size calculation. The median total Decisional Conflict Scale score in the PDA group was lower than in the control group (15.63 and 19.53, respectively). However, this difference was not statistically significant (difference between groups, 3.90; 95% confidence interval of the difference, -4.30 to 12.11). Sex, ethnicity, age, and the time point at which patients were recruited did not have significant effects on Decisional Conflict Scale scores. No harm was observed or reported for any participant in the study. The results of this study showed that the provision of a PDA to adolescents before they consented for fixed appliances did not significantly reduce decisional conflict. There may be a benefit in providing a PDA for some patients, but it is not yet possible to say how these patients could be identified. This trial was registered with the Harrow National Research Ethics Committee (reference 12/LO/0279). The protocol was not published before trial commencement. Copyright © 2017. Published by Elsevier Inc.
Murphy, Thomas; Schwedock, Julie; Nguyen, Kham; Mills, Anna; Jones, David
2015-01-01
New recommendations for the validation of rapid microbiological methods have been included in the revised Technical Report 33 release from the PDA. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This case study applies those statistical methods to accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological methods system being evaluated for water bioburden testing. Results presented demonstrate that the statistical methods described in the PDA Technical Report 33 chapter can all be successfully applied to the rapid microbiological method data sets and gave the same interpretation for equivalence to the standard method. The rapid microbiological method was in general able to pass the requirements of PDA Technical Report 33, though the study shows that there can be occasional outlying results and that caution should be used when applying statistical methods to low average colony-forming unit values. Prior to use in a quality-controlled environment, any new method or technology has to be shown to work as designed by the manufacturer for the purpose required. For new rapid microbiological methods that detect and enumerate contaminating microorganisms, additional recommendations have been provided in the revised PDA Technical Report No. 33. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This paper applies those statistical methods to analyze accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological method system being validated for water bioburden testing. The case study demonstrates that the statistical methods described in the PDA Technical Report No. 33 chapter can be successfully applied to rapid microbiological method data sets and give the same comparability results for similarity or difference as the standard method. © PDA, Inc. 2015.
Frontal cortex absolute beta power measurement in Panic Disorder with Agoraphobia patients.
de Carvalho, Marcele Regine; Velasques, Bruna Brandão; Freire, Rafael C; Cagy, Maurício; Marques, Juliana Bittencourt; Teixeira, Silmar; Thomaz, Rafael; Rangé, Bernard P; Piedade, Roberto; Akiskal, Hagop Souren; Nardi, Antonio Egidio; Ribeiro, Pedro
2015-09-15
Panic disorder patients are hypervigilant to danger cues and highly sensitive to unpredictable aversive events, what leads to anticipatory anxiety, that is one key component of the disorder maintenance. Prefrontal cortex seems to be involved in these processes and beta band activity may be related to the involvement of top-down processing, whose function is supposed to be disrupted in pathological anxiety. The objective of this study was to measure frontal absolute beta-power (ABP) with qEEG in panic disorder and agoraphobia (PDA) patients compared to healthy controls. qEEG data were acquired while participants (24 PDA patients and 21 controls) watched a computer simulation (CS), consisting of moments classified as "high anxiety" (HAM) and "low anxiety" (LAM). qEEG data were also acquired during two rest conditions, before and after the computer simulation display. The statistical analysis was performed by means of a repeated measure analysis of variance (two-way ANOVA) and ABP was the dependent variable of interest. The main hypothesis was that a higher ABP in PDA patients would be found related to controls. Moreover, in HAM the ABP would be different than in LAM. the main finding was an interaction between the moment and group for the electrodes F7, F8, Fp1 and Fp2. We observed a higher ABP in PDA patients when compared to controls while watching the CS. The higher beta-power in the frontal cortex for the PDA group may reflect a state of high excitability, together with anticipatory anxiety and maintenance of hypervigilant cognitive state. our results suggest a possible deficiency in top-down processing reflected by a higher ABP in the PDA group while watching the CS and they highlight the recruitment of prefrontal regions during the exposure to anxiogenic stimuli. the small sample, the wide age range of participants and the use of psychotropic medications by most of the PDA patients. Copyright © 2015 Elsevier B.V. All rights reserved.
Zhang, Yunlin; Liu, Xiaohan; Osburn, Christopher L; Wang, Mingzhu; Qin, Boqiang; Zhou, Yongqiang
2013-01-01
CDOM biogeochemical cycle is driven by several physical and biological processes such as river input, biogeneration and photobleaching that act as primary sinks and sources of CDOM. Watershed-derived allochthonous (WDA) and phytoplankton-derived autochthonous (PDA) CDOM were exposed to 9 days of natural solar radiation to assess the photobleaching response of different CDOM sources, using absorption and fluorescence (excitation-emission matrix) spectroscopy. Our results showed a marked decrease in total dissolved nitrogen (TDN) concentration under natural sunlight exposure for both WDA and PDA CDOM, indicating photoproduction of ammonium from TDN. In contrast, photobleaching caused a marked increase in total dissolved phosphorus (TDP) concentration for both WDA and PDA CDOM. Thus TDN:TDP ratios decreased significantly both for WDA and PDA CDOM, which partially explained the seasonal dynamic of TDN:TDP ratio in Lake Taihu. Photobleaching rate of CDOM absorption a(254), was 0.032 m/MJ for WDA CDOM and 0.051 m/MJ for PDA CDOM from days 0-9, indicating that phototransformations were initially more rapid for the newly produced CDOM from phytoplankton than for the river CDOM. Extrapolation of these values to the field indicated that 3.9%-5.1% CDOM at the water surface was photobleached and mineralized every day in summer in Lake Taihu. Photobleaching caused the increase of spectral slope, spectral slope ratio and molecular size, indicating the CDOM mean molecular weight decrease which was favorable to further microbial degradation of mineralization. Three fluorescent components were validated in parallel factor analysis models calculated separately for WDA and PDA CDOM. Our study suggests that the humic-like fluorescence materials could be rapidly and easily photobleached for WDA and PDA CDOM, but the protein-like fluorescence materials was not photobleached and even increased from the transformation of the humic-like fluorescence substance to the protein-like fluorescence substance. Photobleaching was an important driver of CDOM and nutrients biogeochemistry in lake water.
Zhang, Yunlin; Liu, Xiaohan; Osburn, Christopher L.; Wang, Mingzhu; Qin, Boqiang; Zhou, Yongqiang
2013-01-01
CDOM biogeochemical cycle is driven by several physical and biological processes such as river input, biogeneration and photobleaching that act as primary sinks and sources of CDOM. Watershed-derived allochthonous (WDA) and phytoplankton-derived autochthonous (PDA) CDOM were exposed to 9 days of natural solar radiation to assess the photobleaching response of different CDOM sources, using absorption and fluorescence (excitation-emission matrix) spectroscopy. Our results showed a marked decrease in total dissolved nitrogen (TDN) concentration under natural sunlight exposure for both WDA and PDA CDOM, indicating photoproduction of ammonium from TDN. In contrast, photobleaching caused a marked increase in total dissolved phosphorus (TDP) concentration for both WDA and PDA CDOM. Thus TDN∶TDP ratios decreased significantly both for WDA and PDA CDOM, which partially explained the seasonal dynamic of TDN∶TDP ratio in Lake Taihu. Photobleaching rate of CDOM absorption a(254), was 0.032 m/MJ for WDA CDOM and 0.051 m/MJ for PDA CDOM from days 0–9, indicating that phototransformations were initially more rapid for the newly produced CDOM from phytoplankton than for the river CDOM. Extrapolation of these values to the field indicated that 3.9%–5.1% CDOM at the water surface was photobleached and mineralized every day in summer in Lake Taihu. Photobleaching caused the increase of spectral slope, spectral slope ratio and molecular size, indicating the CDOM mean molecular weight decrease which was favorable to further microbial degradation of mineralization. Three fluorescent components were validated in parallel factor analysis models calculated separately for WDA and PDA CDOM. Our study suggests that the humic-like fluorescence materials could be rapidly and easily photobleached for WDA and PDA CDOM, but the protein-like fluorescence materials was not photobleached and even increased from the transformation of the humic-like fluorescence substance to the protein-like fluorescence substance. Photobleaching was an important driver of CDOM and nutrients biogeochemistry in lake water. PMID:24204852
NASA Astrophysics Data System (ADS)
Li, Jian-Hua; Ni, Xing-Xing; Zhang, De-Bin; Zheng, Hui; Wang, Jia-Bin; Zhang, Qi-Qing
2018-06-01
A facile and versatile approach for the preparation of super-hydrophilic, excellent antifouling and hemocompatibility membranes had been developed through the generation in situ of bio-inspired polydopamine (PDA) microspheres on PVDF membranes. SEM images showed that the PDA microspheres were uniformly dispersed on the upper surface and the lower surface of the modified membranes. And there were a great number of PDA microspheres immobilized on the cross-section, but the interconnected pores structure was not destroyed. These facts indicated the existence of membrane micro-reactor effect for the whole membrane structure. Considering the remarkable improvement of hydrophilicity, antifouling properties, and permeation fluxes, we also proposed the cluster phenolic hydroxyl effect for the PVDF/PDA hybrid membranes. And the cluster phenolic hydroxyl effect can be ascribed to the all directions distributed phenolic hydroxyl groups on the whole membrane structure. Besides, the self-driven filtration experiments showed the great wetting ability and permeability of the PVDF/PDA hybrid membranes in filtration process without any external pressure. This implied the existence of accelerating self-driven force after the water flow flowed into the internal of membranes, which contributed to the increase of water flow velocity. All the three aspects were in favor of the enhancement of hydrophilicity, antifouling properties and permeability of the modified membranes. Moreover, the conventional filtration tests, oil/water emulsion filtration tests and protein adsorption tests were also carried out to discuss the practical applications of PVDF/PDA hybrid membranes. And the hemocompatibility of the modified membranes was also proved to enhance greatly through the hemolysis tests and platelet adhesion tests, indicating that the membranes were greatly promising in biomedical applications. The strategy of material modification reported here is substrate-independent and can be extended to other substrate materials, and allows the development of novel functional membranes through secondary treatments.
Eerola, Anneli; Jokinen, Eero; Boldt, Talvikki; Pihkala, Jaana
2006-03-07
We aimed to evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) hemodynamics. Today, most PDAs are closed percutaneously. Little is known, however, about hemodynamic changes after the procedure. Of 37 children (ages 0.6 to 10.6 years) taken to the catheterization laboratory for percutaneous PDA closure, the PDA was closed in 33. Left ventricular diastolic and systolic dimensions, volumes, and function were examined by two-dimensional (2D) and three-dimensional (3D) echocardiography and serum concentrations of natriuretic peptides measured before PDA closure, on the following day, and 6 months thereafter. Control subjects comprised 36 healthy children of comparable ages. At baseline, LV diastolic diameter measured >+2 SD in 5 of 33 patients. In 3D echocardiography, a median LV diastolic volume measured 54.0 ml/m2 in the control subjects and 58.4 ml/m2 (p < 0.05) in the PDA group before closure and 57.2 ml/m2 (p = NS) 6 months after closure. A median N-terminal brain natriuretic peptide (pro-BNP) concentration measured 72 ng/l in the control group and 141 ng/l in the PDA group before closure (p = 0.001) and 78.5 ng/l (p = NS) 6 months after closure. Patients differed from control subjects in indices of LV systolic and diastolic function at baseline. By the end of follow-up, all these differences had disappeared. Even in the subgroup of patients with normal-sized LV at baseline, the LV diastolic volume decreased significantly during follow-up. Changes in LV volume and function caused by PDA disappear by 6 months after percutaneous closure. Even the children with normal-sized LV benefit from the procedure.
PECVD based silicon oxynitride thin films for nano photonic on chip interconnects applications.
Sharma, Satinder K; Barthwal, Sumit; Singh, Vikram; Kumar, Anuj; Dwivedi, Prabhat K; Prasad, B; Kumar, Dinesh
2013-01-01
Thin silicon oxynitride (SiO(x)N(y)) films were deposited by low temperature (~300°C) plasma enhanced chemical vapour deposition (PECVD), using SiH(4), N(2)O, NH(3) precursor of the flow rate 25, 100, 30 sccm and subjected to the post deposition annealing (PDA) treatment at 400°C and 600°C for nano optical/photonics on chip interconnects applications. AFM result reveals the variation of roughness from 60.9 Å to 23.4 Å after PDA treatment with respect to the as-deposited films, favourable surface topography for integrated waveguide applications. A model of decrease in island height with the effect of PDA treatment is proposed in support of AFM results. Raman spectroscopy and FTIR measurements are performed in order to define the change in crystallite and chemical bonding of as-deposited as well as PDA treated samples. These outcomes endorsed to the densification of SiO(x)N(y) thin films, due to decrease in Si-N and Si-O bonds strain, as well the O-H, N-H bonds with in oxynitride network. The increase in refractive index and PL intensity of as deposited SiO(x)N(y) thin films to the PDA treated films at 400°C and 600°C are observed. The significant shift of PL spectra peak positions indicate the change in cluster size as the result of PDA treatment, which influence the optical properties of thin films. It might be due to out diffusion of hydrogen containing species from silicon oxynitride films after PDA treatment. In this way, the structural and optical, feasibility of SiO(x)N(y) films are demonstrated in order to obtain high quality thin films for nano optical/photonics on chip interconnects applications. Copyright © 2012 Elsevier Ltd. All rights reserved.
Molva, Celenk; Baysal, Ayse Handan
2015-05-04
The present study examined the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 vegetative cells and spores after inoculation into apple, pomegranate and pomegranate-apple blend juices (10, 20, 40 and 80%, v/v). Also, the effect of sporulation medium was tested using mineral [Bacillus acidoterrestris agar (BATA) and Bacillus acidocaldarius agar (BAA)] and non-mineral containing media [potato dextrose agar (PDA) and malt extract agar (MEA)]. The juice samples were inoculated separately with approximately 10(5)CFU/mL cells or spores from different sporulation media and then incubated at 37°C for 336 h. The number of cells decreased significantly with increasing pomegranate juice concentration in the blend juices and storage time (p<0.001). Based on the results, 3.17, 3.53, and 3.72 log cell reductions were observed in 40%, 80% blend and pomegranate juices, respectively while the cell counts attained approximately 7.17 log CFU/mL in apple juice after 336 h. On the other hand, the cell growth was inhibited for a certain time, and then the numbers started to increase after 72 and 144 h in 10% and 20% blend juices, respectively. After 336 h, total population among spores produced on PDA, BATA, BAA and MEA indicated 1.49, 1.65, 1.67, and 1.28 log reductions in pomegranate juice; and 1.51, 1.38, 1.40 and 1.16 log reductions in 80% blend juice, respectively. The inhibitory effects of 10%, 20% and 40% blend juices varied depending on the sporulation media used. The results obtained in this study suggested that pomegranate and pomegranate-apple blend juices could inhibit the growth of A. acidoterrestris DSM 3922 vegetative cells and spores. Copyright © 2015 Elsevier B.V. All rights reserved.
Pion distribution amplitude from lattice QCD.
Cloët, I C; Chang, L; Roberts, C D; Schmidt, S M; Tandy, P C
2013-08-30
A method is explained through which a pointwise accurate approximation to the pion's valence-quark distribution amplitude (PDA) may be obtained from a limited number of moments. In connection with the single nontrivial moment accessible in contemporary simulations of lattice-regularized QCD, the method yields a PDA that is a broad concave function whose pointwise form agrees with that predicted by Dyson-Schwinger equation analyses of the pion. Under leading-order evolution, the PDA remains broad to energy scales in excess of 100 GeV, a feature which signals persistence of the influence of dynamical chiral symmetry breaking. Consequently, the asymptotic distribution φπ(asy)(x) is a poor approximation to the pion's PDA at all such scales that are either currently accessible or foreseeable in experiments on pion elastic and transition form factors. Thus, related expectations based on φ φπ(asy)(x) should be revised.
Cousineau, Héloïse; Marchand, André; Bouchard, Stéphane; Bélanger, Claude; Gosselin, Patrick; Langlois, Frédéric; Labrecque, Joane; Dugas, Michel J; Belleville, Geneviève
2016-04-01
Patients with panic disorder with agoraphobia (PDA) or generalized anxiety disorder (GAD) frequently also suffer from insomnia. However, the impact of cognitive-behavioral therapy (CBT) for anxiety disorders on insomnia has been understudied. Furthermore, comorbidity between anxiety disorders is common. Our main objective was to assess the impact of CBT for PDA or GAD on insomnia. In a quasi-experimental design, 86 participants with PDA and GAD received conventional CBT for their primary disorder or combined CBT for both disorders. Overall, CBTs had a significant impact on reducing insomnia symptoms (η = 0.58). However, among people with insomnia at pretest (67%), 33% still had an insomnia diagnosis, and the majority (63%) had clinically significant residual insomnia following treatment. In conclusion, the CBTs had a positive effect on the reduction of insomnia, but a significant proportion of participants still had insomnia problems following treatment. Clinicians should address insomnia during CBT for PDA and GAD.
Torre, D M; Sebastian, J L; Simpson, D E
2005-09-01
Cardiac auscultation is an important skill for medical students to master but students' exposure to cardiac auscultation is often unmonitored. The objective of this study was to gather data at the point of care about students' cardiac auscultation experience on a required medicine rotation using a Personal Digital Assistant (PDA) 'murmur form'. During an eight-month period, 120 M3 students used the authors' PDA-based learning tool to record information on 940 heart sounds and murmurs. Some 93% of all heart sounds/murmurs reported by students were verified by either a faculty member (56%) or a supervising resident (43%). A PDA can be a useful tool to monitor students' experiences of cardiac auscultation and to track direct observation of such skills by faculty or residents. Medical students are eager to use technology at the point of care to practice their clinical skills.
Paracetamol treatment of patent ductus arteriosus in preterm infants.
Nadir, E; Kassem, E; Foldi, S; Hochberg, A; Feldman, M
2014-10-01
To determine the effectiveness of paracetamol in closing patent ductus arteriosus (PDA) in preterm infants of our population. Infants with symptomatic PDA who failed or could not get ibuprofen treatment, and who were candidates for surgical ligation, were administered oral paracetamol 15 mg kg⁻¹ every 6h, for up to 7 days and were monitored for clinical, echocardiographic and laboratorial courses. Seven infants, between 24-27 weeks' gestation, were included. In four the DA was closed while treated by paracetamol-in one of them the DA reopened, treated with paracetamol again, and closed. In one infant, the DA almost closed, symptoms disappeared, and the DA subsequently closed spontaneously later. Two needed surgical ligation. There were no hematologic or biochemical abnormalities. Although there is the possibility that PDA may have closed spontaneously, it is proposed that paracetamol could contribute to the closure of PDA in preterm infants.
Oral medications regarding their safety and efficacy in the management of patent ductus arteriosus
Oncel, Mehmet Yekta; Erdeve, Omer
2016-01-01
Patent ductus arteriosus (PDA) is a common clinical condition in preterm infants which is inversely related to birth weight and gestational age. Cyclooxygenase inhibitors such as indomethacin and ibuprofen which block the prostaglandin conversion from arachidonic acid are the most commonly used drugs for ductal closure. This review focuses on the safety and efficacy oral medications in the management of PDA in preterm infants. Ibuprofen seems to be the first choice due to its higher safety profile, as it is associated with fewer gastrointestinal and renal side effects when compared to indomethacin. PDA closure rates are better with oral than with intravenous ibuprofen probably due to the pharmacokinetic of the drug. However, these medications were reported to be associated with several adverse including transient renal failure, gastrointestinal bleeding and perforation, hyperbilirubinemia and platelet dysfunction. Paracetamol seems be an alternative to PDA therapy with lower adverse events and side effects. PMID:26862505
Predictors of successful closure of patent ductus arteriosus with indomethacin.
Ahamed, M F; Verma, P; Lee, S; Vega, M; Wang, D; Kim, M; Fuloria, M
2015-09-01
To determine whether platelet counts can predict the likelihood of successful closure of patent ductus arteriosus (PDA) with indomethacin. This was a retrospective cohort study of infants <32 weeks' gestational age (GA) and birth weight <1500 g with PDA. Clinical characteristics between infants who achieved ductal closure with indomethacin and those who failed were compared. Multivariable logistic regression was used to identify predictors of successful ductal closure. In infants with hemodynamically significant PDA, older GA (odds ratio=1.54; 95% confidence interval: 1.12 to 2.13), male gender (odds ratio=3.02; 95% confidence interval: 1.08 to 8.49) and higher platelet count (odds ratio=1.5; 95% confidence interval: 1.04 to 2.17) prior to indomethacin treatment were associated with successful ductal closure with indomethacin. Older GA, male gender and higher platelet count at time of treatment of hemodynamically significant PDA are predictors of successful ductal closure with indomethacin.
Transcatheter closure of a large patent ductus arteriosus using jugular access in an infant.
Fernandes, Precylia; Assaidi, Anass; Baruteau, Alban-Elouen; Fraisse, Alain
2018-03-01
Trans-catheter device closure of patent ductus arteriosus (PDA) via femoral route is the commonly used, safe and effective procedure. Trans-jugular approach has been successfully used in older children with interrupted inferior vena cava. We report a case of successful occlusion of PDA using Amplatzer duct occluder (ADO) via trans-jugular approach following difficulties encountered in gaining femoral venous access. A 6-month-old male infant, weighing 8 kg was admitted for percutaneous catheter closure of PDA. Echocardiogram showed a 4.5 mm duct and left heart dilatation. Femoral venous access was not possible; therefore, we decided to use a trans-jugular approach. The duct was occluded using 8/6 mm ADO. Successful closure of the duct was confirmed with an aortogram. Post procedure echocardiogram showed no residual shunt across the duct. We highlight that trans-catheter closure of PDA using jugular venous access is safe and effective even in infants.
Phenolic Composition, Antioxidant Capacity and in vitro Cytotoxicity Assessment of Fruit Wines
Ljevar, Ana; Tomašević, Marina; Radošević, Kristina; Srček, Višnja Gaurina; Ganić, Karin Kovačević
2016-01-01
Summary Fruit wines contain a wide range of phenolic compounds with biological effects, but their composition and potential benefits to human health have been studied to the much lesser extent compared to grape wines. The aim of this research is to study the phenolic profile of different types of fruit wines and to evaluate their antioxidant and biological potential. Commercially available fruit wines from blackberry, cherry, raspberry, blackcurrant, strawberry and apple produced in Croatia were analyzed. To the best of our knowledge, this study represents the first comprehensive screening of Croatian fruit wines. The phenolic characterization was performed by spectrophotometry and HPLC-PDA/MS analysis. The antioxidant capacity was determined using ABTS and FRAP assays, while in vitro biological activity was analyzed by the cytotoxicity assay on human breast (MCF-7), colon (CaCo-2) and cervical (HeLa) cancer cell lines. Among the studied fruit wines, blackberry, cherry and blackcurrant wines contained the highest amount of total phenolics, while the last two also contained the highest amount of total anthocyanins. The analysis of individual phenolic compounds showed distinctive phenolic composition of each type of fruit wine, notably as regards anthocyanins. Blackberry, followed by cherry, raspberry and blackcurrant wines also had a significantly higher antioxidant capacity than strawberry and apple wines. Fruit wines inhibited the growth of human cancer cells in vitro in a dose--dependent manner with differing susceptibility among tested cancer cells. Blackberry, cherry, raspberry and blackcurrant wines in the volume ratio of 10 and 20% showed to be the most effective anti-proliferative agents, with higher susceptibility in HeLa and MCF-7 cells than CaCo-2 cells. PMID:27904404
Sallmon, Hannes; Weber, Sven C; Dirks, Juliane; Schiffer, Tamara; Klippstein, Tamara; Stein, Anja; Felderhoff-Müser, Ursula; Metze, Boris; Hansmann, Georg; Bührer, Christoph; Cremer, Malte; Koehne, Petra
2018-01-01
The role of platelets for mediating closure of the ductus arteriosus in human preterm infants is controversial. Especially, the effect of low platelet counts on pharmacological treatment failure is still unclear. In this retrospective study of 471 preterm infants [<1,500 g birth weight (BW)], who were treated for a patent ductus arteriosus (PDA) with indomethacin or ibuprofen, we investigated whether platelet counts before or during pharmacological treatment had an impact on the successful closure of a hemodynamically significant PDA. The effects of other factors, such as sepsis, preeclampsia, gestational age, BW, and gender, were also evaluated. Platelet counts before initiation of pharmacological PDA treatment did not differ between infants with later treatment success or failure. However, we found significant associations between low platelet counts during pharmacological PDA therapy and treatment failure ( p < 0.05). Receiver operating characteristic (ROC) curve analysis showed that platelet counts after the first, and before and after the second cyclooxygenase inhibitor (COXI) cycle were significantly associated with treatment failure (area under the curve of >0.6). However, ROC curve analysis did not reveal a specific platelet cutoff-value that could predict PDA treatment failure. Multivariate logistic regression analysis showed that lower platelet counts, a lower BW, and preeclampsia were independently associated with COXI treatment failure. We provide further evidence for an association between low platelet counts during pharmacological therapy for symptomatic PDA and treatment failure, while platelet counts before initiation of therapy did not affect treatment outcome.
Hekim Yılmaz, Emine; Bulut, Mustafa Orhan; Küçük, Mehmet; Yücel, İlker Kemal; Erdem, Abdullah; Çelebi, Ahmet
2018-03-21
To report clinical and procedural characteristics of twelve patients who received a covered stent for the treatment of aortic coarctation and concurrent patent ductus arteriosus (PDA). A single center database was retrospectively evaluated to obtain data of patients with combined aortic coarctation and PDA. We selected patients in whom a covered stent was used for the treatment of both pathologies. The stent length was chosen so as to cover the entire length of the lesion from healthy to healthy tissue and also cover the ampulla of PDA. The median age of the patients was 15 (range, 6.5-35) years. The diameter of the coarctated segment increased from a median of 8.4 (range, 2.6-10.8) mm to 16 (range, 9-24) mm (p<0.005), whereas the pressure gradient decreased from a median of 43 (range, 10-71) mm Hg to 0 (range, 0-8) mm Hg (p<0.005). Fourteen covered stents were used for 12 patients. Following deployment, seven stents were flared with larger and low-pressure balloons because of the gap between the distal end of the stent and the poststenotic dilated segment of the aorta, which caused residual PDA shunts and/or instability of the stent. After the procedure, no residual PDA shunt was present in any patient. To the best of our knowledge, this study includes the largest series of patients reported in literature in whom covered CP stents were used for simultaneous percutaneous treatment of coarctation and PDA. The procedure was successful and stable results were obtained during follow-up in all cases.
A dynamic family planning and health campaign.
1986-11-01
Any successful development program that combines family planning, nutrition, and parasite control such as the integrated project, must include effective information, education, and communication (IEC) components. The Population an Community Development Association (PDA), the largest nonprofit organization in Thailand provides a network of family planning service delivery composed of volunteer distributors including midwives, school techers and shopkeepers. Reliability and accessibility are the 2 important elements. A concerted media campaign which exposes people to condoms and other contraceptives helps desensitize an otherwise "too personal" issue. The problem which confronts family planning communication is how to counteract the sensuous messages form advetisers while focusing on mundane topics such as maternal and child health, responsible parenthood, and family budgets. The PDA has tried to use the same attractions to promote family planning. It distributes promotional items such as T-shirts, pens towels and cigarette lighters bearing family planning messages. In addition to the use of television and radio, PDA also utilizes every possible channel of communication. Approaches include: the Youth-to-Youth Program; informational exhibits; video-mobile vans which visit schools and factories; and the holding of PDA's vasectomy festivals. Informational exhibits on family planning and health care use a variety of audio-visual methods. Video is an effective communication medium. The PDA video material ordinarily consists of family dramas illustrating good and bad family planning practices. By holding vasectomy festivals, PDA provides a media-attracting forum to educate the public and promote vasectomey as the most effective birth control method. Mass media campaigns must be linked with fieldwork outreach.
de Jesus, Christopher; Stacey, Dawn; Dervin, Geoffrey F
2017-11-01
Many patients with isolated medial compartment osteoarthritis are candidates for either unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA). A novel patient decision aid (PDA) was developed to educate patients on both interventions and prepare them for making the decision with their surgeon. The study objective was to evaluate the acceptability and usefulness of a PDA for informing and helping patients reach a surgical preference without increasing decisional conflict. A PDA was developed in accordance with the criteria listed by Ottawa Decision Support Framework and prospectively tested in UKA and TKA patients, who were mailed the PDAs to complete at home along with outcome measures before surgeon consultation. Of 50 patients who consented to participate, 45 patients (26 men, 19 women) used the PDA. Quantitative analysis of acceptability, decisional conflict, knowledge, and preferred surgical option was then performed. Mean patient age was 64.6 years (range, 50-80 years). Patients rated the PDA as acceptable: 84.4% indicated balanced presentation of information and 77.8% asserted that PDA helped them to make decisions between UKA and TKA. Mean knowledge score was 86.6% and total decisional conflict was 19.7 out of 100. Of 45, 33 stated a preferred option (24 UKA; 9 TKA; 12 unsure). Patients understood the majority of the benefits and risks for each surgical option without increasing decisional conflict. The decision aid for advanced medial compartment osteoarthritis is shown to be acceptable and useful for choosing between UKA and TKA. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Xiaoli; Lu, Haijun; Zhang, Yun; He, Fu; Jing, Lingyun; He, Xinghua
2016-12-01
A simple and efficient method for production of magnetic composites by decorating CoFe2O4 with polydopamine (PDA) through oxidative polymerization of dopamine was conducted. Further, magnetic alginate beads with porous structure containing well-dispersed CoFe2O4-PDA were fabricated by ionic crosslinking technology. The resulting SA@CoFe2O4-PDA beads were characterized using scanning electron microscopy, Fourier transform infrared spectrometry, X-ray diffractometer, vibrating sample magnetometer and X-ray photoelectron spectroscopy. Adsorption potential of SA@CoFe2O4-PDA beads for organic dyes including Methylene Blue (MB), Crystal Violet (CV) and Malachite Green (MG) was evaluated. SA@CoFe2O4-PDA beads exhibited excellent adsorption performances due to the composite effect, large surface area and porous structure. Organic dyes could be removed from water solution with high efficiency in a wide pH range of 4.0-9.0. Moreover, it exhibited much higher adsorptivity towards MB and CV with the maximum adsorption capacities of 466.60 and 456.52 mg/g, respectively, which were much higher than that of MG (248.78 mg/g). Ca-electrolyte had obvious adverse effects on MB and CV adsorption than MG. FTIR and XPS demonstrated that carboxylate, catechol, hydroxyl and amine groups might be involved in adsorption of organic dyes. The characteristics of wide pH range, high adsorption capacity and convenient magnetic separation would make SA@CoFe2O4-PDA beads as effective adsorbent for removal of organic dyes from wastewater.
NASA Astrophysics Data System (ADS)
Rai, Akhand; Upadhyay, S. H.
2017-09-01
Bearing is the most critical component in rotating machinery since it is more susceptible to failure. The monitoring of degradation in bearings becomes of great concern for averting the sudden machinery breakdown. In this study, a novel method for bearing performance degradation assessment (PDA) based on an amalgamation of empirical mode decomposition (EMD) and k-medoids clustering is encouraged. The fault features are extracted from the bearing signals using the EMD process. The extracted features are then subjected to k-medoids based clustering for obtaining the normal state and failure state cluster centres. A confidence value (CV) curve based on dissimilarity of the test data object to the normal state is obtained and employed as the degradation indicator for assessing the health of bearings. The proposed outlook is applied on the vibration signals collected in run-to-failure tests of bearings to assess its effectiveness in bearing PDA. To validate the superiority of the suggested approach, it is compared with commonly used time-domain features RMS and kurtosis, well-known fault diagnosis method envelope analysis (EA) and existing PDA classifiers i.e. self-organizing maps (SOM) and Fuzzy c-means (FCM). The results demonstrate that the recommended method outperforms the time-domain features, SOM and FCM based PDA in detecting the early stage degradation more precisely. Moreover, EA can be used as an accompanying method to confirm the early stage defect detected by the proposed bearing PDA approach. The study shows the potential application of k-medoids clustering as an effective tool for PDA of bearings.
Gulack, Brian C.; Laughon, Matthew M.; Clark, Reese H.; Sankar, Meera N.; Hornik, Christoph P.; Smith, P. Brian
2015-01-01
Background Patent ductus arteriosus (PDA) is common in extremely premature infants and associated with increased morbidity and mortality. Medical management of PDA uses either indomethacin or ibuprofen. Despite numerous studies, uncertainty exists as to which drug is safer or more effective; we sought to fill this knowledge gap. Methods We identified infants <28 weeks gestational age discharged from neonatal intensive care units included in the Pediatrix Medical Group Clinical Data Warehouse between 2006 and 2012 who were treated with indomethacin or ibuprofen between postnatal day 2 and 14. Infants treated with both drugs or infants with a congenital malformation were excluded. We used multivariable logistic regression to determine the association of indomethacin versus ibuprofen on clinical outcomes. Results Of 6349 patients who met study criteria, 1177 (19%) received ibuprofen and 5172 (81%) received indomethacin. The median gestational age was 25 weeks (interquartile range 24–26), and 2894 (46%) infants were <750 g at birth. On unadjusted analysis, infants who received ibuprofen had significantly higher incidences of death prior to discharge, surgical ligation of the PDA prior to discharge, death or spontaneous intestinal perforation within 7 days of therapy, death or surgical ligation of the PDA prior to discharge, and an elevated creatinine within 7 days of treatment. However, on multivariable analysis, no significant differences in outcomes were observed (odds ratio for death/PDA ligation for ibuprofen vs. indomethacin = 1.12 [95% CI 0.91–1.39]). Conclusions We observed similar effectiveness and safety profiles for indomethacin and ibuprofen in the medical management of PDA in premature infants. PMID:26386610
Yi, Mi; Sun, Hongyang; Zhang, Hongcheng; Deng, Xuliang; Cai, Qing; Yang, Xiaoping
2016-01-01
To obtain a kind of light-curable fiber-reinforced composite for dental restoration, an excellent interfacial adhesion between the fiber and the acrylate resin matrix is quite essential. Herein, surface modification on glass fibers were carried out by coating them with poly(methyl methacrylate) (PMMA), polydopamine (PDA), or both. The PMMA or PDA coating was performed by soaking fibers in PMMA/acetone solution or dopamine aqueous solution. PDA/PMMA co-coated glass fibers were obtained by further soaking PDA-coated fibers in PMMA/acetone solution. These modified fibers were impregnated with bisphenol A glycidyl methacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) (5:5, w/w) dental resin at a volume fraction of 75%, using unmodified fibers as reference. Light-cured specimens were submitted to evaluations including flexural properties, morphological observation, dynamic mechanical thermal analysis (DMTA) and pull-out test. In comparison with unmodified glass fibers, all the modified glass fibers showed enhancements in flexural strength and modulus of Bis-GMA/TEGDMA resin composites. Results of DMTA and pull-out tests confirmed that surface modification had significantly improved the interfacial adhesion between the glass fiber and the resin matrix. Particularly, the PDA/PMMA co-coated glass fibers displayed the most efficient reinforcement and the strongest interfacial adhesion due to the synergetic effects of PDA and PMMA. It indicated that co-coating method was a promising approach in modifying the interfacial compatibility between inorganic glass fiber and organic resin matrix. Copyright © 2015 Elsevier B.V. All rights reserved.
Ali, Safaa; El Sisi, Amel
2015-01-01
Aim To assess the challenges, feasibility, and efficacy of device closure of patent ductus arteriosus (PDA) in small children weighing ⩽10 kg for different types of devices used in an initial experience at Sohag University hospital. Methods Between March 2011 and September 2014, 91 patients with PDA underwent transcatheter closure in our institute, among whom 54 weighed ⩽10 kg. All of these patients underwent transcatheter closure of PDA using either a Cook Detachable Coil, PFM Nit-Occlud, or Amplatzer duct occluder. A retrospective review of the treatment results and adverse events was performed. Results Successful device placement was achieved in 53/54 small children (98.1%). The median minimum PDA diameter was 2.4 mm [interquartile range (IQR, 1.8–3.5 mm), median weight 8 kg (IQR, 7–10 kg), and median age 10 months (IQR, 8–17 months)]. Mild aortic obstruction occurred in one case (1.9%), as the device became displaced towards the aorta after release. The device embolized in one case (1.9%) and no retrieval attempt was made. Five cases (9.3%) had minor vascular complications. Conclusion With the current availability of devices for PDA closure, transcatheter closure of PDA is considered safe and efficacious in small children weighing ⩽10 kg with good mid-term outcome. The procedure had a low rate of high-severity adverse events even with the initial experience of the catheterization laboratory. PMID:27053899
Vijayalakshmi, Ishwarappa Balekundri; Setty, Natraj; Narasimhan, Chitra; Singla, Vivek; Manjunath, Cholenahalli Nanjappa
2014-12-01
Device closure of patent ductus arteriosus (PDA) is treatment of choice. But device closure in presence of pulmonary artery hypertension (PAH) remains a challenge. Data on patient selection, technical considerations, and complications are limited. To know the challenges and efficacy of device closure of PDA with PAH. Out of 1,325 cases of device closure of PDA, 246 (18.6%) with PAH formed the study material. To test the feasibility, chosen device is used to occlude PDA for ten minutes without oxygen inhalation. The device is released only if PAH reduced. PAH decreased in all except in 1 patient after closure with muscular ventricular septal occluder (MVSDO), pulmonary artery pressure (PAP) transiently increased (became supra-systemic), without significant reduction in aortic pressure. Device embolized in 8 patients (3.3%). Percutaneous retrieval was done in 4 (by snare in 2 and by fixing the cable to device in 2) and replaced with bigger devices. The surgical removal of the embolized MVSDO and ligation was done in 4 cases. All patients were on oral sildenafil and bosentan until PAP regressed to normal. Follow up was from 6 months to 9 years. No residual shunt in any patient on follow-up. The PAP regressed to normal in all except 5 cases (2.03%) of Down's syndrome with systemic PAP. Device closure of PDA with PAH is feasible, safe in all age groups. Temporary PDA occlusion with device is effective and time saving for evaluating pulmonary vascular reactivity. Device embolization in aorta is higher with severe PAH. Novel method of retrieval is effective. © 2014, Wiley Periodicals, Inc.
Chang, Szu-Ling; Lin, Wen-Li; Weng, Chien-Hsiang; Wu, Shye-Jao; Tsai, Hsin-Jung; Wang, Shwu-Meei; Peng, Chun-Chih; Chang, Jui-Hsing
2018-04-01
Patent ductus arteriosus (PDA) is one of the most common cardiac conditions in preterm infants. Closure of the PDA in symptomatic patients can be achieved medically or surgically. Atropine is commonly administered in general anesthesia as a premedication in this age group but with limited evidence addressing the effect of its use. Our study examined the association of the use of atropine as a premedication in PDA ligation and the risk of post-operative respiratory complications. This retrospective cohort study included 150 newborns who have failed medical treatment for PDA and received PDA ligation during 2008-2012 in a single tertiary medical center. Ninety-two of them (61.3%) received atropine as premedication for general anesthesia while 58 (38.7%) did not. Post-operative respiratory condition, the need of cardiopulmonary resuscitation and the presence of bradycardia were measured. Patients with atropine use were associated with increased odds of respiratory acidosis in both univariate analysis (22.9% vs 7.3%; OR = 3.785, 95% CI = 1.211-11.826, p = 0.022) and multivariate analysis (OR = 4.030, 95% CI = 1.230-13.202, p = 0.021), with an even higher odds of respiratory acidosis in patients receiving both atropine and ketamine. The use of atropine as premedication in general anesthesia for neonatal PDA ligation is associated with higher risk of respiratory acidosis, which worsens with the combined use of ketamine. Copyright © 2017. Published by Elsevier B.V.
Norman, Geoffrey; Keane, David; Oppenheimer, Lawrence
2008-01-01
For several years, final-year students at McMaster University have been required to complete 10 mini-CEX type assessments per rotation. A similar system was being introduced at Ottawa. To facilitate data capture, we decided to introduce a personal data assistant (PDA)-based system and evaluate its impact. A randomized trial was designed to compare the acceptability of PDA and printed evaluation forms. The trial failed because of clerks' unwillingness to use PDAs. A focus group was held and user surveys were administered, chiefly by e-mail, to explore students' preference for printed forms. Thirty percent of invited clerks (52/176) agreed to use a PDA; 6% (11; 21% of those agreeing) recorded one or more encounters; 2% (4) recorded at least the minimum number of evaluations required by their program. Most survey respondents expressed concerns related primarily to the relative inconvenience of PDAs compared to paper, a judgment reflecting the time required both to install required software and to become familiar with the software and data entry form, and to record information via the form. A minority were also concerned about assessors' willingness or ability to use PDA forms. Before asking students and clinical supervisors to use a PDA-based encounter-evaluation form in clerkship, planners should conduct a careful assessment of the advantages and disadvantages for students of the system they hope to implement. The prima facie greater convenience and efficiency of the PDA may actually be offset by workplace disincentives and inefficiencies in data recording, relative to the incentives and efficiencies associated with a system based on printed (paper) forms.
Impact of stressful life events on the course of panic disorder in adults.
Moitra, Ethan; Dyck, Ingrid; Beard, Courtney; Bjornsson, Andri S; Sibrava, Nicholas J; Weisberg, Risa B; Keller, Martin B
2011-11-01
Panic disorder with/without agoraphobia (PD/PDA) is a prevalent anxiety disorder, associated with impairment in quality of life and functionality, as well as increased healthcare utilization. Extant research shows a relationship between stressful life events (SLEs) and the onset of panic attacks in adults who ultimately develop PD/PDA. However, limited attention has been paid to how SLEs might affect the severity of panic symptoms in individuals with PD/PDA. In this study, we examined the relationship between SLEs and panic symptom severity in adults with PD/PDA. Four hundred-eighteen adults with PD/PDA from the Harvard/Brown Anxiety Research Program (HARP), a long-term prospective longitudinal observational multicenter study of adults with a current or past history of anxiety disorders were included in this study. We examined occurrence of SLEs and their impact on panic symptom severity 12-weeks pre- and post-SLE. A time-slope effect showed that participants had worsened panic symptoms over the course of the 12-weeks after family/friends/household and work SLEs. That is, their symptoms worsened progressively after the event, rather than immediately thereafter (i.e., significant symptom change within the same week of the event). The sample may not be representative of the general population. These findings provide new insights into how SLEs affect panic symptoms in adults with PD/PDA in that household-related SLEs, such as serious family arguments, and work-related SLEs, such as being fired, put some adults at risk for worsened panic symptoms within 12-weeks of the event. Copyright © 2011 Elsevier B.V. All rights reserved.
El-Mashad, Abd El-Rahman; El-Mahdy, Heba; El Amrousy, Doaa; Elgendy, Marwa
2017-02-01
In this prospective study, we compared the efficacy and side effects of indomethacin, ibuprofen, and paracetamol in patent ductus arteriosus (PDA) closure in preterm neonates. Three hundred preterm neonates with hemodynamically significant PDA (hs-PDA) admitted at our neonatal intensive care unit were enrolled in the study. They were randomized into three groups. Group I (paracetamol group) received 15 mg/kg/6 h IV paracetamol infusion for 3 days. Group II (ibuprofen group) received 10 mg/kg IV ibuprofen infusion followed by 5 mg/kg/day for 2 days. Group III (indomethacin group) received 0.2 mg/kg/12 h indomethacin IV infusion for three doses. Laboratory investigations such as renal function test, liver function test, complete blood count, and blood gases were conducted in addition to echocardiographic examinations. All investigations were done before and 3 days after treatment. There was no significant difference between all groups regarding efficacy of PDA closure (P = 0.868). There was a significant increase in serum creatinine levels and serum blood urea nitrogen (BUN) in the ibuprofen and indomethacin groups (P < 0.001). There was a significant reduction in platelet count and urine output (UOP) in both ibuprofen and indomethacin groups (P < 0.001). There was a significant increase in bilirubin levels in only the ibuprofen group (P = 0.003). No significant difference of hemoglobin (HB) level or liver enzymes in all groups (P > 0.05). Ventilatory settings improved significantly in patients with successful closure of PDA than those with failed PDA closure (P < 0.001). Paracetamol is as effective as indomethacin and ibuprofen in closure of PDA in preterm neonates and has less side effects mainly on renal function, platelet count, and GIT bleeding. What is Known: • Hemodynamically significant patent ductus arteriosus has many complications for preterm and low birth weight neonates and better to be closed. Many drugs were used for medical closure of PDA e.g. indomethacin, ibuprofen and recently paracetamol. Many studies compare safety and efficacy of paracetamol with either indomethacin or ibuprofen. What is New: • It is the first large study that compares the efficacy and side effects of the three drugs in one study.
NASA Astrophysics Data System (ADS)
Jin, Shicun; Li, Kuang; Li, Jianzhang
2018-07-01
Biopolymers show a broad prospect as an effective alternative to petroleum-based materials. However, assembling biopolymers into the composites with integrated high strength and toughness still remains a great challenge. Herein, we developed a novel and versatile mussel-inspired modification design for tough and high-performance graphene oxide (GO)/soy protein isolate (SPI) nanocomposite films, where the GO nanosheets were modified with poly(dopamine) (PDA) to improve the dispersion of GO nanosheets in SPI matrix and enhance their interfacial adhesion. As expected, at 0.6 wt% of PDA-modified GO (PDG) loading, the tensile strength and toughness of the SPI/PDG films reached 8.87 MPa and 22.82 MJ m-3, respectively, which simultaneously showed 86.34% and 263.95% higher than those of pristine film. The great enhancement of mechanical behaviors was due to the increased fracture line energy and the lack of significant coalescence of microcracks, as well as the strong interfacial adhesion force between peptide chains and PDG nanosheets. The resultant nanocomposite films also exhibited favorable vapor barrier behavior and water-resistance. The proposed method in this paper opens a new avenue for assembling two-dimensional nanosheets into the biopolymer-based composites with integrated high strength and great toughness for a series of innovative future applications.
PDA: Paradigm-Disrupting Appliance?
ERIC Educational Resources Information Center
Cain, Mark
2003-01-01
Discusses personal digital assistants (PDAs). Highlights include history and characteristics of PDAs; beyond the "organizer" function and use of PDAs in higher education and academic libraries; problems and possibilities of a wirelessly networked PDA in a library; and the future outlook for PDAs. (AEF)
NASA Astrophysics Data System (ADS)
Zheng, Y.; Lu, S. X.; Xu, W. G.; He, G.; Cheng, Y. Y.; Xiao, F. Y.; Zhang, Y.
2018-01-01
In this work, a composite electrode was fabricated by chemical deposition of polydopamine (PDA) and graphene oxide (GO) on the copper foam (CF) surface, followed by annealing treatment. Owing to the cohesive effect of the PDA middle film, GO was coated on CF surface successfully, and then reduced simultaneously while annealing. The resulted rGO/PDA/CF composite electrode was directly used as a supercapacitor electrode and exhibited excellent electrochemical performance, with a high specific capacitance of 1250 F g-1 at 2 A g-1 and favorable cycle stability.
Echocardiography for patent ductus arteriosus including closure in adults.
Chugh, Reema; Salem, Morris M
2015-01-01
Patent ductus arteriosus (PDA) represents at least 5-10% of all congenital heart defects (CHDs) making it a very important commonly diagnosed lesion. Although spontaneous closure of the PDA occurs within 24 to 48 hours after birth in the majority, those children who do not have natural or surgical closure may have a persistent PDA into adulthood. The diagnosis is most often confirmed by echocardiography that also guides catheter-based interventions and surgeries. Echocardiography continues to be the most important tool in long-term follow-up of residua and sequelae. © 2014, Wiley Periodicals, Inc.
Patent ductus arteriosus in a lamb: A case report
Jafari Dehkordi, Afshin; Hoseini, Farzaneh
2016-01-01
Patent ductus arteriosus (PDA) is a persistent patency of a vessel normally present in the fetus that connects the pulmonary arterial system to the aorta. The ductus arteriosus fails to close at birth when breathing commences and placental blood circulation is removed. Closure of the ductus arteriosus arises in response to decline pulmonary vascular resistance and increased systemic vascular resistance. This report describes a case of PDA in a two-month-old male lamb with clinical signs of machinery murmur, tachycardia, increase respiratory rate, weakness and ill thrift. Echocardiographic examination and necropsy finding confirmed PDA. PMID:27226893
Gentry, Tony; Kriner, Richard; Sima, Adam; McDonough, Jennifer; Wehman, Paul
2015-03-01
Personal digital assistants (PDAs) are versatile task organizers that hold promise as assistive technologies for people with cognitive-behavioral challenges. This delayed randomized controlled trial compared two groups of adult workers with autism spectrum disorder (ASD) to determine whether the use of an Apple iPod Touch PDA as a vocational support improves work performance and reduces personal support needs on the job. Baseline data were collected on 50 adults with ASD who were beginning a vocational placement supported by a job coach. Participants were randomized to receive training in the use of a PDA as a vocational aid upon starting their job or after working 12 weeks without PDA support. Workers who received PDA training at the beginning of their job placement required significantly less hours of job coaching support (p = 0.013) during their first 12 weeks on the job than those who had not yet received the intervention. Functional performance between the two groups was not significantly different. The significant difference in hours of job coaching support persisted during the subsequent 12 weeks, in which both groups used a PDA (p = 0.017).
Wang, Rong; Neoh, Koon Gee; Kang, En-Tang; Tambyah, Paul Anantharajah; Chiong, Edmund
2015-04-01
Urinary tract infections constitute a large proportion of nosocomial infections, and the urinary catheter is the most important predisposing factor. Encrustation induced by urease-producing uropathogens like Proteus mirabilis causes further complications. In the present work, a strategy for controllable and sustained release of silver over several weeks has been developed for combating bacterial infection and encrustation in urinary devices. Silver nanoparticles (AgNPs) were first immobilized on polydopamine (PDA) pre-treated silicone catheter surface and this was followed by another PDA coating. The number of AgNP-PDA bilayers could be manipulated to control the amount of silver loaded and its subsequent release. Poly(sulfobetaine methacrylate-co-acrylamide) was then grafted to provide an antifouling outer layer, and to ensure free diffusion of Ag from the surface. The micron-scale combination of an antifouling coating with AgNP-PDA bilayers reduced colonization of the urinary catheter by uropathogens by approximately two orders of magnitude. With one and two AgNP-PDA bilayers, the coated catheter could resist encrustation for 12 and 45 days, respectively, compared with approximately 6 days with the Dover™ silver-coated catheter. Such anti-infective and anti-encrustation catheters can potentially have a large impact on reducing patient morbidity and healthcare expenditure. © 2014 Wiley Periodicals, Inc.
Acetaminophen for patent ductus arteriosus.
Le, Jennifer; Gales, Mark A; Gales, Barry J
2015-02-01
To evaluate the literature describing acetaminophen use in treatment of patent ductus arteriosus (PDA). Searches were conducted in MEDLINE with full text (EBSCOhost; 1946 to September 2014) using the search terms acetaminophen, paracetamol, and patent ductus arteriosus. The references of identified articles were reviewed to identify other relevant articles. Human clinical trials and case reports limited to the English language were reviewed. In all, 12 case reports and 2 randomized, controlled clinical trials explored the use of acetaminophen in treating PDA. The case reports described the use of oral or intravenous acetaminophen in patients with contraindications to or who had previously failed nonsteroidal anti-inflammatory drug therapy for PDA. More than 76% of patients achieved successful PDA closure in reported cases. The clinical trials compared the efficacy of oral acetaminophen versus oral ibuprofen in preterm infants. Acetaminophen was noninferior to ibuprofen, with closure rates from 72.5% to 81.2%. The acetaminophen dose used in most case series and trials was 15 mg/kg dose every 6 hours for 3 days. Acetaminophen therapy was well tolerated, with only a few incidents of elevated liver enzymes being reported. Oral acetaminophen is an alternative to PDA therapy in preterm infants when indomethacin/ibuprofen is not effective or is contraindicated, and it may be considered before surgical ligation. © The Author(s) 2014.
Jung, Sung-Ho; Jang, Huisoo; Lim, Min-Cheol; Kim, Jae-Hwan; Shin, Kong-Sik; Kim, Sun Min; Kim, Hae-Yeong; Kim, Young-Rok; Jeon, Tae-Joon
2015-02-17
We developed a simple and sensitive colorimetric biosensor in the form of microparticles by using polydiacetylene (PDA) vesicles encapsulated within a hydrogel matrix for the detection of phosphinothricin acetyltransferase (PAT) protein, which is one of the most important marker proteins in genetically modified (GM) crops. Although PDA is commonly used as a sensing material due to its unique colorimetric properties, existing PDA biosensors are ineffective due to their low sensitivity as well as their lack of robustness. To overcome these disadvantages, we devised immunohydrogel beads made of anti-PAT-conjugated PDA vesicles embedded at high density within a poly(ethylene glycol) diacrylate (PEG-DA) hydrogel matrix. In addition, the construction of immunohydrogel beads was automated by use of a microfluidic device. In the immunoreaction, the sensitivity of antibody-conjugated PDA vesicles was significantly amplified, as monitored by the unaided eye. The limit of detection for target molecules reached as low as 20 nM, which is sufficiently low enough to detect target materials in GM organisms. Collectively, the results show that immunohydrogel beads constitute a promising colorimetric sensing platform for onsite testing in a number of fields, such as the food and medical industries, as well as warfare situations.
Garrett, Bernard Mark; Jackson, Cathryn
2006-12-01
This paper outlines the development and evaluation of a wireless personal digital assistant (PDA) based clinical learning tool designed to promote professional reflection for health professionals. The "Clinical e-portfolio" was developed at the University of British Columbia School of Nursing to enable students immediately to access clinical expertise and resources remotely, and record their clinical experiences in a variety of media (text, audio and images). The PDA e-portfolio tool was developed to demonstrate the potential use of mobile networked technologies to support and improve clinical learning; promote reflective learning in practice; engage students in the process of knowledge translation; help contextualize and embed clinical knowledge whilst in the workplace; and to help prevent the isolation of students whilst engaged in supervised clinical practice. The mobile e-portfolio was developed to synchronise wirelessly with a user's personal Web based portfolio from any remote location where a cellular telephone signal or wireless (Wi-Fi) connection could be obtained. An evaluation of the tool was undertaken with nurse practitioner and medical students, revealing positive attitudes to the use of PDA based tools and portfolios, but limits to the use of the PDA portfolio due to the inherent interface restrictions of the PDA.
Utilization of personal digital assistants (PDAS) by pediatric and emergency medicine residents.
Khan, Abu N G A; Frank, Joshua; Geria, Rajesh; Davidson, Steven
2007-05-01
The objective of the present study was to investigate the current personal digital assistant (PDA) usage patterns of the residents and their interest in future PDA-based applications. A cross-sectional survey was conducted among the Pediatrics (Peds) and Emergency Medicine (EM) residents in an urban teaching hospital. Data points included level of training, specialty of training, experience of use of different PDA devices, use of current software applications, and interest in future applications. A total of 60/74 (81%) eligible residents participated in the study. Palm (Palm Inc., Sunnyvale, CA) was the most commonly used operating system (82%). Among the PDA users, 82% reported using the device several times a day, and 16% used them a few times a week. The most commonly used applications included the simple calculator (81%), drug references (80%), medical calculators (75%), electronic textbooks (66%), and schedule and contact information (42%). In addition, residents showed interest in using PDA applications for procedure logs, patient tracking, and prescription writing. No significant differences were noted in the frequency and expertise of using PDAs between the Peds and EM residents (p = 0.29). Our data show current trends of use of PDAs by Peds and EM residents and their interest for future applications.
Patent Ductus Arteriosus in Premature Neonates
Mezu-Ndubuisi, Olachi J.; Agarwal, Ghanshyam; Raghavan, Aarti; Pham, Jennifer T.; Ohler, Kirsten H.; Maheshwari, Akhil
2015-01-01
Persistent patency of the ductus arteriosus is a major cause of morbidity and mortality in premature infants. In infants born prior to 28 weeks of gestation, a hemodynamically-significant patent ductus arteriosus (PDA) can cause cardiovascular instability, exacerbate respiratory distress syndrome, prolong the need for assisted ventilation, and increase the risk of bronchopulmonary dysplasia, intraventricular hemorrhage, renal dysfunction, intraventricular hemorrhage, cerebral palsy, and mortality. In this article, we review the pathophysiology, clinical features, and assessment of hemodynamic significance, and provide a rigorous appraisal of the quality of evidence to support current medical and surgical management of PDA of prematurity. Cyclo-oxygenase inhibitors such as indomethacin and ibuprofen remain the mainstay of medical therapy for PDA, and can be used both for prophylaxis as well as rescue therapy to achieve PDA closure. Surgical ligation is also effective and is used in infants who do not respond to medical management. Although both medical and surgical treatment have proven efficacy in closing the ductus, both modalities are associated with significant adverse effects. Because the ductus does undergo spontaneous closure in some premature infants, improved and early identification of infants most likely to develop a symptomatic PDA could help in directing treatment to the at-risk infants and allow others to receive expectant management. PMID:22564132
El-Khuffash, Afif; Jain, Amish; Corcoran, David; Shah, Prakesh S; Hooper, Christopher W; Brown, Naoko; Poole, Stanley D; Shelton, Elaine L; Milne, Ginger L; Reese, Jeff; McNamara, Patrick J
2014-09-01
We evaluated the clinical effectiveness of variable courses of paracetamol on patent ductus arteriosus (PDA) closure and examined its effect on the in vitro term and preterm murine ductus arteriosus (DA). Neonates received one of the following three paracetamol regimens: short course of oral paracetamol (SCOP), long course of oral paracetamol (LCOP), and intravenous paracetamol (IVP) for 2-6 d. Pressure myography was used to examine changes in vasomotor tone of the preterm and term mouse DA in response to paracetamol or indomethacin. Their effect on prostaglandin synthesis by DA explants was measured by mass spectroscopy. Twenty-one preterm infants were included. No changes in PDA hemodynamics were seen in SCOP infants (n = 5). The PDA became less significant and eventually closed in six LCOP infants (n = 7). PDA closure was achieved in eight IVP infants (n = 9). On pressure myograph, paracetamol induced a concentration-dependent constriction of the term mouse DA, up to 30% of baseline (P < 0.01), but required >1 µmol/l. Indomethacin induced greater DA constriction and suppression of prostaglandin synthesis (P < 0.05). The clinical efficacy of paracetamol on PDA closure may depend on the duration of treatment and the mode of administration. Paracetamol is less potent than indomethacin for constriction of the mouse DA in vitro.
Wang, Zhongkai; Chen, Tao; Chen, Liang; Qin, Yongwen; Zhao, Xianxian
2016-01-01
Transcatheter closure is the usual treatment for patent ductus arteriosus (PDA), but its safety and efficacy have not been reported in adult PDA patients with severe mitral regurgitation. A retrospective study on 27 consecutive patients diagnosed with PDA and severe mitral regurgitation and treated using transcatheter closure between September 2010 and September 2012 at the Department of Cardiology of Changhai Hospital in Changhai, China. Left ventricular (LV) diastolic volume and function, pulmonary artery pressure, and instantaneous reverse-flow volume were examined by echocardiography before PDA closure, immediately after closure, and 1 year after closure. After the procedure, the LV diastolic volume (P<.05) and instantaneous reverse-flow volume (P<.001) were significantly decreased. There was no effect on the ejection fraction (P>.05). Pulmonary arterial systolic pressure was unchanged 1 year after closure (from 46.41 ± 19.92 mm Hg to 45.43 ± 13.64 mm Hg; P=.58). All procedures were uneventful and only mild complications occurred (hemolysis in 2 cases, subcutaneous hematoma in 4 cases, and fever in 2 cases). Transcatheter closure can decrease the LV volume and instantaneous reverse-flow volume in adult PDA patients with severe mitral regurgitation. This procedure is effective and has a good safety profile.
Matsumura, Shun; Oshima, Ayumi; Fujinuma, Sumie; Tanaka, Kosuke; Nagano, Nobuhiko; Miyake, Fuyu; Masutani, Satoshi; Tamura, Masanori; Ueda, Keiko; Namba, Fumihiko
2017-10-01
Background Although indomethacin (IND) is the standard treatment for hemodynamically significant patent ductus arteriosus (hsPDA) in Japan, it may be associated with renal impairment and gastrointestinal complications. The use of paracetamol for hsPDA closure has recently increased. Unlike IND, paracetamol does not have a peripheral vasoconstrictive effect and can be given to infants with contraindications to IND. Based on limited data available from randomized trials, paracetamol and IND seem to have similar effects. However, there have been no reports of the use of paracetamol for hsPDA in Japan. Cases Our drug administration protocol was approved by the institutional ethics committee after purchasing a clinical trial insurance. In three premature infants in whom IND was contraindicated or ineffective, a 7.5 mg/kg of paracetamol was intravenously administered every 6 hour for 3 days after obtaining parental consents. A temporary hsPDA closure was observed in two of the three infants. However, all three infants eventually needed surgical closure. No side effects, such as hepatic and renal dysfunctions, and adverse events were reported. Conclusion The intravenous administration of paracetamol was safe and feasible in premature infants with hsPDA. Future clinical trials with optimized dose and timing of administration are needed.
Blaya, J A; Gomez, W; Rodriguez, P; Fraser, H
2008-08-01
One hundred and twenty-six public health centers and laboratories in Lima, Peru, without internet. We have previously shown that a personal digital assistant (PDA) based system reduces data collection delays and errors for tuberculosis (TB) laboratory results when compared to a paper system. To assess the data collection efficiency of each system and the resources required to develop, implement and transfer the PDA-based system to a resource-poor setting. Time-motion study of data collectors using the PDA-based and paper systems. Cost analysis of developing, implementing and transferring the PDA-based system to a local organization and their redeployment of the system. Work hours spent collecting and processing results decreased by 60% (P < 0.001). Users perceived this decrease to be 70% and had no technical problems they failed to fix. The total cost and time to develop and implement the intervention was US$26092 and 22 weeks. The cost to extend the system to cover nine more districts was $1125 and to implement collecting patient weights was $4107. A PDA-based system drastically reduced the effort required to collect TB laboratory results from remote locations. With the framework described, open-source software and local development, organizations in resource-poor settings could reap the benefits of this technology.
ERIC Educational Resources Information Center
Galuszka, Peter
2005-01-01
Using mobile digital devices--iPods, personal digital assistants (PDAs), Tablet PCs or advanced cell phones--is becoming a big campus trend. Their advantages include convenience and the ability to hear lectures or course-related music just about anywhere. PDA's such as Palm Pilots and BlackBerrys, iPods such as Apple's and Tablet PCs, including…
Lindquist, Anna M; Johansson, Pauline E; Petersson, Göran I; Saveman, Britt-Inger; Nilsson, Gunilla C
2008-10-28
Health care personnel need access to updated information anywhere and at any time, and a Personal Digital Assistant (PDA) has the potential to meet these requirements. A PDA is a mobile tool which has been employed widely for various purposes in health care practice, and the level of its use is expected to increase. Loaded with suitable functions and software applications, a PDA might qualify as the tool that personnel and students in health care need. In Sweden today, despite its leadership role in mobile technologies, PDAs are not commonly used, and there is a lack of suitable functions and software applications. The aim of the present review was to obtain an overview of existing research on the use of PDAs among personnel and students in health care. The literature search included original peer-reviewed research articles written in English and published from 1996 to 2008. All study designs were considered for inclusion. We excluded reviews and studies focusing on the use of PDAs in classroom situations. From March 2006 to the last update in May 2008, we searched PubMed, CINAHL, Cochrane, IngentaConnect, and a local search engine (ELIN@Kalmar). We conducted a content analysis, using Nielsen's Model of System Acceptability as a theoretical framework in structuring and presenting the results. From the 900 references initially screened, 172 articles were selected and critically assessed until 48 articles remained. The majority originated in North-America (USA: n=24, Canada: n=11). The categories which emerged from our content analysis coincided to a certain extent to Nielsen's Model of System Acceptability (social and practical acceptability), including usefulness (utility and usability) subcategories such as learnability, efficiency, errors, and satisfaction. The studies showed that health care personnel and students used PDAs in patient care with varied frequency. Most of the users were physicians. There is some evidence that the use of a PDA in health care settings might improve decision-making, reduce the numbers of medical errors, and enhance learning for both students and professionals, but the evidence is not strong, with most studies being descriptive, and only 6 randomized controlled trials. Several special software programs have been created and tested for PDAs, and a wide range of situations for their use have been reported for different patient groups. Drug and medical information were commonly accessed by PDA users, and the PDA was often viewed as the preferred tool when compared to paper-based documents. Some users regarded the PDA easy to operate, while others found it difficult in the beginning. This overview of the use of PDAs revealed a positive attitude towards the PDA, which was regarded as a feasible and convenient tool. The possibility of immediate access to medical information has the potential to improve patient care. The PDA seems to be a valuable tool for personnel and students in health care, but there is a need for further intervention studies, randomized controlled trials, action research, and studies with various health care groups in order to identify its appropriate functions and software applications.
Lindquist, Anna M; Petersson, Göran I; Saveman, Britt-Inger; Nilsson, Gunilla C
2008-01-01
Background Health care personnel need access to updated information anywhere and at any time, and a Personal Digital Assistant (PDA) has the potential to meet these requirements. A PDA is a mobile tool which has been employed widely for various purposes in health care practice, and the level of its use is expected to increase. Loaded with suitable functions and software applications, a PDA might qualify as the tool that personnel and students in health care need. In Sweden today, despite its leadership role in mobile technologies, PDAs are not commonly used, and there is a lack of suitable functions and software applications. Objective The aim of the present review was to obtain an overview of existing research on the use of PDAs among personnel and students in health care. Methods The literature search included original peer-reviewed research articles written in English and published from 1996 to 2008. All study designs were considered for inclusion. We excluded reviews and studies focusing on the use of PDAs in classroom situations. From March 2006 to the last update in May 2008, we searched PubMed, CINAHL, Cochrane, IngentaConnect, and a local search engine (ELIN@Kalmar). We conducted a content analysis, using Nielsen’s Model of System Acceptability as a theoretical framework in structuring and presenting the results. Results From the 900 references initially screened, 172 articles were selected and critically assessed until 48 articles remained. The majority originated in North-America (USA: n=24, Canada: n=11). The categories which emerged from our content analysis coincided to a certain extent to Nielsen’s Model of System Acceptability (social and practical acceptability), including usefulness (utility and usability) subcategories such as learnability, efficiency, errors, and satisfaction. The studies showed that health care personnel and students used PDAs in patient care with varied frequency. Most of the users were physicians. There is some evidence that the use of a PDA in health care settings might improve decision-making, reduce the numbers of medical errors, and enhance learning for both students and professionals, but the evidence is not strong, with most studies being descriptive, and only 6 randomized controlled trials. Several special software programs have been created and tested for PDAs, and a wide range of situations for their use have been reported for different patient groups. Drug and medical information were commonly accessed by PDA users, and the PDA was often viewed as the preferred tool when compared to paper-based documents. Some users regarded the PDA easy to operate, while others found it difficult in the beginning. Conclusions This overview of the use of PDAs revealed a positive attitude towards the PDA, which was regarded as a feasible and convenient tool. The possibility of immediate access to medical information has the potential to improve patient care. The PDA seems to be a valuable tool for personnel and students in health care, but there is a need for further intervention studies, randomized controlled trials, action research, and studies with various health care groups in order to identify its appropriate functions and software applications. PMID:18957381
Stabilization of β-catenin induces pancreas tumor formation
Heiser, Patrick W.; Cano, David A.; Landsman, Limor; Kim, Grace E.; Kench, James G.; Klimstra, David S.; Taketo, Maketo M.; Biankin, Andrew V.; Hebrok, Matthias
2008-01-01
Background & Aims β-catenin signaling within the canonical Wnt pathway is essential for pancreas development. However, the pathway is normally down-regulated in the adult organ. Increased cytoplasmic and nuclear localization of β-catenin can be detected in nearly all human solid pseudopapillary neoplasms (SPN), a rare tumor with low malignant potential. Conversely, pancreatic ductal adenocarcinoma (PDA) accounts for the majority of pancreatic tumors and is one of the leading causes of cancer death. While activating mutations within β-catenin and other members of the canonical Wnt pathway are rare, recent reports have implicated Wnt signaling in the development and progression of human PDA. Here, we sought to address the role of β-catenin signaling in pancreas tumorigenesis. Methods Using Cre/lox technology, we conditionally activated β-catenin in a subset of murine pancreatic cells, in vivo. Results Activation of β-catenin results in the formation of large pancreatic tumors at a high frequency in adult mice. These tumors resemble human SPN based upon morphological and immunohistochemical comparisons. Interestingly, stabilization of β-catenin blocks the formation of pancreatic intraepithlelial neoplasia (PanIN) in the presence of an activating mutation in Kras that is known to predispose individuals to pancreatic ductal adenocarcinoma (PDA). Instead, mice in which β-catenin and Kras are concurrently activated develop distinct ductal neoplasms that do not resemble PanIN lesions. Conclusions These results demonstrate that activation of β-catenin is sufficient to induce pancreas tumorigenesis. Moreover, they indicate that the sequence in which oncogenic mutations are acquired has profound consequences on the phenotype of the resulting tumor. PMID:18725219
Growth and mycotoxin production by Chaetomium globosum.
Fogle, Matthew R; Douglas, David R; Jumper, Cynthia A; Straus, David C
2007-07-01
Chaetomium globosum, the most common species within this genus, produces chaetoglobosins A and C when cultured on building material. Relatively low levels of these compounds have been shown to be lethal to various tissue culture cell lines. This study had two major objectives: (1) to determine the frequency at which Chaetomium species are isolated in water-damaged buildings and (2) to examine the production of chaetoglobosins A and C in isolates of C. globosum obtained from different buildings. Out of 794 water-damaged buildings, Chaetomium species were isolated in 49% of these structures. C. globosum ATCC 16021 was grown on four different media: oatmeal agar (OA), potato dextrose agar (PDA), corn meal agar (CMA), and malt extract agar (MEA). After 4 weeks, fungal growth was evaluated based on colony diameter and the quantity of spores produced on agar plates. In addition, production of chaetoglobosin A and C was monitored using high performance liquid chromatography. Colony diameter, spore production, and mycotoxin production by C. globosum were the highest on OA. Out of 30 C. globosum isolates cultured on OA for 4 weeks, 16 produced detectable amounts of chaetoglobosin A and every isolate produced chaetoglobosin C.
Adusumilli, Sri Raj; Tobin, Jonathan N; Younge, Richard G; Kendall, Mat; Kukafka, Rita; Khan, Sharib; Chang, Otto; Mahabir, Kasandra
2006-01-01
The New York City Department of Health and Mental Hygiene, The Community Health Care Association of New York State and Clinical Directors Network are collaborating on the "eClinician Project," which has distributed seven hundred public health-friendly, wireless (WiFi) enabled Personal Digital Assistants (PDAs) to primary care clinicians working in New York City, federally funded, Community Health Centers (CHC) which serve minority underserved communities that suffer a disproportionate burden of chronic disease and lack access to health promotion disease prevention services. Each participating health center also received a wireless router to create an onsite internet hot spot to enable clinicians to have internet access. The goals of the eClinician Project are to: 1) To encourage adoption of information technology among providers in Community Health Centers in New York City by providing PDAs as a first line strategy towards achieving this goal, 2) enhance access to information on emergency preparedness, 3) improve patient outcomes by providing PDA-based clinical decision-support tools that support evidence-based care, 4) encourage chronic care management and health promotion/disease prevention activities, and 5) increase productivity and efficiency. CHC clinicians have received a hands-on, on-site orientation to PDAs. Ongoing training has continued via online CME-accredited webcasts (see www.CDNetwork.org). Clinical decision-support tools are available for download via the eClinician project web portal (see www.eClinician.org ). Public health alerts can be delivered to the PDAs or to the clinicians' desktop computers. Pre and post training surveys, in addition to a case study, have been used to evaluate the population demographics, PDA adoption by the clinicians, clinician attitudes towards using PDAs, PDA influence on clinical-decision making and barriers to adoption of PDAs and information technology in general.
Butler, D G; Oudit, G Y; Cadinouche, M Z
1995-06-01
Dorsal aortic blood pressure (PSYS, systolic; PDIAS, diastolic; and PDA, mean) and heart rate (HR) were measured in resting freshwater bowfins (n = 6), Amia calva L., before and after i.v. injections of 50, 100, 200, 500, and 1000 ng.kg-1 of synthetic [Asn1, Val5]-angiotensin II (ANG II). Baseline PSYS, PDIAS, and PDA were 27.7 +/- 2.8, 22.4 +/- 1.8, and 24.5 +/- 2 mm Hg, respectively. Bowfins were only moderately responsive to ANG II in a stepwise manner and the increase in blood pressure became significant only at the two highest doses; lower doses tended only to increase arterial pressure. Pressor responses due to 200 and 500 ng.kg-1 decayed over a greater time period compared with other doses. alpha-Adrenergic blockade abolished 70% of the ANG II-mediated pressor responses. Eel, salmon, and goosefish angiotensin I (ANG I; 500 ng.kg-1) elicited similar vasopressor responses (magnitude and time course) which were eliminated by prior angiotensin converting enzyme inhibition (captopril; 2-10 mg.kg-1). Bullfrog ANG I evoked a pressor effect, only at a higher dose (5000 ng.kg-1). Consecutive norepinephrine (NE) injections (100, 200, 500, and 1000 ng.kg-1) increased PSYS, PDIAS, and PDA in a dose-dependent manner which was dependent on alpha-adrenoceptors since phentolamine (1-3 mg.kg-1) abolished 80% of the pressor action of NE. PSYS was elevated by 100 ng.kg-1 of NE but PDIAS and PDA were significantly increased only at 200 ng.kg-1 ANG II and NE had no measurable chronotropic effect and resting HR (27.2 +/- 0.8 beats.min-1) was unchanged. Captopril and phentolamine treatments produced rapid hypotension and bradycardia (25-30%) which lasted from 15 to 30 and 20 to 40 min, respectively. The rising and decreasing phases of the NE-mediated pressor responses had shorter durations than ANG II effects. Tachyphylaxis occurred with the high doses of ANG II and NE. The data show that in the ancient bowfin, which evidently lacks renal juxtaglomerular cells, the cardiovascular system can be regulated by the renin-angiotensin system and NE.
Zhao, Feng; Bosserhoff, Anja-Katrin; Buettner, Reinhard; Moser, Markus
2011-01-01
Background Patent ductus arteriosus (PDA) is one of the most common forms of congenital heart disease. Mutations in transcription factor TFAP2B cause Char syndrome, a human disorder characterized by PDA, facial dysmorphysm and hand anomalies. Animal research data are needed to understand the mechanisms. The aim of our study was to elucidate the pathogenesis of Char syndrome at the molecular level. Methodology/Principal Findings Gene expression of Tfap2b during mouse development was studied, and newborns of Tfap2b-deficient mice were examined to identify phenotypes. Gel shift assays had been carried out to search for Tfap2 downstream genes. Promoters of candidate genes were cloned into a reporter construct and used to demonstrate their regulation by Tfap2b in cell transfection. In situ hybridizations showed that the murine transcription factor Tfap2b was expressed during the entire development of mouse ductus arteriosus. Histological examination of ductus arteriosus from Tfap2b knockout mice 6 hours after birth revealed that they were not closed. Consequently, the lungs of Tfap2b −/− mice demonstrated progressive congestion of the pulmonary capillaries, which was postulated to result secondarily from PDA. In addition, Tfap2b was expressed in the limb buds, particularly in the posterior limb field during development. Lack of Tfap2b resulted in bilateral postaxial accessory digits. Further study indicated that expressions of bone morphogenetic protein (Bmp) genes, which are reported to be involved in the limb patterning and ductal development, were altered in limb buds of Tfap2b-deficient embryos, due to direct control of Bmp2 and Bmp4 promoter activity by Tfap2b. Conclusions/Significance Tfap2b plays important roles in the development of mouse ductus arteriosus and limb patterning. Loss of Tfap2b results in altered Bmp expression that may cause the heart-limb defects observed in Tfap2b mouse mutants and Char syndrome patients. The Tfap2b knockout mouse may add to the very limited available animal models of PDA. PMID:21829553
Patent ductus arteriosus in premature infants: to treat or not to treat?
Mohamed, M A; El-Dib, M; Alqahtani, S; Alyami, K; Ibrahim, A N; Aly, H
2017-06-01
Closing patent ductus arteriosus (PDA) is a widely accepted approach in the management of very low birth weight (VLBW) infants. Our objective is to test the hypothesis that conservative management (no treatment) of PDA will not affect survival without chronic lung diseases (CLD). This retrospective study utilizes a prospectively collected database to compare two cohorts of VLBW infants. Infants in the first group (2001 to 2009) had their PDA treated with pharmacological and if necessary with surgical ligation. PDA in the second group (2010 to 2014) was not treated with medical or surgical intervention. The primary outcome was survival without oxygen requirement at 36 weeks. Pulmonary and non-pulmonary morbidities were also compared. Logistic regression analyses were performed to control for confounders. This study included 643 VLBW infants, of them 415 infants in the Treat group and 228 in the No-Treat group. The rate of survival without CLD did not differ between Treat and No-Treat groups (78.4% vs 83.9%, respectively; adjusted odds ratio (aOR)=1.72, confidence interval (CI): 0.92 to 3.23, P=0.09). Mortality declined in No-Treat group (15.2% vs 10.5%, aOR=0.51, CI: 0.25 to 0.99, P=0.049), but the two groups did not differ in the incidence of CLD among survivors (5.8% vs 5.0%,=P0.47). Pulmonary complications and non-pulmonary morbidities did not differ between groups. Conservative management (no treatment) of PDA may not compromise survival without CLD and is not associated with increased morbidities in VLBW infants. Prospective physiological studies are needed to determine the sector of VLBW infants, if any, who could benefit from PDA treatment.
Hsu, Kai-Hsiang; Wu, Tai-Wei; Wu, I-Hsyuan; Lai, Mei-Yin; Hsu, Shih-Yun; Huang, Hsiao-Wen; Mok, Tze-Yee; Lien, Reyin
2017-01-01
Electrical cardiometry (EC) is an impedance-based monitoring that provides noninvasive cardiac output (CO) assessment. Through comparison to transthoracic echocardiography (Echo), the accuracy of EC has been verified. However, left-to-right patent ductus arteriosus (PDA) shunting is a concern because PDA shunts aortic flow to the pulmonary artery and may interfere with EC in measuring CO. To determine the agreement between EC and Echo in preterm infants with a hemodynamically significant PDA (hsPDA). We reviewed our hemodynamic database in which simultaneous CO measurements by Echo and EC (Aesculon®) were recorded. Preterm infants with left-to-right shunting hsPDA were enrolled. A total of 105 paired measurements in 36 preterm infants were compared. Infants' median (range) age and weight at measurement were 27+2 weeks (24+0-33+1) and 1,015 g (518-1,880), with mean (95% CI) ductal diameter 2.11 mm (1.99-2.22) or 2.15 mm/kg (2.00-2.30). Mean COEC and COEcho were 252 ± 32 and 258 ± 45 mL/kg/min, respectively, which demonstrated a moderate correlation and without a significant between-measurement difference. Bland-Altman analysis showed a bias, limits of agreement, and error percentage of -5.3 mL/kg/min, -78.3 to 67.7 mL/kg/min, and 28.6%, respectively. There was a trend of increased bias and error percentage of infants with high CO ≥280 mL/kg/min and supported with high-frequency ventilator. EC and Echo have a wide but clinically acceptable agreement in measuring CO in preterm infants with hsPDA. However, for infants with high CO or ventilated by high-frequency ventilation, interpretation of COEC should be approached with caution. © 2017 S. Karger AG, Basel.
Davidson, Jaime A; Rosales, Aracely; Shillington, Alicia C; Bailey, Robert A; Kabir, Chris; Umpierrez, Guillermo E
2015-01-01
Purpose To describe the cultural and linguistic adaptation and Spanish translation of an English-language patient decision aid (PDA) for use in supporting shared decision-making in Hispanics/Latinos with type 2 diabetes mellitus (T2DM), a group at a high risk for complications. Patients and methods A steering committee of endocrinologists, a primary care physician, a certified diabetes educator, and a dietician, each with extensive experience in providing care to Hispanics/Latinos was convened to assess a PDA developed for English-speaking patients with T2DM. English content was reviewed for cultural sensitivity and appropriateness for a Hispanic/Latino population. A consensus-building process and iterative version edits incorporated clinician perspectives. The content was adapted to be consistent with traditional Hispanic/Latino cultural communication precepts (eg, avoidance of hostile confrontation; value for warm interaction; respect for authority; value of family support for decisions). The PDA was translated by native-speaking individuals with diabetes expertise. Results The PDA underwent testing during cognitive interviews with ten Spanish-speaking Hispanics/Latinos with T2DM to ensure that the content is reflective of the experience, understanding, and language Hispanic/Latino patients use to describe diabetes and treatment. Content edits were made to assure a literacy level appropriate to the audience, and the PDA was produced for online video dissemination. Conclusion High-quality, well-developed tools to facilitate shared decision-making in populations with limited access to culturally sensitive information can narrow gaps and align care with individual patient preferences. A newly developed PDA is available for shared decision-making that provides culturally appropriate treatment information for inadequately controlled Hispanics/Latinos with T2DM. The impact on the overall health of patients and care management of T2DM requires further study. PMID:25995623
Chen, Chun-Teh; Martin-Martinez, Francisco J.; Jung, Gang Seob
2017-01-01
A set of computational methods that contains a brute-force algorithmic generation of chemical isomers, molecular dynamics (MD) simulations, and density functional theory (DFT) calculations is reported and applied to investigate nearly 3000 probable molecular structures of polydopamine (PDA) and eumelanin. All probable early-polymerized 5,6-dihydroxyindole (DHI) oligomers, ranging from dimers to tetramers, have been systematically analyzed to find the most stable geometry connections as well as to propose a set of molecular models that represents the chemically diverse nature of PDA and eumelanin. Our results indicate that more planar oligomers have a tendency to be more stable. This finding is in good agreement with recent experimental observations, which suggested that PDA and eumelanin are composed of nearly planar oligomers that appear to be stacked together via π–π interactions to form graphite-like layered aggregates. We also show that there is a group of tetramers notably more stable than the others, implying that even though there is an inherent chemical diversity in PDA and eumelanin, the molecular structures of the majority of the species are quite repetitive. Our results also suggest that larger oligomers are less likely to form. This observation is also consistent with experimental measurements, supporting the existence of small oligomers instead of large polymers as main components of PDA and eumelanin. In summary, this work brings an insight into the controversial structure of PDA and eumelanin, explaining some of the most important structural features, and providing a set of molecular models for more accurate modeling of eumelanin-like materials. PMID:28451292
Yang, Ke; Huang, Xingyi; Fang, Lijun; He, Jinliang; Jiang, Pingkai
2014-12-21
Flexible nanodielectric materials with high dielectric constant and low dielectric loss have huge potential applications in the modern electronic and electric industry. Graphene sheets (GS) and reduced-graphene oxide (RGO) are promising fillers for preparing flexible polymer-based nanodielectric materials because of their unique two-dimensional structure and excellent electrical and mechanical properties. However, the easy aggregation of GS/RGO significantly limits the potential of graphene in enhancing the dielectric constant of polymer composites. In addition, the poor filler/matrix nanoscale interfacial adhesion also causes difficulties in suppressing the dielectric loss of the composites. In this work, using a facile and environmentally friendly approach, polydopamine coated RGO (PDA-RGO) and fluoro-polymer functionalized RGO (PF-PDA-RGO) were prepared. Compared with the RGO prepared by the conventional methods [i.e. hydrazine reduced-graphene oxide (H-RGO)] and PDA-RGO, the resulting PF-PDA-RGO nanosheets exhibit excellent dispersion in the ferroelectric polymer matrix [i.e. poly(vinylidene fluoride-co-hexafluoro propylene), P(VDF-HFP)] and strong interfacial adhesion with the matrix, leading to a low percolation threshold (fc = 1.06 vol%) and excellent flexibility for the corresponding nanocomposites. Among the three nanocomposites, the P(VDF-HFP)/PF-PDA-RGO nanocomposites exhibited the optimum performance (i.e. simultaneously having high dielectric constant and low dielectric loss). For instance, at 1000 Hz, the P(VDF-HFP) nanocomposite sample with 1.0 vol% PF-PDA-RGO has a dielectric constant of 107.9 and a dielectric loss of 0.070, showing good potential for dielectric applications. Our strategy provides a new pathway to prepare high performance flexible nanodielectric materials.
Lashley, Mark A.; Ivanov, Alexander S.; Bryantsev, Vyacheslav S.; ...
2016-09-30
Studies of the complexation of new promising ligands with uranyl (UO 2 2+) and other seawater cations can aid the development of more efficient, selective, and robust sorbents for the recovery of uranium from seawater. Here, we propose that the ligand design principles based on structural preorganization can be successfully applied to obtain a dramatic enhancement in UO 2 2+ ion binding affinity and selectivity. This concept is exemplified through the investigation of the com-plexes of UO 2 2+, VO 2+, and VO 2+ with the highly preorganized ligand PDA (1,10-phenanthroline-2,9-dicarboxylic acid) using a combination of fluores-cence and absorbance techniques,more » along with den-sity functional theory (DFT) calculations. Moreover, the measured stability constant value, log K1, of 16.5 for the UO 2 2+/PDA complex is very high compared to uranyl complexes with other dicarboxylic ligands. Moreover, PDA exhibits strong selectivity for uranyl over vanadium ions, since the determined sta-bility constant values of the PDA complexes of the vanadium ions are quite low (V(IV) log K1 = 7.4, V(V) = 7.3). Finally, the structures of the corresponding UO 2 2+, VO 2+, and VO 2+ complexes with PDA were identified by systematic DFT calculations, and helped to interpret the stronger binding affinity for uranium over the vanadium ions. Due to its high chemical stability, selectivity, and structural preor-ganization for UO 2 2+ complexation, PDA is a very promising candidate that can be potentially used in the development of novel adsorbent materials for the selective extraction of uranium from sea-water.« less
NASA Astrophysics Data System (ADS)
Yu, Xu; Cheng, Gong; Zheng, Si-Yang
2016-05-01
In this paper, a multifunctional Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite catalyst with highly stabilized reactivity and magnetic recyclability was synthesized by a self-assembled method. The magnetic Fe3O4 nanoparticles were coated with a thin layer of the SiO2 to obtain a negatively charged surface. Then positively charged poly(ethyleneimine) polymer (PEI) was self-assembled onto the Fe3O4@SiO2 by electrostatic interaction. Next, negatively charged glutathione capped gold nanoparticles (GSH-AuNPs) were electrostatically self-assembled onto the Fe3O4@SiO2@PEI. After that, silver was grown on the surface of the nanocomposite due to the reduction of the dopamine in the alkaline solution. An about 5 nm thick layer of polydopamine (PDA) was observed to form the Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite was carefully characterized by the SEM, TEM, FT-IR, XRD and so on. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite shows a high saturation magnetization (Ms) of 48.9 emu/g, which allows it to be attracted rapidly to a magnet. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite was used to catalyze the reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP) as a model system. The reaction kinetic constant k was measured to be about 0.56 min-1 (R2 = 0.974). Furthermore, the as-prepared catalyst can be easily recovered and reused for 8 times, which didn’t show much decrease of the catalytic capability.
Custers, Deborah; Krakowska, Barbara; De Beer, Jacques O; Courselle, Patricia; Daszykowski, Michal; Apers, Sandra; Deconinck, Eric
2016-02-01
Counterfeit medicines are a global threat to public health. High amounts enter the European market, which is why characterization of these products is a very important issue. In this study, a high-performance liquid chromatography-photodiode array (HPLC-PDA) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) method were developed for the analysis of genuine Viagra®, generic products of Viagra®, and counterfeit samples in order to obtain different types of fingerprints. These data were included in the chemometric data analysis, aiming to test whether PDA and MS are complementary detection techniques. The MS data comprise both MS1 and MS2 fingerprints; the PDA data consist of fingerprints measured at three different wavelengths, i.e., 254, 270, and 290 nm, and all possible combinations of these wavelengths. First, it was verified if both groups of fingerprints can discriminate between genuine, generic, and counterfeit medicines separately; next, it was studied if the obtained results could be ameliorated by combining both fingerprint types. This data analysis showed that MS1 does not provide suitable classification models since several genuines and generics are classified as counterfeits and vice versa. However, when analyzing the MS1_MS2 data in combination with partial least squares-discriminant analysis (PLS-DA), a perfect discrimination was obtained. When only using data measured at 254 nm, good classification models can be obtained by k nearest neighbors (kNN) and soft independent modelling of class analogy (SIMCA), which might be interesting for the characterization of counterfeit drugs in developing countries. However, in general, the combination of PDA and MS data (254 nm_MS1) is preferred due to less classification errors between the genuines/generics and counterfeits compared to PDA and MS data separately.
Wireless remote control clinical image workflow: utilizing a PDA for offsite distribution
NASA Astrophysics Data System (ADS)
Liu, Brent J.; Documet, Luis; Documet, Jorge; Huang, H. K.; Muldoon, Jean
2004-04-01
Last year we presented in RSNA an application to perform wireless remote control of PACS image distribution utilizing a handheld device such as a Personal Digital Assistant (PDA). This paper describes the clinical experiences including workflow scenarios of implementing the PDA application to route exams from the clinical PACS archive server to various locations for offsite distribution of clinical PACS exams. By utilizing this remote control application, radiologists can manage image workflow distribution with a single wireless handheld device without impacting their clinical workflow on diagnostic PACS workstations. A PDA application was designed and developed to perform DICOM Query and C-Move requests by a physician from a clinical PACS Archive to a CD-burning device for automatic burning of PACS data for the distribution to offsite. In addition, it was also used for convenient routing of historical PACS exams to the local web server, local workstations, and teleradiology systems. The application was evaluated by radiologists as well as other clinical staff who need to distribute PACS exams to offsite referring physician"s offices and offsite radiologists. An application for image workflow management utilizing wireless technology was implemented in a clinical environment and evaluated. A PDA application was successfully utilized to perform DICOM Query and C-Move requests from the clinical PACS archive to various offsite exam distribution devices. Clinical staff can utilize the PDA to manage image workflow and PACS exam distribution conveniently for offsite consultations by referring physicians and radiologists. This solution allows the radiologist to expand their effectiveness in health care delivery both within the radiology department as well as offisite by improving their clinical workflow.
Philip, Ranjit; Waller, B Rush; Agrawal, Vijaykumar; Wright, Dena; Arevalo, Alejandro; Zurakowski, David; Sathanandam, Shyam
2016-02-01
The aim of this study was to describe and differentiate the morphology of patent ductus arteriosus (PDA) seen in children born prematurely from other PDA types. PDAs are currently classified as types A-E using the Krichenko's classification. Children born prematurely with a PDA morphology that did not fit this classification were described as Type F PDA. A review of 100 consecutive children who underwent transcatheter device closure of PDA was performed. The diameter and length (L) of the PDA and the device diameter (D) were indexed to the descending aorta (DA) diameter. Comparison of 26 Type F PDAs was performed against, 29 Type A, 7 Type C and 32 Type E PDAs. Children with Type F PDAs (median 27.5 weeks gestation) were younger during the device occlusion compared with types A, C, and E (median age: 6 vs. 32, 11, and 42 months; P = 0.002). Type F PDAs were longer and larger, requiring a relatively large device for occlusion than types A, C, and E (Mean L/DA: 1.88 vs. 0.9, 1.21, and 0.89, P ≤ 0.01 and Mean D/DA: 1.04 vs. 0.46, 0.87, and 0.34, P ≤0.01). The Amplatzer vascular plug-II (AVP-II) was preferred for occlusion of Type F PDAs (85%; P <0.001). Children born prematurely have relatively larger and longer PDAs. These "fetal type PDAs" are best classified separately. We propose to classify them as Type F PDAs to add to types A-E currently in use. The AVP-II was effective in occluding Type F PDAs. © 2015 Wiley Periodicals, Inc.
Behjati-Ardakani, Mostafa; Behjati-Ardakani, Mohammad-Amin; Hosseini, Seyed-Habibolla; Noori, Noormohammad
2013-01-01
Objective Patent ductus arteriosus (PDA) is one of the most frequently seen congenital heart diseases. Its closure is recommended because of the risk of infective endocardis, as well as morbidity and mortality in the long. The aim of this study was to assess the long term results of the transcatheter closure of PDA in infants using amplatzer duct occlude (ADO). Methods From May 2004 to September 2011, forty eight infants underwent transcatheter closure of PDA. A lateral or right anterior oblique view aortogram was done to locate PDA and to measure its size. Before discharge, repeat aortogram was performed to evaluate eventual residual shunt and to confirm the appropriate deployment of the ADO. Follow up evaluations were done with transthoracic echocardiography at discharge, 1 month, 6 months, 12 months and yearly thereafter. Findings The mean age of patients at procedure was 9.18±2.32 (range 3 to 12) months, mean weight 6.73±1.16 (range 4.5 to 10.1) kg. The PDA occluded completely in 20 out of the 48 patients. Twenty four patients had trivial or mild shunt and two patients had moderate residual shunt which disappeared in one patient within 24 hours and other patient with moderate shunt in 1 month. One patient (age 8 months) had mild LPA stenosis. The device emobolization occurred in two patients, immediately after the procedure in one and during night in the other patient Conclusion The long term results suggested that transcatheter closure of PDA using Amplatzer duct occluder is a safe and effective treatment in infants less than 1 year of age with minimal complications. PMID:24427494
Lehenbauer, David G; Fraser, Charles D; Crawford, Todd C; Hibino, Naru; Aucott, Susan; Grimm, Joshua C; Patel, Nishant; Magruder, J Trent; Cameron, Duke E; Vricella, Luca
2018-07-01
The safety of surgical closure of patent ductus arteriosus (PDA) in very low birth weight premature neonates has been questioned because of associated morbidities. However, these studies are vulnerable to significant bias as surgical ligation has historically been utilized as "rescue" therapy. The objective of this study was to review our institutions' outcomes of surgical PDA ligation. All neonates with operative weight of ≤1.00 kg undergoing surgical PDA ligation from 2003 to 2015 were analyzed. Records were queried to identify surgical complications, perioperative morbidity, and mortality. Outcomes included pre- and postoperative ventilator requirements, pre- and postoperative inotropic support, acute kidney injury, surgical complications, and 30-day mortality. One hundred sixty-six preterm neonates underwent surgical ligation. One hundred twenty-one (70.3%) had failed indomethacin closure. One hundred sixty-four (98.8%) patients required mechanical ventilation prior to surgery. At 17 postoperative days, freedom from the ventilator reached 50%. Of 109 (66.4%) patients requiring prolonged preoperative inotropic support, 59 (54.1%) were liberated from inotropes by postoperative day 1. Surgical morbidity was encountered in four neonates (2.4%): two (1.2%) patients had a postoperative pneumothorax requiring tube thoracostomy, one (0.6%) patient had a recurrent laryngeal nerve injury, and one (0.6%) patient had significant intraoperative bleeding. The 30-day all-cause mortality was 1.8% (n = 3); no deaths occurred intraoperatively. In this retrospective investigation, surgical PDA closure was associated with low 30-day mortality and minimal morbidity and resulted in rapid discontinuation of inotropic support and weaning from mechanical ventilation. Given the safety of this intervention, surgical PDA ligation merits consideration in the management strategy of the preterm neonate with a PDA.
Challenges in device closure of a large patent ductus arteriosus in infants weighing less than 6 kg.
Vijayalakshmi, I B; Chitra, Narasimhan; Praveen, Jayan; Prasanna, Simha Rao
2013-02-01
Transcatheter closure of patent ductus arteriosus (PDA) has replaced surgery in most institutions. Despite improvements in techniques and the devices available, closure of large PDA in very small infants remains a challenge. To assess the challenges, feasibility, and efficacy of device closure of large PDA, in infants weighing ≤6 kg. Analysis of device closure of a PDA was done in 61 infants ≤6 kg. Their ages, ranged from 9 days-12 months (mean 8.9 months), weight ranged from 2.2 to 6 kg (mean 5.3 kg), and PDA measured 3.2-8.7 mm (mean 4.8 mm). The fluoroscopy time was 3-18 minutes. The largest device used was 12 × 10 mm. Successful device placement was achieved in 60/61 infants (98.4%). Mild aortic obstruction occurred in 2 cases (3.3%), as the device got displaced towards the aorta after release. The device embolized in 2 cases (3.3%). In one it was retrieved by a novel method like fastening the screw in the aorta and was closed with a 4 × 6 ADO II. In the other infant, with a single kidney, died of uremia after device retrieval. Mild left pulmonary artery (LPA) obstruction occurred in one case (1.6%). Four cases (6.6%) had minor vascular complications. The postprocedure weight gain after 3 months was between 2.5 kg ± 250 mg. Device closure of large PDA in infants weighing ≤6 kg with left ventricular failure is challenging but possible, safe and effective. Retrieval of embolized device could be tricky. © 2012, Wiley Periodicals, Inc.
Białkowski, Jacek; Szkutnik, Małgorzata; Fiszer, Roland; Głowacki, Jan; Banaszak, Paweł; Zembala, Marian
2010-01-01
Transcatheter treatment has become the method of choice for treating many heart defects. Recently, Cardio-O-Fix occluder (COF) - a new, self-expandable nitinol wire-mesh device very similar to the Amplatzer device - has been introduced into clinical practice. To the best of our knowledge, this is the first publication related to its application. Five patients aged from six months to 69 years were included in the study: two with atrial septal defect (ASD), one with patent foramen ovale (PFO) after cryptogenic stroke, and two with patent ductus arteriosus (PDA). These latter two comprised one six month old infant with co-existent hypertrophied cardiomyopathy, and a 53 year-old woman with recanalized PDA after previous ligation. All were treated percutaneously with COF. There was no preliminary patient selection. The only limitation was the size of the devices in our possession (16 and 22 mm ASD COF, 25 PFO COF, 4/6 and 6/8 PDA COF). The implantation technique was the same as previously described for Amplatzer occluders. All procedures were finished successfully with complete closure of the shunt. No complications were observed during a six month follow-up. In the child with PDA, we observed decrease of gradient from 80 to 60 mm Hg in hypertrophied left ventricular outflow tract, although a small protrusion of PDA-COF device was noted in the descending aorta (8 mm Hg gradient in ECHO). In the patient with recanalized PDA, the procedure was performed after arterio-venous loop creation. Mean fluoroscopy time was 4.4 (range from 1.6 to 11) minutes. Our preliminary experience indicates that the application of Cardio-O-Fix devices is safe and effective.
Mahfouz, Ragab A.; Alzaiat, Ahmad; Gad, Marwa
2014-01-01
Objectives We evaluated the influence of device closure for patent ductus arteriosus (PDA) on the aortic stiffness index (ASI) and brain natriuretic peptide (BNP) and their association with cardiac function. Patients and methods ASI and echocardiography assessment before and after treatment (16 ± 9 months) in 48 children with PDA (mean age 10 ± 4.5) and 52 control children (mean age 9.7 ± 4.6). BNP level was measured pre-closure for all children, and was measured six months after closure only for children with PDA. Results ASI was higher in PDA patients than in controls (P < 0.001). ASI correlated with age (P < 0.05), LVEF% (P < 0.01), E/E′ (<0.03), pulmonary artery pressure (P < 0.001), and BNP (P < 0.001). ASI and BNP significantly decreased after closure (P < 0.001). ASI and BNP were independent predictors for post-closure systolic dysfunction (P < 0.001and <0.005, respectively). Receiver operating curve (ROC) analysis showed that ASI ⩾ 13.5, BNP level ⩾75 pg/ml and basal mean pulmonary artery pressure (PAP) ⩾ 23 were powerful predictors for post-closure systolic function. Conclusion ASI is significantly associated with BNP and basal PAP in children with PDA. After device closure, aortic distensibility improved significantly and was associated with significant improvement in both systolic and diastolic functions. ASI can be used for monitoring the course of patients with PDA, and may give opportunities for early intervention. PMID:25544819
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lashley, Mark A.; Ivanov, Alexander S.; Bryantsev, Vyacheslav S.
Studies of the complexation of new promising ligands with uranyl (UO 2 2+) and other seawater cations can aid the development of more efficient, selective, and robust sorbents for the recovery of uranium from seawater. Here, we propose that the ligand design principles based on structural preorganization can be successfully applied to obtain a dramatic enhancement in UO 2 2+ ion binding affinity and selectivity. This concept is exemplified through the investigation of the com-plexes of UO 2 2+, VO 2+, and VO 2+ with the highly preorganized ligand PDA (1,10-phenanthroline-2,9-dicarboxylic acid) using a combination of fluores-cence and absorbance techniques,more » along with den-sity functional theory (DFT) calculations. Moreover, the measured stability constant value, log K1, of 16.5 for the UO 2 2+/PDA complex is very high compared to uranyl complexes with other dicarboxylic ligands. Moreover, PDA exhibits strong selectivity for uranyl over vanadium ions, since the determined sta-bility constant values of the PDA complexes of the vanadium ions are quite low (V(IV) log K1 = 7.4, V(V) = 7.3). Finally, the structures of the corresponding UO 2 2+, VO 2+, and VO 2+ complexes with PDA were identified by systematic DFT calculations, and helped to interpret the stronger binding affinity for uranium over the vanadium ions. Due to its high chemical stability, selectivity, and structural preor-ganization for UO 2 2+ complexation, PDA is a very promising candidate that can be potentially used in the development of novel adsorbent materials for the selective extraction of uranium from sea-water.« less
Meijer, M; Beijerink, N J
2012-06-01
A left-to-right shunting patent ductus arteriosus (PDA) is a common congenital heart defect in dogs. If it is left uncorrected, life expectancy in most cases is decreased due to the development of left-sided congestive heart failure. The aim of this study was to describe the dogs diagnosed with PDA in the Utrecht University Companion Animal Clinic from 2003 to 2011. The medical records of 102 patients were retrieved, and the clinical presentation and outcome of PDA closure by surgical ligation or transarterial catheter occlusion (TCO) were reviewed. In the TCO group, the result of coiling was compared with the placement of an Amplatz Canine Duct Occluder (ACDO). A predisposition to PDA was found in the German Brak, Stabyhoun, and Schapendoes. Dogs treated with surgical ligation were significantly older and heavier than those treated with TCO; within the TCO group, dogs treated with ACDO were significantly older and heavier The initial success rate (complete disappearance of the audible murmur in a patient that survived the procedure) was not significantly different between the different treatment modalities. Major complications were more common with surgical ligation, but the incidence of minor complications was not significantly different. There was no diference in survival between dogs treated with surgical ligation and dogs treated with TCO. This study shows a previously unreported predisposition to PDA in certain breeds. Both surgical ligation and TCO are suitable techniques for PDA closure, although major complications were more common with surgical ligation. ACDO appears to be the method with the least complications and thus can be considered the safest method.
Shillington, Alicia C; Col, Nananda; Bailey, Robert A; Jewell, Mark A
2015-01-01
Purpose To describe the process used to develop an evidence-based patient decision aid (PDA) that facilitates shared decision-making for treatment intensification in inadequately controlled type 2 diabetes mellitus (T2DM) consistent with International Patient Decision Aids Standards. Methods A PDA was developed by a multidisciplinary steering committee of clinicians, patient advocate, nurse, certified diabetes educators, and decision scientist, using a systematic development process. The process included defining the PDA scope and purpose, outlining the framework, content creation, and designing for integration into clinical practice. This was accomplished through a review of the literature and publically available educational materials and input from practicing clinicians and patients during development and iteratively refining content based on input. Patients with poorly controlled T2DM on metformin considering additional medication assessed the PDA during a pilot. Results Testing identified six preference-sensitive domains important for choosing T2DM treatment: degree of glycemic response, avoiding weight gain, hypoglycemia risk and other adverse events, avoiding injections, convenience of dose administration, blood glucose monitoring, and cost of therapy. Patient feedback guided content revision. Treatment options were offered after presenting medication class risk–benefit information and eliciting patient values, goals, and preferences. The PDA received the highest International Patient Decision Aids Standards global score to date, 88/100, with 100% of criteria fully met for the following dimensions: development process, disclosures, evaluation process, evidence quality, guidance for users, information quality, language/readability, testing, and eliciting patient values. Conclusion A PDA was developed to help T2DM patients make decisions regarding medication choice. This approach may be applicable to other chronic conditions. PMID:25995622
Davidson, Jaime A; Rosales, Aracely; Shillington, Alicia C; Bailey, Robert A; Kabir, Chris; Umpierrez, Guillermo E
2015-01-01
To describe the cultural and linguistic adaptation and Spanish translation of an English-language patient decision aid (PDA) for use in supporting shared decision-making in Hispanics/Latinos with type 2 diabetes mellitus (T2DM), a group at a high risk for complications. A steering committee of endocrinologists, a primary care physician, a certified diabetes educator, and a dietician, each with extensive experience in providing care to Hispanics/Latinos was convened to assess a PDA developed for English-speaking patients with T2DM. English content was reviewed for cultural sensitivity and appropriateness for a Hispanic/Latino population. A consensus-building process and iterative version edits incorporated clinician perspectives. The content was adapted to be consistent with traditional Hispanic/Latino cultural communication precepts (eg, avoidance of hostile confrontation; value for warm interaction; respect for authority; value of family support for decisions). The PDA was translated by native-speaking individuals with diabetes expertise. The PDA underwent testing during cognitive interviews with ten Spanish-speaking Hispanics/Latinos with T2DM to ensure that the content is reflective of the experience, understanding, and language Hispanic/Latino patients use to describe diabetes and treatment. Content edits were made to assure a literacy level appropriate to the audience, and the PDA was produced for online video dissemination. High-quality, well-developed tools to facilitate shared decision-making in populations with limited access to culturally sensitive information can narrow gaps and align care with individual patient preferences. A newly developed PDA is available for shared decision-making that provides culturally appropriate treatment information for inadequately controlled Hispanics/Latinos with T2DM. The impact on the overall health of patients and care management of T2DM requires further study.
The Society of Toxicology (SOT) established the Postdoctoral Assembly (PDA) to identify and meet the needs of postdoctoral scholars, establish communication, and form collaborations within the SOT members. The PDA currently has representatives on key SOT committees and component ...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-24
... Commission has subject matter jurisdiction and that Apple did not contest that the Commission has in rem and... PDA system from normal mode to sleep mode when the PDA system has been idle for a second period of...
Carbon Fibers with Controlled Surface Chemistry
1992-04-15
1991 Approved for Public Release; Distribution is Unlimited. Prepared for PDA ENGINEERING 2975 Redhill Avenue Costa Mesa, CA 92626 93-2 51’M 505...SPONSORING/ MONITORING AGENCY REPORT NUMBER PDA ENGINEERING 2975 Redhill Avenue Costa Mesa, CA 92626 11. SUPPLEMENTARY NOTES TPL, Inc. 3754 Hawkins, NE