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Sample records for amp prolongs graft

  1. Cyclic AMP system in muscle tissue during prolonged hypokinesia

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    Antipenko, Y. A.; Bubeyev, Y. A.; Korovkin, B. F.; Mikhaleva, N. P.

    1980-01-01

    Components of the cyclic Adenosine-cyclic-35-monophosphate (AMP) system in the muscle tissue of white rats were studied during 70-75 days of hypokinesia, created by placing the animals in small booths which restricted their movements, and during the readaptation period. In the initial period, cyclic AMP levels and the activities of phosphodiesterase and adenylate cyclase in muscle tissue were increased. The values for these indices were roughly equal for controls and experimental animals during the adaptation period, but on the 70th day of the experiment cAMP levels dropped, phosphodiesterase activity increased, and the stimulative effect of epinephrine on the activity of adenylate cyclase decreased. The indices under study normalized during the readaptation period.

  2. Prolongation of allogeneic skin graft survival by injection of anti-Ly49A monoclonal antibody YE1/48.

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    Yang, Tian-Yu; Sun, Yimin; Langnas, Alan N; Zhao, Yong

    2003-02-01

    Ly49A receptors expressed on NK, NKT, and T cells play inhibitory roles in regulating the immune responses in vivo and in vitro. Whether or not injection of anti-Ly49A monoclonal antibody (mAb) YE1/48 can block allograft rejection has not been evaluated. Balb/c mouse recipients received intraperitoneal injections of YE1/48 mAb (0.5 mg) or control mAb or phosphate-buffered saline on days -1 and 10. On day 0, fully MHC-mismatched allogeneic C57BL/6 (B6) skin grafts were implanted. The skin graft survival and anti-donor humoral responses were observed. Whereas allogeneic B6 skin grafts survived 14 days in isotopy control antibody-treated or nontreated Balb/c mice, injection of YE1/48 mAb significantly prolonged B6 skin graft survival to 19 days (P < 0.0005). Injection of YE1/48 mAb into presensitized Balb/c recipients did not significantly delay B6 skin graft rejection. On the other hand, after depleting recipient NK, NKT, and some cytotoxic T cells by injection of anti-asialo GM1, YE1/48 failed to prolong B6 skin graft survival in Balb/c recipients. The present studies indicate that injection of YE1/48 mAb significantly delays allogeneic skin graft rejection in nonsensitized recipients but not in sensitized recipients. The presence of NK, NKT cells, and some cytotoxic T cells may be essential for YE1/48-mediated immunosuppression in vivo.

  3. Overexpression of thioredoxin in islets transduced by a lentiviral vector prolongs graft survival in autoimmune diabetic NOD mice

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    Sytwu Huey-Kang

    2009-08-01

    Full Text Available Abstract Pancreatic islet transplantation is considered an appropriate treatment to achieve insulin independence in type I diabetic patients. However, islet isolation and transplantation-induced oxidative stress and autoimmune-mediated destruction are still the major obstacles to the long-term survival of graft islets in this potential therapy. To protect islet grafts from inflammatory damage and prolong their survival, we transduced islets with an antioxidative gene thioredoxin (TRX using a lentiviral vector before transplantation. We hypothesized that the overexpression of TRX in islets would prolong islet graft survival when transplanted into diabetic non-obese diabetic (NOD mice. Methods Islets were isolated from NOD mice and transduced with lentivirus carrying TRX (Lt-TRX or enhanced green fluorescence protein (Lt-eGFP, respectively. Transduced islets were transplanted under the left kidney capsule of female diabetic NOD mice, and blood glucose concentration was monitored daily after transplantation. The histology of the islet graft was assessed at the end of the study. The protective effect of TRX on islets was investigated. Results The lentiviral vector effectively transduced islets without altering the glucose-stimulating insulin-secretory function of islets. Overexpression of TRX in islets reduced hydrogen peroxide-induced cytotoxicity in vitro. After transplantation into diabetic NOD mice, euglycemia was maintained for significantly longer in Lt-TRX-transduced islets than in Lt-eGFP-transduced islets; the mean graft survival was 18 vs. 6.5 days (n = 9 and 10, respectively, p Conclusion We successfully transduced the TRX gene into islets and demonstrated that these genetically modified grafts are resistant to inflammatory insult and survived longer in diabetic recipients. Our results further support the concept that the reactive oxygen species (ROS scavenger and antiapoptotic functions of TRX are critical to islet survival after

  4. Perioperative risk factors for prolonged mechanical ventilation and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass

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    Zahra S Faritous

    2011-01-01

    Full Text Available Background: Prolonged mechanical ventilation is an important recognized complication occurring during cardiovascular surgery procedures. This study was done to assess the perioperative risk factors related to postoperative pulmonary complications and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass. Methods: It was a retrospective study on 5,497 patients, including 31 patients with prolonged ventilatory support and 5,466 patients without it; from the latter group, 350 patients with normal condition (extubated in 6-8 hours without any complication were selected randomly. Possible perioperative risk factors were compared between the two groups using a binary logistic regression model. Results: Among the 5,497 women undergoing coronary artery bypass graft (CABG, 31 women needed prolonged mechanical ventilation (PMV, and 15 underwent tracheostomy. After logistic regression, 7 factors were determined as being independent perioperative risk factors for PMV. Discussion: Age ≥70 years old, left ventricular ejection fraction (LVEF ≤30%, preexisting respiratory or renal disease, emergency or re-do operation and use of preoperative inotropic agents are the main risk factors determined in this study on women undergoing CABG.

  5. Chondrocyte viability is higher after prolonged storage at 37 degrees C than at 4 degrees C for osteochondral grafts.

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    Pallante, Andrea L; Bae, Won C; Chen, Albert C; Görtz, Simon; Bugbee, William D; Sah, Robert L

    2009-11-01

    Osteochondral allografts are currently stored at 4 degrees C for 2 to 6 weeks before implantation. At 4 degrees C, chondrocyte viability, especially in the superficial zone, deteriorates starting at 2 weeks. Alternative storage conditions could maintain chondrocyte viability beyond 2 weeks, and thereby facilitate increased graft availability and enhanced graft quality. The objective of the study was to determine the effects of prolonged 37 degrees C storage compared with traditional 4 degrees C storage on chondrocyte viability and cartilage matrix content. Controlled laboratory study. Osteochondral samples from humeral heads of adult goats were analyzed (i) fresh, or after storage in medium for (ii) 14 days at 4 degrees C including 10% fetal bovine serum, (iii) 28 days at 4 degrees C including 10% fetal bovine serum, (iv) 28 days at 37 degrees C without fetal bovine serum, (v) 28 days at 37 degrees C including 2% fetal bovine serum, or (vi) 28 days at 37 degrees C including 10% fetal bovine serum. Portions of samples were analyzed by microscopy after LIVE/DEAD staining to determine chondrocyte viability and density, both en face (to visualize the articular surface) and vertically (overall and in superficial, middle, and deep zones). The remaining cartilage was analyzed for sulfated glycosaminoglycan and collagen. The 37 degrees C storage maintained high chondrocyte viability compared with 4 degrees C storage. Viability of samples after 28 days at 37 degrees C was approximately 80% at the cartilage surface en face, approximately 65% in the superficial zone, and approximately 70% in the middle zone, which was much higher than approximately 45%, approximately 20%, and approximately 35%, respectively, in 4 degrees C samples after 28 days, and slightly decreased from approximately 100%, approximately 85%, and approximately 95%, respectively, in fresh controls. Cartilage thickness, glycosaminoglycan content, and collagen content were maintained for 37 degrees C and 4

  6. Recipient bone marrow-derived stromal cells prolong graft survival in a rat hind limb allotransplantation model.

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    Ikeguchi, Ryosuke; Kakinoki, Ryosuke; Ohta, Souichi; Oda, Hiroki; Yurie, Hirofumi; Kaizawa, Yukitoshi; Mitsui, Hiroto; Aoyama, Tomoki; Toguchida, Junya; Matsuda, Shuichi

    2017-09-01

    Recent studies have indicated that bone marrow-derived stromal cells (BMSCs) have immunomodulatory properties that suppress the T cell responses that cause graft rejection. The purpose of this study is to evaluate the effect of recipient BMSCs intravenous infusion for immunomodulation in a rat vascularized composite allotransplantation model. A total of nine Wistar (WIS) rats and thirty Lewis (LEW) rats were used. BMSCs were harvested from three LEW rats. Twenty-four LEW rats were used as recipients and divided randomly into four groups: BMSC group, FK group, UT group, and Iso group. In the BMSC group, orthotopic rat hind limb transplantation was performed between WIS donor and LEW recipient rats. Recipient rats were injected intravenously with 2 × 10 6 recipient BMSCs on day 6, and with 0.2 mg/kg/day tacrolimus administered over 7 days (n = 6). In the FK group, recipient rats were treated with tacrolimus alone (n = 6). Rats in the UT group received no immunosuppressive treatment (n = 6). In the Iso group, transplantation was performed from three LEW donor rats to six LEW recipient rats without any immunosuppressive treatment (n = 6). Graft survival was assessed by daily inspection and histology. The immunological reactions of recipients were also evaluated. The graft survival of recipient rats in the BMSC group (24.5 days) was significantly prolonged in comparison with that of the FK group (18 days) (P Recipient rats in the BMSC group had significantly reduced serum IFN-γ cytokine levels (1.571 ± 0.779 pg/ml) in comparison with that of the FK group (7.059 ± 1.522 pg/ml) (P = .001). In in vitro study, BMSCs induce T cell hyporesponsiveness in a mixed lymphocyte reaction. BMSCs induce T cell hyporesponsiveness and prolong graft survival in the rat vascularized composite allotransplantation model. BMSCs exhibit immunomodulatory properties against acute rejection that can be realized without the need for significant recipient

  7. Controlled release of moxifloxacin from intraocular lenses modified by Ar plasma-assisted grafting with AMPS or SBMA: An in vitro study.

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    Pimenta, A F R; Vieira, A P; Colaço, R; Saramago, B; Gil, M H; Coimbra, P; Alves, P; Bozukova, D; Correia, T R; Correia, I J; Guiomar, A J; Serro, A P

    2017-08-01

    Intraocular lenses (IOLs) present an alternative for extended, local drug delivery in the prevention of post-operative acute endophthalmitis. In the present work, we modified the surface of a hydrophilic acrylic material, used for manufacturing of IOLs, through plasma-assisted grafting copolymerization of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) or [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA), with the aim of achieving a controlled and effective drug release. The material was loaded with moxifloxacin (MFX), a commonly used antibiotic for endophthalmitis prevention. The characterization of the modified material showed that relevant properties, like swelling capacity, wettability, refractive index and transmittance, were not affected by the surface modification. Concerning the drug release profiles, the most promising result was obtained when AMPS grafting was done in the presence of MFX. This modification led to a higher amount of drug being released for a longer period of time, which is a requirement for the prevention of endophthalmitis. The material was found to be non-cytotoxic for rabbit corneal endothelial cells. In a second step, prototype IOLs were modified with AMPS and loaded with MFX as previously and, after sterilization and storage (30days), they were tested under dynamic conditions, in a microfluidic cell with volume and renovation rate similar to the eye aqueous humour. MFX solutions collected in this assay were tested against Staphylococcus aureus and Staphylococcus epidermidis and the released antibiotic proved to be effective against both bacteria until the 12th day of release. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Yogurt Feeding Induced the Prolongation of Fully Major Histocompatibility Complex-Mismatched Murine Cardiac Graft Survival by Induction of CD4+Foxp3+ Cells.

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    Uchiyama, M; Yin, E; Yanagisawa, T; Jin, X; Hara, M; Matsuyama, S; Imazuru, T; Uchida, K; Kawamura, M; Niimi, M

    Yogurt is a nutrient-rich food and the beneficial effects of yogurt on both health and immunomodulatory effects are well documented. In this pilot study, we investigated the effects of commercially produced yogurt R-1 on alloimmune responses in a murine cardiac transplantation model. The R-1 is produced by Meiji Co., Ltd., and contains live and active lactic acid bacteria (lactobacillus bulgaricus OLL1073R-1) mainly. CBA (H2 k ) mice underwent transplantation of a C57BL/6 (H2 b ; B6) heart and received oral administration of 1 mL, 0.1 mL, and 0.01 mL of R-1 from the day of transplantation until 7 days afterward. Additionally, we prepared one group of CBA recipients given 1 mL of R-1 sterilized by microwave for 7 days. Histological and immunohistochemical studies were performed. Naïve CBA mice rejected B6 cardiac graft acutely (median survival time [MST]: 7 days). CBA recipients given of 1 mL of R-1 had significantly prolonged B6 allograft survival (MST, 27 days). However, other doses of 0.1 mL and 0.01 mL of R-1 did not prolonged allograft survival (MSTs, 9 days and 8.5 days, respectively). Also, CBA recipients administered microwaved R-1 had no prolongation of B6 allograft (MST, 9 days). Histological and immunohistochemical studies showed the cardiac allograft from R-1-exposed CBA recipients had preserved graft and vessel structure and the number of infiltrated CD4 + , CD8 + , and Foxp3 + cells in R-1-exposed CBA recipients increased, respectively. In conclusion, our findings imply that yogurt containing active lactic acid bacteria could change alloimmune responses partially and induce the prolongation of cardiac allograft survival via CD4 + Foxp3 + regulatory cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Low-dose G-CSF improves fat graft retention by mobilizing endogenous stem cells and inducing angiogenesis, whereas high-dose G-CSF inhibits adipogenesis with prolonged inflammation and severe fibrosis.

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    Cai, Junrong; Li, Bin; Liu, Kaiyang; Feng, Jingwei; Gao, Kai; Lu, Feng

    2017-09-23

    Hematopoietic stem cells (HSCs) promote fat graft survival by modulating its revascularization. The authors hypothesize that mobilization of HSCs by G-CSF will improve fat graft survival. Hence, we evaluated the effect of different doses of G-CSF on fat grafting. Male 8-week-old C57 mice received high-dose G-CSF (100 μg/kg), low-dose G-CSF (10 μg/kg), and PBS (control) intraperitoneally for 7 consecutive days right after autologous fat grafting. Grafted fat was harvested at 1, 4, and 12 weeks for examination. The low-dose G-CSF, high-dose G-CSF, and control groups had retention rates of 73.6% ± 3.1%, 51.6% ± 4.4%, and 44.5% ± 4.0%, respectively, at 12 weeks (low-dose G-CSF versus control and low-dose G-CSF versus high-dose G-CSF, both p cells in fat grafts, contributing to improved angiogenesis. However, high-dose G-CSF caused a prolonged macrophage infiltration and elevated level of inflammation (IL-6 and TNF-α), which led to severe fibrosis and impaired adipogenesis (downregulated expression of PPAR-γ and CEBP-α). Low-dose G-CSF treatment successfully improved fat graft survival by mobilizing HSCs and inducing angiogenesis. However, high-dose G-CSF prolonged inflammation and caused severe fibrosis, leading to impaired adipogenesis and poor fat graft survival. Copyright © 2017. Published by Elsevier Inc.

  10. Nature of the suppressor cells mediating prolonged graft survival after administration of extracted histocompatibility antigen and cyclosporine

    International Nuclear Information System (INIS)

    Yoshimura, N.; Kahan, B.D.

    1985-01-01

    Antigen-specific suppressor T cells are induced by donor histocompatibility antigen extracted from spleen cells with 3M KCl combined with cyclosporine (Ag-CsA). A single i.v. injection of 5 mg 3M-KCl-extracted donor Buffalo (Buf, RT1b) antigen (Ag) combined with a three day course of CsA prolonged renal allograft survival in Wistar-Furth (WFu, RT1u) hosts to a greater extent (MST 26.5 days) than CsA alone (MST 11.8 days). Peripheral blood lymphocytes (PBL) or spleen cells harvested from Ag-CsA-treated recipients ten days after transplantation inhibited the mixed lymphocyte reaction (MLR) between normal responder WFu cells and irradiated Buf cells (55.6% and 64.4% suppression, respectively, P less than 0.025), but not third-party Brown-Norway (BN, RT1n) stimulator cells (13.6% and -18.3% suppression, respectively, NS). The suppressor effect was not mediated by cytolytic cells; there was neither primary nor secondary cytolytic activity against 51 Cr-labeled Con-A blastoid Buf cells. The suppressor cells were neither adherent to plastic dishes nor to nylon-wool columns. PBL irradiated with 800 rads, but not 1500 rads, suppressed the MLR. A single injection of cyclophosphamide (CY, 25 mg/kg) seven days after transplantation abrogated the suppression induced by Ag-CsA treatment. Moreover, PBL from Ag-CsA recipients failed to suppress the MLR, if depleted either of all T cells by treatment with monoclonal antibody (Mab) W3/13 HLK (pan T cells; % suppression -15.8), or of cytotoxic/suppressor cells with Mab OX-8 (-19.3% suppression) together with rabbit antimouse immunoglobulin and complement

  11. Stent graft placement for dysfunctional arteriovenous grafts

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    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  12. An Antigen-Presenting and Apoptosis-Inducing Polymer Microparticle Prolongs Alloskin Graft Survival by Selectively and Markedly Depleting Alloreactive CD8+ T Cells

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    Wei Wang

    2017-06-01

    Full Text Available Selectively depleting the pathogenic T cells is a fundamental strategy for the treatment of allograft rejection and autoimmune disease since it retains the overall immune function of host. The concept of killer artificial antigen-presenting cells (KaAPCs has been developed by co-coupling peptide–major histocompatibility complex (pMHC multimer and anti-Fas monoclonal antibody (mAb onto the polymeric microparticles (MPs to induce the apoptosis of antigen-specific T cells. But little information is available about its in vivo therapeutic potential and mechanism. In this study, polyethylenimine (PEI-coated poly lactic-co-glycolic acid microparticle (PLGA MP was fabricated as a cell-sized scaffold to covalently co-couple H-2Kb-Ig dimer and anti-Fas mAb for the generation of alloantigen-presenting and apoptosis-inducing MPs. Intravenous infusions of the biodegradable KaAPCs prolonged the alloskin graft survival for 43 days in a single MHC-mismatched murine model, depleted the most of H-2Kb-alloreactive CD8+ T cells in peripheral blood, spleen, and alloskin graft in an antigen-specific manner and anti-Fas-dependent fashion. The cell-sized KaAPCs circulated throughout vasculature into liver, kidney, spleen, lymph nodes, lung, and heart, but few ones into local allograft at early stage, with a retention time up to 36 h in vivo. They colocalized with CD8+ T cells in secondary lymphoid organs while few ones contacted with CD4+ T cells, B cells, macrophage, and dendritic cells, or internalized by phagocytes. Importantly, the KaAPC treatment did not significantly impair the native T cell repertoire or non-pathogenic immune cells, did not obviously suppress the overall immune function of host, and did not lead to visible organ toxicity. Our results strongly document the high potential of PLGA MP-based KaAPCs as a novel antigen-specific immunotherapy for allograft rejection and autoimmune disorder. The in vivo mechanism of alloinhibition, tissue

  13. Prolonged in vivo administration of testosterone-enanthate, the widely used and abused anabolic androgenic steroid, disturbs prolactin and cAMP signaling in Leydig cells of adult rats.

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    Bjelic, Maja M; Stojkov, Natasa J; Radovic, Sava M; Baburski, Aleksandar Z; Janjic, Marija M; Kostic, Tatjana S; Andric, Silvana A

    2015-05-01

    This study was designed to systematically analyze and define the effects of 1-day, 2-weeks, 10-weeks intramuscular administration of testosterone-enanthate, widely used and abused anabolic androgenic steroid (AAS), on main regulators of steroidogenesis and steroidogenic genes expression in testosterone-producing Leydig cells of adult rats. The results showed that prolonged (10-weeks) intramuscular administration of testosterone-enanthate, in clinically relevant dose, significantly increased prolactin, but decreased Prlr2 and Gnrhr in pituitary of adult rat. The levels of testosterone, Insl3, cAMP and mitochondrial membrane potential of Leydig cells were significantly reduced. This was followed by decreased expression of some steroidogenic enzymes and regulatory proteins such as Lhcgr, Prlr1/2, Tspo, Star, Cyp11a1, Cyp17a1, Dax1. Oppositely, Hsd3b1/2, Hsd3b5, Hsd17b4, Ar, Arr19 increased. In the same cells, transcriptional milieu of cAMP signaling elements was disturbed with remarkable up-regulation of PRKA (the main regulator of steroidogenesis). Increased prolactin together with stimulated transcription of Jak2/Jak3 could account for increased Hsd3b1/2 and Hsd3b5 in Leydig cells following 10-weeks in vivo treatment with testosterone-enanthate. In vitro studies revealed that testosterone is capable to increase level of Prlr1, Prlr2, Hsd3b1/2, Hsd3b5 in Leydig cells. Accordingly, testosterone-induced changes in prolactin receptor signaling together with up-regulation of PRKA, Hsd3b1/2, Hsd3b5, Ar in Leydig cells, could be the possible mechanism that contribute to the establishment of a new adaptive response to maintain homeostasis and prevent loss of steroidogenic function. Presented data provide new molecular insights into the relationship between disturbed testosterone homeostasis and mammalian reproduction and are important in terms of wide use and abuse of AASs and human reproductive health. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Cyclic AMP in rat pancreatic islets

    International Nuclear Information System (INIS)

    Grill, V.; Borglund, E.; Cerasi, E.; Uppsala Univ.

    1977-01-01

    The incorporation of [ 3 H]adenine into cyclic AMP was studied in rat pancreatic islets under varying conditions of labeling. Prolonging the exposure to [ 3 H]adenine progressively augmented the islet cyclic [ 3 H]AMP level. Islets labeled for different periods of time and subsequently incubated (without adenine) in the presence of D-glucose or cholera toxin showed stimulations of intra-islet cyclic [ 3 H]AMP that were proportionate to the levels of radioactive nucleotide present under non-stimulatory conditions. Labeling the islets in a high glucose concentration (27.7 mM) did not modify the nucleotide responses to glucose or cholera toxin. The specific activity of cyclic [ 3 H]AMP, determined by simultaneous assay of cyclic [ 3 H]AMP and total cyclic AMP, was not influenced by glucose or cholera toxin. Glucose had no effect on the specific activity of labeled ATP

  15. Biocompatibility of polypropylene non-woven fabric membrane via UV-induced graft polymerization of 2-acrylamido-2-methylpropane sulfonic acid

    International Nuclear Information System (INIS)

    Song Lingjie; Zhao Jie; Yang Huawei; Jin Jing; Li Xiaomeng; Stagnaro, Paola; Yin Jinghua

    2011-01-01

    This work described the graft polymerization of a sulfonic acid terminated monomer, 2-acrylamido-2-methylpropane sulfonic acid (AMPS), onto the surface of polypropylene non-woven (NWF PP) membrane by O 2 plasma pretreatment and UV-induced photografting method. The chemical structure and composition of the modified surfaces were analyzed by FTIR-ATR and XPS, respectively. The wettability was investigated by water contact angle and equilibrium water adsorption. And the biocompatibility of the modified NWF PP membranes was evaluated by protein adsorption and platelet adhesion. It was found that the graft density increased with prolonging UV irradiation time and increasing AMPS concentration; the water contact angles of the membranes decreased from 124 o to 26 o with the increasing grafting density of poly(AMPS) from 0 to 884.2 μg cm -2 , while the equilibrium water adsorption raised from 5 wt% to 75 wt%; the protein absorption was effectively suppressed with the introduction of poly(AMPS) even at the low grafting density (132.4 μg cm -2 ); the number of platelets adhering to the modified membrane was dramatically reduced when compared with that on its virgin surface. These results indicated that surface modification of NWF PP membrane with AMPS was a facile approach to construct biocompatible surface.

  16. Amine bridges grafted mesoporous silica, as a prolonged/controlled drug release system for the enhanced therapeutic effect of short life drugs

    International Nuclear Information System (INIS)

    Rehman, Fozia; Ahmed, Khalid; Airoldi, Claudio; Gaisford, Simon; Buanz, Asma; Rahim, Abdur; Muhammad, Nawshad; Volpe, Pedro L.O.

    2017-01-01

    Hybrid mesoporous silica SBA-15, with surface incorporated cross-linked long hydrophobic organic bridges was synthesized using stepwise synthesis. The synthesized materials were characterized by elemental analysis, infrared spectroscopy, nuclear magnetic resonance spectroscopy, nitrogen adsorption, X-rays diffraction, thermogravimetry and scanning and transmission electron microscopy. The functionalized material showed highly ordered mesoporous network with a surface area of 629.0 m 2 g −1 . The incorporation of long hydrophobic amine chains on silica surface resulted in high drug loading capacity (21% Mass/Mass) and prolonged release of ibuprofen up till 75.5 h. The preliminary investigations suggests that the synthesized materials could be proposed as controlled release devices to prolong the therapeutic effect of short life drugs such as ibuprofen to increase its efficacy and to reduce frequent dosage. - Highlights: • Silica SBA-15 was synthesized and modified with long hydrophobic amine linkers. • These materials were characterized using different techniques. • The modified material showed high drug loading capacity and control ibuprofen release in biological fluids.

  17. cAMP-response Element-binding Protein (CREB) and NF-κB Transcription Factors Are Activated during Prolonged Hypoxia and Cooperatively Regulate the Induction of Matrix Metalloproteinase MMP1*

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    Nakayama, Koh

    2013-01-01

    Responses to low levels of oxygen (hypoxia) are essential to maintain homeostasis. During the hypoxic response, gene expression is altered by various transcription factors. The transcription factor, hypoxia-inducible factor (HIF), plays a central role in the hypoxic response. The α subunit of HIF, which is actively degraded during normoxia, becomes stabilized during hypoxia, which leads to HIF activation. A microarray analysis of HeLa cells showed that expression of matrix metalloproteinase 1 (MMP1) was markedly induced during prolonged hypoxia. CREB and NF-κB binding sites were identified in the MMP1 promoter region between 1945 and 1896 nucleotides upstream of the transcription start site. Assays with luciferase reporters demonstrated that HIF activity was induced during the early phase of hypoxia, whereas CREB and NF-κB were activated during the later (prolonged) phase. Depletion of CREB and/or NF-κB reduced MMP1 induction during prolonged hypoxia both at the mRNA and protein levels. A chromatin immunoprecipitation assay demonstrated binding of CREB and NF-κB to the MMP1 promoter. Finally, cell migration and invasion on a collagen matrix and pulmonary metastasis in nude mice were inhibited after depletion of CREB and NF-κB in MDA-MB-231 cells. Taken together, these results suggest that the cooperative action of CREB and NF-κB plays an important role to induce MMP1 expression during prolonged hypoxia and regulates cell migration and invasion in cancer cells. PMID:23775082

  18. Mesenchymal stem cells promote liver regeneration and prolong survival in small-for-size liver grafts: involvement of C-Jun N-terminal kinase, cyclin D1, and NF-κB.

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    Weijie Wang

    Full Text Available BACKGROUND: The therapeutic potential of mesenchymal stem cells (MSCs has been highlighted recently for treatment of acute or chronic liver injury, by possibly differentiating into hepatocyte-like cells, reducing inflammation, and enhancing tissue repair. Despite recent progress, exact mechanisms of action are not clearly elucidated. In this study, we attempted to explore whether and how MSCs protected hepatocytes and stimulated allograft regeneration in small-for-size liver transplantation (SFSLT. METHODS: SFSLT model was established with a 30% partial liver transplantation (30PLT in rats. The differentiation potential and characteristics of bone marrow derived MSCs were explored in vitro. MSCs were infused transvenously immediately after graft implantation in therapy group. Expressions of apoptosis-, inflammatory-, anti-inflammatory-, and growth factor-related genes were measured by RT-PCR, activities of transcription factors AP-1 and NF-κB were analyzed by EMSA, and proliferative responses of the hepatic graft were evaluated by immunohistochemistry and western blot. RESULTS: MSCs were successfully induced into hepatocyte-like cells, osteoblasts and adipocytes in vitro. MSCs therapy could not only alleviate ischemia reperfusion injury and acute inflammation to promote liver regeneration, but also profoundly improve one week survival rate. It markedly up-regulated the mRNA expressions of HGF, Bcl-2, Bcl-XL, IL-6, IL-10, IP-10, and CXCR2, however, down-regulated TNF-α. Increased activities of AP-1 and NF-κB, as well as elevated expressions of p-c-Jun, cyclin D1, and proliferating cell nuclear antigen (PCNA, were also found in MSCs therapy group. CONCLUSION: These data suggest that MSCs therapy promotes hepatocyte proliferation and prolongs survival in SFSLT by reducing ischemia reperfusion injury and acute inflammation, and sustaining early increased expressions of c-Jun N-terminal Kinase, Cyclin D1, and NF-κB.

  19. Preparation and Characteristics of Corn Straw-Co-AMPS-Co-AA Superabsorbent Hydrogel

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    Cheng, Wei-Min; Hu, Xiang-Ming; Wang, De-Ming; Liu, Guo-Hua

    2015-01-01

    In this study, the corn straw after removing the lignin was grafted with 2-acrylamido-2-methylpropanesulfonic acid (AMPS) to prepare sulfonated cellulose. The grafting copolymerization between the sulfonated cellulose and acrylic acid (AA) was performed using potassium persulfate and N,N′-methylenebisacrylamide as the initiator and crosslinking agent, respectively, to prepare corn straw-co-AMPS-co-AA hydrogels. The structure and properties of the resulting hydrogels were characterized by Four...

  20. A (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer)-dispersed sustained-release tablet for imperialine to simultaneously prolong the drug release and improve the oral bioavailability.

    Science.gov (United States)

    Lin, Qing; Fu, Yu; Li, Jia; Qu, Mengke; Deng, Li; Gong, Tao; Zhang, Zhirong

    2015-11-15

    Imperialine, extracted from Bulbus Fritillariae Cirrhosae, is an efficient antitussive and expectorant medicine. However, its short half-life and stomach degradation limited imperialine from further clinical use. The current study was conducted to develop a sustained-release tablet for imperialine both to prolong absorption time and to improve the oral bioavailability of the drug. The tablets were prepared by a direct compression method formulated on optimized solid dispersion (SD) for imperialine based on polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus(®)) with imperialine/Soluplus(®) ratio of 1:8 (w/w). In order to obtain the optimized formulation, factors that affected the drug release were investigated by in vitro dissolution studies in the media of pH1.2, 5.8, 7.0 and 7.4. Powder X-ray diffraction and scanning electron microscope confirmed that the imperialine in SD was amorphous instead of crystalline, and still stayed amorphous even after the direct compression. And besides, pharmacokinetic study in Beagle dogs was performed to inspect the in vivo sustained release. Plasma concentration-time curves and pharmacokinetic parameters were gained. As a result, the Cmax of imperialine was one-fold reduced and Tmax was two-fold prolonged, and the mean AUC0-24 was expressed as 89.581±21.243μgh/L, which showed that the oral bioavailability of imperialine was 2.46-fold improved. Moreover, the in vitro-in vivo correlation was recommended to carry out, demonstrating the percentages of drug release in vitro were well-correlated with the absorptive fraction in vivo with the correlation coefficients above 0.9900. By mathematically modeling and moment imaging of the drug release, Peppas equation was selected as the most fitted model for the sustained-release tablets with the diffusional coefficient in the range of 0.59-0.62, indicating the release of imperialine from the sustained-release tablets was an anomalous process involving

  1. Melting graft wound syndrome

    Directory of Open Access Journals (Sweden)

    Shiou-Mei Chen

    2017-09-01

    Full Text Available Melting graft wound syndrome is characterized by progressive epidermal loss from a previously well-taken skin graft, healed burn, or donor site. It may result in considerable morbidity and require prolonged treatment. We report a 23-year-old flame-burned patient with second- to third-degree burns involving more than 70% of the total body surface area, whose condition was complicated with septic shock. The patient presented with erosions and ulcers occurring on previously well-taken skin graft recipient sites over both legs and progressive epidermal loss on donor sites over the back. The patient's presentation was compatible with the diagnosis of melting graft wound syndrome, and we successfully treated the patient with debridement and supportive treatment.

  2. Assisted Medical Procedures (AMP)

    Data.gov (United States)

    National Aeronautics and Space Administration — DOCUMENTATION, DEVELOPMENT, AND PROGRESS The AMP was initially being developed as part the Advanced Integrated Clinical System (AICS)-Guided Medical Procedure System...

  3. Drug AMP Reporting - Quarterly

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drugs that have been reported under the Medicaid Drug Rebate Program along with an indication of whether or not the required Average Manufacturer Price (AMP) was...

  4. Antimicrobial Peptides (AMPs

    Directory of Open Access Journals (Sweden)

    Mehrzad Sadredinamin

    2016-04-01

    Full Text Available Antimicrobial peptides (AMPs are extensive group of molecules that produced by variety tissues of invertebrate, plants, and animal species which play an important role in their immunity response. AMPs have different classifications such as; biosynthetic machines, biological sources, biological functions, molecular properties, covalent bonding patterns, three dimensional structures, and molecular targets.These molecules have multidimensional properties including antimicrobial activity, antiviral activity, antifungal activity, anti-parasite activity, biofilm control, antitumor activity, mitogens activity and linking innate to adaptive immunity that making them promising agents for therapeutic drugs. In spite of this advantage of AMPs, their clinical developments have some limitation for commercial development. But some of AMPs are under clinical trials for the therapeutic purpose such as diabetic foot ulcers, different bacterial infections and tissue damage. In this review, we emphasized on the source, structure, multidimensional properties, limitation and therapeutic applications of various antimicrobial peptides.

  5. Synthesis and Characterization of Graft Copolymer of Dextran and 2-Acrylamido-2-methylpropane Sulphonic Acid

    Directory of Open Access Journals (Sweden)

    Venkanna Azmeera

    2012-01-01

    Full Text Available A novel biodegradable graft copolymer of dextran (Dx and 2-acrylamido-2-methyl-1-propane sulphonic acid (AMPS was synthesized by grafting poly-AMPS chains onto dextran backbone by free radical polymerization using ceric ammonium nitrate (CAN as an initiator. Different amounts of AMPS were used to synthesize four different grades of graft copolymers with different side chain lengths. These grafted polymers were characterized by elemental analysis, FTIR, 1HNMR, rheological technique, scanning electron microscopy (SEM, thermogravimetric analysis (TGA, and X-ray diffractometry (XRD. They exhibited efficient flocculation performance in kaolin suspension.

  6. Anticonvulsant effect of AMP by direct activation of adenosine A1 receptor.

    Science.gov (United States)

    Muzzi, Mirko; Coppi, Elisabetta; Pugliese, Anna Maria; Chiarugi, Alberto

    2013-12-01

    Purinergic neurotransmission mediated by adenosine (Ado) type 1 receptors (A1Rs) plays pivotal roles in negative modulation of epileptic seizures, and Ado is thought to be a key endogenous anticonvulsant. Recent evidence, however, indicates that AMP, the metabolic precursor of Ado, also activate A1Rs. Here, we evaluated the antiepileptic effects of AMP adopting in vitro and in vivo models of epilepsy. We report that AMP reversed the increase in population spike (PS) amplitude and the decrease in PS latency induced by a Mg(2+)-free extracellular solution in CA1 neurons of mouse hippocampal slices. The AMP effects were inhibited by the A1R antagonist DPCPX, but not prevented by inhibiting conversion of AMP into Ado, indicating that AMP inhibited per se sustained hippocampal excitatory neurotransmission by directly activating A1Rs. AMP also reduced seizure severity and mortality in a model of audiogenic convulsion. Of note, the anticonvulsant effects of AMP were potentiated by preventing its conversion into Ado and inhibited by DPCPX. When tested in a model of kainate-induced seizure, AMP prolonged latency of convulsions but had no effects on seizure severity and mortality. Data provide the first evidence that AMP is an endogenous anticonvulsant acting at A1Rs. © 2013.

  7. SALIVARY ANTIMICROBIAL PROTEIN RESPONSE TO PROLONGED RUNNING

    Directory of Open Access Journals (Sweden)

    Suzanne Schneider

    2013-01-01

    Full Text Available Prolonged exercise may compromise immunity through a reduction of salivary antimicrobial proteins (AMPs. Salivary IgA (IgA has been extensively studied, but little is known about the effect of acute, prolonged exercise on AMPs including lysozyme (Lys and lactoferrin (Lac. Objective: To determine the effect of a 50-km trail race on salivary cortisol (Cort, IgA, Lys, and Lac. Methods: 14 subjects: (6 females, 8 males completed a 50km ultramarathon. Saliva was collected pre, immediately after (post and 1.5 hrs post race ( 1.5. Results: Lac concentration was higher at 1.5 hrs post race compared to post exercise (p0.05. IgA concentration, secretion rate, and IgA/Osm were lower 1.5 hrs post compared to pre race (p<0.05. Cort concentration was higher at post compared to 1.5 (p<0.05, but was unaltered from pre race levels. Subjects finished in 7.81 ± 1.2 hrs. Saliva flow rate did not differ between time points. Saliva Osm increased at post (p<0.05 compared to pre race. Conclusions: The intensity could have been too low to alter Lys and Lac secretion rates and thus, may not be as sensitive as IgA to changes in response to prolonged running. Results expand our understanding of the mucosal immune system and may have implications for predicting illness after prolonged running.

  8. Transcriptional regulation by cyclic AMP.

    Science.gov (United States)

    Montminy, M

    1997-01-01

    A number of hormones and growth factors have been shown to stimulate target cells via second messenger pathways that in turn regulate the phosphorylation of specific nuclear factors. The second messenger cyclic AMP, for example, regulates a striking number of physiologic processes, including intermediary metabolism, cellular proliferation, and neuronal signaling, by altering basic patterns of gene expression. Our understanding of cyclic AMP signaling in the nucleus has expanded considerably over the past decade, owing in large part to the characterization of cyclic AMP-responsive promoter elements, transcription factors that bind them, and signal-dependent coactivators that mediate target gene induction. More importantly, these studies have revealed new insights into biological problems as diverse as biological clocks and long-term memory. The purpose of this review is to describe the components of the cyclic AMP response unit and to analyze how these components cooperate to induce target gene expression in response to hormonal stimulation.

  9. Assisted Medical Procedures (AMP) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Documentation and Development: The AMP was initially being developed as part the Advanced Integrated Clinical System (AICS)-Guided Medical Procedure System for the...

  10. Sustained signalling by PTH modulates IP3 accumulation and IP3 receptors through cyclic AMP junctions

    Science.gov (United States)

    Meena, Abha; Tovey, Stephen C.; Taylor, Colin W.

    2015-01-01

    ABSTRACT Parathyroid hormone (PTH) stimulates adenylyl cyclase through type 1 PTH receptors (PTH1R) and potentiates the Ca2+ signals evoked by carbachol, which stimulates formation of inositol 1,4,5-trisphosphate (IP3). We confirmed that in HEK cells expressing PTH1R, acute stimulation with PTH(1-34) potentiated carbachol-evoked Ca2+ release. This was mediated by locally delivered cyclic AMP (cAMP), but unaffected by inhibition of protein kinase A (PKA), exchange proteins activated by cAMP, cAMP phosphodiesterases (PDEs) or substantial inhibition of adenylyl cyclase. Sustained stimulation with PTH(1-34) causes internalization of PTH1R–adenylyl cyclase signalling complexes, but the consequences for delivery of cAMP to IP3R within cAMP signalling junctions are unknown. Here, we show that sustained stimulation with PTH(1-34) or with PTH analogues that do not evoke receptor internalization reduced the potentiated Ca2+ signals and attenuated carbachol-evoked increases in cytosolic IP3. Similar results were obtained after sustained stimulation with NKH477 to directly activate adenylyl cyclase, or with the membrane-permeant analogue of cAMP, 8-Br-cAMP. These responses were independent of PKA and unaffected by substantial inhibition of adenylyl cyclase. During prolonged stimulation with PTH(1-34), hyperactive cAMP signalling junctions, within which cAMP is delivered directly and at saturating concentrations to its targets, mediate sensitization of IP3R and a more slowly developing inhibition of IP3 accumulation. PMID:25431134

  11. Salbutamol delays human eosinophil apoptosis via a cAMP-dependent mechanism.

    Science.gov (United States)

    Kankaanranta, Hannu; Parkkonen, Jouni; Ilmarinen-Salo, Pinja; Giembycz, Mark A; Moilanen, Eeva

    2011-08-01

    Eosinophils play a major role in asthma. One described mechanism leading to the impaired clearance of these cells from the lung is the delay in their programmed cell death (apoptosis). β(2)-Adrenoceptor agonists have been shown to prolong survival and delay apoptosis of eosinophils. The aim of the present study was to evaluate the mechanisms, especially the role of cAMP pathway, in the prolongation of human eosinophil survival by a selective β(2)-agonist salbutamol. Isolated human peripheral blood eosinophils were cultured in the absence or presence of a β(2)-agonist salbutamol and the indicated antagonists/inhibitors under sterile conditions. Apoptosis was measured by using the relative DNA fragmentation assay and Annexin-V binding. Salbutamol prolonged survival of human eosinophils and it was inhibited by a β-receptor antagonist propranolol and mimicked by cell-permeant cAMP analogues dibutyryl- and 8-bromo-cAMP. Pharmacological inhibitors of adenylyl cyclase (SQ-22,536) and protein kinase A (Rp-8-CPT-cAMPS) antagonized the effects of salbutamol. The survival-prolonging action of salbutamol was potentiated by a phosphodiesterase inhibitor rolipram (EC(50) for the salbutamol effect was 13.6 ± 4.0 and 8.1 ± 3.1 nM in the absence and presence of rolipram, respectively; p=0.0142, n=10). In contrast, inhibition of Ca(2+)-activated K(+)-channels by apamin, charybdotoxin, iberiotoxin or paxilline did not affect the ability of salbutamol to prolong eosinophil survival. Taken together, the present results suggest that salbutamol at clinically relevant concentrations decreases apoptosis in human eosinophils by activating the cannonical β(2)-receptor-adenylyl cyclase-cAMP-protein kinase A pathway. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Ru (amp)(bipy)Cl

    Indian Academy of Sciences (India)

    Administrator

    [RuV(amp)(bipy)O]+ intermediate complex which leads to the high affinity for hydrogen atom/hydride abstraction. Acknowledgement. We gratefully acknowledge the financial support from the Department of Science &. Technology, Government of India. We are thankful to Shri Hardyal Singh for his encouragement. Reference.

  13. 3' : 5'-Cyclic AMP-dependent 3'

    NARCIS (Netherlands)

    Mato, José M.; Krens, Frans A.; Haastert, Peter J.M. van; Konijn, Theo M.

    1977-01-01

    Suspensions of 3':5'-cyclic AMP (cAMP)-sensitive cells of Dictyostelium discoideum responded to a cAMP pulse with increased 3':5'-cyclic GMP (cGMP) levels. Under the assay conditions used (2 × 10^8 cells per ml in 10 mM phosphate buffer, pH 6.0) cAMP (5 × 10-8 M final concentration) increased cGMP

  14. Improvement of polymer stability by radiation grafting

    International Nuclear Information System (INIS)

    Ranogajec, F.; Mlinac-Misak, M.

    1999-01-01

    Losses of the stabilizer due to extractability or volatility immediately affect ultimate performance of polymer product. A new approach to increase the persistence of the stabilizer in the final product is to chemically bind it to the polymer backbone. Radiation grafting or crosslinking could be an efficient method for this, when the stabilizer is polymerizable. By a mutual gamma irradiation method, photoprotector 2-hydroxy-4-(3-methacryloxy-2- hydroxy-propoxy) benzophenone (HMB) has been readily grafted to low density polyethylene (LDPE) in benzene, tetrahydrofuran and methanol solution, respectively. Surface grafting occurs in a methanol solution of stabilizer, while in benzene and tetrahydrofuran solutions of stabilizer, grafting proceeds more or less in the inner parts of the polymeric film as well. The grafted LDPE film in methanol and tetrahydrofuran (containing 1 w/w % of grafted HMB), 1 w/w % blended HMB with LDPE and nongrafted LDPE film, were all exposed to accelerated aging and natural weathering and their spectral changes, expressed by the carbonyl index, were then compared. The change of elongation at break and tensile strength were measured in the course of aging. UV stability tests on aged films and change in mechanical properties indicate a pronounced protective effect achieved by grafted stabilizer. Grafting in methanol solution appears to be an efficient photostabilization treatment and the most economical with respect to the consumption of monomer, the grafting yield being less than 0.5%. Surface grafting is an efficient photostabilization method since grafted stabilizer is chemically bound to a polymeric surface and in this way the problem of evaporation of blended stabilizers during the prolonged use of polymeric materials is eliminated. (author)

  15. Pseudomonas aeruginosa β-lactamase induction requires two permeases, AmpG and AmpP

    Directory of Open Access Journals (Sweden)

    Schneper Lisa

    2010-12-01

    Full Text Available Abstract Background In Enterobacteriaceae, β-lactam antibiotic resistance involves murein recycling intermediates. Murein recycling is a complex process with discrete steps taking place in the periplasm and the cytoplasm. The AmpG permease is critical to this process as it transports N-acetylglucosamine anhydrous N-acetylmuramyl peptides across the inner membrane. In Pseudomonadaceae, this intrinsic mechanism remains to be elucidated. Since the mechanism involves two cellular compartments, the characterization of transporters is crucial to establish the link. Results Pseudomonas aeruginosa PAO1 has two ampG paralogs, PA4218 (ampP and PA4393 (ampG. Topology analysis using β-galactosidase and alkaline phosphatase fusions indicates ampP and ampG encode proteins which possess 10 and 14 transmembrane helices, respectively, that could potentially transport substrates. Both ampP and ampG are required for maximum expression of β-lactamase, but complementation and kinetic experiments suggest they act independently to play different roles. Mutation of ampG affects resistance to a subset of β-lactam antibiotics. Low-levels of β-lactamase induction occur independently of either ampP or ampG. Both ampG and ampP are the second members of two independent two-gene operons. Analysis of the ampG and ampP operon expression using β-galactosidase transcriptional fusions showed that in PAO1, ampG operon expression is β-lactam and ampR-independent, while ampP operon expression is β-lactam and ampR-dependent. β-lactam-dependent expression of the ampP operon and independent expression of the ampG operon is also dependent upon ampP. Conclusions In P. aeruginosa, β-lactamase induction occurs in at least three ways, induction at low β-lactam concentrations by an as yet uncharacterized pathway, at intermediate concentrations by an ampP and ampG dependent pathway, and at high concentrations where although both ampP and ampG play a role, ampG may be of greater

  16. In Vivo Cardiovascular Pharmacology of 2′,3′-cAMP, 2′-AMP, and 3′-AMP in the Rat

    Science.gov (United States)

    Mi, Zaichuan

    2013-01-01

    The naturally occurring purine 2′,3′-cAMP is metabolized in vitro to 2′-AMP and 3′-AMP, which are subsequently metabolized to adenosine. Whether in vivo 2′,3′-cAMP, 2′-AMP, or 3′-AMP are rapidly converted to adenosine and exert rapid effects via adenosine receptors is unknown. To address this question, we compared the cardiovascular and renal effects of 2′,3′-cAMP, 2′-AMP, 3′-AMP, 3′,5′-cAMP, 5′-AMP, and adenosine in vivo in the rat. Purines were infused intravenously while monitoring mean arterial blood pressure (MABP), heart rate (HR), cardiac output, and renal and mesenteric blood flows. Total peripheral (TPR), renal vascular (RVR), and mesenteric vascular (MVR) resistances were calculated. Urine was collected for determination of urine excretion rate [urine volume (UV)]. When sufficient urine was available, the sodium excretion rate (Na+ER) and glomerular filtration rate (GFR) were determined. 2′,3′-cAMP, 2′-AMP, and 3′-AMP dose-dependently and profoundly reduced MABP, HR, TPR, and MVR with efficacy and potency similar to adenosine and 5′-AMP. These effects of 2′,3′-cAMP, 2′-AMP, and 3′-AMP were attenuated by blockade of adenosine receptors with 1,3-dipropyl-8-(p-sulfophenyl)xanthine. 2′,3′-cAMP, 2′-AMP, 3′-AMP, adenosine, and 5′-AMP variably affected RVR, but profoundly (nearly 100%) decreased UV at higher doses. GFR and Na+ER could be measured at the lower doses and were suppressed by 2′,3′-cAMP, 2′-AMP, and 3′-AMP, but not by adenosine or 5′-AMP. 2′,3′-cAMP increased urinary excretion rates of 2′-AMP, 3′-AMP, and adenosine. 3′,5′-cAMP exerted no adverse hemodynamic effects yet increased urinary adenosine as efficiently as 2′,3′-cAMP. Conclusions: In vivo 2′,3′-cAMP is rapidly converted to adenosine. Because both cAMPs increase adenosine in the urinary compartment, these agents may provide unique therapeutic opportunities. PMID:23759508

  17. Exhaustion from prolonged gambling

    Directory of Open Access Journals (Sweden)

    Fatimah Lateef

    2013-01-01

    Full Text Available Complaints of fatigue and physical exhaustion are frequently seen in the acute medical setting, especially amongst athletes, army recruits and persons involved in strenuous and exertional physical activities. Stress-induced exhaustion, on the other hand, is less often seen, but can present with very similar symptoms to physical exhaustion. Recently, three patients were seen at the Department of Emergency Medicine, presenting with exhaustion from prolonged involvement in gambling activities. The cases serve to highlight some of the physical consequences of prolonged gambling.

  18. Bifunctional groups grafted polyethersulfone magnetic beads for selective sequestration of plutonium

    International Nuclear Information System (INIS)

    Paul, Sumana; Aggarwal, S.K.; Pandey, A.K.

    2014-01-01

    The present study involves synthesis of polyethersulfone (PES) beads grafted with two different monomers viz. 2-hydroxyethylmethacrylate phosphoric acid ester (HEMP) and 2-acrylamido-2-methyl-1-propane sulphonic acid (AMPS) by photo-induced free radical polymerization method. The selection of bifunctional polymer was based on our previous studies, which indicated its efficacy for selective preconcentration of Pu from 3-4 mol L -1 HNO 3 . The HEMP-co-AMPS grafted PES beads were used for selective extraction of plutonium from dissolver solution

  19. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  20. Significant prolongation of hamster liver transplant survival in Lewis rats by total-lymphoid irradiation, cyclosporine, and splenectomy

    International Nuclear Information System (INIS)

    Yamaguchi, Y.; Halperin, E.C.; Harland, R.C.; Wyble, C.; Bollinger, R.R.

    1990-01-01

    The effects of total lymphoid irradiation, cyclosporine and splenectomy alone and in combination have been studied in liver transplants from the LVG hamster to the LEW rat. Neither CsA alone, splenectomy alone, nor TLI alone prolonged graft survival. CsA/splenectomy and TLI/CsA produced significant prolongation of graft survival. TLI/CsA/splenectomy prolonged graft survival by over sixfold compared with controls. While CsA alone was ineffective in reducing lymphocytotoxic antidonor antibody, splenectomy alone or CsA/splenectomy did significantly suppress production of antibody. Only very low levels of antibody could be detected in animals treated with TLI/CsA/splenectomy. TLI/CsA/splenectomy has an immunosuppressive effect sufficient to significantly prolong liver graft survival in the LVG hamster to LEW rat combination and may represent a promising treatment protocol in experimental cross-species transplantation

  1. Cartilage grafting in facial reconstruction with special consideration of irradiated grafts

    International Nuclear Information System (INIS)

    Donald, P.J.

    1986-01-01

    The search for the perfect facial implant for reconstruction of the face continues. Cartilage, once thought to be an undesirable graft material because of its propensity for absorption, has regained popularity in the past decade. Various preparation techniques have been employed to ensure graft sterility and diminished absorption. An improved understanding of cartilage structure and physiology has shed considerable light on the host-graft relationship. Gamma irradiation is a time-honored method of preservation. An experiment was undertaken to investigate the physiology of irradiated cartilage grafts following prolonged implantation on the facial skeleton of sheep and dog. Merthiolate preserved grafts were used as controls. Direct observation, histochemical techniques, autoradiography, and transmission electron micrography were used to determine chondrocyte viability and matrix composition. It was surprising to note that following implantation of 16 to 72 months, complete resorption was seen in 87.7% of the irradiated grafts and in 43.8% of the Merthiolate stored controls. Many of the grafts acquired chondrocytes from the host and produced new proteoglycan matrix as well as undergoing some degree of ossification. A comparison to the clinical situation in humans is made. 98 references

  2. Release from Xenopus oocyte prophase I meiotic arrest is independent of a decrease in cAMP levels or PKA activity.

    Science.gov (United States)

    Nader, Nancy; Courjaret, Raphael; Dib, Maya; Kulkarni, Rashmi P; Machaca, Khaled

    2016-06-01

    Vertebrate oocytes arrest at prophase of meiosis I as a result of high levels of cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) activity. In Xenopus, progesterone is believed to release meiotic arrest by inhibiting adenylate cyclase, lowering cAMP levels and repressing PKA. However, the exact timing and extent of the cAMP decrease is unclear, with conflicting reports in the literature. Using various in vivo reporters for cAMP and PKA at the single-cell level in real time, we fail to detect any significant changes in cAMP or PKA in response to progesterone. More interestingly, there was no correlation between the levels of PKA inhibition and the release of meiotic arrest. Furthermore, we devised conditions whereby meiotic arrest could be released in the presence of sustained high levels of cAMP. Consistently, lowering endogenous cAMP levels by >65% for prolonged time periods failed to induce spontaneous maturation. These results argue that the release of oocyte meiotic arrest in Xenopus is independent of a reduction in either cAMP levels or PKA activity, but rather proceeds through a parallel cAMP/PKA-independent pathway. © 2016. Published by The Company of Biologists Ltd.

  3. Antimicrobials and QT prolongation.

    Science.gov (United States)

    Mason, Jay W

    2017-05-01

    Solithromycin, a ketolide/macrolide antibiotic, has recently been reported to be free of the expected QT-prolonging effect of macrolides. It appears that its keto substitution provides a structural basis for this observation, as the other two tested ketolides also have minimal QT effect.Among non-cardiovascular therapies, antimicrobials probably carry the greatest potential to cause cardiac arrhythmias. This is a result of their propensity to bind to the delayed rectifier potassium channel, IKr, inducing QT prolongation and risk of torsades de pointes ventricular tachycardia, their frequent interference with the metabolism of other QT prolongers and their susceptibility to metabolic inhibition by numerous commonly used drugs.Unfortunately, there is evidence that medical practitioners do not take account of the QT/arrhythmia risk of antimicrobials in their prescribing practices. Education on this topic is sorely needed. When a macrolide is indicated, a ketolide should be considered in patients with a QT risk. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Grafting and curing

    International Nuclear Information System (INIS)

    Garnett, J.L.; Loo-Teck Ng; Visay Viengkhou

    1998-01-01

    Progress in radiation grafting and curing is briefly reviewed. The two processes are shown to be mechanistically related. The parameters influencing yields are examined particularly for grafting. For ionising radiation grafting systems (EB and gamma ray) these include solvents, substrate and monomer structure, dose and dose-rate, temperature and more recently role of additives. In addition, for UV grafting, the significance of photoinitiators is discussed. Current applications of radiation grafting and curing are outlined. The recent development of photoinitiator free grafting and curing is examined as well as the potential for the new excimer laser sources. The future application of both grafting and curing is considered, especially the significance of the occurrence of concurrent grafting during cure and its relevance in environmental considerations

  5. Preparation and Characteristics of Corn Straw-Co-AMPS-Co-AA Superabsorbent Hydrogel

    Directory of Open Access Journals (Sweden)

    Wei-Min Cheng

    2015-11-01

    Full Text Available In this study, the corn straw after removing the lignin was grafted with 2-acrylamido-2-methylpropanesulfonic acid (AMPS to prepare sulfonated cellulose. The grafting copolymerization between the sulfonated cellulose and acrylic acid (AA was performed using potassium persulfate and N,N′-methylenebisacrylamide as the initiator and crosslinking agent, respectively, to prepare corn straw-co-AMPS-co-AA hydrogels. The structure and properties of the resulting hydrogels were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and dynamic rheometry. The effects of initiator, crosslinker, monomer neutralization degree, and temperature on the swelling ratio of the hydrogels were studied. The water retention, salt resistance, and recyclability of the corn straw-co-AMPS-co-AA hydrogels were also investigated. The optimum water absorptivity of the corn straw hydrogels was obtained at a polymerization temperature of 50 °C with 1.2% crosslinker, 1:7 ratio of the pretreated corn straw and AA, 2% initiator, and 50% neutralized AA.

  6. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  7. cAMP signaling in subcellular compartments.

    Science.gov (United States)

    Lefkimmiatis, Konstantinos; Zaccolo, Manuela

    2014-09-01

    In the complex microcosm of a cell, information security and its faithful transmission are critical for maintaining internal stability. To achieve a coordinated response of all its parts to any stimulus the cell must protect the information received from potentially confounding signals. Physical segregation of the information transmission chain ensures that only the entities able to perform the encoded task have access to the relevant information. The cAMP intracellular signaling pathway is an important system for signal transmission responsible for the ancestral 'flight or fight' response and involved in the control of critical functions including frequency and strength of heart contraction, energy metabolism and gene transcription. It is becoming increasingly apparent that the cAMP signaling pathway uses compartmentalization as a strategy for coordinating the large number of key cellular functions under its control. Spatial confinement allows the formation of cAMP signaling "hot spots" at discrete subcellular domains in response to specific stimuli, bringing the information in proximity to the relevant effectors and their recipients, thus achieving specificity of action. In this report we discuss how the different constituents of the cAMP pathway are targeted and participate in the formation of cAMP compartmentalized signaling events. We illustrate a few examples of localized cAMP signaling, with a particular focus on the nucleus, the sarcoplasmic reticulum and the mitochondria. Finally, we discuss the therapeutic potential of interventions designed to perturb specific cAMP cascades locally. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Schwann Cells Metabolize Extracellular 2′,3′-cAMP to 2′-AMP

    Science.gov (United States)

    Verrier, Jonathan D.; Kochanek, Patrick M.

    2015-01-01

    The 3′,5′-cAMP–adenosine pathway (3′,5′-cAMP→5′-AMP→adenosine) and the 2′,3′-cAMP–adenosine pathway (2′,3′-cAMP→2′-AMP/3′-AMP→adenosine) are active in the brain. Oligodendrocytes participate in the brain 2′,3′-cAMP–adenosine pathway via their robust expression of 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNPase; converts 2′,3′-cAMP to 2′-AMP). Because Schwann cells also express CNPase, it is conceivable that the 2′,3′-cAMP–adenosine pathway exists in the peripheral nervous system. To test this and to compare the 2′,3′-cAMP–adenosine pathway to the 3′,5′-cAMP–adenosine pathway in Schwann cells, we examined the metabolism of 2′,3′-cAMP, 2′-AMP, 3′-AMP, 3′,5′-cAMP, and 5′-AMP in primary rat Schwann cells in culture. Addition of 2′,3′-cAMP (3, 10, and 30 µM) to Schwann cells increased levels of 2′-AMP in the medium from 0.006 ± 0.002 to 21 ± 2, 70 ± 3, and 187 ± 10 nM/µg protein, respectively; in contrast, Schwann cells had little ability to convert 2′,3′-cAMP to 3′-AMP or 3′,5′-cAMP to either 3′-AMP or 5′-AMP. Although Schwann cells slightly converted 2′,3′-cAMP and 2′-AMP to adenosine, they did so at very modest rates (e.g., 5- and 3-fold, respectively, more slowly compared with our previously reported studies in oligodendrocytes). Using transected myelinated rat sciatic nerves in culture medium, we observed a time-related increase in endogenous intracellular 2′,3′-cAMP and extracellular 2′-AMP. These findings indicate that Schwann cells do not have a robust 3′,5′-cAMP–adenosine pathway but do have a 2′,3′-cAMP–adenosine pathway; however, because the pathway mostly involves 2′-AMP formation rather than 3′-AMP, and because the conversion of 2′-AMP to adenosine is slow, metabolism of 2′,3′-cAMP mostly results in the accumulation of 2′-AMP. Accumulation of 2′-AMP in peripheral nerves postinjury could have

  9. Intrusion Detection amp Prevention Systems - Sourcefire Snort

    Directory of Open Access Journals (Sweden)

    Rajesh Vuppala

    2015-08-01

    Full Text Available Information security is a challenging issue for all business organizations today amidst increasing cyber threats. While there are many alternative intrusion detection amp prevention systems available to choose from selecting the best solution to implement to detect amp prevent cyber-attacks is a difficult task. The best solution is of the one that gets the best reviews and suits the organizations needs amp budget. In this review paper we summarize various classes of intrusion detection and prevention systems compare features of alternative solutions and make recommendation for implementation of one as the best solution for business organization in Fiji.

  10. Management of prolonged pregnancy

    International Nuclear Information System (INIS)

    Iqbal, S.

    2004-01-01

    Objective: To compare two strategies for management of prolonged pregnancy (= or >294 days) i.e. induction (intervention) versus expectant management (non-intervention) and evaluate the associated feto-maternal risks. Subjects and Methods: One hundred cases of uncomplicated prolonged gestation were selected. The gestational age was confirmed by ultrasound in first trimester. One group (50 patients) was managed by intervention i.e. induction of labour (group A) and other group (50 patients) by non-intervention i.e. expectant management (group B). In group A intervention was done at 42 weeks. In expectant group, the methods of monitoring were fetal kick charting recorded daily by the patient, and ultrasound for amniotic fluid index. The biophysical profile score and NST (non stress test) were performed once a week till 42 weeks and then twice weekly. Results: The frequency of prolonged pregnancy was found to be 10.9%. There was no significant difference in the number of spontaneous vaginal deliveries between the two groups. The rate of LSCS (lower segment caesarean section) was higher in intervention group ( 30% versus 18% ). The neonatal depression at birth was more in group B ( 10% versus 4%) and at 5 minutes almost same between two groups (4% versus 2%). There were 11 cases of meconium aspiration syndrome, leading to one neonatal death. Among nine perinatal deaths two were neonatal deaths. Seven cases of intrauterine deaths in which antepartum deaths occurred because of non compliance of patients. No cause could be detected for the other three fetuses. Conclusion: There was increased LSCS rate in group A. However in expectant group B perinatal mortality was about twice more as compared to intervention group. Active early intervention at 42 weeks is warranted to reduce perinatal morbidity and mortality. (author)

  11. Warmer amps for the LHC

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    CERN is working together with an Italian company to develop superconducting cables that can function at temperatures of up to 25 K (-248°C). This will make it possible to move LHC magnet power supplies out of the tunnel, protecting them from exposure to the showers of very high-energy particles produced by the accelerator.   Figure 1: devices of this type, which measure approximately 10 metres in length, are inserted between the accelerating magnets at different points along the LHC. When it comes to consuming electricity, the magnets that steer particles through large accelerators can be characterised with just one word: greedy. For the LHC, the total current can reach 1.5 million amps. At the present time, this current is brought in via copper cables of up to 10 cm in diameter. In the tunnel, these cables connect the current leads - which provide the transition between the ambient-temperature cables and the magnets in their bath of superfluid helium - to the power supply. In the a...

  12. Thioredoxin priming prolongs lung allograft survival by promoting immune tolerance.

    Science.gov (United States)

    Hu, Hanbo; Zhu, Xiaoyan; Joshi, Sunil; Lu, Li; Xia, Chang-Qing; Patel, Jawaharlal M

    2015-01-01

    Tolerance to allograft antigen is the major challenge and final goal of transplant medicine. Our previous study demonstrated that thioredoxin-1 (Trx) priming of donor lung significantly protected allogeneic lung graft. To determine whether Trx priming of donor lung inhibits allograft rejection, extends allograft survival and induces immune tolerance, orthotopic left lung transplantation was performed from Lewis to Sprague-Dawley rats without immunosuppression. Donor lungs were primed with Trx at 4°C for 4 hr prior to transplantation. After up to 37 days post-transplantation, allograft lung morphology, recipient T cell and humoral alloantigen-specific immune responses were examined. We found that Trx-primed lungs exhibited much reduced acute rejection and associated lung injuries resulting in loss of graft functional area at 5-37 days post-transplant in contrast to the control groups. CD4+ T cells from the recipients with Trx-primed grafts responded to the stimulation of dendritic cells (DCs) of donor origin, in contrast to DCs from the third party, with significantly reduced proliferation. Consistent with above findings, we observed that CD4+Foxp3+ regulatory T cells in spleen cells from the recipients with Trx-primed grafts were significantly increased compared to controls, and CD4+ T cells from the recipients with Trx-primed grafts produced much higher levels of immunosuppressive cytokine, IL-10 when stimulated with allogeneic donor DCs. In addition, humoral immune tolerance was also induced as there was no significant increase levels of serum antibodies against donor antigens in Trx-lung recipients when re-challenged with allogeneic donor antigens. Our results demonstrate that one-time Trx-priming of donor lung grafts prior to transplantation significantly prolongs the survival of the grafts through inducing or promoting cellular and humoral alloantigen-specific immune tolerance, which might be associated with the induction of immunosuppressive regulatory T

  13. Thioredoxin priming prolongs lung allograft survival by promoting immune tolerance.

    Directory of Open Access Journals (Sweden)

    Hanbo Hu

    Full Text Available Tolerance to allograft antigen is the major challenge and final goal of transplant medicine. Our previous study demonstrated that thioredoxin-1 (Trx priming of donor lung significantly protected allogeneic lung graft. To determine whether Trx priming of donor lung inhibits allograft rejection, extends allograft survival and induces immune tolerance, orthotopic left lung transplantation was performed from Lewis to Sprague-Dawley rats without immunosuppression. Donor lungs were primed with Trx at 4°C for 4 hr prior to transplantation. After up to 37 days post-transplantation, allograft lung morphology, recipient T cell and humoral alloantigen-specific immune responses were examined. We found that Trx-primed lungs exhibited much reduced acute rejection and associated lung injuries resulting in loss of graft functional area at 5-37 days post-transplant in contrast to the control groups. CD4+ T cells from the recipients with Trx-primed grafts responded to the stimulation of dendritic cells (DCs of donor origin, in contrast to DCs from the third party, with significantly reduced proliferation. Consistent with above findings, we observed that CD4+Foxp3+ regulatory T cells in spleen cells from the recipients with Trx-primed grafts were significantly increased compared to controls, and CD4+ T cells from the recipients with Trx-primed grafts produced much higher levels of immunosuppressive cytokine, IL-10 when stimulated with allogeneic donor DCs. In addition, humoral immune tolerance was also induced as there was no significant increase levels of serum antibodies against donor antigens in Trx-lung recipients when re-challenged with allogeneic donor antigens. Our results demonstrate that one-time Trx-priming of donor lung grafts prior to transplantation significantly prolongs the survival of the grafts through inducing or promoting cellular and humoral alloantigen-specific immune tolerance, which might be associated with the induction of

  14. Radial nerve grafting in high energy humeral fractures

    Directory of Open Access Journals (Sweden)

    Yusuf Gurbuz

    2012-08-01

    Conclusion: Prolonged external fixation and extensive crush arm injuries can decrease the success of nerve healing. Excluding these conditions, good functional results may be obtained with nerve grafts longer than eight cm associated with high energy humeral fractures. [Hand Microsurg 2012; 1(2.000: 60-64

  15. Preparation of metal ion exchange resin by radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Nakase, Yoshiaki; Akasaka, Nobuhiro.

    1982-06-01

    Radiation-induced graft copolymerization of 2-acrylamide-2-methyl propane sulfonic acid (AMPS) onto polyvinylchloride (PVC) and polyvinylidene chloride resin (PVD) was investigated in the water-acetone system and their adsorptive activities to metal ion were also examined. In the case of PVC, the degree of grafting increased with the increase of acetone content, but the adsorptive activity to metal ions (mainly lithic ion) became maximum in the system with water/acetone of 2/3. Grafted PVC prepared at about 35 0 C and at a higher concentration of AMPS showed higher adsorption activity than the other cases. In the case of PVD, a similar result was obtained with the case of PVC except the temperature dependence and effect of swelling agent. Polymerizations at temperatures of 35 and 50 0 C showed no effect on the degree of grafting, and the usage of a swelling agent was quite effective to the adsorptive activity. Glass transition temperature of the grafted copolymer was the same as that of original polymer, and their thermal stability was confirmed up to the temperature at which homopolymer of AMPS decomposed, about 180 0 C. (author)

  16. Interaction of biodegradative threonine dehydratase (TD) of Escherichia coli with 8-azido-AMP, a photoaffinity analog of AMP

    International Nuclear Information System (INIS)

    Patil, R.V.; Datta, P.

    1987-01-01

    Stimulation of TD activity by AMP (Ka = 40 μM) is known to accompany the conversion of monomeric form of the enzyme to its tetramer and a decrease in the Km for threonine. In comparison, 8-azido-AMP (N 3 AMP) simulated TD activity only partially, lowered the Km for threonine and stabilized a dimeric form of the protein. Competition experiments revealed that N 3 AMP exerted an apparent dominant effect in counteracting the AMP-mediated enzyme activation, indicating complex mutual interactions between these ligands. UV irradiation of TD with increasing concentrations of 3 H-N 3 AMP (up to 150 μM) resulted in gradual loss of enzyme activity and concomitant incorporation of N 3 AMP into protein; upon complete inactivation, 0.75 mol of N 3 AMP was bound per mol tetramer. The presence of AMP during photolysis reduced the extent of enzyme inactivation as well as the incorporation of N 3 AMP into protein. Photolabeling of TD with 20 μM 3 H-N 3 AMP revealed one labeled tryptic peptide; at higher N 3 AMP concentrations (>300 μM), two labeled peptides were found, one of which was identical to that found with low N 3 AMP concentration. The cumulative results suggest that N 3 AMP can act as an allosteric modifier and that the peptide labeled at low N 3 AMP may represent the AMP binding site on the protein molecule

  17. Aspirin decreases platelet uptake on Dacron vascular grafts in baboons

    International Nuclear Information System (INIS)

    Mackey, W.C.; Connolly, R.J.; Callow, A.D.

    1984-01-01

    The influence of a single dose of aspirin (5.4-7.4 mg/kg) on platelet uptake on 4-mm Dacron interposition grafts was studied in a baboon model using gamma camera scanning for 111-Indium labeled platelets. In vitro assessment of platelet function after aspirin administration revealed that in the baboon, as in the human, aspirin abolished arachidonic acid-induced platelet aggregation, prolonged the lag time between exposure to collagen and aggregation, and decreased plasma thromboxane B2 levels. Aspirin also prolonged the template bleeding time. Scans for 111-Indium labeled platelets revealed that pretreatment with a single dose of aspirin decreased platelet uptake on 4-mm Dacron carotid interposition grafts. This decrease in platelet uptake was associated with a significant improvement in 2-hour graft patency and with a trend toward improved 2-week patency

  18. Engineered vascularized bone grafts

    OpenAIRE

    Tsigkou, Olga; Pomerantseva, Irina; Spencer, Joel A.; Redondo, Patricia A.; Hart, Alison R.; O’Doherty, Elisabeth; Lin, Yunfeng; Friedrich, Claudia C.; Daheron, Laurence; Lin, Charles P.; Sundback, Cathryn A.; Vacanti, Joseph P.; Neville, Craig

    2010-01-01

    Clinical protocols utilize bone marrow to seed synthetic and decellularized allogeneic bone grafts for enhancement of scaffold remodeling and fusion. Marrow-derived cytokines induce host neovascularization at the graft surface, but hypoxic conditions cause cell death at the core. Addition of cellular components that generate an extensive primitive plexus-like vascular network that would perfuse the entire scaffold upon anastomosis could potentially yield significantly higher-quality grafts. W...

  19. The Hippo pathway mediates inhibition of vascular smooth muscle cell proliferation by cAMP.

    Science.gov (United States)

    Kimura, Tomomi E; Duggirala, Aparna; Smith, Madeleine C; White, Stephen; Sala-Newby, Graciela B; Newby, Andrew C; Bond, Mark

    2016-01-01

    Inhibition of vascular smooth muscle cell (VSMC) proliferation by intracellular cAMP prevents excessive neointima formation and hence angioplasty restenosis and vein-graft failure. These protective effects are mediated via actin-cytoskeleton remodelling and subsequent regulation of gene expression by mechanisms that are incompletely understood. Here we investigated the role of components of the growth-regulatory Hippo pathway, specifically the transcription factor TEAD and its co-factors YAP and TAZ in VSMC. Elevation of cAMP using forskolin, dibutyryl-cAMP or the physiological agonists, Cicaprost or adenosine, significantly increased phosphorylation and nuclear export YAP and TAZ and inhibited TEAD-luciferase report gene activity. Similar effects were obtained by inhibiting RhoA activity with C3-transferase, its downstream kinase, ROCK, with Y27632, or actin-polymerisation with Latrunculin-B. Conversely, expression of constitutively-active RhoA reversed the inhibitory effects of forskolin on TEAD-luciferase. Forskolin significantly inhibited the mRNA expression of the pro-mitogenic genes, CCN1, CTGF, c-MYC and TGFB2 and this was reversed by expression of constitutively-active YAP or TAZ phospho-mutants. Inhibition of YAP and TAZ function with RNAi or Verteporfin significantly reduced VSMC proliferation. Furthermore, the anti-mitogenic effects of forskolin were reversed by overexpression of constitutively-active YAP or TAZ. Taken together, these data demonstrate that cAMP-induced actin-cytoskeleton remodelling inhibits YAP/TAZ-TEAD dependent expression of pro-mitogenic genes in VSMC. This mechanism contributes novel insight into the anti-mitogenic effects of cAMP in VSMC and suggests a new target for intervention. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Down-regulation of Cell Surface Cyclic AMP Receptors and Desensitization of Cyclic AMP-stimulated Adenylate Cyclase by Cyclic AMP in Dictyostelium discoideum. Kinetics and Concentration Dependence

    NARCIS (Netherlands)

    Haastert, Peter J.M. van

    1987-01-01

    cAMP binds to Dictyostelium discoideum surface receptors and induces a transient activation of adenylate cyclase, which is followed by desensitization. cAMP also induces a loss of detectable surface receptors (down-regulation). Cells were incubated with constant cAMP concentrations, washed free of

  1. Purification, characterization, and sequencing of antimicrobial peptides, Cy-AMP1, Cy-AMP2, and Cy-AMP3, from the Cycad (Cycas revoluta) seeds.

    Science.gov (United States)

    Yokoyama, Seiya; Kato, Kouji; Koba, Atsuko; Minami, Yuji; Watanabe, Keiichi; Yagi, Fumio

    2008-12-01

    Novel antimicrobial peptides (AMP), designated Cy-AMP1, Cy-AMP2, and Cy-AMP3, were purified from seeds of the cycad (Cycas revoluta) by a CM cellulofine column, ion-exchange HPLC on SP COSMOGEL, and reverse-phase HPLC. They had molecular masses of 4583.2 Da, 4568.9 Da and 9275.8 Da, respectively, by MALDI-TOF MS analysis. Half of the amino acid residues of Cy-AMP1 and Cy-AMP2 were cysteine, glycine and proline, and their sequences were similar. The sequence of Cy-AMP3 showed high homology to various lipid transfer proteins. For Cy-AMP1 and Cy-AMP2, the concentrations of peptides required for 50% inhibition (IC(50)) of the growth of plant pathogenic fungi, Gram-positive and Gram-negative bacteria were 7.0-8.9 microg/ml. The Cy-AMP3 had weak antimicrobial activity. The structural and antimicrobial characteristics of Cy-AMP1 and Cy-AMP2 indicated that they are a novel type of antimicrobial peptide belonging to a plant defensin family.

  2. Osseous scintigraphy and auxiliary graft

    International Nuclear Information System (INIS)

    Khelifa, F.; Siles, S.; Puech, B.

    1992-01-01

    The scintigraphy could be a good way to survey the osseous graft: three cases are studied in which were recognized the presence of a graft, surinfection, graft lysis, pseudo-arthrosis, algodystrophy. 8 refs., 5 figs

  3. Meniscal allograft transplantation. Part 1: systematic review of graft biology, graft shrinkage, graft extrusion, graft sizing, and graft fixation.

    Science.gov (United States)

    Samitier, Gonzalo; Alentorn-Geli, Eduard; Taylor, Dean C; Rill, Brian; Lock, Terrence; Moutzouros, Vasilius; Kolowich, Patricia

    2015-01-01

    To provide a systematic review of the literature regarding five topics in meniscal allograft transplantation: graft biology, shrinkage, extrusion, sizing, and fixation. A systematic literature search was conducted using the PubMed (MEDLINE), ScienceDirect, and EBSCO-CINAHL databases. Articles were classified only in one topic, but information contained could be reported into other topics. Information was classified according to type of study (animal, in vitro human, and in vivo human) and level of evidence (for in vivo human studies). Sixty-two studies were finally included: 30 biology, 3 graft shrinkage, 11 graft extrusion, 17 graft size, and 6 graft fixation (some studies were categorized in more than one topic). These studies corresponded to 22 animal studies, 22 in vitro human studies, and 23 in vivo human studies (7 level II, 10 level III, and 6 level IV). The principal conclusions were as follows: (a) Donor cells decrease after MAT and grafts are repopulated with host cells form synovium; (b) graft preservation alters collagen network (deep freezing) and causes cell apoptosis with loss of viable cells (cryopreservation); (c) graft shrinkage occurs mainly in lyophilized and gamma-irradiated grafts (less with cryopreservation); (d) graft extrusion is common but has no clinical/functional implications; (e) overall, MRI is not superior to plain radiograph for graft sizing; (f) graft width size matching is more important than length size matching; (g) height appears to be the most important factor influencing meniscal size; (h) bone fixation better restores contact mechanics than suture fixation, but there are no differences for pullout strength or functional results; and (i) suture fixation has more risk of graft extrusion compared to bone fixation. Systematic review of level II-IV studies, Level IV.

  4. Advances in radiation grafting

    International Nuclear Information System (INIS)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H.A.; Kamal, H.; Kandeel, K.A.

    2001-01-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed

  5. Calcar bone graft

    Energy Technology Data Exchange (ETDEWEB)

    Bargar, W.L.; Paul, H.A.; Merritt, K.; Sharkey, N.

    1986-01-01

    A canine model was developed to investigate the use of an autogeneic iliac bone graft to treat the calcar deficiency commonly found at the time of revision surgery for femoral component loosening. Five large male mixed-breed dogs had bilateral total hip arthroplasty staged at three-month intervals, and were sacrificed at six months. Prior to cementing the femoral component, an experimental calcar defect was made, and a bicortical iliac bone graft was fashioned to fill the defect. Serial roentgenograms showed the grafts had united with no resorption. Technetium-99 bone scans showed more uptake at three months than at six months in the graft region. Disulfine blue injection indicated all grafts were perfused at both three and six months. Thin section histology, fluorochromes, and microradiographs confirmed graft viability in all dogs. Semiquantitative grading of the fluorochromes indicated new bone deposition in 20%-50% of each graft at three months and 50%-80% at six months. Although the calcar bone graft was uniformly successful in this canine study, the clinical application of this technique should be evaluated by long-term results in humans.

  6. Advances in radiation grafting

    Science.gov (United States)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H. A.; Kamal, H.; Kandeel, K. A.

    2001-12-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed.

  7. Transit Time Flowmetry in Coronary Surgery-An Important Tool in Graft Verification

    Directory of Open Access Journals (Sweden)

    Emir Mujanović

    2007-08-01

    Full Text Available The aim of this study was to analyze the Transit time flow measurement (TTFM experience in the first 1000 CABG operations. First 1000 patients had coronary artery bypass grafting (CABG performed in Cardiovascular Clinic, University Clinical Centre Tuzla, Bosnia and Herzegovina, between September, 1998 and September, 2003. CABG without use of cardio-pulmonary bypass (CPB-(OPCAB was used as the preferential surgical method both because this method is reported to have equal or better results than CABG with use of CPB (ONCAB, and because of the significant cost savings realized. TTFM was routinely used in all grafts as a quality assurance measure. Criteria for a poor functioning graft were: low mean flow (MF, pul-satility index (PI above 5 and a poor diastolic flow pattern. When no reversible cause of poor TTFM results were identified the graft was revised. A total of 1394 grafts in OPCAB group and 1478 in ONCAB group were performed. A total of 38 grafts (2,72% in 37 patients (7,07% were revised in OPCAB group, and 26 grafts (1,75% in 26 patients (5,45% in ONCAB group. 1 patient in OPCAB group needed 2 graft revisions. Graft revisions were more common in OPCAB, but with no significant difference (p=0,1035. The most frequently revised graft was LAD graft in both groups. Although the percentage of grafts revised are relatively low, it is still very important to record TTFM. More than 5% of patients in both groups needed graft revision. Although TTFM does not guarantee that grafts will stay open for a prolonged period of time we certainly believe that grafts that are occluded at the time of surgery will continue to stay occluded. TTFM is especially critical in OPCAB surgery where the technical challenge of grafting is higher then in ONCAB.

  8. Significant prolongation of segmental pancreatic allograft survival in two species

    Energy Technology Data Exchange (ETDEWEB)

    Du Toit, D.F.; Heydenrych, J.J.

    1988-06-01

    A study was conducted to assess the suppression of segmental pancreatic allograft rejection by cyclosporine (CSA) alone in baboons and dogs, and subtotal marrow irradiation (TL1) alone and TL 1 in combination with CSA in baboons. Total pancreatectomy in the dog and primate provided a reliable diabetic model, induced an absolute deficiency of insulin and was uniformly lethal if not treated. Continuous administration of CSA in baboons resulted in modest allograft survival. As in baboons, dogs receiving CSA 25 mg/kg/d rendered moderate graft prolongation but a dose of 40 mg/kg/d resulted in significant graft survival (greater than 100 days) in 5 of 8 allograft recipients. Irradiation alone resulted in minimal baboon pancreatic allograft survival of 20 baboons receiving TL1 1,000 rad and CSA, 3 had graft survival greater than of 100 days. Of 15 baboons receiving TL1 800 rad and CSA, 6 had graft survival of greater than 100 days. In conclusion, CSA administration in dogs and TL1 in combination with CSA in baboons resulted in highly significant segmental pancreatic allograft survival.

  9. Significant prolongation of segmental pancreatic allograft survival in two species

    International Nuclear Information System (INIS)

    Du Toit, D.F.; Heydenrych, J.J.

    1988-01-01

    A study was conducted to assess the suppression of segmental pancreatic allograft rejection by cyclosporine (CSA) alone in baboons and dogs, and subtotal marrow irradiation (TL1) alone and TL 1 in combination with CSA in baboons. Total pancreatectomy in the dog and primate provided a reliable diabetic model, induced an absolute deficiency of insulin and was uniformly lethal if not treated. Continuous administration of CSA in baboons resulted in modest allograft survival. As in baboons, dogs receiving CSA 25 mg/kg/d rendered moderate graft prolongation but a dose of 40 mg/kg/d resulted in significant graft survival (greater than 100 days) in 5 of 8 allograft recipients. Irradiation alone resulted in minimal baboon pancreatic allograft survival of 20 baboons receiving TL1 1,000 rad and CSA, 3 had graft survival greater than of 100 days. Of 15 baboons receiving TL1 800 rad and CSA, 6 had graft survival of greater than 100 days. In conclusion, CSA administration in dogs and TL1 in combination with CSA in baboons resulted in highly significant segmental pancreatic allograft survival

  10. Albumin grafting on biomaterial surfaces using gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, K.R.

    1993-01-01

    Surface modification has been used extensively in various fields to introduce desirable surface properties without affecting the bulk properties of the material. In the area of biomaterials, the approach of surface modification offers an effective alternative to the synthesis of new biomaterials. The specific objective of this study was to modify different biomaterial surfaces by albumin grafting to improve their blood compatibility. The modified surfaces were characterized for surface-induced platelet activation and thrombus formation. This behavior was correlated with the conditions used for grafting. In particular, albumin was functionalized to introduce pendant double bonds into the molecule. The functionalized albumin was covalently attached to various surfaces, such as dimethyldichlorosilane-coated glass, polypropylene, polycarbonate, poly(vinyl chloride), and polyethylene by gamma-irradiation. Platelet adhesion and activation on these surfaces was examined using video microscopy and scanning electron microscopy. The extent of grafting was found to be dependent on the albumin concentration used for adsorption and the gamma-irradiation time. Release of the grafted albumin during exposure to blood was minimal. The albumin-grafted fibers maintained their thromboresistant properties even after storage at elevated temperatures for prolonged time periods. Finally, the approach was used to graft albumin on the PLEXUS Adult Hollow Fiber Oxygenators (Shiley). The blood compatibility of the grafted oxygenators improved significantly when compared to controls.

  11. Improvement of the polymer stability by radiation grafting

    International Nuclear Information System (INIS)

    Ranogajec, F.; Mlinac-Misak, M.

    2004-01-01

    Losses of the stabilizer due to extractability or volatility immediately affect the ultimate performance of polymer products. A new approach to increase the persistence of the stabilizer in the final product is to chemically bind it to the polymer backbone. Radiation grafting or crosslinking could be an efficient method for this, when the stabilizer is polymerizable. By a mutual gamma irradiation method photoprotector 2-hydroxy-4-(3-methacryloxy-2-hydroxy-propoxy) benzophenone has been readily grafted to low-density polyethylene in benzene, tetrahydrofuran and methanol solution, respectively. Surface grafting occurs in a methanol solution of stabilizer, while in benzene and tetrahydrofuran solutions of the stabilizer, grafting proceeds more or less in the inner parts of the polymeric film as well. UV stability tests and changes in the mechanical properties of artificially and naturally aged films indicate pronounced protective effect achieved by the grafted stabilizer. Surface grafting is an efficient photostabilization method since the grafted stabilizer is chemically bound to a polymeric surface and in this way the problem of evaporation of blended stabilizers during the prolonged use of polymeric materials is eliminated

  12. Escherichia coli exports cyclic AMP via TolC.

    Science.gov (United States)

    Hantke, Klaus; Winkler, Karin; Schultz, Joachim E

    2011-03-01

    In Escherichia coli more than 180 genes are regulated by the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex. However, more than 90% of cAMP that is made by intracellular adenylyl cyclases is found in the culture medium. How is cAMP exported from E. coli? In a tolC mutant, 0.03 mM IPTG (isopropyl-β-d-thiogalactopyranoside) was sufficient to induce β-galactosidase compared to 0.1 mM IPTG in the parent strain. In a cya mutant unable to produce cAMP about 1 mM extracellular cAMP was required to induce β-galactosidase, whereas in a cya tolC mutant 0.1 mM cAMP was sufficient. When cAMP in E. coli cya was generated intracellularly by a recombinant, weakly active adenylyl cyclase from Corynebacterium glutamicum, the critical level of cAMP necessary for induction of maltose degradation was only achieved in a tolC mutant and not in the parent strain. Deletion of a putative cAMP phosphodiesterase of E. coli, CpdA, resulted in a slightly similar, yet more diffuse phenotype. The data demonstrate that export of cAMP via TolC is a most efficient way of E. coli to lower high concentrations of cAMP in the cell and maintain its sensitivity in changing metabolic environments.

  13. Antifungal effect of antimicrobial peptides (AMPs LR14) derived from Lactobacillus plantarum strain LR/14 and their applications in prevention of grain spoilage.

    Science.gov (United States)

    Gupta, Ruchi; Srivastava, Sheela

    2014-09-01

    The concern for food safety has led to an increased interest in the development of novel antimicrobials. Keeping this aim in mind, we have investigated the antifungal effect of antimicrobial peptides (AMPs LR14) produced by Lactobacillus plantarum strain LR/14 against four spoilage fungi, namely, Aspergillus niger, Rhizopus stolonifer, Mucor racemosus and Penicillium chrysogenum. Interestingly, all the four fungi were inhibited, suggesting that AMPs LR14 exhibited anti-fungal property. The peptides inhibited both, the spore germination and hyphal growth, however, the former stage was found to be more susceptible. The hyphal extensions were also inhibited in a dose-dependent manner. Viability test of treated spores confirmed the fungicidal activity of AMPs LR14. AMPs LR14 were also studied for the prevention of wheat grain spoilage under storage. Unhygienic conditions in damp godowns and store-houses, lead to loss of food grains and make them unfit for human consumption due to microbial deterioration. The treatment of wheat seeds with AMPs LR14 prevented fungal growth even after a prolonged storage under laboratory conditions for ∼2.5 years. The carbohydrate and protein content of the AMPs LR14-treated seeds denoted no significant loss, but the seed viability was affected as germination was retarded. Such studies have not been reported for any bacteriocin/AMP to the best of our knowledge. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Is prolonged cold ischemia a contraindication to using kidneys from acute kidney injury donors?

    Science.gov (United States)

    Orlando, Giuseppe; Khan, Muhammad A; El-Hennawy, Hany; Farney, Alan C; Rogers, Jeffrey; Reeves-Daniel, Amber; Gautreaux, Michael D; Doares, William; Kaczmorski, Scott; Stratta, Robert J

    2018-03-01

    To determine the impact of prolonged cold ischemia time (CIT) on the outcome of acute kidney injury (AKI) renal grafts, we therefore performed a single-center retrospective analysis in adult patients receiving kidney transplantation (KT) from AKI donors. Outcomes were stratified according to duration of CIT. A total of 118 patients receiving AKI grafts were enrolled. Based on CIT, patients were stratified as follows: (i) 20 hours (P = NS). In the nine patients with CIT >40 hours, the 4-year DCGS rate was 100%. We conclude that prolonged CIT in AKI grafts may not adversely influence outcomes and so discard of AKI kidneys because of projected long CIT is not warranted when donors are wisely triaged. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. The interplay between cyclic AMP and insulin during obesity development

    DEFF Research Database (Denmark)

    Borkowski, Kamil

    Insulin and cAMP signalling are related to two opposite metabolic responses. Insulin secretion is elicited in response to food availability and trigger catabolic processes like lipogenesis and glycogen synthesis with a purpose of energy storage. On the other hand cAMP signalling is associated...... with stress and starvation and stimulates processes like glycogen degradation and lipolysis to distribute the stored energy through the body. Although in energy preserving tissues insulin inhibit cAMP signalling, in fat precursor cells cAMP potentiates insulin action and promote adipogenesis. Activation...... of exchange factor directly activated by cAMP (Epac) has been shown to be crucial for cAMP mediated potentiation of insulin signaling. In the current study I am trying to answer the question as to how cAMP accelerates adipogenesis in vivo as well as what is the role of Epac in cAMP mediated potentiation...

  16. AMP is an adenosine A1 receptor agonist.

    Science.gov (United States)

    Rittiner, Joseph E; Korboukh, Ilia; Hull-Ryde, Emily A; Jin, Jian; Janzen, William P; Frye, Stephen V; Zylka, Mark J

    2012-02-17

    Numerous receptors for ATP, ADP, and adenosine exist; however, it is currently unknown whether a receptor for the related nucleotide adenosine 5'-monophosphate (AMP) exists. Using a novel cell-based assay to visualize adenosine receptor activation in real time, we found that AMP and a non-hydrolyzable AMP analog (deoxyadenosine 5'-monophosphonate, ACP) directly activated the adenosine A(1) receptor (A(1)R). In contrast, AMP only activated the adenosine A(2B) receptor (A(2B)R) after hydrolysis to adenosine by ecto-5'-nucleotidase (NT5E, CD73) or prostatic acid phosphatase (PAP, ACPP). Adenosine and AMP were equipotent human A(1)R agonists in our real-time assay and in a cAMP accumulation assay. ACP also depressed cAMP levels in mouse cortical neurons through activation of endogenous A(1)R. Non-selective purinergic receptor antagonists (pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid and suramin) did not block adenosine- or AMP-evoked activation. Moreover, mutation of His-251 in the human A(1)R ligand binding pocket reduced AMP potency without affecting adenosine potency. In contrast, mutation of a different binding pocket residue (His-278) eliminated responses to AMP and to adenosine. Taken together, our study indicates that the physiologically relevant nucleotide AMP is a full agonist of A(1)R. In addition, our study suggests that some of the physiological effects of AMP may be direct, and not indirect through ectonucleotidases that hydrolyze this nucleotide to adenosine.

  17. AMPS Supporting Research and Technology (SR and T) report. Atmospheric, Magnetospheric and Plasmas in Space (AMPS) definition study

    Science.gov (United States)

    1976-01-01

    A listing of candidate technology areas that require additional study is presented. These candidate tasks, identified during the AMPS Phase B studies, are requisites to the design, development, and operation of the AMPS concept selected for preliminary design.

  18. AMP Deaminase 3 Deficiency Enhanced 5′-AMP Induction of Hypometabolism

    Science.gov (United States)

    Daniels, Isadora Susan; O′Brien, William G.; Nath, Vinay; Zhao, Zhaoyang; Lee, Cheng Chi

    2013-01-01

    A hypometabolic state can be induced in mice by 5′-AMP administration. Previously we proposed that an underlying mechanism for this hypometabolism is linked to reduced erythrocyte oxygen transport function due to 5′-AMP uptake altering the cellular adenylate equilibrium. To test this hypothesis, we generated mice deficient in adenosine monophosphate deaminase 3 (AMPD3), the key catabolic enzyme for 5′-AMP in erythrocytes. Mice deficient in AMPD3 maintained AMPD activities in all tissues except erythrocytes. Developmentally and morphologically, the Ampd3−/− mice were indistinguishable from their wild type siblings. The levels of ATP, ADP but not 5′-AMP in erythrocytes of Ampd3−/− mice were significantly elevated. Fasting blood glucose levels of the Ampd3−/− mice were comparable to wild type siblings. In comparison to wild type mice, the Ampd3−/− mice displayed a deeper hypometabolism with a significantly delayed average arousal time in response to 5′-AMP administration. Together, these findings demonstrate a central role of AMPD3 in the regulation of 5′-AMP mediated hypometabolism and further implicate erythrocytes in this behavioral response. PMID:24066180

  19. Genetic influence on prolonged gestation

    DEFF Research Database (Denmark)

    Laursen, Maja; Bille, Camilla; Olesen, Annette Wind

    2004-01-01

    OBJECTIVE: The purpose of this study was to test a possible genetic component to prolonged gestation. STUDY DESIGN: The gestational duration of single, first pregnancies by both female and male twins was obtained by linking the Danish Twin Registry, The Danish Civil Registration System, and the D...... factors. CONCLUSION: Maternal genes influence prolonged gestation. However, a substantial paternal genetic influence through the fetus was not found....

  20. Bone Graft Alternatives

    Science.gov (United States)

    ... spinal deformity, or who have some types of disc herniations. In certain types of spinal fusion, bone grafts ... Specialist SEARCH Download Brochure ENGLISH Related Treatments Cervical Disc Herniation Fusion Lumbar Disc Herniation {1} ##LOC[OK]## {1} ## ...

  1. Analysis of Cartilage-Polydioxanone Foil Composite Grafts

    Science.gov (United States)

    Kim, James H.; Wong, Brian

    2014-01-01

    This study presents an analytical investigation into the mechanical behavior of a cartilage-polydioxanone (PDS) plate composite grafts. Numerical methods are used to provide a first-order, numerical model of the flexural stiffness of a cartilage-PDS graft. Flexural stiffness is a measure of resistance to bending and is inversely related to the amount of deformation a structure may experience when subjected to bending forces. The cartilage-PDS graft was modeled as a single composite beam. Using Bernoulli-Euler beam theory, a closed form equation for the theoretical flexural stiffness of the composite graft was developed. A parametric analysis was performed to see how the flexural properties of the composite model changed with varying thicknesses of PDS foil. The stiffness of the cartilage-PDS composite using 0.15-mm-thick PDS was four times higher than cartilage alone. The composite with a 0.5-mm-thick PDS graft was only 1.7 times stiffer than the composite with the 0.15-mm-thick PDS graft. Although a thicker graft material will yield higher flexural stiffness for the composite, the relationship between composite stiffness and PDS thickness is nonlinear. After a critical point, increments in graft thickness produce gradually smaller improvements in flexural stiffness. The small increase in stiffness when using the thicker PDS foils versus the 0.15 mm PDS foil may not be worth the potential complications (prolonged foreign body reaction, reduction in nutrient diffusion to cartilage) of using thicker artificial grafts. PMID:24327249

  2. Antifungal activity of synthetic peptides derived from Impatiens balsamina antimicrobial peptides Ib-AMP1 and Ib-AMP4

    NARCIS (Netherlands)

    Thevissen, K.; Francois, E.J.A.; Sijtsma, L.; Amerongen, van A.; Schaaper, W.M.M.; Meloen, R.; Posthuma-Trumpie, G.A.; Broekaert, W.F.; Cammue, B.P.A.

    2005-01-01

    Seeds of Impatiens balsamina contain a set of related antimicrobial peptides (Ib-AMPs). We have produced a synthetic variant of Ib-AMP1, oxidized to the bicyclic native conformation, which was fully active on yeast and fungal strains; and four linear 20-mer Ib-AMP variants, including two all-d

  3. The therapeutic applications of antimicrobial peptides (AMPs): a patent review.

    Science.gov (United States)

    Kang, Hee-Kyoung; Kim, Cheolmin; Seo, Chang Ho; Park, Yoonkyung

    2017-01-01

    Antimicrobial peptides (AMPs) are small molecules with a broad spectrum of antibiotic activities against bacteria, yeasts, fungi, and viruses and cytotoxic activity on cancer cells, in addition to anti-inflammatory and immunomodulatory activities. Therefore, AMPs have garnered interest as novel therapeutic agents. Because of the rapid increase in drug-resistant pathogenic microorganisms, AMPs from synthetic and natural sources have been developed using alternative antimicrobial strategies. This article presents a broad analysis of patents referring to the therapeutic applications of AMPs since 2009. The review focuses on the universal trends in the effective design, mechanism, and biological evolution of AMPs.

  4. S-AMP: Approximate Message Passing for General Matrix Ensembles

    DEFF Research Database (Denmark)

    Cakmak, Burak; Winther, Ole; Fleury, Bernard H.

    2014-01-01

    We propose a novel iterative estimation algorithm for linear observation models called S-AMP. The fixed points of S-AMP are the stationary points of the exact Gibbs free energy under a set of (first- and second-) moment consistency constraints in the large system limit. S-AMP extends...... the approximate message-passing (AMP) algorithm to general matrix ensembles with a well-defined large system size limit. The generalization is based on the S-transform (in free probability) of the spectrum of the measurement matrix. Furthermore, we show that the optimality of S-AMP follows directly from its...

  5. Pediatric burn wound impetigo after grafting.

    Science.gov (United States)

    Aikins, Kimberly; Prasad, Narayan; Menon, Seema; Harvey, John G; Holland, Andrew J A

    2015-01-01

    Modern burn care techniques have reduced the risk of infection of the acute burn wound, resulting in more rapid healing and a lower incidence of graft loss. Secondary breakdown may still occur. The loss of epithelium in association with multifocal superficial abscesses and ulceration has been termed burns impetigo. This may result in considerable morbidity and require prolonged treatment. The events preceding development, the impact on the patient, and the ideal treatment appear unclear and poorly reported. In 5 years, between 2006 and 2011, 406 pediatric burns were treated with skin grafts, with 7% developing burns impetigo. Time to resolution ranged from 5 to 241 days: the mean time to complete healing was greatest with conservative management (96 days), followed by antibacterial dressings (37 days), oral antibiotics (36 days), topical steroids (16 days), and oral antibiotics in combination with topical steroids (13.5 days). Burns impetigo resulted in significant morbidity, requiring multiple visits to the treatment center and prolonged symptoms. Delay in diagnosis and treatment resulted in worse outcomes. Prompt consideration of burns impetigo should occur when postgraft patients present with suggestive clinical signs and treatment with oral antibiotics plus topical steroids should be considered.

  6. modlAMP: Python for antimicrobial peptides.

    Science.gov (United States)

    Müller, Alex T; Gabernet, Gisela; Hiss, Jan A; Schneider, Gisbert

    2017-09-01

    We have implemented the lecular esign aboratory's nti icrobial eptides package ( ), a Python-based software package for the design, classification and visual representation of peptide data. modlAMP offers functions for molecular descriptor calculation and the retrieval of amino acid sequences from public or local sequence databases, and provides instant access to precompiled datasets for machine learning. The package also contains methods for the analysis and representation of circular dichroism spectra. The modlAMP Python package is available under the BSD license from URL http://doi.org/10.5905/ethz-1007-72 or via pip from the Python Package Index (PyPI). gisbert.schneider@pharma.ethz.ch. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  7. 2′,3′-cAMP, 3′-AMP, and 2′-AMP inhibit human aortic and coronary vascular smooth muscle cell proliferation via A2B receptors

    Science.gov (United States)

    Ren, Jin; Gillespie, Delbert G.

    2011-01-01

    Rat vascular smooth muscle cells (VSMCs) from renal microvessels metabolize 2′,3′-cAMP to 2′-AMP and 3′-AMP, and these AMPs are converted to adenosine that inhibits microvascular VSMC proliferation via A2B receptors. The goal of this study was to test whether this mechanism also exists in VSMCs from conduit arteries and whether it is similarly expressed in human vs. rat VSMCs. Incubation of rat and human aortic VSMCs with 2′,3′-cAMP concentration-dependently increased levels of 2′-AMP and 3′-AMP in the medium, with a similar absolute increase in 2′-AMP vs. 3′-AMP. In contrast, in human coronary VSMCs, 2′,3′-cAMP increased 2′-AMP levels yet had little effect on 3′-AMP levels. In all cell types, 2′,3′-cAMP increased levels of adenosine, but not 5′-AMP, and 2′,3′-AMP inhibited cell proliferation. Antagonism of A2B receptors (MRS-1754), but not A1 (1,3-dipropyl-8-cyclopentylxanthine), A2A (SCH-58261), or A3 (VUF-5574) receptors, attenuated the antiproliferative effects of 2′,3′-cAMP. In all cell types, 2′-AMP, 3′-AMP, and 5′-AMP increased adenosine levels, and inhibition of ecto-5′-nucleotidase blocked this effect of 5′-AMP but not that of 2′-AMP nor 3′-AMP. Also, 2′-AMP, 3′-AMP, and 5′-AMP, like 2′,3′-cAMP, exerted antiproliferative effects that were abolished by antagonism of A2B receptors with MRS-1754. In conclusion, VSMCs from conduit arteries metabolize 2′,3′-cAMP to AMPs, which are metabolized to adenosine. In rat and human aortic VSMCs, both 2′-AMP and 3′-AMP are involved in this process, whereas, in human coronary VSMCs, 2′,3′-cAMP is mainly converted to 2′-AMP. Because adenosine inhibits VSMC proliferation via A2B receptors, local vascular production of 2′,3′-cAMP may protect conduit arteries from atherosclerosis. PMID:21622827

  8. Fiscal Year 2011 Infrastructure Refactorizations in AMP

    Energy Technology Data Exchange (ETDEWEB)

    Berrill, Mark A [ORNL; Philip, Bobby [ORNL; Sampath, Rahul S [ORNL; Allu, Srikanth [ORNL; Barai, Pallab [ORNL; Cochran, Bill [ORNL; Clarno, Kevin T [ORNL; Dilts, Gary A [ORNL

    2011-09-01

    In Fiscal Year 2011 (FY11), the AMP (Advanced MultiPhysics) Nuclear Fuel Performance code [1] went through a thorough review and refactorization based on the lessons-learned from the previous year, in which the version 0.9 of the software was released as a prototype. This report describes the refactorization work that has occurred or is in progress during FY11.

  9. The Monge-Ampère equation

    CERN Document Server

    Gutiérrez, Cristian E

    2016-01-01

    Now in its second edition, this monograph explores the Monge-Ampère equation and the latest advances in its study and applications. It provides an essentially self-contained systematic exposition of the theory of weak solutions, including regularity results by L. A. Caffarelli. The geometric aspects of this theory are stressed using techniques from harmonic analysis, such as covering lemmas and set decompositions. An effort is made to present complete proofs of all theorems, and examples and exercises are offered to further illustrate important concepts. Some of the topics considered include generalized solutions, non-divergence equations, cross sections, and convex solutions. New to this edition is a chapter on the linearized Monge-Ampère equation and a chapter on interior Hölder estimates for second derivatives. Bibliographic notes, updated and expanded from the first edition, are included at the end of every chapter for further reading on Monge-Ampère-type equations and their diverse applications in th...

  10. The Applied Mathematics for Power Systems (AMPS)

    Energy Technology Data Exchange (ETDEWEB)

    Chertkov, Michael [Los Alamos National Laboratory

    2012-07-24

    Increased deployment of new technologies, e.g., renewable generation and electric vehicles, is rapidly transforming electrical power networks by crossing previously distinct spatiotemporal scales and invalidating many traditional approaches for designing, analyzing, and operating power grids. This trend is expected to accelerate over the coming years, bringing the disruptive challenge of complexity, but also opportunities to deliver unprecedented efficiency and reliability. Our Applied Mathematics for Power Systems (AMPS) Center will discover, enable, and solve emerging mathematics challenges arising in power systems and, more generally, in complex engineered networks. We will develop foundational applied mathematics resulting in rigorous algorithms and simulation toolboxes for modern and future engineered networks. The AMPS Center deconstruction/reconstruction approach 'deconstructs' complex networks into sub-problems within non-separable spatiotemporal scales, a missing step in 20th century modeling of engineered networks. These sub-problems are addressed within the appropriate AMPS foundational pillar - complex systems, control theory, and optimization theory - and merged or 'reconstructed' at their boundaries into more general mathematical descriptions of complex engineered networks where important new questions are formulated and attacked. These two steps, iterated multiple times, will bridge the growing chasm between the legacy power grid and its future as a complex engineered network.

  11. Copper Regulates Cyclic AMP-Dependent Lipolysis

    Science.gov (United States)

    Krishnamoorthy, Lakshmi; Cotruvo, Joseph A.; Chan, Jefferson; Kaluarachchi, Harini; Muchenditsi, Abigael; Pendyala, Venkata S.; Jia, Shang; Aron, Allegra T.; Ackerman, Cheri M.; Vander Wal, Mark N.; Guan, Timothy; Smaga, Lukas P.; Farhi, Samouil L.; New, Elizabeth J.; Lutsenko, Svetlana; Chang, Christopher J.

    2016-01-01

    Cell signaling relies extensively on dynamic pools of redox-inactive metal ions such as sodium, potassium, calcium, and zinc, but their redox-active transition metal counterparts such as copper and iron have been studied primarily as static enzyme cofactors. Here we report that copper is an endogenous regulator of lipolysis, the breakdown of fat, which is an essential process in maintaining the body's weight and energy stores. Utilizing a murine model of genetic copper misregulation, in combination with pharmacological alterations in copper status and imaging studies in a 3T3-L1 white adipocyte model, we demonstrate that copper regulates lipolysis at the level of the second messenger, cyclic AMP (cAMP), by altering the activity of the cAMP-degrading phosphodiesterase PDE3B. Biochemical studies of the copper-PDE3B interaction establish copper-dependent inhibition of enzyme activity and identify a key conserved cysteine residue within a PDE3-specific loop that is essential for the observed copper-dependent lipolytic phenotype. PMID:27272565

  12. Optimal Design for Reactivity Ratio Estimation: A Comparison of Techniques for AMPS/Acrylamide and AMPS/Acrylic Acid Copolymerizations

    Directory of Open Access Journals (Sweden)

    Alison J. Scott

    2015-11-01

    Full Text Available Water-soluble polymers of acrylamide (AAm and acrylic acid (AAc have significant potential in enhanced oil recovery, as well as in other specialty applications. To improve the shear strength of the polymer, a third comonomer, 2-acrylamido-2-methylpropane sulfonic acid (AMPS, can be added to the pre-polymerization mixture. Copolymerization kinetics of AAm/AAc are well studied, but little is known about the other comonomer pairs (AMPS/AAm and AMPS/AAc. Hence, reactivity ratios for AMPS/AAm and AMPS/AAc copolymerization must be established first. A key aspect in the estimation of reliable reactivity ratios is design of experiments, which minimizes the number of experiments and provides increased information content (resulting in more precise parameter estimates. However, design of experiments is hardly ever used during copolymerization parameter estimation schemes. In the current work, copolymerization experiments for both AMPS/AAm and AMPS/AAc are designed using two optimal techniques (Tidwell-Mortimer and the error-in-variables-model (EVM. From these optimally designed experiments, accurate reactivity ratio estimates are determined for AMPS/AAm (rAMPS = 0.18, rAAm = 0.85 and AMPS/AAc (rAMPS = 0.19, rAAc = 0.86.

  13. Axillobifemoral bypass grafting

    Directory of Open Access Journals (Sweden)

    Davidović Lazar B.

    2004-01-01

    Full Text Available INTRODUCTION Axillo-femoral bypass (AxF means connecting the axillar and femoral artery with the graft that is placed subcutaneously [1]. Usually, this graft is connected with contralateral femoral artery via one accessory subcutaneous graft, and this connection is known as axillobifemoral bypass (AxFF. This extra-anatomic procedure is an alternative method to the standard reconstruction of aortoiliac region when there are contraindications for general or local reasons. OBJECTIVE The objective of this paper is to show early and late results of AxFF bypass grafting as well as to show the indications for AxFF bypass. METHODS The sample consisted of 37 patients. The procedure was performed in 28 patients who suffered from aortoiliac occlusive disease and who were at high risk due to the comorbidity- in one patient with the rupture of juxtarenal aneurysm of abdominal aorta; in five patients with aortoenteric fistula, in two patients with iatrogenic lesion of abdominal aorta and in one female patient with anus preternaturalis definitivus who was treated for rectovaginal fistula. Donor's right axillary artery was used in 26 cases (70.3%, and donor's left axillary artery was used in 9 cases (29.7%. Dacron graft was used in 34 patients and Polytetrafluo-roethlylene graft was used in three patients. Simultaneously, profundo-plastic was done in four patients and femoro-popliteal bypass was performed in three patients. In five patients who suffered from aortoenteric fistula, simultaneous intervention of gastrointerstinal system has been done, x2 test was used for statistical evaluation and life table method was used for verification of late graft patency. RESULTS The rate of early postoperative mortality was 13.5%. The causes of death were: sepsis -1, MOFS - 3, and infarct myocardium -1. The mean follow up period was 40.1 months, ranging from six months to 17 years. During the follow up period, an early graft thrombosis was identified in two and late graft

  14. Deciphering the actions of antiparkinsonian and antipsychotic drugs on cAMP/DARPP-32 signaling

    Directory of Open Access Journals (Sweden)

    Gilberto eFisone

    2011-07-01

    Full Text Available The basal ganglia are affected by several neuropsychiatric and neurodegenerative diseases, many of which are treated with drugs acting on the dopamine system. For instance, the loss of dopaminergic input to the striatum, which is the main pathological feature of Parkinson’s disease (PD, is counteracted by administering the dopamine precursor, L-DOPA. Furthermore, psychotic disorders, including schizophrenia, are treated with drugs that act as antagonists at the D2-type of dopamine receptor (D2R. The use of L-DOPA and typical antipsychotic drugs, such as haloperidol, is limited by the emergence of motor side effects, particularly after prolonged use. Striatal medium spiny neurons (MSNs represent an ideal tool to investigate the molecular changes implicated in these conditions. MSNs receive a large glutamatergic innervation from cortex, thalamus and limbic structures, which is controlled by dopaminergic projections originating in the midbrain. There are two large populations of striatal MSNs, which differ based on their connectivity to the output nuclei of the basal ganglia and on their ability to express dopamine D1 receptors (D1Rs or D2Rs. Administration of L-DOPA promotes cAMP signaling and activates the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32 in the D1R-expressing MSNs, which form the striatonigral, direct pathway. Conversely, haloperidol activates the cAMP/DARPP-32 cascade in D2R-expressing MSNs, which form the striatopallidal, indirect pathway. This review describes the effects produced on downstream effector proteins by stimulation of cAMP/DARPP-32 signaling in these two groups of MSNs. Particular emphasis is given to the regulation of the GluR1 subunit of the AMPA glutamate receptor, the extracellular signal-regulated protein kinases 1 and 2 (ERK, focusing on functional role and potential pathological relevance.

  15. Deciphering the Actions of Antiparkinsonian and Antipsychotic Drugs on cAMP/DARPP-32 Signaling.

    Science.gov (United States)

    Bonito-Oliva, Alessandra; Feyder, Michael; Fisone, Gilberto

    2011-01-01

    The basal ganglia are affected by several neuropsychiatric and neurodegenerative diseases, many of which are treated with drugs acting on the dopamine system. For instance, the loss of dopaminergic input to the striatum, which is the main pathological feature of Parkinson's disease, is counteracted by administering the dopamine precursor, L-DOPA. Furthermore, psychotic disorders, including schizophrenia, are treated with drugs that act as antagonists at the D2-type of dopamine receptor (D2R). The use of L-DOPA and typical antipsychotic drugs, such as haloperidol, is limited by the emergence of motor side-effects, particularly after prolonged use. Striatal medium spiny neurons (MSNs) represent an ideal tool to investigate the molecular changes implicated in these conditions. MSNs receive a large glutamatergic innervation from cortex, thalamus, and limbic structures, and are controlled by dopaminergic projections originating in the midbrain. There are two large populations of striatal MSNs, which differ based on their connectivity to the output nuclei of the basal ganglia and on their ability to express dopamine D1 receptors (D1Rs) or D2Rs. Administration of L-DOPA promotes cAMP signaling and activates the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32) in the D1R-expressing MSNs, which form the striatonigral, or direct pathway. Conversely, haloperidol activates the cAMP/DARPP-32 cascade in D2R-expressing MSNs, which form the striatopallidal, or indirect pathway. This review describes the effects produced on downstream effector proteins by stimulation of cAMP/DARPP-32 signaling in these two groups of MSNs. Particular emphasis is given to the regulation of the GluR1 subunit of the α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate glutamate receptor, the extracellular signal-regulated protein kinases 1 and 2, focusing on functional role and potential pathological relevance.

  16. Grafts for Ridge Preservation

    Science.gov (United States)

    Jamjoom, Amal; Cohen, Robert E.

    2015-01-01

    Alveolar ridge bone resorption is a biologic phenomenon that occurs following tooth extraction and cannot be prevented. This paper reviews the vertical and horizontal ridge dimensional changes that are associated with tooth extraction. It also provides an overview of the advantages of ridge preservation as well as grafting materials. A Medline search among English language papers was performed in March 2015 using alveolar ridge preservation, ridge augmentation, and various graft types as search terms. Additional papers were considered following the preliminary review of the initial search that were relevant to alveolar ridge preservation. The literature suggests that ridge preservation methods and augmentation techniques are available to minimize and restore available bone. Numerous grafting materials, such as autografts, allografts, xenografts, and alloplasts, currently are used for ridge preservation. Other materials, such as growth factors, also can be used to enhance biologic outcome. PMID:26262646

  17. [Chickenpox, burns and grafts].

    Science.gov (United States)

    Rojas Zegers, J; Fidel Avendaño, L

    1979-01-01

    An outbreak of chickenpox that occurred at the Burns Repair Surgery Unit, Department of Children's Surgery, Hospital R. del Río, between June and November, 1975, is reported. 27 cases of burned children were studied, including analysis of correlations of the stages and outcome of the disease (varicela), the trauma (burns) and the graft (repair surgery). As a result, the authors emphasize the following findings: 1. Burns and their repair are not aggravating factors for varicella. In a small number of cases the exanthema looked more confluent in the graft surgical areas and in the first degree burns healing spontaneously. 2. Usually there was an uneventful outcome of graft repair surgery on a varicella patient, either during the incubation period, the acme or the convalescence. 3. The fact that the outmost intensity of secondary viremia of varicella occurs before the onset of exanthemia, that is, during the late incubation period, is confirmed.

  18. Radiation induced graft copolymerization of cellulosic fabric waste and its application in the removal of cyanide and dichromate from aqueous solution

    International Nuclear Information System (INIS)

    El-Kelesh, N.A.; Hashem, A.; Sokker, H.H.; Abd Elaal, S.E.

    2005-01-01

    Graft polymerization and crosslinking in radiation processing are attractive techniques for modification of the chemical and physical properties of the conventional polymers. The graft polymerization and subsequent chemical treatment can introduce a chelate agent function into a conventional polymer such as cellulosic fabric. Cellulosic graft copolymers were prepared by the reaction of the fiber with acrylonitrile (AN) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) in DMF initiated by gamma-radiation 60 Co. The grafted fabric was chemically treated with hydroxyl amine to obtain amidoxime form. Factors affecting on the grafting such as radiation dose, monomer concentration and solvent concentration as well as monomer composition was investigated. The chemically modified graft fabric was applied for recovery of cyanide and dichromate from aqueous solution. The CN show removal percent 89%, whereas dichromate has 65% removal percent

  19. Arteriovenous shunt graft ulceration with sinus and graft epithelialization

    Directory of Open Access Journals (Sweden)

    Pooja Singhal

    2015-03-01

    Full Text Available Arteriovenous fistula and grafts are used as access sites for patients with chronic kidney disease and are prone for complications. Stent grafts are used to treat access site complications. We report a rare and unusual finding of epithelialization of the sinus tract and the lumen of a polytetrafluoroethylene graft, following ulceration of the overlying skin.

  20. Stabilization of Foam Lamella Using Novel Surface-Grafted Nanocellulose-Based Nanofluids.

    Science.gov (United States)

    Wei, Bing; Li, Hao; Li, Qinzhi; Wen, Yangbing; Sun, Lin; Wei, Peng; Pu, Wanfen; Li, Yibo

    2017-05-30

    To solve the potential risk of present oilfield chemistries to subterranean environment, our group contributes to the development of "green" petroleum production processes. This proof-of-concept research studied the well-defined nanocellulose-based nanofluids, i.e., original (NC), AMPS grafted (NC-KY), and AMPS and hydrophobic chains grafted (NC-KYSS), in stabilizing foam lamella for potential use in enhanced oil recovery (EOR). The data showed that the collaboration of the surface-functional nanocellulose considerately improved the foam stability particularly in the presence of hydrocarbons due to the thickened foam film coupled with the molecular interactions at interior lamella. Since the grafted AMPS and alkyl chains, NC-KYSS noticeably enhanced foam quality compared against NC and NC-KY. With the increase in gas pressure, the lamella stabilizing effect of NC-KYSS became increasingly significant. The coflowing behaviors of foam with oleic phase in porous media were examined in a five-spot visualization micromodel (15 cm × 15 cm × 1 cm) and identified using a digital analysis method. The defoaming/destabilizing effect of hydrocarbons was fairly notable in porous media, causing the foam to finger through the formed "oil bank". However, a tough displacement front was constructed when the surfactant synergized with NC-KYSS due to the stabilized foam lamella and 12% of incremental oil recovery was produced.

  1. Serum biochemical changes accompanying prolonged ...

    African Journals Online (AJOL)

    Jane

    2010-10-18

    Oct 18, 2010 ... Toxicological evaluation of the whole fruit of Lagenaria breviflora was carried out using the serum biochemical changes accompanying prolonged administration of the ethanolic extract of the fruit in ... glucose in rats administered with the extract of 8000 mg/kg body weight increased two and half-fold.

  2. Measures that Prolong Work Life.

    Science.gov (United States)

    Nusberg, Charlotte

    1986-01-01

    Discusses measures that have been adopted by France, Great Britain, Sweden, the Netherlands, the United States, and Japan to prolong the work life of older workers. Measures include job transfer and exemption, dismissal protection, retirement policies, and reintegration of unemployed older workers. (JOW)

  3. Prolonged unexplained fatigue in paediatrics

    NARCIS (Netherlands)

    Bakker, R.J.

    2010-01-01

    Prolonged Unexplained Fatigue in Paediatrics. Fatigue, as the result of mental or physical exertion, will disappear after rest, drinks and food. Fatigue as a symptom of illness will recover with the recovering of the illness. But when fatigue is ongoing for a long time, and not the result of

  4. Physiology Of Prolonged Bed Rest

    Science.gov (United States)

    Greenleaf, John E.

    1991-01-01

    Report describes physiological effects of prolonged bed rest. Rest for periods of 24 hours or longer deconditions body to some extent; healing proceeds simultaneously with deconditioning. Report provides details on shifts in fluid electrolytes and loss of lean body mass, which comprises everything in body besides fat - that is, water, muscle, and bone. Based on published research.

  5. An unique case of thoracic endovascular aortic repair (TEVAR) graft infection with Streptococcus viridans.

    Science.gov (United States)

    Zubaidah, N H; Azim, M I M; Osama, M H; Harunarashid, H; Das, S

    2012-01-01

    The incidence of infection following TEVAR is low. To the best of our knowledge, this is the first case report of post thoracic endovascular aortic repair (TEVAR) with Streptococcus viridans graft infection. A 54-year-old male underwent TEVAR for dissecting thoracic aneurysm with spinal ischaemia. He had an eventful recovery with prolonged period of stay in intensive care unit. Three months later, he presented with persistent chest discomfort and fever. Computed tomography (CT) of the thorax revealed evidence of graft infection and the blood culture grew Streptococcus viridans. The rarity of TEVAR graft infection due to Streptococcus viridans and its management are being discussed.

  6. Graft nephrectomy: The SGPGI experience

    OpenAIRE

    Nand Kishore Arvind; Aneesh Srivastava; Anant Kumar; Subodh K Das

    2002-01-01

    Background: Graft nephrectomy is often considered a hazardous procedure with high morbidity and occasional mortality, and this may pose a technical challenge. The aim of this study was to evaluate the indications, etiology and complications following graft nephrectomy. Materials and Methods: From 1988 to 2001, among total of 1,019 live related renal transplants carried at our center, 46 underwent graft nephrectomy. Patients were divided into 2 groups depending on timing of graft re-mova...

  7. Bronchoprotection by salmeterol: cell stabilization or functional antagonism? Comparative effects on histamine- and AMP-induced bronchoconstriction.

    Science.gov (United States)

    Solèr, M; Joos, L; Bolliger, C T; Elsasser, S; Perruchoud, A P

    1994-11-01

    Salmeterol provides bronchoprotection against a number of constrictor stimuli for more than 12 h after a single dose. This effect could be due either to functional antagonism at the level of airway smooth muscle or to cell-stabilizing effects of the compound. In this study, we attempted to clarify this mechanism by comparing the effects of salmeterol (50 micrograms), salbutamol (200 micrograms) and placebo on the airway responsiveness to histamine (to assess functional antagonism), and to adenosine 5'-monophosphate (AMP) (to assess additional cell-stabilizing effects), 14 h after drug treatment. Thirteen patients with mild allergic asthma were studied in a double-blind, randomized protocol on 6 days, at least 48 h apart. Forced expiratory volume in one second (FEV1) was measured before and 15 min after inhalation of the study medication. Then, 14 h later (8 a.m. the following morning), a bronchoprovocation test with histamine or AMP was performed. We found that 14 h after inhalation, salmeterol still had a significant effect on FEV1 in comparison to placebo and salbutamol. The provocative dose producing a 20% fall in FEV1 (PD20histamine) was significantly increased after salmeterol, whilst the increase in PD20AMP did not reach significance. The shift in PD20 (in doubling dose steps) induced by salmeterol pretreatment was not different between histamine and AMP. We conclude that the prolonged protective effect of salmeterol occurs via an extended bronchodilating and functional antagonistic action and not via a cell-stabilizing effect.

  8. The Phosphorylation Status of a Cyclic AMP-Responsive Activator Is Modulated via a Chromatin-Dependent Mechanism

    Science.gov (United States)

    Michael, Laura F.; Asahara, Hiroshi; Shulman, Andrew I.; Kraus, W. Lee; Montminy, Marc

    2000-01-01

    Cyclic AMP (cAMP) stimulates the expression of numerous genes via the protein kinase A (PKA)-mediated phosphorylation of CREB at Ser133. Ser133 phosphorylation, in turn, promotes recruitment of the coactivator CREB binding protein and its paralog p300, histone acetyltransferases (HATs) that have been proposed to mediate target gene activation, in part, by destabilizing promoter bound nucleosomes and thereby allowing assembly of the transcriptional apparatus. Here we show that although histone deacetylase (HDAC) inhibitors potentiate target gene activation via cAMP, they do not stimulate transcription over the early burst phase, during which CREB phosphorylation and CBP/p300 recruitment are maximal. Rather, HDAC inhibitors augment CREB activity during the late attenuation phase by prolonging CREB phosphorylation on chromosomal but, remarkably, not on extrachromosomal templates. In reconstitution studies, assembly of periodic nucleosomal arrays on a cAMP-responsive promoter template potently inhibited CREB phosphorylation by PKA, and acetylation of these template-bound nucleosomes by p300 partially rescued CREB phosphorylation by PKA. Our results suggest a novel regulatory mechanism by which cellular HATs and HDACs modulate the phosphorylation status of nuclear activators in response to cellular signals. PMID:10669737

  9. The interplay between cyclic AMP and insulin during obesity development

    DEFF Research Database (Denmark)

    Borkowski, Kamil

    with stress and starvation and stimulates processes like glycogen degradation and lipolysis to distribute the stored energy through the body. Although in energy preserving tissues insulin inhibit cAMP signalling, in fat precursor cells cAMP potentiates insulin action and promote adipogenesis. Activation...... of exchange factor directly activated by cAMP (Epac) has been shown to be crucial for cAMP mediated potentiation of insulin signaling. In the current study I am trying to answer the question as to how cAMP accelerates adipogenesis in vivo as well as what is the role of Epac in cAMP mediated potentiation...... of insulin signalling. Moreover, I am investigating how increased insulin secretion caused by sucrose consumption, affects insulin signaling in peripheral tissues....

  10. Haemodynamics in axillobifemoral bypass grafts

    NARCIS (Netherlands)

    C.H. Wittens

    1992-01-01

    textabstractThis thesis is based on four publications on the subject of graft configuration and haemodynamics in axillobifemoral bypass grafts: 1. A clinical evaluation of 17 patients with axillobifemoral bypass graft operations, performed for various indications. Two important observations were

  11. Detection of imminent vein graft occlusion: what is the optimal surveillance program?

    Science.gov (United States)

    Tinder, Chelsey N; Bandyk, Dennis F

    2009-12-01

    The prediction of infrainguinal vein bypass failure remains an inexact judgment. Patient demographics, technical factors, and vascular laboratory graft surveillance testing are helpful in identifying a high-risk graft cohort. The optimal surveillance program to detect the bypass at risk for imminent occlusion continues to be developed, but required elements are known and include clinical assessment for new or changes in limb ischemia symptoms, measurement of ankle and/or toe systolic pressure, and duplex ultrasound imaging of the bypass graft. Duplex ultrasound assessment of bypass hemodynamics may be the most accurate method to detect imminent vein graft occlusion. The finding of low graft flow during intraoperative assessment or at a scheduled surveillance study predicts failure; and if associated with an occlusive lesion, a graft revision can prolong patency. The most common abnormality producing graft failure is conduit stenosis caused by myointimal hyperplasia; and the majority can be repaired by an endovascular intervention. Frequency of testing to detect the failing bypass should be individualized to the patient, the type of arterial bypass, and prior duplex ultrasound scan findings. The focus of surveillance is on identification of the low-flow arterial bypass and timely repair of detected critical stenosis defined by duplex velocity spectra criteria of a peak systolic velocity 300 cm/s and peak systolic velocity ratio across the stenosis >3.5-correlating with >70% diameter-reducing stenosis. When conducted appropriately, a graft surveillance program should result in an unexpected graft failure rate of <3% per year.

  12. Didactical formulation of the Ampère law

    International Nuclear Information System (INIS)

    Barchiesi, Dominique

    2014-01-01

    The Ampère law is useful to calculate the magnetostatic field in the cases of distributions of current with high degree of symmetry. Nevertheless the magnetic field produced by a thin straight wire carrying a current I requires the Biot–Savart law and the use of the Ampère law leads to a mistake. A didactical formulation of the Ampère law is proposed to prevent misinterpretations. (letters and comments)

  13. AMP Is an Adenosine A1 Receptor Agonist*

    Science.gov (United States)

    Rittiner, Joseph E.; Korboukh, Ilia; Hull-Ryde, Emily A.; Jin, Jian; Janzen, William P.; Frye, Stephen V.; Zylka, Mark J.

    2012-01-01

    Numerous receptors for ATP, ADP, and adenosine exist; however, it is currently unknown whether a receptor for the related nucleotide adenosine 5′-monophosphate (AMP) exists. Using a novel cell-based assay to visualize adenosine receptor activation in real time, we found that AMP and a non-hydrolyzable AMP analog (deoxyadenosine 5′-monophosphonate, ACP) directly activated the adenosine A1 receptor (A1R). In contrast, AMP only activated the adenosine A2B receptor (A2BR) after hydrolysis to adenosine by ecto-5′-nucleotidase (NT5E, CD73) or prostatic acid phosphatase (PAP, ACPP). Adenosine and AMP were equipotent human A1R agonists in our real-time assay and in a cAMP accumulation assay. ACP also depressed cAMP levels in mouse cortical neurons through activation of endogenous A1R. Non-selective purinergic receptor antagonists (pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid and suramin) did not block adenosine- or AMP-evoked activation. Moreover, mutation of His-251 in the human A1R ligand binding pocket reduced AMP potency without affecting adenosine potency. In contrast, mutation of a different binding pocket residue (His-278) eliminated responses to AMP and to adenosine. Taken together, our study indicates that the physiologically relevant nucleotide AMP is a full agonist of A1R. In addition, our study suggests that some of the physiological effects of AMP may be direct, and not indirect through ectonucleotidases that hydrolyze this nucleotide to adenosine. PMID:22215671

  14. Acrylonitrile grafted to PVDF

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jin; Eitouni, Hany Basam

    2015-03-31

    PVDF-g-PAN has been synthesized by grafting polyacrylonitrile onto polyvinylidene fluoride using an ATRP/AGET method. The novel polymer is ionically conducive and has much more flexibility than PVDF alone, making it especially useful either as a binder in battery cell electrodes or as a polymer electrolyte in a battery cell.

  15. Aortic Graft Infection Secondary to Iatrogenic Transcolonic Graft Malposition.

    Science.gov (United States)

    Blank, Jacqueline J; Rothstein, Abby E; Lee, Cheong Jun; Malinowski, Michael J; Lewis, Brian D; Ridolfi, Timothy J; Otterson, Mary F

    2018-01-01

    Aortic graft infections are a rare but devastating complication of aortic revascularization. Often infections occur due to contamination at the time of surgery. Iatrogenic misplacement of the limbs of an aortobifemoral graft is exceedingly rare, and principles of evaluation and treatment are not well defined. We report 2 cases of aortobifemoral bypass graft malposition through the colon. Case 1 is a 54-year-old male who underwent aortobifemoral bypass grafting for acute limb ischemia. He had previously undergone a partial sigmoid colectomy for diverticulitis. Approximately 6 months after vascular surgery, he presented with an occult graft infection. Preoperative imaging and intraoperative findings were consistent with graft placement through the sigmoid colon. Case 2 is a 60-year-old male who underwent aortobifemoral bypass grafting due to a nonhealing wound after toe amputation. His postoperative course was complicated by pneumonia, bacteremia thought to be secondary to the pneumonia, general malaise, and persistent fevers. Approximately 10 weeks after the vascular surgery, he presented with imaging and intraoperative findings of graft malposition through the cecum. Aortic graft infection is usually caused by surgical contamination and presents as an indolent infection. Case 1 presented as such; Case 2 presented more acutely. Both grafts were iatrogenically misplaced through the colon at the index operation. The patients underwent extra-anatomic bypass and graft explantation and subsequently recovered.

  16. The Diffusion Coefficients Of Cu And Zn In amp913- And amp919- Solid Solutions

    Directory of Open Access Journals (Sweden)

    Adhurim Hoxha

    2015-06-01

    Full Text Available Abstract In this work the multiphase diffusion in the infinite couple Cu-Zn was studied experimentally. The diffusion couples were prepared by platting technique. The samples were annealed in three different temperatures which were taken below the melting temperature of Zn. For each temperature there were used six different annealing times ranging from 1h up to 32h. In the micrographs provided by light microscopy it can be seen the formation of only two of the three intermetalic phases present in the Cu-Zn phase diagram namely amp949- and amp947-phase. WDX EPMA analysis was used to obtain the concentration profiles of the diffusion layers.he diffusion coefficients of Cu and Zn in amp945- and amp951-solid solutions are calculated using the solutions of second Ficks law for independent concentration case. Since the diffusion coefficients depends only on the temperature of annealing and not on the time of it they must be the same for a given temperature. Therefore the diffusion coefficients were averaged for each temperature. Knowing the diffusion coefficients for each temperature enables the calculation of the activation energies and the frequency factors as well.

  17. A derivative of ascorbic acid modulates cAMP production.

    Science.gov (United States)

    Bordignon, B; Mones, S; Rahman, F; Chiron, J; Peiretti, F; Vidal, N; Fontes, M

    2013-09-13

    We reported, in previous experiments, that AA is a global regulator of cAMP pools. In this study, we demonstrate that K873, an analog of AA we synthesized and presenting antiproliferative properties, has also an impact on cAMP production. However, K873 has no antioxidant activity, at the contrary of AA. It definitively demonstrates that action of AA on the cAMP production is not linked to antioxidant activity. These data suggest that AA, and derivatives of this molecule, could be promising drug acting on biological processes that are under the control of cAMP dependent pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. S-AMP for non-linear observation models

    DEFF Research Database (Denmark)

    Cakmak, Burak; Winther, Ole; Fleury, Bernard H.

    2015-01-01

    matrix has zero-mean iid Gaussian entries. Our derivation is based upon 1) deriving expectation-propagation-(EP)-like equations from the stationary-points equations of the Gibbs free energy under first- and second-moment constraints and 2) applying additive free convolution in free probability theory......Recently we presented the S-AMP approach, an extension of approximate message passing (AMP), to be able to handle general invariant matrix ensembles. In this contribution we extend S-AMP to non-linear observation models. We obtain generalized AMP (GAMP) as the special case when the measurement...

  19. Internal gastargets in AmPS

    Science.gov (United States)

    Kaan, A. P.; Postma, O.; van den Brand, J. F. J.; van Leeuwen, E.; Doets, M.; Kraan, M.

    1997-05-01

    Internal gas targets in AmPS A.P. Kaan, O. Postma, J.F.J. van den Brand, E. van Leeuwen, M. Doets, M. Kra= an National Institute for Nuclear Physics and High Energy Physics; Kruislaan 409; 1098 SJ Amsterdam; Holland In the Amsterdam Puls Stretcher/storage ring AmPS(1 GeV electrons), we designed a set-up in order to accommodate a gas target with a density of 1016 mol/cm2. The storage cell needed for this purpose is a aluminium tube with a length of 40 cm, a diameter of 15 mm and a wall thickness of 25 =B5m. Three sets of conductance limiters on both sides of the target, combined with dry turbopumps are designed to be used as differential pumping stations. These limiters cause discontinuities in the beam path and must therefor be retractable and radio frequency compatible in both positions. Low =B5 materials must be used because of the depolarisation effects of changing magnetic fields. The calculations show that the flow resistance's are sufficient to reduce the load of the getter pumps to a level with which the lifetime of the pump elements remain acceptable. The design of the mechanics and the vacuum system will be explained. Recent results from the measurements after installation in combination with the influence on the lifetime on the beam will be presented

  20. Prolongation of allograft survival by 1,25-dihydroxyvitamin D3.

    Science.gov (United States)

    Hullett, D A; Cantorna, M T; Redaelli, C; Humpal-Winter, J; Hayes, C E; Sollinger, H W; Deluca, H F

    1998-10-15

    1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection.

  1. CMR diagnosis of coronary graft fistula

    Directory of Open Access Journals (Sweden)

    Bengt Johansson

    2014-01-01

    Full Text Available The patient is a 54-year old man with a previous history of cerebral aqueduct stenosis and hydrocephalus resulting in malignant hypertension who had surgery for permanent ventriculo-peritoneal shunt. At age 41, he had coronary artery bypass graft (CABG surgery with the right internal mammary artery anastomosed to the posterior descending artery and a saphenous vein graft to the first obtuse marginal branch. The patient was recently admitted with pneumonia that rapidly deteriorated and he went in respiratory failure requiring mechanical ventilation. A thoracic CT investigation showed massive bilateral pulmonary infiltrates, pulmonary artery embolism and a large vein graft aneurysm with a maximal diameter of 40 mm (Figure 1 A-B. The management course was complicated with prolonged respiratory failure, persistent infection, despite negative cultures and extended hospital stay. After 50 days of slow recovery the patient was discharged with a need for home oxygen therapy. Ten days later, he was re-admitted with chest pain requiring admission to the coronary care unit where severe pulmonary hypertension was diagnosed with Doppler echocardiography. Troponin-T was mildly elevated, 1,3 ug/L (ref <0,01, CRP was 50 mg/L and chest X-ray showed bilateral lung infiltrates and wide pulmonary vessels. At this point a systo-diastolic murmur was heard at the left lower sternal edge. With a view of potential coronary reintervention and to evaluate the pulmonary hypertension, a coronary angiogram and a pulmonary artery cathetherisation were performed. This showed a new stenosis in the left anterior descending coronary artery and the pulmonary catheterisation showed a “step-up” in oxygen saturation in the pulmonary artery, suggesting a left-to-right shunt. The vein graft aneurysm did not contribute to the coronary circulation. A cardiovascular magnetic resonance scan revealed a communication between the vein graft aneurysm and the left branch pulmonary artery

  2. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, L; Martinussen, J; Møllegaard, N E

    1990-01-01

    We have investigated the regulation of the Escherichia coli deoCp2 promoter by the CytR repressor and the cyclic AMP (cAMP) receptor protein (CRP) complexed to cAMP. Promoter regions controlled by these two proteins characteristically contain tandem cAMP-CRP binding sites. Here we show that (i) Cyt...

  3. Periorbital fat grafting.

    Science.gov (United States)

    Massry, Guy G; Azizzadeh, Babak

    2013-02-01

    Periorbital aging is a multifactorial process involving volume loss (bone and soft tissue), tissue decent, and cutaneous degenerative changes. Traditional approaches to surgery on this area of the face have been subtractive in nature, focusing on excision of skin, muscle, and fat. This has frequently led to a gaunt or hollowed postoperative appearance. Contemporary aesthetic eyelid and periorbital rejuvenation has undergone a paradigm shift from an excisionally based surgical approach to one that prioritizes volume preservation and/or augmentation. The development of fat grafting to the eyelids and periorbita has given the eyelid surgeon a viable surgical alternative to prevent postoperative volume depletion, maintain the smooth transition of the lower eyelid to the cheek, and aid in restoring the youthful appearance desired after surgery. This article will focus of periorbital fat grafting and touch upon fat preservation techniques as primary restorative procedures or as surgical adjuncts. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Vein grafting in fingertip replantations.

    Science.gov (United States)

    Yan, Hede; Jackson, William D; Songcharoen, Somjade; Akdemir, Ovunc; Li, Zhijie; Chen, Xinglong; Jiang, Liangfu; Gao, Weiyang

    2009-01-01

    In this retrospective study, the survival rates of fingertip replantation with and without vein grafting were evaluated along with their postoperative functional and cosmetic results. One hundred twenty-one-fingertip amputations were performed in 103 patients between September 2002 and July 2007. Thirty-four amputated fingertips were replanted without vein grafting, while 87 amputated fingertips were replanted with vein grafting for arterial and/or venous repairs. The overall survival rates of the replantations with and without vein grafting were 90% (78/87) and 85% (29/34), respectively. The survival rates were 88% (36/41) with venous repair, 93% (25/27) with arterial repair, and 89% (17/19) with both. Nineteen patients without vein grafting and 48 patients with vein grafting had a follow-up period of more than one year. Good cosmetic and functional outcomes were observed in both groups of patients. The results show that vein grafting is a reliable technique in fingertip replantations, showing no significant difference (P > 0.05) in survival between those with and without vein grafting. Furthermore, no significant difference (P > 0.05) in survival was found between cases with vein grafts for arterial and/or venous repairs. In fingertip replantations with vein grafting, favorable functional and esthetic results can be achieved without sacrificing replantation survival. (c) 2009 Wiley-Liss, Inc.

  5. Morphology and function of dog arterial grafts preserved in UW-solution

    NARCIS (Netherlands)

    Vischjager, M.; van Gulik, T. M.; Pfaffendorf, M.; van Zwieten, P. A.; van Marle, J.; Kromhout, J. G.; Klopper, P. J.; Jacobs, M. J.

    1995-01-01

    To assess the function of arterial grafts after prolonged preservation in the University of Wisconsin solution (UW), in vitro and in vivo. Carotid arteries were harvested from dogs and stored for 1-21 days at 4 degrees C in UW (n = 10) or in PBS (0.9% NaCl, pH 7.4), (PBS) (n = 10). Slices were

  6. Cyclic AMP (cAMP)-mediated stimulation of adipocyte differentiation requires the synergistic action of Epac- and cAMP-dependent protein kinase-dependent processes

    DEFF Research Database (Denmark)

    Petersen, Rasmus Koefoed; Madsen, Lise; Pedersen, Lone Møller

    2008-01-01

    AMP-dependent stimulation of adipocyte differentiation. Epac, working via Rap, acted synergistically with cAMP-dependent protein kinase (protein kinase A [PKA]) to promote adipogenesis. The major role of PKA was to down-regulate Rho and Rho-kinase activity, rather than to enhance CREB phosphorylation. Suppression of Rho......-kinase impaired proadipogenic insulin/insulin-like growth factor 1 signaling, which was restored by activation of Epac. This interplay between PKA and Epac-mediated processes not only provides novel insight into the initiation and tuning of adipocyte differentiation, but also demonstrates a new mechanism of c......AMP signaling whereby cAMP uses both PKA and Epac to achieve an appropriate cellular response....

  7. MEK Inhibitors Reverse cAMP-Mediated Anxiety in Zebrafish

    DEFF Research Database (Denmark)

    Lundegaard, Pia R.; Anastasaki, Corina; Grant, Nicola J.

    2015-01-01

    Altered phosphodiesterase (PDE)-cyclic AMP (cAMP) activity is frequently associated with anxiety disorders, but current therapies act by reducing neuronal excitability rather than targeting PDE-cAMP-mediated signaling pathways. Here, we report the novel repositioning of anti-cancer MEK inhibitors...... as anxiolytics in a zebrafish model of anxiety-like behaviors. PDE inhibitors or activators of adenylate cyclase cause behaviors consistent with anxiety in larvae and adult zebrafish. Small-molecule screening identifies MEK inhibitors as potent suppressors of cAMP anxiety behaviors in both larvae and adult...... zebrafish, while causing no anxiolytic behavioral effects on their own. The mechanism underlying cAMP-induced anxiety is via crosstalk to activation of the RAS-MAPK signaling pathway. We propose that targeting crosstalk signaling pathways can be an effective strategy for mental health disorders, and advance...

  8. Selective adsorption properties of Cs for mordenite enclosing Amp microcapsules

    Energy Technology Data Exchange (ETDEWEB)

    Mimura, Hitoshi; Kanome, Shun; Kato, Mariko; Niibori, Yuichi [Tohoku Univ., Sendai (Japan)

    2012-03-15

    Selective separation and recovery of heat-generating nuclide ({sup 137}Cs) from high-level liquid waste (HLLW) containing highly concentrated HNO{sub 3} and NaNO{sub 3} are vital issues in relation to the partitioning of radionuclides and volume reduction of radioactive wastes. This paper deals with the novel preparation method of Cs-selective adsorbents. Amp-M, kind of inorganic and organic composites, was prepared by successive impregnation of Pma (H{sub 3}Mo{sub 12}O{sub 40}P) and kneaded sol (NH{sub 4}NO{sub 3} and sodium alginate (NALGO) into the macro pores of mordenite. Amp-M composites obtained by 1 to 3 cycles were abbreviated as Amp-M1, Amp-M2 and Amp-M3, respectively.

  9. Synergistic Antipseudomonal Effects of Synthetic Peptide AMP38 and Carbapenems.

    Science.gov (United States)

    Rudilla, Héctor; Fusté, Ester; Cajal, Yolanda; Rabanal, Francesc; Vinuesa, Teresa; Viñas, Miguel

    2016-09-12

    The aim was to explore the antimicrobial activity of a synthetic peptide (AMP38) and its synergy with imipenem against imipenem-resistant Pseudomonas aeruginosa. The main mechanism of imipenem resistance is the loss or alteration of protein OprD. Time-kill and minimal biofilm eradication concentration (MBEC) determinations were carried out by using clinical imipenem-resistant strains. AMP38 was markedly synergistic with imipenem when determined in imipenem-resistant P. aeruginosa. MBEC obtained for the combination of AMP38 and imipenem was of 62.5 μg/mL, whereas the MBEC of each antimicrobial separately was 500 μg/mL. AMP38 should be regarded as a promising antimicrobial to fight MDR P. aeruginosa infections. Moreover, killing effect and antibiofilm activity of AMP38 plus imipenem was much higher than that of colistin plus imipenem.

  10. Outcomes of coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Anna Louise Hawkes

    2006-12-01

    Full Text Available Anna Louise Hawkes1,3, Madeleine Nowak1, Benjamin Bidstrup2, Richard Speare11School of Public Health, Tropical, Medicine and Rehabilitation Sciences, James Cook University, Townsville, Queensland, Australia (3Currently Queensland Cancer Fund; 2John Flynn Hospital, Gold Coast, Queensland, AustraliaAbstract: This review article summarizes the major studies that have investigated the outcomes of coronary artery bypass graft surgery (CABG. The article includes a review of the literature in the areas of: history of CABG; indications for CABG; and measurement of quality of life following CABG, including prolongation of life, physical functioning (ie, relief from angina and dyspnea, physical activity, as well as complications of surgery and re-hospitalization, psychological functioning, and social functioning. Overall, the literature demonstrates that the outcomes of CABG have historically been measured in terms of mortality and morbidity; however, it has now been well recognized that adjustment to CABG is a multidimensional phenomenon that is not fully explained by medical factors. Therefore, in addition to studying mortality and morbidity outcomes following CABG, many recent studies have identified that it is important to investigate various physical, psychological, and social variables that have a significant impact on post-operative adjustment to CABG. Keywords: coronary artery bypass graft surgery, outcomes, quality of life, recovery

  11. Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

    Science.gov (United States)

    Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

    2017-08-17

    Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

  12. Using skeletonised grafts for coronary artery bypass grafting.

    Science.gov (United States)

    Bawany, Faizan Imran; Khan, Muhammad Shahzeb; Khan, Asadullah; Kazi, Abdul Nafey; Naeem, Muhammed

    2014-05-01

    Coronary artery bypass graft surgery relieves angina symptoms and reduces mortality among ischaemic heart disease patients. It remains the gold standard for the treatment of multi-vessel and left main coronary artery disease. It is a well-known fact that internal mammary artery conduits have excellent and long-lasting patency when used for coronary artery bypass grafting. Its supremacy is largely because it prevents atherosclerosis. The old-style internal mammary artery bypass grafting, classically known as pedicle grafting, includes a circular rim of tissue around the graft. Bilateral pedicled internal mammary arteries, especially among diabetic patients, have been reported to cause complications in the sternum like sternal osteomyelitis. In many studies it has been reported that dissection of pedicled internal mammary artery can lead to sternal devascularisation which can lead to higher incidence of infections. Considering the higher incidence of deep sternal infections in patients with double pedicled arterial grafts, dissection of internal mammary artery in skeletonised manner was proposed. In this review, we outline the advantages of skeletonised grafting with respect to incidence of sternal infection, patency rates, blood flow, post-coronary artery bypass graft pain and the length of the graft.

  13. Development of a water purifier for radioactive cesium removal from contaminated natural water by radiation-induced graft polymerization

    Science.gov (United States)

    Seko, Noriaki; Hoshina, Hiroyuki; Kasai, Noboru; Shibata, Takuya; Saiki, Seiichi; Ueki, Yuji

    2018-02-01

    Six years after the Fukushima-nuclear accident, the dissolved radioactive cesium (Cs) is now hardly detected in environmental natural waters. These natural waters are directly used as source of drinking and domestic waters in disaster-stricken areas in Fukushima. However, the possibility that some radioactive Cs adsorbed on soil or leaves will contaminate these natural waters during heavy rains or typhoon is always present. In order for the returning residents to live with peace of mind, it is important to demonstrate the safety of the domestic waters that they will use for their daily life. For this purpose, we have synthesized a material for selective removal of radioactive Cs by introducing ammonium 12-molybdophosphate (AMP) onto polyethylene nonwoven fabric through radiation-induced emulsion graft polymerization technique. Water purifiers filled with the grafted Cs adsorbent were installed in selected houses in Fukushima. The capability of the grafted adsorbent to remove Cs from domestic waters was evaluated for a whole year. The results showed that the tap water filtered through the developed water purifier contained no radioactive Cs, signifying the very effective adsorption performance of the developed grafted adsorbent. From several demonstrations, we have commercialized the water purifier named "KranCsair®". Furthermore, we have also developed a method for the mass production of the grafted nonwoven fabric. Using a 30 L grafting reactor, it was possible to produce the grafted nonwoven fabric with a suitable range of degree of grafting. When an irradiated roll of nonwoven trunk fabric with a length of 10 m and a width of 30 cm was set in the reactor filled with glycidyl methacrylate (GMA), AMP, Tween 80 monomer emulsion solution at 40 °C for 1 h, the difference of Dgs in the length and the width on roll of fabrics was negligible.

  14. Micrografts: the "super" expansion graft.

    Science.gov (United States)

    Mardovin, W; Miller, S F; Eppinger, M; Finley, R K

    1992-01-01

    A novel technique for producing micronized skin grafts that was introduced in a paper presented at the 1990 ABA meeting was evaluated to quantify maximum expansion. Twenty Sprague-Dawley rats were divided into two groups representing 10:1 and 25:1 expanded micrograft ratios, respectively. Grafted sites in both groups were shown to heal better than those of the control group, and both grafted groups showed comparable healing at day 10.

  15. Environmental application of radiation grafting

    International Nuclear Information System (INIS)

    Tamada, Masao

    2007-01-01

    Adsorbent having high selectivity against a certain metal ion was synthesized by means of radiation-induced graft polymerization for the purpose of environmental application. The resulting adsorbents were utilized for the removal of toxic metal from scallop waste and the collection of uranium from seawater. As a novel application of grafting, the biodegradability of poly-hydroxybutylate was controlled by grafting. The biodegradability could be depressed by the graft chain and then recovered by external stimuli such as thermal and chemical treatments. (author)

  16. Sleep deprivation impairs cAMP signalling in the hippocampus.

    Science.gov (United States)

    Vecsey, Christopher G; Baillie, George S; Jaganath, Devan; Havekes, Robbert; Daniels, Andrew; Wimmer, Mathieu; Huang, Ted; Brown, Kim M; Li, Xiang-Yao; Descalzi, Giannina; Kim, Susan S; Chen, Tao; Shang, Yu-Ze; Zhuo, Min; Houslay, Miles D; Abel, Ted

    2009-10-22

    Millions of people regularly obtain insufficient sleep. Given the effect of sleep deprivation on our lives, understanding the cellular and molecular pathways affected by sleep deprivation is clearly of social and clinical importance. One of the major effects of sleep deprivation on the brain is to produce memory deficits in learning models that are dependent on the hippocampus. Here we have identified a molecular mechanism by which brief sleep deprivation alters hippocampal function. Sleep deprivation selectively impaired 3', 5'-cyclic AMP (cAMP)- and protein kinase A (PKA)-dependent forms of synaptic plasticity in the mouse hippocampus, reduced cAMP signalling, and increased activity and protein levels of phosphodiesterase 4 (PDE4), an enzyme that degrades cAMP. Treatment of mice with phosphodiesterase inhibitors rescued the sleep-deprivation-induced deficits in cAMP signalling, synaptic plasticity and hippocampus-dependent memory. These findings demonstrate that brief sleep deprivation disrupts hippocampal function by interfering with cAMP signalling through increased PDE4 activity. Thus, drugs that enhance cAMP signalling may provide a new therapeutic approach to counteract the cognitive effects of sleep deprivation.

  17. Suction blister grafting - Modifications for easy harvesting and grafting

    Directory of Open Access Journals (Sweden)

    2012-01-01

    Full Text Available Suction blister grafting is a simple modality of treatment of patients with resistant and stable vitiligo. But raising the blisters may be time consuming and transferring to the recipient site may be difficult as the graft is ultrathin. By doing some modifications we can make the technique simpler and easier. We can decrease the blister induction time by intradermal injection of saline, exposure to Wood′s lamp, intrablister injection of saline. By these methods we can decrease the blister induction time from 2-3 hrs to 45-90 minutes. After harvesting the graft, it can be transferred to the recipient area by taking the graft on a sterile glass slide, on the gloved finger, rolling the graft over a sterile syringe and then spreading on the recipient area, or taking on the sterile wrapper of paraffin dressing and then placing over the recipient area.

  18. Imaging alterations of cardiomyocyte cAMP microdomains in disease

    Directory of Open Access Journals (Sweden)

    Alexander eFroese

    2015-08-01

    Full Text Available 3’,5’-cyclic adenosine monophosphate (cAMP is an important second messenger which regulates heart function by acting in distinct subcellular microdomains. Recent years have provided deeper mechanistic insights into compartmentalized cAMP signaling and its link to cardiac disease. In this mini review, we summarize newest developments in this field achieved by cutting-edge biochemical and biophysical techniques. We further compile the data from different studies into a bigger picture of so far uncovered alterations in cardiomyocyte cAMP microdomains which occur in compensated cardiac hypertrophy and chronic heart failure. Finally, future research directions and translational perspectives are briefly discussed.

  19. Prolonged Intermittent Renal Replacement Therapy.

    Science.gov (United States)

    Edrees, Fahad; Li, Tingting; Vijayan, Anitha

    2016-05-01

    Prolonged intermittent renal replacement therapy (PIRRT) is becoming an increasingly popular alternative to continuous renal replacement therapy in critically ill patients with acute kidney injury. There are significant practice variations in the provision of PIRRT across institutions, with respect to prescription, technology, and delivery of therapy. Clinical trials have generally demonstrated that PIRRT is non-inferior to continuous renal replacement therapy regarding patient outcomes. PIRRT offers cost-effective renal replacement therapy along with other advantages such as early patient mobilization and decreased nursing time. However, due to lack of standardization of the procedure, PIRRT still poses significant challenges, especially pertaining to appropriate drug dosing. Future guidelines and clinical trials should work toward developing consensus definitions for PIRRT and ensure optimal delivery of therapy. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  20. Bone grafting options in children.

    Science.gov (United States)

    Betz, Randal R; Lavelle, William F; Samdani, Amer F

    2010-08-01

    Retrospective review of the literature. To review the current literature as well as recent trends in bone grafting techniques available for children. The currently accepted gold standard in bone grafting for adolescent idiopathic scoliosis (AIS) is autogenous iliac crest. Due to questions concerning complications such as donor site pain, other options have been explored, including various allograft sources, demineralized bone matrix, and bone morphogenetic protein. A review of the current medical literature was completed and additional case examples are presented. A review of the literature reveals that up to 31% of patients have persistent pain at 2 years post surgery when autogenous iliac crest bone graft is harvested. Allograft supplementation of local autograft has been demonstrated in the literature to be as effective as autogenous iliac crest bone grafting in contributing to a successful posterior spinal fusion in patients with AIS. Modern demineralized bone matrix formulations have been found in both animal models as well as in a recent retrospective clinical review to contribute to a successful posterior spinal fusion in AIS. Bone morphogenetic protein has been shown to contribute to a successful posterior spinal fusion in complex pediatric spinal deformity patients. At 2 years follow-up, patients who underwent a posterior instrumented spinal fusion that was not augmented with any bone graft appear to have successful spinal fusions. Although autogenous iliac bone graft remains the benchmark to which bone grafting materials are compared, other options including the placement of no bone graft at all provides similar fusion rates in patients with AIS.

  1. Amped Up! - Volume 1, No. 3, May/June 2015

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-05-01

    Welcome to the latest issue of our bimonthly newsletter, Amped Up!, highlighting the initiatives, events and technologies in the Office of Energy Efficiency and Renewable Energy that influence change.

  2. Cardiac cAMP: production, hydrolysis, modulation and detection

    Directory of Open Access Journals (Sweden)

    Cédric eBOULARAN

    2015-10-01

    Full Text Available Cyclic adenosine 3’,5’-monophosphate (cAMP modulates a broad range of biological processes including the regulation of cardiac myocyte contractile function where it constitutes the main second messenger for β-adrenergic receptors’ signaling to fulfill positive chronotropic, inotropic and lusitropic effects. A growing number of studies pinpoint the role of spatial organization of the cAMP signaling as an essential mechanism to regulate cAMP outcomes in cardiac physiology. Here, we will briefly discuss the complexity of cAMP synthesis and degradation in the cardiac context, describe the way to detect it and review the main pharmacological arsenal to modulate its availability.

  3. Radiation grafting on natural films

    Science.gov (United States)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  4. Microgravity changes in heart structure and cyclic-AMP metabolism

    Science.gov (United States)

    Philpott, D. E.; Fine, A.; Kato, K.; Egnor, R.; Cheng, L.

    1985-01-01

    The effects of microgravity on cardiac ultrastructure and cyclic AMP metabolism in tissues of rats flown on Spacelab 3 are reported. Light and electron microscope studies of cell structure, measurements of low and high Km phosphodiesterase activity, cyclic AMP-dependent protein kinase activity, and regulatory subunit compartmentation show significant deviations in flight animals when compared to ground controls. The results indicate that some changes have occurred in cellular responses associated with catecholamine receptor interactions and intracellular signal processing.

  5. Effects of electron beam irradiation on inorganic exchanger AMP

    International Nuclear Information System (INIS)

    Rao, K.L.N.; Mathew, C.; Deshpande, R.S.; Jadhav, A.V.; Pande, B.M.; Shukla, J.P.

    1996-01-01

    The heteropolyacid salt inorganic exchanger ammonium molybdophosphate (AMP) was subjected to an electron dose upto 2 MGy to assess any possible radiation damage. The breakthrough and total exchange capacity of AMP for Cs + from simulated fission product solutions were determined for both control and irradiated samples. The scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX) were deployed to examine any marked microscopic changes taking place in this exchanger. (author). 3 refs., 3 figs

  6. Covalent immobilization of antimicrobial peptides (AMPs) onto biomaterial surfaces.

    Science.gov (United States)

    Costa, Fabíola; Carvalho, Isabel F; Montelaro, Ronald C; Gomes, P; Martins, M Cristina L

    2011-04-01

    Bacterial adhesion to biomaterials remains a major problem in the medical devices field. Antimicrobial peptides (AMPs) are well-known components of the innate immune system that can be applied to overcome biofilm-associated infections. Their relevance has been increasing as a practical alternative to conventional antibiotics, which are declining in effectiveness. The recent interest focused on these peptides can be explained by a group of special features, including a wide spectrum of activity, high efficacy at very low concentrations, target specificity, anti-endotoxin activity, synergistic action with classical antibiotics, and low propensity for developing resistance. Therefore, the development of an antimicrobial coating with such properties would be worthwhile. The immobilization of AMPs onto a biomaterial surface has further advantages as it also helps to circumvent AMPs' potential limitations, such as short half-life and cytotoxicity associated with higher concentrations of soluble peptides. The studies discussed in the current review report on the impact of covalent immobilization of AMPs onto surfaces through different chemical coupling strategies, length of spacers, and peptide orientation and concentration. The overall results suggest that immobilized AMPs may be effective in the prevention of biofilm formation by reduction of microorganism survival post-contact with the coated biomaterial. Minimal cytotoxicity and long-term stability profiles were obtained by optimizing immobilization parameters, indicating a promising potential for the use of immobilized AMPs in clinical applications. On the other hand, the effects of tethering on mechanisms of action of AMPs have not yet been fully elucidated. Therefore, further studies are recommended to explore the real potential of immobilized AMPs in health applications as antimicrobial coatings of medical devices. Copyright © 2010 Acta Materialia Inc. All rights reserved.

  7. Cigarette smoke activates CFTR through ROS-stimulated cAMP signaling in human bronchial epithelial cells.

    Science.gov (United States)

    Wong, Francis H; AbuArish, Asmahan; Matthes, Elizabeth; Turner, Mark J; Greene, Lana E; Cloutier, Alexandre; Robert, Renaud; Thomas, David Y; Cosa, Gonzalo; Cantin, André M; Hanrahan, John W

    2018-01-01

    Air pollution stimulates airway epithelial secretion through a cholinergic reflex that is unaffected in cystic fibrosis (CF), yet a strong correlation is observed between passive smoke exposure in the home and impaired lung function in CF children. Our aim was to study the effects of low smoke concentrations on cystic fibrosis transmembrane conductance regulator (CFTR) function in vitro. Cigarette smoke extract stimulated robust anion secretion that was transient, mediated by CFTR, and dependent on cAMP-dependent protein kinase activation. Secretion was initiated by reactive oxygen species (ROS) and mediated by at least two distinct pathways: autocrine activation of EP4 prostanoid receptors and stimulation of Ca 2+ store-operated cAMP signaling. The response was absent in cells expressing the most common disease-causing mutant F508del-CFTR. In addition to the initial secretion, prolonged exposure of non-CF bronchial epithelial cells to low levels of smoke also caused a gradual decline in CFTR functional expression. F508del-CFTR channels that had been rescued by the CF drug combination VX-809 (lumacaftor) + VX-770 (ivacaftor) were more sensitive to this downregulation than wild-type CFTR. The results suggest that CFTR-mediated secretion during acute cigarette smoke exposure initially protects the airway epithelium while prolonged exposure reduces CFTR functional expression and reduces the efficacy of CF drugs.

  8. Prolonged QT interval in Rett syndrome

    OpenAIRE

    Ellaway, C; Sholler, G; Leonard, H; Christodoulou, J

    1999-01-01

    Rett syndrome is a severe neurodevelopmental disorder of unknown aetiology. A prolonged QT interval has been described previously in patients with Rett syndrome. To investigate QT prolongation and the presence of cardiac tachyarrhythmias in Rett syndrome electrocardiography and 24 hour Holter monitoring were performed prospectively in a cohort of 34 girls with Rett syndrome. The corrected QT value was prolonged in nine patients. Compared with a group of healthy controls of a...

  9. Graft intolerance syndrome requiring graft nephrectomy after late kidney graft failure: can it be predicted? A retrospective cohort study.

    Science.gov (United States)

    Bunthof, Kim L W; Verhoeks, Carmen M; van den Brand, Jan A J G; Hilbrands, Luuk B

    2018-02-01

    Graft nephrectomy is recommended in case of early graft failure. When the graft fails more than 3-6 months after transplantation, it is current practice to follow a wait-and-see policy. A common indication for graft removal is the graft intolerance syndrome. We aimed to create a risk prediction model for the occurrence of graft intolerance resulting in graft nephrectomy. We collected data of kidney transplantations performed in our center between 1980 and 2010 that failed at least 6 months after transplantation. We evaluated the association between baseline characteristics and the occurrence of graft nephrectomy because of graft intolerance using a competing risk regression model. Prognostic factors were included in a multivariate prediction model. In- and exclusion criteria were met in 288 cases. In 48 patients, the graft was removed because of graft intolerance. Donor age, the number of rejections, and shorter graft survival were predictive factors for graft nephrectomy because of the graft intolerance syndrome. These factors were included in a prediction rule. Using donor age, graft survival, and the number of rejections, clinicians can predict the need for graft nephrectomy with a reasonable accuracy. © 2017 Steunstichting ESOT.

  10. 2',3'-cAMP, 3'-AMP, 2'-AMP and adenosine inhibit TNF-α and CXCL10 production from activated primary murine microglia via A2A receptors.

    Science.gov (United States)

    Newell, Elizabeth A; Exo, Jennifer L; Verrier, Jonathan D; Jackson, Travis C; Gillespie, Delbert G; Janesko-Feldman, Keri; Kochanek, Patrick M; Jackson, Edwin K

    2015-01-12

    Some cells, tissues and organs release 2',3'-cAMP (a positional isomer of 3',5'-cAMP) and convert extracellular 2',3'-cAMP to 2'-AMP plus 3'-AMP and convert these AMPs to adenosine (called the extracellular 2',3'-cAMP-adenosine pathway). Recent studies show that microglia have an extracellular 2',3'-cAMP-adenosine pathway. The goal of the present study was to investigate whether the extracellular 2',3'-cAMP-adenosine pathway could have functional consequences on the production of cytokines/chemokines by activated microglia. Experiments were conducted in cultures of primary murine microglia. In the first experiment, the effect of 2',3'-cAMP, 3'-AMP, 2'-AMP and adenosine on LPS-induced TNF-α and CXCL10 production was determined. In the next experiment, the first protocol was replicated but with the addition of 1,3-dipropyl-8-p-sulfophenylxanthine (DPSPX) (0.1 μM; antagonist of adenosine receptors). The last experiment compared the ability of 2-chloro-N(6)-cyclopentyladenosine (CCPA) (10 μM; selective A1 agonist), 5'-N-ethylcarboxamide adenosine (NECA) (10 μM; agonist for all adenosine receptor subtypes) and CGS21680 (10 μM; selective A2A agonist) to inhibit LPS-induced TNF-α and CXCL10 production. (1) 2',3'-cAMP, 3'-AMP, 2'-AMP and adenosine similarly inhibited LPS-induced TNF-α and CXCL10 production; (2) DPSPX nearly eliminated the inhibitory effects of 2',3'-cAMP, 3'-AMP, 2'-AMP and adenosine on LPS-induced TNF-α and CXCL10 production; (3) CCPA did not affect LPS-induced TNF-α and CXCL10; (4) NECA and CGS21680 similarly inhibited LPS-induced TNF-α and CXCL10 production. 2',3'-cAMP and its metabolites (3'-AMP, 2'-AMP and adenosine) inhibit LPS-induced TNF-α and CXCL10 production via A2A-receptor activation. Adenosine and its precursors, via A2A receptors, likely suppress TNF-α and CXCL10 production by activated microglia in brain diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. 2’,3’-cAMP, 3’-AMP, 2’-AMP and Adenosine Inhibit TNF-α and CXCL10 Production From Activated Primary Murine Microglia via A2A Receptors

    Science.gov (United States)

    Newell, Elizabeth A.; Exo, Jennifer L.; Verrier, Jonathan D.; Jackson, Travis C.; Gillespie, Delbert G.; Janesko-Feldman, Keri; Kochanek, Patrick M.

    2014-01-01

    Background Some cells, tissues and organs release 2’,3’-cAMP (a positional isomer of 3’,5’-cAMP) and convert extracellular 2’,3’-cAMP to 2’-AMP plus 3’-AMP and convert these AMPs to adenosine (called the extracellular 2’,3’-cAMP-adenosine pathway). Recent studies show that microglia have an extracellular 2’,3’-cAMP-adenosine pathway. The goal of the present study was to investigate whether the extracellular 2’,3’-cAMP-adenosine pathway could have functional consequences on the production of cytokines/chemokines by activated microglia. Methods Experiments were conducted in cultures of primary murine microglia. In the first experiment, the effect of 2’,3’-cAMP, 3’-AMP, 2’-AMP and adenosine on LPS-induced TNF-α and CXCL10 production was determined. In the next experiment, the first protocol was replicated but with the addition of 1,3-dipropyl-8-p-sulfophenylxanthine (DPSPX) (0.1 µM; antagonist of adenosine receptors). The last experiment compared the ability of 2-chloro-N6-cyclopentyladenosine (CCPA) (10 µM; selective A1 agonist), 5’-N-ethylcarboxamide adenosine (NECA) (10 µM; agonist for all adenosine receptor subtypes) and CGS21680 (10 µM; selective A2A agonist) to inhibit LPS-induced TNF-α and CXCL10 production. Results 1) 2’,3’-cAMP, 3’-AMP, 2’-AMP and adenosine similarly inhibited LPS-induced TNF-α and CXCL10 production; 2) DPSPX nearly eliminated the inhibitory effects of 2’,3’-cAMP, 3’-AMP, 2’-AMP and adenosine on LPS-induced TNF-α and CXCL10 production; 3) CCPA did not affect LPS-induced TNF-α and CXCL10; 4) NECA and CGS21680 similarly inhibited LPS-induced TNF-α and CXCL10 production. Conclusions 2’,3’-cAMP and its metabolites (3’-AMP, 2’-AMP and adenosine) inhibit LPS-induced TNF-α and CXCL10 production via A2A-receptor activation. Adenosine and its precursors, via A2A receptors, likely suppress TNF-α and CXCL10 production by activated microglia in brain diseases. PMID:25451117

  12. Prolongation of rat heart allografts by donor-specific blood transfusion treated with ultraviolet irradiation

    International Nuclear Information System (INIS)

    Oluwole, S.F.; Iga, C.; Lau, H.; Hardy, M.A.

    1985-01-01

    The effect of donor-specific blood transfusion was compared to that of UVB-irradiated donor-specific blood transfusion on heart allograft survival in inbred rats with major histocompatibility differences. In one series ACI rats received heterotopic heart grafts from Lewis rats and 1 mL transfusion of donor-type blood at 1, 2, and 3 weeks prior to the transplantation. Fifty percent of the grafts were permanently accepted (survival greater than 200 days). Following UVB-irradiated donor-specific blood transfusion, 55% of the grafts survived indefinitely. In a mixed lymphocyte reaction ACI lymphocytes are weak responders to Lewis lymphocytes. In another series, Lewis rats received ACI hearts. Donor-specific transfusions at 1, 2, and 3 weeks prior to transplantation did not significantly alter the survival of heart allografts. Lewis lymphocytes react strongly to ACI stimulator cells in a mixed lymphocyte reaction. However, when the donor blood was UVB-irradiated prior to transfusion, the ACI allograft survival was significantly prolonged in this ACI-to-Lewis strain combination. When Lewis rats received W/F hearts following either donor-specific or UVB-irradiated donor-specific transfusions, the hearts' survival was similarly and significantly prolonged, but did not become permanent. Mixed lymphocyte reaction reveals that the stimulation index of Lewis lymphocytes against W/F lymphocytes is greater than that of ACI versus Lewis, but is less than that between Lewis responder cells against ACI stimulators

  13. Prolongation of segmental and pancreaticoduodenal allografts in the primate with total-lymphoid irradiation and cyclosporine

    Energy Technology Data Exchange (ETDEWEB)

    Du Toit, D.F.; Heydenrych, J.J.; Smit, B.; Louw, G.; Zuurmond, T.; Els, D.; Du Toit, L.B.; Weideman, A.; Davids, H.; van der Merwe, E.

    1987-09-01

    The prolongation of segmental and pancreaticoduodenal allografts (PDA) by total lymphoid irradiation (TLI) and in combination with cyclosporine (CsA) was assessed in a well established total pancreatectomy, diabetic, primate transplantation model. Pancreatic transplantation was performed in 119 pancreatectomized baboons (Papio ursinus). Of a total of 109 allografts performed, 71 were segmental allografts (open duct drainage) and 38 PDA. Of 119 graft recipients, 10 received segmental pancreatic autografts. TLI and CsA administered separately to segmental allograft recipients resulted in modest allograft survival and indefinite graft survival was not observed. 8 of 17 (47%) segmental allograft recipients that received TLI and CsA had graft survival beyond 100 days, indicating highly significant pancreatic allograft survival. All long-term segmental allograft recipients were rendered normoglycemic (plasma glucose less than 8 mmol/L) by this immunosuppressive regimen. In contrast, poor results were observed in PDA recipients treated with TLI and CsA. Mean survival in 18 treated PDA recipients was 23.8 days, 8 survived longer than 20 days (44.4%), and 1 greater than 100 days (5.5%). Despite treatment, early rejection of the duodenum in PDA recipients frequently resulted in necrosis and perforation and contributed to a high morbidity and mortality. This study indicates that, in contrast to the significant prolongation of segmental allografts by TLI and CsA, poor immunosuppression was achieved by this regimen in PDA recipients and was associated with a high morbidity and mortality caused by early rejection of the duodenum.

  14. Prolongation of segmental and pancreaticoduodenal allografts in the primate with total-lymphoid irradiation and cyclosporine

    International Nuclear Information System (INIS)

    Du Toit, D.F.; Heydenrych, J.J.; Smit, B.

    1987-01-01

    The prolongation of segmental and pancreaticoduodenal allografts (PDA) by total lymphoid irradiation (TLI) and in combination with cyclosporine (CsA) was assessed in a well established total pancreatectomy, diabetic, primate transplantation model. Pancreatic transplantation was performed in 119 pancreatectomized baboons (Papio ursinus). Of a total of 109 allografts performed, 71 were segmental allografts (open duct drainage) and 38 PDA. Of 119 graft recipients, 10 received segmental pancreatic autografts. TLI and CsA administered separately to segmental allograft recipients resulted in modest allograft survival and indefinite graft survival was not observed. 8 of 17 (47%) segmental allograft recipients that received TLI and CsA had graft survival beyond 100 days, indicating highly significant pancreatic allograft survival. All long-term segmental allograft recipients were rendered normoglycemic (plasma glucose less than 8 mmol/L) by this immunosuppressive regimen. In contrast, poor results were observed in PDA recipients treated with TLI and CsA. Mean survival in 18 treated PDA recipients was 23.8 days, 8 survived longer than 20 days (44.4%), and 1 greater than 100 days (5.5%). Despite treatment, early rejection of the duodenum in PDA recipients frequently resulted in necrosis and perforation and contributed to a high morbidity and mortality. This study indicates that, in contrast to the significant prolongation of segmental allografts by TLI and CsA, poor immunosuppression was achieved by this regimen in PDA recipients and was associated with a high morbidity and mortality caused by early rejection of the duodenum

  15. Selective lymphoid irradiation: III. Prolongation of cardiac xenografts and allografts in presensitized rats

    International Nuclear Information System (INIS)

    Hardy, M.A.; Oluwole, S.; Fawwaz, R.; Satake, K.; Nowygrod, R.; Reemtsma, K.

    1982-01-01

    Selective lymphoid irradiation (SLI) with palladium-109-hematoporphyrin (Pd-H) combined with antilymphocyte globulin (ALG) induces either donor-specific permanent rat heart allograft acceptance or significant allograft prolongation depending on the degree of donor-recipient matching. The purpose of this study was to determine if SLI combined with ALG can affect ACI heart allograft survival in Lewis recipients presensitized to ACI, and of hamster heart xenografts of Lewis rats. SLI combined with ALG delays allograft and xenograft rejection in the presence of induced or preformed antidonor antibodies, and converts primarily a humoral rejection into a cellular rejection by mechanisms as yet uncertain. Such peritransplant treatment had significant effect on the levels of antidonor complement-dependent cytotoxic antibody titers but did not correlate directly with graft survival. Histological analysis of rejected hearts in all groups demonstrated primarily a humoral hyperacute rejection in control animals and in recipients treated with ALG alone, while peritransplant treatment with Pd-H and ALG resulted not only in prolonged graft survival but histologically, primarily a cellular rejection of the graft

  16. Toxoplasma gondii Cyclic AMP-Dependent Protein Kinase Subunit 3 Is Involved in the Switch from Tachyzoite to Bradyzoite Development

    Directory of Open Access Journals (Sweden)

    Tatsuki Sugi

    2016-05-01

    Full Text Available Toxoplasma gondii is an obligate intracellular apicomplexan parasite that infects warm-blooded vertebrates, including humans. Asexual reproduction in T. gondii allows it to switch between the rapidly replicating tachyzoite and quiescent bradyzoite life cycle stages. A transient cyclic AMP (cAMP pulse promotes bradyzoite differentiation, whereas a prolonged elevation of cAMP inhibits this process. We investigated the mechanism(s by which differential modulation of cAMP exerts a bidirectional effect on parasite differentiation. There are three protein kinase A (PKA catalytic subunits (TgPKAc1 to -3 expressed in T. gondii. Unlike TgPKAc1 and TgPKAc2, which are conserved in the phylum Apicomplexa, TgPKAc3 appears evolutionarily divergent and specific to coccidian parasites. TgPKAc1 and TgPKAc2 are distributed in the cytomembranes, whereas TgPKAc3 resides in the cytosol. TgPKAc3 was genetically ablated in a type II cyst-forming strain of T. gondii (PruΔku80Δhxgprt and in a type I strain (RHΔku80Δhxgprt, which typically does not form cysts. The Δpkac3 mutant exhibited slower growth than the parental and complemented strains, which correlated with a higher basal rate of tachyzoite-to-bradyzoite differentiation. 3-Isobutyl-1-methylxanthine (IBMX treatment, which elevates cAMP levels, maintained wild-type parasites as tachyzoites under bradyzoite induction culture conditions (pH 8.2/low CO2, whereas the Δpkac3 mutant failed to respond to the treatment. This suggests that TgPKAc3 is the factor responsible for the cAMP-dependent tachyzoite maintenance. In addition, the Δpkac3 mutant had a defect in the production of brain cysts in vivo, suggesting that a substrate of TgPKAc3 is probably involved in the persistence of this parasite in the intermediate host animals.

  17. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, Lotte; Martinussen, J; Møllegaard, N E

    1990-01-01

    We have investigated the regulation of the Escherichia coli deoCp2 promoter by the CytR repressor and the cyclic AMP (cAMP) receptor protein (CRP) complexed to cAMP. Promoter regions controlled by these two proteins characteristically contain tandem cAMP-CRP binding sites. Here we show that (i) Cyt......R selectively regulated cAMP-CRP-dependent initiations, although transcription started from the same site in deoCp2 in the absence or presence of cAMP-CRP; (ii) deletion of the uppermost cAMP-CRP target (CRP-2) resulted in loss of CytR regulation, but had only a minor effect on positive control by the cAMP...

  18. Graft nephrectomy: The SGPGI experience

    Directory of Open Access Journals (Sweden)

    Nand Kishore Arvind

    2002-01-01

    Full Text Available Background: Graft nephrectomy is often considered a hazardous procedure with high morbidity and occasional mortality, and this may pose a technical challenge. The aim of this study was to evaluate the indications, etiology and complications following graft nephrectomy. Materials and Methods: From 1988 to 2001, among total of 1,019 live related renal transplants carried at our center, 46 underwent graft nephrectomy. Patients were divided into 2 groups depending on timing of graft re-moval. The early group included 27 patients (within 2 months of transplantation while in late group (graft re-moval after 2 months of transplantation there were 19 patients. The 2 groups were compared in terms of indica-tion, etiology and complications. Results: In early group the indications for graft removal were acute rejection, thrombosis/infarction and hyper-acute rejection, while in late group the indications were pain, hematuria, fever, hypertension and infection along with chronic failure. Overall, the external iliac artery in-jury occurred in I and 4 patients in early and late group respectively. Major blood loss occurred in I and 6 pa-tients in early and late graft removal respectively. There were 2 deaths in early group due to ftdminant pneumoni-tis that progressed to sepsis and disseminated intravascu-lar coagulation. There were 9 major wound infections all in early group except in 2 patients of late group. Respira-tory infections occurred in 14 patients in early group and 1 in late group. In early group patients had CNS compli-cations in form of seizures, clinical depression and delusional psychosis in 12 patients. Conclusions: Our experience highlights the risk in-volved in graft nephrectomies. Severe acute rejection and thrombosis lead to early graft nephrectomies. Pain, hematuria, infection and hypertension in setting of chronic rejection are predominant causes for the delayed graft ne- phrectomies. Early graft nephrectomy, though technically easy, is

  19. Unexplained Graft Dysfunction after Heart Transplantation—Role of Novel Molecular Expression Test Score and QTc-Interval: A Case Report

    Directory of Open Access Journals (Sweden)

    Khurram Shahzad

    2010-01-01

    Full Text Available In the current era of immunosuppressive medications there is increased observed incidence of graft dysfunction in the absence of known histological criteria of rejection after heart transplantation. A noninvasive molecular expression diagnostic test was developed and validated to rule out histological acute cellular rejection. In this paper we present for the first time, longitudinal pattern of changes in this novel diagnostic test score along with QTc-interval in a patient who was admitted with unexplained graft dysfunction. Patient presented with graft failure with negative findings on all known criteria of rejection including acute cellular rejection, antibody mediated rejection and cardiac allograft vasculopathy. The molecular expression test score showed gradual increase and QTc-interval showed gradual prolongation with the gradual decline in graft function. This paper exemplifies that in patients presenting with unexplained graft dysfunction, GEP test score and QTc-interval correlate with the changes in the graft function.

  20. Graft union formation in Douglas-fir.

    Science.gov (United States)

    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  1. Grafting compatibility between selected rootstocks and Tanzanian ...

    African Journals Online (AJOL)

    The grafted seedlings with graft union tied using grafting clips were healed in a dark chamber for three days and then in a transparent chamber for three days. The average temperature and relative humidity in both chambers were maintained at 21-30°C and 85-95 %, respectively. The grafted seedlings were hardened for ...

  2. Safety information on QT-interval prolongation

    DEFF Research Database (Denmark)

    Warnier, Miriam J; Holtkamp, Frank A; Rutten, Frans H

    2014-01-01

    Prolongation of the QT interval can predispose to fatal ventricular arrhythmias. Differences in QT-labeling language can result in miscommunication and suboptimal risk mitigation. We systematically compared the phraseology used to communicate on QT-prolonging properties of 144 drugs newly approve...

  3. Saphenous vein graft vs. radial artery graft searching for the best second coronary artery bypass graft

    Science.gov (United States)

    Al-Sabti, Hilal Ali; Al Kindi, Adil; Al-Rasadi, Khalid; Banerjee, Yajnavalka; Al-Hashmi, Khamis; Al-Hinai, Ali

    2013-01-01

    Coronary artery bypass grafting (CABG) was first used in the late 1960s. This revolutionary procedure created hope among ischemic heart disease patients. Multiple conduits are used and the golden standard is the left internal mammary artery to the left anterior descending artery. Although all approaches were advocated by doctors, the use of saphenous vein grafts became the leading approach used by the majority of cardiac surgeons in the 1970s. The radial artery graft was introduced at the same time but was not as prevalent due to complications. It was reintroduced into clinical practice in 1989. The procedure was not well received initially but it has since shown superiority in patency as well as long-term survival after CABG. This review provides a summary of characteristics, technical features and patency rates of the radial artery graft in comparison with venous conduits. Current studies and research into radial artery grafts and saphenous vein grafts for CABG are explored. However, more studies are required to verify the various findings of the positive effects of coronary artery bypass grafting with the help of radial arteries on mortality and long-lasting patency. PMID:24198449

  4. [Skin defect coverage with micro skin graft].

    Science.gov (United States)

    Gümüş, Nazim; Kaya, Yalçin; Karakaya, Sadik; Camci, Cemalettin

    2002-04-01

    The aim of this study is to coverage of the large skin defect with microskin graft. The wound coverage of the large skin defect may be difficult with auto skin graft. In these patients, split thickness skin graft may be used in a bloc shape or expanded skin graft shape and a stamp skin graft shape or expanded stamp skin graft shape. On the other hand, split thickness skin graft may be used as a micrograft shape after the mincing process, which reduces of the graft size in a few millimeters. In this study, 6 patients with skin defect was admitted in our clinic, and their skin defect was treated with micro skin graft. Expansion ratio was 1:15. Epithelialization on the wound surface was completed in 4 to 6 weeks and cobblestone appearance was observed after the wound coverage. Skin defect coverage with micrograft is an effective technique like the other skin graft coverage methods.

  5. Synthesis and characterization of polypyrrole grafted chitin

    Science.gov (United States)

    Ramaprasad, A. T.; Latha, D.; Rao, Vijayalakshmi

    2017-05-01

    Synthesis and characterization of chitin grafted with polypyrrole (PPy) is reported in this paper. Chitin is soaked in pyrrole solution of various concentrations for different time intervals and polymerized using ammonium peroxy disulphate (APS) as an initiator. Grafting percentage of polypyrrole onto chitin is calculated from weight of chitin before and after grafting. Grafting of polymer is further verified by dissolution studies. The grafted polymer samples are characterized by FTIR, UV-Vis absorption spectrum, XRD, DSC, TGA, AFM, SEM and conductivity studies.

  6. Targeted endothelial delivery of nanosized catalase immunoconjugates protects lung grafts donated after cardiac death.

    Science.gov (United States)

    Preissler, Gerhard; Loehe, Florian; Huff, Ines V; Ebersberger, Ulrich; Shuvaev, Vladimir V; Bittmann, Iris; Hermanns, Iris; Kirkpatrick, James C; Fischer, Karl; Eichhorn, Martin E; Winter, Hauke; Jauch, Karl W; Albelda, Steven M; Muzykantov, Vladimir R; Wiewrodt, Rainer

    2011-08-27

    Donor organ shortage represents a major problem in lung transplantation. Donation after cardiac death could help to expand the pool of organs, but the additional period of warm ischemia after cardiac arrest aggravates primary graft dysfunction. The pulmonary endothelium of the graft constitutes an important source and target of reactive oxygen species generated during ischemia and reperfusion. Targeted protection of graft pulmonary endothelial cells by the antioxidant enzyme catalase, conjugated with a platelet/endothelial cell adhesion molecule-1 (PECAM-1) antibody to nanosized particles (anti-PECAM/catalase conjugates), might improve outcome in lung transplantation using donors after cardiac death and prolonged hypothermic preservation. Left lung transplantation was performed in 18 pigs. Before cardiac arrest, donors received anti-PECAM/catalase, unconjugated component mixture or vehicle solution. After 90-min warm and 18-hr hypothermic ischemia, lungs were transplanted, and function was assessed during 6 hr after reperfusion. Samples of bronchoalveolar lavage fluid and lung tissue were taken thereafter. Six sham-operated animals served as controls. During 6-hr reperfusion, anti-PECAM/catalase significantly ameliorated graft function, evidenced by major improvements of gas exchange and reduced intrapulmonary shunt fraction. Furthermore, lipid peroxidation, alveolar leakage, and edema formation were reduced in protected grafts. Similarly moderate lung pathology was seen after transplantation. Augmentation of the antioxidant capacity of graft pulmonary endothelial cells with anti-PECAM/catalase nanoparticles represents a straightforward approach to enable a safe transplantation of prolonged preserved donation after cardiac death lungs. Anti-PECAM/catalase protection alleviated oxidative stress and allowed immediate reconstitution of normal gas exchange and pulmonary microcirculation, a prerequisite for improved graft and patient outcome.

  7. Prolonged Survival of Subcutaneous Allogeneic Islet Graft by Donor Chimerism without Immunosuppressive Treatment

    Directory of Open Access Journals (Sweden)

    Brend Ray-Sea Hsu

    2017-01-01

    Full Text Available The aim of this study was to investigate whether tolerance-induced protection of islets in the renal subcapsular space can also prevent subcutaneous allogeneic islets from being rejected. We used bone marrow stem cells from C57BL/6 (H2b mice to construct donor chimerism in conditioned diabetic BALB/c (H2d mice and investigated the effect of donor chimerism on engraftment and survival of subcutaneously transplanted allogeneic islets in streptozotocin-induced diabetic mice. We also studied the anti-inflammatory effect of mesenchymal stem cell on islet engraftment. Full but not low-grade or no donor chimerism was associated with successful engraftment of allogeneic islets and restoration of normoglycemia in the treated diabetic mice. The temporary hyperglycemia was 11 ± 1 versus 19 ± 5 days (p<0.05 for the mice with full donor chimerism with transplanted islets in the renal subcapsular space versus the subcutaneous space, respectively. Cotransplantation of mesenchymal stem cell did not enhance alloislet engraftment. Full multilineage donor chimerism was associated with a higher transient expansion of CD11b+ and Gr-1+ myeloid progenitor cells and effector memory CD4 and CD8 T cells. In conclusion, full donor chimerism protected both renal subcapsular and subcutaneous allogeneic islets in this rodent transplantation model.

  8. Bone Grafting: Sourcing, Timing, Strategies, and Alternatives.

    Science.gov (United States)

    Egol, Kenneth A; Nauth, Aaron; Lee, Mark; Pape, Hans-Christoph; Watson, J Tracy; Borrelli, Joseph

    2015-12-01

    Acute fractures, nonunions, and nonunions with bone defects or osteomyelitis often need bone graft to facilitate union. There are several factors to consider when it is determined that a bone graft is needed. These factors include the source of the bone graft (autograft vs. allograft), proper timing for placement of the bone graft, strategies to avoid further complications (particularly in the setting of osteomyelitis), and with the development of a variety of bone graft substitutes, whether alternatives to autograft are available and appropriate for the task at hand. Autograft bone has commonly been referred to as the "gold standard" of bone grafts, against which the efficacy of other grafts has been measured. The best timing for when to place a bone graft or substitute is also somewhat controversial, particularly after an open fracture or a potentially contaminated bed. The treatment of infected nonunions, particularly those that require a graft to facilitate healing, can be quite challenging. Typically, the infection is completely eradicated before placement of a bone graft, but achieving a sterile bed and the timing of a bone graft require strategic thinking and planning. This review outlines the benefits of autografts, the most suitable sites for harvesting bone grafts, the timing of bone graft procedures, the potential risks and benefits of grafting in the face of infection, and the currently available bone graft extenders.

  9. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  10. Prognostic factors for perioperative myocardial infarction and immediate mortality in patients who underwent coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Mirtha López Ramírez

    2016-03-01

    Conclusions: Older age and higher body mass index were protective prognostic factors for perioperative acute myocardial infarction events. Prolonged surgical time and complications were independently associated with perioperative infarction and mortality after coronary artery bypass graft surgery. Low preoperative glomerular filtration rate was also associated with mortality.

  11. Costal Grafting in Mandibular Reconstruction.

    Science.gov (United States)

    Bachelet, Jean-Thomas; Bourlet, Jerôme; Château, Joseph; Jacquemart, Mathieu; Dufour, Clémence; Mojallal, Ali; Gleizal, Arnaud

    2015-11-01

    Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery, and free fibular flap is the gold standard for this indication. However, there are alternatives; nonvascular bone grafting is one of them, and we present the costal grafting for mandibular reconstruction, a classic technique that is reliable, efficient, and produced less morbidity than the technique of using composite free flaps. A 9-year retrospective review of 54 patients treated surgically for mandibular reconstruction was performed. The criterion mainly analyzed was graft survival. The surgical technique was described in detail. A total of 54 patients with mandibular bone defect were identified. Five symphysis, 46 corpus, and 20 ramus defects were considered. These patients underwent reconstruction by costal grafting, and the engrafting was successful in 92.6% of cases. Dental rehabilitation with dental implants was realized in 70% of cases. The approach described in this article allowed the authors to obtain good results with costal grafting for mandibular reconstruction and dental rehabilitation. Costal grafting is a good alternative for fibula free flap in specific indications. Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery. Since the 1980s, the gold standard for these defects is the use of free fibular flap.(1) In some cases, this technique is contradicted; the surgeon then has several possibilities for the use of free osteomyocutaneous flaps (iliac crest, scapula, and serrato-costal flaps).(2-8).

  12. Neuronal activity promotes myelination via a cAMP pathway.

    Science.gov (United States)

    Malone, Misti; Gary, Devin; Yang, In Hong; Miglioretti, Anna; Houdayer, Thierry; Thakor, Nitish; McDonald, John

    2013-06-01

    Neuronal activity promotes myelination in vivo and in vitro. However, the molecular events that mediate activity-dependent myelination are not completely understood. Seven, daily 1 h sessions of patterned electrical stimulation (ESTIM) promoted myelin segment formation in mixed cultures of dorsal root ganglion (DRG) neurons and oligodendrocytes (OLs); the increase in myelination was frequency-dependent. Myelin segment formation was also enhanced following exposure of DRGs to ESTIM prior to OL addition, suggesting that ESTIM promotes myelination in a manner involving neuron-specific signaling. Cyclic adenosine monophosphate (cAMP) levels in DRGs were increased three-fold following ESTIM, and artificially increasing cAMP mimicked the ability of ESTIM to promote myelination. Alternatively, inhibiting the cAMP pathway suppressed ESTIM-induced myelination. We used compartmentalized, microfluidic platforms to isolate DRG soma from OLs and assessed cell-type specific effects of ESTIM on myelination. A selective increase or decrease in DRG cAMP levels resulted in enhanced or suppressed myelination, respectively. This work describes a novel role for the cAMP pathway in neurons that results in enhanced myelination. Copyright © 2013 Wiley Periodicals, Inc.

  13. Primary graft dysfunction.

    Science.gov (United States)

    Suzuki, Yoshikazu; Cantu, Edward; Christie, Jason D

    2013-06-01

    Primary graft dysfunction (PGD) is a syndrome encompassing a spectrum of mild to severe lung injury that occurs within the first 72 hours after lung transplantation. PGD is characterized by pulmonary edema with diffuse alveolar damage that manifests clinically as progressive hypoxemia with radiographic pulmonary infiltrates. In recent years, new knowledge has been generated on risks and mechanisms of PGD. Following ischemia and reperfusion, inflammatory and immunological injury-repair responses appear to be key controlling mechanisms. In addition, PGD has a significant impact on short- and long-term outcomes; therefore, the choice of donor organ is impacted by this potential adverse consequence. Improved methods of reducing PGD risk and efforts to safely expand the pool are being developed. Ex vivo lung perfusion is a strategy that may improve risk assessment and become a promising platform to implement treatment interventions to prevent PGD. This review details recent updates in the epidemiology, pathophysiology, molecular and genetic biomarkers, and state-of-the-art technical developments affecting PGD. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  14. Radiation grafting on natural films

    International Nuclear Information System (INIS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37–40 N mm −1 ) and puncture deformation (PD=6.5–9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282–296 N mm −1 and PD of 5.0–5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films. - Highlights: • Irradiation of zein

  15. Grafted vegetables – the influence of rootstock and scion on postharvest quality

    Directory of Open Access Journals (Sweden)

    Fallik Elazar

    2014-12-01

    Full Text Available Grafting of vegetable seedlings is a unique horticultural technology, practised for more than 50 years, to overcome problems associated with intensive cultivation on limited arable land. Grafting vegetables can protect against soil-borne diseases and nematodes, against abiotic stresses such as high/low temperatures, salinity, drought or excessive soil-water content, and against elevated soil concentrations of heavy metals and organic pollutants. In addition, the grafted plant takes up water and nutrients from the soil more efficiently and retains its vitality for longer periods during the growing season. However, rootstock/scion combinations may affect and alter the final size, yield, and quality of fruits from grafted plants, both immediately postharvest and during prolonged storage. These alterations may be attributed in part to differing production environments and methods, the type of rootstock/scion combinations used, and harvest date. The aim of this paper is to review the most recent literature on the effects of grafting on postharvest quality of fruits/vegetables: tomato, watermelon, melon, eggplant, cucumber and pepper. The review will conclude by identifying several prospects for future research aimed at improving the quality of grafted fruit/vegetable products.

  16. Prolonged ischemic heart disease and coronary artery bypass - relation to contractile reserve

    DEFF Research Database (Denmark)

    Kofoed, Klaus F; Bangsgaard, Regitze; Carstensen, Steen

    2002-01-01

    OBJECTIVE: A major effect of coronary artery bypass grafting (CABG) in patients with ischemic heart disease and impaired left ventricular (LV) contractile function is believed to be an improvement in LV function due to recovery of dysfunctional, but viable myocardium. However, recent studies have...... indicated a time limit for such a recovery. We therefore investigated the extent of viable myocardium in patients with impaired LV function due to ischemic heart disease after a prolonged strategy of medical treatment and its relation to changes in clinical variables after CABG. METHODS: Forty......-five consecutive patients with a mean duration of ischemic heart symptoms of 9 years and LV ejection fraction (EF) stress...

  17. Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype

    DEFF Research Database (Denmark)

    Jørgensen, Rikke Lind; Nielsen, Jesper Boye; Friis-Møller, Alice

    2010-01-01

    . Hyperproduction of AmpC beta-lactamase was confirmed by isoelectric focusing (IEF). The presence of a plasmid-mediated ampC gene (pAmpC) was detected by multiplex PCR. The promoter and the entire reading frame of the chromosomal ampC gene were sequenced to identify promoter mutations associated...... by multilocus sequence typing (MLST). The remaining isolates all had mutations or insertions in the promoter region, which could explain increased expression of the chromosomal AmpC enzyme. Mutations in the ampC gene associated with extended activity were rare and did not cause resistance to cefepime...

  18. Glucose Enhances Basal or Melanocortin-Induced cAMP-Response Element Activity in Hypothalamic Cells

    Science.gov (United States)

    Wicht, Kristina; Boekhoff, Ingrid; Glas, Evi; Lauffer, Lisa; Mückter, Harald; Gudermann, Thomas

    2016-01-01

    Melanocyte-stimulating hormone (MSH)-induced activation of the cAMP-response element (CRE) via the CRE-binding protein in hypothalamic cells promotes expression of TRH and thereby restricts food intake and increases energy expenditure. Glucose also induces central anorexigenic effects by acting on hypothalamic neurons, but the underlying mechanisms are not completely understood. It has been proposed that glucose activates the CRE-binding protein-regulated transcriptional coactivator 2 (CRTC-2) in hypothalamic neurons by inhibition of AMP-activated protein kinases (AMPKs), but whether glucose directly affects hypothalamic CRE activity has not yet been shown. Hence, we dissected effects of glucose on basal and MSH-induced CRE activation in terms of kinetics, affinity, and desensitization in murine, hypothalamic mHypoA-2/10-CRE cells that stably express a CRE-dependent reporter gene construct. Physiologically relevant increases in extracellular glucose enhanced basal or MSH-induced CRE-dependent gene transcription, whereas prolonged elevated glucose concentrations reduced the sensitivity of mHypoA-2/10-CRE cells towards glucose. Glucose also induced CRCT-2 translocation into the nucleus and the AMPK activator metformin decreased basal and glucose-induced CRE activity, suggesting a role for AMPK/CRTC-2 in glucose-induced CRE activation. Accordingly, small interfering RNA-induced down-regulation of CRTC-2 expression decreased glucose-induced CRE-dependent reporter activation. Of note, glucose also induced expression of TRH, suggesting that glucose might affect the hypothalamic-pituitary-thyroid axis via the regulation of hypothalamic CRE activity. These findings significantly advance our knowledge about the impact of glucose on hypothalamic signaling and suggest that TRH release might account for the central anorexigenic effects of glucose and could represent a new molecular link between hyperglycaemia and thyroid dysfunction. PMID:27144291

  19. Sequential Vein Bypass Grafting is Not Associated with an Increase of Either In-hospital or Mid-term Adverse Events in Off-pump Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Fucheng Xiao

    2015-01-01

    Full Text Available Background: The impact of sequential vein bypass grafting on clinical outcomes is less known in off-pump coronary artery bypass grafting (CABG. We aimed to evaluate the effects of sequential vein bypass grafting on clinical outcomes in off-pump CABG. Methods: From October 2009 to September 2013 at the Fuwai Hospital, 127 patients with at least one sequential venous graft were matched with 127 patients of individual venous grafts only, using propensity score matching method to obtain risk-adjusted outcome comparison. In-hospital measurement was composite outcome of in-hospital death, myocardial infarction (MI, stroke, requirement for intra-aortic ballon pump (IABP assistance and prolonged ventilation. Major adverse cardiac events (MACEs: Death, MI or repeat revascularization and angina recurrence were considered as mid-term endpoints. Results: No significant difference was observed among the groups in baseline characteristics. Intraoperative mean blood flow per vein graft was 40.4 ml in individual venous grafts groups versus 59.5 ml in sequential venous grafts groups (P < 0.001. There were no differences between individual and sequential venous grafts groups with regard to composite outcome of in-hospital mortality, MI, stroke, IABP assistance and prolonged ventilation (11.0% vs. 14.2%, P = 0.45. Individual in-hospital measurement also did not differ significantly between the two groups. At about four years follow-up, the survival estimates free from MACEs (92.5% vs. 97.3%, P = 0.36 and survival rates free of angina recurrence (80.9% vs. 85.5%, P = 0.48 were similar among individual and sequential venous grafts groups with a mean follow-up of 22.5 months. In the Cox regression analysis, sequential vein bypass grafting was not identified as an independent predictor of both MACEs and angina recurrence. Conclusions: Compared to individual vein bypass grafting, sequential vein bypass grafting was not associated with an increase of either in

  20. [Delayed graft function: a frequent but still unsolved problem in renal transplantation].

    Science.gov (United States)

    Szwarc, Ilan; Garrigue, Valérie; Delmas, Sylvie; Deleuze, Sébastien; Chong, Guillaume; Mourad, Georges

    2005-12-01

    Delayed graft function (DGF) is a frequent and well-known complication of renal transplantation, which occurs in 30% of cadaver kidney allografts. It has an economic cost that is the result of prolonged patient hospitalization and the need for hemodialysis sessions; it also increases the risk of acute allograft rejection and may affect long-term graft survival. Lots of risk factors were identified, like donor hemodynamic compromise or prolonged cold ischemia time; however, incidence of DGF remains high due to the frequent use of marginal donors due to organ shortage. Recent advances in the pathophysiology of DGF point the importance of the ischemia-reperfusion injury mechanisms and some therapeutics that may reduce them are under investigation, like the use of new solutions to improve organ preservation and the use of some antioxidant and anti-inflammatory drugs.

  1. Gamma and neutron irradiation tests on commercial IC op amps

    International Nuclear Information System (INIS)

    Kennedy, E.J.; Morris, A.C. Jr.; Su, D.K.

    1985-01-01

    Experimental results of gamma and neutron irradiation tests on 30 types of integrated-circuit operational amplifiers from 11 manufacturers are presented. All units were low-cost, commercial-grade devices. Op amps were evaluated for changes in offset voltage, input bias current, power supply current, open-loop gain, gain-bandwidth product, slew rate, power-supply and common-mode rejection ratios. Bipolar transistor op amps with resistive collector load resistors for the input stage indicated the best radiation hardness

  2. Prolonged Pregnancy: Methods, Causal Determinants and Outcome

    DEFF Research Database (Denmark)

    Olesen, Annette Wind

    ) to study the incidence of prolonged pregnancy as a function of methods for determining gestational age; 2) to determine the risk of obstetrical and fetal complications in prolonged pregnancy; 3) to validate the self-reported gestational age in the National Birth Cohort; 4) to determine whether...... an ultrasound scan in the first or second trimester, or menstrual history was best at predicting the day of delivery; 5) to study the risk of recurrence of prolonged pregnancy as a function of change in male partner, social status and municipality; and 6) to detect prenatal risk indicators of prolonged...... pregnancy. Data from the Medical Birth Registry and the National Discharge Register from the period 1978 to 1995 were used to study the incidence of post-term delivery and determine the risk of complications associated with this condition (I). Data were furthermore linked to the Fertility Database to study...

  3. Prenatal risk indicators of a prolonged pregnancy

    DEFF Research Database (Denmark)

    Olesen, Annette Wind; Westergaard, Jes Grabow; Olsen, Jørn

    2006-01-01

    . Statistical analyses were done using logistic regression. RESULTS: Women with a pre-pregnancy body mass index of 25 kg/m2 or more had a high risk of prolonged pregnancy. If the pre-pregnancy body mass index was 35 kg/m2 or more the odds ratio was 1.52 (95% CI 1.28-1.82). Nulliparity also increased the risk......BACKGROUND: Few prenatal risk factors of prolonged pregnancy, a pregnancy of 42 weeks or more, are known. The objective was to examine whether sociodemographic, reproductive, toxicologic, or medical health conditions were associated with the risk of prolonged pregnancy. METHODS: Data from...... of prolonged pregnancy (OR (95% CI) = 1.35 (1.27-1.44)). CONCLUSIONS: The risk of post-term delivery was high in women with a pre-pregnancy body mass index of 25 kg/m2 or more, and in nulliparous women....

  4. Prolonged wakefulness induces experience-dependent synaptic plasticity in mouse hypocretin/orexin neurons.

    Science.gov (United States)

    Rao, Yan; Liu, Zhong-Wu; Borok, Erzsebet; Rabenstein, Rebecca L; Shanabrough, Marya; Lu, Min; Picciotto, Marina R; Horvath, Tamas L; Gao, Xiao-Bing

    2007-12-01

    Sleep is a natural process that preserves energy, facilitates development, and restores the nervous system in higher animals. Sleep loss resulting from physiological and pathological conditions exerts tremendous pressure on neuronal circuitry responsible for sleep-wake regulation. It is not yet clear how acute and chronic sleep loss modify neuronal activities and lead to adaptive changes in animals. Here, we show that acute and chronic prolonged wakefulness in mice induced by modafinil treatment produced long-term potentiation (LTP) of glutamatergic synapses on hypocretin/orexin neurons in the lateral hypothalamus, a well-established arousal/wake-promoting center. A similar potentiation of synaptic strength at glutamatergic synapses on hypocretin/orexin neurons was also seen when mice were sleep deprived for 4 hours by gentle handling. Blockade of dopamine D1 receptors attenuated prolonged wakefulness and synaptic plasticity in these neurons, suggesting that modafinil functions through activation of the dopamine system. Also, activation of the cAMP pathway was not able to further induce LTP at glutamatergic synapses in brain slices from mice treated with modafinil. These results indicate that synaptic plasticity due to prolonged wakefulness occurs in circuits responsible for arousal and may contribute to changes in the brain and body of animals experiencing sleep loss.

  5. "cAMP sponge": a buffer for cyclic adenosine 3', 5'-monophosphate.

    Directory of Open Access Journals (Sweden)

    Konstantinos Lefkimmiatis

    Full Text Available BACKGROUND: While intracellular buffers are widely used to study calcium signaling, no such tool exists for the other major second messenger, cyclic AMP (cAMP. METHODS/PRINCIPAL FINDINGS: Here we describe a genetically encoded buffer for cAMP based on the high-affinity cAMP-binding carboxy-terminus of the regulatory subunit RIbeta of protein kinase A (PKA. Addition of targeting sequences permitted localization of this fragment to the extra-nuclear compartment, while tagging with mCherry allowed quantification of its expression at the single cell level. This construct (named "cAMP sponge" was shown to selectively bind cAMP in vitro. Its expression significantly suppressed agonist-induced cAMP signals and the downstream activation of PKA within the cytosol as measured by FRET-based sensors in single living cells. Point mutations in the cAMP-binding domains of the construct rendered the chimera unable to bind cAMP in vitro or in situ. Cyclic AMP sponge was fruitfully applied to examine feedback regulation of gap junction-mediated transfer of cAMP in epithelial cell couplets. CONCLUSIONS: This newest member of the cAMP toolbox has the potential to reveal unique biological functions of cAMP, including insight into the functional significance of compartmentalized signaling events.

  6. Activation of protein kinase A and exchange protein directly activated by cAMP promotes adipocyte differentiation of human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Bingbing Jia

    Full Text Available Human mesenchymal stem cells are primary multipotent cells capable of differentiating into several cell types including adipocytes when cultured under defined in vitro conditions. In the present study we investigated the role of cAMP signaling and its downstream effectors, protein kinase A (PKA and exchange protein directly activated by cAMP (Epac in adipocyte conversion of human mesenchymal stem cells derived from adipose tissue (hMADS. We show that cAMP signaling involving the simultaneous activation of both PKA- and Epac-dependent signaling is critical for this process even in the presence of the strong adipogenic inducers insulin, dexamethasone, and rosiglitazone, thereby clearly distinguishing the hMADS cells from murine preadipocytes cell lines, where rosiglitazone together with dexamethasone and insulin strongly promotes adipocyte differentiation. We further show that prostaglandin I(2 (PGI(2 may fully substitute for the cAMP-elevating agent isobutylmethylxanthine (IBMX. Moreover, selective activation of Epac-dependent signaling promoted adipocyte differentiation when the Rho-associated kinase (ROCK was inhibited. Unlike the case for murine preadipocytes cell lines, long-chain fatty acids, like arachidonic acid, did not promote adipocyte differentiation of hMADS cells in the absence of a PPARγ agonist. However, prolonged treatment with the synthetic PPARδ agonist L165041 promoted adipocyte differentiation of hMADS cells in the presence of IBMX. Taken together our results emphasize the need for cAMP signaling in concert with treatment with a PPARγ or PPARδ agonist to secure efficient adipocyte differentiation of human hMADS mesenchymal stem cells.

  7. Results of Infrainguinal Bypass with a Composite Graft Combining Polytetrafluoroethylene and Vein Graft in Absence of Appropriate Saphenous Vein Graft.

    Science.gov (United States)

    Jin, Myung Jae; Park, Ui Jun; Kim, Hyoung Tae; Roh, Young-Nam

    2017-06-01

    Use of a composite graft combining a polytetrafluoroethylene graft with an autogenous vein is an option for limb salvage in the absence of an adequate single segment vein graft. We aimed to investigate the results of infrainguinal bypass with a composite graft. We retrospectively reviewed 11 infrainguinal arterial bypasses on 11 limbs which underwent surgery from March 2012 to November 2016. Critical limb ischemia was common (63.6%) indication of bypass surgery and most (90.9%) of the patients had history of failed previous treatment including endovascular treatment (36.4%) and bypass surgery (72.7%). At the 2 years after graft implantations, primary patency and amputation-free survival of below-knee bypasses using composite graft were 73% and 76%, respectively. Infrainguinal arterial bypasses with composite graft had an acceptable patency. In patients without other alternative conduits for revascularization, bypass with a composite graft can be an option.

  8. Field measurements and interpretation of TMI-2 instrumentation: YM-AMP-7023 and YM-AMP-7025

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J E; Smith, J T; Mathis, M V

    1982-01-01

    This report describes the measurement and results of the Loose Part Monitor Channels YM-AMP-7023 and YM-AMP-7025. These instruments consist of an Endevco Model 2276 accelerometer and a model 2652M4 charge amplifier connected to the Loose Parts Monitorng System terminals by approximately 400 feet (500 feet for 7025) of cable. The instruments were being incorporated into a B and W supplied system when the measurements were taken; therefore, the equipment was not expected to be fully operational.

  9. Plant grafting: new mechanisms, evolutionary implications

    Directory of Open Access Journals (Sweden)

    Eliezer E Goldschmidt

    2014-12-01

    Full Text Available Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The ‘graft hybrid’ historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species, indicating that natural grafts may play a role in plant speciation. under certain circumstances.

  10. Plant grafting: new mechanisms, evolutionary implications.

    Science.gov (United States)

    Goldschmidt, Eliezer E

    2014-01-01

    Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Incomplete and convoluted vascular connections impede the vital upward and downward whole plant transfer routes. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The 'graft hybrid' historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species, indicating

  11. The cyclic AMP (cAMP)-cAMP receptor protein signaling system mediates resistance of Vibrio cholerae O1 strains to multiple environmental bacteriophages.

    Science.gov (United States)

    Zahid, M Shamim Hasan; Waise, T M Zaved; Kamruzzaman, M; Ghosh, Amar N; Nair, G Balakrish; Mekalanos, John J; Faruque, Shah M

    2010-07-01

    Toxigenic Vibrio cholerae, the causative agent of the epidemic diarrheal disease cholera, interacts with diverse environmental bacteriophages. These interactions promote genetic diversity or cause selective enrichment of phage-resistant bacterial clones. To identify bacterial genes involved in mediating the phage-resistant phenotype, we screened a transposon insertion library of V. cholerae O1 El Tor biotype strain C6706 to identify mutants showing altered susceptibility to a panel of phages isolated from surface waters in Bangladesh. Mutants with insertion in cyaA or crp genes encoding adenylate cyclase or cyclic AMP (cAMP) receptor protein (CRP), respectively, were susceptible to a phage designated JSF9 to which the parent strain was completely resistant. Application of the cyaA mutant as an indicator strain in environmental phage monitoring enhanced phage detection, and we identified 3 additional phages to which the parent strain was resistant. Incorporation of the cyaA or crp mutations into other V. cholerae O1 strains caused similar alterations in their phage susceptibility patterns, and the susceptibility correlated with the ability of the bacteria to adsorb these phages. Our results suggest that cAMP-CRP-mediated downregulation of phage adsorption may contribute to a mechanism for the V. cholerae O1 strains to survive predation by multiple environmental phages. Furthermore, the cyaA or crp mutant strains may be used as suitable indicators in monitoring cholera phages in the water.

  12. Utility of Covered Stents for Revision of Aging Failing Synthetic Hemodialysis Grafts: A Report of Three Cases

    International Nuclear Information System (INIS)

    Silas, Anne M.; Bettmann, Michael A.

    2003-01-01

    Three aging failing hemodialysis polytetrafluoroethylene bypass shunts, average age 44 months, previously percutaneously revised with balloon angioplasty, presented with pseudoaneurysms and recurrent thrombosis. All were treated with percutaneous covered stent placement within their affected limbs. One graft was ligated 1 month after treatment for infected overlying skin ulcer, though this graft was subsequently surgically revised with interposition graft and the covered stent portion remains functional at 19 month follow-up. The 18- and 13- month follow- up of the remaining 2 patients shows that the covered stents remained patent and they are functional and being successfully and routinely punctured for dialysis. In this elderly population, the use of covered stents may prolong the functional life of failing hemodialysis bypass grafts, reducing the number of percutaneous and surgical interventions and further sparing other vascular access sites

  13. Vascularized osseous graft for scaphoid

    International Nuclear Information System (INIS)

    Mendez Daza, Carlos Hernan; Mathoulin, Cristophe

    2004-01-01

    The most commonly used technique for treatment of pseudo-arthrosis of the scaphoid is osteo-synthesis with Kirschnet wires and cortical sponge grafts. Results reported by different teams using this procedure show no more than 90% osseous consolidation, especially in cases where vascularisation of the proximal fragment of the scaphoid is compromised. Here we present a series of ten cases of pseudo-arthrosis of the scaphoid, treated using a new surgical technique involving a vascularized osseous graft of the distal radius. Using this procedure we obtained 100% consolidation, with no complications either during the procedure or immediately post-operatively. Patients returned to work in week 15 on average. In 4 cases we observed discomfort in the area of the scar, which was successfully treated using local cortisone injection. The results obtained are very similar to those seen in the literature on the different techniques for vascularized osseous grafts for pseudo-arthrosis of the scaphoid

  14. Ecto- and cytosolic 5'-nucleotidases in normal and AMP deaminase-deficient human skeletal muscle

    DEFF Research Database (Denmark)

    Hanisch, Frank; Hellsten, Ylva; Zierz, Stephan

    2006-01-01

    In skeletal muscle, adenosine monophosphate (AMP) is mainly deaminated by AMP deaminase. However, the C34T mutation in the AMPD1 gene severely reduces AMP deaminase activity. Alternatively, intracellular AMP is dephosphorylated to adenosine via cytosolic AMP 5'-nucleotidase (cN-I). In individuals...... with a homozygous C34T mutation, cN-I might be a more important pathway for AMP removal. We determined activities of AMP deaminase, cN-I, total cytosolic 5'-nucleotidase (total cN), ecto-5'-nucleotidase (ectoN) and whole homogenate 5'-nucleotidase activity in skeletal muscle biopsies from patients with different...... AMPD1 genotypes [homozygotes for C34T mutation (TT); heterozygotes for C34T mutation (CT); and homozygotes for wild type (CC): diseased controls CC; and normal controls CC]. AMP deaminase activity showed genotype-dependent differences. Total cN activity in normal controls accounted for 57...

  15. Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype

    DEFF Research Database (Denmark)

    Jørgensen, Rikke Lind; Nielsen, Jesper Boye; Friis-Møller, Alice

    2010-01-01

    OBJECTIVES: To establish the prevalence of the AmpC beta-lactamase phenotype in clinical isolates of Escherichia coli and characterize the genetic resistance mechanisms causing the observed phenotype. METHODS: Clinical E. coli (n = 74) with reduced susceptibility to third-generation cephalosporins...... with hyperproduction and gene mutations associated with extended-spectrum AmpC (ESAC) beta-lactamase activity. RESULTS: Twenty-four isolates exhibited a positive AmpC disc test. IEF confirmed AmpC expression in all isolates except one. Four isolates contained a bla(CMY-2) gene. These were not clonally related....... Sequencing of ampC showed that most isolates were not clonally related. CONCLUSIONS: E. coli expressing an AmpC phenotype occur sporadically and cause significant resistance to cephalosporins. The majority of these are hyperproducing chromosomal ampC although some isolates have acquired pAmpC....

  16. Purification, characterization, and sequencing of novel antimicrobial peptides, Tu-AMP 1 and Tu-AMP 2, from bulbs of tulip (Tulipa gesneriana L.).

    Science.gov (United States)

    Fujimura, Masatoshi; Ideguchi, Mineo; Minami, Yuji; Watanabe, Keiichi; Tadera, Kenjiro

    2004-03-01

    Novel antimicrobial peptides (AMP), designated Tu-AMP 1 and Tu-AMP 2, were purified from the bulbs of tulip (Tulipa gesneriana L.) by chitin affinity chromatography and reverse-phase high-performance liquid chromatography (HPLC). They bind to chitin in a reversible way. They were basic peptides having isoelectric points of over 12. Tu-AMP 1 and Tu-AMP 2 had molecular masses of 4,988 Da and 5,006 Da on MALDI-TOF MS analysis, and their extinction coefficients of 1% aqueous solutions at 280 nm were 3.3 and 3.4, respectively. Half of all amino acid residues of Tu-AMP 1 and Tu-AMP 2 were occupied by cysteine, arginine, lysine, and proline. The concentrations of peptides required for 50% inhibition (IC(50)) of the growth of plant pathogenic bacteria and fungi were 2 to 20 microg/ml. The structural characteristics of Tu-AMP 1 and Tu-AMP 2 indicated that they were novel thionin-like antimicrobial peptides, though Tu-AMP 2 was a heterodimer composes of two short peptides joined with disulfide bonds.

  17. 21 CFR 862.1230 - Cyclic AMP test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cyclic AMP test system. 862.1230 Section 862.1230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862...

  18. cAMP Regulation of the lactose operon.

    Science.gov (United States)

    Szeberenyi, Jozsef

    2004-05-01

    Terms to be familiar with before you start to solve the test: lactose operon, adenylate cyclase, cAMP, catabolite activator protein (CAP), expression plasmid, lac operator, lac repressor, lactose, glucose, promoter, cis- and trans-acting factors. Copyright © 2004 International Union of Biochemistry and Molecular Biology, Inc.

  19. Modeling of CO2 absorber using an AMP solution

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan

    2006-01-01

    Abstract: An explicit model for carbon dioxide (CO2) solubility in an aqueous solution of 2-amino-2-methyl-1-propanol (AMP) has been proposed and an expression for the heat of absorption of CO2 has been developed as a function of loading and temperature. A rate-based steady-state model for CO2...

  20. Detection of Amp C Beta Lactamases in Clinical Isolates of ...

    African Journals Online (AJOL)

    A total of 81 consecutive non repetitive clinical isolates of Escherichia coli (n=40) and Klebsiella spp. (n=41) were screened for AmpC production by disc diffusion method using cefoxitin (30 Zg) disc and confirmed by inhibitor based test using boronic acid as inhibitor. A total of 16 E.coli isolates (40%) and 16 Klebsiella ...

  1. CMOS technology and current-feedback op-amps

    DEFF Research Database (Denmark)

    Bruun, Erik

    1993-01-01

    Some of the problems related to the application of CMOS technology to current-feedback operational amplifiers (CFB op-amps) are identified. Problems caused by the low device transconductance and by the absence of matching between p-channel and n-channel transistors are examined, and circuit...

  2. Cyclic AMP response element binding protein and brain-derived ...

    Indian Academy of Sciences (India)

    Madhu

    the role of CREB and BDNF in depression and as targets/mediators of antidepressant action. [Nair A and Vaidya V A 2006 Cyclic AMP response element binding protein and brain-derived neurotrophic factor: Molecules that modulate our mood?; J. Biosci. 31 423–434]. Keywords. Antidepressant; depression; hippocampus ...

  3. 0011-0030.Data Representation amp Computer Arithmetic6 IEEE ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.Data Representation amp Computer Arithmetic6 IEEE Standard Double Precision FormatIn.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News.

  4. Crosslinked Radiation-Grafted Films

    Energy Technology Data Exchange (ETDEWEB)

    Slaski, M.; Brack, H.P.; Fischer, D. [Zuercher Hochschule Winterthur (Switzerland); Peter, G. [Zuercher Hochschule Winterthur (Switzerland); Wokaun, A.; Scherer, G.G.

    2004-03-01

    Radiation-grafted membranes prepared by using styrene (S) and divinyl benzene (DVB) as graft components and subsequent sulfonation can be applied as solid polymer electrolytes in fuel cells and other electrochemical devices. The use of DVB as crosslinker has an important influence on the ex-situ properties like swelling, ionic resistivity, mechanical properties, surface energy, and oxidative stability. DVB also influences gas crossover, polarization performance, and lifetime in the fuel cell application. In spite of this importance, the actual DVB content and its extent of reaction has not been well investigated. (author)

  5. Reconstruction of mandible with pedicle bone grafts.

    Science.gov (United States)

    Kowalik, S

    1980-02-01

    Three cases of pedicle bone grafts used to reconstruct the mandible are presented. The grafts were taken from the shoulder blade, rib and clavicle. In two patients partial and in one patient total mandibles were reconstructed. Good results were obtained.

  6. Surface-Enhanced Raman Scattering of the Complexes of Silver with Adenine and dAMP

    OpenAIRE

    Otto, Cornelis; Hoeben, F.P.; Hoeben, F.P.; Greve, Jan

    1991-01-01

    The behaviour of adenine and 2'-deoxyadenosine-5'-monophosphate (dAMP) at positive surface potentials of a silver working electrode was investigated using surface-enhanced Raman scattering (SERS). The use of positive potentials in the presence of adenine or dAMP leads to a rapid accumulation of an intense spectrum. It is proposed that complexes of adenine (dAMP) with silver generate the observed spectra. Adenine and dAMP can be distinguished spectroscopically due to various different complexe...

  7. Evaluation of Replacement Grafts and Punch Grafts in the Treatment of Vitiligo

    Directory of Open Access Journals (Sweden)

    Singh Ajit Kumar

    1980-01-01

    Full Text Available Thirtycasesof vitiligo eachwithminimum of two lesions undent replacement graft and multiple punch grafts in one lesion each. Complications observed at the recipient site like infection and raised nigosed surface were significantly more in replacement grafts. Hypopigmentation of the graft was significantly more when the disease was progressive.

  8. Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype

    DEFF Research Database (Denmark)

    Jørgensen, Rikke Lind; Nielsen, Jesper Boye; Friis-Møller, Alice

    2010-01-01

    with hyperproduction and gene mutations associated with extended-spectrum AmpC (ESAC) beta-lactamase activity. RESULTS: Twenty-four isolates exhibited a positive AmpC disc test. IEF confirmed AmpC expression in all isolates except one. Four isolates contained a bla(CMY-2) gene. These were not clonally related...

  9. Estimation of cyclic AMP turnover in normal and methylprednisolone-treated dogs: effect of catecholamines.

    Science.gov (United States)

    Issekutz, T B

    1975-08-01

    The turnover rate of plasma cAMP was measured in unanesthetized normal and methylprednisolone (MP)-treated dogs with [8-3H]cAMP. Determination of specific activity was based on saturation of the specific binding protein, thus bypassing the need to know the plasma level of cAMP. In normal dogs the infusion of epinephrine increased plasma glucose by 33% and both the plasma level and rate of appearance (Ra) of cAMP 2.5-fold. Treatment with MP decreased the concentration as well as the turnover rate of cAMP by about 50%. It greatly potentiated not only the hyperglycemic effect (4-fold) of epinephrine but also the rise of plasma cAMP (8.5-fold) and that of Ra (6.8-fold). Norepinephrine infusion increased cAMP only by 50%. This effect was not potentiated by MP treatment and not altered by Na nicotinate. There was a linear correlation between plasma cAMP concentration and the rate of disappearance (Rd) of cAMP. It is concluded that: a) the increase of hepatic glycogenolysis is accompanied by a rise of cAMP output, whereas that of lipolysis is not; b) glucocorticoid treatment affects cAMP turnover; and c) the plasma level of cAMP is controlled by Ra, whereas Rd is the result of the mass-action effect of the concentration.

  10. The modulation of cell surface cAMP receptors from Dictyostelium disscoideum by ammonium sulfate

    NARCIS (Netherlands)

    Haastert, Peter J.M. van

    1985-01-01

    Dictyostelium discoideum cells contain a heterogeneous population of cell surface cAMP receptors with components possessing different affinities (Kd between 15 and 450 nM) and different off-rates of the cAMP-receptor complex (t½ between 0.7 and 150 s). The association of cAMP to the receptor and the

  11. Graft infections after surgical aortic reconstructions

    NARCIS (Netherlands)

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open

  12. Pseudomonas aeruginosa isolates from patients with cystic fibrosis have different beta-lactamase expression phenotypes but are homogeneous in the ampC-ampR genetic region

    DEFF Research Database (Denmark)

    Campbell, J I; Ciofu, O; Høiby, N

    1997-01-01

    Pseudomonas aeruginosa isolates from 1 of 17 cystic fibrosis patients produced secondary beta-lactamase in addition to the ampC beta-lactamase. Isolates were grouped into three beta-lactamase expression phenotypes: (i) beta-lactam sensitive, low basal levels and inducible beta-lactamase production......; (ii) beta-lactam resistant, moderate basal levels and hyperinducible beta-lactamase production; (iii) beta-lactam resistant, high basal levels and constitutive beta-lactamase production. Apart from a base substitution in the ampR-ampC intergenic region of an isolate with moderate......-basal-level and hyperinducible beta-lactamase production, sensitive and resistant strains were identical in their ampC-ampR genetic regions. Thus, enhanced beta-lactamase expression is due to mutations in regulatory proteins other than AmpR....

  13. The caudal septum replacement graft.

    Science.gov (United States)

    Foda, Hossam M T

    2008-01-01

    To describe a technique for reconstructing the lost tip support in cases involving caudal septal and premaxillary deficiencies. The study included 120 patients with aesthetic and functional nasal problems resulting from the loss of caudal septal and premaxillary support. An external rhinoplasty approach was performed to reconstruct the lost support using a cartilaginous caudal septum replacement graft and premaxillary augmentation with Mersilene mesh. The majority of cases (75%) involved revisions in patients who had previously undergone 1 or more nasal surgical procedures. A caudal septum replacement graft was combined with premaxillary augmentation in 93 patients (77.5%). The mean follow-up period was 3 years (range, 1-12 years). The technique succeeded in correcting the external nasal deformities in all patients and resulted in a significant improvement in breathing in 74 patients (86%) with preoperative nasal obstruction. There were no cases of infection, displacement, or extrusion. The caudal septum replacement graft proved to be very effective in restoring the lost tip support in patients with caudal septal deficiency. Combining the graft with premaxillary augmentation using Mersilene mesh helped increase support and stability over long-term follow-up.

  14. Endovascular stent grafting: a review

    International Nuclear Information System (INIS)

    Kribs, S.

    2001-01-01

    Endovascular stent grafts are intravascular devices composed of surgical graft material and a metallic frame, (Fig. 1). Their main application has been to treat aneurysms, but they have been used in vascular trauma and are being investigated for use in occlusive disease. Their advantage in treating aneurysms over conventional surgical treatment is that they are loaded into relatively small delivery systems (Fig. 2) and can be introduced to the area of interest from a remote site - usually the femoral artery. This avoids the morbidity of surgical exposure in difficult sites, such as the thoracic aorta, and lessens the cardiovascular stress to patients by eliminating the need to surgically cross-clamp the vessel being treated. The first description of abdominal aortic aneurysm exclusion by an endovascular stent graft was provided by Parodi and colleagues in 1991. Much of the early clinical experience in endovascular stent grafting was obtained from centres in Australia and Europe, and they are now reporting midterm follow-up data. There are now many centres in Canada and the United States involved in endovascular research and practice. (author)

  15. SOME TECHNIQUES IN CORNEAL GRAFTING

    African Journals Online (AJOL)

    1971-04-10

    Apr 10, 1971 ... simulate as nearly as possible the intra-ocular tension of the recipient. In this manner the apposition of the graft to the host cornea is as satisfactory as .... rected to 6/9 in spite of distortion and encroachment of the fibrotic process on the pupillary area. There has been no recurrence and inspection shows.

  16. Rabbit anti-thymocyte globulin induction therapy does not prolong survival after lung transplantation.

    Science.gov (United States)

    Hartwig, Matthew G; Snyder, Laurie D; Appel, James Z; Cantu, Ed; Lin, Shu S; Palmer, Scott M; Davis, R Duane

    2008-05-01

    Lung transplant survival is limited by the development of bronchiolitis obliterans syndrome (BOS). The strongest risk factor for BOS is acute rejection (AR). We have previously shown that rabbit anti-thymocyte globulin (RATG) induction therapy is associated with a decrease in early AR. Thus, we hypothesized that RATG induction would translate to reduced BOS and improved long-term graft survival. Forty-four lung recipients were prospectively randomized to receive conventional immunosuppression with RATG induction (RATG group) or conventional immunosuppression alone (control group). End-points included graft survival, early and total acute rejection, BOS and treatment complications. There was no difference in graft survival between the groups at 8 years (RATG: 36%; control: 23%; p = 0.48). The RATG group had fewer early rejections compared with the control group (5% vs 41%; p = 0.01). However, the overall rejection incidence did not differ (RATG: 62%; control: 68%; p = 0.52). There was a trend toward a delay in BOS onset among RATG subjects compared with control subjects (2,376 days vs 1,108 days; log rank, p = 0.15). There was no difference in the incidence of infections, but the RATG group had a higher rate of malignancies. Our results suggest that alternative approaches to anti-thymocyte induction should be pursued to reduce BOS and prolong allograft survival.

  17. Prolonged pregnancy: Methods, Causal Determinants and Outcome

    DEFF Research Database (Denmark)

    Olesen, Annette Wind

    an ultrasound scan in the first or second trimester, or menstrual history was best at predicting the day of delivery; 5) to study the risk of recurrence of prolonged pregnancy as a function of change in male partner, social status and municipality; and 6) to detect prenatal risk indicators of prolonged...... from the National Hospital Discharge Register and with ultrasound-estimated gestational age in Vejle county (II). An ultrasound scan in the second trimester was the most valid method to predict the day of delivery, followed by an ultrasound scan in the first trimester, and a corrected last menstrual...

  18. Prolonged Pregnancy: Methods, Causal Determinants and Outcome

    DEFF Research Database (Denmark)

    Olesen, Annette Wind

    an ultrasound scan in the first or second trimester, or menstrual history was best at predicting the day of delivery; 5) to study the risk of recurrence of prolonged pregnancy as a function of change in male partner, social status and municipality; and 6) to detect prenatal risk indicators of prolonged...... from the National Hospital Discharge Register and with ultrasound-estimated gestational age in Vejle county (II). An ultrasound scan in the second trimester was the most valid method to predict the day of delivery, followed by an ultrasound scan in the first trimester, and a corrected last menstrual...

  19. Activation of PKA in cell requires higher concentration of cAMP than in vitro: implications for compartmentalization of cAMP signalling.

    Science.gov (United States)

    Koschinski, Andreas; Zaccolo, Manuela

    2017-10-26

    cAMP is a ubiquitous second messenger responsible for the cellular effects of multiple hormones and neurotransmitters via activation of its main effector, protein kinase A (PKA). Multiple studies have shown that the basal concentration of cAMP in several cell types is about 1 μM. This value is well above the reported concentration of cAMP required to half-maximally activate PKA, which measures in the 100-300 nM range. Several hypotheses have been suggested to explain this apparent discrepancy including inaccurate measurements of intracellular free cAMP, inaccurate measurement of the apparent activation constant of PKA or shielding of PKA from bulk cytosolic cAMP via localization of the enzyme to microdomains with lower basal cAMP concentration. However, direct experimental evidence in support of any of these models is limited and a firm conclusion is missing. In this study we use multiple FRET-based reporters for the detection of cAMP and PKA activity in intact cells and we establish that the sensitivity of PKA to cAMP is almost twenty times lower when measured in cell than when measured in vitro. Our findings have important implications for the understanding of compartmentalized cAMP signalling.

  20. Radiochemical grafting of acryonitrile on polystyrene

    International Nuclear Information System (INIS)

    Jendrychowska-Bonamour, A.M.; Michot, C.

    1977-01-01

    Polystyrene polyacrylonitrile copolymers have been prepared by the direct radio-induced grafting method. The reaction has been carried out in a gel of polystyrene swollen by the monomer. The ungrafted polystyrene has been extracted by toluene. It has been possible to separate grafted copolymers from homopolymer traces, despite the very strong dipole-dipole interactions exhibited in solution between polyacrylonitrile chains; afterwards these grafted copolymers were fractionated by composition. The limits of solubility and the glass transition temperatures of the grafted copolymers have been determined. The properties of grafted copolymers have been compared with those of block polyacrylonitrile copolymers. (authors)

  1. Homogeneous cation exchange membrane by radiation grafting

    International Nuclear Information System (INIS)

    Kolhe, Shailesh M.; G, Agathian; Ashok Kumar

    2001-01-01

    Preparation of a strong cation exchange membrane by radiation grafting of styrene on to polyethylene (LDPE) film by mutual irradiation technique in the presence of air followed by sulfonation is described. The grafting has been carried out in the presence of air and without any additive. Low dose rate has been seen to facilitate the grafting. Further higher the grafting percentage more is the exchange capacity. The addition of a swelling agent during the sulfonation helped in achieving the high exchange capacity. The TGA-MASS analysis confirmed the grafting and the sulfonation. (author)

  2. Suppression of Virulence of Toxigenic Vibrio cholerae by Anethole through the Cyclic AMP (cAMP)-cAMP Receptor Protein Signaling System.

    Science.gov (United States)

    Zahid, M Shamim Hasan; Awasthi, Sharda Prasad; Asakura, Masahiro; Chatterjee, Shruti; Hinenoya, Atsushi; Faruque, Shah M; Yamasaki, Shinji

    2015-01-01

    Use of natural compounds as antivirulence drugs could be an alternative therapeutic approach to modify the outcome of bacterial infections, particularly in view of growing resistance to available antimicrobials. Here, we show that sub-bactericidal concentration of anethole, a component of sweet fennel seed, could suppress virulence potential in O1 El Tor biotype strains of toxigenic Vibrio cholerae, the causative agent of the ongoing 7th cholera pandemic. The expression of cholera toxin (CT) and toxin coregulated pilus (TCP), the major virulence factors of V. cholerae, is controlled through a regulatory cascade involving activation of ToxT with synergistic coupling interaction of ToxR/ToxS with TcpP/TcpH. We present evidence that anethole inhibits in vitro expression of CT and TCP in a toxT-dependent but toxR/toxS-independent manner and through repression of tcpP/tcpH, by using bead-ELISA, western blotting and quantitative real-time RT-PCR assays. The cyclic AMP (cAMP)-cAMP receptor protein (CRP) is a well-studied global signaling system in bacterial pathogens, and this complex is known to suppress expression of tcpP/tcpH in V. cholerae. We find that anethole influences the virulence regulatory cascade by over-expressing cyaA and crp genes. Moreover, suppression of toxigenic V. cholerae-mediated fluid accumulation in ligated ileum of rabbit by anethole demonstrates its potentiality as an antivirulence drug candidate against the diseases caused by toxigenic V. cholerae. Taken altogether, these results revealing a mechanism of virulence inhibition in V. cholerae by the natural compound anethole, may have relevance in designing antivirulence compounds, particularly against multiple antibiotic resistant bacterial pathogens.

  3. Suppression of Virulence of Toxigenic Vibrio cholerae by Anethole through the Cyclic AMP (cAMP-cAMP Receptor Protein Signaling System.

    Directory of Open Access Journals (Sweden)

    M Shamim Hasan Zahid

    Full Text Available Use of natural compounds as antivirulence drugs could be an alternative therapeutic approach to modify the outcome of bacterial infections, particularly in view of growing resistance to available antimicrobials. Here, we show that sub-bactericidal concentration of anethole, a component of sweet fennel seed, could suppress virulence potential in O1 El Tor biotype strains of toxigenic Vibrio cholerae, the causative agent of the ongoing 7th cholera pandemic. The expression of cholera toxin (CT and toxin coregulated pilus (TCP, the major virulence factors of V. cholerae, is controlled through a regulatory cascade involving activation of ToxT with synergistic coupling interaction of ToxR/ToxS with TcpP/TcpH. We present evidence that anethole inhibits in vitro expression of CT and TCP in a toxT-dependent but toxR/toxS-independent manner and through repression of tcpP/tcpH, by using bead-ELISA, western blotting and quantitative real-time RT-PCR assays. The cyclic AMP (cAMP-cAMP receptor protein (CRP is a well-studied global signaling system in bacterial pathogens, and this complex is known to suppress expression of tcpP/tcpH in V. cholerae. We find that anethole influences the virulence regulatory cascade by over-expressing cyaA and crp genes. Moreover, suppression of toxigenic V. cholerae-mediated fluid accumulation in ligated ileum of rabbit by anethole demonstrates its potentiality as an antivirulence drug candidate against the diseases caused by toxigenic V. cholerae. Taken altogether, these results revealing a mechanism of virulence inhibition in V. cholerae by the natural compound anethole, may have relevance in designing antivirulence compounds, particularly against multiple antibiotic resistant bacterial pathogens.

  4. Short-term exercise training in humans reduces AMPK signalling during prolonged exercise independent of muscle glycogen.

    Science.gov (United States)

    McConell, Glenn K; Lee-Young, Robert S; Chen, Zhi-Ping; Stepto, Nigel K; Huynh, Ngan N; Stephens, Terry J; Canny, Benedict J; Kemp, Bruce E

    2005-10-15

    We examined the effect of short-term exercise training on skeletal muscle AMP-activated protein kinase (AMPK) signalling and muscle metabolism during prolonged exercise in humans. Eight sedentary males completed 120 min of cycling at 66 +/- 1% , then exercise trained for 10 days, before repeating the exercise bout at the same absolute workload. Participants rested for 72 h before each trial while ingesting a high carbohydrate diet (HCHO). Exercise training significantly (P free AMP: ATP ratio and glucose disposal and increased fat oxidation. Exercise training abolished the 9-fold increase in AMPK alpha2 activity observed during pretraining exercise. Since training increased muscle glycogen content by 93 +/- 12% (P glycogen content was essentially matched pre- and post-training by exercise and a low CHO diet (LCHO; post-training muscle glycogen 52 +/- 7% less than in HCHO, P glycogen levels in the two studies we obtained very similar results. In both studies the increase in ACCbeta Ser(221) phosphorylation was reduced during exercise after training. In conclusion, there is little activation of AMPK signalling during prolonged exercise following short-term exercise training suggesting that other factors are important in the regulation of glucose disposal and fat oxidation under these circumstances. It appears that muscle glycogen is not an important regulator of AMPK activation during exercise in humans when exercise is begun with normal or high muscle glycogen levels.

  5. Dynamics of bone graft healing around implants

    Directory of Open Access Journals (Sweden)

    Narayan Venkataraman

    2015-01-01

    A few questions arise pertaining to the use of bone grafts along with implants are whether these are successful in approximation with implant. Do they accelerate bone regeneration? Are all defects ultimately regenerated with new viable bone? Is the bone graft completely resorbed or integrated in new bone? Does the implant surface characteristic positively affect osseointegration when used with a bone graft? What type of graft and implant surface can be used that will have a positive effect on the healing type and time? Finally, what are the dynamics of bone graft healing around an implant? This review discusses the cellular and molecular mechanisms of bone graft healing in general and in vicinity of another foreign, avascular body, namely the implant surface, and further, the role of bone grafts in osseointegration and/or clinical success of the implants.

  6. Sequence-selective DNA binding to the regulatory subunit of cAMP-dependent protein kinase.

    Science.gov (United States)

    Wu, J C; Wang, J H

    1989-06-15

    The fluorescence of Trp-226 in the regulatory subunit of bovine type II cAMP-dependent protein kinase is unaffected by the binding of cAMP, but is quenched by the binding of 2'-dansyl-cAMP (DNS-cAMP). Up to 67% of the fluorescence of Trp-226 can be quenched by resonant energy transfer to the DNS-cAMP bound to the first site, and 96% of the fluorescence can be quenched by saturating both sites with DNS-cAMP. The observed efficiencies of energy transfer gave a distance of 16 A between Trp-226 and the DNS-cAMP bound at the first site and a distance of 12.7 A between Trp-226 and the DNS-cAMP bound at second site. The fluorescence of Trp-226 was suppressed by incubation of RII with the self-complementary octanucleotide TGACGTCA (CRE) due to binding of the oligonucleotide to RII. A detailed study of the binding equilibrium showed that each RII(cAMP)2 molecule binds 1 molecule of CRE with Kd = 80 nM. The corresponding Kd value for cAMP-depleted RII was found to be 25-fold higher. RII was also found to bind randomly selected DNA fragments with an average Kd value much higher than that of CRE. These observations show for the first time that the binding of oligonucleotide to RII is cAMP-enhanced and sequence-selective.

  7. Cyclic AMP levels in several macroalgae and their relation to light quantity and quality.

    Science.gov (United States)

    Gordillo, Francisco J L; Segovia, María; López-Figueroa, Félix

    2004-02-01

    Total cAMP levels were measured in the macroalgae Dictyota dichotoma, Gelidium sesquipedale and Ulva rigida under different light conditions in order to study its regulation either by phytochrome or photosynthesis. Incubation in red or far-red light did not promote a phytochrome-like response; instead, it showed a synergistic effect upon cAMP accumulation. cAMP levels seemed to depend on the amount of energy applied. The correlation between photosynthetic oxygen evolution and cAMP variations at sub-saturating white light irradiance pointed to photosynthetic electron transport as involved in the regulation of cAMP accumulation at least in G. sesquipedale and U. rigida. Inhibitors of thylakoidal and mitochondrial electron transport chains reduced cAMP levels in 70 to 99%. We conclude that cAMP accumulation could be regulated by photosynthetic activity rather than phytochrome in the macroalgae studied.

  8. Involvement of intracellular cAMP in epirubicin-induced vascular endothelial cell injury

    Directory of Open Access Journals (Sweden)

    Takaaki Yamada

    2016-01-01

    Full Text Available We investigated the involvement of intracellular cAMP in endothelial cell injury induced by epirubicin. Epirubicin-induced decrease in cell viability and increase in caspase-3/7 activity were reversed by a cAMP analog dibutyryl cAMP (DBcAMP or an activator of adenylate cyclase forskolin concomitant with a phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine. Moreover, epirubicin-induced elevation of lipid peroxide levels was attenuated by DBcAMP. Interestingly, the exposure of epirubicin decreased intracellular cAMP levels before the onset of epirubicin-induced production of lipid peroxidation. These results suggest that intracellular cAMP plays an important role in epirubicin-induced endothelial cell injury.

  9. Aerobic Methane Generation From Plants (AMP)? Yes, Mostly!

    Science.gov (United States)

    Whiticar, M. J.; Ednie, A. C.

    2007-12-01

    In 2006, Keppler et al. (K) published an intriguing and revolutionary idea that aerobic methane is produced in plants (AMP) and released to the atmosphere. Their initial scaling calculations estimated the amount of AMP fluxing from living plants to range from 62-236 Tg/y and 1-7 Tg/y for plant litter. Houweling et al. (2006) (H) refined this flux to ca. 85 Tg/y PIH and 125 Tg/y present day. More recently, Dueck et al. (2007) (D) challenged the claim of AMP from intact plants. Their experiments cited "...No evidence for substantial aerobic methane emission by terrestrial plants..." (max. 0.4 ng/g h-1). Due to the significance of AMP in understanding present and palaeo-atmospheric budgets (e.g., Whiticar and Schaefer, 2007), we conducted a wide range of experiments to confirm or refute the existence and magnitude of AMP. For explanation, experiments of K were time-series batch samples measured by gas chromatography on purged and ambient samples, whereas D used continuous-flow cuvettes and measured by optical PAS with time series single injections. Our longer-term experiments with corn, wheat, tomato, red cedar, chestnut, moss and lichen (3-97 h, 32 °C) used a plant chamber, flow-through system with a GYRO, an optical spectrometer that enables continuous 1 Hz CH4 measurements with a precision of ca. 1 ppbv. We conducted over 100 chamber experiments on sterilized and non-sterilized (Cs-137 radiation) samples of: 1) intact living plants (IP), 2) fresh leaves (FL) and 3) dried leaves (DL); under both 1) high and 2) low light conditions (HL, LL), and with 1) ambient CH4 (AM, ca. 1.92 ppmv) and 2) purged methane (PM, 10 and 96 ppbv) levels. Our results demonstrate that IP-AMs have CH4 flux rates of 0.74-3.48 ng/g h-1. In contrast, IP-PMs show intense CH4 uptake rates of -28.5 to -57.9 ng/g h-1 (substantially different than K's reported emissions of 12-370 ng/g h-1 values). Our FL-AM-LL have CH4 flux rates of 0.36-2.05 ng/g h-1, whereas FL-AM-HL have significant CH4

  10. Acute Right Ventricular Dysfunction Complicating Prolonged ...

    African Journals Online (AJOL)

    We report a case of transient right ventricular dysfunction associated with prolonged cardiac tamponade, an unusual complication of uncertain etiology. We believe that in this case dynamic coronary flow restriction resulted in ischemic injury and stunning of the right ventricle. Other possible causes are briefly reviewed. Right ...

  11. Hippocampal Abnormalities after Prolonged Febrile Convulsions

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2003-11-01

    Full Text Available Hippocampal volume and T2 relaxation times were determined in an MRI study of 14 children with prolonged febrile convulsions (PFC who were investigated, 1 within 5 days of a PFC, and 2 at follow-up 4-8 months after the acute study, at the Institute of Child Health, University College, and Great Ormond Street Hospital, London, UK.

  12. Prolonged displacement may compromise resilience in Eritrean ...

    African Journals Online (AJOL)

    Objective: to assess the impact of prolonged displacement on the resilience of Eritrean mothers. Methods: an adapted SOC scale (short form) was administered. Complementary qualitative data were gathered from study participants' spontaneous reactions to and commentaries on the SOC scale. Results: Displaced ...

  13. Sperm Quality and Fertility Following Prolonged Immobilization ...

    African Journals Online (AJOL)

    Sperm Quality and Fertility Following Prolonged Immobilization Stress in Wistar Rats. ... All the females that were mated with the control males became pregnant and produced litters. On the ... These results therefore, confirm and expand existing literatures reporting impaired fertility following long-term exposure to stress.

  14. Cyclic di-AMP signaling in Listeria monocytogenes

    OpenAIRE

    Whiteley, Aaron Thomas

    2016-01-01

    The Gram positive facultative intracellular pathogen Listeria monocytogenes is both ubiquitous in the environment and is a facultative intracellular pathogen. A high degree of adaptability to different growth niches is one reason for the success of this organism. In this dissertation, two facets of L. monocytogenes, growth and gene expression have been investigated. The first portion examines the function and necessity of the nucleotide second messenger c-di-AMP, and the second portion of thi...

  15. A graphical representation of equivalence classes of AMP chain graphs

    Czech Academy of Sciences Publication Activity Database

    Roverato, A.; Studený, Milan

    2006-01-01

    Roč. 7, č. 6 (2006), s. 1045-1078 ISSN 1532-4435 R&D Projects: GA ČR GA201/04/0393 Institutional research plan: CEZ:AV0Z10750506 Keywords : chain graph * AMP Markov equivalence * strong equivalence * largest deflagged graph Subject RIV: BA - General Mathematics Impact factor: 2.255, year: 2006 http://library.utia.cas.cz/separaty/historie/studeny-0040067.pdf

  16. Covalent immobilization of antimicrobial peptides (AMPs) onto biomaterial surfaces

    OpenAIRE

    Fabiola Costa; Isabel F Carvalho; Ronald C Montelaro; Gomes, P; Cristina C L Martins

    2011-01-01

    Bacterial adhesion to biomaterials remains a major problem in the medical devices field. Antimicrobial peptides (AMPS) are well-known components of the innate immune system that can be applied to over-come biofilm-associated infections. Their relevance has been increasing as a practical alternative to conventional antibiotics, which are declining in effectiveness. The recent interest focused on these peptides can be explained by a group of special features, including a wide spectrum of activi...

  17. Carotid Baroreflex Function During Prolonged Exercise

    Science.gov (United States)

    Raven, P. B.

    1999-01-01

    Astronauts are often required to work (exercise) at moderate to high intensities for extended periods while performing extra-vehicular activities (EVA). Although the physiologic responses associated with prolonged exercise have been documented, the mechanisms involved in blood pressure regulation under these conditions have not yet been fully elucidated. An understanding of this issue is pertinent to the ability of humans to perform work in microgravity and complies with the emphasis of NASA's Space Physiology and Countermeasures Program. Prolonged exercise at a constant workload is know to result in a progressive decrease in mean arterial pressure (MAP) concomitant with a decrease in stroke volume and a compensatory increase in heart rate. The continuous decrease in MAP during the exercise, which is related to the thermoregulatory redistribution of circulating blood volume to the cutaneous circulation, raises the question as to whether there is a loss of baroreflex regulation of arterial blood pressure. We propose that with prolongation of the exercise to 60 minutes, progressive increases on central command reflect a progressive upward resetting of the carotid baroreflex (CBR) such that the operating point of the CBR is shifted to a pressure below the threshold of the reflex rendering it ineffectual in correcting the downward drift in MAP. In order to test this hypothesis, experiments have been designed to uncouple the global hemodynamic response to prolonged exercise from the central command mediated response via: (1) continuous maintenance of cardiac filling volume by intravenous infusion of a dextran solution; and (2) whole body surface cooling to counteract thermoregulatory cutaneous vasodialation. As the type of work (exercise) performed by astronauts is inherently arm and upper body dependent, we will also examine the physiologic responses to prolonged leg cycling and arm ergometry exercise in the supine positions with and without level lower body negative

  18. AMP-Inspired Deep Networks for Sparse Linear Inverse Problems

    Science.gov (United States)

    Borgerding, Mark; Schniter, Philip; Rangan, Sundeep

    2017-08-01

    Deep learning has gained great popularity due to its widespread success on many inference problems. We consider the application of deep learning to the sparse linear inverse problem, where one seeks to recover a sparse signal from a few noisy linear measurements. In this paper, we propose two novel neural-network architectures that decouple prediction errors across layers in the same way that the approximate message passing (AMP) algorithms decouple them across iterations: through Onsager correction. First, we propose a "learned AMP" network that significantly improves upon Gregor and LeCun's "learned ISTA." Second, inspired by the recently proposed "vector AMP" (VAMP) algorithm, we propose a "learned VAMP" network that offers increased robustness to deviations in the measurement matrix from i.i.d. Gaussian. In both cases, we jointly learn the linear transforms and scalar nonlinearities of the network. Interestingly, with i.i.d. signals, the linear transforms and scalar nonlinearities prescribed by the VAMP algorithm coincide with the values learned through back-propagation, leading to an intuitive interpretation of learned VAMP. Finally, we apply our methods to two problems from 5G wireless communications: compressive random access and massive-MIMO channel estimation.

  19. Software Design Document for the AMP Nuclear Fuel Performance Code

    Energy Technology Data Exchange (ETDEWEB)

    Philip, Bobby [ORNL; Clarno, Kevin T [ORNL; Cochran, Bill [ORNL

    2010-03-01

    The purpose of this document is to describe the design of the AMP nuclear fuel performance code. It provides an overview of the decomposition into separable components, an overview of what those components will do, and the strategic basis for the design. The primary components of a computational physics code include a user interface, physics packages, material properties, mathematics solvers, and computational infrastructure. Some capability from established off-the-shelf (OTS) packages will be leveraged in the development of AMP, but the primary physics components will be entirely new. The material properties required by these physics operators include many highly non-linear properties, which will be replicated from FRAPCON and LIFE where applicable, as well as some computationally-intensive operations, such as gap conductance, which depends upon the plenum pressure. Because there is extensive capability in off-the-shelf leadership class computational solvers, AMP will leverage the Trilinos, PETSc, and SUNDIALS packages. The computational infrastructure includes a build system, mesh database, and other building blocks of a computational physics package. The user interface will be developed through a collaborative effort with the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Capability Transfer program element as much as possible and will be discussed in detail in a future document.

  20. Evidence of cAMP involvement in cellobiohydrolase expression and secretion by Trichoderma reesei in presence of the inducer sophorose

    OpenAIRE

    Nogueira, Karoline Maria Vieira; Costa, Mariana do Nascimento; de Paula, Renato Graciano; Mendonça-Natividade, Flávia Costa; Ricci-Azevedo, Rafael; Silva, Roberto Nascimento

    2015-01-01

    Abstract Background The signaling second messenger cyclic AMP (cAMP) regulates many aspects of cellular function in all organisms. Previous studies have suggested a role for cAMP in the regulation of gene expression of cellulolytic enzymes in Trichoderma reesei (anamorph of Hypocrea jecorina). Methods The effects of cAMP in T. reesei were analyzed through both acti...

  1. Septal graft in laryngeal reconstruction

    International Nuclear Information System (INIS)

    Bahannan, Abdulrahman; Slavicek, A.; Taudy, M.; Chovanec, M.

    2006-01-01

    A 62-year-old woman presented with symptoms of dyspnea. Ultrasonography and computed tomography examinations revealed mass extending from the cricoid cartilage to the left lobe of thyroid gland and thyroid cartilage. Cytology revealed possibility of cartilaginous origin, which was proven to be chondrosarcoma (Grade 1) from the biopsy specimen obtained during panendosopy. She underwent one stage radical resection and immediate reconstruction of laryngeal skeleton defect by mucocartilaginous graft from the nasal septum. Her postoperative course was optimal with preservation of the laryngeal functions. Twenty-eight months postoperatively, she had to undergo total laryngectomy as a salvage procedure for the advanced local recurrence. We report on the relatively easy technique for functional reconstruction of the large laryngeal defect with the employment cartilage graft from the nasal septum. (author)

  2. Graft versus host disease prophylaxis

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Graft versus host disease prophylaxis. Cyclosporine -2.5mg/KG IV over 4 hrs q12h. - 5mg/Kg BD orally for 6 months - taper- stop at one year if no GVHD. Methotrexate :INITIAL. day +1- 15mg/m2; day + 3, 6, 11- 10 mg/m2; :CURRENT; day +1-10mg/m2; day + 3,6,11 ...

  3. Opposing activity changes in AMP deaminase and AMP-activated protein kinase in the hibernating ground squirrel.

    Directory of Open Access Journals (Sweden)

    Miguel A Lanaspa

    Full Text Available Hibernating animals develop fatty liver when active in summertime and undergo a switch to a fat oxidation state in the winter. We hypothesized that this switch might be determined by AMP and the dominance of opposing effects: metabolism through AMP deaminase (AMPD2 (summer and activation of AMP-activated protein kinase (AMPK (winter. Liver samples were obtained from 13-lined ground squirrels at different times during the year, including summer and multiples stages of winter hibernation, and fat synthesis and β-fatty acid oxidation were evaluated. Changes in fat metabolism were correlated with changes in AMPD2 activity and intrahepatic uric acid (downstream product of AMPD2, as well as changes in AMPK and intrahepatic β-hydroxybutyrate (a marker of fat oxidation. Hepatic fat accumulation occurred during the summer with relatively increased enzymes associated with fat synthesis (FAS, ACL and ACC and decreased enoyl CoA hydratase (ECH1 and carnitine palmitoyltransferase 1A (CPT1A, rate limiting enzymes of fat oxidation. In summer, AMPD2 activity and intrahepatic uric acid levels were high and hepatic AMPK activity was low. In contrast, the active phosphorylated form of AMPK and β-hydroxybutyrate both increased during winter hibernation. Therefore, changes in AMPD2 and AMPK activity were paralleled with changes in fat synthesis and fat oxidation rates during the summer-winter cycle. These data illuminate the opposing forces of metabolism of AMP by AMPD2 and its availability to activate AMPK as a switch that governs fat metabolism in the liver of hibernating ground squirrel.

  4. Identification of a specific assembly of the G protein Golf as a critical and regulated module of dopamine and adenosine-activated cAMP pathways in the striatum

    Directory of Open Access Journals (Sweden)

    Denis eHervé

    2011-08-01

    Full Text Available In the principal neurons of striatum (medium spiny neurons, MSNs, cAMP pathway is primarily activated through the stimulation of dopamine D1 and adenosine A2A receptors, these receptors being mainly expressed in striatonigral and striatopallidal MSNs, respectively. Since cAMP signaling pathway could be altered in various physiological and pathological situations, including drug addiction and Parkinson’s disease, it is of crucial importance to identify the molecular components involved in the activation of this pathway. In MSNs, cAMP pathway activation is not dependent on the classical Gs GTP-binding protein but requires a specific G protein subunit heterotrimer containing Galpha-olf/beta2/gamma7 in particular association with adenylate cyclase type 5. This assembly forms an authentic functional signaling unit since loss of one of its members leads to defects of cAMP pathway activation in response to D1 or A2A receptor stimulation, inducing dramatic impairments of behavioral responses dependent on these receptors. Interestingly, D1 receptor-dependent cAMP signaling is modulated by the neuronal levels of Galpha-olf, indicating that Galpha-olf represents the rate-limiting step in this signaling cascade and could constitute a critical element for regulation of D1 receptor responses. In both Parkinsonian patients and several animal models of Parkinson’s disease, the lesion of dopamine neurons produces a prolonged elevation of Galpha-olf levels. This observation gives an explanation for the cAMP pathway hypersensitivity to D1 stimulation, occurring despite an unaltered D1 receptor density. In conclusion, alterations in the highly specialized assembly of Galpha-olf/beta2/gamma7 subunits can happen in pathological conditions, such as Parkinson’s disease, and it could have important functional consequences in relation to changes in D1 receptor signaling in the striatum.

  5. AICA-riboside induces apoptosis of pancreatic beta cells through stimulation of AMP-activated protein kinase.

    Science.gov (United States)

    Kefas, B A; Heimberg, H; Vaulont, S; Meisse, D; Hue, L; Pipeleers, D; Van de Casteele, M

    2003-02-01

    Prolonged exposure of beta cells to low glucose concentrations triggers their apoptosis and is known to activate AMP-activated protein kinase (AMPK) in beta cell lines. We examined whether prolonged activation of AMPK can trigger apoptosis in rodent beta cells. Primary beta cells were FACS-purified from rats, and from wild-type and AMPK(alpha2)-deficient mice. AMPK activation in beta cells was induced by the adenosine analog AICA-riboside and detected by immunoblotting using a phosphospecific antibody. Apoptosis of rodent beta cells was monitored by FACS analysis of beta cell DNA content, by direct counting of apoptotic cells using fluorescence microscopy, or by measurement of their caspase-3 activity. Dose-dependent and time-dependent apoptosis of the cells, concommittant with an activation of caspase-3, were suppressed by the caspase inhibitors zVAD-fmk and zDEVD-fmk. Apoptosis induction by AICA-riboside was also prevented by adding the MAPK-inhibitor SB203580 which blocked the AICA-riboside-induced phosphorylation of AMPK. Beta cells isolated from AMPK-(alpha2)-deficient mice were resistant against AICA-riboside induced apoptosis. Sustained activation of AMPK by AICA-riboside can trigger a caspase-dependent apoptosis of pancreatic beta cells.

  6. A novel cysteine-rich antifungal peptide ToAMP4 from Taraxacum officinale Wigg. flowers.

    Science.gov (United States)

    Astafieva, A A; Rogozhin, Eugene A; Andreev, Yaroslav A; Odintsova, T I; Kozlov, S A; Grishin, Eugene V; Egorov, Tsezi A

    2013-09-01

    A novel peptide named ToAMP4 was isolated from Taraxacum officinale Wigg. flowers by a combination of acetic acid extraction and different types of chromatography: affinity, size-exclusion, and RP-HPLC. The amino acid sequence of ToAMP4 was determined by automated Edman degradation. The peptide is basic, consists of 41 amino acids, and incorporates three disulphide bonds. Due to the unusual cysteine spacing pattern, ToAMP4 does not belong to any known plant AMP family, but classifies together with two other antimicrobial peptides ToAMP1 and ToAMP2 previously isolated from the dandelion flowers. To study the biological activity of ToAMP4, it was successfully produced in a prokaryotic expression system as a fusion protein with thioredoxin. The recombinant peptide was shown to be identical to the native ToAMP4 by chromatographic behavior, molecular mass, and N-terminal amino acid sequence. The peptide displays broad-spectrum antifungal activity against important phytopathogens. Two ToAMP4-mediated inhibition strategies depending on the fungus were demonstrated. The results obtained add to our knowledge on the structural and functional diversity of AMPs in plants. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  7. Mechanism of intracellular cAMP sensor Epac2 activation: cAMP-induced conformational changes identified by amide hydrogen/deuterium exchange mass spectrometry (DXMS).

    Science.gov (United States)

    Li, Sheng; Tsalkova, Tamara; White, Mark A; Mei, Fang C; Liu, Tong; Wang, Daphne; Woods, Virgil L; Cheng, Xiaodong

    2011-05-20

    Epac2, a guanine nucleotide exchange factor, regulates a wide variety of intracellular processes in response to second messenger cAMP. In this study, we have used peptide amide hydrogen/deuterium exchange mass spectrometry to probe the solution structural and conformational dynamics of full-length Epac2 in the presence and absence of cAMP. The results support a mechanism in which cAMP-induced Epac2 activation is mediated by a major hinge motion centered on the C terminus of the second cAMP binding domain. This conformational change realigns the regulatory components of Epac2 away from the catalytic core, making the later available for effector binding. Furthermore, the interface between the first and second cAMP binding domains is highly dynamic, providing an explanation of how cAMP gains access to the ligand binding sites that, in the crystal structure, are seen to be mutually occluded by the other cAMP binding domain. Moreover, cAMP also induces conformational changes at the ionic latch/hairpin structure, which is directly involved in RAP1 binding. These results suggest that in addition to relieving the steric hindrance imposed upon the catalytic lobe by the regulatory lobe, cAMP may also be an allosteric modulator directly affecting the interaction between Epac2 and RAP1. Finally, cAMP binding also induces significant conformational changes in the dishevelled/Egl/pleckstrin (DEP) domain, a conserved structural motif that, although missing from the active Epac2 crystal structure, is important for Epac subcellular targeting and in vivo functions. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Evaluation of early coronary graft patency after coronary artery bypass graft surgery using multislice computed tomography angiography

    Directory of Open Access Journals (Sweden)

    Raissi Kamal

    2009-12-01

    Full Text Available Abstract Background Coronary artery bypass graft (CABG surgery is the standard of care in the treatment of advanced coronary artery disease, and its long-term results are affected by the failure of bypass grafts. The aim of the present study was to evaluate the early patency rate in coronary bypass grafts. Methods A total of 107 consecutive patients who underwent CABG were included in this study. Early graft patency was evaluated via computed tomography (CT angiography in the first week after surgery. Results There were a total of 366 grafts, comprised of 250 venous grafts and 116 arterial grafts. Multi-slice CT detected acute graft occlusions in 32 (8.7% of all the grafts, including 26 (10% of the 250 venous grafts and 6 (5% of the 116 arterial grafts. The patency rates obtained were 97.3% for the left internal mammary (IMA grafts, 50% for the radial artery grafts, and 50% for the right IMA grafts. Additionally, 107 (96.4% grafts to the left anterior descending artery (LAD were classified as patent, whereas 1 (30% of the 3 grafts in the left circumflex (LCX region and 1 (50% of the 2 grafts in the right coronary artery (RCA territory were found to be occluded. In the venous category, 8 (13.7% of the 58 grafts to LAD were found to be occluded. In the LCX region, 9 (8.5% of the 106 grafts were classified as occluded, while the remaining 97 (91.5% grafts were patent. The venous grafts to RCA were occluded in 9 (10.4% of the 86 grafts. Amongst the multiple preoperative, intraoperative, and postoperative factors, pump time was significantly longer in the patients with occluded grafts than in those with patent grafts (P = 0.04. Conclusion The IMA grafts had the highest early patency rate amongst the coronary bypass grafts. However, the other arterial grafts were associated with a high rate of acute occlusions.

  9. [Prolonged pain in neonates: retrospective analysis].

    Science.gov (United States)

    Lilla, Michèle; Stadelman-Diaw, Corinne; Ramelet, Anne-Sylvie

    2013-12-01

    Infants hospitalised in neonatology are inevitably exposed to pain repeatedly. Premature infants are particularly vulnerable, because they are hypersensitive to pain and demonstrate diminished behavioural responses to pain. They are therefore at risk of developing short and long-term complications if pain remains untreated. Compared to acute pain, there is limited evidence in the literature on prolonged pain in infants. However, the prevalence is reported between 20 and 40 %. This single case study aimed to identify the bio-contextual characteristics of neonates who experienced prolonged pain. This study was carried out in the neonatal unit of a tertiary referral centre in Western Switzerland. A retrospective data analysis of seven infants' profile, who experienced prolonged pain ,was performed using five different data sources. The mean gestational age of the seven infants was 32weeks. The main diagnosis included prematurity and respiratory distress syndrome. The total observations (N=55) showed that the participants had in average 21.8 (SD 6.9) painful procedures that were estimated to be of moderate to severe intensity each day. Out of the 164 recorded pain scores (2.9 pain assessment/day/infant), 14.6 % confirmed acute pain. Out of those experiencing acute pain, analgesia was given in 16.6 % of them and 79.1 % received no analgesia. This study highlighted the difficulty in managing pain in neonates who are exposed to numerous painful procedures. Pain in this population remains underevaluated and as a result undertreated.Results of this study showed that nursing documentation related to pain assessment is not systematic.Regular assessment and documentation of acute and prolonged pain are recommended. This could be achieved with clear guidelines on the Assessment Intervention Reassessment (AIR) cyclewith validated measures adapted to neonates. The adequacy of pain assessment is a pre-requisite for appropriate pain relief in neonates.

  10. Prolonged Exposure: a Rapid Treatment for Phobias

    Science.gov (United States)

    Watson, J. P.; Gaind, R.; Marks, I. M.

    1971-01-01

    Ten adult patients with long-standing specific phobias were treated by prolonged continuous exposure to their phobic objects in fantasy and reality without avoidance. All patients were greatly helped by four to five hours' treatment in two or three sessions, and all improved more after practice than after imaginal sessions. The treatment method is more economical and efficient than other methods described so far. PMID:5539135

  11. Variation in Definition of Prolonged Mechanical Ventilation.

    Science.gov (United States)

    Rose, Louise; McGinlay, Michael; Amin, Reshma; Burns, Karen Ea; Connolly, Bronwen; Hart, Nicholas; Jouvet, Philippe; Katz, Sherri; Leasa, David; Mawdsley, Cathy; McAuley, Danny F; Schultz, Marcus J; Blackwood, Bronagh

    2017-10-01

    Consistency of definitional criteria for terminology applied to describe subject cohorts receiving mechanical ventilation within ICU and post-acute care settings is important for understanding prevalence, risk stratification, effectiveness of interventions, and projections for resource allocation. Our objective was to quantify the application and definition of terms for prolonged mechanical ventilation. We conducted a scoping review of studies (all designs except single-case study) reporting a study population (adult and pediatric) using the term prolonged mechanical ventilation or a synonym. We screened 5,331 references, reviewed 539 full-text references, and excluded 120. Of the 419 studies (representing 38 countries) meeting inclusion criteria, 297 (71%) reported data on a heterogeneous subject cohort, and 66 (16%) included surgical subjects only (46 of those 66, 70% cardiac surgery). Other studies described COPD (16, 4%), trauma (22, 5%), neuromuscular (17, 4%), and sepsis (1, 0.2%) cohorts. A total of 741 terms were used to refer to the 419 study cohorts. The most common terms were: prolonged mechanical ventilation (253, 60%), admission to specialized unit (107, 26%), and long-term mechanical ventilation (79, 19%). Some authors (282, 67%) defined their cohorts based on duration of mechanical ventilation, with 154 studies (55%) using this as the sole criterion. We identified 37 different durations of ventilation ranging from 5 h to 1 y, with > 21 d being the most common (28 of 282, 7%). For studies describing a surgical cohort, minimum ventilation duration required for inclusion was ≥ 24 h for 20 of 66 studies (30%). More than half of all studies (237, 57%) did not provide a reason/rationale for definitional criteria used, with only 28 studies (7%) referring to a consensus definition. We conclude that substantial variation exists in the terminology and definitional criteria for cohorts of subjects receiving prolonged mechanical ventilation. Standardization of

  12. Fixation of tibial plateau fractures with synthetic bone graft versus natural bone graft: a comparison study.

    LENUS (Irish Health Repository)

    Ong, J C Y

    2012-06-01

    The goal of this study was to determine differences in fracture stability and functional outcome between synthetic bone graft and natural bone graft with internal fixation of tibia plateau metaphyseal defects.

  13. Use of rifampin-soaked gelatin-sealed polyester grafts for in situ treatment of primary aortic and vascular prosthetic infections.

    Science.gov (United States)

    Bandyk, D F; Novotney, M L; Johnson, B L; Back, M R; Roth, S R

    2001-01-01

    In situ treatment of artery/graft infection has distinct advantages compared to vessel excision and extra-anatomic bypass procedures. Based on animal studies of a rifampin-soaked, gelatin-impregnated polyester graft that demonstrated prolonged in vivo antibacterial activity, this antibiotic-bonded graft was used selectively in patients for in situ treatment of low-grade Gram-positive prosthetic graft infections or primary aortic infections not amenable to excision and ex situ bypass. In a 5-year period (1995-1999), 27 patients with prosthetic graft infection (aortofemoral, n = 18, femorofemoral, n = 3; axillofemoral, n = 1) or primary aortic infection (mycotic aneurysm, n = 3; infected AAA, n = 2) underwent excision of the infected vessel and in situ replacement with a rifampin soaked (45-60 mg/ml for 15 min) gelatin-impregnated polyester graft. All prosthetic graft infections were low grade in nature, caused Gram-positive bacteria (Staphylococcus epidermidis, 16; Staphylococcus aureus, 5; Streptococcus, 1), and were treated electively. Patients with mycotic aortic aneurysm presented with sepsis and underwent urgent or emergent surgery. Two (8%) patients died-1 as a result of a ruptured Salmonella mycotic aortic aneurysm and the other from methicillin-resistant S. aureus infection following deep vein replacement of an in situ replaced femorofemoral graft. No amputations or late deaths as the result of vascular infection occurred in the 25 surviving patients. Two patients developed recurrent infection caused by a rifampin-resistant S. epidermidis in a replaced aortofemoral graft limb and were successfully treated with graft excision and in situ autogenous vein replacement. Eighteen patients remain alive and clinically free of infection after a mean follow-up interval of 17 months. In situ replacement treatment using a rifampin-bonded prosthetic graft for low-grade staphylococcal arterial infection was safe, durable, and associated with eradication of clinical signs

  14. Maternal-fetal outcomes in prolonged pregnancy.

    Science.gov (United States)

    Cucco, C; Osborne, M A; Cibils, L A

    1989-10-01

    The intrapartum fetal heart rate changes, type of labor, mode of delivery, and neonatal outcome were evaluated in 379 consecutive continuously monitored prolonged pregnancies (greater than 42 weeks by history and early examination). These represent only a fraction of the total prolonged gestation population. There were 56% multiparous women, 33% less than 20 years of age, and 95% with cephalic presentation. Oxytocin was given to 76% (48% induced, 28% enhanced). Delivery was by cesarean section in 13% of patients (9% of induced cases), and 15% had forceps deliveries. Fetal heart rate alterations were observed in high proportion. Cesarean section for cephalopelvic disproportion was indicated in 60% of operations, and 13% of the fetuses weighed greater than 4000 gm. Depression occurred in 15% of infants at 1 minute and in 4% at 5 minutes. Prolonged hospital stay was seen in 9%, and postmaturity syndrome in 19%. There were four perinatal deaths (two corrected). Active induction does not appear to increase the cesarean section rate. The durations of predelivery observation may be longer because the cervices are frequently unripe. There is a high incidence of fetal heart rate alterations. Induction appears justified as an active intervention to prevent some sudden unexplained deaths.

  15. Novel expansion techniques for skin grafts

    Science.gov (United States)

    Kadam, Dinesh

    2016-01-01

    The quest for skin expansion is not restricted to cover a large area alone, but to produce acceptable uniform surfaces, robust engraftment to withstand mechanical shear and infection, with a minimal donor morbidity. Ease of the technique, shorter healing period and reproducible results are essential parameters to adopt novel techniques. Significant advances seen in four fronts of autologous grafting are: (1) Dermal–epidermal graft expansion techniques, (2) epidermal graft harvests technique, (3) melanocyte-rich basal cell therapy for vitiligo and (4) robust and faster autologous cell cultures. Meek's original concept that the sum of perimeter of smaller grafts is larger than the harvested graft, and smaller the graft size, the greater is the potential for regeneration is witnessed in newer modification. Further, as graft size becomes smaller or minced, these micrografts can survive on the wound bed exudate irrespective of their dermal orientation. Expansion produced by 4 mm × 4 mm sized Meek micrografts is 10-folds, similarly 0.8 mm × 0.8 mm size micrografts produce 100-fold expansion, which becomes 700-fold with pixel grafts of 0.3 mm × 0.3 mm size. Fractional skin harvest is another new technique with 700 μ size full thickness graft. These provide instant autologous non-cultured graft to cover extensive areas with similar quality of engraftment surface as split skin grafts. Newer tools for epidermal blister graft harvest quickly, with uniform size to produce 7-fold expansions with reproducible results. In addition, donor area heals faster with minimal scar. Melanocyte-rich cell suspension is utilised in vitiligo surgery tapping the potential of hair root melanocytes. Further advances in the cell culture to reduce the cultivation time and provide stronger epidermal sheets with dermal carrier are seen in trials. PMID:27274117

  16. Graft infections after surgical aortic reconstructions

    OpenAIRE

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open surgical reconstructions as first line of treatment for aorto-iliac diseases. Nowadays, open reconstructions are primarily reserved for patients unsuitable for endovascular reconstructions or for redo ...

  17. Outcomes of AV Fistulas and AV Grafts after Interventional Stent-Graft Deployment in Haemodialysis Patients.

    Science.gov (United States)

    Schmelter, Christopher; Raab, Udo; Lazarus, Friedrich; Ruppert, Volker; Vorwerk, Dierk

    2015-08-01

    The study was designed to assess outcomes of arteriovenous (AV) accesses after interventional stent-graft deployment in haemodialysis patients. 63 haemodialysis patients with 66 AV fistulas and AV grafts were treated by interventional stent-graft deployment from 2006 to 2012 at our hospital. Data of these patients were retrospectively analysed for location of deployed stent-grafts, occurrence and location of (re-)stenosis and (re-)thrombosis. Complex stenosis was the most frequent indication for stent-graft deployment (45.5%), followed by complications of angioplasty with vessel rupture or dissection (31.8%). A high rate of procedural success was achieved (98.5%). The most frequent location of the deployed stent-graft was the draining vein (66.7%). Stent-graft deployment was more frequent in AV grafts than in AV fistulas. Primary patency was 45.5% at 6 month, 31.3% at 12 month and 19.2% at 24 month. Primary patency was significantly better for AV fistulas than for AV grafts with deployed stent-grafts. Patency of the deployed stent-graft was much better than overall AV access primary patency with deployed stent-graft. Re-stenosis with thrombosis was the most frequent indication for re-intervention. Most frequent location of re-stenosis was the draining vein (37.1%), followed by stenosis at the AV access (29.5%) and the deployed stent-graft (23.5%). Re-stenosis and re-thrombosis remain frequent in AV fistulas and AV grafts in haemodialysis patients despite stent-graft deployment. Re-stenosis of the deployed stent-graft is, only in the minority of the cases, responsible for AV access dysfunction.

  18. Outcomes of AV Fistulas and AV Grafts after Interventional Stent-Graft Deployment in Haemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Schmelter, Christopher, E-mail: christopher.schmelter@klinikum-ingolstadt.de; Raab, Udo, E-mail: udo.raab@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Diagnostic and Interventional Radiology (Germany); Lazarus, Friedrich, E-mail: friedrich.lazarus@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Nephrology (Germany); Ruppert, Volker, E-mail: volker.ruppert@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Vascular Surgery (Germany); Vorwerk, Dierk, E-mail: dierk.vorwerk@klinikum-ingolstadt.de [Klinikum Ingolstadt, Department of Diagnostic and Interventional Radiology (Germany)

    2015-08-15

    PurposeThe study was designed to assess outcomes of arteriovenous (AV) accesses after interventional stent-graft deployment in haemodialysis patients.Materials and Methods63 haemodialysis patients with 66 AV fistulas and AV grafts were treated by interventional stent-graft deployment from 2006 to 2012 at our hospital. Data of these patients were retrospectively analysed for location of deployed stent-grafts, occurrence and location of (re-)stenosis and (re-)thrombosis. Complex stenosis was the most frequent indication for stent-graft deployment (45.5 %), followed by complications of angioplasty with vessel rupture or dissection (31.8 %).ResultsA high rate of procedural success was achieved (98.5 %). The most frequent location of the deployed stent-graft was the draining vein (66.7 %). Stent-graft deployment was more frequent in AV grafts than in AV fistulas. Primary patency was 45.5 % at 6 month, 31.3 % at 12 month and 19.2 % at 24 month. Primary patency was significantly better for AV fistulas than for AV grafts with deployed stent-grafts. Patency of the deployed stent-graft was much better than overall AV access primary patency with deployed stent-graft. Re-stenosis with thrombosis was the most frequent indication for re-intervention. Most frequent location of re-stenosis was the draining vein (37.1 %), followed by stenosis at the AV access (29.5 %) and the deployed stent-graft (23.5 %).ConclusionRe-stenosis and re-thrombosis remain frequent in AV fistulas and AV grafts in haemodialysis patients despite stent-graft deployment. Re-stenosis of the deployed stent-graft is, only in the minority of the cases, responsible for AV access dysfunction.

  19. The autologus graft of epithelial tissue culture

    Directory of Open Access Journals (Sweden)

    Minaee B

    1999-08-01

    Full Text Available With the intention of research about culture and autologus graft of epithelial tissue we used 4 french Albino Rabbits with an average age of 2 months. After reproduction on the support in EMEM (Eagle's Minimum Essential Medium we used this for graft after 4 weeks. This region which grafted total replaced. After fixation of this sample and passing them through various process, histological sections were prepared. These sections were stained with H & E and masson's trichrome and studied by light microscope. We succeeded in graft. We hope in the near future by using the method of epithelium tissue culture improving to treat burned patients.

  20. Nanomolar Inhibitors of AmpC [beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Morandi, Federica; Caselli, Emilia; Morandi, Stefania; Focia, Pamela J.; Blazquez, Jesus; Shoichet, Brian K.; Prati, Fabio (Degali); (NIH); (NWU); (UCSF)

    2010-03-08

    {beta}-lactamases are the most widespread resistance mechanism to {beta}-lactam antibiotics, such as the penicillins and the cephalosporins. In an effort to combat these enzymes, a combination of stereoselective organic synthesis, enzymology, microbiology, and X-ray crystallography was used to design and evaluate new carboxyphenyl-glycylboronic acid transition-state analogue inhibitors of the class C {beta}-lactamase AmpC. The new compounds improve inhibition by over 2 orders of magnitude compared to analogous glycylboronic acids, with K{sub i} values as low as 1 nM. On the basis of the differential binding of different analogues, the introduced carboxylate alone contributes about 2.1 kcal/mol in affinity. This carboxylate corresponds to the ubiquitous C3(4)' carboxylate of {beta}-lactams, and this energy represents the first thermodynamic measurement of the importance of this group in molecular recognition by class C {beta}-lactamases. The structures of AmpC in complex with two of these inhibitors were determined by X-ray crystallography at 1.72 and 1.83 {angstrom} resolution. These structures suggest a structural basis for the high affinity of the new compounds and provide templates for further design. The highest affinity inhibitor was 5 orders of magnitude more selective for AmpC than for characteristic serine proteases, such as chymotrypsin. This inhibitor reversed the resistance of clinical pathogens to the third generation cephalosporin ceftazidime; it may serve as a lead compound for drug discovery to combat bacterial resistance to {beta}-lactam antibiotics.

  1. Enhancing disease resistance against microbial pathogens by expression of Et-AMPs in Arabidopsis plants

    OpenAIRE

    Amran, Ammar Youssef

    2010-01-01

    The aim of the study was to detect the potency of the novel insect antimicrobial peptides Et-AMP1 and Et-AMP2 derived from drone fly Eristalis tenax to engineer disease resistance in the model plant Arabidopsis thaliana against the fungal pathogen grey mold Botrytis cinerea and the bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000. For the first antimicrobial peptide (Et-AMP1), a protocol for the production of recombinant protein in E. coli expression system was ...

  2. Absorption performance for CO2 capture process using MDEA-AMP aqueous solution

    Science.gov (United States)

    Liu, Gang; Kou, Liqing; Li, Chao

    2017-03-01

    The absorption capacity and the absorption rate of CO2 in 2-amino-2-methyl-1-propanol (AMP)-N-methyldiethanolamine (MDEA) aqueous solution were measured. The temperatures ranged from 303.2K to 323.2K. The mass fractions of AMP and MDEA respectively ranged from 0 to 0.03 and 0.2 to 0.3. The influence of temperature and w AMP on the absorption capacity and absorption rate of CO2 was illustrated.

  3. Establishment of donor Chimerism Using Allogeneic Bone Marrow with AMP Cell Co-infusion

    Science.gov (United States)

    2017-09-01

    AWARD NUMBER: W81XWH-15-1-0234 TITLE: Establishment of donor Chimerism Using Allogeneic Bone Marrow with AMP Cell Co-infusion PRINCIPAL...14/2017 4. TITLE AND SUBTITLE Establishment of donor Chimerism Using Allogeneic Bone Marrow with AMP Cell Co-infusion 5a. CONTRACT NUMBER 5b. GRANT...tolerance induction of all types of allografts. In this study, we investigate whether co-infusion of amnion- derived multipotent progenitor ( AMP ) cells

  4. Bicarbonate-responsive “soluble” adenylyl cyclase defines a nuclear cAMP microdomain

    Science.gov (United States)

    Zippin, Jonathan H.; Farrell, Jeanne; Huron, David; Kamenetsky, Margarita; Hess, Kenneth C.; Fischman, Donald A.; Levin, Lonny R.; Buck, Jochen

    2004-01-01

    Bicarbonate-responsive “soluble” adenylyl cyclase resides, in part, inside the mammalian cell nucleus where it stimulates the activity of nuclear protein kinase A to phosphorylate the cAMP response element binding protein (CREB). The existence of this complete and functional, nuclear-localized cAMP pathway establishes that cAMP signals in intracellular microdomains and identifies an alternate pathway leading to CREB activation. PMID:14769862

  5. Impact of AmpC Derepression on Fitness and Virulence: the Mechanism or the Pathway?

    Directory of Open Access Journals (Sweden)

    Marcelo Pérez-Gallego

    2016-10-01

    Full Text Available Understanding the interplay between antibiotic resistance and bacterial fitness and virulence is essential to guide individual treatments and improve global antibiotic policies. A paradigmatic example of a resistance mechanism is the intrinsic inducible chromosomal β-lactamase AmpC from multiple Gram-negative bacteria, including Pseudomonas aeruginosa, a major nosocomial pathogen. The regulation of ampC expression is intimately linked to peptidoglycan recycling, and AmpC-mediated β-lactam resistance is frequently mediated by inactivating mutations in ampD, encoding an N-acetyl-anhydromuramyl-l-alanine amidase, affecting the levels of ampC-activating muropeptides. Here we dissect the impact of the multiple pathways causing AmpC hyperproduction on P. aeruginosa fitness and virulence. Through a detailed analysis, we demonstrate that the lack of all three P. aeruginosa AmpD amidases causes a dramatic effect in fitness and pathogenicity, severely compromising growth rates, motility, and cytotoxicity; the latter effect is likely achieved by repressing key virulence factors, such as protease LasA, phospholipase C, or type III secretion system components. We also show that ampC overexpression is required but not sufficient to confer the growth-motility-cytotoxicity impaired phenotype and that alternative pathways leading to similar levels of ampC hyperexpression and resistance, such as those involving PBP4, had no fitness-virulence cost. Further analysis indicated that fitness-virulence impairment is caused by overexpressing ampC in the absence of cell wall recycling, as reproduced by expressing ampC from a plasmid in an AmpG (muropeptide permease-deficient background. Thus, our findings represent a major step in the understanding of β-lactam resistance biology and its interplay with fitness and pathogenesis.

  6. Effect of 34 kinds of traditional Japanese herbal medicines on prolongation of cardiac allograft survival.

    Science.gov (United States)

    Jin, X; Uchiyama, M; Zhang, Q; Harada, T; Otsuka, K; Shimokawa, T; Niimi, M

    2014-05-01

    Herbal medicines have been used for over 3,000 years in Asian as alternative therapy for their variety effects and have recently become popular in Europe and the United States. In the last 30 years, Japanese herbal medicines were widely used for treatment of diseases after been recognized officially by Japanese government. In this study, we investigated the effect of 34 kinds of traditional Japanese herbal medicines on alloimmune responses in a murine model of cardiac allograft transplantation. CBA mice (H2(k)) underwent transplantation of a C57BL/6 (H2(b)) heart and received oral administration of 2 g/kg/d of the 34 kinds of herbal medicines from the day of transplantation until 7 days afterward. Naïve CBA mice rejected B6 cardiac grafts acutely (median survival time [MST], 7 days). CBA transplant recipients given 2 g/kg/d of Sairei-to (TJ-114) and Tokishakuyaku-san (TJ-23) had prolonged C57BL/6 allograft survival indefinitely (both MSTs > 100 days). Moreover, CBA transplant recipients given Seisinrensiin (TJ-111), Tokishigyakukagoshuyushokyoto (TJ-38), Rikkunshito (TJ-43), Maobushisaishinto (TJ-127), Ninjin-yoei-to (TJ-108), Ryokan-kyomi-shinge-nin-to (TJ-119), Inchingorei-san (TJ-117), Hochuekkito (TJ-41), Kihi-to (TJ-65), and Sinbu-to (TJ-30) had also prolonged C57BL/6 allograft survival significantly (MSTs of 28, 22, 16, 14, 14, 13, 12, 9.5, 9 and 9 days, respectively). However, none of other 22 kinds of herbal medicines could prolong the allograft survival. Furthermore, oral administration of 2 g/kg/d of Daikenchuto (TJ-100) induced sudden death (within 1 minute) in CBA mice. In conclusion, 12 kinds of Japanese herbal medicines prolonged allograft survival and one showed toxic effect in mice. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Primary adenosine monophosphate (AMP) deaminase deficiency in a hypotonic infant.

    Science.gov (United States)

    Castro-Gago, Manuel; Gómez-Lado, Carmen; Pérez-Gay, Laura; Eirís-Puñal, Jesús; Martínez, Elena Pintos; García-Consuegra, Inés; Martín, Miguel Angel

    2011-06-01

    The spectrum of the adenosine monophosphate (AMP) deaminase deficiency ranges from asymptomatic carriers to patients who manifest exercise-induced muscle pain, occasionally rhabdomyolysis, and idiopathic hyperCKemia. However, previous to the introduction of molecular techniques, rare cases with congenital weakness and hypotonia have also been reported. We report a 6-month-old girl with the association of congenital muscle weakness and hypotonia, muscle deficiency of adenosine monophosphate deaminase, and the homozygous C to T mutation at nucleotide 34 of the adenosine monophosphate deaminase-1 gene. This observation indicates the possible existence of a primary adenosine monophosphate deaminase deficiency manifested by congenital muscle weakness and hypotonia.

  8. ChAMP: 450k Chip Analysis Methylation Pipeline.

    Science.gov (United States)

    Morris, Tiffany J; Butcher, Lee M; Feber, Andrew; Teschendorff, Andrew E; Chakravarthy, Ankur R; Wojdacz, Tomasz K; Beck, Stephan

    2014-02-01

    The Illumina Infinium HumanMethylation450 BeadChip is a new platform for high-throughput DNA methylation analysis. Several methods for normalization and processing of these data have been published recently. Here we present an integrated analysis pipeline offering a choice of the most popular normalization methods while also introducing new methods for calling differentially methylated regions and detecting copy number aberrations. ChAMP is implemented as a Bioconductor package in R. The package and the vignette can be downloaded at bioconductor.org

  9. Buddhism in Čampā Le Bouddhisme au Champa

    Directory of Open Access Journals (Sweden)

    Anne-Valérie Schweyer

    2009-10-01

    Full Text Available Čampā is a Far East country, whose Māhāyana Buddhism is known from 7th to 14th century. In fact, Sanskrit and Cam Inscriptions mostly attested Tantric practices, belonging to the Vajrāyana Buddhism, mixing Śaiva and Buddhist believes. More precisely, side by side Śiva and the three Buddha’ emanations, Śākyamuni, Amitābha and Vairocana, are honoured in Čampā, alone with the Goddess Prajñāpāramitā, the true substance of the Doctrine, and, secondary, with Vajrapāni, Lokeśvara and Vajrasattva. The confrontation of the epigraphic testimonies with the archaeological remains is very useful to understand the Buddhism of Čampā, crossroads of trade roads between India and China. Therefore, epigraphic and artistic evidences are used to propose a chronological presentation, with a special development on the revival of the 10th century, and especially, the esoteric way.Le Čampā, pays du centre Vietnam, connut un bouddhisme Māhāyana du xe au xive siècle. Les inscriptions en sanskrit et en cam montrent que ce bouddhisme était essentiellement tantrique, relevant du bouddhisme Vajrāyana, mêlant pratiques Śivaïtes et bouddhiques. Plus précisément, le bouddhisme cam montre qu’aux côtés de Śiva sont honorées les trois émanations du Bouddha, Śākyamuni, Amitābha et Vairocana, avec la déesse Prajñāpāramitā, la Vraie Substance de la Connaissance ; on trouve également Vajrapāni, Lokeśvara et Vajrasattva. La confrontation des témoignages épigraphiques et archéologiques permet de mieux appréhender le bouddhisme cam, à la croisée des routes commerciales entre l’Inde et la Chine. Cet article exploite ces témoignages dans une perspective chronologique, avec un développement particulier pour le Bouddhisme ésotérique au xe siècle.

  10. Autogenous femoral head as grafting material for mandibular augmentation

    NARCIS (Netherlands)

    Vos, M. D.; Raghoebar, G. M.; van der Wal, J. E.; Kalk, W. W. I.; Vissink, A.

    2009-01-01

    Bone grafting is commonly used for augmentation of the atrophic edentulous maxilla and mandible. Although bone substitutes and allogeneic frozen bone grafts have been applied successfully, fresh autogenous bone grafts remain the 'gold standard' in maxillofacial reconstructive surgery. A disadvantage

  11. Industrial application of electron beams for grafting and vulcanization

    International Nuclear Information System (INIS)

    Keizo Makuuchi

    1994-01-01

    The topics discussed are radiation graft polymerization; industrial application of radiation grafting - ion exchange membrane for a battery separator, ammonia adsorbent, non-flammable PE (polyethylene) foam; R and D on radiation grafting, radiation vulcanization of natural rubber

  12. Coronary vasodilatory, spasmolytic and cAMP-phosphodiesterase inhibitory properties of dihydropyranocoumarins and dihydrofuranocoumarins

    DEFF Research Database (Denmark)

    Thastrup, Ole; Fjalland, B; Lemmich, J

    1983-01-01

    Twenty-three dihydropyrano- and dihydrofuranocoumarins, most of plant origin, were examined for their effects on the coronary flow of isolated perfused guinea-pig heart, on the Ba2+-induced spasms in isolated guinea-pig ileum, on the cAMP level in guinea-pig heart homogenate and on the cAMP metab...... between the coronary vasodilatory and the cAMP-phosphodiesterase inhibitory activity. The results indicate involvement of cAMP-phosphodiesterase inhibition in coronary vasodilatory effects of acyloxydihydropyrano- and acyloxydihydrofurano-coumarins....

  13. Histamine-induced increases in cyclic AMP levels in bovine adrenal medullary cells.

    OpenAIRE

    Marley, P. D.; Thomson, K. A.; Jachno, K.; Johnston, M. J.

    1991-01-01

    1. The effect of histamine on cellular cyclic AMP levels in cultured bovine adrenal medullary cells has been studied. 2. Histamine (0.3-30 microM) increased cyclic AMP levels transiently, with a maximal response after 5 min, a smaller response after 20 min, and no increase seen after 80 or 180 min. The EC50 at 5 min was approximately 2 microM. Histamine had no effect on cyclic AMP release from the cells over 5 min, but increased it after 90 min. 3. The cyclic AMP response to 5 microM histamin...

  14. AMP-guided tumour-specific nanoparticle delivery via adenosine A1 receptor.

    Science.gov (United States)

    Dai, Tongcheng; Li, Na; Han, Fajun; Zhang, Hua; Zhang, Yuanxing; Liu, Qin

    2016-03-01

    Active targeting-ligands have been increasingly used to functionalize nanoparticles for tumour-specific clinical applications. Here we utilize nucleotide adenosine 5'-monophosphate (AMP) as a novel ligand to functionalize polymer-based fluorescent nanoparticles (NPs) for tumour-targeted imaging. We demonstrate that AMP-conjugated NPs (NPs-AMP) efficiently bind to and are following internalized into colon cancer cell CW-2 and breast cancer cell MDA-MB-468 in vitro. RNA interference and inhibitor assays reveal that the targeting effects mainly rely on the specific binding of AMP to adenosine A1 receptor (A1R), which is greatly up-regulated in cancer cells than in matched normal cells. More importantly, NPs-AMP specifically accumulate in the tumour site of colon and breast tumour xenografts and are further internalized into the tumour cells in vivo via tail vein injection, confirming that the high in vitro specificity of AMP can be successfully translated into the in vivo efficacy. Furthermore, NPs-AMP exhibit an active tumour-targeting behaviour in various colon and breast cancer cells, which is positively related to the up-regulation level of A1R in cancer cells, suggesting that AMP potentially suits for more extensive A1R-overexpressing cancer models. This work establishes AMP to be a novel tumour-targeting ligand and provides a promising strategy for future diagnostic or therapeutic applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Phosphodiesterase 3 inhibitor cilostazol induces migraine-like attacks via cyclic AMP increase

    DEFF Research Database (Denmark)

    Guo, Song; Olesen, Jes; Ashina, Messoud

    2014-01-01

    The initiating mechanisms of migraine attacks are very complex but may involve the cyclic AMP signalling pathway. It is unknown whether intracellular cyclic AMP accumulation induces migraine attacks. We investigated whether administration of cilostazol, which causes cyclic AMP accumulation, may...... and that cilostazol-induced attacks responded to their usual migraine treatment. Median time of medication intake was 6 h (range 4-11 h). The present study suggests that intracellular cyclic AMP accumulation plays a crucial role in migraine induction. This knowledge is a further step in our understanding...

  16. TSH-induced cyclic AMP production in an ovine thyroid cell line: OVNIS 5H.

    Science.gov (United States)

    Fayet, G; Aouani, A; Hovsépian, S

    1986-01-06

    The TSH-induced cyclic AMP response was studied using a 3-year-old ovine thyroid cell line TSH-independent for growth: OVNIS 5H. The kinetics of cyclic AMP production was followed both in cell layers and in cell culture media, with or without phosphodiesterase inhibitor. It is noteworthy that following the first wave in cyclic AMP obtained within minutes, we observed later a sustained exponential increase in cyclic AMP during the 5 days following TSH stimulation. A bioassay of TSH was derived allowing measurement of 1 microU/ml TSH from a crude bTSH preparation.

  17. A Universal Stress Protein (USP) in Mycobacteria Binds cAMP

    Science.gov (United States)

    Banerjee, Arka; Adolph, Ramona S.; Gopalakrishnapai, Jayashree; Kleinboelting, Silke; Emmerich, Christiane; Steegborn, Clemens; Visweswariah, Sandhya S.

    2015-01-01

    Mycobacteria are endowed with rich and diverse machinery for the synthesis, utilization, and degradation of cAMP. The actions of cyclic nucleotides are generally mediated by binding of cAMP to conserved and well characterized cyclic nucleotide binding domains or structurally distinct cGMP-specific and -regulated cyclic nucleotide phosphodiesterase, adenylyl cyclase, and E. coli transcription factor FhlA (GAF) domain-containing proteins. Proteins with cyclic nucleotide binding and GAF domains can be identified in the genome of mycobacterial species, and some of them have been characterized. Here, we show that a significant fraction of intracellular cAMP is bound to protein in mycobacterial species, and by using affinity chromatography techniques, we identify specific universal stress proteins (USP) as abundantly expressed cAMP-binding proteins in slow growing as well as fast growing mycobacteria. We have characterized the biochemical and thermodynamic parameters for binding of cAMP, and we show that these USPs bind cAMP with a higher affinity than ATP, an established ligand for other USPs. We determined the structure of the USP MSMEG_3811 bound to cAMP, and we confirmed through structure-guided mutagenesis, the residues important for cAMP binding. This family of USPs is conserved in all mycobacteria, and we suggest that they serve as “sinks” for cAMP, making this second messenger available for downstream effectors as and when ATP levels are altered in the cell. PMID:25802331

  18. Prolonged labour as indication for emergency caesarean section

    DEFF Research Database (Denmark)

    Maaløe, Nanna; Sorensen, B L; Onesmo, R

    2012-01-01

    To audit the quality of obstetric management preceding emergency caesarean sections for prolonged labour.......To audit the quality of obstetric management preceding emergency caesarean sections for prolonged labour....

  19. Positive Effect of Carbon Sources on Natural Transformation in Escherichia coli: Role of Low-Level Cyclic AMP (cAMP)-cAMP Receptor Protein in the Derepression of rpoS

    OpenAIRE

    Guo, Mengyue; Wang, Huanyu; Xie, Nengbin; Xie, Zhixiong

    2015-01-01

    Natural plasmid transformation of Escherichia coli is a complex process that occurs strictly on agar plates and requires the global stress response factor σS. Here, we showed that additional carbon sources could significantly enhance the transformability of E. coli. Inactivation of phosphotransferase system genes (ptsH, ptsG, and crr) caused an increase in the transformation frequency, and the addition of cyclic AMP (cAMP) neutralized the promotional effect of carbon sources. This implies a n...

  20. Influence of ischemia before vein grafting on early hyperplasia of the graft and the dynamic changes of the intima after grafting

    Directory of Open Access Journals (Sweden)

    Zou RongJiang

    2012-09-01

    Full Text Available Abstract Background To investigate both the influence of ischemia before grafting on early hyperplasia of the vein grafts, and the dynamic changes of the intima after grafting in a rabbit model of vein graft disease. Methods We performed paired vein graft experiments under different ischemic conditions (15 vs. 60 min; 15 vs. 90 min in the neck of the rabbits and compared the differences between the grafts. Clopidogrel, an anti-platelet agent, was administered before and after surgery. Twenty-eight days after the grafting procedure, the veins were evaluated microscopically. The dynamic changes of the intima after grafting were evaluated by scanning electron microscopy over time. Results The vein grafts subjected to 60- or 90-min ischemia exhibited no differences compared to those subjected to 15-min ischemia in terms of the mean thickness of the intimal, medial, and adventitial layers of the graft. Similarly, there was no difference in the Ki-67 labeling index (proliferation marker between the vein grafts. Vein grafts with 15-min ischemia lost endothelial cells (ECs but healed by 3 days post graft, whereas vein grafts with 90-min ischemia suffered serious EC loss, which was restored with new ECs during days 2 to 14 post graft. Conclusions Ninety-minute ischemia before vein grafting can cause serious EC loss, but does not increase early intimal hyperplasia when clopidogrel is administered. Protecting the vein from ischemia and reperfusion injury preserves ECs.

  1. Laryngotracheal Injury following Prolonged Endotracheal Intubation

    Directory of Open Access Journals (Sweden)

    J. Mehdizadeh

    2006-07-01

    Full Text Available Background: Prolonged endotracheal intubation is a growing method for supporting ventilation in patients who require intensive care. Despite considerable advancement in endotracheal intubation, this method still has some complications; the most important is laryngo-tracheal injuries. Methods: Over a 2-year period, this retrospective study was conducted on 57 patients with history of prolonged intubation who were referred to the ENT Department of Amir Alam Hospital. For each patient, a complete evaluation including history, physical examination, and direct laryngoscopy and bronchoscopy was done under general anesthesia. Results: Fifty-seven patients (44 male; mean age, 23.014.7 years were studied. Mean intubation period was 15.88 days. The most common presenting symptom was dyspnea (62%. Head trauma was responsible for most cases of intubation (72.4%. The most common types of tracheal and laryngeal lesions were tracheal (56.9% and subglottic (55.2% stenosis, respectively. Mean length of tracheal stenosis was 0.810.83 cm. There was a statistically significant relationship between length of tracheal stenosis and intubation period (P=0.0001 but no relation was observed between tracheal stenosis and age, sex, and etiology of intubation (All P=NS. Among the glottic lesions, inter- arytenoids adhesion was the most common lesion (25.9%. No statistically significant relation was found between glottic and subglottic lesions and age, sex and intubation period (all P=NS. Length of stenosis and intubation period was significantly greater in tracheal/ subglottic lesions than those in glottic/ supraglottic lesions (all P=NS. Conclusion: After prolonged endotracheal intubation, laryngo-tracheal lesions had no relation with patient’s age, sex, and cause of intubation.There was direct relation between length of tracheal stenosis and intubation period. Glottic lesions were more commonly observed in head trauma patients. Lesion length and intubation

  2. Prolonged ischemic heart disease and coronary artery bypass - relation to contractile reserve

    DEFF Research Database (Denmark)

    Kofoed, Klaus F; Bangsgaard, Regitze; Carstensen, Steen

    2002-01-01

    OBJECTIVE: A major effect of coronary artery bypass grafting (CABG) in patients with ischemic heart disease and impaired left ventricular (LV) contractile function is believed to be an improvement in LV function due to recovery of dysfunctional, but viable myocardium. However, recent studies have...... was correlated to the LV extent of myocardial metabolism--blood flow reverse mismatch. Most of the patients experienced an improvement in their angina pectoris, heart failure symptoms and exercise capacity after CABG; the overall 3-year survival was 77%. CONCLUSIONS: Patients with chronic ischemic heart disease...... indicated a time limit for such a recovery. We therefore investigated the extent of viable myocardium in patients with impaired LV function due to ischemic heart disease after a prolonged strategy of medical treatment and its relation to changes in clinical variables after CABG. METHODS: Forty...

  3. Spreader Grafts in Functional Rhinoplasty.

    Science.gov (United States)

    Kim, Leslie; Papel, Ira D

    2016-02-01

    Management of the middle vault is paramount to achieving optimal aesthetic and functional outcomes in rhinoplasty. The ideal treatment for middle vault complications, such as internal nasal valve collapse, inverted-V deformity, and middle vault dorsal asymmetry, is prevention. Risk factors for middle vault problems in rhinoplasty that may be identified in preoperative consultation include short nasal bones, long and weak upper lateral cartilages, thin skin, previous trauma or surgery, preoperative positive Cottle maneuver, tension nose deformity, and anteriorly positioned inferior turbinates. When any of these risk factors are identified, preventive measures should be pursued. These include preservation of middle vault support structures, judicious resection in dorsal hump reduction, use of conservative osteotomies, and reconstruction of the cartilaginous middle vault with structural grafting. Spreader grafts have become the workhorse in middle vault reconstruction. They are invaluable in restoring nasal dorsal aesthetic lines, repairing or maintaining the internal nasal valve, and buttressing a corrected crooked nose. Functional and aesthetic problems related to the middle nasal vault are among the most common reasons for patients seeking revision rhinoplasty. Although complications in rhinoplasty are inevitable, underlying their etiology and instituting prophylactic treatment can significantly help reduce their occurrence. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. [Autologous fat grafting and rhinoplasty].

    Science.gov (United States)

    Nguyen, P S; Baptista, C; Casanova, D; Bardot, J; Magalon, G

    2014-12-01

    Revision rhinoplasty can be very challenging especially in cases of thin skin. Autologous fat graft is utilized in numerous applications in plastic surgery; however, its use relative to the nasal region remains uncommon. Adipose tissue, by virtue of its volumetric qualities and its action on skin trophicity, can be considered to be a gold standard implant. From 2006 until 2012, we have treated patients by lipofilling in order to correct sequelae of rhinoplasty. The mean quantity of adipose tissue injected was 2.1cm(3) depending on the importance of the deformity and the area of injection: irregularity of the nasal dorsum, visible lateral osteotomies, saddle nose. Following the course of our practice, we conceived micro-cannulas that allow a much greater accuracy in the placement of the graft and enable to perform interventions under local anesthesia. These non-traumatic micro-cannulas do not cause post-operative ecchymosis and swelling which shorten the recovery time for the patient. On patients who have undergone multiple operations, lipofilling can be a simple and reliable alternative to correct imperfections that may take place after a rhinoplasty. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. Grafted hydroxypropyl guargum: Development, characterization and ...

    Indian Academy of Sciences (India)

    Synthesis of hydroxypropyl guargum--polyacrylamide was carried out by ceric ion induced redox polymerization technique at 28 ± 1°C. The graft copolymer was characterized by IR and thermal analysis. The flocculation performance of graft copolymer was tested in 1 wt% coal suspension.

  6. Grafted hydroxypropyl guargum: Development, characterization and ...

    Indian Academy of Sciences (India)

    Unknown

    Flocculation tests of coal fine suspension were carried out on column settling method and standard flocculation jar apparatus (supplied by M.B. Instruments, India). 3. Results and discussion. In the present investigation, two series of graft copoly- mers have been synthesized by grafting PAM onto HPG using ceric ion initiator, ...

  7. A novel initiating system for wool grafting

    Directory of Open Access Journals (Sweden)

    Magdy Kandil Zahran

    2016-05-01

    Full Text Available This paper describes a new method for the grafting of methacrylic acid (MAA and other acrylic monomers onto wool fabric in aqueous medium. The novelty principally concerns the chemical approach of the redox grafting reaction that was carried out in the presence of sodium perborate (SPB initiator. Before the grafting reaction was started, the wool fabric was treated first with a freshly prepared ferrous ammonium sulfate (FAS solution. The so-treated fabric formed, with SPB, an efficacious redox system capable of initiating grafting of methacrylic acid (MAA and other acrylic monomers onto the wool fabric. The effect of the polymerization conditions on the polymer criteria, namely, graft yield (%GY, homopolymer (%HP, total conversion (%TC, and grafting efficiency (%GE, was studied. These polymer criteria were found to depend spaciously upon concentrations of the Fe2+ ion (activator, SPB (initiator, and MAA, pH of the polymerization medium, duration and temperature of polymerization. The graft copolymerization reaction has also been carried out in the presence of polymerization activators (e.g. reductant transition metal ions and an inhibitor (e.g. hydroquinone. A suitable mechanism for the grafting processes has been suggested, in accordance with the experimental results.

  8. Oral mucosa grafts for urethral reconstruction

    African Journals Online (AJOL)

    Background: Urethral reconstruction has continued to present formidable and enormous challenges for urologic, ... reports reveal that split and full thickness skin grafts from the scrotum, penis, extragenital sites (ureter, saphenous ... Unlike other tissues, oral mucosa grafts are flexible, easy to harvest and trim and have.

  9. Graft loss after pediatric liver transplantation

    NARCIS (Netherlands)

    Sieders, E; Peeters, PMJG; TenVergert, EM; de Jong, KP; Porte, RJ; Zwaveling, JH; Bijleveld, CMA; Gouw, ASH; Slooff, MJH

    Objective To describe the epidemiology and causes of graft loss after pediatric liver transplantation and to identify risk factors. Summary Background Data Graft failure after transplantation remains an important problem. It results in patient death or retransplantation, resulting in lower survival

  10. Graft polymerization of glycidylmethacrylate onto coralline hydroxyapatite.

    Science.gov (United States)

    Murugan, R; Panduranga Rao, K

    2003-01-01

    Graft polymerization of glycidylmethacrylate (GMA) onto coralline hydroxyapatite (CHA) was carried out using potassium persulfate (K2S2O8) and sodium metabisulfite (Na2S2O5) as initiators in aqueous medium. To optimize the reaction conditions for getting maximum grafting yield, the concentrations of backbone, monomer, initiator, temperature and time were varied. The percent grafting was found to increase initially and then gradually decrease with respect to reaction parameters. The results obtained imply that the optimum temperature and time was 60 degrees C and 180 min, respectively, to obtain higher grafting yield. The grafting results have been discussed and a mechanism involved in the grafting of GMA onto CHA is described. The grafted materials were analyzed with Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) measurements. The results of FT-IR confirmed the presence of epoxy group on the grafted CHA. The XRD pattern showed that there was no secondary phase in the apatite lattice due to chemical modification.

  11. The effect of monomer molecular weight on grafting reaction

    International Nuclear Information System (INIS)

    Wu Minghong; Ding Zhongli; Ma Zueteh

    1995-01-01

    In this paper, some condensed ethylene glycol acrylate monomers with different molecular weight being grafted to the PE film by means of pre-irradiation is reported. The effect of molecular weight of monomer on grafting reaction and the hydrophilicity of grafting sample have been discussed. The experimental results show: molar degrees of grafting decreased non-linearly with the increasement of molecular weight of monomer, the grafting reaction of polymer is greater effected by the swelling degree of PE film, the greater the swelling degree of grafting material, the higher the grating degree grafting is, the initial rate of grafting reaction decreased with the increasement of molecular weight of monomer. (author)

  12. Coaxial electrospinning multicomponent functional controlled-release vascular graft: Optimization of graft properties.

    Science.gov (United States)

    Yin, Anlin; Luo, Rifang; Li, Jiukai; Mo, Xiumei; Wang, Yunbing; Zhang, Xingdong

    2017-04-01

    Small diameter vascular grafts possessing desirable biocompatibility and suitable mechanical properties have become an urgent clinic demand. Herein, heparin loaded fibrous grafts of collagen/chitosan/poly(l-lactic acid-co-ε-caprolactone) (PLCL) were successfully fabricated via coaxial electrospinning. By controlling the concentration of heparin and the ratio of collagen/chitosan/PLCL, most grafts had the heparin encapsulation efficiency higher than 70%, and the heparin presented sustained release for more than 45 days. Particularly, such multicomponent grafts had relative low initial burst release, and after heparin releasing for 3 weeks, the grafts still showed good anti-platelet adhesion ability. In addition, along with the excellent cell biocompatibility, the fabricated grafts possessed suitable mechanical properties including good tensile strength, suture retention strength, burst pressure and compliance which could well match the native blood vessels. Thus, the optimized graft properties could be properly addressed for vascular tissue application via coaxial electrospinning. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Polyethylene oxide hydration in grafted layers

    Science.gov (United States)

    Dormidontova, Elena; Wang, Zilu

    Hydration of water soluble polymers is one of the key-factors defining their conformation and properties, similar to biopolymers. Polyethylene oxide (PEO) is one of the most important biomedical-applications polymers and is known for its reverse temperature solubility due to hydrogen bonding with water. As in many practical applications PEO chains are grafted to surfaces, e.g. of nanoparticles or planar surfaces, it is important to understand PEO hydration in such grafted layers. Using atomistic molecular dynamic simulations we investigate the details of molecular conformation and hydration of PEO end-grafted to gold surfaces. We analyze polymer and water density distribution as a function of distance from the surface for different grafting densities. Based on a detailed analysis of hydrogen bonding between polymer and water in grafted PEO layers, we will discuss the extent of PEO hydration and its implication for polymer conformation, mobility and layer properties. This research is supported by NSF (DMR-1410928).

  14. Graft Take-Rates After Tympanoplasty

    DEFF Research Database (Denmark)

    Andersen, Steven Arild Wuyts; Aabenhus, Kristine; Glad, Henrik

    2014-01-01

    OBJECTIVE: To present a prospective ear surgery database and investigate the graft take-rate and prognostic factors for graft take-rate in tympanoplasty using the database. STUDY DESIGN: Prospective database study. SETTING: Tertiary referral center. PATIENTS: A total of 1606 cases undergoing...... tympanoplasty types I to IV were registered in the database in the period from February 2004 to November 2013. INTERVENTION: A total of 837 cases underwent myringoplasty/tympanoplasty type I. MAIN OUTCOME MEASURE: Graft take-rate and prognostic factors (age, discharge at time of surgery, tuba function......, technique, graft material, and revision surgery) for tympanoplasty type I were studied. A comparison with the graft take-rates for tympanoplasty types II to IV and/or cholesteatoma was made. RESULTS: A user-friendly ear surgery database with fast data entry and direct import of audiometric data...

  15. Ultraviolet light immunomodulation of canine islets for prolongation of allograft survival

    International Nuclear Information System (INIS)

    Kenyon, N.S.; Strasser, S.; Alejandro, R.

    1990-01-01

    Ultraviolet (UV) light treatment of donor islets has been shown to be effective for the prolongation of islet allograft survival in rodent models. This study evaluated UV as an immunomodulator of canine islets. The effects of UV irradiation on islet secretory function in vitro revealed a trend of increasing basal insulin release with increasing doses of UV and a corresponding significant decrease in glucose-mediated insulin release (expressed as percentage of basal fractional insulin release) beginning at UV light exposures of 200-300 J/m2 (n = 3, P less than 0.05). Proliferative responses to UV-irradiated allogeneic peripheral blood leukocytes and islets were significantly decreased by 53-112% (P less than 0.05) in 27 of 29 mixed-lymphocyte cultures and by 35-74% (P less than 0.05) in 4 of 5 mixed-lymphocyte islet culture experiments, respectively, beginning at 200-600 J/m2. Autotransplantation of nonirradiated (n = 8) and irradiated islets (600 J/m2, n = 6) resulted in a 1-mo graft survival rate of 75% for the control group and 50% for the irradiated group. Allotransplantation of irradiated islets (600 J/m2) into either nonimmunosuppressed recipients (1 donor to 1 recipient, n = 8) or recipients of subimmunosuppressive doses of cyclosporin (2 donors to 1 recipient, n = 4) resulted in 100% rejection by day 10. In contrast, when islets were cultured for 24 h postirradiation and transplanted into cyclosporin-treated pancreatectomized recipients (2 donors to 1 recipient), 3 of 7 grafts were prolonged beyond day 10 to days 16, 26, and greater than 100

  16. Angiopoietin-like protein 4 is an exercise-induced hepatokine in humans, regulated by glucagon and cAMP.

    Science.gov (United States)

    Ingerslev, Bodil; Hansen, Jakob S; Hoffmann, Christoph; Clemmesen, Jens O; Secher, Niels H; Scheler, Mika; Hrabĕ de Angelis, Martin; Häring, Hans U; Pedersen, Bente K; Weigert, Cora; Plomgaard, Peter

    2017-10-01

    Angiopoietin-like protein-4 (ANGPTL4) is a circulating protein that is highly expressed in liver and implicated in regulation of plasma triglyceride levels. Systemic ANGPTL4 increases during prolonged fasting and is suggested to be secreted from skeletal muscle following exercise. We investigated the origin of exercise-induced ANGPTL4 in humans by measuring the arterial-to-venous difference over the leg and the hepato-splanchnic bed during an acute bout of exercise. Furthermore, the impact of the glucagon-to-insulin ratio on plasma ANGPTL4 was studied in healthy individuals. The regulation of ANGPTL4 was investigated in both hepatic and muscle cells. The hepato-splanchnic bed, but not the leg, contributed to exercise-induced plasma ANGPTL4. Further studies using hormone infusions revealed that the glucagon-to-insulin ratio is an important regulator of plasma ANGPTL4 as elevated glucagon in the absence of elevated insulin increased plasma ANGPTL4 in resting subjects, whereas infusion of somatostatin during exercise blunted the increase of both glucagon and ANGPTL4. Moreover, activation of the cAMP/PKA signaling cascade let to an increase in ANGPTL4 mRNA levels in hepatic cells, which was prevented by inhibition of PKA. In humans, muscle ANGPTL4 mRNA increased during fasting, with only a marginal further induction by exercise. In human muscle cells, no inhibitory effect of AMPK activation could be demonstrated on ANGPTL4 expression. The data suggest that exercise-induced ANGPTL4 is secreted from the liver and driven by a glucagon-cAMP-PKA pathway in humans. These findings link the liver, insulin/glucagon, and lipid metabolism together, which could implicate a role of ANGPTL4 in metabolic diseases. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  17. Recent Advances in the Development of Antimicrobial Peptides (AMPs): Attempts for Sustainable Medicine?

    Science.gov (United States)

    Kokel, Anne; Torok, Marianna

    2018-01-17

    Since the first isolation of antimicrobial peptides (AMPs) they have attracted extensive interest in medicinal chemistry. However, only a few AMP-based drugs are currently available on the market. Despite their effectiveness, biodegradability, and versatile mode of action that is less likely to induce resistance compared to conventional antibiotics, AMPs suffer from major issues that need to be addressed to broaden their use. Notably, AMPs can lack selectivity leading to side effects and cytotoxicity, and also exhibit in vivo instability. Several strategies are being actively considered to overcome the limitations that restrain the success of AMPs. In the current work, recent strategies reported for improving AMPs in the context of drug design and delivery were surveyed, and also their possible impact on patients and the environment was assessed. As a major advantage AMPs possess an easily tunable skeleton offering opportunities to improve their properties. Strategic structural modifications and the beneficial properties of cyclic or branched AMPs in term of stability have been reported. The conjugation of AMPs with nanoparticles has also been explored to increase their in vivo stability. Other techniques such as the coupling of AMPs with specific antibodies aim to increase the selectivity of the potential drug towards the target. These strategies were evaluated for their effect on the environment highlighting green technologies. Although further research is needed taking into account both environmental and human health consequences of novel AMPs several of these compounds are promising drug candidates for use in sustainable medicine. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Genetically-encoded tools for cAMP probing and modulation in living systems.

    Directory of Open Access Journals (Sweden)

    Valeriy M Paramonov

    2015-09-01

    Full Text Available Intracellular 3'-5'-cyclic adenosine monophosphate (cAMP is one of the principal second messengers downstream of a manifold of signal transduction pathways, including the ones triggered by G protein-coupled receptors. Not surprisingly, biochemical assays for cAMP have been instrumental for basic research and drug discovery for decades, providing insights into cellular physiology and guiding pharmaceutical industry. However, despite impressive track record, the majority of conventional biochemical tools for cAMP probing share the same fundamental shortcoming - all the measurements require sample disruption for cAMP liberation. This common bottleneck, together with inherently low spatial resolution of measurements (as cAMP is typically analyzed in lysates of thousands of cells, underpin the ensuing limitations of the conventional cAMP assays: 1 genuine kinetic measurements of cAMP levels over time in a single given sample are unfeasible; 2 inability to obtain precise information on cAMP spatial distribution and transfer at subcellular levels, let alone the attempts to pinpoint dynamic interactions of cAMP and its effectors. At the same time, tremendous progress in synthetic biology over the recent years culminated in drastic refinement of our toolbox, allowing us not only to bypass the limitations of conventional assays, but to put intracellular cAMP life-span under tight control – something, that seemed scarcely attainable before. In this review article we discuss the main classes of modern genetically-encoded tools tailored for cAMP probing and modulation in living systems. We examine the capabilities and weaknesses of these different tools in the context of their operational characteristics and applicability to various experimental set-ups involving living cells, providing the guidance for rational selection of the best tools for particular needs.

  19. Migraine with prolonged aura: phenotype and treatment.

    Science.gov (United States)

    Viana, Michele; Afridi, Shazia

    2018-01-01

    We review the published literature on migraine with prolonged aura (PA), specifically with regards to the phenotype and treatment options. PA is not uncommon. A recent study found that about 17% of migraine auras are prolonged and that 26% of patients with migraine with aura have experienced at least one PA. The characteristics of PA are similar to most typical auras with the exception of a higher number of aura symptoms (in particular sensory and/or dysphasic). There are no well-established treatments at present which target the aura component of migraine. Other than case reports, there have been open-label studies of lamotrigine and greater occipital nerve blocks. The only randomised, blinded, controlled trial to date has been of nasal ketamine showing some reduction in aura severity but not duration. A small open-labelled pilot study of amiloride was also promising. Larger randomised, controlled trials are needed to establish whether any of the existing or novel compounds mentioned are significantly effective and safe.

  20. Upper thymic prolongation simulating mediastinal lymphadenomegaly

    Directory of Open Access Journals (Sweden)

    Cristiane Wosny

    2009-09-01

    Full Text Available The thymus is located in the anterior portion of the upper mediastinum, immediately behind the sternal manubrium, and extends to the anterior mediastinum, anteriorly to the pericardium. Two patients were evaluated due to nodulations at the transition from the cervical region to the anterior mediastinum, which simulated lymphadenomegaly. The first patient, a seven-year-old male, presented with a rhabdomyosarcoma of the masticatory space; during progressive follow-up, a nodule was noted with FDG uptake on the positron emission tomography coupled with the computed tomography (PET-CT. The second patient, a 51-year-old female, presented with a nodulation characterized on the magnetic resonance image for follow-up of a papilliferous carcinoma of the thyroid. In both cases, the nodulation displayed an upper prolongation of the thymus. These nodulations showed the same density on the computed tomography and the same signal intensity on the magnetic resonance image as the adjacent thymic tissue, and there was no adipose tissue layer between the nodulations and the thymus. Knowledge of the upper prolongation of the thymus as an anatomical variation is vital for differentiating it from mediastinal lymphadenomegaly, thus avoiding unnecessary biopsies or procedures.

  1. Role of tacrolimus prolonged release in the prevention of allograft rejection

    Directory of Open Access Journals (Sweden)

    Peter Abrams

    2010-08-01

    Full Text Available Peter Abrams, Abhinav Humar, Henkie P TanDepartment of Surgery, Thomas E Starzl Transplantation Institute, University of Pittsburgh School of Medicine, Pennsylvania, USAAbstract: Successful management of the solid-organ transplant recipient begins with prevention of rejection and achieving a balance between insufficient and excessive immunosuppression. Standard tacrolimus therapy for prevention of solid-organ transplant rejection consists of 2 divided doses per day. In an effort to simplify tacrolimus dosing to once daily, a new formulation (tacrolimus prolonged release [PR] was chosen for its combination of a similar extent of bioavailability and a substantially reduced rate of clearance. Several clinical conversion studies have now been completed using PR to clarify its pharmacokinetics, efficacy at prevention of allograft rejection, and safety profiles in solid-organ transplant patients. A cohort of 67 stable kidney transplant recipients was converted from standard tacrolimus to PR in an open-label, multicenter study in the United States and Canada. A second open-label, multicenter study was performed in liver transplant recipients with stable graft function on standard tacrolimus therapy converted to PR. A third conversion study was performed as an open-label study at 5 centers in the United States in stable pediatric liver transplant recipients. As medication noncompliance can significantly contribute to the incidence of graft rejection and graft loss in transplant recipients, a potentially significant advance in the transplant community’s ongoing mission to optimize prevention of rejection occurred with the development of a once-daily tacrolimus PR. The results of these preliminary studies suggest that select solid-organ transplant recipients converted to PR can be safely maintained using the same monitoring and patient care techniques historically used for standard tacrolimus therapy.Keywords: immunosuppression, tacrolimus allograft

  2. The Pseudomonas aeruginosa Chp Chemosensory System Regulates Intracellular cAMP Levels by Modulating Adenylate Cyclase Activity

    Science.gov (United States)

    Fulcher, Nanette B.; Holliday, Phillip M.; Klem, Erich; Cann, Martin J.; Wolfgang, Matthew C.

    2010-01-01

    Summary Multiple virulence systems in the opportunistic pathogen Pseudomonas aeruginosa are regulated by the second messenger signaling molecule adenosine 3’, 5’-cyclic monophosphate (cAMP). Production of cAMP by the putative adenylate cyclase enzyme CyaB represents a critical control point for virulence gene regulation. To identify regulators of CyaB, we screened a transposon insertion library for mutants with reduced intracellular cAMP. The majority of insertions resulting in reduced cAMP mapped to the Chp gene cluster encoding a putative chemotaxis-like chemosensory system. Further genetic analysis of the Chp system revealed that it has both positive and negative effects on intracellular cAMP and that it regulates cAMP levels by modulating CyaB activity. The Chp system was previously implicated in the production and function of type IV pili (TFP). Given that cAMP and the cAMP-dependent transcriptional regulator Vfr control TFP biogenesis gene expression, we explored the relationship between cAMP, the Chp system and TFP regulation. We discovered that the Chp system controls TFP production through modulation of cAMP while control of TFP-dependent twitching motility is cAMP-independent. Overall, our data define a novel function for a chemotaxis-like system in controlling cAMP production and establish a regulatory link between the Chp system, TFP and other cAMP-dependent virulence systems. PMID:20345659

  3. AICA-riboside (acadesine), an activator of AMP-activated protein kinase with potential for application in hematologic malignancies.

    Science.gov (United States)

    Van Den Neste, Eric; Van den Berghe, Georges; Bontemps, Françoise

    2010-04-01

    Despite considerable advances, B-cell chronic lymphocytic leukemia (CLL) is incurable with standard approaches. Thus, there remains a need for new therapies, particularly for patients who develop chemoresistance to DNA-targeting treatments. AICA-riboside (acadesine) is a nucleoside with a wide range of metabolic effects, including release of adenosine and activation of AMP-activated protein kinase (AMPK), which was initially developed as a cardioprotective agent. More recently, it has been shown that AICA-riboside induces apoptosis in various models of leukemia, including CLL. The literature data show that apoptosis induced by AICA-riboside in CLL is not dependent on a functionally normal p53 pathway. Moreover, AICA-riboside is active towards resting and proliferative models of leukemia cells, including resistant phenotypes. Finally, studies in healthy subjects and during coronary artery bypass graft surgery show that AICA-riboside is devoid of serious toxicity. This paper reviews the mechanisms of action of AICA-riboside in normal and malignant cells and discusses how AICA-riboside could impact CLL treatment. We propose that AICA-riboside, which displays a relative selectivity and a favorable toxicity profile, may offer a new treatment option for CLL.

  4. The Racial Paradox in Multiarterial Conduit Utilization for Coronary Artery Bypass Grafting.

    Science.gov (United States)

    Keeling, W Brent; Binongo, Jose; Halkos, Michael E; Leshnower, Bradley G; Nguyen, Duc Q; Chen, Edward P; Sarin, Eric L; Miller, Jeffrey S; Macheers, Steven; Lattouf, Omar M; Guyton, Robert A; Thourani, Vinod H

    2017-04-01

    It has been established that outcomes for black patients undergoing coronary artery bypass graft surgery (CABG) are inferior to those of their white counterparts. The purpose of this study was to determine (1) whether rates of multiarterial grafting are different among black patients and white patients, and (2) whether racial differences exist in postoperative outcomes after accounting for grafting strategy. A retrospective review of black patients (n = 2,810) and white patients (n = 13,569) who underwent isolated, primary CABG from January 2002 to June 2014 at a US academic institution was performed. A modified predicted risk of mortality (M-PROM) score was calculated for each patient using all The Society of Thoracic Surgeons variables for CABG excluding race. Multivariable linear, logistic, and Cox regression analyses were used to assess between-group differences, adjusted for M-PROM. Overall, 16,379 patients underwent CABG, and 2,441 (14.9%) received more than one arterial graft. When adjusted for M-PROM, the odds of blacks undergoing multiarterial CABG were 10% greater than for whites (p = 0.05). Blacks had worse inhospital outcomes, including higher odds of stroke (odds ratio 2.41, 95% confidence interval [CI]: 1.80 to 3.25) and prolonged intubation (odds ratio 2.01, 95% CI: 1.77 to 2.28). The increase in postoperative complications did not translate to a difference in inhospital mortality (p = 0.10) between racial cohorts. Moreover, among patients who underwent multiarterial grafting strategies, blacks had a hazard of mortality that was 34% higher (95% CI: 22% to 51%)) than that of their white counterparts. Among black patients, those who underwent multiarterial grafting strategies showed better long-term survival than those undergoing single grafting strategies (hazard ratio 0.86, 95% CI: 0.78 to 0.96). Despite similar rates of arterial grafting for black patients and white patients in this large single-center cohort, black patients continued to have

  5. A Temporal-Specific and Transient cAMP Increase Characterizes Odorant Classical Conditioning

    Science.gov (United States)

    Cui, Wen; Smith, Andrew; Darby-King, Andrea; Harley, Carolyn W.; McLean, John H.

    2007-01-01

    Increases in cyclic adenosine monophosphate (cAMP) are proposed to initiate learning in a wide variety of species. Here, we measure changes in cAMP in the olfactory bulb prior to, during, and following a classically conditioned odor preference trial in rat pups. Measurements were taken up to the point of maximal CREB phosphorylation in olfactory…

  6. Model development and process simulation of postcombustion carbon capture technology with aqueous AMP/PZ solvent

    NARCIS (Netherlands)

    van der Spek, Mijndert; Arendsen, Richard; Ramirez, Andrea; Faaij, André

    2016-01-01

    This study presents the development, application, and uncertainty analysis of a process simulation model for postcombustion CO2 capture with an AMP/PZ solvent blend based on state of the art knowledge on AMP/PZ solvent technology. The development includes the improvement of the physical property

  7. N6-Methyl-AMP aminohydrolase activates N6-substituted purine acyclic nucleoside phosphonates

    Czech Academy of Sciences Publication Activity Database

    Schinkmanová, Markéta; Votruba, Ivan; Holý, Antonín

    2006-01-01

    Roč. 71, č. 9 (2006), s. 1370-1376 ISSN 0006-2952 R&D Projects: GA AV ČR(CZ) 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : N6-methyl- AMP aminohydrolase * me- AMP * cypr-PMEDAP * PMEG Subject RIV: CC - Organic Chemistry Impact factor: 3.581, year: 2006

  8. The cAMP Signaling and MAP Kinase Pathways in Plant Pathogenic Fungi

    NARCIS (Netherlands)

    Mehrabi, R.; Zhao, X.; Kim, Y.; Xu, J.R.

    2009-01-01

    The key components of the well conserved cyclic AMP signaling and MAP kinase pathways have been functionally characterized in the corn smut Ustilago maydis, rice blast fungus Magnaporthe grisea, and a few other fungal pathogens. In general, the cAMP signaling and the MAP kinase cascade homologous to

  9. The effect of mutations in the AmpC promoter region on β-lactam ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-08-04

    Aug 4, 2008 ... lactamase gene can result in AmpC hyper-production. (Martinez-Martinez et al., 2000). Such hyper-production of AmpC β-lactamase contributes to resistance to ampi- cillin, extended-spectrum cephalosporins and β-lactam-β- lactamase inhibitor combinations (Martinez-Martinez et. *Corresponding author: ...

  10. Design of cAMP-CRP-activated promoters in Escherichia coli

    DEFF Research Database (Denmark)

    Valentin-Hansen, P; Holst, B; Søgaard-Andersen, L

    1991-01-01

    We have studied the deoP2 promoter of Escherichia coli to define features that are required for optimal activation by the complex of adenosine 3',5' monophosphate (cAMP) and the cAMP receptor protein (CRP). Systematic mutagenesis of deoP2 shows that the distance between the CRP site and the -10...

  11. Global and local missions of cAMP signaling in neural plasticity, learning, and memory.

    Science.gov (United States)

    Lee, Daewoo

    2015-01-01

    The fruit fly Drosophila melanogaster has been a popular model to study cAMP signaling and resultant behaviors due to its powerful genetic approaches. All molecular components (AC, PDE, PKA, CREB, etc) essential for cAMP signaling have been identified in the fly. Among them, adenylyl cyclase (AC) gene rutabaga and phosphodiesterase (PDE) gene dunce have been intensively studied to understand the role of cAMP signaling. Interestingly, these two mutant genes were originally identified on the basis of associative learning deficits. This commentary summarizes findings on the role of cAMP in Drosophila neuronal excitability, synaptic plasticity and memory. It mainly focuses on two distinct mechanisms (global versus local) regulating excitatory and inhibitory synaptic plasticity related to cAMP homeostasis. This dual regulatory role of cAMP is to increase the strength of excitatory neural circuits on one hand, but to act locally on postsynaptic GABA receptors to decrease inhibitory synaptic plasticity on the other. Thus the action of cAMP could result in a global increase in the neural circuit excitability and memory. Implications of this cAMP signaling related to drug discovery for neural diseases are also described.

  12. Surface-Enhanced Raman Scattering of the Complexes of Silver with Adenine and dAMP

    NARCIS (Netherlands)

    Otto, Cornelis; Hoeben, F.P.; Hoeben, F.P.; Greve, Jan

    1991-01-01

    The behaviour of adenine and 2'-deoxyadenosine-5'-monophosphate (dAMP) at positive surface potentials of a silver working electrode was investigated using surface-enhanced Raman scattering (SERS). The use of positive potentials in the presence of adenine or dAMP leads to a rapid accumulation of an

  13. Acquisition of carbapenem resistance by plasmid-encoded-AmpC-expressing Escherichia coli

    NARCIS (Netherlands)

    Tommassen - van Boxtel, Ria; Wattel, Agnes A.; Arenas Busto, Jesus; Goessens, Wil H.F.; Tommassen, J

    2017-01-01

    Although AmpC β-lactamases can barely degrade carbapenems, if at all, they can sequester them and prevent them from reaching their targets. Thus, carbapenem resistance in Escherichia coli and other Enterobacteriaceae can result from AmpC production and simultaneous reduction of antibiotic influx

  14. The Cyclic Nucleotide Specificity of Three cAMP Receptors in Dictyostelium

    NARCIS (Netherlands)

    Johnson, Ronald L.; Haastert, Peter J.M. van; Kimmel, Alan R.; Saxe III, Charles L.; Jastorff, Bernd; Devreotes, Peter N.

    1992-01-01

    cAMP receptors mediate signal transduction pathways during development in Dictyostelium. A cAMP receptor (cAR1) has been cloned and sequenced (Klein, P., Sun, T. J., Saxe, C. L., Kimmel, A. R., Johnson, R. L., and Devreotes, P. N. (1988) Science 241, 1467-1472) and recently several other cAR genes

  15. Targeting brain tumor cAMP: the case for sex-specific therapeutics

    Directory of Open Access Journals (Sweden)

    Nicole M Warrington

    2015-07-01

    Full Text Available A relationship between cyclic adenosine 3’, 5’-monophosphate (cAMP levels and brain tumor biology has been evident for nearly as long as cAMP and its synthetase, adenylate cyclase (ADCY have been known. The importance of the pathway in brain tumorigenesis has been demonstrated in vitro and in multiple animal models. Recently, we provided human validation for a cooperating oncogenic role for cAMP in brain tumorigenesis when we found that SNPs in ADCY8 were correlated with glioma (brain tumor risk in individuals with Neurofibromatosis type 1 (NF1. Together, these studies provide a strong rationale for targeting cAMP in brain tumor therapy. However, the cAMP pathway is well known to be sexually dimorphic, and SNPs in ADCY8 affected glioma risk in a sex-specific fashion, elevating the risk for females while protecting males. The cAMP pathway can be targeted at multiple levels in the regulation of its synthesis and degradation. Sex differences in response to drugs that target cAMP regulators indicate that successful targeting of the cAMP pathway for brain tumor patients is likely to require matching specific mechanisms of drug action with patient sex.

  16. Dibutyryl c-AMP as an inducer of sporidia formation: Biochemical ...

    Indian Academy of Sciences (India)

    ... however, increasing concentration of dbc-AMP was deleterious to mycelial growth in liquid culture. A slow increase of mycelial biomass up to 21 days and decline at 30 days in the presence of 2.5 mM dbc-AMP was observed, therefore, this concentration was chosen in subsequent investigations. The inhibitory influence ...

  17. Cyclic AMP signaling restricts activation and promotes maturation and antioxidant defenses in astrocytes.

    Science.gov (United States)

    Paco, Sonia; Hummel, Manuela; Plá, Virginia; Sumoy, Lauro; Aguado, Fernando

    2016-04-23

    cAMP signaling produces dramatic changes in astrocyte morphology and physiology. However, its involvement in phenotype acquisition and the transcriptionally mediated mechanisms of action are largely unknown. Here we analyzed the global transcriptome of cultured astroglial cells incubated with activators of cAMP pathways. A bulk of astroglial transcripts, 6221 annotated genes, were differentially regulated by cAMP signaling. cAMP analogs strongly upregulated genes involved in typical functions of mature astrocytes, such as homeostatic control, metabolic and structural support to neurons, antioxidant defense and communication, whereas they downregulated a considerable number of proliferating and immaturity-related transcripts. Moreover, numerous genes typically activated in reactive cells, such as scar components and immunological mediators, were repressed by cAMP. GSEA analysis contrasting gene expression profiles with transcriptome signatures of acutely isolated astrocytes and in situ evaluation of protein levels in these cells showed that cAMP signaling conferred mature and in vivo-like transcriptional features to cultured astrocytes. These results indicate that cAMP signaling is a key pathway promoting astrocyte maturation and restricting their developmental and activation features. Therefore, a positive modulation of cAMP signaling may promote the normal state of differentiated astrocytes and favor the protection and function of neuronal networks.

  18. Occurrence and detection of AmpC β-lactamases among ...

    African Journals Online (AJOL)

    Soha A. El-Hady

    2015-04-06

    Apr 6, 2015 ... b-lactam antibiotics except cefepime and carbapenems. Aim of the study: We aimed to ... Subjects and methods: 50 AmpC b-lactamase Enterobacteriaceae were analyzed for the presence of AmpC production. ... The prevalence of multidrug-resistant Gram-negative bacteria has increased continuously over ...

  19. Prevalence of AmpC β-lactamase among Gram-negative bacteria ...

    African Journals Online (AJOL)

    Purpose: Infections caused by AmpC-positive bacteria results in high patient morbidity and mortality making their detection clinically important as they cannot be detected in routine susceptibility testing. This study aim to determine the prevalence of AmpC β-lactamase among Gram negative bacteria recovered from clinical ...

  20. Amp: A modular approach to machine learning in atomistic simulations

    Science.gov (United States)

    Khorshidi, Alireza; Peterson, Andrew A.

    2016-10-01

    Electronic structure calculations, such as those employing Kohn-Sham density functional theory or ab initio wavefunction theories, have allowed for atomistic-level understandings of a wide variety of phenomena and properties of matter at small scales. However, the computational cost of electronic structure methods drastically increases with length and time scales, which makes these methods difficult for long time-scale molecular dynamics simulations or large-sized systems. Machine-learning techniques can provide accurate potentials that can match the quality of electronic structure calculations, provided sufficient training data. These potentials can then be used to rapidly simulate large and long time-scale phenomena at similar quality to the parent electronic structure approach. Machine-learning potentials usually take a bias-free mathematical form and can be readily developed for a wide variety of systems. Electronic structure calculations have favorable properties-namely that they are noiseless and targeted training data can be produced on-demand-that make them particularly well-suited for machine learning. This paper discusses our modular approach to atomistic machine learning through the development of the open-source Atomistic Machine-learning Package (Amp), which allows for representations of both the total and atom-centered potential energy surface, in both periodic and non-periodic systems. Potentials developed through the atom-centered approach are simultaneously applicable for systems with various sizes. Interpolation can be enhanced by introducing custom descriptors of the local environment. We demonstrate this in the current work for Gaussian-type, bispectrum, and Zernike-type descriptors. Amp has an intuitive and modular structure with an interface through the python scripting language yet has parallelizable fortran components for demanding tasks; it is designed to integrate closely with the widely used Atomic Simulation Environment (ASE), which

  1. Evaluation of synthetic vascular grafts in a mouse carotid grafting model.

    Directory of Open Access Journals (Sweden)

    Alex H P Chan

    Full Text Available Current animal models for the evaluation of synthetic grafts are lacking many of the molecular tools and transgenic studies available to other branches of biology. A mouse model of vascular grafting would allow for the study of molecular mechanisms of graft failure, including in the context of clinically relevant disease states. In this study, we comprehensively characterise a sutureless grafting model which facilitates the evaluation of synthetic grafts in the mouse carotid artery. Using conduits electrospun from polycaprolactone (PCL we show the gradual development of a significant neointima within 28 days, found to be greatest at the anastomoses. Histological analysis showed temporal increases in smooth muscle cell and collagen content within the neointima, demonstrating its maturation. Endothelialisation of the PCL grafts, assessed by scanning electron microscopy (SEM analysis and CD31 staining, was near complete within 28 days, together replicating two critical aspects of graft performance. To further demonstrate the potential of this mouse model, we used longitudinal non-invasive tracking of bone-marrow mononuclear cells from a transgenic mouse strain with a dual reporter construct encoding both luciferase and green fluorescent protein (GFP. This enabled characterisation of mononuclear cell homing and engraftment to PCL using bioluminescence imaging and histological staining over time (7, 14 and 28 days. We observed peak luminescence at 7 days post-graft implantation that persisted until sacrifice at 28 days. Collectively, we have established and characterised a high-throughput model of grafting that allows for the evaluation of key clinical drivers of graft performance.

  2. Early postoperative angiographic assessment of radial grafts used for coronary artery bypass grafting.

    Science.gov (United States)

    Chen, A H; Nakao, T; Brodman, R F; Greenberg, M; Charney, R; Menegus, M; Johnson, M; Grose, R; Frame, R; Hu, E C; Choi, H K; Safyer, S

    1996-06-01

    Despite a revival of interest in using the radial artery as an alternative conduit for myocardial revascularization, little angiographic documentation of early postoperative results has been presented, particularly in North America. Accordingly, 60 of 150 patients who underwent coronary artery bypass with radial arteries from November 1993 to July 1995 have had postoperative cardiac catheterization at our institution. The patency rate of the radial artery grafts was 95.7% (90 of 94 grafts patent) with an average internal diameter of 2.51 mm. Four radial artery grafts showed diffuse narrowing. The patency rate of the internal thoracic artery grafts was 100% with an average internal diameter of 2.25 mm. Three of 62 grafts demonstrated diffuse narrowing. Two of 24 (7.7%) saphenous vein grafts were occluded; the average internal diameter was 3.23 mm. The internal thoracic artery, the radial artery, and saphenous vein grafts were, respectively, 7.5%, 19.5%, and 53.3% larger than the anastomosed native coronary arteries. Graft-dependent flow was found in 81.1% of the radial artery grafts. The results of this study demonstrate that the short-term patency rate of radial artery grafts is excellent.

  3. The 2013 German-Russian Bion-M1 Joint Flight Project: Altered cAMP/PKA Signaling Pathway in Skeletal Muscle during Exposure to Real Microgravity in Mice Housed for 30 Days in a Biosatellite on Orbit

    Science.gov (United States)

    Salanova, Michele; Blottner, Dieter; Shenkman, Boris S.; Lomonosova, Yulia

    Exposure to real microgravity (muG) results in an impaired skeletal muscle structure and function. We here hypothesized that the cAMP/PKA cell signaling pathway, which triggers a multitude of intracellular effects in response to a variety of extracellular stimuli and which further promote muscle growth, play an important role during Spaceflight- induced disuse atrophy. Particularly, we hypothesized that different effectors of the cAMP-PKA signaling machinery, which are highly compartmentalized into subcellular functional microdomains in order to guarantee signal specificity, are altered after long term exposure to real µG. Taking advantage of the Bion-M1 Spaceflight program which provided us an excellent opportunity to explore mice skeletal muscle exposed for 30 days to real µG, by investigating at the cAMP-dependent protein kinase A (PKA) subcellular localization we compared muscle soleus (SOL) and extensor digitorum longus (EDL) of C57/black mice of a Bion-flight (n=5) group with a Bion-ground control (n=5) group and a ground control (n=5) group which was housed in a standard cage considered as vivarium control. Preliminary results of our experiments showed that different cAMP-PKA micro pools were normally detectable using high-resolution images of immunofluorescence experiments in different subcellular compartments of both SOL and EDL of Bion-ground and ground control groups which were not any longer detectable in Bion-flight group. In summary, our data indicate that an efficient organization in microdomains of the cAMP/PKA pathway may exist in skeletal muscle on ground and that such compartmentalization may be altered in response to prolonged exposure to real muG. National Sponsors: Federal Ministry of Economics and Technology (BMWi) via the German AeroSpace Board, DLR e.V., Bonn-Oberkassel, Germany (#50WB1121 to DB); Contract RAS-IMPB/Charité Berlin # Bion-M1/2013

  4. cAMP prevents TNF-induced apoptosis through inhibiting DISC complex formation in rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, Rajesh [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States); Xiang, Wenpei [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States); Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People' s Republic of China (China); Wang, Yinna [Vascular Medicine Institute, University of Pittsburgh School of Medicine, 10051-5A BST 3, 3501 Fifth Avenue, Pittsburgh, PA 15261 (United States); Zhang, Xiaoying [Department of Medicine/Endocrinology Division, University of Pittsburgh Medical Center, 200 Lothrop St., Pittsburgh, PA 15213 (United States); Billiar, Timothy R., E-mail: billiartr@upmc.edu [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213 (United States)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer cAMP blocks cell death induced by TNF and actinomycin D in cultured hepatocytes. Black-Right-Pointing-Pointer cAMP blocks NF-{kappa}B activation induced by TNF and actinomycin D. Black-Right-Pointing-Pointer cAMP blocks DISC formation following TNF and actinomycin D exposure. Black-Right-Pointing-Pointer cAMP blocks TNF signaling at a proximal step. -- Abstract: Tumor necrosis factor {alpha} (TNF) is a pleiotropic proinflammatory cytokine that plays a role in immunity and the control of cell proliferation, cell differentiation, and apoptosis. The pleiotropic nature of TNF is due to the formation of different signaling complexes upon the binding of TNF to its receptor, TNF receptor type 1 (TNFR1). TNF induces apoptosis in various mammalian cells when the cells are co-treated with a transcription inhibitor like actinomycin D (ActD). When TNFR1 is activated, it recruits an adaptor protein, TNF receptor-associated protein with death domain (TRADD), through its cytoplasmic death effector domain (DED). TRADD, in turn, recruits other signaling proteins, including TNF receptor-associated protein 2 (TRAF2) and receptor-associated protein kinase (RIPK) 1, to form a complex. Subsequently, this complex combines with FADD and procaspase-8, converts into a death-inducing signaling complex (DISC) to induce apoptosis. Cyclic AMP (cAMP) is a second messenger that regulates various cellular processes such as cell proliferation, gene expression, and apoptosis. cAMP analogues are reported to act as anti-apoptotic agents in various cell types, including hepatocytes. We found that a cAMP analogue, dibutyryl cAMP (db-cAMP), inhibits TNF + ActD-induced apoptosis in rat hepatocytes. The protein kinase A (PKA) inhibitor KT-5720 reverses this inhibitory effect of cAMP on apoptosis. Cytoprotection by cAMP involves down-regulation of various apoptotic signal regulators like TRADD and FADD and inhibition of caspase-8 and caspase-3 cleavage. We also found

  5. Cyclic AMP activates the mitogen-activated protein kinase cascade in PC12 cells

    DEFF Research Database (Denmark)

    Frödin, M; Peraldi, P; Van Obberghen, E

    1994-01-01

    Mitogen-activated protein (MAP) kinases are activated in response to a large variety of extracellular signals, including growth factors, hormones, and neurotransmitters, which activate distinct intracellular signaling pathways. Their activation by the cAMP-dependent pathway, however, has not been...... reported. In rat pheochromocytoma PC12 cells, we demonstrate here a stimulation of the MAP kinase isozyme extracellular signal-regulated kinase 1 (ERK1) following elevation of intracellular cAMP after exposure of the cells to isobutylmethylxanthine, cholera toxin, forskolin, or cAMP-analogues. cAMP acted...... synergistically with phorbol ester, an activator of protein kinase C, in the stimulation of ERK1. In accordance with this observation, the peptide neurotransmitter pituitary adenylate cyclase-activating polypeptide 38 (PACAP38), which stimulates cAMP production as well as phosphatidylinositol breakdown in PC12...

  6. The effect of in vitro procedures on cyclic AMP accumulation in human leucocytes

    DEFF Research Database (Denmark)

    Johansen, Torben; Friis, U G; Rasmussen, A K

    1994-01-01

    The aim of this study was to investigate the effect of various methodological procedures or protocols on cyclic AMP formation in human leucocytes. The data showed that: (1) ATP content and lactate production was unaffected by hypotonic lysis during leucocyte isolation; (2) there was a linear...... relation between cell number/sample and the production of cyclic adenosine 3':5'-monophosphate (cAMP); (3) the interindividual variation markedly affected cAMP production during long observation periods (years), whereas day-to-day variation within a week was less important; (4) whole blood could be stored...... for up to 4 h (at 4 degrees C or 23 degrees C) without affecting cAMP accumulation; (5) isolated MNL could be stored for up to 2 h (at 4 degrees C) without affecting cAMP accumulation; and finally that (6) choice and concentration of phosphodiesterase inhibitors markedly influenced the basal...

  7. Cyclic AMP activates the mitogen-activated protein kinase cascade in PC12 cells

    DEFF Research Database (Denmark)

    Frödin, M; Peraldi, P; Van Obberghen, E

    1994-01-01

    reported. In rat pheochromocytoma PC12 cells, we demonstrate here a stimulation of the MAP kinase isozyme extracellular signal-regulated kinase 1 (ERK1) following elevation of intracellular cAMP after exposure of the cells to isobutylmethylxanthine, cholera toxin, forskolin, or cAMP-analogues. cAMP acted...... upstream activator of ERK1 in the MAP kinase cascade. Supporting this view, forskolin and a cAMP analogue were found to increase the activity of MAP kinase kinase in PC12 cells, alone as well as in combination with phorbol ester. PACAP38 also stimulated in vivo 32P-labeling of ERK1 and MAP kinase kinase...... activity. Finally, cAMP or PACAP38 increased by 3-fold nerve growth factor-stimulated neurite formation in PC12 cells, which may be correlated with the potentiating effect of these agents on nerve growth factor-stimulated ERK1 activity....

  8. Role of AC-cAMP-PKA Cascade in Antidepressant Action of Electroacupuncture Treatment in Rats

    Directory of Open Access Journals (Sweden)

    Jian-hua Liu

    2012-01-01

    Full Text Available Adenylyl cyclase (AC-cyclic adenosine monophosphate (cAMP-cAMP-dependent protein kinase A (PKA cascade is considered to be associated with the pathogenesis and treatment of depression. The present study was conducted to explore the role of the cAMP cascade in antidepressant action of electroacupuncture (EA treatment for chronic mild stress (CMS-induced depression model rats. The results showed that EA improved significantly behavior symptoms in depression and dysfunction of AC-cAMP-PKA signal transduction pathway induced by CMS, which was as effective as fluoxetine. Moreover, the antidepressant effects of EA rather than Fluoxetine were completely abolished by H89, a specific PKA inhibitor. Consequently, EA has a significant antidepressant treatment in CMS-induced depression model rats, and AC-cAMP-PKA signal transduction pathway is crucial for it.

  9. Cyclic AMP response in cells exposed to electric fields of different frequencies and intensities

    Energy Technology Data Exchange (ETDEWEB)

    Knedlitschek, G. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie; Noszvai-Nagy, M. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie; Meyer-Waarden, H. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie; Schimmelpfeng, J. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie; Weibezahn, K.F. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie; Dertinger, H. [Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Toxikologie

    1994-04-01

    The action on intracellular cyclic AMP (cAMP) of therapeutically used 4000-Hz electric fields was investigated and compared with 50-Hz data. Cultured mouse fibroblasts were exposed for 5 minutes to 4000-Hz sine wave internal electric fields between 3 mV/m and 30 V/m applied within culture medium. A statistically significant decrease in cellular cAMP concentration relative to unexposed cells was observed for fields higher than 10 mV/m. The drop in cAMP was ost pronounced at lower field strengths (71% of controls at 30 mV/m) and tended to disappear at higher field strengths. An increase of cAMP content was observed with 50-Hz electric fields, as was also the case when 4000-Hz fields were modulated with certain low frequencies. (orig.)

  10. AMP-Conjugated Quantum Dots: Low Immunotoxicity Both In Vitro and In Vivo

    Science.gov (United States)

    Dai, Tongcheng; Li, Na; Liu, Lu; Liu, Qin; Zhang, Yuanxing

    2015-11-01

    Quantum dots (QDs) are engineered nanoparticles that possess special optical and electronic properties and have shown great promise for future biomedical applications. In this work, adenosine 5'-monophosphate (AMP), a small biocompatible molecular, was conjugated to organic QDs to produce hydrophilic AMP-QDs. Using macrophage J774A.1 as the cell model, AMP-QDs exhibited both prior imaging property and low toxicity, and more importantly, triggered limited innate immune responses in macrophage, indicating low immunotoxicity in vitro. Using BALB/c mice as the animal model, AMP-QDs were found to be detained in immune organs but did not evoke robust inflammation responses or obvious histopathological abnormalities, which reveals low immunotoxicity in vivo. This work suggests that AMP is an excellent surface ligand with low immunotoxicity, and potentially used in surface modification for more extensive nanoparticles.

  11. PROLONGED MASSIVE POLYURIA AFTER RENAL TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    A. M. Chernyavskiy

    2012-01-01

    Full Text Available Clinical case of prolonged massive polyuria in patient after renal transplantation is represented in this article. Polyuria lasted for a forty days after kidney transplantation, the larges amount of urine output was 55 litres per day. Analysis of transplant biopsy revealed acute tubular necrosis, initial arteriolosclerosis and suspected acute rejection. Doppler ultrasound study and perfusion scintigraphy detected no pathology. At first we tried to decrease the volume of infusion and fluid intake. Also we performed pulse therapy with methylprednisolone. However, these efforts were not effective. Using of a large doses of «Minerin» (posterior pituitary antidiuretic factor allowed to decrease and stabilize the volume of urine output. The patient was discharge from clinic on day 42 after transplantation. 

  12. Esthesioneuroblastoma: A case with prolonged disease control

    Directory of Open Access Journals (Sweden)

    Andreia Coelho

    2016-10-01

    Full Text Available Esthesioneuroblastoma, a rare tumor arising from the olfactory vault, varies from being indolent to extremely aggressive. Owing to its rarity, the diagnosis, staging, and treatment of the disease are not well defined. According to a number of small observational retrospective studies and case reports, the disease’s actual treatment involves surgery, radiotherapy, and/or chemotherapy (either as a single treatment or used in combination, depending on the disease’s staging. Optimal treatment has not been standardized, particularly regarding the role of chemotherapy. We describe a case of advanced esthesioneuroblastoma with prolonged disease control, subjected to a multimodal therapy with surgery, radiotherapy, and chemotherapy, illustrating the benefits of this approach in managing a patient with esthesioneuroblastoma. Herein, we analyze the most important and controversial issues of this type of neoplasia.

  13. Neurohumoral responses during prolonged exercise in humans

    DEFF Research Database (Denmark)

    Nybo, Lars; Nielsen, Bodil; Blomstrand, Eva

    2003-01-01

    , and the metabolic precursor of serotonin, tryptophan, were evaluated in eight endurance-trained subjects during exercise randomized to be with or without hyperthermia. The core temperature stabilized at 37.9 +/- 0.1 degrees C (mean +/- SE) in the control trial, whereas it increased to 39.7 +/- 0.2 degrees C......This study examined neurohumoral alterations during prolonged exercise with and without hyperthermia. The cerebral oxygen-to-carbohydrate uptake ratio (O2/CHO = arteriovenous oxygen difference divided by arteriovenous glucose difference plus one-half lactate), the cerebral balances of dopamine...... in the hyperthermic trial, with a concomitant increase in perceived exertion (P exercise trials. Both the arterial and jugular venous dopamine levels...

  14. Neurohumoral responses during prolonged exercise in humans

    DEFF Research Database (Denmark)

    Nybo, Lars; Nielsen, Bodil; Blomstrand, Eva

    2003-01-01

    in the hyperthermic trial, with a concomitant increase in perceived exertion (P brain had a small release of tryptophan (arteriovenous difference of -1.2 +/- 0.3 micromol/l), whereas a net balance was obtained during the two exercise trials. Both the arterial and jugular venous dopamine levels...... became elevated during the hyperthermic trial, but the net release from the brain was unchanged. During exercise, the O2/CHO was similar across trials, but, during recovery from the hyperthermic trial, the ratio decreased to 3.8 +/- 0.3 (P ...This study examined neurohumoral alterations during prolonged exercise with and without hyperthermia. The cerebral oxygen-to-carbohydrate uptake ratio (O2/CHO = arteriovenous oxygen difference divided by arteriovenous glucose difference plus one-half lactate), the cerebral balances of dopamine...

  15. Endosomal generation of cAMP in GPCR signaling

    Science.gov (United States)

    Vilardaga, Jean-Pierre; Jean-Alphonse, Frederic G.; Gardella, Thomas J.

    2015-01-01

    It has been widely assumed that the production of the ubiquitous second messenger cyclic AMP, which is mediated by cell surface G protein–coupled receptors (GPCRs), and its termination take place exclusively at the plasma membrane. Recent studies reveal that diverse GPCRs do not always follow this conventional paradigm. In the new model, GPCRs mediate G-protein signaling not only from the plasma membrane but also from endosomal membranes. This model proposes that following ligand binding and activation, cell surface GPCRs internalize and redistribute into early endosomes, where trimeric G protein signaling can be maintained for an extended period of time. This Perspective discusses the molecular and cellular mechanistic subtleties as well as the physiological consequences of this unexpected process, which is considerably changing how we think about GPCR signaling and regulation and how we study drugs that target this receptor family. PMID:25271346

  16. Polynomial solutions of the Monge-Ampère equation

    Energy Technology Data Exchange (ETDEWEB)

    Aminov, Yu A [B.Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, Khar' kov (Ukraine)

    2014-11-30

    The question of the existence of polynomial solutions to the Monge-Ampère equation z{sub xx}z{sub yy}−z{sub xy}{sup 2}=f(x,y) is considered in the case when f(x,y) is a polynomial. It is proved that if f is a polynomial of the second degree, which is positive for all values of its arguments and has a positive squared part, then no polynomial solution exists. On the other hand, a solution which is not polynomial but is analytic in the whole of the x, y-plane is produced. Necessary and sufficient conditions for the existence of polynomial solutions of degree up to 4 are found and methods for the construction of such solutions are indicated. An approximation theorem is proved. Bibliography: 10 titles.

  17. Probes of the Mitochondrial cAMP-dependent Protein Kinase

    Science.gov (United States)

    Shell, Jennifer R.; Lawrence, David S.

    2013-01-01

    The development of a fluorescent assay to detect activity of the mitochondrial cAMP-dependent protein kinase (PKA) is described. A peptide-based sensor was utilized to quantify the relative amount of PKA activity present in each compartment of the mitochondria (the outer membrane, the intermembrane space, and the matrix). In the process of validating this assay, we discovered that PKA activity is regulated by the protease calpain. Upon exposure of bovine heart mitochondria to digitonin, Ca2+, and a variety of electron transport chain inhibitors, the regulatory subunits of the PKA holoenzyme (R2C2) are digested, releasing active catalytic subunits. This proteolysis is attenuated by calpain inhibitor I (ALLN). PMID:23410952

  18. Emerging Roles of AMP-Activated Protein Kinase

    DEFF Research Database (Denmark)

    Fritzen, Andreas Mæchel

    The cellular energy sensor AMP-activated protein kinase (AMPK) is activated, when the energy balance of the cell decreases. AMPK has been proposed to regulate multiple metabolic processes. However, much of the evidence for these general effects of AMPK relies on investigations in cell systems...... exercise appears to inhibit pyruvate dehydrogenase (PDH) activity by an immediate up-regulation of pyruvate dehydrogenase kinase 4 (PDK4) protein content. Consequently, this may inhibit glucose oxidation and thereby generate conditions for increased FA oxidation and glycogen resynthesis in skeletal muscle...... be of importance for prioritising energy dissipation, inhibition of lipid storage pathways and regulation of mitochondrial and metabolic proteins, but this needs further investigations. In addition, we provide evidence that AMPK is regulating autophagic signalling in skeletal muscle. Thus, in skeletal muscle AMPK...

  19. Mechanisms of Altered Control of Proliferation by Cyclic Amp/Protein Kinase A During Mammary Tumor Progression

    National Research Council Canada - National Science Library

    Imagawa, Walter

    1999-01-01

    We hypothesize that alterations in the regulation of growth by growth factors and cAMP during mammary tumor progression are related to MAP kinase signaling pathways known to be affected by cAMP and pertussis toxin (PT...

  20. Alginate-polyvinyl alcohol based interpenetrating polymer network for prolonged drug therapy, Optimization and in-vitro characterization.

    Science.gov (United States)

    Anwar, Hina; Ahmad, Mahmood; Minhas, Muhammad Usman; Rehmani, Sahrish

    2017-06-15

    A new natural and synthetic polymeric blend to form interpenetrating polymer network (IPN) hydrogels was synthesized utilizing sodium alginate and PVA as polymers by free radical polymerization employing 2-Acylamido-2-methylpropane-sulfonic acid as monomer (AMPS) and tramadol HCl as model drug through 3 2 level full factorial design to evaluate the impact of selected independent factors i.e. polymer (sodium alginate) and monomer (AMPS) contents on swelling index at 18th hour, percent drug release at 18th hour, time required for 80% drug release and drug entrapment efficiency as dependent variables. FTIR, SEM, sol-gel analysis, equilibrium swelling studies and in-vitro release kinetics were performedfor in-vitro characterization of formulated IPN hydrogels. In-vitro studies carried out at pH 1.2 and pH 7.4 revealed pH independent swelling and drug release from polymeric IPN, providing controlled drug release for an extended period of time with improved entrapment efficiency, thereby concluding that this polymeric blend may be a promising system for the prolonged drug delivery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. cAMP-binding proteins in medullary tubules from rat kidney: effect of ADH

    International Nuclear Information System (INIS)

    Gapstur, S.M.; Homma, S.; Dousa, T.P.

    1988-01-01

    Little is known of the regulatory steps in the cellular action of vasopressin (AVP) on the renal epithelium, subsequent to the cAMP generation. We studied cAMP-binding proteins in the medullary collecting tubule (MCT) and the thick ascending limb of Henle's loop (MTAL) microdissected from the rat kidney by use of photoaffinity labeling. Microdissected tubules were homogenized and photoaffinity labeled by incubation with 1 microM 32P-labeled 8-azido-adenosine 3',5'-cyclic monophosphate (N3-8-[32P]-cAMP); the incorporated 32P was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Both in MCT and MTAL preparations, the analyses showed incorporation of N3-8-[32P]cAMP into two bands (Mr = 49,000 and Mr = 55,000) that comigrated with standards of the cAMP-dependent protein kinase regulatory subunits RI and RII. In MCT, most of the 32P (80%) was incorporated into RI, whereas in MTAL the 32P incorporated into RI and RII was equivalent. When freshly dissected MCT segments were incubated with 10(-12)-10(-6) M AVP, the subsequent photoaffinity labeling of RI with N3-8-[32P]cAMP was markedly diminished in a dose-dependent manner compared with controls. Our results suggest that cAMP binds in MCT and MTAL to regulatory subunits RI and RII of cAMP-dependent protein kinase. However, in MCT the dominant type of cAMP-dependent protein kinase appears to be type I. The outlined procedure is suitable to indirectly measure the occupancy of RI by endogenous cAMP generated in MCT cells in response to physiological levels (10(-12) M) of AVP

  2. Differential regulation by AMP and ADP of AMPK complexes containing different γ subunit isoforms.

    Science.gov (United States)

    Ross, Fiona A; Jensen, Thomas E; Hardie, D Grahame

    2016-01-15

    The γ subunits of heterotrimeric AMPK complexes contain the binding sites for the regulatory adenine nucleotides AMP, ADP and ATP. We addressed whether complexes containing different γ isoforms display different responses to adenine nucleotides by generating cells stably expressing FLAG-tagged versions of the γ1, γ2 or γ3 isoform. When assayed at a physiological ATP concentration (5 mM), γ1- and γ2-containing complexes were allosterically activated almost 10-fold by AMP, with EC50 values one to two orders of magnitude lower than the ATP concentration. By contrast, γ3 complexes were barely activated by AMP under these conditions, although we did observe some activation at lower ATP concentrations. Despite this, all three complexes were activated, due to increased Thr(172) phosphorylation, when cells were incubated with mitochondrial inhibitors that increase cellular AMP. With γ1 complexes, activation and Thr(172) phosphorylation induced by the upstream kinase LKB1 [liver kinase B1; but not calmodulin-dependent kinase kinase (CaMKKβ)] in cell-free assays was markedly promoted by AMP and, to a smaller extent and less potently, by ADP. However, effects of AMP or ADP on activation and phosphorylation of the γ2 and γ3 complexes were small or insignificant. Binding of AMP or ADP protected all three γ subunit complexes against inactivation by Thr(172) dephosphorylation; with γ2 complexes, ADP had similar potency to AMP, but with γ1 and γ3 complexes, ADP was less potent than AMP. Thus, AMPK complexes containing different γ subunit isoforms respond differently to changes in AMP, ADP or ATP. These differences may tune the responses of the isoforms to fit their differing physiological roles. © 2016 Authors.

  3. cAMP Signaling Compartmentation: Adenylyl Cyclases as Anchors of Dynamic Signaling Complexes.

    Science.gov (United States)

    Johnstone, Timothy B; Agarwal, Shailesh R; Harvey, Robert D; Ostrom, Rennolds S

    2018-04-01

    It is widely accepted that cAMP signaling is compartmentalized within cells. However, our knowledge of how receptors, cAMP signaling enzymes, effectors, and other key proteins form specific signaling complexes to regulate specific cell responses is limited. The multicomponent nature of these systems and the spatiotemporal dynamics involved as proteins interact and move within a cell make cAMP responses highly complex. Adenylyl cyclases, the enzymatic source of cAMP production, are key starting points for understanding cAMP compartments and defining the functional signaling complexes. Three basic elements are required to form a signaling compartment. First, a localized signal is generated by a G protein-coupled receptor paired to one or more of the nine different transmembrane adenylyl cyclase isoforms that generate the cAMP signal in the cytosol. The diffusion of cAMP is subsequently limited by several factors, including expression of any number of phosphodiesterases (of which there are 24 genes plus spice variants). Finally, signal response elements are differentially localized to respond to cAMP produced within each locale. A-kinase-anchoring proteins, of which there are 43 different isoforms, facilitate this by targeting protein kinase A to specific substrates. Thousands of potential combinations of these three elements are possible in any given cell type, making the characterization of cAMP signaling compartments daunting. This review will focus on what is known about how cells organize cAMP signaling components as well as identify the unknowns. We make an argument for adenylyl cyclases being central to the formation and maintenance of these signaling complexes. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  4. Identification of the Components Involved in Cyclic Di-AMP Signaling in Mycoplasma pneumoniae

    Directory of Open Access Journals (Sweden)

    Cedric Blötz

    2017-07-01

    Full Text Available Bacteria often use cyclic dinucleotides as second messengers for signal transduction. While the classical molecule c-di-GMP is involved in lifestyle selection, the functions of the more recently discovered signaling nucleotide cyclic di-AMP are less defined. For many Gram-positive bacteria, c-di-AMP is essential for growth suggesting its involvement in a key cellular function. We have analyzed c-di-AMP signaling in the genome-reduced pathogenic bacterium Mycoplasma pneumoniae. Our results demonstrate that these bacteria produce c-di-AMP, and we could identify the diadenylate cyclase CdaM (MPN244. This enzyme is the founding member of a novel family of diadenylate cyclases. Of two potential c-di-AMP degrading phosphodiesterases, only PdeM (MPN549 is active in c-di-AMP degradation, whereas NrnA (MPN140 was reported to degrade short oligoribonucleotides. As observed in other bacteria, both the c-di-AMP synthesizing and the degrading enzymes are essential for M. pneumoniae suggesting control of a major homeostatic process. To obtain more insights into the nature of this process, we have identified a c-di-AMP-binding protein from M. pneumoniae, KtrC. KtrC is the cytoplasmic regulatory subunit of the low affinity potassium transporter KtrCD. It is established that binding of c-di-AMP inhibits the KtrCD activity resulting in a limitation of potassium uptake. Our results suggest that the control of potassium homeostasis is the essential function of c-di-AMP in M. pneumoniae.

  5. Positive Effect of Carbon Sources on Natural Transformation in Escherichia coli: Role of Low-Level Cyclic AMP (cAMP)-cAMP Receptor Protein in the Derepression of rpoS.

    Science.gov (United States)

    Guo, Mengyue; Wang, Huanyu; Xie, Nengbin; Xie, Zhixiong

    2015-10-01

    Natural plasmid transformation of Escherichia coli is a complex process that occurs strictly on agar plates and requires the global stress response factor σ(S). Here, we showed that additional carbon sources could significantly enhance the transformability of E. coli. Inactivation of phosphotransferase system genes (ptsH, ptsG, and crr) caused an increase in the transformation frequency, and the addition of cyclic AMP (cAMP) neutralized the promotional effect of carbon sources. This implies a negative role of cAMP in natural transformation. Further study showed that crp and cyaA mutations conferred a higher transformation frequency, suggesting that the cAMP-cAMP receptor protein (CRP) complex has an inhibitory effect on transformation. Moreover, we observed that rpoS is negatively regulated by cAMP-CRP in early log phase and that both crp and cyaA mutants show no transformation superiority when rpoS is knocked out. Therefore, it can be concluded that both the crp and cyaA mutations derepress rpoS expression in early log phase, whereby they aid in the promotion of natural transformation ability. We also showed that the accumulation of RpoS during early log phase can account for the enhanced transformation aroused by additional carbon sources. Our results thus demonstrated that the presence of additional carbon sources promotes competence development and natural transformation by reducing cAMP-CRP and, thus, derepressing rpoS expression during log phase. This finding could contribute to a better understanding of the relationship between nutrition state and competence, as well as the mechanism of natural plasmid transformation in E. coli. Escherichia coli, which is not usually considered to be naturally transformable, was found to spontaneously take up plasmid DNA on agar plates. Researching the mechanism of natural transformation is important for understanding the role of transformation in evolution, as well as in the transfer of pathogenicity and antibiotic

  6. Hot callusing for propagation of American beech by grafting

    Science.gov (United States)

    David W. Carey; Mary E. Mason; Paul Bloese; Jennifer L. Koch

    2013-01-01

    To increase grafting success rate, a hot callus grafting system was designed and implemented as part of a multiagency collaborative project to manage beech bark disease (BBD) through the establishment of regional BBD-resistant grafted seed orchards. Five years of data from over 2000 hot callus graft attempts were analyzed using a logistic regression model to determine...

  7. Graft Copolymerization of Acrylonitrile and Ethyl Methacrylate on ...

    African Journals Online (AJOL)

    Graft copolymers of Acrylonitrile and ethyl methcrylate on dextrin were prepared by the use of ceric ion initiator in aqueous medium at 290C. The molecular weight of grafted poly(ethyl methacrylate) chains were higher than for polyacrylonitrile grafts; but the latter were more frequently grafted on the backbone polymer.

  8. Revascularisation of fresh compared with demineralised bone grafts in rats

    DEFF Research Database (Denmark)

    Solheim, E; Pinholt, E M; Talsnes, O

    2001-01-01

    Revascularisation of bone grafts is influenced by both the anatomical origin and the pre-implantation processing of the graft. We investigated the revascularisation by entrapment of 141Ce (cerium)-labelled microspheres in large, fresh and demineralised syngeneic grafts of predominantly cancellous...... iliac bone grafts, p = 0.8. The results suggest that whereas fresh cancellous grafts are revascularised more completely than fresh cortical grafts, there is no difference in the revascularisation of demineralised cancellous and cortical grafts. In addition, fresh cancellous bone is revascularised more...... completely than demineralised cancellous bone, whereas there is no difference between fresh and demineralised cortical bone....

  9. Importance of B cells to development of regulatory T cells and prolongation of tissue allograft survival in recipients receiving autologous bone marrow transplantation.

    Science.gov (United States)

    Gorczynski, Reginald M; Farrokhi, Kaveh; Gorczynski, Christopher; Sadozai, Hassan; Zhu, Fang; Khatri, Ismat

    2018-01-16

    We previously showed that congenic bone marrow transplantation (BMTx) post myeloablation augmented tissue allograft survival in association with increased regulatory T (Treg) cells of both host and bone marrow donor origin. Regulatory B (Breg) cells can also modulate T-cell immunity and B cells may be implicated in the development of Treg cells. Accordingly, we explored the effect of B-cell depletion in vivo on augmented graft survival post BMTx. C57BL/6 mice received BALB/c skin allografts followed 7 days later by myeloablation using cyclophosphamide and busulphan. Mice then received T-cell-depleted bone marrow from CD45.1 congenic donors, and ongoing immunosuppression with rapamycin (to day 28 after BMTx). Control mice received cyclophosphamide and busulphan followed by rapamycin, but not congenic bone marrow. At different times post BMTx, mice received B-cell-depleting antibody treatment, and the effect on both skin graft survival, and induction of Treg cells was assessed. BMTx resulted in significantly prolonged skin graft survival versus control mice, in association with attenuated donor-specific alloreactivity relative to controls, increased splenic Treg cells and significantly diminished anti-donor IgG. In mice receiving infusion of B-depleting antibodies for 12 days from day 15 post BMTx, both graft survival and Treg cell activity were diminished, particularly for functional Treg cells of donor origin. Adoptive transfer of Breg cells from mice harvested at 15 days post BMTx prolonged survival in naive transplanted mice and increased Treg cell levels. Thus, autologous BMTx augmentation of graft survival is dependent in part upon a population of Breg cells that can modulate the function of donor-derived Treg cells. © 2018 John Wiley & Sons Ltd.

  10. Left Atrial Myxoma Following Coronary Artery Bypass Grafting with Patient Coronary Arterial Grafts: a Rarity.

    Science.gov (United States)

    Patel, Kartik; Rahul, Kumar; Tarsaria, Malkesh; Malhotra, Amber

    2017-01-01

    The development of left atrial myxoma after coronary artery bypass graft surgery is a rare entity. A 60-year-old man with previous off-pump coronary artery bypass grafting four years ago with patent coronary grafts was diagnosed with left atrial mass. The patient underwent successful resection of the same through minimally invasive right anterolateral thoracotomy. Histopathology of the atrial mass confirmed the diagnosis of atrial myxoma.

  11. Cambial Isoperoxidases Related to Graft Compatibility in Pear-Quince Graft Combinations

    OpenAIRE

    GÜLEN*, Hatice; ÇELİK, Menşure; POLAT, Mehmet; ERİŞ, Atilla

    2014-01-01

    This study was initiated to survey the graft compatibility characteristics of some selected quince clones known as "S.Ö." with regard to isoperoxidase markers. Compatible (Beurre Hardy = BH) and incompatible (Bartlett = BT) pear cultivars were grafted on quince A (QA) and 13 S.Ö. quince clones by T budding. Bark tissues were collected from the union (4, 8 and 12 weeks after grafting) and from unbudded rootstocks in addition to current-year shoots of 2 pear scions to investig...

  12. Study on preirradiation grafting of methacrylamide onto natural silk fabrics

    International Nuclear Information System (INIS)

    Xiang Zhengyu; Wan Dairong

    1997-09-01

    In order to improve the properties of natural silk fabrics, the mechanism and method of the radiation induced graft copolymerization of monomers onto natural silk fabrics were more studied. Grafting of methacrylamide onto natural silk fabrics by the preirradiation grafting method have been made. The dependencies of the grafting yield on preirradiation dose, dose rates, grafting reaction time, monomers content and moisture in sample were investigated respectively. The mechanism of the preirradiation grafting was discussed. The comparison of the preirradiation grafting method with the radiation-induced solid phase graft copolymerization was made. It is evident that the preirradiation grafting method has many advantages. It can carry out surface layer graft of monomer onto natural silk fabrics. The printing and dyeing performance was improved and so on. (5 refs., 5 figs., 1 tab.)

  13. Atrazine acts as an endocrine disrupter by inhibiting cAMP-specific phosphodiesterase-4

    Energy Technology Data Exchange (ETDEWEB)

    Kucka, Marek [Section on Cellular Signaling, Program in Developmental Neuroscience, NICHD, NIH, Bethesda, MD (United States); Pogrmic-Majkic, Kristina; Fa, Svetlana [Laboratory for Ecotoxicology, Department of Biology and Ecology, University of Novi Sad, Faculty of Sciences, 21000 Novi Sad (Serbia); Stojilkovic, Stanko S. [Section on Cellular Signaling, Program in Developmental Neuroscience, NICHD, NIH, Bethesda, MD (United States); Kovacevic, Radmila, E-mail: radmila.kovacevic@dbe.uns.ac.rs [Laboratory for Ecotoxicology, Department of Biology and Ecology, University of Novi Sad, Faculty of Sciences, 21000 Novi Sad (Serbia)

    2012-11-15

    Atrazine, one of the most commonly used herbicides worldwide, acts as an endocrine disruptor, but the mechanism of its action has not been characterized. In this study, we show that atrazine rapidly increases cAMP levels in cultured rat pituitary and testicular Leydig cells in a concentration-dependent manner, but less effectively than 3-isobutyl-1-methylxanthine, a competitive non-specific inhibitor of phosphodiesterases (PDEs). In forskolin (an activator of adenylyl cyclase)- and probenecid (an inhibitor of cyclic nucleotide transporters)-treated cells, but not in 3-isobutyl-1-methylxanthine-treated cells, atrazine further increased cAMP levels, indicating that inhibition of PDEs accounts for accumulation of cAMP. In contrast to cAMP, atrazine did not alter cGMP levels, further indicating that it inhibits cAMP-specific PDEs. Atrazine-induced changes in cAMP levels were sufficient to stimulate prolactin release in pituitary cells and androgen production in Leydig cells, indicating that it acts as an endocrine disrupter both in cells that secrete by exocytosis of prestored hormones and in cells that secrete by de novo hormone synthesis. Rolipram abolished the stimulatory effect of atrazine on cAMP release in both cell types, suggesting that it acts as an inhibitor of PDE4s, isoforms whose mRNA transcripts dominate in pituitary and Leydig cells together with mRNA for PDE8A. In contrast, immortalized lacto-somatotrophs showed low expression of these mRNA transcripts and several fold higher cAMP levels compared to normal pituitary cells, and atrazine was unable to further increase cAMP levels. These results indicate that atrazine acts as a general endocrine disrupter by inhibiting cAMP-specific PDE4s. -- Highlights: ► Atrazine stimulates cAMP accumulation in pituitary and Leydig cells. ► Atrazine also stimulates PRL and androgens secretion. ► Stimulatory effects of atrazine were abolished in cells with IBMX-inhibited PDEs. ► Atrazine specificity toward cAMP

  14. Determination of the distribution of graft yields following a radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Schipschack, K.; Wagner, H.; Sawtschenko, L.

    1976-01-01

    In the radiation-induced graft copolymerization on solid initial polymers a distribution of graft yields takes place along the cross-sections of samples. Methods for determining this distribution, which are described in the literature, are reviewed. In our own investigations boards made of ethylene-vinyl acetate copolymers and grafted with vinyl chloride were used. Distributions of the grafted component obtained by infrared analysis of microtome cuts parallel to the surface are partly rather inhomogeneous, and are interpreted as dependent on the experimental parameters. (author)

  15. Nasal Reconstrution in Revisional Rhinoplasty with Rib Graft and Olecranon Graft: Two Cases of Report

    OpenAIRE

    Pedraza Mantilla, Álvaro; Hospital Universitario San Ignacio-Pontificia Universidad Javeriana; Gélvez Rondón, Natalia; Pontificia Universidad Javeriana-Hospital Universitario San Ignacio

    2015-01-01

    Revisional rhinoplasty is a challenge for the nose surgeon. In most cases there is no septal cartilage, because that has been resected and used as a graft in previous interventions. Grafts olecranon and rib provide the properties needed to give support in the revisionales septorhinoplasty. This article presents detailed surgical technique in two males with multiple previous interventions. In one case of rib grafts were obtained in the same surgical time, in the other case, olecranon graft obt...

  16. Enrichment of autologous fat grafts with ex-vivo expanded adipose tissue-derived stem cells for graft survival

    DEFF Research Database (Denmark)

    Kølle, Stig-Frederik Trojahn; Fischer-Nielsen, Anne; Mathiasen, Anders Bruun

    2013-01-01

    Autologous fat grafting is increasingly used in reconstructive surgery. However, resorption rates ranging from 25% to 80% have been reported. Therefore, methods to increase graft viability are needed. Here, we report the results of a triple-blind, placebo-controlled trial to compare the survival ...... of fat grafts enriched with autologous adipose-derived stem cells (ASCs) versus non-enriched fat grafts....

  17. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    Directory of Open Access Journals (Sweden)

    Ying Guan

    2016-08-01

    Full Text Available Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU and polyester graft (nitinol-PET materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft.

  18. The science behind autologous fat grafting

    Directory of Open Access Journals (Sweden)

    Elisa Bellini

    2017-12-01

    Despite ongoing concerns about survival and longevity of fat grafts after implantation and unpredictability of long-term outcome, fat has been successfully used as a filler in many differ clinic situation.

  19. Free Gingival Graft versus Mucograft: Histological Evaluation

    Directory of Open Access Journals (Sweden)

    Zaklina Menceva

    2018-03-01

    CONCLUSION: The patients treated with a free gingival graft showed a larger presence of fragmented collagen tissue and fragmented elastic fibres, whereas a mature tissue was predominantly present in the surgical area where a Geistlich Mucograft was placed.

  20. AMP activated protein kinase α2 controls substrate metabolism during post-exercise recovery via regulation of pyruvate dehydrogenase kinase 4

    DEFF Research Database (Denmark)

    Fritzen, Andreas Mæchel; Lundsgaard, Annemarie; Jeppesen, Jacob

    2015-01-01

    It is well known that exercise has a major impact on substrate metabolism for many hours after exercise. However, the regulatory mechanisms increasing lipid oxidation and facilitating glycogen resynthesis in the post-exercise period are unknown. To address this, substrate oxidation was measured...... after prolonged exercise and during the following six hours post exercise in 5´AMP activated protein kinase (AMPK)α2 and α1 knock-out (KO) and wild type (WT) mice with free access to food. Substrate oxidation was similar during exercise at the same relative intensity between genotypes. During post......-exercise recovery, a lower lipid oxidation (P free-carnitine concentrations. A similar increase...

  1. Inhibition of tumor necrosis factor alpha-stimulated monocyte adhesion to human aortic endothelial cells by AMP-activated protein kinase.

    Science.gov (United States)

    Ewart, Marie-Ann; Kohlhaas, Christine F; Salt, Ian P

    2008-12-01

    Proatherosclerotic adhesion of leukocytes to the endothelium is attenuated by NO. As AMP-activated protein kinase (AMPK) regulates endothelial NO synthesis, we investigated the modulation of adhesion to cultured human aortic endothelial cells (HAECs) by AMPK. HAECs incubated with the AMPK activator, AICAR, or expressing constitutively active AMPK demonstrated reduced TNFalpha-stimulated adhesion of promonocytic U-937 cells. Rapid inhibition of TNFalpha-stimulated U-937 cell adhesion by AICAR was NO-dependent, associated with unaltered cell surface adhesion molecule expression, and reduced MCP-1 secretion by HAECs. In contrast, inhibition of TNFalpha-stimulated U-937 cell adhesion by prolonged AMPK activation was NO-independent and associated with reduced cell surface adhesion molecule expression. AMPK activation in HAECs inhibits TNFalpha-stimulated leukocyte adhesion by a rapid NO-dependent mechanism associated with reduced MCP-1 secretion and a late NO-independent mechanism whereby adhesion molecule expression, in particular E-selectin, is suppressed.

  2. Non-Anastomotic Rupture of a Woven Dacron Graft in the Descending Thoracic Aorta Treated with Endovascular Stent Grafting

    Directory of Open Access Journals (Sweden)

    Youngok Lee

    2016-12-01

    Full Text Available The intrinsic structural failure of a Dacron graft resulting from the loss of structural integrity of the graft fabric can cause late graft complications. Late non-anastomotic rupture has traditionally been treated surgically via open thoracotomy. We report a case of the successful use of thoracic endovascular repair to treat a Dacron graft rupture in the descending aorta. The rupture occurred 20 years after the graft had been placed. Two stent grafts were placed at the proximal portion of the surgical graft, covering almost its entire length.

  3. DNA nanosensor surface grafting and salt dependence

    Science.gov (United States)

    Carvalho, B. G.; Fagundes, J.; Martin, A. A.; Raniero, L.; Favero, P. P.

    2013-02-01

    In this paper we investigated the Paracoccidoides brasiliensis fungus nanosensor by simulations of simple strand DNA grafting on gold nanoparticle. In order to improve the knowledge of nanoparticle environment, the addiction of salt solution was studied at the models proposed by us. Nanoparticle and DNA are represented by economic models validated by us in this paper. In addition, the DNA grafting and salt influences are evaluated by adsorption and bond energies calculations. This theoretical evaluation gives support to experimental diagnostics techniques of diseases.

  4. Fermionic covariant prolongation structure theory for supernonlinear evolution equation

    International Nuclear Information System (INIS)

    Cheng Jipeng; Wang Shikun; Wu Ke; Zhao Weizhong

    2010-01-01

    We investigate the superprincipal bundle and its associated superbundle. The super(nonlinear)connection on the superfiber bundle is constructed. Then by means of the connection theory, we establish the fermionic covariant prolongation structure theory of the supernonlinear evolution equation. In this geometry theory, the fermionic covariant fundamental equations determining the prolongation structure are presented. As an example, the supernonlinear Schroedinger equation is analyzed in the framework of this fermionic covariant prolongation structure theory. We obtain its Lax pairs and Baecklund transformation.

  5. Intermingled cAMP, cGMP and calcium spatiotemporal dynamics in developing neuronal circuits

    Directory of Open Access Journals (Sweden)

    Stefania eAveraimo

    2014-11-01

    Full Text Available cAMP critically modulates the development of neuronal connectivity. It is involved in a wide range of cellular processes that require independent regulation. However, our understanding of how this single second messenger achieves specific modulation of the signaling pathways involved remains incomplete. The subcellular compartmentalization and temporal regulation of cAMP signals have recently been identified as important coding strategies leading to specificity. Dynamic interactions of this cyclic nucleotide with other second messenger including calcium and cGMP are critically involved in the regulation of spatiotemporal control of cAMP. Recent technical improvements of fluorescent sensors facilitate cAMP monitoring, whereas optogenetic tools permit spatial and temporal control of cAMP manipulations, all of which enabled the direct investigation of spatiotemporal characteristics of cAMP modulation in developing neurons. Focusing on neuronal polarization, neurotransmitter specification, axon guidance, and refinement of neuronal connectivity, we summarize herein the recent advances in understanding the features of cAMP signals and their dynamic interactions with calcium and cGMP involved in shaping the nervous system.

  6. Sustained exposure to catecholamines affects cAMP/PKA compartmentalised signalling in adult rat ventricular myocytes.

    Science.gov (United States)

    Fields, Laura A; Koschinski, Andreas; Zaccolo, Manuela

    2016-07-01

    In the heart compartmentalisation of cAMP/protein kinase A (PKA) signalling is necessary to achieve a specific functional outcome in response to different hormonal stimuli. Chronic exposure to catecholamines is known to be detrimental to the heart and disrupted compartmentalisation of cAMP signalling has been associated to heart disease. However, in most cases it remains unclear whether altered local cAMP signalling is an adaptive response, a consequence of the disease or whether it contributes to the pathogenetic process. We have previously demonstrated that isoforms of PKA expressed in cardiac myocytes, PKA-I and PKA-II, localise to different subcellular compartments and are selectively activated by spatially confined pools of cAMP, resulting in phosphorylation of distinct downstream targets. Here we investigate cAMP signalling in an in vitro model of hypertrophy in primary adult rat ventricular myocytes. By using a real time imaging approach and targeted reporters we find that that sustained exposure to catecholamines can directly affect cAMP/PKA compartmentalisation. This appears to involve a complex mechanism including both changes in the subcellular localisation of individual phosphodiesterase (PDE) isoforms as well as the relocalisation of PKA isoforms. As a result, the preferential coupling of PKA subsets with different PDEs is altered resulting in a significant difference in the level of cAMP the kinase is exposed to, with potential impact on phosphorylation of downstream targets. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Additive effects in radiation grafting and curing

    International Nuclear Information System (INIS)

    Viengkhou, V.; Ng, L.

    1996-01-01

    Full text: Detailed studies on the accelerative effect of novel additives in radiation grafting and curing using acrylated monomer/oligomer systems have been performed in the presence of ionising radiation and UV as sources. Methyl methacrylate (MMA) is used as typical monomer for these grafting studies in the presence of the additives with model backbone polymers, cellulose and propropylene. Additives which have been found to accelerate these grafting processes are: mineral acid, occlusion compounds like urea, thermal initiators and photoinitiators as well as multifunctional monomers such as multifunctional acrylates. The results from irradiation with gamma rays have also been compared with irradiation from a 90W UV lamp. The role of the above additives in accelerating the analogous process of radiation curing has been investigated. Acrylated urethanes, epoxies and polyesters are used as oligomers together with acrylated monomers in this work with uv lamps of 300 watts/inch as radiation source. In the UV curing process bonding between film and substrate is usually due to physical forces. In the present work the presence of additives are shown to influence the occurrence of concurrent grafting during cure thus affecting the nature of the bonding of the cured film. The conditions under which concurrent grafting with UV can occur will be examined. A mechanism for accelerative effect of these additives in both grafting and curing processes has been proposed involving radiation effects and partitioning phenomena

  8. Polypeptide Grafted Hyaluronan: Synthesis and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun [ORNL; Messman, Jamie M [ORNL; Mays, Jimmy [ORNL; Baskaran, Durairaj [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Poly(L-leucine) grafted hyaluronan (HA-g-PLeu) has been synthesized via a Michael addition reaction between primary amine terminated poly(L-leucine) and acrylate-functionalized HA (TBAHA-acrylate). The precursor hyaluronan was first functionalized with acrylate groups by reaction with acryloyl chloride in the presence of triethylamine in N,N-dimethylformamide. 1H NMR analysis of the resulting product indicated that an increase in the concentration of acryloylchoride with respect to hydroxyl groups on HA has only a moderate effect on functionalization efficiency, f. A precise control of stoichiometry was not achieved, which could be attributed to partial solubility of intermolecular aggregates and the hygroscopic nature of HA. Michael addition at high [PLeu- NH2]/[acrylate]TBAHA ratios gave a molar grafting ratio of only 0.20 with respect to the repeat unit of HA, indicating grafting limitation due to insolubility of the grafted HA-g-PLeu. Soluble HA-g-PLeu graft copolymers were obtained for low grafting ratios (<0.039) with <8.6% by mass of PLeu and were characterized thoroughly using light scattering, 1H NMR, FT-IR, and AFM techniques. Light scattering experiments showed a strong hydrophobic interaction between PLeu chains, resulting in aggregates with segregated nongrafted HA segments. This yields local networks of aggregates, as demonstrated by atomic force microscopy. Circular dichroism spectroscopy showed a -sheet conformation for aggregates of poly(L-leucine).

  9. New insight into the binding modes of TNP-AMP to human liver fructose-1,6-bisphosphatase

    Science.gov (United States)

    Han, Xinya; Huang, Yunyuan; Zhang, Rui; Xiao, San; Zhu, Shuaihuan; Qin, Nian; Hong, Zongqin; Wei, Lin; Feng, Jiangtao; Ren, Yanliang; Feng, Lingling; Wan, Jian

    2016-08-01

    Human liver fructose-1,6-bisphosphatase (FBPase) contains two binding sites, a substrate fructose-1,6-bisphosphate (FBP) active site and an adenosine monophosphate (AMP) allosteric site. The FBP active site works by stabilizing the FBPase, and the allosteric site impairs the activity of FBPase through its binding of a nonsubstrate molecule. The fluorescent AMP analogue, 2‧,3‧-O-(2,4,6-trinitrophenyl)adenosine 5‧-monophosphate (TNP-AMP) has been used as a fluorescent probe as it is able to competitively inhibit AMP binding to the AMP allosteric site and, therefore, could be used for exploring the binding modes of inhibitors targeted on the allosteric site. In this study, we have re-examined the binding modes of TNP-AMP to FBPase. However, our present enzyme kinetic assays show that AMP and FBP both can reduce the fluorescence from the bound TNP-AMP through competition for FBPase, suggesting that TNP-AMP binds not only to the AMP allosteric site but also to the FBP active site. Mutagenesis assays of K274L (located in the FBP active site) show that the residue K274 is very important for TNP-AMP to bind to the active site of FBPase. The results further prove that TNP-AMP is able to bind individually to the both sites. Our present study provides a new insight into the binding mechanism of TNP-AMP to the FBPase. The TNP-AMP fluorescent probe can be used to exam the binding site of an inhibitor (the active site or the allosteric site) using FBPase saturated by AMP and FBP, respectively, or the K247L mutant FBPase.

  10. The cyclic AMP cascade is altered in the fragile X nervous system.

    Directory of Open Access Journals (Sweden)

    Daniel J Kelley

    2007-09-01

    Full Text Available Fragile X syndrome (FX, the most common heritable cause of mental retardation and autism, is a developmental disorder characterized by physical, cognitive, and behavioral deficits. FX results from a trinucleotide expansion mutation in the fmr1 gene that reduces levels of fragile X mental retardation protein (FMRP. Although research efforts have focused on FMRP's impact on mGluR signaling, how the loss of FMRP leads to the individual symptoms of FX is not known. Previous studies on human FX blood cells revealed alterations in the cyclic adenosine 3', 5'-monophosphate (cAMP cascade. We tested the hypothesis that cAMP signaling is altered in the FX nervous system using three different model systems. Induced levels of cAMP in platelets and in brains of fmr1 knockout mice are substantially reduced. Cyclic AMP induction is also significantly reduced in human FX neural cells. Furthermore, cAMP production is decreased in the heads of FX Drosophila and this defect can be rescued by reintroduction of the dfmr gene. Our results indicate that a robust defect in cAMP production in FX is conserved across species and suggest that cAMP metabolism may serve as a useful biomarker in the human disease population. Reduced cAMP induction has implications for the underlying causes of FX and autism spectrum disorders. Pharmacological agents known to modulate the cAMP cascade may be therapeutic in FX patients and can be tested in these models, thus supplementing current efforts centered on mGluR signaling.

  11. Detection of Amp C genes encoding for beta-lactamases in Escherichia coli and Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    M Shanthi

    2012-01-01

    Full Text Available Purpose : Amp C beta-lactamase are Ambler class C enzymes that confer resistance to extended spectrum cephalosporins and are not inhibited by beta-lactamase inhibitors. Their detection is crucial, since the phenotypic tests are not standardised leading to ambiguity in interpretation of results. This study was done to detect the types of Amp C prevalent in Escherichia coli and Klebsiella pneumoniae by multiplex polymerase chain reaction (PCR. Materials and Methods : Seventy-seven consecutive cefoxitin resistant clinical isolates of E. coli (n = 25 and K. pneumoniae (n = 52 were included in the study. Antibiotic susceptibility testing to various classes of antibiotics was performed by disc diffusion using Clinical Laboratory Standards Institute (CLSI guidelines. Minimum inhibitory concentration (MIC to cefoxitin, imipenem and meropenem were determined by broth microdilution method. Isolates were screened for production of Extended Spectrum Beta-Lactamase (ESBL. Multiplex PCR was performed for the detection of Amp C genes after phenotypic testing (Hodge test and inhibitor based test. Results : Cefoxitin Hodge test was positive in 40 isolates which included 20 E. coli and 20 K. pneumoniae. There was zone enhancement with boronic acid in 55 isolates, of which 36 were K. pneumoniae and 19 were E. coli. Multiplex PCR detected Amp C in 11/25 E. coli and 12/52 K. pneumoniae isolates. The Amp C genes detected were CIT (Amp C origin - Citrobacter freundii, DHA (Dhahran Hospital, Saudi Arabia, ACC (Ambler class C, EBC (Amp C origin - Enterobacter cloacae groups. ESBL was co-produced in 54 isolates. Conclusions : Amp C was detected in 29.87% of the study isolates. Majority of them co-produced ESBL. The most common Amp C was the CIT family. Screen tests for cefoxitin resistance may be falsely positive due to production of carbapenamases.

  12. Isotopic scintigraphy in kidney grafting

    International Nuclear Information System (INIS)

    Renfro, Richard.

    1976-01-01

    Isotopic explorations of kidney transplants were performed on sixty-six patients. Three scintigraphic techniques were used: labelled ferrous ascorbate scintigraphy, sequential 99m technetium DTPA scintigraphy and the 131 I hippuran nephrogram. The aim of this study is to analyse the results obtained under different pathological circumstances affecting the transplant, to discuss the advantages of the techniques and to propose a working procedure. The most reliable and accurate technique is the 131 I hippuran nephrogram combined with sequential 99mTc DTPA, by which renal vascularisation may be judged labelled ferrous ascorbate on the other hand is too insensitive. Although the information supplied is mostly contained in the scintigraphic images, the nephrographic curves and the blood radioactivity decay time and rad V/rad R ratio measurements are very helpful in the early diagnosis and differential diagnosis of complications affecting the transplant. The proper use of isotopic scintigraphy in kidney grafting should provide optimum conditions for better survival of the transplant at minimum risk to the patient [fr

  13. Role of graft oversizing in the fixation strength of barbed endovascular grafts.

    Science.gov (United States)

    Kratzberg, Jarin A; Golzarian, Jafar; Raghavan, Madhavan L

    2009-06-01

    The role of endovascular graft oversizing on risk of distal graft migration following endovascular aneurysm repair for abdominal aortic aneurysm is poorly understood. A controlled in vitro investigation of the role of oversizing in graft-aorta attachment strength for endovascular grafts (EVGs) with barbs was performed. Barbed stent grafts (N = 20) with controlled graft oversizing varying from 4-45% were fabricated while maintaining other design variables unchanged. A flow loop with physiological flow characteristics and a biosynthetic aortic aneurysm phantom (synthetic aneurysm model with a bovine aortic neck) were developed. The stent grafts were deployed into the aortic neck of the bio-synthetic aortic aneurysm phantom under realistic flow conditions. Computed tomography imaging of the graft-aorta complex was used to document attachment characteristics such as graft apposition, number of barbs penetrated, and penetration depth and angle. The strength of graft attachment to the aortic neck was assessed using mechanical pullout testing. Stent grafts were categorized into four groups based on oversizing: 4-10%; 11-20%; 21-30%; and greater than 30% oversizing. Pullout force, a measure of post-deployment fixation strength was not different between 4-10% (6.23 +/- 1.90 N), 11-20% (6.25 +/- 1.84 N) and 20-30% (5.85 +/- 1.89 N) groups, but significantly lower for the group with greater than 30% oversizing (3.67 +/- 1.41 N). Increasing oversizing caused a proportional decrease in the number of barbs penetrating the aortic wall (correlation = -0.83). Of the 14 barbs available in the stent graft, 89% of the barbs (12.5 of 14 on average) penetrated the aortic wall in the 4-10% oversizing group while only 38% (5.25 of 14) did for the greater than 30% group (P barb penetration were found to be positively correlated to pullout force. Greater than 30% graft oversizing affects both barb penetration and graft apposition adversely resulting in a low pullout force in this in vitro

  14. GPCR desensitization: Acute and prolonged phases.

    Science.gov (United States)

    Rajagopal, Sudarshan; Shenoy, Sudha K

    2018-01-01

    G protein-coupled receptors (GPCRs) transduce a wide array of extracellular signals and regulate virtually every aspect of physiology. While GPCR signaling is essential, overstimulation can be deleterious, resulting in cellular toxicity or uncontrolled cellular growth. Accordingly, nature has developed a number of mechanisms for limiting GPCR signaling, which are broadly referred to as desensitization, and refer to a decrease in response to repeated or continuous stimulation. Short-term desensitization occurs over minutes, and is primarily associated with β-arrestins preventing G protein interaction with a GPCR. Longer-term desensitization, referred to as downregulation, occurs over hours to days, and involves receptor internalization into vesicles, degradation in lysosomes and decreased receptor mRNA levels through unclear mechanisms. Phosphorylation of the receptor by GPCR kinases (GRKs) and the recruitment of β-arrestins is critical to both these short- and long-term desensitization mechanisms. In addition to phosphorylation, both the GPCR and β-arrestins are modified post-translationally in several ways, including by ubiquitination. For many GPCRs, receptor ubiquitination promotes degradation of agonist-activated receptors in the lysosomes. Other proteins also play important roles in desensitization, including phosphodiesterases, RGS family proteins and A-kinase-anchoring proteins. Together, this intricate network of kinases, ubiquitin ligases, and adaptor proteins orchestrate the acute and prolonged desensitization of GPCRs. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Prolonged cholestasis and ductopenia associated with tenoxicam.

    Science.gov (United States)

    Trak-Smayra, Viviane; Cazals-Hatem, Dominique; Asselah, Tarik; Duchatelle, Veronique; Degott, Claude

    2003-07-01

    Cholestatic liver diseases leading to progressive destruction of intra-hepatic bile ducts and ductopenia encompass multiple etiologies. Pathophysiology and natural history of drug-induced cholangiopathies remain unclear. We report a case of prolonged ductopenia attributed to Tenoxicam (Tilcotil o--a non-steroidal anti-inflammatory drug of the oxicam family) ingested at therapeutic dose. A 36 year-old male patient was admitted for jaundice and Lyell syndrome starting 1 week after the ingestion of Tenoxicam. Liver biopsy showed cholestasis, non-suppurative cholangitis and polymorphous inflammatory infiltrate of the portal tracts (round cells, macrophages an eosinophils). Treatment with ursodesoxycholic acid and cholestyramine was instituted and the patient was asymptomatic 1 year after. Three years later mild biological cholestasis persisted and ductopenia was evidenced on liver biopsy. In this report we found that: (1) The toxicity of tenoxicam was probably mediated by an immunoallergic mechanism (Lyell syndrome and eosinophils on histology); (2) ductopenia was secondary to inflammatory cholangitis. Factors responsible for this chronic evolution are still unknown (genetic predisposition, vascular factors, etc.); and (3) the presence of ductopenia contrasted with the "clinical recovery" of the disease suggesting accessory bile drainage by cholangioles or partial reconstruction of the biliary tree.

  16. Gluteal Compartment Syndrome After Prolonged Immobilisation

    Directory of Open Access Journals (Sweden)

    H.L. Liu

    2009-04-01

    Full Text Available Muscles in the gluteal region are confined by distinct fascial attachments which can potentially result in compartment syndrome. A 74-year-old chronic drinker was admitted to the medical ward after being found drunk on the street. He noticed acute painful swelling of the right side of his buttock the following morning and recalled a slip and fall prior to his blackout. The whole right half of the buttock was tense with erythematous overlying skin. Examination revealed sciatic nerve palsy and myoglobinuria. Emergency fasciotomy and debridement were performed. Intra-operative pressure measurement confirmed a grossly elevated intra-compartmental pressure. Gluteal compartment syndrome is an extremely rare condition and has only been scantily documented previously in case reports. Early diagnosis is crucial but delay recognition is common from lack of knowledge of the condition and readily results in permanent sciatic nerve injury and acute renal shutdown from myoglobinuria. Awareness of the condition, early diagnosis and prompt exploration provide the only chance of avoiding these devastating consequences. Acute swelling diffusely affecting the whole or one side of the buttock, a history of trauma and prolonged local pressure impingement associated with pain out of proportion to the clinical signs should raise a suspicion of this rare condition.

  17. [A case of prolonged paroxysmal sympathetic hyperactivity].

    Science.gov (United States)

    Yamamoto, Akiko; Ide, Shuhei; Iwasaki, Yuji; Kaga, Makiko; Arima, Masataka

    2016-03-01

    We report the case of a 4-year-old girl who presented with paroxysmal sympathetic hyperactivity (PSH), after developing severe hypoxic-ischemic-encephalopathy because of cardiopulmonary arrest. She showed dramatic paroxysmal sympathetic activity with dystonia. She was treated with wide variety of medications against PSH, which were found to be effective in previous studies. Among them, morphine, bromocriptine, propranolol, and clonidine were effective in reducing the frequency of her attacks while gabapentin, baclofen, dantrolene, and benzodiazepine were ineffective. Though the paroxysms decreased markedly after the treatment, they could not be completely controlled beyond 500 days. Following the treatment, levels of plasma catecholamines and their urinary metabolites decreased to normal during inter- paroxysms. However, once a paroxysm had recurred, these levels were again very high. This case study is considered significant for two rea- sons. One is that PSH among children have been rarely reported, and the other is that this case of prolonged PSH delineated the transition of plasma catecholamines during the treatment. The excitatory: inhibitory ratio (EIR) model proposed by Baguley was considered while dis- cussing drug sensitivity in this case. Accumulation of similar case studies will help establish more effective treatment strategies and elucidate the pathophysiology of PSH.

  18. STRESS PROLONGS WOUND HEALING POST CESAREAN SECTION

    Directory of Open Access Journals (Sweden)

    Ah. Yusuf

    2017-07-01

    Full Text Available Introduction: Decision for cesarean section may lead to the stress for women in delivery. Stress response requires longer recovery time in post cesarean section patients. Most of patients who experience stress before and after surgical is associated with wound healing delay. When this condition continues, the wound will have a higher risk of infection. The objective of this study was to analyze correlation between stress and wound healing phase in post cesarean section patients. Method: A cross sectional design was used in this study. The population were women with cesarean section, both elective or emergency, in Delivery Room I RSU Dr. Soetomo Surabaya. Samples were recruited by using purposive sampling, with 28 samples who met to the inclusion criterias. The observed variables were stress and wound healing phase in post cesarean section patient. Stress data were collected by interview and wound healing measurement done by observation on the 3rd day post cesarean section. Result: The result showed that women with stress experience wound healing delay. The characteristic of wound healing delay was prolonged on inflammation phase, nevertheless there was presence of granulation tissue. Spearman’s rho correlation showed that correlation value r=0.675 with p=0.000. Discussion: It can be concluded that there was strong significant correlation between stress and wound healing phase in post cesarean section patients. It is important to give this information to the patients with cesarean section in order to prevent stress and delay in wound healing phase.

  19. Cyclic AMP regulates the biosynthesis of cellobiohydrolase in Cellulomonas flavigena growing in sugar cane bagasse.

    Science.gov (United States)

    Herrera-Herrera, Jesús Antonio; Pérez-Avalos, Odilia; Salgado, Luis M; Ponce-Noyola, Teresa

    2009-10-01

    Cellulomonas flavigena produces a battery of cellulase components that act concertedly to degrade cellulose. The addition of cAMP to repressed C. flavigena cultures released catabolic repression, while addition of cAMP to induced C. flavigena cultures led to a cellobiohydrolase hyperproduction. Exogenous cAMP showed positive regulation on cellobiohydrolase production in C. flavigena grown on sugar cane bagasse. A C. flavigena cellobiohydrolase gene was cloned (named celA), which coded for a 71- kDa enzyme. Upstream, a repressor celR1, identified as a 38 kDa protein, was monitored by use of polyclonal antibodies.

  20. Reflection principle for classical solutions of the homogeneous real Monge–Ampère equation

    Directory of Open Access Journals (Sweden)

    Mika Koskenoja

    2015-12-01

    Full Text Available We consider reflection principle for classical solutions of the homogeneous real Monge–Ampère equation. We show that both the odd and the even reflected functions satisfy the Monge–Ampère equation if the second-order partial derivatives have continuous limits on the reflection boundary. In addition to sufficient conditions, we give some necessary conditions. Before stating the main results, we present elementary formulas for the reflected functions and study their differentiability properties across the reflection boundary. As an important special case, we finally consider extension of polynomials satisfying the homogeneous Monge–Ampère equation.

  1. A high-speed CMOS current op amp for very low supply voltage operation

    DEFF Research Database (Denmark)

    Bruun, Erik

    1994-01-01

    A CMOS implementation of a high-gain current mode operational amplifier (op amp) with a single-ended input and a differential output is described. This configuration is the current mode counterpart of the traditional voltage mode op amp. In order to exploit the inherent potential for high speed......, low voltage operation normally associated with current mode analog signal processing, the op amp has been designed to operate off a supply voltage of 1.5 V, and the signal path has been confined to N-channel transistors. With this design, a gain of 94 dB and a gain-bandwidth product of 65 MHz has been...

  2. Bipolar power sources for the correction magnets of AmPS

    International Nuclear Information System (INIS)

    Es, J.T. van; Luigjes, G.; Trigt, J.H. van.

    1992-01-01

    AmPS consists of many correction magnets which must provide the currents. These currents serve continuously between -3 Amp and +3 Amp. The adjusted current must be stable inside 0,1%. The copper resistance of magnet coils and their wires are ≤ 8 ohm and the self induction is 200 mH. An extended market research on power supplies has enabled the authors to decide to develop it themselves. This development has led to a module system with Bitbus control. (authors). 14 figs., 4 tabs

  3. TNP-AMP Binding to the Sarcoplasmic Reticulum Ca2+-ATPase Studied by Infrared Spectroscopy

    OpenAIRE

    Liu, Man; Barth, Andreas

    2003-01-01

    Infrared spectroscopy was used to monitor the conformational change of 2′,3′-O-(2,4,6-trinitrophenyl)adenosine 5′-monophosphate (TNP-AMP) binding to the sarcoplasmic reticulum Ca2+-ATPase. TNP-AMP binding was observed in a competition experiment: TNP-AMP is initially bound to the ATPase but is then replaced by β,γ-iminoadenosine 5′-triphosphate (AMPPNP) after AMPPNP release from P3-1-(2-nitrophenyl)ethyl AMPPNP (caged AMPPNP). The resulting infrared difference spectra are compared to those of...

  4. Analysis of Advanced Modular Power Systems (AMPS) for Deep Space Exploration

    Science.gov (United States)

    Oeftering, Richard; Soeder, James F.; Beach, Ray

    2014-01-01

    The Advanced Modular Power Systems (AMPS) project is developing a modular approach to spacecraft power systems for exploration beyond Earth orbit. AMPS is intended to meet the need of reducing the cost of design development, test and integration and also reducing the operational logistics cost of supporting exploration missions. AMPS seeks to establish modular power building blocks with standardized electrical, mechanical, thermal and data interfaces that can be applied across multiple exploration vehicles. The presentation discusses the results of a cost analysis that compares the cost of the modular approach against a traditional non-modular approach.

  5. Structural analyses of a constitutively active mutant of exchange protein directly activated by cAMP.

    Science.gov (United States)

    White, Mark A; Li, Sheng; Tsalkova, Tamara; Mei, Fang C; Liu, Tong; Woods, Virgil L; Cheng, Xiaodong

    2012-01-01

    Exchange proteins directly activated by cAMP (EPACs) are important allosteric regulators of cAMP-mediated signal transduction pathways. To understand the molecular mechanism of EPAC activation, we have combined site-directed mutagenesis, X-ray crystallography, and peptide amide hydrogen/deuterium exchange mass spectrometry (DXMS) to probe the structural and conformational dynamics of EPAC2-F435G, a constitutively active EPAC2 mutant. Our study demonstrates that conformational dynamics plays a critical role in cAMP-induced EPAC activation. A glycine mutation at 435 position shifts the equilibrium of conformational dynamics towards the extended active conformation.

  6. Structural analyses of a constitutively active mutant of exchange protein directly activated by cAMP.

    Directory of Open Access Journals (Sweden)

    Mark A White

    Full Text Available Exchange proteins directly activated by cAMP (EPACs are important allosteric regulators of cAMP-mediated signal transduction pathways. To understand the molecular mechanism of EPAC activation, we have combined site-directed mutagenesis, X-ray crystallography, and peptide amide hydrogen/deuterium exchange mass spectrometry (DXMS to probe the structural and conformational dynamics of EPAC2-F435G, a constitutively active EPAC2 mutant. Our study demonstrates that conformational dynamics plays a critical role in cAMP-induced EPAC activation. A glycine mutation at 435 position shifts the equilibrium of conformational dynamics towards the extended active conformation.

  7. Physical properties of agave cellulose graft polymethyl methacrylate

    International Nuclear Information System (INIS)

    Rosli, Noor Afizah; Ahmad, Ishak; Abdullah, Ibrahim; Anuar, Farah Hannan

    2013-01-01

    The grafting polymerization of methyl methacrylate and Agave cellulose was prepared and their structural analysis and morphology were investigated. The grafting reaction was carried out in an aqueous medium using ceric ammonium nitrate as an initiator. The structural analysis of the graft copolymers was carried out by Fourier transform infrared and X-ray diffraction. The graft copolymers were also characterized by field emission scanning electron microscopy (FESEM). An additional peak at 1732 cm −1 which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted Agave cellulose, respectively. Another evidence of grafting showed in the FESEM observation, where the surface of the grafted cellulose was found to be roughed than the raw one

  8. Physical properties of agave cellulose graft polymethyl methacrylate

    Science.gov (United States)

    Rosli, Noor Afizah; Ahmad, Ishak; Abdullah, Ibrahim; Anuar, Farah Hannan

    2013-11-01

    The grafting polymerization of methyl methacrylate and Agave cellulose was prepared and their structural analysis and morphology were investigated. The grafting reaction was carried out in an aqueous medium using ceric ammonium nitrate as an initiator. The structural analysis of the graft copolymers was carried out by Fourier transform infrared and X-ray diffraction. The graft copolymers were also characterized by field emission scanning electron microscopy (FESEM). An additional peak at 1732 cm-1 which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted Agave cellulose, respectively. Another evidence of grafting showed in the FESEM observation, where the surface of the grafted cellulose was found to be roughed than the raw one.

  9. DmAMP1, an antifungal plant defensin from dahlia (Dahlia merckii), interacts with sphingolipids from Saccharomyces cerevisiae.

    Science.gov (United States)

    Thevissen, Karin; François, Isabelle E J A; Takemoto, Jon Y; Ferket, Kathelijne K A; Meert, Els M K; Cammue, Bruno P A

    2003-09-12

    DmAMP1, an antifungal plant defensin from Dahlia merckii, was shown previously to require the presence of sphingolipids for fungicidal action against Saccharomyces cerevisiae. Sphingolipids may stabilize glycosylphosphatidylinositol (GPI)-anchored proteins, which interact with DmAMP1, or they may directly serve as DmAMP1 binding sites. In the present study, we demonstrate that S. cerevisiae disruptants in GPI-anchored proteins showed small or no increased resistance towards DmAMP1 indicating no involvement of these proteins in DmAMP1 action. Further, studies using an enzyme-linked immunosorbent assay (ELISA)-based binding assay revealed that DmAMP1 interacts directly with sphingolipids isolated from S. cerevisiae and that this interaction is enhanced in the presence of equimolar concentrations of ergosterol. Therefore, DmAMP1 antifungal action involving membrane interaction with sphingolipids and ergosterol is proposed.

  10. [Experimental study of allogenic tendon with sheath grafting in chicken].

    Science.gov (United States)

    Zhang, Y L; Wang, S L; Gao, X S

    2001-03-01

    To investigate availability of deep freeze stored allogenic tendon with sheath grafting in repairing the tendon and sheath defect in the II area of flexor digitorum tendon. Sixty chickens with tendon and sheath defect were divided into 2 groups randomly, group A was treated with allogenic grafting and group B was treated with autogenic grafting, these two groups were divided into two subgroups respectively, they were, group A1 allogenic tendon with whole sheath grafting, group A2 allogenic tendon with partial sheath grafting, group B1 autogenic tendon with whole sheath grafting and group B2 autogenic tendon with whole sheath grafting. All the allogenic grafts were treated by deep freeze. Histomorphological study, histoimmunological study and slipping function of the grafts were measured after operation. In group A1 and B1, the local reaction was sever, the nutrition of tendon graft was barricaded by the whole sheath resulting in adhesion, degeneration and necrosis. In group A2 and B2, the tendon graft healed well and little adhesion existed between tendon and sheath. The results showed that there were significant differences between tendon grafting with whole sheath and tendon grafting with partial sheath. Deep freeze store can reduce the immunogenicity of allogenic tendon with sheath. Allogenic tendon with partial sheath grafting can be used as a new biological material for repairing the tendon and sheath defect.

  11. Structural implications of fenestrated stent graft misalignment.

    Science.gov (United States)

    Crawford, S A; Itkina, M; Doyle, M G; Tse, L W; Amon, C H; Roche-Nagle, G

    2018-04-01

    Endovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model. A custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured. The Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak. Both the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment. Copyright © 2016 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  12. Complications in skin grafts when continuing antithrombotic therapy prior to cutaneous surgery requiring skin grafting

    DEFF Research Database (Denmark)

    Jarjis, Reem Dina; Jørgensen, Lone; Finnerup, Kenneth

    2015-01-01

    in terms of hemostasis by the surgeon and good pressure dressings. Care should be taken when operating on anticoagulated patients undergoing cutaneous surgery requiring skin grafting. However, graft failure is rare and, given the risk of thrombotic events, the reviewed studies recommend continuing all......Abstract The risk of postoperative bleeding and wound healing complications in skin grafts among anticoagulated patients undergoing cutaneous surgery has not been firmly established. The objective was to examine the literature and assess the risk of postoperative bleeding or wound healing...... complications in skin grafts among anticoagulated patients, compared with patients who discontinue or patients who are not receiving antithrombotic therapy prior to cutaneous surgery requiring skin grafting. A systematic review examining the effect of antithrombotic therapy on cutaneous surgery was performed...

  13. Static Load Balancing Algorithms In Cloud Computing Challenges amp Solutions

    Directory of Open Access Journals (Sweden)

    Nadeem Shah

    2015-08-01

    Full Text Available Abstract Cloud computing provides on-demand hosted computing resources and services over the Internet on a pay-per-use basis. It is currently becoming the favored method of communication and computation over scalable networks due to numerous attractive attributes such as high availability scalability fault tolerance simplicity of management and low cost of ownership. Due to the huge demand of cloud computing efficient load balancing becomes critical to ensure that computational tasks are evenly distributed across servers to prevent bottlenecks. The aim of this review paper is to understand the current challenges in cloud computing primarily in cloud load balancing using static algorithms and finding gaps to bridge for more efficient static cloud load balancing in the future. We believe the ideas suggested as new solution will allow researchers to redesign better algorithms for better functionalities and improved user experiences in simple cloud systems. This could assist small businesses that cannot afford infrastructure that supports complex amp dynamic load balancing algorithms.

  14. Hypoxia inhibits colonic ion transport via activation of AMP kinase.

    LENUS (Irish Health Repository)

    Collins, Danielle

    2012-02-01

    BACKGROUND AND AIMS: Mucosal hypoxia is a common endpoint for many pathological processes including ischemic colitis, colonic obstruction and anastomotic failure. Previous studies suggest that hypoxia modulates colonic mucosal function through inhibition of chloride secretion. However, the molecular mechanisms underlying this observation are poorly understood. AMP-activated protein kinase (AMPK) is a metabolic energy regulator found in a wide variety of cells and has been linked to cystic fibrosis transmembrane conductance regulator (CFTR) mediated chloride secretion in several different tissues. We hypothesized that AMPK mediates many of the acute effects of hypoxia on human and rat colonic electrolyte transport. METHODS: The fluorescent chloride indicator dye N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide was used to measure changes in intracellular chloride concentrations in isolated single rat colonic crypts. Ussing chamber experiments in human colonic mucosa were conducted to evaluate net epithelial ion transport. RESULTS: This study demonstrates that acute hypoxia inhibits electrogenic chloride secretion via AMPK mediated inhibition of CFTR. Pre-treatment of tissues with the AMPK inhibitor 6-[4-(2-piperidin-1-yl-ethoxy)-phenyl)]-3-pyridin-4-yl-pyyrazolo [1,5-a] pyrimidine (compound C) in part reversed the effects of acute hypoxia on chloride secretion. CONCLUSION: We therefore suggest that AMPK is a key component of the adaptive cellular response to mucosal hypoxia in the colon. Furthermore, AMPK may represent a potential therapeutic target in diseased states or in prevention of ischemic intestinal injury.

  15. Leg fluid accumulation during prolonged sitting.

    Science.gov (United States)

    Vena, Daniel; Rubianto, Jonathan; Popovic, Milos; Yadollahi, Azadeh

    2016-08-01

    The accumulation of fluid in the legs due to sedentariness can be a health risk in extreme cases. Negative health impacts associated with leg fluid accumulation include leg edema and risk of blood clots. Furthermore, fluid accumulating in the legs is accompanied by fluid shift into the upper body which is also associated with health risks such as: increased blood pressure when lying down, respiratory problems in people with heart failure, and increased sleep apnea. Understanding the pattern by which fluid accumulates in the legs can aid in the development of devices for reducing leg fluid accumulation. The purpose of this study was to characterize the time course of fluid accumulation over a two-and-half-hour seated period. Non-obese participants with sleep apnea and no other co-morbidities were included in the sample as part of a larger study. Leg fluid was measured continuously using a method of bioelectrical impedance. Participants were first asked to lie supine for 30 minutes as a washout, and then sat with their legs still for two and a half hours. The main finding of this study is that the pattern of leg fluid accumulation differed in the first 45 minutes compared to the latter 105 minutes. In the first 45 minutes, fluid accumulated according to first order exponential function. In the latter period, fluid accumulated according to a linear function. The initial exponential accumulation is likely due to the large increase in capillary pressure caused by rapid blood flow into the legs due to gravity, leading to substantial filtration of blood plasma into the tissue spaces. The latter linear portion likely represents continued slow filtration of fluid out of the vasculature and into the tissue spaces. This is the first study to show that fluid accumulation in the legs is a combination of an exponential and linear functions. The linear increase identifies that there is no foreseeable point in which leg fluid stops accumulating while sitting for prolonged periods.

  16. Encephalitis with Prolonged but Reversible Splenial Lesion

    Directory of Open Access Journals (Sweden)

    Alena Meleková

    2015-12-01

    Full Text Available Introduction: The splenium of the corpus callosum has a specific structure of blood supply with a tendency towards blood-brain barrier breakdown, intramyelinic edema, and damage due to hypoxia or toxins. Signs and symptoms of reversible syndrome of the splenium of the corpus callosum typically include disorientation, confusion, impaired consciousness, and epileptic seizures. Case report: A previously healthy 32-year-old man suffered from weakness, headache, and fever. Subsequently, he developed apathy, ataxia, and inability to walk, and therefore was admitted to the hospital. Cerebrospinal fluid showed protein elevation (0.9 g/l and pleocytosis (232/1 ul. A brain MRI showed hyperintense lesions in the middle of the corpus callosum. The patient was treated with antibiotics, and subsequently, in combination with steroids. Two months later, the hyperintense lesions in the splenium and the basal ganglia had disappeared. Almost seven months since his hospitalization in the Department of Neurology, the patient has returned to his previous employment. He now does not exhibit any mental changes, an optic edema and urological problems have improved. In addition, he is now actively engaged in sports. Conclusion: We have described a case of a 32-year-old man with confusion, ataxia, and inability to stand and walk. The man developed a febrile meningeal syndrome and a hyperintense lesion of the splenium, which lasted for two months. Neurological changes, optic nerve edema, and urinary retention have resolved over the course of seven months. We think that the prolonged but transient lesion of the splenium may have been caused by encephalitis of viral origin.

  17. Fluids and hydration in prolonged endurance performance.

    Science.gov (United States)

    Von Duvillard, Serge P; Braun, William A; Markofski, Melissa; Beneke, Ralph; Leithäuser, Renate

    2004-01-01

    Numerous studies have confirmed that performance can be impaired when athletes are dehydrated. Endurance athletes should drink beverages containing carbohydrate and electrolyte during and after training or competition. Carbohydrates (sugars) favor consumption and Na(+) favors retention of water. Drinking during competition is desirable compared with fluid ingestion after or before training or competition only. Athletes seldom replace fluids fully due to sweat loss. Proper hydration during training or competition will enhance performance, avoid ensuing thermal stress, maintain plasma volume, delay fatigue, and prevent injuries associated with dehydration and sweat loss. In contrast, hyperhydration or overdrinking before, during, and after endurance events may cause Na(+) depletion and may lead to hyponatremia. It is imperative that endurance athletes replace sweat loss via fluid intake containing about 4% to 8% of carbohydrate solution and electrolytes during training or competition. It is recommended that athletes drink about 500 mL of fluid solution 1 to 2 h before an event and continue to consume cool or cold drinks in regular intervals to replace fluid loss due to sweat. For intense prolonged exercise lasting longer than 1 h, athletes should consume between 30 and 60 g/h and drink between 600 and 1200 mL/h of a solution containing carbohydrate and Na(+) (0.5 to 0.7 g/L of fluid). Maintaining proper hydration before, during, and after training and competition will help reduce fluid loss, maintain performance, lower submaximal exercise heart rate, maintain plasma volume, and reduce heat stress, heat exhaustion, and possibly heat stroke.

  18. Acute graft versus host disease

    Directory of Open Access Journals (Sweden)

    Vogelsang Georgia B

    2007-09-01

    Full Text Available Abstract Acute graft-versus-host disease (GVHD occurs after allogeneic hematopoietic stem cell transplant and is a reaction of donor immune cells against host tissues. Activated donor T cells damage host epithelial cells after an inflammatory cascade that begins with the preparative regimen. About 35%–50% of hematopoietic stem cell transplant (HSCT recipients will develop acute GVHD. The exact risk is dependent on the stem cell source, age of the patient, conditioning, and GVHD prophylaxis used. Given the number of transplants performed, we can expect about 5500 patients/year to develop acute GVHD. Patients can have involvement of three organs: skin (rash/dermatitis, liver (hepatitis/jaundice, and gastrointestinal tract (abdominal pain/diarrhea. One or more organs may be involved. GVHD is a clinical diagnosis that may be supported with appropriate biopsies. The reason to pursue a tissue biopsy is to help differentiate from other diagnoses which may mimic GVHD, such as viral infection (hepatitis, colitis or drug reaction (causing skin rash. Acute GVHD is staged and graded (grade 0-IV by the number and extent of organ involvement. Patients with grade III/IV acute GVHD tend to have a poor outcome. Generally the patient is treated by optimizing their immunosuppression and adding methylprednisolone. About 50% of patients will have a solid response to methylprednisolone. If patients progress after 3 days or are not improved after 7 days, they will get salvage (second-line immunosuppressive therapy for which there is currently no standard-of-care. Well-organized clinical trials are imperative to better define second-line therapies for this disease. Additional management issues are attention to wound infections in skin GVHD and fluid/nutrition management in gastrointestinal GVHD. About 50% of patients with acute GVHD will eventually have manifestations of chronic GVHD.

  19. Predictors of prolonged fluoroscopy time in diagnostic coronary angiography.

    Science.gov (United States)

    Adachi, Yusuke; Sakakura, Kenichi; Wada, Hiroshi; Funayama, Hiroshi; Umemoto, Tomio; Momomura, Shin-Ichi; Fujita, Hideo

    2016-07-01

    Prolonged fluoroscopy time during coronary angiography is a major concern for interventional cardiologists as well as for patients. It is unknown which factors affect the prolonged fluoroscopy time. A total of 458 patients who underwent diagnostic coronary angiography were included. The patients who had the highest decile of fluoroscopy time were assigned to the prolonged fluoroscopy group (fluoroscopy time ≥15.7min), while the other patients were assigned to the non-prolonged fluoroscopy group (fluoroscopy time fluoroscopy time. Mean fluoroscopy time in 458 patients was 8.5±5.8min. Median and ranges of fluoroscopy time were 19.0 [15.7-47.0]min in the prolonged fluoroscopy group and 6.0 [2.0-15.3]min in the non-prolonged fluoroscopy group, respectively. The multivariate logistic regression analysis showed that significant predictors of prolonged fluoroscopy time were prior surgery of ascending aorta replacement [odds ratios (OR) 11.46, 95% confidence intervals (CI) 1.53-85.74, p=0.02] and the prevalence of moderate to severe aortic regurgitation (OR 2.83, 95% CI 1.20-6.66, p=0.02). The prior surgery of ascending aorta replacement and moderate to severe aortic regurgitation were significant predictors of the prolonged fluoroscopy time. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  20. Quality of drug label information on QT interval prolongation

    DEFF Research Database (Denmark)

    Warnier, Miriam J; Holtkamp, Frank A; Rutten, Frans H

    2014-01-01

    BACKGROUND: Information regarding QT-prolongation in the drug label may vary between products. This could lead to suboptimal risk minimization strategies. OBJECTIVE: To systematically assess the variation in the extent and content of information on QT prolongation in the summary of product...

  1. The cAMP analogue, dbcAMP affects release of steroid hormones by cultured rabbit ovarian cells and their response to FSH, IGF-I and ghrelin.

    Science.gov (United States)

    Chrenek, Peter; Grossmann, Roland; Sirotkin, Alexander V

    2010-08-25

    The aim of the present study was to examine possible involvement of cAMP-dependent intracellular mechanisms in control of ovarian cell steroidogenesis and its response to hormonal regulators. For this purpose, we examined the influence of administration of dbcAMP, a cAMP analogue (50 microg/animal) in vivo, on release of progesterone, testosterone and estradiol by isolated ovarian fragments, as well their response to hormonal regulators of ovarian steroidogenesis-FSH, IGF-I and ghrelin (all added at doses of 100 ng/ml). It was observed, that administration of dbcAMP resulted reduction in progesterone and testosterone, but not of estradiol release by isolated ovarian fragments. In ovarian tissue isolated from control animals, additions of hormones were able to reduce release of progesterone (FSH, IGF-I and ghrelin) and increase release of testosterone (ghrelin) but did not change estradiol output. Previous administration of dbcAMP modified action of exogenous hormones: it inverted inhibitory action of FSH, IGF-I and ghrelin on progesterone release to stimulatory action and induced stimulatory action of IGF-I on testosterone release and stimulatory effect of FSH on estradiol output. The present observations confirm involvement of peptide hormones FSH, IGF-I and ghrelin in the control of rabbit ovarian steroid hormones release and demonstrate the involvement of cAMP-dependent intracellular mechanisms in down-regulation of rabbit ovarian steroidogenesis and in modification, but not in mediating effect of FSH, IGF-I and ghrelin on ovarian steroid hormones release. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  2. Faecal carriage of ESBL and plasmid-mediated AmpC β-lactamase ...

    African Journals Online (AJOL)

    Spectrum Beta-Lactamase (ESBL) - and plasmid-mediated AmpC β-lactamase prducing bacteria represent a great concern because there are few therapeutic choices. This study was aimed to determine the prevalence of faecal carriage of ESBL ...

  3. Applications of nonvariational finite element methods to Monge--Amp\\`ere type equations

    OpenAIRE

    Pryer, Tristan

    2012-01-01

    The goal of this work is to illustrate the application of the nonvariational finite element method to a specific Monge--Amp\\`ere type nonlinear partial differential equation. The equation we consider is that of prescribed Gauss curvature.

  4. Selective Phosphonylation of 5'-Adenosine Monophosphate (5'-AMP) via Pyrophosphite [PPi(III)

    Science.gov (United States)

    Kaye, Karl; Bryant, David E.; Marriott, Katie E. R.; Ohara, Shohei; Fishwick, Colin W. G.; Kee, Terence P.

    2016-11-01

    We describe here experiments which demonstrate the selective phospho-transfer from a plausibly prebiotic condensed phosphorus (P) salt, pyrophosphite [H2P2O5 2-; PPi(III)], to the phosphate group of 5'-adenosine mono phosphate (5'-AMP). We show further that this P-transfer process is accelerated both by divalent metal ions (M2+) and by organic co-factors such as acetate (AcO-). In this specific case of P-transfer from PPi(III) to 5'-AMP, we show a synergistic enhancement of transfer in the combined presence of M2+ & AcO-. Isotopic labelling studies demonstrate that hydrolysis of the phosphonylated 5'-AMP, [P(III)P(V)-5'-AMP], proceeds via nuceophilic attack of water at the Pi(III) terminus.

  5. Aspirin effects on lymphocyte cyclic AMP levels in normal human subjects.

    Science.gov (United States)

    Snider, D E; Parker, C W

    1976-01-01

    In purified lymphocytes from the peripheral blood of healthy human subjects who had ingested therapeutic doses of aspirin, there was a significant decrease in resting cyclic AMP levels as well as a partial inhibition of the rise in cyclic AMP with isoproterenol or prostaglandin E1. These changes were seen as early as 30 min after aspirin ingestion and did not appear to result from aspirin effects on lymphocyte recovery, purity, viability, or relative number of thymus- or bone marrow-derived lymphocytes. In contrast, the direct addition of aspirin to suspensions of purified peripheral lymphocytes did not significantly alter their cyclic AMP levels. However, an effect of aspirin could be obtained in vitro if aspirin was added to unprocessed whole blood during the dextran sedimentation phase of the cell purification. Thus the effect of aspirin on lymphocyte cyclic AMP metabolism, may be indirect, through other cells present in the peripheral blood. PMID:182720

  6. Occurrence and detection of AmpC β-lactamases among ...

    African Journals Online (AJOL)

    -lactam antibiotics except cefepime and carbapenems. Aim of the study: We aimed to evaluate the presence of AmpC β-lactamase among Enterobacteriaceae isolates separated from patients with nosocomial infections, and to detect the ...

  7. Changes in rodent thyroid hormones and cyclic-AMP following treatment with pineal indolic compounds.

    Science.gov (United States)

    Nir, I; Hirschmann, N; Puder, M; Petrank, J

    1978-05-01

    Treatment of rats with pineal indolic compounds 5-methoxytryptophol, 5-hydroxytryptophol and serotonin brought about a significant increase in serum thyroxine levels, while serotonin and melatonin caused an increase in thyroid cAMP content with corresponding decrease in the gland's hormones. The total quantity of cAMP in the thyroid was also increased by melatonin in the organ culture system. All these findings would indicate that some of the pineal indoleamines elicit a direct action on the thyroid by stimulating the adenyl cyclase activity and intrathyroidal cAMP, bringing about increased release of thyroxine into the blood stream, and that this is usually not accompanied by adequate synthesis in the gland. Our observation that continuous darkness, which stimulates pineal activity, also brought about an increase in cAMP, concours with our finding of a stimulatory effect of the indolic compounds on thyroid hormone release.

  8. Role of the cAMP Pathway in Glucose and Lipid Metabolism.

    Science.gov (United States)

    Ravnskjaer, Kim; Madiraju, Anila; Montminy, Marc

    2016-01-01

    3'-5'-Cyclic adenosine monophosphate (cyclic AMP or cAMP) was first described in 1957 as an intracellular second messenger mediating the effects of glucagon and epinephrine on hepatic glycogenolysis (Berthet et al., J Biol Chem 224(1):463-475, 1957). Since this initial characterization, cAMP has been firmly established as a versatile molecular signal involved in both central and peripheral regulation of energy homeostasis and nutrient partitioning. Many of these effects appear to be mediated at the transcriptional level, in part through the activation of the transcription factor CREB and its coactivators. Here we review current understanding of the mechanisms by which the cAMP signaling pathway triggers metabolic programs in insulin-responsive tissues.

  9. AMP: a science-driven web-based application for the TeraGrid

    Science.gov (United States)

    Woitaszek, M.; Metcalfe, T.; Shorrock, I.

    The Asteroseismic Modeling Portal (AMP) provides a web-based interface for astronomers to run and view simulations that derive the properties of Sun-like stars from observations of their pulsation frequencies. In this paper, we describe the architecture and implementation of AMP, highlighting the lightweight design principles and tools used to produce a functional fully-custom web-based science application in less than a year. Targeted as a TeraGrid science gateway, AMP's architecture and implementation are intended to simplify its orchestration of TeraGrid computational resources. AMP's web-based interface was developed as a traditional standalone database-backed web application using the Python-based Django web development framework, allowing us to leverage the Django framework's capabilities while cleanly separating the user interface development from the grid interface development. We have found this combination of tools flexible and effective for rapid gateway development and deployment.

  10. CB1 receptors down-regulate a cAMP/Epac2/PLC pathway to silence the nerve terminals of cerebellar granule cells.

    Science.gov (United States)

    Alonso, Beatris; Bartolomé-Martín, David; Ferrero, José Javier; Ramírez-Franco, Jorge; Torres, Magdalena; Sánchez-Prieto, José

    2017-08-01

    Cannabinoid receptors mediate short-term retrograde inhibition of neurotransmitter release, as well as long-term depression of synaptic transmission at excitatory synapses. The responses of individual nerve terminals in VGLUT1-pHluorin transfected cerebellar granule cells to cannabinoids have shown that prolonged activation of cannabinoid type 1 receptors (CB1Rs) silences a subpopulation of previously active synaptic boutons. Adopting a combined pharmacological and genetic approach to study the molecular mechanisms of CB1R-induced silencing, we found that adenylyl cyclase inhibition decreases cAMP levels while it increases the number of silent synaptic boutons and occludes the induction of further silencing by the cannabinoid agonist HU-210. Guanine nucleotide exchange proteins directly activated by cAMP (Epac proteins) mediate some of the presynaptic effects of cAMP in the potentiation of synaptic transmission. ESI05, a selective Epac2 inhibitor, and U-73122, the specific inhibitor of phospholipase C (PLC), both augment the number of silent synaptic boutons. Moreover, they abolish the capacity of the Epac activator, 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate, to prevent HU-210-induced silencing consistent with PLC signaling lying downstream of Epac2 proteins. Furthermore, Rab3-interacting molecule (RIM)1α KO cells have many more basally silent synaptic boutons (12.9 ± 3.5%) than wild-type cells (1.1 ± 0.5%). HU-210 induced further silencing in these mutant cells, although 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate only awoke the HU-210-induced silence and not the basally silent synaptic boutons. This behavior can be rescued by expressing RIM1α in RIM1α KO cells, these cells behaving very much like wild-type cells. These findings support the hypothesis that a cAMP/Epac/PLC signaling pathway targeting the release machinery appears to mediate cannabinoid

  11. Adolescent External Iliac Artery Trauma: Recurrent Aneurysmal Dilatation of an Iliofemoral Saphenous Vein Graft Treated by Stent-Grafting

    International Nuclear Information System (INIS)

    Lenton, James; Davies, John; Homer-Vanniasinkam, S.; McPherson, Simon

    2008-01-01

    An adolescent male sustained a severe penetrating injury to the external iliac artery. Emergency surgical revascularization was with a reversed long saphenous vein interposition graft. The primary graft and the subsequent revision graft both became aneurysmal. The second graft aneurysm was successfully excluded by endovascular stent-grafts with medium-term primary patency. A venous graft was used initially rather than a synthetic graft to reduce the risk of infection and the potential problems from future growth. Aneurysmal dilatation of venous grafts in children and adolescents is a rare but recognized complication. To the best of our knowledge, exclusion of these aneurysms with stent-grafts has not been previously reported in the adolescent population.

  12. Vv-AMP1, a ripening induced peptide from Vitis vinifera shows strong antifungal activity

    Directory of Open Access Journals (Sweden)

    Vivier Melané A

    2008-07-01

    Full Text Available Abstract Background Latest research shows that small antimicrobial peptides play a role in the innate defense system of plants. These peptides typically contribute to preformed defense by developing protective barriers around germinating seeds or between different tissue layers within plant organs. The encoding genes could also be upregulated by abiotic and biotic stimuli during active defense processes. The peptides display a broad spectrum of antimicrobial activities. Their potent anti-pathogenic characteristics have ensured that they are promising targets in the medical and agricultural biotechnology sectors. Results A berry specific cDNA sequence designated Vv-AMP1, Vitis vinifera antimicrobial peptide 1, was isolated from Vitis vinifera. Vv-AMP1 encodes for a 77 amino acid peptide that shows sequence homology to the family of plant defensins. Vv-AMP1 is expressed in a tissue specific, developmentally regulated manner, being only expressed in berry tissue at the onset of berry ripening and onwards. Treatment of leaf and berry tissue with biotic or abiotic factors did not lead to increased expression of Vv-AMP1 under the conditions tested. The predicted signal peptide of Vv-AMP1, fused to the green fluorescent protein (GFP, showed that the signal peptide allowed accumulation of its product in the apoplast. Vv-AMP1 peptide, produced in Escherichia coli, had a molecular mass of 5.495 kDa as determined by mass spectrometry. Recombinant Vv-AMP1 was extremely heat-stable and showed strong antifungal activity against a broad spectrum of plant pathogenic fungi, with very high levels of activity against the wilting disease causing pathogens Fusarium oxysporum and Verticillium dahliae. The Vv-AMP1 peptide did not induce morphological changes on the treated fungal hyphae, but instead strongly inhibited hyphal elongation. A propidium iodide uptake assay suggested that the inhibitory activity of Vv-AMP1 might be associated with altering the membrane

  13. A New Therapeutic Strategy for Autosomal Dominant Polycystic Kidney Disease: Activation of AMP Kinase by Metformin

    Science.gov (United States)

    2013-07-01

    of the enzyme’s allosteric activator AMP. Renal ischemia produces energy deprivation in renal tubules and is a powerful stimulus leading to the...Magenheimer BS, et al. (2006) Early embryonic renal tubules of wild-type and polycystic kidney disease kidneys respond to cAMP stimulation with cystic...cells, and Pkd1 flox/ and Pkd1/ temperature-sensitive SV40 large T antigen renal proximal tubule cells (Joly et al., 2006; Shibazaki et al., 2008

  14. Coexpression of ESBL, Amp C and MBL in gram negative bacilli

    OpenAIRE

    Ruturaj M. Kolhapure; Ashwin Kumar; HRV Rajkumar

    2015-01-01

    Background: Resistant bacteria are emerging worldwide as a threat to the favourable outcome of common infections in community and hospital settings. Extended Spectrum Beta-Lactamases (ESBLs), AmpC beta lactamases and Metallo-beta Lactamases (MBL) are the three important mechanism of resistance to beta lactam drugs in the bacteria. The objective of the study was to screen gram negative isolates for co-expression of extended spectrum beta-lactamase, Amp C beta-lactamase and Metallo beta-lactama...

  15. The ever unfolding story of cAMP signalling in trypanosomatids: vive la difference!

    Directory of Open Access Journals (Sweden)

    Daniel Nii Aryee Tagoe

    2015-09-01

    Full Text Available Kinetoplastids are unicellular, eukaryotic, flagellated protozoans containing the eponymous kinetoplast. Within this order, the family of trypanosomatids are responsible for some of the most serious human diseases, including Chagas disease (Trypanosoma cruzi, sleeping sickness (T. brucei spp. and leishmaniasis (Leishmania spp. Although cAMP is produced during the life cycle stages of these parasites, its signalling pathways are very different from those of mammals. The absence of G-protein-coupled recep¬tors, the presence of structurally different adenylyl cyclases, the paucity of known cAMP effector proteins and the stringent need for regulation of cAMP in the small kinetoplastid cells all suggest a significantly different biochemical pathway and likely cell biology. However, each of the main kinetoplastid parasites express four class 1-type cyclic nucleotide-specific phosphodiesterases (PDEA-D, which have highly similar catalytic domains to that of human PDEs. To date, only TbrPDEB, expressed as two slightly different isoforms TbrPDEB1 and B2, has been found to be essential when ablated. Although the genomes contain reasonably well con¬served genes for catalytic and regulatory domains of pro¬tein kinase A, these have been shown to have varied structural and functional roles in the different species. Recent discovery of a role of cAMP/AMP metabolism in a quorum-sensing signalling pathway in T. brucei, and the identification of downstream cAMP Response Proteins (CARPs whose expression levels correlate with sensitivity to PDE inhibitors, suggests a complex signalling cascade. The interplay between the roles of these novel CARPs and the quorum-sensing signalling pathway on cell division and differentiation makes for intriguing cell biology and a new paradigm in cAMP signal transduction, as well as potential targets for trypanosomatid-specific cAMP pathway-based therapeutics.

  16. Cyclic-AMP mediated regulation of ABCB mRNA expression in mussel haemocytes.

    Directory of Open Access Journals (Sweden)

    Silvia Franzellitti

    Full Text Available BACKGROUND: The multixenobiotic resistance system (MXR allows aquatic organisms to cope with their habitat despite high pollution levels by over-expressing membrane and intracellular transporters, including the P-glycoprotein (Pgp. In mammals transcription of the ABCB1 gene encoding Pgp is under cAMP/PKA-mediated regulation; whether this is true in mollusks is not fully clarified. METHODOLOGY/PRINCIPAL FINDINGS: cAMP/PKA regulation and ABCB mRNA expression were assessed in haemocytes from Mediterranean mussels (Mytilus galloprovincialis exposed in vivo for 1 week to 0.3 ng/L fluoxetine (FX alone or in combination with 0.3 ng/L propranolol (PROP. FX significantly decreased cAMP levels and PKA activity, and induced ABCB mRNA down-regulation. FX effects were abolished in the presence of PROP. In vitro experiments using haemocytes treated with physiological agonists (noradrenaline and serotonin and pharmacological modulators (PROP, forskolin, dbcAMP, and H89 of the cAMP/PKA system were performed to obtain clear evidence about the involvement of the signaling pathway in the transcriptional regulation of ABCB. Serotonin (5-HT decreased cAMP levels, PKA activity and ABCB mRNA expression but increased the mRNA levels for a putative 5-HT1 receptor. Interestingly, 5-HT1 was also over-expressed after in vivo exposures to FX. 5-HT effects were counteracted by PROP. Forskolin and dbcAMP increased PKA activity as well as ABCB mRNA expression; the latter effect was abolished in the presence of the PKA inhibitor H89. CONCLUSIONS: This study provides the first direct evidence for the cAMP/PKA-mediated regulation of ABCB transcription in mussels.

  17. Constitutive high expression of chromosomal beta-lactamase in Pseudomonas aeruginosa caused by a new insertion sequence (IS1669) located in ampD

    DEFF Research Database (Denmark)

    Bagge, N.; Ciofu, O.; Hentzer, Morten

    2002-01-01

    resistant, constitutive beta-lactamase-producing variant contained no mutations in ampD, but a point mutation was observed in ampR, resulting in an Asp-135-->Asn change. An identical mutation of AmpR in Enterobacter cloacae has been reported to cause a 450-fold higher AmpC expression. However, in many...

  18. Radiographic analysis of pasteurized autologous bone graft

    International Nuclear Information System (INIS)

    Ahmed, Adel Refaat; Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi

    2003-01-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  19. Radiographic analysis of pasteurized autologous bone graft.

    Science.gov (United States)

    Ahmed, Adel Refaat; Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi

    2003-08-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors.

  20. Radiographic analysis of pasteurized autologous bone graft

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Adel Refaat [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan); Department of Orthopedic Surgery, Alexandria University, Alexandria (Egypt); Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan)

    2003-08-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  1. Strengthening of polycaproamide fibers with grafted polyacrylonitrile

    International Nuclear Information System (INIS)

    Kurilenko, A.I.; Kalinin, V.N.; Kot, L.G.

    1976-01-01

    By direct irradiation of polycaproamide fibers in an acrylonitrile medium, modified fibers with average uniform distribution of discrete grafted polyacrylonitrile molecules along the cross section are obtained. In the range of temperatures from - 196 to -300 deg C, which encompasses all states of grafted polymers, a study is made of how the strength and the deformation properties of the modified fibers are related to the concentration of polyacrylonitrile which has been varied from 0.5 to 0.76% by vol. Also the effects of the grafting process and orientation stretching on the strength and deformation properties of the modified fibers are examined. The presence of polyacrylonitrile produces an additive effect on the strength and deformation properties of the grafted fibers. A quantitative analysis of the results of measurements of the strength of the grafted fibers has been made on the basis of a cross-linked macromolecule model, the nodes in which are formed by the hypermolecular structures and on the assumption that the nodes are the weak points in the cross-linked macromolecule

  2. Long-term results of PTFE grafts.

    Science.gov (United States)

    Hedin, Ulf

    2015-01-01

    Vascular surgeons are essential in "lifeline" creation for hemodialysis patients and should be the central player in any multidisciplinary access service together with nephrologists, dialysis staff and interventional radiology. In this position, access surgeons are involved in complicated clinical decision making regarding primary and secondary access selection, which throughout the last decade has been largely aided, and influenced, by national and international guidelines as well as other initiatives. These recommendations, unanimously and appropriately, advocate the placement of native fistulas over synthetic grafts (the majority grafts from expanded polytetrafluoroethylene, ePTFE, herein referred to as PTFE) based on the superiority of fistulas with respect to complications such as infections and thrombosis. Nevertheless, the use of PTFE grafts for hemodialysis access is an accepted and firmly established alternative to native fistulas where data today reveal unwanted consequences to overinterpretation of established guidelines such as increased catheter use. This information highlights a need for an adjustment of access selection strategies based on patient-centered algorithms. Here, available results on PTFE graft performance in hemodialysis access is recapitulated, with respect to both conventional grafts and technical modifications, and conclude with a modified approach to primary access selection.

  3. Polymer Grafted Nanoparticle-based Oil Dispersants

    Science.gov (United States)

    Kim, Daehak; Krishnamoorti, Ramanan

    2015-03-01

    Particle-based oil dispersants mainly composed of inorganic nanoparticles such as silica nanoparticles are considered as environmentally friendly oil dispersants due to their biocompatibility and relatively low toxicity. The oil-water interfacial tension is reduced when nanoparticles segregate to the oil-water interface and this segregation is improved by grafting interfacially active polymer brushes. In this study, surfactant-like amphiphilic block copolymers were grafted from silica nanoparticles using an atom transfer radical polymerization (ATRP) method in order to increase their interfacial activity. We have studied the interfacial activity of such hybrid nanoparticles using pendant drop interfacial tension measurements, and their structure using small angle X-ray scattering. Amphiphilic copolymer grafted nanoparticles significantly reduced oil-water interfacial tension compared to the interfacial tension reduction induced by homopolymer grafted nanoparticles or the corresponding free ungrafted copolymer. Moreover, hard and stable oil-water emulsions were formed by applying the block copolymer grafted nanoparticles due to the formation of interparticle network structures, which were observed by cryo-scanning electron microscopy (SEM) and small angle neutron scattering (SANS)

  4. Aortic reconstruction with bovine pericardial grafts

    Directory of Open Access Journals (Sweden)

    Silveira Lindemberg Mota

    2003-01-01

    Full Text Available INTRODUCTION: Glutaraldehyde-treated crimped bovine pericardial grafts are currently used in aortic graft surgery. These conduits have become good options for these operations, available in different sizes and shapes and at a low cost. OBJECTIVE:To evaluate the results obtained with bovine pericardial grafts for aortic reconstruction, specially concerning late complications. METHOD: Between January 1995 and January 2002, 57 patients underwent different types of aortic reconstruction operations using bovine pericardial grafts. A total of 29 (50.8% were operated on an urgent basis (mostly acute Stanford A dissection and 28 electively. Thoracotomy was performed in three patients for descending aortic replacement (two patients and aortoplasty with a patch in one. All remaining 54 underwent sternotomy, cardiopulmonary bypass and aortic resection. Deep hypothermia and total circulatory arrest was used in acute dissections and arch operations. RESULTS: Hospital mortality was 17.5%. Follow-up was 24.09 months (18.5 to 29.8 months confidence interval and complication-free actuarial survival curve was 92.3% (standard deviation ± 10.6. Two patients lately developed thoracoabdominal aneurysms following previous DeBakey II dissection and one died from endocarditis. One "patch" aortoplasty patient developed local descending aortic pseudoaneurysm 42 months after surgery. All other patients are asymptomatic and currently clinically evaluated with echocardiography and CT scans, showing no complications. CONCLUSION: Use of bovine pericardial grafts in aortic reconstruction surgery is adequate and safe, with few complications related to the conduits.

  5. Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

    Science.gov (United States)

    Florschutz, Anthony Vatroslav

    Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were

  6. A COMPARATIVE STUDY OF TYMPANOPLASTY USING SLICED CARTILAGE GRAFT VS. TEMPORALIS FASCIA GRAFT

    Directory of Open Access Journals (Sweden)

    Rahul Ashok Telang

    2018-02-01

    Full Text Available BACKGROUND The objective of the study was to compare the hearing improvement after using sliced cartilage graft with that of temporalis fascia and to compare the graft take-up between the two graft materials. MATERIALS AND METHODS A prospective clinical study including 60 patients with chronic mucosal otitis media, who were selected randomly from the outpatient department, after obtaining their consent were divided into 2 groups of 30 each, and evaluated according the study protocol. Their pre-operative audiometry was recorded and both groups of patients underwent surgery with one of the graft materials- temporalis fascia or sliced tragal cartilage with a thickness of 0.5 mm. All patients were regularly followed up and post-operative audiometry was done at 3 months. The hearing improvement in the form of closure of air-bone-gap and graft take-up was analysed statistically. RESULTS The temporalis fascia graft group had a pre-operative ABG of 22.33 ± 6.24 dB and post-operative ABG of 12.33 ± 4.72 dB with hearing improvement of 10.00 dB. The sliced cartilage graft group had a pre-operative ABG of 20.77 ± 5.75 dB and postoperative ABG of 10.50 ± 4.46 dB with hearing improvement of 10.27 dB. In the temporalis fascia group, 28 (93.3% patients had good graft take-up and in the sliced cartilage group 29 (96.7% had good graft take-up. There was statistically significant hearing improvement in both of our study groups but there was no statistically significant difference between the two groups. There was no statistically significant difference in graft take-up also. CONCLUSION Sliced cartilage graft is a good auto-graft material in tympanoplasty, which can give good hearing improvement and has good graft take-up, which is comparable with that of temporalis fascia.

  7. Detection of AmpC beta-lactamases using sodium salicylate.

    Science.gov (United States)

    Kashif, Mona T; Yassin, Aymen S; Hosny, Alaa El-Dien M S

    2012-12-01

    AmpC β-lactamases are enzymes that hydrolyze all β-lactam antibiotics except cefipime and imipenem. Currently, there is no standard phenotypic method for detection of such enzymes. This study aims to report the use of sodium salicylate for AmpC β-lactamases detection and to compare its sensitivity and specificity to other commonly known inhibitors. A total of 135 clinical isolates were used to test the effectiveness of sodium salicylate in detection of plasmid- as well as chromosomally encoded AmpC β-lactamases. All isolates were tested by multiplex PCR testing as well as inhibitor-based methods using cloxacillin, phenylboronic acid and sodium salicylate for the detection of AmpC enzymes. Four isolates were confirmed as producers of plasmid-encoded AmpC β-lactamase and a single isolate was confirmed to have both plasmid and chromosomal genes. Cloxacillin and phenylyboronic acid failed to detect most of the plasmid-encoded enzymes. Sodium salicylate was able to detect the Escherichia coli isolates with plasmid-encoded enzymes in addition to few other isolates that were chromosomally mediated. The sensitivity and specificity of sodium salicylate was 50% and 93%, respectively, higher than those of other known inhibitors. We thus conclude that sodium salicylate can be reliably used as an inhibitor in the detection of plasmid-encoded AmpC enzymes in E. coli. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Dual mechanism for cAMP-dependent modulation of Ca2+ signalling in articular chondrocytes.

    Science.gov (United States)

    D'Andrea, P; Paschini, V; Vittur, F

    1996-09-01

    The ability of cAMP to modulate the actions of Ca(2+)-mobilizing agonists was studied in single Fura-2-loaded pig articular chondrocytes in primary culture. Forskolin and 8-Br-cAMP increased both the frequency and amplitude of Ca2+ oscillations induced by ATP, and, in unstimulated cells, induced single Ca2+ transients or even Ca2+ oscillations. The cAMP-dependent protein kinase inhibitor H89 totally prevented the effect of cAMP-elevating agents on Ca2+ signalling. Forskolin and 8-Br-cAMP promptly increased the rate of Mn2+ quenching, when administered in the presence of ATP, suggesting a potentiation of receptor-mediated Ca2+ influx. In Ca(2+)-free medium, ATP-induced Ca2+ oscillations decreased and stopped after a few cycles: subsequent ATP additions temporarily resumed the activity, an effect that could be mimicked by forskolin. The same agent induced single Ca2+ transients in 42% of the cell population maintained in Ca(2+)-free medium. Thapsigargin prevented Ca2+ responses to both ATP and forskolin. The results indicate a dual mechanism for cAMP-induced potentiation of Ca2+ signalling in articular chondrocytes: an increase of receptor-mediated Ca2+ influx and a positive modulation of intracellular Ca2+ release.

  9. Spatiotemporal regulation of cAMP signaling controls the human trophoblast fusion

    Science.gov (United States)

    Gerbaud, Pascale; Taskén, Kjetil; Pidoux, Guillaume

    2015-01-01

    During human placentation, mononuclear cytotrophoblasts fuse to form multinucleated syncytia ensuring hormonal production and nutrient exchanges between the maternal and fetal circulation. Syncytial formation is essential for the maintenance of pregnancy and for fetal growth. The cAMP signaling pathway is the major route to trigger trophoblast fusion and its activation results in phosphorylation of specific intracellular target proteins, in transcription of fusogenic genes and assembly of macromolecular protein complexes constituting the fusogenic machinery at the plasma membrane. Specificity in cAMP signaling is ensured by generation of localized pools of cAMP controlled by cAMP phosphodiesterases (PDEs) and by discrete spatial and temporal activation of protein kinase A (PKA) in supramolecular signaling clusters inside the cell organized by A-kinase-anchoring proteins (AKAPs) and by organization of signal termination by protein phosphatases (PPs). Here we present original observations on the available components of the cAMP signaling pathway in the human placenta including PKA, PDE, and PP isoforms as well as AKAPs. We continue to discuss the current knowledge of the spatiotemporal regulation of cAMP signaling triggering trophoblast fusion. PMID:26441659

  10. Anoctamin 9/TMEM16J is a cation channel activated by cAMP/PKA signal.

    Science.gov (United States)

    Kim, Hyungsup; Kim, Hyesu; Lee, Jesun; Lee, Byeongjun; Kim, Hee-Ryang; Jung, Jooyoung; Lee, Mi-Ock; Oh, Uhtaek

    2018-05-01

    Anoctamins (ANOs) are multifunctional membrane proteins that consist of 10 homologs. ANO1 (TMEM16A) and ANO2 (TMEM16B) are anion channels activated by intracellular calcium that meditate numerous physiological functions. ANO6 is a scramblase that redistributes phospholipids across the cell membrane. The other homologs are not well characterized. We found ANO9/TMEM16J is a cation channel activated by a cAMP-dependent protein kinase A (PKA). Intracellular cAMP-activated robust currents in whole cells expressing ANO9, which were inhibited by a PKA blocker. A cholera toxin that persistently stimulated adenylate cyclase activated ANO9 as did the application of PKA. The cAMP-induced ANO9 currents were permeable to cations. The cAMP-dependent ANO9 currents were augmented by intracellular Ca 2+ . Ano9 transcripts were predominant in the intestines. Human intestinal SW480 cells expressed high levels of Ano9 transcripts and showed PKA inhibitor-reversible cAMP-dependent currents. We conclude that ANO9 is a cation channel activated by a cAMP/PKA pathway and could play a role in intestine function. Copyright © 2017. Published by Elsevier Ltd.

  11. The Impact of Total Ischemic Time, Donor Age and the Pathway of Donor Death on Graft Outcomes After Deceased Donor Kidney Transplantation.

    Science.gov (United States)

    Wong, Germaine; Teixeira-Pinto, Armando; Chapman, Jeremy R; Craig, Jonathan C; Pleass, Henry; McDonald, Stephen; Lim, Wai H

    2017-06-01

    Prolonged ischemia is a known risk factor for delayed graft function (DGF) and its interaction with donor characteristics, the pathways of donor death, and graft outcomes may have important implications for allocation policies. Using data from the Australian and New Zealand Dialysis and Transplant registry (1994-2013), we examined the relationship between total ischemic time with graft outcomes among recipients who received their first deceased donor kidney transplants. Total ischemic time (in hours) was defined as the time of the donor renal artery interruption or aortic clamp, until the time of release of the clamp on the renal artery in the recipient. A total of 7542 recipients were followed up over a median follow-up time of 5.3 years (interquartile range of 8.2 years). Of these, 1823 (24.6%) experienced DGF and 2553 (33.9%) experienced allograft loss. Recipients with total ischemic time of 14 hours or longer experienced an increased odd of DGF compared with those with total ischemic time less than 14 hours. This effect was most marked among those with older donors (P value for interaction = 0.01). There was a significant interaction between total ischemic time, donor age, and graft loss (P value for interaction = 0.03). There was on average, a 9% increase in the overall risk of graft loss per hour increase in the total ischemic time (adjusted hazard ratio, 1.09; 95% confidence interval, 1.01-1.18; P = 0.02) in recipients with older donation after circulatory death grafts. There is a clinically important interaction between donor age, the pathway of donor death, and total ischemic time on graft outcomes, such that the duration of ischemic time has the greatest impact on graft survival in recipients with older donation after circulatory death kidneys.

  12. Meshed split skin graft for extensive vitiligo

    Directory of Open Access Journals (Sweden)

    Srinivas C

    2004-05-01

    Full Text Available A 30 year old female presented with generalized stable vitiligo involving large areas of the body. Since large areas were to be treated it was decided to do meshed split skin graft. A phototoxic blister over recipient site was induced by applying 8 MOP solution followed by exposure to UVA. The split skin graft was harvested from donor area by Padgett dermatome which was meshed by an ampligreffe to increase the size of the graft by 4 times. Significant pigmentation of the depigmented skin was seen after 5 months. This procedure helps to cover large recipient areas, when pigmented donor skin is limited with minimal risk of scarring. Phototoxic blister enables easy separation of epidermis thus saving time required for dermabrasion from recipient site.

  13. [Localized purpura revealing vascular prosthetic graft infection].

    Science.gov (United States)

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  14. Grafting Polymer Loops onto Functionalized Nanotubes: Monitoring Grafting and Loop Formation

    Energy Technology Data Exchange (ETDEWEB)

    Ashcraft, Earl C [ORNL; Ji, Haining [ORNL; Mays, Jimmy [ORNL; Dadmun, Mark D [ORNL

    2011-01-01

    Polystyrene functionalized at both ends (telechelic polymer) with epoxide groups (epoxy PS epoxy) was reacted with carboxylated multiwall carbon nanotubes (COOH MWNT) in solution in order to graft polymer chains at both ends onto the MWNT surface, forming loops. FT-IR spectroscopy was employed to monitor the formation of aromatic esters and to quantify the amount of telechelic grafted to the nanotube surface as a function of reaction time. When the samples were further annealed in the melt, an increase in the aromatic ester peak was observed, indicating that the unreacted chain ends further grafted to MWNT surfaces to form loops. By reacting the grafted nanotube samples further with monocarboxy terminated poly(4-methylstyrene) (COOH P4MS), the amount of epoxy PS epoxy that had only reacted at one end was determined. Reaction rate analysis indicates that that the grafting of epoxy PS epoxy to the nanotube surface is reaction controlled, as the FT-IR spectroscopy signal grows as a function of approximately t0.3. These studies exemplify how FT-IR spectroscopy can be used as a novel technique to quantify the amount of grafted polymer, grafting rate, and percent of difunctional polymers that form loops, and provide a method to create loop covered nanoparticles.

  15. Expansion techniques for skin grafts: comparison between mesh and Meek island (sandwich-) grafts.

    Science.gov (United States)

    Kreis, R W; Mackie, D P; Hermans, R R; Vloemans, A R

    1994-01-01

    In skin grafting operations for patients with extensive burn injuries, mesh techniques are often employed to enlarge the effective surface area covered by autografts. However, substantial strips of autograft are required and the distribution of autograft elements on the wound surface is relatively uneconomical. An alternative technique for expanding autografts, first described by Meek in 1958, makes use of a special dermatome and prefolded gauzes to obtain a regular expansion of autograft squares from small pieces of split skin grafts. In a simple in vitro experiment using allograft skin, the expansion ratio obtained with the Meek micrograft technique was measured at almost 1:9. In contrast, the expansion ratio obtained with allograft meshed '1:6' with a Zimmer Dermatome II was measured at 1:4. The maximum distance between the graft elements obtained with the Meek technique was 9 mm, compared to a maximal distance between the strands of the mesh graft of 12 mm. The Meek technique is a useful alternative to mesh grafts when donor sites are limited. Clinical experience suggests that Meek grafts are also particularly suitable for grafting on granulating wounds under poor conditions.

  16. Effect of nicotinamide on early graft failure following intraportal islet transplantation

    Science.gov (United States)

    Jung, Da-Yeon; Park, Jae Berm; Joo, Sung-Yeon; Joh, Jae-Won; Kwon, Choon-Hyuck; Kwon, Ghee-Young

    2009-01-01

    Intraportal islet transplantation (IPIT) may potentially cure Type 1 diabetes mellitus; however, graft failure in the early post-transplantation period presents a major obstacle. In this study, we tested the ability of nicotinamide to prevent early islet destruction in a syngeneic mouse model. Mice (C57BL/6) with chemically-induced diabetes received intraportal transplants of syngeneic islet tissue in various doses. Islets were cultured for 24 h in medium with or without 10 mM nicotinamide supplementation. Following IPIT, islet function was confirmed by an intraperitoneal glucose tolerance test (IPGTT) and hepatectomy. The effects of nicotinamide were evaluated by blood glucose concentration, serum monocyte chemoattractant protein-1 (MCP-1) concentration, and immunohistology at 3 h and 24 h after IPIT. Among the various islet doses, an infusion of 300 syngeneic islets treated with nicotinamide exhibited the greatest differences in glucose tolerance between recipients of treated and untreated (i.e., control) islets. One day after 300 islet equivalent (IEQ) transplantation, islets treated with nicotinamide were better granulated than the untreated islets (P = 0.01), and the recipients displayed a slight decrease in serum MCP-1 concentration, as compared to controls. After 15 days, recipients of nicotinamide-pretreated islets showed higher levels of graft function (as measured by IPGTT) than controls. The pretreatment also prolonged graft survival (> 100 days) and function; these were confirmed by partial hepatectomy, which led to the recurrence of diabetes. Pretreatment of islet grafts with nicotinamide may prevent their deterioration on the early period following IPIT in a syngeneic mouse model. PMID:19641379

  17. Redox regulation of the AMP-activated protein kinase.

    Directory of Open Access Journals (Sweden)

    Yingying Han

    2010-11-01

    Full Text Available Redox state is a critical determinant of cell function, and any major imbalances can cause severe damage or death.The aim of this study is to determine if AMP-activated protein kinase (AMPK, a cellular energy sensor, is activated by oxidants generated by Berberine in endothelial cells (EC.Bovine aortic endothelial cells (BAEC were exposed to Berberine. AMPK activity and reactive oxygen species were monitored after the incubation.In BAEC, Berberine caused a dose- and time-dependent increase in the phosphorylation of AMPK at Thr172 and acetyl CoA carboxylase (ACC at Ser79, a well characterized downstream target of AMPK. Concomitantly, Berberine increased peroxynitrite, a potent oxidant formed by simultaneous generation of superoxide and nitric oxide. Pre-incubation of BAEC with anti-oxidants markedly attenuated Berberine-enhanced phosphorylation of both AMPK and ACC. Consistently, adenoviral expression of superoxide dismutase and pretreatment of L-N(G-Nitroarginine methyl ester (L-NAME; a non-selective NOS inhibitor blunted Berberine-induced phosphorylation of AMPK. Furthermore, mitochondria-targeted tempol (mito-tempol pretreatment or expression of uncoupling protein attenuated AMPK activation caused by Berberine. Depletion of mitochondria abolished the effects of Berberine on AMPK in EC. Finally, Berberine significantly increased the phosphorylation of LKB1 at Ser307 and gene silencing of LKB1 attenuated Berberine-enhanced AMPK Thr172 phosphorylation in BAEC.Our results suggest that mitochondria-derived superoxide anions and peroxynitrite are required for Berberine-induced AMPK activation in endothelial cells.

  18. Different cAMP sources are critically involved in G protein-coupled receptor CRHR1 signaling.

    Science.gov (United States)

    Inda, Carolina; Dos Santos Claro, Paula A; Bonfiglio, Juan J; Senin, Sergio A; Maccarrone, Giuseppina; Turck, Christoph W; Silberstein, Susana

    2016-07-18

    Corticotropin-releasing hormone receptor 1 (CRHR1) activates G protein-dependent and internalization-dependent signaling mechanisms. Here, we report that the cyclic AMP (cAMP) response of CRHR1 in physiologically relevant scenarios engages separate cAMP sources, involving the atypical soluble adenylyl cyclase (sAC) in addition to transmembrane adenylyl cyclases (tmACs). cAMP produced by tmACs and sAC is required for the acute phase of extracellular signal regulated kinase 1/2 activation triggered by CRH-stimulated CRHR1, but only sAC activity is essential for the sustained internalization-dependent phase. Thus, different cAMP sources are involved in different signaling mechanisms. Examination of the cAMP response revealed that CRH-activated CRHR1 generates cAMP after endocytosis. Characterizing CRHR1 signaling uncovered a specific link between CRH-activated CRHR1, sAC, and endosome-based signaling. We provide evidence of sAC being involved in an endocytosis-dependent cAMP response, strengthening the emerging model of GPCR signaling in which the cAMP response does not occur exclusively at the plasma membrane and introducing the notion of sAC as an alternative source of cAMP. © 2016 Inda et al.

  19. The effect of adenosine 5'-monophosphate (AMP) on tenderness, microstructure and chemical-physical index of duck breast meat.

    Science.gov (United States)

    Wang, Daoying; Deng, Shaoying; Zhang, Muhan; Geng, Zhiming; Sun, Chong; Bian, Huan; Xu, Weimin; Zhu, Yongzhi; Liu, Fang; Wu, Haihong

    2016-03-30

    Adenosine 5'-monophosphate (AMP) is often used in meat and poultry soups as a flavor enhancer (flavor modifier), or as food additives for specific nutritional purposes. Our previous research as well as evidence from others showed that actomyosin could be dissociated into myosin and actin by AMP in extracted muscle solution. However, there is no report available on the application of AMP to dissociate actomyosin and to improve meat tenderness. The objectives of this study were to evaluate the effect of AMP on duck meat tenderness and other quality traits and to explore the mechanism of the action of AMP on meat tenderness. Duck breast muscle was treated with 0, 10, 20, 30, 40 mmol L(-1) AMP at 5 °C for 10 h and examined for shear force, microstructure, actomyosin dissociation, myofibril fragmentation index (MFI), pH, water content, cooking loss, CIE* color (L*, a*, b*), inosine monophosphate (IMP) and free amino acid (FAA) contents. Results showed that shear force, cooking loss, L* and b* of the muscles significantly decreased after AMP treatment (P 0.05), and muscle shrinkage in transverse and longitudinal directions were restrained after AMP treatment. The results suggest that AMP could notably improve meat tenderness, and this effect was probably mainly through increasing muscle pH, promoting actomyosin dissociation and disrupting the Z-line; meanwhile, the conversion of AMP to IMP may contribute to the flavor of meat. © 2015 Society of Chemical Industry.

  20. Coracoid graft positioning in the Latarjet procedure.

    Science.gov (United States)

    Kraus, Tobias M; Graveleau, Nicolas; Bohu, Yoann; Pansard, Erwan; Klouche, Shahnaz; Hardy, Philippe

    2016-02-01

    The success of shoulder stabilization with the Latarjet procedure depends on the correct positioning of the coracoid graft at the glenoid. The aim of this study was to assess intra-observer reproducibility and inter-observer reproducibility of a new standardized CT scan analysis for coracoid graft positioning in the axial plane after the Latarjet procedure and to assess the positioning in the study group. A consecutive series of 27 patients (22 men, 5 woman, 26.1 ± 6.4 years-13 right, 14 left shoulders) were followed up with CT scans between 2010 and 2012. The analysis of the CT scans (2.4 ± 0.7 months postoperatively) was performed with Osirix™ software. The assessment included two criteria in the axial plane: relation of the graft to the articular surface of the glenoid and impingement of the graft with the maximal humeral head circumference. Grafts were judged to be lateral, congruent, flush or medial. The strength of intra-observer agreement and inter-observer agreement was measured by the Kappa coefficient. The Kappa coefficient for intra-observer agreement was "substantial" (K = 0.64 ± 0.14, z = 4.6) to "almost perfect" (K = 0.81 ± 0.14, z = 5.7). The Kappa coefficient for inter-observer variability was "substantial" (K = 0.59 ± 0.14, z = 4.3) to "almost perfect" (K = 0.89 ± 0.14, z = 6.0). In our study, in the axial plane, 3 (11 %) transplants were lateral; 6 (22 %) transplants were congruent; 16 (60 %) flush and 2 (7 %) medial. This standardized CT scan analysis after Latarjet procedure has shown to accurately describe graft positioning in the axial plane with both good intra-observer reproducibility and inter-observer reproducibility. Case series, treatment study, Level IV.

  1. Autologous Fat Grafting for Whole Breast Reconstruction

    Directory of Open Access Journals (Sweden)

    Benjamin H. L. Howes, MBBS

    2014-03-01

    Full Text Available Summary: This is the first reported case of a patient who had a single-stage large-volume breast reconstruction with autologous fat grafting, following rotation flap approach (RoFA mastectomy. The purpose of this case study was to evaluate the viability of reconstruction of the breast by autologous fat grafting alone, in the context of RoFA mastectomy. The hypothesis was that there would be minimal interval loss of autologous fat on the whole breast reconstruction side. Right RoFA mastectomy was used for resection of an invasive primary breast cancer and resulted in the right breast skin envelope. Eleven months later, the patient underwent grafting of 400 ml of autologous fat into the skin envelope and underlying pectoralis major muscle. Outcome was assessed by using a validated 3D laser scan technique for quantitative breast volume measurement. Other outcome measures included the BREAST-Q questionnaire and 2D clinical photography. At 12-month follow-up, the patient was observed to have maintenance of volume of the reconstructed breast. Her BREAST-Q scores were markedly improved compared with before fat grafting, and there was observable improvement in shape, contour, and symmetry on 2D clinical photography. The 2 new techniques, RoFA mastectomy and large-volume single-stage autologous fat grafting, were used in combination to achieve a satisfactory postmastectomy breast reconstruction. Novel tools for measurement of outcome were the 3D whole-body laser scanner and BREAST-Q questionnaire. This case demonstrates the potential for the use of fat grafting for reconstruction. Outcomes in a larger patient populations are needed to confirm these findings.

  2. Relationship between 5-aminoimidazole-4-carboxamide-ribotide and AMP-activated protein kinase activity in the perfused mouse heart.

    Science.gov (United States)

    Zhang, Li; Frederich, Markus; He, Huamei; Balschi, James A

    2006-03-01

    AMP-activated protein kinase (AMPK) is a cellular energy sensor whose activity responds to AMP concentration ([AMP]). An agent that activates AMPK in cells is 5-aminoimidazole-4-carboxamide-1-riboside (AICA-riboside). Phosphorylated AICA-riboside or AICA-ribotide (ZMP) is an AMP analog. It is generally assumed that ZMP accumulation does not alter [AMP]. Additionally, the effect of AICA-riboside on AMPK activity of the heart is uncertain. Two hypotheses were tested in the isolated mouse heart: 1) sufficient ZMP concentration ([ZMP]) forms to increase AMPK activity, and 2) [ZMP] accumulation increases [AMP]. Perfusion of isolated mouse hearts with Krebs-Henseleit buffer containing 0.15-2 mM AICA-riboside concentration resulted in [ZMP] of 2-8 mM. ZMP accumulation reduced phosphocreatine concentration, which increased cytosolic [AMP]. In hearts with [ZMP] less than approximately 3 mM, in vivo AMPK allosteric activity effects of ZMP were observed; AMPK phosphorylation and [AMP] were not increased. With [ZMP] between 3 and 5 mM, in vitro AMPK activity and phosphorylation increased with unchanged [AMP]. This occurred in hearts perfused with 0.25 mM AICA-riboside for 48 min and 0.5 mM AICA-riboside for 24 min. The [ZMP] resulting in 50% AMPK activity (covalent phosphorylation of AMPK) was 4.1 +/- 0.6 mM. Hearts with [ZMP] >5 mM displayed increased [AMP] and AMPK activity that was not different from hearts with similar [AMP] with no [ZMP]; the half-maximal activity of AMP was 5.6 +/- 1.6 microM. Thus, in mouse hearts, AICA-riboside was metabolized to [ZMP] adequately to increase AMPK activity. Higher [ZMP] also increased cytosolic [AMP], which affects AMPK activity.

  3. Risk factors, treatments, and outcomes associated with prolonged hyperemesis gravidarum.

    Science.gov (United States)

    Mullin, Patrick M; Ching, ChunYu; Schoenberg, Frederic; MacGibbon, Kimber; Romero, Roberto; Goodwin, T Murphy; Fejzo, Marlena S

    2012-06-01

    To identify factors associated with prolonged Hyperemesis Gravidarum (HG). About 395 women completed a survey regarding pre-existing conditions, treatments and outcomes. Responses were compared using two-sided t-tests or the F-test. Participants with prolonged HG are slightly younger and weigh more. Pre-existing factors associated with prolonged HG include allergies and a restrictive diet. Prolonged HG is associated with hematemesis, dizziness, fainting and antiemetic treatment. Following pregnancy, those with prolonged HG reported more posttraumatic stress, motion sickness, muscle weakness and infants with irritability, severe colic and growth restriction. Multiple pre-existing conditions and poor maternal and infant outcomes were associated with prolonged HG. The most significant condition prior to pregnancy was allergies suggesting a possible autoimmune component affecting duration of HG. In addition, the most significant lifestyle choice linked to prolonged HG was a restrictive diet. Future research is needed to determine whether a change in diet prior to pregnancy may lead to a shorter duration of HG and its associated outcomes.

  4. [Prolonged fever: specific issues in the young adult population].

    Science.gov (United States)

    Carmoi, T; Grateau, G; Billhot, M; Dumas, G; Biale, L; Perrot, G; Algayres, J-P

    2010-12-01

    Early studies on prolonged fever date back to the 1960s. Fifty years later, prolonged unexplained fever remains a diagnostic challenge to the general internists. Although the aetiologies of prolonged fevers have not changed much in the general population, the distribution between the various causes is not the same anymore. A regular decrease in infectious and neoplastic causes is noticed whatever the age. Prolonged fevers related to inflammatory disorders and fevers that remain of unknown origin still represent approximately 30 to 50% of the cases. In the young adult population, as in the older patients, prolonged fevers can be attributed to four groups: infection, inflammation, neoplasic and other aetiologies (including drug-related fevers). In the young adult population, the management of prolonged fever presents some specific issues that are the purpose of this review coupled with our own experience. The prognosis of undiagnosed prolonged fever is usually favourable, as a life-threatening aetiology is exceptionally diagnosed during the follow-up if the initial management was complete and accurate. Copyright © 2010 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  5. Risk factors, treatments, and outcomes associated with prolonged hyperemesis gravidarum

    Science.gov (United States)

    Mullin, PM; Ching, CY; Shoenberg, F; MacGibbon, K; Romero, R; Goodwin, TM; Fejzo, MS

    2013-01-01

    Objective To identify factors associated with prolonged Hyperemesis Gravidarum (HG). Study Design About 395 women completed a survey regarding pre-existing conditions, treatments and outcomes. Responses were compared using two-sided t-test or the F-test. Results Participants with prolongs HG are slightly younger and weight more. Pre-existing factors associated with prolonged HG include allergies and a restrictive diet. Prolonged HG is associated with hematemesis, dizziness, fainting and antiemetic treatment. Following pregnancy, those with prolonged HG reported more posttraumatic stress, motion sickness, muscle weakness and infants with irritability, severe colic and growth restriction. Conclusion Multiple pre-existing conditions and poor maternal and infant outcomes were associated with prolonged HG. The most significant condition prior to pregnancy was allergies suggesting a possible autoimmune component affecting duration of HG. In addition, the most significant lifestyle choice linked to prolonged HG was a restrictive diet. Future research is needed to determine whether a change in diet prior to pregnancy may lead to a shorter duration of HG and its associated outcomes. PMID:21916750

  6. Utilization of arterial grafts in foot replantation

    Directory of Open Access Journals (Sweden)

    Selami S. Sirvan, MD

    2017-03-01

    Full Text Available Our subject is a 36-year-old man who presented to the emergency department with bilateral lower extremity amputation at the level of the distal third of the tibia after a car accident. Surgery was planned for below-knee amputation of the right lower extremity and replantation of the left foot. The arteries dissected from the iatrogenically amputated segment were used as grafts to repair vascular gaps during the replantation. The patient's follow-up had been problem free. We concluded that whenever possible, amputated parts unsuitable for replantation should be examined thoroughly and neurovascular structures that might be used as grafts should be preserved.

  7. Utilization of arterial grafts in foot replantation.

    Science.gov (United States)

    Sirvan, Selami S; Dagdelen, Daghan; Akgun Demir, Isil; Cezairlioglu, Mecd Atif; Sezer, Hasan Basri; Karsidag, Semra

    2017-03-01

    Our subject is a 36-year-old man who presented to the emergency department with bilateral lower extremity amputation at the level of the distal third of the tibia after a car accident. Surgery was planned for below-knee amputation of the right lower extremity and replantation of the left foot. The arteries dissected from the iatrogenically amputated segment were used as grafts to repair vascular gaps during the replantation. The patient's follow-up had been problem free. We concluded that whenever possible, amputated parts unsuitable for replantation should be examined thoroughly and neurovascular structures that might be used as grafts should be preserved.

  8. Graft copolimerization of hydrophilic monomers onto irradiated polypropylene fibers

    International Nuclear Information System (INIS)

    Sundardi, F.

    1978-01-01

    A method of graft copolymerization of hydrophilic monomers, such as 1-vinyl-2-pyrrolidone, acrylonitrile, acrylic acid, and acrylamide, onto irradiated polypropylene fibers has been studied. γ ray as well as electron beam were employed for the irradiation processes. Graft-copolymerization kinetics and the properties of grafted fibers have been investigated. Moisture regain, dyes absorption, and melting point of the grafted fibers were found to increase with the increasing of the degree of grafting. Polypropylene for 1-vinyl-2-pyrrolidone grafted fibers showed excellent dye absorption for almost all kinds of dyes such as direct, basic, acid, reactive, disper, and naphthol dyes. However, for polypropylene acrylic acid grafted fibers, the colorfastness to washing was found to be unsatisfactory. The colorfastness to washing for polypropylene 1-vinyl-2-pyrrolidone grafted fibers was found to be fairly good for certain types of dyes such as vat and naphthol dyes. (author)

  9. Tympanoplasty: does dry or wet temporalis fascia graft matter?

    Science.gov (United States)

    Singh, G B; Kumar, D; Aggarwal, K; Garg, S; Arora, R; Kumar, S

    2016-08-01

    To evaluate the success rate of dry and wet temporalis fascia grafts in type I underlay tympanoplasty. A prospective, randomised study was conducted. One hundred adult patients (males and females) with chronic suppurative otitis media (mucosal type) were divided into 2 groups of 50 each: one group underwent dry graft tympanoplasty and the other underwent wet graft tympanoplasty. Fibroblast count was calculated in dry and wet grafts. The dry graft and wet graft groups had overall surgical success rates of 82 and 90 per cent, respectively; this finding was not statistically significant. A statistically significant high fibroblast count was observed in wet grafts, but it did not correlate with surgical success. A dry or wet temporalis fascia graft does not influence the outcome of tympanoplasty type I.

  10. Sulfonated hydrocarbon graft architectures for cation exchange membranes

    DEFF Research Database (Denmark)

    Nielsen, Mads Møller; Jankova Atanasova, Katja; Hvilsted, Søren

    2013-01-01

    A synthetic strategy to hydrocarbon graft architectures prepared from a commercial polysulfone and aimed as ion exchange membrane material is proposed. Polystyrene is grafted from a polysulfone macroinitiator by atom transfer radical polymerization, and subsequently sulfonated with acetyl sulfate...

  11. Requirement of cAMP signaling for Schwann cell differentiation restricts the onset of myelination.

    Science.gov (United States)

    Bacallao, Ketty; Monje, Paula V

    2015-01-01

    Isolated Schwann cells (SCs) respond to cAMP elevation by adopting a differentiated post-mitotic state that exhibits high levels of Krox-20, a transcriptional enhancer of myelination, and mature SC markers such as the myelin lipid galactocerebroside (O1). To address how cAMP controls myelination, we performed a series of cell culture experiments which compared the differentiating responses of isolated and axon-related SCs to cAMP analogs and ascorbate, a known inducer of axon ensheathment, basal lamina formation and myelination. In axon-related SCs, cAMP induced the expression of Krox-20 and O1 without a concomitant increase in the expression of myelin basic protein (MBP) and without promoting axon ensheathment, collagen synthesis or basal lamina assembly. When cAMP was provided together with ascorbate, a dramatic enhancement of MBP expression occurred, indicating that cAMP primes SCs to form myelin only under conditions supportive of basal lamina formation. Experiments using a combination of cell permeable cAMP analogs and type-selective adenylyl cyclase (AC) agonists and antagonists revealed that selective transmembrane AC (tmAC) activation with forskolin was not sufficient for full SC differentiation and that the attainment of an O1 positive state also relied on the activity of the soluble AC (sAC), a bicarbonate sensor that is insensitive to forskolin and GPCR activation. Pharmacological and immunological evidence indicated that SCs expressed sAC and that sAC activity was required for morphological differentiation and the expression of myelin markers such as O1 and protein zero. To conclude, our data indicates that cAMP did not directly drive myelination but rather the transition into an O1 positive state, which is perhaps the most critical cAMP-dependent rate limiting step for the onset of myelination. The temporally restricted role of cAMP in inducing differentiation independently of basal lamina formation provides a clear example of the uncoupling of signals

  12. Requirement of cAMP signaling for Schwann cell differentiation restricts the onset of myelination.

    Directory of Open Access Journals (Sweden)

    Ketty Bacallao

    Full Text Available Isolated Schwann cells (SCs respond to cAMP elevation by adopting a differentiated post-mitotic state that exhibits high levels of Krox-20, a transcriptional enhancer of myelination, and mature SC markers such as the myelin lipid galactocerebroside (O1. To address how cAMP controls myelination, we performed a series of cell culture experiments which compared the differentiating responses of isolated and axon-related SCs to cAMP analogs and ascorbate, a known inducer of axon ensheathment, basal lamina formation and myelination. In axon-related SCs, cAMP induced the expression of Krox-20 and O1 without a concomitant increase in the expression of myelin basic protein (MBP and without promoting axon ensheathment, collagen synthesis or basal lamina assembly. When cAMP was provided together with ascorbate, a dramatic enhancement of MBP expression occurred, indicating that cAMP primes SCs to form myelin only under conditions supportive of basal lamina formation. Experiments using a combination of cell permeable cAMP analogs and type-selective adenylyl cyclase (AC agonists and antagonists revealed that selective transmembrane AC (tmAC activation with forskolin was not sufficient for full SC differentiation and that the attainment of an O1 positive state also relied on the activity of the soluble AC (sAC, a bicarbonate sensor that is insensitive to forskolin and GPCR activation. Pharmacological and immunological evidence indicated that SCs expressed sAC and that sAC activity was required for morphological differentiation and the expression of myelin markers such as O1 and protein zero. To conclude, our data indicates that cAMP did not directly drive myelination but rather the transition into an O1 positive state, which is perhaps the most critical cAMP-dependent rate limiting step for the onset of myelination. The temporally restricted role of cAMP in inducing differentiation independently of basal lamina formation provides a clear example of the

  13. Control of cell volume in the J774 macrophage by microtubule disassembly and cyclic AMP

    Science.gov (United States)

    Melmed, RN; Karanian, PJ; Berlin, RD

    1981-01-01

    We have explored the possibilities that cell volume is regulated by the status of microtubule assembly and cyclic AMP metabolism and may be coordinated with shape change. Treatment of J774.2 mouse macrophages with colchicine caused rapid microtubule disassembly and was associated with a striking increase (from 15-20 to more than 90 percent) in the proportion of cells with a large protuberance at one pole. This provided a simple experimental system in which shape changes occurred in virtually an entire cell population in suspension. Parallel changes in cell volume could then be quantified by isotope dilution techniques. We found that the shape change caused by colchicine was accompanied by a decrease in cell volume of approximately 20 percent. Nocodozole, but not lumicolchicine, caused identical changes in both cell shape and cell volume. The volume loss was not due to cell lysis nor to inhibition of pinocytosis. The mechanism of volume loss was also examined. Colchicine induced a small but reproducible increase in activity of the ouabain-sensitive Na(+), K(+)-dependent ATPase. However, inhibition of this enzyme/transport system by ouabain did not change cell volume nor did it block the colchicines-induced decrease in volume. One the other hand, SITS (4’acetamido, 4-isothiocyano 2,2’ disulfonic acid stilbene), an inhibitor of anion transport, inhibited the effects of colchicines, thus suggesting a role for an anion transport system in cell volume regulation. Because colchicine is known to activate adenylate cyclase in several systems and because cell shape changes are often induced by hormones that elevate cyclic AMP, we also examined the effects of cyclic AMP on cell volume. Agents that act to increase syclic AMP (cholera toxin, which activates adenylate cyclase; IBMX, and inhibitor of phosphodiesterase; and dibutyryl cyclic AMP) all caused a volume decrease comparable to that of colchicine. To define the effective metabolic pathway, we studied two mutants of J

  14. Lycopene and flesh colour differences in grafted and non-grafted watermelon

    OpenAIRE

    Fekete D.; Stéger-Máté M.; Bőhm V.; Balázs G.; Kappel N.

    2015-01-01

    The experiment was carried out in three regions in Hungary (Jászszentandrás, Cece, Újkígyós) in 2013 to determine the fruit quality of grafted watermelon (Citrullus lanatus Thunb.). The “RX 467” seedless watermelon variety was grafted on two commercial rootstocks “FR STRONG” [Lagenaria siceraria (Mol.) Standl.] and “RS 841” (Cucurbita maxima Duchesne × Cucurbita moschata Duchesne). The lycopene and flesh colours are important quality characteristics even of the selfrooted and grafted watermel...

  15. Cambial Isoperoxidases Related to Graft Compatibility in Pear-Quince Graft Combinations

    OpenAIRE

    GÜLEN*, Hatice

    2005-01-01

    This study was initiated to survey the graft compatibility characteristics of some selected quince clones known as "S.Ö." with regard to isoperoxidase markers. Compatible (Beurre Hardy = BH) and incompatible (Bartlett = BT) pear cultivars were grafted on quince A (QA) and 13 S.Ö. quince clones by T budding. Bark tissues were collected from the union (4, 8 and 12 weeks after grafting) and from unbudded rootstocks in addition to current-year shoots of 2 pear scions to investigate 2 an...

  16. Striatal grafts in a rat model of Huntington's disease

    DEFF Research Database (Denmark)

    Guzman, R; Meyer, M; Lövblad, K O

    1999-01-01

    Survival and integration into the host brain of grafted tissue are crucial factors in neurotransplantation approaches. The present study explored the feasibility of using a clinical MR scanner to study striatal graft development in a rat model of Huntington's disease. Rat fetal lateral ganglionic...... eminences grown as free-floating roller-tube cultures can be successfully grafted in a rat Huntington model and that a clinical MR scanner offers a useful noninvasive tool for studying striatal graft development....

  17. Radiation grafting of dimethylaminopropylacrylamide and dimethylaminopropylmethacrylamide onto polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Burillo, Guillermina; Oseguera, M.A. [UNAM, Inst. de Ciencias Nucleares, Mexico City (Mexico); Vazquez, Carmen; Castillo, L.P. del [UNAM, Inst. de Investigaciones en Materiales, Mexico City (Mexico)

    1997-11-01

    Radiation-induced grafting of dimethylaminopropylacrylamide and dimethylamino-propylmethacrylamide onto polyethylene films, by direct grafting of the vinyl monomers to a polymer by mutual irradiation, has been investigated. The kinetics of the reaction were studied at different irradiation temperatures, monomer concentration and dose rates of gamma rays, and the appropriate reaction conditions for graft polymerization were determined. The thermal and mechanical behavior of the grafted films by means of DMA, TMA, DSC and TGA were also investigated. (author).

  18. An experimental study on inhibiting graft rejection following high-risk penetrating keratoplasty by CD25 siRNA nanocarrier in rats

    Directory of Open Access Journals (Sweden)

    Yun-jie SHI

    2015-06-01

    Full Text Available Objective To investigate the effects of CD25 siRNA nanoparticles against immune rejection and prolongation of corneal graft survival time after high-risk corneal grafting in rats. Methods Orthotopic corneal transplantation was performed in SD rats with alkali burned corneas to mimic high-risk rat models. Donor cornea (Wistar rats was grafted into the right cornea of SD recipients on day 14 after alkali burn. The grafted rats were randomly divided into control group (Group A, EntransterTM-control CD25siRNA instillation treatment (Group B, EntransterTM-CD25siRNA instillation treatment (Group C and EntransterTM-CD25siRNA twice instillation treatment (Group D, first administration at 2-hour post-surgery and second on day 7 post-surgery. The recipient eyes were examined using a slit lamp microscope. Then, the mean survival time and rejection index (RI were calculated. The morphologies of grafts were microscopically examined with HE staining, and TEM. CD25 expression after operation was determined by quantitative RT-PCR and immunohistochemistry. Results The survival curves of transplanted cornea showed that the mean survival time in rats of groups C and D was significantly longer than that in groups A and B (P<0.05. No significant difference was found in survival time between group A and group B, and the same between group C and group D. The grafts in groups A and B showed obvious edema and thickening, with irregular arrangement of collagen fibers and infiltration of a large amount of inflammatory cells. Immunohistochemical results showed that expression of CD25 was found in the corneal epithelium, stroma and endothelium in all rats, and higher CD25 expression was observed in groups A and B. Transmission electron microscopy revealed that the degree of stromal fibroblast apoptosis and necrosis in corneal graft was obviously lower in groups C and D than that of groups A and B, with a significant statistical difference. The expression of CD25 m

  19. Anterior palatal island advancement flap for bone graft coverage ...

    African Journals Online (AJOL)

    ... Palatal Island Advancement Flap was effective in bone graft coverage in premaxillary edentulous area. Conclusion: It can be used as an aid for bone graft coverage of premaxillary edentulous ridge, where the need for mucosa is small in width but long in length. Keywords: Anterior maxilla, bone graft, dental implant, ...

  20. Bone structure changes in iliac crest grafts combined with implants

    NARCIS (Netherlands)

    Verhoeven, Jan Willem; Ruijter, Jan M.; Koole, Ronald; de Putter, Cornelis; Cune, Marco S.

    2010-01-01

    Remodeling of onlay grafts combined with implants to the mandible results in predictable changes in the graft's radiographic density. We studied the relationship between changes in radiographic density and trabecular structure during the first year after onlay grafting with simultaneous implant

  1. Polymer–clay nanocomposites via chemical grafting of ...

    Indian Academy of Sciences (India)

    The radical polymerization of the product with acrylonitrile (AN) as a vinyl monomer leads to chemical grafting of polyacrylonitrile onto montmorillonite surface. The homopolymer formed during polymerization was separated from the grafted organoclay by Soxhlet extraction. Chemical grafting of the polymer onto Cloisite 20A ...

  2. Defense mechanisms involved in disease resistance of grafted vegetables

    Science.gov (United States)

    Vegetable grafting with resistant rootstocks is an effective strategy to control a variety of soil-borne diseases and root-knot nematodes in the Cucurbitaceae and Solanaceae. In addition, improved resistance to some foliar diseases and viruses has also been reported in grafted plants. Hence, graft...

  3. The Influence of Barrier Membranes on Autologous Bone Grafts

    NARCIS (Netherlands)

    Gielkens, P. F. M.; Schortinghuis, J.; de Jong, J. R.; Paans, A. M. J.; Ruben, J. L.; Raghoebar, G. M.; Stegenga, B.; Bos, R. R. M.

    2008-01-01

    In implant dentistry, there is continuing debate regarding whether a barrier membrane should be applied to cover autologous bone grafts in jaw augmentation. A membrane would prevent graft remodeling with resorption and enhance graft incorporation. We hypothesized that membrane coverage does not

  4. Pressure induced graft-co-polymerization of acrylonitrile onto ...

    Indian Academy of Sciences (India)

    WINTEC

    presence of free radical, a hydrogen atom may be ab- stracted from the cellulose by a growing chain ..... centration of monomer radical per unit volume and hence less grafting takes place. Figure 3. SEM of grafted fibre ... optimum molar ratio for the maximum graft yield has been found to be 0⋅250 : 1. It has been observed ...

  5. Buccal Mucosal Graft for Crippled Hypospadias (Experience in 11 ...

    African Journals Online (AJOL)

    Free buccal mucosal on-lay grafts from the inner aspect of the lower lip were taken for three cases of complicated anterior urethral stricture and for six cases of recurrent urethra-cutaneous fistula after previous multiple penile hypospadias repairs. Nine on-lay free grafts were ventrally placed on the penile urethra. The grafts ...

  6. Preserved cardiac function despite marked impairment of cAMP generation.

    Directory of Open Access Journals (Sweden)

    Mei Hua Gao

    Full Text Available So many clinical trials of positive inotropes have failed, that it is now axiomatic that agents that increase cAMP are deleterious to the failing heart. An alternative strategy is to alter myocardial Ca(2+ handling or myofilament response to Ca(2+ using agents that do not affect cAMP. Although left ventricular (LV function is tightly linked to adenylyl cyclase (AC activity, the beneficial effects of AC may be independent of cAMP and instead stem from effects on Ca(2+ handling. Here we ask whether an AC mutant molecule that reduces LV cAMP production would have favorable effects on LV function through its effects on Ca(2+ handling alone.We generated transgenic mice with cardiac-directed expression of an AC6 mutant (AC6mut. Cardiac myocytes showed impaired cAMP production in response to isoproterenol (74% reduction; p<0.001, but LV size and function were normal. Isolated hearts showed preserved LV function in response to isoproterenol stimulation. AC6mut expression was associated with increased sarcoplasmic reticulum Ca(2+ uptake and the EC50 for SERCA2a activation was reduced. Cardiac myocytes isolated from AC6mut mice showed increased amplitude of Ca(2+ transients in response to isoproterenol (p = 0.0001. AC6mut expression also was associated with increased expression of LV S100A1 (p = 0.03 and reduced expression of phospholamban protein (p = 0.01.LV AC mutant expression is associated with normal cardiac function despite impaired cAMP generation. The mechanism appears to be through effects on Ca(2+ handling - effects that occur despite diminished cAMP.

  7. Biochemical characterization and cellular imaging of a novel, membrane permeable fluorescent cAMP analog

    Directory of Open Access Journals (Sweden)

    Zaccolo Manuela

    2008-06-01

    Full Text Available Abstract Background A novel fluorescent cAMP analog (8-[Pharos-575]- adenosine-3', 5'-cyclic monophosphate was characterized with respect to its spectral properties, its ability to bind to and activate three main isoenzymes of the cAMP-dependent protein kinase (PKA-Iα, PKA-IIα, PKA-IIβ in vitro, its stability towards phosphodiesterase and its ability to permeate into cultured eukaryotic cells using resonance energy transfer based indicators, and conventional fluorescence imaging. Results The Pharos fluorophore is characterized by a Stokes shift of 42 nm with an absorption maximum at 575 nm and the emission peaking at 617 nm. The quantum yield is 30%. Incubation of the compound to RIIα and RIIβ subunits increases the amplitude of excitation and absorption maxima significantly; no major change was observed with RIα. In vitro binding of the compound to RIα subunit and activation of the PKA-Iα holoenzyme was essentially equivalent to cAMP; RII subunits bound the fluorescent analog up to ten times less efficiently, resulting in about two times reduced apparent activation constants of the holoenzymes compared to cAMP. The cellular uptake of the fluorescent analog was investigated by cAMP indicators. It was estimated that about 7 μM of the fluorescent cAMP analog is available to the indicator after one hour of incubation and that about 600 μM of the compound had to be added to intact cells to half-maximally dissociate a PKA type IIα sensor. Conclusion The novel analog combines good membrane permeability- comparable to 8-Br-cAMP – with superior spectral properties of a modern, red-shifted fluorophore. GFP-tagged regulatory subunits of PKA and the analog co-localized. Furthermore, it is a potent, PDE-resistant activator of PKA-I and -II, suitable for in vitro applications and spatial distribution evaluations in living cells.

  8. Photosensitized electron transfer within a self-assembled norharmane-2'-deoxyadenosine 5'-monophosphate (dAMP) complex.

    Science.gov (United States)

    Gonzalez, M Micaela; Rasse-Suriani, Federico A O; Franca, Carlos A; Diez, Reinaldo Pis; Gholipour, Yousef; Nonami, Hiroshi; Erra-Balsells, Rosa; Cabrerizo, Franco M

    2012-12-21

    Norharmane is a compound that belongs to a family of alkaloids called β-carbolines (βCs). These alkaloids are present in a wide range of biological systems, playing a variety of significant photo-dependent roles. Upon UV-A irradiation, βCs are able to act as efficient photosensitizers. In this work, we have investigated the photosensitized oxidation of 2'-deoxyadenosine 5'-monophosphate (dAMP) by norharmane in an aqueous phase, upon UV-A (350 nm) irradiation. The effect of the pH was evaluated on both the interactions between norharmane and dAMP in the ground and electronic excited states, and on the dAMP photosensitized oxidation. A quite strong static interaction between norharmane and dAMP was observed, especially under those pH conditions where the protonated form of the alkaloid is present (pH dAMP complex is the operative mechanism in the dAMP photosensitization.

  9. Aortic Graft Infection: Graphene Shows the Way to an Infection-Resistant Vascular Graft

    Directory of Open Access Journals (Sweden)

    Nikolaos Patelis

    2017-05-01

    Full Text Available Aortic graft infection is a potentially lethal complication of open and endovascular repair of aortic aneurysms. Graphene is the only existing two-dimensional material, and its unique structure gives graphene and its derivatives a plethora of original characteristics. Among other characteristics, graphene demonstrates bacteriostatic and bactericidal effects that could potentially resolve the problem of graft infection in the future. Data already exist in literature supporting this antibacterial effect of graphene oxide and reduced graphene oxide. Combining these materials with other substances enhances the antibacterial effect. Additionally, it looks feasible to expect antibiotic-delivering graphene-based graft materials in the future. Based on already published data, we could conclude that regarding graphene and its derivatives, the blessing of bactericidal effect comes with the curse of human cells toxicity. Therefore, it is important to find a fine balance between the desired antibacterial and the adverse cytotoxic effect before graphene is used in graft materials for humans.

  10. Epidermal grafting versus split-thickness skin grafting for wound healing (EPIGRAAFT): study protocol for a randomised controlled trial

    OpenAIRE

    Kanapathy, Muholan; Hachach-Haram, Nadine; Bystrzonowski, Nicola; Harding, Keith; Mosahebi, Afshin; Richards, Toby

    2016-01-01

    Background Split-thickness skin grafting (SSG) is an important modality for wound closure. However, the donor site becomes a second, often painful wound, which may take more time to heal than the graft site itself and holds the risk of infection and scarring. Epidermal grafting (EG) is an alternative method of autologous skin grafting that harvests only the epidermal layer of the skin by applying continuous negative pressure on the normal skin to raise blisters. This procedure has minimal don...

  11. Mechanisms of cyclic nucleotide phosphodiesterases in modulating T cell responses in murine graft-versus-host disease.

    Directory of Open Access Journals (Sweden)

    Michael Weber

    Full Text Available Graft-versus-host disease (GvHD is a key contributor to the morbidity and mortality after allogeneic hematopoetic stem cell transplantation (HSCT. Regulatory Foxp3(+ CD4(+ T cells (Treg suppress conventional T cell activation and can control GvHD. In our previous work, we demonstrate that a basic mechanism of Treg mediated suppression occurs by the transfer of cyclic adenosine monophosphate (cAMP to responder cells. Whether this mechanism is relevant for Treg mediated suppression of GvHD is currently unknown. To address this question, bone marrow and T cells from C57BL/6 mice were transferred into lethally irradiated BALB/c recipients, and the course of GvHD and survival were monitored. Transplanted recipients developed severe GvHD that was strongly ameliorated by the transfer of donor Treg cells. Towards the underlying mechanisms, in vitro studies revealed that Treg communicated with DCs via gap junctions, resulting in functional inactivation of DC by a metabolic pathway involving cAMP that is modulated by the phosphodiesterase (PDE 4 inhibitor rolipram. PDE2 or PDE3 inhibitors as well as rolipram suppressed allogeneic T cell activation, indirectly by enhancing Treg mediated suppression of DC activation and directly by inhibiting responder T cell proliferation. In line with this, we observed a cooperative suppression of GvHD upon Treg transfer and additional rolipram treatment. In conclusion, we propose that an important pathway of Treg mediated control of GvHD is based on a cAMP dependent mechanism. These data provide the basis for future concepts to manipulate allogeneic T cell responses to prevent GvHD.

  12. Grafting functional antioxidants on highly crosslinked polyethylene

    Science.gov (United States)

    Al-Malaika, S.; Riasat, S.; Lewucha, C.

    2016-05-01

    The problem of interference of antioxidants, such as hindered phenols, with peroxide-initiated crosslinking of polyethylene was addressed through the use of functional (reactive) graftable antioxidants (g-AO). Reactive derivatives of hindered phenol and hindered amine antioxidants were synthesised, characterised and used to investigate their grafting reactions in high density polyethylene; both non-crosslinked (PE) and highly peroxide-crosslinked (PEXa). Assessment of the extent of in-situ grafting of the antioxidants, their retention after exhaustive solvent extraction in PE and PEXa, and the stabilising performance of the grafted antioxidants (g-AO) in the polymer were examined and benchmarked against conventionally stabilised crosslinked & non-crosslinked polyethylene. It was shown that the functional antioxidants graft to a high extent in PEXa, and that the level of interference of the g-AOs with the polymer crosslinking process was minimal compared to that of conventional antioxidants which bear the same antioxidant function. The much higher level of retention of the g-AOs in PEXa after exhaustive solvent extraction, compared to that of the corresponding conventional antioxidants, accounts for their superior long-term thermal stabilising performance under severe extractive conditions.

  13. Bud-grafting yellow-poplar

    Science.gov (United States)

    David T. Funk

    1963-01-01

    Several years ago we began work on the vegetative propagation of yellow-poplar (Liriodendron tulipifera L.) with the aim of eventually establishing a clonal seed orchard. We tried field grafting, field budding, and air layering. We then attempted rooting cuttings in the greenhouse and in an indoor propagation bench. The best we could do with any of these methods was 4...

  14. Synthesis and properties of carboxymethylcellulose (CMC) graft ...

    African Journals Online (AJOL)

    Novel biopolymer-based superabsorbent hydrogels were prepared by grafting crosslinked poly (N-vinyl pyrollidin and 2-Acrylamido-2-methyl propan sulfonic acid (PNVP-co-PAMPS) chains onto CMC backbones through a free radical polymerization method. A proposed mechanism for superabsorbent hydrogel formation ...

  15. Fatal Saccharomyces Cerevisiae Aortic Graft Infection

    Science.gov (United States)

    Meyer, Michael (Technical Monitor); Smith, Davey; Metzgar, David; Wills, Christopher; Fierer, Joshua

    2002-01-01

    Saccharomyces cerevisiae is a yeast commonly used in baking and a frequent colonizer of human mucosal surfaces. It is considered relatively nonpathogenic in immunocompetent adults. We present a case of S. cerevisiae fungemia and aortic graft infection in an immunocompetent adult. This is the first reported case of S. cerevisiue fungemia where the identity of the pathogen was confirmed by rRNA sequencing.

  16. Dynamics of solvent-free grafted nanoparticles

    KAUST Repository

    Chremos, Alexandros

    2012-01-01

    The diffusivity and structural relaxation characteristics of oligomer-grafted nanoparticles have been investigated with simulations of a previously proposed coarse-grained model at atmospheric pressure. Solvent-free, polymer-grafted nanoparticles as well as grafted nanoparticles in a melt were compared to a reference system of bare (ungrafted) particles in a melt. Whereas longer chains lead to a larger hydrodynamic radius and lower relative diffusivity for grafted particles in a melt, bulk solvent-free nanoparticles with longer chains have higher relative diffusivities than their short chain counterparts. Solvent-free nanoparticles with short chains undergo a glass transition as indicated by a vanishing diffusivity, diverging structural relaxation time and the formation of body-centered-cubic-like order. Nanoparticles with longer chains exhibit a more gradual increase in the structural relaxation time with decreasing temperature and concomitantly increasing particle volume fraction. The diffusivity of the long chain nanoparticles exhibits a minimum at an intermediate temperature and volume fraction where the polymer brushes of neighboring particles overlap, but must stretch to fill the interparticle space. © 2012 American Institute of Physics.

  17. Surface modification of cellulose by PCL grafts

    International Nuclear Information System (INIS)

    Paquet, Olivier; Krouit, Mohammed; Bras, Julien; Thielemans, Wim; Belgacem, Mohamed Naceur

    2010-01-01

    Two cellulosic substrates (microcrystalline cellulose, MCC, and bleached kraft softwood pulps, BSK) were grafted by polycaprolactone (PCL) chains with different molecular weights, following a three-step procedure using non-swelling conditions in order to limit the reaction to their surface. First, one of the two OH PCL ends was blocked by phenyl isocyanate and the reaction product (adduct 1) was subsequently reacted with 2,4-toluene diisocyanate (adduct 2) to provide it with an NCO function, capable of reacting with cellulose. The ensuing PCL-grafted cellulosic materials were characterized by weight gain, elemental analysis, contact angle measurements, attenuated total reflexion-Fourier transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and biodegradation tests. The modification was proven to occur by the presence of nitrogen atoms in the elemental analysis tests and XPS spectra of modified and soxhlet-extracted cellulose. The contact angle measurements have also shown that the surface became as hydrophobic as PCL itself. The polar component of the surface energy of cellulosic substrates before treatment was found to be about 32 and 10 mJ m -2 , for MCC and BSK, respectively. This value vanished to practically zero after grafting with different PCLs. The strategy proposed in the present work is original since, to the best of our knowledge, this paper reports for the first time the chemical 'grafting onto' of the cellulose surface by PCL macromolecular structures, with the aim of obtaining fibre-matrix co-continuous fully sustainable and biodegradable composite materials.

  18. Cellular grafts in management of leucoderma

    Directory of Open Access Journals (Sweden)

    Mysore Venkataram

    2009-01-01

    Full Text Available Cellular grafting methods constitute important advances in the surgical management of leucoderma. Different methods such as noncultured epidermal suspensions, melanocyte cultures, and melanocyte-keratinocyte cultures have all been shown to be effective. This article reviews these methods.

  19. Graft Copolymerization and Characterization of Styrene with ...

    African Journals Online (AJOL)

    MBI

    2017-05-24

    May 24, 2017 ... (TGA) revealed that the thermal stability of the prepared copolymer is higher than that of chitosan alone. Mw and Mn of the isolated polystyrene from the graft copolymer were found to ... bis-acrylamide was used as the crosslinking agent, leading to the manufacturer of a materials with desirable mechanical ...

  20. BKV-infection in kidney graft dysfunction

    Directory of Open Access Journals (Sweden)

    Juliana Montagner

    Full Text Available INTRODUCTION: BKV nephropathy (BKN causes kidney graft loss, whose specific diagnosis is invasive and might be predicted by the early detection of active viral infection. OBJECTIVE: Determine the BKV-infection prevalence in late kidney graft dysfunction by urinary decoy cell (DC and viral DNA detection in urine (viruria and blood (viremia; active infection. METHODS: Kidney recipients with >1 month follow-up and creatinine >1.5 mg/dL and/or recent increasing >20% (n = 120 had their urine and blood tested for BKV by semi-nested PCR, DC searching, and graft biopsy. PCR-positive patients were classified as 1+, 2+, 3+. DC, viruria and viremia prevalence, sensitivity, specificity, and likelihood ratio (LR were determined (Table 2x2. Diagnosis efficacy of DC and viruria were compared to viremia. RESULTS: DC prevalence was 25%, viruria 61.7%, and viremia 42.5%. Positive and negative patients in each test had similar clinical, immunossupressive, and histopathological characteristics. There was no case of viremia with chronic allograft nephropathy and, under treatment with sirolimus, patients had a lower viruria prevalence (p = 0.043. Intense viruria was the single predictive test for active infection (3+; LR = 2.8.1,6-4,9 CONCLUSION: DC, BKV-viruria and -viremia are commun findings under late kidney graft dysfunction. Viremia could only be predicted by intense viruria. These results should be considered under the context of BKN confirmation.

  1. Impact of bone graft harvesting techniques on bone formation and graft resorption

    DEFF Research Database (Denmark)

    Saulacic, Nikola; Bosshardt, Dieter D; Jensen, Simon S

    2015-01-01

    in the mandibles of 12 minipigs. The animals were sacrificed after 1, 2, 4 and 8 weeks of healing. Histology and histomorphometrical analyses were performed to assess bone formation and graft resorption. An explorative statistical analysis was performed. RESULTS: The amount of new bone increased, while the amount......: Transplantation of autogenous bone particles harvested with four techniques in the present model resulted in moderate differences in terms of bone formation and graft resorption....

  2. FRET biosensor uncovers cAMP nano-domains at ?-adrenergic targets that dictate precise tuning of cardiac contractility

    OpenAIRE

    Surdo, Nicoletta C.; Berrera, Marco; Koschinski, Andreas; Brescia, Marcella; Machado, Matias R.; Carr, Carolyn; Wright, Peter; Gorelik, Julia; Morotti, Stefano; Grandi, Eleonora; Bers, Donald M.; Pantano, Sergio; Zaccolo, Manuela

    2017-01-01

    Compartmentalized cAMP/PKA signalling is now recognized as important for physiology and pathophysiology, yet a detailed understanding of the properties, regulation and function of local cAMP/PKA signals is lacking. Here we present a fluorescence resonance energy transfer (FRET)-based sensor, CUTie, which detects compartmentalized cAMP with unprecedented accuracy. CUTie, targeted to specific multiprotein complexes at discrete plasmalemmal, sarcoplasmic reticular and myofilament sites, reveals ...

  3. Effect of Grafting Method, Graft Cover and Foliar Spray of some Mineral Elements on Persian Walnut Graft-take and Winter Survival Rate

    Directory of Open Access Journals (Sweden)

    Reza Rezaee

    2017-02-01

    Full Text Available Introduction: Persian walnut (Juglans regia L. is an important nut crop in Iran and many parts of the world. One of the major challenges of growing walnut is planting of non-grafted walnut trees in orchards, which leads to the reduction of yield, quality and productivity of walnut orchards. Compared to the other fruit trees, walnut grafting is difficult and even newly grafted walnut seedlings are vulnerable to fall or winter frost chilling, so that most of the seedlings are lost after subjecting to the cold winter. There are a few studies reporting successful grafting in outdoor conditions, however, final grafting take after winter has been usually ignored. Hence, increased walnut grafting success and improved tree growth after grafting through foliar nutrient application may lead to increased tolerance of chilling. Therefore, main goals of this research were to investigate the effect of some graft covers and role of foliar spray of calcium, boron and zinc on the reduction of frost damage in newly grafted seedlings under outdoor conditions. Materials and methods: This research was conducted at agricultural research station, Khoy city, west Azerbaijan province, during 2012-2014. In the first experiment, three methods of grafting including cleft, bark and V-shaped, and two kinds of graft covers including moist sawdust and superabsorbent plus cotton wool were investigated in terms of grafting success and quality of seedlings. In the second experiment, effect of the three above-mentioned grafting methods and two levels of foliar spray including sequential spray of Ca (4 ppm, B and Zn (2% (3 times during growth season and control (no spray were studied in terms of frost damage. The experiments conducted in factorial based on randomized complete block design with 10 trees in each plot. Data were collected 45 days after grafting take, final grafting take after one winter, subsequent scion growth length and diameter and concentration of Ca, B and Zn in

  4. Grafting of methacryl amide onto γ-irradiated silk fiber and several physical properties of the grafted-silk

    International Nuclear Information System (INIS)

    Tsukada, Masuhio; Aoki, Akira

    1985-01-01

    Strength-strain measurement and DSC were carried out in order to analyze the physical properties of Methacryl amide (MAA)-grafted silk fibers, which had been degummed and irradiated with gamma rays (total dose of gamma rays 1.05 Mrad) prior to the MAA graft processing. Strength, elongation, initile tensile resistance and tensile elasticity of MAA-grafted silk fibers were very similar to those of untreated silk fibers. The degree of grafting for MAA-grafted silk was about 40-42 % regardless of gamma irradiation treatment, while the denier of grafted silk was about 30 % greater than that of untreated silk fiber. Water content and humidity absorption power of the silk fiber markedly increased by the MAA grafting. However, strength and elongation of MAA-grafted silk fiber decreased appeciably compared with the untreated silk fiber. Initial tensile resistance and tensile elasticity of MAA-grafted silk fiber remained uncharged even after MAA grafting. Tensile elasticity of MAA-grafted silk fiber which had been irradiated with gamma rays and successively degummed slightly increased with the other MAA-grafted silk fibers. (author)

  5. Synthesis of Polymer Grafted Magnetite Nanoparticle with the Highest Grafting Density via Controlled Radical Polymerization

    Directory of Open Access Journals (Sweden)

    Babu Kothandapani

    2009-01-01

    Full Text Available Abstract The surface-initiated ATRP of benzyl methacrylate, methyl methacrylate, and styrene from magnetite nanoparticle is investigated, without the use of sacrificial (free initiator in solution. It is observed that the grafting density obtained is related to the polymerization kinetics, being higher for faster polymerizing monomer. The grafting density was found to be nearly 2 chains/nm2for the rapidly polymerizing benzyl methacrylate. In contrast, for the less rapidly polymerizing styrene, the grafting density was found to be nearly 0.7 chain/nm2. It is hypothesized that this could be due to the relative rates of surface-initiated polymerization versus conformational mobility of polymer chains anchored by one end to the surface. An amphiphilic diblock polymer based on 2-hydroxylethyl methacrylate is synthesized from the polystyrene monolayer. The homopolymer and block copolymer grafted MNs form stable dispersions in various solvents. In order to evaluate molecular weight of the polymer that was grafted on to the surface of the nanoparticles, it was degrafted suitably and subjected to gel permeation chromatography analysis. Thermogravimetric analysis, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to confirm the grafting reaction.

  6. ATRP grafting from cellulose fibers to create block-copolymer grafts.

    Science.gov (United States)

    Carlmark, Anna; Malmström, Eva E

    2003-01-01

    Cellulose fibers, in the form of a conventional filter paper, have been modified by reacting the hydroxyl groups on the fiber surface with 2-bromoisobutyryl bromide, followed by grafting using ATRP conditions. The papers were first grafted with methyl acrylate (MA), rendering the paper very hydrophobic as reported in an earlier work. The papers were analyzed by gravimetry, FT-IR, ESCA, and AFM. To verify that the polymerization from the surface was "living", a second layer of another, hydrophilic, polymer, 2-hydroxyethyl methacrylate (HEMA), was grafted upon the PMA layer, creating a block-copolymer graft from the fibers. After the layer of PHEMA had been attached, contact angle measurements were no longer possible, because of the absorbing nature of PHEMA-grafted layer. This indicates that a copolymer had indeed been formed on the surface. FT-IR showed a large increase in carbonyl content after the PHEMA-grafting, which further proves that a layer of PHEMA was attached to the PMA layer. This goes to show that the hydrophilic/hydrophobic behavior of a cellulose surface can be tailored by the use of "living"/controlled radical polymerization methods such as ATRP.

  7. Soft tissue grafting to improve implant esthetics

    Directory of Open Access Journals (Sweden)

    Moawia M Kassab

    2010-09-01

    Full Text Available Moawia M KassabDivision of Periodontics, Marquette University, School of Dentistry, Milwaukee, WI, USAAbstract: Dental implants are becoming the treatment of choice to replace missing teeth, especially if the adjacent teeth are free of restorations. When minimal bone width is present, implant placement becomes a challenge and often resulting in recession and dehiscence around the implant that leads to subsequent gingival recession. To correct such defect, the author turned to soft tissue autografting and allografting to correct a buccal dehiscence around tooth #24 after a malpositioned implant placed by a different surgeon. A 25-year-old woman presented with the chief complaint of gingival recession and exposure of implant threads around tooth #24. The patient received three soft tissue grafting procedures to augment the gingival tissue. The first surgery included a connective tissue graft to increase the width of the keratinized gingival tissue. The second surgery included the use of autografting (connective tissue graft to coronally position the soft tissue and achieve implant coverage. The third and final surgery included the use of allografting material Alloderm to increase and mask the implant from showing through the gingiva. Healing period was uneventful for the patient. After three surgical procedures, it appears that soft tissue grafting has increased the width and height of the gingiva surrounding the implant. The accomplished thickness of gingival tissue appeared to mask the showing of implant threads through the gingival tissue and allowed for achieving the desired esthetic that the patient desired. The aim of the study is to present a clinical case with soft tissue grafting procedures.Keywords: case report, connective tissue, dental implants, allograft, coronally positioned flap

  8. The Cyclic AMP-Vfr Signaling Pathway in Pseudomonas aeruginosa Is Inhibited by Cyclic Di-GMP

    DEFF Research Database (Denmark)

    Almblad, Henrik; Harrison, Joe J; Rybtke, Morten

    2015-01-01

    : Our work suggests that cross talk between c-di-GMP and cAMP signaling pathways results in downregulation of acute virulence factors in P. aeruginosa biofilm infections. Knowledge about this cross-regulation adds to our understanding of virulence traits and immune evasion by P. aeruginosa in chronic......AMP), which is decreased in response to a high level of c-di-GMP. Mutations that cause reversion of the RSCV phenotype concomitantly reactivate Vfr-cAMP signaling. Attempts to uncover the mechanism underlying the observed c-di-GMP-mediated lowering of cAMP content provided evidence that it is not caused...

  9. Effect of cholera toxin on cAMP levels and Na/sup +/ influx in isolated intestinal epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, C.S.; Kimmich, G.A.

    1982-09-01

    Freshly isolated chicken intestinal cells contain approximately 20 pmol adenosine 3',5'-cyclic monophosphate (cAMP)/mg cellular protein. Incubation with 3 ..mu..g/ml cholera toxin (CT) at 37/sup 0/C induces an elevation of cellular cAMP beginning 10-15 min after initial exposure. The response is linear with time for 40-50 min and causes a six- to eightfold increase over control levels at steady state. Dibutyryl cAMP and agents that increase cAMP production inhibit Na/sup +/ influx into the isolated enterocytes. Chlorpromazine completely abolishes the toxin-induced elevation of cAMP in the isolated cells and also reverses the effect on Na/sup +/ entry. The data provide evidence for a cAMP-mediated control of intestinal cell Na/sup +/ uptake, which may represent the mechanistic basis for the antiabsorptive effect of CT on Na/sup +/ during induction of intestinal secretory activity. Studies on the time-dependent effects of chlorpromazine on both intracellular cAMP concentration and Na/sup +/ influx suggest that the reactivation of the Na/sup +/ transport system after cAMP-induced inhibition is slow relative to the disappearance of cAMP.

  10. Different cAMP sources are critically involved in G protein?coupled receptor CRHR1 signaling

    OpenAIRE

    Inda, Carolina; dos Santos Claro, Paula A.; Bonfiglio, Juan J.; Senin, Sergio A.; Maccarrone, Giuseppina; Turck, Christoph W.; Silberstein, Susana

    2016-01-01

    Corticotropin-releasing hormone receptor 1 (CRHR1) activates G protein-dependent and internalization-dependent signaling mechanisms. Here, we report that the cyclic AMP (cAMP) response of CRHR1 in physiologically relevant scenarios engages separate cAMP sources, involving the atypical soluble adenylyl cyclase (sAC) in addition to transmembrane adenylyl cyclases (tmACs). cAMP produced by tmACs and sAC is required for the acute phase of extracellular signal regulated kinase 1/2 activation trigg...

  11. Effect of cholera toxin on cAMP levels and Na+ influx in isolated intestinal epithelial cells

    International Nuclear Information System (INIS)

    Hyun, C.S.; Kimmich, G.A.

    1982-01-01

    Freshly isolated chicken intestinal cells contain approximately 20 pmol adenosine 3',5'-cyclic monophosphate (cAMP)/mg cellular protein. Incubation with 3 μg/ml cholera toxin (CT) at 37 0 C induces an elevation of cellular cAMP beginning 10-15 min after initial exposure. The response is linear with time for 40-50 min and causes a six- to eightfold increase over control levels at steady state. Dibutyryl cAMP and agents that increase cAMP production inhibit Na + influx into the isolated enterocytes. Chlorpromazine completely abolishes the toxin-induced elevation of cAMP in the isolated cells and also reverses the effect on Na + entry. The data provide evidence for a cAMP-mediated control of intestinal cell Na + uptake, which may represent the mechanistic basis for the antiabsorptive effect of CT on Na + during induction of intestinal secretory activity. Studies on the time-dependent effects of chlorpromazine on both intracellular cAMP concentration and Na + influx suggest that the reactivation of the Na + transport system after cAMP-induced inhibition is slow relative to the disappearance of cAMP

  12. Adenylate Kinase and AMP Signaling Networks: Metabolic Monitoring, Signal Communication and Body Energy Sensing

    Directory of Open Access Journals (Sweden)

    Andre Terzic

    2009-04-01

    Full Text Available Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7 are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.

  13. Rac1 controls Schwann cell myelination through cAMP and NF2/merlin

    Science.gov (United States)

    Guo, Li; Moon, Chandra; Niehaus, Karen; Zheng, Yi; Ratner, Nancy

    2013-01-01

    During peripheral nervous system development, Schwann cells (SCs) surrounding single large axons differentiate into myelinating SCs. Previous studies implicate RhoGTPases in SC myelination, but the mechanisms involved in RhoGTPase regulation of SC myelination are unknown. Here, we show that SC myelination is arrested in Rac1 conditional knockout (Rac1-CKO) mice. Rac1 knockout abrogated phosphorylation of the effector p21-activated kinase (PAK) and decreased NF2/merlin phosphorylation. Mutation of NF2/merlin rescued the myelin deficit in Rac1-CKO mice in vivo, and the shortened processes in cultured Rac1-CKO SCs in vitro. Mechanistically, cyclic adenosine monophosphate (cAMP) levels and E-cadherin expression were decreased in the absence of Rac1, and both were restored by mutation of NF2/merlin. Reduced cAMP is a cause of the myelin deficiency in Rac1-CKO mice, as elevation of cAMP by rolipram in Rac1-CKO mice in vivo allowed myelin formation. Thus NF2/merlin and cAMP function downstream of Rac1 signaling in SC myelination, and cAMP levels control Rac1-regulated SC myelination. PMID:23197717

  14. AMP and adenosine are both ligands for adenosine 2B receptor signaling.

    Science.gov (United States)

    Holien, Jessica K; Seibt, Benjamin; Roberts, Veena; Salvaris, Evelyn; Parker, Michael W; Cowan, Peter J; Dwyer, Karen M

    2018-01-15

    Adenosine is considered the canonical ligand for the adenosine 2B receptor (A 2B R). A 2B R is upregulated following kidney ischemia augmenting post ischemic blood flow and limiting tubular injury. In this context the beneficial effect of A 2B R signaling has been attributed to an increase in the pericellular concentration of adenosine. However, following renal ischemia both kidney adenosine monophosphate (AMP) and adenosine levels are substantially increased. Using computational modeling and calcium mobilization assays, we investigated whether AMP could also be a ligand for A 2B R. The computational modeling suggested that AMP interacts with more favorable energy to A 2B R compared with adenosine. Furthermore, AMPαS, a non-hydrolyzable form of AMP, increased calcium uptake by Chinese hamster ovary (CHO) cells expressing the human A 2B R, indicating preferential signaling via the G q pathway. Therefore, a putative AMP-A 2B R interaction is supported by the computational modeling data and the biological results suggest this interaction involves preferential G q activation. These data provide further insights into the role of purinergic signaling in the pathophysiology of renal IRI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Differential regulation by AMP and ADP of AMPK complexes containing different γ subunit isoforms

    DEFF Research Database (Denmark)

    Ross, Fiona A; Jensen, Thomas Elbenhardt; Hardie, D Grahame

    2016-01-01

    The g subunits of heterotrimeric AMPK complexes contain the binding sites for the regulatory adenine nucleotides AMP, ADP and ATP. We addressed whether complexes containing different g isoforms display different responses to adenine nucleotides by generating cells stably expressing FLAG-tagged ve......The g subunits of heterotrimeric AMPK complexes contain the binding sites for the regulatory adenine nucleotides AMP, ADP and ATP. We addressed whether complexes containing different g isoforms display different responses to adenine nucleotides by generating cells stably expressing FLAG......-tagged versions of the g1, g2 or g3 isoform. When assayed at a physiological ATP concentration (5 mM), g1- and g2-containing complexes were allosterically activated almost 10-fold by AMP, with EC50 values one to two orders of magnitude lower than the ATP concentration. By contrast, g3 complexes were barely...... activated by AMP under these conditions, although we did observe some activation at lower ATP concentrations. Despite this, all three complexes were activated, due to increased Thr172 phosphorylation, when cells were incubated with mitochondrial inhibitors that increase cellular AMP. With g1 complexes...

  16. Neurological basis of AMP-dependent thermoregulation and its relevance to central and peripheral hyperthermia

    Science.gov (United States)

    Muzzi, Mirko; Blasi, Francesco; Masi, Alessio; Coppi, Elisabetta; Traini, Chiara; Felici, Roberta; Pittelli, Maria; Cavone, Leonardo; Pugliese, Anna Maria; Moroni, Flavio; Chiarugi, Alberto

    2013-01-01

    Therapeutic hypothermia is of relevance to treatment of increased body temperature and brain injury, but drugs inducing selective, rapid, and safe cooling in humans are not available. Here, we show that injections of adenosine 5′-monophosphate (AMP), an endogenous nucleotide, promptly triggers hypothermia in mice by directly activating adenosine A1 receptors (A1R) within the preoptic area (POA) of the hypothalamus. Inhibition of constitutive degradation of brain extracellular AMP by targeting ecto 5′-nucleotidase, also suffices to prompt hypothermia in rodents. Accordingly, sensitivity of mice and rats to the hypothermic effect of AMP is inversely related to their hypothalamic 5′-nucleotidase activity. Single-cell electrophysiological recording indicates that AMP reduces spontaneous firing activity of temperature-insensitive neurons of the mouse POA, thereby retuning the hypothalamic thermoregulatory set point towards lower temperatures. Adenosine 5′-monophosphate also suppresses prostaglandin E2-induced fever in mice, having no effects on peripheral hyperthermia triggered by dioxymetamphetamine (ecstasy) overdose. Together, data disclose the role of AMP, 5′-nucleotidase, and A1R in hypothalamic thermoregulation, as well and their therapeutic relevance to treatment of febrile illness. PMID:23093068

  17. Pseudomonas aeruginosa AmpR: an acute–chronic switch regulator

    Science.gov (United States)

    Balasubramanian, Deepak; Kumari, Hansi; Mathee, Kalai

    2015-01-01

    Pseudomonas aeruginosa is one of the most intractable human pathogens that pose serious clinical challenge due to extensive prevalence of multidrug-resistant clinical isolates. Armed with abundant virulence and antibiotic resistance mechanisms, it is a major etiologic agent in a number of acute and chronic infections. A complex and intricate network of regulators dictates the expression of pathogenicity factors in P. aeruginosa. Some proteins within the network play key roles and control multiple pathways. This review discusses the role of one such protein, AmpR, which was initially recognized for its role in antibiotic resistance by regulating AmpC β-lactamase. Recent genomic, proteomic and phenotypic analyses demonstrate that AmpR regulates expression of hundreds of genes that are involved in diverse pathways such as β-lactam and non-β-lactam resistance, quorum sensing and associated virulence phenotypes, protein phosphorylation, and physiological processes. Finally, ampR mutations in clinical isolates are reviewed to shed light on important residues required for its function in antibiotic resistance. The prevalence and evolutionary implications of AmpR in pathogenic and nonpathogenic proteobacteria are also discussed. A comprehensive understanding of proteins at nodal positions in the P. aeruginosa regulatory network is crucial in understanding, and ultimately targeting, the pathogenic stratagems of this organism. PMID:25066236

  18. Cyclic AMP Pathway Activation and Extracellular Zinc Induce Rapid Intracellular Zinc Mobilization in Candida albicans

    Science.gov (United States)

    Kjellerup, Lasse; Winther, Anne-Marie L.; Wilson, Duncan; Fuglsang, Anja T.

    2018-01-01

    Zinc is an essential micronutrient, required for a range of zinc-dependent enzymes and transcription factors. In mammalian cells, zinc serves as a second messenger molecule. However, a role for zinc in signaling has not yet been established in the fungal kingdom. Here, we used the intracellular zinc reporter, zinbo-5, which allowed visualization of zinc in the endoplasmic reticulum and other components of the internal membrane system in Candida albicans. We provide evidence for a link between cyclic AMP/PKA- and zinc-signaling in this major human fungal pathogen. Glucose stimulation, which triggers a cyclic AMP spike in this fungus resulted in rapid intracellular zinc mobilization and this “zinc flux” could be stimulated with phosphodiesterase inhibitors and blocked via inhibition of adenylate cyclase or PKA. A similar mobilization of intracellular zinc was generated by stimulation of cells with extracellular zinc and this effect could be reversed with the chelator EDTA. However, zinc-induced zinc flux was found to be cyclic AMP independent. In summary, we show that activation of the cyclic AMP/PKA pathway triggers intracellular zinc mobilization in a fungus. To our knowledge, this is the first described link between cyclic AMP signaling and zinc homeostasis in a human fungal pathogen. PMID:29619016

  19. Cesium absorption from acidic solutions using ammonium molybdophosphate on a polyacrylonitrile support (AMP-PAN)

    International Nuclear Information System (INIS)

    Miller, C.J.; Olson, A.L.; Johnson, C.K.

    1995-01-01

    Recent efforts at the Idaho Chemical Processing Plant (ICPP) have included evaluation of cesium removal technologies as applied to ICPP acidic radioactive waste streams. Ammonium molybdophosphate (AMP) immobilized on a polyacrylonitrile support (AMP-PAN) has been studied as an ion exchange agent for cesium removal from acidic waste solutions. Capacities, distribution coefficients, elutability, and kinetics of cesium-extraction have been evaluated. Exchange breakthrough curves using small columns have been determined from 1M HNO 3 and simulated waste solutions. The theoretical capacity of AMP is 213 g Cs/kg AMP. The average experimental capacity in batch contacts with various acidic solutions was 150 g Cs/kg AMP. The measured cesium distribution coefficients from actual waste solutions were 3287 mL/g for dissolved zirconia calcines, and 2679 mL/g for sodium-bearing waste. The cesium in the dissolved alumina calcines was analyzed for; however, the concentration was below analytical detectable limits resulting in inconclusive results. The reaction kinetics are very rapid (2-10 minutes). Cesium absorption appears to be independent of acid concentration over the range tested (0.1 M to 5 M HNO 3 )

  20. Proteomic signatures implicate cAMP in light and temperature responses in Arabidopsis thaliana

    KAUST Repository

    Thomas, Ludivine

    2013-05-01

    The second messenger 3\\'-5\\'-cyclic adenosine monophosphate (cAMP) and adenylyl cyclases (ACs), enzymes that catalyse the formation of cAMP from ATP, are increasingly recognized as important signaling molecules in a number of physiological responses in higher plants. Here we used proteomics to identify cAMP-dependent protein signatures in Arabidopsis thaliana and identify a number of differentially expressed proteins with a role in light- and temperature-dependent responses, notably photosystem II subunit P-1, plasma membrane associated cation-binding protein and chaperonin 60 β. Based on these proteomics results we conclude that, much like in cyanobacteria, algae and fungi, cAMP may have a role in light signaling and the regulation of photosynthesis as well as responses to temperature and we speculate that ACs could act as light and/or temperature sensors in higher plants. Biological significance: This current study is significant since it presents the first proteomic response to cAMP, a novel and key second messenger in plants. It will be relevant to researchers in plant physiology and in particular those with an interest in second messengers and their role in biotic and abiotic stress responses. © 2013 Elsevier B.V.