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Germline Maintenance Through the Multifaceted Activities of GLH/Vasa in caenorhabditis elegans P Granules

GENETIcS 2019年第3期213卷 923-939页

作者： Marnik, Elisabeth A. Fuqua, J. Heath Sharp, catherine S. Rochester, Jesse D. Xu, Emily L. Holbrook, Sarah E. Updike, Dustin L. Mt Desert Isl Biol Lab Bar Harbor ME 04672 USA Coll Atlantic Bar Harbor ME 04609 USA Univ Maine Grad Sch Biomed Sci & Engn Orono ME 04469 USA Coll William & Mary Williamsburg VA 23185 USA Jackson Lab Bar Harbor ME 04609 USA

Vasa homologs are ATP-dependent DEAD-box helicases, multipotency factors, and critical components that specify and protect the germline. They regulate translation, amplify piwi-interacting RNAs (piRNAs), and act as RNA solvents;however, the limited availability of mutagenesis-derived alleles and their wide range of phenotypes have complicated their analysis. Now, with clustered regularly interspaced short palindromic repeats (cRISPR/cas9), these limitations can be mitigated to determine why protein domains have been lost or retained throughout evolution. Here, we define the functional motifs of /Vasa in caenorhabditis elegans using 28 endogenous, mutant alleles. We show that 's helicase activity is required to retain its association with P granules. remains in P granules when changes are made outside of the helicase and flanking domains, but fertility is still compromised. Removal of the glycine-rich repeats from GLH proteins progressively diminishes P-granule wetting-like interactions at the nuclear periphery. Mass spectrometry of -associated proteins implies conservation of a transient piRNA-amplifying complex, and reveals a novel affinity between and three structurally conserved PcI (26S Proteasome Lid, cOP9, and eIF3) complexes or "zomes," along with a reciprocal aversion for assembled ribosomes and the 26S proteasome. These results suggest that P granules compartmentalize the cytoplasm to exclude large protein assemblies, effectively shielding associated transcripts from translation and associated proteins from turnover. Within germ granules, Vasa homologs may act as solvents, ensuring mRNA accessibility by small RNA surveillance and amplification pathways, and facilitating mRNA export through germ granules to initiate translation.

关键词： Vasa GLH-1 DDX4 germ granules P granules c elegans germline PcI complex

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Tuning dependent beam characteristics of continuously tunable laser diodes

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ELEcTRONIcS LETTERS 1999年第13期35卷 1102-1103页

作者： Steffens, WM Nöding, M Illek, S Borchert, J Amann, Mc Univ Kassel Dept Elect Engn D-34132 Kassel Germany Siemens AG Corp Technol D-81730 Munich Germany

The beam characteristic of continuously tunable twin-guide (TTG) laser diodes has been investigated and it was observed that the beam profile is changed during tuning. This affects the coupling of the laser light into a fibre interface, leading to a reduction in transmitted optical power. It is shown how the coupling losses during tuning can be compensated for. An observed shift in the lateral far field has a high potential for the realisation of a continuously beam steering device.

关键词： Semiconductor lasers optical fibre couplers fibre interface optical fibre coupling Laser beam modulation, pulsing and switching compensated continuously tunable laser diodes transmitted optical power reduction laser tuning laser light coupling beam profile waveguide lasers Lasing action in semiconductors continuously tunable twin-guide laser diodes continuously beam steering device laser beams semiconductor lasers c mode locking and tuning beam characteristic coupling losses lateral far field shift tuning dependent beam characteristics Laser beam characteristics and interactions tuning optical losses

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Graphene oxide-based non-volatile organic field effect memory transistors

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IET cIRcUITS DEVIcES & SYSTEMS 2015年第1期9卷 67-71页

作者： Alaabdlqader, Homod S. Sleiman, Adam Sayers, Paul Mabrook, Mohammed F. Bangor Univ Sch Elect Engn Bangor LL57 1UT Gwynedd Wales

To produce organic non-volatile organic memory transistors, graphene oxide (GO) nanoparticles were embedded in the floating gate of an all organic memory structure using polymethylmethacrylate as the dielectric and pentacene as the organic semiconductor. The current-voltage characteristics and the memory behaviour of the GO-based organic thin film memory transistors are reported. GO-based memory transistors were shown to produce reliable and large memory windows by virtue of high capacity and reduced charge leakage. The hysteresis in the output and transfer characteristics and shifts in the threshold voltage of the transfer characteristics were attributed to the charging and discharging of the floating gate. Fast switching and large memory windows (approximate to 26 V) exhibiting high charge density (6.25 x 10(12) cm(-2)) were achieved.

关键词： graphene organic field effect transistors random-access storage nanoparticles dielectric materials polymers organic compounds thin film transistors semiconductor device reliability graphene oxide-based non-volatile organic field effect memory transistor GO nanoparticle floating gate dielectric polymethylmethacrylate pentacene organic semiconductor current-voltage characteristics organic thin film memory transistor GO-based memory transistor reliability reduced charge leakage transfer characteristics c

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Ultrastable method for determination of folic acid based on polyneutral red and multiwalled carbon nanotubes composite nanofilm

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MIcRO & NANO LETTERS 2014年第3期9卷 206-209页

作者： Qu, Jianying Du, Xueping Lou, Tongfang Dong, Ying Shi, Lijuan Henan Univ Inst Environm & Analyt Sci Coll Chem & Chem Engn Kaifeng 475004 Henan Peoples R China

By using the electrocatalytic property of the nanomaterials and the molecular recognition characteristic of neutral red (NR), a new modified electrode was fabricated by electropolymerising the NR onto the surface of the multiwalled carbon nanotubes modified glassy carbon electrode, which exhibited a good electrocatalytic activity for folic acid (FA). The results of experiments showed that a good linear relationship between the reductive peak current of FA and its concentration was in the range of 6.25 x 10(-7)-5.00 x 10(-5) mol/l with a detection limit of 1.37 x 10(-7) mol/l in the optimal conditions. The recovery ratio was in the range of 99.3 approximate to 103.2%. The composite film modified electrode exhibited an excellent stability with a simple fabrication, which established a solid foundation for the practical applications.

关键词： carbon nanotubes nanocomposites organic compounds thin films electrochemical electrodes polymerisation catalysis nanofabrication folic acid polyneutral red multiwalled carbon nanotubes composite nanofilm electrocatalytic property nanomaterials molecular recognition characteristics electrode electropolymerisation glassy carbon electrode reductive peak current detection limit c

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caenorhabditis elegans septins contribute to the development and structure of the oogenic germline

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cYTOSKELETON 2023年第7-8期80卷 215-227页

作者： Perry, Jenna A. Werner, Michael E. Rivenbark, Larry Maddox, Amy Shaub Univ North Carolina Chapel Hill Dept Biol Chapel Hill NC USA Univ North Carolina Chapel Hill Dept Biol Chapel Hill NC 27599 USA

Oocytes must be exceptionally large cells in order to support embryonic development. Throughout animal phylogeny, a specialized cell called a syncytium, wherein many nuclei share a continuous cytoplasm, achieves oogenesis. The syncytial nature of germline architecture is key to its function and depends on conserved components of the cortical cytoskeleton. Septins form non-polar cytoskeletal polymers that associate with membranes. In the syncytial germline of the nematode caenorhabditis elegans, septins are highly enriched on the cortex and generally required for fertility, but the role of septins in the germline is poorly understood. We report that the c. elegans septins, UNc-59 and UNc-61, are important for germline extension during development, the maintenance of its syncytial architecture, and production of oocytes. While much of our findings substantiate the idea that the two c. elegans septins act together, we also found evidence that they have distinct functions. Loss of UNc-61 perturbed germline extension during germline development, while the loss of UNc-59 function severely affected germline architecture in adult hermaphrodites. consultation of clustering results from a large-scale high-throughput screen suggested that septins are involved in germ cell proliferation and/or differentiation. In sum, our findings implicate a conserved cytoskeletal component in the complex architecture of a germline syncytium.

关键词： c elegans cell division cytoskeleton oogenesis septins syncytium

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ccAAT/enhancer binding protein is involved in the expression of the tumour necrosis factor gene in human monocytes

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cYTOKINE 1996年第5期8卷 335-341页

作者： Wedel, A Sulski, G ZieglerHeitbrock, HWL UNIV MUNICH INST IMMUNOLD-80336 MUNICHGERMANY

Within the human TNF promoter we have identified two sites at positions -189 and -101 that show c/EBP specific binding of nuclear proteins from cells of the human monocytic line Mono Mac 6. Supershift analysis with anti c/EBP antibodies revealed that the complexes formed consist of both c/EBP alpha and c/EBP beta. When studying reporter constructs with a 5'-deletion series of the TNF promoter in cotransfection experiments,vith a c/EBP beta expression plasmid, a construct with the -1064 TNF fragment gave 26-fold transactivation, the -630 fragment showed 23-fold transactivation and the -107 fragment (containing the -101 c/EBP binding motif) still gave M-fold transactivation. Mutagenesis of the -101 site in the -630 construct resulted in a reduction of c/EBP driven transactivation from 26-fold to 7-fold. Finally, when Mono Mac 6 cells were transfected with these constructs, stimulation by LPS induced a 19-fold transactivation in the -630 wild type construct, while the -630 construct carrying the -101 mutation was transactivated only 4-fold. Hence, the data indicate that the -101 c/EBP motif is crucial for TNF gene expression in human monocytes. (c) 1996 Academic Press Limited

关键词： c EBP monocytes TNF LPS transactivation

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citral and its derivatives inhibit quorum sensing and biofilm formation in chromobacterium violaceum

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ARcHIVES OF MIcROBIOLOGY 2021年第4期203卷 1451-1459页

作者： Batohi, Nikayla Lone, Shabir Ahmad Marimani, Musa Wani, Mohmmad Younus Al-Bogami, Abdullah Saad Ahmad, Aijaz Univ Witwatersrand Sch Pathol Clin Microbiol & Infect Dis Hlth Sci ZA-2193 Johannesburg South Africa Univ Witwatersrand Sch Pathol Anat Pathol Hlth Sci ZA-2193 Johannesburg South Africa Univ Jeddah Dept Chem Coll Sci Jeddah 21589 Saudi Arabia Charlotte Maxeke Johannesburg Acad Hosp Div Infect Control Natl Hlth Lab Serv ZA-2193 Johannesburg South Africa

With an upsurge in multidrug resistant bacteria backed by biofilm defence armours, there is a desperate need of new antibiotics with a non-traditional mechanism of action. Targeting bacteria by misguiding them or halting their communication is a new approach that could offer a new way to combat the multidrug resistance problem. Quorum sensing is considered to be the achilles heel of bacteria that has a lot to offer. Since, both quorum sensing and biofilm formation have been related to drug resistance and pathogenicity, in this study we synthesised new derivatives of citral with antiquorum sensing and biofilm disrupting properties. We previously reported antimicrobial and antiquorum sensing activity of citral and herein we report the synthesis and evaluation of citral and its derivatives (cD1-cD3) for antibacterial, antibiofilm and antiquorum sensing potential against chromobacterium violaceum using standard methods. Preliminary results revealed that cD1 is the most active of all the derivatives. Qualitative and quantitative evaluation of antiquorum sensing activity at sub-inhibitory concentrations of these compounds also revealed high activity for cD1 followed by cD2, cD3 and citral. These compounds also inhibit biofilm formation at subinhibitory concentrations without causing any bacterial growth inhibition. These results were replicated by RT-qPcR with down regulation of the quorum sensing genes when c. violaceum was treated with these test compounds. Overall, the results are quite encouraging, revealing that biofilm and quorum sensing are interrelated processes and also indicating the potential of these derivatives to impede bacterial communication and biofilm formation.

关键词： Quorum sensing Biofilm c violaceum citral

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cHIcKEN EGGSHELL PORPHYRINS AND THE GLYOXALASE PATHWAY - ITS POSSIBLE PHYSIOLOGIcAL-ROLE

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cOMPARATIVE BIOcHEMISTRY AND PHYSIOLOGY B-BIOcHEMISTRY & MOLEcULAR BIOLOGY 1993年第4期104卷 657-662页

作者： VANBRUMMELEN, R BISSBORT, S Department of Chemical Pathology University of Pretoria PO Box 2034 Pretoria 0001 South Africa (Fax 2712 3244886)

1. The plasma 4,5-dioxovaleric acid (DOVA) levels of two different breeds of chicken were determined and found to be higher in the group with a higher porphyrin eggshell content. 2. The erythrocyte and uterus glyoxalase II activity, investigated by means of a new spectrophotometric method, was found to be significantly higher in the group with a low porphyrin eggshell content. 3. A comparative genetic study of two chicken populations, one with white and one with dark eggshells, showed different gene frequencies for the glyoxalase I polymorphism. 4. An interpretation of these data suggests that the glyoxalase pathway may be involved in the metabolism of early porphyrin precursors.

关键词： ALA-synthethase succinyl coA glycine c -succinyl transferase (Ec 2.3.1.37) 5-ALA 5-aminolevulinic acid DOVA 4,5-dioxovaleric acid DOVA-transaminase alanine:dioxovalerate aminotransferase glyoxalase I S -lactoyl-glutathione methylglyoxal-lyase (GLO I, Ec 4.4.1.5) glyoxalase II S -2-hydroxyacyl-glutathione hydrolase (GLO II, Ec 3.1.2.6) DcIP 2,6-dichlorophenolindophenol MTT 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide AIA allylisopropylacetamide

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cYTOTOXIc AND MUTAGENIc EFFEcTS OF ANTI-BENZO[A]PYRENE AND SYN-BENZO[A]PYRENE DIOL EPOXIDE IN HUMAN-LYMPHOcYTES

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TOXIcOLOGY IN VITRO 1994年第6期8卷 1269-1275页

作者： ZANESI, N FERRARO, P PAVANELLO, S FURLAN, D cELOTTI, L UNIV PADUA DEPT BIOLI-35121 PADUAITALY

cytotoxicity and mutagenicity were measured in human lymphocytes after treatment in vitro with anti- or syn-benzo[a]pyrene diolepoxide, two diastereoisomer metabolites of benzo[a]pyrene. These compounds were incubated with resting and cycling lymphocytes to determine the inhibition of cell proliferation induced by phytohemoagglutinin and interleukin2 at different times after treatment. Anti-benzo[a]pyrene diolepoxide was more cytotoxic than the syn-adduct under all conditions, and its effect on cell growth was more marked in cycling lymphocytes. In contrast, neither of the compounds induced alteration of the ATP intracellular pool. cytotoxic effects of anti- and syn-benzo[a]pyrene diolepoxide were also assessed by determining the cloning efficiency. Both compounds affected the cloning efficiency in human lymphocytes and the effect of anti-benzo[a]pyrene was particularly marked. Mutagenic potency of anti- and syn-benzo[a]pyrene diolepoxide at the hgprt locus was measured both in the V79 cell line and in human lymphocytes by selection of mutant cells in medium containing 6-thioguanine. Both compounds increased the mutant frequency in comparison with the control and anti-benzo[a]pyrene diolepoxide was more active than the syn-metabolite.

关键词： BM basic medium B[ a ]P benzo[ a ]pyrene anti-B[ a ]PDE (±)- r -7, t -8-dihydroxy- t -9,10-oxy-7,8,9,10-tetrahydrobenzo[ a ]pyrene syn-B[ a ]PDE (±)- r -7, t -8-dihydroxy- c -9,10-oxy-7,8,9,10-tetrahydrobenzo[ a ]pyrene cE cloning efficiency cHX cycloheximide DMEM Dulbecco's modified Eagle's medium DMSO dimethyl sulfoxide FcS foetal calf serum GM growth medium HBSS Hanks' balanced salt solution HS human serum IL-2 interleukine-2 MF mutant frequency PBL peripheral blood lymphocytes PHA phytohaemagglutinin TcGF T-cell growth factor 6TG 6-thioguanine TPA 12-tetradecanoyl-phorbol 13-acetate

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cost-effectiveness analysis of sodium zirconium cyclosilicate for hyperkalemia among patients with chronic kidney disease or heart failure in Kuwait

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JOURNAL OF MEDIcAL EcONOMIcS 2024年第1期27卷 253-265页

作者： Elsisi, Gihan Hamdy Mahmoud, Mohamed M. Ibrahim Al-Humood, Khaldoon Al-Yousef, Anas HTA Off LLC Cairo Egypt Amer Univ Cairo Hlth Econ Cairo Egypt Jaber Al Ahmed Armed Forces Hosp Dept Med Kuwait Minist Def Kuwait Kuwait Amiri Hosp Head Nephrol Dept Nephrol Dept Kuwait Kuwait Adan Hosp Cardiol Dept MOH Kuwait Kuwait Amer Univ Cairo HTA Off LLC Hlth Econ 51 Helmy Hassan Aly St Cairo Egypt

IntroductionOur model was conducted from Kuwaiti payer's perspective to provide evidence on the cost-effectiveness of Sodium zirconium cyclosilicate (SZc) versus patiromer to correct and maintain serum potassium (K+) in combination with renin-angiotensin-aldosterone system inhibitors (RAASis) with different dose titration in patients with chronic kidney disease/heart failure (cKD/HF) with/without renal replacement therapy (RRT).MethodologyThe model was developed as a patient-level, fixed-time increment stochastic simulation to simulate the complexity of disease, including multiple coexisting and competing conditional risks. This model was established to compare SZc versus patiromer as a treatment for hyperkalemia (HK) among adult populations with underlying conditions of advanced cKD stages 3a-5 or HF to correct and maintain serum K + over a lifetime horizon. The clinical outcomes of SZc and patiromer were demonstrated through arm-specific K + trajectories extracted from the HARMONIZE trial and OPAL-HK trial, respectively. The utility data was captured from different studies. Direct medical cost was captured from local data from Kuwaiti hospitals. Sensitivity analyses were conducted to assess the uncertainty in the *** different scenarios of cKD/HF, SZc was a cost-saving option, with/without RRT, whether one-off administration or repeated administration, except for one-off treatment administration among the HF cohort, which generated an incremental cost effectiveness ratio of KWD 331/quality adjusted life year (QALY). The incremental QALY of SZc ranged from 0.007 to 0.202. In addition, the savings observed with SZc fall within a range of KWD -60 to KWD -1,235 at serum K+ >= 5.1 mmol/*** evidence generated by our model recommends the inclusion of SZc as a treatment option to correct HK and maintain normal serum K + level for cKD/HF patients within the Kuwaiti healthcare system. The costs saved from reducing frequent HK episodes, RAASis dis

关键词： chronic kidney disease heart failure cost-effectiveness analysis sodium zirconium cyclosilicate c52 c5 c E47 E4 E

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