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  • Article
    Chen HC, Hsu CP.
    J Phys Chem A. 2005 Dec 29;109(51):11989-95.
    To calculate electronic couplings for photoinduced electron transfer (ET) reactions, we propose and test the use of ab initio quantum chemistry calculation for excited states with the generalized Mulliken-Hush (GMH) method. Configuration-interaction singles (CIS) is proposed to model the locally excited (LE) and charge-transfer (CT) states. When the CT state couples with other high lying LE states, affecting coupling values, the image charge approximation (ICA), as a simple solvent model, can lower the energy of the CT state and decouple the undesired high-lying local excitations. We found that coupling strength is weakly dependent on many details of the solvent model, indicating the validity of the Condon approximation. Therefore, a trustworthy value can be obtained via this CIS-GMH scheme, with ICA used as a tool to improve and monitor the quality of the results. Systems we tested included a series of rigid, sigma-linked donor-bridge-acceptor compounds where "through-bond" coupling has been previously investigated, and a pair of molecules where "through-space" coupling was experimentally demonstrated. The calculated results agree well with experimentally inferred values in the coupling magnitudes (for both systems studied) and in the exponential distance dependence (for the through-bond series). Our results indicate that this new scheme can properly account for ET coupling arising from both through-bond and through-space mechanisms.
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  • Article
    Zhou Q, Srinivas HD, Zhang S, Watson MP.
    J Am Chem Soc. 2016 09 14;138(36):11989-11995.
    We have developed a stereospecific, nickel-catalyzed Miyaura borylation of allylic pivalates, which delivers highly enantioenriched α-stereogenic γ-aryl allylboronates with good yields and regioselectivities. Our complementary sets of conditions enable access to either enantiomer of allylboronate product from a single enantiomer of readily prepared allylic pivalate substrate. Excellent functional group tolerance, yields, regioselectivities, and stereochemical fidelities are observed. The stereochemical switch from stereoretention to stereoinversion largely depends upon solvent and can be explained by competitive pathways for the oxidative addition step. Our mechanistic investigations support a stereoretentive pathway stemming from a directed oxidative addition and a stereoinvertive pathway that is dominant when MeCN blocks coordination of the directing group by binding the nickel catalyst.
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  • Article
    Hwang JJ, Park MH, Choi SY, Koh JY.
    J Biol Chem. 2005 Mar 25;280(12):11995-2001.
    In certain brain regions, extracellular zinc concentrations can rise precipitously as intense neuronal activity releases large amounts of zinc from the nerve terminals. Although zinc release has been suggested to play a pathological role, its precise physiological effect is poorly understood. Here, we report that exposure to micromolar quantities of zinc for only a few minutes robustly and specifically activated tropomyosin-related kinase (Trk) receptors, most likely TrkB, in cultured cortical neurons. We further found that Trk activation by zinc is extracellularly mediated by activation of metalloproteinases, which release pro-BDNF from cells and convert pro-BDNF to mature BDNF. These results suggest that activity-dependent release of extracellular zinc leads to metalloproteinase activation, which plays a critically important role in Trk receptor activation at zinc-containing synapses.
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  • Article
    Shimizu H, Hosokawa H, Ninomiya H, Miner JH, Masaki T.
    J Biol Chem. 1999 Apr 23;274(17):11995-2000.
    Expression of dystroglycan (DG) by cultured bovine aortic endothelial (BAE) cells was confirmed by cDNA cloning from a BAE cDNA library, Northern blotting of mRNA, Western blotting of membrane proteins, and double immunostaining with antibodies against betaDG and platelet endothelial cell adhesion molecule-1. Immunocytochemical analysis revealed localization of DG in multiple plaques on the basal side of resting cells. This patchy distribution was obscured in migrating cells, in which the most prominent staining was observed in the trailing edge anchoring the cells to the substratum. Biotin-labeled laminin-1 overlay assay of dissociated BAE membrane proteins indicated the interaction of laminin-1 with alphaDG. The laminin alpha5 globular domain fragment expressed in bacteria and labeled with biotin could also bind alphaDG on the membrane blot, and the unlabeled fragment disrupted the binding of biotin-laminin-1 to alphaDG. The interaction of biotin-laminin-1 with alphaDG was inhibited by soluble alphaDG contained in the conditioned medium from DG cDNA-transfected BAE cells and by a series of glycosaminoglycans (heparin, dextran sulfate, and fucoidan). Soluble alphaDG in the conditioned medium inhibited the adhesion of BAE cells to laminin-1-coated dishes, whereas it had no effect on their adhesion to fibronectin. All three glycosaminoglycans that disrupted the biotin-laminin-1 binding to alphaDG inhibited BAE cell adhesion to laminin-1, whereas they failed to inhibit the adhesion to fibronectin. These results indicate a role of DG as a non-integrin laminin receptor involved in vascular endothelial cell adhesion to the extracellular matrix.
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  • Article
    Heinilä MT, Oja AS.
    Phys Rev B Condens Matter. 1994 May 01;49(17):11995-12002.
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  • Article
    Bodewes R, Fraaij PL, Geelhoed-Mieras MM, van Baalen CA, Tiddens HA, van Rossum AM, van der Klis FR, Fouchier RA, Osterhaus AD, Rimmelzwaan GF.
    J Virol. 2011 Nov;85(22):11995-2000.
    Infection with seasonal influenza A viruses induces immunity to potentially pandemic influenza A viruses of other subtypes (heterosubtypic immunity). We recently demonstrated that vaccination against seasonal influenza prevented the induction of heterosubtypic immunity against influenza A/H5N1 virus induced by infection with seasonal influenza in animal models, which correlated with the absence of virus-specific CD8(+) T cell responses. Annual vaccination of all healthy children against influenza has been recommended, but the impact of vaccination on the development of the virus-specific CD8(+) T cell immunity in children is currently unknown. Here we compared the virus-specific CD8(+) T cell immunity in children vaccinated annually with that in unvaccinated children. In the present study, we compared influenza A virus-specific cellular and humoral responses of unvaccinated healthy control children with those of children with cystic fibrosis (CF) who were vaccinated annually. Similar virus-specific CD4(+) T cell and antibody responses were observed, while an age-dependent increase of the virus-specific CD8(+) T cell response that was absent in vaccinated CF children was observed in unvaccinated healthy control children. Our results indicate that annual influenza vaccination is effective against seasonal influenza but hampers the development of virus-specific CD8(+) T cell responses. The consequences of these findings are discussed in the light of the development of protective immunity to seasonal and future pandemic influenza viruses.
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  • Article
    Liu J, Wang C, Zhao H, Zhang J, Ma J, Hou Y, Zou H.
    Int J Clin Exp Med. 2015;8(8):11985-95.
    Locking of central venous catheters with heparin is an accepted practice to maintain catheter patency between dialysis sessions. However, this practice may cause other adverse reactions. Although many studies suggest benefits of other catheter lock solutions over heparin on these grounds, no consensus has been reached for clinical practice. A systematic review and meta-analysis was performed of randomized controlled trials (RCT) that compared antimicrobial-containing or citrate-alone catheter lock solutions with heparin alone in patients undergoing hemodialysis with central venous catheters. Medline, Cochrane Central Register of Controlled Trials from EMBASE, and PubMed were searched for articles published through June 2014. The primary outcomes were catheter-related bacteremia (CRB) and catheter malfunction (CM). The secondary outcomes were bleeding, exit-site infection (ESI), clinical sepsis, and all-cause mortality. Seventeen RCTs met the inclusion criteria. The meta-analysis showed that antimicrobial-containing and citrate-alone lock solutions were superior to heparin for preventing CRB (both P < 0.01). Although antimicrobial-containing lock solutions significantly affected clinical sepsis (P < 0.01), they did not affect ESI, bleeding, or all-cause mortality. Incidence of CM episodes was lower in patients receiving antibiotics + heparin and gentamicin + citrate (both P < 0.05), while other antimicrobial-containing and citrate-alone lock solutions showed no difference. Only citrate-alone lock solutions significantly decreased bleeding and ESI episodes (both P < 0.05). Compared with heparin, antimicrobial-containing lock solutions more effectively prevent CRB and clinical sepsis. Antibiotics + heparin and gentamicin + citrate solutions showing better prevention of CM. Citrate-alone lock solutions result in fewer CRB, bleeding and ESI episodes.
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  • Article
    Ratzinger G, Mitteregger S, Wolf B, Berger R, Zelger B, Weinlich G, Fritsch P, Goebel G, Fiegl H.
    Int J Mol Sci. 2014 Jul 07;15(7):11984-95.
    In this retrospective pilot study, the DNA-methylation status of genes that have been demonstrated to be involved in melanoma carcinogenesis was analyzed in order to identify novel biomarkers for the risk assessment of melanoma patients. We analyzed DNA extracted from punch-biopsies from 68 formalin-fixed paraffin-embedded (FFPE) melanoma specimens. Using MethyLight PCR, we examined 20 genes in specimens from a training set comprising 36 melanoma patients. Selected candidate genes were validated in a test set using FFPE tissue samples from 32 melanoma patients. First, we identified the TNFRSF10D DNA-methylation status (TNFRSF10D methylated vs. unmethylated) as a prognostic marker for overall (p = 0.001) and for relapse-free survival (p = 0.008) in the training set. This finding was confirmed in the independent test set (n = 32; overall survival p = 0.041; relapse-free survival p = 0.012). In a multivariate Cox-regression analysis including all patients, the TNFRSF10D DNA-methylation status remained as the most significant prognostic parameter for overall and relapse-free survival (relative-risk (RR) of death, 4.6 (95% CI: 2.0-11.0; p < 0.001), RR of relapse, 7.2 (95% CI: 2.8-18.3; p < 0.001)). In this study, we demonstrate that TNFRSF10D DNA-methylation analysis of a small tissue-punch from archival FFPE melanoma tissue is a promising approach to provide prognostic information in patients with melanoma.
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  • Article
    Zhou C, Yang P.
    Opt Express. 2015 May 04;23(9):11995-2003.
    At a wavelength corresponding to negligible electromagnetic absorption by ice, rigorous numerical simulations based on solving Maxwell's equations show a backscattering peak associated with the phase function of randomly oriented hexagonal ice crystals. The backscattering peak, which has important implications to the interpretation of lidar observations, exists in the cases of smooth regular, smooth irregular, and roughened hexagonal ice crystals. The backscattering peak width is inversely proportional to the size parameter. The theoretical prediction of the backscattering peak is consistent with observations.
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  • Article
    Hou XY, Huang Z, Guo H, He Y, Chien CC.
    Sci Rep. 2018 Aug 10;8(1):11995.
    The thermal field theory is applied to fermionic superfluids by doubling the degrees of freedom of the BCS theory. We construct the two-mode states and the corresponding Bogoliubov transformation to obtain the BCS thermal vacuum. The expectation values with respect to the BCS thermal vacuum produce the statistical average of the thermodynamic quantities. The BCS thermal vacuum allows a quantum-mechanical perturbation theory with the BCS theory serving as the unperturbed state. We evaluate the leading-order corrections to the order parameter and other physical quantities from the perturbation theory. A direct evaluation of the pairing correlation as a function of temperature shows the pseudogap phenomenon, where the pairing persists when the order parameter vanishes, emerges from the perturbation theory. The correspondence between the thermal vacuum and purification of the density matrix allows a unitary transformation, and we found the geometric phase associated with the transformation in the parameter space.
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  • Article
    U.S. Court of Appeals, District of Columbia Circuit.
    Fed Report. 1993 Jun 11;995:269-73.
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  • Article
    Falden HH, Falster-Hansen KR, Bak KL, Rettrup S, Sauer SP.
    J Phys Chem A. 2009 Oct 29;113(43):11995-2012.
    The performance of the six second order linear response methods RPA(D), SOPPA, SOPPA(CCSD), CIS(D), CC2, and CCSD, which include either noniterative or iterative doubles contributions, has been studied in calculations of vertical excitation energies. The benchmark set consisted of 39 valence and 76 Rydberg states of benzene and five polycyclic aromatic hydrocarbons. As reference values we have used the results of the corresponding calculations with the third order method CCSDR(3), which includes noniterative triples contributions. In addition we have also carried out equivalent calculations at the level of the random phase approximation as well as with the configuration interaction singles and multireference configuration interaction singles and doubles methods.
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  • Article
    Kleyman TR, Cragoe EJ, Kraehenbuhl JP.
    J Biol Chem. 1989 Jul 15;264(20):11995-2000.
    An amiloride-sensitive Na+ channel is found in the apical plasma membrane of high resistance, Na+ transporting epithelia. We have developed a method for the identification of this channel based on the use of a new high affinity photoreactive amiloride analog, 2'-methoxy-5'-nitrobenzamil (NMBA), and anti-amiloride antibodies to identify photolabeled polypeptides. NMBA specifically labels the putative Na+ channel in bovine kidney microsomes. A 130-kDa polypeptide is detected on immunoblots with anti-amiloride antibodies. NMBA is a potent inhibitor of Na+ transport in the established amphibian kidney epithelial cell line A6, and specifically labels a 130-kDa polypeptide. We utilized both NMBA photolabeling and [3H]benzamil binding in order to examine the cellular pool of putative channels following hormonal regulation of Na+ transport. This pool is not significantly altered by the mineralocorticoid agonist aldosterone or antagonist spironolactone, despite a 3.8-fold difference in transepithelial Na+ transport.
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  • Article
    Lamberg A, Helaakoski T, Myllyharju J, Peltonen S, Notbohm H, Pihlajaniemi T, Kivirikko KI.
    J Biol Chem. 1996 May 17;271(20):11988-95.
    An efficient expression system for recombinant collagens would have numerous scientific and practical applications. Nevertheless, most recombinant systems are not suitable for this purpose, as they do not have sufficient amounts of prolyl 4-hydroxylase activity. Pro-alpha 1 chains of human type III collagen expressed in insect cells by a baculovirus vector are reported here to contain significant amounts of 4-hydroxyproline and to form triple-helical molecules, although the Tm of the triple helices was only about 32-34 degrees C. Coexpression of the pro-alpha1(III) chains with the alpha and beta subunits of human prolyl 4-hydroxylase increased the Tm to about 40 degrees C, provided that ascorbate was added to the culture medium. The level of expression of type III procollagen was also increased in the presence of the recombinant prolyl 4-hydroxylase, and the pro-alpha 1(III) chains and alpha1(III) chains were found to be present in disulfide-bonded molecules. Most of the triple-helical collagen produced was retained within the insect cells and could be extracted from the cell pellet. The highest expression levels were obtained in High Five cells, which produced up to about 80 microg of cellular type III collagen (120 microg of procollagen) per 5 X 10(6) cells in monolayer culture and up to 40 mg/liter of cellular type III collagen (60 mg/liter procollagen) in suspension. The 4-hydroxyproline content and Tm of the purified recombinant type III collagen were very similar to those of the nonrecombinant protein, but the hydroxylysine content was slightly lower, being about 3 residues/1000 in the former and 5/1000 in the latter.
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  • Article
    Wang QY, Liu TF, Chu LF, Yao Y, Lu CD.
    Chem Commun (Camb). 2021 Nov 11;57(90):11992-11995.
    In the presence of a chiral spiro phosphoric acid catalyst, the asymmetric reaction of disubstituted ketenes with N-H pyrroles occurred to afford enantioenriched C-acylated pyrroles bearing α-stereogenic carbon centres. The described reaction constitutes a rare example of a catalytic asymmetric reaction of ketenes with carbon-based nucleophiles.
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  • Article
    Wolf AI, Strauman MC, Mozdzanowska K, Whittle JR, Williams KL, Sharpe AH, Weiser JN, Caton AJ, Hensley SE, Erikson J.
    J Virol. 2014 Oct;88(20):11995-2005.
    Pathogen-specific antibodies (Abs) protect against respiratory infection with influenza A virus (IAV) and Streptococcus pneumoniae and are the basis of effective vaccines. Sequential or overlapping coinfections with both pathogens are common, yet the impact of coinfection on the generation and maintenance of Ab responses is largely unknown. We report here that the B cell response to IAV is altered in mice coinfected with IAV and S. pneumoniae and that this response differs, depending on the order of pathogen exposure. In mice exposed to S. pneumoniae prior to IAV, the initial virus-specific germinal center (GC) B cell response is significantly enhanced in the lung-draining mediastinal lymph node and spleen, and there is an increase in CD4(+) T follicular helper (TFH) cell numbers. In contrast, secondary S. pneumoniae infection exaggerates early antiviral antibody-secreting cell formation, and at later times, levels of GCs, TFH cells, and antiviral serum IgG are elevated. Mice exposed to S. pneumoniae prior to IAV do not maintain the initially robust GC response in secondary lymphoid organs and exhibit reduced antiviral serum IgG with diminished virus neutralization activity a month after infection. Our data suggest that the history of pathogen exposures can critically affect the generation of protective antiviral Abs and may partially explain the differential susceptibility to and disease outcomes from IAV infection in humans. Importance: Respiratory tract coinfections, specifically those involving influenza A viruses and Streptococcus pneumoniae, remain a top global health burden. We sought to determine how S. pneumoniae coinfection modulates the B cell immune response to influenza virus since antibodies are key mediators of protection.
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  • Article
    Meidl P, Lehmann A, Bi M, Breitenreiter C, Benkrama J, Li E, Riedo J, Rillig MC.
    Environ Sci Pollut Res Int. 2024 Feb;31(8):11995-12004.
    Natural systems are under increasing pressure by a range of anthropogenic global change factors. Pesticides represent a nearly ubiquitously occurring global change factor and have the potential to affect soil functions. Currently the use of synthetic pesticides is at an all-time high with over 400 active ingredients being utilized in the EU alone, with dozens of these pesticides occurring concurrently in soil. However, we presently do not understand the impacts of the potential interaction of multiple pesticides when applied simultaneously. Using soil collected from a local grassland, we utilize soil microcosms to examine the role of both rate of change and number of a selection of ten currently used pesticides on soil processes, including litter decomposition, water stable aggregates, aggregate size, soil pH, and EC. Additionally, we used null models to enrich our analyses to examine potential patterns caused by interactions between pesticide treatments. We find that both gradual and abrupt pesticide application have negative consequences for soil processes. Notably, pesticide number plays a significant role in affecting soil health. Null models also reveal potential synergistic behavior between pesticides which can further their consequences on soil processes. Our research highlights the complex impacts of pesticides, and the need for environmental policy to address the threats posed by pesticides.
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  • Article
    Abdissa D, Kebede Y, Sudhakar M, Abraham G, Bulcha G, Shiferaw T, Berhanu N, Teshome F, Miecha H, Birhanu Z.
    PLoS Negl Trop Dis. 2024 Mar;18(3):e0011995.
    BACKGROUND: In Ethiopia, Onchocerciasis is a prevalent neglected tropical disease, currently targeted for elimination with mass drug administration and community behavioral changes towards sustained control and eventual elimination. This study aimed to elucidate the awareness, perceptions and practices of endemic communities in Jimma Zone, Ethiopia.
    METHODS AND MATERIALS: Community-based cross-sectional study triangulated with qualitative method was conducted from October-November, 2021. A multistage sampling was employed and data were collected using a pre-tested interviewer-administered structured questionnaire. Logistic regression was used to identify the predictors of comprehensive knowledge and preventive practice. Adjusted odds ratios were calculated at 95% confidence interval (CI) and considered significant with a p-value of <0.05. Kruskal-Whallis and Mann-whitney tests were used to compare median risk perception score by socio-demographic factors. Qualitative data were collected through focus group discussions and key informant interviews and transcribed verbatim. Then the data were coded, categorized, and themes were developed.
    RESULT: The overall prevalence of adequate comprehensive knowledge was 48.8% (95% CI: 44.9, 52.3), high risk perception was 18.7% (95%CI15.9, 21.4) and preventive practice was 46.9%(95%CI:(43.3,50.4). High risk perception[AOR = 1.95 95%CI: (1.32, 2.89] was statistically significant with comprehensive knowledge, likewise knowledge of mode of transmission [AOR = 2.64 95% CI: (1.44, 4.85)], knowledge of consequences [AOR = 2.12 95%CI: (1.21, 3.72)] and knowledge of preventive measures [AOR = 15.65,95%CI:(10.1, 24.2)] were statistically significant with preventive practice. The median risk perception was varied significantly between the groups by educational status, study district and age category. Qualitative evidence showed that there were great community knowledge gap about the disease.
    CONCLUSION: Community knowledge, perceptions, and practices are unacceptably low. Risk perception was significantly associated with comprehensive knowledge, likewise knowledge of mode of transmission, consequences and preventive measures were significantly associated with preventive practice. This implies knowledge is a key component of effective prevention strategies as it is a necessary condition for the behavior change.
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  • Article
    Aridgides DS, Mellinger DL, Gwilt LL, Hampton TH, Mould DL, Hogan DA, Ashare A.
    Sci Rep. 2023 07 25;13(1):11995.
    Macrophage dysfunction has been well-described in Cystic Fibrosis (CF) and may contribute to bacterial persistence in the lung. Whether CF macrophage dysfunction is related directly to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) in macrophages or an indirect consequence of chronic inflammation and mucostasis is a subject of ongoing debate. CFTR modulators that restore CFTR function in epithelial cells improve global CF monocyte inflammatory responses but their direct effects on macrophages are less well understood. To address this knowledge gap, we measured phagocytosis, metabolism, and cytokine expression in response to a classical CF pathogen, Pseudomonas aeruginosa in monocyte-derived macrophages (MDM) isolated from CF F508del homozygous subjects and nonCF controls. Unexpectedly, we found that CFTR modulators enhanced phagocytosis in both CF and nonCF cohorts. CFTR triple modulators also inhibited MDM mitochondrial function, consistent with MDM activation. In contrast to studies in humans where CFTR modulators decreased serum inflammatory cytokine levels, modulators did not alter cytokine secretion in our system. Our studies therefore suggest modulator induced metabolic effects may promote bacterial clearance in both CF and nonCF monocyte-derived macrophages.
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  • Article
    Carr DA, Gómez-Burgaz M, Boudes MC, Peppas NA.
    Ind Eng Chem Res. 2010 Sep 29;49(23):11991-11995.
    The hydrogel system of poly(methacrylic acid-co-N-vinyl pyrrolidone) was evaluated for use as an oral delivery system for growth hormone and salmon calcitonin. These proteins were selected because of their therapeutic importance and the insight provided by evaluating the delivery of a therapeutic agent with a high molecular weight (growth hormone) and a drug with a high isoelectric point (salmon calcitonin). Growth hormone loading and release studies were performed for both P(MAA-co-NVP) and P(MAA-g-PEG). Loading efficiencies for the respective systems were 50.9 ± 1.8% and 57.8 ± 4.1%; weight incorporation of the protein was determined to be 3.5 ± 0.1% and 4.0 ± 0.3%. At pH 7.4, growth hormone release of 90% occurred within 45 min for P(MAA-co-NVP) microparticles; 90% release was not achieved with P(MAA-g-PEG) microparticles until 180 min. At pH 1.2, no release occurred from P(MAA-co-NVP) microparticles but 10% release occurred from P(MAA-g-PEG) microparticles. Salmon calcitonin loading and release were shown to be affected by the negative charges of deprotonated MAA; for systems with monomer molar feed ratios of 4:1, 1:1 and 1:4 MAA:NVP, loading efficiencies were determined to be 70.6 ± 3.0%, 25.3 ± 1.2%, and 1.6 ± 1.3%. Salmon calcitonin release was minimal from the copolymer with 4:1 MAA:NVP monomer feed at pH 7.4. The release improved when the pH was raised above physiological levels. These studies confirmed that P(MAA-co-NVP) was an effective oral delivery system for high molecular weight drugs, but improvements are needed before the system could be utilized for high isoelectric point therapeutic delivery.
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