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Propriedades de transporte de lactato de cálcio em solução aquosa: efeito da temperatura e da presença de B-ciclodextrina

Rita, Marigese Botelho Baia Jesus
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
16.74%
O lactato de cálcio constitui uma das mais importantes fontes de cálcio e tem, em comparação com outros sais de cálcio, uma boa solubilidade e biodisponibilidade. Constitui um suplemento fortificado de cálcio (tanto em bebidas como nos legumes e produtos de carne), aumenta a eficácia dos antioxidantes, impede a descoloração das frutas e vegetais, contribui para manter a densidade dos ossos e, consequentemente, a sua força, e mantém a excitabilidade neuromuscular normal. A caracterização de propriedades de transporte, tais como a difusão, condutibilidade eléctrica e viscosidade, de soluções electrolíticas envolvendo o ião cálcio, em sais de lactato de cálcio, na ausência e na presença de β-ciclodextrina, têm em vista uma melhor compreensão da estrutura dos sistemas e do comportamento termodinâmico de lactato de cálcio em diferentes meios, para aplicação prática em campos como o da medicina e da farmácia. Numa primeira parte deste trabalho mediram-se os coeficientes de difusão de soluções aquosas binárias de lactato de cálcio a 25 ºC, através da técnica de dispersão de Taylor. Foram, também, efectuadas medidas de condutibilidade eléctrica, num intervalo de temperaturas de (15 a 50) ºC, e de viscosidades...

Diffusion of levodopa in aqueous solutions of hydrochloric acid at 25 °C

Barros, Marisa C. F.; Ribeiro, Ana C. F.; Esteso, Miguel A.; Lobo, Victor M. M.; Leaist, Derek G.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
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Ternary mutual diffusion coefficients (D11, D22, D12 and D21) measured by the Taylor dispersion method are reported for aqueous solutions of {levodopa (l-dopa) + HCl} solutions at 25 °C and HCl concentrations up to 0.100 mol · dm−3. The coupled diffusion of l-dopa (1) and HCl (2) is significant, as indicated by large negative cross-diffusion coefficients. D21, for example, reaches values that are larger than D11, the main coefficient of l-dopa. Combined Fick and Nernst–Planck equations are used to analyze the proton coupled diffusion of l-dopa and HCl in terms of the binding of H+ ions to l-dopa and ion migration in the electric field generated by l-dopa and HCl concentration gradients.

FGF2 de 18kDa e de 22,5kDa: sinalização molecular parácrina e funções biológias; FGF2 species of 18 and 22.5 kDa: paracrine molecular signaling and biological functions

Murata, Gilson Masahiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/05/2010 Português
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FGF2 (Fibroblast Growth Factor 2), o fundador da família FGF, tem funções regulatórias na mitogênese, diferenciação, morfogênese e reparo tecidual. Diversas espécies moleculares de FGF2 compartilham uma seqüência C-terminal comum de 155 aminoácidos, pois se originam de diferentes sítios de iniciação de leitura de um único mRNA. O menor, o FGF2-18kDa, é liberado extracelularmente para se ligar a receptores específicos (FGFRs) para disparar as funções parácrinas e autócrinas pelas quais este fator é conhecido. Por outro lado, as espécies maiores (FGF2-21, 22, 22,5 e 34kDa) são intracelulares se ligam a parceiros moleculares desconhecidos para exercer funções intrácrinas ainda indefinidas. O objetivo desta tese foi produzir espécies recombinantes do FGF2-18 e FGF2-22,5, na forma de proteínas de fusão, para analisar funções biológicas e mecanismos de sinalização. Nas células malignas Y1 de camundongo, os recombinantes de FGF2-18kDa (FGF2-18, His-FGF2-18 e His-FGF2-18-ProA) dispararam uma resposta antagônica estimulando as vias de sinalização mitogênica, mas bloqueando o ciclo celular. Nos fibroblastos não tumorigênicos Balb3T3, estes mesmos recombinantes de FGF2-18kDa dispararam apenas a resposta mitogênica clássica. Todos os efeitos biológicos destes recombinantes de FGF2-18kDa foram bloqueados pelo inibidor específico da proteína quinase de tirosina dos FGFRs...

Lean thinking in healthcare services: learning from case studies

Guimarães, Maria Cristina Geraldes Malheiros Machado
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Tese de Doutorado
Publicado em //2013 Português
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Tese de doutoramento em Gestão Geral, Estratégia Desenvolvimento Organizacional/ JEL: D22, I12; Healthcare organisations, especially in public sector, have been adopting Lean management practices with increasing outcomes’ evidences in several parts of the world, since the beginning of this century. However, Lean deployment in Healthcare services has been addressed in the literature in a surgical way by an array of case reports addressing the “hard” side of Lean deployment, sometimes with no result’s consistency or even follow-up analysis. This thesis seek to add to the operational side of Lean deployment in Healthcare, a complementary understanding of Lean deployment approaches, addressing both “hard” and “soft” sides, identifying the real constraints of Lean in Healthcare sector and the sustainability factors. Supported by two main literature reviews and a multi-case approach, a deep research on the eligible Portuguese cases was conducted answering the questions: (i) What are the different outcomes from Lean deployment in Healthcare?; (ii) What are the barriers to Lean implementation in Healthcare?; (iii) What enables Lean implementation in Healthcare?; (iv) What are the risks of Lean in Healthcare?; (v) How to measure Lean achievements in Healthcare services?; and (vi) How to develop a sustainable Lean culture? This contribution to the academic debate on Lean deployment in Healthcare creates clarity on what can be called Lean practices in Healthcare settings under the light of the concept’s founders; what pattern of a Lean deployment journey was followed by Healthcare organisations; and how different cultural (organisational and national) contexts can influence the pace in pursuing that pattern.; As organizações de saúde...

Efeitos da terapia combinada atorvastatina e clopidogrel na biodisponibilidade da estatina e na função plaquetária em pacientes com doença coronária estável

Pinheiro,Luiz Fernando Muniz; Izar,Maria Cristina de Oliveira; Kasmas,Soraia Kani; França,Carolina Nunes; Fischer,Simone Cristina Matheus; Barbosa,Simone Pinto de Melo; Nucci,Gilberto de; Ilha,Jaime; Chen,Lu Chi; Carvalho,Antonio Carlos; Póvoa,Rui Manoe
Fonte: Sociedade Brasileira de Hemodinâmica e Cardiologia Intervencionista - SBHCI Publicador: Sociedade Brasileira de Hemodinâmica e Cardiologia Intervencionista - SBHCI
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2010 Português
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INTRODUÇÃO: Atorvastatina 80 mg é recomendada a pacientes portadores de doença coronária para redução de eventos cardiovasculares, havendo controvérsia sobre as interações farmacocinéticas entre doses elevadas das estatinas e uso concomitante de clopidogrel, por compartilharem a mesma via de biotransformação. Este estudo avaliou os efeitos da terapia combinada atorvastatina/clopidogrel na farmacocinética da estatina e função plaquetária em pacientes com doença coronária estável, sob uso crônico e efetivo de estatina MÉTODO: Os pacientes foram admitidos quatro vezes para internação (V1 a V4) em leito-dia. Sete dias (D) antes da primeira internação a estatina em uso foi suspensa. A seguir, receberam atorvastatina 80 mg (D1 a D22) e clopidogrel 75 mg/dia (D8 a D29). Em todas as V foram obtidas amostras de sangue em jejum para dosagens lipídicas, avaliação da função plaquetária (técnica da placa e cone) e quantificação dos níveis plasmáticos de atorvastatina (cromatografia líquida e espectrometria de massa) RESULTADOS: A suspensão por uma semana da estatina modificou o perfil lipídico (P < 0,05 vs. basal), ocorrendo rápida melhora de todas as frações lipídicas após atorvastatina 80 mg (P < 0...

Characterization of Arabidopsis thaliana cDNAs that render yeasts tolerant toward the thiol-oxidizing drug diamide.

Kushnir, S; Babiychuk, E; Kampfenkel, K; Belles-Boix, E; Van Montagu, M; Inzé, D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 07/11/1995 Português
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Diamide oxidizes cellular thiols and induces oxidative stress. To isolate plant genes which may, when overexpressed, increase tolerance of plants toward oxidative damage, an in vivo diamide tolerance screening in yeasts was used. An Arabidopsis cDNA library in a yeast expression vector was used to transform a yeast strain with intact antioxidant defense. Cells from approximately 10(5) primary transformants were selected for resistance to diamide. Three Arabidopsis cDNAs which confer diamide tolerance were isolated. This drug tolerance was specific and no cross tolerance toward hydroperoxides was found. One cDNA (D3) encodes a polypeptide which has an amino-terminal J domain characteristic of a divergent family of DnaJ chaperones. Another (D18) encodes a putative dTDP-D-glucose 4,6-dehydratase. Surprisingly, the third cDNA (D22) encodes a plant homolog of gamma-glutamyltransferases. It would have been difficult to predict that the expression of those genes would lead to an improved survival under conditions of depletion of cellular thiols. Hence, we suggest that this cloning approach may be a useful contribution to the isolation of plant genes that can help to cope with oxidative stress.

ICP22 and the UL13 Protein Kinase Are both Required for Herpes Simplex Virus-Induced Modification of the Large Subunit of RNA Polymerase II

Long, Melissa C.; Leong, Vivian; Schaffer, Priscilla A.; Spencer, Charlotte A.; Rice, Stephen A.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/1999 Português
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Herpes simplex virus type 1 (HSV-1) infection alters the phosphorylation of the large subunit of RNA polymerase II (RNAP II), resulting in the depletion of the hypophosphorylated and hyperphosphorylated forms of this polypeptide (known as IIa and IIo, respectively) and induction of a novel, alternatively phosphorylated form (designated IIi). We previously showed that the HSV-1 immediate-early protein ICP22 is involved in this phenomenon, since induction of IIi and depletion of IIa are deficient in cells infected with 22/n199, an HSV-1 ICP22 nonsense mutant (S. A. Rice, M. C. Long, V. Lam, P. A. Schaffer, and C. A. Spencer, J. Virol. 69:5550–5559, 1995). However, depletion of IIo still occurs in 22/n199-infected cells. This suggests either that another viral gene product affects the RNAP II large subunit or that the truncated ICP22 polypeptide encoded by 22/n199 retains residual activity which leads to IIo depletion. To distinguish between these possibilities, we engineered an HSV-1 ICP22 null mutant, d22-lacZ, and compared it to 22/n199. The two mutants are indistinguishable in their effects on the RNAP II large subunit, suggesting that an additional viral gene product is involved in altering RNAP II. Two candidates are UL13, a protein kinase which has been implicated in ICP22 phosphorylation...

Natural transmission of Pneumocystis carinii in nonimmunosuppressed animals: early contagiousness of experimentally infected rabbits (Oryctolagus cuniculus).

Ceré, N; Polack, B; Chanteloup, N K; Coudert, P
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1997 Português
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Airborne transmission of Pneumocystis carinii has been established, but the infective form and the sources of infection remain unknown. Animal models for studies of P. carinii have previously been limited to immunosuppressed rodents; however, this study was performed with nonimmunodepressed P. carinii-free rabbits. This study was aimed at determining (i) the delay between inoculation of animals (day zero [D0]) and the onset of contagiousness and (ii) the end of contagiousness of these animals (donors). Five-week-old rabbits were used as contact animals and were housed with the donors. The cohabitation periods were for 4 or 5 days from D0 to D4, D4 to D8, D8 to D13, D13 to D18, and D18 to D22. The highest parasite burdens were observed in contact animals housed with donors from D8 to D13 or D13 to D18. This period (8th to 18th day following the day of inoculation of donors) might correspond to the highest phase of contagiousness of donors.

Septum Formation in Escherichia coli: Characterization of Septal Structure and the Effects of Antibiotics on Cell Division

Burdett, I. D. J.; Murray, R. G. E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1974 Português
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Septa can be demonstrated in sections of Escherichia coli strains B and B/r after fixation with acrolein and glutaraldehyde. The septum consists of an ingrowth of the cytoplasmic membrane and the mucopeptide layer; the outer membrane is excluded from the septum until the cells begin to separate. Mesosomes have also been observed. The septum is highly labile and, except in the chain-forming strains, E. coli D22 env A and CRT 97, not easily preserved by standard procedures. The labile nature of the septum may be due to the presence of autolysin(s) located at the presumptive division site. Blocking division by addition of ampicillin (2 to 5 μg/ml) to cells of E. coli B/r produces a bulge at the middle of the cells; bulge formation is stopped by addition of chloramphenicol. Cephalosporins also induce bulge formation but may stop cell elongation as well as division. Bulge formation, due to the presumed action of an autolysin(s), may be an initial step in the septation sequence when the mucopeptide is modified to allow construction of the septum. In a nonseptate filament-forming strain, PAT 84, which ceases to divide at 42 C, bulge formation only occurs in the presence of ampicillin at the time of a shift-down at 30 C or at 42 C in the presence of NaCl (0.25 to 0.34 M). Experiments with chloramphenicol suggest that the filaments are fully compartmentalized but fail to divide owing to the inactivation...

Outer-Membrane Penetration Barriers as Components of Intrinsic Resistance to Beta-Lactam and Other Antibiotics in Escherichia coli K-12

Scudamore, R. Allan; Beveridge, Terrance J.; Goldner, Morris
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1979 Português
Relevância na Pesquisa
16.74%
A new technique has been devised to investigate the penetration of antibiotics through the gram-negative outer membrane; the application here was to study intrinsic resistance of Escherichia coli K-12. Exponential cells in broth were briefly treated with 2.5 mM ethylenediaminetetraacetic acid at 5°C to disrupt the outer membrane penetration barrier, and the response of treated and untreated cells to antibiotics was compared by turbidimetry. A barrier index was derived to describe the ability of 7 beta-lactam and 10 other antibiotics to penetrate the outer membrane of strain Y10. There was correlation between the molecular weight and log10 barrier index (r = 0.59, P ≅ 0.01). The envelope mutant D22 (envA) had low barrier indexes for erythromycin, rifampin, ampicillin, and cloxacillin. For the beta-lactams, outer membrane penetration and affinity for inner membrane target site(s) triggering cell lysis were measured as independent components of the overall activity; although penetration and overall activity varied greatly, the affinities of most were within a narrow range.

Characterizations of Adenovirus Type 41 Isolates from Children with Acute Gastroenteritis in Japan, Vietnam, and Korea

Li, Lei; Shimizu, Hideaki; Doan, Lan Thi Phuong; Tung, Phan Gia; Okitsu, Shoko; Nishio, Osamu; Suzuki, Eiko; Seo, Jeong Kee; Kim, Kyo Sun; Müller, Werner E. G.; Ushijima, Hiroshi
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /09/2004 Português
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Genetic and antigenic characterizations of 70 strains of adenovirus type 41 (Ad41), isolated between 1998 and 2001 from children in Japan, Vietnam, and Korea, were done by DNA restriction enzyme (RE) analysis, sequencing analysis, and monoclonal antibody (MAb)-based enzyme-linked immunosorbent assay (ELISA). Eight genome types were observed in the present study, among which D25, D26, D27, and D28 were novel genome types. These eight genome types were divided into two genome-type clusters (GTCs) based on phylogenetic analysis of the hypervariable regions (HVRs) of the hexon. GTC1 includes D1, D25, D26, D27, and D28, and the GTC2 contains D4, D12, and D22. The amino acid homologies among the members within a GTC were 97 to 100%, whereas between the members of different GTCs the homologies were 92 to 94%. The specificity of the GTC classification was confirmed by ELISA with MAb 1F, which was selected by the Ad41 prototype Tak strain. It was found that only the isolates of GTC1 but not of GTC2 reacted with MAb 1F. These results suggest that Ad41 isolates from the three countries should be classified into two subtypes. The accumulation of amino acid mutations located in HVRs of hexon are indicative for the classification of Ad41 subtype.

Multilayer Polyelectrolyte Films Functionalized by Insertion of Defensin: a New Approach to Protection of Implants from Bacterial Colonization

Etienne, O.; Picart, C.; Taddei, C.; Haikel, Y.; Dimarcq, J. L.; Schaaf, P.; Voegel, J. C.; Ogier, J. A.; Egles, C.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/2004 Português
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Infection of implanted materials by bacteria constitutes one of the most serious complications following prosthetic surgery. In the present study, we developed a new strategy based on the insertion of an antimicrobial peptide (defensin from Anopheles gambiae mosquitoes) into polyelectrolyte multilayer films built by the alternate deposition of polyanions and polycations. Quartz crystal microbalance and streaming potential measurements were used to follow step by step the construction of the multilayer films and embedding of the defensin within the films. Antimicrobial assays were performed with two strains: Micrococcus luteus (a gram-positive bacterium) and Escherichia coli D22 (a gram-negative bacterium). The inhibition of E. coli D22 growth at the surface of defensin-functionalized films was found to be 98% when 10 antimicrobial peptide layers were inserted in the film architecture. Noticeably, the biofunctionalization could be achieved only when positively charged poly(l-lysine) was the outermost layer of the film. On the basis of the results of bacterial adhesion experiments observed by confocal or electron microscopy, these observations could result from the close interaction of the bacteria with the positively charged ends of the films...

Mechanisms of Zoonotic Severe Acute Respiratory Syndrome Coronavirus Host Range Expansion in Human Airway Epithelium▿

Sheahan, Timothy; Rockx, Barry; Donaldson, Eric; Sims, Amy; Pickles, Raymond; Corti, Davide; Baric, Ralph
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.74%
In 2003, severe acute respiratory syndrome coronavirus (SARS-CoV) emerged and caused over 8,000 human cases of infection and more than 700 deaths worldwide. Zoonotic SARS-CoV likely evolved to infect humans by a series of transmission events between humans and animals for sale in China. Using synthetic biology, we engineered the spike protein (S) from a civet strain, SZ16, into our epidemic strain infectious clone, creating the chimeric virus icSZ16-S, which was infectious but yielded progeny viruses incapable of propagating in vitro. After introducing a K479N mutation within the S receptor binding domain (RBD) of SZ16, the recombinant virus (icSZ16-S K479N) replicated in Vero cells but was severely debilitated in growth. The in vitro evolution of icSZ16-S K479N on human airway epithelial (HAE) cells produced two viruses (icSZ16-S K479N D8 and D22) with enhanced growth on HAE cells and on delayed brain tumor cells expressing the SARS-CoV receptor, human angiotensin I converting enzyme 2 (hACE2). The icSZ16-S K479N D8 and D22 virus RBDs contained mutations in ACE2 contact residues, Y442F and L472F, that remodeled S interactions with hACE2. Further, these viruses were neutralized by a human monoclonal antibody (MAb), S230.15, but the parent icSZ16-S K479N strain was eight times more resistant than the mutants. These data suggest that the human adaptation of zoonotic SARS-CoV strains may select for some variants that are highly susceptible to select MAbs that bind to RBDs. The epidemic...

Evidence of Molecular Evolution Driven by Recombination Events Influencing Tropism in a Novel Human Adenovirus that Causes Epidemic Keratoconjunctivitis

Walsh, Michael P.; Chintakuntlawar, Ashish; Robinson, Christopher M.; Madisch, Ijad; Harrach, Balázs; Hudson, Nolan R.; Schnurr, David; Heim, Albert; Chodosh, James; Seto, Donald; Jones, Morris S.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/06/2009 Português
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18.2%
In 2005, a human adenovirus strain (formerly known as HAdV-D22/H8 but renamed here HAdV-D53) was isolated from an outbreak of epidemic keratoconjunctititis (EKC), a disease that is usually caused by HAdV-D8, -D19, or -D37, not HAdV-D22. To date, a complete change of tropism compared to the prototype has never been observed, although apparent recombinant strains of other viruses from species Human adenovirus D (HAdV-D) have been described. The complete genome of HAdV-D53 was sequenced to elucidate recombination events that lead to the emergence of a viable and highly virulent virus with a modified tropism. Bioinformatic and phylogenetic analyses of this genome demonstrate that this adenovirus is a recombinant of HAdV-D8 (including the fiber gene encoding the primary cellular receptor binding site), HAdV-D22, (the ε determinant of the hexon gene), HAdV-D37 (including the penton base gene encoding the secondary cellular receptor binding site), and at least one unknown or unsequenced HAdV-D strain. Bootscanning analysis of the complete genomic sequence of this novel adenovirus, which we have re-named HAdV-D53, indicated at least five recombination events between the aforementioned adenoviruses. Intrahexon recombination sites perfectly framed the ε neutralization determinant that was almost identical to the HAdV-D22 prototype. Additional bootscan analysis of all HAdV-D hexon genes revealed recombinations in identical locations in several other adenoviruses. In addition...

Computational Analysis of Human Adenovirus Type 22 Provides Evidence for Recombination among Species D Human Adenoviruses in the Penton Base Gene ▿

Robinson, Christopher M.; Rajaiya, Jaya; Walsh, Michael P.; Seto, Donald; Dyer, David W.; Jones, Morris S.; Chodosh, James
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
16.74%
Recombination in human adenoviruses (HAdV) may confer virulence upon an otherwise nonvirulent strain. The genome sequence of species D HAdV type 22 (HAdV-D22) revealed evidence for recombination with HAdV-D19 and HAdV-D37 within the capsid penton base gene. Bootscan analysis demonstrated that recombination sites within the penton base gene frame the coding sequences for the two external hypervariable loops in the protein. A similar pattern of recombination was evident within other HAdV-D types but not other HAdV species. Further study of recombination among HAdVs is needed to better predict possible recombination events among wild-type viruses and adenoviral gene therapy vectors.

MEMBRANE POTENTIAL AND pH-DEPENDENT ACCUMULATION OF DECYNIUM-22 (1,1′-DIETHYL-2,2′-CYANINE IODIDE) FLUORESCENCE THROUGH OCT TRANSPORTERS IN ASTROCYTES

Inyushin, Mikhail; Kucheryavykh, Yuri; Kucheryavykh, Lilia; Sanabria, Priscilla; Jiménez-Rivera, Carlos; Struganova, Irina; Eaton, Misty; Skatchkov, Serguei
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
Relevância na Pesquisa
17.96%
1,1′-Diethyl-2,2′-cyanine iodide (decynium22; D22) is a potent blocker of the organic cation family of transporters (EMT/OCT) known to move endogenous monoamines like dopamine and norepinephrine across cell membranes. Decynium22 is a cation with a relatively high affinity for all members of the OCT family in both human and rat cells. The mechanism through which decynium22 blocks OCT transporters is poorly understood. We tested the hypothesis that denynium22 may compete with monoamines utilizing OCT to permeate the cells. Using the ability of D22 to aggregate and produce fluorescence at 570 nm, we measured D22 uptake in cultured astrocytes. The rate of D22 uptake was strongly depressed by acid pH and by elevated external K+. The rate of uptake was similar to that displayed by 4-(4-(dimethylamino)-styryl)-N-methylpyridinium (ASP+), a well established substrate for OCT and high-affinity Na+-dependent monoamine transporters. These data were supported by measurement of electrogenic uptake using whole cell voltage clamp recording. Decynium22 depressed norepinephrine, but not glutamate uptake. These data are also consistent with the described OCT transporter characteristics. Taken together, our results suggest that decynium22 accumulation might be a useful instrument to study monoamine transport in the brain...

Evidence of Molecular Evolution Driven by Recombination Events Influencing Tropism in a Novel Human Adenovirus that Causes Epidemic Keratoconjunctivitis

Walsh, Michael P.; Chintakuntlawar, Ashish; Harrach, Balázs; Hudson, Nolan R.; Schnurr, David; Heim, Albert; Seto, Donald; Jones, Morris S.; Robinson, Christopher; Madisch, Ijad; Chodosh, James
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
18.2%
In 2005, a human adenovirus strain (formerly known as HAdV-D22/H8 but renamed here HAdV-D53) was isolated from an outbreak of epidemic keratoconjunctititis (EKC), a disease that is usually caused by HAdV-D8, -D19, or -D37, not HAdV-D22. To date, a complete change of tropism compared to the prototype has never been observed, although apparent recombinant strains of other viruses from species Human adenovirus D (HAdV-D) have been described. The complete genome of HAdV-D53 was sequenced to elucidate recombination events that lead to the emergence of a viable and highly virulent virus with a modified tropism. Bioinformatic and phylogenetic analyses of this genome demonstrate that this adenovirus is a recombinant of HAdV-D8 (including the fiber gene encoding the primary cellular receptor binding site), HAdV-D22, (the ε determinant of the hexon gene), HAdV-D37 (including the penton base gene encoding the secondary cellular receptor binding site), and at least one unknown or unsequenced HAdV-D strain. Bootscanning analysis of the complete genomic sequence of this novel adenovirus, which we have re-named HAdV-D53, indicated at least five recombination events between the aforementioned adenoviruses. Intrahexon recombination sites perfectly framed the ε neutralization determinant that was almost identical to the HAdV-D22 prototype. Additional bootscan analysis of all HAdV-D hexon genes revealed recombinations in identical locations in several other adenoviruses. In addition...

Characterization of a candidate gene for drought tolerance in Coffea: the CcDREB1D gene, in contrasting genotypes of Coffea canephora and related species

Alves, Gabriel Sérgio Costa
Fonte: Universidade Federal de Lavras; Programa de Pós-Graduação em Biotecnologia Vegetal; UFLA; brasil; Não especifica vinculação com nenhum departamento Publicador: Universidade Federal de Lavras; Programa de Pós-Graduação em Biotecnologia Vegetal; UFLA; brasil; Não especifica vinculação com nenhum departamento
Tipo: Tese de Doutorado
Publicado em 04/11/2015 Português
Relevância na Pesquisa
17.4%
Drought is the key factor affecting plant development, flowering, productivity, fruits development and their quality. In several plant species, the DREBs genes play a key role in plant responses to abiotic stress. In coffee, several candidate genes for drought tolerance have been identified, like CcDREB1D that showed increased gene expression upon drought stress mainly in leaves of Coffea canephora drought-tolerant clones. Based on these information, an in depth characterization of DREB1D was initiated by (i) studying the genetic diversity present in DREB1D loci in C. canephora and C. arabica, (ii) identifying DREB coffee subfamily members and evaluating phylogenetic relations between CcDREB1D and homologs from other plant species, and (iii) performing a functional characterization of CcDREB1D promoters by homologous genetic transformation of C. arabica. Our findings show several evidences of association between drought tolerance and the genetic variations on DREB1D promoter region. Further analyses indicated that these promoters are evolving by the rearrangement of cis-regulatory elements, and could influence DREB1D expression. The recent release of the C. canephora genome sequence allowed us to identify the DREB gene family in this species composed of at least 31 canonical DREB genes. Compared to other plants...

Changes in deoxyribonucleic acid polymerase activities in synthesis of deoxyribonucleic acid during sporulation of Bacillus subtilis.

Honjo, M; Shibano, Y; Komano, T
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1976 Português
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17.4%
The deoxyribonucleic acid (DNA) polymerase activities in Bacillus subtilis strains Marburg 168 (thy-trp2) and D22, a DNA polymerase I-deficient mutant, were measured at various stages of sporulation. The DNA polymerase I activity, which had decreased after the exponential growth, began to increase at the early stage of sporulation, reached a maximum and then again decreased. The activity of neither DNA polymerase II nor III was observed to change so drastically as that of DNA polymerase I during sporulation. The incorporation of [3H]deoxythymidine 5'-triphosphate ([3H]dTTP) into Brij 58-treated permeable cells increased during sporulation. The stimulation of [3H]dTTP incorporation into the cells by irradiation with ultraviolet light was also observed to coincide with DNA polymerase I activity. In strain D22 the activities of DNA polymerase II and III were almost constant with time. Neither change of [3H]dTTP incorporation into Brij 58-treated cells nor stimulation of incorporation by irradiation with ultraviolet light was observed.

Quark mass matrices and observable quantities

Falcone, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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A nearly historical account of quark mass matrix models is given, and the structure of quark mass matrices in the Standard Model is studied. For a minimal parameter basis suggested earlier, where $M_u$ is diagonal and $M_{d11}$, $M_{d13}$, $M_{d31}$ are zero, the dependence of mass matrices on the CP violating phase $\delta$ of $V_{CKM}$ is reported: all parameters are almost independent, except $M_{d22}$ and $M_{d23}$, and the equality $|M_{d22}|=M_{d23}$ is obtained for a value of $\delta$ very close to the value which is favoured by experiments. Moreover, on this basis, $M_{d12} \simeq M_{d21}$ and $M_{d33} \simeq 2M_{d32}$. Some comments on mass matrices in left-right symmetric models are added.; Comment: 19 pages, Revtex. Numerical values in Eqn.(45) corrected. Minor changes