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1.
Plants (Basel) ; 11(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36559677

RESUMO

Phenolic compounds of 25 newly introduced strawberry cultivars were profiled using spectrophotometry, electron paramagnetic resonance (EPR) spectroscopy, and high-performance liquid chromatography-mass spectrometry. Total phenolic and anthocyanin content (TPC and TACY, respectively), as well as vitamin C, and concentrations of individual phenolic compounds in fruits were evaluated to identify the most promising cultivars according to their phenolic profile. The highest values of TPC, TACY, and vitamin C were recorded in 'Premy' (1.53 mg eq GA g-1 FW), 'Sandra' (30.60 mg eq Pg-3-g 100 g-1 FW), and 'Laetitia' (56.32 mg 100 g-1 FW), respectively. The DPPH and •OH radicals scavenging activity of fruit methanolic extracts was estimated using EPR spectroscopy. All cultivars are almost uniformly effective in the scavenging of •OH radical, while 'Tea', 'Premy', and 'Joly' were marked as highly potent cultivars (over 70%) in terms of DPPH-antiradical activity. Specific peroxidase activities were the highest in 'Garda', 'Federica', and 'Rumba' (0.11, 0.08, and 0.06 U mg-1 prot, respectively). 'Laetitia', 'Joly', 'Arianna', 'Tea', and 'Mila' cultivars were distinguished from others as the richest concerning almost all flavonoids and phenolic acids, including some other parameters of bioactivity. These cultivars could be recommended to consumers as functional fruit foods.

2.
J Appl Crystallogr ; 55(Pt 4): 787-812, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35974720

RESUMO

In the analysis of neutron scattering measurements of condensed matter structure, it normally suffices to treat the incident and scattered neutron beams as if composed of incoherent distributions of plane waves with wavevectors of different magnitudes and directions that are taken to define an instrumental resolution. However, despite the wide-ranging applicability of this conventional treatment, there are cases, such as specular neutron reflectometry, in which the structural length scales of the scattering object require that the wavefunction of an individual neutron in the beam be described by a spatially localized packet - in particular with respect to the transverse extent of its wavefronts (i.e. normal to the packet's mean direction of propagation). It is shown in the present work that neutron diffraction patterns observed for periodic transmission phase gratings, as well as specular reflection measurements from patterned thin films with repeat units of the order of micrometres, can be accurately described by associating an individual neutron with a wave packet and treating a beam as a collection of independent packets. In these cases, accurate analysis requires that the transverse spatial extent of a neutron packet wavefront be accounted for in addition to the angular divergence of the beam that is characterized by a distribution of packet mean wavevector directions. It is shown how a measure of the effective transverse spatial extent of the neutron packet - over which its wavefronts are of sufficient uniformity to produce coherent scattering - can be determined by employing reference diffraction gratings and patterned thin films of known structure and composition.

3.
Aust Crit Care ; 35(3): 302-308, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34419341

RESUMO

BACKGROUND: Acute respiratory failure (ARF) has become one of the most prevalent serious pathologies encountered in the emergency medical service (EMS). In hospital settings, noninvasive ventilation (NIV) therapy prevents complications from more aggressive treatments for that condition. However, the scarce evidence on the benefits of NIV in prehospital EMS (i.e., during transport to the hospital) is inconclusive. OBJECTIVES: To determine whether the administration of NIV during prehospital EMS in cases of ARF reduces in-hospital mortality compared with starting NIV on arrival to in-patient EMS. METHODS: This is a multicentre, observational, prospective cohort study. We recruited a total of 317 patients from the Madrid region (Spain) who were prescribed NIV for their ARF using a nonprobabilistic consecutive sampling method. Analyses of the main outcome (in-hospital mortality) and secondary outcomes (length of hospital stay, readmissions, percentage of intensive care unit admissions, and cost-effectiveness) will include descriptive analyses of patients' characteristics, as well as bivariate and multivariate analyses and cost-effectiveness analysis. DISCUSSION: This study will provide data on NIV management in prehospital and in-patient EMS in patients with ARF. Results will contribute to the existing evidence on the benefits of NIV in the context of prehospital EMS while underlining the importance of a standardized formal training for physicians and nurses working in prehospital and in-patient EMSs. CONCLUSION: The VentilaMadrid study will provide valuable data on the clinical factors of patients receiving NIV in prehospital EMS. Further, were our hypothesis to be confirmed, our results would strongly suggest that the administration of NIV in prehospital EMS by medical and nursing profesionals formally trained in the technique reduces mortality and improves prognoses.


Assuntos
Serviços Médicos de Emergência , Ventilação não Invasiva , Síndrome do Desconforto Respiratório , Estudos de Coortes , Serviços Médicos de Emergência/métodos , Humanos , Estudos Multicêntricos como Assunto , Ventilação não Invasiva/métodos , Estudos Observacionais como Assunto , Estudos Prospectivos , Espanha
4.
J Chem Phys ; 145(1): 011101, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27394091

RESUMO

Time-resolved extreme ultraviolet (XUV) transient absorption spectroscopy of iodomethane and iodobenzene photodissociation at the iodine pre-N4,5 edge is presented, using femtosecond UV pump pulses and XUV probe pulses from high harmonic generation. For both molecules the molecular core-to-valence absorption lines fade immediately, within the pump-probe time-resolution. Absorption lines converging to the atomic iodine product emerge promptly in CH3I but are time-delayed in C6H5I. We attribute this delay to the initial π → σ(*) excitation in iodobenzene, which is distant from the iodine reporter atom. We measure a continuous shift in energy of the emerging atomic absorption lines in CH3I, attributed to relaxation of the excited valence shell. An independent particle model is used to rationalize the observed experimental findings.

5.
An Pediatr (Barc) ; 84(2): 79-84, 2016 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-26028565

RESUMO

INTRODUCTION: Surfactant delivered using a minimally invasive technique, known as MIST (Minimally Invasive Surfactant Therapy) is a method which allows surfactant to be administered to a patient connected to non-invasive respiratory support. This is an increasingly used therapy in Neonatal Units that reduces the intubation rate and the pathology associated with intubation and allows the surfactant to be administered to the patients who clinically need it. PATIENTS AND METHODS: In years 2013 and 2014 in the Hospital General Universitario de Elche surfactant was delivered using this method to 19 patients, five of whom were 28 or less weeks of gestation age at birth. A comparison is made with a historical cohort consisting of 28 patients with Respiratory Distress Syndrome treated initially with non-invasive respiratory support. RESULTS: No incidents were recorded that caused the interruption of the administration. A reduction in the fraction of inspired oxygen was observed in all cases after surfactant administration. Fewer intubations in the first 72 hours of life were found in the treatment group compared to the control group (42% vs. 54%). DISCUSSION: The experience recorded in the Hospital General Universitario de Elche shows that the administration of surfactant using a MIST technique is a reproducible method of treatment, which allows the surfactant distribution during spontaneous breathing with non invasive respiratory support.


Assuntos
Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Tensoativos/uso terapêutico , Administração por Inalação , Aerossóis , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Surfactantes Pulmonares/administração & dosagem , Tensoativos/administração & dosagem , Centros de Atenção Terciária
6.
Phys Chem Chem Phys ; 17(17): 11301-12, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25839065

RESUMO

Structure and composition of an 11 nm thick amorphous silicon (a-Si) thin film anode, capped with 4 nm of alumina are measured, in operando, by neutron reflectivity (NR) and electrochemical impedance spectroscopy in a lithium half-cell. NR data are analyzed to quantify the a-Si thickness and composition at various states of charge over six cycles. The a-Si anode expands and contracts upon lithiation and delithiation, respectively, while maintaining its integrity and low interfacial roughness (≤1.6 nm) throughout the cycling. The apparently non-linear expansion of the a-Si layer volume versus lithium content agrees with previous thin-film a-Si anode studies. However, a proposed pore collapse and regrowth (PCRG) mechanism establishes that the solid domains in the porous LixSi film expand linearly with Li content at 8.48 cm(3) mol(-1) Li, similar to crystalline Si. In the PCRG model, porosity is first consumed by expansion of solid domains upon lithiation, after which the film as a whole expands. Porosity is reestablished at 5-28% upon delithiation. Data show that the alumina protective layer on the a-Si film functions as an effective artificial solid electrolyte interphase (SEI), maintaining its structural integrity, low interfacial roughness, and relatively small transport resistance. No additional spontaneously-formed SEI is observed in this study.

7.
J Chem Phys ; 141(7): 071102, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25149767

RESUMO

Ion conduction mechanisms and the nanostructure of ion conduction networks remain poorly understood in polymer electrolytes which are used as proton-exchange-membranes (PEM) in fuel cell applications. Here we study nanoscale surface-potential fluctuations produced by Brownian ion dynamics in thin films of low-hydration Nafion™, the prototype PEM. Images and power spectra of the fluctuations are used to derive the local conductivity-relaxation spectrum, in order to compare with bulk behavior and hopping-conductivity models. Conductivity relaxation-times ranged from hours to milliseconds, depending on hydration and temperature, demonstrating that the observed fluctuations are produced by water-facilitated hydrogen-ion hopping within the ion-channel network. Due to the small number of ions probed, non-Gaussian statistics of the fluctuations can be used to constrain ion conduction parameters and mechanisms.

8.
Sci Rep ; 3: 2675, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24043222

RESUMO

Strong-field ionisation surprises with richness beyond current understanding despite decade long investigations. Ionisation with mid-IR light has promptly revealed unexpected kinetic energy structures that seem related to unanticipated quantum trajectories of the electrons. We measure first 3D momentum distributions in the deep tunneling regime (γ = 0.3) and observe surprising new electron dynamics of near-zero momentum electrons and extremely low momentum structures, below the eV, despite very high quiver energies of 95 eV. Such level of high-precision measurements at only 1 meV above the threshold, despite 5 orders higher ponderomotive energies, has now become possible with a specifically developed ultrafast mid-IR light source in combination with a reaction microscope, thereby permitting a new level of investigations into mid-IR recollision physics.

9.
Langmuir ; 28(28): 10504-20, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22686684

RESUMO

The voltage-sensor domain (VSD) is a modular four-helix bundle component that confers voltage sensitivity to voltage-gated cation channels in biological membranes. Despite extensive biophysical studies and the recent availability of X-ray crystal structures for a few voltage-gated potassium (Kv) channels and a voltage-gate sodium (Nav) channel, a complete understanding of the cooperative mechanism of electromechanical coupling, interconverting the closed-to-open states (i.e., nonconducting to cation conducting) remains undetermined. Moreover, the function of these domains is highly dependent on the physical-chemical properties of the surrounding lipid membrane environment. The basis for this work was provided by a recent structural study of the VSD from a prokaryotic Kv-channel vectorially oriented within a single phospholipid (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)) membrane investigated by X-ray interferometry at the solid/moist He (or solid/vapor) and solid/liquid interfaces, thus achieving partial to full hydration, respectively (Gupta et al. Phys. Rev. E2011, 84, 031911-1-15). Here, we utilize neutron interferometry to characterize this system in substantially greater structural detail at the submolecular level, due to its inherent advantages arising from solvent contrast variation coupled with the deuteration of selected submolecular membrane components, especially important for the membrane at the solid/liquid interface. We demonstrate the unique vectorial orientation of the VSD and the retention of its molecular conformation manifest in the asymmetric profile structure of the protein within the profile structure of this single bilayer membrane system. We definitively characterize the asymmetric phospholipid bilayer solvating the lateral surfaces of the VSD protein within the membrane. The profile structures of both the VSD protein and phospholipid bilayer depend upon the hydration state of the membrane. We also determine the distribution of water and exchangeable hydrogen throughout the profile structure of both the VSD itself and the VSD:POPC membrane. These two experimentally determined water and exchangeable hydrogen distribution profiles are in good agreement with molecular dynamics simulations of the VSD protein vectorially oriented within a fully hydrated POPC bilayer membrane, supporting the existence of the VSD's water pore. This approach was extended to the full-length Kv-channel (KvAP) at a solid/liquid interface, providing the separate profile structures of the KvAP protein and the POPC bilayer within the reconstituted KvAP:POPC membrane.


Assuntos
Ativação do Canal Iônico , Bicamadas Lipídicas/química , Nêutrons , Canais de Potássio de Abertura Dependente da Tensão da Membrana/química , Interferometria , Estrutura Molecular , Fosfolipídeos/química
10.
J Phys Chem A ; 116(11): 2662-8, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22112209

RESUMO

We study ionization of molecules by an intense laser field over a broad wavelength regime, ranging from 0.8 to 1.5 µm experimentally and from 0.6 to 10 µm theoretically. A reaction microscope is combined with an optical parametric amplifier to achieve ionization yields in the near-infrared wavelength regime. Calculations are done using the strong-field S-matrix theory and agreement is found between experiment and theory, showing that ionization of many molecules is suppressed compared to the ionization of atoms with identical ionization potentials at near-infrared wavelengths at around 0.8 µm, but not at longest wavelengths (10 µm). This is due to interference effects in the electron emission that are effective at low photoelectron energies but tend to average out at higher energies. We observe the transition between suppression and nonsuppression of molecular ionization in the near-infrared wavelength regime (1-5 µm).

11.
J Chem Phys ; 135(15): 154306, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22029312

RESUMO

The time-resolved photodissociation dynamics of CH(3)I in the A-band has been studied theoretically using a wave packet model including four degrees of freedom, namely the C-I dissociation coordinate, the I-CH(3) bending mode, the CH(3) umbrella mode, and the C-H symmetric stretch mode. Clocking times and final product state distributions of the different dissociation (nonadiabatic) channels yielding spin-orbit ground and excited states of the I fragment and vibrationless and vibrationally excited (symmetric stretch ν(1) and umbrella ν(2) modes) CH(3) fragments have been obtained and compared with the results of femtosecond velocity map imaging experiments. The wave packet calculations are able to reproduce with very good agreement the experimental reaction times for the CH(3)(ν(1), ν(2))+I*((2)P(1/2)) dissociation channels with ν(1) = 0 and ν(2) = 0,1,2, and also for the channel CH(3)(ν(1) = 0, ν(2) = 0)+I((2)P(3/2)). However, the model fails to predict the experimental clocking times for the CH(3)(ν(1), ν(2))+I((2)P(3/2)) channels with (ν(1), ν(2)) = (0, 1), (0, 2), and (1, 0), that is, when the CH(3) fragment produced along with spin-orbit ground state I atoms is vibrationally excited. These results are similar to those previously obtained with a three-dimensional wave packet model, whose validity is discussed in the light of the results of the four-dimensional treatment. Possible explanations for the disagreements found between theory and experiment are also discussed.

12.
Phys Chem Chem Phys ; 13(29): 13295-304, 2011 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-21701757

RESUMO

This paper shows the results of combined experimental and theoretical work that have unravelled the mechanism of ultrafast ejection of a methyl group from a cluster, the methyl iodide dimer (CH(3)I)(2). Ab initio calculations have produced optimized geometries for the dimer and energy values and oscillator strengths for the excited states of the A band of (CH(3)I)(2). These calculations have allowed us to describe the blue shift that had been observed in the past in this band. This blue shift has been experimentally determined with higher precision than in all previously reported experiments, since it has been measured through its effect upon the kinetic energy release of the fragments using femtosecond velocity map imaging. Observations of the reaction branching ratio and of the angular nature of the fragment distribution indicate that two main changes occur in A-band absorption in the dimer with respect to the monomer: a substantial change in the relative absorption to different states of the band, and, more importantly, a more efficient non-adiabatic crossing between two of those states. Additionally, time resolved experiments have been performed on the system, obtaining snapshots of the dissociation process. The apparent retardation of more than 100 fs in the dissociation process of the dimer relative to the monomer has been assigned to a delay in the opening of the optical detection window associated with the resonant multiphoton ionization detection of the methyl fragment.

13.
J Chem Phys ; 131(13): 134311, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19814557

RESUMO

A nonresonant femtosecond laser pulse centered at 802 nm is used to probe the real time photodissociation dynamics of CH(3)I in the A-band at 267 nm. Using multiphoton ionization with this probe laser pulse and velocity map ion imaging of CH(3)(+), we have followed the time evolution of the translational energy and spatial anisotropy of the CH(3) fragment, which in turn has permitted to image the C-I bond breaking from the initial Franck-Condon region up to the final products along the reaction coordinate. Given the temporal width of our pump and probe laser pulses (approximately 80 fs), a mechanism is proposed by which transient species are probed by simultaneous absorption of pump and probe laser pulses through intermediate Rydberg and ionic states of CH(3)I while the pump and probe pulses overlap in time. This study shows how the combination of femtosecond multiphoton ionization and ion imaging techniques provides an ideal tool to resolve in time the different stages of the bond breaking event in a polyatomic molecule.

14.
Rev Sci Instrum ; 80(7): 073906, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19655964

RESUMO

A molecular beam epitaxy (MBE) facility has been built to enable in situ neutron scattering measurements during growth of epitaxial layers. While retaining the full capabilities of a research MBE chamber, this facility has been optimized for polarized neutron reflectometry measurements. Optimization includes a compact lightweight portable design, a neutron window, controllable magnetic field, deposition across a large 76 mm diameter sample with exceptional flux uniformity, and sample temperatures continuously controllable from 38 to 1375 K. A load lock chamber allows for sample insertion, storage of up to 4 samples, and docking with other facilities. The design and performance of this chamber are described here.

15.
An Pediatr (Barc) ; 71(2): 157-60, 2009 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-19410523

RESUMO

BACKGROUND: Transcutaneous bilirubinometers provide non-invasive data on newborn jaundice. The aim of this study is to evaluate whether the measurement of transcutaneous bilirubin can be correlated with serum bilirubin, and to find out whether gestational age, weight birth, race or hours of life affect those measurements. METHOD: Descriptive observational cross-sectional study on a sample of 65 simultaneous measurement of transcutaneous (TcB) and serum bilirubin (TSB). RESULTS: The correlation coefficient between both methods was 0.923. Race, gestational age and birth weight tends to not have any effects on the levels of transcutaneous bilirubin. CONCLUSION: Although bilirubinometer measurements tend to underestimate serum bilirubin, especially in patients with high levels, it is a useful technique as a screening tool in the evaluation of hyperbilirubinaemia.


Assuntos
Bilirrubina/sangue , Icterícia Neonatal/sangue , Estudos Transversais , Feminino , Testes Hematológicos/métodos , Humanos , Recém-Nascido , Masculino
16.
J Chem Phys ; 126(2): 021101, 2007 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-17228929

RESUMO

The reaction times of several well-defined channels of the C-I bond rupture of methyl iodide from the A band, which involves nonadiabatic dynamics yielding ground state I(2P3/2) and spin-orbit excited I*(2P1/2) and ground and vibrationally excited CH3 fragments, have been measured by a combination of a femtosecond laser pump-probe scheme and velocity map imaging techniques using resonant detection of ground state CH3 fragments. The reaction times found for the different channels studied are directly related with the nonadiabatic nature of this multidimensional photodissociation reaction.

17.
Mol Genet Genomics ; 272(2): 156-61, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15258852

RESUMO

The Alhambra (Alh) gene is the Drosophila homologue of the human AF10 gene. AF10 has been identified as a fusion partner of MLL, a human homologue of the fly gene trithorax, in infant leukemias. The endogenous function of human AF10 is not known, but may be vital to its role in acute leukemia. This prompted us to analyse Alh function. We describe here the genetic organisation of the Alh locus in D. melanogaster. We show that an independent lethal complementation group encoding a muscle protein (Mlp84B) is located within an Alh intron. We have already shown that the leucine zipper (LZ) domain of ALH activates several Polycomb group-responsive elements. We further demonstrate that the LZ domain on its own bears the Alh vital function, since it is necessary and sufficient for rescue of Alh mutant lethality. Finally, we demonstrate that, in contrast to a previous report, Alh does not affect position-effect variegation.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genes de Insetos , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição/genética , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/crescimento & desenvolvimento , Genes Letais , Teste de Complementação Genética , Humanos , Íntrons , Zíper de Leucina/genética , Zíper de Leucina/fisiologia , Leucemia/genética , Biologia Molecular , Proteínas do Tecido Nervoso/fisiologia , Especificidade da Espécie , Fatores de Transcrição/fisiologia
18.
Selección (Madr.) ; 12(2): 57-63, 2003. ilus
Artigo em Es | IBECS | ID: ibc-23987

RESUMO

En los últimos años la utilización de superficies deportivas de césped artificial se ha generalizado, especialmente en el ámbito del fútbol. La mejora en la calidad, la alta rentabilidad y las garantías de seguridad asociadas a los nuevos productos han sido las causas de este aumento en la producción y del desarrollo de nuevas generaciones de césped artificial. Este artículo presenta, en base al análisis de algunos estudios que relacionan la práctica deportiva sobre superficies de césped artificial con la generación de lesiones, y a la experiencia acumulada por el IBV (Instituto de Biomecánica de Valencia) durante el desarrollo de proyectos relacionados con éste tipo de superficies, los criterios normativos que regulan la calidad de un campo de césped artificial para la práctica del fútbol, así como el instrumental y la metodología empleada para su valoración (AU)


Assuntos
Humanos , Futebol/lesões , Fenômenos Biomecânicos , Ferimentos e Lesões/epidemiologia , Solo
19.
J Sports Sci ; 20(9): 671-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200918

RESUMO

Subjective tests based on information gathered using 'discomfort questionnaires' have been used widely in ergonomics. In this study, we used a similar method to examine the discomfort associated with the footwear worn in tennis matches. A sample of 146 tennis players from a population of approximately 4000 completed the questionnaire. We performed a descriptive analysis of the study variables. The associations between discomfort and pain and between discomfort and design errors were evaluated using cross-tabulation and chi-squared tests. We found that 9% of players considered their footwear to be uncomfortable, 23% considered it to be acceptable and 68% regarded it as comfortable. Six design errors were identified and five body areas were reported as experiencing discomfort due to the footwear. Factor analysis identified four factors related to discomfort and six design errors. Subsequent correlation analysis identified several relationships among these factors. There was a strong correlation (r = 0.187, P = 0.022) between plantar discomfort and incorrect arch support.


Assuntos
Fasciíte Plantar/etiologia , Dor/etiologia , Sapatos , Tênis , Adulto , Fenômenos Biomecânicos , Distribuição de Qui-Quadrado , Fasciíte Plantar/prevenção & controle , Feminino , Humanos , Masculino , Medição da Dor/métodos , Inquéritos e Questionários
20.
Genet Res ; 78(2): 137-48, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11732091

RESUMO

Members of the Polycomb group (Pc-G) and trithorax group (trx-G) of genes, as well as the enhancers of trx-G and Pc-G (ETP), function together to maintain segment identity during Drosophila development. In order to obtain new marked P mutations in these genes, we screened for dominant modifiers of the extra-sex-combs phenotype displayed by males mutant for the polyhomeotic (ph) gene, a member of the Pc-G group. Five P(lacW) insertions in four different genes were found to stably suppress ph: two are allelic to trithorax, one is the first allele specific to the Minute(2)21C gene, and the remaining two define new trx-G genes, toutatis (tou) in 48A and taranis (tara) in 89B10-13. tou is predicted to encode a 3109 amino acid sequence protein (TOU), which contains a TAM DNA-binding domain, a WAKZ motif, two PHD zinc fingers and a C-terminal bromodomain, and as such is likely to be involved in regulation of chromatin structure as a subunit of a novel chromatin remodelling complex. In a previous study, we found that insertion of a P(ph) transposable element containing ph regulatory sequences creates a high frequency of mutations modifying ph homeotic phenotypes. One such insertion enhanced the ph phenotype and we show that it is a new allele of UbcD1/eff, a gene encoding a ubiquitin-conjugating enzyme that is involved in telomere association and potentially in chromatin remodelling.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas de Drosophila , Drosophila/genética , Genes de Insetos/genética , Proteínas de Insetos/genética , Fatores de Transcrição , Animais , Linhagem Celular , Primers do DNA/química , Proteínas de Ligação a DNA/genética , Drosophila/embriologia , Feminino , Regulação da Expressão Gênica , Heterocromatina/metabolismo , Histona-Lisina N-Metiltransferase , Hibridização In Situ , Perna (Membro)/fisiologia , Masculino , Mutagênese Insercional , Nucleoproteínas , Fenótipo , Complexo Repressor Polycomb 1 , Complexo Repressor Polycomb 2 , Sequências Reguladoras de Ácido Nucleico , Proteínas Repressoras/genética
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