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1.
Phys Chem Chem Phys ; 26(26): 17991-17998, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38764355

RESUMEN

The photo-induced dynamics of o-nitrophenol, particularly its photolysis, has garnered significant scientific interest as a potential source of nitrous acid in the atmosphere. Although the photolysis products and preceding photo-induced electronic structure dynamics have been investigated extensively, the nuclear dynamics accompanying the non-radiative relaxation of o-nitrophenol on the ultrafast timescale, which include an intramolecular proton transfer step, have not been experimentally resolved. Herein, we present a direct observation of the ultrafast nuclear motions mediating photo-relaxation using ultrafast electron diffraction. This work spatiotemporally resolves the loss of planarity which enables access to a conical intersection between the first excited state and the ground state after the proton transfer step, on the femtosecond timescale and with sub-Angstrom resolution. Our observations, supported by ab initio multiple spawning simulations, provide new insights into the proton transfer mediated relaxation mechanism in o-nitrophenol.

2.
Ann Pharm Fr ; 81(3): 568-578, 2023 May.
Artículo en Francés | MEDLINE | ID: mdl-36513150

RESUMEN

This work presents the eight-month assessment of the mobile RFID (radio frequency identification) technology implementation for the management of sterile medical devices in an interventional cardiology department. Several indicators dedicated to stock management, organizational impact (within the pharmacy and the department) and economic impact were collected. The scope of MDS tracked by RFID was defined as well as the new supply circuit. In total, 297 (83%) references were managed by RFID. At eight months, the number of MDS units in stock has decreased by 35% and the number of overstocked references by more than 50%. The value of the inventory decreased by €30,196 (17%) in three months from an initial amount of €17,995. This decrease has been maintained at eight months. The average time spent by the pharmacy technician (PPH) was 66min/d. The paramedical team gained 180min/week. By integrating the cost of the equipment, the annual subscription and the PPH cost, the benefit is estimated at €9555 the first year (then €17,155 the following years). To conclude, RFID has allowed a significant reduction of the stock and its control over time while securing the supply circuit adjusted to the activity. The limits are the absence of interface between the dedicated software and the ordering software as well as the consequent time dedicated by the PPH to this new management mode.


Asunto(s)
Dispositivo de Identificación por Radiofrecuencia , Tecnología
3.
J Am Chem Soc ; 144(1): 446-453, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34928589

RESUMEN

The active forms of Au and Pt in CeO2-based catalysts for the water-gas shift (WGS) reaction are an issue that remains unclear, although it has been widely studied. On one hand, ionic species might be responsible for weakening the Ce-O bonds, thus increasing the oxygen mobility and WGS activity. On the other hand, the close contact of Au or Pt atoms with CeO2 oxygen vacancies at the metal-CeO2 interface might provide the active sites for an efficient reaction. In this work, using in situ X-ray absorption spectroscopy, we demonstrate that both Au and Pt remain unoxidized during the reaction. Remarkable differences involving the dynamics established by both species under WGS atmospheres were recognized. For the prereduced Pt catalyst, the increase of the conversion coincided with a restructuration of the Pt atoms into cuboctahedrical metallic particles without significant variations on the overall particle size. Contrary to the relatively static behavior of Pt0, Au0 nanoparticles exhibited a sequence of particle splitting and agglomeration while maintaining a zero oxidation state despite not being located in a metallic environment during the process. High WGS activity was obtained when Au atoms were surrounded by oxygen. The fact that Au preserves its unoxidized state indicates that the chemical interaction between Au and oxygen must be necessarily electrostatic and that such an electrostatic interaction is fundamental for a top performance in the WGS process.

4.
Phys Rev Lett ; 122(4): 042502, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30768318

RESUMEN

Even mass neutron-rich niobium isotopes are among the principal contributors to the reactor antineutrino energy spectrum. They are also among the most challenging to measure due to the refractory nature of niobium, and because they exhibit isomeric states lying very close in energy. The ß-intensity distributions of ^{100gs,100m}Nb and ^{102gs,102m}Nb ß decays have been determined using the total absorption γ-ray spectroscopy technique. The measurements were performed at the upgraded Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. Here, the double Penning trap system JYFLTRAP was employed to disentangle the ß decay of the isomeric states. The new data obtained in this challenging measurement have a large impact in antineutrino summation calculations. For the first time the discrepancy between the summation model and the reactor antineutrino measurements in the region of the shape distortion has been reduced.

5.
Lupus ; 28(13): 1566-1570, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31653191

RESUMEN

BACKGROUND: Intravenous immunoglobulin (IVIG) is prepared using purified human plasma. IVIG therapy has immunomodulatory effects on autoimmune diseases, including severe systemic lupus erythematosus (SLE). However, reports of its effects on large cohorts are scarce. METHODS: This single-center retrospective study included SLE patients treated with at least one IVIG cycle for SLE complications. Demographic data, indications, cycle numbers, and clinical improvement with IVIG were evaluated. SLE Disease Activity Index 2000 (SLEDAI-2K) scores were calculated at admission and after IVIG treatment in order to measure clinical improvement. RESULTS: Sixty-three SLE patients treated with IVIG (median age: 29 years; interquartile range 21-36 years; 84.13% female) were included, who received 2 g/kg IVIG for two to five days. Main indications were immune thrombocytopenia, hypogammaglobulinemia, infection during a SLE flare, bicytopenia, and immune hemolytic anemia. Seven patients received more than one IVIG cycle without severe adverse effects. Significant differences were found in SLEDAI-2K scores when the indications were immune thrombocytopenia and hypogammaglobulinemia, with a trend for hemolytic anemia. Patients with concomitant infection, myopathy, and gastrointestinal involvement showed a considerable reduction in their last SLEDAI-2K scores. Fourteen patients died during hospitalization, mainly due to septic shock and active SLE. CONCLUSIONS: IVIG showed adequate tolerance and effectiveness in selected severe SLE manifestations, mainly hematological involvement. It was useful for concomitant infection.


Asunto(s)
Inmunoglobulinas Intravenosas/administración & dosificación , Factores Inmunológicos/administración & dosificación , Lupus Eritematoso Sistémico/tratamiento farmacológico , Adulto , Estudios de Cohortes , Femenino , Humanos , Inmunoglobulinas Intravenosas/efectos adversos , Factores Inmunológicos/efectos adversos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
6.
FEMS Yeast Res ; 18(2)2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29370419

RESUMEN

Flor yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).


Asunto(s)
Biopelículas , Pared Celular/metabolismo , Proteínas Fúngicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Levaduras/fisiología , Pared Celular/genética , Fermentación , Proteínas Fúngicas/genética , Glicoproteínas de Membrana/genética , Mutación , Saccharomyces cerevisiae/fisiología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Vino
7.
Fish Shellfish Immunol ; 80: 458-466, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29859312

RESUMEN

The aim of this study was the assessment of preloaded feed pellets as a delivery system for plasmid DNA (pDNA), with the purpose of evaluating the potential administration of DNA vaccines orally in aquacultured fish. Pellets were made up by usual feed ingredients, which were mixed with chitosan nanoparticles entrapping a model plasmid (pCMVß) expressible in eukaryotic cells before being elaborated. The plasmid is characterized by the insertion of the reporter gene lacZ, encoding for the bacterial enzyme ß-galactosidase (ß-gal). The possible in vivo expression of the exogenous gene was measured in different fish tissues of gilthead sea bream (Sparus aurata) juveniles by two different procedures. On the one hand, the activity of the enzyme ß-gal was detected and quantified in muscle, liver and intestine; on the other, specific IgM against ß-gal antigen was titrated in blood samples. Intramuscular (i.m.) injection of equal amounts of plasmid was also carried out for the purpose of comparison with oral administration. The expression of the reporter gene was detected in fish tissues following both oral and i. m. administration of pDNA up to 60 days. However, organ distribution of the gene expression was more evident after oral (ß-gal activity measured in gut, liver and muscle) than after parenteral administration (restricted to adjacent muscle tissues). In agreement, specific IgM titration indicated that humoral immune response was more intense and sustained throughout the experimental period after oral than after i. m. delivery of equal amounts of pDNA. These results suggest that feed pellets containing chitosan nanoparticles might enable efficient oral delivery of pDNA, a fact that might imply valuable applications in terms of on-farm mass immunization purposes, especially with regard to DNA-based vaccines and small size fish, in which i. m. administration remains unfeasible.


Asunto(s)
Quitosano/administración & dosificación , ADN/administración & dosificación , Nanopartículas/administración & dosificación , Dorada/inmunología , Vacunas de ADN , Administración Oral , Alimentación Animal , Animales , Técnicas de Transferencia de Gen , Genes Reporteros , Inmunoglobulina M/sangre , Intestinos/enzimología , Hígado/enzimología , Músculos/enzimología , Plásmidos , Dorada/metabolismo , beta-Galactosidasa/inmunología , beta-Galactosidasa/metabolismo
8.
Fish Physiol Biochem ; 44(2): 661-677, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29354886

RESUMEN

Senegalese sole is one of the most promising fish species cultivated in the Southern European countries. This study was aimed at assessing the effects of microalgae biomass added to diets for Senegalese sole juveniles on fish growing and condition status. Three isoproteic (52%) and isolipidic (10%) were formulated containing 15% Tisochrysis lutea (TISO), Nannochloropsis gaditana (NAN), or Scenedesmus almeriensis (SCE) biomass, respectively. An experimental microalgae-free diet (CT) and a commercial diet (COM) were used as controls. Fish were fed at 3% of their body weight for 85 days. Final body weight of fish fed microalgae-supplemented diets did not differ from group fed CT diet. Fish-fed CT, TISO, NAN, and SCE showed higher growth performance and nutrient utilization figures than specimen-fed COM diet. The highest carcass lipid content was found in COM group (141 g kg-1), and no differences were observed in body protein content. Ash was significantly higher in TISO, NAN, and SCE groups compared to fish-fed CT. Muscle EPA and DHA contents were not modified owing to the different dietary treatments. The n3/n6 and EPA/DHA ratios in muscle were similar in all the experimental groups. The quantification of digestive proteolytic activities did not differ among experimental groups, although differences in the protease pattern in digestive extracts by zymography were revealed in those fish fed on COM diet. Both α-amylase activity in the intestinal lumen and leucine aminopeptidase in the intestinal tissue were significantly lower in COM fish. Specimens fed on SCE diet showed a higher leucine aminopeptidase activity associated to the intestinal tissue compared to NAN-fed fish (0.40 and 0.25 U g tissue-1, respectively). The ultrastructural study revealed that the dietary inclusion of algal biomass, especially T. lutea and N. gaditana, had a positive impact on the absorptive capacity of the intestinal mucosa. The highest values for the parameters microvilli length and microvilli absorption surface were observed in fish fed on NAN diet (1.99 µm and 45.93 µm2, respectively). Even though further studies aimed at optimizing commercial formulas for Senegalese sole are required prior to any large-scale practical utilization, the results obtained clearly suggest the potential of microalgae as dietary ingredients for this fish species.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Biomasa , Composición Corporal , Dieta/veterinaria , Peces Planos/fisiología , Microalgas/química , Alimentación Animal , Animales , Sistema Digestivo/metabolismo , Ácidos Grasos/metabolismo , Peces Planos/crecimiento & desarrollo , Liofilización
9.
Acta Psychiatr Scand ; 136(4): 389-399, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28865405

RESUMEN

OBJECTIVE: The interaction of single nucleotide polymorphisms with both distal and proximal environmental factors across the extended psychosis phenotype is understudied. This study examined (i) the interaction of relevant SNPs with both early-life adversity and proximal (momentary) stress on psychotic experiences (PEs) in an extended psychosis sample; and (ii) differences between early-psychosis and non-clinical groups for these interactions. METHODS: Two hundred and forty-two non-clinical and 96 early-psychosis participants were prompted randomly eight times daily for 1 week to complete assessments of current experiences, including PEs and stress. Participants also reported on childhood trauma and were genotyped for 10 SNPs on COMT, RGS4, BDNF, FKBP5, and OXTR genes. RESULTS: Unlike genetic variants, distal and proximal stressors were associated with PEs in both samples and were more strongly associated with PEs in the early-psychosis than in the non-clinical group. The RGS4 TA and FKBP5 CATT haplotypes interacted with distal stress, whereas the A allele of OXTR (rs2254298) interacted with proximal stress, increasing momentary levels of PEs in the early-psychosis group. No interactions emerged with COMT or BDNF variants. CONCLUSION: Individual differences in relevant stress-regulation systems interact with both distal and proximal psychosocial stressors in shaping the daily-life manifestation of PEs across the psychosis continuum.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles , Interacción Gen-Ambiente , Trastornos Psicóticos , Estrés Psicológico , Adulto , Estudios Transversales , Evaluación Ecológica Momentánea , Femenino , Humanos , Individualidad , Estudios Longitudinales , Masculino , Polimorfismo de Nucleótido Simple , Trastornos Psicóticos/etiología , Trastornos Psicóticos/genética , Trastornos Psicóticos/fisiopatología , Proteínas RGS/genética , Estrés Psicológico/etiología , Estrés Psicológico/genética , Estrés Psicológico/fisiopatología , Proteínas de Unión a Tacrolimus/genética , Adulto Joven
10.
Phys Rev Lett ; 117(1): 012501, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27419564

RESUMEN

The ß-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with ß-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb, and Bi in the mass region N≳126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the ß-decay strength distribution. This provides important constraints on global theoretical models currently used in r-process nucleosynthesis.

11.
Phys Rev Lett ; 115(6): 062502, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26296113

RESUMEN

Total absorption spectroscopy is used to investigate the ß-decay intensity to states above the neutron separation energy followed by γ-ray emission in (87,88)Br and (94)Rb. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large γ intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For (87)Br and (88)Br the γ branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich (94)Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n,γ) cross section that would have an impact on r process abundance calculations.

12.
Phys Rev Lett ; 115(10): 102503, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26382674

RESUMEN

The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.

13.
Med Intensiva ; 39(2): 90-6, 2015 Mar.
Artículo en Español | MEDLINE | ID: mdl-25238994

RESUMEN

OBJECTIVE: To determine the prevalence of contraindications to succinylcholine in patients admitted to the ICU. DESIGN: An observational study was carried out, describing the frequency of succinylcholine contraindication by stays, and associating the contraindications to population variables. SETTING: The adult general ICU of a reference hospital. PATIENTS: Clinical-surgical critically ill patients. Thirty consecutive days were analyzed. INTERVENTIONS: None. VARIABLES: Population variables: age, sex, APACHE II and SOFA scores, illness, days of hospitalization, mechanical ventilation and renal replacement therapy. CONTRAINDICATIONS: hyperkalemia, bedridden patients, rhabdomyolysis, muscle trauma, burns, infusion of neuromuscular blocking agents, acute renal failure, chronic renal failure, intraocular hypertension, intracranial hypertension, statin use, malignant hyperthermia, neuromuscular disease, spinal cord sectioning, bradycardia < 50 bpm, succinylcholine allergy, and pseudo-cholinesterase deficiency. RESULTS: A total of 102 patients were admitted, aged 60 ± 16 years (56.9% males), with the generation of 657 stays. Main diseases: elective heart surgery (33%), respiratory failure (22%) and sepsis (14%). We documented 466 stays (70.9%) with contraindications, particularly bedridden patients (n=140), neuromuscular blocking agents (n=101), acute renal failure (n=126), statin use (n=167), neuromuscular disease (n=159) and bradycardia (n=76). We recorded 74 stays (11.3%) at high risk of complications, secondary to hyperkalemic risk associated to receptor dysregulation. A high risk of complications was associated to advanced age, prolonged hospitalization, prolonged length of stay in the ICU, higher APACHE II and SOFA scores, mechanical ventilation and renal replacement therapy. CONCLUSION: Given the high prevalence of contraindications to succinylcholine observed, we discourage its use in patients admitted to the ICU.


Asunto(s)
Succinilcolina , Contraindicaciones , Estudios Transversales , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad
14.
Phys Chem Chem Phys ; 16(23): 11770-9, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24817114

RESUMEN

Progress in our understanding of ultrafast light-induced processes in molecules is best achieved through a close combination of experimental and theoretical approaches. Direct comparison is obtained if theory is able to directly reproduce experimental observables. Here, we present a joint approach comparing time-resolved photoelectron spectroscopy (TRPES) with ab initio multiple spawning (AIMS) simulations on the MS-MR-CASPT2 level of theory. We disentangle the relationship between two phenomena that dominate the immediate molecular response upon light absorption: a spectrally dependent delay of the photoelectron signal and an induction time prior to excited state depopulation in dynamics simulations. As a benchmark molecule, we have chosen hexamethylcyclopentadiene, which shows an unprecedentedly large spectral delay of (310 ± 20) fs in TRPES experiments. For the dynamics simulations, methyl groups were replaced by "hydrogen atoms" having mass 15 and TRPES spectra were calculated. These showed an induction time of (108 ± 10) fs which could directly be assigned to progress along a torsional mode leading to the intersection seam with the molecular ground state. In a stepladder-type approach, the close connection between the two phenomena could be elucidated, allowing for a comparison with other polyenes and supporting the general validity of this finding for their excited state dynamics. Thus, the combination of TRPES and AIMS proves to be a powerful tool for a thorough understanding of ultrafast excited state dynamics in polyenes.

15.
Med Intensiva ; 37(8): 519-74, 2013 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-23773859

RESUMEN

INTRODUCTION: Optimal management of sedation, analgesia and delirium offers comfort and security for the critical care patient, allows support measures to be applied more easily and enables an integral approach of medical care, at the same time that lowers the incidence of complications, wich translates in better patient outcomes. OBJECTIVE: To update the Guía de práctica clínica basada en la evidencia para el manejo de la sedoanalgesia en el paciente adulto críticamente enfermo published in Medicina Intensiva in 2007, and give recommendations for the management of sedation, analgesia, and delirium. METHODOLOGY: A group of 21 intensivists from 9 countries of the Federación Panamericana e Ibérica de Sociedades de Medicina Crítica y Terapia Intensiva, 3 of them also specialists in clinical epidemiology and methodology, gathered for the development of guidelines. Assessment of evidence quality and recommendations were made based on the Grading of Recommendations Assessment, Development and Evaluation system. Strength of recommendations was classified as 1=strong, or 2=weak, and quality of evidence as A=high, B=moderate, or C=low. Two authors searched the following databases: MEDLINE through PUBMED, The Cochrane Library and Literatura Latinoamericana y del Caribe en Ciencias de la Salud and retrieved pertinent information. Members assigned to the 11 sections of the guidelines, based on the literature review, formulated the recommendations, that were discussed in plenary sessions. Only those recommendations that achieved more than 80% of consensus were approved for the final document. The Colombian Association of Critical Medicine and Intensive Care (AMCI) supported the elaboration of this guidelines. RESULTS: Four hundred sixty-seven articles were included for review. An increase in number and quality of publications was observed. This allowed to generate 64 strong recommendations with high and moderate quality of evidence in contrast to the 28 recommendations of the previous edition. CONCLUSIONS: This Guidelines contains recommendations and suggestions based on the best evidence available for the management of sedation, analgesia and delirium of the critically ill patient, including a bundle of strategies that serves this purpose. We highlight the assessment of pain and agitation/sedation through validated scales, the use of opioids initially to apropiate analgesic control, associated with multimodal strategies in order to reduce opioide consumption; to promote the lowest level of sedation necessary avoiding over-sedation. Also, in case of the need of sedatives, choose the most appropiate for the patient needs, avoiding the use of benzodiazepines and identify risk factors for delirium, in order to prevent its occurrence, diagnose delirium and treat it with the most suitable pharmacological agent, whether it is haloperidol, atypical antipsychotics or dexmedetomidine, once again, avoiding the use of benzodiazepines and decreasing the use of opioids.


Asunto(s)
Analgesia , Sedación Consciente , Cuidados Críticos/normas , Enfermedad Crítica/terapia , Sedación Profunda , Algoritmos , Procedimientos Quirúrgicos Cardíacos , Delirio/terapia , Humanos , Fallo Hepático/terapia , Enfermedades del Sistema Nervioso/terapia , Cuidados Posoperatorios , Insuficiencia Renal/terapia , Respiración Artificial , Síndrome de Abstinencia a Sustancias/terapia , Desconexión del Ventilador
16.
Nat Commun ; 14(1): 2795, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37202402

RESUMEN

Electrocyclic reactions are characterized by the concerted formation and cleavage of both σ and π bonds through a cyclic structure. This structure is known as a pericyclic transition state for thermal reactions and a pericyclic minimum in the excited state for photochemical reactions. However, the structure of the pericyclic geometry has yet to be observed experimentally. We use a combination of ultrafast electron diffraction and excited state wavepacket simulations to image structural dynamics through the pericyclic minimum of a photochemical electrocyclic ring-opening reaction in the molecule α-terpinene. The structural motion into the pericyclic minimum is dominated by rehybridization of two carbon atoms, which is required for the transformation from two to three conjugated π bonds. The σ bond dissociation largely happens after internal conversion from the pericyclic minimum to the electronic ground state. These findings may be transferrable to electrocyclic reactions in general.

17.
Antimicrob Agents Chemother ; 56(4): 2119-21, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22290962

RESUMEN

During a ß-lactam resistance surveillance study, 12 IMP-18-positive Pseudomonas aeruginosa isolates belonging to 9 different pulsed-field gel electrophoresis groups were identified. In nine isolates, a class I integron with a novel gene array was identified that contained bla(IMP-18) and bla(OXA-224), while in two isolates the class I integron contained bla(IMP-18) and bla(OXA-2) but in a new arrangement. Our findings show the dissemination of two novel class I integrons in P. aeruginosa from different regions of Puerto Rico.


Asunto(s)
Integrones/genética , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/genética , beta-Lactamasas/genética , Adulto , Anciano , Anciano de 80 o más Años , Electroforesis en Gel de Campo Pulsado , Femenino , Humanos , Lactante , Masculino , Análisis por Micromatrices , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Pseudomonas aeruginosa/efectos de los fármacos , Puerto Rico
18.
Horm Metab Res ; 44(7): 533-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22344623

RESUMEN

Sexual dimorphism of GH secretion is unclear in humans. There is evidence that oral glucose (OG) administration initially decreases and subsequently stimulates GH secretion. Our aim was to study fasting GH concentrations and their response to OG administration in obese and healthy women and men, in order to elucidate the mechanism of sexual dimorphism of GH secretion and the possible contribution of ghrelin. We selected 33 women and 11 men as obese and healthy subjects. After an overnight fast, 75 g of oral glucose were administered; glucose, insulin, ghrelin, and PYY1-36 were obtained at baseline and during 300 min. Fasting GH (µg/l) was higher in women than men; 1.3 ± 0.3 vs. 0.2 ± 0.1, p=0.009, for women and men, respectively. The area under the curve between 0 and 150 min (AUC) of GH (µg/l · min) was higher in women than men; 98.2 ± 25.9 vs. 41.5 ± 28.6, p=0.002, for women and men, respectively. The AUC of total ghrelin (pg/ml · min, mean ± SEM) between 0 and 150 min was borderline and significantly higher in women than men; 128 562.3 ± 8 335.9 vs. 98 839.1 ± 7 668.6, p=0.069, for women and men, respectively. Several initial time points were higher in women than men. Glucose, insulin, and PYY1-36 were similar in women and men after OG. There were significant correlations between indices of post-oral glucose GH and ghrelin secretion. Fasting and initial GH secretion is higher in women than men, in contrast to peak and late GH secretion, which is similar in both cases. Sexual dimorphism in the regulation of GH secretion probably involves ghrelin.


Asunto(s)
Glucosa/administración & dosificación , Glucosa/farmacología , Hormona de Crecimiento Humana/metabolismo , Caracteres Sexuales , Administración Oral , Adulto , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Ayuno/sangre , Femenino , Ghrelina/sangre , Ghrelina/metabolismo , Prueba de Tolerancia a la Glucosa , Hormona de Crecimiento Humana/sangre , Humanos , Masculino
19.
Parasitology ; 139(8): 1045-53, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22716907

RESUMEN

A major issue for the proper understanding of the evolution of life-cycle histories is the regulation of voltinism and its variation. Diapause characteristics are known to regulate voltinism, but the underlying mechanisms are poorly understood. This paper studies diapause duration and voltinism variation in a haematophagous diptera parasitizing 2 sympatric hosts with very different breeding phenologies. We hypothesize that bivoltinism will be more frequent in carnid flies parasitizing an early breeding, multi-brooded species than in flies parasitizing a late breeder, single-brooded species. We obtained evidence of the co-occurrence of uni- and bivoltinism in both clutches of the multi-brooded Spotless starling (Sturnus unicolor) as well as in clutches of the single-brooded European roller (Coracias garrulus). Unexpectedly, the proportion of bivoltine flies was similar in both host species. A remarkable degree of host-parasite synchronization at the population level was found for bivoltine flies. Our findings reveal the facultative nature of diapause in Carnus. We discuss the influence of abiotic conditions and host availability on polymorphism in life-history cycles and the consequences both for the parasite and the host.


Asunto(s)
Enfermedades de las Aves/parasitología , Dípteros/fisiología , Infestaciones Ectoparasitarias/veterinaria , Reproducción/fisiología , Pájaros Cantores/parasitología , Estorninos/parasitología , Animales , Evolución Biológica , Infestaciones Ectoparasitarias/parasitología , Femenino , Aptitud Genética/fisiología , Interacciones Huésped-Parásitos , Estadios del Ciclo de Vida/fisiología , Masculino , Dinámica Poblacional , Pájaros Cantores/fisiología , España , Especificidad de la Especie , Estorninos/fisiología , Factores de Tiempo
20.
J Chem Phys ; 136(12): 124317, 2012 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-22462867

RESUMEN

Through a combined experimental and theoretical approach, we study the nonadiabatic dynamics of the prototypical ethylene (C(2)H(4)) molecule upon π → π(∗) excitation with 161 nm light. Using a novel experimental apparatus, we combine femtosecond pulses of vacuum ultraviolet and extreme ultraviolet (XUV) radiation with variable delay to perform time resolved photo-ion fragment spectroscopy. In this second part of a two part series, the XUV (17 eV < hν < 23 eV) probe pulses are sufficiently energetic to break the C-C bond in photoionization, or to photoionize the dissociation products of the vibrationally hot ground state. The experimental data is directly compared to excited state ab initio molecular dynamics simulations explicitly accounting for the probe step. Enhancements of the CH(2)(+) and CH(3)(+) photo-ion fragment yields, corresponding to molecules photoionized in ethylene (CH(2)CH(2)) and ethylidene (CH(3)CH) like geometries are observed within 100 fs after π → π(∗) excitation. Quantitative agreement between theory and experiment on the relative CH(2)(+) and CH(3)(+) yields provides experimental confirmation of the theoretical prediction of two distinct conical intersections and their branching ratio [H. Tao, B. G. Levine, and T. J. Martinez, J. Phys. Chem. A. 113, 13656 (2009)]. Evidence for fast, non-statistical, elimination of H(2) molecules and H atoms is observed in the time resolved H(2)(+) and H(+) signals.

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