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1.
J Phys Chem A ; 127(47): 9944-9958, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37964533

RESUMEN

Perylenediimide molecules constitute a family of chromophores that undergo singlet fission, a process in which an excited singlet state converts into lower energy triplets on two neighboring molecules, potentially increasing the efficiency of organic solar cells. Here, the nonorthogonal configuration interaction method is applied to study the effect of the different crystal packing of various perylenediimide derivatives on the relative energies of the singlet and triplet states, the intermolecular electronic couplings, and the relative rates for singlet fission. The analysis of the wave functions and electronic couplings reveals that charge transfer states play an important role in the singlet fission mechanism. Dimer conformations where the PDI molecules are at large displacements along the long axis and short on the short axis are posed as the most favorable for singlet fission. The role of the substituent at the imide group has been inspected concluding that, although it has no effect in the energies, for some conformations it significantly influences the electronic couplings, and therefore, replacing this substituent with hydrogen may introduce artifacts in the computational modeling of the PDI molecules.

2.
Phys Chem Chem Phys ; 24(19): 11931-11944, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35521680

RESUMEN

Two different approaches have been implemented to include the effect of dynamic electron correlation in the Non-Orthogonal Configuration Interaction for Fragments (NOCI-F) method. The first is based on shifting the diagonal matrix elements of the NOCI matrix, while the second incorporates the dynamic correlation explicitly in the fragment wave functions used to construct the many-electron basis functions of the NOCI. The two approaches are illustrated for the calculation of the electronic coupling relevant in singlet fission and the coupling of spin moments in organic radicals. Comparison of the calculated diabatic couplings, the NOCI energies and wave functions shows that dynamic electron correlation is not only efficiently but also effectively incorporated by the shifting approach and can largely affect the coupling between electronic states. Also, it brings the NOCI coupling of the spin moments in close agreement with benchmark calculations.

3.
Lett Appl Microbiol ; 75(3): 565-577, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34687563

RESUMEN

This study aimed to evaluate the inhibitory effects of phenolic-rich extracts from acerola (Malpighia emarginata D.C., PEA), cashew apple (Anacardium occidentale L., PEC) and mango (Mangifera indica L., PEM) by-products on distinct enterotoxigenic Escherichia coli (ETEC) strains. The capability of PEA and PEC of impairing various physiological functions of ETEC strains was investigated with multiparametric flow cytometry. Procyanidin B2 , myricetin and p-coumaric acid were the major phenolic compounds in PEA, PEC and PEM, respectively. PEA and PEC had lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (MIC: 31·25 mg ml-1 ; MBC: 62·5 mg ml-1 ) on ETEC strains than PEM (MIC and MIC: >1000 mg ml-1 ). PEA and PEC (15·6, 31·2, 62·5 mg ml-1 ) caused viable count reductions (P < 0·05) on ETEC strains after 24 h of exposure, notably the ≥3 log reductions caused by 62·5 mg ml-1 . The 24 h exposure of ETEC strains to PEA and PEC (31·2, 62·5 mg ml-1 ) led to high sizes of cell subpopulations with concomitant impairments in cell membrane polarization and permeability, as well as in enzymatic, respiratory and efflux activities. PEA and PEC are effective in inhibiting ETEC through a multi-target action mode with disturbance in different physiological functions.


Asunto(s)
Anacardium , Escherichia coli Enterotoxigénica , Infecciones por Escherichia coli , Mangifera , Fenoles/farmacología , Extractos Vegetales/farmacología
4.
BJOG ; 128(8): 1344-1352, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33540484

RESUMEN

OBJECTIVE: To validate the use of Seegene Allplex™ Vaginitis assay in the diagnosis of candidiasis, bacterial vaginosis (BV) and trichomoniasis. DESIGN: Cross-sectional, prospective study conducted in a single centre. SETTING: Outpatient clinic of a gynaecology department. POPULATION: Consecutive symptomatic and asymptomatic women (18-60 years of age). METHODS: Comparison of the assay test with the reference standards for the diagnosis of vaginitis (cultures for yeasts, Nugent for BV and nucleic acid amplification test for trichomoniasis). MAIN OUTCOME MEASURES: Performance of the investigational assay, in comparison with the reference standards for the diagnosis of the presence of Candida spp., Trichomonas vaginalis and BV. Secondary objectives are the evaluation of the performance of the test in postmenopausal women and in symptomatic women. RESULTS: A diagnosis of vaginitis was established in 14.0%. The global prevalences of BV, Candida spp. and T. vaginalis were 22.3%, 13.2% and 2.4%, respectively. The sensitivity and specificity of the assay test for those three causes of vaginitis were as follows: BV 91.7% and 86.6%; any Candida spp. 91.1% and 95.6%; Candida albicans 88.1% and 98.2%, non-albicans Candida 100% and 97.5%, and T. vaginalis 94.4 and 99.9%. The performance of the test was identical in the subgroup of women that reported vulvovaginal symptoms. The presence of multiple infections did not interfere with the performance of the test. CONCLUSIONS: The Seegene Allplex™ Vaginitis assay has an excellent performance in the diagnosis of the BV and presence of Candida; the results were good for trichomoniasis, but the study was underpowered for this outcome. TWEETABLE ABSTRACT: Seegene Allplex™ Vaginitis is an excellent option for screening and diagnosis of vaginitis.


Asunto(s)
Técnicas Microbiológicas/métodos , Reacción en Cadena de la Polimerasa Multiplex , Reacción en Cadena en Tiempo Real de la Polimerasa , Vaginitis/diagnóstico , Adolescente , Adulto , Candidiasis Vulvovaginal/diagnóstico , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Vaginitis por Trichomonas/diagnóstico , Vaginosis Bacteriana/diagnóstico , Adulto Joven
5.
BMC Health Serv Res ; 21(1): 1164, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34706718

RESUMEN

BACKGROUND: Social Prescribing (SP) is an innovative strategy to respond to the non-clinical health needs of the population. A Social Prescribing Local System (SPLS) can be defined as a set of joined community, health, and social organizations to foster SP-oriented activities. This study aimed to develop and assess the feasibility of an SPLS implemented in a Mediterranean country, to promote health and wellbeing and contribute to active and healthy aging. METHODS: A mixed-methods approach was followed, including three sequential components: 1) Cross-sectional online survey targeting health professionals (HP) working in a primary health care cluster, Portugal's southern region; 2) Pilot study implementing an on-the-job training program for HP, designed to meet identified training needs in the survey; 3) Focus group (FG) with the HP who participated in the pilot study, two individual interviews, with an elderly patient and a community provider for assessing the satisfaction with the pilot test. RESULTS: Sixty-five HP completed the survey; of these, 13 completed the theoretical part of the on-the-job training program; and six (out of these 13) completed the full program. Five HP participated in the FG, one patient and one community provider were interviewed. The surveyed HP perceived as facilitators to implement SP: an automatic system of notifications to prompt the use of SP, contribute to patient satisfaction, human and community resources' stability. The survey also highlighted barriers to SP implementation: length of appointments, shortage of human resources, data records confidentiality, low patient adherence rates, bureaucratic issues, time constraints, and financial costs. Participants were satisfied with the training. Identified SPLS implementation benefits were grouped into four dimensions (from the qualitative approach): gains for patients' health and wellbeing, support for the health services, sustainability of the community resources, and HP' professional satisfaction. CONCLUSIONS: Our study took the first steps towards the implementation of an SPLS. Findings reinforce that training HP in SP and on-the-job training seems feasible. This approach was well received and appears to represent a suitable and sustainable strategy. It can promote professional satisfaction, support health services, contribute to the stability of community resources, improve health and promote active and healthy aging.


Asunto(s)
Envejecimiento Saludable , Anciano , Estudios Transversales , Estudios de Factibilidad , Promoción de la Salud , Humanos , Proyectos Piloto
6.
Eur Ann Allergy Clin Immunol ; 53(3): 138-142, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33191719

RESUMEN

Summary: Introduction. Due to the Coronavirus disease 2019 (COVID-19) outbreak and the national emergency state, virtual visits were implemented as an alternative to in-person visits. With this study we aimed to establish asthma patients' general satisfaction with the quality of health care provided by virtual visits (phone or video calls). Materials and methods. A questionnaire (9 questions) was published on the Facebook page of the Portuguese Association of Asthmatics. It was available online for general self-reported asthmatic patients to answer during one month, starting on 11st May 2020. The survey only allowed one answer per registered user. Results. Fifty-five responses were obtained. Patients were satisfied with communication with providers (> 88%); nevertheless, one-half evaluated the virtual visit as inferior when compared to in-person visits. About one third attributed a classification of 6 or less (0-10 scale, 0 being the worst and 10 the best consultation possible), but still most of the patients would either recommend it or use this kind of medical visits in the future, even outside the actual pandemic context. Patients also referred some important limitations, as lack of physical examination and the fact that the medical visit was more impersonal. Only 27% had technical issues accessing virtual visits. Positive aspects were also named, such as virtual visits being practical and avoiding the need to move to the hospital. Discussion and conclusions. Our survey revealed that small changes could further increase patients' satisfaction, adherence and confidence in telemedicine. Although presenting some limitations, virtual visits seem to be generally well accepted by asthmatic patients and it might be a good alternative for in-person visits, at leastin such difficult times when social distancing is recommended.


Asunto(s)
Asma/terapia , COVID-19/prevención & control , Satisfacción del Paciente/estadística & datos numéricos , Telemedicina/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Portugal , Encuestas y Cuestionarios/estadística & datos numéricos
7.
Food Microbiol ; 90: 103449, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32336370

RESUMEN

The objective of this work was to assess the efficacy of sodium hypochlorite and peracetic acid for sanitization of Brazil nuts. To evaluate the natural microbiota of the nuts, the total bacteria and fungi as well as the Aspergillus section Flavi were counted. The moisture, water activity and the presence of aflatoxins was quantified. The response surface method was used to determine the influence of exposure time and sanitizers concentration on the reduction of Aspergillus nomius inoculated on the nuts. Microbiological, sensory and quantification analyzes of aflatoxins were performed under optimum conditions The evaluation of the initial contamination of the nuts, despite presenting high microbiological contamination, humidity and water activity, was not detected aflatoxins in any samples. In artificially inoculated samples, the response surface and the desirability function were obtained to determine the optimal point of use for each sanitizer. The nuts had high microbiological contamination, moisture content and water activity. Aflatoxins were not detected in any samples. The response surface and desirability function indicated the optimal sanitization conditions were 250 mg/L and 8.5 min and 140 mg/L and 15 min for sodium hypochlorite and peracetic acid, respectively. Reductions greater than 2 log CFU/g were obtained with sodium hypochlorite and of 1 log CFU/g for peracetic acid. In the tests performed with new Brazil nuts samples under the optimized conditions, reductions of less than 2 log CFU/g were obtained. Aflatoxin B1 was detected in one untreated sample (1.51 µg/kg), one sample treated with sodium hypochlorite (0.60 µg/kg) and two samples treated with peracetic acid (0.64 and 0.72 µg/kg). Demonstrating that the sanitizers in the concentrations used had no action on aflatoxins, despite being efficient for fungal control. The treatments did not cause an unacceptable sensorial impact on the samples.


Asunto(s)
Aspergillus/efectos de los fármacos , Bertholletia/microbiología , Desinfectantes/farmacología , Contaminación de Alimentos/prevención & control , Ácido Peracético/farmacología , Hipoclorito de Sodio/farmacología , Aflatoxinas/análisis , Microbiología de Alimentos
8.
Microb Pathog ; 130: 259-270, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30917922

RESUMEN

Fruits are among the main natural sources of phenolic compounds (PC). These compounds exert important antioxidant properties primarily associated with the presence of hydroxyl groups in their molecular structure. Additionally, the antibacterial effects of fruit phenolic-rich extracts or individual PC commonly found in fruits have been an emerging research focus in recent years. This review discusses by first time the available literature regarding the inhibitory effects of fruit PC on pathogenic bacteria, including not only their direct effects on bacterial growth and survival, but also their effects on virulence factors and antibiotic resistance, as well as the possible mechanism underlying these inhibitory properties. The results of the retrieved studies show overall that the antibacterial effects of fruit PC vary with the target bacteria, type of PC and length of exposure to these compounds. The type of solvent and procedures used for extraction and fruit cultivar also seem to influence the antibacterial effects of phenolic-rich fruit extracts. Fruit PC have shown wide-spectrum antibacterial properties besides being effective antibiotic resistance modifying agents in pathogenic bacteria and these effects have shown to be associated with interruption of efflux pump expression/function. Furthermore, fruit PC can cause down regulation of a variety of genes associated with virulence features in pathogenic bacteria. Results of available studies indicate the depolarization and alteration of membrane fluidity as mechanisms underlying the inhibition of pathogenic bacteria by fruit PC. These data reveal fruit PC have potential antimicrobial properties, which should be rationally exploited in solutions to control pathogenic bacteria.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Frutas/química , Fenoles/farmacología , Fitoquímicos/farmacología , Antibacterianos/aislamiento & purificación , Viabilidad Microbiana/efectos de los fármacos , Fenoles/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Virulencia/efectos de los fármacos
9.
Med Vet Entomol ; 32(3): 372-377, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29344968

RESUMEN

Sensitive techniques for the detection of Plasmodium (Aconoidasida: Plasmodiidae) sporozoites in field-collected malaria vectors are essential for the correct assessment of risk for malaria transmission. A real-time polymerase chain reaction (RT-PCR) protocol targeting Plasmodium mtDNA proved to be much more sensitive in detecting sporozoites in mosquitoes than the widely used enzyme-linked immunosorbent assay targeting Plasmodium circumsporozoite protein (CSP-ELISA). However, because of the relatively high costs associated with equipment and reagents, RT-PCRs are mostly used to assess the outcomes of experimental infections in the frame of research experiments, rather than in routine monitoring of mosquito infection in the field. The present authors developed a novel mtDNA-based nested PCR protocol, modified from a loop-mediated isothermal amplification (LAMP) assay for Plasmodium recognition in human blood samples, and compared its performance with that of routinely used CSP-ELISAs in field-collected Anopheles coluzzii (Diptera: Culicidae) samples. The nested PCR showed 1.4-fold higher sensitivity than the CSP-ELISA. However, nested PCR results obtained in two laboratories and in different replicates within the same laboratory were not 100% consistent, probably because the copy number of amplifiable Plasmodium mtDNA was close in some specimens to the threshold of nested PCR sensitivity. This implies that Plasmodium-positive specimens should be confirmed by a second nested PCR to avoid false positives. Overall, the results emphasize the need to use molecular approaches to obtain accurate estimates of the actual level of Plasmodium circulation within malaria vector populations.


Asunto(s)
Anopheles/parasitología , ADN Protozoario/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Plasmodium/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Animales , ADN Mitocondrial/análisis , Plasmodium/genética , Proteínas Protozoarias/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa/instrumentación
10.
Eur J Clin Microbiol Infect Dis ; 36(2): 379-386, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27812805

RESUMEN

The establishment of matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) in routine microbial identification boosted many developments towards high-throughput applications, including bacterial typing. However, results are still controversial for different bacterial species. We aim to evaluate the suitability of MALDI-TOF MS for typing clinically relevant multidrug resistant (MDR) Klebsiella pneumoniae subsp. pneumoniae clones using routine conditions and a previously validated chemometric analysis workflow. Mass spectra of 83 K. pneumoniae clinical isolates representing major human MDR clones [11 sequence types (STs), 22 PFGE-types] recovered in Portugal and Spain during outbreaks and non-outbreak situations (2003-2012) were obtained from cell extracts (CE) and intact cells (IC), and analysed with different chemometric tools. We observed a highly consistent peak pattern among isolates from different clones either with CE or IC, suggesting a high degree of conservation of biomolecules analysed (a large part corresponding to ribosomal proteins). Moreover, the low degree of agreement between MALDI-TOF MS and other methods (from 34.9 % to 43.4 % of correct assignments for CE and from 40.8 % to 70.1 % for IC) corroborates the low discriminatory potential of the technique at infraspecies level. Our results suggest a low discriminatory power of MALDI-TOF MS for clinically relevant MDR K. pneumoniae clones and highlight the need of developing tools for high-resolution typing in this species.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Klebsiella pneumoniae/química , Klebsiella pneumoniae/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Humanos , Infecciones por Klebsiella/microbiología , Portugal , España
11.
Gen Comp Endocrinol ; 250: 152-161, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28636888

RESUMEN

The neuropeptide galanin (Gal) is a putative factor regulating puberty onset and reproduction through its actions on the pituitary. The present study investigated the pituitary responsiveness to galanin and the patterns of galanin receptors (Galrs) expression throughout the reproductive cycle of two years old male European sea bass (Dicentrarchus labrax), an important aquaculture species. Quantitative analysis of pituitary and hypothalamus transcript expression of four galr subtypes revealed differential regulation according to the testicular developmental stage, with an overall decrease in expression from the immature stage to the mid-recrudescence stage. Incubation of pituitary cells with mammalian 1-29Gal peptide induced significant changes in cAMP concentration, with sensitivities that varied according to the testicular development stages. Furthermore 1-29Gal was able to stimulate both follicle stimulating hormone (Fsh) and luteinizing hormone (Lh) release from pituitary cell suspensions. The magnitude of the effects and effective concentrations varied according to reproductive stage, with generalized induction of Fsh and Lh release in animals sampled in January (full spermiation). The differential expression of galrs in pituitary and hypothalamus across the reproductive season, together with the differential effects of Gal on gonadotropins release in vitro strongly suggests the involvement of the galaninergic system in the regulation the hypothalamus-pituitary-gonad axis of male sea bass. This is to our knowledge the first clear evidence for the involvement of galanin in the regulation of reproduction in non-mammalian vertebrates.


Asunto(s)
Lubina/fisiología , Galanina/farmacología , Hipófisis/metabolismo , Reproducción/efectos de los fármacos , Animales , Lubina/genética , Colforsina/farmacología , AMP Cíclico/biosíntesis , Hormona Folículo Estimulante/metabolismo , Gametogénesis/efectos de los fármacos , Perfilación de la Expresión Génica , Gonadotropinas/farmacología , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Hormona Luteinizante/metabolismo , Masculino , Hipófisis/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Galanina/genética , Receptores de Galanina/metabolismo , Reproducción/fisiología
12.
Cir Pediatr ; 30(3): 152-155, 2017 Jul 20.
Artículo en Español | MEDLINE | ID: mdl-29043693

RESUMEN

OBJECTIVES: Post-appendectomy intra-abdominal abscesses are estimated to complicate up to 4.2% of acute non-perforated appendicitis and between 6.7% and 28% acute perforated appendicitis. This study was performed with the aim to review and characterize post-appendectomy intra-abdominal abscesses in our Pediatric Surgery department; to calculate their incidence and to evaluate the efficacy of the treatment modality. MATERIAL AND METHODS: A retrospective analysis of all patients, under 18 years and with the diagnosis of intra-abdominal abscess post-appendectomy, between January 2010 and December 2015 was performed, taking in account initial surgical approach, type of acute appendicitis, length of hospital stay and the treatment applied. Data were collected by reviewing clinical files. RESULTS: In a total of 1,340 appendectomies performed, there were 24 intra-abdominal abscesses identified (1.79%). Eight were feminine and sixteen masculine, and mean age was 11.9 years. In 52% of cases the diagnosis was made in the initial admission. Twelve have been submitted to laparoscopic appendectomy and the other 12 to open appendectomy. Of the 24 patients, only 4 needed a surgical re-intervention, which leaves medical treatment an 83.3% success rate. CONCLUSIONS: TThe incidence of intra-abdominal abscesses post-appendectomy, in the studied population, is what was expected and inferior to what's described in the literature. In our sample, conservative management for intra-abdominal abscesses post-appendectomy was successful in most of the cases, only 4 needing further surgical intervention.


OBJETIVOS: Se estima que la frecuencia en la que aparecen los abscesos intraabdominales postapendicectomía es de un 4,2% en las apendicitis agudas no perforadas y entre un 6,7 y 28% en las apendicitis agudas perforadas. Este estudio fue realizado con el objetivo de revisar los casos de abscesos intraabdominales en el postoperatorio de apendicectomía por apendicitis aguda en nuestro Servicio de Cirugía Pediátrica, calcular su incidencia y evaluar la eficacia del tratamiento implementado. MATERIAL Y METODO: Análisis retrospectivo de los pacientes, menores de 18 años y con diagnóstico de absceso intraabdominal postapendicectomía, entre enero de 2010 y diciembre de 2015, teniendo en cuenta el abordaje quirúrgico inicial, el tipo de apendicitis aguda, la duración del internamiento y el tipo de tratamiento efectuado. RESULTADOS: En un total de 1.340 apendicectomías realizadas se identificaron 24 abscesos intraabdominales (1,79%): ocho del sexo femenino y dieciséis del sexo masculino, con una media de edad de 11,9 años. En el 52% de los casos el diagnóstico fue realizado durante el ingreso inicial. Doce pacientes fueron sometidos a apendicectomía laparoscópica y 12 por laparotomía. De los 24 pacientes solamente 4 necesitaron de nuevo una intervención quirúrgica. Por lo tanto, el porcentaje de éxito del tratamiento médico fue de un 83,3%. CONCLUSIONES: La incidencia de abscesos intraabdominales postapendicectomía en la población estudiada está dentro de lo esperado e incluso es inferior a los valores mencionados en la literatura. En nuestra muestra con el tratamiento médico de los abscesos intraabdominales tuvimos muy buenos resultados en la mayoría de los casos, necesitando solo en 4 recurrir al tratamiento quirúrgico.


Asunto(s)
Absceso Abdominal/epidemiología , Apendicectomía/métodos , Apendicitis/cirugía , Complicaciones Posoperatorias/epidemiología , Absceso Abdominal/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Laparoscopía/métodos , Tiempo de Internación , Masculino , Estudios Retrospectivos
13.
Nanotechnology ; 27(33): 335301, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27378738

RESUMEN

The fabrication of segmented Ni/Cu nanowires (NWs), with tunable structural and magnetic properties, is reported. A potentiostatic electrodeposition method with a single electrolytic bath has been used to fabricate multisegmented Ni/Cu NWs inside a highly hexagonally ordered anodic nanoporous alumina membrane, with diameters of 50 nm and Ni segment lengths (L Ni) tuned from 10 nm up to 140 nm. The x-ray diffraction results evidenced a strong dependence of the Ni NWs crystallographic face-centered-cubic (fcc) texture along the [220] direction on the aspect ratio of the NWs. The magnetic behavior of the multisegmented Ni/Cu NW arrays, as a function of the magnetic field and temperature, is also studied and correlated with their structural and morphological properties. Micromagnetic simulations, together with the experimental results, showed a dominant antiferromagnetic coupling between Ni segments along the wire length for small low aspect-ratio magnetic segments. When increasing the Ni segments' length, the magnetic interactions between these along the wire became stronger, favouring a ferromagnetic coupling. The Curie temperature of the NWs was also found to strongly depend on the Ni magnetic segment length. Particularly the Curie temperature was found to be reduced 75 K for the 20 nm Ni segments, following the finite-size scaling relation with ξ 0 = 8.1 Å and γ = 0.48. These results emphasize the advantages of using a template assisted method to electrodeposit multilayer NWs, as it allows an easy tailor of the respective morphological, chemical, structural and magnetic properties.

14.
Phys Chem Chem Phys ; 18(4): 3223-33, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26744288

RESUMEN

A novel enzymatic platform for the sensing of H2O2 and glucose that uses L,L-diphenylalanine micro/nanostructures (FF-MNSs) as an enzyme support is shown. This platform is obtained by the self-assembly of poly(allylamine hydrochloride) (PAH), FF-MNSs, and microperoxidase-11 (MP11) anchored onto the peptide matrix, in two different crystal structures of FF-MNSs: hexagonal (P61) and orthorhombic (P22121). The electroactive area of the electrodes increases in the presence of FF-MNSs. We also demonstrate via theoretical calculations that the valence band energy of the orthorhombic structure allows it to be doped, similarly to p-type semiconductors, where PAH acts as a doping agent for the orthorhombic peptide structure, decreasing the band-gap by around 1 eV, which results in a smaller charge transfer resistance. These results are consistent with electrochemical impedance spectroscopy measurements, which further elucidate the role of the band structure of the orthorhombic FF-MNSs in the conductivity and electron transfer rates of the hybrid material. An effective communication between the electrode and the active site of a glucose oxidase enzyme through MP11-protein complexes occurs, paving the way for FF-MNSs in the orthorhombic phase for the future development of bioelectronics sensing devices.


Asunto(s)
Técnicas Biosensibles , Electrólitos/química , Péptidos/química , Glucosa/análisis , Peróxido de Hidrógeno/análisis , Microscopía Electrónica de Rastreo , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman
15.
Genet Mol Res ; 15(3)2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-27706605

RESUMEN

The enzymes 1,2-diacylglycerol cholinephosphotrans-ferase (CPT) and lysophosphatidylcholine acyltransferase (LPCAT) are important in lipid metabolism in soybean seeds. Thus, understand-ing the genes that encode these enzymes may enable their modification and aid the improvement of soybean oil quality. In soybean, the genes encoding these enzymes have not been completely described; there-fore, this study aimed to identify, characterize, and analyze the in silico expression of these genes in soybean. We identified two gene models encoding CPT and two gene models encoding LPCAT, one of which presented an alternative transcript. The sequences were positioned on the physical map of soybean and the promoter regions were analyzed. Cis-elements responsible for seed-specific expression and responses to biotic and abiotic stresses were identified. Virtual expression analysis of the gene models for CPT and LPCAT indicated that these genes are expressed under different stress conditions, in somatic embryos during differentiation, in immature seeds, root tissues, and calli. Putative ami-no acid sequences revealed the presence of transmembrane domains, and analysis of the cellular localization of these enzymes revealed they are located in the endoplasmic reticulum.


Asunto(s)
1-Acilglicerofosfocolina O-Aciltransferasa/genética , Diacilglicerol Colinafosfotransferasa/genética , Retículo Endoplásmico/enzimología , Glycine max/genética , Proteínas de Plantas/genética , 1-Acilglicerofosfocolina O-Aciltransferasa/química , 1-Acilglicerofosfocolina O-Aciltransferasa/metabolismo , Empalme Alternativo , Secuencia de Aminoácidos , Simulación por Computador , Diacilglicerol Colinafosfotransferasa/química , Diacilglicerol Colinafosfotransferasa/metabolismo , Retículo Endoplásmico/química , Retículo Endoplásmico/ultraestructura , Expresión Génica , Metabolismo de los Lípidos/genética , Modelos Genéticos , Mapeo Físico de Cromosoma , Células Vegetales/enzimología , Células Vegetales/ultraestructura , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/enzimología , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Semillas/citología , Semillas/enzimología , Alineación de Secuencia , Glycine max/citología , Glycine max/enzimología
16.
Cir Pediatr ; 29(3): 101-104, 2016 Jul 10.
Artículo en Español | MEDLINE | ID: mdl-28393503

RESUMEN

INTRODUCTION: Sialorrhea is a medical problem and can become a social issue, common in children with neurological disabilities. The bilateral submandibulectomy is one of the available treatment options for managing this pathology. AIM OF THE STUDY: The aim of this study is to evaluate the effectiveness of bilateral submandibulectomy in the management of sialorrhea in children with neurological disabilities through the parents' satisfaction grade. PATIENTS AND METHODS: We retrospectively analyzed 91 bilateral submandibulectomies for a period of time of 10 years (2004-2015). Data were taken from surgical records and patients files and were informatically processed. The severity grade before and after surgery was evaluated in line with the modified Teacher scale. Parental satisfaction was evaluated by applying a scale graded into five classes, according to the degree of sialorrhea severity in postoperative period. RESULTS: During the reporting period, 91 children underwent bilateral submandibulectomy in our center. Of these, 7 cases were excluded for lack of data. The average age of the children was 8,9 [± 3,5] years; 58,3% were male. The degree of preoperative sialorrhea severity was, in 52,4% of cases, level 4 (severe drooling), and in 28,6%, level 5 (very severe). The grade of parental satisfaction in postoperative period was ranked, in 73,8% of cases, between 81-100%. CONCLUSIONS: For children with drooling, a bilateral submandibulectomy emerges as an effective and efficient treatment, leaving parents with an extremely high satisfaction grade.


INTRODUCCION: La sialorrea es un problema médico y social, común en los niños con enfermedad neurológica. La submandibulectomía surge como una opción terapéutica posible y eficaz para esta patología. OBJETIVO: Evaluar la eficacia de la submandibulectomía bilateral, a través del grado de satisfacción de los padres de niños con sialorrea, sometidos a este procedimiento. MATERIAL Y METODOS: Análisis retrospectivo de 91 casos de niños sometidos a submandibulectomía bilateral durante 10 años (2004 a 2015). Los datos fueron obtenidos de los registros clínicos de cada paciente y tratados informáticamente. El grado de severidad en el pre y postoperatorio fue evaluado según la escala de Teacher modificada. La satisfacción de los padres fue evaluada a través de la aplicación de una escala que se divide en 5 clases, conforme el grado de severidad de sialorrea en el postoperatorio. RESULTADOS: Durante el periodo analizado, fueron sometidos a submandibulectomía bilateral 91 niños. De estos, fueron excluidos 7 casos por ausencia de datos. La edad media de los niños fue de 8,9 [± 3,5] años, siendo 58,3% del sexo masculino. El grado de severidad de sialorrea preoperatoria fue, en 52,4% de los casos, de nivel 4 (sialorrea grave) y, en 28,6%, de nivel 5 (muy grave). El grado de satisfacción de los padres fue alto o muy alto en el 94% de los casos. CONCLUSION: Para los niños con sialorrhea, la submandibulectomía surge como un tratamiento eficaz, que deja a los padres muy satisfechos y permite una mejor integración de los niños en la sociedad.


Asunto(s)
Padres/psicología , Sialorrea/cirugía , Glándula Submandibular/cirugía , Niño , Femenino , Humanos , Masculino , Satisfacción Personal , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
17.
Anal Biochem ; 479: 54-9, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25841673

RESUMEN

A major requirement to perform structural studies with membrane proteins is to define efficient reconstitution protocols that ensure a high incorporation degree and protein directionality and topology that mimics its in vivo conditions. For this kind of studies, protein reconstitution in membrane systems via a detergent-mediated pathway is usually successfully adopted because detergents are generally used in the initial isolation and purification of membrane proteins. This study reports OmpF reconstitution in preformed Escherichia coli liposomes followed by detection of its insertion by analyzing modifications on membrane structure by two different techniques: steady-state fluorescence anisotropy and dynamic light scattering. Another important issue is protein directionality. For OmpF, it is known that interaction with polyamines promotes channel blockage. In this work, the spermine-OmpF interaction was evaluated using surface plasmon resonance, and protein directionality was confirmed.


Asunto(s)
Escherichia coli/química , Lípidos/química , Liposomas/química , Porinas/química , Escherichia coli/metabolismo , Polarización de Fluorescencia , Metabolismo de los Lípidos , Liposomas/metabolismo , Porinas/metabolismo , Espermina/metabolismo
18.
Genet Mol Res ; 14(4): 15981-7, 2015 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-26662390

RESUMEN

Vigna unguiculata (L.) Walp (cowpea) is a food crop with high nutritional value that is cultivated throughout tropical and subtropical regions of the world. The main constraint on high productivity of cowpea is water deficit, caused by the long periods of drought that occur in these regions. The aim of the present study was to select elite cowpea genotypes with enhanced drought tolerance, by applying principal component analysis to 219 first-cycle progenies obtained in a recurrent selection program. The experimental design comprised a simple 15 x 15 lattice with 450 plots, each of two rows of 10 plants. Plants were grown under water-deficit conditions by applying a water depth of 205 mm representing one-half of that required by cowpea. Variables assessed were flowering, maturation, pod length, number and mass of beans/pod, mass of 100 beans, and productivity/plot. Ten elite cowpea genotypes were selected, in which principal components 1 and 2 encompassed variables related to yield (pod length, beans/pod, and productivity/plot) and life precocity (flowering and maturation), respectively.


Asunto(s)
Adaptación Biológica , Sequías , Fabaceae/genética , Fabaceae/metabolismo , Estudios de Asociación Genética , Carácter Cuantitativo Heredable , Selección Genética , Genotipo , Fenotipo , Análisis de Componente Principal
19.
Genet Mol Res ; 14(4): 18485-93, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26782496

RESUMEN

In this study, Lactococcus lactis was engineered to express mutated internalin A on its surface and to secrete large amounts of listeriolysin O (LLO) in order to improve its potential as a vehicle for DNA vaccination. Western blotting experiments demonstrated that the bacterium expressed LLO in both the cytoplasmic and extracellular compartments, with higher quantities found in the culture supernatants. A hemolytic assay showed that the recombinant strain secreted 250 ng active LLO/mg total protein. This mInlA/LLO-producing strain of L. lactis may be used as an alternative tool in DNA vaccination against a number of infectious diseases or in cancer therapy.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Toxinas Bacterianas/genética , Toxinas Bacterianas/inmunología , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/inmunología , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/inmunología , Lactococcus lactis/genética , Listeria monocytogenes/inmunología , Mutación , Proteínas Recombinantes , Vacunas Bacterianas , Membrana Celular/metabolismo , Expresión Génica , Hemólisis , Lactococcus lactis/metabolismo , Vacunación
20.
Clin Genet ; 86(1): 74-84, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23829326

RESUMEN

Marinesco-Sjögren syndrome (MSS; MIM 248800) is an autosomal recessive disorder characterized by congenital cerebellar ataxia, early cataracts, developmental delay, myopathy and short stature. Alterations in the gene SIL1 cause MSS in some patients with typical findings. In this study, molecular investigations including sequencing of the SIL1 gene, western blotting and microscopic investigations in fibroblast cultures were carried out in a cohort of 15 patients from 14 unrelated families, including the large, inbred family reported by Superneau et al., having the clinical features of MSS to provide insights into the pathophysiology of the disorder. A total of seven different mutations were found in eight of the patients from seven families. The mutations caused loss of the BIP-associated protein (BAP) protein in four patients by western blot. Novel clinical features such as dental abnormalities, iris coloboma, eczema and hormonal abnormalities were noticed in some patients, but there was no clear way to distinguish those with and without SIL1 mutations. Cultured fibroblasts contained numerous cytoplasmic inclusion bodies, similar to those identified in the brain of the whoozy mouse in five unrelated patients, three with and two without SIL1 mutations, suggesting some SIL1 negative patients share a common cellular pathogenesis with those who are SIL1 positive.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/genética , Fenotipo , Degeneraciones Espinocerebelosas/genética , Degeneraciones Espinocerebelosas/fisiopatología , Secuencia de Bases , Western Blotting , Preescolar , Cartilla de ADN/genética , Femenino , Genotipo , Humanos , Lactante , Masculino , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Mutación/genética , Análisis de Secuencia de ADN
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