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BACKGROUND: Optical coherence tomography can be used to assess retinal degeneration in multiple sclerosis (MS). Thinning of the retinal nerve fibre layer and macular thickness have been well characterized, but newer devices allow quantification of all retinal layers. OBJECTIVES: The objective of this study was to evaluate the thickness of the paramacular retina, peripapillary retinal nerve fibre layer, and deeper paramacular layers in MS patient subgroups, using state-of-the-art optical coherence tomography. METHODS: Using a Heidelberg Engineering Spectralis device, we performed paramacular volumetric retinal scans and circular peripapillary fibre-layer scans, manually segmenting different retinal layers into single horizontal foveal scans in 95 patients with definite MS (42 relapsing-remitting, 41 secondary progressive, 12 primary progressive), plus 91 age- and sex-matched controls. RESULTS: Even without a history of optic neuritis, all MS subgroups had significant thinning of the peripapillary retinal nerve fibre layer, the paramacular retinal thickness and the retinal ganglion cell- and inner plexiform layer. Only in primary progressive MS was the inner nuclear layer significantly reduced. CONCLUSIONS: Our findings indicate a primary retinal pathology involving the inner nuclear layer in primary progressive MS. Results in eyes without history of optic neuritis suggest possible subclinical episodes of optic neuritis or retrograde trans-synaptic degeneration of retinal ganglion cells and their axons.
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Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/patología , Retina/patología , Tomografía de Coherencia Óptica , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
All properties of molecules--from binding and excitation energies to their geometry--are determined by the highly correlated initial-state wavefunction of the electrons and nuclei. Details of these correlations can be revealed by studying the break-up of these systems into their constituents. The fragmentation might be initiated by the absorption of a single photon, by collision with a charged particle or by exposure to a strong laser pulse: if the interaction causing the excitation is sufficiently understood, the fragmentation process can then be used as a tool to investigate the bound initial state. The interaction and resulting fragment motions therefore pose formidable challenges to quantum theory. Here we report the coincident measurement of the momenta of both nuclei and both electrons from the single-photon-induced fragmentation of the deuterium molecule. The results reveal that the correlated motion of the electrons is strongly dependent on the inter-nuclear separation in the molecular ground state at the instant of photon absorption.
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Experiments with a process development unit for fast pyrolysis of biomass residues of 10kgh(-1) have been performed to quantify the impact of two different product recovery options. Wheat straw, miscanthus and scrap wood have been used as feedstock. A separate recovery of char increases the organic oil yield as compared to a combined recovery of char and organic condensate (OC). Furthermore, it allows for an alternative use of the byproduct char which represents an important product fraction for the high ash biomass residues under consideration. The char produced shows little advantage over its biomass precursor when considered as energy carrier due to its high ash content. Significant value can be added by demineralizing and activating the char. The potential to increase the economic feasibility of fast pyrolysis is shown by an assessment of the bioliq® process chain.
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Biomasa , Biotecnología/métodos , Carbón Orgánico/química , Temperatura , Carbono/análisis , Simulación por Computador , Triticum/química , Residuos , Madera/químicaRESUMEN
BACKGROUND: Neoadjuvant radiochemotherapy [n(R)CT] has become the standard of care in the multimodal therapy concept for patients with locally advanced esophageal cancer; however, optimal timing of surgery is not clearly defined. OBJECTIVES: The study analyzed whether the length of the interval between completion of n(R)CT and surgery can affect the postoperative outcome, tumor response and long-term survival. MATERIAL AND METHODS: A total of 106 patients with adenocarcinoma and squamous cell carcinoma of the esophagus, treated between 2006 and 2013, were included in this study. On the basis of the median time interval to surgery, patients were divided into two groups [group A ≤ 40 days (n = 54) and group B > 40 days (n = 52)] and compared concerning demographic data, preoperative risk scores, morbidity, outcome, tumor response and long-term survival. RESULTS: The groups were comparable in terms of demographics, preoperative condition of the patients, complications and outcome; however, group A showed a trend towards a higher mortality risk as preoperatively assessed by the physiological and operative severity score for the enumeration of mortality and morbidity in esophagogastric surgery patients (O-POSSUM) (p = 0.064) and group B showed a trend towards a higher rate of complete responders (p = 0.097). CONCLUSION: Concerning perioperative morbidity and mortality, delayed surgery after n(R)CT showed no benefit for the patient's outcome; however, the rate of complete tumor response was higher in patients with a time interval of more than 40 days, although this did not influence long-term survival or recurrence rates.
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Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/terapia , Esofagectomía , Terapia Neoadyuvante , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Terapia Combinada , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
Due to their health-beneficial ingredients the consumption of nuts can contribute to a healthy diet. The composition of hazelnuts, almonds, macadamia nuts, pistachios and walnuts regarding health-promoting and potentially harmful compounds was examined before and after roasting under different time and temperature conditions. Fatty acid compositions were not affected by roasting. Malondialdehyde increased with higher roasting temperatures (17-fold in walnuts). Levels of tocopherol isomers were reduced after roasting (α-T: 38%, ß-T: 40%, γ-T: 70%) and hydrophilic antioxidant capacity decreased significantly in hazelnuts (1.4-fold), macadamia nuts (1.7-fold) and walnuts (3.7-fold). Increasing roasting temperatures supported the formation of significant amounts of acrylamide only in almonds (1220 µg kg(-1)). In general, nuts roasted at low/middle temperatures (120-160°C) exhibited best sensory properties. Therefore, desired sensory quality along with a favourable healthy nut composition may be achieved by roasting over a low to medium temperature range.
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Acrilamida/metabolismo , Calor/uso terapéutico , Nueces/química , Tocoferoles/metabolismo , Antioxidantes , Ácidos GrasosRESUMEN
The utilisation of 31 sole carbon sources by bacterial communities of soil in the presence of increasing concentrations of Hg(II) was measured by a colour development assay. The assay was performed on Biolog microtitre plates (Ecoplates) in the presence of Hg(II) and compared to Hg(II)-free Ecoplates. Furthermore, community tolerance to Hg(II) was measured by colour development in microtitre plates supplemented with LB broth and by enumeration of colony-forming units on LB agar plates. Both microtitre plates supplemented with LB and LB agar plates contained increasing concentrations of Hg(II). The difference in substrate utilisation profile, as shown by growth on 31 different carbon substrates in the Ecoplates, suggested an adaptation of the soil community that correlated with the metal exposure level in the soil. Similarly, growth on microtitre plates supplemented with LB and plate-spreading data showed an increased community tolerance with increasing levels of mercury in the soil. Both the multi-function microtitre plate assay (Ecoplate) and the LB broth microtitre plate assay are suitable for evaluating the adaptation of the bacterial community in soil to a heavy metal pollutant.
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Adaptación Fisiológica , Bacterias/efectos de los fármacos , Mercurio/farmacología , Microbiología del Suelo , Contaminantes del Suelo/farmacología , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Técnicas Bacteriológicas/métodos , Carbono/metabolismo , Recuento de Colonia Microbiana , Medios de Cultivo , Ecosistema , Pruebas de Sensibilidad MicrobianaAsunto(s)
Adenocarcinoma Papilar/cirugía , Disnea/etiología , Edema/etiología , Cuello , Neoplasias Primarias Secundarias/diagnóstico por imagen , Neoplasias Primarias Secundarias/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Carcinoma Anaplásico de Tiroides/diagnóstico por imagen , Carcinoma Anaplásico de Tiroides/cirugía , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adenocarcinoma Papilar/diagnóstico por imagen , Adenocarcinoma Papilar/patología , Adenocarcinoma Papilar/radioterapia , Anciano de 80 o más Años , Terapia Combinada , Diagnóstico Diferencial , Disnea/diagnóstico por imagen , Edema/diagnóstico por imagen , Femenino , Humanos , Radioisótopos de Yodo/uso terapéutico , Escisión del Ganglio Linfático , Cuello/diagnóstico por imagen , Estadificación de Neoplasias , Neoplasias Primarias Secundarias/radioterapia , Complicaciones Posoperatorias/radioterapia , Reoperación , Carcinoma Anaplásico de Tiroides/radioterapia , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapiaRESUMEN
It is becoming increasingly essential to put into effect the processes of continuing education that will facilitate continuing access to education, adapt to political changes, technological advances and current situations, and reach all the population to be trained. In so doing, institutions must implement new educational methodologies that reduce costs and extend coverage. One of these methodologies is education at a distance, which is examined in this article. This type of approach uses methods and techniques for individual and team work (studies based on written and audiovisual materials which, along with back-up tutoring and practical equipment and instruments, make up an instructional package) and physical presence activities under direction and supervision; at the same time, it offers the possibility of a study schedule that complements the work day. It also facilitates the continuing education of in-service personnel and encourages to assume greater responsibility for their own instruction with a view to their own overall development and to the attainment of excellence in the performance of services. Education at a distance is an option for the training of manpower committed to the performance of health services, and it must be introduced into current educational programs slowly and by degrees. The Health Training Program for Central America and Panama (PASCAP) is preparing a methodological guide for the design of systems of education at a distance as a frame of reference that must be adapted to the specific characteristics and needs of each country and institution. These stages are, broadly, a conceptual framework and academic planning, academic production, teaching-learning, and evaluation.
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Educación Continua , Educación , Empleos en Salud/educación , Recursos Audiovisuales , Modelos Teóricos , Organización Panamericana de la Salud , Materiales de EnseñanzaRESUMEN
Plasmids control their copy number by limiting the amount of the initiator for DNA replication. The plasmid pUB110 initiator protein is termed RepU. Expression of the pUB110 repU gene is controlled by two antisense RNAs that interfere with repU mRNA translation. Genetic evidence suggests that Rep protein levels may be regulated by additional uncharacterized mechanisms. The repU gene product was radiolabeled and purified by monitoring the radioactive label. RepU overproduction was performed in cells containing the plasmid leading strand replication origin (dso), to allow for a putative inactivation of RepU. Polypeptides with apparent molecular masses of 42 (RepU*) and 39 (RepU) kDa were purified, both having the N-terminal sequence expected for the repU gene. The RepU/RepU* protein mixture bound specifically to dso. At low protein concentrations, about six RepU/RepU* protomers bound to the dso region. At higher concentrations, an extended nucleoprotein complex was formed. The promoter for the repU gene was localized downstream of the dso region. The results suggest that the extended RepU/RepU*-dso DNA complex interferes with repU promoter utilization. This provides an additional copy number control by limiting RepU concentration. Our results suggest that during replication the RepU protein might be converted into an inactive RepU-RepU* hetero-oligomer, further limiting the amount of RepU protein available for replication initiation.
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Proteínas Bacterianas/metabolismo , ADN Helicasas , Proteínas de Unión al ADN , Escherichia coli/genética , Factores de Iniciación de Péptidos/metabolismo , Plásmidos/metabolismo , Transactivadores/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Secuencia de Bases , Escherichia coli/metabolismo , Dosificación de Gen , Regulación Bacteriana de la Expresión Génica , Datos de Secuencia Molecular , Factores de Iniciación de Péptidos/genética , Plásmidos/genética , ARN Mensajero/metabolismo , Transactivadores/genéticaRESUMEN
To improve understanding of the relationship between the diversity and function of the soil ecosystem, we investigated the effect of two different disturbances on soil bacterial communities -- long-term exposure to the heavy metal mercury and transient exposure to the antibiotic tylosin. In the mercury-contaminated soil the diversity (Shannon index) was reduced as assessed from denaturing gradient gel electrophoresis (DGGE) of amplified 16S rDNA sequences from the soil community DNA and from colony morphology typing of the culturable bacterial population. However, analysis of the substrate utilization profiles did not reveal any differences in diversity. In the tylosin-treated soil, DGGE revealed a small difference in the diversity of 16S rDNA compared to the control soil, whereas analysis of the colony morphology typing or substrate utilization results did not reveal any differences in diversity. Soil function was also affected by mercury contamination. The lag time before soil respiration increased following addition of glucose or alfalfa substrate was longer in the mercury-contaminated soil than in the control soil. Moreover, it was markedly prolonged in mercury-contaminated soil subjected to heat treatment prior to substrate addition, thus indicating reduced resistance to a new disturbance in the mercury-contaminated soil as compared to the control soil. Tylosin treatment did not have any significant effect on any of the respiration parameters measured, either with or without prior heat treatment of the soil.
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Bacterias/efectos de los fármacos , Ecosistema , Microbiología del Suelo , Bacterias/genética , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Respiración de la Célula , Recuento de Colonia Microbiana , Dermatoglifia del ADN , ADN Bacteriano/genética , Mercurio/análisis , Mercurio/farmacología , ARN Ribosómico 16S/genética , Suelo/análisis , Contaminantes del Suelo/análisis , Contaminantes del Suelo/farmacología , Especificidad por Sustrato , Factores de Tiempo , Tilosina/análisis , Tilosina/farmacologíaRESUMEN
The effect of long-term exposure to mercury on the soil microbial community was investigated in soil from three different sites along a pollution gradient. The amount of total and bioavailable mercury was negatively correlated to the distance from the center of contamination. The size of the bacterial and protozoan populations was reduced in the most contaminated soil, whereas there was no significant difference in fungal biomass measured as chitinase activity. Based on the number of colony morphotypes, moreover, the culturable bacterial population was structurally less diverse and contained a higher proportion of resistant and fast-growing forms. The profiles of amplified 16S rDNA sequences obtained from community DNA by denaturating gradient gel electrophoresis (DGGE) also reflected the altered community structure and decreased diversity along the mercury gradient as expressed in terms of the number and abundance of bands. The functional potential of the microbial population measured as sole carbon source utilization by Ecoplates((R)) differed between the soils, but there was no change in the number of substrates utilized. The observed changes in the different soil microbial populations are probably a combination of both direct and indirect effects of the mercury contamination.