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INTRODUCTION: In the care of heart failure patients, telemonitoring is receiving growing attention. The main purpose of this study was to determine the effect of continuous telemonitoring with an implantable loop recorder (ILR, Reveal XT), a novel strategy in the management of stable heart failure patients without a cardiac implantable device. Furthermore, little is known about the incidence of subclinical arrhythmias in this specific group of patients. MATERIALS AND METHODS: Stable heart failure patients, New York Heart Association Class II and III, without recent hospitalisation or upcoming intervention, were included. After implantation of the ILR there was regular contact with the research nurse on a pre-specified basis. Clinic visits and telephonic interviews were alternated for a minimum of 1 year. Parallel visits to their treating physician continued according to standard care. The treating physician was blinded for the ILR findings, accept for pre-specified, significant arrhythmic events. RESULTS: Thirty patients were included and followed for a median duration of 12 months. In 13 patients, data from the loop recorder led to therapeutic changes. One patient received a pacemaker. Eight patients developed atrial fibrillation, all subclinical, with a mean burden of 65.8⯱ 173.2â¯min/day. CONCLUSION: The use of an ILR could potentially impact patient management. Additional study is needed in different patient populations (e.â¯g. higher risk groups) to assess if an ILR could also impact on endpoints such as heart failure hospitalisation.
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Photoactive yellow protein (PYP) is a member of the xanthopsin family of eubacterial blue-light photoreceptors. On absorption of light, PYP enters a photocycle that ultimately transduces the energy contained in a light signal into an altered biological response. Nanosecond time-resolved x-ray crystallography was used to determine the structure of the short-lived, red-shifted, intermediate state denoted [pR], which develops within 1 nanosecond after photoelectronic excitation of the chromophore of PYP by absorption of light. The resulting structural model demonstrates that the [pR] state possesses the cis conformation of the 4-hydroxyl cinnamic thioester chromophore, and that the process of trans to cis isomerization is accompanied by the specific formation of new hydrogen bonds that replace those broken upon excitation of the chromophore. Regions of flexibility that compose the chromophore-binding pocket serve to lower the activation energy barrier between the dark state, denoted pG, and [pR], and help initiate entrance into the photocycle. Direct structural evidence is provided for the initial processes of transduction of light energy, which ultimately translate into a physiological signal.
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Proteínas Bacterianas/química , Luz , Fotorreceptores Microbianos , Conformación Proteica , Proteínas Bacterianas/metabolismo , Chromatiaceae/química , Cristalografía por Rayos X , Metabolismo Energético , Análisis de Fourier , Enlace de Hidrógeno , Isomerismo , Cinética , Modelos Moleculares , Transducción de SeñalRESUMEN
Spores of Bacillus subtilis were subjected to relatively mild heat treatments in distilled water and properties of these spores were studied. These spores had lost all or part of their dipicolinic acid (DPA) depending on the severity of the heat treatment. Even after relatively mild heat treatments these spore lost already a small but significant amount of DPA. When these spores were inoculated in nutrient medium-tryptone soy broth (TSA)-the non-lethally heated spores started to germinate. Results of classical optical density measurements showed that both phase darkening and subsequent outgrowth could be affected by sub-lethal heat. A study of single cells in TSB showed that lag times originating from exponentially growing cells followed a normal distribution, whereas lag times originating from spores followed a Weibull distribution. Besides classical optical density measurements were made to study the effect of previous heating on the kinetics of the first stages of germination. The germination kinetics could be described by the model as was proposed by Geeraerd et al. [Geeraerd, A.H., Herremans, C.H. and Van Impe, J.F., 2000. Structural model requirements to describe microbial inactivation during a mild heat treatment. International Journal of Food Microbiology 59, 185-209]. Two of the 4 parameters of the sigmoid model of Geeraerd were dependent on heating time and heating temperature, whereas the two other parameters were considered as independent of the heating conditions. Based on these observations, a secondary model could be developed that describes the combined effect of heating temperature and heating time on the kinetics of germination. To have more detailed information of the kinetics of germination samples incubated in TSB were tested at regular time intervals by flow cytometry. To that end the cells were stained with syto 9 to distinguish between the various germination stages. There was a qualitative agreement between the results of flow cytometry and those of optical density measurements, but there was a difference in quantitative terms. The results have shown that germination rate of spores is dependent on previous heating conditions both in the first stage when phase darkening occurs and also during the later stages of outgrowth when the phase dark spore develops to the vegetative cell.
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Bacillus subtilis/fisiología , Seguridad de Productos para el Consumidor , Modelos Biológicos , Ácidos Picolínicos/metabolismo , Esporas Bacterianas/crecimiento & desarrollo , Bacillus subtilis/crecimiento & desarrollo , Bacillus subtilis/metabolismo , Recuento de Colonia Microbiana/métodos , Citometría de Flujo , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Calor , Humanos , Cinética , Factores de TiempoRESUMEN
The rapid rise in microbiome and probiotic science has led to estimates of product creation and sales exceeding $50 billion within five years. However, many people do not have access to affordable products, and regulatory agencies have stifled progress. The objective of a discussion group at the 2017 meeting of the International Scientific Association for Probiotics and Prebiotics was to identify mechanisms to confer the benefits of probiotics to a larger portion of the world's population. Three initiatives, built around fermented food, were discussed with different methods of targeting populations that face enormous challenges of malnutrition, infectious disease, poverty and violent conflict. As new candidate probiotic strains emerge, and the market diversifies towards more personalised interventions, manufacturing processes will need to evolve. Information dissemination through scientific channels and social media is projected to provide consumers and healthcare providers with rapid access to clinical results, and to identify the nearest location of sites making new and affordable probiotic food and supplements. This rapid translation of science to individual well-being will not only expand the beneficiaries of probiotics, but also fuel new social enterprises and economic business models.
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Suplementos Dietéticos/economía , Probióticos/economía , Sector Público/economía , Suplementos Dietéticos/análisis , Alimentos Fermentados/análisis , Alimentos Fermentados/economía , Humanos , Modelos Económicos , Probióticos/análisisRESUMEN
The photoactive yellow protein (pyp) gene has been isolated from Rhodobacter sphaeroides by probing with a homologous PCR-product. A sequence analysis shows that this pyp gene encodes a 124 AA protein with 48% identity to the three known PYPs. Downstream from pyp, a number of adjacent open reading frames were identified, including a gene encoding a CoA-ligase homologue (pCL). This latter protein is proposed to be involved in PYP chromophore activation, required for attachment to the apoprotein. We have demonstrated the presence of the chromophoric group, previously identified in PYP from Ectothiorhodospira halophila as trans 4-hydroxy cinnamic acid, in phototrophically cultured R. sphaeroides cells by capillary zone electrophoresis. The basic structure of the chromophore binding pocket in PYP has been conserved, as shown by a 3D model of R. sphaeroides PYP, constructed by homology-based molecular modelling. In addition, this model shows that R. sphaeroides PYP contains a characteristic, positively charged patch.
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Proteínas Bacterianas , Ácidos Cumáricos/química , Modelos Moleculares , Fotorreceptores Microbianos , Conformación Proteica , Rhodobacter sphaeroides/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Electroforesis Capilar , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Propionatos , Alineación de SecuenciaRESUMEN
Analysis of the chromophore p-coumaric acid, extracted from the ground state and the long-lived blue-shifted photocycle intermediate of photoactive yellow protein, shows that the chromophore is reversibly converted from the trans to the cis configuration, while progressing through the photocycle. The detection of the trans and cis isomers was carried out by high performance capillary zone electrophoresis and further substantiated by 1H NMR spectroscopy. The data presented here establish the photo-isomerization of the vinyl double bond in the chromophore as the photochemical basis for the photocycle of photoactive yellow protein, a eubacterial photosensory protein. A similar isomerization process occurs in the structurally very different sensory rhodopsins, offering an explanation for the strong spectroscopic similarities between photoactive yellow protein and the sensory rhodopsins. This is the first demonstration of light-induced isomerization of a chromophore double bond as the photochemical basis for photosensing in the domain of Bacteria.
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Proteínas Bacterianas/química , Ácidos Cumáricos/química , Fotorreceptores Microbianos , Proteínas Bacterianas/efectos de la radiación , Chromatiaceae/química , Ácidos Cumáricos/efectos de la radiación , Electroforesis Capilar , Isomerismo , Espectroscopía de Resonancia Magnética , Fotoquímica , Propionatos , Protones , Rayos UltravioletaRESUMEN
Dynamic simulation technology is integrated with mass balance concepts and compartment-flux diagramming to create computer models that estimate contaminant export from watersheds over long and short-term futures under alternative simulated policies of watershed management. The Watershed Ecosystem Nutrient Dynamics (WEND) model, applied to developed watersheds with a mix of urban, agricultural, and forest land-uses, predicted phosphorus (P) export from three watersheds; a 275,000 ha dairy/urban watershed, a 77,000 ha poultry/urban watershed, and a 23,000 ha swine dominated watershed. Urban, agricultural, and forestry activities contribute to P export in different proportions. In all cases the P imports to the watershed exceed total export and P accumulates in watershed soils. Long-term future P export patterns are compared for several watershed management strategies that range from encouragement of rapid urban growth to aggressive environmental protection. The specific response of each watershed to imposed management is unique, but management strategies designed to reduce export of P over the long-term need to consider options that promote P input/output balance. Using this same approach, the Watershed Ecosystem Bacterial Dynamics (WEBD) model assesses the dynamics of bacterial populations in a small case-study watershed over an annual cycle as influenced by dairy farm management actions. WEND and WEBD models integrate the diversity of activities and stakeholders interested in the watershed and promote development of a more holistic understanding of watershed function. Model outputs are designed to assist watershed policy-makers, managers, and planners to explore potential future impacts of management/policy decisions.
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Modelos Teóricos , Fósforo/metabolismo , Microbiología del Agua , Contaminación del Agua/prevención & control , Agricultura , Animales , Bacterias , Bovinos , Ambiente , Agricultura Forestal , Fósforo/análisis , Formulación de Políticas , Dinámica Poblacional , Movimientos del Agua , Abastecimiento de AguaRESUMEN
The principles of mass balance, compartment-flux diagramming, and dynamic simulation modeling are integrated to create computer models that estimate phosphorus (P) export from large-scale watersheds over long-term futures. These Watershed Ecosystem Nutrient Dynamics (WEND) models are applied to a 275,000 ha dairy-documented watershed and a 77,000 ha poultry-dominated watershed in northeastern USA. Model predictions of present-day P export loads are consistent with monitoring data and estimates made using P export coefficients. For both watersheds P import exceeds P export and P is accumulating in the agricultural soils. Agricultural and urban activities are major contributors to P export from both watersheds. Continued urban growth will increase P export over time unless wastewater management is substantially enhanced and/or rates of urban growth are controlled. Agriculture cannot rely solely on the implementation of increasingly stringent conservation practices to reduce long-term P export but must consider options that promote P input/output balance. The WEND modeling process is a powerful tool to integrate the diversity of activities in watersheds into a holistic framework. Model outputs are suited to assist managers to explore long-term effects of overall watershed management strategies on P export in comparison to environmental and economic goals.
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Eutrofización , Modelos Teóricos , Fósforo/química , Contaminación del Agua/prevención & control , Agricultura , Ciudades , Simulación por Computador , Ecosistema , Humanos , Eliminación de Residuos , Movimientos del Agua , Contaminación del Agua/economíaRESUMEN
INTRODUCTION: Keratoacanthoma centrifugum marginatum is a rare variety of commonly isolated keratoacanthoma. The size of the lesions and prolonged evolution often raise therapeutic problems. CASE REPORT: A 63-year-old man presented with multiple keratoacanthoma centrifugum marginatum evolving for 6 months and predominating on the lower limbs. Because of the multiplicity and size of the lesions, the patient was treated at acitretine at the dose of 1 mg/kg/day for five months, leading to the regression of all the lesions. DISCUSSION: Keratoacanthoma centrifugum marginatum has rarely been reported in the literature. Our observation remains exceptional in the multiplicity and size of the lesions. The efficacy of retinoids, previously reported in the treatment of solitary giant keratoacanthoma, multiple keratoacanthoma and keratoacanthoma centrifugum marginatum, was demonstrated even in this handicapping form of keratoacanthoma.
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Queratoacantoma/patología , Dermatosis de la Pierna/patología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
In this study, the impact of a range of organic acids and structurally similar alcohols with three to six carbon backbones and increasing lipophilic character, were tested on the germination behavior of B. cereus ATCC 14579 spores. This approach allowed substantiating whether the effectivity of the various compounds was largely dictated by membrane interference or a classic weak acid acidification effect. The octanol-water partition coefficient (log P(oct/water)) ranges from 0.25/0.33 to 2.03/1.96 for propanol/undissociated propionic acid and hexanol/undissociated hexanoic acid, respectively. Performance of germination assays at neutral (pH7) and acidic conditions (pH5.5) allowed for a comparative analysis of the action of dissociated versus undissociated acids, and the presumed pH-independent effect of the corresponding alcohols. Germination assays, based on both continuously measured optical density and time-based plating experiments, and microscopic observations demonstrated the correlation between the lipophilic character of the selected compounds and their inhibiting effect on spore germination. Real-time fluorescence based assays showed that membrane integrity in dormant spores was maintained in the presence of the tested inhibitors. Lowering the critical concentration of inhibitors by a one-step washing procedure resulted in the onset of nutrient-induced germination, indicating the reversible nature of the inhibition process. Furthermore, blocking of nutrient-induced germination in the presence of inhibitory concentrations of selected lipophilic acids and corresponding alcohols was by-passed upon addition of Ca-dipicolinic acid, pointing to loss of signaling capacity in germinant receptor-mediated germination activity. These findings show that lipophilicity is an important determinant for the ability of the selected acids and corresponding alcohols to accumulate in the spore inner membrane and their ability to act as a germination-inhibitor.
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Microbiología de Alimentos , Ácidos/metabolismo , Alcoholes/metabolismo , Bacillus cereus/efectos de los fármacos , Bacillus cereus/fisiología , Concentración de Iones de Hidrógeno , Ácidos Picolínicos/metabolismo , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/fisiologíaRESUMEN
Transient neonatal pustular melanosis is a common, benign, but little known dermatosis in newborns. Diagnosis of transient neonatal pustular melanosis is made clinically, by the presence of vesiculopustular and pigmented macular skin lesions. This benign spontaneously regressive dermatosis should be distinguished from several serious infectious neonatal diseases. We report a case of transient neonatal pustular melanosis and discuss the nosologic problems and differential diagnosis of this entity.
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Vesícula/patología , Melanosis/patología , Humanos , Recién Nacido , Masculino , Remisión EspontáneaAsunto(s)
Linfoma de Células B/patología , Linfoma Cutáneo de Células T/patología , Linfoma de Células T/patología , Neoplasias Cutáneas/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biopsia , Causas de Muerte , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Ganglios Linfáticos/patología , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/radioterapia , Linfoma de Células T/tratamiento farmacológico , Linfoma Cutáneo de Células T/tratamiento farmacológico , Linfoma Cutáneo de Células T/radioterapia , Masculino , Persona de Mediana Edad , Micosis Fungoide/patología , Inducción de Remisión , Piel/patología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/radioterapiaRESUMEN
From cultures of the anoxygenic phototroph Halorhodospira halophila SL-1, an aerobic, gram-negative spirillum was isolated. This moderately halophilic, alkaliphilic bacterium was motile by means of a single polar flagellum. It is described here as Alkalispirillum mobile gen. nov., spec. nov. Phylogenetic analysis of the Alkalispirillum mobile 16S rRNA gene led to its classification in the gamma-subclass of the Proteobacteria, as it appears closely related to phototrophic purple sulfur bacteria of the genera Ectothiorhodospira and Halorhodospira. Surprisingly, A. mobile is an obligate aerobe. The organism grows optimally with a number of carboxylic acids (such as sodium acetate) as carbon source, at 2% (i.e. approximately 0.34 M) sodium chloride, at pH 9-10, and at temperatures ranging from 35 to 38 degrees C. The dominant cellular fatty acids of Alkalispirillum mobile are C12:0, C16:0, C18:1cis11, and C18:0; its G+C content is 66.2+/-0.5 mol%.
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Gammaproteobacteria/clasificación , Composición de Base , Ácidos Carboxílicos/metabolismo , Ácidos Grasos/análisis , Gammaproteobacteria/química , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Concentración de Iones de Hidrógeno , Concentración Osmolar , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio , TemperaturaRESUMEN
In nodules of Glycine max cv. Mandarin infected with a nod (+)fix(-) mutant of Rhizobium japonicum (RH 31-Marburg), lysis of bacteroids was observed 20 d after infection, but occurred in the region around the host cell nucleus, where lytic compartments were formed. Bacteroids, and peribacteroid membranes in other parts of the host cell remained stable until senescence (40d after infection). With two other nod(+) fix(-) mutants of R. japonicum either stable bacteroids and peribacteroid membranes were observed throughout the cell (strain 61-A-165) or a rapid degeneration of bacteroids without an apparent lysis (strain USDA 24) occurred. The size distribution of RH 31-Marburg-infected nodules exhibited only two maxima compared with four in wild-type nodules and nodule leghaemoglobin content was found to be reduced to about one half that of the wild type. The RH 31-Marburg-nodule type is discussed in relation to the stability of the bacteroids and the peribacteroid membrane system in soybean.
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Cutaneous metastases presenting as the first sign of cancer are rare. We present two cases of such metastases, one being a so-called sister Mary Joseph's nodule. The histologic findings revealed adenocarcinomas with features suggesting a primary gastrointestinal neoplasm.
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Adenocarcinoma/secundario , Neoplasias del Recto/patología , Neoplasias Cutáneas/secundario , Neoplasias Gástricas/patología , Adenocarcinoma/patología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias del Recto/diagnóstico , Neoplasias Cutáneas/patología , Neoplasias Gástricas/diagnósticoRESUMEN
BACKGROUND/AIMS: Intrinsic aging and photoaging may present different biomechanical properties. Dorsal and volar forearm skin is differently exposed to UV-light. The object was to derive a cutaneous extrinsic aging score (SEAS) representative of UV aging, i.e. the global photoaging corrected for intrinsic aging. METHODS: The Cutometer SM 474 was used for the measurement of skin mechanical properties. 86 healthy Caucasian women were studied. Dorsal and volar forearm skin was measured. RESULTS: Age related changes consisting of an overall increase in skin extensibility (Uf) and viscoelastic ratio (Uv/Ue) with decreased biologic elasticity (BE) was observed. Differentials in extensibility (Uf) and viscoelastic ration (Uv/Ue) between the volar and the dorsal test sites increase with age. CONCLUSIONS: Biomechanical parameters allow the evaluation of intrinsic aging in the concept of overall photoaging resulting from the combination of environmental damages superimposed to the intrinsic changes.
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Blue-light-induced repellent and demethylation responses, characteristic of behavioral adaptation, were observed in Rhodobacter sphaeroides. They were analyzed by computer-assisted motion analysis and through the release of volatile tritiated compounds from [methyl-(3)H]methionine-labeled cells, respectively. Increases in the stop frequency and the rate of methanol release were induced by exposure of cells to repellent light signals, such as an increase in blue- and a decrease in infrared-light intensity. At a lambda of >500 nm the amplitude of the methanol release response followed the absorbance spectrum of the photosynthetic pigments, suggesting that they function as photosensors for this response. In contrast to the previously reported motility response to a decrease in infrared light, the blue-light response reported here does not depend on the number of photosynthetic pigments per cell, suggesting that it is mediated by a separate sensor. Therefore, color discrimination in taxis responses in R. sphaeroides involves two photosensing systems: the photosynthetic pigments and an additional photosensor, responding to blue light. The signal generated by the former system could result in the migration of cells to a light climate beneficial for photosynthesis, while the blue-light system could allow cells to avoid too-high intensities of (harmful) blue light.
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Proteínas Bacterianas , Quimiotaxis/fisiología , Color , Metanol/metabolismo , Rhodobacter sphaeroides/fisiología , Rhodobacter sphaeroides/efectos de la radiación , Procesamiento de Imagen Asistido por Computador , Luz , Proteínas de la Membrana/metabolismo , Proteínas Quimiotácticas Aceptoras de Metilo , Modelos Biológicos , Fotosíntesis , Transducción de SeñalRESUMEN
The Kondo effect is usually connected with the interaction between a localized spin moment and itinerant electrons. This interaction leads to the formation of a narrow resonance at the Fermi level, which is called the Abrikosov-Suhl or Kondo resonance. Scanning tunnelling microscopy is an ideal technique for real-space investigations of complicated electronic structures and many-body phenomena, such as the formation of the Kondo resonance or d-wave pairing in high-T(c) superconductors. Theory has predicted that similar, Kondo-like many-electron resonances are possible for scattering centres with orbital instead of spin degrees of freedom--the quadruple momenta in uranium-based compounds or two-level systems in metallic glasses are examples of such 'pseudo-Kondo' scattering centres. Here we present evidence for the orbital Kondo resonance on a transition-metal surface. Investigations of an atomically clean Cr(001) surface at low temperature using scanning tunnelling microscopy reveal a very narrow resonance at 26 meV above the Fermi level, and enable us to visualize the orbital character of the corresponding state. The experimental data, together with many-body calculations, demonstrate that the observed resonance is an orbital Kondo resonance formed by two degenerate d(xz), d(yz) surface states.