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Chemical communication in terrestrial vertebrates is often built on complex blends, where semiochemical and structural compounds may form an integrated functional unit. In lizards, many species have specialized epidermal glands whose secretions are waxy, homogeneous blends of lipids and proteins, both active in communication. The intimate co-occurrence of such compounds allows us to hypothesize that they should undergo a certain degree of covariation, considering both their semiochemical role and the support-to-lipid function hypothesized for the protein fraction. In order to assess the occurrence and level of protein-lipid covariation, we compared the composition and complexity of the two fractions in the femoral gland secretions of 36 lizard species, combining phylogenetically-informed analysis with tandem mass spectrometry. We found the composition and complexity of the two fractions to be strongly correlated. The composition of the protein fraction was mostly influenced by the relative proportion of cholestanol, provitamin D3, stigmasterol, and tocopherol, while the complexity of the protein pattern increased with that of lipids. Additionally, two identified proteins (carbonic anhydrase and protein disulfide isomerase) increased their concentration as provitamin D3 became more abundant. Although our approach does not allow us to decrypt the functional relations between the proteinaceous and lipid components, nor under the semiochemical or structural hypothesis, the finding that the proteins involved in this association were enzymes opens up to new perspectives about protein role: They may confer dynamic properties to the blend, making it able to compensate predictable variation of the environmental conditions. This may expand the view about proteins in the support-to-lipid hypothesis, from being a passive and inert component of the secretions to become an active and dynamic one, thus providing cues for future research.
(Italian) RiassuntoLa comunicazione chimica nei vertebrati terrestri è spesso costituita da miscele complesse, in cui composti semiochimici e strutturali possono formare un"unità funzionale integrata. Nelle lucertole, molte specie hanno ghiandole epidermiche specializzate le cui secrezioni sono miscele cerose e omogenee di lipidi e proteine, entrambe attive nella comunicazione. L"intima coesistenza di tali composti lascia ipotizzare che essi debbano subire un certo grado di co-variazione, sia considerando il loro ruolo semiochimico, sia la funzione di supporto ai lipidi ipotizzata per la frazione proteica. Per valutare la presenza e il livello di covariazione proteine-lipidi, abbiamo confrontato la composizione e la complessità delle due frazioni nelle secrezioni della ghiandola femorale di 36 specie di lucertole, combinando l"analisi filogenetica comparativa con la spettrometria di massa. Abbiamo riscontrato una forte correlazione tra la composizione e la complessità delle due frazioni. La composizione della frazione proteica è stata influenzata soprattutto dalla proporzione relativa di colestanolo, provitamina D3, stigmasterolo e tocoferolo, mentre la complessità del pattern proteico è aumentata con quella dei lipidi. Inoltre, due proteine identificate (anidrasi carbonica e disolfuro isomerasi) hanno aumentato la loro concentrazione al crescere dell'abbondanza della provitamina D3. Sebbene il nostro approccio non consenta di decifrare le relazioni funzionali tra le componenti proteiche e lipidiche, né secondo l"ipotesi semiochimica né secondo quella strutturale, la scoperta che le proteine coinvolte in questa associazione sono enzimi apre a nuove prospettive sul ruolo delle proteine stesse: esse potrebbero conferire proprietà dinamiche alla miscela, rendendola capace di compensare le prevedibili variazioni delle condizioni ambientali. Questo può ampliare la visione delle proteine nell'ipotesi che esse siano di supporto ai lipidi, da componente passiva e inerte delle secrezioni a componente attiva e dinamica, fornendo così spunti per ricerche future.
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In Italy, most of the cultivated walnuts belong to the Sorrento ecotype, and they are considered commercially valuable due to their specific organoleptic characteristics. The aim of this study is to evaluate and compare the morphological and compositional characteristics of walnuts sampled from 'Sorrento' trees cultivated in different locations in Campania and trees of both the 'Chandler' and 'Sorrento' varieties derived from the same location. The results demonstrated that 'Sorrento' and 'Chandler' walnuts have different biometric characteristics and a different fat content, with the highest fat content being found in the 'Sorrento' variety. Regarding the fatty acid (FA) composition, the content of monounsaturated and saturated fatty acids (MUFAs and SFAs) was highest in the 'Sorrento' variety (from 13 to 15% for MUFAs and from 11 to 13% for SFAs), while the polyunsaturated fatty acids (PUFAs) content was highest in the 'Chandler' variety (77%). The total phenolics content (TPC) was highest in the 'Sorrento' variety (from 910 to 1230 mg GAE/100 g), while no difference in γ-tocopherol content was found. Furthermore, the influence of walnut area cultivation was shown for fat content, FA composition and TPC. Therefore, both walnut varieties demonstrated good nutritional properties considering the PUFAs and γ-tocopherol content.
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The proof of concept of a new device, capable of determining in a few seconds the energy of clinical proton beams by measuring the time of flight (ToF) of protons, is presented. The prototype consists of two thin ultra fast silicon detector (UFSD) pads, aligned along the beam direction in a telescope configuration and readout by a digitizer. The method developed for extracting the energy at the isocenter from the measured ToF, validated by Monte Carlo simulations, and the procedure used to calibrate the system are also presented and discussed in detail. The prototype was tested at the Centro Nazionale di Adroterapia Oncologica (CNAO, Pavia, Italy), at several beam energies, covering the entire clinical range, and using different distances between the sensors. The measured beam energies were benchmarked against the nominal CNAO energy values, obtained during the commissioning of the centre from the measured ranges in water. Deviations of few hundreds of keV have been achieved for all considered proton beam energies for distances between the two sensors larger than 60 cm, indicating a sensitivity to the corresponding beam range in water smaller than the clinical tolerance of 1 mm. Moreover, few seconds of irradiation were necessary to collect the required statistics. These preliminary results indicate that a telescope of UFSDs could achieve in a short time the accuracy required for the clinical application and therefore encourage further investigations towards the improvement and the optimization of the present prototype.
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Terapia de Protones/métodos , Estudios de Factibilidad , Humanos , Método de Montecarlo , Terapia de Protones/instrumentación , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
The aim of this study was to determine the effect of the forage preservation method (silage vs. hay) on volatile compounds and sensory properties of a traditional Caciocavallo cheese during ripening. A brown-midrib sudangrass hybrid was cultivated on a 7-ha field and at harvesting it was half ensiled in plastic silo bags and half dried to hay. Forty-four lactating cows were equally allotted into 2 groups fed a isonitrogenous and isoenergetic total mixed ration containing as the sole forage either sorghum hay (H group) or sorghum silage (S group). Milk from the 2 groups was used to produce 3 batches/diet of Caciocavallo ripened for 30, 60, and 90 d. Milk yield and composition as well as cheese chemical and fatty acid composition were not markedly affected by the diet treatment and ripening time. By contrast, ripening induced increased levels of the appearance attribute "yellowness," along with the "overall flavor," the odor/flavor attributes "butter" and "hay," the "salty," "bitter," and "umami" tastes, and the texture attribute "oiliness," whereas the appearance attribute "uniformity" and the texture attribute "elasticity" were reduced. The silage-based diet induced higher perceived intensities of several attributes such as "yellowness"; "overall flavor"; "butter"; "grass" and "hay" odor/flavors; "salty," "bitter," and "umami" tastes; and "tenderness" and "oiliness" textures. In S cheese we also observed higher amounts of ketones and fatty acids. Conversely, H cheese showed the terpene α-pinene, which was not detected in S cheese, and a higher intensity of the appearance attribute "uniformity." These differences allowed the trained panel to discriminate the products, determined an increased consumer liking for 90-d ripened cheese, and tended to increase consumer liking for hay cheese.
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Alimentación Animal/análisis , Bovinos/fisiología , Queso/análisis , Ácidos Grasos/análisis , Leche/química , Sorghum , Animales , Dieta/veterinaria , Femenino , Lactancia , Leche/metabolismo , Hojas de la Planta , Ensilaje/análisis , Gusto , Factores de Tiempo , Compuestos Orgánicos Volátiles/análisisRESUMEN
CVD and associated metabolic diseases are linked to chronic inflammation, which can be modified by diet. The objective of the present study was to determine whether there is a difference in inflammatory markers, blood metabolic and lipid panels and lymphocyte gene expression in response to a high-fat dairy food challenge with or without milk fat globule membrane (MFGM). Participants consumed a dairy product-based meal containing whipping cream (WC) high in saturated fat with or without the addition of MFGM, following a 12 h fasting blood draw. Inflammatory markers including IL-6 and C-reactive protein, lipid and metabolic panels and lymphocyte gene expression fold changes were measured using multiplex assays, clinical laboratory services and TaqMan real-time RT-PCR, respectively. Fold changes in gene expression were determined using the Pfaffl method. Response variables were converted into incremental AUC, tested for differences, and corrected for multiple comparisons. The postprandial insulin response was significantly lower following the meal containing MFGM (P < 0·01). The gene encoding soluble epoxide hydrolase (EPHX2) was shown to be more up-regulated in the absence of MFGM (P = 0·009). Secondary analyses showed that participants with higher baseline cholesterol:HDL-cholesterol ratio (Chol:HDL) had a greater reduction in gene expression of cluster of differentiation 14 (CD14) and lymphotoxin ß receptor (LTBR) with the WC+MFGM meal. The protein and lipid composition of MFGM is thought to be anti-inflammatory. These exploratory analyses suggest that addition of MFGM to a high-saturated fat meal modifies postprandial insulin response and offers a protective role for those individuals with higher baseline Chol:HDL.
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Suplementos Dietéticos , Expresión Génica/efectos de los fármacos , Glucolípidos/metabolismo , Glicoproteínas/metabolismo , Secreción de Insulina/efectos de los fármacos , Comidas , Obesidad/metabolismo , Sobrepeso/metabolismo , Periodo Posprandial/efectos de los fármacos , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Colesterol/sangre , Citocinas/metabolismo , Productos Lácteos , Dieta , Epóxido Hidrolasas/genética , Epóxido Hidrolasas/metabolismo , Ayuno , Ácidos Grasos , Femenino , Glucolípidos/farmacología , Glicoproteínas/farmacología , Humanos , Insulina/sangre , Interleucina-6/metabolismo , Gotas Lipídicas , Masculino , Membranas/química , Síndrome Metabólico , Persona de Mediana Edad , Adulto JovenRESUMEN
PURPOSE: To describe a new system for scanned ion beam therapy, named RIDOS (Real-time Ion DOse planning and delivery System), which performs real time delivered dose verification integrating the information from a clinical beam monitoring system with a Graphic Processing Unit (GPU) based dose calculation in patient Computed Tomography. METHODS: A benchmarked dose computation algorithm for scanned ion beams has been parallelized and adapted to run on a GPU architecture. A workstation equipped with a NVIDIA GPU has been interfaced through a National Instruments PXI-crate with the dose delivery system of the Italian National Center of Oncological Hadrontherapy (CNAO) to receive in real-time the measured beam parameters. Data from a patient monitoring system are also collected to associate the respiratory phases with each spot during the delivery of the dose. Using both measured and planned spot properties, RIDOS evaluates during the few seconds of inter-spill time the cumulative delivered and prescribed dose distributions and compares them through a fast γ-index algorithm. RESULTS: The accuracy of the GPU-based algorithms was assessed against the CPU-based ones and the differences were found below 1. The cumulative planned and delivered doses are computed at the end of each spill in about 300â¯ms, while the dose comparison takes approximatively 400â¯ms. The whole operation provides the results before the next spill starts. CONCLUSIONS: RIDOS system is able to provide a fast computation of the delivered dose in the inter-spill time of the CNAO facility and allows to monitor online the dose deposition accuracy all along the treatment.
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Algoritmos , Iones/uso terapéutico , Sistemas en Línea , Dosificación Radioterapéutica , Computadores , Humanos , Respiración , Sincrotrones , Factores de TiempoRESUMEN
One major rationale for the application of heavy ion beams in tumour therapy is their increased relative biological effectiveness (RBE). The complex dependencies of the RBE on dose, biological endpoint, position in the field etc require the use of biophysical models in treatment planning and clinical analysis. This study aims to introduce a new software, named 'Survival', to facilitate the radiobiological computations needed in ion therapy. The simulation toolkit was written in C++ and it was developed with a modular architecture in order to easily incorporate different radiobiological models. The following models were successfully implemented: the local effect model (LEM, version I, II and III) and variants of the microdosimetric-kinetic model (MKM). Different numerical evaluation approaches were also implemented: Monte Carlo (MC) numerical methods and a set of faster analytical approximations. Among the possible applications, the toolkit was used to reproduce the RBE versus LET for different ions (proton, He, C, O, Ne) and different cell lines (CHO, HSG). Intercomparison between different models (LEM and MKM) and computational approaches (MC and fast approximations) were performed. The developed software could represent an important tool for the evaluation of the biological effectiveness of charged particles in ion beam therapy, in particular when coupled with treatment simulations. Its modular architecture facilitates benchmarking and inter-comparison between different models and evaluation approaches. The code is open source (GPL2 license) and available at https://github.com/batuff/Survival.
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Terapia de Protones/métodos , Radiobiología/métodos , Humanos , Cinética , Método de Montecarlo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Efectividad Biológica Relativa , Programas InformáticosRESUMEN
PURPOSE: The quality assurance (QA) procedures in particle therapy centers with active beam scanning make extensive use of films, which do not provide immediate results. The purpose of this work is to verify whether the 2D MatriXX detector by IBA Dosimetry has enough sensitivity to replace films in some of the measurements. METHODS: MatriXX is a commercial detector composed of 32×32 parallel plate ionization chambers designed for pre-treatment dose verification in conventional radiation therapy. The detector and GAFCHROMIC® films were exposed simultaneously to a 131.44MeV proton and a 221.45MeV/u carbon-ion therapeutic beam at the CNAO therapy center of Pavia - Italy, and the results were analyzed and compared. RESULTS: The sensitivity MatriXX on the beam position, beam width and field flatness was investigated. For the first two quantities, a method for correcting systematic uncertainties, dependent on the beam size, was developed allowing to achieve a position resolution equal to 230µm for carbon ions and less than 100µm for protons. The beam size and the field flatness measured using MatriXX were compared with the same quantities measured with the irradiated film, showing a good agreement. CONCLUSIONS: The results indicate that a 2D detector such as MatriXX can be used to measure several parameters of a scanned ion beam quickly and precisely and suggest that the QA would benefit from a new protocol where the MatriXX detector is added to the existing systems.
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Radioterapia de Iones Pesados/normas , Terapia de Protones/normas , Garantía de la Calidad de Atención de Salud , Radiometría/instrumentación , Estudios de Factibilidad , Dosificación RadioterapéuticaRESUMEN
PURPOSE: This paper describes the system for the dose delivery currently used at the Centro Nazionale di Adroterapia Oncologica (CNAO) for ion beam modulated scanning radiotherapy. METHODS: CNAO Foundation, Istituto Nazionale di Fisica Nucleare and University of Torino have designed, built, and commissioned a dose delivery system (DDS) to monitor and guide ion beams accelerated by a dedicated synchrotron and to distribute the dose with a full 3D scanning technique. Protons and carbon ions are provided for a wide range of energies in order to cover a sizable span of treatment depths. The target volume, segmented in several layers orthogonally to the beam direction, is irradiated by thousands of pencil beams which must be steered and held to the prescribed positions until the prescribed number of particles has been delivered. For the CNAO beam lines, these operations are performed by the DDS. The main components of this system are two independent beam monitoring detectors, called BOX1 and BOX2, interfaced with two control systems performing the tasks of real-time fast and slow control, and connected to the scanning magnets and the beam chopper. As a reaction to any condition leading to a potential hazard, a DDS interlock signal is sent to the patient interlock system which immediately stops the irradiation. The essential tasks and operations performed by the DDS are described following the data flow from the treatment planning system through the end of the treatment delivery. RESULTS: The ability of the DDS to guarantee a safe and accurate treatment was validated during the commissioning phase by means of checks of the charge collection efficiency, gain uniformity of the chambers, and 2D dose distribution homogeneity and stability. A high level of reliability and robustness has been proven by three years of system activity needing rarely more than regular maintenance and working with 100% uptime. Four identical and independent DDS devices have been tested showing comparable performances and are presently in use on the CNAO beam lines for clinical activity. CONCLUSIONS: The dose delivery system described in this paper is one among the few worldwide existing systems to operate ion beam for modulated scanning radiotherapy. At the time of writing, it has been used to treat more than 350 patients and it has proven to guide and control the therapeutic pencil beams reaching performances well above clinical requirements. In particular, in terms of dose accuracy and stability, daily quality assurance measurements have shown dose deviations always lower than the acceptance threshold of 5% and 2.5%, respectively.
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Iones/uso terapéutico , Radioterapia/instrumentación , Carbono/uso terapéutico , Diseño de Equipo , Humanos , Imanes , Terapia de Protones , Garantía de la Calidad de Atención de Salud , SincrotronesRESUMEN
PURPOSE: The first Italian hospital-based facility for hadrontherapy is the Centro Nazionale di Adroterapia Oncologica (CNAO) which started the clinical activity on September 2011 with protons beams. The control of the treatment is performed online by the Dose Delivery (DD) system which guides the whole treatment by measuring beam characteristics as number of delivered particles and beam position. The author will present the comparison between the required and delivered quantities. METHODS: The CNAO facility is based on a synchrotron designed to accelerate and deliver proton and carbon ion beams in the clinical ranges. Unlike most of the proton-therapy centres, the delivery technique adopted at CNAO is the "quasi-discrete" active scanning where dedicated magnets are used to drive a pencil beam through the target and the beam is normally not switched off during the transition between adjacent spots. These operations are performed by the DD system which, based on the treatment planning and the online analysis of dedicated beam monitor chambers, drives the scanning magnets. Spot by spot the DD records data which allow the comparison between the measured number of particles and position and the prescription. RESULTS: The data collected by the dose delivery during the treatments were analyzed in detail, each treatment consisting in more than 30 identical fractions. This allows checking the stability and the accuracy of the CNAO delivery over identical spot sequences. The comparison between the measured number of particles, the measured position of each spot, and the corresponding prescribed quantities will be presented in detail. Critical points will be discussed together with the proposed improvement of the system. CONCLUSIONS: The results confirm the good performance of the CNAO beam delivery obtained during the commissioning phase.
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A detector (MOPI) has been developed for the online monitoring of the beam at the Centro di AdroTerapia e Applicazioni Nucleari Avanzate (CATANA), where shallow tumours of the ocular region are treated with 62 MeV protons. At CATANA the beam is passively spread to match the tumour shape. The uniformity of the delivered dose depends on beam geometrical quantities which are checked before each treatment. However, beam instabilities might develop during the irradiation affecting the dose distribution. This paper reports on the use of the MOPI detector to measure the stability of the beam profile during the irradiation in the clinical practice. The results obtained in the treatment of 54 patients are also presented.
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Oftalmopatías/radioterapia , Laboratorios , Terapia de Protones , Radioterapia Asistida por Computador/métodos , HumanosRESUMEN
Quasidiscrete scanning is a delivery strategy for proton and ion beam therapy in which the beam is turned off when a slice is finished and a new energy must be set but not during the scanning between consecutive spots. Different scanning paths lead to different dose distributions due to the contribution of the unintended transit dose between spots. In this work an algorithm to optimize the scanning path for quasidiscrete scanned beams is presented. The classical simulated annealing algorithm is used. It is a heuristic algorithm frequently used in combinatorial optimization problems, which allows us to obtain nearly optimal solutions in acceptable running times. A study focused on the best choice of operational parameters on which the algorithm performance depends is presented. The convergence properties of the algorithm have been further improved by using the next-neighbor algorithm to generate the starting paths. Scanning paths for two clinical treatments have been optimized. The optimized paths are found to be shorter than the back-and-forth, top-to-bottom (zigzag) paths generally provided by the treatment planning systems. The gamma method has been applied to quantify the improvement achieved on the dose distribution. Results show a reduction of the transit dose when the optimized paths are used. The benefit is clear especially when the fluence per spot is low, as in the case of repainting. The minimization of the transit dose can potentially allow the use of higher beam intensities, thus decreasing the treatment time. The algorithm implemented for this work can optimize efficiently the scanning path of quasidiscrete scanned particle beams. Optimized scanning paths decrease the transit dose and lead to better dose distributions.
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Modelos Biológicos , Aceleradores de Partículas , Radiometría/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/métodos , Simulación por Computador , Humanos , Dosificación Radioterapéutica , Dispersión de RadiaciónRESUMEN
Rats were trained in an eight-arm radial maze to explore the apparatus in search of a food reward. After completion of the training phase, some animals were submitted to a hemicerebellectomy (HCbed group), while others were used as a control group. To study the effects of vestibular stimulation on the recall of ongoing working memory information, both groups were exposed to radial maze sessions: in the first session (no-rotation), animals were confined for 30 s to the fourth arm visited without being further manipulated; in the second session (rotation), the animals were again confined for 30 s to the fourth arm visited, while the apparatus was rotated five times around its vertical axis. The effects of these manipulations on successive visits to complete the task were assessed, as well as the solving time and kinds of errors made. Errors were significantly more frequent in the control animals during the rotation session; HCbed animals were unaffected by confinement alone or by vestibular stimulation, but showed a decreased search speed. It was concluded that vestibular input is required for an adequate functioning of the working memory system devoted to the formation and consolidation of spatial mnesic traces and that the amnesic effect due to vestibular stimulation is both anterograde and retrograde in nature.
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Aprendizaje por Laberinto/fisiología , Memoria a Corto Plazo/fisiología , Percepción Espacial/fisiología , Vestíbulo del Laberinto/fisiología , Animales , Cerebelo/fisiología , Conducta Exploratoria/fisiología , Alimentos , Ratas , Ratas Wistar , RecompensaRESUMEN
Mutagenic heterocyclic amines (HAs) are formed at low levels during cooking of meat and fish, and some of them are considered to be possible human carcinogens. The formation of HAs may be affected by the presence of synthetic or naturally occurring antioxidants. In the present study the effect of virgin olive oil (VOO) phenolic compounds, identified and quantified by LC-MS, on the formation of HAs in a model system was evaluated. An aqueous solution of creatinine, glucose, and glycine was heated in the presence of two samples of VOO differing only in the composition of phenolic compounds. The addition of VOO to the model system inhibited the formation of 2-amino-3-methylimidazo[4,5-f]quinoxaline (IQx), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) by between 30 and 50% compared with the control. Fresh-made olive oil, which contained a high amount of dihydroxyphenylethanol derivatives, inhibited HA formation more than a 1-year-old oil did. The inhibition of HA formation was also verified using phenolic compounds extracted from VOO.
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Aminas/metabolismo , Antioxidantes/farmacología , Fenoles/farmacología , Aceites de Plantas/metabolismo , Cromatografía Liquida , Compuestos Heterocíclicos/metabolismo , Reacción de Maillard , Modelos Químicos , Pruebas de Mutagenicidad , Mutágenos/metabolismo , Aceite de OlivaAsunto(s)
Radioisótopos de Galio , Neoplasias Renales/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Linfoma de Células B/diagnóstico por imagen , Neoplasias del Bazo/diagnóstico por imagen , Medronato de Tecnecio Tc 99m/análogos & derivados , Adulto , Femenino , Humanos , Ganglios Linfáticos/diagnóstico por imagen , CintigrafíaRESUMEN
The non-protein nitrogen (NPN) of samples of Parmigiano-Reggiano cheese ripened for 6 and 15 months was fractionated by ion-exchange chromatography on a Cu(2+)-Chelex column to separate oligopeptides from free amino acids. Peptide components were isolated by reversed-phase HPLC and identified by fast atom bombardment-mass spectrometry (FAB-MS). Only the NPN fraction of 6 month old cheese samples contained enough peptides to be further characterized. On the basis of FAB-MNS spectral results, 39 oligopeptides were identified, the main components being phosphopeptides. Two sets of both intact and partly dephosphorylated peptides, accounting for a total of 19 phosphopeptides, were formed by the hydrolysis of beta-casein and belonged to regions 1-20 and 6-28 of beta-casein. The formation and potential role of these peptides in cheese is discussed.
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Queso/análisis , Oligopéptidos/análisis , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Datos de Secuencia Molecular , Peso Molecular , Oligopéptidos/química , Fosfopéptidos/análisis , Fosfopéptidos/química , Espectrometría de Masa Bombardeada por Átomos VelocesRESUMEN
An aqueous extract ofRuta graveolens L. (250 g/liter) was tested for its allelopathic activity in vitro on radish germination and radicle growth in light and darkness. It caused a delay in the onset and a decrease in the rate of germination (40%) in the light. The photoinhibition of germination was accompanied by an inhibition of water uptake into the seed. Furthermore, the inhibition of radicle growth was slightly higher in the light than in darkness. Three potential allelochemicals, biologically active in the light, were isolated from the extract: 5-methoxypsoralen (5-MOP), 8-methoxypsoralen (8-MOP), and 4-hydroxy-coumarin at concentrations of 10(-4) M, 2×10(-4) M, and 0.4 ×10(-5) M respectively. At a concentration of 2×10(-4) M, 5-MOP was the most potent inhibitor, decreasing radish germination to 32% and radicle growth to 17% with respect to control. Microscopic observations of radish seeds treated with 5-MOP suggest that this substance changes the swelling of the seed coat and aleurone layer, which precedes radicle protrusion.
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A method to purify glial fibrillary acidic protein (GFAP) from mouse spinal cord is described, which permits the measurement of GFAP in the sciatic nerve of the twitcher mutant and control mouse. Cytoskeletal proteins from sciatic nerves and purified GFAP standards were electrophoresed on gel, transferred to nitrocellulose paper, and immunostained with anti-GFAP antibody. From the immunostained, 51,000-dalton band, we estimated about 200 ng GFAP per 50 micrograms of cytoskeletal protein in the twitcher sciatic nerve. The control nerve showed no detectable GFAP. Double-labeled fluorescence immunocytochemistry showed that in the brainstem of twitcher mutant, GFAP and vimentin were coexpressed in the majority of astrocytes.
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Tronco Encefálico/análisis , Proteína Ácida Fibrilar de la Glía/análisis , Ratones Mutantes Neurológicos/metabolismo , Nervio Ciático/análisis , Vimentina/análisis , Animales , Proteína Ácida Fibrilar de la Glía/aislamiento & purificación , Inmunohistoquímica , Ratones , Peso Molecular , Fracciones Subcelulares/análisisRESUMEN
The expression of glial fibrillary acidic protein (GFAP) was found to be markedly enhanced immunohistochemically and biochemically both in the central (CNS) and peripheral (PNS) nervous systems of the twitcher mutant, an authentic murine model of human globoid cell leukodystrophy. The astrocytes in the CNS, the unmyelinated Schwann cells in the sciatic nerve, and the satellite cells in the trigeminal ganglion stained heavily with anti-GFAP antiserum. These changes in GFAP expression occurred shortly before the initiation of demyelination and coincided chronologically and topographically with infiltration of macrophages, suggesting that the same or closely related factors trigger the infiltration of macrophages and activate expression of GFAP. Cytoskeletal protein preparations showed increases in GFAP as well as in vimentin in the brainstem, spinal cord, and sciatic nerve. These results demonstrate that at least two types of peripheral glia (the unmyelinated Schwann cell and the satellite cell), in addition to the astrocyte, respond to some pathologic stimuli with an increased expression of GFAP. However, two other GFAP-positive structures, the Bergmann and radial glia, showed no significant changes in their immunostaining.