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1.
Ecotoxicol Environ Saf ; 145: 83-89, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28708985

RESUMEN

The effects of cadmium and lead were investigated in Cynara cardunculus L. Plant uptake by root and shoot, changes in cell ultrastructure and photosynthetic efficiency, photosynthetic key protein levels, as well as regulation of stress-induced Hsp70 were examined. Cynara cardunculus accumulated Cd and Pb in their tissue, with a different trend for the two metals. The prompt translocation of Cd to the shoot may justify the ultrastructural injuries, especially observed in chloroplasts. However, Cd- treated plants did not show any decline in photochemistry; it is likely that Cd in shoot tissue triggers defense mechanisms, increasing the level of proteins involved in photosynthesis (i.e., Rubisco and D1 increased 7 and 4.5 fold respectively) as a compensatory response to neutralize chloroplast damage. The accumulation of Pb mainly in root, can explain the increase in Hsp70 level (23 folds) in this tissue. Pb reached the shoots, even at low amounts, causing an overall significant change in some photochemical parameters (QY and NPQ decreases and increases of 25%, respectively). The results suggest a higher sensitivity of C. cardunculus to Pb than Cd, although maximal photochemical efficiency suggests that this species seems to tolerate Pb and Cd and hence, it is a suitable candidate for phytoremediation.


Asunto(s)
Cadmio/toxicidad , Cynara/efectos de los fármacos , Plomo/toxicidad , Fotosíntesis/efectos de los fármacos , Proteínas de Plantas/metabolismo , Contaminantes del Suelo/toxicidad , Biodegradación Ambiental , Cadmio/metabolismo , Cloroplastos/efectos de los fármacos , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Cynara/metabolismo , Cynara/ultraestructura , Plomo/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Contaminantes del Suelo/metabolismo
2.
J Hazard Mater ; 381: 120949, 2020 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-31387076

RESUMEN

In this study we evaluated a new type of passive air sampler, the "mossphere" device, filled with a Sphagnum palustre clone. For this purpose, we compared the atmospheric levels of polyaromatic hydrocarbons (PAHs) collected using this device and those collected in conventional bulk deposition and particulate matter (PM10) samplers. All three types of samplers were exposed at 10 sites affected by different levels of pollution and located in two different climate zones. The bulk deposition/ mossphere comparison yielded a greater number of significant regressions with higher coefficients of determination than the PM10/ mossphere comparison. No significant regressions were observed for 3-ring PAHs in either comparison. The mosspheres explain ca. 50% of the variability of the concentrations of 4-, 5- and 6-ring PAHs and total PAHs detected in PM10 and ca. 70% of the corresponding concentrations detected in the bulk deposition. The use of the Sphagnum clone enables standardization of the set-up, thus making the mossphere device a good sampling tool for monitoring 4-, 5- and 6-ring and total PAHs, especially those associated with bulk deposition. The findings indicate the potential usefulness of this innovative technology for mapping PAH levels.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/instrumentación , Hidrocarburos Policíclicos Aromáticos/análisis , Sphagnopsida , Contaminación del Aire/análisis
3.
Environ Pollut ; 249: 566-572, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30933753

RESUMEN

This study investigated by the moss-bag approach the pattern of air dispersed elements in 12 coupled indoor/outdoor exposure sites, all located in urban and rural residential areas. The aims were to discriminate indoor vs. outdoor element composition in coupled exposure sites and find possible relation between moss elemental profile and specific characteristics of each exposure site. Elements were considered enriched when in 60% of the sites, post-exposure concentration exceeded pre-exposure concentration plus two folds the standard deviation. Of the 53 analyzed elements, 15 (As, B, Ca, Co, Cr, Cu, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, Zn) were enriched in moss exposed outdoor, whereas a subset of 7 elements (As, B, Cr, Mo, Ni, Se, V) were enriched also in indoor moss samples. The cluster analysis of the sites based on all elements, clearly separated samples in two groups corresponding to mosses exposed indoor and outdoor, with the latter generally exceeding the first. Among outdoor sites, urban were most impacted than rural; whereas other factors (e.g., heating and cooking systems, building material, residence time and family life style) could affect element profile of indoor environments. Based on the indoor/outdoor ratio, As derived from outdoor and indoor sources, B, Mo and Se were enriched mostly in outdoor sites; Ni, Cr and V were specifically enriched in most indoor samples, supporting the presence of indoor emitting sources for these elements. A PCA of all indoor sites based on enriched elements and site characteristics showed that traffic affected indoor pollution in urban areas. The moss bag approach provided useful information for a global assessment of human exposure.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Briófitas/química , Elementos Químicos , Monitoreo del Ambiente/métodos , Calefacción , Vivienda , Humanos
4.
Chemosphere ; 205: 1-7, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29677573

RESUMEN

Mosses are well known as biomonitors of fresh water for metal pollutants, but no studies were reported so far about their ability to intercept plastic particles, although this kind of pollution has become an urgent issue worldwide. In the present work, the interaction between the moss Sphagnum palustre L. cultured in vitro and polystyrene nanoparticles (NPs) was studied for the first time in a laboratory experiment, in the view of using moss transplants for detecting microplastics in fresh water environments. The ability of S. palustre to intercept and retain polystyrene, and the effects of vitality and post-exposure washing on NP retention by moss were tested. Fluorescence microscope observations showed that polystyrene NPs were retained by moss leaves in form of small (the most abundant fraction) and large aggregates. Particle count analysis highlighted that the number of particles increased while increasing the exposure time. Moreover, moss devitalization favored NP accumulation, likely because of cell membrane damages occurred in dead moss material. Post-exposure washing induced a loss of larger aggregates, suggesting that exposure time is a key point to be carefully evaluated in field conditions. These results encourage the use of S. palustre transplants for monitoring microplastics contamination of fresh water environments.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Agua Dulce/análisis , Plásticos/análisis , Sphagnopsida/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Nanopartículas/química , Plásticos/toxicidad , Poliestirenos/química
5.
J Hazard Mater ; 351: 131-137, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29529561

RESUMEN

In the present work the cytomorphological and physiological effects on three cardoon cultivars - Sardo, Siciliano, Spagnolo - grown in a metal-polluted soil, were investigated, to assess the traits concurring to the high tolerance to metal stress observed in cv. Spagnolo compared to the other two cultivars. The plants were grown for one month on a real polluted soil collected at a dismantling battery plant, highly enriched by heavy metals, especially Cd and Pb, and their leaves were analyzed by a multidisciplinary approach. TEM observations highlighted severe ultrastructural damage in Sardo and Siciliano, and preserved cytological traits in Spagnolo. Both pigment content and photochemistry indicated a decline in photosynthesis in Sardo and Sicilano and a substantial stability of the same parameters in Spagnolo. Protein analysis indicated a decrease in D1 level in all cultivars; in Spagnolo the D1 decrease was more pronounced and associated to a significant increase in Rubisco, a pattern likely preserving photosynthetic efficiency and high biomass production. In conclusion, Spagnolo cardoon was able to face metal stress through a prompt, multiple response balancing structural and functional traits.


Asunto(s)
Cynara/efectos de los fármacos , Metales Pesados/toxicidad , Contaminantes del Suelo/toxicidad , Carotenoides/metabolismo , Clorofila/metabolismo , Cynara/anatomía & histología , Cynara/citología , Cynara/metabolismo , Fotosíntesis/efectos de los fármacos , Ribulosa-Bifosfato Carboxilasa/metabolismo , Estrés Fisiológico
6.
Environ Pollut ; 239: 590-598, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29702326

RESUMEN

Investigating the nature of PM10 is crucial to differentiate sources and their relative contributions. In this study we compared the levels, and the chemical and mineralogical properties of PM10 particles sampled in different seasons at monitoring stations representative of urban background, urban traffic and suburban traffic areas of Naples city. The aims were to relate the PM10 load and characteristics to the location of the monitoring stations, to investigate the different sources contributing to PM10 and to highlight PM10 seasonal variability. Bulk analyses of chemical species in the PM10 fraction included total carbon and nitrogen, δ13C and other 20 elements. Both natural and anthropogenic sources were found to contribute to the exceedances of the EU PM10 limit values. The natural contribution was mainly related to marine aerosols and soil dust, as highlighted by X-ray diffractometry and SEM-EDS microscopy. The percentage of total carbon suggested a higher contribution of biogenic components to PM10 in spring. However, this result was not supported by the δ13C values which were seasonally homogeneous and not sufficient to extract single emission sources. No significant differences, in terms of PM10 load and chemistry, were observed between monitoring stations with different locations, suggesting a homogeneous distribution of PM10 on the studied area in all seasons. The anthropogenic contribution to PM10 seemed to dominate in all sites and seasons with vehicular traffic acting as a main source mostly by generation of non-exhaust emissions Our findings reinforce the need to focus more on the analysis of PM10 in terms of quality than of load, to reconsider the criteria for the classification and the spatial distribution of the monitoring stations within urban and suburban areas, with a special attention to the background location, and to emphasize all the policies promoting sustainable mobility and reduction of both exhaust and not-exhaust traffic-related emissions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Aerosoles/análisis , Contaminación del Aire/análisis , Carbono/análisis , Isótopos de Carbono/análisis , Ciudades , Polvo/análisis , Estaciones del Año , Emisiones de Vehículos/análisis
7.
Food Chem ; 240: 338-345, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28946281

RESUMEN

In vitro alternatives to clinical trials are used for studying human food digestion. For simulating infant digestion, only a few models, lacking physiological relevance, are available. Thanks to an extensive literature review of the in vivo infant digestive conditions, a gastrointestinal static in vitro model was developed for infants born at term and aged 28days. The model was applied to the digestion of a commercial infant formula. Kinetics of digestion, as well as the structural evolution, were compared with those obtained while submitting the same formula to the adult international consensus protocol of in vitro static digestion. The kinetics of proteolysis and lipolysis differed according to the physiological stage resulting mainly from the reduced level of enzymes and bile salts, as well as the higher gastric pH in the infant model. This in vitro static model of infant digestion is of interest for scientists, food or pharmaceutical manufacturers.


Asunto(s)
Digestión , Consenso , Humanos , Lactante , Fórmulas Infantiles , Cinética , Lipólisis
8.
Sci Total Environ ; 575: 1066-1073, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27693154

RESUMEN

In recent decades, mosses have been used as native species or as transplants in monitoring a wide range of pollutants from inorganic (i.e. metals and metalloids) to organic contaminants (mainly polycyclic aromatic hydrocarbons-PAHs). To implement the use of mosses as biomonitors of PAHs, one important issue is the study of the interactions between these compounds and moss tissues. In this study we investigated the mode of phenanthrene uptake in four moss species (Amblystegium humile, Plagiomnium affine, Hypnum cupressiforme and a clone of Sphagnum palustre) and its movements from air to plant surface and within the biomonitors, using fluorescent and confocal microscopy. The target compound, partitioned between gas and particulate phase depending on air conditions, was selected since it is one of the most abundant PAHs released into the atmosphere. Our findings support the hypothesis that phenanthrene aggregates in particles and in this form it is chiefly intercepted and uptaken onto moss surfaces, albeit with different frequency in the four species, with S. palustre>H. cupressiforme>P. affine=A. humile. Phenanthrene enters the dead, empty hyalocysts of S. palustre. Specific surface area and composition, frequency and distribution of binding groups may also explain the different ability of phenanthrene uptake by the four moss species.


Asunto(s)
Contaminantes Atmosféricos/metabolismo , Briófitas/metabolismo , Monitoreo del Ambiente , Fenantrenos/metabolismo
9.
Environ Pollut ; 225: 323-328, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28262376

RESUMEN

Although a large body of literature exists on the use of transplanted mosses for biomonitoring of air pollution, no article has addressed so far the use and the accumulation performance of a cloned moss for this purpose. In this work, a direct comparison of metal accumulation between bags filled with a Sphagnum palustre L. clone or with native Pseudoscleropodium purum Hedw., one of the most used moss species in biomonitoring surveys, was investigated. The test was performed in sites with different atmospheric contamination levels selected in urban, industrial, agricultural and background areas of Italy and Spain. Among the eighteen elements investigated, S. palustre was significantly enriched in 10 elements (Al, Ba, Cr, Cu, Fe, Hg, Pb, Sr, V and Zn), while P. purum was enriched only in 6 elements (Al, Ba, Cu, Hg, Pb and Sr), and had a consistently lower uptake capacity than S. palustre. The clone proved to be more sensitive in terms of metal uptake and showed a better performance as a bioaccumulator, providing a higher accumulation signal and allowing a finer distinction among the different land uses and levels of pollution. The excellent uptake performance of the S. palustre clone compared to the native P. purum and its low and stable baseline elemental content, evidenced in this work, are key features for the improvement of the moss bag approach and its large scale application.


Asunto(s)
Contaminantes Atmosféricos/análisis , Bryopsida/fisiología , Monitoreo del Ambiente/métodos , Sphagnopsida/fisiología , Contaminación del Aire/estadística & datos numéricos , Briófitas , Bryopsida/química , Italia , Mercurio , Metales/análisis , España , Sphagnopsida/química
10.
Sci Total Environ ; 541: 1410-1419, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26479914

RESUMEN

Inventory of emission sources and biomonitoring with moss transplants are two different methods to evaluate air pollution. In this study, for the first time, both these approaches were simultaneously applied in five municipalities in Campania (southern Italy), deserving attention for health-oriented interventions as part of a National Interest Priority Site. The pollutants covered by the inventory were CO, NOx, particulate matter (PM10), volatile organic compounds (VOCs), and some heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). The biomonitoring survey was based on the use of the devitalized moss Hypnum cupressiforme transplanted into bags, following a harmonized protocol. The exposure covered 40 agricultural and urban/residential sites, with half of them located in proximity to roads. The pollutants monitored were Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, and Zn, as well as total polycyclic aromatic hydrocarbons (PAHs) only in five sites. Using the emission inventory approach, high emission loads were detected for all the major air pollutants and the following heavy metals: Cr, Cu, Ni, Pb and Zn, over the entire study area. Arsenic, Pb, and Zn were the elements most accumulated by moss. Total PAH postexposure contents were higher than the preexposure values (~20-50% of initial value). Moss uptakes did not differ substantially among municipalities or within exposure sites. In the five municipalities, a similar spatial pattern was evidenced for Pb by emission inventory and moss accumulation. Both approaches indicated the same most polluted municipality, suggesting their combined use as a valuable resource to reveal contaminants that are not routinely monitored.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Contaminación del Aire/estadística & datos numéricos , Briófitas/química , Bryopsida/química , Ciudades , Sustancias Peligrosas , Italia , Metales Pesados/análisis , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
11.
Chemosphere ; 149: 211-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26855226

RESUMEN

In this paper we investigated the possibility to use moss bags to detect pollution inputs - metals, metalloids and polycyclic aromatic hydrocarbons (PAHs) - in sites chosen for their different land use (agricultural, urban/residential scenarios) and proximity to roads (sub-scenarios), in a fragmented conurbation of Campania (southern Italy). We focused on thirty-nine elements including rare earths. For most of them, moss uptake was higher in agricultural than in urban scenarios and in front road sites. Twenty PAHs were analyzed in a subset of agricultural sites; 4- and 5-ringed PAHs were the most abundant, particularly chrysene, fluoranthene and pyrene. Overall results indicated that investigated pollutants have a similar spatial distribution pattern over the entire study area, with road traffic and agricultural practices as the major diffuse pollution sources. Moss bags proved a very sensitive tool, able to discriminate between different land use scenarios and proximity to roads in a mixed rural-urban landscape.


Asunto(s)
Contaminantes Atmosféricos/análisis , Briófitas/química , Monitoreo del Ambiente/métodos , Atmósfera/química , Humanos , Italia , Metales/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
12.
Environ Pollut ; 214: 362-373, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27108040

RESUMEN

To develop an internationally standardized protocol for the moss bag technique application, the research team participating in the FP7 European project "MOSSclone" focused on the optimization of the moss bags exposure in terms of bag characteristics (shape of the bags, mesh size, weight/surface ratio), duration and height of exposure by comparing traditional moss bags to a new concept bag, "Mossphere". In particular, the effects of each variable on the metal uptake from the air were evaluated by a systematic experimental design carried out in urban, industrial, agricultural and background areas of three European countries with oceanic, Mediterranean and continental climate. The results evidenced that the shape, the mesh size of the bags and the exposure height (in the tested ranges), did not significantly influence the uptake capacity of the transplanted moss. The aspects more affecting the element uptake were represented by the density of the moss inside the bags and the relative ratio between its weight and the surface area of the bag. We found that, the lower the density, the higher the uptake recorded. Moreover, three weeks of exposure were not enough to have a consistent uptake signal in all the environments tested, thus we suggest an exposure period not shorter than 6 weeks, which is appropriate in most situations. The above results were confirmed in all the countries and scenarios tested. The adoption of a shared exposure protocol by the research community is strongly recommended since it is a key aspect to make biomonitoring surveys directly comparable, also in view of its recognition as a monitoring method by the EU legislation.


Asunto(s)
Contaminantes Atmosféricos/análisis , Briófitas , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/normas , Metales/análisis , Clima , Europa (Continente) , Internacionalidad
13.
J Magn Reson ; 138(2): 277-80, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10341131

RESUMEN

An inexpensive external unit that allows the use of a commercial high-resolution NMR spectrometer as a very low frequency instrument is described. The external unit is phase coherent, the pulse timing being given by the parent spectrometer. With the exception of the probe, the external unit does not contain any tuned elements. This permits easy change of frequency in the range 100 kHz-1 MHz. The external unit may be appropriately employed in food science where, in several cases, low frequency is desirable. An application to hen shell eggs at the frequency of 700 kHz is described.


Asunto(s)
Huevos/análisis , Análisis de los Alimentos/instrumentación , Espectroscopía de Resonancia Magnética/instrumentación , Animales , Análisis Costo-Beneficio , Cáscara de Huevo , Diseño de Equipo , Análisis de los Alimentos/economía , Magnetismo , Transductores
14.
J Magn Reson ; 147(1): 89-94, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11042050

RESUMEN

In this paper chemometrics (ANOVA and PCR) is used to measure unbiased correlations between NMR spin-echo decays of pork M. Longissimus dorsi obtained through Carr-Purcell-Meiboom-Gill (CPMG) experiments at low frequency (20 MHz) and the values of 14 technological parameters commonly used to assess pork meat quality. On the basis of the ANOVA results, it is also found that the CPMG decays of meat cannot be best interpreted with a "discrete" model (i.e., by expanding the decays in a series of a discrete number of exponential components, each with a different transverse relaxation time), but rather with a "continuous" model, by which a continuous distribution of T(2)'s is allowed. The latter model also agrees with literature histological results.


Asunto(s)
Carne/análisis , Algoritmos , Análisis de Varianza , Animales , Femenino , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética/métodos , Masculino , Análisis de Regresión , Porcinos , Temperatura
15.
J Agric Food Chem ; 48(5): 1623-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10820069

RESUMEN

Technomimetic NMR experiments were performed in accordance with the lye treatment adopted during table olive industrial procedures for the debittering process causing oleuropein degradation. The site selective hydrolysis of the two ester groups, characterizing the biophenolic secoiridoid molecule, was shown to be dependent on the different reactivities of these functionalities. The process is controlled by the experimental conditions exerted on the olive pulp and determined by the buffering capacity of the olive mesocarp and by the epicarp molecular components influencing the reactant penetration into the fruit pulp. The overall hydrolytic process of oleuropein, the bitter principle of olives, using the technomimetic experimental mode, gave rise to its catabolic derivatives, hydroxytyrosol, 11-methyloleoside, and the monoterpene glucoside, technomimetically produced, isolated, and structurally characterized by (1)H, (13)C, and COSY spectroscopy as the oleoside.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Piranos/química , Hidrólisis , Glucósidos Iridoides , Iridoides
16.
Percept Mot Skills ; 54(3 Pt 2): 1119-22, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7110852

RESUMEN

2 groups of language-disordered children were studied regarding the reading levels reached at the end of the first year of school. The first group was composed by children with language retardation mainly on phonological level, the second group was composed by children with retardation also on semantic-syntactic level. The results confirmed the strong association between reading disability and language disorders and yielded significant differences between the two groups: the reading achievement seemed to be associated mainly to semantic and syntactic competences.


Asunto(s)
Desarrollo Infantil , Dislexia/psicología , Trastornos del Desarrollo del Lenguaje/psicología , Trastornos del Lenguaje/psicología , Logro , Niño , Preescolar , Femenino , Humanos , Masculino , Fonética , Pronóstico , Semántica , Escritura
17.
Pediatr Med Chir ; 15 Suppl 1: 29-33, 1993.
Artículo en Italiano | MEDLINE | ID: mdl-8415192

RESUMEN

The present work compares the neuropsychological and cognitive profiles of 4 children with the Williams and Down syndrome. The Authors stress the importance of an accurate analysis of each child's developmental story. They monitor children with physical malformations associated to Mental Retardation or other psychopathological problems in order to have a better understanding of their cognitive strategies and true potential and of their social and emotional implications. This procedure allows immediate action to be taken as soon as physical, emotional or cognitive problems arise. It also enables parents to be fully aware of their children's problems and to be able to meet their different developmental needs.


Asunto(s)
Anomalías Múltiples/psicología , Estenosis de la Válvula Aórtica/psicología , Cognición , Síndrome de Down/psicología , Expresión Facial , Hipercalcemia/psicología , Discapacidad Intelectual/psicología , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/epidemiología , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/epidemiología , Niño , Síndrome de Down/diagnóstico , Síndrome de Down/epidemiología , Estudios de Seguimiento , Humanos , Hipercalcemia/diagnóstico , Hipercalcemia/epidemiología , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/epidemiología , Italia/epidemiología , Pruebas Neuropsicológicas , Neuropsicología , Síndrome
18.
Phys Rev Lett ; 96(4): 042503, 2006 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-16486813

RESUMEN

The mixed occurrence of s-wave and p-wave contributions in a first forbidden unique Gamow-Teller beta decay has been investigated for the first time by measuring the beta environmental fine structure (BEFS) in a 187Re crystalline compound. The experiment has been carried out with an array of eight AgReO4 thermal detectors operating at a temperature of approximately 100 mK. A fit of the observed BEFS spectrum indicates the p-wave electron emission as the dominant channel. The complete understanding of the BEFS distortion of the 187Re beta decay spectrum is crucial for future experiments aiming at the precise calorimetric measurement of the antineutrino mass.

19.
Eur J Biochem ; 212(1): 69-78, 1993 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-8444166

RESUMEN

1H one-dimensional and two-dimensional NMR spectra have been recorded for the oxidized and reduced forms of the high-potential iron-sulfur protein (HiPIP) from Rhodopseudomonas globiformis which has the highest known reduction potential. The spectrum of the oxidized protein is similar to that of Chromatium vinosum and Rhodocyclus gelatinosus HiPIP but different from that of the HiPIP II from Ectothiorhodospira halophila. Surprisingly, site-specific assignment has shown that in the oxidized protein the distribution of oxidation numbers within the cluster is very similar to that found for E. halophila HiPIP II and different from that of the other two proteins. The spectrum of the reduced species is very similar to that of all other HiPIPs known to date, indicating very similar electronic and geometric structures for the reduced forms. These findings are discussed in terms of cluster structure in HiPIPs and of redox potentials.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Hierro-Azufre/química , Proteínas del Complejo del Centro de Reacción Fotosintética , Rhodopseudomonas/química , Secuencia de Aminoácidos , Espectroscopía de Resonancia Magnética , Oxidación-Reducción
20.
Ultrastruct Pathol ; 4(1): 51-9, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6857764

RESUMEN

Two cases of primary renal carcinoidal tumor are reported. One was discovered in a 32-year-old pregnant woman. The other tumor was retrospectively diagnosed 3 years after nephrectomy in a 65-year-old woman who was hospitalized with a metastatic lesion in her lumbar spine. Both tumors are compared with 5 other cases previously reported in the literature, and hypotheses about the cause of renal localization of this tumor are reviewed.


Asunto(s)
Tumor Carcinoide/patología , Neoplasias Renales/patología , Complicaciones Neoplásicas del Embarazo/patología , Adulto , Tumor Carcinoide/etiología , Tumor Carcinoide/ultraestructura , Femenino , Humanos , Neoplasias Renales/etiología , Neoplasias Renales/ultraestructura , Microscopía Electrónica , Embarazo
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