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1.
Sci Total Environ ; 879: 163095, 2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37001666

RESUMEN

Coastal lagoons are ecosystems that are considered providers of a variety species of commercial value to the humans. However, they are currently threatened by a variety of anthropogenic-derived impacts, including environmental pollution by microplastics (MPs). For these reasons, it is necessary to identify suitable biomonitors for monitoring MP activities in aquatic environments and for estimating human ingestion of MPs from the consumption of commercial shellfish species. Therefore, our aims were to identify the anthropogenic activities that supply MPs into a coastal lagoon in the southern Gulf of Mexico and their variety; to determine whether oysters (Crassostrea virginica) are suitable biomonitors to perform MPs monitoring activities and to conduct an estimation of how many MPs could a human consume by the ingestion of a commercial portion of oysters harvested in this coastal lagoon. Our results noted that MP concentrations from water and sediment collected in Laguna de Terminos were 210,000 and 11.3 times higher than values reported in other protected areas worldwide. MPs chemical composition revealed that fishing and urban activities supply mainly polyethylene (21.1 %), poly (butadiene) diol (12.6 %) and polyethylene terephthalate (9.5 %). It was also determined that oysters did not reflect the spatial distribution of MPs within the study area and that a human could consume up to 806.1 MPs per 237.1 g serving of an oyster cocktail. Finally, a coastal lagoon polluted with MPs increases the risk of affecting species used for human consumption.


Asunto(s)
Crassostrea , Contaminantes Químicos del Agua , Animales , Humanos , Microplásticos , Ecosistema , Plásticos , Mariscos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos
2.
Sports Biomech ; : 1-15, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34845976

RESUMEN

Competitive progressions are necessary to ensure that peak performance occurs when medals are decided. This study aimed to: i) study the coefficient of variation (CV) and performance changes (%Δ) among swimmers who participated in different rounds (i.e., heats, semi-finals and finals); ii) study the CV changes as a function of FINA-points. A total of 1447 performances were analysed in the 100 and 200 m-races during the Budapest 2021 European-Championships. Linear mixed-effects models were applied for total and split-times to obtain intra-athlete CV and %Δ. The FINA-points were studied with two-way ANOVA and Pearson's correlation assessed the relations with CV. The CV in 100 m-races was: 0.48 ± 0.21% for males and 0.50 ± 0.20% for females (Δ = -0.66%); in 200 m-races: 0.63 ± 0.36% and 0.60 ± 0.34% (Δ = -0.82%). There were differences in FINA-points between strokes and distances (p < 0.02) associated with higher CV for the 200 m-races (r = 0.37; p = 0.003), indicating changes in performance over the rounds. Swimmers' finalists performed easier during the heats by going slower in the first 50 m-lap; however, some of them would have little chance of qualifying during major championships because some events were below FINA-points world-standards.

3.
Ther Innov Regul Sci ; 55(6): 1165-1179, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34181236

RESUMEN

BACKGROUND: The PARADIGM consortium aimed to make patient engagement in the development and lifecycle management of medicines easier and more effective for all, with the development of new tools that fulfil robustly defined gaps where engagement is suboptimal. AIMS: To generate an inventory of gaps in patient engagement practices and process from existing global examples. METHODS: A large set of criteria for effective patient engagement previously defined via a multi-stakeholder Delphi method, were mapped under fourteen overarching themes. A gap analysis was then performed by twenty-seven reviewers against the resulting forty-six mapped criteria, on a sample of seventy initiatives from global databases. RESULTS: An inventory of gaps was identified including contextual information as to why the gaps exist. Our work identified general patterns where patient engagement was suboptimal-defined as; fragmented reporting and dissemination of patient engagement activities, and the fundamental principles defined in frameworks or guidance being poorly adhered to in actual practice. Specific gaps were identified for sixteen criteria. Additionally, it was also common to observe primary aspects of a process were addressed for a given criteria (i.e. training for roles and responsibilities) but a secondary context element was lacking (i.e. making training material accessible/understandable/meaningful to all participants). CONCLUSION: The results show that the evolution towards meaningful and systematic patient engagement is occurring, yet more importantly they provide clear directional insights to help enhance collaborative practices and co-design solutions. This targeted impact to catalyse a needs-oriented health system that integrates patient engagement at its core is essential.


Asunto(s)
Participación del Paciente , Humanos
4.
Eur Rev Med Pharmacol Sci ; 24(20): 10601-10604, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33155217

RESUMEN

OBJECTIVE: CD147 is the main inducer of extracellular matrix metalloproteinases, which are critically involved in different inflammatory diseases. Our objective was to assess whether in vitro stimulation with Th1 and Th17 cytokines modulate CD147 production in monocytes from psoriasis patients. PATIENTS AND METHODS: Serum CD147 levels were measured in 60 psoriasis patients and 60 healthy controls. Furthermore, CD14+ monocytes were cultured and stimulated with TNF, IFN-g or IL-17A, and CD147 production was measured. RESULTS: Serum CD147 levels were higher in psoriasis patients (median 1866, IQR 1517-2355 pg/mL vs. 1686, 1382-1947 pg/mL; p=0.023), allowing to distinguish between patients and controls (AUC-ROC 0.632 ± 0.0509). Baseline CD147 production was similar in monocytes from patients and controls (1298, 769-1645 pg/mL vs. 1290, 1048-1976 pg/ml, respectively). Stimulation with IL-17A (1638, 1426-2027 pg/mL; p<0.001), but no other cytokine, was associated with increased production of CD147 in monocytes from psoriatic patients. In contrast, none of the cytokines increased CD147 production in monocytes from healthy controls. CONCLUSIONS: CD147 production by activated monocytes is a cytokine-dependent process, specifically by cytokines of the Th17 phenotype instead of those belonging to the Th1 phenotype. CD147 is a novel inflammatory mediator that could be a therapeutic target in psoriasis.


Asunto(s)
Basigina/biosíntesis , Interleucina-17/metabolismo , Monocitos/metabolismo , Psoriasis/metabolismo , Adulto , Basigina/sangre , Células Cultivadas , Femenino , Humanos , Interleucina-17/genética , Masculino , Persona de Mediana Edad , Psoriasis/sangre , Psoriasis/diagnóstico
5.
J Phys Chem A ; 121(32): 6079-6089, 2017 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-28678482

RESUMEN

To dispose of atomic oxygen, it is necessary the O2 activation; however, an energy barrier must be overcome to break the O-O bond. This work presents theoretical calculations of the O2 adsorption and dissociation on small pure Aun and Agm and bimetallic AunAgm (n + m ≤ 6) clusters using the density functional theory (DFT) and the zeroth-order regular approximation (ZORA) to explicitly include scalar relativistic effects. The most stable AunAgm clusters contain a higher concentration of Au with Ag atoms located in the center of the cluster. The O2 adsorption energy on pure and bimetallic clusters and the ensuing geometries depend on the spin multiplicity of the system. For a doublet multiplicity, O2 is adsorbed in a bridge configuration, whereas for a triplet only one O-metal bond is formed. The charge transfer from metal toward O2 occupies the σ*O-O antibonding natural bond orbital, which weakens the oxygen bond. The Au3 (2A) cluster presents the lowest activation energy to dissociate O2, whereas the opposite applies to the AuAg (3A) system. In the O2 activation, bimetallic clusters are not as active as pure Aun clusters due to the charge donated by Ag atoms being shared between O2 and Au atoms.

6.
Mucosal Immunol ; 10(5): 1237-1247, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28120846

RESUMEN

The intestinal epithelium constitutes a first line of defense of the innate immune system. Epithelial dysfunction is a hallmark of intestinal disorders such as inflammatory bowel diseases (IBDs). The actin cytoskeleton controls epithelial barrier integrity but the function of actin regulators such as cortactin is poorly understood. Given that cortactin controls endothelial permeability, we hypothesized that cortactin is also important for epithelial barrier regulation. We found increased permeability in the colon of cortactin-KO mice that was accompanied by reduced levels of ZO-1, claudin-1, and E-cadherin. By contrast, claudin-2 was upregulated. Cortactin deficiency increased RhoA/ROCK1-dependent actomyosin contractility, and inhibition of ROCK1 rescued the barrier defect. Interestingly, cortactin deficiency caused increased epithelial proliferation without affecting apoptosis. KO mice did not develop spontaneous colitis, but were more susceptible to dextran sulfate sodium colitis and showed severe colon tissue damage and edema formation. KO mice with colitis displayed strong mucus deposition and goblet cell depletion. In healthy human colon tissues, cortactin co-localized with ZO-1 at epithelial cell contacts. In IBDs patients, we observed decreased cortactin levels and loss of co-localization with ZO-1. Thus, cortactin is a master regulator of intestinal epithelial barrier integrity in vivo and could serve as a suitable target for pharmacological intervention in IBDs.


Asunto(s)
Actomiosina/metabolismo , Colitis/inmunología , Cortactina/metabolismo , Enfermedades Inflamatorias del Intestino/inmunología , Mucosa Intestinal/patología , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Apoptosis , Proliferación Celular , Colitis/inducido químicamente , Cortactina/genética , Citoesqueleto/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Humanos , Inmunidad Innata , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína de la Zonula Occludens-1/metabolismo , Proteína de Unión al GTP rhoA/genética
7.
J Food Sci Technol ; 53(1): 281-92, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26787948

RESUMEN

Pomegranate extract, vanillin and geraniol were studied as natural antimicrobials on strawberry juice. Strawberry juice was treated with each agent at two concentrations: pomegranate extract at 180 and 360 µg/mL; vanillin at 2.5 and 5 mg/mL; and geraniol at 0.6 and 1.2 µL/mL. After being treated, juices were stored at 5 °C and microbiological, physicochemical and sensory studies were carried out. Also, a second batch of juice was inoculated with Escherichia coli O157:H7 (10(5) CFU/mL) before being treated, to safety study. Geraniol and vanillin, at both concentrations tested, were highly effective in reducing the native microflora on strawberry juice (more than 3 log cycles), extending the microbiological shelf-life of the product. Moreover, both antimicrobials improved the product safety by reducing inoculated E. coli O157:H7. Furthermore, vanillin showed a significant increase in polyphenol content compared to untreated juice. On the other hand, pomegranate extract applied at the highest concentration showed important reductions on mesophilic and psychrophilic bacteria, but no effect on yeast and molds and inoculated E. coli. Even though vanillin and geraniol incorporation on strawberry juice had a negative effect on its sensory quality, pomegranate extract had no impact on the sensory attributes evaluated. Combinations of the biopreservatives could be studied in order to decrease the concentration of the antimicrobials, reducing the effects on strawberry juice sensory characteristics.

9.
J Appl Phys ; 117(3): 034306, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25641981

RESUMEN

In this work, we report the fabrication of self-assembled zinc oxide nanorods grown on pentagonal faces of silver nanowires by using microwaves irradiation. The nanostructures resemble a hierarchal nanoantenna and were used to study the far and near field electrical metal-semiconductor behavior from the electrical radiation pattern resulting from the phase map reconstruction obtained using off-axis electron holography. As a comparison, we use electric numerical approximations methods for a finite number of ZnO nanorods on the Ag nanowires and show that the electric radiation intensities maps match closely the experimental results obtained with electron holography. The time evolution of the radiation pattern as generated from the nanostructure was recorded under in-situ radio frequency signal stimulation, in which the generated electrical source amplitude and frequency were varied from 0 to 5 V and from 1 to 10 MHz, respectively. The phase maps obtained from electron holography show the change in the distribution of the electric radiation pattern for individual nanoantennas. The mapping of this electrical behavior is of the utmost importance to gain a complete understanding for the metal-semiconductor (Ag/ZnO) heterojunction that will help to show the mechanism through which these receiving/transmitting structures behave at nanoscale level.

11.
Semin Cell Dev Biol ; 36: 149-56, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25242280

RESUMEN

The exchange of substances between metazoan and the environment takes place across transporting epithelia that have two fundamental differentiated features: tight junctions (TJ) and apical/basolateral polarity. Usually, reviews of the structure and function of transporting epithelia follow a historical description of major biological findings, but seldom refer to the fact that it also required fundamental theoretical changes in the physics and chemistry involved. We make a brief description of the concatenation of both types of achievements, in which it becomes clear that the major source of conflicts was the enzyme Na(+),K(+)-ATPase (also referred to as "the pump"), because of its intrinsic mechanisms and its asymmetric expression on one side of epithelial cells only (polarity). This enzyme is also the receptor of the newly recognized hormone ouabain, whose chief function is to modulate cell contacts, such as TJs, several types of cell-cell contacts participating in polarization (as gauged through ciliogenesis).


Asunto(s)
Células Epiteliales/fisiología , Epitelio/fisiología , Ouabaína/metabolismo , Uniones Estrechas/fisiología , Transporte Biológico , Cilios/metabolismo , Claudina-2 , Humanos , Permeabilidad , ATPasa Intercambiadora de Sodio-Potasio
12.
Lett Appl Microbiol ; 59(4): 449-56, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24979232

RESUMEN

Functional foods targeting the improvement of gastrointestinal health are widely recognized; of these, dairy-based probiotics are the most popular. Thus, the design of nondairy probiotics applying fruits, vegetables and cereals has raised great interest in the healthy food sector. The objective of this work was to assess the potential of germinated and malted oat substrates to support the growth of the probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus rhamnosus. Fermentations were carried out with distinctive oat substrates at inoculum levels of 3, 5 and 7% v/v, substrate concentrations of 3, 5 and 7% w/v and with sucrose addition 1·5% w/v. Lag phase profiles, maximum growth rates and maximal growths were evaluated; protein and sugar contents were also quantified. There was no significant effect (P > 0·05) of the inoculum size on the fermentation kinetics; however, oat media significantly affected the growth kinetics. In simple oat media, Lact. acidophilus exhibited biphasic growth patterns. Lactobacillus growth patterns were significantly affected (P < 0·05) by the supplementation with protein sources. The germination and malting processes significantly improved oats nutrient characteristics demonstrating to be adequate substrates for the fermentation with probiotic lactobacilli. Significance and impact of the study: In this work, the effect of oat media composition and fermentation conditions on the growth kinetics of three probiotic lactobacilli was determined. The variation in the inoculum levels did not have a significant effect on the probiotic cultures growth. Results revealed that protein supplemented simple, germinated and malted oat enhanced the cell viability of the probiotic lactobacilli; Lactobacillus casei exhibited better growth adaptability. The results also highlight that different weight in volume oat substrate concentrations has particular effects on Lact. casei growth kinetics. Our results contribute to a better understanding of oat-based media formulations as substrates for probiotic cultures.


Asunto(s)
Avena/metabolismo , Lacticaseibacillus casei/fisiología , Lacticaseibacillus rhamnosus/fisiología , Lactobacillus acidophilus/fisiología , Probióticos , Avena/fisiología , Fermentación , Germinación
13.
Gen Comp Endocrinol ; 203: 186-92, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24698785

RESUMEN

The 17ß-hydroxysteroid dehydrogenases (17ß-HSD) are key enzymes involved in the formation (reduction) and inactivation (oxidation) of sex steroids. Several types have been found in vertebrates including fish, as well as in invertebrates like Caenorhabditis elegans, Ciona intestinalis and Haliotis diversicolor supertexta. To date limited information is available about this enzyme in parasites. We showed previously that Taenia solium cysticerci are able to synthesize sex steroid hormones in vitro when precursors are provided in the culture medium. Here, we identified a T. solium 17ß-HSD through in silico blast searches in the T. solium genome database. This coding sequence was amplified by RT-PCR and cloned into the pcDNA 3.1(+) expression vector. The full length cDNA contains 957bp, corresponding to an open reading frame coding for 319 aa. The highest identity (84%) at the protein level was found with the Echinococcus multilocularis 17ß-HSD although significant similarities were also found with other invertebrate and vertebrate 17ß-HSD sequences. The T. solium Tsol-17ßHSD belongs to the short-chain dehydrogenase/reductase (SDR) protein superfamily. HEK293T cells transiently transfected with Tsol17ß-HSD induced expression of Tsol17ß-HSD that transformed 3H-androstenedione into testosterone. In contrast, 3H-estrone was not significantly transformed into estradiol. In conclusion, T. solium cysticerci express a 17ß-HSD that catalyzes the androgen reduction. The enzyme belongs to the short chain dehydrogenases/reductase family and shares motifs and activity with the type 3 enzyme of some other species.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/genética , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Hormonas Esteroides Gonadales/biosíntesis , Taenia solium/enzimología , Taenia solium/genética , Secuencia de Aminoácidos , Androstenodiona/biosíntesis , Animales , Secuencia de Bases , Clonación Molecular , Regulación de la Expresión Génica , Células HEK293 , Humanos , Datos de Secuencia Molecular , Filogenia , Testosterona/biosíntesis
14.
J Appl Phys ; 115(2): 24301, 2014 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24453381

RESUMEN

A giant magnetoresistance effect (∼46% at 20 K under 7 T) and anomalous magnetic properties were found in a highly epitaxial double perovskite LaBaCo2O5.5+δ (LBCO) thin film on (001) MgO. Aberration-corrected Electron Microscopy and related analytical techniques were employed to understand the nature of these unusual physical properties. The as-grown film is epitaxial with the c-axis of the LBCO structure lying in the film plane and with an interface relationship given by (100)LBCO || (001)MgO and [001]LBCO || [100]MgO or [010]MgO. Orderly oxygen vacancies were observed by line profile electron energy loss spectroscopy and by atomic resolution imaging. Especially, oxygen vacancy and nanodomain structures were found to have a crucial effect on the electronic transport and magnetic properties.

15.
Rev Esp Med Nucl Imagen Mol ; 33(2): 112-4, 2014.
Artículo en Español | MEDLINE | ID: mdl-24119550

RESUMEN

Prostate tumors originate 68% in the peripheral region and 24% in the transitional region where tumors originating in the central zone are rare (8%). However, diagnosis of the tumors in the central zone is important since they exhibit greater aggressiveness conditioned by their location and different biological behavior. Magnetic resonance imaging shows problems in identifying lesions in the central prostate zone, since this region has a heterogeneous signal, mainly after the primary treatment. Ultrasound guided sextant biopsy shows a negative result in 28% of prostate tumors. Therefore, it is advisable to repeat or even to perform saturation biopsies. We present two patients, one of them with suspected biochemical prostate cancer and one with biochemical recurrence after radical treatment. In both, (11)C-Choline PET/CT allowed detection of the tumor focus in the central zone of the prostate, with negative complementary diagnostic test and biopsies.


Asunto(s)
Radioisótopos de Carbono , Colina , Imagen Multimodal , Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico , Tomografía Computarizada por Rayos X , Anciano , Humanos , Masculino
16.
Rev Esp Med Nucl Imagen Mol ; 33(1): 28-31, 2014.
Artículo en Español | MEDLINE | ID: mdl-23499124

RESUMEN

Early localization of biochemical recurrence in patients after radical treatment of prostate cancer is a widely accepted clinical indication of (11)C-choline PET/CT. Its widespread clinical use has prompted the depiction of incidentalomas, unusual sites of metastatic lesions, as well as false positive and negative cases. Over the last 6 years, a total of 454 (11)C-choline PET/CT studies have been performed in our institution to locate biochemical recurrence of patients with prostate cancer. With these studies, a second neoplasm has been found in 7 patients (1.54%): 3 lung, 2 colorectal, 1 esophagus and 1 esophageal junction, respectively. Although the clinical usefulness of this technique for detecting cancer lesions other than prostate origin is known for those patients who undergo this technique in the accepted indication, the diagnosis of a second tumor has a significant impact on their therapeutic management.


Asunto(s)
Neoplasias Primarias Múltiples/diagnóstico por imagen , Neoplasias Primarias Secundarias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Braquiterapia , Radioisótopos de Carbono , Colina , Neoplasias Colorrectales/diagnóstico por imagen , Terapia Combinada , Diagnóstico Diferencial , Neoplasias Esofágicas/diagnóstico por imagen , Humanos , Hallazgos Incidentales , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Recurrencia Local de Neoplasia/diagnóstico por imagen , Prostatectomía , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/secundario , Neoplasias de la Próstata/cirugía , Radiofármacos
18.
Rev Gastroenterol Mex ; 78(4): 203-10, 2013.
Artículo en Español | MEDLINE | ID: mdl-24290320

RESUMEN

BACKGROUND: Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by abdominal pain or discomfort that is associated with altered bowel habit. Both its prevalence and clinical characteristics vary throughout Latin America. A percentage of patients does not seek medical attention, therefore a reliable prevalence figure can only be established by interviewing non-selected populations. AIMS: To study the prevalence and clinical characteristics of IBS symptoms in non-selected subjects in Santiago, Chile. METHODS: A total of 437 shopping mall visitors above the age of 15 years (246 women) participated in the study by answering the Rome II validated questionnaire for IBS. The demographic and socioeconomic backgrounds, comorbidities, and a family history of IBS were registered. RESULTS: A total of 64.1% subjects reported having gastrointestinal symptoms and 28.6% had symptoms suggestive of IBS. When the subjects with IBS symptoms were compared with the asymptomatic individuals, a predominance of women (65.6 vs. 42.9, P<.001) and a greater cholecystectomy frequency (33.6 vs. 12.9% P<.05) were observed in the former. The age of symptom onset was 30.4 years. An equal percentage of subjects (42.4%) presented with diarrhea and constipation and 15.2% presented with alternating IBS. Participants with a higher educational level reported a lower percentage of IBS (P<.05). A family history of the disease was present in 40% of the subjects with IBS, compared with 14.9% in the asymptomatic individuals (P<.05). Only 39.2% of the subjects had seen a physician for their symptoms and the treatment and tests ordered were inappropriate. CONCLUSION: The prevalence of IBS symptoms in the population studied is one of the highest described. Therefore, health teams should have the necessary knowledge and skill required for its management.


Asunto(s)
Síndrome del Colon Irritable/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Chile/epidemiología , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Calidad de Vida , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
19.
Micron ; 54-55: 82-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24055122

RESUMEN

The purpose of this paper is to show surface irregularities in gold decahedra nanoparticles extracted by using off-axis electron holography in a JEOL ARM 200F microscope. Electron holography has been used in a dual-lens system within the objective lenses: main objective lens and objective minilens. Parameters such as biprism voltage, fringe spacing (σ), fringe width (W) and optimum fringe contrast have been calibrated. The reliability of the transmission electron microscope performance with these parameters was carried out through a plug-in in the Digital-Micrograph software, which considers the mean inner potential within the particle leading a precise determination of the morphological surface of decahedral nanoparticles obtained from the reconstructed unwrapped phase and image processing. We have also shown that electron holography has the capability to extract information from nanoparticle shape that is currently impossible to obtain with any other electron microscopy technique.

20.
Science ; 332(6034): 1149; author reply 1149, 2011 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-21622707

RESUMEN

Wolfe-Simon et al. (Research Articles, 3 June 2011, p. 1163; published online 2 December 2010) argued that the bacterial strain GFAJ-1 can vary the elemental composition of its biomolecules by substituting arsenic for phosphorus. Although their data show that GFAJ-1 is an extraordinary extremophile, consideration of arsenate redox chemistry undermines the suggestion that arsenate can replace the physiologic functions of phosphate.


Asunto(s)
Arsénico/metabolismo , Halomonadaceae/metabolismo , Fósforo/metabolismo , Adaptación Fisiológica , Arseniatos/química , Arsénico/análisis , Arsénico/química , Arsenitos/química , Halomonadaceae/crecimiento & desarrollo , Estructura Molecular , Oxidación-Reducción , Fosfatos/química
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