Novel reinforced cross‐linked lysozyme crystals containing homogeneous dispersions of single‐walled carbon nanotubes bundles (SWCNTs) are produced and characterized. The incorporation of SWCNTs ...inside lysozyme crystals gives rise to reinforced composite materials with tunable mechanical strength and electronic conductivity, while preserving the crystal quality and morphology. These reinforced crystals show increased catalytic activity at higher temperatures, being active even above the denaturation temperature. The electron transport through the crystals is linked to the content and distribution of SWCNT bundles inside the crystals. The electron conduction through the crystals is isotropic and very efficient, presenting high conductivity values up to 600 nS at very low (0.05 wt%) SWCNT concentration. To obtain these crystals, a new protocol based on the in situ crystallization of lysozyme in composite SWCNT–peptide hydrogels is developed. These peptide hydrogels are able to homogeneously disperse bundles of hydrophobic SWCNTs allowing first, the crystallization of the enzyme lysozyme and second, transferring the new properties of the inorganic component to the crystals. Taken together, these composite crystals represent an example of the versatility of proteins as biological substrates in the generation of novel functional materials, opening the door to use them in catalysis and bioelectronics at macroscale.
Novel composite materials based on the incorporation of single‐walled carbon nanotubes inside lysozyme crystals are produced. The inclusion of carbon nanotubes gives rise to crystals with tunable mechanical strength and electronic conductivity. The catalytic activity of these reinforced crystals improves at higher temperature. These crystals are obtained by an in situ lysozyme crystallization in composite peptide–carbon nanotube hydrogels.
The fetus can deploy a local or systemic inflammatory response when exposed to microorganisms or, alternatively, to non-infection-related stimuli (e.g., danger signals or alarmins). The term “Fetal ...Inflammatory Response Syndrome” (FIRS) was coined to describe a condition characterized by evidence of a systemic inflammatory response, frequently a result of the activation of the innate limb of the immune response. FIRS can be diagnosed by an increased concentration of umbilical cord plasma or serum acute phase reactants such as C-reactive protein or cytokines (e.g., interleukin-6). Pathologic evidence of a systemic fetal inflammatory response indicates the presence of funisitis or chorionic vasculitis. FIRS was first described in patients at risk for intraamniotic infection who presented preterm labor with intact membranes or preterm prelabor rupture of the membranes. However, FIRS can also be observed in patients with sterile intra-amniotic inflammation, alloimmunization (e.g., Rh disease), and active autoimmune disorders. Neonates born with FIRS have a higher rate of complications, such as early-onset neonatal sepsis, intraventricular hemorrhage, periventricular leukomalacia, and death, than those born without FIRS. Survivors are at risk for long-term sequelae that may include bronchopulmonary dysplasia, neurodevelopmental disorders, such as cerebral palsy, retinopathy of prematurity, and sensorineuronal hearing loss. Experimental FIRS can be induced by intra-amniotic administration of bacteria, microbial products (such as endotoxin), or inflammatory cytokines (such as interleukin-1), and animal models have provided important insights about the mechanisms responsible for multiple organ involvement and dysfunction. A systemic fetal inflammatory response is thought to be adaptive, but, on occasion, may become dysregulated whereby a fetal cytokine storm ensues and can lead to multiple organ dysfunction and even fetal death if delivery does not occur (“rescued by birth”). Thus, the onset of preterm labor in this context can be considered to have survival value. The evidence so far suggests that FIRS may compound the effects of immaturity and neonatal inflammation, thus increasing the risk of neonatal complications and long-term morbidity. Modulation of a dysregulated fetal inflammatory response by the administration of antimicrobial agents, anti-inflammatory agents, or cell-based therapy holds promise to reduce infant morbidity and mortality.
The ability to accurately determine metal mercury content and identify different mercury species in solid samples is essential for developing remediation and control strategies. The aim of the ...present study is to characterize mercury compounds based on thermal desorption. For this purpose a series of samples was prepared and the operational parameters—heating velocity, carrier gas—were optimized. Fifteen commercial mercury compounds were analyzed for use as fingerprints. The results of the study show that the identification of mercury species by the method of thermal desorption is possible. The temperature of desorption increased according to the following order HgI2<HgBr2<Hg2Cl2åHgCl2<Hg(CN)2<HgCl2O8·H2O<Hg(SCN)2<HgS (red)<HgF2<Hg2(NO3)2·2H2O<Hg(NO3)2·H2O<HgO (yellow, red)<Hg2SO4<HgSO4. A comparison of the estimated total mercury content with the mercury content calculated by integrating the area of the desorption curve shows that recoveries of 79–104% for HgS can be estimated. The proposed method represents a significant step forward in direct mercury analysis in solid samples.
•Application of thermal-desorption procedure for mercury speciation in solid samples.•Thermal desorption profiles for fifteen mercury compounds have been obtained.•Mercury compounds have been ordered according to their desorption temperature.•Interactions among mercury compounds have been evaluated.
The phasing out of leaded gasoline in many countries around the world at the end of the last millennium has resulted in a complex mixture of lead sources in the atmosphere. Recent studies suggest ...that coal combustion has become an important source of Pb in aerosols in urban and remote areas. Here, we report lead concentration and isotopic composition for 59 coal samples representing major coal deposits worldwide in an attempt to characterize this potential source. The average concentration in these coals is 35 μg Pb g−1, with the highest values in coals from Spain and Peru and the lowest in coals from Australia and North America. The 206Pb/207Pb isotope ratios range between 1.15 and 1.24, with less radiogenic Pb in coals from Europe and Asia compared to South and North America. Comparing the Pb isotopic signatures of coals from this and previous studies with those published for Northern and Southern Hemisphere aerosols, we hypothesize that coal combustion might now be an important Pb source in China, the eastern U.S., and to some extent, in Europe but not as yet in other regions including South Africa, South America, and western U.S. This supports the notion that “old Pb pollution” from leaded gasoline reemitted into the atmosphere or long-range transport (i.e., from China to the western U.S.) is important. Comparing the isotope ratios of the coals, the age of the deposits, and Pb isotope evolution models for the major geochemical reservoirs suggests that the PbIC in coals is strongly influenced by the depositional coal forming environment.
Overweight and obesity have become a world-health public problem, mainly for developing countries. Both health conditions have a higher prevalence among women of childbearing age. Physiopathology, ...overweight and obesity are characterized by a chronic oxidative stress status, which has deleterious effects on mothers and children. Hence, we determine whether the qualities of diet during pregnancy and maternal pregestational body mass index (BMI) are associated with increased oxidative stress markers in mothers and newborns. Two hundred forty-two (242) mother-newborn pairs were classified according to their pregestational BMI. Information on food intake was collected using a food frequency questionnaire in the third trimester of pregnancy. Levels of Malondialdehyde (MDA) and Nitric Oxide (NO) were measured in plasma from mothers at the end of the third trimester of pregnancy and from cord blood at birth. MDA and NO levels in mother-newborn pairs with maternal pregestational overweight or obesity were higher than in mother-newborn pairs with pregestational normal weight. For women (and newborns) who had a higher intake of fruit and vegetables, the levels of NO and MDA were lower. Lastly, women with pregestational obesity had lower fruit and vegetable intake during pregnancy and higher levels of oxidative stress and in their newborns.
Abstract
Pines are the dominant conifers in Mediterranean forests. As long-lived sessile organisms that seasonally have to cope with drought periods, they have developed a variety of adaptive ...responses. However, during last decades, highly intense and long-lasting drought events could have contributed to decay and mortality of the most susceptible trees. Among conifer species,
Pinus pinaster
Ait. shows remarkable ability to adapt to different environments. Previous molecular analysis of a full-sib family designed to study drought response led us to find active transcriptional activity of stress-responding genes even without water deprivation in tolerant genotypes. To improve our knowledge about communication between above- and below-ground organs of maritime pine, we have analyzed four graft-type constructions using two siblings as rootstocks and their progenitors, Gal 1056 and Oria 6, as scions. Transcriptomic profiles of needles from both scions were modified by the rootstock they were grafted on. However, the most significant differential gene expression was observed in drought-sensitive Gal 1056, while in drought-tolerant Oria 6, differential gene expression was very much lower. Furthermore, both scions grafted onto drought-tolerant rootstocks showed activation of genes involved in tolerance to abiotic stress, and is most remarkable in Oria 6 grafts where higher accumulation of transcripts involved in phytohormone action, transcriptional regulation, photosynthesis and signaling has been found. Additionally, processes, such as those related to secondary metabolism, were mainly associated with the scion genotype. This study provides pioneering information about rootstock effects on scion gene expression in conifers.
Objectives
To propose national diagnostic reference levels (DRLs) for interventional radiology and to evaluate the impact of the procedural complexity on patient doses.
Methods
Eight interventional ...radiology units from Spanish hospitals were involved in this project. The participants agreed to undergo common quality control procedures for X-ray systems. Kerma area product (KAP) was collected from a sample of 1,649 procedures. A consensus document established the criteria to evaluate the complexity of seven types of procedures. DRLs were set as the 3rd quartile of KAP values.
Results
The KAP (3rd quartile) in Gy cm
2
for the procedures included in the survey were: lower extremity arteriography (n = 784) 78; renal arteriography (n = 37) 107; transjugular hepatic biopsies (THB) (n = 30) 45; biliary drainage (BD) (n = 314) 30; uterine fibroid embolization (UFE) (n = 56) 214; colon endoprostheses (CE) (n = 31) 169; hepatic chemoembolization (HC) (n = 269) 303; femoropopliteal revascularization (FR) (n = 62) 119; and iliac stent (n = 66) 170. The complexity involved the increases in the following KAP factors from simple to complex procedures: THB x4; BD x13; UFE x3; CE x3; HC x5; FR x5 and IS x4.
Conclusions
The evaluation of the procedure complexity in patient doses will allow the proper use of DRLs for the optimization of interventional radiology.
Key Points
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National DRLs for interventional procedures have been proposed given level of complexity
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For clinical audits, the level of complexity should be taken into account.
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An evaluation of the complexity levels of the procedure should be made.
The irrigate district of Usosaldaña, an important agricultural area in Colombia mainly devoted to rice crop production, is subjected to an intensive use of pesticides. Monitoring these compounds is ...necessary to know the impact of phytosanitary products in the different environmental compartments. In this work, surface water and soil samples from different sites of this area have been analyzed by applying an analytical methodology for large screening based on the use of time-of-flight mass spectrometry (TOF MS) hyphenated to liquid chromatography (LC) and gas chromatography (GC). Several pesticides were detected and unequivocally identified, such as the herbicides atrazine, diuron or clomazone. Some of their main metabolites and/or transformation products (TPs) like deethylatrazine (DEA), deisopropylatrazine (DIA) and 3,4-dichloroaniline were also identified in the samples. Among fungicides, carbendazim, azoxystrobin, propiconazole and epoxiconazole were the most frequently detected. Insecticides such as thiacloprid, or p,p′-DDT metabolites (p,p′-DDD and p,p′-DDE) were also found. Thanks to the accurate-mass full-spectrum acquisition in TOF MS it was feasible to widen the number of compounds to be investigated to other families of contaminants. This allowed the detection of emerging contaminants, such as the antioxidant 3,5-di-tertbutyl-4-hydroxy-toluene (BHT), its metabolite 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), or the solar filter benzophenone, among others.
► TOF MS hyphenated to LC and GC allows large screening of many organic pollutants. ► Surface waters and soils from a Colombian agricultural area were analyzed by TOF MS. ► Several pesticides and metabolites were detected and unequivocally identified. ► Accurate-mass full-spectrum data allowed the detection of emerging contaminants.
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•The incorporation of POTE and gold nanoparticles decrease the optical band gap compared to bare chitosan film.•The incorporation gold atom trends to vary of electronic density and ...electrostatic potential of the FMOs.•The surface potential is slightly enhanced for CS/POTE/AuNPs films in comparison to that of CS/POTE films, and electronic activity displays a better distribution on the film surfaces.•Notable changes were revealed in the topography and crystallinity of the films and in the size and shape of gold nanoparticles.
Biobased films consisting of blends of chitosan with poly(octanoic acid 2-thiophen-3-yl-ethyl ester) (POTE), a conducting polymer, and gold nanoparticles (AuNPs) were prepared, and their thermal, morphological and surface potential properties were studied. POTE was dissolved in THF and mixed with an acidified aqueous solution containing chitosan to obtain chitosan/POTE (CS/POTE) films by solution casting. To produce gold nanoparticles in the CS/POTE films (i.e., CS/POTE/AuNP films), an aqueous solution of KAuCl4 salt at fixed concentration was added to the initial chitosan solution. The fabricated biobased films were characterized by spectroscopic techniques (FT-IR and UV–visible), thermogravimetry, contact angle analysis, polarized light microscopy (PLM), field emission scanning electron microscope (FE-SEM) and scanning Kelvin probe force microscopy (SKPFM). The effects of varying POTE composition and the presence of gold nanoparticles in the films were analyzed. For example, the results indicated the existence of interactions between chitosan and POTE, and LPM studies revealed a predominantly amorphous nature of these biobased films. In addition, the optical and surface potential behaviors of the films were examined by UV–visible and KPFM techniques. From the UV–visible spectra, the optical band gaps were estimated for the samples, and their surface potential maps exhibited differences according to the composition of POTE and the presence of AuNPs. Finally, theoretical electronic calculations provided insight into the contributions of POTE and gold nanoparticles to the electronic activity of the films.
•Thermal desorption as promising technique for Hg speciation in solids.•Comparison to results obtained by a sequential extraction method.•HgS was the main Hg species found in fly ashes from a ...fluidized bed.•In the soils HgS was the main species identified.
The speciation of mercury is currently attracting widespread interest because the emission, transport, deposition and behaviour of toxic mercury species depend on its chemical form. The identification of these species in low concentrations is no easy task and it is even more complex in coal combustion products due to the fact that these products contain organic and mineral matter that give rise to broad peaks and make it difficult to carry out qualitative and quantitative analysis. In this work, a solution to this problem is proposed using a method based on thermal desorption. A sequential extraction procedure was employed for the comparison and validation of the method developed. Samples of fly ashes and soils were analyzed by both of these methods, and thermal desorption was found to be an appropriate technique for mercury speciation. Even in the case of low mercury contents, recovery percentages were close to 100%. The main mercury species identified in the samples studied were HgS and, to a lesser extent, HgO and HgSO4. In addition, although the presence of mercury complexes cannot be demonstrated, the desorption behaviour and sequential extraction results suggest that this element might be associated with the mineral matrix or with carbon particles in some of the solids.
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