Exploring pressure effects on metallic nanoparticles and surrounding media through plasmonic sensing

The sensing capabilities of gold nanorods under high-pressure conditions were investigated in methanol-ethanol mixtures (up to 13 GPa) and in water (up to 9 GPa) through their optical extinction. The longitudinal SPR band of AuNR exhibits a redshift with pressure which is the result of two main competing effects: compression of the conduction electrons which increases the bulk plasma frequency (blueshift) and increase in the solvent density (redshift). The variation in de SPR peak wavelength allows us to estimate the bulk modulus of the gold nanoparticles with a precision of 10 % and to obtain analytical functions providing the pressure dependence of the refractive index of water in three phases: liquid, ice VI and ice VII. Furthermore, the SPR band shows abrupt jumps at the liquid to ice phase VI and ice phase VII transitions, which are in accordance with the first-order character of these transitions.Financial support from Project PGC2018-101464-B-I00 (FEDER) and MALTA-Consolider Team (RED2018-102612-T) of the Ministerio de Ciencia, Innovación y Universidades is acknowledged

Transfer hydrogenation catalysis in cells as a new approach to anticancer drug design

Organometallic complexes are effective hydrogenation catalysts for organic reactions. For example, Noyori-type ruthenium complexes catalyse reduction of ketones by transfer of hydride from ​formate. Here we show that such catalytic reactions can be achieved in cancer cells, offering a new strategy for the design of safe metal-based anticancer drugs. The activity of ruthenium(II) sulfonamido ethyleneamine complexes towards human ovarian cancer cells is enhanced by up to 50 × in the presence of low non-toxic doses of ​formate. The extent of conversion of coenzyme ​NAD+ to ​NADH in cells is dependent on ​formate concentration. This novel reductive stress mechanism of cell death does not involve apoptosis or perturbation of mitochondrial membrane potentials. In contrast, iridium cyclopentadienyl catalysts cause cancer cell death by oxidative stress. Organometallic complexes therefore have an extraordinary ability to modulate the redox status of cancer cells

Lack of linkages among fruiting depth, weight, and maturity in irrigated truffle fungi marks the complexity of relationships among morphogenetic stages

The highly prized black truffle (Tuber melanosporum) has become a model species for ectomycorrhizal fungi biology. However, several questions concerning its reproductive phase remain unanswered. To provide new hypotheses on the fruitbody formation process, we have explored the causal links among development characters of black truffle fruitbodies that are primarily linked to either the mating process, fruitbody growing stage, or maturation. Path analysis was applied to test causal models outlining the relationships among fruitbody development characters such as fruiting depth, weight, shape, and spore maturity. These characters were investigated over a two-season survey and three soil typologies (plus peat-based substrate) under irrigated conditions. We found a clear and generalized relationship between fruitbody weight and shape. Among clusters of fruitbodies we found a positive relationship between the weight of the largest fruitbody and the weight of the remaining fruitbodies. However, no generalized relationships among characters linked to different development stages appeared. Our results were noticeably consistent across soil typologies, both for fruitbodies growing singly and in clusters, indicating that early-developing fruitbody characters did not influence characters linked to subsequent morphogenetic stages. The lack of links among stages opens new perspectives for pre-harvest quality management with stage-specific cultivation practices

Interaction of the chromium–iron black pigment with porcelanised stoneware

A study has been undertaken on the interaction between the (Fe,Cr)2O3 black pigment and an industrial porcelanised stoneware composition at its firing temperature. The results indicate that the glassy phase that forms during firing preferentially extracts Fe2O3 from the pigment and probably contributes some Al2O3 to it, enriching the pigment composition in Cr2O3, without changing pigment crystal structure. The pigment alteration process mainly affects porcelanised stoneware microstructure and, to a lesser extent, color

Half-sandwich rhodium(III) transfer hydrogenation catalysts : reduction of NAD+ and pyruvate, and antiproliferative activity

Organometallic complexes have the potential to behave as catalytic drugs. We investigate here Rh(III) complexes of general formula [(Cpx)Rh(N,N′)(Cl)], where N,N′ is ethylenediamine (en), 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen) or N-(2-aminoethyl)-4-(trifluoromethyl)benzenesulfonamide (TfEn), and Cpx is pentamethylcyclopentadienyl (Cp*), 1-phenyl-2,3,4,5-tetramethylcyclopentadienyl (CpxPh) or 1-biphenyl-2,3,4,5-tetramethyl cyclopentadienyl (CpxPhPh). These complexes can reduce NAD+ to NADH using formate as a hydride source under biologically-relevant conditions. The catalytic activity decreased in the order of N,N-chelated ligand bpy > phen > en with Cp* as the η5-donor. The en complexes (1–3) became more active with extension to the CpX ring, whereas the activity of the phen (7–9) and bpy (4–6) compounds decreased. [Cp*Rh(bpy)Cl]+ (4) showed the highest catalytic activity, with a TOF of 37.4 ± 2 h− 1. Fast hydrolysis of the chlorido complexes 1–10 was observed by 1H NMR (< 10 min at 310 K). The pKa* values for the aqua adducts were determined to be ca. 8–10. Complexes 1–9 also catalysed the reduction of pyruvate to lactate using formate as the hydride donor. The efficiency of the transfer hydrogenation reactions was highly dependent on the nature of the chelating ligand and the Cpx ring. Competition reactions between NAD+ and pyruvate for reduction by formate catalysed by 4 showed a preference for reduction of NAD+. The antiproliferative activity of complex 3 towards A2780 human ovarian cancer cells increased by up to 50% when administered in combination with non-toxic doses of formate, suggesting that transfer hydrogenation can induce reductive stress in cancer cells

Parvalbumin interneurons are differentially connected to principal cells in inhibitory feedback microcircuits along the dorso-ventral axis of the medial entorhinal cortex

The medial entorhinal cortex (mEC) shows a high degree of spatial tuning, predominantly grid cell activity, which is reliant on robust, dynamic inhibition provided by local interneurons (INs). In fact, feedback inhibitory microcircuits involving fast-spiking parvalbumin (PV) basket cells (BCs) are believed to contribute dominantly to the emergence of grid cell firing in principal cells (PrCs). However, the strength of PV BC-mediated inhibition onto PrCs is not uniform in this region, but high in the dorsal and weak in the ventral mEC. This is in good correlation with divergent grid field sizes, but the underlying morphologic and physiological mechanisms remain unknown. In this study, we examined PV BCs in layer (L)2/3 of the mEC characterizing their intrinsic physiology, morphology and synaptic connectivity in the juvenile rat. We show that while intrinsic physiology and morphology are broadly similar over the dorsoventral axis, PV BCs form more connections onto local PrCs in the dorsal mEC, independent of target cell type. In turn, the major PrC subtypes, pyramidal cell (PC) and stellate cell (SC), form connections onto PV BCs with lower, but equal probability. These data thus identify inhibitory connectivity as source of the gradient of inhibition, plausibly explaining divergent grid field formation along this dorsoventral axis of the mEC

Estudio de cerámicas de la Edad del Bronce en yacimientos arqueológicos de la provincia de Guadalajara

En este trabajo se presenta el resultado del estudio de fragmentos cerámicos del período Eneolítico,\ud aplicando diferentes métodos analíticos (difracción de rayos X, análisis térmico, estudio petrográfico, etc.).\ud Las muestras cerámicas pertenecen a una serie de refugios de dicho período (2800-2200 años a. de c.,\ud situados en la provincia de Guadalajara, refugios de Peña Corva, Cueva Harzal, y Enebrales), recogidos\ud y estudiados por Valiente Malla y otros autores.\ud El interés de este estudio arqueométrico es el de establecer a través de la composición y característica\ud de los fragmentos cerámicos, el origen, temperatura y atmósfera de cocción y posible parecido entre\ud ellas, que establezcan conexiones entre los refugios.This paper presents the results of research on paste composition and firing of ancient ceramics\ud by applications of different analytical methods (XRD, petrographie microscope, ATG,...).\ud The samples of ceramics come from the shelters of Peña Corva in Santamera, Cueva Harzal\ud in Olmedillas and Enebrales in Tamajón (Guadalajara, Spain)... collected by Valiente Malla, J.\ud and other authors; and are according with the system stablished or the Eneolithic Period,\ud 2800-2200 years a.C. old, just as Delibes G.\ud Though the archaeoceramic analysis we intend to konw: ceramics composition, process of\ud firing and temperature, firing atmosphere, local origin, conections between the samples, and burial state activity the mineralogical change on it

Use of Placental MSCs and their exosomes as theragnostic agents for cancer treatment and diagnostic

P117 INTRODUCTION: The Na/ I symporter gene (hNIS) is expressed in the thyroid and allows the accumulation of iodine from the diet, to form T3 and T4 hormones. Moreover, it is widely used (i) as a reporter gene for molecular imaging (when the positron emitter isotope is I124 for PET or Tc99 for SPECT) or (ii) as a therapeutic gene for cancer therapy, mediated by the accumulation of I131. An unresolved challenge is how to direct this gene specifically to the tumoral area. Previously, our group demonstrated the migratory capacity of placental mesenchymal stem cells (MSCs), carrying an adenovirus-hNIS to tumors, with good results as theragnostic tool. However, as hNIS is expressed at the placental tissue (because transfers iodine to the foetus from the maternal blood), here we decided to study whether placental MSCs and their exosomes (1) express hNIS endogenously and therefore transfers the imaging and therapeutic potentials when administered with radioactive iodine (2) are capable to reach tumoral areas when they are intravenously injected due to the tumoral tissues extravasation. RESULTS/ SUMMARY We proved that human placenta MSCs and their exosomes have endogenous expression of NIS, migrate specifically to the tumour and their endogenous expression of NIS is enough to image both cells or exosomes in vivo, and their accumulation caused significant therapeutic effect combined with 131I. This highlight the use of endogenous NIS expression as therapy but also to trace new metastatic nodules

Function of tau protein in adult newborn neurons

AbstractLevels of tau phosphorylation are high during the developmental period of intense neurite outgrowth, but decrease later. We here investigated whether tau protein plays a role in adult neurogenesis. First we demonstrate that new neurons generated in the subgranular zone express tau in a hyperphosphorylated form. Phospho-tau expression colocalized with doublecortin but not with glial fibrillary acidic protein, Ki67 or calbindin. The same was observed in the subventricular zone. Tau knockout mice did not show a significant decrease in the number of doublecortin-positive cells, although a deficit in migration was observed. These findings suggest that basal tau phosphorylation present in adult animals is in part due to neurogenesis, and from Tau knockout mice it seems that tau is involved in normal migration of new neurons

Soil Moisture and Black Truffle Production Variability in the Iberian Peninsula

The relationship between modelled root zone soil moisture (SM) and black truffle production in the Iberian Peninsula was studied. Previous works have investigated the influence that precipitation exerts on truffle yield highlighting the importance of water for the growth of black truffle. However, SM had not been used until now due to the lack of suitable databases. The SM series from the LISFLOOD hydrological rainfall–runoff model was used in this study. Annual black truffle yield series from 175 locations in Spain was correlated with SM for the period 1991–2012. For this, different approaches were applied considering daily, weekly and monthly temporal scales. The same analysis was carried out using precipitation data to compare the behaviors of both variables related to truffle production variability. The results obtained show critical periods in terms of soil water content in summer (June–September) and during October–November months. Moreover, a clear delay between precipitation and SM influence on black truffle was observed. The results obtained in this study highlight the importance of SM for black truffle production, since this variable truly expresses the available water for this fungus, which completes its entire life cycle living below ground. © 2022 by the authors. Licensee MDPI, Basel, Switzerland