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Abstract Genes of the Sprouty family (Spry1-4) are feedback inhibitors of receptor tyrosine kinases, especially of Ret and the FGF receptors. As such, they play distinct and overlapping roles in embryo morphogenesis and are considered to be tumor suppressors in adult life. Genetic experiments in mice have defined in great detail the role of these genes during embryonic development, however their function in adult mice is less clearly established. Here we generate adult-onset, whole body Spry1/2/4 triple knockout mice. Tumor incidence in triple mutant mice is comparable to that of wild type littermates of up to one year of age, indicating that Sprouty loss per se is not sufficient to initiate tumorigenesis. On the other hand, triple knockout mice do not gain weight as they age, show less visceral fat, and have lower plasma glucose levels than wild type littermates, despite showing similar food intake and slightly reduced motor function. They also show alopecia, eyelid inflammation, and mild hyperthyroidism. Finally, triple knockout mice present phosphaturia and hypophosphatemia, suggesting exacerbated signaling downstream of FGF23. In conclusion, triple knockout mice develop a series of endocrine abnormalities but do not show increased tumor incidence.

L3-edge high-energy-resolution fluorescence-detection X-ray absorption near-edge structure (XANES) spectra for palladium and rhodium compounds are presented, with focus on their electronic structures. The data are compared with transmission XANES spectra recorded at the K-edge. A correlation between the absorption edge energy and the metal ion oxidation state is not observed. Despite the different filling of the 4d orbitals and different local coordination, the Rh and Pd compounds show remarkably similar spectral shapes. Calculation of the density of states and of the L3-XANES data reproduce the experimental results.

Abstract Genes of the Sprouty family (Spry1-4) restrain signaling by certain receptor tyrosine kinases. Consequently, these genes participate in several developmental processes and function as tumor suppressors in adult life. Despite these important roles, the biology of this family of genes still remains obscure. Here we show that Sprouty proteins are general mediators of cellular senescence. Induction of cellular senescence by several triggers in vitro correlates with upregulation of Sprouty protein levels. More importantly, overexpression of Sprouty genes is sufficient to cause premature cellular senescence, via a conserved N-terminal tyrosine (Tyrosine 53 of Sprouty1). Accordingly, fibroblasts from knockin animals lacking that tyrosine escape replicative senescence. In vivo, heterozygous knockin mice display delayed induction of cellular senescence during cutaneous wound healing and upon chemotherapy-induced cellular senescence. Unlike other functions of this family of genes, induction of cellular senescence appears to be independent of activation of the ERK1/2 pathway. Instead, we show that Sprouty proteins induce cellular senescence upstream of the p38 pathway in these in vitro and in vivo paradigms.

IntroductionBrown rot is the most important fungal disease affecting stone fruit and it is mainly caused by Monilinia fructicola, M. laxa and M. fructigena. Monilinia spp. are necrotrophic plant pathogens with the ability to induce plant cell death by the secretion of different phytotoxic molecules, including proteins or metabolites that are collectively referred to as necrotrophic effectors (NEs).MethodsWe exploited the genomes of M. fructicola, M. laxa and M. fructigena to identify their common group of secreted effector proteins and tested the ability of a selected set of effectors to induce cell death in Nicotiana benthamiana, Solanum lycopersicum and Prunus spp. leaves.ResultsFourteen candidate effector genes of M. fructicola, which displayed high expression during infection, were transiently expressed in plants by agroinfiltration using a modified Tobacco Rattle Virus (TRV)-based expression system. Some, but not all, effectors triggered leaf discoloration or cell death in N. benthamiana and S. lycopersicum, which are non-hosts for Monilinia and in Prunus spp., which are the natural hosts. The effector MFRU_030g00190 induced cell death in almost all Prunus genotypes tested, but not in the Solanaceous plants, while MFRU_014g02060, which is an ortholog to BcNep1, caused necrosis in all plant species tested.ConclusionThis method provides opportunities for screening Prunus germplasm with Monilinia effector proteins, to serve as a tool for identifying genetic loci that confer susceptibility to brown rot disease.

The Wolffian ducts (WD) are paired epithelial tubules central to the development of the mammalian genitourinary tract. Outgrowths from the WD known as the ureteric buds (UB) generate the collecting ducts of the kidney. Later during development, the caudal portion of the WD will form the vas deferens, epididymis and seminal vesicle in males, and will degenerate in females. While the genetic pathways controlling the development of the UB are firmly established, less is known about those governing development of WD portions caudal to the UB. Sprouty proteins are inhibitors of receptor tyrosine kinase (RTK) signaling in vivo. We have recently shown that homozygous mutation of a conserved tyrosine (Tyr53) of Spry1 results in UB defects indistinguishable from that of Spry1 null mice. Here, we show that heterozygosity for the Spry1 Y53A allele causes caudal WD developmental defects consisting of ectopically branched seminal vesicles in males and persistent WD in females, without affecting kidney development. Detailed analysis reveals that this phenotype also occurs in Spry1+/- mice but with a much lower penetrance, indicating that removal of tyrosine 53 generates a dominant negative mutation in vivo. Supporting this notion, concomitant deletion of one allele of Spry1 and Spry2 also recapitulates the genital phenotype of Spry1Y53A/+ mice with high penetrance. Mechanistically, we show that unlike the effects of Spry1 in kidney development, these caudal WD defects are independent of Ret signaling, but can be completely rescued by lowering the genetic dosage of Fgf10. In conclusion, mutation of tyrosine 53 of Spry1 generates a dominant negative allele that uncovers fine-tuning of caudal WD development by Sprouty genes.

The major factors affecting the in vitro immature embryo rescue efficiencies from Prunus persica or P. armeniaca accessions have been identified, along with improving the feasibility. Variations in the woody plant medium (WPM) were used depending on the embryo size. Embryos less than 5 mm long were cultured in WPM supplemented with 1 μM BAP and 1 μM GA3, while embryos bigger than 5 mm long were cultured in hormone-free medium, with or without vermiculite. The environmental in vitro culture conditions consisted of three phases: a (I) stratification at 4 °C during a 3- to 5-month-long period in the dark, followed by (II) growth of germinated embryos at 14 °C for a 4-week-long period, with 12 h light a day, which favors plantlet development, and finally, (III) growth at 24 °C, with 16 h light a day, until the plantlets were acclimatized in the greenhouse. The germination of smaller embryos, at the end of phase I, ranged from 82.2% to 22.1% for apricots and flat peaches, respectively, whereas for bigger embryos, the germination varied from 97.3% to 53.2% for the same species. The embryo germination for peaches and nectarines ranged from 40.1% to 30.3% for smaller embryos, and from 91.9% to 63.0% for bigger embryos. Endo- and epiphytic contamination, affecting from 7.4% to 52.9% of cultured embryos, depending on the fruit type and conservation conditions, and the capacity to acclimate to soil conditions, ranging from 50.4% to 93.2%, were the two most important factors influencing the protocol’s efficiency and feasibility. Considering the overall efficiencies, expressed as hardened plants transferred to field plots over clean uncontaminated embryo, the values ranged from 55.8% for nectarines, 54.0% for peaches, 45.6% for apricots, and 23.3% for flat fruits. The addition of vermiculite to the culture medium significantly improved the plantlet development, avoiding subculture to fresh medium when an extension of phase III was required before acclimatization. Compared to laboratory glassware, the use of food glass containers with air-permeable sealing film, along with vermiculite-containing medium, significantly reduced the costs when handling the large number of embryos required for breeding programs.

Metal chalcohalides are promising candidates for next-generation technologies that include energy conversion, information storage, and quantum computing. Among them, antimony selenoiodide (SbSeI) has received rising interest for different optoelectronic devices, including photovoltaics, due to its bandgap energy, strong optical absorption, stability, and earth abundant, low-cost, and low toxicity constituents. In this work, SbSeI thin films were prepared through a two-step process. At first, antimony selenide (Sb2Se3) thin films were deposited at 300 °C (Sb2Se3-300) and at room temperature (Sb2Se3-RT) onto molybdenum covered soda-lime glass substrates by a magnetron sputtering method. The formation of SbSeI thin films was performed by isothermally annealing the as-deposited Sb2Se3 thin films in sealed quartz ampoules in the atmosphere of antimony iodide (SbI3) with the presence of 100 Torr of argon pressure. The influence of the annealing temperature and time during the iodization of different types of substrates on the morphology and composition of SbSeI thin films was investigated. The well-oriented and dense single-phase SbSeI thin films with stoichiometric composition and single-crystal micro-columnar structures were achieved by annealing Sb2Se3-RT in SbI3 atmosphere at 250 °C for 5 min under 100 Torr of Ar pressure. The room temperature photoluminescence (RT-PL) of SbSeI exhibited a broad asymmetric PL band with a maximum at 1.67 eV. The low-temperature (T = 8 K) PL study of SbSeI showed a broad and asymmetric PL band at 1.4 eV, being quite distant from the bandgap. This PL band at 1.4 eV with obtained small thermal quenching activation energy of 12.7 meV is proposed to originate from the deep donor-deep acceptor pair (DD-DA) recombination.

Metformin is a widespread antidiabetic agent that is commonly used as a treatment against type 2 diabetes mellitus patients. Regarding its therapeutic potential, multiple studies have concluded that Metformin exhibits antineoplastic activity on several types of cancer, including endometrial carcinoma. Although Metformin’s antineoplastic activity is well documented, its cellular and molecular anticancer mechanisms are still a matter of controversy because a plethora of anticancer mechanisms have been proposed for different cancer cell types. In this study, we addressed the cellular and molecular mechanisms of Metformin’s antineoplastic activity by using both in vitro and in vivo studies of Pten-loss driven carcinoma mouse models. In vivo, Metformin reduced endometrial neoplasia initiated by Pten-deficiency. Our in vitro studies using Pten-deficient endometrial organoids focused on both cellular and molecular levels in Metformin’s tumor suppressive action. At cellular level, we showed that Metformin is involved in not only the proliferation of endometrial epithelial cells but also their regulation via a variety of mechanisms of epithelial-to-mesenchymal transition (EMT) as well as TGF-β-induced apoptosis. At the molecular level, Metformin was shown to affect the TGF-β signalling., a widely known signal that plays a pivotal role in endometrial carcinogenesis. In this respect, Metformin restored TGF-β-induced apoptosis of Pten-deficient endometrial organoids through a p38-dependent mechanism and inhibited TGF-β-induced EMT on no-polarized endometrial epithelial cells by inhibiting ERK/MAPK signalling. These results provide new insights into the link between the cellular and molecular mechanism for Metformin’s antineoplastic activity in Pten-deficient endometrial cancers.

The temporary immersion system bioreactor named GreenTray® presents advantages over the existing ones. Firstly, there is no need to use forceps to move the shoots or plantlets in or out of the recipient, nor is the use of a scalpel necessary to divide them. Secondly, the basis of the shoot can remain in the GreenTray® and can sprout again over several cycles of growth. These two characteristics reduce the costs in the process of micropropagation. In addition, shoot or plantlet development is enhanced by the aeration of the recipient, thus enriching the recipient’s atmospheric CO2. This article describes and provides images and values of interest in (1) the micropropagation process of some commercial Prunus or Pyrus rootstocks; (2) the plantlet growth under autotrophic conditions; and (3) the inoculation of plants with pathogens that reproduce in vitro the symptoms observed in vivo, using the GreenTray® bioreactor.

Abstract Phosphatase and TENsin homolog (Pten) and p53 are two of the most frequently mutated tumor suppressor genes in endometrial cancer. However, the functional consequences and histopathological manifestation of concomitant p53 and Pten loss of function alterations in the development of endometrial cancer is still controversial. Here, it is demonstrated that simultaneous Pten and p53 deletion is sufficient to cause epithelial to mesenchymal transition phenotype in endometrial organoids. By a novel intravaginal delivery method using HIV1 trans‐activator of transcription cell penetrating peptide fused with a Cre recombinase protein (TAT‐Cre), local ablation of both p53 and Pten is achieved specifically in the uterus. These mice developed high‐grade endometrial carcinomas and a high percentage of uterine carcinosarcomas resembling those found in humans. To further demonstrate that carcinosarcomas arise from epithelium, double Pten/p53 deficient epithelial cells are mixed with wild type stromal and myometrial cells and subcutaneously transplanted to Scid mice. All xenotransplants resulted in the development of uterine carcinosarcomas displaying high nuclear pleomorphism and metastatic potential. Accordingly, in vivo CRISPR/Cas9 disruption of Pten and p53 also triggered the development of metastatic carcinosarcomas. The results unfadingly demonstrate that simultaneous deletion of p53 and Pten in endometrial epithelial cells is enough to trigger epithelial to mesenchymal transition that is consistently translated to the formation of uterine carcinosarcomas in vivo.

Abstract The extracellular matrix and the correct establishment of epithelial cell polarity plays a critical role in epithelial cell homeostasis and cell polarity. In addition, loss of tissue structure is a hallmark of carcinogenesis. In this study, we have addressed the role of extracellular matrix in the cellular responses to TGF-β. It is well known that TGF-β is a double-edged sword: it acts as a tumor suppressor in normal epithelial cells, but conversely has tumor-promoting effects in tumoral cells. However, the factors that determine cellular outcome in response to TGF-β remain controversial. Here, we have demonstrated that the lack of extracellular matrix and consequent loss of cell polarity inhibits TGF-β-induced apoptosis, observed when endometrial epithelial cells are polarized in presence of extracellular matrix. Rather, in absence of extracellular matrix, TGF-β-treated endometrial epithelial cells display features of epithelial-to-mesenchymal transition. We have also investigated the molecular mechanism of such a switch in cellular response. On the one hand, we found that the lack of Matrigel results in increased AKT signaling which is sufficient to inhibit TGF-β-induced apoptosis. On the other hand, we demonstrate that TGF-β-induced epithelial-to-mesenchymal transition requires ERK and SMAD2/3 activation. In summary, we demonstrate that loss of cell polarity changes the pro-apoptotic function of TGF-β to tumor-associated phenotype such as epithelial-to-mesenchymal transition. These results may be important for understanding the dual role of TGF-β in normal versus tumoral cells.

Pnictogen chalcohalides are semiconductors that have emerged as promising materials for energy conversion due to their exceptional optoelectronic properties. Their electronic configuration (ns ^2 ), particularly for Bi- and Sb-based compounds, can be a key factor in efficient carrier transport and defect tolerance, similarly, to Pb-perovskites. In the present study, the Bi-containing chalcohalide, bismuth selenoiodide (BiSeI) was synthesized via isothermal heat treatment of binary precursors in evacuated quartz ampoules. The synthesized BiSeI microcrystals exhibited a characteristic needle-like morphology and a near-stoichiometric composition. Both indirect and direct band gap energies of BiSeI were determined by ultraviolet–visible–near-infrared diffuse reflectance spectroscopy, with room temperature values of 1.17 eV and 1.29 eV, respectively. This study presents the first experimental investigation of the photoluminescence properties of BiSeI microcrystals resulting in a recombination model involving multiple defect states. This work provides valuable insights into the defect structure and recombination mechanisms within BiSeI, paving the way for further exploration of its potential in optoelectronic devices.

Fire blight, caused by Erwinia amylovora, is one of the most devastating apple diseases. The selection of cultivars of low susceptibility and the study of the genetic mechanisms of the disease play important roles in fire blight management. The susceptibility level to fire blight was evaluated in 102 accessions originating from Asturias, a cider-producing region located in the north of Spain with a wide apple germplasm. Evaluations took place under quarantine conditions using artificial inoculations of grafted plants. The results revealed wide variation in susceptibility responses and low-susceptible cultivars were identified. In addition, 91 cultivars were genotyped using the Affymetrix Axiom® Apple 480 K SNP array to conduct genome-wide association studies (GWAS). A statistically significant signal was detected on chromosome 10 using the multi-locus mixed model (MLMM). Two genes were identified as major putative candidate genes: a TIR-NBS-LRR class disease protein and a protein containing a development and cell death (DCD) domain. The outcomes of this study provide a promising source of information, particularly in the context of cider apples, and set a starting point for future genetic and breeding approaches.

The major factors affecting the in vitro immature embryo rescue efficiencies from Prunus persica or P. armeniaca accessions have been identified, along with improving the feasibility. Variations in the woody plant medium (WPM) were used depending on the embryo size. Embryos less than 5 mm long were cultured in WPM supplemented with 1 μM BAP and 1 μM GA3, while embryos bigger than 5 mm long were cultured in hormone-free medium, with or without vermiculite. The environmental in vitro culture conditions consisted of three phases: a (I) stratification at 4 °C during a 3- to 5-month-long period in the dark, followed by (II) growth of germinated embryos at 14 °C for a 4-week-long period, with 12 h light a day, which favors plantlet development, and finally, (III) growth at 24 °C, with 16 h light a day, until the plantlets were acclimatized in the greenhouse. The germination of smaller embryos, at the end of phase I, ranged from 82.2% to 22.1% for apricots and flat peaches, respectively, whereas for bigger embryos, the germination varied from 97.3% to 53.2% for the same species. The embryo germination for peaches and nectarines ranged from 40.1% to 30.3% for smaller embryos, and from 91.9% to 63.0% for bigger embryos. Endo- and epiphytic contamination, affecting from 7.4% to 52.9% of cultured embryos, depending on the fruit type and conservation conditions, and the capacity to acclimate to soil conditions, ranging from 50.4% to 93.2%, were the two most important factors influencing the protocol's efficiency and feasibility. Considering the overall efficiencies, expressed as hardened plants transferred to field plots over clean uncontaminated embryo, the values ranged from 55.8% for nectarines, 54.0% for peaches, 45.6% for apricots, and 23.3% for flat fruits. The addition of vermiculite to the culture medium significantly improved the plantlet development, avoiding subculture to fresh medium when an extension of phase III was required before acclimatization. Compared to laboratory glassware, the use of food glass containers with air-permeable sealing film, along with vermiculite-containing medium, significantly reduced the costs when handling the large number of embryos required for breeding programs. [ABSTRACT FROM AUTHOR]

Abstract Nanoporosity is clearly beneficial for the performance of heterogeneous catalysts. Although exsolution is a modern method to design innovative catalysts, thus far it is predominantly studied for sintered matrices. A quantitative description of the exsolution of Ni nanoparticles from nanoporous perovskite oxides and their effective application in the biogas dry reforming is here presented. The exsolution process is studied between 500 and 900 °C in nanoporous and sintered La0.52Sr0.28Ti0.94Ni0.06O3±δ. Using temperature‐programmed reduction (TPR) and X‐ray absorption spectroscopy (XAS), it is shown that the faster and larger oxygen release in the nanoporous material is responsible for twice as high Ni reduction than in the sintered system. For the nanoporous material, the nanoparticle formation mechanism, studied by in situ TEM and small‐angle X‐ray scattering (SAXS), follows the classical nucleation theory, while on sintered systems also small endogenous nanoparticles form despite the low Ni concentration. Biogas dry reforming tests demonstrate that nanoporous exsolved catalysts are up to 18 times more active than sintered ones with 90% of CO2 conversion at 800 °C. Time‐on‐stream tests exhibit superior long‐term stability (only 3% activity loss in 8 h) and full regenerability (over three cycles) of the nanoporous exsolved materials in comparison to a commercial Ni/Al2O3 catalyst.

Background: Deslorelin implant use in cats is a medical alternative to surgical sterilization, and due to its prolonged efficacy, its use has shown growing interest in the veterinary community. In the case of breeding facilities, its removal is often requested for the early restoration of testicular function. As anti-Müllerian hormones (AMH) in males is dependent of testosterone secretion, its assay may determine the restoration of testicular steroid secretion. An average of 3 weeks has been already described for tomcats’ testicular function resumption after implant removal, but information about AMH concentrations in deslorelin-treated tomcats is lacking. Methods: Fourteen tomcats were treated for temporary suppression of fertility with a 4.7 mg deslorelin implant, which was surgically removed after 3, 6 or 9 months (n = 6, 4 and 4 tomcats, respectively). A general clinical and reproductive check with a gonadorelin stimulation test for testosterone determination was performed before deslorelin implant administration. After implant removal, tomcats’ testicles were ultrasonographically checked for volume determination every 1-2 weeks with observation of the glans penis (presence or absence of spikes) and blood collection to assay both testosterone and AMH concentrations. Results: AMH concentrations increased significantly during the deslorelin treatment from 20.95 ± 4.97 ng/mL to 82.41 ± 14.59 ng/mL (p < 0.05). Following implant removal, AMH concentrations progressively decreased to pre-treatment levels, with a value of 28.42 ± 7.98 ng/mL on the third week post-removal where testosterone secretion was again detected. Conclusions: Even if a big variability of AMH concentrations exists between male individuals, resumption of tomcats’ testicular function following a deslorelin treatment can be determined by AMH assay.

Although job quality has become an active field of study over the last two decades in developed countries, it still remains an under-discussed concept in developing regions such as Latin America, where the incidence of work informality and low wages are particularly high. As quality of employment is a multidimensional concept and not homogeneously defined in the literature, we follow a Principal Component Analysis (PCA) to build a Quality of Employment (QoE) Index for salary earners using household survey micro data of Uruguay from 2016-2019. Uruguay leads the Better Jobs Index launched by the Inter-American Development Bank in 2017, which constitutes the only index with a macro-approach to measure quantity and quality employment conditions in the region. We consider several aspects of working conditions: employment, earnings, hours worked, occupational safety and social security coverage. We focus on the tourism sector, which presents low job quality characteris-tics at the same time it accounts for 7.2% of employment in Uruguay. Furthermore, we found a sex-based gap of employment quality against women in tourism, a difference that is not observed in the trade sector. QoE in tourism shows a greater dispersion in the distribution of employees, indicating the presence of more inequalities among these workers compared to those of trade. Other results show that job quality in tourism is lower for those unskilled, but that there are still many skilled work-ers facing low quality. Finally, if we consider the activities that conform tourism, workers do better in hotels and travel agencies rather than in restaurants and entertainment.

Introduction: Brown rot is the most important fungal disease affecting stone fruit and it is mainly caused by Monilinia fructicola, M. laxa and M. fructigena. Monilinia spp. are necrotrophic plant pathogens with the ability to induce plant cell death by the secretion of different phytotoxic molecules, including proteins or metabolites that are collectively referred to as necrotrophic effectors (NEs). Methods: We exploited the genomes of M. fructicola, M. laxa and M. fructigena to identify their common group of secreted effector proteins and tested the ability of a selected set of effectors to induce cell death in Nicotiana benthamiana, Solanum lycopersicum and Prunus spp. leaves. Results: Fourteen candidate effector genes of M. fructicola, which displayed high expression during infection, were transiently expressed in plants by agroinfiltration using a modified Tobacco Rattle Virus (TRV)-based expression system. Some, but not all, effectors triggered leaf discoloration or cell death in N. benthamiana and S. lycopersicum, which are non-hosts for Monilinia and in Prunus spp., which are the natural hosts. The effector MFRU&lowbar;030g00190 induced cell death in almost all Prunus genotypes tested, but not in the Solanaceous plants, while MFRU&lowbar;014g02060, which is an ortholog to BcNep1, caused necrosis in all plant species tested. Conclusion: This method provides opportunities for screening Prunus germplasm with Monilinia effector proteins, to serve as a tool for identifying genetic loci that confer susceptibility to brown rot disease. [ABSTRACT FROM AUTHOR]

CeO2‐supported noble metal clusters are attractive catalytic materials for several applications. However, their atomic dispersion under oxidizing reaction conditions often leads to catalyst deactivation. In this study, the noble metal cluster formation threshold is rationally adjusted by using a mixed CeO2‐Al2O3 support. The preferential location of Pd on CeO2 islands leads to a high local surface noble metal concentration and promotes the in situ formation of small Pd clusters at a rather low noble metal loading (0.5 wt %), which are shown to be the active species for CO conversion at low temperatures. As elucidated by complementary in situ/operando techniques, the spatial separation of CeO2 islands on Al2O3 confines the mobility of Pd, preventing the full redispersion or the formation of larger noble metal particles and maintaining a high CO oxidation activity at low temperatures. In a broader perspective, this approach to more efficiently use the noble metal can be transferred to further systems and reactions in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

L3‐edge high‐energy‐resolution fluorescence‐detection X‐ray absorption near‐edge structure (XANES) spectra for palladium and rhodium compounds are presented, with focus on their electronic structures. The data are compared with transmission XANES spectra recorded at the K‐edge. A correlation between the absorption edge energy and the metal ion oxidation state is not observed. Despite the different filling of the 4d orbitals and different local coordination, the Rh and Pd compounds show remarkably similar spectral shapes. Calculation of the density of states and of the L3‐XANES data reproduce the experimental results. [ABSTRACT FROM AUTHOR]

This paper describes a novel low-cost tire pressure monitoring system (TPMS) for bicycles. The system is based on a battery-less near field communication (NFC) tag that integrates a pressure sensor, which is placed between the tire and the inner tube. The system uses no battery since the energy is obtained from the magnetic field induced by the reader in order to establish the communication. The pressure can be read by any NFC-enabled reader such as a smartphone. The pressure sensor is a force-sensing resistor (FSR) that controls the oscillation frequency of a 555 timer-based oscillator. The frequency is read and computed by a microcontroller, and the result is written via $\text{I}^{2}\text{C}$ bus to the memory of a near-field communication integrated circuit (IC), which is read by a commercial smartphone or NFC reader. A prototype is designed on an FR4 substrate which integrates a $12 \times 16$ mm antenna connected to the NFC IC (NT3H211 from NXP). The proposed prototype has a 3D-printed enclosure to protect the components mounted on the surface of the PCB and to protect the tire from punctures. A system for characterizing the read range is presented. The tag requires a minimum magnetic field of $2.9~A_{RMS}/m$ to operate up to a distance of 8 mm between reader and the tire, providing enough power to supply energy to the whole circuitry and to receive the information stored at the NFC IC. The system has been tested with a 59 mm-width mountain bike tire. The sensor has been characterized using a simple polynomial fitting to obtain the pressure from the measurement of the oscillation frequency. An accuracy of 0.1 has been accomplished in the range of 0.5 to 2.2 bar. To test the system, several inflation cycles have been performed and showed that the system presents good repeatability.