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1.
Dis Aquat Organ ; 159: 15-27, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087616

RESUMEN

The chytrid Batrachochytrium dendrobatidis (Bd) is a widespread fungus causing amphibian declines across the globe. Although data on Bd occurrence in Eastern Europe are scarce, a recent species distribution model (SDM) for Bd reported that western and north-western parts of Ukraine are highly suitable to the pathogen. We verified the SDM-predicted range of Bd in Ukraine by sampling amphibians across the country and screening for Bd using qPCR. A total of 446 amphibian samples (tissue and skin swabs) from 11 species were collected from 36 localities. We obtained qPCR-positive results for 33 samples including waterfrogs (Pelophylax esculentus complex) and fire- and yellow-bellied toads (Bombina spp.) from 8 localities. We found that Bd-positive localities had significantly higher predicted Bd habitat suitability than sites that were pathogen-free. Amplification and sequencing of the internal transcribed spacer (ITS) region of samples with the highest Bd load revealed matches with ITS haplotypes of the globally distributed BdGPL strain, and a single case of the BdASIA-2/BdBRAZIL haplotype. We found that Bd was non-randomly distributed across Ukraine, with infections present in the western and north-central forested peripheries of the country with a relatively cool, moist climate. On the other hand, our results suggest that Bd is absent or present in low abundance in the more continental central, southern and eastern regions of Ukraine, corroborating the model-predicted distribution of chytrid fungus. These areas could potentially serve as climatic refugia for Bd-susceptible amphibian hosts.


Asunto(s)
Batrachochytrium , Micosis , Ucrania/epidemiología , Animales , Micosis/veterinaria , Micosis/epidemiología , Micosis/microbiología , Batrachochytrium/genética , Batrachochytrium/aislamiento & purificación , Anfibios/microbiología , Modelos Biológicos , Quitridiomicetos/aislamiento & purificación , Quitridiomicetos/genética
2.
PLoS One ; 19(3): e0300135, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38547109

RESUMEN

Peptides present an alternative modality to immunoglobulin domains or small molecules for developing therapeutics to either agonize or antagonize cellular pathways associated with diseases. However, peptides often suffer from poor chemical and physical stability, limiting their therapeutic potential. Disulfide-constrained peptides (DCP) are naturally occurring and possess numerous desirable properties, such as high stability, that qualify them as drug-like scaffolds for peptide therapeutics. DCPs contain loop regions protruding from the core of the molecule that are amenable to peptide engineering via direct evolution by use of phage display technology. In this study, we have established a robust platform for the discovery of peptide therapeutics using various DCPs as scaffolds. We created diverse libraries comprising seven different DCP scaffolds, resulting in an overall diversity of 2 x 1011. The effectiveness of this platform for functional hit discovery has been extensively evaluated, demonstrating a hit rate comparable to that of synthetic antibody libraries. By utilizing chemically synthesized and in vitro folded peptides derived from selections of phage displayed DCP libraries, we have successfully generated functional inhibitors targeting the HtrA1 protease. Through affinity maturation strategies, we have transformed initially weak binders against Notch2 with micromolar Kd values to high-affinity ligands in the nanomolar range. This process highlights a viable hit-to-lead progression. Overall, our platform holds significant potential to greatly enhance the discovery of peptide therapeutics.


Asunto(s)
Disulfuros , Péptidos , Péptidos/farmacología , Péptidos/química , Biblioteca de Péptidos , Péptido Hidrolasas
3.
J Matern Fetal Neonatal Med ; 37(1): 2326303, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38503546

RESUMEN

OBJECTIVE: This study aimed to assess the impact of micronized progesterone (VMP4) supplementation on pregnancies with low serum pregnancy-associated plasma protein-A (PAPP-A) multiples of the median (MoM) values during first-trimester screening. METHODS: Out of 8933 patients evaluated, 116 pregnant women with low PAPP-A concentrations in their blood and no fetal chromosomal anomalies (CAs) were included. Three groups were formed: group 1 received VMP4 from 11 to 16 weeks (29 women, 25%), group 2 received VMP4 from 11 to 36 weeks (25 women, 21.5%), and group 3 (62 women, 53.5%) served as controls without receiving progesterone. RESULTS: Results indicated that group 3 had higher rates of complications, including miscarriages (16.37%), preterm delivery (17.8%), and fetal developmental abnormalities (19.4%). Birthweight variations were elevated in pregnancies without progesterone, contrasting with lower variations in VMP4 groups. Group 2, receiving VMP4 until 36 weeks, reported the lowest incidence of abortion and preterm birth (PB), along with the highest mean birth weight. CONCLUSIONS: The conclusion suggests that 200 mg per day of VMP4 up to 36 weeks of supplementation led to fewer placental-related complications in women with very low PAPP-A at first-trimester screening (0.399 MoM). By reporting lower rates of miscarriages, PBs, and fetal developmental abnormalities in the micronized progesterone-treated groups, the study suggests a potential reduction in complications.


Asunto(s)
Aborto Espontáneo , Nacimiento Prematuro , Embarazo , Humanos , Femenino , Recién Nacido , Primer Trimestre del Embarazo , Proteína Plasmática A Asociada al Embarazo , Aborto Espontáneo/epidemiología , Progesterona , Nacimiento Prematuro/prevención & control , Biomarcadores , Placenta
4.
Sci Signal ; 17(819): eabn1101, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227684

RESUMEN

Ubiquitination is a posttranslational modification that is crucial for the dynamic regulation of diverse signaling pathways. To enhance our understanding of ubiquitination-mediated signaling, we generated a new class of bispecific antibodies that combine recognition of ubiquitination substrates and specific polyubiquitin linkages. RIP1-K63 and RIP1-linear (Lin) linkage polyubiquitin bispecific antibodies detected linkage-specific ubiquitination of the proinflammatory kinase RIP1 in cells and in tissues and revealed RIP1 ubiquitination by immunofluorescence. Similarly, ubiquitination of the RIP1-related kinase RIP2 with K63 or linear linkages was specifically detected with the RIP2-K63 and RIP2-Lin bispecific antibodies, respectively. Furthermore, using the RIP2-K63 and RIP2-Lin bispecific antibodies, we found prominent K63-linked and linear RIP2 ubiquitination in samples from patients with ulcerative colitis and Crohn's disease. We also developed a bispecific antibody (K63-Lin) that simultaneously recognizes K63-linked and linear ubiquitination of components of various signaling pathways. Together, these bispecific antibodies represent a new class of reagents with the potential to be developed for the detection of inflammatory biomarkers.


Asunto(s)
Anticuerpos Biespecíficos , Ubiquitina , Humanos , Anticuerpos Biespecíficos/metabolismo , Poliubiquitina/metabolismo , Transducción de Señal/fisiología , Ubiquitina/metabolismo , Ubiquitinación
5.
Int J Mol Sci ; 24(11)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37298362

RESUMEN

The performance of lithium-ion batteries (LIBs) relies on the characteristics of the cathode material, including both intentionally applied coatings and naturally formed surface layers or binder adhesion. This study investigated the influence of the ion-permeable surface fraction, distribution, and characteristics of the coating on the performance of a lithium iron phosphate (LFP) electrode material. We developed an extended Newman-type half-cell model and examined the impact of coating parameters on the galvanostatic discharge curves of the LFP electrode material. The study found that the ion-permeable surface fraction has a significant influence on the diffusion and charge transfer characteristics of the electrode material. A decrease in the ion-permeable surface fraction leads to a decrease in the measured diffusion coefficients and to an increase in the overall coating resistance of the electrode material. Interestingly, the distribution of the ion-permeable surface also plays a role in the diffusion characteristics, with a coarsely dispersed coating resulting in lower diffusion coefficients. Additionally, the coating characteristics significantly affect the polarization and capacity of the electrode material at different C-rates. The model was used to approximate the experimental discharge curves of the LFP-based composite electrodes with two different compositions, and the simulated data showed satisfactory agreement with the experiment. Thus, we believe that the developed model and its further extension will be useful in numerical simulations that aim to facilitate the search for optimal compositions.


Asunto(s)
Líquidos Corporales , Litio , Difusión , Suministros de Energía Eléctrica , Electrodos , Iones
6.
ACS Omega ; 7(29): 24973-24981, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35910105

RESUMEN

This article presents new possibilities of using thin films of lanthanide stearates as sorbent materials. Modification of the Q-sense device resonator with monolayers of lanthanide stearates by the Langmuir-Schaeffer method made it possible to study the process of insulin protein adsorption on the surface of new thin-film sorbents. The resulting films were also characterized by compression isotherms, chemical analysis, scanning electron microscopy, and mass spectrometry. The transition of stearic acid to salt was recorded by IR spectroscopy. Using the LDI MS method, the main component of thin films, lanthanide distearate, was established. The presence of Eu2+ in thin films was revealed. In the case of europium stearate, the maximum value of insulin adsorption was obtained, -1.67·10-10 mole/cm2. The findings suggest the possibility of using thin films of lanthanide stearates as a sorption material for the proteomics determination of the quantitative protein content in complex fluid systems by specific adsorption on modified surfaces and isolation of such proteins from complex mixtures.

7.
Int J Mol Sci ; 24(1)2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36614158

RESUMEN

This study aims to improve properties of Ultem® polyetherimide (PEI) by incorporating up to 2 wt% additives of the perovskite oxide La0.85Yb0.15AlO3 (LYA). The structure of dense PEI/LYA films was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in combination with an analysis of their elemental composition using energy-dispersive spectroscopy (EDS). The PEI/LYA films exhibit a two-layer structure. Contact angle measurements revealed hydrophilization of the membrane surface enriched with the perovskite. The transport properties were tested via gas separation and pervaporation processes. The separation selectivity of He/N2 and O2/N2 gas pairs increased with the growth of the LYA content in the membranes. Pervaporation of a methanol(MeOH)-cyclohexane(CH) mixture was effective due to the high sorption of MeOH in the PEI/LYA membranes. The maximal pervaporation separation index was found for the PEI/LYA(2%) membrane.


Asunto(s)
Membranas Artificiales , Óxidos , Polímeros/química
8.
Sci Adv ; 7(7)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33568485

RESUMEN

A major quest in Mars' exploration has been the hunt for atmospheric gases, potentially unveiling ongoing activity of geophysical or biological origin. Here, we report the first detection of a halogen gas, HCl, which could, in theory, originate from contemporary volcanic degassing or chlorine released from gas-solid reactions. Our detections made at ~3.2 to 3.8 µm with the Atmospheric Chemistry Suite and confirmed with Nadir and Occultation for Mars Discovery instruments onboard the ExoMars Trace Gas Orbiter, reveal widely distributed HCl in the 1- to 4-ppbv range, 20 times greater than previously reported upper limits. HCl increased during the 2018 global dust storm and declined soon after its end, pointing to the exchange between the dust and the atmosphere. Understanding the origin and variability of HCl shall constitute a major advance in our appraisal of martian geo- and photochemistry.

9.
Curr Issues Personal Psychol ; 9(1): 37-45, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-38013700

RESUMEN

BACKGROUND: The main research question of the article is how the perception of help and the style of interpersonal relations are connected. In a broad sense, the question refers to the problem of constant and situational variables of prosocial activity. The main methodological framework is Vygotsky's cultural-historical psychology, in particular, the mechanism of interiorization and the interaction of interpsychological and intrapsychological processes. PARTICIPANTS AND PROCEDURE: Over 215 participants (students attending school and university, living in Ukraine, aged from 12 to 22 years) took part in our experiment, but because not all of them completed all the necessary forms correctly, only 193 participants' answers were further analyzed. Our two research techniques were Leary's Interpersonal Behavior Circle Personal Inventory and the semantic differential (N = 193). RESULTS: Each disposition from Leary's questionnaire had at least one significant correlation with the way Ukrainian adolescents perceive help. The semantic aspects of perceiving help were investigated with the help of ranking the qualities of the semantic differential for the words "help the other". CONCLUSIONS: The identified correlations contribute to the psychological analysis of the detailed characteristics of perceiving help concerning personal dispositions. Personal, communicational and semantic aspects of help are interconnected and their further research can bring rich insights.

10.
Science ; 367(6475): 297-300, 2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31919130

RESUMEN

The loss of water from Mars to space is thought to result from the transport of water to the upper atmosphere, where it is dissociated to hydrogen and escapes the planet. Recent observations have suggested large, rapid seasonal intrusions of water into the upper atmosphere, boosting the hydrogen abundance. We use the Atmospheric Chemistry Suite on the ExoMars Trace Gas Orbiter to characterize the water distribution by altitude. Water profiles during the 2018-2019 southern spring and summer stormy seasons show that high-altitude water is preferentially supplied close to perihelion, and supersaturation occurs even when clouds are present. This implies that the potential for water to escape from Mars is higher than previously thought.

11.
Nature ; 568(7753): 517-520, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30971829

RESUMEN

The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today1. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations2-5. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere6,7, which-given methane's lifetime of several centuries-predicts an even, well mixed distribution of methane1,6,8. Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections2,4. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater4 would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.

12.
Nature ; 568(7753): 521-525, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30971830

RESUMEN

Global dust storms on Mars are rare1,2 but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere3, primarily owing to solar heating of the dust3. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars4. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes5,6, as well as a decrease in the water column at low latitudes7,8. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H2O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals3. The observed changes in H2O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.

15.
Mol Cell ; 69(4): 551-565.e7, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29452636

RESUMEN

Inflammatory responses mediated by NOD2 rely on RIP2 kinase and ubiquitin ligase XIAP for the activation of nuclear factor κB (NF-κB), mitogen-activated protein kinases (MAPKs), and cytokine production. Herein, we demonstrate that selective XIAP antagonism blocks NOD2-mediated inflammatory signaling and cytokine production by interfering with XIAP-RIP2 binding, which removes XIAP from its ubiquitination substrate RIP2. We also establish that the kinase activity of RIP2 is dispensable for NOD2 signaling. Rather, the conformation of the RIP2 kinase domain functions to regulate binding to the XIAP-BIR2 domain. Effective RIP2 kinase inhibitors block NOD2 signaling by disrupting RIP2-XIAP interaction. Finally, we identify NOD2 signaling and XIAP-dependent ubiquitination sites on RIP2 and show that mutating these lysine residues adversely affects NOD2 pathway signaling. Overall, these results reveal a critical role for the XIAP-RIP2 interaction in NOD2 inflammatory signaling and provide a molecular basis for the design of innovative therapeutic strategies based on XIAP antagonists and RIP2 kinase inhibitors.


Asunto(s)
Aminoquinolinas/farmacología , Inflamación/prevención & control , Proteína Adaptadora de Señalización NOD2/antagonistas & inhibidores , Dominios y Motivos de Interacción de Proteínas/efectos de los fármacos , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor/metabolismo , Sulfonas/farmacología , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Animales , Células Cultivadas , Humanos , Inflamación/metabolismo , Inflamación/patología , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteína Adaptadora de Señalización NOD2/metabolismo , Fosforilación , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor/antagonistas & inhibidores , Transducción de Señal , Ubiquitina/metabolismo , Ubiquitinación , Proteína Inhibidora de la Apoptosis Ligada a X/antagonistas & inhibidores
16.
Astrobiology ; 17(6-7): 542-564, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28731817

RESUMEN

ISEM (Infrared Spectrometer for ExoMars) is a pencil-beam infrared spectrometer that will measure reflected solar radiation in the near infrared range for context assessment of the surface mineralogy in the vicinity of the ExoMars rover. The instrument will be accommodated on the mast of the rover and will be operated together with the panoramic camera (PanCam), high-resolution camera (HRC). ISEM will study the mineralogical and petrographic composition of the martian surface in the vicinity of the rover, and in combination with the other remote sensing instruments, it will aid in the selection of potential targets for close-up investigations and drilling sites. Of particular scientific interest are water-bearing minerals, such as phyllosilicates, sulfates, carbonates, and minerals indicative of astrobiological potential, such as borates, nitrates, and ammonium-bearing minerals. The instrument has an ∼1° field of view and covers the spectral range between 1.15 and 3.30 µm with a spectral resolution varying from 3.3 nm at 1.15 µm to 28 nm at 3.30 µm. The ISEM optical head is mounted on the mast, and its electronics box is located inside the rover's body. The spectrometer uses an acousto-optic tunable filter and a Peltier-cooled InAs detector. The mass of ISEM is 1.74 kg, including the electronics and harness. The science objectives of the experiment, the instrument design, and operational scenarios are described. Key Words: ExoMars-ISEM-Mars-Surface-Mineralogy-Spectroscopy-AOTF-Infrared. Astrobiology 17, 542-564.

17.
J Chromatogr A ; 1513: 140-148, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28750732

RESUMEN

In this research, a novel IMAC sorbent with high specificity for chlorine-containing compounds was developed. Ni-functionalized monodisperse spherical mesoporous silica particles of 500±25nm diameter were synthesized and their metal affinity properties were studied with the use of diclofenac as the model substance. The particles were aggregatively stable in the pH range of 3-12. The sorbent demonstrated a high adsorption capacity (0.60±0.06µg of DCF per 1mg of the sorbent) and high adsorption/desorption rate (20 and 5min was enough for the sorbent saturation and desorption of DCF, correspondingly). A mixture of eluents with addition of PFOS providing the almost complete recovery (98%) of diclofenac was first proposed. The monodispersity and the high sedimentation and aggregative stability of the particles provide the formation of a stable hydrosol even under ultrasound treatment which makes the mSiO2/Ni particles suitable for batch chromatography.


Asunto(s)
Cromatografía de Afinidad/métodos , Metales/química , Níquel/química , Tamaño de la Partícula , Dióxido de Silicio/química , Adsorción , Ácido Benzoico/análisis , Ciprofloxacina/análisis , Diclofenaco/análisis , Cinética , Microscopía Electrónica de Transmisión , Porosidad , Espectrometría por Rayos X , Temperatura , Factores de Tiempo
18.
Appl Opt ; 54(11): 3315-22, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25967319

RESUMEN

A new compact satellite spectrometer dedicated to monitoring terrestrial atmospheric ozone (ozonometer) is in preparation for the Russian Geophysics Program. Four instruments at four satellites (Ionosphere) are intended to monitor the total ozone content by measuring spectra of scattered solar radiation in nadir. The spectrometer is based on the Rowland scheme with a concave holographic diffraction grating. It covers the near UV and visible range of the spectrum, 300-500 nm, with a spectral resolution of ∼0.3 nm. At present, a qualification model has been manufactured and tested. We introduce the description of the instrument and the results of laboratory and ground-based atmospheric calibrations. The ozone amount retrieved from atmospheric measurements using the differential optical absorption spectroscopy (DOAS) method is in good agreement with that measured by the collocated Brewer spectrophotometer and ozone monitoring instrument on board the Aura satellite.

20.
Opt Express ; 21(15): 18354-60, 2013 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-23938707

RESUMEN

Acousto-optic tunable filter (AOTF) spectrometers are being criticized for spectral leakage, distant side lobes of their spectral response function (SRF), or the stray light. SPICAM-IR is the AOTF spectrometer in the range of 1000-1700 nm with a resolving power of 1800-2200 operating on the Mars Express interplanetary probe. It is primarily dedicated to measurements of water vapor in the Martian atmosphere. SPICAM H(2)O retrievals are generally lower than simultaneous measurements with other instruments, the stray light suggested as a likely explanation. We report the results of laboratory measurements of water vapor in quantity characteristic for the Mars atmosphere (2-15 precipitable microns) with the Flight Spare model of SPICAM-IR. We simulated the measured spectra with HITRAN-based synthetic model, varying the water abundance, and the level of the stray light, and compared the results to the known amount of water in the cell. The retrieved level of the stray light, assumed uniformly spread over the spectral range, is below 1-1.3·10(-4). The stray may be responsible for the underestimation of water abundance of up to 8%, or 0.6 pr. µm. The account for the stray light removes the bias completely; the overall accuracy to measure water vapor is ~0.2 pr. µm. We demonstrate that the AOTF spectrometer dependably measures the water abundance and can be employed as an atmospheric spectrometer.


Asunto(s)
Artefactos , Atmósfera/análisis , Atmósfera/química , Marte , Tecnología de Sensores Remotos/instrumentación , Nave Espacial/instrumentación , Análisis Espectral/instrumentación , Radiación de Fondo , Diseño de Equipo , Análisis de Falla de Equipo , Luz
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