Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 172
Filtrar
2.
Phys Rev Lett ; 132(10): 104003, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38518309

RESUMEN

Investigating how classical systems may manifest dynamics analogous to those of quantum systems is a broad subject of fundamental interest. Walking droplets, which self-propel through a resonant interaction with their own wave field, provide a unique macroscopic realization of wave-particle duality that exhibits behaviors previously thought exclusive to quantum particles. Despite significant efforts, elucidating the precise origin and form of the wave-mediated forces responsible for the walker's quantumlike behavior remained elusive. Here, we demonstrate that, owing to wave interference, the force responsible for orbital quantization originates from waves excited near stationary points on the walker's past trajectory. Moreover, we derive a minimal model with the essential ingredients to capture quantized orbital dynamics, including quasiperiodic and chaotic orbits. Notably, this minimal model provides an explicit distinction between local forces, which account for the walker's preferred speed and wave-induced added mass, and spatiotemporal nonlocal forces responsible for quantization. The quantization mechanism revealed here is generic, and will thus play a role in other hydrodynamic quantum analogs.

3.
Eur J Contracept Reprod Health Care ; 28(2): 92-96, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36803168

RESUMEN

OBJECTIVE: To evaluate the acceptance rate of post-placental intrauterine device (PPIUD) placement during the SARS-CoV-2 (COVID-19) pandemic and to to assess factors associated with PPIUD acceptance. METHODS: A cross-sectional study was conducted between August 2020 and August 2021. PPIUDs were offered to women scheduled for caesarean delivery or admitted in labour at the Women's Hospital of the University of Campinas. The study compared women according to whether they accepted or did not accept the IUD placement. The factors associated with PPIUD acceptance were analysed through bivariate and multiple logistic regression analyses. RESULTS: We enrolled 299 women (15.9% of the deliveries that occurred during study period), aged 26.8 ± 6.5 years; 41.8% were White, almost one third were primiparous, and 155/299 (51.8%) had a vaginal delivery. The PPIUD acceptance rate was 65.6%. The principal reason for refusal was the desire for another contraceptive (41.8%). Women with the highest likelihood of accepting a PPIUD were younger (<30 years old has 1.7 more likely or 74% greater), those without a partner (3.4 times more likely) and those after vaginal delivery (1.7 times more likely or 69% greater). CONCLUSION: The COVID-19 does not affected the PPIUD placement. PPIUD is a viable alternative during crisis in which women has difficult to access health services. Younger women, those without a partner and after vaginal delivery were more likely to accept a PPIUD during the COVID-19 pandemic.


Post-placental IUDs are an alternative during periods of crisis like the COVID-19 pandemic. Younger women, those without a partner and after vaginal delivery were more likely to accept a PPIUD during the COVID-19 pandemic.


Asunto(s)
COVID-19 , Dispositivos Intrauterinos , Embarazo , Femenino , Humanos , Adulto , SARS-CoV-2 , Periodo Posparto , Pandemias , Estudios Transversales , Placenta
4.
Placenta ; 130: 1-8, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36343527

RESUMEN

Pregnancy pathologies including gestational diabetes, intrauterine fetal growth restriction, and pre-eclampsia are common and significantly increase the risk of poor pregnancy outcomes. Research to better understand the pathophysiology and improve diagnosis and treatment is therefore crucial. The ex vivo placenta perfusion model offers a unique system to study pregnancy pathology without the risk of harm to mother or fetus. The presence of a maternal and fetal circulation and intact villus tree, facilitates investigations into maternal-fetal transfer, altered hemodynamics and vascular reactivity in the human placenta. It also provides a platform to test novel therapeutic agents. Here we review the key studies which have utilized the ex vivo placenta perfusion model to study different aspects of such pregnancy pathologies.


Asunto(s)
Placenta , Preeclampsia , Embarazo , Femenino , Humanos , Placenta/irrigación sanguínea , Retardo del Crecimiento Fetal , Feto , Perfusión
5.
Front Neural Circuits ; 16: 834434, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092277

RESUMEN

The article considers the problem of dividing the encephalography data into two time series, that generated by the brain and that generated by other electrical sources located in the human head. The magnetic encephalograms and magnetic resonance images of the head were recorded in the Center for Neuromagnetism at NYU Grossman School of Medicine. Data obtained at McGill University and Montreal University were also used. Recordings were made in a magnetically shielded room and the gradiometers were designed to suppress external noise, making it possible to eliminate them from the data analysis. Magnetic encephalograms were analyzed by the method of functional tomography, based on the Fourier transform and on the solution of inverse problem for all frequencies. In this method, one spatial position is assigned to each frequency component. Magnetic resonance images of the head were evaluated to annotate the space to be included in the analysis. The included space was divided into two parts: «brain¼ and «non-brain¼. The frequency components were classified by the feature of their inclusion in one or the other part. The set of frequencies, designated as «brain¼, represented the partial spectrum of the brain signal, while the set of frequencies designated as «non-brain¼, represented the partial spectrum of the physiological noise produced by the head. Both partial spectra shared the same frequency band. From the partial spectra, a time series of the «brain¼ area signal and «non-brain¼ area head noise were reconstructed. Summary spectral power of the signal was found to be ten times greater than the noise. The proposed method makes it possible to analyze in detail both the signal and the noise components of the encephalogram and to filter the magnetic encephalogram.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Encéfalo/fisiología , Análisis de Fourier , Cabeza , Humanos , Imagen por Resonancia Magnética/métodos
6.
Phys Rev Lett ; 129(3): 030601, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35905347

RESUMEN

We investigate, theoretically and experimentally, the thermodynamic performance of a minimal three-qubit heat-bath algorithmic cooling refrigerator. We analytically compute the coefficient of performance, the cooling power, and the polarization of the target qubit for an arbitrary number of cycles, taking realistic experimental imperfections into account. We determine their fundamental upper bounds in the ideal reversible limit and show that these values may be experimentally approached using a system of three qubits in a nitrogen-vacancy center in diamond.

7.
Front Immunol ; 13: 824263, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35774779

RESUMEN

Members of the innate immune system, innate lymphoid cells (ILCs), encompass five major populations (Natural Killer (NK) cells, ILC1s, ILC2s, ILC3s, and lymphoid tissue inducer cells) whose functions include defense against pathogens, surveillance of tumorigenesis, and regulation of tissue homeostasis and remodeling. ILCs are present in the uterine environment of humans and mice and are dynamically regulated during the reproductive cycle and pregnancy. These cells have been repurposed to support pregnancy promoting maternal immune tolerance and placental development. To accomplish their tasks, immune cells employ several cellular and molecular mechanisms. They have the capacity to remember a previously encountered antigen and mount a more effective response to succeeding events. Memory responses are not an exclusive feature of the adaptive immune system, but also occur in innate immune cells. Innate immune memory has already been demonstrated in monocytes/macrophages, neutrophils, dendritic cells, and ILCs. A population of decidual NK cells characterized by elevated expression of NKG2C and LILRB1 as well as a distinctive transcriptional and epigenetic profile was found to expand during subsequent pregnancies in humans. These cells secrete high amounts of interferon-γ and vascular endothelial growth factor likely favoring placentation. Similarly, uterine ILC1s in mice upregulate CXCR6 and expand in second pregnancies. These data provide evidence on the development of immunological memory of pregnancy. In this article, the characteristics, functions, and localization of ILCs are reviewed, emphasizing available data on the uterine environment. Following, the concept of innate immune memory and its mechanisms, which include epigenetic changes and metabolic rewiring, are presented. Finally, the emerging role of innate immune memory on reproduction is discussed. Advances in the comprehension of ILC functions and innate immune memory may contribute to uncovering the immunological mechanisms underlying female fertility/infertility, placental development, and distinct outcomes in second pregnancies related to higher birth weight and lower incidence of complications.


Asunto(s)
Inmunidad Innata , Factor A de Crecimiento Endotelial Vascular , Animales , Femenino , Inmunidad Innata/fisiología , Células Asesinas Naturales , Ratones , Placenta , Embarazo , Reproducción
8.
J Food Sci Technol ; 59(6): 2510-2515, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35602426

RESUMEN

The indiscriminate utilization of agrochemicals causes environmental and animal life impacts. In this regard, methodologies have been developed to offer efficiency and quickness for agrochemicals detection. Due to their selectivity and molecular recognition sites, Molecular Imprinted Polymer (MIPs) have been widely employed in some areas, including biotechnology, waste analyses, foodstuff, biological fluids, and others. This work proposed developing a method to determine aminocarb, pirimicarb, dimethoate, omethoate, pyridaphenthion, and fenitrothion pesticides using molecularly imprinted polymer combined with solid-phase extraction (MIP-SPE) for clean-up and paper spray ionization mass spectrometry for their analysis. Extractions analysis for Aminocarb, Pirimicarb, and Omethoate using MIP-SPE showed better performance when compared with MIP and NIP. The R 2 values were found with R 2 > 0.98 for all pesticides, and LODs and LOQs values were 50 and 100 µg kg-1, respectively. The precision and accuracy were assessed at three concentration levels-low, medium, and high. The precision values (interday and intraday) were below 10%, and the variation of recovery was between 80 and 120% for all pesticides. Therefore, it was possible to verify the presence of two carbamates and five organophosphorus without the necessity of preconcentration samples with precision and good recovery. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05464-7.

9.
Int J Toxicol ; 41(3): 234-242, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35437033

RESUMEN

The 5-year relative survival rate estimate of treated patients with non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) is ∼50% since they generally present with tumor progression, relapse, metastasis, and/or chemoresistance. The expression of cytochrome P450 (CYP) enzymes in malignancies can affect the pharmacology of drugs commonly used in chemotherapy or confer susceptibility to development of chemical carcinogenesis; in addition, their specific tumor expression can be used as a therapeutic target. Using qPCR and Western blot assays, the expression of CYP1B1, CYP2E1, CYP3A4, and CYP3A5 were analyzed in a cohort of tumor tissue paired with non-malignant adjacent tissue of patients with NRSTS. The mRNA and protein expression of CYP1B1, CYP2E1, and CYP3A4 were significantly increased in tumor tissue. We propose that the expression of these isoforms is related to carcinogenesis and chemoresistance frequently observed in these neoplasms.


Asunto(s)
Citocromo P-450 CYP3A , Sarcoma , Carcinogénesis , Niño , Citocromo P-450 CYP2E1/metabolismo , Citocromo P-450 CYP3A/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Humanos , Sarcoma/tratamiento farmacológico , Sarcoma/genética , Sarcoma/patología
10.
Front Aging Neurosci ; 14: 813531, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35273490

RESUMEN

The neurophysiological footprint of brain activity after cardiac arrest and during near-death experience (NDE) is not well understood. Although a hypoactive state of brain activity has been assumed, experimental animal studies have shown increased activity after cardiac arrest, particularly in the gamma-band, resulting from hypercapnia prior to and cessation of cerebral blood flow after cardiac arrest. No study has yet investigated this matter in humans. Here, we present continuous electroencephalography (EEG) recording from a dying human brain, obtained from an 87-year-old patient undergoing cardiac arrest after traumatic subdural hematoma. An increase of absolute power in gamma activity in the narrow and broad bands and a decrease in theta power is seen after suppression of bilateral hemispheric responses. After cardiac arrest, delta, beta, alpha and gamma power were decreased but a higher percentage of relative gamma power was observed when compared to the interictal interval. Cross-frequency coupling revealed modulation of left-hemispheric gamma activity by alpha and theta rhythms across all windows, even after cessation of cerebral blood flow. The strongest coupling is observed for narrow- and broad-band gamma activity by the alpha waves during left-sided suppression and after cardiac arrest. Albeit the influence of neuronal injury and swelling, our data provide the first evidence from the dying human brain in a non-experimental, real-life acute care clinical setting and advocate that the human brain may possess the capability to generate coordinated activity during the near-death period.

11.
Mol Aspects Med ; 87: 101023, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34521556

RESUMEN

Tobacco smoking is an important public health issue recognized by the world health organization as one of the most serious, preventable risk factors for developing a series of pregnancy pathologies. Maternal smoking is positively associated with intrauterine growth restriction (IUGR) and gestational diabetes (GDM), but negatively associated with preeclampsia (PE). In this review, we examine epidemiological, clinical and laboratory studies of smoking effects on immunoregulation during pregnancy, trophoblast function, and placental vasculature development and metabolism. We aim to identify effects of tobacco smoke components on specific placental compartments or cells, which may contribute to the understanding of the influences of maternal smoking on placenta function in normal and pathological pregnancies. Data corroborates that in any trimester, smoking is unsafe for pregnancy and that its detrimental effects outweigh questionable benefits. The effects of maternal smoking on the maternal immune regulation throughout pregnancy and the impact of different tobacco products on fetal growth have not yet been fully understood. Smoking cessation rather than treatment with replacement therapies is recommended for future mothers because also single components of tobacco and its smoke may have detrimental effects on placental function.


Asunto(s)
Placenta , Fumar , Femenino , Retardo del Crecimiento Fetal/epidemiología , Retardo del Crecimiento Fetal/etiología , Retardo del Crecimiento Fetal/metabolismo , Humanos , Placenta/metabolismo , Embarazo , Fumar/efectos adversos , Fumar/metabolismo , Fumar Tabaco , Uso de Tabaco , Trofoblastos/metabolismo
12.
Sci Rep ; 11(1): 15703, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34344908

RESUMEN

After 43 years of repose, Taal Volcano erupted on 12 January 2020 forming hazardous base surges. Using field, remote sensing (i.e. UAV and LiDAR), and numerical methods, we gathered primary data to generate well-constrained observed information on dune bedform characteristics, impact dynamic pressures and velocities of base surges. This is to advance our knowledge on this type of hazard to understand and evaluate its consequences and risks. The dilute and wet surges traveled at 50-60 ms-1 near the crater rim and decelerated before making impact on coastal communities with dynamic pressures of at least 1.7 kPa. The base surges killed more than a thousand livestock in the southeast of Taal Volcano Island, and then traveled another ~ 600 m offshore. This work is a rare document of a complete, fresh, and practically undisturbed base surge deposit, important in the study of dune deposits formed by volcanic and other processes on Earth and other planets.

13.
Nature ; 596(7870): 58-62, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34349289

RESUMEN

Macroscale analogues1-3 of microscopic spin systems offer direct insights into fundamental physical principles, thereby advancing our understanding of synchronization phenomena4 and informing the design of novel classes of chiral metamaterials5-7. Here we introduce hydrodynamic spin lattices (HSLs) of 'walking' droplets as a class of active spin systems with particle-wave coupling. HSLs reveal various non-equilibrium symmetry-breaking phenomena, including transitions from antiferromagnetic to ferromagnetic order that can be controlled by varying the lattice geometry and system rotation8. Theoretical predictions based on a generalized Kuramoto model4 derived from first principles rationalize our experimental observations, establishing HSLs as a versatile platform for exploring active phase oscillator dynamics. The tunability of HSLs suggests exciting directions for future research, from active spin-wave dynamics to hydrodynamic analogue computation and droplet-based topological insulators.

14.
Phys Rev E ; 103(6-1): 062215, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34271671

RESUMEN

A discrete and periodic complex Ginzburg-Landau equation, coupled to a mean equation, is systematically derived from a driven and dissipative lattice oscillator model, close to the onset of a supercritical Andronov-Hopf bifurcation. The oscillator model is inspired by recent experiments exploring active vibrations of quasi-one-dimensional lattices of self-propelled millimetric droplets bouncing on a vertically vibrating fluid bath. Our systematic derivation provides a direct link between the constitutive properties of the lattice system and the coefficients of the resultant amplitude equations, paving the way to compare the emergent nonlinear dynamics-namely, the onset and formation of discrete dark solitons, breathers, and traveling waves-against experiments. The framework presented herein is expected to be applicable to a wider class of oscillators characterized by the presence of a dynamic coupling potential between particles. More broadly, our results point to deeper connections between nonlinear oscillators and the physics of active and driven matter.

15.
PLoS One ; 16(6): e0253894, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34185801

RESUMEN

OBJECTIVE: To describe the laboratory parameters and biomarkers of the cytokine storm syndrome associated with severe and fatal COVID-19 cases. METHODS: A search with standardized descriptors and synonyms was performed on November 28th, 2020 of the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, LILACS, and IBECS to identify studies of interest. Grey literature searches and snowballing techniques were additionally utilized to identify yet-unpublished works and related citations. Two review authors independently screened the retrieved titles and abstracts, selected eligible studies for inclusion, extracted data from the included studies, and then assessed the risk of bias using the Newcastle-Ottawa Scale. Eligible studies were those including laboratory parameters-including serum interleukin-6 levels-from mild, moderate, or severe COVID-19 cases. Laboratory parameters, such as interleukin-6, ferritin, hematology, C-Reactive Protein, procalcitonin, lactate dehydrogenase, aspartate aminotransferase, creatinine, and D-dimer, were extracted from the studies. Meta-analyses were conducted using the laboratory data to estimate mean differences with associated 95% confidence intervals. DATA SYNTHESIS: The database search yielded 9,620 records; 40 studies (containing a total of 9,542 patients) were included in the final analysis. Twenty-one studies (n = 4,313) assessed laboratory data related to severe COVID-19 cases, eighteen studies (n = 4,681) assessed predictors for fatal COVID-19 cases and one study (n = 548) assessed laboratory biomarkers related to severe and fatal COVID-19 cases. Lymphopenia, thrombocytopenia, and elevated levels of interleukin-6, ferritin, D-dimer, aspartate aminotransferase, C-Reactive-Protein, procalcitonin, creatinine, neutrophils and leucocytes were associated with severe and fatal COVID-19 cases. CONCLUSIONS: This review points to interleukin-6, ferritin, leukocytes, neutrophils, lymphocytes, platelets, C-Reactive Protein, procalcitonin, lactate dehydrogenase, aspartate aminotransferase, creatinine, and D-dimer as important biomarkers of cytokine storm syndrome. Elevated levels of interleukin-6 and hyperferritinemia should be considered as red flags of systemic inflammation and poor prognosis in COVID-19.


Asunto(s)
Biomarcadores/sangre , COVID-19/patología , Síndrome de Liberación de Citoquinas/diagnóstico , Proteína C-Reactiva/análisis , COVID-19/complicaciones , COVID-19/mortalidad , COVID-19/virología , Síndrome de Liberación de Citoquinas/etiología , Ferritinas/sangre , Humanos , Interleucina-6/sangre , Leucocitos/citología , Leucocitos/metabolismo , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad
16.
Plant Signal Behav ; 16(10): 1927562, 2021 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-34120565

RESUMEN

Most textbook definitions recognize only animals as having nervous systems. However, for the past couple decades, botanists have been meticulously studying long-distance signaling systems in plants, and some researchers have stated that plants have a simple nervous system. Thus, an academic conflict has emerged between those who defend and those who deny the existence of a nervous system in plants. This article analyses that debate, and we propose an alternative to answering yes or no: broadening the definition of a nervous system to include plants. We claim that a definition broader than the current one, which is based only on a phylogenetic viewpoint, would be helpful in obtaining a deeper understanding of how evolution has driven the features of signal generation, transmission and processing in multicellular beings. Also, we propose two possible definitions and exemplify how broader a definition allows for new viewpoints on the evolution of plants, animals and the nervous system.


Asunto(s)
Evolución Biológica , Fenómenos Fisiológicos del Sistema Nervioso , Fenómenos Fisiológicos de las Plantas , Animales , Fenómenos Electrofisiológicos , Transducción de Señal , Terminología como Asunto
17.
Arch Gynecol Obstet ; 303(6): 1513-1522, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33575847

RESUMEN

PURPOSE: Several roles are attributed to the myometrium including sperm and embryo transport, menstrual discharge, control of uterine blood flow, and labor. Although being a target of diabetes complications, the influence of high glucose on this compartment has been poorly investigated. Both miRNAs and IGF1R are associated with diabetic complications in different tissues. Herein, we examined the effects of high glucose on the expression of miRNAs and IGF1R signaling pathway in the human myometrium. METHODS: Human myometrial explants were cultivated for 48 h under either high or low glucose conditions. Thereafter, the conditioned medium was collected for biochemical analyses and the myometrial samples were processed for histological examination as well as miRNA and mRNA expression profiling by qPCR. RESULTS: Myometrial structure and morphology were well preserved after 48 h of cultivation in both high and low glucose conditions. Levels of lactate, creatinine, LDH and estrogen in the supernatant were similar between groups. An explorative screening by qPCR arrays revealed that 6 out of 754 investigated miRNAs were differentially expressed in the high glucose group. Data validation by single qPCR assays confirmed diminished expression of miR-215-5p and miR-296-5p, and also revealed reduced miR-497-3p levels. Accordingly, mRNA levels of IGF1R and its downstream mediators FOXO3 and PDCD4, which are potentially targeted by miR-497-3p, were elevated under high glucose conditions. In contrast, mRNA expression of IGF1, PTEN, and GLUT1 was unchanged. CONCLUSIONS: The human myometrium responds to short-term exposure (48 h) to high glucose concentrations by regulating the expression of miRNAs, IGF1R and its downstream targets.


Asunto(s)
Trabajo de Parto , Transducción de Señal , Adulto , Proteínas Reguladoras de la Apoptosis , Femenino , Glucosa , Humanos , MicroARNs/genética , Persona de Mediana Edad , Miometrio , Embarazo , Proteínas de Unión al ARN , Receptor IGF Tipo 1
18.
Placenta ; 104: 199-207, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33418345

RESUMEN

Increasing human exposure to nanoparticles (NPs) from various sources raises concerns for public health, especially for vulnerable risk groups like pregnant women and their developing fetuses. However, nanomedicine and the prospect of creating safe and effective NP-based formulations of drugs hold great promise to revolutionize treatment during pregnancy. With maternal and fetal health at stake, risks and opportunities of NPs in pregnancy need to be carefully investigated. Importantly, a comprehensive understanding of NP transport and effects at the placenta is urgently needed considering the central position of the placenta at the maternal-fetal interface and its many essential functions to enable successful pregnancy. The perfusion of human placental tissue provides a great opportunity to achieve predictive human relevant insights, circumventing uncertainties due to considerable differences in placental structure and function across species. Here, we have reviewed the current literature on the ex vivo human placenta perfusion of NPs. From 16 available studies, it was evident that placental uptake and transfer of NPs are highly dependent on their characteristics like size and surface modifications, which is in line with previous observations from in vitro and animal transport studies. These studies further revealed that special considerations apply for the perfusion of NPs and we identified relevant controls that should be implemented in future perfusion studies. While current studies mostly focused on placental transfer of NPs to conclude on potential fetal exposure, the ex vivo placental perfusion model has considerable potential to reveal novel insights on NP effects on placental tissue functionality and signaling that could indirectly affect maternal-fetal health.


Asunto(s)
Nanopartículas/análisis , Placenta/química , Animales , Transporte Biológico , Femenino , Humanos , Intercambio Materno-Fetal , Nanomedicina , Embarazo
19.
Am J Reprod Immunol ; 85(2): e13383, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33251688

RESUMEN

Extracellular vesicle (EV)-mediated communication has been implicated in the cooperative alliance between trophoblast and immune cells toward maternal tolerance and placentation. Syncytiotrophoblast cells secrete EVs directly into the maternal circulation, which are taken up by immune cells, endothelial cells, and other cell types. Initial evidence also shows that EVs produced by immune cells are, in turn, incorporated by trophoblast cells and modulate placental responses. Non-coding RNAs (ncRNAs), proteins, and lipid mediators transported in EVs are able to influence proliferation, differentiation, cytokine production, and immunological responses of recipient cells. The molecular alphabet and cellular targets involved in this dialogue are being revealed. Nevertheless, several questions regarding the whole content, surface markers, and biological functions of EVs still remain to be investigated in both physiological and pathological conditions. Analysis of circulating EVs in maternal blood has the potential to serve as a minimally invasive approach to monitoring placental functions and immunological features of pregnancy, aiding in the diagnostics of complications. This review addresses the immunomodulatory properties of EVs and their tasks in the communication between placental and immune cells.


Asunto(s)
Vesículas Extracelulares/inmunología , Placenta/inmunología , Embarazo/inmunología , Trofoblastos/inmunología , Animales , Biomarcadores , Comunicación Celular , Femenino , Humanos , Tolerancia Inmunológica , Inmunidad Celular , Inmunomodulación , Placentación
20.
Am J Reprod Immunol ; 86(2): e13377, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33175429

RESUMEN

PROBLEM: Extracellular vesicles (EVs) released by the placenta are packed with biological information and play a major role in fetomaternal communication. Here, we describe a comprehensive set-up for the enrichment and characterization of EVs from human placenta perfusion and their application in further assays. METHOD OF STUDY: Human term placentas were used for 3 h ex vivo one-sided perfusions to simulate the intervillous circulation. Thereafter, populations of small (sEVs) and large EV (lEVs) were enriched from placental perfusate via serial ultracentrifugation. Following, EV populations were characterized regarding their size, protein concentration, RNA levels, expression of surface markers as well as their uptake and miRNA transfer to recipient cells. RESULTS: The sEV and lEV fractions from an entire perfusate yielded, respectively, 294 ± 32 µg and 525 ± 96 µg of protein equivalents and 2.6 ± 0.5 µg and 3.6 ± 0.9 µg of RNA. The sEV fraction had a mean diameter of 117 ± 47 nm, and the lEV fraction presented 236 ± 54 nm. CD63 was strongly detected by dot blot in sEVs, whereas only traces of this marker were found in lEVs. Both EV fractions were positive for the trophoblast marker PLAP (placental alkaline phosphatase) and annexin A1. EV internalization in immune cells was visualized by confocal microscopy, and the transfer of placental miRNAs was detected by quantitative real-time PCR (qPCR). CONCLUSIONS: Enriched EV populations showed characteristic features of sEVs and lEVs. EV uptake and transfer of miRNAs to recipient cells demonstrated their functional integrity. Therefore, we advocate the ex vivo one-sided placenta perfusion as a robust approach for the collection of placental EVs.


Asunto(s)
Vesículas Extracelulares/metabolismo , Placenta/metabolismo , Femenino , Humanos , Perfusión , Embarazo , Proteómica
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA