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1.
Environ Res ; 252(Pt 1): 118878, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582417

RESUMO

Fibrous erionite is the only zeolite classified as Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Carcinogenesis induced by erionite is thought to involve several factors as biopersistence, the iron role and cation exchange processes. To better understand these mechanisms, a detailed investigation at the micro scale was performed, collecting elemental information on iron and cation release and their distribution in biological systems by synchrotron micro-X-ray fluorescence mapping (SR-micro-XRF) and synchrotron micro-X-ray absorption spectroscopy (SR-micro-XANES) at the TwinMic beamline (Elettra synchrotron) and at the ID21 beamline of the European Synchrotron Radiation Facility (ESRF). By microscopy and chemical mapping, highly detailed maps of the chemical and morphological interaction of biological systems with fibres could be produced. In detail, THP-1 cell line derived macrophages, used as in vitro model, were analysed during erionite-Na phagocytosis at different time intervals, after single dose exposure. For comparison, cellular fluorescent probes were also used to evaluate the intracellular free sodium and calcium concentrations. Synchrotron analyses visualised the spatial distribution of both fibre and mineral particle associated metals during the phagocytosis, describing the mechanism of internalisation of erionite-Na and its accessory mineral phases. The intracellular distribution of metals and other cations was mapped to evaluate metal release, speciation changes and/or cation exchange during phagocytosis. The fluorescent probes complemented microchemical data clarifying, and confirming, the cation distribution observed in the SR-micro-XRF maps. The significant cytoplasmic calcium decrease, and the concomitant sodium increase, after the fibre phagocytosis seemed due to activation of plasma membrane cations exchangers triggered by the internalisation while, surprisingly, the ion-exchange capacity of erionite-Na could play a minor role in the disruption of the two cations intracellular homeostasis. These results help to elucidate the role of cations in the toxicity of erionite-treated THP-1 macrophages and add knowledge to its carcinogenicity process.


Assuntos
Macrófagos , Síncrotrons , Zeolitas , Humanos , Zeolitas/toxicidade , Zeolitas/química , Macrófagos/efeitos dos fármacos , Células THP-1 , Cátions , Espectrometria por Raios X , Fagocitose/efeitos dos fármacos , Cálcio/metabolismo , Sódio
2.
Analyst ; 149(3): 700-706, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38054815

RESUMO

Multimodal imaging and spectroscopy like concurrent scanning transmission X-ray microscopy (STXM) and X-ray fluorescence (XRF) are highly desirable as they allow retrieving complementary information. This paper reports on the design, development, integration and field testing of a novel in situ atomic force microscopy (AFM) instrument for operation under high vacuum in a synchrotron soft X-ray microscopy STXM-XRF end-station. A combination of µXRF and AFM is demonstrated for the first time in the soft X-ray regime, with an outlook for the full XRF-STXM-AFM combination.

3.
PLoS One ; 18(11): e0285057, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37943764

RESUMO

Scanning microscopies and spectroscopies like X-ray Fluorescence (XRF), Scanning Transmission X-ray Microscopy (STXM), and Ptychography are of very high scientific importance as they can be employed in several research fields. Methodology and technology advances aim at analysing larger samples at better resolutions, improved sensitivities and higher acquisition speeds. The frontiers of those advances are in detectors, radiation sources, motors, but also in acquisition and analysis software together with general methodology improvements. We have recently introduced and fully implemented an intelligent scanning methodology based on compressive sensing, on a soft X-ray microscopy beamline. This demonstrated sparse low energy XRF scanning of dynamically chosen regions of interest in combination with STXM, yielding spectroimaging data in the megapixel-range and in shorter timeframes than were previously not feasible. This research has been further developed and has been applied to scientific applications in biology. The developments are mostly in the dynamic triggering decisional mechanism in order to incorporate modern Machine Learning (ML) but also in the suitable integration of the method in the control system, making it available for other beamlines and imaging techniques. On the applications front, the method was previously successfully used on different samples, from lung and ovarian human tissues to plant root sections. This manuscript introduces the latest methodology advances and demonstrates their applications in life and environmental sciences. Lastly, it highlights the auxiliary development of a mobile application, designed to assist the user in the selection of specific regions of interest in an easy way.


Assuntos
Compressão de Dados , Microscopia , Humanos , Síncrotrons , Análise Espectral , Fenômenos Físicos
4.
Front Immunol ; 14: 1247747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744340

RESUMO

The release of nanoplastics (NPs) in the environment is a significant health concern for long-term exposed humans. Although their usage has certainly revolutionized several application fields, at nanometer size, NPs can easily interact at the cellular level, resulting in potential harmful effects. Micro/Nanoplastics (M/NPs) have a demonstrated impact on mammalian endocrine components, such as the thyroid, adrenal gland, testes, and ovaries, while more investigations on prenatal and postnatal exposure are urgently required. The number of literature studies on the NPs' presence in biological samples is increasing. However, only a few offer a close study on the model environmental NP-immune system interaction exploited by advanced microscopy techniques. The present study highlights substantial morphological and lipid metabolism alterations in human M1 macrophages exposed to labeled polypropylene and polyvinyl chloride nanoparticles (PP and PVC NPs) (20 µg/ml). The results are interpreted by advanced microscopy techniques combined with standard laboratory tests and fluorescence microscopy. We report the accurate detection of polymeric nanoparticles doped with cadmium selenide quantum dots (CdSe-QDs NPs) by following the Se (L line) X-ray fluorescence emission peak at higher sub-cellular resolution, compared to the supportive light fluorescence microscopy. In addition, scanning transmission X-ray microscopy (STXM) imaging successfully revealed morphological changes in NP-exposed macrophages, providing input for Fourier transform infrared (FTIR) spectroscopy analyses, which underlined the chemical modifications in macromolecular components, specifically in lipid response. The present evidence was confirmed by quantifying the lipid droplet (LD) contents in PP and PVC NPs-exposed macrophages (0-100 µg/ml) by Oil Red O staining. Hence, even at experimental NPs' concentrations and incubation time, they do not significantly affect cell viability; they cause an evident lipid metabolism impairment, a hallmark of phagocytosis and oxidative stress.


Assuntos
Metabolismo dos Lipídeos , Microplásticos , Humanos , Animais , Feminino , Gravidez , Síncrotrons , Macrófagos , Microscopia de Fluorescência , Mamíferos
5.
Molecules ; 28(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36838979

RESUMO

BACKGROUND: Although X-ray fluorescence microscopy is becoming a widely used technique for single-cell analysis, sample preparation for this microscopy remains one of the main challenges in obtaining optimal conditions for the measurements in the X-ray regime. The information available to researchers on sample treatment is inadequate and unclear, sometimes leading to wasted time and jeopardizing the experiment's success. Many cell fixation methods have been described, but none of them have been systematically tested and declared the most suitable for synchrotron X-ray microscopy. METHODS: The HEC-1-A endometrial cells, human spermatozoa, and human embryonic kidney (HEK-293) cells were fixed with organic solvents and cross-linking methods: 70% ethanol, 3.7%, and 2% paraformaldehyde; in addition, HEK-293 cells were subjected to methanol/ C3H6O treatment and cryofixation. Fixation methods were compared by coupling low-energy X-ray fluorescence with scanning transmission X-ray microscopy and atomic force microscopy. RESULTS: Organic solvents lead to greater dehydration of cells, which has the most significant effect on the distribution and depletion of diffusion elements. Paraformaldehyde provides robust and reproducible data. Finally, the cryofixed cells provide the best morphology and element content results. CONCLUSION: Although cryofixation seems to be the most appropriate method as it allows for keeping cells closer to physiological conditions, it has some technical limitations. Paraformaldehyde, when used at the average concentration of 3.7%, is also an excellent alternative for X-ray microscopy.


Assuntos
Raios X , Humanos , Células HEK293 , Radiografia , Microscopia de Força Atômica
6.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36834632

RESUMO

Scanning transmission X-ray microscopy (STXM) provides the imaging of biological specimens allowing the parallel collection of localized spectroscopic information by X-ray fluorescence (XRF) and/or X-ray Absorption Near Edge Spectroscopy (XANES). The complex metabolic mechanisms which can take place in biological systems can be explored by these techniques by tracing even small quantities of the chemical elements involved in the metabolic pathways. Here, we present a review of the most recent publications in the synchrotrons' scenario where soft X-ray spectro-microscopy has been employed in life science as well as in environmental research.


Assuntos
Microscopia , Síncrotrons , Microscopia/métodos , Raios X , Radiografia , Espectroscopia por Absorção de Raios X
7.
Hum Reprod Open ; 2023(1): hoac056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36579123

RESUMO

STUDY QUESTION: Do small and asymptomatic intramural and subserosal uterine fibroids affect female fertility? SUMMARY ANSWER: Small and asymptomatic fibroids that do not encroach the endometrial cavity appear to not markedly affect female fertility. WHAT IS KNOWN ALREADY: The available evidence on uterine fibroids and fertility is limited. Most information has been obtained in IVF settings by comparing the success in women affected and not affected by fibroids. These studies have shown a detrimental effect of submucosal and possibly intramural fibroids. However, this study design provides information only on embryo implantation, not on female fertility in general. STUDY DESIGN SIZE DURATION: A retrospective observational case-control study on 200 women whose partner was diagnosed with severe male infertility and 200 women with unexplained infertility was conducted. If the null hypothesis (that fibroids do not affect fertility) is valid, one would expect a similar prevalence of fibroids in the two study groups. Conversely, if fibroids do impact fertility, one would expect a higher prevalence among women with unexplained infertility. The study was carried out at the Infertility Unit of the Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico covering a 5-year period between January 2014 and June 2020. PARTICIPANTS/MATERIALS SETTING METHODS: We retrospectively recruited women seeking pregnancy whose partner was repeatedly documented to have a sperm concentration below 1 million/ml and matched them by age and study period to a group of women with unexplained infertility. The latter group of women was considered as a case group (infertile subjects), while the former group of women was considered as a control group (reflecting the general female population). Women with fibroids could be included in both study groups; only those with submucosal lesions were excluded. MAIN RESULTS AND THE ROLE OF CHANCE: Fibroids were diagnosed in 31 women (16%) with unexplained infertility and in 32 women (16%) with severe male factor infertility. The adjusted odds ratio of carrying fibroids in women with unexplained infertility was 0.91 (95% CI: 0.52-1.58). Subgroup analyses according to number, dimension and location of fibroids failed to highlight an increased risk of infertility in any group. LIMITATIONS REASONS FOR CAUTION: This is a retrospective study and some inaccuracies in fibroids detection cannot be ruled out. Moreover, the relatively small sample size hampers robust subgroup analyses. Even though we excluded women with patent causes of infertility, some women with specific causes of infertility could have been included among controls (yet are expected to account for <10% of the group). WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that small fibroids that do not encroach the endometrial cavity do not markedly affect female fertility. This information is clinically relevant when counseling infertile women with small fibroids and an otherwise unremarkable diagnostic work-up. Surgery may still be considered but only in selected cases. STUDY FUNDING/COMPETING INTERESTS: This study was partially funded by Italian Ministry of Health: current research IRCCS. E.S. reports grants from Ferring, grants and personal fees from Merck, and grants and personal fees from Theramex outside the submitted work. All the other authors do not have any competing interest to declare. TRIAL REGISTRATION NUMBER: N/A.

8.
Sensors (Basel) ; 22(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35746377

RESUMO

In hard X-ray applications that require high detection efficiency and short response times, such as synchrotron radiation-based Mössbauer absorption spectroscopy and time-resolved fluorescence or photon beam position monitoring, III-V-compound semiconductors, and dedicated alloys offer some advantages over the Si-based technologies traditionally used in solid-state photodetectors. Amongst them, gallium arsenide (GaAs) is one of the most valuable materials thanks to its unique characteristics. At the same time, implementing charge-multiplication mechanisms within the sensor may become of critical importance in cases where the photogenerated signal needs an intrinsic amplification before being acquired by the front-end electronics, such as in the case of a very weak photon flux or when single-photon detection is required. Some GaAs-based avalanche photodiodes (APDs) were grown by a molecular beam epitaxy to fulfill these needs; by means of band gap engineering, we realised devices with separate absorption and multiplication region(s) (SAM), the latter featuring a so-called staircase structure to reduce the multiplication noise. This work reports on the experimental characterisations of gain, noise, and charge collection efficiencies of three series of GaAs APDs featuring different thicknesses of the absorption regions. These devices have been developed to investigate the role of such thicknesses and the presence of traps or defects at the metal-semiconductor interfaces responsible for charge loss, in order to lay the groundwork for the future development of very thick GaAs devices (thicker than 100 µm) for hard X-rays. Several measurements were carried out on such devices with both lasers and synchrotron light sources, inducing photon absorption with X-ray microbeams at variable and controlled depths. In this way, we verified both the role of the thickness of the absorption region in the collection efficiency and the possibility of using the APDs without reaching the punch-through voltage, thus preventing the noise induced by charge multiplication in the absorption region. These devices, with thicknesses suitable for soft X-ray detection, have also shown good characteristics in terms of internal amplification and reduction of multiplication noise, in line with numerical simulations.

9.
J Assist Reprod Genet ; 39(4): 883-892, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35445905

RESUMO

PURPOSE: The study aims to summarize current knowledge on the use of oil in embryo culture systems, with a focus on proper management of different types of oil and possible impact on culture systems. METHODS: PubMed was used to search the MEDLINE database for peer-reviewed English-language original articles and reviews concerning the use of oil in embryo culture systems. Searches were performed by adopting "embryo," "culture media," "oil," and "contaminants" as main terms. The most relevant publications were assessed and discussed critically. RESULTS: Oils used in IVF are complex mixtures of straight-chain hydrocarbons, cyclic and aromatic hydrocarbons, and unsaturated hydrocarbons, whose precise composition influences their chemical and physical properties. Possible presence of contaminants suggests their storage at 4 °C in the dark to prevent peroxidation. Washing, generally performed by manufacturers prior to commercialization, may remove trace chemical contaminants. Oils reduce evaporation from culture media at rates depending on their chemical physical properties, culture system parameters, and incubator atmosphere. Contaminants - mainly metal ion and plastic components derived from refinement processes and storage - can pass to the aqueous phase of culture systems and affect embryo development. CONCLUSIONS: Oils are essential components of culture systems. Their original quality and composition, storage, handling, and use can affect embryo development with significant efficiency and safety implications.


Assuntos
Técnicas de Cultura Embrionária , Óleo Mineral , Meios de Cultura/química , Fertilização in vitro , Humanos , Óleos
10.
Environ Sci Technol ; 55(15): 10769-10783, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34308629

RESUMO

A thorough understanding of the implications of chronic low-dose exposure to engineered nanomaterials through the food chain is lacking. The present study aimed to characterize such a response in Cucurbita pepo L. (zucchini) upon exposure to a potential nanoscale fertilizer: copper oxide (CuO) nanoparticles. Zucchini was grown in soil amended with nano-CuO, bulk CuO (100 mg Kg-1), and CuSO4 (320 mg Kg-1) from germination to flowering (60 days). Nano-CuO treatment had no impact on plant morphology or growth nor pollen formation and viability. The uptake of Cu was comparable in the plant tissues under all treatments. RNA-seq analyses on vegetative and reproductive tissues highlighted common and nanoscale-specific components of the response. Mitochondrial and chloroplast functions were uniquely modulated in response to nanomaterial exposure as compared with conventional bulk and salt forms. X-ray absorption spectroscopy showed that the Cu local structure changed upon nano-CuO internalization, suggesting potential nanoparticle biotransformation within the plant tissues. These findings demonstrate the potential positive physiological, cellular, and molecular response related to nano-CuO application as a plant fertilizer, highlighting the differential mechanisms involved in the exposure to Cu in nanoscale, bulk, or salt forms. Nano-CuO uniquely stimulates plant response in a way that can minimize agrochemical inputs to the environment and therefore could be an important strategy in nanoenabled agriculture.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Nanoestruturas , Cobre/toxicidade , Nanopartículas Metálicas/toxicidade , Óxidos , Raízes de Plantas , Solo
11.
Struct Dyn ; 8(3): 034304, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34169118

RESUMO

Here, we report on the conceptual design, the hardware realization, and the first experimental results of a novel and compact x-ray polarimeter capable of a single-pulse linear polarization angle detection in the extreme ultraviolet photon energy range. The polarimeter is tested by performing time resolved pump-probe experiments on a Ni80Fe20 Permalloy film at the M2,3 Ni edge at an externally seeded free-electron laser source. Comparison with similar experiments reported in the literature shows the advantages of our approach also in view of future experiments.

12.
Reprod Biomed Online ; 43(1): 100-110, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33903032

RESUMO

Available evidence from IVF studies supports a detrimental effect of submucosal and intramural fibroids on embryo implantation. It is misleading, however, to infer evidence obtained in IVF settings to natural fertility. Therefore, a systematic review and meta-analysis was conducted on the effect of fibroids on natural fertility. Studies comparing fertile and infertile women, and those investigating whether the presence of fibroids was a risk factor, were reviewed, as well as studies comparing women with and without fibroids. The aim was also to establish whether the frequency of infertility differed between the two groups. Seven out of 11 selected studies did not aim to establish whether fibroids caused infertility but, rather, whether a history of infertility could be a risk factor for fibroids. A meta-analysis of the four remaining studies that concomitantly evaluated the presence of fibroids and infertility studies highlighted a common odds ratio of fibroids in subfertile women of 3.54 (95% CI 1.55 to 8.11). When focusing on the two most informative studies, i.e. the studies comparing time to pregnancy in women with and without fibroids, the common OR was 1.93 (95% CI 0.89 to 4.18). In conclusion, the association between fibroids and infertility has been insufficiently investigated. Epidemiological studies suggest, but do not demonstrate, that fibroids may interfere with natural fertility. Given the high prevalence of these lesions in women seeking pregnancy, further evidence is urgently needed.


Assuntos
Infertilidade Feminina/etiologia , Leiomioma/complicações , Neoplasias Uterinas/complicações , Feminino , Fertilidade , Humanos , Gravidez
13.
ACS Appl Nano Mater ; 4(2): 1057-1066, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33778418

RESUMO

Plasmon resonance modulation with an external magnetic field (magnetoplasmonics) represents a promising route for the improvement of the sensitivity of plasmon-based refractometric sensing. To this purpose, an accurate material choice is needed to realize hybrid nanostructures with an improved magnetoplasmonic response. In this work, we prepared core@shell nanostructures made of an 8 nm Au core surrounded by an ultrathin iron oxide shell (≤1 nm). The presence of the iron oxide shell was found to significantly enhance the magneto-optical response of the noble metal in the localized surface plasmon region, compared with uncoated Au nanoparticles. With the support of an analytical model, we ascribed the origin of the enhancement to the shell-induced increase in the dielectric permittivity around the Au core. The experiment points out the importance of the spectral position of the plasmonic resonance in determining the magnitude of the magnetoplasmonic response. Moreover, the analytical model proposed here represents a powerful predictive tool for the quantification of the magnetoplasmonic effect based on resonance position engineering, which has significant implications for the design of active magnetoplasmonic devices.

14.
Gynecol Endocrinol ; 37(6): 497-505, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33345661

RESUMO

OBJECTIVE: Infertility is an increasingly frequent health condition, which may depend on female or male factors. Oxidative stress (OS), resulting from a disrupted balance between reactive oxygen species (ROS) and protective antioxidants, affects the reproductive lifespan of men and women. In this review, we examine if alpha lipoic acid (ALA), among the oral supplements currently in use, has an evidence-based beneficial role in the context of female and male infertility. METHODS: We performed a search from English literature using PubMed database with the following keywords: 'female infertility', 'male infertility', 'semen', 'sperm', 'sub-fertile man', 'alpha-lipoic acid', ' alpha lipoic acid', 'lipoid acid', 'endometriosis', 'chronic pelvic pain', 'follicular fluid' and 'oocytes'. We included clinical trials, multicentric studies and reviews. The total number of references found after automatically and manually excluding duplicates was 180. After primary and secondary screening, 28 articles were selected. RESULTS: The available literature demonstrates the positive effects of ALA in multiple processes from oocyte maturation (0.87 ± 0.9% of oocyte in MII vs 0.81 ± 3.9%; p < .05) to fertilization, embryo development (57.7% vs 75.7% grade 1 embryo; p < .05) and reproductive outcomes. Its regular administration both in sub-fertile women and men shows to reduce pelvic pain in endometriosis (p < .05), regularize menstrual flow and metabolic disorders (p < .01) and improve sperm quality (p < .001). CONCLUSIONS: ALA represents a promising new molecule in the field of couple infertility. More clinical studies are needed in order to enhance its use in clinical practice.


Assuntos
Infertilidade Feminina/tratamento farmacológico , Infertilidade Masculina/tratamento farmacológico , Ácido Tióctico/uso terapêutico , Adulto , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Masculina/epidemiologia , Masculino , Oogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sêmen/efeitos dos fármacos , Ácido Tióctico/farmacologia , Adulto Jovem
15.
J Immunother Cancer ; 7(1): 290, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699153

RESUMO

BACKGROUND: The peculiar multiple myeloma microenvironment, characterized by up-regulated levels of several inflammatory chemokines, including the CXCR3 receptor ligands CXCL9 and CXCL10, limits NK cell positioning into the bone marrow by interfering with CXCR4 function. It is still unclear if the consequent reduced influx of transferred cells into the tumor represents a potential limiting factor for the success of NK cell-based adoptive therapy. We hypothesize that inhibition of CXCR3 function on NK cells will result in increased tumor clearance, due to higher NK cell bone marrow infiltration. METHODS: Since different activation protocols differently affect expression and function of homing receptors, we analyzed the bone marrow homing properties and anti-tumor efficacy of NK cells stimulated in vitro with two independent protocols. NK cells were purified from wild-type or Cxcr3-/- mice and incubated with IL-15 alone or with a combination of IL-12, IL-15, IL-18 (IL-12/15/18). Alternatively, CXCR3 function was neutralized in vivo using a specific blocking antibody. NK cell functional behavior and tumor growth were analyzed in bone marrow samples by FACS analysis. RESULTS: Both activation protocols promoted degranulation and IFN-γ production by donor NK cells infiltrating the bone marrow of tumor-bearing mice, although IL-15 promoted a faster but more transient acquisition of functional capacities. In addition, IL-15-activated cells accumulated more in the bone marrow in a short time but showed lower persistence in vivo. Targeting of CXCR3 increased the bone marrow homing capacity of IL-15 but not IL12/15/18 activated NK cells. This effect correlated with a superior and durable myeloma clearance capacity of transferred cells in vivo. CONCLUSIONS: Our results demonstrate that in vitro activation affects NK cell anti-myeloma activity in vivo by regulating their BM infiltration. Furthermore, we provided direct evidence that CXCR3 restrains NK cell anti-tumor capacity in vivo according to the activation protocol used, and that the effects of NK cell-based adoptive immunotherapy for multiple myeloma can be improved by increasing their bone marrow homing through CXCR3 inhibition.


Assuntos
Imunoterapia Adotiva , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Receptores CXCR3/antagonistas & inibidores , Animais , Biomarcadores , Linhagem Celular Tumoral , Movimento Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Humanos , Imunofenotipagem , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Receptores CXCR3/genética , Receptores CXCR3/metabolismo
16.
Front Immunol ; 10: 1569, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354722

RESUMO

NK cell maturation is a continuous process, which initiates in the bone marrow and proceeds in peripheral tissues, where NK cells follow distinct differentiation routes. Drastic phenotypic changes are observed during progression from precursors to mature NK cells, including changes of expression and functionalities of several chemoattractant receptors. Upon differentiation, mature NK cells migrate outside the bone marrow; as well, peculiar subsets of NK cells can also home back to or localize in this anatomic compartment to play specific functions. In humans, NK cells with a tissue resident phenotype have been identified in bone marrow, sharing similarities with tissue resident memory CD8+ T cells; while in mouse, long-lived NK cells undergo homeostatic proliferation in this site during viral infections. The mechanisms underlying NK cell subset localization in the bone marrow have only recently started to be investigated, especially in pathological settings such as tumors or infections. In this review, we discuss the phenotype and function of NK cells as well as their requirements for bone marrow maintenance and/or homing.


Assuntos
Células da Medula Óssea/fisiologia , Células Matadoras Naturais/fisiologia , Subpopulações de Linfócitos/fisiologia , Animais , Diferenciação Celular , Movimento Celular , Homeostase , Humanos , Imunidade Celular , Ativação Linfocitária , Especificidade de Órgãos , Fenótipo
17.
Cell Death Dis ; 9(6): 685, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880901

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. In the pathogenesis of AD a pivotal role is played by two neurotoxic proteins that aggregate and accumulate in the central nervous system: amyloid beta and hyper-phosphorylated tau. Accumulation of extracellular amyloid beta plaques and intracellular hyper-phosphorylated tau tangles, and consequent neuronal loss begins 10-15 years before any cognitive impairment. In addition to cognitive and behavioral deficits, sensorial abnormalities have been described in AD patients and in some AD transgenic mouse models. Retina can be considered a simple model of the brain, as some pathological changes and therapeutic strategies from the brain may be observed or applicable to the retina. Here we propose new retinal biomarkers that could anticipate the AD diagnosis and help the beginning and the follow-up of possible future treatments. We analyzed retinal tissue of triple-transgenic AD mouse model (3xTg-AD) for the presence of pathological hallmarks during disease progression. We found the presence of amyloid beta plaques, tau tangles, neurodegeneration, and astrogliosis in the retinal ganglion cell layer of 3xTg-AD mice, already at pre-symptomatic stage. Moreover, retinal microglia in pre-symptomatic mice showed a ramified, anti-inflammatory phenotype which, during disease progression, switches to a pro-inflammatory, less ramified one, becoming neurotoxic. We hypothesize retina as a window through which monitor AD-related neurodegeneration process.


Assuntos
Doença de Alzheimer/patologia , Biomarcadores/metabolismo , Inflamação/patologia , Degeneração Neural/patologia , Agregados Proteicos , Retina/metabolismo , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/metabolismo , Animais , Contagem de Células , Modelos Animais de Doenças , Progressão da Doença , Hipocampo/patologia , Humanos , Inflamação/complicações , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Degeneração Neural/complicações , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Placa Amiloide/patologia , Proteínas tau/metabolismo
19.
Front Immunol ; 7: 402, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27766097

RESUMO

Chemokines are small chemotactic molecules that play key roles in physiological and pathological conditions. Upon signaling via their specific receptors, chemokines regulate tissue mobilization and trafficking of a wide array of immune cells, including natural killer (NK) cells. Current research is focused on analyzing changes in chemokine/chemokine receptor expression during various diseases to interfere with pathological trafficking of cells or to recruit selected cell types to specific tissues. NK cells are a heterogeneous lymphocyte population comprising several subsets endowed with distinct functional properties and mainly representing distinct stages of a linear development process. Because of their different functional potential, the type of subset that accumulates in a tissue drives the final outcome of NK cell-regulated immune response, leading to either protection or pathology. Correspondingly, chemokine receptors, including CXCR4, CXCR3, and CX3CR1, are differentially expressed by NK cell subsets, and their expression levels can be modulated during NK cell activation. At first, this review will summarize the current knowledge on the contribution of chemokines to the localization and generation of NK cell subsets in homeostasis. How an inappropriate chemotactic response can lead to pathology and how chemokine targeting can therapeutically affect tissue recruitment/localization of distinct NK cell subsets will also be discussed.

20.
Phys Rev Lett ; 111(16): 167401, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24182300

RESUMO

We explore the influence of the phase of localized plasmon resonances on the magneto-optical activity of nanoferromagnets. We demonstrate that these systems can be described as two orthogonal damped oscillators coupled by the spin-orbit interaction. We prove that only the spin-orbit induced transverse plasmon plays an active role on the magneto-optical properties by controlling the relative amplitude and phase lag between the two oscillators. Our theoretical predictions are fully confirmed by magneto-optical Kerr effect and optical extinction measurements in nanostructures of different size and shape.

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