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1.
Small ; 18(14): e2103364, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35195345

RESUMO

The sensory nervous and immune systems work in concert to preserve homeostasis. While this endogenous interplay protects from danger, it may drive chronic pathologies. Currently, genetic engineering of neurons remains the primary approach to interfere selectively with this potentially deleterious interplay. However, such manipulations are not feasible in a clinical setting. Here, this work reports a nanotechnology-enabled concept to silence subsets of unmodified nociceptor neurons that exploits their ability to respond to heat via the transient receptor potential vanilloid type 1 (TRPV1) channel. This strategy uses laser stimulation of antibody-coated gold nanoparticles to heat-activate TRPV1, turning this channel into a cell-specific drug-entry port. This delivery method allows transport of a charged cationic derivative of an N-type calcium channel blocker (CNCB-2) into targeted sensory fibers. CNCB-2 delivery blocks neuronal calcium currents and neuropeptides release, resulting in targeted silencing of nociceptors. Finally, this work demonstrates the ability of the approach to probe neuro-immune crosstalk by targeting cytokine-responsive nociceptors and by successfully preventing nociceptor-induced CD8+ T-cells polarization. Overall, this work constitutes the first demonstration of targeted silencing of nociceptor neuron subsets without requiring genetic modification, establishing a strategy for interfering with deleterious neuro-immune interplays.


Assuntos
Nanopartículas Metálicas , Nociceptores , Linfócitos T CD8-Positivos , Gânglios Espinais , Ouro , Neurônios , Nociceptores/fisiologia , Canais de Cátion TRPV
2.
Andrologia ; 54(7): 1618-1630, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35545511

RESUMO

Poor sperm quality in oligoasthenoteratospermia patients negatively affects assisted reproductive technology outcomes. Therefore, the development of sperm media is necessary to improve sperm parameters. This study investigated the effect of GM-CSF via PI3K/AKT pathway on sperm quality in OAT patients. Semen samples were collected from 20 OAT patients, and each sample was divided into two groups: Experiment and Control. In the experimental group, the samples were incubated with medium containing GM-CSF, and control samples were incubated without GM-CSF. Sperm parameters, mitochondrial membrane potential, acrosome reaction and DFI were studied; in addition, gene expression of PI3KR1, PI3KCA, GLUT1, GLUT3 and AKT1 was analysed, evaluation of PAKT/TAKT, and expression of GLUT 1, 3 was examined; subsequent fertilization rate and embryo quality were assessed. Our data showed that GM-CSF supplementation could significantly increase motility, mitochondrial activity, gene expression of PI3KCA, AKT1, the protein level of PAKT/TAKT and expression of GLUT 1, 3 while it decreases DNA fragmentation. The fertilization rate and embryo quality significantly improved in the treatment group. LY294002 had adverse effects on sperm motility and the PAKT/TAKT ratio. GM-CSF can improve in vitro sperm quality and could be a suitable supplement to sperm media for OAT patients.


Assuntos
Astenozoospermia , Fertilização in vitro , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Astenozoospermia/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Masculino , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Sêmen , Motilidade dos Espermatozoides , Espermatozoides
3.
Magn Reson Chem ; 58(5): 411-426, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32239577

RESUMO

NMR applied to living organisms is arguably the ultimate tool for understanding environmental stress responses and can provide desperately needed information on toxic mechanisms, synergistic effects, sublethal impacts, recovery, and biotransformation of xenobiotics. To perform in vivo NMR spectroscopy, a flow cell system is required to deliver oxygen and food to the organisms while maintaining optimal line shape for NMR spectroscopy. In this tutorial, two such flow cell systems and their constructions are discussed: (a) a single pump high-volume flow cell design is simple to build and ideal for organisms that do not require feeding (i.e., eggs) and (b) a more advanced low-volume double pump flow cell design that permits feeding, maintains optimal water height for water suppression, improves locking and shimming, and uses only a small recirculating volume, thus reducing the amount of xenobiotic required for testing. In addition, key experimental aspects including isotopic enrichment, water suppression, and 2D experiments for both 13 C enriched and natural abundance organisms are discussed.


Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/instrumentação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Espectroscopia de Prótons por Ressonância Magnética/instrumentação , Espectroscopia de Prótons por Ressonância Magnética/métodos , Animais , Chlamydomonas reinhardtii/química , Daphnia/química
4.
Int J Hyperthermia ; 32(6): 657-65, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27380542

RESUMO

PURPOSE: The blood-retina barrier (BRB) is a biological barrier consisting of tightly interconnected endothelial cells inside the retinal vascular network that protects the neural tissue from harmful pathogens and neurotoxic molecules circulating in the bloodstream. Unfortunately, with regard to retinoblastoma, this barrier also prevents systemically administered therapeutics reaching the retinal tissue. In this study we introduce a novel technique to locally and transiently increase BRB permeability for drug delivery using hyperthermia of magnetic nanoparticles (MNPs). MATERIALS AND METHODS: An alternating current (AC) magnetic field was used to induce hyperthermia of locally injected MNPs in the left ophthalmic artery of a rat model. To improve adherence on the surface of the endothelium, commercially available MNPs coated with human transferrin glycoproteins were used. After hyperthermia we assessed the extravasation of systemically injected sodium fluorescein (NaF) as well as Evans blue dye (EBD) into the retinal tissue. RESULTS: Spectrofluorometry and fluorescent microscopy image analysis show a significant increase of dye penetration in the retina where hyperthermia of MNPs was applied. CONCLUSIONS: Our proposed new technique can allow both small and large dye molecules to cross the BRB. While the results are preliminary and thorough evaluation of the retinal tissue following hyperthermia is necessary, this technique has the potential to be an effective mean for the treatment of various diseases such as retinoblastoma.


Assuntos
Barreira Hematorretiniana/metabolismo , Corantes/administração & dosagem , Azul Evans/administração & dosagem , Fluoresceína/administração & dosagem , Hipertermia Induzida , Nanopartículas de Magnetita/administração & dosagem , Animais , Campos Magnéticos , Masculino , Ratos
5.
Biopreserv Biobank ; 22(1): 38-45, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37801668

RESUMO

The cryopreservation-thawing process of spermatozoa cells has negative impacts on their structure, function, and fertility parameters, which are known as cryoinjury. Asthenozoospermia patients are more susceptible to cryoinjury. Granulocyte-macrophage colony-stimulating factor (GM-CSF) increases sperm glucose uptake via the induction of glucose transporters, resulting in increased sperm motility. This study aimed to investigate the efficiency of GM-CSF supplementation of the cryopreservation media for semen samples of asthenoteratozoospermia patients. The study was carried out on 20 semen samples from infertile men referred to diagnosing semen analysis. To avoid subjective bias, two main sperm motility parameters, including velocity along the curvilinear path and velocity along the straight-line path were considered by the computer-assisted sperm analysis system. Afterward, each semen sample was divided into three equal aliquots and randomly assigned to one of the following groups: group I (control, freezing media only), group II (+GM-CSF, freezing medium supplemented with 2 µL/mL GM-CSF), or group III (GM-CSF added after thawing and washing). Following semen thawing, standard parameters, mitochondrial membrane potential (MMP), and the DNA Fragmentation Index were analyzed. Total sperm motility (progressive and non-progressive) improved significantly in group III samples after a 30-minute incubation with GM-CSF compared with the control group (26.5% ± 3.1% vs. 17.51% ± 2.59%). However, no differences in progressive motility or sperm morphology were found among the three thawed samples. The percentage of vitality was significantly higher in group III compared with the other two groups (28.38% ± 3.4% vs. 22.4% ± 3.08% and 22.14% ± 2.77%, respectively) (p < 0.05). JC-1 levels (a marker of MMP) were not significantly different between the examined groups (44.95% ± 8.26% vs. 36.61% ± 6.95% vs. 46.67% ± 7.7%, for control, group II, and group III, respectively) (p > 0.05). GM-CSF may be advantageous as an additive after freezing, improving total motility and viability after 30 minutes of post-thaw incubation; however, when supplied to the freezing media before cryopreservation, it is unable to protect against cryoinjury.


Assuntos
Astenozoospermia , Preservação do Sêmen , Humanos , Masculino , Congelamento , Motilidade dos Espermatozoides , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Sêmen , Citocinas , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/métodos , Crioprotetores/farmacologia
6.
J Environ Manage ; 127: 135-41, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23685274

RESUMO

Results from experiments using an oath to eliminate hypothetical bias in stated preference valuation are presented. An oath has several potential advantages relative to other methods for reducing hypothetical bias. Our empirical results suggest that with an oath, mean hypothetical payments are not different from mean actual payments and that when controlling for experimental participants' characteristics using regression analyses, the oath eliminated hypothetical bias.


Assuntos
Ética , Incerteza , Humanos , Análise Multivariada , Análise de Regressão , Controles Informais da Sociedade
7.
J Cereb Blood Flow Metab ; 39(2): 260-271, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-28792278

RESUMO

Neurovascular coupling (NVC) underlying the local increase in blood flow during neural activity forms the basis of functional brain imaging and is altered in epilepsy. Because astrocytic calcium (Ca2+) signaling is involved in NVC, this study investigates the role of this pathway in epilepsy. Here, we exploit 4-AP induced epileptic events to show that absolute Ca2+ concentration in cortical astrocyte endfeet in vivo correlates with the diameter of precapillary arterioles during neural activity. We simultaneously monitored free Ca2+ concentration in astrocytic endfeet with the Ca2+-sensitive indicator OGB-1 and diameter of adjacent arterioles in the somatosensory cortex of adult mice by two-photon fluorescence lifetime measurements following 4-AP injection. Our results reveal that, regardless of the mechanism by which astrocytic endfoot Ca2+ was elevated during epileptic events, increases in Ca2+ associated with vasodilation for each individual ictal event in the focus. In the remote area, increases in Ca2+ correlated with vasoconstriction at the onset of seizure and vasodilation during the later part of the seizure. Furthermore, a slow increase in absolute Ca2+ with time following multiple seizures was observed, which in turn, correlated with a trend of arteriolar constriction both at the epileptic focus and remote areas.


Assuntos
4-Aminopiridina/efeitos adversos , Astrócitos , Sinalização do Cálcio/efeitos dos fármacos , Epilepsia , Microscopia Intravital , Microscopia de Fluorescência por Excitação Multifotônica , 4-Aminopiridina/farmacologia , Animais , Arteríolas/metabolismo , Arteríolas/patologia , Astrócitos/metabolismo , Astrócitos/patologia , Cálcio/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Epilepsia/patologia , Masculino , Camundongos
8.
ACS Nano ; 13(1): 408-420, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30604607

RESUMO

Developing multifunctional therapeutic and diagnostic (theranostic) nanoplatforms is critical for addressing challenging issues associated with cancers. Here, self-assembled supernanoparticles consisting of superparamagnetic Fe3O4 nanoparticles and photoluminescent PbS/CdS quantum dots whose emission lies within the second biological window (II-BW) are developed. The proposed self-assembled Fe3O4 and PbS/CdS (II-BW) supernanoparticles [SASNs (II-BW)] exhibit outstanding photoluminescence detectable through a tissue as thick as 14 mm, by overcoming severe light extinction and concomitant autofluorescence in II-BW, and significantly enhanced T2 relaxivity (282 mM-1 s-1, ca. 4 times higher than free Fe3O4 nanoparticles) due to largely enhanced magnetic field inhomogeneity. On the other hand, SASNs (II-BW) possess the dual capacity to act as both magnetothermal and photothermal agents, overcoming the main drawbacks of each type of heating separately. When SASNs (II-BW) are exposed to the dual-mode (magnetothermal and photothermal) heating, the thermal energy transfer efficiency is amplified 7-fold compared with magnetic heating alone. These results, in hand with the excellent photo- and colloidal stability, and negligible cytotoxicity, demonstrate the potential use of SASNs (II-BW) for deep-tissue bimodal (magnetic resonance and photoluminescence) in vivo imaging, while simultaneously providing the possibility of SASNs (II-BW)-mediated amplified dual-mode heating treatment for cancer therapy.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas Metálicas/química , Neoplasias Experimentais/diagnóstico por imagem , Animais , Compostos de Cádmio/química , Feminino , Compostos Férricos/química , Células HeLa , Humanos , Chumbo/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/terapia , Fototerapia/métodos , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Sulfetos/química , Nanomedicina Teranóstica/métodos
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