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1.
Cell Physiol Biochem ; 53(3): 453-464, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448885

RESUMO

BACKGROUND/AIMS: Eryptosis, the suicidal death of red blood cells (RBCs), is characterized by phosphatidylserine (PS) exposure at the cell surface. It can be catalysed by a variety of abnormal conditions and diseases. Until now, the many questions surrounding the physiology and pathophysiology of eryptosis have not been sufficiently answered. Recently, we demonstrated IgM and IgA autoantibodies (aab) to induce PS exposure on circulating RBCs of patients with autoimmune haemolytic anaemia (AIHA). However, it remained unclear how these aab lead to eryptosis. METHODS: Serum and plasma samples from patients with clinically relevant AIHA of cold type were used to induce eryptosis in O RBCs. Serum containing fresh complement from healthy donors, antibodies to complement component, and complement factor depleted sera were added to examine the influence of the complement on PS-exposure. RBC bound annexin V PE were analysed by flow cytometry. RESULTS: Eryptosis related to IgM aab was found to be dependent on complement activation and could be effectively inhibited by EDTA, serum heat inactivation and anti-C5. PS exposure increased with sequential activation of the sublytic terminal complement components C5b6, C5b-7 and was most significant at the C5b-8 stage. A decrease was observed following the formation of the lytic membrane attack complex C5b-9, either because of lysis of eryptotic RBCs or because of inhibition of eryptosis by C9. CONCLUSION: Our findings reflect new aspects on RBC destruction in AIHA as well the impact of the terminal complement complexes on the RBC membrane. The striking differences to nucleated cell apoptosis may even have physiological meaning of RBC acting as a buffer of the complement system.


Assuntos
Anemia Hemolítica Autoimune/patologia , Autoanticorpos/farmacologia , Proteínas do Sistema Complemento/metabolismo , Eriptose/efeitos dos fármacos , Imunoglobulina M/imunologia , Anemia Hemolítica Autoimune/sangue , Ativação do Complemento/efeitos dos fármacos , Complemento C5/metabolismo , Ácido Edético/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Fosfatidilserinas/farmacologia
2.
Bol. latinoam. Caribe plantas med. aromát ; 18(4): 359-377, jul. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1008174

RESUMO

Plant species have been used for therapeutic purposes since ancient times and are still in use today since these products represent a source of raw material for the production of phytotherapeutic formulations. Screening and investigation of plants with pharmacological potential require the evaluation of characteristics related to their action, efficacy and safety in different steps. Among these steps, pre- clinical trials are used to evaluate the properties of the test product in in vitro experiments, such as cytotoxicity assays. Within this context, this study consists of a bibliometric analysis of some in vitro cytotoxicity and toxicity assays in erythrocytes used during bioprospecting of medicinal plants. The results demonstrated the wide application of erythrocytes to evaluate the biological effects of medicinal plant extracts. The methods were found to be valid and effective for the preliminary investigation of the in vitro cytotoxicity and toxicity of plant products.


El uso de especies vegetales para fines terapéuticos es una práctica histórica y todavía bastante actual, ya que estos productos pueden representar una fuente de materia prima para la producción de formulaciones fitoterápicas. En investigación de plantas con potencial farmacológico requiere la evaluación de su acción, eficacia y seguridad, a través de diferentes etapas. Entre estas, en los ensayos preclínicos se evalúan las propiedades del producto-prueba en experimentos in vitro, tales como ensayos de citotoxicidad, entre otros. En este aspecto, el presente estudio consiste en un análisis bibliométrico acerca de algunas pruebas de citotoxicidad y toxicidad in vitro en eritrocitos realizados en los ensayos de bioprospección de plantas medicinales. Los resultados evidencian la amplia utilización de eritrocitos para la evaluación de los efectos biológicos de extractos de plantas medicinales, apuntándolos como métodos válidos y eficaces para la investigación preliminar de la citotoxicidad y toxicidad in vitro de productos vegetales.


Assuntos
Bioensaio/métodos , Extratos Vegetais/toxicidade , Eritrócitos/efeitos dos fármacos , Antioxidantes/toxicidade , Fragilidade Osmótica , Estresse Oxidativo , Eritrócitos/citologia , Bioprospecção , Hemólise/efeitos dos fármacos
3.
Cell Physiol Biochem ; 53(1): 186-199, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31278696

RESUMO

BACKGROUND/AIMS: Estrogen could play a key role in the mechanisms underlying sex-related disparity in the incidence of thrombotic events. We investigated whether estrogen receptors (ERs) were expressed in human red blood cells (RBCs), and if they affected cell signaling of erythrocyte constitutive isoform of endothelial NO-synthase (eNOS) and nitric oxide (NO) release. METHODS: RBCs from 29 non-smoker volunteers (15 males and 14 females) aged between 20 and 40 years were analyzed by cytometry and western blot. In particular, content and distribution of ER-α and ER-ß, tyrosine kinases and eNOS phosphorylation and NO release were analyzed. RESULTS: We demonstrated that: i) both ER-α and ER-ß were expressed by RBCs; ii) they were both functionally active; and iii) ERs distribution and function were different in males and females. In particular, ERs modulated eNOS phosphorylation and NO release in RBCs from both sexes, but they induced the phosphorylation of specific tyrosine residues of kinases linked to eNOS activation and NO release in the RBCs from females only. CONCLUSION: Collectively, these data suggest that ERs could play a critical role in RBC intracellular signaling. The possible implication of this signaling in sex-linked risk disparity in human cardiovascular diseases, e.g. in thrombotic events, may not be ruled out.


Assuntos
Receptores Estrogênicos/metabolismo , Transdução de Sinais , Adulto , Dronabinol/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Piperidinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
4.
Chem Pharm Bull (Tokyo) ; 67(7): 666-674, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257322

RESUMO

Dimeric sesquiterpene thioalkaloids from the rhizomes of Nuphar pumilum exhibited immunosuppressive effects using a sheep erythrocyte plaque forming cell (PFC) assay, as well as an anti-metastasis effect, and rapid apoptosis-inducing effects in tumor cell lines. In particular, dimeric sesquiterpene thioalkaloids with a hydroxy group (6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B) showed substantial effects, whereas dimeric sesquiterpene thioalkaloids lacking the hydroxy group (thiobinupharidine, thionuphlutine B, 6'-hydroxythionuphlutine B, neothiobinupharidine, thionuphlutine B ß-sulfoxide, neothiobinupharidine ß-sulfoxide) and monomeric sesquiterpene alkaloids (nupharidine, 7-epideoxynupharidine, nupharolutine) showed weak activity. In this review, we summarize our studies of the biofunctional effects of these alkaloids.


Assuntos
Alcaloides/química , Nuphar/química , Sesquiterpenos/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Imunossupressores/química , Imunossupressores/isolamento & purificação , Imunossupressores/farmacologia , Nuphar/metabolismo
5.
Cell Physiol Biochem ; 53(1): 229-241, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31302949

RESUMO

BACKGROUND/AIMS: Circulating or extracellular histones (EHs) in the bloodstream act as a damage-associated-molecular-pattern (DAMP) agent that plays a critical role in the pathogenesis of many diseases such as sepsis and sterile inflammation. To date, not much information is available to describe the mechanistic relationship between human erythrocytes and the cytotoxicity of EHs, the protein members from a highly conserved histone family across species. The present study explored this key question with a hypothesis that EHs induce eryptosis. METHODS: Freshly isolated human red blood cells (RBCs) from healthy donors were treated with EHs or agents for positive controls in a physiological buffer for 3 or 24 h. After treatments, flow cytometry was employed to quantify surface phosphatidylserine (PS) exposure from annexin-V-RFP binding, cell shrinkage from flow cytometric forward scatter (FSC) analysis, Ca2+ rise by fluo-4, reactive oxygen species (ROS) production by H2DCFDA, and caspase-3 activation by FAM-DEVD-FMK measurement. Hemolysis and membarne permeabilization were estimated respectively from hemoglobin release into supernatant and calcein leakage from RBC ghosts. RESULTS: With positive controls for validation, EHs in the pathophsyiological range were found to accumulate annexin-V binding on cell surface, decrease FSC, upregulate ROS production, elevate Ca2+ influx and increase caspase-3 activity in a 3-h incubation. Of note, no RBC hemolysis and no calcein release from ghosts were obtained after EHs treatment for 24 h. Interestingly, external Ca2+ was not a prerequisite for the EHs-mediated ROS production and PS externalization. Also, the eryptotic hallmarks in the apoptotic RBCs were partially blocked by heparin and antibody (Ab) against Toll-like receptor 2 (TLR2). CONCLUSION: EHs act as a DAMP agent in the human RBCs that induces eryptosis. The cytotoxic effect is rapid as the hallmarks of eryptosis such as cell shrinkage, surface PS exposure, [Ca2+]i rise, ROS production and caspase-3 activation can be seen 3 h after treatment in a dose-dependent manner. The EHs' cytotoxic effects could be blocked by heparin and the Ab against TLR2.


Assuntos
Eriptose/efeitos dos fármacos , Histonas/farmacologia , Anticorpos/imunologia , Anticorpos/farmacologia , Cálcio/metabolismo , Caspase 3/metabolismo , Células Cultivadas , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Heparina/farmacologia , Humanos , Espécies Reativas de Oxigênio/metabolismo , Receptor 2 Toll-Like/imunologia
6.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
7.
J Med Microbiol ; 68(7): 1003-1011, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31172912

RESUMO

PURPOSE: The present study aimed to establish pretreatment protocols as well as real-time and droplet digital polymerase chain reaction (PCR) methodologies to detect and quantify Erysipelothrix rhusiopathiae (ER) DNA in blood samples from infected chickens, as tools for routine diagnostics and monitoring of experimental infections. Chicken blood is a problematic matrix for PCR analysis because nucleated erythrocytes contribute large amounts of host DNA that inhibit amplification. METHODOLOGY: Using artificially spiked samples of fresh chicken blood, as well as blood samples from three experimental infection studies, the performance of pretreatment protocols, including choice of blood stabilization agent, centrifugation speeds and Ficoll gradient separation, was evaluated. The results were compared with those from traditional culture-based protocols combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).Results/Key findings. Simple preparations producing cell-free samples performed well on artificial spike-in samples, providing high sensitivity. However, performance was poor in clinical samples or artificial samples where the bacteria were incubated for 4 h or more in fresh blood prior to DNA extraction. In these samples, a Ficoll separation protocol that creates samples rich in lymphocytes, monocytes and thrombocytes prior to DNA extraction was far more effective. CONCLUSIONS: Our results indicate that ER bacteria undergo rapid phagocytosis in chicken blood and that analysis of a blood fraction enriched for phagocytic cells is necessary for reliable detection and quantification. The presented results explain the poor performance of PCR detection reported in previously published experimental ER infection studies, and the proposed solutions are likely to have broader implications for PCR-based veterinary diagnostics in non-mammalian host species such as poultry and fish.


Assuntos
Galinhas/microbiologia , DNA Bacteriano/genética , Infecções por Erysipelothrix/microbiologia , Erysipelothrix/genética , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Erysipelothrix/isolamento & purificação , Infecções por Erysipelothrix/diagnóstico , Eritrócitos/citologia , Eritrócitos/microbiologia , Reação em Cadeia da Polimerase/métodos
8.
Soft Matter ; 15(27): 5511-5520, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241632

RESUMO

Red blood cells in shear flow show a variety of different shapes due to the complex interplay between hydrodynamics and membrane elasticity. Malaria-infected red blood cells become generally adhesive and less deformable. Adhesion to a substrate leads to a reduction in shape variability and to a flipping motion of the non-spherical shapes during the mid-stage of infection. Here, we present a complete state diagram for wall adhesion of red blood cells in shear flow obtained by simulations, using a particle-based mesoscale hydrodynamics approach, multiparticle collision dynamics. We find that cell flipping at a substrate is replaced by crawling beyond a critical shear rate, which increases with both membrane stiffness and viscosity contrast between the cytosol and suspending medium. This change in cell dynamics resembles the transition between tumbling and tank-treading for red blood cells in free shear flow. In the context of malaria infections, the flipping-crawling transition would strongly increase the adhesive interactions with the vascular endothelium, but might be suppressed by the combined effect of increased elasticity and viscosity contrast.


Assuntos
Eritrócitos/citologia , Eritrócitos/fisiologia , Adesão Celular , Movimento Celular , Forma Celular , Simulação por Computador , Elasticidade , Membrana Eritrocítica/fisiologia , Cinética , Fenômenos Físicos , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Viscosidade
9.
Oxid Med Cell Longev ; 2019: 3435174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049132

RESUMO

Uric acid (UA) is a major antioxidant molecule in the human blood, and it has been linked with cell longevity. However, it is unclear whether serum UA levels are associated with red blood cell (RBC) indexes. This cross-sectional study included 10,759 Chinese subjects, recruited from the Shanghai Xuhui Central Hospital from January 2014 to December 2017. The participants were categorized into gender groups and then further divided into three different subgroups according to their UA reference range as follows: low (male (UA < 0.202 mmol/l), female (UA < 0.143 mmol/l)), normal (male (0.417 mmol/l > UA ≥ 0.202 mmol/l), female (0.339 mmol/l > UA ≥ 0.143 mmol/l)), and high (male (UA ≥ 0.417 mmol/l), female (UA ≥ 0.339 mmol/l)). The associations of UA levels with RBC parameters were analyzed using 1-way ANOVA, Pearson correlations, and multivariate linear regression. The levels of mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, RBCs, and hemoglobin were lowest in the low UA group, followed by the normal UA group and high UA group (p < 0.001). Pearson analysis showed that there was a statistically significant correlation between UA levels with mean corpuscular hemoglobin, mean corpuscular hemoglobin concentrations, mean corpuscular volumes, RBC counts, and hemoglobin (p < 0.05). Multiple linear regression analysis suggested that there were statistically significant positive correlations between UA levels and RBC counts (B = 0.245, p < 0.001, 95% CI = 0.003 to 0.092), as well as UA levels and hemoglobin concentrations (B = 0.138, p < 0.001, 95% CI = 0.002 to 0.082). Furthermore, similar results were observed in both the male and female subgroups. The serum UA levels may be independently associated with RBC parameters, regardless of sex, and UA may protect RBCs owing to its antioxidant effect.


Assuntos
Antioxidantes/metabolismo , Eritrócitos/metabolismo , Caracteres Sexuais , Ácido Úrico/sangue , Adulto , Idoso , Estudos Transversais , Contagem de Eritrócitos , Eritrócitos/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Fish Shellfish Immunol ; 90: 376-384, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31048039

RESUMO

The grass carp (Ctenopharyngodon idella), blunt snout bream (Megalobrama amblycephala) and yellow catfish (Pelteobagrus fulvidraco) are economically important fishes in China. Fish hematological features, especially the type and number of peripheral blood cells, are crucial for the evaluation of fish health and the diagnosis of fish diseases. Since the automatic blood cell count equipment for human is not suitable for fishes, the manual method is critical in the quantification of fish blood cells. To make sense of the comparison and interpretation of the blood cell count studies in different articles, the standardization of blood cell classification is necessary. In this study, erythrocytes (red blood cell, RBC), thrombocytes (TC) and leucocytes (i.e. white blood cells, WBC, including lymphocytes, neutrophils and monocytes) were well distinguished in blood smears with Giemsa staining and confirmed by transmission electron microscopy. RBC, TC and WBC were directly counted with an improved Neubauer counting chamber in a modified diluting solution. The differential leucocyte count (DLC) was carried out in blood smears. In view of the labeling characteristics of peroxidase (PO) positivity in neutrophils and non-specific esterase (α-ANAE) positivity in monocytes, PO positive cell percentage and α-ANAE positive cell percentage were also determined in cytochemistry staining smears. No difference was found for the percentages of neutrophils and monocytes between Giemsa staining and cytochemistry staining. The standardized classification, normal count ranges and sizes of the peripheral blood cells by the present systemic studies will provide useful references for monitoring the health status of grass carp, blunt snout bream and yellow catfish.


Assuntos
Contagem de Células Sanguíneas/veterinária , Carpas/sangue , Peixes-Gato/sangue , Cyprinidae/sangue , Animais , Corantes Azur , Plaquetas/citologia , China , Eritrócitos/citologia , Leucócitos/citologia , Microscopia Eletrônica de Transmissão/veterinária , Valores de Referência
11.
Molecules ; 24(9)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060332

RESUMO

Hair-coloring products include permanent, semi-permanent and temporary dyes that vary by chemical formulation and are distinguished mainly by how long they last. Domestic temporary hair dyes, such as fuchsin basic, basic red 2 and Victoria blue B, are especially popular because of their cheapness and facile applications. Despite numerous studies on the relationship between permanent hair dyes and disease, there are few studies addressing whether these domestic temporary hair dyes are associated with an increased cancer risk. Herein, to ascertain the bio-safety of these temporary hair dyes, we comparatively studied their percutaneous absorption, hemolytic effect and cytotoxic effects in this paper. Furthermore, to better understand the risk of these dyes after penetrating the skin, experimental and theoretical studies were carried out examining the interactions between the dyes and serum albumins as well as calf thymus (CT)-DNA. The results showed that these domestic temporary hair dyes are cytotoxic with regard to human red blood cells and NIH/3T3 cell lines, due to intense interactions with bovine serum albumin (BSA)/DNA. We conclude that the temporary hair dyes may have risk to human health, and those who use them should be aware of their potential toxic effects.


Assuntos
Eritrócitos/citologia , Tinturas para Cabelo/efeitos adversos , Células NIH 3T3/citologia , Corantes de Rosanilina/efeitos adversos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Tinturas para Cabelo/química , Tinturas para Cabelo/farmacocinética , Hemólise , Humanos , Camundongos , Simulação de Acoplamento Molecular , Células NIH 3T3/efeitos dos fármacos , Fenazinas/efeitos adversos , Fenazinas/química , Fenazinas/farmacocinética , Corantes de Rosanilina/química , Corantes de Rosanilina/farmacocinética , Albumina Sérica Humana/efeitos dos fármacos , Suínos
12.
Artif Cells Nanomed Biotechnol ; 47(1): 1888-1897, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31072140

RESUMO

Storage lesions in red blood cells (RBCs) hinder efficient circulation and tissue oxygenation. The absence of flow mechanics and gas exchange may contribute to this problem. To test if in vitro compensation of flow mechanics and gas exchange helps RBC recovery, three-dimensional polydimethylsiloxane (PDMS) porous structures were fabricated with a sugar mould, simulating lung alveoli. RBC suspensions were passed through the porous structure cyclically, simulating in vivo blood circulation. Acid-base indices, partial gas pressures, ions, glucose and RBC indices were analyzed. An atomic force microscope was used to investigate local mechanical properties of intact RBCs. RBCs suspensions that passed through the porous structures had a higher pH and oxygen partial pressure, and a lower potassium concentration and carbon dioxide partial pressure. Meantime they had better biochemical properties relative to static samples, namely, they exhibited a more homogenous distribution of Young's Modulus. RBCs that passed through a PDMS porous structure were healthier than static ones, giving hints to prevent RBC storage lesions.


Assuntos
Preservação de Sangue , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Eritrócitos/efeitos dos fármacos , Gases/metabolismo , Hemorreologia/efeitos dos fármacos , Nylons/química , Nylons/farmacologia , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Módulo de Elasticidade/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/metabolismo , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Masculino , Porosidade , Ratos , Ratos Wistar
13.
Bioelectrochemistry ; 128: 204-210, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31005816

RESUMO

Synchronized data from ion currents and optical microscopy have been used to measure the mechanical properties of individual soft microparticles. This new experimental method draws on the signals generated by each particle as it passes through the tip of a pipette. The technique represents an advance on micropipette aspiration (MA), which uses optical microscopy in isolation. The ionic resistance through the tip provides additional information regarding the progress of particle deformation. The augmented technique is demonstrated by studying aspiration of individual bovine erythrocytes into a micropipette. Effective mechanical properties have been deduced by using the ionic current response to measure the dwell time and velocity of erythrocytes. Values obtained for the effective viscosity represent liquid-like deformation of the whole cell, and show a consistent shear thinning effect. The effective elasticity also varies with applied force, and was higher for erythrocytes stored for several weeks. The data show that wall friction is an important factor for the uptake dynamics, and that the erythrocytes were damaged or ruptured when passing through pipettes of opening diameter 0.7 µm, the smallest used. These results demonstrate a new approach to measuring the mechanics of individual bioparticles.


Assuntos
Equipamentos e Provisões , Deformação Eritrocítica , Eritrócitos/citologia , Animais , Fenômenos Biomecânicos , Bovinos , Elasticidade , Transporte de Íons , Viscosidade
14.
Phys Rev Lett ; 122(12): 128002, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30978078

RESUMO

Microflows constitute an important instrument to control particle dynamics. A prominent example is the sorting of biological cells, which relies on the ability of deformable cells to move transversely to flow lines. A classic result is that soft microparticles migrate in flows through straight microchannels to an attractor at their center. Here, we show that flows through wavy channels fundamentally change the overall picture. They lead to the emergence of a second, coexisting attractor for soft particles. Its emergence and off-center location depends on the boundary modulation and the particle properties. The related cross-stream migration of soft particles is explained by analytical considerations, Stokesian dynamics simulations in unbounded flows, and Lattice-Boltzmann simulations in bounded flows. The novel off-center attractor can be used, for instance, in diagnostics, for separating cells of different size and elasticity, which is often an indicator of their health status.


Assuntos
Eritrócitos/citologia , Modelos Biológicos , Movimento Celular/fisiologia , Eritrócitos/química , Microfluídica
15.
Mater Sci Eng C Mater Biol Appl ; 100: 94-103, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948130

RESUMO

Various glucose-sensitive drug delivery platforms have been developed recently to treat diabetes. However, there is much less work has been reported on treatment of diabetes and vascular diabetes complications simultaneously. In this work, a novel polysaccharide-based micelle-hydrogel synergistic therapy system was fabricated to address this limitation. Zwitterionic dialdehyde starch-based micelles (SB-DAS-VPBA) were synthesized via single electron transfer-living radical polymerization (SET-LRP). Hydrophilic segment sulfobetaine (SB) and hydrophobic segment 4­vinylphenylboronic acid (VPBA) were grafted to the dialdehyde starch (DAS) backbones. Then, chitosan/dialdehyde starch derivatives (CS/SB-DAS-VPBA) micelle-hydrogel was synthesized by Schiff-base bonds. Insulin and nattokinase were loaded to obtain the micelle-hydrogel synergistic therapy system. In vitro drug delivery and blood clots dissolution behaviors were determined. Results suggest that the micelle-hydrogel synergistic therapy system not only possesses glucose-responsive insulin delivery property, but also provides good thrombolytic capacity. Thus, this micelle-hydrogel synergistic therapy system can be used as a platform for diabetes and vascular diabetes complications treatment.


Assuntos
Hidrogéis/química , Micelas , Amido/análogos & derivados , Betaína/análogos & derivados , Betaína/química , Ácidos Borônicos/química , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Hidrogéis/farmacologia , Amido/química , Compostos de Vinila/química
16.
ACS Appl Mater Interfaces ; 11(17): 15262-15275, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964624

RESUMO

Nanoparticles camouflaged by red blood cell (RBC) membranes have attracted considerable attention owing to reservation of structure of membrane and surface proteins, endowing prominent cell-specific function including biocompatibility, prolonged circulation lifetime, and reduced reticular endothelial system (RES) uptake ability. Considering the drawbacks of carrier-free nanomedicine including the serious drug burst release, poor stability, and lack of immune escape function, herein we developed and fabricated a novel RBC membranes biomimetic combinational therapeutic system by enveloping the small molecular drug coassemblies of 10-hydroxycamptothecin (10-HCPT) and indocyanine green (ICG) in the RBC membranes for prolonged circulation, controlled drug release, and synergistic chemo-photothermal therapy (PTT). The self-reorganized RBCs@ICG-HCPT nanoparticles (NPs) exhibited a diameter of ∼150 nm with core-shell structure, high drug payload (∼92 wt %), and reduced RES uptake function. Taking advantage of the stealth functionality of RBC membranes, RBCs@ICG-HCPT NPs remarkably enhanced the accumulation at the tumor sites by passive targeting followed by cellular endocytosis. Upon the stimuli of near-infrared laser followed by acidic stimulation, RBCs@ICG-HCPT NPs showed exceptional instability by heat-mediated membrane disruption and pH change, thereby triggering the rapid disassembly and accelerated drug release. Consequently, compared with individual treatment, RBCs@ICG-HCPT NPs under dual-stimuli accomplished highly efficient apoptosis in cancer cells and remarkable ablation of tumors by chemo-PTT. This biomimetic nanoplatform based on carrier-free, small molecular drug coassemblies integrating imaging capacity as a promising theranostic system provides potential for cancer diagnosis and combinational therapy.


Assuntos
Antineoplásicos Fitogênicos/química , Biomimética , Camptotecina/análogos & derivados , Membrana Celular/química , Raios Infravermelhos , Nanopartículas/química , Neoplasias/terapia , Animais , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Camptotecina/química , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Eritrócitos/citologia , Eritrócitos/metabolismo , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Verde de Indocianina/química , Masculino , Camundongos , Camundongos Nus , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fototerapia , Ratos , Ratos Sprague-Dawley
17.
Nanoscale ; 11(16): 7850-7856, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30964133

RESUMO

Activated carbon nanodots functionalized with acid anhydride groups (AA-CNDs) are prepared by one-pot water-free green thermolysis of citric acid. As a proof of concept of their capabilities as appealing and versatile platforms for accessing engineering nanoconstructs, the as-prepared AA-CNDs have been reacted to yield clickable CNDs. Their click bioconjugation with relevant recognizable complementary clickable sugars has led to multivalent CND-based glyconanoparticles that are non-toxic and biorecognizable. The accessibility and intrinsic reactivity of AA-CNDs expand the current toolbox of covalent surface grafting methodologies and provide a wide range of potential applications for engineering (bio)nanoconstructs.


Assuntos
Anidridos/química , Carbono/química , Nanoestruturas/química , Animais , Linhagem Celular , Ácido Cítrico/química , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Microscopia Confocal , Nanoestruturas/toxicidade , Pirólise
18.
Contrast Media Mol Imaging ; 2019: 4368342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019414

RESUMO

The scintigraphy with radiolabelled autologous leukocytes (WBCs) is considered the gold-standard technique for imaging infections. Leukokit® is a commercially available, disposable, sterile kit for labelling WBCs ex vivo. In this kit, WBCs isolation from red blood cells (RBCs) was performed using poly(O-2-hydroxyethyl)starch (HES) as the RBCs sedimentation agent. Due to its poor availability, HES has been recently replaced by Gelofusine as the RBC sedimentation agent. The aim of this study was to compare the labelling efficiency and the diagnostic accuracy of WBCs labelled with Leukokit® with HES vs Leukokit® with Gelofusine. WBCs were isolated using HES or Gelofusine for 45 minutes and then purified from platelets (PLTs) and labelled with 1.1 ± 0.3 GBq of freshly prepared 99mTc-HMPAO. The following parameters were evaluated: the number and type of recovered WBCs, RBCs contamination, PLTs contamination, vitality of neutrophils, and chemotactic properties of neutrophils. Clinical comparison was performed between 80 patients (33 males; age 67.5 ± 14.2) injected with 99mTc-HMPAO-WBCs, using HES as the sedimentation agent, and 92 patients (38 males; age 68.2 ± 12.8) injected with 99mTc-HMPAO-WBCs using Gelofusine as the sedimentation agent. Patients were affected by prosthetic joint infections, peripheral bone osteomyelitis, or vascular graft infection. We compared radiolabelling efficiency (LE), final recovery yield (RY), and diagnostic outcome based on microbiology or 2-year follow-up. Results showed that HES provides the lowest RBCs and PLTs contamination, but Gelofusine provides the highest WBC recovery. Both agents did not influence the chemotactic properties of WBCs, and no differences were found in terms of LE and RY. Sensitivity, specificity, and accuracy were also not significantly different for WBCs labelled with both agents (diagnostic accuracy 90.9%, CI = 74.9-96.1 vs 98.3%, CI = 90.8-100, for HES and Gelofusine, respectively). In conclusion, Gelofusine can be considered a suitable alternative of HES for WBCs separation and labelling.


Assuntos
Poligelina/química , Tecnécio Tc 99m Exametazima/química , Idoso , Idoso de 80 Anos ou mais , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Feminino , Granulócitos/citologia , Granulócitos/efeitos dos fármacos , Humanos , Marcação por Isótopo/métodos , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
19.
Klin Lab Diagn ; 64(3): 176-179, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31012557

RESUMO

There are cases of discrepancies between the results of a microscopic examination of blood cells by morphological physicians with data obtained using an automatic analyzer in patients with a hematologic profile. It is shown that in some cases the analyzer does not determine changes in the morphology of erythrocytes, allows errors in calculating the leukoformula, differentiation of cells according to the degree of maturity, and evaluation of the number of platelets. The complementary importance of methods of light microscopy and automated blood analysis in patients with suspected pathology of the blood system is underlined.


Assuntos
Plaquetas/citologia , Eritrócitos/citologia , Testes Hematológicos , Microscopia , Automação Laboratorial , Humanos
20.
Chem Commun (Camb) ; 55(31): 4562-4565, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30931453

RESUMO

In this report, we designed and synthesized a novel fluorescent single tailed surfactant (termed FEDS), which can disrupt endosomes, complex lipofectamine, and can also identify cells that have been transfected. FEDS was able to increase the gene editing efficiency of lipofectamine/Cas9 ribonucleoprotein by 300% via a combination of fluorescent based enrichment and endosomal disruption.


Assuntos
Proteína 9 Associada à CRISPR/genética , Edição de Genes/métodos , Lipídeos/química , Animais , Linhagem Celular , Endossomos/metabolismo , Eritrócitos/citologia , Eritrócitos/metabolismo , Citometria de Fluxo , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Coelhos
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