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Autoimmunity, allergy, and transplant rejection are a collection of chronic diseases that are currently incurable, drastically decrease patient quality of life, and consume considerable health care resources. Underlying each of these diseases is a dysregulated immune system that results in the mounting of an inflammatory response against self or an innocuous antigen. As a consequence, afflicted patients are required to adhere to lifelong regimens of multiple immunomodulatory drugs to control disease and reclaim agency. Unfortunately, current immunomodulatory drugs are associated with a myriad of side effects and adverse events, such as increased risk of cancer and increased risk of serious infection, which negatively impacts patient adherence rates and quality of life. The field of immunoengineering is a new discipline that aims to harness endogenous biological pathways to thwart disease and minimize side effects using novel biomaterial-based strategies. We highlight and discuss polymeric micro/nanoparticles with inherent immunomodulatory properties that are currently under investigation in biomaterial-based therapies for treatment of autoimmunity, allergy, and transplant rejection.
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Autoimunidade , Rejeição de Enxerto , Hipersensibilidade , Polímeros , Humanos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Polímeros/química , Autoimunidade/efeitos dos fármacos , Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Animais , Materiais Biocompatíveis/química , Nanopartículas/química , Doenças Autoimunes/terapia , Doenças Autoimunes/imunologia , Agentes de Imunomodulação/uso terapêutico , Fatores Imunológicos/uso terapêuticoRESUMO
Food fortification is an effective strategy to address vitamin A (VitA) deficiency, which is the leading cause of childhood blindness and drastically increases mortality from severe infections. However, VitA food fortification remains challenging due to significant degradation during storage and cooking. We utilized an FDA-approved, thermostable, and pH-responsive basic methacrylate copolymer (BMC) to encapsulate and stabilize VitA in microparticles (MPs). Encapsulation of VitA in VitA-BMC MPs greatly improved stability during simulated cooking conditions and long-term storage. VitA absorption was nine times greater from cooked MPs than from cooked free VitA in rats. In a randomized controlled cross-over study in healthy premenopausal women, VitA was readily released from MPs after consumption and had a similar absorption profile to free VitA. This VitA encapsulation technology will enable global food fortification strategies toward eliminating VitA deficiency.
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Deficiência de Vitamina A , Vitamina A , Feminino , Ratos , Animais , Alimentos Fortificados , Estudos Cross-Over , Culinária , MicronutrientesRESUMO
Despite the continuous development of energy storage, the challenges faced by micro-silicon anode pulverization have yet to be effectively addressed. In this work, the aramid nanofibers (ANFs) are in situ protonated on the surface of silicon micro-particles (SMPs), and also act as surfactants to bundle the carbon nanotubes (CNTs) to form ANF/CNT networks on SMPs (ANF/CNT/SMPs) at the same time. The results demonstrate that the dual-coating not only inhibits expansion and enhances structural stability but also improves conductivity, thereby promoting the cycling stability of micro-silicon anodes. The ANF/CNT/SMP anode shows cycling stability of 454 mAh g-1 at 0.2 A g-1 after 200 cycles. The expansion in thickness of the ANF/CNT/SMP electrode can be reduced by 51.5% after 100 cycles compared with the SMP electrode. The findings provide a novel approach for mitigating expansion in micro-silicon anodes through the combined coating of ANFs and CNTs.
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Stem cell-related therapeutic technologies have garnered significant attention of the research community for their multi-faceted applications. To promote the therapeutic effects of stem cells, the strategies for cell microencapsulation in hydrogel microparticles have been widely explored, as the hydrogel microparticles have the potential to facilitate oxygen diffusion and nutrient transport alongside their ability to promote crucial cell-cell and cell-matrix interactions. Despite their significant promise, there is an acute shortage of automated, standardized, and reproducible platforms to further stem cell-related research. Microfluidics offers an intriguing platform to produce stem cell-laden hydrogel microparticles (SCHMs) owing to its ability to manipulate the fluids at the micrometer scale as well as precisely control the structure and composition of microparticles. In this review, the typical biomaterials and crosslinking methods for microfluidic encapsulation of stem cells as well as the progress in droplet-based microfluidics for the fabrication of SCHMs are outlined. Moreover, the important biomedical applications of SCHMs are highlighted, including regenerative medicine, tissue engineering, scale-up production of stem cells, and microenvironmental simulation for fundamental cell studies. Overall, microfluidics holds tremendous potential for enabling the production of diverse hydrogel microparticles and is worthy for various stem cell-related biomedical applications.
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Hidrogéis , Microfluídica , Células-Tronco , Células-Tronco/citologia , Microfluídica/métodos , Hidrogéis/química , Humanos , Engenharia Tecidual/métodos , AnimaisRESUMO
The aim of this study was to investigate the interference of lipemia on measurement of HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc, anti-HCV, HIV Ag/Ab, and anti-TP in serum by chemiluminescent microparticle immunoassay (CMIA) and compare lipemia removing performance between high-speed centrifugation and Lipoclear reagent. Mixed native serum samples (NSs) and hyperlipemia serum samples (HLS) were prepared for the investigated parameters. The levels of these parameters in NS and HLS were determined by CMIA on an Abbott ARCHITECT i2000SR immunoassay analyzer. HBsAg, anti-HBs, and anti-TP were affected with relative bias >12.5% (acceptable limit) when the level of triacylglycerol (TG) was higher than 27.12 mmol/L in HLS. Clinically unacceptable bias were observed for HBeAg and anti-HBe in HLS with TG higher than 40.52 mmol/L. However, anti-HCV and HIV Ag/Ab were not interfered in severe lipemia with TG < 52.03 mmol/L. In addition, the Lipoclear reagent did not reduce the interference of lipemia with relative bias from -62.50% to -18.02%. The high-speed centrifugation under the optimized condition of 12 000g for 10 min successfully removed the interference of lipemia with relative bias from -5.93% to 0% for HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc, and anti-TP. To conclude, high-speed centrifugation can be used for removing the interference of lipemia to measure HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc, and anti-TP. Accordingly, a standardized sample preanalytical preparation of the patients and other screening participants as well as a specimen examination procedure for removing lipemia interference on the serological tests was recommended.
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Síndrome da Imunodeficiência Adquirida , Hepatite B , Hepatite C , Hiperlipidemias , Sífilis , Humanos , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Indicadores e Reagentes , Sífilis/diagnóstico , Vírus da Hepatite B , Anticorpos Anti-Hepatite B , Imunoensaio , Hepatite C/diagnóstico , Testes Sorológicos , Triglicerídeos , CentrifugaçãoRESUMO
Dielectrophoresis (DEP) is an electrokinetic effect first studied in the early 20th century. Since then, DEP has gained significant interest in research, owing to its ability to solve particle separation problems in various industries. Dielectrophoretic filtration (DEP filtration) is a separation method using DEP to filter a wide range of microparticles, from bacterial cells to catalytic particles. DEP filtration can selectively separate particles based on size or dielectric properties, recover trapped particles and avoid common problems associated with mechanical filtration based on pore size (e.g. pressure drops and regular filter replacements). This review describes the simple beginnings of DEP filtration and how our understanding and applications for DEP filtration have progressed over time. A brief section of DEP theory as well as a note on the general outlook for DEP filtration in the future is presented. DEP filtration offers an exciting opportunity to selectively separate diverse particle mixtures. To achieve such a feat, technical challenges such as Joule Heating and low throughputs must be addressed.
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Methods for culturing oxygen-sensitive cells and organisms under anaerobic conditions are vital to biotechnology research. Here, we report a biomaterial-based platform for anaerobic culture that consists of glucose oxidase (GOX) functionalized alginate microparticles (ALG-GOX), which are designed to deplete dissolved [O2 ] through enzymatic activity. ALG-GOX microparticles were synthesized via a water-in-oil emulsion and had a size of 132.0 ± 51.4 µm. Despite having a low storage modulus, the microparticles remained stable under aqueous conditions due to covalent crosslinking through amide bonds. Enzyme activity was tunable based on the loaded GOX concentration, with a maximum activity of 3.6 ± 0.3 units/mg of microparticles being achieved at an initial loading concentration of 5 mg/mL of GOX in alginate precursor solution. High enzyme activity in ALG-GOX microparticles resulted in rapid oxygen depletion, producing a suitable environment for anaerobic culture. Microparticles loaded with both GOX and catalase (ALG-GOX-CAT) to reduce H2 O2 buildup exhibited sustained activity for potential long-term anaerobic culture. ALG-GOX-CAT microparticles were highly effective for the anaerobic culture of Bacteroides thetaiotaomicron, with 10 mg/mL of ALG-GOX-CAT microparticles supporting the same level of growth in an aerobic environment compared to an anaerobic chamber after 16 h (8.70 ± 0.96 and 10.03 ± 1.03 million CFU, respectively; N.S. p = 0.07). These microparticles could be a valuable tool for research and development in biotechnology.
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Alginatos , Técnicas de Cultura de Células , Alginatos/química , Anaerobiose , Glucose Oxidase/químicaRESUMO
Controlling the morphology of filamentous fungi is crucial to improve the performance of fungal bioprocesses. Microparticle-enhanced cultivation (MPEC) increases productivity, most likely by changing the fungal morphology. However, due to a lack of appropriate methods, the exact impact of the added microparticles on the structural development of fungal pellets is mostly unexplored. In this study synchrotron radiation-based microcomputed tomography and three-dimensional (3D) image analysis were applied to unveil the detailed 3D incorporation of glass microparticles in nondestructed pellets of Aspergillus niger from MPEC. The developed method enabled the 3D analysis based on 375 pellets from various MPEC experiments. The total and locally resolved volume fractions of glass microparticles and hyphae were quantified for the first time. At increasing microparticle concentrations in the culture medium, pellets with lower hyphal fraction were obtained. However, the total volume of incorporated glass microparticles within the pellets did not necessarily increase. Furthermore, larger microparticles were less effective than smaller ones in reducing pellet density. However, the total volume of incorporated glass was larger for large microparticles. In addition, analysis of MPEC pellets from different times of cultivation indicated that spore agglomeration is decisive for the development of MPEC pellets. The developed 3D morphometric analysis method and the presented results will promote the general understanding and further development of MPEC for industrial application.
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Aspergillus niger , Imageamento Tridimensional , Microtomografia por Raio-X , Imageamento Tridimensional/métodos , Aspergillus niger/crescimento & desenvolvimento , Microtomografia por Raio-X/métodos , Esporos Fúngicos/química , Esporos Fúngicos/citologia , Esporos Fúngicos/crescimento & desenvolvimento , Microesferas , Hifas/química , Hifas/crescimento & desenvolvimentoRESUMO
The influence of talc microparticles on metabolism and morphology of S. rimosus at various initial organic nitrogen concentrations was investigated. The shake flask cultivations were conducted in the media with yeast extract (nitrogen source) concentration equal to 1 g YE L- 1 and 20 g YE L- 1. Two talc microparticle concentrations of 5 g TALC L- 1 and 10 g TALC L- 1 were tested in microparticle-enhanced cultivation (MPEC) runs. A high nitrogen concentration of 20 g YE L- 1 promoted the development of small agglomerates (pellets) of projected area lower than 105 µm2 and dispersed pseudohyphae. A low nitrogen concentration of 1 g YE L- 1 led to the limitation of S. rimosus growth and, in consequence, the development of the smaller number of large pseudohyphal agglomerates (pellets) of projected area higher than 105 µm2 compared to the culture containing a high amount of nitrogen source. In both cases talc microparticles were embedded into pellets and caused the decrease in their sizes. The lower amount of talc (5 g TALC L- 1) usually caused the weaker effect on S. rimosus morphology and metabolite production than the higher one. This correlation between the microparticles effect on morphology and metabolism of S. rimosus was especially noticeable in the biosynthesis of oxytetracycline, 2-acetyl-2-dicarboxamide oxytetracycline (ADOTC) and spinoxazine A. Compared to the control run, in MPEC their levels increased 4-fold, 5-fold and 1.6-fold respectively. The addition of talc also improved the production of 2-methylthio-cis-zeatin, lorneic acid J and milbemycin A3.
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Nitrogênio , Streptomyces , Nitrogênio/metabolismo , Streptomyces/metabolismo , Streptomyces/crescimento & desenvolvimento , Talco/metabolismo , Meios de Cultura/química , Metabolismo SecundárioRESUMO
INTRODUCTION: Diabetic foot infection (DFI) is one of the complications of diabetes mellitus. Clindamycin (CLY) is one of the antibiotics recommended to treat DFI, but CLY given orally and intravenously still causes many side effects. METHODS: In this study, we encapsulated CLY in a bacteria sensitive microparticle system (MP-CLY) using polycaprolactone (PCL) polymer. MP-CLY was then delivered in a separable effervescent microarray patch (MP-CLY-SEMAP), which has the ability to separate between the needle layer and separable layer due to the formation of air bubbles when interacting with interstitial fluid in the skin. RESULT: The characterization results of MP-CLY proved that CLY was encapsulated in large amounts as the amount of PCL polymer used increased, and there was no change in the chemical structure of CLY. In vitro release test results showed increased CLY release in media cultured with Staphylococcus aureus bacteria and showed controlled release. The characterization results of MPCLY-SEMAP showed that the developed formula has optimal mechanical and penetration capabilities and can separate in 56 ± 5.099 s. An ex vivo dermatokinetic test on a bacterially infected skin model showed an improvement of CLY dermatokinetic profile from MP-CLY SEMAP and a decrease in bacterial viability by 99.99%. CONCLUSION: This research offers proof of concept demonstrating the improved dermatokinetic profile of CLY encapsulated in a bacteria sensitive MP form and delivered via MP-CLY-SEMAP. The results of this research can be developed for future research by testing MP-CLY-SEMAP in vivo in appropriate animal models.
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Antibacterianos , Clindamicina , Pé Diabético , Pele , Staphylococcus aureus , Clindamicina/administração & dosagem , Pé Diabético/tratamento farmacológico , Pé Diabético/microbiologia , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Pele/microbiologia , Pele/metabolismo , Poliésteres/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Administração Cutânea , Adesivo Transdérmico , Humanos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Portadores de Fármacos/químicaRESUMO
Polymer microparticle synthesis based on the surface-templated method is a simple and environmentally friendly method to produce various microparticles. Unique particles with different compositions can be fabricated by simply annealing a polymer on a liquid-repellent surface. However, there are hurdles to producing particles of homogeneous sizes with large quantities and varying the shape of particles. Here, a new approach to synthesizing multiple polymer microparticles using micropatterns with wettability contrast is presented. Polymer microparticles are formed in two steps. First, a layer of poly(sodium-4-styrenesulfonate) is deposited on the hydrophilic regions by dipping and withdrawing this micropattern from a polymer solution, and an array of microdroplets is formed. A dewetting-inducing layer on the pattern is introduced, and then target polymer patches are sequentially generated on it. By annealing over Tg, the contact line of the target polymer patch is freely receded, creating a particle form. The size and shape of the microparticle can be controlled by varying the micropatterns. In addition, it is demonstrated that microparticles made of polymer blends or polymer/nanoparticle composite are easily produced. This versatile method offers the potential of surface-templated synthesis to tailor polymer microparticles with different sizes, shapes, and functionalities in various research and applications.
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Microcarrier is a promising drug delivery system demonstrating significant value in treating cancers. One of the main goals is to devise microcarriers with ingenious structures and functions to achieve better therapeutic efficacy in tumors. Here, inspired by the nucleus-cytoplasm structure of cells and the material exchange reaction between them, we develop a type of biorthogonal compartmental microparticles (BCMs) from microfluidics that can separately load and sequentially release cyclooctene-modified doxorubicin prodrug (TCO-DOX) and tetrazine-modified indocyanine green (Tz-ICG) for tumor therapy. The Tz-ICG works not only as an activator for TCO-DOX but also as a photothermal agent, allowing for the combination of bioorthogonal chemotherapy and photothermal therapy (PTT). Besides, the modification of DOX with cyclooctene significantly decreases the systemic toxicity of DOX. As a result, the developed BCMs demonstrate efficient in vitro tumor cell eradication and exhibit notable tumor growth inhibition with favorable safety. These findings illustrate that the formulated BCMs establish a platform for bioorthogonal prodrug activation and localized delivery, holding significant potential for cancer therapy and related applications.
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Doxorrubicina , Sistemas de Liberação de Medicamentos , Verde de Indocianina , Terapia Fototérmica , Pró-Fármacos , Doxorrubicina/farmacologia , Doxorrubicina/química , Terapia Fototérmica/métodos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Animais , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular Tumoral , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Ciclo-Octanos/química , Ciclo-Octanos/farmacologia , Camundongos Endogâmicos BALB C , Antineoplásicos/farmacologia , Antineoplásicos/química , FemininoRESUMO
Immunogenic cell death (ICD) plays a crucial role in triggering the antitumor immune response in the tumor microenvironment (TME). Recently, considerable attention has been dedicated to ferroptosis, a type of ICD that is induced by intracellular iron and has been demonstrated to change the immune desert status of the TME. However, among cancers that are characterized by an immune desert, such as prostate cancer, strategies for inducing high levels of ferroptosis remain limited. Radiated tumor cell-derived microparticles (RMPs) are radiotherapy mimetics that have been shown to activate the cGAS-STING pathway, induce tumor cell ferroptosis, and inhibit M2 macrophage polarization. RMPs can also act as carriers of agents with biocompatibility. In the present study, we designed a therapeutic system wherein the ferroptosis inducer RSL-3 was loaded into RMPs, which were tested in in vitro and in vivo prostate carcinoma models established using RM-1 cells. The apoptosis inducer CT20 peptide (CT20p) was also added to the RMPs to aggravate ferroptosis. Our results showed that RSL-3- and CT20p-loaded RMPs (RC@RMPs) led to ferroptosis and apoptosis of RM-1 cells. Moreover, CT20p had a synergistic effect on ferroptosis by promoting reactive oxygen species (ROS) production, lipid hydroperoxide production, and mitochondrial instability. RC@RMPs elevated dendritic cell (DC) expression of MHCII, CD80, and CD86 and facilitated M1 macrophage polarization. In a subcutaneously transplanted RM-1 tumor model in mice, RC@RMPs inhibited tumor growth and prolonged survival time via DC activation, macrophage reprogramming, enhancement of CD8+ T cell infiltration, and proinflammatory cytokine production in the tumor. Moreover, combination treatment with anti-PD-1 improved RM-1 tumor inhibition. This study provides a strategy for the synergistic enhancement of ferroptosis for prostate cancer immunotherapies.
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Micropartículas Derivadas de Células , Ferroptose , Neoplasias da Próstata , Espécies Reativas de Oxigênio , Microambiente Tumoral , Ferroptose/efeitos dos fármacos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Animais , Camundongos , Micropartículas Derivadas de Células/metabolismo , Linhagem Celular Tumoral , Humanos , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Camundongos Endogâmicos C57BLRESUMO
Diabetic retinopathy (DR) is one of the common diabetic microangiopathies, which severely impairs vision in diabetic population. The underlying mechanisms regarding the development of DR are not fully understood, and there is a lack of biomarkers to guide clinical, assessment of disease progression. Recently researchers have found that microparticles (MP) and its bioactive molecules are involved in the development of DR. MP is widely distributed in the circulation and can exert autocrine and paracrine benefits in intercellular signalling, provide a catalytic platform for the thrombospondin complex to promote coagulation, and promote the accumulation of reactive oxygen species to cause endothelial damage. MP interacts with advanced glycosylation end products (AGE) and AGE receptor (RAGE) to activate inflammatory pathways. MP carries a variety of miRNAs that regulate the vascular endothelial growth factor generation pathway. MP has also been applied to the exploration of mesenchymal stromal cell replacement therapy to treat DR. In a word, MP provides new ideas for the study of DR. MP has emerged as a marker to assess the progression of DR. As a potential therapeutic target, MP also has considerable research value.
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Biomarcadores , Micropartículas Derivadas de Células , Retinopatia Diabética , Humanos , Retinopatia Diabética/terapia , Micropartículas Derivadas de Células/metabolismo , Biomarcadores/metabolismo , Progressão da Doença , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
For taste masking of fexofenadine hydrochloride (FXD), ethylcellulose (EC) microparticles with FXD were developed. The amounts of EC, Tween 80, and polyvinyl alcohol (PVA) in the composition had little effect on initial drug release properties. Based on the results of the drug recovery and the drug release properties, FXD(EC200) was the optimal FXD microparticle formulation. From the results of Fourier transform infrared spectroscopy spectra and X-ray diffraction patterns of FXD(EC200), FXD amorphization in the microparticles and interaction between FXD and other components were suggested, and the formation of a solid dispersion of FXD was suggested. Because the possibility of the complex of PVA and FXD on the particle surface was suggested, sodium lauryl sulfate (SLS) was added to the composition. The initial drug release from FXD microparticles with SLS was further suppressed compared with FXD(EC200). From these results, FXD microparticles with SLS can be prepared as a controlled-release formulation and are expected to be useful for masking the bitter tasting particulates.
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Paladar , Terfenadina , Terfenadina/farmacologia , Celulose/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tamanho da Partícula , SolubilidadeRESUMO
Laser-induced breakdown spectroscopy (LIBS) is a promising technique for the readout of immunochemical assays utilizing indirect detection of labels (Tag-LIBS), typically based on nanoparticles. We have previously demonstrated that Tag-LIBS immunoassay employing yttrium-based photon-upconversion nanoparticles (UCNPs) can reach sensitivity similar to commonly used enzyme and fluorescence immunoassays. In this study, we report on further increasing the sensitivity of UCNP-based Tag-LIBS immunoassay by employing magnetic microbeads (MBs) as the solid phase in the determination of cancer biomarker prostate-specific antigen. Due to the possibility of analyte preconcentration, MBs enabled achieving a limit of detection (LOD) of 4.0 pg·mL-1, representing two orders of magnitude improvement compared with equivalent microtiter plate-based assay (LOD of 460 pg·mL-1). In addition, utilizing MBs opens up the possibility of an internal standardization of the LIBS readout by employing iron spectral lines, which improves the assay robustness by compensating for LIBS signal fluctuations and bead-bound immunocomplexes lost throughout the washing steps. Finally, the practical applicability of the technique was confirmed by the successful analysis of clinical samples, showing a strong correlation with the standard electrochemiluminescence immunoassay. Overall, MB-based Tag-LIBS was confirmed as a promising immunoassay approach, combining fast readout, multiplexing possibilities, and high sensitivity approaching upconversion luminescence scanning while avoiding the requirement of luminescence properties of labels.
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Lasers , Limite de Detecção , Antígeno Prostático Específico , Antígeno Prostático Específico/análise , Antígeno Prostático Específico/imunologia , Antígeno Prostático Específico/sangue , Humanos , Imunoensaio/métodos , Análise Espectral/métodos , Ítrio/química , Ítrio/efeitos da radiação , Masculino , MicroesferasRESUMO
Streptomyces produce a broad spectrum of biologically active molecules such as oxytetracycline and rimocidin, which are widely used in human and animal treatments. microparticle-enhanced cultivation (MPEC) is one of the tools used for Streptomyces bioprocesses intensification by the control of mycelial morphology. In the present work, morphological changes of Streptomyces rimosus caused by the addition of 10 µm talc microparticles in MPEC were correlated with the biosynthetic activity of the microorganism. Comparing the runs with and without microparticles, major morphological changes were observed in MPEC, including the deformation of pellets, variation of their size, appearance of hyphae and clumps as well as the aggregation of mycelial objects. The presence of talc microparticles also influenced the levels of the studied secondary metabolites produced by S. rimosus. Comparing control and MPEC runs, the addition of talc microparticles increased the amounts of oxytetracycline (9-fold), 2-acetyl-2-decarboxamido-oxytetracycline (7-fold), milbemycin A3+4[O] (3-fold) and CE 108 (1.5-fold), while rimocidin (27-ethyl) and milbemycin ß11+4[O] production was reduced. In summary, the addition of talc microparticles to S. rimosus cultivations led to the development of smaller morphological forms like hyphae and clumps as well as to the changes in the amounts of secondary metabolites.
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Streptomyces rimosus , Streptomyces rimosus/metabolismo , Streptomyces rimosus/crescimento & desenvolvimento , Talco/química , Oxitetraciclina/biossínteseRESUMO
This study aims to investigate Polylactic Acid (PLA) and Polycaprolactone (PCL) polymers for microencapsulation of hydrophilic and hydrophobic anti-glaucoma drugs using an emulsion-based solvent evaporation technique. Microparticle size was analysed using optical microscopy, while drug-polymer interactions through Dynamic-Light-Scattering (DLS) and Fourier-Transform-Infra-red/Attenuated-Total-Reflection spectroscopy (FTIR/ATR). In vitro, drug release studies were performed to investigate drug encapsulation and release profiles. Spherical microparticles, with particle size 94 ± 6.9 µm for PCL-based and 100 ± 3.74 µm for PLA-based formulation, were obtained. Drug release studies showed 100% release over about 32 days, with encapsulation efficiency (%EE) and drug loading (%w/w) reaching up to 95 and 2.84% for PLA-based and 97 and 2.91% for PCL-based microparticles, respectively. DLS studies reveal an increase in hydrodynamic radius (RH), which correlates to enhanced drug encapsulation. So, the nature of the drug and polymer significantly impacts drug encapsulation and release, with drug-polymer interactions playing a crucial role alongside experimental parameters.
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Background and Objectives: An extracellular vesicle is part of a class of submicron particles derived from cells, mediating cellular crosstalk through microRNA (miRNA). MiRNA is a group of RNA molecules, each of which consists of 15-22 nucleotides and post-transcriptionally modulates gene expression. The complementary mRNAs-onto which the miRNAs hybridize-are involved in processes such as implantation, tumor suppression, proliferation, angiogenesis, and metastasis that define the entire tumor microenvironment. The endometrial biopsy is a standard technique used to recognize cellular atypia, but other non-invasive markers may reduce patient discomfort during the use of invasive methods. The present study aims to examine the distribution and the regulation of the differentially expressed miRNAs (DEMs) and EV-derived substances in women with endometrial cancer. Materials and Methods: We systematically searched the PubMed, EMBASE, Scopus, Cochrane Library, and ScienceDirect databases in April 2023, adopted the string "Endometrial Neoplasms AND Exosomes", and followed the recommendations in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We selected all the studies that included patients with endometrial cancer and that described the regulation of miRNA molecules in that context. The differences in molecule expression between patients and controls were evaluated as significant when the proteins had a fold change of ±1.5. Results: Seventeen records fulfilled the inclusion criteria: a total of 371 patients and 273 controls were analyzed. The upregulated molecules that had the widest delta between endometrial cancer patients and controls-relative expression ≥ 1 > 3 log2(ratio)-were miR-20b-5p, miR-204-5p, miR-15a-5p, and miR-320a. In particular, miR-20b-5p and miR-204-5p were extracted from both serum and endometrial specimens, whereas miR-15a-5p was only isolated from plasma, and miR-320a was only extracted from the endometrial specimens. In parallel, the most downregulated miRNA in the endometrial cancer patients compared to the healthy subjects was miR-320a, which was found in the endometrial specimens. Conclusions: Although their epigenetic regulation remains unknown, these upregulated molecules derived from EVs are feasible markers for the early detection of endometrial cancer. The modulation of these miRNA molecules should be assessed during different treatments or if recurrence develops in response to a targeted treatment modality.
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Neoplasias do Endométrio , MicroRNAs , Feminino , Humanos , Implantação do Embrião , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/terapia , Endométrio/patologia , Epigênese Genética , MicroRNAs/genética , Microambiente TumoralRESUMO
Thrombomodulin (TM) is a type I transmembrane glycoprotein mainly expressed on the endothelial cells, where it binds thrombin to form the thrombin-TM complex that can activate protein C and thrombin-activable fibrinolysis inhibitor (TAFI) and induce anticoagulant and anti-fibrinolytic reactions, respectively. Cell activation and injury often sheds microparticles that contain membrane TM, which circulate in biofluids like blood. However, the biological function of circulating microparticle-TM is still unknown even though it has been recognized as a biomarker of endothelial cell injury and damage. In comparison with cell membrane, different phospholipids are exposed on the microparticle surface due to cell membrane ''flip-flop'' upon cell activation and injury. Liposomes can be used as a microparticle mimetics. In this report, we prepared TM-containing liposomes with different phospholipids as surrogates of endothelial microparticle-TM and investigated their cofactor activities. We found that liposomal TM with phosphatidylethanolamine (PtEtn) showed increased protein C activation but decreased TAFI activation in comparison to liposomal TM with phosphatidylcholine (PtCho). In addition, we investigated whether protein C and TAFI compete for the thrombin/TM complex on the liposomes. We found that protein C and TAFI did not compete for the thrombin/TM complex on the liposomes with PtCho alone and with low concentration (5%) of PtEtn and phosphatidylserine (PtSer), but competed each other on the liposomes with higher concentration (10%) of PtEtn and PtSer. These results indicate that membrane lipids affect protein C and TAFI activation and microparticle-TM may have different cofactor activities in comparison to cell membrane TM.