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1.
Biomaterials ; 305: 122456, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38184961

RESUMO

Combination therapy based on sonodynamic therapy (SDT) combined with immune checkpoint blockers anti-PD-L1 provides effective anti-tumor effects. We designed a combination therapy based on M1/PLGA@IR780/CAT NPs of SDT-enhanced immunity combined with immune checkpoint blockers against PD-L1, which was based on M1 macrophage membrane-encapsulated poly (lactic-co-glycolic acid) (PLGA) nanoparticles loaded with the acoustic sensitizer IR780 and catalase (CAT) to successfully realize it. SDT based on M1/PLGA@IR780/CAT NPs could induce tumor cell death by promoting dendritic cell (DC) maturation and modulating the tumor immune microenvironment. In particular, the systemic anti-tumor immune response and potent immune memory induced upon combination with anti-PD-L1 checkpoint blockade not only alleviated the progression of mammary cancer in 4T1 mice and effectively blocked distant metastasis, but also prevented tumor recurrence, providing a promising new therapeutic strategy for clinical tumor therapy.


Assuntos
Inibidores de Checkpoint Imunológico , Nanopartículas , Animais , Camundongos , Biomimética , Recidiva Local de Neoplasia , Imunoterapia , Macrófagos , Linhagem Celular Tumoral , Microambiente Tumoral
2.
Small ; 20(7): e2303506, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37806770

RESUMO

Aseptic loosening of prostheses is a highly researched topic, and wear particle-induced macrophage polarization is a significant cause of peri-prosthetic osteolysis. Exosomes derived from bone marrow mesenchymal stem cells (BMSCs-Exos) promote M2 polarization and inhibit M1 polarization of macrophages. However, clinical application problems such as easy clearance and lack of targeting exist. Exosomes derived from M2 macrophages (M2-Exos) have good biocompatibility, immune escape ability, and natural inflammatory targeting ability. M2-Exos and BMSCs-Exos fused exosomes (M2-BMSCs-Exos) are constructed, which targeted the osteolysis site and exerted the therapeutic effect of both exosomes. M2-BMSCs-Exos achieved targeted osteolysis after intravenous administration inhibiting M1 polarization and promoting M2 polarization to a greater extent at the targeted site, ultimately playing a key role in the prevention and treatment of aseptic loosening of prostheses. In conclusion, M2-BMSCs-Exos can be used as a precise and reliable molecular drug for peri-prosthetic osteolysis. Fused exosomes M2-BMSCs-Exos  were originally proposed and successfully prepared, and exosome fusion technology provides a new theoretical basis and solution for the clinical application of therapeutic exosomes.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Osteólise , Humanos , Administração Intravenosa , Macrófagos
3.
J Nanobiotechnology ; 21(1): 398, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37904168

RESUMO

The wear particle-induced dissolution of bone around implants is a significant pathological factor in aseptic loosening, and controlling prosthetic aseptic loosening holds crucial social significance. While human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exos, Exos) have been found to effectively promote osteogenesis and angiogenesis, their role in periprosthetic osteolysis remains unexplored. To enhance their in vivo application, we engineered HucMSCs-Exos-encapsulated poly lactic-co-glycolic acid (PLGA) nanoparticles (PLGA-Exos). In our study, we demonstrate that PLGA-Exos stimulate osteogenic differentiation while inhibiting the generation of reactive oxygen species (ROS) and subsequent osteoclast differentiation in vitro. In vivo imaging revealed that PLGA-Exos released exosomes slowly and maintained a therapeutic concentration. Our in vivo experiments demonstrated that PLGA-Exos effectively suppressed osteolysis induced by polyethylene particles. These findings suggest that PLGA-Exos hold potential as a therapeutic approach for the prevention and treatment of periprosthetic osteolysis. Furthermore, they provide novel insights for the clinical management of osteolysis.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Nanopartículas , Osteólise , Humanos , Osteogênese , Osteólise/induzido quimicamente , Osteólise/terapia , Polietileno/efeitos adversos , Glicóis/efeitos adversos , Cordão Umbilical
4.
Arthroscopy ; 39(12): 2529-2546.e1, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37683831

RESUMO

PURPOSE: To investigate whether tranexamic acid (TXA) is cytotoxic in chondrocyte and cartilage tissues, as well as explore the mechanisms behind the possible toxicity in detail. METHODS: We detected the cell viability of chondrocytes in vitro and the change of morphology and specific in vivo contents of cartilage after TXA treatment. Furthermore, we detected apoptosis in cartilage. We used apoptosis-specific staining, reactive oxygen species detection, mitochondrial membrane potential detection, flow cytometry, and western blot for apoptosis detection. Finally, we detected the activation of endoplasmic reticulum stress (ERS) in TXA-treated chondrocytes to clarify the mechanism behind chondrocyte apoptosis. RESULTS: TXA presented an increasing toxic effect with increasing concentrations, especially in the 100 mg/mL group. In addition, we found that 50 mg/mL and 100 mg/mL TXA significantly increased apoptosis in cartilage and subchondral bone. TXA could induce chondrocyte apoptosis in cell and protein levels with reactive oxygen species generation and mitochondrial membrane depolarization. An apoptosis inhibitor could inhibit the induced apoptosis. Next, TXA induced calcium overload in chondrocytes and increased ERS-specific protein expression, whereas ERS inhibitor blocked ERS activation and further inhibited chondrocyte apoptosis. CONCLUSIONS: We concluded that TXA had a toxic effect on chondrocytes by inducing apoptosis through ERS activation, especially in 50 mg/mL and 100 mg/mL groups. We recommend TXA concentrations of less than 50 mg/mL in joint surgeries. CLINICAL RELEVANCE: It is still unclear whether TXA has a toxic effect on cartilage when topically used in joint surgeries. The concentration also varies. This study provides additional evidence that TXA at high concentrations will cause cartilage damage, which will help to provide a new understanding of the clinical administration of TXA.


Assuntos
Condrócitos , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/farmacologia , Espécies Reativas de Oxigênio , Apoptose , Estresse do Retículo Endoplasmático
5.
Front Immunol ; 14: 1120034, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845112

RESUMO

PANoptosis, a new research hotspot at the moment, is a cell death pattern in which pyroptosis, apoptosis, and necroptosis all occur in the same cell population. In essence, PANoptosis is a highly coordinated and dynamically balanced programmed inflammatory cell death pathway that combines the main features of pyroptosis, apoptosis, and necroptosis. Many variables, such as infection, injury, or self-defect, may be involved in the occurrence of PANoptosis, with the assembly and activation of the PANoptosome being the most critical. PANoptosis has been linked to the development of multiple systemic diseases in the human body, including infectious diseases, cancer, neurodegenerative diseases, and inflammatory diseases. Therefore, it is necessary to clarify the process of occurrence, the regulatory mechanism of PANoptosis, and its relation to diseases. In this paper, we summarized the differences and relations between PANoptosis and the three types of programmed cell death, and emphatically expounded molecular mechanism and regulatory patterns of PANoptosis, with the expectation of facilitating the application of PANoptosis regulation in disease treatment.


Assuntos
Apoptose , Doenças Neurodegenerativas , Humanos , Apoptose/fisiologia , Piroptose , Morte Celular , Necroptose , Doenças Neurodegenerativas/terapia
6.
Mater Today Bio ; 19: 100569, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36846309

RESUMO

The key to critical bone regeneration in tissue engineering relies on an ideal bio-scaffold coated with a controlled release of growth factors. Gelatin methacrylate (GelMA) and Hyaluronic acid methacrylate (HAMA) have been a novel topic of interest in bone regeneration while introducing appropriate nano-hydroxyapatite (nHAP) to improve its mechanical properties. And the exosomes derived from human urine-derived stem cells (human USCEXOs) have also been reported to promote osteogenesis in tissue engineering. The present study aimed to design a new GelMA-HAMA/nHAP composite hydrogel as a drug delivery system. The USCEXOs were encapsulated and slow-released in the hydrogel for better osteogenesis. The characterization of the GelMA-based hydrogel showed excellent controlled release performance and appropriate mechanical properties. The in vitro studies showed that the USCEXOs/GelMA-HAMA/nHAP composite hydrogel could promote the osteogenesis of bone marrow mesenchymal stem cells (BMSCs) and the angiogenesis of endothelial progenitor cells (EPCs), respectively. Meanwhile, the in vivo results confirmed that this composite hydrogel could significantly promote the defect repair of cranial bone in the rat model. In addition, we also found that USCEXOs/GelMA-HAMA/nHAP composite hydrogel can promote the formation of H-type vessels in the bone regeneration area, enhancing the therapeutic effect. In conclusion, our findings suggested that this controllable and biocompatible USCEXOs/GelMA-HAMA/nHAP composite hydrogel may effectively promote bone regeneration by coupling osteogenesis and angiogenesis.

7.
Acta Biomater ; 160: 297-310, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773884

RESUMO

Aseptic loosening of the prosthesis is a severe complication after joint replacement. It is of great practical significance and social value to discover the prevention and treatment strategies for this condition. Exosomes from urine-derived stem cells (Exos) have great potential in promoting bone repair, reconstruction, and regulating bone metabolism. However, they are easily eliminated by macrophages and incapable of targeting the osteolysis zone. In this study, based on macrophage "homing" into periprosthetic osteolysis region and cell membrane encapsulating nanotechnology, exosomes from urine-derived stem cells were encapsulated with macrophage membrane (MM) to prevent periprosthetic osteolysis. We found that macrophage membrane encapsulated urine-derived stem cell-derived exosomes (MM-Exos) can be targeted delivery to the osteolysis zone and enhance the therapeutic effectiveness of Exos, which alleviated wear particles-induced calvarial osteolysis. Furthermore, MM-Exos could provide immunological camouflage and allow the Exos to avoid phagocytosis by macrophages and stimulate cellular uptake by bone marrow-derived stem cells (BMSCs). Therefore, we demonstrated the unique ability of the macrophage membrane as a targeted transport of exosomes from urine-derived stem cells for the prevention and treatment of periprosthetic osteolysis. These biomimetic nanoparticles provided a new therapeutic exosome delivery system for preventing wear particles-induced osteolysis. STATEMENT OF SIGNIFICANCE: Macrophage membrane encapsulated urine-derived stem cell-derived exosomes (MM-Exos) can be targeted delivery to the osteolysis zone and enhance the therapeutic effect of Exos on peri­prosthetic osteolysis prevention. MM-Exos could allow the Exos to avoid phagocytosis by macrophages and promote the uptake of Exos by BMSCs.


Assuntos
Exossomos , Osteólise , Humanos , Osteólise/induzido quimicamente , Células-Tronco , Exossomos/metabolismo , Membrana Celular , Macrófagos
8.
Am J Med Sci ; 365(4): 396-400, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36535540

RESUMO

Differentiating the type and cause of shock is crucial for intensive care. The rapid aggravation of lactic acidosis in patients often indicates a severe impairment of oxygen uptake in tissues. Herein, we presented a rare case of refractory distributive shock with severe wet beriberi. A 40-year-old male was admitted to the emergency department (ED) with recurrent chest tightness and lower extremity edema. The condition of the patient continued to deteriorate after symptomatic treatments. After several turnovers, the medical history of the patient was requested again and finally obtained. Our emergency management team hypothesized that the thiamine-deficient diet caused an aerobic metabolism disorder in the patient. Overall, we aimed to alert clinicians to unusual causes of distributive shock and further discussed the application of thiamine supplementary therapy in critical care.


Assuntos
Beriberi , Choque , Deficiência de Tiamina , Masculino , Humanos , Adulto , Beriberi/complicações , Beriberi/tratamento farmacológico , Tiamina/uso terapêutico , Choque/tratamento farmacológico , Choque/etiologia
9.
Front Endocrinol (Lausanne) ; 13: 891313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909545

RESUMO

Osteoporosis is a bone metabolic disorder characterized by decreased bone density and deteriorated microstructure, which increases the risk of fractures. The imbalance between bone formation and bone resorption results in the occurrence and progression of osteoporosis. Osteoblast-mediated bone formation, osteoclast-mediated bone resorption and macrophage-regulated inflammatory response play a central role in the process of bone remodeling, which together maintain the balance of the osteoblast-osteoclast-macrophage (OB-OC-MΦ) axis under physiological conditions. Bone formation and bone resorption disorders caused by the imbalance of OB-OC-MΦ axis contribute to osteoporosis. Many microRNAs are involved in the regulation of OB-OC-MΦ axis homeostasis, with microRNA-23a (miR-23a) being particularly crucial. MiR-23a is highly expressed in the pathological process of osteoporosis, which eventually leads to the occurrence and further progression of osteoporosis by inhibiting osteogenesis, promoting bone resorption and inflammatory polarization of macrophages. This review focuses on the role and mechanism of miR-23a in regulating the OB-OC-MΦ axis to provide new clinical strategies for the prevention and treatment of osteoporosis.


Assuntos
Reabsorção Óssea , MicroRNAs , Osteoporose , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Humanos , Macrófagos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/etiologia , Osteoporose/genética , Osteoporose/fisiopatologia , Osteoporose/terapia
10.
Life Sci ; 307: 120868, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940216

RESUMO

Ferroptosis is a kind of iron-dependent regulatory necrosis characterized by the fatal accumulation of iron-dependent lipid peroxides in the plasma membrane and the final oxidative damage of the cell membrane. Morphologically, ferroptosis features high membrane density, decreased or disappeared cristae, rupture of the mitochondrial outer membrane, plasma membrane integrity loss, cytoplasmic swelling, and organelle swelling. Under physiological conditions, ferroptosis occurs through two major pathways, the extrinsic or transporter-dependent pathway and the intrinsic or enzyme-regulated pathway, triggered by a series of small molecules inside and outside the cell. At present, it is assumed that ferroptosis is mainly related to abnormal toxicity of iron, lipid peroxidation, and mitochondrial dysfunction. With more detailed studies, ferroptosis plays potential pathogenic roles in multisystem diseases as a pathological response, and targeted regulation of ferroptosis in treating ferroptosis-related diseases has broad prospects. In conclusion, it is of great clinical significance to further clarify the specific mechanism of ferroptosis and explore new strategies for ferroptosis regulation. The present review emphatically summarizes the latest mechanism of ferroptosis, focusing on the regulation mechanism and clinical application of ferroptosis inducers and inhibitors. We are devoted to providing new ideas for the further study of ferroptosis and the diagnosis and treatment of ferroptosis-related multisystem diseases.


Assuntos
Ferroptose , Ferro/metabolismo , Peroxidação de Lipídeos , Peróxidos Lipídicos , Estresse Oxidativo
11.
Front Bioeng Biotechnol ; 10: 925841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032702

RESUMO

Periprosthetic osteolysis is a major long-term complication of total joint replacement. A series of biological reactions caused by the interaction of wear particles at the prosthesis bone interface and surrounding bone tissue cells after artificial joint replacement are vital reasons for aseptic loosening. Disorder of bone metabolism and aseptic inflammation induced by wear particles are involved in the occurrence and development of aseptic loosening of the prosthesis. Promoting osteogenesis and angiogenesis and mediating osteoclasts and inflammation may be beneficial in preventing the aseptic loosening of the prosthesis. Current research about the prevention and treatment of aseptic loosening of the prosthesis focuses on drug, gene, and stem cell therapy and has not yet achieved satisfactory clinical efficacy or has not been used in clinical practice. Exosomes are a kind of typical extracellular vehicle. In recent years, stem cell exosomes (Exos) have been widely used to regulate bone metabolism, block inflammation, and have broad application prospects in tissue repair and cell therapy.

12.
Cancer Gene Ther ; 29(11): 1542-1549, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35764712

RESUMO

The homeobox gene family encodes transcription factors that are essential for cell growth, proliferation, and differentiation, and its dysfunction is linked to tumor initiation and progression. Sine oculis homeobox (SIX) belongs to the homeobox gene family, with SIX3 being a core member. Recent studies indicate that SXI3 functions as a cancer suppressor or promoter, which is mainly dependent on SIX3's influence on the signal pathways that promote or inhibit cancer in cells. The low expression of SIX3 in most malignant tumors was confirmed by detailed studies, which could promote the cell cycle, proliferation, migration, and angiogenesis. The recovery or upregulation of SIX3 expression to suppress cancer is closely related to the direct or indirect inhibition of the Wnt pathway. However, in some malignancies, such as esophageal cancer and gastric cancer, SIX3 is a tumor-promoting factor, and repressing SIX3 improves patients' prognosis. This review introduces the research progress of SIX3 in tumors and gives a comprehensive analysis, intending to explain why SIX3 plays different roles in different cancers and provide new cancer therapy strategies.


Assuntos
Proteínas de Homeodomínio , Neoplasias , Humanos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Regiões Promotoras Genéticas , Neoplasias/genética , Neoplasias/terapia
13.
Life Sci ; 301: 120602, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35508253

RESUMO

Megakaryocytes (MKs) are typical cellular components in the circulating blood flowing from the heart into the lungs. Physiologically, MKs function as an important regulator of platelet production and immunoregulation. However, dysfunction in MKs is considered a trigger in various diseases. It has been described that the lung is an important site of platelet biogenesis from extramedullary MKs, which may play an essential role in various pulmonary diseases. With detailed studies, there are different degrees of numerical changes of MKs in coronavirus disease 2019 (COVID-19), acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), lung cancer, pulmonary fibrosis (PF), and other pulmonary diseases. Also, MKs inhibit or promote the development of pulmonary diseases through various pathways. Here, we summarize the current knowledge of MKs in pulmonary diseases, highlighting the physiological functions and integrated molecular mechanisms. We aim to shine new light on not only the subsequent study of MKs but also the diagnosis and treatment of pulmonary diseases.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Plaquetas , Humanos , Pulmão , Megacariócitos , Trombopoese
14.
Oxid Med Cell Longev ; 2021: 1098970, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630843

RESUMO

Ferroptosis is an iron-dependent regulated necrosis characterized by the peroxidation damage of lipid molecular containing unsaturated fatty acid long chain on the cell membrane or organelle membrane after cellular deactivation restitution system, resulting in the cell membrane rupture. Ferroptosis is biochemically and morphologically distinct and disparate from other forms of regulated cell death. Recently, mounting studies have investigated the mechanism of ferroptosis, and numerous proteins play vital roles in regulating ferroptosis. With detailed studies, emerging evidence indicates that ferroptosis is found in multiple lung diseases, demonstrating that ferroptosis appears to be particularly important for lung diseases. The mounting interest in ferroptosis drugs specifically targeting the ferroptosis mechanism holds substantial therapeutic promise in lung diseases. The present review emphatically summarizes the functions and integrated molecular mechanisms of ferroptosis in various lung diseases, proposing that multiangle regulation of ferroptosis might be a promising strategy for the clinical treatment of lung diseases.


Assuntos
Ferroptose/efeitos dos fármacos , Pneumopatias/tratamento farmacológico , Pneumopatias/metabolismo , Terapia de Alvo Molecular/métodos , Animais , Autofagia , Humanos , Ferro/metabolismo , Peroxidação de Lipídeos , Necrose , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Resultado do Tratamento
15.
Life Sci ; 275: 119364, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33741415

RESUMO

ß-arrestin2 is a ubiquitously expressed scaffold protein localized on the cytoplasm and plasma membrane. It was originally found to bind to GPCRs, uncoupling G proteins and receptors' binding and inhibiting the signal transduction of the GPCRs. Further investigations have revealed that ß-arrestin2 not only mediates the desensitization of GPCRs but also serves as a multifunctional scaffold to mediate receptor internalization, kinase activation, and regulation of various signaling pathways, such as TLR4/NF-κB, MAPK, Wnt, TGF-ß, and AMPK/mTOR pathways. ß-arrestin2 regulates cell invasion, migration, autophagy, angiogenesis, and anti-inflammatory effects by regulating various signaling pathways, which play a vital role in many physiological and pathological processes. This paper reviews the structure and function of ß-arrestin2, the regulation of ß-arrestin2 based signaling pathways. The role and mechanism of ß-arrestin2 signaling have been delineated in sufficient detail. The prospect of regulating the expression and activity of ß-arrestin2 in multisystem diseases holds substantial therapeutic promise.


Assuntos
Transdução de Sinais , beta-Arrestina 2/metabolismo , Animais , Humanos , beta-Arrestina 2/fisiologia
16.
Chem Sci ; 7(3): 2138-2144, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29899941

RESUMO

Ion-exchange materials, currently dominated by resins, are widely used in a plethora of areas. However, the drawbacks of conventional resins necessitate the creation of a new model of ion exchange materials that feature controllable swelling, easily accessible ion exchange sites, high ion exchange capacity, fast ion exchange kinetics, and high chemical stability as illustrated herein in the context of functionalizing a porous organic polymer (POP) with ion exchange groups. The advantages of POP-based ion exchange materials in comparison with conventional resins and other types of ion exchange materials have been highlighted through an evaluation of their performances in scavenging precious metals at trace concentrations, removal of nuclear waste model ions, and size-selective ion capture. Our work thereby provides a new perspective to develop ion functionalized POPs as a versatile type of ion exchange materials for various applications.

17.
J Am Chem Soc ; 136(4): 1202-5, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24428188

RESUMO

In this work, a new strategy is developed to encapsulate a metal-functionalized guest molecule into a metal-organic framework (MOF) via metal-cation-directed de novo assembly from the component fragments of the guest molecule. This strategy, as illustrated in proof-of-principle studies on the de novo assembly of metal(II) phthalocyanine molecules into bio-MOF-1, can circumvent some drawbacks of existing approaches for encapsulating guest molecules into MOFs, such as inaccessibility for larger guest molecules due to limitations of the MOF window size and disruption of the MOF framework structure by functionalized guest molecules. Overall, this work provides a general yet versatile approach for encapsulating a broader range of metal-functionalized guest molecules into MOFs for various applications.

18.
Chem Commun (Camb) ; 48(64): 7946-8, 2012 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-22760593

RESUMO

Metal-organic polyhedra (MOP) nanocages were successfully surface functionalized via ionic self-assembly and the ordered honeycomb architecture of the encapsulated MOP nanocages was also fabricated at the air/water surface. The results provide a novel synthetic method and membrane processing technique of amphiphilic MOP nanocages for various applications.


Assuntos
Nanoestruturas/química , Compostos Organometálicos/síntese química , Ar , Íons/química , Modelos Moleculares , Compostos Organometálicos/química , Tamanho da Partícula , Propriedades de Superfície , Água/química
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