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1.
Vox Sang ; 118(8): 637-646, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37278100

RESUMEN

BACKGROUND AND OBJECTIVES: Umbilical cord blood (UCB) has been used as a source of red blood cells (RBCs) for neonatal/paediatric transfusion purposes. This study adopted two different procedures to obtain umbilical RBC (U-RBC) to compare its quality control parameters to those of fractionated adult RBC (A-RBC), for paediatric purposes. MATERIALS AND METHODS: UCB units (24) were filtered and processed based on two different methods, namely, conventional/manual (P1;n12) and automatic (P2;n12). They were compared to five fractionated A-RBCs. U-RBC and A-RBC were stored for 14 days and had their haematological, biochemical, haemolytic and microbiological parameters analysed at D1, D7 and D14. Cytokines and growth factors (GFs) in residual U-RBC plasma were measured. RESULTS: Mean volume of processed U-RBC units was 45 mL for P1 and 39 mL for P2; the mean haematocrit level reached 57% for P1 and 59% for P2. A-RBC recorded a mean volume of 44 mL. Haematologic and biochemical parameters analysed in U-RBC and A-RBC presented similar behaviours during storage time, except for parameter values, which differed between them. Pro-inflammatory and immunomodulatory cytokines, as well as GFs, were higher in U-RBC residual plasma than in that A-RBC. CONCLUSION: UCB can be processed into RBC based on either manual or automated protocols. U-RBC units met the referenced quality parameters defined for A-RBC. Some features, mainly the biochemical ones, should be further investigated to help improve quality parameters, with emphasis on differences found in, and particularities of, this material and on recipients of this new transfusion practice.


Asunto(s)
Eritrocitos , Sangre Fetal , Humanos , Recién Nacido , Conservación de la Sangre/métodos , Transfusión Sanguínea/métodos , Citocinas , Niño
2.
Nanomedicine ; 41: 102531, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35114406

RESUMEN

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory and autoimmune disease whose biomarker is the anti-AQP4-IgG autoantibody that binds to aquaporin-4 (AQP4) protein. We introduced a nanosensor with a sensitivity of 84.6%, higher than the CBA's 76.5%. Using silver nanoparticles (AgNPs), we detected not only seropositive but also some false-negative patients previously classified with CBA. It consisted of AgNPs coated with one of a panel of 5 AQP4 epitopes. The ability in detecting the anti-AQP4-IgG in NMOSD patients depended on the epitope and synergy could be obtained by combining different epitopes. We demonstrated that NMOSD patients could easily be distinguished from healthy subjects and patients with multiple sclerosis. Using the most sensitive AQP461-70 peptide, we established a calibration curve to estimate the concentration of anti-AQP4-IgG in seropositive NMOSD patients. The ability to enhance the accuracy of the diagnosis may improve the prognosis of 10-27% of anti-AQP4-IgG seronegative patients worldwide.


Asunto(s)
Nanopartículas del Metal , Neuromielitis Óptica , Acuaporina 4 , Colorimetría , Humanos , Inmunoglobulina G , Neuromielitis Óptica/diagnóstico , Plata
3.
Environ Toxicol ; 37(9): 2314-2323, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35661558

RESUMEN

The possibility of chemical contamination is an important issue to consider when designing a cell therapy strategy. Both bisphenol A (BPA) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are among the most environmentally relevant endocrine disrupting chemicals (EDCs, compounds with a high affinity for adipose tissue) recently studied. Adipose-derived stem cells (ASCs) are mesenchymal stromal cells (MSCs) obtained from adipose tissue widely used in regenerative medicine to prevent and treat diseases in several tissues and organs. Although the experimental use of tissue-engineered constructs requires careful analysis for approval and implantation, there has been a recent increase in the number of approved clinical trials for this promising strategy. This study aimed to evaluate cell viability, apoptosis, DNA damage, and the adipogenic or osteogenic differentiation potential of rat adipose-derived stem cells (rASCs) exposed to previously established non-cytotoxic doses of BPA and TCDD in vitro. Results demonstrated that 10 µM of BPA and 10 nM of TCDD were able to significantly reduce cell viability, while all exposure levels resulted in DNA damage, although did not increase the apoptosis rate. According to the analysis of adipogenic differentiation, 1 µM of BPA induced the significant formation of oil droplets, suggesting an increased adipocyte differentiation, while both 10 µM of BPA and 10 nM of TCDD decreased adipocyte differentiation. Osteogenic differentiation did not differ among the treatments. As such, BPA and TCDD in the concentrations tested can modify important processes in rASCs such as cell viability, adipogenic differentiation, and DNA damage. Together, these findings prove that EDCs play an important role as contaminants, putatively interfering in cell differentiation and thus impairing the therapeutic use of ASCs.


Asunto(s)
Dibenzodioxinas Policloradas , Adipocitos , Tejido Adiposo , Animales , Compuestos de Bencidrilo , Diferenciación Celular , Osteogénesis , Fenoles , Dibenzodioxinas Policloradas/toxicidad , Ratas , Células Madre
4.
J Nanosci Nanotechnol ; 19(7): 3772-3776, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30764933

RESUMEN

The diagnostics of the autoimmune hemolytic anemia (AIHA), a rare disease caused by autoantibody-induced hemolysis, is still prone to false positives for it is based on visual observation in the so-called Direct Coombs test. In this study, we developed a specific IgG hemolysis immunosensor produced with layer-by-layer (LbL) films containing a monoclonal antibody against human immunoglobulin (mAbIMUG) deposited along with a layer of silk fibroin (SF) derived from Bombyx mori cocoons. Adsorption of mAbIMUG on a SF layer was confirmed by the fluorescence emission band at 326 nm. Immunosensors were prepared with LbL films deposited on interdigitated gold electrodes for impedance spectroscopy and on screen printed carbon electrodes for electrochemical measurements. When the SF/mAbIMUGLbL film was exposed to healthy red blood cells (RBCs), no cell binding was observed by the optical microscopy images. In addition, no major changes were observed in the signals of the square wave voltammogram and in the impedance spectra. In contrast, the electrochemical signal was significantly increased and the dielectric loss curve shifted for the sensing units containing RBCs with the antibody attached on the surface ("sick cells"). Furthermore, cell attachment was so strong that optical images still showed covered electrodes even after washing in PBS buffer. The detection with two distinct methods seems promising for an effective diagnosis of AIHA.


Asunto(s)
Anemia Hemolítica Autoinmune , Técnicas Biosensibles , Fibroínas , Anticuerpos Monoclonales , Humanos , Inmunoensayo
5.
J Craniofac Surg ; 28(7): 1654-1660, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28834840

RESUMEN

Reconstructive surgery to craniofacial deformities caused by tumor ressections, traumas or congenital malformation are frequent in medicine practice. It aims to provide the patients with better quality of life and functional improvement of speech, breathing, chewing, and swallowing. Many are the techniques described in the literature to recover bone defects. This study evaluated a vascularized galeal and periosteum flap in rabbits, which could possibly substitute the bone graft in reconstructive surgery, especially for facial defects. It involved rabbits, divided into 12 groups, submitted to a surgical procedure to construct the galea and periosteum cranial flap filled with fragments of cranial bone, platelet-rich plasma, mesenchimal stem cells, and hyaluronic acid. The evaluation methods included image examinations and histological analysis.The results demonstrated bone formation with the use of platelet-rich plasma, mesenchimal stem cells, and bone fragments. The use of several enrichment materials of osseous cellular stimulation improved the quality and bone tissue organization. The more enrichment factor used, the better the tissue quality result was.Much research should be done to improve the methods and to analyze if results in human have the same bone formation as it happened in rabbits.


Asunto(s)
Ácido Hialurónico/metabolismo , Células Madre Mesenquimatosas/citología , Periostio , Plasma Rico en Plaquetas/fisiología , Colgajos Quirúrgicos/cirugía , Animales , Osteogénesis , Periostio/citología , Periostio/cirugía , Conejos , Procedimientos de Cirugía Plástica
6.
J Cell Mol Med ; 20(6): 1198-200, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27012926

RESUMEN

We examined the effect of plasma incubation from preeclampsia pregnant on the antiangiogenic miR-195-5p expression. Higher miR-195-5p expression was found in cultures incubated with preeclampsia plasma compared to those incubated with healthy pregnant plasma. Next, as VEGF is a target of miR-195-5p we have quantified its expression by real-time qPCR and ELISA. We found reduced VEGF levels in culture incubated with preeclampsia plasma. Therefore, we have concluded that the higher expression of miR-195-5p in endothelial cell cultures incubated with preeclampsia plasma may contribute to decreased expression of VEGFA (gene and protein) and increased antiangiogenic status in preeclampsia. Therefore, this miR may be an important target in preeclampsia.


Asunto(s)
Inhibidores de la Angiogénesis/metabolismo , Regulación de la Expresión Génica , Células Endoteliales de la Vena Umbilical Humana/metabolismo , MicroARNs/genética , Neovascularización Fisiológica , Preeclampsia/sangre , Adulto , Femenino , Humanos , MicroARNs/metabolismo , Embarazo , Factor A de Crecimiento Endotelial Vascular/metabolismo
7.
Exp Cell Res ; 326(1): 103-11, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24929113

RESUMEN

Clinical experience for peripheral arterial disease treatment shows poor results when synthetic grafts are used to approach infrapopliteal arterial segments. However, tissue engineering may be an option to yield surrogate biocompatible neovessels. Thus, biological decellularized scaffolds could provide natural tissue architecture to use in tissue engineering, when the absence of ideal autologous veins reduces surgical options. The goal of this study was to evaluate different chemical induced decellularization protocols of the inferior vena cava of rabbits. They were decellularized with Triton X100 (TX100), sodium dodecyl sulfate (SDS) or sodium deoxycholate (DS). Afterwards, we assessed the remaining extracellular matrix (ECM) integrity, residual toxicity and the biomechanical resistance of the scaffolds. Our results showed that TX100 was not effective to remove the cells, while protocols using SDS 1% for 2h and DS 2% for 1h, efficiently removed the cells and were better characterized. These scaffolds preserved the original organization of ECM. In addition, the residual toxicity assessment did not reveal statistically significant changes while decellularized scaffolds retained the equivalent biomechanical properties when compared with the control. Our results concluded that protocols using SDS and DS were effective at obtaining decellularized scaffolds, which may be useful for blood vessel tissue engineering.


Asunto(s)
Tensoactivos/farmacología , Ingeniería de Tejidos , Andamios del Tejido , Trasplante de Tejidos , Vena Cava Inferior/citología , Vena Cava Inferior/fisiología , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Fenómenos Biomecánicos , Diferenciación Celular , Células Cultivadas , Matriz Extracelular/química , Femenino , Técnicas para Inmunoenzimas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Conejos , Vena Cava Inferior/efectos de los fármacos
8.
J Vasc Surg ; 59(6): 1677-85, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23830317

RESUMEN

BACKGROUND: Cardiovascular diseases remain leaders as the major causes of mortality in Western society. Restoration of the circulation through construction of bypass surgical treatment is regarded as the gold standard treatment of peripheral vascular diseases, and grafts are necessary for this purpose. The great saphenous vein is often not available and synthetic grafts have their limitations. Therefore, new techniques to produce alternative grafts have been developed and, in this sense, tissue engineering is a promising alternative to provide biocompatible grafts. This study objective was to reconstruct the endothelium layer of decellularized vein scaffolds, using mesenchymal stem cells (MSCs) and growth factors obtained from platelets. METHODS: Fifteen nonpregnant female adult rabbits were used for all experiments. Adipose tissue and vena cava were obtained and subjected to MSCs isolation and tissue decellularization, respectively. MSCs were subjected to differentiation using endothelial inductor growth factor (EIGF) obtained from human platelet lysates. Immunofluorescence, histological and immunohistochemical analyses were employed for the final characterization of the obtained blood vessel substitute. RESULTS: The scaffolds were successfully decellularized with sodium dodecyl sulfate. MSCs actively adhered at the scaffolds, and through stimulation with EIGF were differentiated into functional endothelial cells, secreting significantly higher quantities of von Willebrand factor (0.85 µg/mL; P < .05) than cells cultivated under the same conditions, without EIGF (0.085 µg/mL). Cells with evident morphologic characteristics of endothelium were seen at the lumen of the scaffolds. These cells also stained positive for fascin protein, which is highly expressed by differentiated endothelial cells. CONCLUSIONS: Taken together, the use of decellularized bioscaffold and subcutaneous MSCs seems to be a potential approach to obtain bioengineered blood vessels, in the presence of EIGF supplementation.


Asunto(s)
Prótesis Vascular , Células Endoteliales/citología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Procedimientos de Cirugía Plástica/métodos , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Ingeniería de Tejidos/métodos , Animales , Diferenciación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Humanos , Conejos , Andamios del Tejido
9.
Biochem Biophys Res Commun ; 430(4): 1319-21, 2013 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-23261429

RESUMEN

High-grade prostate cancers express high levels of matrix metalloproteinases (MMPs), major enzymes involved in tumor invasion and metastasis. However, the tumor cell lines commonly employed for prostate cancer research express only small amounts of MMPs when cultivated as monolayer cultures, in common culture media. The present study was conducted to ascertain whether culture conditions that include fibronectin can alter MMP2 and MMP9 expression by the human prostatic epithelial cell lines RWPE-1, LNCaP and PC-3. These cells were individually seeded at 2×10(4) cells/cm(2), cultivated until they reached 80% confluence, and then exposed for 4h to fibronectin, after which the conditioned medium was analyzed by gelatin zymography. Untreated cells were given common medium. Only RWPE-1 cells express detectable amounts of MMP9 when cultivated in common medium, whereas the addition of fibronectin induced high expression levels of pro and active forms of MMP2 in all tested cell lines. Our findings demonstrate that normal and tumor prostate cell lines express MMP2 activity when in contact with extracellular matrix components or blood plasma proteins such as fibronectin. Future studies of transcriptomes and proteomes in prostate cancer research using these cell lines should not neglect these important conclusions.


Asunto(s)
Fibronectinas/metabolismo , Metaloproteinasa 2 de la Matriz/biosíntesis , Neoplasias de la Próstata/enzimología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Fibronectinas/sangre , Fibronectinas/farmacología , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/biosíntesis , Neoplasias de la Próstata/sangre
10.
Cytotherapy ; 15(11): 1436-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23993645

RESUMEN

BACKGROUND: Platelet-rich plasma has been largely used as a therapeutic option for the treatment of chronic wounds of different etiologies. The enhanced regeneration observed after the use of platelet-rich plasma has been systematically attributed to the growth factors that are present inside platelets' granules. AIM: We hypothesize that the remaining plasma and platelet-bound fibronectin may act as a further bioactive protein in platelet-rich plasma preparations. METHODS: Recent reports were analyzed and presented as direct evidences of this hypotheses. RESULTS: Fibronectin may directly influence the extracellular matrix remodeling during wound repair. This effect is probably through matrix metalloproteinase expression, thus exerting an extra effect on chronic wound regeneration. CONCLUSIONS: Physicians should be well aware of the possible fibronectin-induced effects in their future endeavors with PRP in chronic wound treatment.


Asunto(s)
Plaquetas/metabolismo , Fibronectinas/metabolismo , Plasma Rico en Plaquetas/metabolismo , Cicatrización de Heridas/fisiología , Heridas y Lesiones/terapia , Matriz Extracelular/metabolismo , Humanos , Metaloproteinasas de la Matriz/metabolismo , Regeneración
11.
Langmuir ; 29(19): 5878-88, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23586677

RESUMEN

A new highly luminescent europium complex with the formula [Eu(TTA)3(Bpy-Si)], where TTA stands for the thenoyltrifluoroacetone, (C4H3S)COCH2COCF3, chelating ligand and Bpy-Si, Bpy-CH2NH(CH2)3Si(OEt)3, is an organosilyldipyridine ligand displaying a triethoxysilyl group as a grafting function has been synthesized and fully characterized. This bifunctional complex has been grafted onto the surface of dense silica nanoparticles (NPs) and on mesoporous silica microparticles as well. The covalent bonding of [Eu(TTA)3(Bpy-Si)] inside uniform Stöber silica nanoparticles was also achieved. The general methodology proposed could be applied to any silica matrix, allowed high grafting ratios that overcome chelate release and the tendency to agglomerate. Luminescent silica-based nanoparticles SiO2-[Eu(TTA)3(Bpy-Si)], with a diameter of 28 ± 2 nm, were successfully tested as a luminescent labels for the imaging of Pseudomonas aeruginosa biofilms. They were also functionalized by a specific monoclonal antibody and subsequently employed for the selective imaging of Escherichia coli bacteria.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Nanopartículas/química , Compuestos Organometálicos/química , Pseudomonas aeruginosa/crecimiento & desarrollo , Dióxido de Silicio/química , Europio/química , Luminiscencia , Compuestos Organometálicos/síntesis química , Compuestos de Organosilicio/química , Tamaño de la Partícula , Propiedades de Superficie
13.
Platelets ; 24(3): 219-25, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22646294

RESUMEN

Articular lesions are still a major challenge in orthopedics because of cartilage's poor healing properties. A major improvement in therapeutics was the development of autologous chondrocytes implantation (ACI), a biotechnology-derived technique that delivers healthy autologous chondrocytes after in vitro expansion. To obtain cartilage-like tissue, 3D scaffolds are essential to maintain chondrocyte differentiated status. Currently, bioactive 3D scaffolds are promising as they can deliver growth factors, cytokines, and hormones to the cells, giving them a boost to attach, proliferate, induce protein synthesis, and differentiate. Using mesenchymal stem cells (MSCs) differentiated into chondrocytes, one can avoid cartilage harvesting. Thus, we investigated the potential use of a platelet-lysate-based 3D bioactive scaffold to support chondrogenic differentiation and maintenance of MSCs. The MSCs from adult rabbit bone marrow (n = 5) were cultivated and characterized using three antibodies by flow cytometry. MSCs (1 × 10(5)) were than encapsulated inside 60 µl of a rabbit platelet-lysate clot scaffold and maintained in Dulbecco's Modified Eagle Medium Nutrient Mixture F-12 supplemented with chondrogenic inductors. After 21 days, the MSCs-seeded scaffolds were processed for histological analysis and stained with toluidine blue. This scaffold was able to maintain round-shaped cells, typical chondrocyte metachromatic extracellular matrix deposition, and isogenous group formation. Cells accumulated inside lacunae and cytoplasm lipid droplets were other observed typical chondrocyte features. In conclusion, the usage of a platelet-lysate bioactive scaffold, associated with a suitable chondrogenic culture medium, supports MSCs chondrogenesis. As such, it offers an alternative tool for cartilage engineering research and ACI.


Asunto(s)
Plaquetas , Cartílago , Condrogénesis/fisiología , Células Madre Mesenquimatosas/metabolismo , Ingeniería de Tejidos , Andamios del Tejido , Animales , Técnicas de Cultivo de Célula , Células Madre Mesenquimatosas/citología , Conejos
14.
Colloids Surf B Biointerfaces ; 214: 112447, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35334310

RESUMEN

The membrane of methicillin-resistant Staphylococcus aureus (MRSA) contains penicillin-binding proteins (PBPs) in the phospholipidic bilayer, with the protein PBP2a being linked with the resistance mechanism. In this work we confirm the role of PBP2a with molecular-level information obtained with Langmuir monolayers as cell membrane models. The MRSA cell membrane was mimicked with a mixed monolayer of dipalmitoyl phosphatidyl glycerol (DPPG) and cardiolipin (CL), also incorporating PBP2a. The surface pressure-area isotherms and the Brewster angle microscopy (BAM) images for these mixed monolayers were significantly affected by the antibiotic meropenem, which is PBP2a inhibitor. The meropenem effects were associated with the presence of PBP2a, as they were absent in the Langmuir monolayers without PBP2a. The relevance of PBP2a was confirmed with results where the antibiotic methicillin, known to be unsuitable to kill MRSA, had the same effects on mixed DPPG/CL and DPPG/CL-PBP2a monolayers since it prevented PBP2a from incorporating in the monolayer. The biological implication of the findings presented here is that a successful antibiotic against MRSA should be able to interact with PBP2a, but in the membrane.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Antibacterianos/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Meropenem/metabolismo , Meropenem/farmacología , Meticilina/farmacología , Pruebas de Sensibilidad Microbiana , Proteínas de Unión a las Penicilinas/metabolismo , Proteínas de Unión a las Penicilinas/farmacología
15.
Clin Chim Acta ; 531: 223-229, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35447142

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is the most common form of dementia and affect more than 50 million people worldwide. Thus, there is a high demand by non-invasive methods for an early diagnosis. This work explores the AD diagnostic using the amyloid beta 1-40 (Aß40) peptide encapsulated into dipalmitoyl phosphatidyl glycerol (DPPG) liposomes and immobilized on polyethylene imine previously deposited on screen-printed carbon electrodes to detect autoantibodies against Aß40, a potential biomarker found in plasma samples. METHODS: The immunosensor assembly was accompanied by atomic force microscopy (AFM) images that showed globular aggregates from 20 to 200 nm corresponding liposomes and by cyclic voltammetry (CV) through increase of the voltammogram area each material deposited. After building the immunosensor, when it was exposed to antibody anti-Aß40, there was an increase in film roughness of approximately 9 nm, indicating the formation of the immunocomplex. RESULTS: In the detection by CV, the presence of specific antibody, in the range of 0.1 to 10 µg/ml, resulted in an increase in the voltammograms area and current in 0.45 V reaching 3.2 µA.V and 5.7 µA, respectively, in comparison with the control system, which remained almost unchanged from 0.1 µg/ml. In patient samples, both cerebrospinal fluid (CSF) and plasma, was possible separated among positive and negative samples for AD using CV profile and area, with a difference of 0.1 µA.V from the upper error bar of healthy samples for CSF sample and 0.6 µA.V for plasma sample. CONCLUSIONS: These results showed the feasibility of the method employed for the non-invasive diagnostic of Alzheimer's disease detecting natural autoantibodies that circulate in plasma through a simple and easy-to-interpret method.


Asunto(s)
Enfermedad de Alzheimer , Técnicas Biosensibles , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Autoanticuerpos , Biomarcadores , Humanos , Inmunoensayo/métodos , Liposomas , Fragmentos de Péptidos
16.
Acta Cir Bras ; 35(12): e351207, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33503220

RESUMEN

PURPOSE: To evaluate the influence of mesenchymal stem cells from adipose tissue in the end-to-side neurorrhaphy, focusing in the nerve regeneration and the muscle reinnervation in acute trauma. METHODS: 140 animals were randomly divided in seven groups: control, denervated, end-to-side neurorrhaphy between distal stump of common peroneal nerve and tibial nerve (ESN), ESN wrapped in fascia, ESN wrapped in fascia and platelet gel, ESN wrapped in platelet gel, ESN wrapped in fascia and platelet gel within stem cells (without culture) removed from the adipose tissue. Mass measurements of the animal and of cranial tibial muscles, electromyography, walking track analysis tests and histological examinations of the nerves and muscles after 180 days was performed. RESULTS: In the groups where the ESN was performed, the results were always better when compared to the denervated group, showing reinnervation in all ESN groups. The most sensitive methods were walking track and histological analysis. Only the group with stem cells showed values similar to the control group, as well as the functional indices of peroneal nerve and the number of nerve fibers in the peroneal nerve. CONCLUSIONS: Stem cells were effective in ESN according with the functional index of the peroneal nerve, evaluated by walking track analysis and the number of nerve fibers in the peroneal nerve.


Asunto(s)
Nervio Peroneo , Nervio Tibial , Animales , Músculo Esquelético , Regeneración Nerviosa , Procedimientos Neuroquirúrgicos , Ratas , Células Madre , Nervio Tibial/cirugía
17.
Front Immunol ; 12: 760817, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34950138

RESUMEN

Monoclonal antibodies (mAbs) have been a valuable tool to elucidate several biological processes, such as stem cell differentiation and cancer, and contributed to virtually all areas of biomedical sciences. Yet, it remains a challenge to obtain mAbs specific to poorly expressed epitopes, or to epitopes that are actually involved in important biological phenomena, such as cell differentiation and metastasis. Drug-induced subtractive immunization, and recently the multiple tolerization subtractive immunization (MTSI) technique, reported by our group, have the potential to level up the field, as they direct the host´s immune response towards these epitopes. However, due to cyclophosphamide (CY) treatment, high mice mortality can be observed, and only a few data are available on how these techniques affect the immune system of mice. Tolerogen and immunogen cells, RWPE-1 and PC-3 cells, respectively, were individually seeded at 2 × 104 cells/cm2, and then adjusted to 2 × 106 cells per mouse before immunization, which was conducted in a subtractive approach (MTSI) with CY. Immunosuppression of mice was recorded via total white blood counting, as well the reactivity of circulating polyclonal antibodies (pAbs). General parameters, including weight, physical appearance, and behavior on mice subjected to three different concentrations of CY were recorded. mAbs were obtained using classical hybridoma techniques, using the spleen of immunized mice. After purification, antibodies were characterized by Western blotting, and Indirect immunofluorescence. In conclusion, all CY dosage were efficient in creating an immunosuppression state, but only the 100 mg/kg body weight was feasible, as the others resulted in extensive mice mortality. pAbs obtained in the peripheral blood of mice showed more reactivity towards tumor cells. MAbs 2-7A50 and 2-5C11 recognized antigens from tumor cells, but not from their non-tumor counterparts, as shown in western blotting and immunofluorescence assays. MTSI technique was successful in generating mAbs that recognize tumor-specific antigens.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Ciclofosfamida/administración & dosificación , Terapia de Inmunosupresión/métodos , Inmunosupresores/administración & dosificación , Animales , Especificidad de Anticuerpos , Línea Celular , Epítopos/inmunología , Humanos , Recuento de Leucocitos , Masculino , Ratones Endogámicos BALB C
18.
J Orthop Surg Res ; 16(1): 283, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33910605

RESUMEN

BACKGROUND: Platelet-rich plasma (PRP) has been used to favor anterior cruciate ligament (ACL) healing after reconstruction surgeries. However, clinical data are still inconclusive and subjective about PRP. Thus, we propose a quantitative method to demonstrate that PRP produced morphological structure changes. METHODS: Thirty-four patients undergoing ACL reconstruction surgery were evaluated and divided into control group (sixteen patients) without PRP application and experiment group (eighteen patients) with intraoperative application of PRP. Magnetic resonance imaging (MRI) scans were performed 3 months after surgery. We used Matlab® and machine learning (ML) in Orange Canvas® to texture analysis (TA) features extraction. Experienced radiologists delimited the regions of interest (RoIs) in the T2-weighted images. Sixty-two texture parameters were extracted, including gray-level co-occurrence matrix and gray level run length. We used the algorithms logistic regression (LR), naive Bayes (NB), and stochastic gradient descent (SGD). RESULTS: The accuracy of the classification with NB, LR, and SGD was 83.3%, 75%, 75%, respectively. For the area under the curve, NB, LR, and SGD presented values of 91.7%, 94.4%, 75%, respectively. In clinical evaluations, the groups show similar responses in terms of improvement in pain and increase in the IKDC index (International Knee Documentation Committee) and Lysholm score indices differing only in the assessment of flexion, which presents a significant difference for the group treated with PRP. CONCLUSIONS: Here, we demonstrated quantitatively that patients who received PRP presented texture changes when compared to the control group. Thus, our findings suggest that PRP interferes with morphological parameters of the ACL. TRIAL REGISTRATION: Protocol no. CAAE 56164316.6.0000.5411.


Asunto(s)
Ligamento Cruzado Anterior/patología , Ligamento Cruzado Anterior/cirugía , Procedimientos Ortopédicos/métodos , Procedimientos de Cirugía Plástica/métodos , Plasma Rico en Plaquetas , Adulto , Ligamento Cruzado Anterior/diagnóstico por imagen , Ligamento Cruzado Anterior/fisiopatología , Femenino , Humanos , Cuidados Intraoperatorios , Modelos Logísticos , Aprendizaje Automático , Imagen por Resonancia Magnética , Masculino , Cicatrización de Heridas
19.
Stem Cell Res Ther ; 12(1): 303, 2021 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-34051869

RESUMEN

BACKGROUND: Nerve injuries are debilitating, leading to long-term motor deficits. Remyelination and axonal growth are supported and enhanced by growth factor and cytokines. Combination of nerve guidance conduits (NGCs) with adipose-tissue-derived multipotent mesenchymal stromal cells (AdMSCs) has been performing promising strategy for nerve regeneration. METHODS: 3D-printed polycaprolactone (PCL)-NGCs were fabricated. Wistar rats subjected to critical sciatic nerve damage (12-mm gap) were divided into sham, autograft, PCL (empty NGC), and PCL + MSCs (NGC multi-functionalized with 106 canine AdMSCs embedded in heterologous fibrin biopolymer) groups. In vitro, the cells were characterized and directly stimulated with interferon-gamma to evaluate their neuroregeneration potential. In vivo, the sciatic and tibial functional indices were evaluated for 12 weeks. Gait analysis and nerve conduction velocity were analyzed after 8 and 12 weeks. Morphometric analysis was performed after 8 and 12 weeks following lesion development. Real-time PCR was performed to evaluate the neurotrophic factors BDNF, GDNF, and HGF, and the cytokine and IL-10. Immunohistochemical analysis for the p75NTR neurotrophic receptor, S100, and neurofilament was performed with the sciatic nerve. RESULTS: The inflammatory environment in vitro have increased the expression of neurotrophins BDNF, GDNF, HGF, and IL-10 in canine AdMSCs. Nerve guidance conduits multi-functionalized with canine AdMSCs embedded in HFB improved functional motor and electrophysiological recovery compared with PCL group after 12 weeks. However, the results were not significantly different than those obtained using autografts. These findings were associated with a shift in the regeneration process towards the formation of myelinated fibers. Increased immunostaining of BDNF, GDNF, and growth factor receptor p75NTR was associated with the upregulation of BDNF, GDNF, and HGF in the spinal cord of the PCL + MSCs group. A trend demonstrating higher reactivity of Schwann cells and axonal branching in the sciatic nerve was observed, and canine AdMSCs were engrafted at 30 days following repair. CONCLUSIONS: 3D-printed NGCs multi-functionalized with canine AdMSCs embedded in heterologous fibrin biopolymer as cell scaffold exerted neuroregenerative effects. Our multimodal approach supports the trophic microenvironment, resulting in a pro-regenerative state after critical sciatic nerve injury in rats.


Asunto(s)
Células Madre Mesenquimatosas , Animales , Perros , Regeneración Nerviosa , Impresión Tridimensional , Ratas , Ratas Wistar , Células de Schwann , Nervio Ciático
20.
Exp Parasitol ; 126(4): 621-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20542032

RESUMEN

Cysticercosis is a major cause of economic loss in bovine production due to meat condemnation. Chemotherapy is being used in Brazilian cattle and a diagnostic test to improve the treatment program is desired. We produced monoclonal antibodies against crude (TAEB) and cyst fluid (TAEF) Taenia saginata metacestode antigens using immunized BALB/c mice. After cell fusion, 10 TAEB and nine TAEF hybrids were selected and cloned resulting in 18 IgG(1) and 32 IgM TAEB clones, and 9 IgG(1) and 9 IgM TAEF clones. Ascites was produced and Western blot testing was performed resulting in reactivity to protein fractions of low molecular weight (<18kDa), 43, 55, 66 and 100kDa. The indirect immunofluorescence test, with one monoclonal antibody against crude and one against cyst fluid antigens, recognized antigenic fractions of both the scolex and the bladder wall of metacestodes from naturally infected bovine.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Antígenos Helmínticos/inmunología , Taenia saginata/inmunología , Animales , Anticuerpos Monoclonales/química , Antígenos Helmínticos/química , Western Blotting , Bovinos , Enfermedades de los Bovinos/diagnóstico , Cisticercosis/diagnóstico , Cisticercosis/veterinaria , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Hibridomas , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Conejos
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