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Oral-maxillofacial tumor removal can generate critical bone defects and major problems for patients, causing dysfunctionalities and affecting oral competencies such as mastication, swallowing, and breathing. The association of novel biomaterials and cell therapies in tissue engineering strategies could offer new strategies to promote osteomucosa healing. This study focused on the development of a bioengineered construct loaded with human dental follicle cells (MSCs). To increase the bioconstruct integration to the surrounding tissue, a novel and comprehensive approach was designed combining an injectable biomimetic hydrogel and dental stem cells (hDFMSCs) expressing luminescence/fluorescence for semi-quantitative tissue imaging in live animals. This in vivo model with human MSCs was based on an intramembranous bone regeneration process (IMO). Biologically, the biocomposite based on collagen/nanohydroxyapatite filled with cell-loaded osteopontin-fibrin hydrogel (Coll/nanoHA OPN-Fb) exhibited a high cellular proliferation rate, increased bone extracellular matrix deposition (osteopontin) and high ALP activity, indicating an early osteogenic differentiation. Thus, the presence of human OPN enhanced hDFMSC adhesion, migration, and spatial distribution within the 3D matrix. The developed 3D bioconstruct provided the necessary pro-regenerative effect to modulate the biological response, precisely fitting the bone defect with fine-tuned adjustment to the surrounding original structure and promoting oral osteomucosa tissue regeneration. We were also able to track the cells in vivo and evaluate their behavior (migration, proliferation, and differentiation), providing a glimpse into bone regeneration and helping in the optimization of patient-specific therapies.
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Células Madre Mesenquimatosas , Osteogénesis , Animales , Humanos , Osteopontina/genética , Osteopontina/metabolismo , Células Cultivadas , Biomimética , Células Madre Mesenquimatosas/metabolismo , Regeneración Ósea , Ingeniería de Tejidos/métodos , Diferenciación Celular , Hidrogeles/metabolismo , Andamios del Tejido/químicaRESUMEN
One of the complex challenges faced presently by tissue engineering (TE) is the development of vascularized constructs that accurately mimic the extracellular matrix (ECM) of native tissue in which they are inserted to promote vessel growth and, consequently, wound healing and tissue regeneration. TE technique is characterized by several stages, starting from the choice of cell culture and the more appropriate scaffold material that can adequately support and supply them with the necessary biological cues for microvessel development. The next step is to analyze the attained microvasculature, which is reliant on the available labeling and microscopy techniques to visualize the network, as well as metrics employed to characterize it. These are usually attained with the use of software, which has been cited in several works, although no clear standard procedure has been observed to promote the reproduction of the cell response analysis. The present review analyzes not only the various steps previously described in terms of the current standards for evaluation, but also surveys some of the available metrics and software used to quantify networks, along with the detection of analysis limitations and future improvements that could lead to considerable progress for angiogenesis evaluation and application in TE research.
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Angiogénesis , Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Técnicas de Cultivo de Célula/métodos , Microvasos , Fenómenos Fisiológicos Cardiovasculares , Matriz Extracelular , Andamios del TejidoRESUMEN
One of the most serious complications following the implantation of orthopedic biomaterials is the development of infection. Orthopedic implant-related infections do not only entail clinical problems and patient suffering, but also cause a burden on healthcare care systems. Additionally, the ageing of the world population, in particular in developed countries, has led to an increase in the population above 60 years. This is a significantly vulnerable population segment insofar as biomaterials use is concerned. Implanted materials are highly susceptible to bacterial and fungal colonization and the consequent infection. These microorganisms are often opportunistic, taking advantage of the weakening of the body defenses at the implant surface-tissue interface to attach to tissues or implant surfaces, instigating biofilm formation and subsequent development of infection. The establishment of biofilm leads to tissue destruction, systemic dissemination of the pathogen, and dysfunction of the implant/bone joint, leading to implant failure. Moreover, the contaminated implant can be a reservoir for infection of the surrounding tissue where microorganisms are protected. Therefore, the biofilm increases the pathogenesis of infection since that structure offers protection against host defenses and antimicrobial therapies. Additionally, the rapid emergence of bacterial strains resistant to antibiotics prompted the development of new alternative approaches to prevent and control implant-related infections. Several concepts and approaches have been developed to obtain biomaterials endowed with anti-infective properties. In this review, several anti-infective strategies based on biomaterial engineering are described and discussed in terms of design and fabrication, mechanisms of action, benefits, and drawbacks for preventing and treating orthopaedic biomaterials-related infections.
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Antiinfecciosos , Ortopedia , Antibacterianos/química , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Bacterias , Materiales Biocompatibles/química , Materiales Biocompatibles/uso terapéutico , Bioingeniería , Biopelículas , Humanos , Prótesis e Implantes/efectos adversosRESUMEN
An innovative delivery system based on bacteriophages-loaded alginate-nanohydroxyapatite hydrogel was developed as a multifunctional approach for local tissue regeneration and infection prevention and control. Bacteriophages were efficiently encapsulated, without jeopardizing phage viability and functionality, nor affecting hydrogel morphology and chemical composition. Bacteriophage delivery occurred by swelling-disintegration-degradation process of the alginate structure and was influenced by environmental pH. Good tissue response was observed following the implantation of bacteriophages-loaded hydrogels, sustaining their biosafety profile. Bacteriophages-loaded hydrogels did not affect osteoblastic cells' proliferation and morphology. A strong osteogenic and mineralization response was promoted through the implantation of hydrogels system with nanohydroxyapatite. Lastly, bacteriophages-loaded hydrogel showed excellent antimicrobial activity inhibiting the attachment and colonization of multidrug-resistant E. faecalis surrounding and within femoral tissues. This new local delivery approach could be a promising approach to prevent and control bacterial contamination during implantation and bone integration.
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Alginatos/química , Bacteriófagos/química , Hidrogeles/química , Antiinfecciosos/química , Bacteriófagos/fisiología , Proliferación Celular/efectos de los fármacos , Concentración de Iones de Hidrógeno , Ingeniería de Tejidos , Andamios del Tejido/químicaRESUMEN
One of the most important and novel approaches of biomedical engineering is the development of new, effective and non-invasive medical diagnosis abilities, and treatments that have such requirements as advanced technologies for tumor imaging. Gadolinium (Gd) compounds can be used as MRI contrast agents, however the release of Gd3+ ions presents some adverse side effects such as renal failure, pancreatitis or local necrosis. The main aim of the work was the development and optimization of Gadolinium based nanoparticles coated with silica to be used as bioimaging agent. Gd based nanoparticles were prepared through a precipitation method and afterwards, these nanoparticles were covered with silica, using Stöber method with ammonia and functionalized with 3-Aminopropyltriethoxysilane (APTES). Results showed that nanoparticles were homogeneous regarding chemical composition, silica layer thickness, total size and morphology. Also, silica coating was successfully not degraded after 4 weeks at pH 5.5, 6.0 and 7.4, contrary to GdOHCO3 nanoparticles that degraded. Regarding the in vitro cell tests, very good cell proliferation and viability were observed. In conclusion, the results showed that Gd based nanoparticles coated with silica for imaging applications were successfully obtained under a well-controlled method. Furthermore, silica coating may enhance magnetic nanoparticles biosafety because it avoids GdOHCO3 degradation into harmful products (such as Gd3+ ions) at physiological conditions.
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Gadolinio/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Dióxido de Silicio/química , Ingeniería Biomédica , Proliferación Celular , Supervivencia Celular , Medios de Contraste/química , Fibroblastos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/metabolismo , Imagen por Resonancia Magnética , Nanopartículas de Magnetita/química , Microscopía Electrónica de Transmisión , Necrosis/tratamiento farmacológico , Pancreatitis/tratamiento farmacológico , Propilaminas/química , Insuficiencia Renal/tratamiento farmacológico , Silanos/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos XRESUMEN
Dental ceramic implants have shown superior esthetic behavior and the absence of induced allergic disorders when compared to titanium implants. Zirconia may become a potential candidate to be used as an alternative to titanium dental implants if surface modifications are introduced. In this work, bioactive micropatterned silica coatings were produced on zirconia substrates, using a combined methodology of sol-gel processing and soft lithography. The aim of the work was to compare the in vitro behavior of human gingival fibroblasts (HGFs) and human dermal microvascular endothelial cells (HDMECs) on three types of silica-coated zirconia surfaces: flat and micropatterned (with pillars and with parallel grooves). Our results showed that cells had a higher metabolic activity (HGF, HDMEC) and increased gene expression levels of fibroblast-specific protein-1 (FSP-1) and collagen type I (COL I) on surfaces with pillars. Nevertheless, parallel grooved surfaces were able to guide cell growth. Even capillary tube-like networks of HDMEC were oriented according to the surface geometry. Zirconia and silica with different topographies have shown to be blood compatible and silica coating reduced bacteria adhesion. All together, the results indicated that microstructured bioactive coating seems to be an efficient strategy to improve soft tissue integration on zirconia implants, protecting implants from peri-implant inflammation and improving long-term implant stabilization. This new approach of micropatterned silica coating on zirconia substrates can generate promising novel dental implants, with surfaces that provide physical cues to guide cells and enhance their behavior.
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This study employs a meshless computational model to investigate the impacts of compression and traction on angiogenesis, exploring their effects on vascular endothelial growth factor (VEGF) diffusion and subsequent capillary network formation. Three distinct initial domain geometries were defined to simulate variations in endothelial cell sprouting and VEGF release. Compression and traction were applied, and the ensuing effects on VEGF diffusion coefficients were analysed. Compression promoted angiogenesis, increasing capillary network density. The reduction in the VEGF diffusion coefficient under compression altered VEGF concentration, impacting endothelial cell migration patterns. The findings were consistent across diverse simulation scenarios, demonstrating the robust influence of compression on angiogenesis. This computational study enhances our understanding of the intricate interplay between mechanical forces and angiogenesis. Compression emerges as an effective mediator of angiogenesis, influencing VEGF diffusion and vascular pattern. These insights may contribute to innovative therapeutic strategies for angiogenesis-related disorders, fostering tissue regeneration and addressing diseases where angiogenesis is crucial.
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Nanoparticle (NP) research is an area of scientific interest with high potential for application in biomedical, optical, and electronic fields. Due to their relatively large surface area compared to their mass, NPs can be more chemically reactive and change their reactive strength or other properties. NP-based drug delivery systems provide transport and an effective and controlled way to release the drugs. This work aimed to study the solubility and biological activity of nano-encapsulated copper metal complexes for the induction of toxicity and mortality in larvae of Aedes aegypti mosquitoes. After the nano-encapsulated metal complexes were prepared, the efficiency of this incorporation was determined by electron paramagnetic resonance, and toxicity bioassays were performed. The polymeric-based PLGA NPs encapsulating metal complexes exhibited high toxicity and specificity for target organisms (insect vectors, i.e., A. aegypti), with relatively less environmental impact and long-term control of their breeding.
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Tissue regeneration of large bone defects is still a clinical challenge. Bone tissue engineering employs biomimetic strategies to produce graft composite scaffolds that resemble the bone extracellular matrix to guide and promote osteogenic differentiation of the host precursor cells. Aerogel-based bone scaffold preparation methods have been increasingly improved to overcome the difficulties in balancing the need for an open highly porous and hierarchically organized microstructure with compression resistance to withstand bone physiological loads, especially in wet conditions. Moreover, these improved aerogel scaffolds have been implanted in vivo in critical bone defects, in order to test their bone regeneration potential. This review addresses recently published studies on aerogel composite (organic/inorganic)-based scaffolds, having in mind the various cutting-edge technologies and raw biomaterials used, as well as the improvements that are still a challenge in terms of their relevant properties. Finally, the lack of 3D in vitro models of bone tissue for regeneration studies is emphasized, as well as the need for further developments to overcome and minimize the requirement for studies using in vivo animal models.
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Local delivery of antibiotics has gained increasing interest in the treatment of osteomyelitis due to its effectiveness and safety. Since the regeneration of bone tissue at the site of infection is as important as bacterial eradication, implantable drug delivery systems should not only release the drugs in a proper manner but also exert the osseointegration capability. Herein, we present an implantable drug delivery system in a scaffold form with a unique set of features for local treatment of osteomyelitis. For the first time, collagen type I, ciprofloxacin-loaded mesoporous silica, and bioglass were combined to obtain scaffolds using the molding method. Drug-loaded mesoporous silica was blended with polydimethylsiloxane to prolong the drug release, whereas bioglass served as a remineralization agent. Collagen-silica scaffolds were evaluated in terms of physicochemical properties, drug release rate, mineralization potential, osteoblast response in vitro, antimicrobial activity, and biological properties using an in vivo preclinical model - chick embryo chorioallantoic membrane (CAM). The desirable multifunctionality of the proposed collagen-silica scaffolds was confirmed. They released the ciprofloxacin for 80 days, prevented biofilm development, and induced hydroxyapatite formation. Moreover, the resulting macroporous structure of the scaffolds promoted osteoblast attachment, infiltration, and proliferation. Collagen-silica scaffolds were also biocompatible and effectively integrated with CAM.
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Antibacterianos , Osteomielitis , Embrión de Pollo , Animales , Antibacterianos/farmacología , Andamios del Tejido/química , Dióxido de Silicio/química , Sistemas de Liberación de Medicamentos , Colágeno/química , Huesos , Ciprofloxacina/farmacología , Osteomielitis/tratamiento farmacológico , Porosidad , Materiales Biocompatibles/química , Regeneración ÓseaRESUMEN
Despite bone's innate self-renewal capability, some periodontal pathologic and traumatic defects' size inhibits full spontaneous regeneration. This current research characterized a 3D porous biodegradable nano-hydroxyapatite/chitosan (nHAp/CS, 70/30) scaffold for periodontal bone regeneration, which preparation method includes the final solvent extraction and sterilization through supercritical CO2 (scCO2). Micro-CT analysis revealed the fully interconnected porous microstructure of the nHAp/CS scaffold (total porosity 78 %, medium pore size 200 µm) which is critical for bone regeneration. Scanning electron microscopy (SEM) showed HAp crystals forming on the surface of the nHAp/CS scaffold after 21 days in simulated body fluid, demonstrating its bioactivity in vitro. The presence of nHAp in the scaffolds promoted a significantly lower biodegradation rate compared to a plain CS scaffold in PBS. Dynamic mechanical analysis confirmed their viscoelasticity, but the presence of nHAp significantly enhanced the storage modulus (42.34 ± 6.09 kPa at 10 Hz after 28 days in PBS), showing that it may support bone ingrowth at low-load bearing bone defects. Both scaffold types significantly inhibited the growth, attachment and colony formation abilities of S. aureus and E. coli, enhancing the relevance of chitosan in the grafts' composition for the naturally contaminated oral environment. At SEM and laser scanning confocal microscopy, MG63 cells showed normal morphology and could adhere and proliferate inside the biomaterials' porous structure, especially for the nHAp/CS scaffold, reaching higher proliferative rate at day 14. MG63 cells seeded within nHAp/CS scaffolds presented a higher expression of RUNX2, collagen A1 and Sp7 osteogenic genes compared to the CS samples. The in vivo subcutaneous implantation in mice of both scaffold types showed lower biodegradability with the preservation of the scaffolds porous structure that allowed the ingrowth of connective tissue until 5 weeks. Histology shows an intensive and progressive ingrowth of new vessels and collagen between the 3rd and the 5th week, especially for the nHAp/CS scaffold. So far, the scCO2 method enabled the production of a cost-effective and environment-friendly ready-to-use nHAp/CS scaffold with microstructural, chemical, mechanical and biocompatibility features that make it a suitable bone graft alternative for defect sites in an adverse environment as in periodontitis and peri-implantitis.
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Quitosano , Ratones , Animales , Quitosano/química , Quitosano/farmacología , Durapatita/química , Durapatita/farmacología , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Dióxido de Carbono , Escherichia coli , Staphylococcus aureus , Regeneración Ósea , Colágeno/química , EsterilizaciónRESUMEN
Lung cancer (LC) is a major cause of mortality. Late diagnosis, associated with limitations in tissue biopsies for adequate tumor characterization contribute to limited survival of lung cancer patients. Liquid biopsies have been introduced to improve tumor characetrization through the analysis of biomarkers, including circulating tumour cells (CTCs) and cell-free DNA (cfDNA). Considering their availability in blood, several enrichment strategies have been developed to augment circulating biomarkers for improving diagnostic, prognostic and treament efficacy assessment; often, however, only one biomarker is tested. In this work we developed and implemented a microfluidic chip for label-free enrichment of CTCs with a methodology for subsequent cfDNA analysis from the same cryopreserved sample. CTCs were successfully isolated in 38 of 42 LC patients with the microfluidic chip. CTCs frequency was significantly higher in LC patients with advanced disease. A cut-off of 1 CTC per mL was established for diagnosis (sensitivity = 76.19%, specificity = 100%) and in patients with late stage lung cancer, the presence of ≥5 CTCs per mL was significantly associated with shorter overall survival. MIR129-2me and ADCY4me panel of cfDNA methylation performed well for LC detection, whereas MIR129-2me combined with HOXA11me allowed for patient risk stratification. Analysis of combinations of biomarkers enabled the definition of panels for LC diagnosis and prognosis. Overall, this study demonstrates that multimodal analysis of tumour biomarkers via microfluidic devices may significantly improve LC characterization in cryopreserved samples, constituting a reliable source for continuous disease monitoring.
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Ácidos Nucleicos Libres de Células , Neoplasias Pulmonares , Células Neoplásicas Circulantes , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Metilación , Microfluídica/métodos , Células Neoplásicas Circulantes/patologíaRESUMEN
Practices such as "Reiki", therapeutic touch, healing touch, and external "Qigong" have been regarded as some form of "energy medicine" or "biofield therapy". The biofield concept has been studied and debated by researchers of distinct areas of expertise, and although the phenomenon was sometimes described as physically related to electromagnetics, other factors such as "subtle energy" and focused intention might be involved. These nonconventional practices integrate contact and non-contact techniques, and those dealing with so-called distant healing interventions are perhaps the most difficult to understand and accept. Practitioners describe these so-called nonlocal interventions as involving intentional factors and particular states of consciousness. With a spiritual mindset and a particular state of awareness, compassion is said to work out as a catalyst to produce physiological and physical changes through mechanisms that are still unknown. At the body level, these vegetative changes might be related to individual self-perception variations as part of the body neurovegetative feedback system of regulation. Further mechanisms are difficult to document and measure, and might be more accessible to research by using physical signal detectors, chemical dynamics methods, detectors using biological materials, detectors using living sensors, and detectors using the human body. The growing interest in these practices and the considerable amount of research exploring their effects and clinical applications encouraged this narrative review, which aims to provide an easy to consult partial overview of the history, theory and findings of quantitative research strategies exploring non-contact biofield-based practices. This work also aims to stimulate the reader's mind with the raised hypotheses, catalyzing further research on the subject to confirm or deny the reported outcomes.
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Terapias Mente-Cuerpo , Qigong , Estado de Conciencia , Fenómenos Electromagnéticos , Humanos , IntenciónRESUMEN
Traditional Chinese medicine (TCM) is a systematic healthcare system developed from clinical experience based on a scientific model of regulation. TCM relies on unique theories and practices to treat diseases and enhance health. These practices include Chinese herbal medicine and dietetics, acupuncture and moxibustion, and other non-medication therapies such as Chinese bodywork or manual therapy, known as "Tuina", and traditional biofeedback exercises, known as "Qigong" and "Taijiquan". The integration of TCM in Western health systems and research requires a rational communicable theory, scientific proof of efficacy and safety, and quality control measures. Understanding the structural concepts of the TCM language makes possible the parallelism to Western physiology, and the inherent rational use of the reflex therapeutic systems, anti-inflammatory mechanisms and mental training involved, for example, in acupuncture and "Qigong". The results of TCM clinical trials and fundamental research on its nature and mechanisms have encouraged the development and application of well-designed research strategies such as double blinding in acupucture to overcome limitations and resistances in integrating these practices into the existing biomedical paradigms of the West. This review aims to overview some TCM theoretical concepts and the evidence-based clinical application of TCM's leading practices to create an easy-to-consult and condensed source of information, available for the healthcare community, facilitating the understanding and communication between conventional health professionals and TCM practitioners and acupuncturists.
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The integration of Traditional Chinese Medicine (TCM) in Western health systems and research requires a rational communicable theory, scientific proof of efficacy and safety, and quality control measures. The existence of clear definitions and the diagnosis standardization are critical factors to establish the patient's vegetative functional status accurately and, therefore, systematically apply TCM therapeutics such as the stimulation of reflex skin areas known as acupoints. This science-based conceptualization entails using validated methods, or even developing new systems able to parameterize the diagnosis and assess TCM related effects by objective measurements. Traditionally, tongue and pulse diagnosis and the functional evaluation of action points by pressure sensitivity and physical examination may be regarded as essential diagnostic tools. Parameterizing these techniques is a future key point in the objectification of TCM diagnosis, such as by electronic digital image analysis, mechanical pulse diagnostic systems, or the systematic evaluation of acupoints' electrophysiology. This review aims to demonstrate and critically analyze some achievements and limitations in the clinical application of device-assisted TCM diagnosis systems to evaluate functional physiological patterns. Despite some limitations, tongue, pulse, and electrophysiological diagnosis devices have been reported as a useful tool while establishing a person's functional status.
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INTRODUCTION: Acupoints have bioelectrical properties distinct from common skin. Besides the higher electrical conductivity and lower resistance, acupoints show capacitor-like properties, which can be related to their endogenous electrical potential. Traditional Chinese Medicine (TCM) postulates that meridians are physiological structures connecting acupoints and working as a conduit for the flow of two essential substances known as qi and xue. OBJECTIVES: This pilot study was focused in evaluating whether the electrical potential of acupoints can be correlated objectively to the functional properties as described by ancient Chinese medical theories, such as the theories of coupled meridians of the same phase ('elements'), and the principle of coupled points. METHODS: Direct needle moxibustion on LU5 and needle dispulsion of LI4 were performed in 21 subjects. The electrical potential of each acupoint was measured with a high-resolution data acquisition system taking to reference the acupoint SP6 of the Spleen conduit. RESULTS: The results may indicate a functional relationship between the therapeutics and the electrical potential response on the selected acupoints. These effects seem to be explainable considering the specific properties of each acupoint, the relationship between TCM phases, and the dynamics between coupled conduits. CONCLUSION: The evaluation of the endogenous electrical potential of acupoints and the changes caused by an external stimulus might contribute to the understanding of TCM concepts, mechanisms, and the effects of associated therapeutics. The observed phenomena encourage the systematic assessment of the functional vegetative status via skin electrophysiology and using objective measurements.
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Terapia por Acupuntura , Meridianos , Moxibustión , Puntos de Acupuntura , Análisis de Datos , Humanos , Proyectos PilotoRESUMEN
Background The biofield is a controversial concept among the scientific community. Some aspects of this phenomenon relate to measurable factors of mainstream science such as electromagnetics, while others, involving nonlocal interventions, intention, and consciousness, seem to produce physical changes through mechanisms that are still unknown, making the outcomes of many studies not fully explained by our current state of scientific understanding. This study explored the hypothetical effects of intention on the conditioning of a pH system with continuous data acquisition for real-time measurements. As a follow-up study, those effects were related to changes in the physicochemical properties of water samples chosen as a target in a previous large-scale intervention of focused intention. Methods The intention experiments were conducted under controlled conditions from the 8th to September 11, 2015. During this period, 286 qualified biofield therapy practitioners meditated at a distance with the intention of changing the vibrational state of the water molecules contained in specific flasks. Several variables were evaluated, including the magnetic field and ultraviolet-visible (UV-VIS) radiation from 175 to 954ânm near the experimental spot, as well as Raman spectra, pH, and electrical conductivity of all the water samples. After this period, real-time pH measurements of water samples were taken with the same equipment and under the same experimental conditions, except for the practitioners' awareness of those experiments, and without their focused intention. Real-time pH, electrical conductivity and the concentration of cations and anions measured by ion chromatography in the water samples were used to test the proposed hypothesis. Results Real-time pH was responsive during the intention experiments and after this period. Further continuous measurements performed after the 11th September showed that the pH variations overtime kept a systematic and consistent tendency similar to the one observed during the experimental activities involving focused intention. After the replacement of the electrode internal electrolyte, this behavior was no longer verified, and the pH was stable as the initial tests to evaluate the equipment sensitivity. Conclusions After the experimental period involving focused intention, the pH system maintained a systematic and consistent behavior while measuring the pH of new water samples. An eventual intention-mediated conditioning of the pH measurement system occurred because of changes in the properties of the electrode internal electrolyte.
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In guided bone tissue engineering, successful ingrowth of MSCs depends primarily on the nature of the scaffold. It is well-known that only seconds after implantation, biomaterials are coated by a layer of adsorbed proteins/peptides which modulates the subsequent cell/scaffold interactions, especially at early times after implantation. In this work, nanohydroxyapatite and collagen based composite materials (Coll/nanoHA) were modified with phosphorylated amino acid (O-phospho-L-serine-OPS) to mimic bone tissue, and induce cell differentiation. The choice for this phosphorylated amino acid is due to the fact that osteopontin is a serine-rich glycol-phosphoprotein and has been associated to the early stages of bone formation, and regeneration. Several concentrations of OPS were added to the Coll/nanoHA scaffold and physico-chemical, mechanical, and in vitro cell behavior were evaluated. Afterwards, the composite scaffold with stronger mechanical and best cellular behavior was tested in vivo, with or without previous in vitro culture of human MSC's (bone tissue engineering). The OPS signaling of the biocomposite scaffolds showed similar cellular adhesion and proliferation, but higher ALP enzyme activity (HBMSC). In vivo bone ectopic formation studies allowed for a thorough evaluation of the materials for MSC's osteogenic differentiation. The OPS-scaffolds results showed that the material could modulated mesenchymal cells behavior in favor of osteogenic differentiation into late osteoblasts that gave raised to their ECM with human bone proteins (osteopontin) and calcium deposits. Finally, OPS-modified scaffolds enhanced cell survival, engraftment, migration, and spatial distribution within the 3D matrix that could be used as a cell-loaded scaffold for tissue engineering applications and accelerate bone regeneration processes.
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Qigong is a therapeutic method of traditional Chinese medicine (TCM) that combines slow, soft movements and postures with breath control and a special mental state of 'awareness'. TCM holds that the practice of Qigong promotes the 'circulation of qi' in the human body, the 'flow' of upward yang qi and downward yin qi to establish 'balance'. In Western terms, this may be generally equivalent to vegetative homeostasis and the emotionally balanced state induced thereby. Researchers have often attempted to evaluate the functional movements of qi using measurements of the skin's electrical resistance. However, these methodologies have proven difficult to gauge, validate, repeat, and interpret. We aimed to overcome these limitations by measuring the skin's electrical potential between two points of the same system. The main goal of this study was to assess the skin's electrical potential changes in acupoints from the Ren Mai and Du Mai conduits, or meridians, as well as in other points of interest, during Qigong practice. While participants performed a specific Qigong exercise called 'White Ball', we observed significant changes in the skin electrical potential on Mìngmén (GV 4), Shèndáo (GV 11) and Baihuì (GV 20), from the Du Mai conduit, as well as on Huiyin (CV 1), Qìhai (CV 6), Zhongwan (CV 12) and Dànzhong (CV 17), from Ren Mai. These observations are in accordance with TCM theory and may contribute to the explanation of the vegetative physiological changes that are associated with 'qi flow' in TCM.
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Puntos de Acupuntura , Qigong/métodos , Fenómenos Fisiológicos de la Piel , Adulto , Electrodos , Humanos , Masculino , Microcirculación/fisiología , Proyectos Piloto , TermografíaRESUMEN
BACKGROUND AND OBJECTIVE: Surface topography of biomaterials has been shown to have an effect on cells behaviour. Cell-material interactions can be visually characterized by assessing both cell shape and spreading at initial time-points and, its migration patterns, as a response to the underlying topography. Whilst many have reported the study of cell migration and shape with fluorescence labelling, the focus on evaluating cells response to surface topography is to observe, under real-time conditions, interactions between cells and surfaces. In this manuscript we present a novel approach to automatically detect and remove periodic background patterns in brightfield microscopy images in order to perform automatic cell mobility analysis. METHODS: The developed software, MobilityAnalyser, performs automatic tracking of unmarked cells and allows the user to manually correct any incorrectly detected or tracked cell. Human Mesenchymal Stem Cells (hMSCs) trajectory, migration distance, velocity and persistence were evaluated over line and pillar micropatterned SiO2 films and on a flat SiO2 control substrate. RESULTS: The developed software proved to be effective in automatically removing background patterns of both line and pillar shapes and in performing cell detection and tracking. MobilityAnalyser accurately measured cell mobility in a fraction of the time required for manual analysis and eliminated user subjectivity. The results obtained with the software confirmed how different topographies affect cell trajectory, migration pathways and velocities, with a statistically significant increase for micropatterned surfaces, when compared with the flat control. The persistence parameter also proved the influence of both patterns on the directionality of cell movement. CONCLUSIONS: MobilityAnalyser is an automatic tool that removes periodic background patterns, detects and tracks cells, and provides cell mobility parameters that characterize the response of cells to different surface topographies. The software is freely available at: https://drive.google.com/open?id=1Fbb321ogLD19SlRjceMETNUqDHgpeBPl.