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1.
Adv Mater ; 35(33): e2301819, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37352307

ABSTRACT

In nanothermometry, the use of nanoparticles as thermal probes enables remote and minimally invasive sensing. In the biomedical context, nanothermometry has emerged as a powerful tool where traditional approaches, like infrared thermal sensing and contact thermometers, fall short. Despite the strides of this technology in preclinical settings, nanothermometry is not mature enough to be translated to the bedside. This is due to two major hurdles: the inability to perform 3D thermal imaging and the requirement for tools that are readily available in the clinics. This work simultaneously overcomes both limitations by proposing the technology of optical coherence thermometry (OCTh). This is achieved by combining thermoresponsive polymeric nanogels and optical coherence tomography (OCT)-a 3D imaging technology routinely used in clinical practice. The volume phase transition of the thermoresponsive nanogels causes marked changes in their refractive index, making them temperature-sensitive OCT contrast agents. The ability of OCTh to provide 3D thermal images is demonstrated in tissue phantoms subjected to photothermal processes, and its reliability is corroborated by comparing experimental results with numerical simulations. The results included in this work set credible foundations for the implementation of nanothermometry in the form of OCTh in clinical practice.


Subject(s)
Nanoparticles , Thermometry , Nanogels , Reproducibility of Results , Thermometers , Polymers , Tomography, Optical Coherence/methods
2.
Nanomedicine ; 43: 102556, 2022 07.
Article in English | MEDLINE | ID: mdl-35390527

ABSTRACT

There is an urgent need for contrast agents to detect the first inflammation stage of atherosclerosis by cardiovascular optical coherence tomography (CV-OCT), the imaging technique with the highest spatial resolution and sensitivity of those used during coronary interventions. Gold nanoshells (GNSs) provide the strongest signal by CV-OCT. GNSs are functionalized with the cLABL peptide that binds specifically to the ICAM-1 molecule upregulated in the first stage of atherosclerosis. Dark field microscopy and CV-OCT are used to evaluate the specific adhesion of these functionalized GNSs to activated endothelial cells. This adhesion is investigated under static and dynamic conditions, for shear stresses comparable to those of physiological conditions. An increase in the scattering signal given by the functionalized GNSs attached to activated cells is observed compared to non-activated cells. Thus, cLABL-functionalized GNSs behave as excellent contrast agents for CV-OCT and promise a novel strategy for clinical molecular imaging of atherosclerosis.


Subject(s)
Atherosclerosis , Tomography, Optical Coherence , Atherosclerosis/diagnostic imaging , Contrast Media , Endothelial Cells , Gold , Humans , Tomography, Optical Coherence/methods
3.
ACS Photonics ; 9(2): 559-566, 2022 Feb 16.
Article in English | MEDLINE | ID: mdl-35224134

ABSTRACT

Optical coherence tomography (OCT) is an imaging technique currently used in clinical practice to obtain optical biopsies of different biological tissues in a minimally invasive way. Among the contrast agents proposed to increase the efficacy of this imaging method, gold nanoshells (GNSs) are the best performing ones. However, their preparation is generally time-consuming, and they are intrinsically costly to produce. Herein, we propose a more affordable alternative to these contrast agents: Bi2Se3 nanostructured clusters with a desert rose-like morphology prepared via a microwave-assisted method. The structures are prepared in a matter of minutes, feature strong near-infrared extinction properties, and are biocompatible. They also boast a photon-to-heat conversion efficiency of close to 50%, making them good candidates as photothermal therapy agents. In vitro studies evidence the prowess of Bi2Se3 clusters as OCT contrast agents and prove that their performance is comparable to that of GNSs.

4.
Antioxidants (Basel) ; 10(6)2021 May 25.
Article in English | MEDLINE | ID: mdl-34070392

ABSTRACT

The best conservation method for native Chilean berries has been investigated in combination with an implemented large-scale extract of maqui berry, rich in total polyphenols and anthocyanin to be tested in intestinal epithelial and immune cells. The methanolic extract was obtained from lyophilized and analyzed maqui berries using Folin-Ciocalteu to quantify the total polyphenol content, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) to measure the antioxidant capacity. Determination of maqui's anthocyanins profile was performed by ultra-high-performance liquid chromatography (UHPLC-MS/MS). Viability, cytotoxicity, and percent oxidation in epithelial colon cells (HT-29) and macrophages cells (RAW 264.7) were evaluated. In conclusion, preservation studies confirmed that the maqui properties and composition in fresh or frozen conditions are preserved and a more efficient and convenient extraction methodology was achieved. In vitro studies of epithelial cells have shown that this extract has a powerful antioxidant strength exhibiting a dose-dependent behavior. When lipopolysaccharide (LPS)-macrophages were activated, noncytotoxic effects were observed, and a relationship between oxidative stress and inflammation response was demonstrated. The maqui extract along with 5-aminosalicylic acid (5-ASA) have a synergistic effect. All of the compiled data pointed out to the use of this extract as a potential nutraceutical agent with physiological benefits for the treatment of inflammatory bowel disease (IBD).

6.
Adv Healthc Mater ; 10(10): e2002186, 2021 05.
Article in English | MEDLINE | ID: mdl-33594792

ABSTRACT

The unique combination of physical and optical properties of silica (core)/gold (shell) nanoparticles (gold nanoshells) makes them especially suitable for biomedicine. Gold nanoshells are used from high-resolution in vivo imaging to in vivo photothermal tumor treatment. Furthermore, their large scattering cross-section in the second biological window (1000-1700 nm) makes them also especially adequate for molecular optical coherence tomography (OCT). In this work, it is demonstrated that, after suitable functionalization, gold nanoshells in combination with clinical OCT systems are capable of imaging damage in the myocardium following an infarct. Since both inflammation and apoptosis are two of the main mechanisms underlying myocardial damage after ischemia, such damage imaging is achieved by endowing gold nanoshells with selective affinity for the inflammatory marker intercellular adhesion molecule 1 (ICAM-1), and the apoptotic marker phosphatidylserine. The results here presented constitute a first step toward a fast, safe, and accurate diagnosis of damaged tissue within infarcted hearts at the molecular level by means of the highly sensitive OCT interferometric technique.


Subject(s)
Myocardial Infarction , Nanoshells , Gold , Humans , Infarction , Molecular Imaging , Myocardial Infarction/diagnostic imaging
7.
Nanomaterials (Basel) ; 10(7)2020 Jul 19.
Article in English | MEDLINE | ID: mdl-32707641

ABSTRACT

The complexity of some diseases-as well as the inherent toxicity of certain drugs-has led to an increasing interest in the development and optimization of drug-delivery systems. Polymeric nanoparticles stand out as a key tool to improve drug bioavailability or specific delivery at the site of action. The versatility of polymers makes them potentially ideal for fulfilling the requirements of each particular drug-delivery system. In this review, a summary of the state-of-the-art panorama of polymeric nanoparticles as drug-delivery systems has been conducted, focusing mainly on those applications in which the corresponding disease involves an important morbidity, a considerable reduction in the life quality of patients-or even a high mortality. A revision of the use of polymeric nanoparticles for ocular drug delivery, for cancer diagnosis and treatment, as well as nutraceutical delivery, was carried out, and a short discussion about future prospects of these systems is included.

8.
Small ; 16(29): e1907171, 2020 07.
Article in English | MEDLINE | ID: mdl-32548926

ABSTRACT

Fast and precise localization of ischemic tissues in the myocardium after an acute infarct is required by clinicians as the first step toward accurate and efficient treatment. Nowadays, diagnosis of a heart attack at early times is based on biochemical blood analysis (detection of cardiac enzymes) or by ultrasound-assisted imaging. Alternative approaches are investigated to overcome the limitations of these classical techniques (time-consuming procedures or low spatial resolution). As occurs in many other fields of biomedicine, cardiological preclinical imaging can also benefit from the fast development of nanotechnology. Indeed, bio-functionalized near-infrared-emitting nanoparticles are herein used for in vivo imaging of the heart after an acute myocardial infarct. Taking advantage of the superior acquisition speed of near-infrared fluorescence imaging, and of the efficient selective targeting of the near-infrared-emitting nanoparticles, in vivo images of the infarcted heart are obtained only a few minutes after the acute infarction event. This work opens an avenue toward cost-effective, fast, and accurate in vivo imaging of the ischemic myocardium after an acute infarct.


Subject(s)
Myocardial Infarction , Nanoparticles , Humans , Luminescence , Myocardial Infarction/diagnostic imaging , Myocardium , Optical Imaging
9.
Nutrients ; 12(6)2020 Jun 11.
Article in English | MEDLINE | ID: mdl-32545398

ABSTRACT

Nutraceuticals include a wide variety of bioactive compounds, such as polyphenols, which have been highlighted for their remarkable health benefits. Specially, maqui berries have shown great antioxidant activity and anti-inflammatory effects on some inflammatory diseases. The objectives of the present study were to explore the therapeutic effects of maqui berries on acute-phase inflammation in Crohn's disease. Balb/c mice were exposed to 2,4,6-trinitrobenzene sulfonic acid (TNBS) via intracolonic administration. Polyphenolic maqui extract (Ach) was administered orally daily for 4 days after TNBS induction (Curative Group), and for 7 days prior to the TNBS induction until sacrifice (Preventive Group). Our results showed that both preventive and curative Ach administration inhibited body weight loss and colon shortening, and attenuated the macroscopic and microscopic damage signs, as well as significantly reducing transmural inflammation and boosting the recovery of the mucosal architecture and its muco-secretory function. Additionally, Ach promotes macrophage polarization to the M2 phenotype and was capable of down-regulating significantly the expression of inflammatory proteins COX-2 and iNOS, and at the same time it regulates the antioxidant Nrf-2/HO-1 pathway. In conclusion, this is the first study in which it is demonstrated that the properties of Ach as could be used as a preventive and curative treatment in Crohn's disease.


Subject(s)
Anti-Inflammatory Agents , Antioxidants , Crohn Disease/chemically induced , Crohn Disease/therapy , Dietary Supplements , Fruit/chemistry , Heme Oxygenase-1/metabolism , Membrane Proteins/metabolism , NF-E2-Related Factor 2/metabolism , Nutritional Physiological Phenomena/physiology , Phytotherapy , Polyphenols/pharmacology , Polyphenols/therapeutic use , Signal Transduction/drug effects , Trinitrobenzenesulfonic Acid/adverse effects , Acute-Phase Reaction , Administration, Oral , Animals , Crohn Disease/genetics , Crohn Disease/prevention & control , Cyclooxygenase 2/metabolism , Disease Models, Animal , Inflammation Mediators/metabolism , Male , Mice, Inbred BALB C , Nitric Oxide Synthase Type II/metabolism , Polyphenols/administration & dosage , Polyphenols/isolation & purification , Signal Transduction/genetics
10.
Materials (Basel) ; 14(1)2020 Dec 31.
Article in English | MEDLINE | ID: mdl-33396469

ABSTRACT

The unique properties that nanoparticles exhibit, due to their small size, are the principal reason for their numerous applications, but at the same time, this might be a massive menace to the environment. The number of studies that assess the possible ecotoxicity of nanomaterials has been increasing over the last decade to determine if, despite the positive aspects, they should be considered a potential health risk. To evaluate their potential toxicity, models are used in all types of organisms, from unicellular bacteria to complex animal species. In order to better understand the environmental consequences of nanotechnology, this literature review aims to describe and classify nanoparticles, evaluating their life cycle, their environmental releasing capacity and the type of impact, particularly on living beings, highlighting the need to develop more severe and detailed legislation. Due to their diversity, nanoparticles will be discussed in generic terms focusing on the impact of a great variety of them, highlighting the most interesting ones for the industry.

11.
Acta Reumatol Port ; 44(3): 244-249, 2019.
Article in English | MEDLINE | ID: mdl-31575841

ABSTRACT

OBJECTIVE: The objective of this study is to evaluate the effectiveness of autohemotherapy with ozone in the management of fibromyalgia (FM). DESIGN: 20 FM patients (according to the criteria of the American College of Rheumatology), were treated with 10 sessions of ozone hemotherapy (2 sessions per week) with a concentration of 30-60 mcgr/ml. The health condition of the patients was evaluated before and after treatment, through the Fibromyalgia Impact Questionnaire (FIQ). Blood samples were obtained from all patients by venous puncture for biochemical routine analysis and serotonin levels in serum and the following peripheral blood mononuclear cells (BMCs) were isolated for oxidative stress quantification: reactive oxygen species (ROS) generation, and lipid peroxidation (LP) and protein carbonyl (PC) content, as these are signs of oxidative cell damage. RESULTS: All patients treated with ozone reported an improvement in sleep and mental alertness, a marked decrease of asthenia accompanied by a decrease of FIQ as well as tender points, and a moderate increase of serotonin levels. Also, an important decrease of LP and PC was observed; ROS also decreased, although less obvious, which indicates a reduction in oxidative stress levels. CONCLUSIONS: The autohemotherapy with ozone in patients with FM showed an important decline of tender points and FIQ score, as well as a decrease of oxidative stress levels. This treatment allows patients to face life with greater vitality and less drug use, diminishing harmful side effects. Further investigation should be carried out, including groups with more patients and clinical trials, to elucidate the effect of ozone therapy in patients suffering from FM.


Subject(s)
Blood Transfusion, Autologous , Blood/drug effects , Fibromyalgia/therapy , Ozone/administration & dosage , Adult , Biological Therapy/methods , Diagnostic Self Evaluation , Female , Humans , Middle Aged , Ozone/pharmacology , Sickness Impact Profile , Treatment Outcome
12.
Horiz. enferm ; 30(2): 171-204, 2019. tab, ilus
Article in Spanish | LILACS, BDENF - Nursing | ID: biblio-1223360

ABSTRACT

OBJETIVO: contribuir al empoderamiento de las mujeres jefas de hogar pertenecientes a una comunidad de un sector económicamente vulnerable de la ciudad de Santiago, por medio de la entrega de herramientas y habilidades en salud. Muestra: 13 mujeres, entre 22 y 55 años. METODOLOGÍA: Intervención educativa basada en el Modelo 'Comunidad como Socio' de Anderson y McFarlane de Enfermería y el Modelo de Educación para Adultos de Jane Vella. Se respondió una encuesta anónima para recopilar información. El diagnóstico participativo permitió identificar temas a tratar: control de signos vitales y su aplicabilidad, y atención de primeros auxilios. RESULTADOS: Se aportó al conocimiento del manejo de cuidados básicos en salud (Signos Vitales, Primeros Auxilios y Hábitos de Vida Saludable) aplicados a su autocuidado y al de sus familias. Se practicó lo aprendido en un escenario simulado. CONCLUSIÓN: Se identificaron fortalezas, como motivación por el aprendizaje y buena recepción de las metodologías participativas. La intervención contribuyó al empoderamiento de las participantes mediante el aprendizaje de contenidos, otorgando seguridad para enfrentar situaciones de emergencia en su vida cotidiana.


OBJECTIVE: Contribute the empowerment of female heads of household belonging to a community of an economically vulnerable sector of the city of Santiago, through the delivery of tools and skills in health. Sample: 13 women, between 22 and 55 years old. METHODOLOGY: Educational intervention based on the "Community as a Partner" Model of Anderson and McFarlane of Nursing and the Adult Education Model of Jane Vella. A survey was answered anonymously to collect information. The participatory diagnosis allowed identifications of thetopics concerned including: control of vital signs and its applications and first aid attention demonstrated practically in the sessions. RESULTS: Contributions were made to the knowledge regarding the management of basic care in health (Vital Signs, First Aid and Habits of Healthy Living) applied to self-care of patients and their respective families. In a simulated scenario, participants in the survey demonstrated that they practiced what they had learned. CONCLUSION: Strengths such as motivation for learning and positive response to participative methodologies were identified. Additionally, the intervention contributed to the empowerment of the participants through the learning of contents and development of confidence to confront emergency situations in every day life.


Subject(s)
Humans , Female , Adult , Middle Aged , Primary Health Care , Public Health , Empowerment , Self Care , Chile , Surveys and Questionnaires
13.
Eur J Pharmacol ; 797: 75-82, 2017 Feb 15.
Article in English | MEDLINE | ID: mdl-28099869

ABSTRACT

Amitriptyline, a tricyclic antidepressant, has been proposed as an antitumoral drug in oxidative therapy. Its pro-apoptotic effects, mediated by high reactive oxygen species generation, have been already described. In this study we analysed the effect of amitriptyline on the biosynthesis of coenzyme Q10 (CoQ), an essential component for electron transport and a potent membrane antioxidant involved in redox signaling. We treated H460 cells, a non-small-cell lung cancer cell line, with amitriptyline and we analysed CoQ levels by HPLC and CoQ biosynthesis rate, as well as the enzymes involved in CoQ biosynthesis by real-time PCR and Western blot. Amitriptyline treatment induced a dose-dependent decrease in CoQ levels in tumor cells. CoQ decreased levels were associated with down-regulation of the expression of COQ4 gene, as well as decreased Coq4 and Coq6 protein levels. Our findings suggest that the effect of amitriptyline on CoQ biosynthesis highlights the potential of this drug for antitumoral oxidative therapy.


Subject(s)
Amitriptyline/pharmacology , Lung Neoplasms/pathology , Ubiquinone/analogs & derivatives , Cell Line, Tumor , Dose-Response Relationship, Drug , Humans , Kinetics , Reactive Oxygen Species/metabolism , Ubiquinone/biosynthesis , Ubiquinone/metabolism
14.
J Pediatr Endocrinol Metab ; 29(6): 731-6, 2016 Jun 01.
Article in English | MEDLINE | ID: mdl-27054593

ABSTRACT

BACKGROUND: In this study, our aim was to analyze bone mineral density (BMD) in patients with type 1 diabetes mellitus (T1DM) and compare them with a healthy reference population; in addition, we aimed to observe the association between BMD and the following variables: age at onset, disease duration, metabolic control, pubertal stage, level of physical activity, clinical parameters and nutrient intake. METHODS: A total of 30 patients with T1DM were included in the study. BMD was determined using dual-energy X-ray densitometry (DXA). Participants with a z-score of values ≥-1 were accepted as normal; BMDs between -2 and -1 were defined as being in the low range of normality; ≤-2 were defined as having low BMD. The 25-hydroxy vitamin D level was classified as sufficient (30-100 ng/mL), insufficient (20-30 ng/mL), and deficient (<20 ng/mL). RESULTS: The percentages of patients with deficient and insufficient 25(OH) vitamin D levels were 50% and 45.8%, respectively. Lumbar spine (LS2-LS4) BMD, total body (TB) BMD and femoral neck (FN) BMD were found in the normal range for more than 80% of the subjects, with no significant differences due to gender. No strong correlations between clinical variables, biochemical parameters and nutrient intake were observed; however, a moderate positive correlation was found between serum calcium and LS2-LS4 BMD (p<0.05). Regression analysis showed that serum calcium, duration of diabetes and intake of sodium and protein are significant factors in determining LS2-LS4 BMD and TB BMD. CONCLUSIONS: Patients with T1DM had a normal mean BMD at all sites evaluated, except for two patients who had low BMD at the lumbar spine. More than 95% of patients had insufficient or deficient vitamin D levels. With respect to all the variables studied, serum calcium presented the highest significant correlation with LS2-LS4 BMD.


Subject(s)
Bone Density , Diabetes Mellitus, Type 1/metabolism , Adolescent , Adult , Child , Female , Humans , Male , Vitamin D/analogs & derivatives , Vitamin D/blood
15.
J Pediatr Endocrinol Metab ; 28(7-8): 895-902, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25781527

ABSTRACT

OBJECTIVE: The aim of this study was to assess dietary intake, nutritional status, body composition, and physical activity level in a group of Chilean children and adolescents with Type 1 diabetes mellitus (T1DM), compare these parameters with the recommendations of the International Society for Pediatric and Adolescent Diabetes (ISPAD), and determine the relationships between dietary intake, body composition, and diabetes control. METHODS: A total of 30 patients with T1DM (aged 15.2±4.0 years) were included. Dietary intake was assessed using a 92-item quantitative food frequency questionnaire. Body composition was determined using dual-energy X-ray densitometry. Physical activity was assessed by means of a survey. RESULTS: The energy intake of these patients was derived from 21.4% protein, 48% carbohydrates, and 31.2% fat. The glycosylated hemoglobin (HbA1c) was significantly correlated with fat as grams per day (r: 0.363, p<0.05) and calories per day (r: 0.364, p<0.05). The mean body fat percentage in females was 31.2% and 20.2% in males (p < 0.01) and the mean amount of physical activity was 4.5±2.7 h per week. CONCLUSIONS: The study patients had a higher protein intake than recommended by ISPAD. Dietary carbohydrate intake was rather low, and dietary fat intake was the same as the limits recommended by ISPAD. Diabetic control was significantly correlated with protein, carbohydrates, fat, and sodium intake. The girls in the study had a higher percentage of body fat than the standard recommendations for their age. The level of physical activity was adequate.


Subject(s)
Body Composition , Diabetes Mellitus, Type 1/physiopathology , Diet , Exercise/physiology , Adolescent , Adult , Blood Glucose/analysis , Body Mass Index , Child , Chile , Energy Intake , Female , Follow-Up Studies , Glycated Hemoglobin/analysis , Humans , Male , Prognosis , Young Adult
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