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1.
Crit Rev Clin Lab Sci ; 58(3): 207-224, 2021 05.
Article in English | MEDLINE | ID: mdl-33929278

ABSTRACT

In the clinical laboratory, knowledge of and the correct use of clot activators and anticoagulant additives are critical to preserve and maintain samples in optimal conditions prior to analysis. In 2017, the Latin America Confederation of Clinical Biochemistry (COLABIOCLI) commissioned the Latin American Working Group for Preanalytical Phase (WG-PRE-LATAM) to study preanalytical variability and establish guidelines for preanalytical procedures to be applied by clinical laboratories and health care professionals. The aim of this critical review, on behalf of COLABIOCLI WG-PRE-LATAM, is to provide information to understand the mechanisms of the interactions and reactions that occur between blood and clot activators and anticoagulant additives inside evacuated tubes used for laboratory testing. Clot activators - glass, silica, kaolin, bentonite, and diatomaceous earth - work by surface dependent mechanism whereas extrinsic biomolecules - thrombin, snake venoms, ellagic acid, and thromboplastin - start in vitro coagulation when added to blood. Few manufacturers of evacuated tubes state the type and concentration of clot activators used in their products. With respect to anticoagulant additives, sodium citrate and oxalate complex free calcium and ethylenediaminetetraacetic acid chelates calcium. Heparin potentiates antithrombin and hirudin binds to active thrombin, inactivating the thrombin irreversibly. Blood collection tubes have improved continually over the years, from the glass tubes containing clot activators or anticoagulant additives that were prepared by laboratory personnel to the current standardized evacuated systems that permit more precise blood/additive ratios. Each clot activator and anticoagulant additive demonstrates specific functionality, and both manufacturers of tubes and laboratory professional strive to provide suitable interference-free sample matrices for laboratory testing. Both manufacturers of in vitro diagnostic devices and laboratory professionals need to understand all aspects of venous blood sampling so that they do not underestimate the impact of tube additives on laboratory testing.


Subject(s)
Anticoagulants , Blood Specimen Collection , Anticoagulants/pharmacology , Blood Coagulation , Humans , Phlebotomy
2.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 29(4): 209-212, jul.-ago. 2018. ilus
Article in English | IBECS | ID: ibc-180311

ABSTRACT

Cervical Traumatic SSH are very rare in literature. They are usually caused by cardiopulmonary diseases that increase vascular pressure causing spinal vessels rupture. In thoracolumbar spine, the spinal puncture is the most common cause. The ventrolateral position is even more unusual. In traumatic brain injury (TBI), an abrupt extension-flexion movement could have caused the rupture of subarachnoid vessels. This, accompanied by the slowed blood "wash out" (probably due to the previous osteoarthrosis and spinal canal stenosis), led to the formation of an organized clot, which caused an acute spinal cord compression syndrome. Cervical subarachnoid spinal hematoma can present as Brown-Séquard syndrome. The treatment is prompt surgical removal and decompression. The posterior approach (partial hemilaminectomy with or without laminoplasty) with microsurgical technique is feasible, fast and simple to evacuate the hematoma with good results. Surgical nuances in posterior approach are: small spinal canal, difficulty in mobilizing the cervical cord, these haematomas are wrapped and attached to the spinal cord or nerve roots by multiple arachnoid bands, requiring techniques of Microdissection for its evacuation unlike the epidural and subdural haematomas that are easily aspirated. Here, we report a unique case of a ventrolateral SSH due to TBI


Los hematomas subaracnoideos espinales cervicales postraumáticos son muy infrecuentes en la literatura. Generalmente son causados por enfermedades cardiopulmonares que incrementan la presión vascular y producen la rotura de los vasos espinales. En la columna toracolumbar la causa más frecuente es la punción lumbar. La posición ventrolateral dentro del canal es todavía más inusual. En el traumatismo craneoencefálico, un movimiento súbito de flexoextensión podría causar la rotura de vasos subaracnoideos. Si lo anterior se acompaña de un «lavado» enlentecido de la sangre (probablemente debido a la presencia de osteoartrosis y estenosis de canal), podría llevar a la formación de un coágulo organizado, el cual, si es de gran tamaño, podría causar un síndrome de compresión medular aguda. Los hematomas subaracnoideos espinales cervicales pueden presentarse como un síndrome de Brown-Séquard. El tratamiento en caso de compresión medular aguda es la evacuación del coágulo y la descompresión del canal urgente. El abordaje posterior (hemilaminectomía parcial con o sin laminoplastia) con técnica microquirúrgica es factible, rápido y sencillo para evacuar el hematoma, con buenos resultados. Los matices quirúrgicos en el abordaje posterior son: pequeño canal espinal y dificultad para movilizar la médula cervical. Estos hematomas están envueltos y adheridos a la médula espinal o a las raíces nerviosas por múltiples bandas aracnoideas, requiriendo técnicas de microdisección para su evacuación, a diferencia de los hematomas epidurales y subdurales, que son fácilmente aspirados. Presentamos un caso único de un hematoma subaracnoideo espinal cervical ventrolateral debido a traumatismo craneoencefálico leve


Subject(s)
Humans , Female , Aged, 80 and over , Brown-Sequard Syndrome/etiology , Hematoma/complications , Subarachnoid Hemorrhage/complications , Spinal Cord Injuries/complications , Spinal Cord Compression/complications , Cervical Vertebrae
3.
Appl Microbiol Biotechnol ; 102(9): 3865-3878, 2018 May.
Article in English | MEDLINE | ID: mdl-29520602

ABSTRACT

In recent years, (bio)electrochemical systems (B)ES have emerged as an energy efficient alternative for the recovery of TAN (total ammonia nitrogen, including ammonia and ammonium) from wastewater. In these systems, TAN is removed or concentrated from the wastewater under the influence of an electrical current and transported to the cathode. Subsequently, it can be removed or recovered through stripping, chemisorption, or forward osmosis. A crucial parameter that determines the energy required to recover TAN is the load ratio: the ratio between TAN loading and applied current. For electrochemical TAN recovery, an energy input is required, while in bioelectrochemical recovery, electric energy can be recovered together with TAN. Bioelectrochemical recovery relies on the microbial oxidation of COD for the production of electrons, which drives TAN transport. Here, the state-of-the-art of (bio)electrochemical TAN recovery is described, the performance of (B)ES for TAN recovery is analyzed, the potential of different wastewaters for BES-based TAN recovery is evaluated, the microorganisms found on bioanodes that treat wastewater high in TAN are reported, and the toxic effect of the typical conditions in such systems (e.g., high pH, TAN, and salt concentrations) are described. For future application, toxicity effects for electrochemically active bacteria need better understanding, and the technologies need to be demonstrated on larger scale.


Subject(s)
Ammonium Compounds/isolation & purification , Electrochemistry , Water Purification , Ammonia/isolation & purification , Bacteria/metabolism , Electrodes , Oxidation-Reduction , Wastewater/chemistry , Wastewater/microbiology
4.
Rev. Asoc. Esp. Neuropsiquiatr ; 37(132): 415-437, jul.-dic. 2017.
Article in Spanish | IBECS | ID: ibc-169249

ABSTRACT

En el presente artículo, los autores examinan la fiabilidad y validez de un instrumento que, habiéndose utilizado en otras poblaciones, se consideró de especial interés para las personas con trastorno mental grave. La Escala Multidimensional de Apoyo Social Percibido (EMAS) podría resultar útil para la planificación y aplicación de estrategias de intervención sobre las redes sociales de este colectivo, teniendo en cuenta su percepción de los apoyos sociales. Para poner a prueba esta hipótesis, se seleccionaron tres dispositivos de Rehabilitación Psicosocial para personas con trastorno mental grave de la Comunidad de Madrid. Se reclutó una muestra de 59 personas. Los sujetos fueron evaluados con la EMAS. Las propiedades psicométricas que encontramos muestran que la EMAS es una herramienta óptima para guiar las intervenciones dirigidas a incrementar la percepción de los apoyos recibidos procedentes de amigos, familia y otras personas relevantes (AU)


In the present article, the authors examine the reliability and validity of an instrument that, having previously been used in other populations, was considered to be of special interest for people with severe mental disorders. The Multidimensional Scale of Perceived Social Support (MSPSS) might be useful for the planning and implementation of intervention strategies on the social networks of this collective, taking into account their perception of social support. In order to test this hypothesis, we selected three centers of psychosocial rehabilitation for this population in the Community of Madrid (Spain). A sample of 59 people with severe mental disorder was recruited. Subjects were assessed with the MSPSS. The psychometric properties we found show that the MSPSS is an optimal tool for guiding interventions aimed at increasing the perception of support received from relatives, friends, and significant others (AU)


Subject(s)
Humans , Social Support , Mental Disorders/psychology , Psychometrics/methods , Reproducibility of Results , Reproducibility of Results , Evaluation of the Efficacy-Effectiveness of Interventions , Social Networking , Mental Disorders/rehabilitation , Interpersonal Relations , Friends , Social Perception
5.
Int J Occup Environ Health ; 23(1): 40-51, 2017 01.
Article in English | MEDLINE | ID: mdl-29082831

ABSTRACT

Work stress is a major contributor to absenteeism and reduced work productivity. A randomised and controlled study in employee-volunteers (with Perceived Stress Scale [PSS-14]>22) was performed to assess a mindfulness program based on brief integrated mindfulness practices (M-PBI) with the aim of reducing stress in the workplace. The PSS-14 of the employees before and after 8-weeks M-PBI program, as well as after a 20-week follow-up, was assessed (primary endpoint). The employees also carried the following questionnaires (secondary endpoints): Five Facet Mindfulness Questionnaire (FFMQ), Self-Compassion Scale (SCS), Experiences Questionnaire-Decentering (EQ-D), and Maslach Burnout Inventory-General Survey (MBI-GS). Heart Rate Variability (HRV) was measured during each session in a subgroup of employees (n = 10) of the interventional group randomly selected. A total of 40 employees (77.5% female median [SD] age of 36.6 [5.6] years) took part in this study: 21 and 19 in the intervention and control group, respectively. No differences in baseline characteristics were encountered between the groups. Results show a significant decrease in stress and increase in mindfulness over time in the intervention group (PSS-14 and FFMQ; p < 0.05 both). Additionally, an improvement in decentering (EQ-D), self-compassion (SCS) and burnout (MBI-GS) were also observed compared to the control group (p < 0.05 in all). HRV measurement also showed an improvement. In conclusion, a brief practices, 8-weeks M-BIP program is an effective tool to quickly reduce stress and improve well-being in a workplace.


Subject(s)
Mindfulness/education , Occupational Stress/prevention & control , Occupational Stress/therapy , Workplace , Adult , Burnout, Professional/prevention & control , Burnout, Professional/therapy , Female , Heart Rate , Humans , Male , Pilot Projects , Self Report , Surveys and Questionnaires
6.
J Nutr Health Aging ; 21(1): 92-104, 2017.
Article in English | MEDLINE | ID: mdl-27999855

ABSTRACT

The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups' new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).


Subject(s)
Aging , Health Behavior , White People , Accidental Falls/prevention & control , Aged , Aged, 80 and over , Chronic Disease , Cooperative Behavior , Europe , Frail Elderly , Humans , Multiple Chronic Conditions , Organizational Innovation , Polypharmacy , Surveys and Questionnaires
7.
J Med Syst ; 39(9): 98, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26254254

ABSTRACT

Successful management of health conditions in older population is determined by strategic involvement of a professional team of careers and by empowering patients and their caregivers to take over a central role and responsibility in the daily management of condition. Identifying, structuring and ranking the most important needs related to these aspects could pave the way for improved strategies in designing systems and technological solutions supporting user empowerment. This paper presents the preliminary results of a study aiming to elicit these needs. Healthcare professionals, working together in the European and Innovation Partnership on Active and Healthy Ageing (EIP-AHA) initiative, have defined a set of needs and factors that have been organized in two hierarchies around the concepts of patient activation and proactive and prepared care team, defined in the Chronic Care Model. The two hierarchies have been mapped, by a team of experts in computer science, with technologies and solutions that could facilitate the achievement of the identified needs.


Subject(s)
Aging , Health Education/methods , Health Knowledge, Attitudes, Practice , Patient Participation/methods , Power, Psychological , Humans , Patient Care Team/organization & administration , Patient Participation/psychology
8.
Med Biol Eng Comput ; 53(12): 1333-43, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26049412

ABSTRACT

The present work presents the comparative assessment of four glucose prediction models for patients with type 1 diabetes mellitus (T1DM) using data from sensors monitoring blood glucose concentration. The four models are based on a feedforward neural network (FNN), a self-organizing map (SOM), a neuro-fuzzy network with wavelets as activation functions (WFNN), and a linear regression model (LRM), respectively. For the development and evaluation of the models, data from 10 patients with T1DM for a 6-day observation period have been used. The models' predictive performance is evaluated considering a 30-, 60- and 120-min prediction horizon, using both mathematical and clinical criteria. Furthermore, the addition of input data from sensors monitoring physical activity is considered and its effect on the models' predictive performance is investigated. The continuous glucose-error grid analysis indicates that the models' predictive performance benefits mainly in the hypoglycemic range when additional information related to physical activity is fed into the models. The obtained results demonstrate the superiority of SOM over FNN, WFNN, and LRM with SOM leading to better predictive performance in terms of both mathematical and clinical evaluation criteria.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 1/blood , Models, Statistical , Monitoring, Physiologic , Neural Networks, Computer , Adult , Female , Humans , Male , Middle Aged
9.
J Diabetes Res ; 2014: 710370, 2014.
Article in English | MEDLINE | ID: mdl-25215305

ABSTRACT

AIM: To study the evolution of impaired fasting glucose (IFG), considering glucose and HbA1c levels and risk factors associated, in a period of 6 years. METHODS: We studied 94 subjects with impaired fasting glucose (IFG) that were diagnosed in 2005 and followed up to 2012. Glucose and HbA1c levels were determined. A descriptive analysis of contingence charts was performed in order to study the evolution in the development of type-2 diabetes mellitus (T2DM). RESULTS: Twenty-eight of ninety-four subjects became T2DM; 51/94 remained with IFG; and 20/94 presented normal fasting glucose. From the 28 diabetic subjects, 9 had already developed diabetes and were under treatment with oral hypoglycemic agents; 5 were diagnosed with plasma glucose < 126 mg/dL, but with HbA1c over 6.5%. In those who developed diabetes, 15/28 had a family history of T2DM in first relative degree. Also, diabetic subjects had a BMI significantly higher than nodiabetics (t test: P < 0.01). The individuals that in 2005 had the highest BMI are those who currently have diabetes. CONCLUSION: The IFG constitutes a condition of high risk of developing T2DM in a few years, especially over 110 mg/dL and in obesity patients.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Fasting/blood , Glucose Metabolism Disorders/blood , Administration, Oral , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Body Mass Index , Chile/epidemiology , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/genetics , Disease Progression , Female , Follow-Up Studies , Genetic Predisposition to Disease , Glucose Metabolism Disorders/diagnosis , Glucose Metabolism Disorders/drug therapy , Glucose Metabolism Disorders/epidemiology , Glucose Metabolism Disorders/genetics , Glycated Hemoglobin/metabolism , Humans , Hypoglycemic Agents/administration & dosage , Male , Middle Aged , Obesity/diagnosis , Obesity/epidemiology , Pedigree , Risk Factors , Time Factors
10.
Nanoscale ; 6(21): 12905-11, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25230928

ABSTRACT

In this work we present core-shell nanowire arrays of gold coated with a nanometric layer of cobalt. Despite the extremely small Co volume, these core-shell nanowires display large magneto-optical activity and plasmonic resonance determined by the geometry of the structure. Therefore, we are able to tune both the plasmonic and magneto-optical response in the visible range. Through optical and ellipsometric measurements in transmission, and applying a magnetic field to the sample, it is possible to modulate the value of the phase angle (Del {Δ}) between the S and P polarised components. It was found that the core-shell sample produced an order of magnitude larger variation in Del with changing magnetic field direction, compared with hollow cobalt tubes. The enhancement of magneto optical properties through the plasmonic nature of the gold core is complemented with the ability to induce magnetic influence over optical properties via an externally applied field. Moreover, we demonstrate for the first time the ability to use the remanent magnetisation of the Co, in conjunction with the optical properties defined by the Au, to observe remanent optical states in this uniquely designed structure. This new class of magnetoplasmonic metamaterial has great potential in a wide range of applications, from bio-sensing to data storage due to the tuneable nature of multiple resonance modes and dual functionality.

11.
Biol Trace Elem Res ; 158(3): 342-52, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24699828

ABSTRACT

Epidemiological studies have reported an association between high iron (Fe) levels and elevated risk of developing type 2 diabetes mellitus (T2D). It is believed that the formation of Fe-catalyzed hydroxyl radicals may contribute to the development of diabetes. Our goal was to determine the effect of a diet with a high Fe content on type 2 diabetic pigs. Four groups of piglets were studied: (1) control group, basal diet; (2) Fe group, basal diet with 3,000 ppm ferrous sulfate; (3) diabetic group (streptozotocin-induced type 2 diabetes) with basal diet; (4) diabetic/Fe group, diabetic animals/3,000 ppm ferrous sulfate. For 2 months, biochemical and hematological parameters were evaluated. Tissue samples of liver and duodenum were obtained to determine mRNA relative abundance of DMT1, ferroportin (Fpn), ferritin (Fn), hepcidin (Hpc), and transferrin receptor by qRT-PCR. Fe group presented increased levels of hematological (erythrocytes, hematocrit, and hemoglobin) and iron parameters. Diabetic/Fe group showed similar behavior as Fe group but in lesser extent. The relative abundance of different genes in the four study groups yielded a different expression pattern. DMT1 showed a lower expression in the two iron groups compared with control and diabetic animals, and Hpc showed an increased on its expression in Fe and diabetic/Fe groups. Diabetic/Fe group presents greater expression of Fn and Fpn. These results suggest that there is an interaction between Fe nutrition, inflammation, and oxidative stress in the diabetes development.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Iron Overload/metabolism , Iron, Dietary/metabolism , Analysis of Variance , Animals , Blood Glucose/metabolism , C-Reactive Protein/metabolism , Cation Transport Proteins/genetics , Cholesterol/blood , Cholesterol, LDL/blood , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/genetics , Diet , Duodenum/drug effects , Duodenum/metabolism , Ferritins/genetics , Ferrous Compounds/administration & dosage , Ferrous Compounds/metabolism , Gene Expression/drug effects , Hepcidins/genetics , Iron Overload/physiopathology , Iron, Dietary/administration & dosage , Liver/drug effects , Liver/metabolism , Male , Receptors, Transferrin/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sus scrofa , Time Factors , Triglycerides/blood
12.
Biol Trace Elem Res ; 158(1): 122-7, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24531910

ABSTRACT

Calcium, phytic acid, polyphenols and fiber are major inhibitors of iron absorption and they could be found in excess in some diets, thereby altering or modifying the iron nutrition status. The purpose of this study is to evaluate the effect of calcium, tannic acid, phytic acid, and pectin over iron uptake, using an in vitro model of epithelial cells (Caco-2 cell line). Caco-2 cells were incubated with iron (10-30 µM) with or without CaCl2 (500 and 1,000 µM) for 24 h. Then, cells were challenged with phytic acid (50-150 µM); pectin (50-150 nM) or tannic acid (100-500 µM) for another 24 h. Finally, (55)Fe (10 µM) uptake was determined. Iron dialyzability was studied using an in vitro digestion method. Iron uptake in cells pre-incubated with 20 and 30 µM Fe was inhibited by CaCl2 (500 µM). Iron uptake decreased in cells cultured with tannic acid (300 µM) and CaCl2 (500-1,000 µM) (two-way ANOVA, p = 0.002). Phytic acid also decreased iron uptake mainly when cells were treated with CaCl2 (1,000 µM) (two-way ANOVA; p < 0.05). Pectin slightly decreased iron uptake (p = NS). Iron dialyzability decreased when iron was mixed with CaCl2 and phytic or tannic acid (T test p < 0.0001, for both) but not when mixed with pectin. Phytic acid combined with calcium is a strong iron uptake inhibitor. Pectin slightly decreased iron uptake with or without calcium. Tannic acid showed an unexpected behavior, inducing an increase on iron uptake, despite its low Fe dialyzability.


Subject(s)
Calcium/pharmacology , Iron/pharmacokinetics , Pectins/pharmacology , Phytic Acid/pharmacology , Tannins/pharmacology , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Analysis of Variance , Caco-2 Cells , Calcium Chloride/pharmacology , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Dose-Response Relationship, Drug , Humans , Intestinal Absorption/drug effects , Iron/pharmacology , Models, Biological
13.
Adv Funct Mater ; 24(20): 2993-3002, 2014 May.
Article in English | MEDLINE | ID: mdl-25844085

ABSTRACT

Recently, lead iron tantalate/lead zirconium titanate (PZTFT) was demonstrated to possess large, but unreliable, magnetoelectric coupling at room temperature. Such large coupling would be desirable for device applications but reproducibility would also be critical. To better understand the coupling, the properties of all 3 ferroic order parameters, elastic, electric, and magnetic, believed to be present in the material across a range of temperatures, are investigated. In high temperature elastic data, an anomaly is observed at the orthorhombic mm2 to tetragonal 4mm transition, Tot = 475 K, and a softening trend is observed as the temperature is increased toward 1300 K, where the material is known to become cubic. Thermal degradation makes it impossible to measure elastic behavior up to this temperature, however. In the low temperature region, there are elastic anomalies near ≈40 K and in the range 160-245 K. The former is interpreted as being due to a magnetic ordering transition and the latter is interpreted as a hysteretic regime of mixed rhombohedral and orthorhombic structures. Electrical and magnetic data collected below room temperature show anomalies at remarkably similar temperature ranges to the elastic data. These observations are used to suggest that the three order parameters in PZTFT are strongly coupled.

14.
Nat Commun ; 4: 1534, 2013.
Article in English | MEDLINE | ID: mdl-23443562

ABSTRACT

Single-phase magnetoelectric multiferroics are ferroelectric materials that display some form of magnetism. In addition, magnetic and ferroelectric order parameters are not independent of one another. Thus, the application of either an electric or magnetic field simultaneously alters both the electrical dipole configuration and the magnetic state of the material. The technological possibilities that could arise from magnetoelectric multiferroics are considerable and a range of functional devices has already been envisioned. Realising these devices, however, requires coupling effects to be significant and to occur at room temperature. Although such characteristics can be created in piezoelectric-magnetostrictive composites, to date they have only been weakly evident in single-phase multiferroics. Here in a newly discovered room temperature multiferroic, we demonstrate significant room temperature coupling by monitoring changes in ferroelectric domain patterns induced by magnetic fields. An order of magnitude estimate of the effective coupling coefficient suggests a value of ~1 × 10(-7) sm(-1).

15.
Biosens Bioelectron ; 41: 862-6, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-22964383

ABSTRACT

The medical diagnostic, the industry, and the biotechnology require rapid, sensitive, and easy to use methods for trypsin activity determination. A simple approach, which meets all these requirements, based on Quartz Crystal Microbalance (QCM) was developed, analytically characterized and described in the present work. QCM application allows rapid trypsin activity evaluation by real time monitoring of the enzymatic degradation of the substrate. The new approach suggested in this work takes advantage of nanoparticles loaded gelatin employment as a trypsin substrate, deposited on the QCM crystal. The heavy nanoparticles leave the substrate layer together with the products of its enzymatic degradation provoking thus a greater decrease of the total QCM crystal mass compared with the non charged substrate. As a result, a higher sensor frequency response occurs. A 10 fold improvement of the LOD was achieved for trypsin activity evaluation applying the proposed method with Ag nanoparticles loaded gelatin (7.5×10(-4) U mL(-1) vs. 7.5×10(-3) U mL(-1) obtained by the "classic" QCM method). The approach subject of this work can be applied with any substrate degrading enzyme.


Subject(s)
Biosensing Techniques/instrumentation , Micro-Electrical-Mechanical Systems/instrumentation , Nanoparticles/chemistry , Nanotechnology/instrumentation , Silver/chemistry , Trypsin/analysis , Trypsin/chemistry , Enzyme Activation , Equipment Design , Equipment Failure Analysis , Nanoparticles/ultrastructure , Reproducibility of Results , Sensitivity and Specificity
16.
Biometals ; 25(4): 749-59, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22476617

ABSTRACT

Adipose tissue secretes numerous pro-inflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α that can lead to insulin resistance (IR). In the liver, both IL-6 and TNF-α induce IR by inhibiting phosphorylation or ubiquitination of IRS1. In IR development, Fe is a risk factor in type-2 diabetes development. We studied the expression of genes related to inflammation, hypoxia, and mitochondrial function in hepatic (HepG2) and adipose (3T3-L1) cells. HepG2 and 3T3-L1 cells were incubated with 20 µM Fe, 40 µM Fe, or 40 µM Fe/20 mM glucose for 7 days and then challenged with 20 ng/ml IL-6 and/or 100 µM CoCl(2) for 20 h. We measured intracellular Fe levels and the relative expression of hepcidin, NF-κB, IL-6, TNF-α, hypoxia inducible factor 1α (HIF-1α), and mitofusin 2 (Mfn-2) mRNA using qRT-PCR. The intracellular Fe concentration in HepG2 cells did not change with 20 or 40 µM Fe. However, levels were decreased with Fe/glucose and IL-6 and/or CoCl(2). 3T3-L1 cells showed an increase in intracellular Fe with high Fe plus either IL-6 or CoCl(2). HepG2 cells incubated with 40 µM Fe alone or Fe/glucose and challenged with IL-6 and/or CoCl(2) showed increased IL-6, NF-κB, and TNF-α mRNA expression and decreased mRNA expression of Mfn-2 in all experimental conditions. 3T3-L1 cells incubated with 40 µM Fe alone or Fe/glucose and challenged with IL-6 showed increased NF-κB mRNA expression and decreased Mfn-2 expression in all experimental conditions. Thus, high Fe, inflammation, and hypoxia trigger the expression of genes related to inflammation and Fe metabolism in HepG2 cells, in 3T3-L1 cells the same stimuli increased NF-kB and hepcidin expression.


Subject(s)
Adipocytes/drug effects , Adipocytes/metabolism , Hepatocytes/drug effects , Hepatocytes/metabolism , Iron/pharmacology , 3T3-L1 Cells , Animals , Antimicrobial Cationic Peptides/metabolism , Cell Hypoxia/drug effects , Cell Hypoxia/genetics , Cobalt/pharmacology , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Hep G2 Cells , Hepcidins , Humans , Interleukin-6/pharmacology , Mice , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , NF-kappa B/genetics , Tumor Necrosis Factor-alpha/pharmacology
17.
Biol Trace Elem Res ; 149(1): 1-4, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22426798

ABSTRACT

This study aims to measure iron nutrition parameters and to determine the presence of anemia in obese type 2 diabetic patients and to analyze the mRNA relative abundance of genes related to inflammation, immune system, iron metabolism, and mitochondrial activity. Obese type 2 diabetic (OBDM, n=30) and healthy subjects (Cn, n=30) were studied. Biochemical, anthropometric, and iron nutrition parameters were determined. Peripheral mononuclear cells from type 2 diabetic and control group were challenged with high concentrations of iron (Fe) and glucose and total mRNA was isolated. The frequency of anemia among diabetic patients was 4/30. OBDM patients with or without anemia had higher levels of ferritin and high-sensitivity C-reactive protein than the Cn group. mRNA relative abundance of nuclear factor kappa-light-chain-enhancer of activated B cells was elevated in OBDM with anemia, and mRNA expression of interleukin-6 and toll-like receptor (TLR) 2 was increased in OBDM group in basal high Fe and high glucose concentrations. The expression of tumor necrosis factor alpha and TLR-4 was increased in OBDM with anemia in all experimental conditions. Hepcidin mRNA expression was increased in OBDM with anemia even in basal Fe concentration, and mitofusin 2 was decreased in all experimental conditions. This study shows that obese type 2 diabetic patients have iron distribution disorders associated to their proinflammatory state, and anemic subjects have a marked elevation of hepcidin mRNA expression.


Subject(s)
Anemia/blood , Antimicrobial Cationic Peptides/metabolism , Diabetes Mellitus, Type 2/blood , Ferritins/metabolism , Leukocytes, Mononuclear/metabolism , RNA, Messenger/metabolism , Adult , Anemia/complications , Anemia/genetics , Antimicrobial Cationic Peptides/genetics , Blood Glucose/metabolism , C-Reactive Protein/metabolism , Case-Control Studies , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/genetics , Ferritins/pharmacology , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Gene Expression Regulation , Glucose/metabolism , Glucose/pharmacology , Hepcidins , Humans , Inflammation/blood , Inflammation/genetics , Interleukin-6/genetics , Interleukin-6/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/pathology , Male , Middle Aged , Mitochondria/genetics , Mitochondria/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Obesity/blood , Obesity/genetics , RNA, Messenger/genetics , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/metabolism , Waist Circumference
18.
Rev. salud pública Parag ; 1(2): 19-25, Jul - Dic 2011.
Article in Spanish | LILACS | ID: biblio-965957

ABSTRACT

Este ensayo pretende mostrar algunas teorías de la justicia social y su relación con los servicios de salud. Destacándose dentro de las corrientes revisada la proporcional natural, libertad contractual, la igualdad social, y la de bienestar colectivo, las cuales de una u otra manera aportan a la reconfiguración de los servicios de salud. Si bien estas teorías no son las generadoras directas de sistemas de atención en salud que se denominen justos o injustos, si son de gran importancia pues de estas se derivan discusiones sobre justicia, equidad y libertad que permean la normatividad con que los representantes del Estado formulan y ponen en práctica dichos sistemas. Palabras clave: Sistemas de servicios de salud, Justicia social, Equidad


This paper aims to show some theories of social justice and its relation to health services. Emphasizing on the current proportional revised natural, contractual freedom, social equality and collective welfare, which in one way or another contribute to the reconfiguration of health services. While these theories are not the direct generation of health care systems that are denominated fair or not fair, if they are of great importance because these are derived from discussions about justice, fairness and freedom that permeate the regulations with which the representatives of the State made and implement such systems. Keywords: Health care systems, Social justice, Equity.


Subject(s)
Social Justice , Equity in Access to Health Services
19.
Nanotechnology ; 22(25): 254025, 2011 Jun 24.
Article in English | MEDLINE | ID: mdl-21572214

ABSTRACT

La(0.7)Sr(0.3)MnO(3)-SrRuO(3) superlattices with and without nanometrically thin SrTiO(3), BaTiO(3) and Ba(0.7)Sr(0.3)TiO(3) interlayers were grown by pulsed laser deposition. Transmission electron microscopy studies showed coherent growth of La(0.7)Sr(0.3)MnO(3), SrRuO(3) and SrTiO(3) layers with atomically sharp interfaces, even if individual layers were as thin as one or two unit cells. In contrast, misfit dislocations and unit cell high interfacial steps were observed at the interfaces between BaTiO(3) and one of the ferromagnetic layers. The presence of the interlayers as well as these extended defects had a significant influence on the magnetic properties of the superlattices, especially on the antiferromagnetic interlayer exchange coupling between the La(0.7)Sr(0.3)MnO(3) and SrRuO(3) layers and the exchange biasing. Surprisingly, exchange biasing was found to increase with decreasing strength of the antiferromagnetic interlayer exchange coupling. This was explained by different magnetization reversal mechanisms acting in the regimes of strong and weak interlayer exchange coupling.

20.
Eur J Nutr ; 50(5): 363-71, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21079975

ABSTRACT

BACKGROUND: Heme iron is found in the diet mainly in the form of hemoglobin and myoglobin. It is known that heme iron (heme-Fe) and inorganic iron are absorbed differently. Intracellularly, heme oxygenase-1 (HO1) participates in the cleavage of the heme ring producing biliverdin, CO and ferrous iron. Iron released from heme becomes part of labile iron pool, and it can be stored in ferritin or released through the basolateral membrane. The mechanism by which heme-Fe is metabolized within cells is not completely understood. OBJECTIVE: This study focused on the uptake and transport of heme iron and on the role of heme oxygenase-1 on heme iron metabolism. DESIGN: Caco-2 cells were incubated with different concentrations of heme-Fe. A full-length heme oxygenase-1 cDNA was expressed in Caco-2 cells and intracellular iron and heme-Fe content, heme uptake, heme and iron transport and heme oxygenase-1 immunolocalization were assessed in these cells. RESULTS: Heme-Fe was bioavailable and induced an intracellular increase in iron, ferritin and HO1 levels and a decrease in DMT1 expression. In cells overexpressing HO1, heme-Fe uptake and transepithelial Fe transport was higher than in controls. Most heme-Fe was metabolized to free iron, most of which was found mainly in the basolateral chamber. However, there is a fraction of heme that is delivered intact to the basolateral side. In a high heme-Fe condition, HO1 is found near the plasma membrane. CONCLUSIONS: These results suggest that heme oxygenase-1 catabolizes most of the heme-Fe and favors iron influx and efflux in intestinal cells.


Subject(s)
Heme Oxygenase-1/metabolism , Heme/pharmacokinetics , Iron/pharmacokinetics , Antibodies/analysis , Biological Availability , Biological Transport , Blotting, Western , Caco-2 Cells , Ferritins/genetics , Ferritins/metabolism , Gene Expression Regulation , Heme Oxygenase-1/genetics , Hemoglobins/metabolism , Humans , Intestinal Mucosa/metabolism , Intestines/cytology , Oxidoreductases Acting on CH-CH Group Donors/metabolism
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