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1.
Molecules ; 26(11)2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-34198893

RESUMEN

In this work, a low-cost and rapid electrochemical resistive DNA biosensor based on the current relaxation method is described. A DNA probe, complementary to the specific human papillomavirus type 16 (HPV-16) sequence, was immobilized onto a screen-printed gold electrode. DNA hybridization was detected by applying a potential step of 30 mV to the system, composed of an external capacitor and the modified electrode DNA/gold, for 750 µs and then relaxed back to the OCP, at which point the voltage and current discharging curves are registered for 25 ms. From the discharging curves, the potential and current relaxation were evaluated, and by using Ohm's law, the charge transfer resistance through the DNA-modified electrode was calculated. The presence of a complementary sequence was detected by the change in resistance when the ssDNA is transformed in dsDNA due to the hybridization event. The target DNA concentration was detected in the range of 5 to 20 nM. The results showed a good fit to the regression equation ΔRtotal(Ω)=2.99 × [DNA]+81.55, and a detection limit of 2.39 nM was obtained. As the sensing approach uses a direct current, the electronic architecture of the biosensor is simple and allows for the separation of faradic and nonfaradaic contributions. The simple electrochemical resistive biosensor reported here is a good candidate for the point-of-care diagnosis of HPV at a low cost and in a short detection time.


Asunto(s)
Técnicas Biosensibles/instrumentación , ADN Viral/análisis , Papillomavirus Humano 16/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Técnicas Electroquímicas/instrumentación , Electrodos , Oro/química , Papillomavirus Humano 16/genética , Humanos , Límite de Detección , Pruebas en el Punto de Atención
2.
Sensors (Basel) ; 19(18)2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31540232

RESUMEN

DNA electrochemical biosensors represent a feasible alternative for the diagnosis of different pathologies. In this work, the development of an electrochemical method for Human Papillomavirus-16 (HPV-16) sensing is reported based on potential relaxation measurements related to the discharge of a complex double layer of a DNA-modified gold electrode. The method used allows us to propose an equivalent circuit (EC) for a DNA/Au electrode, which was corroborated by electrochemical impedance spectroscopy (EIS) measurement. This model differs from the Randles circuit that is commonly used in double-layer simulations. The change in the potential relaxation and associated charge transfer resistance were used for sensing the DNA hybridization by using the redox pair Fe(CN)64-/Fe(CN)63+ as an electrochemical indicator. In order to determinate only the potential relaxation of the composed double layer, the faradic and double-layer current contributions were separated using a rectifier diode arrangement. A detection limit of 0.38 nM was obtained for the target HPV-16 DNA sequences. The biosensor showed a qualitative discrimination between a single-base mismatched sequence and the fully complementary HPV-16 DNA target. The results indicate that the discharge of the double-layer detection method can be used to develop an HPV DNA biosensor.


Asunto(s)
Técnicas Biosensibles/métodos , ADN Viral/análisis , Papillomavirus Humano 16/aislamiento & purificación , Secuencia de Bases , Electroquímica , Electrodos , Oxidación-Reducción
3.
Mol Genet Metab ; 117(2): 199-209, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26766614

RESUMEN

New enzyme delivery technologies are required for treatment of lysosomal storage disorders with significant pathologies associated with the so-called "hard-to-treat" tissues and organs. Genetic deficiencies in the GLB1 gene encoding acid ß-galactosidase lead to GM1-gangliosidosis or Morquio B, lysosomal diseases with predominant disease manifestation associated with the central nervous system or skeletal system, respectively. Current lysosomal ERTs are delivered into cells based on receptor-mediated endocytosis and do not effectively address several hard-to-treat organs including those critical for GM1-gangliosidosis patients. Lectins provide alternative cell-uptake mechanisms based on adsorptive-mediated endocytosis and thus may provide unique biodistribution for lysosomal disease therapeutics. In the current study, genetic fusions of the plant galactose/galactosamine-binding lectin, RTB, and the human acid ß-galactosidase enzyme were produced using a plant-based bioproduction platform. ß-gal:RTB and RTB:ß-gal fusion products retained both lectin activity and ß-galactosidase activity. Purified proteins representing both fusion orientations were efficiently taken up into GM1 patient fibroblasts and mediated the reduction of GM1 ganglioside substrate with activities matching mammalian cell-derived ß-galactosidase. In contrast, plant-derived ß-gal alone was enzymatically active but did not mediate uptake or correction indicating the need for either lectin-based (plant product) or mannose-6-phosphate-based (mammalian product) delivery. Native ß-galactosidase undergoes catalytic activation (cleavage within the C-terminal region) in lysosomes and is stabilized by association with protective protein/cathepsin A. Enzymatic activity and lysosomal protein processing of the RTB fusions were assessed following internalization into GM1 fibroblasts. Within 1-4h, both ß-gal:RTB and RTB:ß-gal were processed to the ~64kDa "activated" ß-gal form; the RTB lectin was cleaved and rapidly degraded. The activated ß-gal was still detected at 48h suggesting interactions with protective protein/cathepsin A. Uptake-saturation analyses indicated that the RTB adsorptive-mediated mechanisms of ß-gal:RTB supported significantly greater accumulation of ß-galactose activity in fibroblasts compared to the receptor-mediated mechanisms of the mammalian cell-derived ß-gal. These data demonstrate that plant-made ß-gal:RTB functions as an effective replacement enzyme for GM1-gangliosidosis - delivering enzyme into cells, enabling essential lysosomal processing, and mediating disease substrate clearance at the cellular level. RTB provides novel uptake behaviors and thus may provide new receptor-independent strategies that could broadly impact lysosomal disease treatments.


Asunto(s)
Gangliosidosis GM1/tratamiento farmacológico , Proteínas Recombinantes de Fusión/metabolismo , beta-Galactosidasa/metabolismo , Células Cultivadas , Terapia de Reemplazo Enzimático , Fibroblastos/enzimología , Humanos , Cinética , Lisosomas/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/genética , Lectinas de Plantas/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Nicotiana , beta-Galactosidasa/química , beta-Galactosidasa/genética
4.
Reumatol Clin (Engl Ed) ; 20(4): 223-225, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38644032

RESUMEN

Paraguay is currently facing a new outbreak of Chikungunya virus. This report summarizes two severe cases of Chikungunya (CHIKV) infection, confirmed by real-time reverse transcription polymerase chain reaction. We present the cases of patients with acute CHIKV infection and multisystem involvement, with fever, rash, abdominal pain, vomiting, myocarditis, and coronary artery anomalies, very similar to the cases described in MIS-C related to SARS-CoV-2 during the COVID-19 Pandemic. Both patients received IVIG and methylprednisolone, with good clinical response. In this setting of cytokine storm in Chikungunya, can we call it "Multisystem inflammatory syndrome associated with Chikungunya"?.


Asunto(s)
Fiebre Chikungunya , Síndrome de Liberación de Citoquinas , Síndrome de Respuesta Inflamatoria Sistémica , Humanos , Fiebre Chikungunya/complicaciones , Fiebre Chikungunya/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Masculino , Síndrome de Liberación de Citoquinas/etiología , Femenino , Adulto , Persona de Mediana Edad
5.
BMJ Open ; 13(2): e065628, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36792320

RESUMEN

INTRODUCTION: Stroke survivors usually experience long-lasting functional, emotional and social consequences that might contribute to sedentary behaviour and participation restrictions, which are important targets to address during rehabilitation. However, the trajectory and inter-relationship between these factors are unknown. METHODS AND ANALYSIS: Part&Sed is a research project based on an observational study design with 6 and 12 months of follow-ups in stroke survivors. In addition, a qualitative analysis of the impact of the stroke on the stroke survivor, validation of the Satisfaction with Daily Occupation-Occupational Balance assessment tool and analysis of the reliability of the Fitbit Inspire 2 activity tracker wristband will be carried out. Participants will be chronic stroke survivors with independent walking capacity. Sociodemographic and clinical data, physical activity, ambulation, sleep, quality of life, anxiety and depression, community participation, and occupational satisfaction and balance, as well as data provided by the activity tracker wristband, will be collected. In addition, if the participant has a primary caregiver, the caregiver will also be monitored. A minimum of 130 participants will be recruited to conduct a random-effects multiple regression model. Mixed models for repeated measures will assess the variation over time of the different variables associated with participation and sedentary behaviour. Psychometric properties (eg, internal consistency, construct validity, test-retest reliability) of the Satisfaction with Daily Occupation-Occupational Balance will be determined. Additionally, intraclass correlation coefficients and minimum detectable change will be calculated to assess intrasubject reliability of physical activity and sleep parameters recorded by the Fitbit Inspire 2. The qualitative analysis process will be carried out using the analysis proposed by Giorgi. ETHICS AND DISSEMINATION: The study received ethical approval from the Spanish Regional Ethics Committee 'Comité de Ética de la Investigación de la Comunidad de Aragón' (PI21/333). The results will be made available via peer-reviewed publications, international conferences and official channels.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Conducta Sedentaria , Calidad de Vida , Reproducibilidad de los Resultados , Rehabilitación de Accidente Cerebrovascular/métodos , Sobrevivientes/psicología , Estudios Observacionales como Asunto , Estudios Multicéntricos como Asunto
6.
Genes (Basel) ; 14(1)2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36672899

RESUMEN

(1) Background: obesity is a global public health problem; various factors have been associated with this disease, and genetic factors play a very important role. Previous studies in multiple populations have associated a gene with fat mass and obesity (FTO). Thus, the present work aims to identify and determine associations between genetic variants of FTO with indicators of overweight and obesity in the Mexican population. (2) Methods: a total of 638 subjects were evaluated to compile data on body mass index (BMI), the percentage of body fat (%BF), the waist circumference (WC), the serum levels of triglycerides (TG), and food consumption. A total of 175 genetic variants in the FTO gene were sampled by a microarray in the evaluated population, followed by association statistical analyses and comparisons of means. (3) Results: a total of 34 genetic variants were associated with any of the 6 indicators of overweight and obesity, but only 15 showed mean differences using the recessive model after the Bonferroni correction. The present study shows a wide evaluation of FTO genetic variants associated with a classic indicator of overweight and obesity, which highlights the importance of genetic analyses in the study of obesity.


Asunto(s)
Sobrepeso , Polimorfismo de Nucleótido Simple , Humanos , Sobrepeso/epidemiología , Sobrepeso/genética , Predisposición Genética a la Enfermedad , Obesidad/epidemiología , Obesidad/genética , Índice de Masa Corporal , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética
7.
J Am Board Fam Med ; 35(4): 686-694, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35896459

RESUMEN

INTRODUCTION: The COVID-19 global pandemic has affected all ethnic and minority groups although not equally. The goals of the present study are twofold: describe the diverse COVID-19-related care needs Hispanic patients presenting to a primary care facility and the symptom clusters and socioeconomic factors that may impact their wellbeing. METHODS: This is a retrospective cohort of Hispanic patients in an outpatient clinic serving an urban lower socioeconomic demographic, between May 9 and July 31, 2020. COVID-19 infection was confirmed by polymerase chain reaction or rapid antibody test. Student's t-test was used for means and the chi2 was used for comparisons of proportions. RESULTS: A total of 6616 patients visited Alivio, 409 were triaged to a containment area, and 378 were tested for COVID-19; 230 with, 148 without symptoms. Of those tested, 161(42.6%) were positive, representing 2.4% of total patients seen. Age, temperature, and pulse rate were all significantly higher in patients with symptoms compared with those without. Symptoms were grouped into 5 clusters: constitutional, n = 143(62%), respiratory, n = 136 (59%), and somatic, n = 97(42%) were most common. No single cluster was particularly diagnostic of COVID-19, although those with symptoms in multiple clusters were more likely to test positive, P < .001. The majority worked in essential jobs, were uninsured, and had more than half had prolonged symptoms. CONCLUSIONS: Hispanic patients have diverse reasons for seeking health care and for testing in a pandemic. COVID-19 is a syndromic disease as evidenced from the clustering of symptoms. Essential workers and uninsured health status may lead to more prolonged disease course.


Asunto(s)
COVID-19 , COVID-19/epidemiología , Hispánicos o Latinos , Humanos , Pandemias , Atención Primaria de Salud , Estudios Retrospectivos , SARS-CoV-2
8.
Cells ; 11(16)2022 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-36010656

RESUMEN

GM1-gangliosidosis is a catastrophic, neurodegenerative lysosomal storage disease caused by a deficiency of lysosomal ß-galactosidase (ß-Gal). The primary substrate of the enzyme is GM1-ganglioside (GM1), a sialylated glycosphingolipid abundant in nervous tissue. Patients with GM1-gangliosidosis present with massive and progressive accumulation of GM1 in the central nervous system (CNS), which leads to mental and motor decline, progressive neurodegeneration, and early death. No therapy is currently available for this lysosomal storage disease. Here, we describe a proof-of-concept preclinical study toward the development of enzyme replacement therapy (ERT) for GM1-gangliosidosis using a recombinant murine ß-Gal fused to the plant lectin subunit B of ricin (mß-Gal:RTB). We show that long-term, bi-weekly systemic injection of mß-Gal:RTB in the ß-Gal-/- mouse model resulted in widespread internalization of the enzyme by cells of visceral organs, with consequent restoration of enzyme activity. Most importantly, ß-Gal activity was detected in several brain regions. This was accompanied by a reduction of accumulated GM1, reversal of neuroinflammation, and decrease in the apoptotic marker caspase 3. These results indicate that the RTB lectin delivery module enhances both the CNS-biodistribution pattern and the therapeutic efficacy of the ß-Gal ERT, with the potential to translate to a clinical setting for the treatment of GM1-gangliosidosis.


Asunto(s)
Gangliósido G(M1) , Gangliosidosis GM1 , Animales , Sistema Nervioso Central/metabolismo , Terapia de Reemplazo Enzimático , Gangliosidosis GM1/tratamiento farmacológico , Gangliosidosis GM1/genética , Lectinas/uso terapéutico , Ratones , Distribución Tisular , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
9.
Proc Inst Mech Eng H ; 236(11): 1675-1684, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36177975

RESUMEN

A detailed numerical analysis is carried out in a real human thoracic aorta by means of the Computational Fluid Dynamics (CFD) for the prediction of the atherosclerosis lesion. Common hemodynamics parameters, such as, the oscillatory shear index (OSI) and the time average wall shear stress (TAWSS) are used for the prediction of the atherosclerosis lesion. Furthermore, the entropy generation rate is considered to obtain the main irreversibilities that occurs inside the thoracic aorta for the prediction of the atherosclerosis lesion. The model considers the blood flow inside the thoracic aorta in an unsteady state. The results show contours of velocity, streams lines, velocity profiles and the comparison of the hemodynamics parameters OSI versus TAWSS. Moreover, contours of the entropy generation rate are showed inside the aorta. The time averaged entropy generation rate (TAEGR) is obtained as a result of the entropy generation analysis. Finally, TAEGR index is compared and discussed with the common hemodynamics parameters, OSI and TAWSS. The accuracy to detect prone locations to atherosclerotic development in the real aorta using the TAEGR in comparison to the OSI and the TAWSS is in good agreement.


Asunto(s)
Aorta Torácica , Aterosclerosis , Humanos , Aorta Torácica/fisiología , Entropía , Hemodinámica/fisiología , Hidrodinámica , Estrés Mecánico , Modelos Cardiovasculares , Velocidad del Flujo Sanguíneo/fisiología
10.
Eur J Phys Rehabil Med ; 56(2): 148-154, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31976636

RESUMEN

BACKGROUND: Performance and perceived satisfaction of daily occupations in people with multiple sclerosis (MS) can affect the perception of their quality of life and be impacted by the level of fatigue. AIM: To describe the performance and occupational self-perception, as well as to analyze whether there is a relationship between the perception of occupational performance and the quality of life and perceived fatigue. DESIGN: A descriptive cross-sectional study. SETTING: Participants were referred by the services of Neurology of the various hospitals in Madrid. The assessment process was performed either at the MS' associations, in the participants' home, or at the Laboratory of Cognitive Intervention of the Health Sciences Faculty of the University. POPULATION: A total sample of 30 people with MS (pwMS) selected by non-probabilistic consecutive sampling during a three-months uptake patient recruitment period. METHODS: The outcome measures used were the Canadian Occupational Performance Measure (COPM), the Modified Fatigue Impact Scale (MFIS) and the Multiple Sclerosis Quality of Life 54 (MSQoL-54). Descriptive analysis, parametric and non-parametric tests and multiple linear regression models were used. RESULTS: A statistically significant positive correlation was found between occupational performance and physical and mental health. Also, high physical health scores were associated with high satisfaction scores. Multiple regression models indicated that high levels of satisfaction were associated with high levels of physical health (P= 0.013). CONCLUSIONS: The better the perception of the physical aspects that influence the quality of life, the better the perceived satisfaction of pwMS. Fatigue may not influence self-perceived satisfaction and performance. CLINICAL REHABILITATION IMPACT: The physical factors affecting perceived satisfaction should be considered when planning interventions to promote quality of life in pwMS. Although fatigue associated with MS may influence perceived performance and satisfaction, no relevant associations were found between variables.


Asunto(s)
Actividades Cotidianas/psicología , Fatiga/fisiopatología , Fatiga/psicología , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/psicología , Calidad de Vida/psicología , Adulto , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad
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