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1.
Rev Clin Esp (Barc) ; 224(2): 96-104, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38253256

RESUMEN

INTRODUCTION: Genetic studies have shown associations of several single nucleotide polymorphisms (SNP) with different rates of progression and variation in susceptibility to HIV infection. This study aimed to estimate the frequency of ccr5Δ32, IL-6-174G/C, IFN-γ+874T/A and IL-10-1082A/G polymorphisms in Cuban HIV-infected patients and a group of sero-discordant couples to assess their influence on risk and disease progression. METHODS: A cross-sectional study was carried out on 120 subjects registered at the Institute of Tropical Medicine «Pedro Kour¼ (IPK) and the Ameijeiras Hospital from June 2018 until December 2019. The amplification of fragments of the ccr5, IL-6, IFN-γ and IL-10 genes was performed by polymerase chain reaction followed by identification of polymorphisms using the restriction fragment length polymorphism analysis for IL-6 with the restriction enzymes Nla III. Amplification Refractory Mutation System was used for IFN-γ and IL-10 genes. RESULTS: The allelic and genotypic distributions of the genes ccr5, IL-6, IFN-γ and IL-10 did not differ significantly between the two groups. Cell counts and plasma viral load values did not differ significantly between genotypes of the ccr5, IL-6, IFN-γ and IL-10 genes. Only the IL-6 GC genotype was associated with higher viral load values. The combination of alleles of the four considered SNPs showed a highly significant increase in the risk of HIV infection for one of them, but with a very low frequency (<1%). CONCLUSION: This study contributes to evaluating the frequency of these polymorphisms and their influence on biomarkers of the progression of HIV infection in the Cuban HIV-population.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Humanos , Infecciones por VIH/genética , Síndrome de Inmunodeficiencia Adquirida/genética , Interleucina-6/genética , Interleucina-10/genética , Estudios Transversales , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Receptores CCR5/genética
2.
Neural Comput Appl ; 35(3): 2291-2323, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36373133

RESUMEN

Deep learning techniques, in particular generative models, have taken on great importance in medical image analysis. This paper surveys fundamental deep learning concepts related to medical image generation. It provides concise overviews of studies which use some of the latest state-of-the-art models from last years applied to medical images of different injured body areas or organs that have a disease associated with (e.g., brain tumor and COVID-19 lungs pneumonia). The motivation for this study is to offer a comprehensive overview of artificial neural networks (NNs) and deep generative models in medical imaging, so more groups and authors that are not familiar with deep learning take into consideration its use in medicine works. We review the use of generative models, such as generative adversarial networks and variational autoencoders, as techniques to achieve semantic segmentation, data augmentation, and better classification algorithms, among other purposes. In addition, a collection of widely used public medical datasets containing magnetic resonance (MR) images, computed tomography (CT) scans, and common pictures is presented. Finally, we feature a summary of the current state of generative models in medical image including key features, current challenges, and future research paths.

3.
J Endocrinol Invest ; 46(1): 141-149, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35943722

RESUMEN

PURPOSE: Simple screening tests to determine whether Cushing's syndrome (CS) should be ruled out are lacking. Tools that enable early diagnosis could reduce morbidity and associated sequelae. The potential of glucocorticoid-induced changes in the white blood cell (WBC) count for raising suspicion of CS is assessed. METHODS: This was a retrospective case‒control study. The WBC counts of 73 cases with CS and 146 matched controls were compared. The number of leukocytes (Leu), the number and percentage of neutrophils (N, Np), the number and percentage of lymphocytes (L, Lp), neutrophil-to-lymphocyte differences in the number and percentage (N-L, Np-Lp), neutrophil-to-lymphocyte ratio in the number and percentage (NLR, NLRp), and leukocyte-to-lymphocyte differences (Leu-L) were evaluated. The area under the ROC curve (AUC) was calculated for each of these parameters. Reference values were estimated that could help disclose occult CS. RESULTS: All ten parameters showed significant differences between cases and controls. The AUC was greater than 0.7 for all ten parameters, and was the best for the NLRp and Lp (AUC: 0.89). An Lp of 23.9% showed a diagnostic accuracy of 84.9% for the diagnosis of CS. The concordance of an Lp below 24% and more than 8000 leucocytes had a PPV of 78.2% for CS, while the pairing of an Lp over 24% and a Leu below 8000 cells had an NPV of 97.3% for CS. CONCLUSION: WBC count assessment can be an effective tool to raise suspicion of CS, prompting diagnostic testing. This simple and universally available test may allow earlier diagnosis of CS before highly evolved phenotypes develop.


Asunto(s)
Síndrome de Cushing , Humanos , Síndrome de Cushing/diagnóstico , Estudios Retrospectivos , Estudios de Casos y Controles , Recuento de Leucocitos , Linfocitos , Neutrófilos
4.
Rehabilitacion (Madr) ; 56(2): 99-107, 2022.
Artículo en Español | MEDLINE | ID: mdl-33814157

RESUMEN

INTRODUCTION AND OBJECTIVES: Cardiac rehabilitation has the highest level of recognition in medical guideline references, however there are still little-explored training modalities. We study the effects of an interdisciplinary program after acute coronary syndrome (ACS) in phase II secondary prevention. METHODS: Between January 2008 and December 2018, 439 patients with stable ischemic heart disease and preserved systolic function were included, as maximum 2 month after the ACS. A combined aerobic resistance training program in a variable continuous method and muscle toning with overload and/or ballast was applied, in addition to nutritional counseling and psychological-educational therapy for 12 weeks. RESULTS: 378 patients finished. The functional capacity increases in the incremental stress test (1.76 METS; CI 95%: 1.59-1.96, p < 0.001) and in the six minutes walking test (32.58 m; CI 95%: 29.24-35.92, p < 0.001). Leisure physical activity in IPAQ increased (763.27 min/week; CI 95%: 583.31-943.16, p < 0.001) and the time sitting during the week decreased (-28.85 min/day; CI 95%: -43.94 to -13.77, p < 0.001). Also, eating habits improved in PREDIMED (2.58 units; CI 95%: 1.43-3.73, p < 0.001), decreased body weight (-0.88 kg; CI 95%: -1.26 to -0.49, p < 0.001), the abdominal perimeter (1.57 cm; CI 95%: 2.23-0.90, p < 0.001) and adipose tissue (-0.80%; CI 95%: -1.10 to -0.51, p < 0.001). CONCLUSIONS: An interdisciplinary program with high intensity variable continuous training combined with dynamic muscle toning increases functional capacity, the level of physical activity, improves body composition and eating habits in ACS patients.


Asunto(s)
Síndrome Coronario Agudo , Entrenamiento de Fuerza , Síndrome Coronario Agudo/terapia , Ejercicio Físico/fisiología , Prueba de Esfuerzo , Humanos , Entrenamiento de Fuerza/métodos , Prueba de Paso
6.
PLoS One ; 15(11): e0241701, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33166342

RESUMEN

This work presents an alternative method to represent documents based on LDA (Latent Dirichlet Allocation) and how it affects to classification algorithms, in comparison to common text representation. LDA assumes that each document deals with a set of predefined topics, which are distributions over an entire vocabulary. Our main objective is to use the probability of a document belonging to each topic to implement a new text representation model. This proposed technique is deployed as an extension of the Weka software as a new filter. To demonstrate its performance, the created filter is tested with different classifiers such as a Support Vector Machine (SVM), k-Nearest Neighbors (k-NN), and Naive Bayes in different documental corpora (OHSUMED, Reuters-21578, 20Newsgroup, Yahoo! Answers, YELP Polarity, and TREC Genomics 2015). Then, it is compared with the Bag of Words (BoW) representation technique. Results suggest that the application of our proposed filter achieves similar accuracy as BoW but greatly improves classification processing times.


Asunto(s)
Almacenamiento y Recuperación de la Información/métodos , Máquina de Vectores de Soporte , Algoritmos , Teorema de Bayes , Análisis por Conglomerados , Humanos
7.
Clin Chim Acta ; 510: 573-580, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32791139

RESUMEN

BACKGROUND: Monoclonal protein (M-protein) concentrations are measured by serum protein electrophoresis (SPE). Two methods are used for demarcating the M-protein area in the electropherogram: perpendicular drop (PD) and tangent skimming (TS). The aim of this study was tocompare both methods and to establish which is the most accurate and precise. METHODS: We studied 24 sera containing M-protein (5-44 g/L). The systematic error (SE) was evaluated in a dilution series of 12 sera. Within-day, between-day, and interobserver variability were assessed. SPE was performed by capillary and agarose gel electrophoresis. M-protein concentrations were measured using both cutoff methods. RESULTS: The PD method shows a constant SE ranged 1.00-2.27 g/L, while constant SE for TS is ranged -0.30--0.57 g/L. None of the cutoff methods or electrophoretic methods showed a proportional SE, with the exception of the TS method in capillary electrophoresis for ß-migrating M-protein. The PD method was more precise than the TS method in all three estimates of imprecision. An increased CV for concentrations < 10 g/L in between-day imprecision was observed with the TS method. Interobserver imprecision was greater for M-protein concentrations < 17 g/L for both cutoff methods (14.85%, 26.42% respectively). CONCLUSIONS: Despite being less precise, the TS method provides a more accurate measurement of M-protein concentration.


Asunto(s)
Anticuerpos Monoclonales , Electroforesis Capilar , Electroforesis de las Proteínas Sanguíneas , Humanos , Pruebas Inmunológicas
8.
J Matern Fetal Neonatal Med ; 33(16): 2805-2811, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30563391

RESUMEN

Introduction. To evaluate the feasibility of an online learning process for performing and analyzing 3D/4D transperineal ultrasound imaging of the pelvic floor.Materials and methods: A prospective study was conducted with 20 patients. The learning process of three inexperienced examiners (IEs) performing and analyzing 3D/4D transperineal ultrasound volumes was evaluated. The learning process for the IEs was conducted online by an expert examiner (EE); no face-to-face tutoring was provided. The IEs' competency and analysis of the volumes were estimated using the intraclass correlation coefficient (ICC).Results: The interobserver analysis of the levator hiatus dimensions provided by the EE and those from each IE (for the 20 studied cases) had ICCs ranging from 0.81 to 0.96. The dimensions of the levator hiatus performed by the IEs for the first 10 patients showed ICCs ranging from 0.55 to 0.9. However, when the IEs proceeded with the next 10 patients, they obtained ICCs ranging from 0.81 to 0.96.Conclusions: Conducting 3D/4D transperineal ultrasound of the pelvic floor is a technique that can be learned online in a short period of time. A learning programme designed specifically for this purpose provides excellent reliability.Key Message: Conducting 3D/4D transperineal ultrasound of the pelvic floor is a technique that can be learned online in a short period of time.


Asunto(s)
Educación a Distancia/métodos , Imagenología Tridimensional/métodos , Diafragma Pélvico/diagnóstico por imagen , Ultrasonografía/métodos , Estudios de Factibilidad , Femenino , Humanos , Variaciones Dependientes del Observador , Embarazo , Estudios Prospectivos
9.
J Drug Target ; 27(5-6): 573-581, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30289743

RESUMEN

Neuregulin-1 loaded poly(lactic-co-glycolic acid) (PLGA) microparticles hold great promise for treating acute myocardial infarction, as they have been proved to recover heart function and induce positive heart remodelling in preclinical studies. More recently, the inflammatory response of the heart after acute myocardial infarction (AMI) has been identified as one of the major mechanisms in cardiac tissue remodelling and repair. However, the connection between neuregulin-1 PLGA microparticles and inflammation is still not well characterised. In the present study we assessed this relationship in a mouse AMI model. First, in vitro evidence indicated that neuregulin-1 PLGA microparticles induced a macrophage polarisation toward a regenerative phenotype (CD206+ cells), preventing macrophages from evolving toward the inflammatory phenotype (B7-2+ cells). This correlated with in vivo experiments, where neuregulin-1 PLGA microparticles locally improved the CD206+/B7-2+ ratio. Moreover, neuregulin-1 PLGA microparticles were administered at different time points (15 min, 24, 72 and 168 h) after infarction induction without causing secondary inflammatory issues. The time of treatment administration did not alter the inflammatory response. Taken together, these results suggest that neuregulin-1 PLGA microparticles can be administered depending on the therapeutic window of the encapsulated drug and that they enhance the heart's reparative inflammatory response after acute myocardial infarction, helping cardiac tissue repair.


Asunto(s)
Portadores de Fármacos/química , Corazón/fisiología , Macrófagos/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológico , Neurregulina-1/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Regeneración , Animales , Línea Celular , Modelos Animales de Enfermedad , Corazón/efectos de los fármacos , Corazón/fisiopatología , Macrófagos/fisiología , Ratones , Ratones Endogámicos C57BL , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Neurregulina-1/administración & dosificación , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico
10.
J Investig Allergol Clin Immunol ; 28(4): 246-252, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29465401

RESUMEN

BACKGROUND AND OBJECTIVE: Few studies have evaluated adherence to anaphylaxis guidelines in emergency departments (EDs). Objective: The objective of this study was to evaluate adherence to anaphylaxis guidelines in the ED of a tertiary hospital. METHODS: Medical records of patients attended in the ED of University Hospital of Salamanca, Spain were reviewed. Those patients fulfilling the anaphylaxis criteria proposed by the NIAID/FAAN were selected. RESULTS: During a 1-year period, we identified 89 patients (74 adults and 15 children). The anaphylactic reaction was moderate in 65% of adults, severe in 34%, and very severe in 1%. In children, all reactions were moderate. Fewer than half of the patients (42%) received adrenaline in the ED; this was administered intramuscularly in only 19% of cases. As for the severity of the reaction, 65% of patients with moderate reactions and 42% with severe reactions were not treated with adrenaline. At discharge from the ED, an adrenaline auto-injector was recommended to only 5.6% of patients. Fifty-two percent of patients received a documented allergy referral (57% adults vs 27% children, P=.047), 29% instructions about avoidance of triggers (31% adults vs 20% children, NS), and 51% written instructions for recognition of anaphylaxis warning signs (41% adults vs 100% children, P<.001). CONCLUSIONS: The results of the study show a large discrepancy between recommendations in guidelines and management of anaphylaxis in the ED. Additional training efforts are needed to improve the treatment of patients with anaphylactic reactions.


Asunto(s)
Anafilaxia/prevención & control , Epinefrina/administración & dosificación , Hipersensibilidad/epidemiología , Adolescente , Adulto , Anciano , Anafilaxia/etiología , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Humanos , Hipersensibilidad/complicaciones , Lactante , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , España/epidemiología , Centros de Atención Terciaria , Adulto Joven
11.
Neuroscience ; 361: 144-156, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-28823819

RESUMEN

The pathological hallmark of Parkinson's disease (PD) is the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc), and the resulting striatal dopamine deficiency, which are responsible for the classic motor features. Although a diagnosis of PD relies on the clinical effects of dopamine deficiency, this disease is also associated with other neurotransmitter deficits that are recognized as causing various motor and non-motor symptoms. However, the cause of dopaminergic nigral neurodegeneration in PD and the underlying mechanisms remain unknown. While animal models are considered valuable tools with which to investigate dopaminergic cell vulnerability, rodent models usually fail to mimic the neurodegeneration progression that occurs in human PD. To find a convenient rat model for studying the progression of dopaminergic cell degeneration and motor signs, we have developed a progressive rodent model using a repeated daily, intraventricular administration of the neurotoxin 6-hydroxydopamine (6-OHDA) (100µg/day) in awakened rats for 1 to 10 consecutive days. The short- (6-day) and long-term (32-day) progression of motor alterations was studied. This model leads to a bilateral and progressive increase in catalepsy (evident from the 3rd infusion in the short-term groups (p<0.01) and from the 7th infusion in the long-term groups (p<0.01), which was associated with a progressive nigrostriatal dopaminergic deficit. All together this makes the new model an interesting experimental tool to investigate the mechanisms involved in the progression of dopaminergic neurodegeneration.


Asunto(s)
Cuerpo Estriado/efectos de los fármacos , Modelos Animales de Enfermedad , Oxidopamina/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Sustancia Negra/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Neuronas Dopaminérgicas/efectos de los fármacos , Masculino , Oxidopamina/administración & dosificación , Enfermedad de Parkinson/fisiopatología , Ratas Sprague-Dawley , Tiempo
14.
Transplant Proc ; 48(9): 2913-2916, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27932106

RESUMEN

INTRODUCTION: The 2013 Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline suggests measuring cystatin C (sCys) in adults with glomerular filtration rate (GFR) based on creatinine (sCr) between 45 and 59 mL/min/1.73 m2 if confirmation of chronic kidney disease (CKD) is required. There is not enough evidence to recommend the use of sCys or sCr to estimate GFR in kidney transplant recipients. OBJECTIVES: Our aims were to describe the evolution of sCr, sCys, and GFR in a group of kidney transplant patients and to determine their association with some markers of morbidity at 1 year. METHODS: A total of 54 patients were included. Analytical and clinical data were recorded. Renal function was analyzed using the CKD Epidemiology Collaboration (EPI) sCr equation and CKD-EPI sCys equation. RESULTS: sCys-estimated GFR was higher than estimated from sCr by CKD-EPI. The values of sCys have more variability than those of sCr. The agreement between the stages of CKD by sCr or sCys-estimated GFR measured by Cohen's kappa coefficient was only fair. One-year CKD-associated variables correlated differently with sCr and sCys-estimated GFR. Hemoglobin, uric acid, calcium, and phosphorus related to sCr-estimated GFR, whereas serum albumin was associated with sCys-estimated GFR. CONCLUSIONS: sCys values have a higher variability than sCr in kidney transplant recipients. sCys- or sCr-based GFRs have a nonsimilar behavior in these patients with weak agreement to stratify CKD stages and a different relationship to CKD-related comorbid conditions.


Asunto(s)
Creatinina/metabolismo , Cistatina C/metabolismo , Trasplante de Riñón , Trasplantes/fisiología , Biomarcadores/metabolismo , Femenino , Tasa de Filtración Glomerular/fisiología , Humanos , Riñón/fisiología , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/cirugía
15.
Comput Methods Programs Biomed ; 136: 119-30, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27686709

RESUMEN

In text classification problems, the representation of a document has a strong impact on the performance of learning systems. The high dimensionality of the classical structured representations can lead to burdensome computations due to the great size of real-world data. Consequently, there is a need for reducing the quantity of handled information to improve the classification process. In this paper, we propose a method to reduce the dimensionality of a classical text representation based on a clustering technique to group documents, and a previously developed Hidden Markov Model to represent them. We have applied tests with the k-NN and SVM classifiers on the OHSUMED and TREC benchmark text corpora using the proposed dimensionality reduction technique. The experimental results obtained are very satisfactory compared to commonly used techniques like InfoGain and the statistical tests performed demonstrate the suitability of the proposed technique for the preprocessing step in a text classification task.


Asunto(s)
Análisis por Conglomerados , Modelos Teóricos , Cadenas de Markov
16.
Ultrasonics ; 71: 177-182, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27387418

RESUMEN

By using the principles behind phononic crystals, a periodic array of circular holes made along the polarization thickness direction of piezoceramic resonators are used to stop the planar resonances around the thickness mode band. In this way, a piezoceramic resonator adequate for operation in the thickness mode with an in phase vibration surface is obtained, independently of its lateral shape. Laser vibrometry, electric impedance tests and finite element models are used to corroborate the performances of different resonators made with this procedure. This method can be useful in power ultrasonic devices, physiotherapy and other external medical power ultrasound applications where piston-like vibration in a narrow band is required.

18.
Transbound Emerg Dis ; 63(5): 564-73, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25476549

RESUMEN

African horse sickness (AHS) is one of the most important vector-borne viral infectious diseases of equines, transmitted mainly by Culicoides spp. The re-emergence of Culicoides-borne diseases in Europe, such as the recent bluetongue (BT) or Schmallenberg outbreaks, has raised concern about the potential re-introduction and further spread of AHS virus (AHSV) in Europe. Spain has one of the largest European equine populations. In addition, its geographical, environmental and entomological conditions favour AHSV infections, as shown by the historical outbreaks in the 1990s. The establishment of risk-based surveillance strategies would allow the early detection and rapid control of any potential AHSV outbreak. This study aimed to identify the areas and time periods that are suitable or at high risk for AHS occurrence in Spain using a GIS-based multicriteria decision framework. Specifically risk maps for AHS occurrence were produced using a weighted linear combination of the main risk factors of disease, namely extrinsic incubation period, equine density and distribution of competent Culicoides populations. Model results revealed that the south-western and north-central areas of Spain and the Balearic Islands are the areas at the highest risk for AHSV infections, particularly in late summer months. Conversely, Galicia, Castile and Leon and La Rioja can be considered as low-risk regions. This result was validated with historical AHS and BT outbreaks in Spain, and with the Culicoides vector distribution area. The model results, together with current Spanish equine production features, should provide the foundations to design risk-based and more cost-effective surveillance strategies for the early detection and rapid control potential of AHS outbreaks in Spain.


Asunto(s)
Virus de la Enfermedad Equina Africana , Enfermedad Equina Africana/epidemiología , Enfermedad Equina Africana/prevención & control , Animales , Ceratopogonidae/virología , Brotes de Enfermedades/veterinaria , Caballos/virología , Insectos Vectores , Estaciones del Año , Ovinos , España/epidemiología
19.
Biomed Res Int ; 2015: 878291, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25879039

RESUMEN

Support vector machine (SVM) is a powerful technique for classification. However, SVM is not suitable for classification of large datasets or text corpora, because the training complexity of SVMs is highly dependent on the input size. Recent developments in the literature on the SVM and other kernel methods emphasize the need to consider multiple kernels or parameterizations of kernels because they provide greater flexibility. This paper shows a multikernel SVM to manage highly dimensional data, providing an automatic parameterization with low computational cost and improving results against SVMs parameterized under a brute-force search. The model consists in spreading the dataset into cohesive term slices (clusters) to construct a defined structure (multikernel). The new approach is tested on different text corpora. Experimental results show that the new classifier has good accuracy compared with the classic SVM, while the training is significantly faster than several other SVM classifiers.


Asunto(s)
Minería de Datos , Reconocimiento de Normas Patrones Automatizadas/métodos , Programas Informáticos , Máquina de Vectores de Soporte , Algoritmos , Inteligencia Artificial , Humanos
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