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1.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36679733

RESUMEN

In the last decade, biosignals have attracted the attention of many researchers when designing novel biometrics systems. Many of these works use cardiac signals and their representation as electrocardiograms (ECGs). Nowadays, these solutions are even more realistic since we can acquire reliable ECG records by using wearable devices. This paper moves in that direction and proposes a novel approach for an ECG identification system. For that, we transform the ECG recordings into Gramian Angular Field (GAF) images, a time series encoding technique well-known in other domains but not very common with biosignals. Specifically, the time series is transformed using polar coordinates, and then, the cosine sum of the angles is computed for each pair of points. We present a proof-of-concept identification system built on a tuned VGG19 convolutional neural network using this approach. We confirm our proposal's feasibility through experimentation using two well-known public datasets: MIT-BIH Normal Sinus Rhythm Database (subjects at a resting state) and ECG-GUDB (individuals under four specific activities). In both scenarios, the identification system reaches an accuracy of 91%, and the False Acceptance Rate (FAR) is eight times higher than the False Rejection Rate (FRR).


Asunto(s)
Arritmias Cardíacas , Identificación Biométrica , Humanos , Redes Neurales de la Computación , Electrocardiografía/métodos , Identificación Biométrica/métodos , Biometría , Algoritmos
2.
Allergol Immunopathol (Madr) ; 50(3): 101-105, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35527662

RESUMEN

BACKGROUND: Patients with primary antibody deficiencies, such as Common Variable Immunodeficiency (CVID), have some problems to assess immune response after coronavirus disease (COVID) vaccination. Cutaneous delayed-type hypersensitivity (DTH) has the potential to be used as a useful, simple, and cheaper tool to assess T-cell (T lymphocyte) function. METHODS: Seventeen patients with CVID, a rare disease, received two doses of the mRNA-based Pfizer-BioNTech COVID-19 vaccine. Humoral Immune Response (HIR) was determined by measuring specific immunoglobulin G (IgG) antibodies, and Cellular Immune Response (CIR) was evaluated using an ex vivo interferon-gamma release assay (IGRA) and in vivo by DTH skin test. RESULTS: Two weeks after the second dose of the vaccine, 12 out of 17 CVID patients have high optical density (OD) ratios of specific anti-spike protein (S) IgG whereas five patients were negative or low. Ex vivo CIR was considered positive in 14 out of 17 S1-stimulated patients. Unspecific stimulation was positive in all 17 patients showing no T-cell defect. A positive DTH skin test was observed in 16 CVID patients. The only patient with negative DTH also had negative ex vivo CIR. CONCLUSIONS: The use of DTH to evaluate CIR was validated with an optimal correlation with the ex vivo CIR. The CIR after vaccination in patients with antibody deficiencies seems to have high precision and more sensitivity to antibodies-based methods in CVID. CLINICAL IMPLICATIONS: There is a remarkable correlation between cutaneous DTH and ex vivo IGRA after COVID vaccination. A COVID-specific skin DTH test could be implemented in large populations. CAPSULE SUMMARY: Cutaneous delayed-type hypersensitivity has the potential to be used as a useful, simple, and cheaper tool to assess T-cell functioning.


Asunto(s)
COVID-19 , Inmunodeficiencia Variable Común , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina G , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunación
3.
Sensors (Basel) ; 19(9)2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31052275

RESUMEN

Today, medical equipment or general-purpose devices such as smart-watches or smart-textiles can acquire a person's vital signs. Regardless of the type of device and its purpose, they are all equipped with one or more sensors and often have wireless connectivity. Due to the transmission of sensitive data through the insecure radio channel and the need to ensure exclusive access to authorised entities, security mechanisms and cryptographic primitives must be incorporated onboard these devices. Random number generators are one such necessary cryptographic primitive. Motivated by this, we propose a True Random Number Generator (TRNG) that makes use of the GSR signal measured by a sensor on the body. After an exhaustive analysis of both the entropy source and the randomness of the output, we can conclude that the output generated by the proposed TRNG behaves as that produced by a random variable. Besides, and in comparison with the previous proposals, the performance offered is much higher than that of the earlier works.

4.
Sensors (Basel) ; 19(11)2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31159311

RESUMEN

Parkinson's Disease (PD) is currently the second most common neurodegenerative disease. One of the most characteristic symptoms of PD is resting tremor. Local Field Potentials (LFPs) have been widely studied to investigate deviations from the typical patterns of healthy brain activity. However, the inherent dynamics of the Sub-Thalamic Nucleus (STN) LFPs and their spatiotemporal dynamics have not been well characterized. In this work, we study the non-linear dynamical behaviour of STN-LFPs of Parkinsonian patients using ε -recurrence networks. RNs are a non-linear analysis tool that encodes the geometric information of the underlying system, which can be characterised (for example, using graph theoretical measures) to extract information on the geometric properties of the attractor. Results show that the activity of the STN becomes more non-linear during the tremor episodes and that ε -recurrence network analysis is a suitable method to distinguish the transitions between movement conditions, anticipating the onset of the tremor, with the potential for application in a demand-driven deep brain stimulation system.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Máquina de Vectores de Soporte , Temblor/metabolismo , Femenino , Humanos , Masculino , Modelos Teóricos , Dinámicas no Lineales , Enfermedad de Parkinson/metabolismo
5.
Sensors (Basel) ; 18(9)2018 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-30134589

RESUMEN

Wireless Sensor Networks (WSNs) are a promising technology with applications in many areas such as environment monitoring, agriculture, the military field or health-care, to name but a few. Unfortunately, the wireless connectivity of the sensors opens doors to many security threats, and therefore, cryptographic solutions must be included on-board these devices and preferably in their design phase. In this vein, Random Number Generators (RNGs) play a critical role in security solutions such as authentication protocols or key-generation algorithms. In this article is proposed an avant-garde proposal based on the cardiac signal generator we carry with us (our heart), which can be recorded with medical or even low-cost sensors with wireless connectivity. In particular, for the extraction of random bits, a multi-level decomposition has been performed by wavelet analysis. The proposal has been tested with one of the largest and most publicly available datasets of electrocardiogram signals (202 subjects and 24 h of recording time). Regarding the assessment, the proposed True Random Number Generator (TRNG) has been tested with the most demanding batteries of statistical tests (ENT, DIEHARDERand NIST), and this has been completed with a bias, distinctiveness and performance analysis. From the analysis conducted, it can be concluded that the output stream of our proposed TRNG behaves as a random variable and is suitable for securing WSNs.


Asunto(s)
Electrocardiografía , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Tecnología Inalámbrica , Algoritmos , Conjuntos de Datos como Asunto , Femenino , Humanos , Masculino , Distribución Aleatoria , Análisis de Ondículas
6.
Anal Bioanal Chem ; 408(24): 6659-70, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27497969

RESUMEN

Selenium nanoparticles (SeNPs) were incorporated in a flexible multilayer plastic material using a water-base adhesive as vehicle for SeNPs. The antioxidant performance of the original solutions containing spherical SeNPs of 50-60 nm diameter, the adhesive containing these SeNPs, and the final multilayer plastic material to be used as food packaging were quantitatively measured. The radical scavenging capacity due to SeNPs was quantified by a free radical assay developed in the laboratory and by the diphenyl-1-picrylhydrazyl (DPPH) method. DPPH was not efficient to measure the scavenging capacity in the multilayer when the free radical scavenger is not in the surface in contact with it. Several multilayer laminated structures composed by [PET (20 m)-adhesive-LDPE (with variable thickness from 35 to 90 µm)] were prepared and measured, demonstrating for the first time that free radicals derived from oxygen (OH·, O2·, and O2H) cross the PE layer and arrive at the adhesive. SeNPs remain as such after manufacture and the final laminate is stable after 3 months of storage. The antioxidant multilayer is a non-migrating efficient free radical scavenger, able to protect the packaged product versus oxidation and extending the shelf life without being in direct contact with the product. Migration tests of both Se and SeNPs to simulants and hazelnuts demonstrated the non-migrating performance of this new active packaging. Graphical abstract ᅟ.


Asunto(s)
Embalaje de Alimentos/métodos , Depuradores de Radicales Libres/química , Nanopartículas/química , Selenio/química , Adhesivos/química , Compuestos de Bifenilo/química , Calidad de los Alimentos , Radicales Libres/química , Oxidación-Reducción , Picratos/química
7.
J Biomed Inform ; 55: 272-89, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25917056

RESUMEN

Bioengineering is a field in expansion. New technologies are appearing to provide a more efficient treatment of diseases or human deficiencies. Implantable Medical Devices (IMDs) constitute one example, these being devices with more computing, decision making and communication capabilities. Several research works in the computer security field have identified serious security and privacy risks in IMDs that could compromise the implant and even the health of the patient who carries it. This article surveys the main security goals for the next generation of IMDs and analyzes the most relevant protection mechanisms proposed so far. On the one hand, the security proposals must have into consideration the inherent constraints of these small and implanted devices: energy, storage and computing power. On the other hand, proposed solutions must achieve an adequate balance between the safety of the patient and the security level offered, with the battery lifetime being another critical parameter in the design phase.


Asunto(s)
Seguridad Computacional/instrumentación , Confidencialidad , Equipos y Suministros , Seguridad del Paciente , Prótesis e Implantes , Administración de la Seguridad/organización & administración , Diseño de Equipo , Análisis de Falla de Equipo , Seguridad de Equipos/métodos
8.
J Sep Sci ; 38(14): 2394-402, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25943946

RESUMEN

The behavior of 15 benzimidazoles, including their main metabolites, using several C18 columns with standard or narrow-bore diameters and different particle size and type were evaluated. These commercial columns were selected because their differences could affect separation of benzimidazoles, and so they can be used as alternative columns. A simple screening method for the analysis of benzimidazole residues and their main metabolites was developed. First, the separation of benzimidazoles was optimized using a Kinetex C18 column; later, analytical performances of other columns using the above optimized conditions were compared and then individually re-optimized. Critical pairs resolution, analysis run time, column type and characteristics, and selectivity were considered for chromatographic columns comparison. Kinetex XB was selected because it provides the shortest analysis time and the best resolution of critical pairs. Using this column, the separation conditions were re-optimized using a factorial design. Separations obtained with the different columns tested can be applied to the analysis of specific benzimidazoles residues or other applications.


Asunto(s)
Bencimidazoles/análisis , Cromatografía/instrumentación , Bencimidazoles/química , Técnicas de Química Analítica , Cromatografía/métodos , Concentración de Iones de Hidrógeno , Cinética , Ligandos , Tamaño de la Partícula , Porosidad , Análisis de Componente Principal , Reproducibilidad de los Resultados , Solventes
9.
J Med Syst ; 39(11): 148, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26364201

RESUMEN

As a result of the increased demand for improved life styles and the increment of senior citizens over the age of 65, new home care services are demanded. Simultaneously, the medical sector is increasingly becoming the new target of cybercriminals due the potential value of users' medical information. The use of biometrics seems an effective tool as a deterrent for many of such attacks. In this paper, we propose the use of electrocardiograms (ECGs) for the identification of individuals. For instance, for a telecare service, a user could be authenticated using the information extracted from her ECG signal. The majority of ECG-based biometrics systems extract information (fiducial features) from the characteristics points of an ECG wave. In this article, we propose the use of non-fiducial features via the Hadamard Transform (HT). We show how the use of highly compressed signals (only 24 coefficients of HT) is enough to unequivocally identify individuals with a high performance (classification accuracy of 0.97 and with identification system errors in the order of 10(-2)).


Asunto(s)
Identificación Biométrica/instrumentación , Electrocardiografía/instrumentación , Servicios de Atención de Salud a Domicilio , Procesamiento de Señales Asistido por Computador/instrumentación , Telemedicina/instrumentación , Algoritmos , Seguridad Computacional , Humanos
10.
J Med Syst ; 39(11): 155, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26385550

RESUMEN

Parkinsons disease is a complex neurodegenerative disorder for which patients present many symptoms, tremor being the main one. In advanced stages of the disease, Deep Brain Stimulation is a generalized therapy which can significantly improve the motor symptoms. However despite its beneficial effects on treating the symptomatology, the technique can be improved. One of its main limitations is that the parameters are fixed, and the stimulation is provided uninterruptedly, not taking into account any fluctuation in the patients state. A closed-loop system which provides stimulation by demand would adjust the stimulation to the variations in the state of the patient, stimulating only when it is necessary. It would not only perform a more intelligent stimulation, capable of adapting to the changes in real time, but also extending the devices battery life, thereby avoiding surgical interventions. In this work we design a tool that learns to recognize the principal symptom of Parkinsons disease and particularly the tremor. The goal of the designed system is to detect the moments the patient is suffering from a tremor episode and consequently to decide whether stimulation is needed or not. For that, local field potentials were recorded in the subthalamic nucleus of ten Parkinsonian patients, who were diagnosed with tremor-dominant Parkinsons disease and who underwent surgery for the implantation of a neurostimulator. Electromyographic activity in the forearm was simultaneously recorded, and the relation between both signals was evaluated using two different synchronization measures. The results of evaluating the synchronization indexes on each moment represent the inputs to the designed system. Finally, a fuzzy inference system was applied with the goal of identifying tremor episodes. Results are favourable, reaching accuracies of higher 98.7% in 70% of the patients.


Asunto(s)
Estimulación Encefálica Profunda/instrumentación , Lógica Difusa , Enfermedad de Parkinson/terapia , Temblor/terapia , Electromiografía , Femenino , Humanos , Masculino , Procesamiento de Señales Asistido por Computador , Núcleo Subtalámico
11.
Anal Bioanal Chem ; 406(30): 7949-58, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25311192

RESUMEN

The use of enriched Se isotopes as tracers has provided important information on Se metabolism. However, selenium isotopes are expensive and difficult to obtain. A simple and cheap strategy based on the production of [(77)Se]-methylselenocysteine ([(77)Se]-MeSeCys) when preparing sauerkraut in the presence of [(77)Se]-selenite was developed. The resulting [(77)Se]-MeSeCys was used for evaluating the metabolic transformation of MeSeCys in Wistar rats, by feeding them with an AIN-93 M diet containing 20 % sauerkraut enriched in [(77)Se]-MeSeCys. Organs (liver, kidney, brain, testicles, and heart) were obtained after seven days of treatment and subjected to total selenium and selenium-speciation analysis by high-performance liquid chromatography coupled with isotope-dilution-analysis inductively-coupled-plasma mass spectrometry (HPLC-IDA-ICP-MS). Analysis of (77)Se-labeled organs revealed a prominent increase (more than 100 % Se-level enhancement) of selenium in the kidney and heart, whereas in the liver selenium concentration only increased by up to 20 % and it remained constant in the brain and testicles. (77)Se-enriched-sauerkraut supplementation does not alter the concentration of other essential elements in comparison to controls except for in the heart and kidney, in which selenium was positively correlated with Mg, Zn, Cu, and Mo. HPLC-ICP-MS analysis of hydrolyzed extracts after carbamidomethylation of the (77)Se-labeled organs revealed the presence of [(77)Se]-SeCys and an unknown Se-containing peak, the identity of which could not be verified by electrospray-ionization (ESI)-MS-MS. Low amounts of [(77)Se]-MeSeCys were found in (77)Se-labeled liver and kidney extracts, suggesting the incorporation of this selenium species in its intact form.


Asunto(s)
Ácido Selenioso/química , Selenio/análisis , Selenio/metabolismo , Selenocisteína/análogos & derivados , Alimentación Animal , Animales , Cromatografía Líquida de Alta Presión , Riñón/metabolismo , Hígado/metabolismo , Masculino , Espectrometría de Masas , Miocardio/metabolismo , Ratas , Ratas Wistar , Selenocisteína/análisis , Selenocisteína/síntesis química , Selenocisteína/metabolismo
12.
Pediatr Pulmonol ; 58(2): 585-591, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36267002

RESUMEN

Autosomal dominant hyper IgE syndrome (AD-HIES) is a primary immunodeficiency caused by loss-of-function (LOF) mutations in the Signal Transducer and Activator of Transcription 3 (STAT3) gene. In these patients, performing a correct differential diagnosis of pulmonary infections is difficult and challenging, as they usually have atypical presentations. However, establishing a correct diagnostic and therapeutic approach is essential, as pulmonary complications are responsible for high morbidity and mortality rates in these patients. We report the case of a teenage girl with AD-HIES and respiratory symptoms and fever in whom performing a correct differential diagnosis was challenging.


Asunto(s)
Síndrome de Job , Factor de Transcripción STAT3 , Adolescente , Femenino , Humanos , Factor de Transcripción STAT3/genética , Diagnóstico Diferencial , Síndrome de Job/complicaciones , Síndrome de Job/diagnóstico , Síndrome de Job/genética , Mutación
13.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37111331

RESUMEN

Continuous evaluation of the coronavirus disease 2019 (COVID-19) vaccine effectiveness in hemodialysis (HD) patients is critical in this immunocompromised patient group with higher mortality rates due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The response towards vaccination in HD patients has been studied weeks after their first and second SARS-CoV-2 vaccination dose administration, but no further studies have been developed in a long-term manner, especially including both the humoral and cellular immune response. Longitudinal studies that monitor the immune response to COVID-19 vaccination in individuals undergoing HD are therefore necessary to prioritize vaccination strategies and minimize the pathogenic effects of SARS-CoV-2 in this high-risk group of patients. We followed up HD patients and healthy volunteers (HV) and monitored their humoral and cellular immune response three months after the second (V2+3M) and after the third vaccination dose (V3+3M), taking into consideration previous COVID-19 infections. Our cellular immunity results show that, while HD patients and HV individuals secrete comparable levels of IFN-γ and IL-2 in ex vivo stimulated whole blood at V2+3M in both naïve and COVID-19-recovered individuals, HD patients secrete higher levels of IFN-γ and IL-2 than HV at V3+3M. This is mainly due to a decay in the cellular immune response in HV individuals after the third dose. In contrast, our humoral immunity results show similar IgG binding antibody units (BAU) between HD patients and HV individuals at V3+3M, independently of their previous infection status. Overall, our results indicate that HD patients maintain strong cellular and humoral immune responses after repeated 1273-mRNA SARS-CoV-2 vaccinations over time. The data also highlights significant differences between cellular and humoral immunity after SARS-CoV-2 vaccination, which emphasizes the importance of monitoring both arms of the immune response in the immunocompromised population.

14.
Front Immunol ; 14: 1136308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37215146

RESUMEN

Introduction: Inborn errors of immunity (IEI) are a heterogeneous group of diseases caused by intrinsic defects of the immune system. Estimating the immune competence of immunocompromised patients for an infection risk assessment or after SARS-CoV-2 vaccination constituted a challenge. Methods: The aim of this study was to determine the humoral responses of patients with IEI through a comprehensive analysis of specific receptor-binding domain-positive (RBD+) IgG+ memory B cells (MBCs) by flow cytometry, together with routine S-specific IgG antibodies and QuantiFERON SARS-CoV-2 (T-cell response), before the vaccine and 3 weeks after a second dose. Results and discussion: We first analyzed the percentage of specific RBD+ IgG+ MBCs in healthy healthcare workers. Within the control group, there was an increase in the percentage of specific IgG+ RBD+ MBCs 21 days after the second dose, which was consistent with S-specific IgG antibodies.Thirty-one patients with IEI were included for the pre- and post-vaccination study; IgG+ RBD+ MBCs were not evaluated in 6 patients due to an absence of B cells in peripheral blood. We detected various patterns among the patients with IEI with circulating B cells (25, 81%): an adequate humoral response was observed in 12/25, consider by the detection of positive S-specific IgG antibodies and the presence of specific IgG+ RBD+ MBCs, presenting a positive T-cell response; in 4/25, very low S-specific IgG antibody counts correlated with undetectable events in the IgG+ RBD+ MBC compartment but with positive cellular response. Despite the presence of S-specific IgG antibodies, we were unable to detect a relevant percentage of IgG+ RBD+ MBCs in 5/25; however, all presented positive T-cell response. Lastly, we observed a profound failure of B and T-cell response in 3 (10%) patients with IEI, with no assessment of S-specific IgG antibodies, IgG+ RBD+ MBCs, and negative cellular response. The identification of specific IgG+ RBD+ MBCs by flow cytometry provides information on different humoral immune response outcomes in patients with IEI and aids the assessment of immune competence status after SARS-CoV-2 mRNA vaccine (BNT162b2), together with S-specific IgG antibodies and T-cell responses.


Asunto(s)
COVID-19 , Células B de Memoria , Humanos , Vacunas contra la COVID-19 , Vacuna BNT162 , Citometría de Flujo , COVID-19/prevención & control , SARS-CoV-2 , Vacunación , Personal de Salud , Inmunoglobulina G
15.
Front Immunol ; 14: 1197361, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37342345

RESUMEN

Purpose: The clinical spectrum of common variable immunodeficiency (CVID) includes predisposition to infections, autoimmune/inflammatory complications and malignancy. Liver disease is developed by a proportion of patients with CVID, but limited evidence is available about its prevalence, pathogenesis and prognostic outcome. This lack of evidence leads to the absence of guidelines in clinical practice. In this study, we aimed at defining the characteristics, course and management of this CVID complication in Spain. Methods: Spanish reference centers were invited to complete a cross-sectional survey. Thirty-eight patients with CVID-related liver disease from different hospitals were evaluated by a retrospective clinical course review. Results: In this cohort, abnormal liver function and thrombocytopenia were found in most of the patients (95% and 79% respectively), in keeping with the higher incidence of abnormal liver imaging and splenomegaly. The most common histological findings included nodular regenerative hyperplasia (NRH) and lymphocytic infiltration, which have been associated with portal hypertension (PHTN) leading to a poorer prognosis. Autoimmune/inflammatory complications occurred in 82% of the CVID patients that developed liver disease and 52% of the patients treated with immunomodulators showed a reduction in the liver function tests' abnormalities during treatment. Among the experts that conducted the survey, there was 80% or more consensus that the workup of CVID-related liver disease requires liver profile, abdominal ultrasound and transient elastography. The majority agreed that liver biopsy should be essential for diagnosis. There was 94% consensus that endoscopic studies should be performed in the presence of PHTN. However, there was 89% consensus that there is insufficient evidence on the management of these patients. Conclusion: Liver disease varies in severity and may contribute substantially to morbidity and mortality in patients with CVID. Hence the importance of close follow-up and screening of this CVID complication to prompt early targeted intervention. Further research is needed to evaluate the pathophysiology of liver disease in patients with CVID to identify personalized treatment options. This study emphasizes the urgent need to develop international guidelines for the diagnosis and management of this CVID complication.


Asunto(s)
Inmunodeficiencia Variable Común , Hipertensión Portal , Humanos , Estudios Retrospectivos , Inmunodeficiencia Variable Común/complicaciones , Inmunodeficiencia Variable Común/diagnóstico , Inmunodeficiencia Variable Común/terapia , Estudios Transversales , Hipertensión Portal/diagnóstico , Hipertensión Portal/etiología , Hipertensión Portal/terapia
16.
Cancer ; 118(1): 241-7, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21717449

RESUMEN

BACKGROUND: Several aromatase inhibitor studies have reported variations in the inhibitory potency of these agents that could lead to differences in clinical outcomes. In the current study, the authors formally evaluated the activity of anastrozole and exemestane in postmenopausal women with hormone-responsive, advanced breast cancer. METHODS: Postmenopausal women who had measurable disease according to Response Evaluation Criteria in Solid Tumors and had not received previous endocrine therapy for advanced breast cancer were randomized to receive either oral exemestane 25 mg daily or oral anastrozole 1 mg daily until they had disease progression. The primary endpoint was the objective response rate (ORR), and secondary endpoints included the clinical benefit rate (CBR), time to progression (TTP), overall survival, and safety. Crossover to the other aromatase inhibitor was permitted at the time of disease progression; ORR, CBR, and TTP after second-line treatment also were explored. RESULTS: In total, 103 patients were enrolled. The median patient age was 71.6 years, 52.4% of patients had visceral disease, and 75.8% of patients had ≥ 2 disease sites. Half of the patients had received previous tamoxifen, and 60% had received previous chemotherapy. The efficacy observed in the exemestane and anastrozole groups was an ORR of 36.2% and 46%, respectively; a CBR of 59.6% and 68%, respectively, and a TTP of 6.1 months and 12.1 months, respectively. At progression, 28 patients crossed over to the other aromatase inhibitor, including 16 patients who switched to exemestane (CBR, 43.7%; TTP, 4.4 months) and 12 patients who switched to anastrozole (CBR, 8.3%; TTP, 2 months). Both drugs were generally well tolerated, and no study drug-related serious adverse events were reported. CONCLUSIONS: In this phase 2 randomized trial, no significant differences in clinical activity were observed in favor of exemestane to justify a superiority phase 3 trial design in the first-line setting.


Asunto(s)
Androstadienos/uso terapéutico , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Nitrilos/uso terapéutico , Triazoles/uso terapéutico , Anciano , Anciano de 80 o más Años , Anastrozol , Androstadienos/efectos adversos , Neoplasias de la Mama/mortalidad , Estudios Cruzados , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Nitrilos/efectos adversos , Posmenopausia , Resultado del Tratamiento , Triazoles/efectos adversos
17.
Analyst ; 137(22): 5302-11, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23014190

RESUMEN

Mercury toxicity and its implications in development are a major concern, due to the major threat to ecosystems and human health that this compound represents. Although some of the effects of methylmercury (MeHg) exposure have been extensively studied, the molecular mechanisms of interaction between this compound and developing organisms are still not completely understood. To provide further insights into these mechanisms, we carried out a quantitative proteomic study (iTRAQ) using zebrafish larvae exposed to 5 µg L(-1) and 25 µg L(-1) MeHg as a model. In this study, a multidimensional approach combining isoelectric focusing (IEF) and strong cation exchange (SCX) followed by reversed phase liquid chromatography prior to MALDI TOF/TOF analysis was employed, which resulted in a substantial increase in proteome coverage. Among the proteins identified, 71 were found de-regulated by more than 1.5-fold, and implicated in embryonic development, protein synthesis, calcium homeostasis and energy production. Furthermore, morphological and histological analysis of exposed larvae was carried out, reflecting changes such as smaller swim bladder, remaining yolk, bent body axis and accumulation of blood in the heart, among others.


Asunto(s)
Cromatografía Líquida de Alta Presión , Desarrollo Embrionario/efectos de los fármacos , Compuestos de Metilmercurio/toxicidad , Proteoma/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Animales , Calcio/metabolismo , Cromatografía por Intercambio Iónico , Cromatografía de Fase Inversa , Metabolismo Energético , Focalización Isoeléctrica , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Compuestos de Metilmercurio/química , Péptidos/análisis , Pez Cebra/crecimiento & desarrollo
18.
Anal Bioanal Chem ; 404(2): 315-24, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22535442

RESUMEN

Understanding the molecular mechanisms underlying MeHg toxicity and the way in which this molecule interacts with living organisms is a critical point since MeHg represents a well-known risk to ecosystems and human health. We used a quantitative proteomic approach based on stable isotopic labeling by amino acids in cell culture in combination with SDS-PAGE and nanoflow LC-ESI-LTQ for analyzing the differential protein expression of hepatic cells associated to MeHg exposure. Seventy-eight proteins were found de-regulated by more than 1.5-fold. We identified a number of proteins involved in different essential biological processes including apoptosis, mitochondrial dysfunction, cellular trafficking and energy production. Among these proteins, we found several molecules whose de-regulation has been already related to MeHg exposure, thus confirming the usefulness of our discovery approach, and new ones that helped to gain a deeper insight into the biomolecular mechanisms related to MeHg-induced toxicity. Overexpression of several HSPs and the proteasome 26S subunit itself showed the proteasome system as a molecular target of toxic MeHg. As for the interaction networks, the top ranked was the nucleic acid metabolism, where many of the identified de-regulated proteins are involved.


Asunto(s)
Hígado/efectos de los fármacos , Compuestos de Metilmercurio/toxicidad , Proteínas/metabolismo , Apoptosis , Línea Celular Tumoral , Transporte de Electrón , Electroforesis en Gel de Poliacrilamida , Humanos , Hígado/citología , Hígado/metabolismo , Espectrometría de Masa por Ionización de Electrospray
20.
Chest ; 162(4): e161-e164, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36210107

RESUMEN

CASE PRESENTATION: A 15-year-old boy presented with three acute episodes of self-limited hemoptysis. He was being followed by the pediatric pulmonology department for necrotizing pneumonia and a right upper lobe lung abscess with residual pneumatocele 5 years earlier. He had also experienced recurrent perianal abscesses and more than 15 acute suppurative otitis media throughout his life, even after myringotomy and transtympanic drainage; methicillin-sensitive Staphyloccocus aureus was found in a culture of otic exudate. He had no known allergies and was not taking any drugs. The patient's father had presented with more than 20 skin abscesses and was carrier of methicillin-resistant S aureus. After necrotizing pneumonia and along with his family history, the patient had undergone a neutrophil oxidative burst test excluding chronic granulomatous disease; immunoglobulin levels and lymphocyte populations were within normal range.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía Necrotizante , Absceso , Adolescente , Niño , Hemoptisis/diagnóstico , Hemoptisis/etiología , Humanos , Inmunoglobulinas , Masculino , Meticilina
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