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BACKGROUND: Amivantamab plus carboplatin-pemetrexed (chemotherapy) with and without lazertinib demonstrated antitumor activity in patients with refractory epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) in phase I studies. These combinations were evaluated in a global phase III trial. PATIENTS AND METHODS: A total of 657 patients with EGFR-mutated (exon 19 deletions or L858R) locally advanced or metastatic NSCLC after disease progression on osimertinib were randomized 2 : 2 : 1 to receive amivantamab-lazertinib-chemotherapy, chemotherapy, or amivantamab-chemotherapy. The dual primary endpoints were progression-free survival (PFS) of amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy. During the study, hematologic toxicities observed in the amivantamab-lazertinib-chemotherapy arm necessitated a regimen change to start lazertinib after carboplatin completion. RESULTS: All baseline characteristics were well balanced across the three arms, including by history of brain metastases and prior brain radiation. PFS was significantly longer for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy [hazard ratio (HR) for disease progression or death 0.48 and 0.44, respectively; P < 0.001 for both; median of 6.3 and 8.3 versus 4.2 months, respectively]. Consistent PFS results were seen by investigator assessment (HR for disease progression or death 0.41 and 0.38 for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy, respectively; P < 0.001 for both; median of 8.2 and 8.3 versus 4.2 months, respectively). Objective response rate was significantly higher for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (64% and 63% versus 36%, respectively; P < 0.001 for both). Median intracranial PFS was 12.5 and 12.8 versus 8.3 months for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (HR for intracranial disease progression or death 0.55 and 0.58, respectively). Predominant adverse events (AEs) in the amivantamab-containing regimens were hematologic, EGFR-, and MET-related toxicities. Amivantamab-chemotherapy had lower rates of hematologic AEs than amivantamab-lazertinib-chemotherapy. CONCLUSIONS: Amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy improved PFS and intracranial PFS versus chemotherapy in a population with limited options after disease progression on osimertinib. Longer follow-up is needed for the modified amivantamab-lazertinib-chemotherapy regimen.
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Acrilamidas , Compuestos de Anilina , Anticuerpos Biespecíficos , Carcinoma de Pulmón de Células no Pequeñas , Indoles , Neoplasias Pulmonares , Morfolinas , Pirazoles , Pirimidinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carboplatino/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Progresión de la Enfermedad , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Inhibidores de Proteínas Quinasas/uso terapéuticoRESUMEN
Adequate stem cell harvesting is required for autologous hematopoietic transplantation. In deficient mobilizer patients, the collection of stem cells can be challenging because of the impossibility of achieving satisfactory CD34 cell counts with GCSF + - chemotherapy. Plerixafor is a potent and expensive drug that promotes the release of stem cells from the medullary niche to the peripheral blood and allows satisfactory harvests. We performed a retrospective analysis of 370 patients with myeloma and lymphoma harvested at our institution. 99 % of patients achieved satisfactory apheresis using Plerixafor in 45 %. Satisfactory harvests were obtained in patients mobilized with GCSF or plerixafor. In patients who used plerixafor, it was necessary to perform fewer apheresis procedures (P = 0.05). In multivariate analysis, the only factor that predicted the need for plerixafor was the presence of less than 30,000 CD34 / ul on the day of apheresis (OR 0.3. p < 0.001). Since we adopted the plerixafor protocol guided by CD34 counts, the number of patients with harvest failure has decreased. In conclusion, the rational and standardized use of plerixafor favors satisfactory harvest in patients who require autologous transplantation in South-American patients.
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BACKGROUND: Chlamydia abortus, an obligate intracellular pathogen with an affinity for placenta, causes reproductive failure. In non-pregnant animals, an initial latent infection is established until the next gestation, when the microorganism is reactivated, causing abortion. The precise mechanisms that trigger the awakening of C. abortus are still unknown. Sexual hormones such as estradiol and progesterone have been shown to affect the outcome of infection in other species of the family Chlamydiaceae, while estrogens increase chlamydial infection, progesterone has the opposite effect. To try to establish whether there is a relationship between these events and the latency/ reactivation of C. abortus in the reproductive tract of small ruminants, ovine endometrial (LE) and trophoblastic (AH-1) cells were treated with estradiol or progesterone prior to their infection with C. abortus. The results are compared with those obtained for treatment with penicillin prior to infection, which is a well-established model for studying persistent infection in other chlamydial species. Cells were examined by transmission electron microscopy, and an mRNA expression analysis of 16 genes related to the chlamydial developmental cycle was made. RESULTS: The changes observed in this study by the action of sex hormones seem to depend on the type of cell where the infection develops. In addition, while the changes are morphologically similar to those induced by treatment with penicillin, the patterns of gene expression are different. Gene expression patterns therefore, seem to depend on the persistence induced models of C. abortus used. Hormone treatments induced aberrant forms in infected endometrial cells but did not affect the chlamydial morphology in trophoblast cells. At the genetic level, hormones did not induce significant changes in the expression of the studied genes. CONCLUSIONS: The results suggest that penicillin induces a state of persistence in in vitro cultured C. abortus with characteristic morphological features and gene transcriptional patterns. However, the influence of hormones on the C. abortus developmental cycle is mediated by changes in the host cell environment. Furthermore, a persistent state in C. abortus cannot be characterised by a single profile of gene expression pattern, but may change depending on the model used to induce persistence.
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Chlamydia/efectos de los fármacos , Estradiol/farmacología , Progesterona/farmacología , Animales , Línea Celular , Chlamydia/crecimiento & desarrollo , Chlamydia/ultraestructura , Infecciones por Chlamydia/veterinaria , Femenino , Expresión Génica , Microscopía Electrónica de Transmisión/veterinaria , Penicilinas/administración & dosificación , ARN Mensajero , OvinosRESUMEN
Zhang (2019, https://doi.org/10.1002/wrcr.v54.4) criticizes several of the assumptions and parameter choices of the model of Kuil et al. (2018, https://doi.org/10.1002/2017WR021420) and claims that, due to an inconsistency in the irrigation equation, the key findings should be interpreted with much caution. We address each of the comments and show that the conclusions of Kuil et al. (2018, https://doi.org/10.1002/2017WR021420) remain fully valid.
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BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.
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Asma/diagnóstico , Asma/prevención & control , Niño , Preescolar , Femenino , Humanos , Masculino , MéxicoRESUMEN
BACKGROUND: Although highly prevalent throughout the world, the accurate prevalence of hemoglobinopathies in Spain is unknown. PROCEDURE: This study presents data on the national registry of hemoglobinopathies of patients with thalassemia major (TM), thalassemia intermedia (TI), and sickle cell disease (SCD) in Spain created in 2014. Fifty centers reported cases retrospectively. Data were registered from neonatal screening or from the first contact at diagnosis until last follow-up or death. RESULTS: Data of the 715 eligible patients were collected: 615 SCD (497 SS, 64 SC, 54 SBeta phenotypes), 73 thalassemia, 9 CC phenotype, and 18 other variants. Most of the SCD patients were born in Spain (65%), and 51% of these were diagnosed at newborn screening. Median age at the first diagnosis was 0.4 years for thalassemia and 1.0 years for SCD. The estimated incidence was 0.002 thalassemia cases and 0.03 SCD cases/1,000 live births. Median age was 8.9 years (0.2-33.7) for thalassemia and 8.1 years (0.2-32.8) for SCD patients. Stroke was registered in 16 SCD cases. Transplantation was performed in 43 TM and 23 SCD patients at a median age of 5.2 and 7.8 years, respectively. Twenty-one patients died (3 TM, 17 SCD, 1 CC) and 200 were lost to follow-up. Causes of death were related to transplantation in three patients with TM and three patients with SCD. Death did not seem to be associated with SCD in six patients, but nine patients died secondary to disease complications. Overall survival was 95% at 15 years of age. CONCLUSIONS: The registry provides data about the prevalence of hemoglobinopathies in Spain and will permit future cohort studies and the possibility of comparison with other registries.
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Hemoglobinopatías/epidemiología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Prevalencia , Sistema de Registros , España/epidemiologíaRESUMEN
Research gaps in understanding flood changes at the catchment scale caused by changes in forest management, agricultural practices, artificial drainage, and terracing are identified. Potential strategies in addressing these gaps are proposed, such as complex systems approaches to link processes across time scales, long-term experiments on physical-chemical-biological process interactions, and a focus on connectivity and patterns across spatial scales. It is suggested that these strategies will stimulate new research that coherently addresses the issues across hydrology, soil and agricultural sciences, forest engineering, forest ecology, and geomorphology.
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We present a method for the rapid determination of methane emissions from landfills based on atmospheric dispersion theory, which suggests that the methane concentration, at a small distance from the soil/atmosphere interface, is proportional to its flux. Thus, after suitable calibration, the determination of methane concentrations close to the ground allows for flux determination in a shorter time than with standard enclosure techniques. This concept was tested using a surface probe in direct contact with the ground. The probe extracts a continuous sample of the air at the probe/ground interface and transports it to a portable methane analyzer. It was observed that stable methane concentrations were measured 30 s after the probe was positioned at the measurement point. These concentrations correlated well with the fluxes measured by standard static chambers. The method was used to determine the fluxes at 217 points within a 90,000 m(2) landfill. These measurements facilitated mapping of the CH4 emissions and the localization of hotspots. We conclude that the method is simple, effective, and relatively quick, compared to existing standard methods.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Metano/análisis , Eliminación de Residuos , Suelo/química , Instalaciones de Eliminación de Residuos , AtmósferaRESUMEN
INTRODUCTION AND OBJECTIVES: A Consensus document on the management of patients with neurogenic detrusor overactivity (NDO) was published in 2018. The present document aims to update its recommendations regarding treatment considering the new evidence available, and to contribute to the standardization of the management of this disorder. METHODS: The methodology used was based on a systematic review and the Nominal Group Technique. The clinical coordinator (CC) and the Consensus update group (CUG) defined the questions to be updated and carried out a systematic review to identify the new available evidence. After being evaluated by the expert panel, the relevant recommendations were updated and agreed in a consensus meeting. RESULTS: A total of 3210 publications were identified and 26 publications that met the inclusion criteria were included. The CUG updated 18 recommendations on the therapeutic approach to NDO. Unanimous consensus was reached on all of them. CONCLUSIONS: Previous recommendations need to be revised due to the availability of new drugs, the increasing evidence on the use of botulinum toxin or neuromodulation procedures, and new surgical options.
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INTRODUCTION: Patient safety is paramount in providing quality healthcare and constitutes a global concern for healthcare systems. Radioiodine treatment to patients with well-differentiated thyroid cancer is not without risks. The aim of this study is to identify, evaluate and mitigate the risks associated with this procedure. MATERIALS AND METHODS: A single-centre descriptive study was conducted in which risk management was carried out by establishing a risk map using FMEA methodology. RESULTS: Based on the process map 6 sub-processes and 23 failure modes in the three phases of the treatment process were analysed. According to risk priority number (RPN), the sub-process with the highest risk was administrative management (RPN 82), followed by treatment per se and post-treatment imaging (both with RPN 70). An overall process RPN of 300 (156 pre-treatment, 74 treatment and 70 post-treatment) was obtained. Failures directly related to the patient pose a high risk. The implementation of verification systems, performing tasks earlier and providing quality medical information are the most relevant preventive measures to be implemented. CONCLUSIONS: The application of the FMEA methodology in the risk management for radioiodine treatment is a valuable tool for improving the quality and safety of this process. The risk map has been able to identify failures at different stages, assess their causes and effects, prioritise the risks identified and implement preventive and corrective measures that can be monitored, ensuring the effectiveness of the actions taken.
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Radioisótopos de Yodo , Gestión de Riesgos , Neoplasias de la Tiroides , Radioisótopos de Yodo/uso terapéutico , Humanos , Neoplasias de la Tiroides/radioterapia , Seguridad del Paciente , Análisis de Modo y Efecto de Fallas en la Atención de la SaludRESUMEN
Intragastric infection mimics the natural route of infection of Chlamydia abortus (etiological agent of ovine enzootic abortion). In the mouse model, intragastric experimental infection induces very mild signs of infection followed by late term abortions, as it is shown by the natural ovine host. In order to evaluate the immune mechanisms associated to the dissemination of the pathogen from the gastrointestinal tract, we have administered an intragastric dose of C. abortus to pregnant mice. Systemic and local expression of cytokines, tissue colonization and excretion of bacteria after parturition were monitored during pregnancy. Susceptible CBA/J mice showed a higher bacterial colonization of the placenta and excretion of live bacteria after parturition that were related to a higher local IL-10 expression. By contrast, resistant C57BL/6 mouse strain had higher local IFN-γ mRNA expression in the placenta just before parturition and a transient bacterial colonization of the reproductive tract, with no excretion of C. abortus after parturition. In summary, intragastric infection not only mimics the natural route of infection of C. abortus, but can also be useful in order to understand the immunopathogenesis of chlamydial abortion in the mouse.
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Aborto Séptico/inmunología , Infecciones por Chlamydia/complicaciones , Infecciones por Chlamydia/inmunología , Modelos Animales de Enfermedad , Interferón gamma/metabolismo , Placenta/inmunología , Complicaciones Infecciosas del Embarazo/inmunología , Aborto Séptico/prevención & control , Animales , Femenino , Interferón gamma/genética , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , EmbarazoRESUMEN
The wide distribution and ecological plasticity of the red fox (Vulpes vulpes) make it a potential reservoir for many infectious diseases shared with domestic and wild carnivores. One of such diseases is canine distemper, which is caused by an RNA virus and its main domestic reservoir is the dog. However, other carnivores can also participate in its maintenance, as shown by the recent upsurge of reported cases in wildlife in many parts of the world, and by the fact that red foxes may act as true reservoirs for canine distemper virus (CDV). The lack of validated serological tests for wildlife or other non-target species may be a handicap for monitoring this virus. In this study, serological assays were compared in 147 red fox sera using a commercial ELISA validated for its use in dogs and a non-specific modified ELISA with Protein A peroxidase conjugate to detect bound antibodies. In addition, the presence of CDV RNA in brain, spleen, lung, and liver samples from 144 foxes was investigated by a RT-qPCR. Through the comparison of the results of both ELISAs and the use of a finite mixture model of the optical density values obtained by both techniques, we adjusted the cut-off point of the commercial ELISA to obtain the seroprevalence in foxes. The overall seroprevalence detected was 53.7% (79/147) and 57.1% (84/147) by the commercial and modified ELISA, respectively, with a moderate agreement according to Cohen's Kappa statistic (κ = 0.491, z = 5.97, p < 0.0001). CDV RNA was detected in 30 out of 144 foxes, which resulted in 20.8% of CDV-infected foxes. At individual level, the results obtained by relating the serological status and the presence/absence of RNA in different organs were explained in terms of the pathogenesis of the infection. Our results highlight the convenience of adjusting the cut-off point when using an ELISA assay developed in domestic dogs for its use in foxes. Moreover, Protein A is confirmed to be a good alternative to be used in red foxes, presenting a good reactivity towards its IgG.
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Carnívoros , Virus del Moquillo Canino , Moquillo , Enfermedades de los Perros , Animales , Perros , Zorros/genética , Virus del Moquillo Canino/genética , Estudios Seroepidemiológicos , Animales Salvajes , Moquillo/diagnóstico , Moquillo/epidemiología , Carnívoros/genética , Ensayo de Inmunoadsorción Enzimática/veterinaria , ARNRESUMEN
Background: Dyskeratosis congenita (DC) is a multisystem and ultra-rare hereditary disease characterized by somatic involvement, bone marrow failure, and predisposition to cancer. The main objective of this study is to describe the natural history of DC through a cohort of patients diagnosed in childhood and followed up for a long period of time. Material and methods: Multicenter, retrospective, longitudinal study conducted in patients followed up to 24 years since being diagnosed in childhood (between 1998 and 2020). Results: Fourteen patients were diagnosed with DC between the ages of 3 and 17 years (median, 8.5 years). They all had hematologic manifestations at diagnosis, and nine developed mucocutaneous manifestations during the first decade of life. Seven presented severe DC variants. All developed non-hematologic manifestations during follow-up. Mutations were identified in 12 patients. Thirteen progressed to bone marrow failure at a median age of 8 years [range, 3-18 years], and eight received a hematopoietic stem cell transplant. Median follow-up time was 9 years [range, 2-24 years]. Six patients died, the median age was 13 years [range, 6-24 years]. As of November 2022, eight patients were still alive, with a median age of 18 years [range, 6-32 years]. None of them have developed myeloblastic syndrome or cancer. Conclusions: DC was associated with high morbidity and mortality in our series. Hematologic manifestations appeared early and consistently. Non-hematologic manifestations developed progressively. No patient developed cancer possibly due to their young age. Due to the complexity of the disease multidisciplinary follow-up and adequate transition to adult care are essential.
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Ante-mortem diagnosis of caprine tuberculosis, as in other ruminant species, is a complex process. Therefore, it is sometimes necessary to apply a combination of methods that increases the sensitivity of diagnosis while maintaining adequate specificity. In the present study, we analysed the use of ELISA based on a double-recognition methodology for the diagnosis of goat tuberculosis. Serum samples from animals with tuberculosis, confirmed by histopathological studies and presence of Ziehl-Neelsen-positive bacteria in the lesions, were used to assess sensitivity. Sera from flocks without tuberculosis were used to assess diagnostic specificity. The relationship between ELISA results and the type of tuberculous lesions, both macroscopic and microscopic, was analysed. The sensitivity and specificity of ELISA test were 69.9% and 97.9%, respectively. Sensitivity was higher in animals with macroscopic lesions, indicating more advanced forms of the disease. Similarly, a higher sensitivity was found in animals with microscopic lesions associated with active tuberculosis, such as cavitary lesions.
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Enfermedades de las Cabras , Tuberculosis , Animales , Cabras , Enfermedades de las Cabras/microbiología , Tuberculosis/diagnóstico , Tuberculosis/veterinaria , Tuberculosis/microbiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Sensibilidad y EspecificidadRESUMEN
The antifungal mode of action of chitosan has been studied for the last 30 years, but is still little understood. We have found that the plasma membrane forms a barrier to chitosan in chitosan-resistant but not chitosan-sensitive fungi. The plasma membranes of chitosan-sensitive fungi were shown to have more polyunsaturated fatty acids than chitosan-resistant fungi, suggesting that their permeabilization by chitosan may be dependent on membrane fluidity. A fatty acid desaturase mutant of Neurospora crassa with reduced plasma membrane fluidity exhibited increased resistance to chitosan. Steady-state fluorescence anisotropy measurements on artificial membranes showed that chitosan binds to negatively charged phospholipids that alter plasma membrane fluidity and induces membrane permeabilization, which was greatest in membranes containing more polyunsaturated lipids. Phylogenetic analysis of fungi with known sensitivity to chitosan suggests that chitosan resistance may have evolved in nematophagous and entomopathogenic fungi, which naturally encounter chitosan during infection of arthropods and nematodes. Our findings provide a method to predict the sensitivity of a fungus to chitosan based on its plasma membrane composition, and suggests a new strategy for antifungal therapy, which involves treatments that increase plasma membrane fluidity to make fungi more sensitive to fungicides such as chitosan.
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Antifúngicos/farmacología , Quitosano/farmacología , Hongos/efectos de los fármacos , Hongos/metabolismo , Antifúngicos/metabolismo , Membrana Celular/metabolismo , Quitosano/metabolismo , Ácidos Grasos Insaturados/metabolismo , Polarización de Fluorescencia , Hongos/citología , Fluidez de la Membrana/efectos de los fármacos , Fosfolípidos/metabolismoRESUMEN
It has been suggested that oxidative stress may participate in the progression of diabetes and its complications. Long-term complications of type 2 diabetes mellitus (T2DM) include retinopathy, atherosclerosis, shortened life span of erythrocytes, nephropathy, and chronic kidney disease (CKD). Oxidative damage has been associated with erythrocyte apoptosis induction in other pathological conditions. Our aim was to study the presence of eryptosis and its possible relationship with oxidative damage in patients with T2DM without CKD (T2DM/CKD(-)) and in patients with T2DM and CKD (T2DM/CKD(+)).Oxidative damage of lipids erythrocytes were increased in diabetic patients. The highest lipoperoxidation was found in T2DM/CKD(+). Likewise, the lower plasma total antioxidant capacity, GSH/GSSG ratio, and GSH in erythrocytes were found in T2DM/CKD(+) patients. A negative correlation was found between plasma total antioxidant capacity and oxidative damage. Phosphatidylserine (PS) externalization was measured in erythrocytes to evaluate eryptosis. Annexin binding in erythrocytes of T2DM/CKD(+) patients was higher than in healthy subjects and T2DM/CKD(-) patients. A positive correlation between lipoperoxidation and PS externalization in erythrocytes was found. This work showed that the erythrocytes of diabetic patients have increased oxidative damage, a reduction of antioxidant systems and more erythrocyte PS externalization. The duration of diabetes and the presence of CKD increase both oxidative damage and eryptosis. It is possible that a longer time of evolution induces an increase in erythrocyte oxidative damage and the consumption of blood antioxidant systems, adding to the osmotic stress in CKD and so contributes to an increase in PS externalization in diabetic patients.
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Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Fallo Renal Crónico/etiología , Fallo Renal Crónico/metabolismo , Estrés Oxidativo , Fosfatidilserinas/metabolismo , Adulto , Anexinas/sangre , Antioxidantes/análisis , Antioxidantes/metabolismo , Apoptosis , Progresión de la Enfermedad , Eritrocitos/metabolismo , Femenino , Glutatión/sangre , Glutatión/metabolismo , Glutatión Peroxidasa/sangre , Glutatión Peroxidasa/metabolismo , Humanos , Peroxidación de Lípido/fisiología , Masculino , Malondialdehído/sangre , Malondialdehído/metabolismo , Persona de Mediana Edad , Oxidación-Reducción , Fosfatidilserinas/sangre , Superóxido Dismutasa/sangre , Superóxido Dismutasa/metabolismoRESUMEN
Using a set of large eddy point-particle simulations, we explore the fluid dynamics of an ejected puff resulting from a cough/sneeze. The ejection contains over 61 000 potentially virus-laden droplets at an injection Reynolds number of about 46 000, comparable to an actual cough/sneeze. We observe that global puff properties, such as centroid, puff volume, momentum, and buoyancy vary little across realizations. Other properties, such as maximum extent, shape, and edge velocity of the puff, may exhibit substantial variation. In many realizations, a portion of the puff splits off and advances along a random direction, while keeping airborne droplet nuclei afloat. This peeled-off portion provides a mechanism for virus-laden droplets to travel over large distances in a short amount of time. We also observe that the vast majority of droplets remain suspended within the puff after all liquid has evaporated. The main objectives of the study are to (i) evaluate assumptions of Balachandar's et al. theory [Int. J. Multiphase Flow 132, 103439 (2020)], which include buoyancy effects, shape of the puff, and droplet evaporation rate, (ii) obtain values of closure parameters, which include location and time of the virtual origin, and puff entrainment and drag coefficients, and (iii) evaluate the accuracy of the theory in predicting the shape, size, and location of the puff, as well as droplet number density long after ejection. The theory adequately predicts global puff properties including size, velocity, and distance traveled, the largest size of droplets that exit the puff due to settling, and the droplet size distribution within the puff long after ejection.
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In this work, dimensional analysis is used to develop a general mathematical model to predict bulk density of SLMed components taking volumetric energy density, scanning speed, powder's thermal conductivity, specific heat capacity, and average grain diameter as independent variables. Strong relation between dependent and independent dimensionless products is observed. Inconel 718 samples were additively manufactured and a particular expression, in the form of a power-law polynomial, for its bulk density, in the working domain of the independent dimensionless product, was obtained. It is found that with longer laser exposure time, and lower scanning speed, better densification is attained. Likewise, volumetric energy density has a positive influence on bulk density. The negative effect of laser power in bulk density is attributed to improper process conditions leading to powder particle sublimation and ejection. A maximum error percentage between experimental and predicted bulk density of 3.7119% is achieved, which corroborates the accuracy of our proposed model. A general expression for determining the scanning speed, with respect to laser power, needed to achieve highly dense components, was derived. The model's applicability was further validated considering SLMed samples produced by AlSi10Mg and Ti6Al4V alloys. This article elucidates how to tune relevant manufacturing parameters to produce highly dense SLM parts using mathematical expressions derived from Buckingham's π- theorem.
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We describe an unusual case of axillary vein thrombosis after extensive muscular and fibrillar rupture of the long tendon of the right biceps brachii in a 43-year-old patient after an effort. The difficult diagnosis of this condition requires high suspicion and early treatment.
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Vena Axilar , Esfuerzo Físico , Traumatismos de los Tendones/complicaciones , Trombosis Venosa Profunda de la Extremidad Superior/etiología , Adulto , Vena Axilar/diagnóstico por imagen , Humanos , Masculino , Rotura/complicaciones , Rotura/diagnóstico por imagen , Traumatismos de los Tendones/diagnóstico por imagen , Ultrasonografía , Trombosis Venosa Profunda de la Extremidad Superior/diagnóstico por imagenRESUMEN
INTRODUCTION AND AIMS: Laparoscopic sleeve gastrectomy (LSG) is the most widely performed bariatric surgery worldwide but complications and failed procedures are on the rise. AIMS: To determine the reasons for failed LSGs and report the results of conversion to gastric bypass surgery, comparing the outcomes with those of primary gastric bypass surgery. MATERIALS AND METHODS: Patients with failed LSG that underwent conversion to gastric bypass surgery through a robotic-assisted and laparoscopic (hybrid) technique were evaluated. Outcomes and follow-up related to weight loss failure (WLF) were compared with those in patients that underwent primary laparoscopic gastric bypass (pLGB) surgery. RESULTS: Revisional surgery was performed on 13 patients due to WLF, on 3 patients because of refractory gastroesophageal reflux disease (GERD), and on 2 patients due to gastric stricture. There were no differences between the preoperative characteristics of the patients with WLF before undergoing conversion to gastric bypass and the patients that underwent pLGB surgery. At postoperative month 36, the percentage of excess weight loss was greater in the patients that underwent pLGB surgery, than in those with WLF that underwent conversion to gastric bypass (69.17±23.73 vs. 54.17±12.48, respectively; P<0.05). Refractory GERD, symptoms due to gastric stricture, and comorbidities all improved after the revisional surgery. CONCLUSION: Revisional surgery resulted in acceptable weight loss at 36 months of follow-up and favored comorbidity remission. In addition, it resolved symptoms of refractory GERD and gastric stricture.