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1.
medRxiv ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38883729

RESUMEN

Spinal muscular atrophy (SMA) is a neurodegenerative disease characterized by a varying degree of severity that correlates with the reduction of SMN protein levels. Motor neuron degeneration and skeletal muscle atrophy are hallmarks of SMA, but it is unknown whether other mechanisms contribute to the spectrum of clinical phenotypes. Here, through a combination of physiological and morphological studies in mouse models and SMA patients, we identify dysfunction and loss of proprioceptive sensory synapses as key signatures of SMA pathology. We demonstrate that SMA patients exhibit impaired proprioception, and their proprioceptive sensory synapses are dysfunctional as measured by the neurophysiological test of the Hoffmann reflex (H-reflex). We further show that loss of excitatory afferent synapses and altered potassium channel expression in SMA motor neurons are conserved pathogenic events found in both severely affected patients and mouse models. Lastly, we report that improved motor function and fatigability in ambulatory SMA patients and mouse models treated with SMN-inducing drugs correlate with increased function of sensory-motor circuits that can be accurately captured by the H-reflex assay. Thus, sensory synaptic dysfunction is a clinically relevant event in SMA, and the H-reflex is a suitable assay to monitor disease progression and treatment efficacy of motor circuit pathology.

2.
Clin Epigenetics ; 16(1): 71, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802956

RESUMEN

BACKGROUND: Methylation of serotonin-related genes has been proposed as a plausible gene-by-environment link which may mediate environmental stress, depressive and anxiety symptoms. DNA methylation is often measured in blood cells, but little is known about the association between this peripheral epigenetic modification and brain serotonergic architecture. Here, we evaluated the association between whole-blood-derived methylation of four CpG sites in the serotonin transporter (SLC6A4) and six CpG sites of the tryptophan hydroxylase 2 (TPH2) gene and in-vivo brain levels of serotonin transporter (5-HTT) and serotonin 4 receptor (5-HT4) in a cohort of healthy individuals (N = 254) and, for 5-HT4, in a cohort of unmedicated patients with depression (N = 90). To do so, we quantified SLC6A4/TPH2 methylation using bisulfite pyrosequencing and estimated brain 5-HT4 and 5-HTT levels using positron emission tomography. In addition, we explored the association between SLC6A4 and TPH2 methylation and measures of early life and recent stress, depressive and anxiety symptoms on 297 healthy individuals. RESULTS: We found no statistically significant association between peripheral DNA methylation and brain markers of serotonergic neurotransmission in patients with depression or in healthy individuals. In addition, although SLC6A4 CpG2 (chr17:30,236,083) methylation was marginally associated with the parental bonding inventory overprotection score in the healthy cohort, statistical significance did not remain after accounting for blood cell heterogeneity. CONCLUSIONS: We suggest that findings on peripheral DNA methylation in the context of brain serotonin-related features should be interpreted with caution. More studies are needed to rule out a role of SLC6A4 and TPH2 methylation as biomarkers for environmental stress, depressive or anxiety symptoms.


Asunto(s)
Encéfalo , Metilación de ADN , Depresión , Epigénesis Genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Serotonina , Transmisión Sináptica , Triptófano Hidroxilasa , Humanos , Metilación de ADN/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Masculino , Femenino , Adulto , Triptófano Hidroxilasa/genética , Serotonina/metabolismo , Serotonina/sangre , Encéfalo/metabolismo , Depresión/genética , Depresión/metabolismo , Epigénesis Genética/genética , Transmisión Sináptica/genética , Islas de CpG/genética , Persona de Mediana Edad , Adulto Joven , Receptores de Serotonina 5-HT4/genética , Receptores de Serotonina 5-HT4/metabolismo , Tomografía de Emisión de Positrones , Estudios de Cohortes
3.
Environ Res ; 251(Pt 1): 118611, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38452916

RESUMEN

This work evaluates the use of Echeveria elegans as a biomonitor of metals and radionuclides, using semi-urban soils as a study area. The study area is exposed to various trace elements of concern for various social groups in nearby localities. The quantification of metals and radionuclides was performed by X-ray fluorescence spectrometry and gamma spectrometry, respectively. Cumulative frequency distribution curves, descriptive statistics, and multivariate analysis were used to estimate the local geochemical baseline and identify geochemical and anthropogenic patterns of metals and radionuclides from topsoil and E. elegans. The evaluation of contaminants and the contribution of possible exposure routes (topsoil and atmospheric deposition) was performed with the enrichment factor (EF) and the relative concentration factor (CFR). The results suggest that the plant does not present significant physical stress due to the environmental conditions to which it was exposed. Likewise, it can bioaccumulate heavy metals from natural and anthropogenic sources. The quantification of radionuclides in the plant is below the detection limits, indicating a low bioavailability and transfer factor. The CFR and EF results showed that the plant accumulates metals from the topsoil and atmospheric deposition. The bioaccumulation mechanism would be related to the functioning of Crassulaceae Acid Metabolism (CAM). In topsoil, the organic acids of the plant would modify the solubility of the metals present in an insoluble form in the soil, acting as ligands and, subsequently, following the transport route of these metabolites. In atmospheric deposition, the metals deposited in the leaves would be incorporated into the plant through the opening of the stomata because of the capture of CO2 (at night, day, or during environmental stress) by the CAM. Overall, the evidence showed that the succulent can be used as a biomonitor of heavy metals. However, additional studies are required to determine its usefulness as a radionuclide biomonitor.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados , Radioisótopos , Contaminantes del Suelo , Metales Pesados/análisis , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Radioisótopos/análisis , Suelo/química , Espectrometría por Rayos X
4.
Phys Rev E ; 109(1-1): 014107, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38366493

RESUMEN

One of the main issues that real energy converters present, when they produce effective work, is the inevitable entropy production. Within the context of nonequilibrium thermodynamics, entropy production tends to energetically degrade human-made or living systems. On the other hand, it is not useful to think about designing an energy converter that works in the so-called minimum entropy production regime since the effective power output and efficiency are zero. In this paper we establish some energy conversion theorems similar to Prigogine's theorem with constrained forces. The purpose of these theorems is to reveal trade-offs between design and the so-called operation modes for (2×2)-linear isothermal energy converters. The objective functions that give rise to those thermodynamic constraints show stability. A two-mesh electric circuit was built as an example to demonstrate the theorems' validity. Likewise, we reveal a type of energetic hierarchy for power output, efficiency, and dissipation function when the circuit is tuned to any of the operating regimes studied here. These are maximum power output (MPO), maximum efficient power (MPη), maximum omega function (MΩ), maximum ecological function (MEF), maximum efficiency (Mη), and minimum dissipation function (mdf).

5.
J Chem Phys ; 159(14)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37815111

RESUMEN

The dynamics of a tracer particle in a bath of quasi-hard colloidal spheres is studied by Langevin dynamics simulations and mode coupling theory (MCT); the tracer radius is varied from equal to up to seven times larger than the bath particles radius. In the simulations, two cases are considered: freely diffusing tracer (passive microrheology) and tracer pulled with a constant force (active microrheology). Both cases are connected by linear response theory for all tracer sizes. It links both the stationary and transient regimes of the pulled tracer (for low forces) with the equilibrium correlation functions; the velocity of the pulled tracer and its displacement are obtained from the velocity auto-correlation function and the mean squared displacement, respectively. The MCT calculations give insight into the physical mechanisms: At short times, the tracer rattles in its cage of neighbours, with the frequency increasing linearly with the tracer radius asymptotically. The long-time tracer diffusion coefficient from passive microrheology, which agrees with the inverse friction coefficient from the active case, arises from the transport of transverse momentum around the tracer. It can be described with the Brinkman equation for the transverse flow field obtained in extension of MCT, but cannot be recovered from the MCT kernel coupling to densities only. The dynamics of the bath particles is also studied; for the unforced tracer the dynamics is unaffected. When the tracer is pulled, the velocity field in the bath follows the prediction of the Brinkman model, but different from the case of a Newtonian fluid.

6.
Phys Rev E ; 108(1-1): 014123, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37583186

RESUMEN

This work uses the low-dissipation strategy to obtain efficiency at maximum power from a stochastic heat engine performing Carnot-, Stirling- and Ericsson-like cycles at finite time. The heat engine consists of a colloidal particle trapped by optical tweezers, in contact with two thermal baths at different temperatures, namely hot (T_{h}) and cold (T_{c}). The particle dynamics is characterized by a Langevin equation with time-dependent control parameters bounded to a harmonic potential trap. In a low-dissipation approach, the equilibrium properties of the system are required, which in our case, can be calculated through a statelike equation for the mean value 〈x^{2}〉_{eq} coming from a macroscopic expression associated with the Langevin equation.

7.
Data Brief ; 48: 109269, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37383780

RESUMEN

This data article presents a simulation model based on quantum mechanics and energy potentials for obtaining simulation data that allows, from the perspective of materials informatics, the prediction of the electrodeposition mechanism for forming nanostructured metallic coatings. The development of the research is divided into two parts i) the formulation (Quantum mechanical model and Corrected model for electron prediction; using a modified Schrödinger equation) and ii) the implementation of the theoretical prediction model (Discretization of the model). For the simulation process, the finite element method (FEM) was used considering the equation of electric potential and electroneutrality with and without the inclusion of quantum leap. We also provide the code to perform QM simulations in CUDA®, and COMSOL® software, the simulation parameters, and data for two metallic arrangements of chromium nanoparticles (CrNPs) electrodeposited on commercial steel substrate. (CrNPs-AISI 1020 steel and CrNPs-A618 steel). Data collection shows the direct relationship between applied potential (VDC), current (A), concentration (ppm), and time (s) for the homogeneous formation of the coating during the electrodeposition process, as estimated by the theoretical model developed. Their potential reuse data is done to establish the precision of the theoretical model in predicting the formation and growth of nanostructured surface coatings with metallic nanoparticles to give surface-mechanical properties.

8.
Blood ; 140(13): 1482-1495, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-35820055

RESUMEN

Molecular programs initiating cell fate divergence (CFD) are difficult to identify. Current approaches usually compare cells long after CFD initiation, therefore missing molecular changes at its start. Ideally, single cells that differ in their CFD molecular program but are otherwise identical are compared early in CFD. This is possible in diverging sister cells, which were identical until their mother's division and thus differ mainly in CFD properties. In asymmetrically dividing cells, divergent daughter fates are prospectively committed during division, and diverging sisters can thus be identified at the start of CFD. Using asymmetrically dividing blood stem cells, we developed a pipeline (ie, trackSeq) for imaging, tracking, isolating, and transcriptome sequencing of single cells. Their identities, kinship, and histories are maintained throughout, massively improving molecular noise filtering and candidate identification. In addition to many identified blood stem CFD regulators, we offer here this pipeline for use in CFDs other than asymmetric division.


Asunto(s)
Rastreo Celular , Células Madre , Diferenciación Celular , División Celular
9.
J Prev Alzheimers Dis ; 9(3): 425-434, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35841243

RESUMEN

BACKGROUND: There are currently no drug therapies modifying the natural history of patients suffering Alzheimer's disease (AD). Most recent clinical trials in the field include only subjects in early stage of the disease, while patients with advanced AD are usually not represented. OBJECTIVES: To evaluate the feasibility, safety and efficacy of systemic infusions of adenosine triphosphate (ATP) in patients with moderate to severe AD, and to select the minimum effective dose of infusion. DESIGN: A phase IIb, randomized, double-blind, placebo-controlled clinical trial investigates. PARTICIPANTS: A total of 20 subjects with moderate or severe AD were included, 16 in the treatment group and 4 in the placebo group (4:1 randomization) at two dosage regimens, 6-hour or 24-hour infusions. RESULTS: The proof-of-concept study was successfully conducted, with no significant deviations from the study protocol and no serious adverse events reported. Regarding efficacy, only marginal differences were observed between ATP and placebo arms for H-MRS and MMSE variables. CONCLUSIONS: Our study demonstrates that the use of ATP infusion as therapy is feasible and safe. Larger studies are however needed to assess the efficacy of ATP in moderate to severe AD.


Asunto(s)
Enfermedad de Alzheimer , Adenosina Trifosfato/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Método Doble Ciego , Estudios de Factibilidad , Humanos , Infusiones Intravenosas
10.
Artículo en Español | IBECS | ID: ibc-211473

RESUMEN

Cuando pensamos en nodriza, las dos palabras que se vienen a la cabeza son leche materna y altruismo. Dos vocablos que han estado ligados a ellas y que hoy, en el siglo XXI, aún continúan. Las primeras nodrizas hicieron de esto una forma de trabajo, no estaba remunerado y para la clase alta era una forma de librarse del cuidado y crianza de sus hijos. Para las nodrizas supuso la incorporación al mundo laboral [Fragmento de texto] (AU)


Asunto(s)
Humanos , Femenino , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Bancos de Leche Humana/historia , Maternidades/historia , España
11.
Alzheimers Res Ther ; 13(1): 141, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404456

RESUMEN

BACKGROUND: To explore whether the combination of white matter hyperintensities (WMHs) and amyloid-beta (Aß) deposition is associated with worse cognitive performance on cognitive composites (CCs) domain scores in individuals with subjective cognitive decline (SCD). METHODS: Two hundred participants from the FACEHBI cohort underwent structural magnetic resonance imaging (MRI), 18F-florbetaben positron emission tomography (FBB-PET), and neuropsychological assessment. WMHs were addressed through the Fazekas scale, the Age-Related White Matter Changes (ARWMC) scale, and the FreeSurfer pipeline. Eight CCs domain scores were created using the principal component analysis (PCA). Age, sex, education, and apolipoprotein E (APOE) were used as adjusting variables. RESULTS: Adjusted multiple linear regression models showed that FreeSurfer (B - .245; 95% CI - .1.676, - .393, p = .016) and ß burden (SUVR) (B - .180; 95% CI - 2.140, - .292; p = .070) were associated with face-name associative memory CCs domain score, although the latest one was not statistically significant after correction for multiple testing (p = .070). There was non-significant interaction of these two factors on this same CCs domain score (p = .54). However, its cumulative effects on face-name associative performance indicated that those individuals with either higher WMH load or higher Aß burden showed the worst performance on the face-name associative memory CCs domain score. CONCLUSIONS: Our results suggest that increased WMH load and increased Aß are independently associated with poorer episodic memory performance in SCD individuals, indicating a cumulative effect of the combination of these two pathological conditions in promoting lower cognitive performance, an aspect that could help in terms of treatment and prevention.


Asunto(s)
Disfunción Cognitiva , Sustancia Blanca , Péptidos beta-Amiloides/metabolismo , Cognición , Disfunción Cognitiva/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Sustancia Blanca/diagnóstico por imagen
12.
AJNR Am J Neuroradiol ; 42(6): 1008-1016, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33707278

RESUMEN

PURPOSE: Our aim was to study the association between abnormal findings on chest and brain imaging in patients with coronavirus disease 2019 (COVID-19) and neurologic symptoms. MATERIALS AND METHODS: In this retrospective, international multicenter study, we reviewed the electronic medical records and imaging of hospitalized patients with COVID-19 from March 3, 2020, to June 25, 2020. Our inclusion criteria were patients diagnosed with Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection with acute neurologic manifestations and available chest CT and brain imaging. The 5 lobes of the lungs were individually scored on a scale of 0-5 (0 corresponded to no involvement and 5 corresponded to >75% involvement). A CT lung severity score was determined as the sum of lung involvement, ranging from 0 (no involvement) to 25 (maximum involvement). RESULTS: A total of 135 patients met the inclusion criteria with 132 brain CT, 36 brain MR imaging, 7 MRA of the head and neck, and 135 chest CT studies. Compared with 86 (64%) patients without acute abnormal findings on neuroimaging, 49 (36%) patients with these findings had a significantly higher mean CT lung severity score (9.9 versus 5.8, P < .001). These patients were more likely to present with ischemic stroke (40 [82%] versus 11 [13%], P < .0001) and were more likely to have either ground-glass opacities or consolidation (46 [94%] versus 73 [84%], P = .01) in the lungs. A threshold of the CT lung severity score of >8 was found to be 74% sensitive and 65% specific for acute abnormal findings on neuroimaging. The neuroimaging hallmarks of these patients were acute ischemic infarct (28%), intracranial hemorrhage (10%) including microhemorrhages (19%), and leukoencephalopathy with and/or without restricted diffusion (11%). The predominant CT chest findings were peripheral ground-glass opacities with or without consolidation. CONCLUSIONS: The CT lung disease severity score may be predictive of acute abnormalities on neuroimaging in patients with COVID-19 with neurologic manifestations. This can be used as a predictive tool in patient management to improve clinical outcome.


Asunto(s)
Encéfalo/diagnóstico por imagen , COVID-19/diagnóstico por imagen , COVID-19/patología , Pulmón/diagnóstico por imagen , Adulto , Anciano , Encéfalo/patología , COVID-19/complicaciones , Humanos , Pulmón/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neuroimagen , Prevalencia , Estudios Retrospectivos , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X/métodos
13.
Chemosphere ; 266: 128968, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33246699

RESUMEN

In the present study, microplastics (MPs) and metal concentrations were studied in the widely consumed tilapia (Oreochromis niloticus) fishes (n = 15) collected from a metropolitan reservoir of the Atoyac River basin, Mexico. Nearly 139 fibers were extracted from the gastrointestinal tracts and assessed using optical microscopy to evaluate their physical characteristics. The colour distribution of the fibers was mainly black (40%), blue (19%), red and white (14%). SEM images represented the surface morphology, while the elemental composition of the fibers was studied using EDX spectra. Polymer characterization using µFTIR aided in confirming the fibers as plastics (polyamide, polyester, and synthetic cellulose) and non-plastics (natural cellulose). Henceforth, ∼33% of the fibers, provisionally thought to be plastics, were natural fibers. The total metal concentrations were higher in the liver (259.24 mg kg-1) than the muscle (122.56 mg kg-1) due to diverse metabolic functions in the hepatic tissues. Human health risk assessment in terms of Hazard Index (HI) presented Pb and Zn values above unity in both adults and children, prompting regulatory measures. Statistical tests between MPs and fish biometry did not present any substantial correlations. The present study also affirmed that the presence of MPs and metals in fishes of a highly contaminated region is not only governed by their bioavailabilities, but also on the physiological characteristics of the individual organism.


Asunto(s)
Cíclidos , Tilapia , Contaminantes Químicos del Agua , Animales , Niño , Monitoreo del Ambiente , Agua Dulce , Humanos , México , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
14.
Phys Rev E ; 101(5-1): 052607, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32575230

RESUMEN

The analysis of the dynamics of tracer particles in a complex bath can provide valuable information about the microscopic behavior of the bath. In this work, we study the dynamics of a forced tracer in a colloidal bath by means of Langevin dynamics simulations and a theory model within continuum mechanics. In the simulations, the bath is comprised of quasihard spheres with a volume fraction of 50% immersed in a featureless quiescent solvent, and the tracer is pulled with a constant small force (within the linear regime). The theoretical analysis is based on the Navier-Stokes equation, where a term proportional to the velocity arises from coarse-graining the friction of the colloidal particles with the solvent. As a result, the final equation is similar to the Brinkman model, although the interpretation is different. A length scale appears in the model, k_{0}^{-1}, where the transverse momentum transport crosses over to friction with the solvent. The effective friction coefficient experienced by the tracer grows with the tracer size faster than the prediction from Stokes's law. Additionally, the velocity profiles in the bath decay faster than in a Newtonian fluid. The comparison between simulations and theory points to a boundary condition of effective partial slip at the tracer surface. We also study the fluctuations in the tracer position, showing that it reaches diffusion at long times, with a subdiffusive regime at intermediate times. The diffusion coefficient, obtained from the long-time slope of the mean-squared displacement, fulfills the Stokes-Einstein relation with the friction coefficient calculated from the steady tracer velocity, confirming the validity of the linear response formalism.

15.
Eur Neuropsychopharmacol ; 36: 154-159, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32522387

RESUMEN

A polymorphism in the gene encoding the serotonin (5-HT) transporter (5-HTT) has been shown to moderate the response to CO2 inhalation, an experimental model for panic attacks (PAs). Recurrent, unpredictable PAs represent, together with anticipatory anxiety of recurring attacks, the core feature of panic disorder (PD) and significantly interfere with patients' daily life. In addition to genetic components, accumulating evidence suggests that epigenetic mechanisms, which regulate gene expression by modifying chromatin structure, also play a fundamental role in the etiology of mental disorders. However, in PD, epigenetic mechanisms have barely been examined to date. In the present study, we investigated the relationship between methylation at the regulatory region of the gene encoding the 5-HTT and the reactivity to a 35% CO2 inhalation in PD patients. We focused on four specific CpG sites and found a significant association between the methylation level of one of these CpG sites and the fear response. This suggests that the emotional response to CO2 inhalation might be moderated by an epigenetic mechanism, and underlines the implication of the 5-HT system in PAs. Future studies are needed to further investigate epigenetic alterations in PD and their functional consequences. These insights can increase our understanding of the underlying pathophysiology and support the development of new treatment strategies.


Asunto(s)
Dióxido de Carbono/efectos adversos , Metilación de ADN/fisiología , Miedo/fisiología , Trastorno de Pánico/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos/fisiología , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Adulto , Secuencia de Bases , Epigénesis Genética/efectos de los fármacos , Epigénesis Genética/fisiología , Miedo/efectos de los fármacos , Miedo/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastorno de Pánico/genética , Trastorno de Pánico/psicología , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética
16.
Rev. cir. (Impr.) ; 72(3): 245-249, jun. 2020.
Artículo en Español | LILACS | ID: biblio-1115550

RESUMEN

Resumen Introducción: Los tumores neuroendocrinos (TNE), son tumores compuestos por células productoras de péptidos y aminas. Los TNE gástricos, representan el 1% de todas las neoplasias, sin embargo su incidencia ha ido en aumento. Son generalmente asintomáticos y no funcionantes. El tratamiento es generalmente la resección local. Caso Clínico: paciente de 48 años con sospecha de cáncer gástrico; su estudio demuestra un TNE gástrico bien diferenciado tipo 1. Se realiza etapificación y se define en comité oncológico la vigilancia endoscópica. El hallazgo de un TNE, en el estudio de cáncer gástrico, es un hallazgo poco frecuente. Debido al aumento progresivo en la realización de endoscopías digestivas altas, secundario a la alta prevalencia de cáncer gástrico en nuestro país, se espera que aumenten hallazgos como un TNE. Es por esto que realizamos una revisión de la literatura y planteamos algunas conclusiones al respecto.


Introduction: Neuroendocrine tumors (NETs) are composed of cells that produce peptides and amines. Gastric NETs represent 1% of all neoplasms; however their incidence has been increasing. They are usually asymptomatic and non-functioning. The treatment is usually local resection. Case Report: We present the case of a 48-year-old patient who was suspected of gastric cancer; her study shows a well-differentiated type 1 gastric NET. Staging is performed and endoscopic surveillance is defined in the oncology board. The finding of a NET, in the study of gastric cancer, is a rare finding. Due to the progressive increase in the performance of upper gastrointestinal endoscopies, secondary to the high prevalence of gastric cancer in our country, it is expected to increase findings as a NET. That is why we conducted a review of the literature and made some conclusions about it.


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/etiología , Tumores Neuroendocrinos/terapia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/fisiopatología , Neoplasias Gástricas/terapia , Incidencia , Oncología Médica/métodos , Estadificación de Neoplasias
17.
Rev Med Chil ; 147(7): 887-890, 2019 Jul.
Artículo en Español | MEDLINE | ID: mdl-31859987

RESUMEN

BACKGROUND: The use of systemic chemotherapy has survival and palliation benefits in oncological patients. Mortality at 30 days after the administration of systemic chemotherapy is considered as a quality and safety indicator of oncological patient care. The international mortality threshold is 5%, which is the figure used to compare institutions. AIM: To assess mortality at 30 days after the administration of ambulatory systemic chemotherapy in a regional referral center in adult cancer patients. MATERIAL AND METHODS: Retrospective observational study of patients receiving ambulatory systemic chemotherapy in the oncology service of a regional public hospital during 2018. The 30-day mortality rate was calculated. Demographic characteristics, baseline disease and the treatment received were recorded. RESULTS: During the study period, 690 patients received ambulatory systemic chemotherapy. Chemotherapy was palliative in 76% of patients and 53% received a first line treatment. Seventeen (2.5%) died within 30 days of treatment administration. Nine deaths (52.9%) were definitely related to treatment and sepsis was the most frequent cause. CONCLUSIONS: Our mortality rates are similar to international data. This type of audit reviews local outcomes and identifies factors contributing to mortality aiming to improve standards of care.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias/tratamiento farmacológico , Neoplasias/mortalidad , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
18.
BMC Plant Biol ; 19(1): 458, 2019 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-31664901

RESUMEN

BACKGROUND: White root rot (WRR) disease caused by Rosellinia necatrix is one of the most important threats affecting avocado orchards in temperate regions. The eradication of WRR is a difficult task and environmentally friendly control methods are needed to lessen its impact. Priming plants with a stressor (biotic or abiotic) can be a strategy to enhance plant defense/tolerance against future stress episodes but, despite the known underlying common mechanisms, few studies use abiotic-priming for improving tolerance to forthcoming biotic-stress and vice versa ('cross-factor priming'). To assess whether cross-factor priming can be a potential method for enhancing avocado tolerance to WRR disease, 'Dusa' avocado rootstocks, susceptible to R. necatrix, were subjected to two levels of water stress (mild-WS and severe-WS) and, after drought-recovery, inoculated with R. necatrix. Physiological response and expression of plant defense related genes after drought-priming as well as the disease progression were evaluated. RESULTS: Water-stressed avocado plants showed lower water potential and stomatal limitations of photosynthesis compared to control plants. In addition, NPQ and qN values increased, indicating the activation of energy dissipating mechanisms closely related to the relief of oxidative stress. This response was proportional to the severity of the water stress and was accompanied by the deregulation of pathogen defense-related genes in the roots. After re-watering, leaf photosynthesis and plant water status recovered rapidly in both treatments, but roots of mild-WS primed plants showed a higher number of overexpressed genes related with plant defense than severe-WS primed plants. Disease progression after inoculating primed plants with R. necatrix was significantly delayed in mild-WS primed plants. CONCLUSIONS: These findings demonstrate that mild-WS can induce a primed state in the WRR susceptible avocado rootstock 'Dusa' and reveal that 'cross-factor priming' with water stress (abiotic stressor) is effective for increasing avocado tolerance against R. necatrix (biotic stressor), underpinning that plant responses against biotic and abiotic stress rely on common mechanisms. Potential applications of these results may involve an enhancement of WRR tolerance of current avocado groves and optimization of water use via low frequency deficit irrigation strategies.


Asunto(s)
Ascomicetos/fisiología , Sequías , Expresión Génica , Genes de Plantas , Persea/fisiología , Enfermedades de las Plantas/microbiología , Resistencia a la Enfermedad/fisiología , Persea/microbiología , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Estrés Fisiológico/genética
19.
Rev. méd. Chile ; 147(7): 887-890, jul. 2019. tab
Artículo en Español | LILACS | ID: biblio-1058618

RESUMEN

Background: The use of systemic chemotherapy has survival and palliation benefits in oncological patients. Mortality at 30 days after the administration of systemic chemotherapy is considered as a quality and safety indicator of oncological patient care. The international mortality threshold is 5%, which is the figure used to compare institutions. Aim: To assess mortality at 30 days after the administration of ambulatory systemic chemotherapy in a regional referral center in adult cancer patients. Material and Methods: Retrospective observational study of patients receiving ambulatory systemic chemotherapy in the oncology service of a regional public hospital during 2018. The 30-day mortality rate was calculated. Demographic characteristics, baseline disease and the treatment received were recorded. Results: During the study period, 690 patients received ambulatory systemic chemotherapy. Chemotherapy was palliative in 76% of patients and 53% received a first line treatment. Seventeen (2.5%) died within 30 days of treatment administration. Nine deaths (52.9%) were definitely related to treatment and sepsis was the most frequent cause. Conclusions: Our mortality rates are similar to international data. This type of audit reviews local outcomes and identifies factors contributing to mortality aiming to improve standards of care.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Neoplasias/mortalidad , Neoplasias/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Factores de Tiempo , Estudios Retrospectivos
20.
BMJ Open ; 9(5): e026391, 2019 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-31061036

RESUMEN

OBJECTIVE: To estimate the association between cumulative anticholinergic burden and falls and fractures in patients with overactive bladder (OAB). DESIGN: A retrospective claims-based study (2007-2015) of patients with OAB; outcomes from a subset were contrasted to a non-OAB comparison. SETTING: United States, commercially and Medicare-insured population. PARTICIPANTS: 154 432 adults with OAB and 86 966 adults without OAB, mean age of 56 years, and 67.9% women. MAIN OUTCOME MEASURES: Cumulative anticholinergic burden, a unitless value representing exposure over time, was estimated over the 12 months pre-index ('at baseline') and every 6 months post index. Burden was categorised as no burden (0), low burden (1-89), medium burden (90-499) or high burden (500+). Unadjusted rates of falls or fractures were estimated, and the increased risk associated with anticholinergic burden (measured at the closest 6-month interval prior to a fall or fracture) was assessed using a Cox proportional hazards model and a marginal structural model. RESULTS: Median (IQR) baseline anticholinergic burden was 30 (0.0-314.0) and higher among older (≥65 years, 183 [3.0-713.0]) versus younger (<65 years, 13 [0.0-200.0]) adults. The unadjusted rate of falls or fractures over the period was 5.0 per 100 patient-years, ranging from 3.1 (95% CI 3.0-3.2) for those with no burden, to 7.4 (95% CI 7.1-7.6) for those with high burden at baseline. The adjusted risk of falls and fractures was greater with higher anticholinergic burden in the previous 6 months, with an HR of 1.2 (95% CI 1.2 to 1.3) for low burden versus no burden, to 1.4 (95% CI 1.3 to 1.4) for high versus no burden. Estimates from marginal structural models adjusting for time-varying covariates were lower but remained significantly higher with a higher anticholinergic burden. Rates of falls and fractures were approximately 40% higher among those with OAB (vs those without). CONCLUSION: Higher levels of anticholinergic burden are associated with higher rates of falls and fractures, highlighting the importance of considering anticholinergic burden when treating patients with OAB.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Antagonistas Colinérgicos/administración & dosificación , Fracturas Óseas/epidemiología , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/epidemiología , Anciano , Anciano de 80 o más Años , Antagonistas Colinérgicos/efectos adversos , Femenino , Costos de la Atención en Salud , Humanos , Modelos Logísticos , Masculino , Medicare , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
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