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71.
Abraham Martín Nuria Vázquez-Villoldo Vanessa Gómez-Vallejo Daniel Padro Federico N. Soria Boguslaw Szczupak Sandra Plaza-García Ander Arrieta Torsten Reese Jordi Llop Maria Domercq Carlos Matute 《European journal of nuclear medicine and molecular imaging》2016,43(6):1124-1138
Purpose
Glutamate excitotoxicity contributes to oligodendroglial and axonal damage in multiple sclerosis pathology. Extracellular glutamate concentration in the brain is controlled by cystine/glutamate antiporter (system xc-), a membrane antiporter that imports cystine and releases glutamate. Despite this, the system xc? activity and its connection to the inflammatory reaction in multiple sclerosis (MS) is largely unknown.Methods
Longitudinal in vivo magnetic resonance (MRI) and positron emission tomography (PET) imaging studies with 2-[18F]Fluoro-2-deoxy-D-glucose ([18F]FDG), [11C]-(R)-(1-(2-chlorophenyl)-N-methyl-N-1(1-methylpropyl)-3-isoquinolinecarboxamide ([11C]PK11195) and (4S)-4-(3-18F-fluoropropyl)-L-glutamate ([18F]FSPG) were carried out during the course of experimental autoimmune encephalomyelitis (EAE) induction in rats.Results
[18F]FSPG showed a significant increase of system xc? function in the lumbar section of the spinal cord at 14 days post immunization (dpi) that stands in agreement with the neurological symptoms and ventricle edema formation at this time point. Likewise, [18F]FDG did not show significant changes in glucose metabolism throughout central nervous system and [11C]PK11195 evidenced a significant increase of microglial/macrophage activation in spinal cord and cerebellum 2 weeks after EAE induction. Therefore, [18F]FSPG showed a major capacity to discriminate regions of the central nervous system affected by the MS in comparison to [18F]FDG and [11C]PK11195. Additionally, clodronate-treated rats showed a depletion in microglial population and [18F]FSPG PET signal in spinal cord confirming a link between neuroinflammatory reaction and cystine/glutamate antiporter activity in EAE rats.Conclusions
Altogether, these results suggest that in vivo PET imaging of system xc? could become a valuable tool for the diagnosis and treatment evaluation of MS.72.
José Luis Muñoz Tanya Gabaldón Elena Miranda Diana Lorena Berrio Jaime Ruiz-Tovar José María Ronda Nuria Esteve Antonio Arroyo Ana Pérez 《Obesity surgery》2016,26(11):2648-2653
Background
In bariatric surgery, there are no guidelines available for intraoperative fluid administration. Goal-directed fluid therapy (GDFT) is a new concept of perioperative fluid management that has been shown to improve the prognosis of patients undergoing abdominal surgery. The aim of our study is to assess the impact of the implementation of a GDFT protocol in morbidly obese patients who underwent laparoscopic sleeve gastrectomy (LSG).Methods
A before-after intervention study, in morbidly obese patients who underwent LSG, was conducted at the Obesity Unit of the General University Hospital Elche. Data from the GDFT implementation group (January 2014 to December 2015) were prospectively collected and compared with a preimplementation group (January 2012 to December 2013).Results
Baseline demographic and comorbidity data between the two groups of patients were similar. The length of stay in the hospital was significantly shortened in GDFT group from 4.5 to 3.44 days (p?<?0.001). Intraoperative fluid administration was significantly lower in the GDFT group (1002.4 vs 1687.2 ml in preimplementation group, p?<?0.001). In the postoperative period, there was a statistically significant reduction in postoperative nausea and vomiting (PONV) after GDFT implementation (48 to 14.3 %, p?<?0.001).Conclusions
Implementation of GDFT protocols can prevent intraoperative fluid overload in patients undergoing bariatric surgery. It could improve outcomes, for example decreasing PONV or even hospital stay.73.
74.
75.
Josep Antoni Ramos-Quiroga Margarida Corominas-Roso Gloria Palomar Nuria Gomez-Barros Marta Ribases Cristina Sanchez-Mora Rosa Bosch Mariana Nogueira Montserrat Corrales Sergi Valero Miguel Casas 《Psychopharmacology》2014,231(7):1389-1395
Rationale
Atomoxetine (ATX) is a non-stimulant drug approved for the treatment of attention deficit hyperactivity disorder (ADHD). Although animal models have provided evidence that brain-derived neurotrophic factor (BDNF) is involved in the effects of ATX in the brain, there are no studies of BDNF in ADHD patients undergoing treatment with ATX.Objectives
The aim of this study was to evaluate the possible changes in serum levels of BDNF in adults treated with ATX and its relationship with clinical improvement.Methods
A total of 54 adults with ADHD (age 33.43?±?8.99 years) without any medical or psychiatric comorbidities were treated with ATX for 3 months; 35 of them completed the protocol. The clinical data for ADHD diagnosis, including Conners’ ADHD Rating Scale and blood samples, were collected at baseline (V1) and at the end of the treatment (V2).Results
Adults with ADHD who completed ATX treatment for 3 months showed a significant improvement in their clinical symptoms. No significant differences were found in BDNF levels before and after treatment with ATX in the whole group of patients (p?=?0.15). The inattentive subgroup of ATX responders showed a decrease of serum BDNF after 3 months of ATX treatment (p?=?0.05) not present in the combined subtype (p?=?0.82).Conclusions
These results suggest that BDNF is not directly involved in the neurobiological mechanisms of ATX-induced improvement of clinical symptoms of ADHD. The differences between the combined and inattentive subtypes in serum BDNF changes suggest selective ATX-induced effects in the function of brain circuitry. 相似文献76.
The number of reinforced concrete structures subject to anoxic conditions such as offshore platforms and geological storage facilities is growing steadily. This study explored the behaviour of embedded steel reinforcement corrosion under anoxic conditions in the presence of different chloride concentrations. Corrosion rate values were obtained by three electrochemical techniques: Linear polarization resistance, electrochemical impedance spectroscopy, and chronopotenciometry. The corrosion rate ceiling observed was 0.98 µA/cm2, irrespective of the chloride content in the concrete. By means of an Evans diagram, it was possible to estimate the value of the cathodic Tafel constant (bc) to be 180 mV dec−1, and the current limit yielded an ilim value of 0.98 µA/cm2. On the other hand, the corrosion potential would lie most likely in the −900 mVAg/AgCl to −1000 mVAg/AgCl range, whilst the bounds for the most probable corrosion rate were 0.61 µA/cm2 to 0.22 µA/cm2. The experiments conducted revealed clear evidence of corrosion-induced pitting that will be assessed in subsequent research. 相似文献
77.
Michael Marks Pere Millat-Martinez Dan Ouchi Chrissy h Roberts Andrea Alemany Marc Corbacho-Monné Maria Ubals Aurelio Tobias Cristian Tebé Ester Ballana Quique Bassat Bàrbara Baro Martí Vall-Mayans Camila G-Beiras Nuria Prat Jordi Ara Bonaventura Clotet Oriol Mitjà 《The Lancet infectious diseases》2021,21(5):629-636
78.
79.
Jaume Francisco-Pascual Javier Cantalapiedra-Romero Jordi P rez-Rodon Bego a Benito Alba Santos-Ortega Jenson Maldonado Ignacio Ferreira-Gonzalez Nuria Rivas-G ndara 《World journal of cardiology》2021,13(11):608-627
Palpitations are one of the most common reasons for medical consultation. They tend to worry patients and can affect their quality of life. They are often a symptom associated with cardiac rhythm disorders, although there are other etiologies. For diagnosis, it is essential to be able to reliably correlate the sym ptoms with an electrocardiographic record allowing the identification or ruling out of a possible rhythm disorder. However, reaching a diagnosis is not always simple, given that they tend to be transitory symptoms and the patient is frequently asymptomatic at the time of assessment. In recent years, electrocardiographic monitoring systems have incorporated many technical improvements that solve several of the 24-h Holter monitor limitations. The objective of this review is to provide an update on the different monitoring methods currently available, remarking their indications and limitations, to help healthcare professionals to appropriately select and use them in the work-up of patients with palpitations. 相似文献
80.
Yu Z Sánchez-Velar N Catrina IE Kittler EL Udofia EB Zapp ML 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(11):4027-4032
An important goal of contemporary HIV type 1 (HIV-1) research is to identify cellular cofactors required for viral replication. The HIV-1 Rev protein facilitates the cytoplasmic accumulation of the intron-containing viral gag-pol and env mRNAs and is required for viral replication. We have previously shown that a cellular protein, human Rev-interacting protein (hRIP), is an essential Rev cofactor that promotes the release of incompletely spliced HIV-1 RNAs from the perinuclear region. Here, we use complementary genetic approaches to ablate hRIP activity and analyze HIV-1 replication and viral RNA localization. We find that ablation of hRIP activity by a dominant-negative mutant or RNA interference inhibits virus production by mislocalizing Rev-directed RNAs to the nuclear periphery. We further show that depletion of endogenous hRIP by RNA interference results in the loss of viral replication in human cell lines and primary macrophages; virus production was restored to wild-type levels after reintroduction of hRIP protein. Taken together, our results indicate that hRIP is an essential cellular cofactor for Rev function and HIV-1 replication. Because hRIP is not required for cell viability, it may be an attractive target for the development of new antiviral strategies. 相似文献