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21.
Ana B. Fagundo Susana Jiménez-Murcia Cristina Giner-Bartolomé Mohammed Anisul Islam Rafael de la Torre Antoni Pastor Felipe F. Casanueva Ana B. Crujeiras Roser Granero Rosa Ba?os Cristina Botella Jose M. Fernández-Real Gema Frühbeck Javier Gómez-Ambrosi José M. Menchón Francisco J. Tinahones Fernando Fernández-Aranda 《PloS one》2015,10(6)
The prefrontal (PFC) and orbitofrontal cortex (OFC) appear to be associated with both executive functions and olfaction. However, there is little data relating olfactory processing and executive functions in humans. The present study aimed at exploring the role of olfaction on executive functioning, making a distinction between primary and more cognitive aspects of olfaction. Three executive tasks of similar difficulty were used. One was used to assess hot executive functions (Iowa Gambling Task-IGT), and two as a measure of cold executive functioning (Stroop Colour and Word Test-SCWT and Wisconsin Card Sorting Test-WCST). Sixty two healthy participants were included: 31 with normosmia and 31 with hyposmia. Olfactory abilities were assessed using the ‘‘Sniffin’ Sticks’’ test and the olfactory threshold, odour discrimination and odour identification measures were obtained. All participants were female, aged between 18 and 60. Results showed that participants with hyposmia displayed worse performance in decision making (IGT; Cohen’s-d = 0.91) and cognitive flexibility (WCST; Cohen’s-d between 0.54 and 0.68) compared to those with normosmia. Multiple regression adjusted by the covariates participants’ age and education level showed a positive association between odour identification and the cognitive inhibition response (SCWT-interference; Beta = 0.29; p = .034). The odour discrimination capacity was not a predictor of the cognitive executive performance. Our results suggest that both hot and cold executive functions seem to be associated with higher-order olfactory functioning in humans. These results robustly support the hypothesis that olfaction and executive measures have a common neural substrate in PFC and OFC, and suggest that olfaction might be a reliable cognitive marker in psychiatric and neurologic disorders. 相似文献
22.
Zaida Agüera Xandra Romero Jon Arcelus Isabel Sánchez Nadine Riesco Susana Jiménez-Murcia Jana González-Gómez Roser Granero Nuria Custal Monica Montserrat-Gil de Bernabé Salomé Tárrega Rosa M. Ba?os Cristina Botella Rafael de la Torre José C. Fernández-García José M. Fernández-Real Gema Frühbeck Javier Gómez-Ambrosi Francisco J. Tinahones Ana B. Crujeiras Felipe F. Casanueva José M. Menchón Fernando Fernández-Aranda 《PloS one》2015,10(11)
The restoration of body composition (BC) parameters is considered to be one of the most important goals in the treatment of patients with anorexia nervosa (AN). However, little is known about differences between AN diagnostic subtypes [restricting (AN-R) and binge/purging (AN-BP)] and weekly changes in BC during refeeding treatment. Therefore, the main objectives of our study were twofold: 1) to assess the changes in BC throughout nutritional treatment in an AN sample and 2) to analyze predictors of BC changes during treatment, as well as predictors of treatment outcome. The whole sample comprised 261 participants [118 adult females with AN (70 AN-R vs. 48 AN-BP), and 143 healthy controls]. BC was measured weekly during 15 weeks of day-hospital treatment using bioelectrical impedance analysis (BIA). Assessment measures also included the Eating Disorders Inventory-2, as well as a number of other clinical indices. Overall, the results showed that AN-R and AN-BP patients statistically differed in all BC measures at admission. However, no significant time×group interaction was found for almost all BC parameters. Significant time×group interactions were only found for basal metabolic rate (p = .041) and body mass index (BMI) (p = .035). Multiple regression models showed that the best predictors of pre-post changes in BC parameters (namely fat-free mass, muscular mass, total body water and BMI) were the baseline values of BC parameters. Stepwise predictive logistic regressions showed that only BMI and age were significantly associated with outcome, but not with the percentage of body fat. In conclusion, these data suggest that although AN patients tended to restore all BC parameters during nutritional treatment, only AN-BP patients obtained the same fat mass values as healthy controls. Put succinctly, the best predictors of changes in BC were baseline BC values, which did not, however, seem to influence treatment outcome. 相似文献
23.
Leire Aguinagalde Bruno Corsini Arnau Domenech Mirian Domenech Jordi Cámara Carmen Ardanuy Ernesto García Josefina Li?ares Asunción Fenoll Jose Yuste 《PloS one》2015,10(9)
Capsular switching allows pre-existing clones of Streptococcus pneumoniae expressing vaccine serotypes to escape the vaccine-induced immunity by acquisition of capsular genes from pneumococci of a non-vaccine serotype. Here, we have analysed the clonal composition of 492 clinical isolates of serotype 11A causing invasive disease in Spain (2000–2012), and their ability to evade the host immune response. Antibiograms, serotyping and molecular typing were performed. The restriction profiles of pbp2x, pbp1a and pbp2b genes were also analysed. Interaction with the complement components C1q, C3b, C4BP, and factor H was explored whereas opsonophagocytosis assays were performed using a human cell line differentiated to neutrophils. Biofilm formation and the polymorphisms of the major autolysin LytA were evaluated. The main genotypes of the 11A pneumococci were: ST62 (447 isolates, 90.6%), followed by ST6521 (35 isolates, 7.3%) and ST838 (10 isolates, 2.1%). Beta lactam resistant serotype 11A variants of genotypes ST838 and ST6521 closely related to the Spain9V-ST156 clone were first detected in 2005. A different pattern of evasion of complement immunity and phagocytosis was observed between genotypes. The emergence of one vaccine escape variant of Spain9V-ST156 (ST652111A), showing a high potential to avoid the host immune response, was observed. In addition, isolates of ST652111A showed higher ability to produce biofilms than ST83811A or ST6211A, which may have contributed to the emergence of this PEN-resistant ST652111A genotype in the last few years. The emergence of penicillin-resistant 11A invasive variants of the highly successful ST156 clonal complex merits close monitoring. 相似文献
24.
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25.
Liffourrena AS Massimelli MJ Forrellad MA Lisa AT Domenech CE Lucchesi GI 《Current microbiology》2007,55(6):530-536
Pseudomonas aeruginosa expresses hemolytic phospholipase C (PlcH) with choline or under phosphate-limiting conditions. PlcH from these conditions
were differently eluted from the Celite-545 column after application of an ammonium sulfate linear reverse gradient. The PlcH
from supernatants of bacteria grown in the presence of choline was eluted with 30% ammonium sulfate and was more than 85%
inhibited by tetradecyltrimethylammonium. PlcH from supernatants of bacteria grown with succinate and ammonium ions in a low-phosphate
medium was eluted as a peak with 10% of salt and was less than 10% inhibited by tetradecyltrimethylammonium. PlcH from low
phosphate was purified associated with a protein of 17 kDa. This complex was dissociated and separated on a Sephacryl S-200
column with 1% (w/v) sodium dodecyl sulfate. After this dissociation, the resulting protein of 70 kDa, corresponding to PlcH,
was inhibited by tetradecyltrimethylammonium, showing a protection effect of the accompanying protein. RT-PCR analyses showed
that in choline media, the plcH gene was expressed independently of plcR. In low-phosphate medium, the plcH gene was expressed as a plcHR operon. Because plcR encodes for chaperone proteins, this result correlates with the observation that PlcH from supernatants of bacteria grown
in the presence of choline was purified without an accompanying protein. The consequence of the absence of this chaperone
was that tetradecyltrimethylammonium inhibited the PlcH activity. 相似文献
26.
Rodríguez-Muñoz M de la Torre-Madrid E Gaitán G Sánchez-Blázquez P Garzón J 《Cellular signalling》2007,19(12):2558-2571
Opioid agonists display different capacities to stimulate mu-opioid receptor (MOR) endocytosis, which is related to their ability to provoke the phosphorylation of specific cytosolic residues in the MORs. Generally, opioids that efficiently promote MOR endocytosis and recycling produce little tolerance, as is the case for [d-Ala2, N-MePhe4,Gly-ol5] encephalin (DAMGO). However, morphine produces rapid and profound antinociceptive desensitization in the adult mouse brain associated with little MOR internalization. The regulator of G-protein signaling, the RGS14 protein, associates with MORs in periaqueductal gray matter (PAG) neurons, and when RGS14 is silenced morphine increased the serine 375 phosphorylation in the C terminus of the MOR, a GRK substrate. Subsequently, these receptors were internalized and recycled back to the membrane where they accumulated on cessation of antinociception. These mice now exhibited a resensitized response to morphine and little tolerance developed. Thus, in morphine-activated MORs the RGS14 prevents GRKs from phosphorylating those residues required for β-arresting-mediated endocytosis. Moreover morphine but not DAMGO triggered a process involving calcium/calmodulin-dependent kinase II (CaMKII) in naïve mice, which contributes to MOR desensitization in the plasma membrane. In RGS14 knockdown mice morphine failed to activate this kinase. It therefore appears that phosphorylation and internalization of MORs disrupts the CaMKII-mediated negative regulation of these opioid receptors. 相似文献
27.
Aaron A. King Matthieu Domenech de Cellès Felicia M. G. Magpantay Pejman Rohani 《Proceedings. Biological sciences / The Royal Society》2015,282(1806)
As an emergent infectious disease outbreak unfolds, public health response is
reliant on information on key epidemiological quantities, such as transmission
potential and serial interval. Increasingly, transmission models fit to
incidence data are used to estimate these parameters and guide policy. Some
widely used modelling practices lead to potentially large errors in parameter
estimates and, consequently, errors in model-based forecasts. Even more
worryingly, in such situations, confidence in parameter estimates and forecasts
can itself be far overestimated, leading to the potential for large errors that
mask their own presence. Fortunately, straightforward and computationally
inexpensive alternatives exist that avoid these problems. Here, we first use a
simulation study to demonstrate potential pitfalls of the standard practice of
fitting deterministic models to cumulative incidence data. Next, we demonstrate
an alternative based on stochastic models fit to raw data from an early phase of
2014 West Africa Ebola virus disease outbreak. We show not only that bias is
thereby reduced, but that uncertainty in estimates and forecasts is better
quantified and that, critically, lack of model fit is more readily diagnosed. We
conclude with a short list of principles to guide the modelling response to
future infectious disease outbreaks. 相似文献
28.
Catalán V Gómez-Ambrosi J Rodríguez A Ramírez B Silva C Rotellar F Hernández-Lizoain JL Baixauli J Valentí V Pardo F Salvador J Frühbeck G 《The Journal of nutritional biochemistry》2011,22(7):634-641
Background
Obesity is widely recognised as an important risk factor for colorectal cancer (CC).Aim
The study aimed to evaluate the effect of CC on circulating concentrations and gene expression levels of inflammatory and angiogenesis-related factors in human visceral adipose tissue (VAT).Methods
VAT biopsies were obtained from 18 healthy individuals and 11 patients with CC. Real-time polymerase chain reactions were performed to quantify gene expression levels and zymographic analyses were used to determine the activity of matrix metalloproteinases (MMPs).Results
Patients with CC exhibited increased mRNA expression levels of lipocalin-2 (P=.014), osteopontin (P=.027), tumor necrosis factor-α (TNF-α) (P=.016) and chitinase-3 like-1 (P=.006) compared to control subjects in VAT. Gene expression levels of hypoxia-inducible factor-1 α, vascular endothelial growth factor and MMP-2 were significantly higher (P<.05) in VAT of patients with CC. The expression of insulin-like growth factor I, insulin growth factor binding protein 3 and MMP-9 followed the same trend, although no significant differences were reached. The enzymatic activity of MMP-9 was increased (P<.001) in patients with CC. Furthermore, individuals with CC showed increased (P<.05) circulating concentrations of the inflammatory markers interleukin-6, tumour necrosis factor α and hepatocyte growth factor, whereas levels of the anti-inflammatory adipokine adiponectin were decreased (P<.01).Conclusion
These findings represent the first observation that mRNA levels of the novel inflammatory factors lipocalin-2, chitinase-3 like-1 and osteopontin are increased in human VAT of subjects with CC. This observation together with the up-regulation of angiogenic factors suggests that adipokines secreted by VAT may be involved in the development of colon cancer. 相似文献29.
Following encoding, memory remains temporarily vulnerable to disruption. Consolidation refers to offline time-dependent processes that continue after encoding and stabilize, transform or enhance the memory trace. Memory consolidation resulting from sleep has been reported for declarative and non-declarative memories in humans. We first investigated the temporal course of memory retrieval in chimpanzees, bonobos and orangutans. We found that the amount of retrieved information was time dependent: apes' performance degraded after 1 and 2 h, stabilized after 4 h, started to increase after 8 and 12 h and fully recovered after 24 h. Second, we show that although memories during wakefulness were highly vulnerable to interference from events similar to those witnessed during the original encoding event, an intervening period of sleep not only stabilized apes' memories into more permanent ones but also protected them against interference. 相似文献