Resumen
La enfermedad de Alzheimer (EA) es la forma más común de demencia y tiene una elevada morbilidad y mortalidad. La EA se caracteriza principalmente por la presencia de dos estructuras ...aberrantes en el cerebro de los pacientes, placas seniles formadas por péptido-β-amiloide (Aβ) y ovillos neurofibrilares cuyo principal componente es la proteína tau fosforilada. Aunque actualmente no se conoce bien la etiopatogenia, cada vez son más los estudios que demuestran un efecto causal del microbioma intestinal sobre la EA y las funciones cognitivas, a través del "eje microbiota intestino-cerebro". Las evidencias científicas sugieren un posible efecto protector de los polifenoles del vino frente a los trastornos neurodegenerativos aunque se desconocen los mecanismos y, hasta el momento, los estudios para evaluar de forma exhaustiva el efecto del vino sobre la etiopatogenia de la EA son muy escasos. El objetivo principal de la línea de investigación que enmarca este trabajo es entender cómo la dieta, y especialmente los polifenoles presentes en los alimentos vegetales, y otros factores del estilo de vida interactúan con el microbioma oral e intestinal, en relación con la salud digestiva y el deterioro cognitivo. Para ello, se está llevando a cabo una aproximación experimental que tiene como finalidad evaluar el posible efecto protector de los polifenoles del vino, mediante la suplementación de la dieta en dos modelos murinos de la EA (patología Aß y Tau), y, por otro lado, se está profundizando en el estudio de los mecanismos de protección mediante la evaluación de los efectos del ácido protocatéquico sobre la actividad eléctrica del cerebro.
Alzheimer's disease (AD) is the most common form of age-related dementia with high morbidity and mortality. AD is mainly characterized by the presence of two aberrant structures in the brain of patients, senile plaques formed by peptide-β-amyloid (Aβ) and neurofibrillary tangles whose main component is phosphorylated tau protein. Although the etiopathogenesis is currently not well understood, an increasing number of studies demonstrate a causal effect of the gut microbiome on AD and cognitive functions, through the "gut-brain microbiota axis". Scientific evidence suggests a possible protective effect of wine polyphenols against neurodegenerative disorders although the mechanisms are unknown and, so far, studies to evaluate comprehensively the effect of wine on the etiopathogenesis of AD are very scarce. The main objective of the research line that frames this work is to understand how diet, and especially the polyphenols present in plant foods, and other lifestyle factors interact with the oral and intestinal microbiome in relation to digestive health and cognitive impairment. To this end, an experimental approach is being carried out to evaluate the possible protective effect of wine polyphenols through dietary supplementation in two murine models of AD (Aß and Tau pathology), and, on the other hand, the study of the protective mechanisms is being deepened by evaluating the effects of protocatechuic acid on the electrical activity of the brain.
Context.
The abundance of
α
-elements provides an important fossil signature in Galactic archaeology to trace the chemical evolution of the different disc populations. High-precision chemical ...abundances are crucial to improving our understanding of the chemodynamical properties present in the Galaxy. However, deriving precise abundance estimations in the metal-rich disc (M/H > 0 dex) is still challenging.
Aims.
The aim of this paper is to analyse different error sources affecting magnesium abundance estimations from optical spectra of metal-rich stars.
Methods.
We derived Mg abundances for 87522 high-resolution spectra of 2210 solar neighbourhood stars from the AMBRE Project, and selected the 1172 best parametrised stars with more than four repeated spectra. For this purpose, the GAUGUIN automated abundance estimation procedure was employed.
Results.
The normalisation procedure has a strong impact on the derived abundances, with a clear dependence on the stellar type and the line intensity. For non-saturated lines, the optimal wavelength domain for the local continuum placement should be evaluated using a goodness-of-fit criterion, allowing mask-size dependence with the spectral type. Moreover, for strong saturated lines, applying a narrow normalisation window reduces the parameter-dependent biases of the abundance estimate, increasing the line-to-line abundance precision. In addition, working at large spectral resolutions always leads to better results than at lower ones. The resulting improvement in the abundance precision makes it possible to observe both a clear thin-thick disc chemical distinction and a decreasing trend in the magnesium abundance even at supersolar metallicities.
Conclusions.
In the era of precise kinematical and dynamical data, optimising the normalisation procedures implemented for large spectroscopic stellar surveys would provide a significant improvement to our understanding of the chemodynamical patterns of Galactic populations.
Context.
The abundance of
α
-elements relative to iron (
α
/Fe) is an important fossil signature in Galactic archaeology for tracing the chemical evolution of disc stellar populations. High-precision ...chemical abundances, together with accurate stellar ages, distances, and dynamical data, are crucial to infer the Milky Way formation history.
Aims.
The aim of this paper is to analyse the chemodynamical properties of the Galactic disc using precise magnesium abundance estimates for solar neighbourhood stars with accurate
Gaia
astrometric measurements.
Methods.
We estimated ages and dynamical properties for 366 main sequence turn-off stars from the AMBRE Project using PARSEC isochrones together with astrometric and photometric values from
Gaia
DR2. We use precise global metallicities M/H and Mg/Fe abundances from a previous study in order to estimate gradients and temporal chemodynamic relations for these stars.
Results.
We find a radial gradient of −0.099 ± 0.031 dex kpc
−1
for M/H and +0.023 ± 0.009 dex kpc
−1
for the Mg/Fe abundance. The steeper Mg/Fe gradient than that found in the literature is a result of the improvement of the AMBRE Mg/Fe estimates in the metal-rich regime. In addition, we find a significant spread of stellar age at any given Mg/Fe value, and observe a clear correlated dispersion of the Mg/Fe abundance with metallicity at a given age. While for M/H ≤ − 0.2, a clear age–Mg/Fe trend is observed, more metal-rich stars display ages from 3 up to 12 Gyr, describing an almost flat trend in the Mg/Fe–age relation. Moreover, we report the presence of radially migrated and/or churned stars for a wide range of stellar ages, although we note the large uncertainties of the amplitude of the inferred change in orbital guiding radii. Finally, we observe the appearance of a second chemical sequence in the outer disc, 10–12 Gyr ago, populating the metal-poor, low-Mg/Fe tail. These stars are more metal-poor than the coexisting stellar population in the inner parts of the disc, and show lower Mg/Fe abundances than prior disc stars of the same metallicity, leading to a chemical discontinuity. Our data favour the rapid formation of an early disc that settled in the inner regions, followed by the accretion of external metal-poor gas –probably related to a major accretion event such as the
Gaia
-Enceladus/Sausage one– that may have triggered the formation of the thin disc population and steepened the abundance gradient in the early disc.
Context.
Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of the Milky Way and external galaxies. However, its nucleosynthesis origin and abundance ...variations in the Galaxy are still unclear because the number of available stellar sulfur abundance measurements is currently rather small.
Aims.
The goal of the present article is to accurately and precisely study the sulfur content of large number of stars located in the solar neighbourhood.
Methods.
We use the parametrisation of thousands of high-resolution stellar spectra provided by the AMBRE Project, and combine it with the automated abundance determination GAUGUIN to derive local thermodynamic equilibrium sulfur abundances for 1855 slow-rotating FGK-type stars. This is the largest and most precise catalogue of sulfur abundances published to date. It covers a metallicity domain as high as ∼2.5 dex starting at M/H ∼ −2.0 dex.
Results.
We find that the sulfur-to-iron abundances ratio is compatible with a plateau-like distribution in the metal-poor regime, and then starts to decrease continuously at M/H ∼ −1.0 dex. This decrease continues towards negative values for supersolar metallicity stars as recently reported for magnesium and as predicted by Galactic chemical evolution models. Moreover, sulfur-rich stars having metallicities in the range − 1.0, −0.5 have very different kinematical and orbital properties with respect to more metal-rich and sulfur-poor ones. Two disc components, associated with the thin and thick discs, are thus seen independently in kinematics and sulfur abundances. The sulfur radial gradients in the Galactic discs have also been estimated. Finally, the enrichment in sulfur with respect to iron is nicely correlated with stellar ages: older metal-poor stars have higher S/M ratios than younger metal-rich ones.
Conclusions.
This work has confirmed that sulfur is an
α
-element that could be considered to explore the Galactic populations properties. For the first time, a chemo-dynamical study from the sulfur abundance point of view, as a stand-alone chemical element, is performed.
Mobile health (mHealth) is currently among the supporting elements that may contribute to an improvement in health markers by helping people adopt healthier lifestyles. mHealth interventions have ...been widely reported to achieve greater weight loss than other approaches, but their effect on body composition remains unclear.
This study aimed to assess the short-term (3 months) effectiveness of a mobile app and a smart band for losing weight and changing body composition in sedentary Spanish adults who are overweight or obese.
A randomized controlled, multicenter clinical trial was conducted involving the participation of 440 subjects from primary care centers, with 231 subjects in the intervention group (IG; counselling with smartphone app and smart band) and 209 in the control group (CG; counselling only). Both groups were counselled about healthy diet and physical activity. For the 3-month intervention period, the IG was trained to use a smartphone app that involved self-monitoring and tailored feedback, as well as a smart band that recorded daily physical activity (Mi Band 2, Xiaomi). Body composition was measured using the InBody 230 bioimpedance device (InBody Co., Ltd), and physical activity was measured using the International Physical Activity Questionnaire.
The mHealth intervention produced a greater loss of body weight (-1.97 kg, 95% CI -2.39 to -1.54) relative to standard counselling at 3 months (-1.13 kg, 95% CI -1.56 to -0.69). Comparing groups, the IG achieved a weight loss of 0.84 kg more than the CG at 3 months. The IG showed a decrease in body fat mass (BFM; -1.84 kg, 95% CI -2.48 to -1.20), percentage of body fat (PBF; -1.22%, 95% CI -1.82% to 0.62%), and BMI (-0.77 kg/m
, 95% CI -0.96 to 0.57). No significant changes were observed in any of these parameters in men; among women, there was a significant decrease in BMI in the IG compared with the CG. When subjects were grouped according to baseline BMI, the overweight group experienced a change in BFM of -1.18 kg (95% CI -2.30 to -0.06) and BMI of -0.47 kg/m
(95% CI -0.80 to -0.13), whereas the obese group only experienced a change in BMI of -0.53 kg/m
(95% CI -0.86 to -0.19). When the data were analyzed according to physical activity, the moderate-vigorous physical activity group showed significant changes in BFM of -1.03 kg (95% CI -1.74 to -0.33), PBF of -0.76% (95% CI -1.32% to -0.20%), and BMI of -0.5 kg/m
(95% CI -0.83 to -0.19).
The results from this multicenter, randomized controlled clinical trial study show that compared with standard counselling alone, adding a self-reported app and a smart band obtained beneficial results in terms of weight loss and a reduction in BFM and PBF in female subjects with a BMI less than 30 kg/m
and a moderate-vigorous physical activity level. Nevertheless, further studies are needed to ensure that this profile benefits more than others from this intervention and to investigate modifications of this intervention to achieve a global effect.
Clinicaltrials.gov NCT03175614; https://clinicaltrials.gov/ct2/show/NCT03175614.
RR2-10.1097/MD.0000000000009633.
This work is devoted to evaluating the relationship between the oxygen content and catalytic activity in the CO oxidation process of the 6H-type BaFeO3−δ system. Strong evidence is provided about the ...improvement of catalytic performance with increasing Fe average oxidation state, thus suggesting the involvement of lattice oxygen in the catalytic process. The compositional and structural changes taking place in both the anionic and cationic sublattices of the catalysts during redox cycles have been determined by temperature-resolved neutron diffraction. The obtained results evidence a structural transition from hexagonal (P63/mmc) to orthorhombic (Cmcm) symmetry. This transition is linked to octahedra distortion when the Fe3+ concentration exceeds 40% (δ values higher than 0.2). The topotactical character of the redox process is maintained in the δ range 0 < δ < 0.4. This suggests that the cationic framework is only subjected to slight structural modifications during the oxygen exchange process occurring during the catalytic cycle.
•RVC coated with Fe3O4 particles (21 ± 7 nm) as cathode for SO4− and H2O2 production.•Fe(II) active sites of Fe3O4 are electrocatalytic to reduce O2 and activate persulfate.•Adsorption and ...electrosorption enhance mass transport of Methylene Blue to the cathode.•After 18 min with 2 mM persulfate at Iapp = 10 mA: 100% color loss, > 80% TOC removal.•Reproducible color and TOC removals after 5 runs under the optimum conditions.
Peroxydisulfate (PDS, S2O82−)-based advanced oxidation processes have been developed as an alternative to those based on OH, as PDS activation yields a much more stable radical like SO4− that can maintain the oxidation ability of water treatment systems for longer time. Here, the electrochemical PDS activation has been investigated using reticulated vitreous carbon (RVC) substrate modified with Fe3O4 nanoparticles (NPs) as cathode. The NPs were exhaustively characterized by different surface analysis techniques (TEM, SEM) and Mössbauer spectroscopy. Cyclic voltammetry and linear sweep voltammetry with a rotating disk electrode allowed concluding that the main electrocatalytic role in the cathodic PDS activation to SO4− corresponded to the Fe(II) active sites continuously promoted upon cathodic polarization. These sites were less catalytic for O2 reduction reaction, although it was still feasible with n = 2.7 electrons as determined from Koutecky-Levich analysis. Both cathodic reactions followed an inner-sphere reaction mechanism. The Fe3O4-modified RVC cathodes were employed to electrolyze Methylene Blue aqueous solutions at pH 3.5, employing different current values and PDS concentrations. Dissolved O2 was purged to impede the competitive cathodic H2O2 production and Fenton’s reaction. The occurrence of dye adsorption/electrosorption on the cathode reduced the mass transport limitations, enhancing the reaction between SO4− and organic molecules. The best operation conditions to reach total and fast color removal at 18 min were 2 mM PDS and 10 mA, yielding > 80% TOC abatement at 45 min. Reproducible degradation profiles were found after 5 runs, thereby ensuring the stability of the Fe3O4-modified RVC, with no iron sludge production.
To estimate the incidence of early-onset dementia (EOD) and to compare the clinical characteristics of EOD vs late-onset dementia (LOD) in a geographically defined area.
We used data from the ...Registry of Dementia of Girona (ReDeGi), an epidemiologic surveillance system of dementia. The ReDeGi is a standardized clinical registry of new dementia cases diagnosed in the 7 hospitals of the Health Region of Girona (Catalonia, Spain), which encompasses an area of 5,517 km(2) and 690,207 inhabitants. EOD cases were defined as those patients residing in the target area at the time of diagnosis who were diagnosed with dementia with an age at onset of symptoms before 65 years.
The ReDeGi registered 2,083 patients between January 1, 2007, and December 31, 2009 (6.9% EOD). The incidence rate of EOD for the age range 30-64 was 13.4 cases per 100,000 person-years (95% confidence interval 11.3-15.8). Alzheimer disease was the most frequent cause of EOD (42.4%), followed by secondary dementia (18.1%), vascular dementia (13.8%), and frontotemporal dementia (9.7%). EOD cases at the time of diagnosis were less impaired on the Mini-Mental State Examination and had a greater score on the Blessed Dementia Rating Scale behavior subscale than LOD cases. The frequency of a personal history of depression was higher in EOD cases.
The incidence of EOD was less than 6 cases per 100,000 person-years in the age group 30-49 years; in the age group 50-64 years, the incidence rate was 3-fold higher and doubled with each 5-year increase.
Dental pulp is particularly interesting in regenerative medicine because of the accessibility and differentiation potential of the tissue. Dental pulp has an early developmental origin with ...multi-lineage differentiation potential as a result of its development during childhood and adolescence. However, no study has previously identified the presence of stem cell populations with embryonic-like phenotypes in human dental pulp from the third molar. In the present work, we describe a new population of dental pulp pluripotent-like stem cells (DPPSCs) that were isolated by culture in medium containing LIF, EGF and PDGF. These cells are SSEA4(+), OCT3/4(+), NANOG(+), SOX2(+), LIN28(+), CD13(+), CD105(+), CD34(-), CD45(-), CD90(+), CD29(+), CD73(+), STRO1(+) and CD146(-), and they show genetic stability in vitro based on genomic analysis with a newly described CGH technique. Interestingly, DPPSCs were able to form both embryoid-body-like structures (EBs) in vitro and teratoma-like structures that contained tissues derived from all three embryonic germ layers when injected in nude mice. We examined the capacity of DPPSCs to differentiate in vitro into tissues that have similar characteristics to mesoderm, endoderm and ectoderm layers in both 2D and 3D cultures. We performed a comparative RT-PCR analysis of GATA4, GATA6, MIXL1, NANOG, OCT3/4, SOX1 and SOX2 to determine the degree of similarity between DPPSCs, EBs and human induced pluripotent stem cells (hIPSCs). Our analysis revealed that DPPSCs, hIPSC and EBs have the same gene expression profile. Because DPPSCs can be derived from healthy human molars from patients of different sexes and ages, they represent an easily accessible source of stem cells, which opens a range of new possibilities for regenerative medicine.
Introduction
Withdrawal symptoms are common upon discontinuation of many psychotropic drugs. Catatonia, a neuropsychiatric condition characterized by a number of motor, behavioral, emotional, and ...autonomic abnormalities, has been described as a withdrawal syndrome in a growing number of case reports, but it is not well recognized. Treatment of catatonia usually includes benzodiazepines and electroconvulsive therapy. Standard consensus states that the use of neuroleptics should be avoided, as they are thought to worsen catatonia.
Objectives
With this case report, we attempt to contribute to the finding in literature that the withdrawal of clozapine may be associated with catatonia, and how reintroduction of clozapine could be indicated for its treatment.
Methods
A clinical case is presented of a 37-year-old female with a history of schizophrenia, presenting with altered mental status and new onset of catatonic signs and symptoms in the setting of a 7-day emetic syndrome. The possibility that vomiting prevented proper absorption of clozapine is postulated, causing the patient to present clinical features compatible with malignant catatonia.
Results
The patient required treatment with benzodiazepines, electroconvulsive therapy and clozapine re-initiation, leading to improvement of catatonic symptoms within a few days.
Conclusions
This case serves as a reminder to consider alternative diagnostic hypotheses in cases of catatonic syndrome unresponsive to standard treatments. When the clinical suspicion of drug withdrawal is high, restarting the discontinued medication, even an antipsychotic agent, may be indicated.
Disclosure
No significant relationships.
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