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The bioactive properties of olive (Olea europaea) fruits and olive oil are largely attributed to terpenoid compounds, including diverse triterpenoids such as oleanolic, maslinic and ursolic acids, erythrodiol, and uvaol. They have applications in the agri-food, cosmetics, and pharmaceutical industries. Some key steps involved in the biosynthesis of these compounds are still unknown. Genome mining, biochemical analysis, and trait association studies have been used to identify major gene candidates controlling triterpenoid content of olive fruits. Here, we identify and functionally characterize an oxidosqualene cyclase (OeBAS) required for the production of the major triterpene scaffold ß-amyrin, the precursor of erythrodiol, oleanolic and maslinic acids, and a cytochrome P450 (CYP716C67) that mediates 2α oxidation of the oleanane- and ursane-type triterpene scaffolds to produce maslinic and corosolic acids, respectively. To confirm the enzymatic functions of the entire pathway, we have reconstituted the olive biosynthetic pathway for oleanane- and ursane-type triterpenoids in the heterologous host, Nicotiana benthamiana. Finally, we have identified genetic markers associated with oleanolic and maslinic acid fruit content on the chromosomes carrying the OeBAS and CYP716C67 genes. Our results shed light on the biosynthesis of olive triterpenoids and provide new gene targets for germplasm screening and breeding for high triterpenoid content.
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Olea , Triterpenos , Olea/genética , Frutas/metabolismo , Fitomejoramiento , Triterpenos/metabolismoRESUMEN
This Special Issue is aimed to collect scientific papers that support holistic methodological approaches, both top-down and horizontal, for the correct application of various omics sciences because, when well-integrated, they can contribute to our understanding of the genotypic plasticity of plant species [...].
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Plantas , Plantas/genética , Plantas/metabolismoRESUMEN
Freezing of gait is a disabling symptom of Parkinson's disease that causes a paroxysmal inability to generate effective stepping. The underlying pathophysiology has recently migrated towards a dysfunctional supraspinal locomotor network, but the actual network derangements during ongoing gait freezing are unknown. We investigated the communication between the cortex and the subthalamic nucleus, two main nodes of the locomotor network, in seven freely-moving subjects with Parkinson's disease with a novel deep brain stimulation device, which allows on-demand recording of subthalamic neural activity from the chronically-implanted electrodes months after the surgical procedure. Multisite neurophysiological recordings during (effective) walking and ongoing gait freezing were combined with kinematic measurements and individual molecular brain imaging studies. Patients walked in a supervised environment closely resembling everyday life challenges. We found that during (effective) walking, the cortex and subthalamic nucleus were synchronized in a low frequency band (4-13 Hz). In contrast, gait freezing was characterized in every patient by low frequency cortical-subthalamic decoupling in the hemisphere with less striatal dopaminergic innervation. Of relevance, this decoupling was already evident at the transition from normal (effective) walking into gait freezing, was maintained during the freezing episode, and resolved with recovery of the effective walking pattern. This is the first evidence for a decoding of the networked processing of locomotion in Parkinson's disease and suggests that freezing of gait is a 'circuitopathy' related to a dysfunctional cortical-subcortical communication. A successful therapeutic approach for gait freezing in Parkinson's disease should aim at directly targeting derangements of neural network dynamics.
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Corteza Cerebral/fisiopatología , Trastornos Neurológicos de la Marcha/fisiopatología , Enfermedad de Parkinson/fisiopatología , Núcleo Subtalámico/fisiopatología , Electrodos Implantados , Femenino , Trastornos Neurológicos de la Marcha/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiopatología , Enfermedad de Parkinson/complicaciones , CaminataRESUMEN
Deep brain stimulation of the internal globus pallidus is a highly effective and established therapy for primary generalized and cervical dystonia, but therapeutic success is compromised by a non-responder rate of up to 25%, even in carefully-selected groups. Variability in electrode placement and inappropriate stimulation settings may account for a large proportion of this outcome variability. Here, we present probabilistic mapping data on a large cohort of patients collected from several European centres to resolve the optimal stimulation volume within the pallidal region. A total of 105 dystonia patients with pallidal deep brain stimulation were enrolled and 87 datasets (43 with cervical dystonia and 44 with generalized dystonia) were included into the subsequent 'normative brain' analysis. The average improvement of dystonia motor score was 50.5 ± 30.9% in cervical and 58.2 ± 48.8% in generalized dystonia, while 19.5% of patients did not respond to treatment (<25% benefit). We defined probabilistic maps of anti-dystonic effects by aggregating individual electrode locations and volumes of tissue activated (VTA) in normative atlas space and ranking voxel-wise for outcome distribution. We found a significant relation between motor outcome and the stimulation volume, but not the electrode location per se. The highest probability of stimulation induced motor benefit was found in a small volume covering the ventroposterior globus pallidus internus and adjacent subpallidal white matter. We then used the aggregated VTA-based outcome maps to rate patient individual VTAs and trained a linear regression model to predict individual outcomes. The prediction model showed robustness between the predicted and observed clinical improvement, with an r2 of 0.294 (P < 0.0001). The predictions deviated on average by 16.9 ± 11.6 % from observed dystonia improvements. For example, if a patient improved by 65%, the model would predict an improvement between 49% and 81%. Results were validated in an independent cohort of 10 dystonia patients, where prediction and observed benefit had a correlation of r2 = 0.52 (P = 0.02) and a mean prediction error of 10.3% (±8.9). These results emphasize the potential of probabilistic outcome brain mapping in refining the optimal therapeutic volume for pallidal neurostimulation and advancing computer-assisted planning and programming of deep brain stimulation.
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Mapeo Encefálico/métodos , Estimulación Encefálica Profunda/métodos , Distonía/diagnóstico por imagen , Distonía/terapia , Globo Pálido/diagnóstico por imagen , Globo Pálido/fisiología , Adulto , Anciano , Estimulación Encefálica Profunda/instrumentación , Distonía/fisiopatología , Electrodos Implantados , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Levodopa-induced dyskinesias are a common and disabling side effect of dopaminergic therapy in Parkinson's disease, but their neural mechanisms in vivo are still poorly understood. Besides striatal pathology, the importance of cortical dysfunction has been increasingly recognized. The supplementary motor area in particular, may have a relevant role in dyskinesias onset given its involvement in endogenously generated actions. The aim of the present study was to investigate the levodopa-related cortical excitability changes along with the emergence of levodopa-induced peak-of-dose dyskinesias in subjects with Parkinson's disease. Thirteen patients without dyskinesias and ten with dyskinesias received 200/50 mg fast-acting oral levodopa/benserazide following overnight withdrawal (12 hr) from their dopaminergic medication. We targeted transcranial magnetic stimulation to the supplementary motor area, ipsilateral to the most dopamine-depleted striatum defined with single-photon emission computed tomography with [123 I]N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)nortropane, and recorded transcranial magnetic stimulation-evoked potentials with high-density electroencephalography before and at 30, 60, and 180 min after levodopa/benserazide intake. Clinical improvement from levodopa/benserazide paralleled the increase in cortical excitability in both groups. Subjects with dyskinesias showed higher fluctuation of cortical excitability in comparison to non-dyskinetic patients, possibly reflecting dyskinetic movements. Together with endogenous brain oscillation, levodopa-related dynamics of brain state could influence the therapeutic response of neuromodulatory interventions.
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Antiparkinsonianos/uso terapéutico , Benserazida/farmacología , Levodopa/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Combinación de Medicamentos , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Corteza Motora/fisiopatología , Enfermedad de Parkinson/fisiopatología , Estimulación Magnética Transcraneal/métodosRESUMEN
Microfluidic devices reproducing 3D networks are particularly valuable for nanomedicine applications such as tissue engineering and active cell sorting. There is however a gap in the possibility to measure how the flow evolves in such 3D structures. We show here that it is possible to map 3D flows in complex microchannel networks by combining wide field illumination to image correlation approaches. For this purpose, we have derived the spatiotemporal image correlation analysis of time stacks of single-plane illumination microscopy images. From the detailed analytical and numerical analysis of the resulting model, we developed a fitting method that allows us to measure, besides the in-plane velocity, the out-of-plane velocity component down to vz â 65 µm/s. We have applied this method successfully to the 3D reconstruction of flows in microchannel networks with planar and 3D ramifications. These different network architectures have been realized by exploiting the great prototyping ability of a 3D printer, whose precision can reach few tens of micrometers, coupled to poly dimethyl-siloxane soft-printing lithography.
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The juxtaposition of fused cyclobutadienoid (CBD) with benzenoid creates intriguing alternating antiaromatic and aromatic conjugation. Synthetic accessibility of such molecules, however, has been challenging and limited in scope. We report a modular and streamlined synthetic strategy to access a large variety of polycyclic conjugated hydrocarbons with fused CBD. Synthesis was achieved through efficient palladium-catalyzed C-H activated annulation between abundant aryl bromides and oxanorbornenes, followed by aromatization under acidic conditions. The influence of four-membered ring was examined using spectroscopy, crystallography, and computation. This strategy will facilitate exploration on the chemical, structural, and electronic properties of such conjugated systems containing CBD.
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Background and Aims: Olive is considered a native plant of the eastern side of the Mediterranean basin, from where it should have spread westward along the Mediterranean shores, while little is known about its diffusion in the eastern direction. Methods: Genetic diversity levels and population genetic structure of a wide set of olive ecotypes and varieties collected from several provinces of Iran, representing a high percentage of the entire olive resources present in the area, was screened with 49 chloroplast and ten nuclear simple sequence repeat markers, and coupled with archaeo-botanical and historical data on Mediterranean olive varieties. Approximate Bayesian Computation was applied to define the demographic history of olives including Iranian germplasm, and species distribution modelling was performed to understand the impact of the Late Quaternary on olive distribution. Key Results: The results of the present study demonstrated that: (1) the climatic conditions of the last glacial maximum had an important role on the actual olive distribution, (2) all Iranian olive samples had the same maternal inheritance as Mediterranean cultivars, and (3) the nuclear gene flow from the Mediterranean basin to the Iranian plateau was almost absent, as well as the contribution of subspecies cuspidata to the diversity of Iranian olives. Conclusions: Based on this evidence, a new scenario for the origin and distribution of this important fruit crop has been traced. The evaluation of olive trees growing in the eastern part of the Levant highlighted a new perspective on the spread and distribution of olive, suggesting two routes of olive differentiation, one westward, spreading along the Mediterranean basin, and another moving towards the east and reaching the Iranian plateau before its domestication.
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Variación Genética , Olea/genética , Teorema de Bayes , ADN de Cloroplastos/genética , Flujo Génico , Patrón de Herencia , Irán , Repeticiones de MicrosatéliteRESUMEN
Thalamic deep brain stimulation is a mainstay treatment for severe and drug-refractory essential tremor, but postoperative management may be complicated in some patients by a progressive cerebellar syndrome including gait ataxia, dysmetria, worsening of intention tremor and dysarthria. Typically, this syndrome manifests several months after an initially effective therapy and necessitates frequent adjustments in stimulation parameters. There is an ongoing debate as to whether progressive ataxia reflects a delayed therapeutic failure due to disease progression or an adverse effect related to repeated increases of stimulation intensity. In this study we used a multimodal approach comparing clinical stimulation responses, modelling of volume of tissue activated and metabolic brain maps in essential tremor patients with and without progressive ataxia to disentangle a disease-related from a stimulation-induced aetiology. Ten subjects with stable and effective bilateral thalamic stimulation were stratified according to the presence (five subjects) of severe chronic-progressive gait ataxia. We quantified stimulated brain areas and identified the stimulation-induced brain metabolic changes by multiple 18 F-fluorodeoxyglucose positron emission tomography performed with and without active neurostimulation. Three days after deactivating thalamic stimulation and following an initial rebound of symptom severity, gait ataxia had dramatically improved in all affected patients, while tremor had worsened to the presurgical severity, thus indicating a stimulation rather than disease-related phenomenon. Models of the volume of tissue activated revealed a more ventrocaudal stimulation in the (sub)thalamic area of patients with progressive gait ataxia. Metabolic maps of both patient groups differed by an increased glucose uptake in the cerebellar nodule of patients with gait ataxia. Our data suggest that chronic progressive gait ataxia in essential tremor is a reversible cerebellar syndrome caused by a maladaptive response to neurostimulation of the (sub)thalamic area. The metabolic signature of progressive gait ataxia is an activation of the cerebellar nodule, which may be caused by inadvertent current spread and antidromic stimulation of a cerebellar outflow pathway originating in the vermis. An anatomical candidate could be the ascending limb of the uncinate tract in the subthalamic area. Adjustments in programming and precise placement of the electrode may prevent this adverse effect and help fine-tuning deep brain stimulation to ameliorate tremor without negative cerebellar signs.
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Estimulación Encefálica Profunda/efectos adversos , Ataxia de la Marcha/etiología , Tálamo/fisiología , Anciano , Anciano de 80 o más Años , Biofisica , Temblor Esencial/diagnóstico por imagen , Temblor Esencial/terapia , Femenino , Fluorodesoxiglucosa F18/metabolismo , Ataxia de la Marcha/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos XRESUMEN
In vivo studies of blood circulation pathologies have great medical relevance and need methods for the characterization of time varying flows at high spatial and time resolution in small animal models. We test here the efficacy of the combination of image correlation techniques and single plane illumination microscopy (SPIM) in characterizing time varying flows in vitro and in vivo. As indicated by numerical simulations and by in vitro experiments on straight capillaries, the complex analytical form of the cross-correlation function for SPIM detection can be simplified, in conditions of interest for hemodynamics, to a superposition of Gaussian components, easily amenable to the analysis of variable flows. The possibility to select a wide field of view with a good spatial resolution along the collection optical axis and to compute the cross-correlation between regions of interest at varying distances on a single time stack of images allows one to single out periodic flow components from spurious peaks on the cross-correlation functions and to infer the duration of each flow component. We apply this cross-correlation analysis to the blood flow in Zebrafish embryos at 4 days after fertilization, measuring the average speed and the duration of the systolic and diastolic phases.
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Hemodinámica , Pez Cebra/fisiología , Animales , Fluorescencia , Colorantes Fluorescentes/química , Microscopía Fluorescente/métodos , Microesferas , Pulso Arterial , Rodaminas/química , Tiempo , Liposomas Unilamelares/químicaAsunto(s)
Estimulación Encefálica Profunda , Temblor Esencial , Cerebelo , Ataxia de la Marcha , Humanos , TemblorRESUMEN
Background: People with Severe Mental Illness (SMI) (schizophrenia, bipolar disorder, major depressive disorder, and personality disorders) experience a considerable risk of premature mortality because of cardiovascular disease, smoking, metabolic syndrome, etc. Recent research has demonstrated that this population spends almost 13 h per day being sedentary. Sedentary behavior (SB) is an independent risk factor for cardiovascular disease and mortality. Given the potential for physical activity (PA) to improve health and well-being in people with SMI, we developed a pilot randomized controlled trial (RCT) to evaluate a group intervention aimed at reducing SB and increasing PA of inpatients with SMI. Our primary aim is to assess the acceptability and feasibility of Men.Phys protocol, a new integrated treatment protocol for psychiatric inpatients. Secondary aims are to verify if the Men.Phys protocol decreased sedentary behavior and increased well-being, in terms of quality sleep, quality of life, and psychopathological symptoms and other measures. Methods: Will be enrolled people with SMI consecutively admitted to the emergency psychiatric ward in Colleferro, near Rome. Participant's physical activity, health, psychiatric and psychological status will be assessed at baseline. Randomised participants will receive treatment as usual (TAU) or the Men.Phys intervention. Men.Phys involves a group activity conducted by a mental health practitioner, during which patients repeat exercises that showed through a monitor. The protocol provides that, during hospitalization, the patient follow at least 3 sessions consecutively. Lazio 1 ethics Committee approved this research protocol. Results and Conclusions: To our knowledge, Men.Phys is the first RCT to investigate the impact of a group intervention targeting sedentary behavior in people with SMI during psychiatric hospitalization. If the intervention should be feasible and acceptable, further large-scale study can be developed and then implemented in routine care.
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Enfermedades Cardiovasculares , Trastornos Mentales , Humanos , Masculino , Ejercicio Físico , Trastornos Mentales/complicaciones , Trastornos Mentales/terapia , Trastornos Mentales/diagnóstico , Salud Mental , Ensayos Clínicos Controlados Aleatorios como Asunto , Conducta SedentariaRESUMEN
A brain-machine interface represents a promising therapeutic avenue for the treatment of many neurologic conditions. Deep brain stimulation (DBS) is an invasive, neuro-modulatory tool that can improve different neurologic disorders by delivering electric stimulation to selected brain areas. DBS is particularly successful in advanced Parkinson's disease (PD), where it allows sustained improvement of motor symptoms. However, this approach is still poorly standardized, with variable clinical outcomes. To achieve an optimal therapeutic effect, novel adaptive DBS (aDBS) systems are being developed. These devices operate by adapting stimulation parameters in response to an input signal that can represent symptoms, motor activity, or other behavioral features. Emerging evidence suggests greater efficacy with fewer adverse effects during aDBS compared with conventional DBS. We address this topic by discussing the basics principles of aDBS, reviewing current evidence, and tackling the many challenges posed by aDBS for PD.
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Interfaces Cerebro-Computador , Estimulación Encefálica Profunda , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/terapiaRESUMEN
Deep brain stimulation (DBS) of the subthalamic nucleus or the globus pallidus is an established treatment for Parkinson's disease (PD) that yields a marked and lasting improvement of motor symptoms. Yet, DBS benefit on gait disturbances in PD is still debated and can be a source of dissatisfaction and poor quality of life. Gait disturbances in PD encompass a variety of clinical manifestations and rely on different pathophysiological bases. While gait disturbances arising years after DBS surgery can be related to disease progression, early impairment of gait may be secondary to treatable causes and benefits from DBS reprogramming. In this review, we tackle the issue of gait disturbances in PD patients with DBS by discussing their neurophysiological basis, providing a detailed clinical characterization, and proposing a pragmatic programming approach to support their management.
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The extent and conditions of storage may affect the stability and quality of extra virgin olive oil (EVOO). This study aimed at evaluating the effects of different storage conditions (ambient, 4 °C and -18 °C temperatures, and argon headspace) on three EVOOs (low, medium, and high phenols) over 18 and 36 months, analyzing the main metabolites at six time points. The results showed that low temperatures are able to maintain all three EVOOs within the legal limits established by the current EU regulations for most compounds up to 36 months. Oleocanthal, squalene, and total phenols were affected by storage temperatures more than other compounds and degradation of squalene and α-tocopherol was inhibited only by low temperatures. The best temperature for 3-year conservation was 4 °C, but -18 °C represented the optimum temperature to preserve the organoleptic properties. The present study provided new insights that should guide EVOO manufacturers and traders to apply the most efficient storage methods to maintain the characteristics of the freshly extracted oils for a long conservation time.
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Deep brain stimulation (DBS) of the thalamic ventral intermediate nucleus is one of the main advanced neurosurgical treatments for drug-resistant tremor. However, not every patient may be eligible for this procedure. Nowadays, various other functional neurosurgical procedures are available. In particular cases, radiofrequency thalamotomy, focused ultrasound and radiosurgery are proven alternatives to DBS. Besides, other DBS targets, such as the posterior subthalamic area (PSA) or the dentato-rubro-thalamic tract (DRT), may be appraised as well. In this review, the clinical characteristics and pathophysiology of tremor syndromes, as well as long-term outcomes of DBS in different targets, will be summarized. The effectiveness and safety of lesioning procedures will be discussed, and an evidence-based clinical treatment approach for patients with drug-resistant tremor will be presented. Lastly, the future directions in the treatment of severe tremor syndromes will be elaborated.
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BACKGROUND: The cultivated olive (Olea europaea L.) is the most agriculturally important species of the Oleaceae family. Although many studies have been performed on plastid polymorphisms to evaluate taxonomy, phylogeny and phylogeography of Olea subspecies, only few polymorphic regions discriminating among the agronomically and economically important olive cultivars have been identified. The objective of this study was to sequence the entire plastome of olive and analyze many potential polymorphic regions to develop new inter-cultivar genetic markers. RESULTS: The complete plastid genome of the olive cultivar Frantoio was determined by direct sequence analysis using universal and novel PCR primers designed to amplify all overlapping regions. The chloroplast genome of the olive has an organisation and gene order that is conserved among numerous Angiosperm species and do not contain any of the inversions, gene duplications, insertions, inverted repeat expansions and gene/intron losses that have been found in the chloroplast genomes of the genera Jasminum and Menodora, from the same family as Olea.The annotated sequence was used to evaluate the content of coding genes, the extent, and distribution of repeated and long dispersed sequences and the nucleotide composition pattern. These analyses provided essential information for structural, functional and comparative genomic studies in olive plastids. Furthermore, the alignment of the olive plastome sequence to those of other varieties and species identified 30 new organellar polymorphisms within the cultivated olive. CONCLUSIONS: In addition to identifying mutations that may play a functional role in modifying the metabolism and adaptation of olive cultivars, the new chloroplast markers represent a valuable tool to assess the level of olive intercultivar plastome variation for use in population genetic analysis, phylogenesis, cultivar characterisation and DNA food tracking.
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Genoma del Cloroplasto , Olea/clasificación , Olea/genética , Filogenia , Polimorfismo Genético , ADN de Cloroplastos , ADN de Plantas/genética , Orden Génico , Genoma de Planta , Repeticiones de Microsatélite , Análisis de Secuencia de ADNRESUMEN
OBJECTIVES: The association between maternal celiac disease (CD) and both reduced fertility and increased risk of adverse pregnancy-related events has been long documented. However, no evidences are available regarding the pathogenic mechanisms of this link. The aim of this study was to determine whether anti-tissue transglutaminase (anti-tTG) antibodies are involved in the damage of trophoblastic cells in vitro. METHODS: Human primary trophoblastic cells, isolated from term placenta, were exposed to anti-tTG immunoglobulin G (IgG) antibodies, both commercially available and separated from sera of three untreated celiac women. The ability of anti-tTG antibodies to bind to trophoblastic cells, invasiveness of placental cells through a layer of extracellular matrix, and the activity of cellular matrix metalloprotease (MMP) and cellular apoptosis were evaluated, as indicators of trophoblast damage, by TdT-mediated dUTP digoxigenin nick end labeling (TUNEL) and annexin V expression. RESULTS: Anti-tTG IgG showed a specific dose- and time-dependent binding to human trophoblast. In addition, trophoblastic cells, after being exposed to anti-tTG IgG antibodies, both commercially available and separated from sera of celiac women, showed an impaired invasiveness, a decreased activity of cellular MMP, and a greater percentage of TUNEL positivity and annexin V positivity. CONCLUSIONS: We showed that the binding of anti-tTG antibodies to trophoblast might represent a key mechanism by which the embryo implantation and pregnancy outcome are impaired in untreated celiac pregnant women. Because healthy trophoblast development is essential for placental and fetal development, these data provide a novel mechanism for CD-induced infertility, early pregnancy loss, and intrauterine growth retardation.
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Apoptosis/inmunología , Enfermedad Celíaca/inmunología , Transglutaminasas/inmunología , Trofoblastos/inmunología , Anticuerpos Antiidiotipos , Enfermedad Celíaca/patología , Células Cultivadas , Femenino , Citometría de Flujo , Proteínas de Unión al GTP , Humanos , Etiquetado Corte-Fin in Situ , Placenta/inmunología , Placenta/patología , Embarazo , Proteína Glutamina Gamma Glutamiltransferasa 2 , Trofoblastos/patologíaRESUMEN
OBJECTIVE: This study explored whether Mastery, a domain of metacognition that reflects the ability to use knowledge about mental states to respond to psychological challenges, mediated the effects of neurocognition on the frequency of social contact and persons' capacity for social relatedness. METHOD: Participants were 102 adults with schizophrenia or schizoaffective disorder. Neurocognition was represented by a single factor score produced by a principal components analysis of a neurocognitive test battery. Mastery was assessed using the metacognitive assessment scale and social functioning by the quality of life scale. RESULTS: Using structural equation modeling, specifically measured-variable path analysis, a mediational model consisting of neurocognitive capacity linked to mastery and capacity for social relationships and mastery linked with frequency of social contact and capacity for social relatedness showed acceptable fit to the observed data. This persisted after controlling for negative and cognitive symptoms. CONCLUSION: Results suggest that certain forms of metacognition mediate the influence of neurocognition upon function in schizophrenia.