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1.
Int J Paediatr Dent ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894605

RESUMEN

BACKGROUND: Facial cellulitis of odontogenic origin (FCOO) can lead to systemic complications in children. Research on factors leading to improvement of outcomes is limited. AIM: The aim of this study was to investigate patient characteristics, treatment modalities (antibiotics and route of administration), length of stay in the hospital, time till definitive treatment and factors related to early treatment of FCOO. DESIGN: A retrospective review was performed to identify children presenting to the emergency department of a pediatric hospital with FCOO over a 5-year period. Data was extracted from records of included patients. RESULTS: Sixty-four records were included for analysis with mean age of 8.19 ± 4.5 years. Significantly more patients received clindamycin (79.7%) than penicillin-based antibiotic (18.8%) with P<0.0001. Forty-four (68.8%) children were admitted to the hospital and received parenteral clindamycin. The average hospital stay was 2.5 ± 1.2 days and average days till dental treatment was 5.2 ± 8.9 days. Children who received intravenous antibiotic or had a primary tooth involved received dental treatment sooner, with P=0.0036 and P=0.03 respectively. CONCLUSIONS: Oral antibiotics were prescribed for children who were discharged from the emergency department. Children who received intravenous antibiotics or had an infected primary tooth received early definitive treatment.

2.
Acad Emerg Med ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894606

RESUMEN

BACKGROUND: Risk of respiratory depression is increased when opioids are added to sedative agents. In our recent multi-center emergency department (ED) procedural sedation cohort we reported a strong association between pre-procedural opioids and sedation-related adverse events. We sought to examine the association between timing of opioids and the incidence of adverse sedation outcomes. METHODS: We conducted a secondary analysis of a prospective cohort of children aged 0-18 years who received sedation for a painful procedure in six Canadian pediatric EDs from July/2010-Feb/2015. Primary Risk Factor: timing of opioid administration; adjusted for age, opioid type, pre-procedural and sedation medications, and procedure type. OUTCOMES: a) oxygen desaturation, b) vomiting and c) positive pressure ventilation (PPV). RESULTS: Of the 6,295 children in the original cohort, 1,806 (29%) received a pre-procedural opioid. Patients receiving pre-procedural opioids had a higher incidence of oxygen desaturation (risk difference 4.3%, 95%CI 2.9 to 5.8%), vomiting (risk difference 2.0%, 95%CI 0.7 to 3.3%) and PPV (risk difference 1.5%, 95%CI 0.7 to 2.3%). Multivariable regression with timing of opioids modeled as a restricted cubic spline revealed the risk for each outcome was highest when opioids were administered in the 30 minutes prior to sedation. Timing of opioid administration was statistically significantly associated with oxygen desaturation and vomiting (p<0.0001) but not with PPV (p=0.113). CONCLUSION: Timing of opioids was significantly associated with the risk of oxygen desaturation and vomiting. Being aware of this increased risk will help clinicians prepare for sedation and the potential need for patient rescue.

3.
Environ Microbiol ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894607

RESUMEN

Adaptation to low-oxygen environment in host tissues is crucial for microbial pathogens, particuarlly fungi, to successfully infect target hosts. However, the underlying mechanisms responsible for hypoxia tolerance in most pathogens are poorly understood. A mitochondrial protein, BbOhmm, is demonstrated to limit oxidative stress resistance and virulence in the insect fungal pathogen, Beauveria bassiana. Here, we found that BbOhmm negatively affected hypoxic adaptation in the insect haemocoel while regulating respiration-related events, heme synthesis and mitochondrial iron homeostasis. A homologue of the mammalian sterol regulatory element-binding proteins (SREBPs), BbSre1, was shown to be involved in BbOhmm-mediated low-oxygen adaptation. Inactivation of BbSre1 resulted in a significant increase in sensitivity to hypoxic and oxidative stress. Similar to ΔBbOhmm, ΔBbSre1 or the ΔBbOhmmΔBbSre1 double mutant accumulated high levels of heme and mitochondrial iron, regulating the similar pathways during hypoxic stress. BbSre1 transcriptional activity and nuclear import were repressed in ΔBbOhmm cells, and affected by intracellular ROS and oxygen levels. These findings have led to a new model in which BbOhmm affects ROS homeostasis in combination with available oxygen to control the transcriptional activity of BbSre1, which in turn mediates low-oxygen adaptation by regulating mitochondrial iron homeostasis, heme synthesis and respiration-implicated genes. This article is protected by copyright. All rights reserved.

4.
Artículo en Inglés | MEDLINE | ID: mdl-31894608

RESUMEN

The synthesis of complex molecules from simple, renewable carbon units is the goal of a sustainable economy. Here we explored the biocatalytic potential of the thiamine diphosphate-dependent (ThDP) oxalyl-CoA decarboxylase (OXC)/2-hydroxyacyl-CoA lyase (HACL) superfamily that naturally catalyze the shortening of acyl-CoA thioester substrates through the release of the C1-unit formyl-CoA. We show that the OXC/HACL superfamily contains promiscuous members that can be reversed to perform nucleophilic C1-extensions of various aldehydes to yield the corresponding 2-hydroxyacyl-CoA thioesters. We improved the catalytic properties of Methylorubrum extorquens OXC by rational enzyme engineering and combined it with two newly described enzymes - a specific oxalyl-CoA synthetase and a 2-hydroxacyl-CoA thioesterase. This enzyme cascade enabled continuous conversion of oxalate and aromatic aldehydes into valuable (S)-α-hydroxy acids with enantiomeric excess up to 99%. Altogether our study showcases the potential to develop ThDP-catalyzed nucleophilic C1-extensions as sustainable production platform for chiral building blocks.

5.
Paediatr Anaesth ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894609

RESUMEN

BACKGROUND: Postoperative nausea vomiting (PONV) after elective outpatient surgery can complicate discharge and increase patient suffering. Within our hospital system, there was variability in the use of PONV prophylaxis for patients undergoing anterior cruciate ligament (ACL) reconstruction, which resulted in variable outcomes. To address this variability, we designed and implemented a standardized PONV prophylaxis guideline for the care of this surgical population. AIM: We sought to develop and implement a standardized PONV prophylaxis guideline for all patients presenting for elective ambulatory ACL reconstruction with the goal of reducing the rate of emesis to less than or equal to 5%. METHODS: We convened a multidisciplinary team to develop a PONV prophylaxis guideline which included administration of dexamethasone, ondansetron, and a low-dose propofol infusion in addition to a femoral and sciatic nerve block and routine ketorolac administration for pain control. Our primary outcome, emesis rate, was tracked using a P-chart. Process measures included use of guideline medications and balancing measures included opioid administration, pain scores, and emergence time. RESULTS: We analyzed PONV outcomes for 817 patients from January 1, 2014, to December 31, 2018. The baseline postoperative emesis rate for all anesthetizing locations was 17%. Following, guideline implementation, the emesis rate decreased to 5%. Opioid administration was decreased following guideline implementation. The percentage of patients managed without any perioperative opioids increased from 16% in the baseline group to 38% following guideline implementation. The P-chart suggests that the observed reduction in emesis rate represents special cause variation and this reduction was sustained over a two-year period. CONCLUSIONS: Implementation of standard PONV guidelines for adolescents undergoing outpatient ACL reconstruction was associated with lower emesis rates. This reduction in emesis rate may have been due to the concurrent reduction in opioids we observed following guideline implementation.

6.
J Cell Biochem ; 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31894610

RESUMEN

The current study was designed to explore the therapeutic effect and mechanism of different extraction, which came from hypoglycemic granule on diabetes-induced liver injury. The ethanol fraction (HGEF) and aqueous fraction (HGAF) from hypoglycemic granule were prepared and administered p.o. to diabetic mice for 17 weeks after 6 weeks of constructing the model. Hematoxylin-eosin (HE) staining and periodic acid-Schiff (PAS) staining were individually applied to observe the morphological change and glycogen deposition. In addition, Oil Red O staining was adopted in lipid droplets detection. Western blot analysis was performed to evaluate the protein expression. The commercial biochemical kits were used to determine the fasting blood glucose value, enzyme activity, and some biochemical indicators. HGEF not only significantly decreased the levels of blood glucose, the content of triglycerides, total cholesterol, low-density lipoprotein, and lipid droplet accumulation, but also remarkably enhanced the high-density lipoprotein, glycogen synthesis, and further improved the hepatic function in diabetic mice. Moreover, HGEF increased the superoxide dismutase (SOD) activity and inhibited the malondialdehyde production, so did HGAF. HGAF performed potential to modulate lipid metabolism via decreasing TG and LDL levels. Further, the protein expressions of SOD, nuclear factor erythroid 2-related factor 2 (Nrf2), and forkhead box O3 (Foxo3a) were increased by HGEF, whereas the receptor-interacting serine-threonine kinase 3 (RIP3), calcium/calmodulin-dependent protein kinase II (CaMKII), and cytochrome c (Cyt c) expressions were inhibited. Our present results suggest that HGEF has superiority in ameliorating oxidative stress via modulating hepatic glycolipid metabolism homeostasis in low-dose streptozotocin-induced liver tissue of diabetic mice.

7.
Am J Primatol ; : e23084, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894611

RESUMEN

In cooperative hunting, a carcass cannot be divided equally, and hunts may be unsuccessful. We studied how chimpanzees respond to these two variables, working for unequal rewards and no rewards, which have been rarely included in experimental cooperative tasks. We presented chimpanzees with a task requiring three chimpanzees to work together and varied the reward structure in two separate experiments. In Experiment 1, two individuals received more rewards than the third, making the outcome unequal. We wanted to know if cooperation would continue or break down, and what mechanisms might maintain performance. Experiment 2 used equal rewards, but this time one or more locations were left unbaited on a proportion of trials. Thus, there was a chance of individuals working to receive nothing. In Experiment 1, the chimpanzees worked at a high rate, tolerating the unequal outcomes, with rank appearing to determine who got access to the higher-value locations. However, equal outcomes (used as a control) enhanced cooperative performance, most likely through motivational processes rather than the absence of inequity aversion. In Experiment 2, performance dropped off dramatically when the chimpanzees were not rewarded on every trial. Their strategy was irrational as donating effort would have led to more rewards in the long run for each individual. Our results lead to a hierarchy of performances by condition with equity > inequity > donating effort. Chimpanzees therefore tolerate mild inequity, but cannot tolerate receiving nothing when others are rewarded.

8.
Rapid Commun Mass Spectrom ; : e8717, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894612

RESUMEN

RATIONALE: Coordinatively driven self-assembly of transition metal ions and bidentate ligands gives rise to organometallic complexes that usually contain superimposed isobars, isomers, and conformers. In this study, the double dispersion ability of ion mobility mass spectrometry (IM-MS) has been utilized to provide a comprehensive structural characterization of the self-assembled supramolecular complexes by their mass and charge, revealed by the MS event, and their shape and collision cross-section (Ω), revealed by the IM event. METHODS: Self-assembled complexes were synthesized by reacting a bis (terpyridine) ligand with a 60o dihedral angle between the two ligating terpyridine sites (T) with divalent Zn, Ni, Cd, or Fe. The products were isolated as [MetalII (T)]n (PF6 )2n salts and analyzed by IM-MS after electrospray ionization (ESI) which produces several charge states from each n-mer, depending on the number of PF6 - anions lost upon ESI. Experimental Ω data, derived via IM-MS, and computational Ω predictions were used to elucidate the size and architecture of the complexes. RESULTS: Only macrocyclic dimers, trimers, and tetramers were observed with Cd (II), whereas Zn (II) formed the same plus hexameric complexes. These two metals led to the simplest product distributions and no linear isomers. In sharp contrast, Ni (II) and Fe (II) formed all possible ring sizes from dimer to hexamer as well as various linear isomers. The experimental and theoretical Ω data indicated rather planar macrocyclic geometries for the dimers and trimers, twisted 3D architectures for the larger rings, and substantially larger sizes with spiral conformation for the linear congeners. Adding PF6 - to the same complex was found to mainly cause size contraction due to new stabilizing anion-cation interactions. CONCLUSIONS: Complete structural identification could be accomplished using ESI-IM-MS. Our results affirm that self-assembly with Cd (II) and Zn (II) proceeds through reversible equilibria that generate the thermodynamically most stable structures, encompassing exclusively macrocyclic architectures that readily accommodate the 60o ligand used. In contrast, complexation with Ni (II) and Fe (II), which form stronger coordinative bonds, proceeds through kinetic control, leading to more complex mixtures and kinetically trapped less stable architectures, such as macrocyclic pentamers and linear isomers.

9.
Clin Anat ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894613

RESUMEN

INTRODUCTION: The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography were investigated via cadaveric dissection in the present study, focusing on the lateral pectoral nerve. MATERIALS AND METHODS: Fifty-eight upper extremities were dissected and the nerve supplies to the deltoid muscle and the variability of the lateral pectoral and axillary nerves, including their topographical patterns, were noted. RESULTS: The clavicular portion of the deltoid muscle received a deltoid branch from the lateral pectoral nerve in 86.2% of cases. Two topographical patterns of the lateral pectoral nerve were observed, depending on the branching level from the brachial plexus: a proximal variant, where the nerve entered the pectoral region undern the clavicle, and a distal variant, where the nerve entered the pectoral region from the axillary fossa around the caudal border of the pectoralis minor. These dissection findings were supported by histological confirmation of peripheral nerve tissue entering the clavicular part of the deltoid muscle. CONCLUSION: The topographical variations of the lateral pectoral nerve are relevant for orthopedic and trauma surgeons and neurologists. These new data could revise the interpretation of deltoid muscle atrophy and of thoracic outlet and pectoralis minor compression syndromes. They could also explain the residual anteversion function of the arm after axillary nerve injury and deficiency, which is often thought to be related to biceps brachii muscle function. This article is protected by copyright. All rights reserved.

10.
Artículo en Inglés | MEDLINE | ID: mdl-31894615

RESUMEN

BACKGROUND: Few studies exist on mental health and neurodevelopmental conditions and service use among youth with intellectual disabilities (IDs), which makes it difficult to develop interventions for this population. The objective of the study is to (1) estimate and compare the prevalence of mental health and neurodevelopmental conditions in youth with and without ID across three developmental stages and (2) estimate and compare mental health service use in youth with and without ID across three developmental stages. METHODS: We conducted secondary data analysis using cross-sectional data collected from caregivers completing the 2011-2012 National Survey of Children's Health. The data set represents a nationally representative sample of youth (0-17 years) in the USA with one child from each household being randomly selected. Data were collected from caregivers in 50 states, Washington D.C. and the US Virgin Islands. We restricted the sample to parents of youth between 3-17 years (N = 81 510). RESULTS: Compared with youth without ID, youth ages 3-17 with ID had a statistically significantly higher prevalence of (1) mental health and neurodevelopmental conditions and (2) mental health care use and medication use for mental health and neurodevelopmental issues (other than attention deficit disorder/attention deficit hyperactivity disorder). Clinically significant differences in coexisting conditions and service use were also found across developmental stages. CONCLUSIONS: Youth with ID are at greater risk of having coexisting mental health and neurodevelopmental conditions than youth without ID and are more likely to receive treatment. Therefore, clinicians should consider mental health and neurodevelopmental conditions and the unique needs of youth by developmental stage when tailoring interventions for youth with ID.

11.
Reprod Domest Anim ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894616

RESUMEN

Minerals in animal feed occur in variable structures, most of which determine the uptake and usage in biological processes in the body. Effective chemical breakdown of minerals may ensure efficient utilisation in metabolism. The aim this study was to evaluate the effects of mineral supplementation on reproduction in cows. A farm was selected for the experiment due to the fact that it previously experienced different reproductive conditions in the farm. The farm comprises cross breed cows with Bonsmara dominating in the farm. Twelve pregnant primiparous and multiparous cows of different ages, parity and weight, that had previously experienced reproductive conditions, were randomly selected for this study. The cows were then randomly sub-divided into two groups (experimental and control group) of six. The experimental group was injected with MULTIMINTM + Se +Cu at a dosage of 1 ml/45 kg BW and Calci 50 p.i. at a dosage of 100 -150 ml/500kg BW at an interval of 6 weeks (from June - October 2017). Blood samples were collected before every injection date. The t-test was used to relate the mean weight gain and serum metabolite between the experimental and control groups. The body weight gain was significantly higher in the experimental group compared to the non-supplemented group. Supplemented cows had significantly (P<0.05) high levels of triglycerides and creatinine kinase. A case of retained placenta and dystocia among non-supplemented cows were noted. Thus, mineral supplementation can be used to improve productivity and reproductive wellbeing.

12.
Am J Primatol ; : e23087, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894614

RESUMEN

Predation risk affects prey species' behavior, even in the absence of a direct threat, but human-induced environmental change may disturb ecologically significant predator-prey interactions. Here, we propose various ways in which knowledge of antipredator tactics, behavioral risk effects, and primate-predator interactions could assist in identifying human-caused disruption to natural systems. Using behavior to evaluate primate responses to the ongoing environmental change should be a potentially effective way to make species conservation more predictive by identifying issues before a more dramatic population declines. A key challenge here is that studies of predation on primates often use data collected via direct observations of habituated animals and human presence can deter carnivores and influence subjects' perception of risk. Hence, we also review various indirect data collection methods to evaluate their effectiveness in identifying where environmental change threatens wild species, while also minimizing observer bias.

13.
Artículo en Inglés | MEDLINE | ID: mdl-31894618

RESUMEN

The ability to harness cellular redox processes for abiotic synthesis might allow the preparation of engineered hybrid living systems. Towards this goal, we describe a new bacteria-mediated Iron-catalysed Reversible Deactivation Radical Polymerisation (RDRP), with a range of metal-chelating agents and monomers that can be used under ambient conditions with a bacterial redox initiation step to generate polymers. Species of bacteria; Cupriavidus metallidurans, Escherichia coli and Clostridium sporogenes were chosen for their redox enzyme systems and evaluated for their ability to induce polymer formation.  Parameters including cell and catalyst concentration, initiator species and monomer type were investigated. Water-soluble synthetic polymers were produced in the presence of the bacteria with full preservation of cell viability. This methodology provides a means by which bacterial redox systems can be exploited to generate 'unnatural' polymers in the presence of 'host' cells, thus setting up the possibility of making natural-synthetic hybrid structures and conjugates.

14.
J Leukoc Biol ; 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31894617

RESUMEN

The pyruvate dehydrogenase complex (PDC)/pyruvate dehydrogenase kinase (PDK) axis directs the universal survival principles of immune resistance and tolerance in monocytes by controlling anabolic and catabolic energetics. Immune resistance shifts to immune tolerance during inflammatory shock syndromes when inactivation of PDC by increased PDK activity disrupts the tricarboxylic acid (TCA) cycle support of anabolic pathways. The transition from immune resistance to tolerance also diverts the TCA cycle from citrate-derived cis-aconitate to itaconate, a recently discovered catabolic mediator that separates the TCA cycle at isocitrate and succinate dehydrogenase (SDH). Itaconate inhibits succinate dehydrogenase and its anabolic role in mitochondrial ATP generation. We previously reported that inhibiting PDK in septic mice with dichloroacetate (DCA) increased TCA cycle activity, reversed septic shock, restored innate and adaptive immune and organ function, and increased survival. Here, using unbiased metabolomics in a monocyte culture model of severe acute inflammation that simulates sepsis reprogramming, we show that DCA-induced activation of PDC restored anabolic energetics in inflammatory monocytes while increasing TCA cycle intermediates, decreasing itaconate, and increasing amino acid anaplerotic catabolism of branched-chain amino acids (BCAAs). Our study provides new mechanistic insight that the DCA-stimulated PDC homeostat reconfigures the TCA cycle and promotes anabolic energetics in monocytes by reducing levels of the catabolic mediator itaconate. It further supports the theory that PDC is an energy sensing and signaling homeostat that restores metabolic and energy fitness during acute inflammation.

15.
Macromol Rapid Commun ; : e1900352, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894619

RESUMEN

The authors describe a process that may eventually reduce the risk of scar formation after glaucoma surgery. For this, a thin hydrogel coating is photochemically generated and linked to the sclera surface at the surgical site. This coating is generated from a photoreactive prepolymer containing anthraquinone groups, which is administered as a thin pad to the sclera surface. Short UV irradiation leads to a reaction of the photogroups with neighboring chains via C-H insertion crosslinking, thus transforming the precursor polymer into a hydrogel. Simultaneously, a reaction between the photogroups and the underlying sclera tissue occurs, so that the hydrogel patch becomes covalently linked to the tissue. The authors show that the resulting thin coating is strongly cell repellent and hinders tenon fibroblasts to form tenon tissue at the site of the coating and is suitable for inclusion into a surgical procedure.

16.
Artículo en Inglés | MEDLINE | ID: mdl-31894620

RESUMEN

Low back pain (LBP) remains one of the major public health problems worldwide. However, in low-income countries, such as those in Africa, the epidemiological data on healthcare utilisation for LBP are lacking due to more pressing problems such as infectious diseases, to which the majority of health resources are channelled. Therefore, this study aimed at investigating the determinants of healthcare utilisation for LBP in the general population of Ethiopia. A population-based cross-sectional study was conducted in South-West Shewa zone of Ethiopia from June to November 2018. The data were collected by interviewing adults with LBP (n = 1812, randomly selected) using a psychometrically tested and validated instrument, analysed using R version 3.5.1. A log-binomial regression model was used to determine the prevalence ratio with a 95% confidence interval (CI) in identifying factors associated with healthcare utilisation for LBP. Estimates of population parameters were also presented with 95% CIs and p values. For all applications of inferential statistics, a p value of ≤.05 was taken as the significance level. The lifetime prevalence of healthcare utilisation for LBP was 36.1%, 95% CI: 33.9-38.1, while the annual prevalence rate was 30%, 95% CI: 27.9-32.2. Of those with a 1-year history of healthcare utilisation, while 7.4%, 95% CI: 4.9-10.3 rural and 36.6%, 95% CI: 29.5-44 urban populations utilised healthcare from general hospitals, 1.4%, 95% CI: 0.3-2.7 rural and 6.8%, 95% CI: 3.1-10.8 urban populations utilised healthcare from specialised hospitals. Several sociodemographic factors, modifiable health behaviours/lifestyle habits, pain interrelated factors, and specific factors such as beliefs about the pain, depressive symptoms and insomnia were associated with healthcare utilisation for LBP. The implications of this research are that it may be prudent for the Ethiopian healthcare policy makers to develop the necessary strategies to meet the health needs of both urban and rural populations with LBP.

17.
Chemistry ; 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31894622

RESUMEN

Benzynes were selectively generated in-situ from phenols and trapped regioselectively by potassium hexamethyldisilazide to form primary anilines following acidic workup. The direct conversion of a phenolic hydroxyl group to a free amino group is a useful method for the preparation of primary aryl amines that are hard to synthesize using coupling reactions involving phenol derivatives with ammonia. While reactions of ortho - and meta -substituted phenols produced meta-substituted anilines exclusively, those of para -substituted phenols provided ortho -silylanilines.

18.
Dev Sci ; 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894624

RESUMEN

The development of cognitive control enables children to better resist acting based on distracting information that interferes with the current action. Cognitive control improvement serves different functions that differ in part by the type of interference to resolve. Indeed, resisting to interference at the task-set level or at the response-preparation level is respectively associated with cognitive flexibility and inhibition. It is, however, unknown whether the same neural mechanism underlies these two functions across development. Studies in adults have revealed the contribution of mid-frontal theta (MFT) oscillations in interference resolution. This study investigated whether MFT is involved in the resolution of different types of interference in two age groups identified as corresponding to different latent structures of executive functions. Preschool (4-6 years) and school children (6-8 years) were tested with a task involving interference at the response level and/or the task-set level while EEG was recorded. Behaviorally, response time and accuracy were affected by task-set. Both age groups were less accurate when the interference occurred at the task-set level and only the younger group showed decreased accuracy when interference was presented at the response-preparation level. Furthermore, MFT power was increased, relative to the baseline, during the resolution of both types of interference and in both age groups. These findings suggest that MFT is involved in immature cognitive control (i.e, preschool and school-ages), by orchestrating its different cognitive processes, irrespective of the interference to resolve and of the level of cognitive control development (i.e. the degree of differentiation of executive functions).

19.
Chemphyschem ; 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31894625

RESUMEN

Directing the self-assembly of organic building blocks with 2D templates has been a promising method to create molecular superstructures having unique physicochemical properties. In this work the on-surface self-assembly of simple ditopic functional molecules confined inside periodic nanotemplates was modeled by means of the lattice Monte Carlo simulation method. Two types of confinement, that is honeycomb porous networks and parallel grooves of controlled diameter and width were used in the calculations. Additionally, the effect of (pro)chirality of the adsorbing molecules on the outcome of the templated self-assembly was examined. To that end, enantiopure and racemic assemblies were studied and the resulting structures were identified and classified. The obtained findings demonstrated that suitable tuning of the structural parameters of the templates enables directing the self-assembly towards linear and cyclic aggregates with controlled size. Moreover, chiral resolution of the molecular conformers using honeycomb networks with adjusted pore size was found possible. Our theoretical predictions can be helpful in designing structured surfaces to direct self-assembly and polymerization of organic functional building blocks.

20.
Artículo en Inglés | MEDLINE | ID: mdl-31894626

RESUMEN

Derivatives of 4-aminomethyl-L-phenylalanine having aromatic oligoamide foldamers as side chain appendages were successfully charged on tRNA by means of flexizymes. Their subsequent ribosomal incorporation both at the C-terminus of, and within, peptide sequences, was demonstrated. These results expand the registry of chemical structures tolerated by the ribosome machinery to side-chains significantly larger and more structurally defined than was previously known.

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