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1.
J Colloid Interface Sci ; 674: 560-575, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38945024

RESUMO

The present paper reports the fabrication of novel types of hybrid fibrous photocatalysts by combining block copolymer (BCP) templating, sol-gel processing, and coaxial electrospinning techniques. Coaxial electrospinning produces core-shell nanofibers (NFs), which are converted into hollow porous TiO2 NFs using an oxidative calcination step. Hybrid BCP micelles comprising a single plasmonic nanoparticle (NP) in their core and thereof derived silica-coated core-shell particles are utilized as precursors to generate yolk-shell type particulate inclusions in photocatalytically active NFs. The catalytic and photocatalytic activity of calcined NFs comprising different types of yolk-shell particles is systematically investigated and compared. Interestingly, calcined NFs comprising silica-coated yolk-shells demonstrate enhanced catalytic and photocatalytic performance despite the presence of silica shell separating plasmonic NP from the TiO2 matrix. Electromagnetic simulations indicate that this enhancement is caused by a localized surface plasmon resonance and a confinement effect in silica-coated yolk-shells embedded in porous TiO2 NFs. Utilization of the coaxially electrospun TiO2 NFs in combination with yolk-shells comprising plasmonic NPs reveals to be a potent method for the photocatalytic decomposition of numerous pollutants. It is worth noting that this study stands as the first occurrence of combining yolk-shells (Au@void@SiO2) with porous electrospun NFs (TiO2) for photocatalytic purposes and gaining an understanding of plasmon and confinement effects for photocatalytic performance. This approach represents a promising route for fabricating highly active and up-scalable fibrous photocatalytic systems.

2.
Ann Surg Open ; 5(2): e452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38911625

RESUMO

Up to hundreds of billions of dollars are annually lost to fraud and abuse in the US health care, making it a significant burden on the system. This study investigates a specific instance of health care fraud in spine surgery, in which a medical device company ended up paying $75 million to settle violations of the False Claims Act. We review the surgical background regarding the kyphoplasty procedure, as well as its billing and reimbursement details. We also explore the official legal complaint brought by the US Department of Justice to tell the story of how one of the most significant medical innovations in spine surgery in the 21st century turned into a widespread fraudulent marketing scheme. In the sequence, we provide a detailed root cause analysis of this scandal and propose some proactive measures that can be taken to avoid such type of unfortunate events. Ultimately, this historical health care scandal constitutes a valuable lesson to surgeons, health care administrators, medical device companies, and policymakers on how misaligned incentives and subsequent unscrupulous practices can transform a medical innovation into an unfortunate tale of fraud and deceit.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38914103

RESUMO

Hybrid perovskites are a rapidly growing research area, having reached photovoltaic power conversion efficiencies of over 25 %. There is a increasing consensus that the structures of these materials, and hence their electronic structures, can not be understood purely from the time and space averaged crystal structures observable by conventional methods. We apply a symmetry-motivated analysis method to analyse X-ray pair distribution function data of the cubic phases of the hybrid perovskites MAPb$X_3$ ($X$ = I, Br, Cl). We demonstrate that, even in the cubic phase, the local structure of the inorganic components of MAPb$X_3$ ($X$ = I, Br, Cl), are dominated by scissoring type deformations of the Pb$X_6$ octahedra. We find these modes to have a larger amplitude than equivalent distortions in the $A$-site deficient perovskite ScF$_3$ and demonstrate that they show a significant departure from the harmonic approximation. Calculations performed on an inorganic perovskite analogue, FrPbBr3show that the large amplitudes of the scissoring modes are coupled to a dynamic opening of the electronic band gap. Finally, we use density functional theory calculations to show that the organic MA cations reorientate to accommodate the large amplitude scissoring modes.

4.
Angew Chem Int Ed Engl ; : e202406742, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842522

RESUMO

A selective deelectronation reagent with very high potential of +2.00 (solution) / +2.41 V (solid-state) vs. Fc+/0 and based on a room temperature stable perfluoronaphthalene (naphthaleneF) radical cation salt was developed and applied. The solid-state deelectronation of commercial naph-tha-leneF with [NO]+[F{Al(ORF)3}2]- generates [naphthaleneF]+∙[F{Al(ORF)3}2]- (ORF = OC(CF3)3) in gram scale. Thermo-chemical analysis unravels the solid-state de-electronation potential of the starting [NO]+-reagent to be +2.34 V vs. Fc+/0 with [F{Al(ORF)3}2]- counterion, but only +1.14 V vs. Fc+/0 with the small [SbF6]- ion. Selective reactions demonstrate the selectivity of [naphthaleneF]+∙ for deelectronation of a multitude of organ(ometall)ic molecules and elements in solution: providing the molecular struc-tures of the acene dications [tetracene]2+, [pentacene]2+ or spectroscopic evi-dence for the carbo-nyl complex of the ferrocene dication [Fc(CO)]2+, the [P9]+ cation from white phosphor-us, the solvent-free copper(I) salt starting from copper metal and the dicationic Fe(IV)-scorpionate complex [Fe(sc)2]2+.

5.
J Am Chem Soc ; 146(23): 16203-16212, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38829274

RESUMO

Baeyer-Villiger monooxygenases (BVMOs) play crucial roles in the core-structure modification of natural products. They catalyze lactone formation by selective oxygen insertion into a carbon-carbon bond adjacent to a carbonyl group (Baeyer-Villiger oxidation, BVO). The homologous bacterial BVMOs, BraC and PxaB, thereby process bicyclic dihydroindolizinone substrates originating from a bimodular nonribosomal peptide synthetase (BraB or PxaA). While both enzymes initially catalyze the formation of oxazepine-dione intermediates following the identical mechanism, the final natural product spectrum diverges. For the pathway involving BraC, the exclusive formation of lipocyclocarbamates, the brabantamides, was reported. The pathway utilizing PxaB solely produces pyrrolizidine alkaloids, the pyrrolizixenamides. Surprisingly, replacing pxaB within the pyrrolizixenamide biosynthetic pathway by braC does not change the product spectrum to brabantamides. Factors controlling this product selectivity have remained elusive. In this study, we set out to solve this puzzle by combining the total synthesis of crucial pathway intermediates and anticipated products with in-depth functional in vitro studies on both recombinant BVMOs. This work shows that the joint oxazepine-dione intermediate initially formed by both BVMOs leads to pyrrolizixenamides upon nonenzymatic hydrolysis, decarboxylative ring contraction, and dehydration. Brabantamide biosynthesis is enzyme-controlled, with BraC efficiently transforming all the accepted substrates into its cognate final product scaffold. PxaB, in contrast, shows only considerable activity toward brabantamide formation for the substrate analog with a natural brabantamide-type side chain structure, revealing substrate-controlled product selectivity.


Assuntos
Oxigenases de Função Mista , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Alcaloides/química , Alcaloides/metabolismo , Biocatálise , Estrutura Molecular , Especificidade por Substrato
6.
Dalton Trans ; 53(23): 9909-9920, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38808483

RESUMO

Inspired by the well-studied mononuclear spin crossover compound [Fe(H2B(pz)2)2(bipy)], the bipyridine-based bisbidentate ligands 1,2-di(2,2'-bipyridin-5-yl)ethyne (ac(bipy)2) and 1,4-di(2,2'-bipyridine-5-yl)-3,5-dimethoxybenzene (Ph(OMe)2(bipy)2) are used to bridge two [Fe(H2B(pz)2)2] units, leading to the charge-neutral dinuclear iron(II) compounds [{Fe(H2B(pz)2)2}2 µ-(ac(bipy)2)] (1) and [{Fe(H2B(pz)2)2}2 µ-(Ph(OMe)2(bipy)2)] (2), respectively. The spin-crossover properties of these molecules are investigated by temperature-dependent PPMS measurements, Mössbauer, vibrational and UV/Vis spectroscopy as well as X-ray absorption spectroscopy. While compound 1 undergoes complete SCO with T1/2 = 125 K, an incomplete spin transition is observed for 2 with an inflection point at 152 K and a remaining high-spin fraction of 40% below 65 K. The spin transitions of the dinuclear compounds are also more gradual than for the parent compound [Fe(H2B(pz)2)2(bipy)]. This is attributed to steric hindrance between the molecules, limiting intermolecular interactions such as π-π-stacking.

7.
Commun Biol ; 7(1): 655, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806706

RESUMO

The gut microbiota influences human health and the development of chronic diseases. However, our understanding of potentially protective or harmful microbe-host interactions at the molecular level is still in its infancy. To gain further insights into the hidden gut metabolome and its impact, we identified a cryptic non-ribosomal peptide BGC in the genome of Bacillus cereus DSM 28590 from the mouse intestine ( www.dsmz.de/miBC ), which was predicted to encode a thiazol(in)e substructure. Cloning and heterologous expression of this BGC revealed that it produces bacillamide D. In-depth functional evaluation showed potent cytotoxicity and inhibition of cell migration using the human cell lines HCT116 and HEK293, which was validated using primary mouse organoids. This work establishes the bacillamides as selective cytotoxins from a bacterial gut isolate that affect mammalian cells. Our targeted structure-function-predictive approach is demonstrated to be a streamlined method to discover deleterious gut microbial metabolites with potential effects on human health.


Assuntos
Bacillus cereus , Microbioma Gastrointestinal , Bacillus cereus/metabolismo , Bacillus cereus/genética , Animais , Camundongos , Humanos , Células HEK293 , Citotoxinas/metabolismo , Citotoxinas/genética , Células HCT116 , Intestinos/microbiologia , Movimento Celular , Organoides/metabolismo
8.
Genet Sel Evol ; 56(1): 41, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773363

RESUMO

BACKGROUND: Breeding programs are judged by the genetic level of animals that are used to disseminate genetic progress. These animals are typically the best ones of the population. To maximise the genetic level of very good animals in the next generation, parents that are more likely to produce top performing offspring need to be selected. The ability of individuals to produce high-performing progeny differs because of differences in their breeding values and gametic variances. Differences in gametic variances among individuals are caused by differences in heterozygosity and linkage. The use of the gametic Mendelian sampling variance has been proposed before, for use in the usefulness criterion or Index5, and in this work, we extend existing approaches by not only considering the gametic Mendelian sampling variance of individuals, but also of their potential offspring. Thus, the criteria developed in this study plan one additional generation ahead. For simplicity, we assumed that the true quantitative trait loci (QTL) effects, genetic map and the haplotypes of all animals are known. RESULTS: In this study, we propose a new selection criterion, ExpBVSelGrOff, which describes the genetic level of selected grand-offspring that are produced by selected offspring of a particular mating. We compare our criterion with other published criteria in a stochastic simulation of an ongoing breeding program for 21 generations for proof of concept. ExpBVSelGrOff performed better than all other tested criteria, like the usefulness criterion or Index5 which have been proposed in the literature, without compromising short-term gains. After only five generations, when selection is strong (1%), selection based on ExpBVSelGrOff achieved 5.8% more commercial genetic gain and retained 25% more genetic variance without compromising inbreeding rate compared to selection based only on breeding values. CONCLUSIONS: Our proposed selection criterion offers a new tool to accelerate genetic progress for contemporary genomic breeding programs. It retains more genetic variance than previously published criteria that plan less far ahead. Considering future gametic Mendelian sampling variances in the selection process also seems promising for maintaining more genetic variance.


Assuntos
Modelos Genéticos , Locos de Características Quantitativas , Seleção Genética , Animais , Cruzamento/métodos , Feminino , Masculino , Seleção Artificial
9.
Neurol Res Pract ; 6(1): 25, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38693574

RESUMO

BACKGROUND: Motor and vocal tics are the main symptom of Gilles de la Tourette-syndrome (GTS). A particular complex vocal tic comprises the utterance of swear words, termed coprolalia. Since taboo words are socially inappropriate, they are normally suppressed by people, which implies cognitive control processes. METHOD: To investigate the control of the unintentional pronunciation of taboo words and the associated processes of conflict monitoring, we used the "Spoonerisms of Laboratory Induced Predisposition" (SLIP) paradigm. Participants read multiple inductor word pairs with the same phonemes, followed by pronouncing a target pair with inverse phonemes. This led to a conflict between two competing speech plans: the correct word pair and the word pair with inverted phonemes. Latter speech error, a spoonerism, could result in a neutral or taboo word. We investigated 19 patients with GTS and 23 typically developed controls (TDC) and measured participants' electroencephalography (EEG) during the SLIP task. RESULTS: At the behavioral level less taboo than neutral word spoonerisms occurred in both groups without significant differences. Event-related brain potentials (ERP) revealed a difference between taboo and neutral word conditions in the GTS group at the midline electrodes in a time range of 250-400 ms after the speech prompt, which was not found in the TDC group. The extent of this effect depended on the number of inductor word pairs, suggesting an increasing level of cognitive control in the GTS group. CONCLUSION: The differences between taboo and neutral word conditions in patients with GTS compared to TDC suggest an altered recruitment of cognitive control processes in GTS, likely enlisted to suppress taboo words.

10.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615240

RESUMO

The mismatch negativity and the P3a of the event-related EEG potential reflect the electrocortical response to a deviant stimulus in a series of stimuli. Although both components have been investigated in various paradigms, these paradigms usually incorporate many repetitions of the same deviant, thus leaving open whether both components vary as a function of the deviant's position in a series of deviant stimuli-i.e. whether they are subject to qualitative/quantitative habituation from one instantiation of a deviant to the next. This is so because the detection of mismatch negativity/P3a in the event-related EEG potential requires an averaging over dozens or hundreds of stimuli, i.e. over many instantiations of the deviant per participant. The present study addresses this research gap. We used a two-tone oddball paradigm implementing only a small number of (deviant) stimuli per participant, but applying it to a large number of participants (n > 230). Our data show that the mismatch negativity amplitude exhibits no decrease as a function of the deviant's position in a series of (standard and) deviant stimuli. Importantly, only after the very first deviant stimulus, a distinct P3a could be detected, indicative of an orienting reaction and an attention shift, and thus documenting a dissociation of mismatch negativity and P3a.


Assuntos
Cafeína , Habituação Psicofisiológica , Humanos , Potenciais Evocados , Eletroencefalografia
11.
ACS Nano ; 18(17): 11025-11041, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38626916

RESUMO

ALK-positive NSCLC patients demonstrate initial responses to ALK tyrosine kinase inhibitor (TKI) treatments, but eventually develop resistance, causing rapid tumor relapse and poor survival rates. Growing evidence suggests that the combination of drug and immune therapies greatly improves patient survival; however, due to the low immunogenicity of the tumors, ALK-positive patients do not respond to currently available immunotherapies. Tumor-associated macrophages (TAMs) play a crucial role in facilitating lung cancer growth by suppressing tumoricidal immune activation and absorbing chemotherapeutics. However, they can also be programmed toward a pro-inflammatory tumor suppressive phenotype, which represents a highly active area of therapy development. Iron loading of TAMs can achieve such reprogramming correlating with an improved prognosis in lung cancer patients. We previously showed that superparamagnetic iron oxide nanoparticles containing core-cross-linked polymer micelles (SPION-CCPMs) target macrophages and stimulate pro-inflammatory activation. Here, we show that SPION-CCPMs stimulate TAMs to secrete reactive nitrogen species and cytokines that exert tumoricidal activity. We further show that SPION-CCPMs reshape the immunosuppressive Eml4-Alk lung tumor microenvironment (TME) toward a cytotoxic profile hallmarked by the recruitment of CD8+ T cells, suggesting a multifactorial benefit of SPION-CCPM application. When intratracheally instilled into lung cancer-bearing mice, SPION-CCPMs delay tumor growth and, after first line therapy with a TKI, halt the regrowth of relapsing tumors. These findings identify SPIONs-CCPMs as an adjuvant therapy, which remodels the TME, resulting in a delay in the appearance of resistant tumors.


Assuntos
Crizotinibe , Neoplasias Pulmonares , Nanopartículas Magnéticas de Óxido de Ferro , Microambiente Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Nanopartículas Magnéticas de Óxido de Ferro/química , Humanos , Camundongos , Crizotinibe/farmacologia , Crizotinibe/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Linhagem Celular Tumoral , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino
12.
Compr Psychiatry ; 132: 152482, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38603938

RESUMO

INTRODUCTION: Theoretical frameworks of behavioral addictions mostly acknowledge the role of stress in the development and maintenance of these disorders, models of compulsive buying-shopping disorder (CBSD) however rarely incorporated stress. The association between stress and CBSD has not been reviewed yet. METHODS: A scoping review was conducted to evaluate empirical results on the association between stress and CBSD. A comprehensive search string was employed in three databases. RESULTS: 16 studies were included. Correlative studies suggested significant correlations between general perceived stress and CBSD symptom severity. Studies involving mean comparisons found higher general perceived stress levels in persons with problematic buying-shopping behavior/CBSD compared to control participants (large effects). Mixed results were found in studies involving regression/structural equation models and ecological momentary assessments. One study with a stress/negative mood induction observed more CBSD symptoms in a high stress group compared to a low stress group. DISCUSSION: The studies are heterogeneous concerning design, samples and measures. Only very few studies surpass the level of cross-sectional correlative data which limits the ability to draw clear conclusions. Future research should study the impact of experimentally induced stress on CBSD symptoms, examine the relationship between stress and CBSD longitudinally and assess objective stress markers.


Assuntos
Comportamento Compulsivo , Estresse Psicológico , Humanos , Estresse Psicológico/psicologia , Estresse Psicológico/complicações , Comportamento Compulsivo/psicologia , Comportamento Aditivo/psicologia
13.
Biotechnol J ; 19(4): e2300505, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38651269

RESUMO

Chinese hamster ovary (CHO) cells are the commonly used mammalian host system to manufacture recombinant proteins including monoclonal antibodies. However unfavorable non-human glycoprofile displayed on CHO-produced monoclonal antibodies have negative impacts on product quality, pharmacokinetics, and therapeutic efficiency. Glycoengineering such as genetic elimination of genes involved in glycosylation pathway in CHO cells is a viable solution but constrained due to longer timeline and laborious workflow. Here, in this proof-of-concept (PoC) study, we present a novel approach coined CellEDIT to engineer CHO cells by intranuclear delivery of the CRISPR components to single cells using the FluidFM technology. Co-injection of CRISPR system targeting BAX, DHFR, and FUT8 directly into the nucleus of single cells, enabled us to generate triple knockout CHO-K1 cell lines within a short time frame. The proposed technique assures the origin of monoclonality without the requirement of limiting dilution, cell sorting or positive selection. Furthermore, the approach is compatible to develop both single and multiple knockout clones (FUT8, BAX, and DHFR) in CHO cells. Further analyses on single and multiple knockout clones confirmed the targeted genetic disruption and altered protein expression. The knockout CHO-K1 clones showed the persistence of gene editing during the subsequent passages, compatible with serum free chemically defined media and showed equivalent transgene expression like parental clone.


Assuntos
Sistemas CRISPR-Cas , Cricetulus , Edição de Genes , Células CHO , Animais , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Anticorpos Monoclonais/genética , Proteínas Recombinantes/genética , Técnicas de Inativação de Genes/métodos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Cricetinae , Engenharia Genética/métodos
14.
World Neurosurg ; 185: 393-402.e27, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38437980

RESUMO

BACKGROUND: Despite the ubiquitous use of the Glasgow Coma Scale (GCS) worldwide, no study to date has objectively and quantitatively assessed its impact on the scientific literature and clinical practice. Therefore, we comprehensively analyzed scientific publications and clinical practice guidelines employing the GCS to gauge its clinical and academic impact, identify research hotspots, and inform future research on the topic. METHODS: A cross-sectional bibliometric analysis was performed on Scopus to obtain relevant publications incorporating the GCS from 1974 to 2022. In addition, a systematic review of existing clinical practice guidelines in PubMed, Scopus, Web of Science, and Trip Database was performed. Validated bibliometric parameters including article title, journal, publication year, authors, citation count, country, institution, keywords, impact factor, and references were assessed. When evaluating clinical practice guidelines, the sponsoring organization, country of origin, specialty, and publication year were assessed. RESULTS: A total of 37,633 articles originating from 3924 different scientific journals spanning 1974-2022 were included in the final analysis. The compound annual growth rate of publications referencing the GCS was 16.7%. Of 104 countries, the United States had the highest total number of publications employing the GCS (n = 8517). World Neurosurgery was the scientific periodical with the highest number of publications on the GCS (n = 798). The top trending author-supplied keyword was "traumatic brain injury" (n = 3408). The 97 included clinical practice guidelines most commonly employed the GCS in the fields of internal medicine (n = 22, 23%), critical care (n = 21, 22%), and neurotrauma (n = 19, 20%). CONCLUSIONS: At the turn of the 50th anniversary of the GCS, we provided a unique and detailed description of the "path to success" of the GCS both in terms of its scientific and clinical impact. These results have not only a historical but also an important didactic value. Ultimately our detailed analysis, which revealed some of the factors that led the GCS to become such a widespread and highly influential score, may assist future researchers in their development of new outcome measures and clinical scores, especially as such tools become increasingly relevant in an evidence-based data-driven age.


Assuntos
Bibliometria , Escala de Coma de Glasgow , Guias de Prática Clínica como Assunto , Humanos , Estudos Transversais
15.
Commun Chem ; 7(1): 39, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402292

RESUMO

The sorbicillinoid family is a large class of natural products known for their structural variety and strong, diverse biological activities. A special member of this family, sorbicillactone A, the first nitrogen-containing sorbicillinoid, exhibits potent anti-leukemic and anti-HIV activities and possesses a unique structure formed from sorbicillinol, alanine, and fumaric acid building blocks. To facilitate in-depth biological and structure-activity relationship studies of this promising natural product, we developed a chemoenzymatic approach that provides access to sorbicillactone A and several analogs with excellent yields under precise stereochemical control. The key steps of the highly convergent, stereoselective, and short route are the enantioselective oxidative dearomatization of sorbillin to sorbicillinol catalyzed by the enzyme SorbC and the subsequent Michael addition of a fumarylazlactone building block. Additionally, our synthetic findings and bioinformatic analysis suggest that sorbicillactone A is biosynthetically formed analogously.

16.
Chemistry ; 30(21): e202400105, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38299788

RESUMO

Partial ligand substitution at the iron pentacarbonyl radical cation generates novel half-sandwich complexes of the type [Fe(η6-arene)(CO)2]⋅+ (arene=1,3,5-tri-tert-butylbenzene, 1,3,5-trimethylbenzene, benzene and fluorobenzene). Of those, the bulkier 1,3,5-tri-tert-butylbenzene (mes*) derivative [Fe(mes*)(CO)2]⋅+ was fully characterized by XRD analysis, IR, NMR, cw-EPR, Mössbauer spectroscopy and cyclic voltammetry as the [Al(ORF)4]- (RF=C(CF3)3) salt. Chemical electronation, i. e., the single electron reduction, with decamethylferrocene generates neutral [Fe(mes*)(CO)2], whereas further deelectronation under CO-pressure leads to a dicationic three-legged [Fe(mes*)(CO)3]2+ salt with [Al(ORF)4]- counterion. The full substitution of the carbonyl ligands in [Fe(CO)5]⋅+[Al(ORF)4]- mainly resulted in disproportionation reactions, giving solid Fe(0) and the dicationic bis-arene salts [Fe(η6-arene)2]2+([Al(ORF)4]-)2 (arene=1,3,5-trimethylbenzene, benzene and fluorobenzene). Only by employing the very large fluoride bridged anion [F-{Al(ORF)3}2]-, it was possible to isolate an open shell bis-arene cation salt [Fe(C6H6)2]⋅+[F-{Al(ORF)3}2]-. The highly reactive cation was characterized by XRD analysis, cw-EPR, Mössbauer spectroscopy and cyclic voltammetry. The disproportionation of [Fe(C6H6)2]⋅+ salts to give solid Fe(0) and [Fe(C6H6)2]2+ salts was analyzed by a suitable cycle, revealing that the thermodynamic driving force for the disproportionation is a function of the size of the anion used and the polarity of the solvent.

17.
Science ; 383(6690): eabn3263, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422184

RESUMO

Vocal production learning ("vocal learning") is a convergently evolved trait in vertebrates. To identify brain genomic elements associated with mammalian vocal learning, we integrated genomic, anatomical, and neurophysiological data from the Egyptian fruit bat (Rousettus aegyptiacus) with analyses of the genomes of 215 placental mammals. First, we identified a set of proteins evolving more slowly in vocal learners. Then, we discovered a vocal motor cortical region in the Egyptian fruit bat, an emergent vocal learner, and leveraged that knowledge to identify active cis-regulatory elements in the motor cortex of vocal learners. Machine learning methods applied to motor cortex open chromatin revealed 50 enhancers robustly associated with vocal learning whose activity tended to be lower in vocal learners. Our research implicates convergent losses of motor cortex regulatory elements in mammalian vocal learning evolution.


Assuntos
Elementos Facilitadores Genéticos , Eutérios , Evolução Molecular , Regulação da Expressão Gênica , Córtex Motor , Neurônios Motores , Proteínas , Vocalização Animal , Animais , Quirópteros/genética , Quirópteros/fisiologia , Vocalização Animal/fisiologia , Córtex Motor/citologia , Córtex Motor/fisiologia , Cromatina/metabolismo , Neurônios Motores/fisiologia , Laringe/fisiologia , Epigênese Genética , Genoma , Proteínas/genética , Proteínas/metabolismo , Sequência de Aminoácidos , Eutérios/genética , Eutérios/fisiologia , Aprendizado de Máquina
18.
Eur Heart J Acute Cardiovasc Care ; 13(5): 401-410, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38366232

RESUMO

AIMS: While prognosis of acute myocarditis with uncomplicated presentation is perceived as benign, data on long-term outcomes are scarce. We evaluated rates of myocarditis-associated cardiovascular events after a first-time hospitalization with uncomplicated acute myocarditis in patients without known heart disease. METHODS AND RESULTS: In this retrospective nationwide population-based cohort study from 2013 to 2020, hospitalized patients with uncomplicated acute myocarditis but without known heart disease were 1:1 propensity score-matched with surgical controls hospitalized for laparoscopic appendectomy. As assessed in time-to-event analyses, the primary outcome was a composite of rehospitalization for myocarditis, pericardial disease, heart failure and its complications, arrhythmias, implantation of cardiac devices, and heart transplant. After matching, we identified 1439 patients with uncomplicated acute myocarditis (median age of 35 years, 74.0% male) and 1439 surgical controls (median age of 36 years, 74.4% male). Over a median follow-up of 39 months, compared with surgical controls, the hazard ratio for the primary composite outcome was 42.3 [95% confidence interval (CI) 17.4-102.8], corresponding to an incidence rate of 43.7 vs. 0.9 per 1000 patient-years (py) and an incidence rate difference of 42.7 (95% CI 36.7-48.8) per 1000 py. CONCLUSION: Patients hospitalized with uncomplicated acute myocarditis and no known prior heart disease were associated with substantial risk for cardiovascular events over a follow-up of up to 8 years. This calls for a more efficient therapeutic management of this population of patients.


Assuntos
Miocardite , Humanos , Miocardite/epidemiologia , Miocardite/complicações , Masculino , Feminino , Adulto , Estudos Retrospectivos , Incidência , Seguimentos , Prognóstico , Doença Aguda , Fatores de Tempo , Pessoa de Meia-Idade , Pontuação de Propensão , Hospitalização/estatística & dados numéricos , Fatores de Risco
20.
Langmuir ; 40(5): 2487-2499, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38180486

RESUMO

The solvophobicity-driven directional self-assembly of polymer-coated gold nanorods is a well-established phenomenon. Yet, the kinetics of this process, the origin of site-selectivity in the self-assembly, and the interplay of (attractive) solvophobic brush interactions and (repulsive) electrostatic forces are not fully understood. Herein, we use a combination of time-resolved (vis/NIR) extinction spectroscopy and finite-difference time-domain (FDTD) simulations to determine conversion profiles for the assembly of gold nanorods with polystyrene shells of distinct thicknesses into their (tip-to-tip) self-assembled structures. In particular, we demonstrate that the assembly process is highly protracted compared with diffusion-controlled rates, and we find that the assembly rate varies for different thickness values of the polymer shell. Our findings were rationalized using coarse-grained molecular dynamics simulations, which also corroborated the tip-to-tip preference in the self-assembly process, albeit with a uniform polymer coating. Utilizing the knowledge of quantified conversion rates for distinct colloidal species, we designed coassembling systems with different brush thicknesses, featuring "narcissistic" self-sorting behavior. This provides new perspectives for high-level supracolloidal self-assembly.

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