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1.
ACS Omega ; 9(18): 20467-20476, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38737022

RESUMEN

Molecular and dissociative hydrogen adsorption of transition metal (TM)-doped [Mo3S13]2- atomic clusters were investigated using density functional theory calculations. The introduced TM dopants form stable bonds with S atoms, preserving the geometric structure. The S-TM-S bridging bond emerges as the most stable configuration. The preferred adsorption sites were found to be influenced by various factors, such as the relative electronegativity, coordination number, and charge of the TM atom. Notably, the presence of these TM atoms remarkably improved the hydrogen adsorption activity. The dissociation of a single hydrogen molecule on TM[Mo3S13]2- clusters (TM = Sc, Cr, Mn, Fe, Co, and Ni) is thermodynamically and kinetically favorable compared to their bare counterparts. The extent of favorability monotonically depends on the TM impurity, with a maximum activation barrier energy ranging from 0.62 to 1.58 eV, lower than that of the bare cluster (1.69 eV). Findings provide insights for experimental research on hydrogen adsorption using TM-doped molybdenum sulfide nanoclusters, with potential applications in the field of hydrogen energy.

2.
ACS Omega ; 9(18): 20056-20065, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38737018

RESUMEN

Graphene quantum dots have been widely studied owing to their unique optical, electrical, and optoelectrical properties for various applications in solar devices. Here, we investigate the optoelectronic properties of hexagonal and nitrogen-doped graphene quantum dots using the first-principles method. We find that doping nitrogen atoms to hexagonal graphene quantum dots results in a significant red shift toward the visible light range as compared to that of the pristine graphene quantum dots, and the doped nitrogen atoms also induce a clear signature of anisotropy of the frontier orbitals induced by the electron correlation between the doped nitrogen atoms and their adjacent carbon atoms. Moreover, time-dependent density functional theory calculations with the M06-2X functional and 6-311++G(d,p) basis set reproduce well the experimental absorption spectra reported recently. These results provide us with a novel approach for more systematic investigations on next-generation solar devices with assembled quantum dots to improve their light selectivity as well as efficiency.

3.
Appl Clin Genet ; 17: 47-56, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38737445

RESUMEN

Background: Androgen resistance syndrome or androgen insensitivity syndrome (AIS - Androgen Insensitivity Syndrome, OMIM 300068) is an X-linked recessive genetic syndrome causing disorders of sexual development in males. This disease is caused by mutations in the AR gene located on the X chromosome, which encodes the protein that structures the androgen receptor, with the role of receiving androgens. Mutation of the AR gene causes complete or partial loss of androgen receptor function, thereby androgen not being obtained and exerting its effect on target organs, resulting in abnormalities of the male reproductive system due to this organ system, differentiating towards feminization under the influence of estrogen. Disease prevention can be achieved by using pre-implantation genetic diagnosis, which enables couples carrying the mutation to have healthy offspring. Aim: To carry out preimplantation genetic diagnosis of androgen resistance syndrome. Methods: Sanger sequencing was used to detect the mutation in the blood samples of the couple, their son, and 01 embryo that were biopsied on the fifth day based on the findings of next-generation sequencing (NGS) of the affected son. We combined Sanger sequencing and linkage analysis using short tandem repeats (STR) to provide diagnostic results. Results: We performed preimplantation genetic diagnosis for AIS on an embryo from a couple who had previously had an affected son. Consequently, one healthy embryo was diagnosed without the variant NM_000044: c.796del (p.Asp266IlefsTer30). Conclusion: We report on a novel variant (NM_000044: c.796del (p.Asp266IlefsTer30)) in the AR gene discovered in Vietnam. The developed protocol was helpful for the preimplantation genetic diagnosis process to help families with the monogenic disease of AIS but wish to have healthy children.

4.
bioRxiv ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38766054

RESUMEN

Identifying the causal variants and mechanisms that drive complex traits and diseases remains a core problem in human genetics. The majority of these variants have individually weak effects and lie in non-coding gene-regulatory elements where we lack a complete understanding of how single nucleotide alterations modulate transcriptional processes to affect human phenotypes. To address this, we measured the activity of 221,412 trait-associated variants that had been statistically fine-mapped using a Massively Parallel Reporter Assay (MPRA) in 5 diverse cell-types. We show that MPRA is able to discriminate between likely causal variants and controls, identifying 12,025 regulatory variants with high precision. Although the effects of these variants largely agree with orthogonal measures of function, only 69% can plausibly be explained by the disruption of a known transcription factor (TF) binding motif. We dissect the mechanisms of 136 variants using saturation mutagenesis and assign impacted TFs for 91% of variants without a clear canonical mechanism. Finally, we provide evidence that epistasis is prevalent for variants in close proximity and identify multiple functional variants on the same haplotype at a small, but important, subset of trait-associated loci. Overall, our study provides a systematic functional characterization of likely causal common variants underlying complex and molecular human traits, enabling new insights into the regulatory grammar underlying disease risk.

5.
Biochem Biophys Res Commun ; 719: 150043, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38735206

RESUMEN

In this study, a simple green synthesis of vanadium pentoxide nanoparticles (VNPs) was prepared by the extract of Kaffir lime fruit (Citrus hystrix) as a green reducing and stabilizing agent, along with the investigation of calcination temperature was carried out at 450 and 550 °C. It was affirmed that, at higher temperature (550 °C), the VNPs possessed a high degree crystalline following the construction of (001) lattice diffraction within an increase in crystalline size from 47.12 to 53.51 nm, although the band gap of the materials at 450 °C was lower than that of the VNPs-550 (2.53 versus 2.66 eV, respectively). Besides, the materials were assessed for the potential bioactivities toward antibacterial, antifungal, DNA cleavage, anti-inflammatory, and hemolytic performances. As a result, the antibacterial activity, with minimal inhalation concentration (MIC) < 6.25 µg/mL for both strains, and fungicidal one of the materials depicted the dose-dependent effects. Once, both VNPs exhibited the noticeable efficacy of the DNA microbial damage, meanwhile, the outstanding anti-inflammatory agent was involved with the IC50 of 123.636 and 227.706 µg/mL, accounting for VNPs-450 and VNPs-550, respectively. Furthermore, this study also demonstrated the hemolytic potential of the VNPs materials. These consequences declare the prospects of the VNPs as the smart and alternative material from the green procedure in biomedicine.

6.
RSC Adv ; 14(23): 16445-16458, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38774611

RESUMEN

Using DFT calculations, the structural and electronic properties of the ZZ7 p-PdSe2 nanoribbons (ZZ7) with the four kinds of vacancy defects, including ZZ7-VPd, ZZ7-VSe, ZZ7-VPd+Se, and ZZ7-V2Se are studied, in which their stability, diverse geometries, and altered electronic properties are determined through the formation energies, optimal structural parameters, electronic band structures, and DOSs. Specifically, the formation energies of all studied systems show significant negative values around -3.9 eV, evidencing their good thermal stability. The geometries of four defective structures exhibit different diversification, whereas only the ZZ7-V2Se structure possesses the highly enhanced feature, identified as the most effective substrate for the acetone and acetonitrile adsorption. On the electronic behaviors, the ZZ7 band structure displays the nonmagnetic metallic characteristics that become the ferromagnetic half-metallic band structures for the ZZ7-VPd and ZZ7-VSe and the ferromagnetic semi-metallic band structures for the ZZ7-VPd+Se and ZZ7-V2Se. For adsorption of the acetone and acetonitrile on the ZZ7-V2Se structure, the energetic stability, adsorption sites, adsorption distances, charge transfers, and electronic characteristics of the adsorbed systems are determined by the adsorption energies, optimal adsorption sites, adsorption distances, Mulliken populations, and DOSs. The adsorption energies of the acetone- and acetonitrile-adsorbed ZZ7-V2Se systems display significant values at -1.2 eV and -0.86 eV at the preferable sites of 8 and 11, respectively, indicating their great adsorption ability. The adsorption mechanism of the acetone- and acetonitrile-adsorbed systems belongs to the physisorption owing to absence of chemical bonds, in which the bond lengths of the ZZ7-V2Se substrate show a very small deviation. Under the acetone and acetonitrile adsorptions, the ferromagnetic semi-metallic DOSs of the ZZ7-V2Se become the ferromagnetic half-metallic DOSs for the ZZ7-V2Se-acetone-8 and the ferromagnetic semiconducting DOSs for the ZZ7-V2Se-acetonitrile-11. Our systematic results can provide a complete understanding of the acetone- and acetonitrile adsorptions on the potential ZZ7-V2Se structure, which is very useful for nanosensor application.

7.
Nat Prod Res ; : 1-7, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771007

RESUMEN

Phytochemical study of the leaves of Styrax annamensis Guillaumin resulted in the isolation of a new natural product egonol-3''-sulphate (1), and two new derivatives egonol-3-methyl-D-galactopyranoside (2) and 7-methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran-5-carboxamide (3). Their chemical structures were -elucidated by spectroscopic data. Compounds 1 and 3 significantly established a great role for the chemotaxonomic aspect. Compound 1 showed cytotoxicity against four cancer cell lines KB, HepG2, Lu, and MCF7 with the IC50 values of 84.90-101.69 µg/mL, and exhibited acetylcholinesterase (AChE) inhibitory activity with the IC50 value of 97.08 µg/mL.

8.
Environ Res ; 252(Pt 4): 119143, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38751000

RESUMEN

In this study, biochar derived from chestnut shells was synthesized through pyrolysis at varying temperatures from 300 °C to 900 °C. The study unveiled that the pyrolysis temperature is pivotal in defining the physical and chemical attributes of biochar, notably its adsorption capabilities and its role in activating peracetic acid (PAA) for the efficient removal of acetaminophen (APAP) from aquatic environments. Notably, the biochar processed at 900 °C, referred to as CN900, demonstrated an exceptional adsorption efficiency of 55.8 mg g-1, significantly outperforming its counterparts produced at lower temperatures (CN300, CN500, and CN700). This enhanced performance of CN900 is attributed to its increased surface area, improved micro-porosity, and a greater abundance of oxygen-containing functional groups, which are a consequence of the elevated pyrolysis temperature. These oxygen-rich functional groups, such as carbonyls, play a crucial role in facilitating the decomposition of the O-O bond in PAA, leading to the generation of reactive oxygen species (ROS) through electron transfer mechanisms. This investigation contributes to the development of sustainable and cost-effective materials for water purification, underscoring the potential of chestnut shell-derived biochar as an efficient adsorbent and catalyst for PAA activation, thereby offering a viable solution for environmental cleanup efforts.

9.
Stroke ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753954

RESUMEN

Background: Acute ischemic stroke (AIS) with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO-AIS is modified by initial stroke severity (baseline NIHSS) and arterial occlusion site. Methods: Based on the multicenter, retrospective, case-control study of consecutive iPCAO-AIS patients (PLATO study), we assessed the heterogeneity of EVT outcomes compared to medical management (MM) for iPCAO, according to baseline NIHSS (≤6 vs. >6) and occlusion site (P1 vs. P2), using multivariable regression modelling with interaction terms. The primary outcome was the favorable shift of 3-month mRS. Secondary outcomes included excellent outcome (mRS 0-1), functional independence (mRS 0-2), symptomatic intracranial hemorrhage (sICH) and mortality. Results: From 1344 patients assessed for eligibility, 1,059 were included (median age 74 years, 43.7% women, 41.3% had intravenous thrombolysis), 364 receiving EVT and 695 MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (pint=0.312), but did with functional independence (pint=0.010), with a similar trend on excellent outcome (pint=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS>6 (mRS 0-1: 30.6% vs. 17.7%, aOR=2.01, 95%CI=1.22-3.31; mRS 0-2: 46.1% vs. 31.9%, aOR=1.64, 95%CI=1.08-2.51), but not in those with NIHSS≤6 (mRS 0-1: 43.8% vs. 46.3%, aOR=0.90, 95%CI=0.49-1.64; mRS 0-2: 65.3% vs. 74.3%, aOR=0.55, 95%CI=0.30-1.0). EVT was associated with more sICH regardless of baseline NIHSS (pint=0.467), while the mortality increase was more pronounced in patients with NIHSS≤6 (pint=0.044, NIHSS≤6: aOR=7.95,95%CI=3.11-20.28, NIHSS>6: aOR=1.98,95%CI=1.08-3.65). Arterial occlusion site did not modify the association of EVT with outcomes compared to MM. Conclusion: Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS>6) had more favorable disability outcomes with EVT than MM, despite increased mortality and sICH.

10.
Phys Chem Chem Phys ; 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691388

RESUMEN

The diverse structural, electronic, and magnetic properties of silicon (Si)-substituted armchair and zigzag graphene nanoribbons (AGNRs and ZGNRs) were investigated using spin-polarized density functional theory (DFT) calculations. Pristine AGNRs belong to a nonmagnetic semiconductor with a direct bandgap of 1.63/1.92 eV determined by PBE/HSE06 functionals. Under various Si substitutions, nonmagnetic bandgaps were tuned at 1.49/1.87, 1.06/1.84, 0.81/1.45, 1.04/1.71, 0.89/1.05, and 2.38/3.0 eV (PBE/HSE06) in the single Si edge-, single Si non-edge-, double Si ortho-, double Si meta-, double Si para-, and 100% Si-substituted AGNR configurations, respectively. Meanwhile, pristine ZGNRs displayed antiferromagnetic semiconducting behavior with a spin degenerate bandgap of 0.52/0.81 eV (PBE/HSE06) and becomes a ferromagnetic semimetal in the single Si configurations or an unusual ferromagnetic semiconductor in the 100% Si configuration. Under the developed first-principles theoretical framework, the formation of quasi π (C-2pz and Si-3pz) and quasi σ (C-2s, -2pxy and Si-3s and -3pxy) bands was identified in the Si-substituted configurations. These quasi π and quasi σ bands showed weak separation, resulting in weak quasi sp2 hybridization in Si-C bonds, in which the identified hybridization mechanism was a strong evidence for the formation of stable planar 1D structures in the Si-substituted configurations. Our complete revelation of the essential properties of Si-substituted GNRs can provide a complete understanding of their chemically doped 1D materials for various practical applications.

11.
Artículo en Inglés | MEDLINE | ID: mdl-38697792

RESUMEN

BACKGROUND AND PURPOSE: Contrast staining is a common finding after endovascular treatment of acute ischemic stroke. It typically occurs in infarcted tissue and is considered an indicator of irreversible brain damage. Contrast staining in noninfarcted tissue has not been systematically investigated. We sought to assess the incidence, risk factors, and clinical significance of contrast staining in noninfarcted tissue after endovascular treatment. MATERIALS AND METHODS: We conducted a retrospective review of consecutive patients who underwent endovascular treatment for anterior circulation large-vessel occlusion acute ischemic stroke. Contrast staining, defined as new hyperdensity on CT after endovascular treatment, was categorized as either contrast staining in infarcted tissue if the stained region demonstrated restricted diffusion on follow-up MR imaging or contrast staining in noninfarcted tissue if the stained region demonstrated no restricted diffusion. Baseline differences between patients with and without contrast staining in noninfarcted tissue were compared. Logistic regression was used to identify independent associations for contrast staining in noninfarcted tissue after endovascular treatment. RESULTS: Among 194 patients who underwent endovascular treatment for large-vessel occlusion acute ischemic stroke and met the inclusion criteria, contrast staining in infarcted tissue was noted in 52/194 (26.8%) patients; contrast staining in noninfarcted tissue, in 26 (13.4%) patients. Both contrast staining in infarcted tissue and contrast staining in noninfarcted tissue were noted in 5.6% (11/194). Patients with contrast staining in noninfarcted tissue were found to have a higher likelihood of having an ASPECTS of 8-10, to be associated with contrast staining in infarcted tissue, and to achieve successful reperfusion compared with those without contrast staining in noninfarcted tissue. In contrast staining in noninfarcted tissue regions, the average attenuation was 40 HU, significantly lower than the contrast staining in infarcted tissue regions (53 HU). None of the patients with contrast staining in noninfarcted tissue had clinical worsening during their hospital stay. The median discharge mRS was significantly lower in patients with contrast staining in noninfarcted tissue than in those without (3 versus 4; P = .018). No independent predictors of contrast staining in noninfarcted tissue were found. CONCLUSIONS: Contrast staining can be seen outside the infarcted tissue after endovascular treatment of acute ischemic stroke, likely attributable to the reversible disruption of the BBB in ischemic but not infarcted tissue. While generally benign, understanding its characteristics is important because it may mimic pathologic conditions such as infarcted tissue and cerebral edema.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38697916

RESUMEN

Objective: This study validated the Vietnamese version of the Disaster Adaptation and Resilience Scale (DARS) for use in vulnerable communities in Vietnam. Methods: This was a cross-sectional study involving 595 adults from 2 identified communities. The original DARS assessment tool was translated, and the validity and reliability of the Vietnamese version of DARS (V-DARS) were assessed. The internal consistency of the overall scale and its subscales was evaluated using Cronbach's alpha and McDonald's omega reliability coefficients. Confirmatory factor analysis (CFA) was employed to evaluate its construct validity, building upon the factor structure identified in exploratory factor analysis (EFA). Construct validity was assessed based on convergent and discriminant validity. Results: Following the established criteria for EFA, 8 items were removed, resulting in a refined V-DARS structure comprising 35 items distributed across 5 distinct factors. Both alpha and omega reliability coefficients indicated strong internal consistency for the overall scale (α = .963, ω = .963) and for each of the 5 sub-scales (all > 0.80). The CFA model also retained the 5-factor structure with 35 items. The model fit indices showed acceptable values (RMSEA: 0.072; CFI: 0.912; TLI: 0.904; chi-square test: <0.01). Additionally, the convergent and discriminant validity of the V-DARS were deemed appropriate and satisfactory for explaining the measurement structure. Conclusions: Our findings suggest that the V-DARS is a valid and reliable scale for use within vulnerable communities in Vietnam to assess adaptive responses to natural disasters. It may also be considered for use in other populations.

13.
Chem Biodivers ; : e202400864, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38699953

RESUMEN

Pinostrobin demonstrated anticancer properties, but its hydrophobic feature led to a reduction in bioavailability. The mitochondria-targeted approach successfully synthesized eight new alkyl triphenylphosphonium pinostrobin derivatives (1-8) with good yield in this study. Seven compounds (1-3, 5-8) showed greater cytotoxic potency against the human MCF-7 breast cancer cell line than pinostrobin. Molecular docking studies were performed with two important targets in hormone-dependent anticancer strategies, estrogen receptor α (ERα) ligand binding domains, 3ERT (antagonist recognition and antiproliferative function), and 1GWR (agonist recognition and pro-proliferative function). In addition, the MD simulation study of the two most potent compounds (2 and 3) complexed with both ERα forms suggested that compounds 2 and 3 could serve as favourable antagonists. Furthermore, the in silico ADMET prediction indicated that compounds 2 and 3 could be potential drug candidates.

14.
Psychol Health Med ; : 1-18, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700271

RESUMEN

Antibiotic resistance (AR) rates in Vietnam are among the highest in Asia, and recent infections due to multi-drug resistance in the country have caused thousands of deaths each year. This study investigated a Vietnamese community's preferences for antibiotic treatment and its knowledge and attitudes regarding antibiotics. A discrete choice experiment-based survey was developed and administered to the population of interest. The respondents were given sociodemographic-, knowledge- and attitude-related items and 17 pairs of choice tasks. Two hypothetical options were included in each choice task. Latent class analysis was conducted to determine the differences among the respondents' preferences. Among 1,014 respondents, 805 (79.4%) gave valid questionnaires. A three-latent-class model with four covariates (age, healthcare-related education or career, occupation, and attitude classifications) was used in the analysis. All five attributes significantly influenced the respondents' decisions. The majority, including young employed respondents with non-healthcare-related work or education, found treatment failure more important. Older respondents who had healthcare-related education/careers and/or appropriate antibiotic use- and antibiotics resistance-related attitudes, regarded contribution to antibiotic resistance as an important attribute in selecting antibiotic treatments. Unemployed individuals with correct knowledge identified the cost of antibiotic treatment as the most essential decision-making factor. Findings suggest minimal antibiotic impact on resistance; only 7.83% view it as amajor concern. The respondents exhibited substantial preference heterogeneity, and the general Vietnamese public had poor knowledge of and attitudes toward antibiotic use and antibiotic resistance. This study emphasizes the need for individual responsibility for antibiotic resistance and appropriate antibiotic use.

15.
Neurology ; 102(10): e209324, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38709999

RESUMEN

BACKGROUND AND OBJECTIVES: There is uncertainty whether patients with large vessel occlusion (LVO) presenting in the late 6-hour to 24-hour time window can be selected for endovascular therapy (EVT) by noncontrast CT (NCCT) and CT angiography (CTA) for LVO detection. We evaluated the clinical outcomes of patients selected for EVT by NCCT compared with those medically managed in the extended time window. METHODS: This multinational cohort study was conducted at 66 sites across 10 countries. Consecutive patients with proximal anterior LVO stroke selected for EVT by NCCT or medically managed and presenting within 6-24 hours of time last seen well (TSLW) from January 2014 to May 2022 were included. The primary end point was the 90-day ordinal shift in the modified Rankin Scale (mRS) score. Inverse probability treatment weighting (IPTW) and multivariable methods were used. RESULTS: Of 5,098 patients screened, 839 patients were included, with a median (interquartile range) age of 75 (64-83) years; 455 (54.2%) were women. There were 616 patients selected to undergo EVT by NCCT (73.4%) and 223 (26.6%) who were medically managed. In IPTW analyses, there was a more favorable 90-day ordinal mRS shift in patients selected by NCCT to EVT vs those who were medically managed (odds ratio [OR] 1.99, 95% CI 1.53-2.59; p < 0.001). There were higher rates of 90-day functional independence (mRS 0-2) in the EVT group (40.1% vs 18.4%, OR 3.31, 95% CI 2.11-5.20; p < 0.001). sICH was nonsignificantly higher in the EVT group (8.5% vs 1.4%, OR 3.77, 95% CI 0.72-19.7, p = 0.12). Mortality at 90 days was lower in the EVT vs MM group (23.9% vs 32.3%, OR 0.61, 95% CI 0.45-0.83, p = 0.002). DISCUSSION: In patients with proximal anterior LVO in the extended time window, there was a lower rate of disability and mortality in patients selected with NCCT and CTA to EVT compared with those who were medically managed. These findings support the use of NCCT as a simpler and more inclusive approach to patient selection in the extended window. TRIAL REGISTRATION INFORMATION: This study was registered at ClinicalTrials.gov under NCT04096248. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with proximal anterior circulation occlusion presenting with ischemic stroke from 6 to 24 hours, compared with medical management, those undergoing thrombectomy based on NCCT have reduced disability and mortality at 90 days.


Asunto(s)
Procedimientos Endovasculares , Trombectomía , Humanos , Femenino , Anciano , Masculino , Trombectomía/métodos , Anciano de 80 o más Años , Persona de Mediana Edad , Procedimientos Endovasculares/métodos , Angiografía por Tomografía Computarizada , Tomografía Computarizada por Rayos X , Estudios de Cohortes , Tiempo de Tratamiento , Resultado del Tratamiento , Angiografía Cerebral
16.
Chem Sci ; 15(19): 7187-7197, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38756818

RESUMEN

The halolactonization reaction provides rapid access to densely functionalized lactones from unsaturated carboxylic acids. The endo/exo regioselectivity of this cyclization reaction is primarily determined by the electronic stabilization of alkene substituents, thus making it inherently dependent on substrate structures. Therefore this method often affords one type of halolactone regioisomer only. Herein, we introduce a simple and efficient method for regioselectivity-switchable bromolactonization reactions mediated by HFIP solvent. Two sets of reaction conditions were developed, each forming endo-products or exo-products in excellent regioselectivity. A combination of computational and experimental mechanistic studies not only confirmed the crucial role of HFIP, but also revealed the formation of endo-products under kinetic control and exo-products under thermodynamic control. This study paves the way for future work on the use of perfluorinated solvents to dictate reaction outcomes in organic synthesis.

17.
Ann Neurol ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38752428

RESUMEN

OBJECTIVE: We aimed to evaluate the association between rescue therapy (RT) and functional outcomes compared to medical management (MM) in patients presenting after failed mechanical thrombectomy (MT). METHODS: This cross-sectional study utilized prospectively collected and maintained data from the Society of Vascular and Interventional Neurology Registry, spanning from 2011 to 2021. The cohort comprised patients with large vessel occlusions (LVOs) with failed MT. The primary outcome was the shift in the degree of disability, as gauged by the modified Rankin Scale (mRS) at 90 days. Additional outcomes included functional independence (90-day mRS score of 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. RESULTS: Of a total of 7,018 patients, 958 presented failed MT and were included in the analysis. The RT group comprised 407 (42.4%) patients, and the MM group consisted of 551 (57.5%) patients. After adjusting for confounders, the RT group showed a favorable shift in the overall 90-day mRS distribution (adjusted common odds ratio = 1.79, 95% confidence interval [CI] = 1.32-2.45, p < 0.001) and higher rates of functional independence (RT: 28.8% vs MM: 15.7%, adjusted odds ratio [aOR] = 1.93, 95% CI = 1.21-3.07, p = 0.005) compared to the MM group. RT also showed lower rates of sICH (RT: 3.8% vs MM: 9.1%, aOR = 0.52, 95% CI = 0.28-0.97, p = 0.039) and 90-day mortality (RT: 33.4% vs MM: 45.5%, aOR = 0.61, 95% CI = 0.42-0.89, p = 0.009). INTERPRETATION: Our findings advocate for the utilization of RT as a potential treatment strategy for cases of LVO resistant to first-line MT techniques. Prospective studies are warranted to validate these observations and optimize the endovascular approach for failed MT patients. ANN NEUROL 2024.

18.
Neuroophthalmology ; 48(3): 193-197, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756336

RESUMEN

Ma Huang (Ephedra), a traditional herbal remedy, which contains pseudoephedrine and ephedrine, has sympathomimetic characteristics. Despite being banned by the Federal Drug Administration in 2004, it is still used for weight loss and energy boosting in some countries. A previous healthy 42-year-old woman experienced sudden blurred vision in both eyes. Her pupils were dilated to 6 mm each, showing diminished light reflex responses, and were not responsive to both 0.1% and 1% pilocarpine. The day before the onset of her symptoms she had taken a herbal supplement. The woman's herbal medicine was believed to contain ephedrine, a component found in Ma Huang. The sympathomimetic effects of this substance could potentially induce mydriasis. After discontinuing the medication, her symptoms improved over 4 days, leading to a suspicion of drug-induced bilateral mydriasis. Herbal products prescribed for weight loss, which may contain potential elements such as Ma Huang, could lead to unforeseen side effects like bilateral mydriasis, and should be appropriately highlighted.

19.
Proc Natl Acad Sci U S A ; 121(21): e2322923121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38739798

RESUMEN

The ubiquitin-proteasome system is essential to all eukaryotes and has been shown to be critical to parasite survival as well, including Plasmodium falciparum, the causative agent of the deadliest form of malarial disease. Despite the central role of the ubiquitin-proteasome pathway to parasite viability across its entire life-cycle, specific inhibitors targeting the individual enzymes mediating ubiquitin attachment and removal do not currently exist. The ability to disrupt P. falciparum growth at multiple developmental stages is particularly attractive as this could potentially prevent both disease pathology, caused by asexually dividing parasites, as well as transmission which is mediated by sexually differentiated parasites. The deubiquitinating enzyme PfUCHL3 is an essential protein, transcribed across both human and mosquito developmental stages. PfUCHL3 is considered hard to drug by conventional methods given the high level of homology of its active site to human UCHL3 as well as to other UCH domain enzymes. Here, we apply the RaPID mRNA display technology and identify constrained peptides capable of binding to PfUCHL3 with nanomolar affinities. The two lead peptides were found to selectively inhibit the deubiquitinase activity of PfUCHL3 versus HsUCHL3. NMR spectroscopy revealed that the peptides do not act by binding to the active site but instead block binding of the ubiquitin substrate. We demonstrate that this approach can be used to target essential protein-protein interactions within the Plasmodium ubiquitin pathway, enabling the application of chemically constrained peptides as a novel class of antimalarial therapeutics.


Asunto(s)
Péptidos , Plasmodium falciparum , Proteínas Protozoarias , Ubiquitina Tiolesterasa , Plasmodium falciparum/enzimología , Plasmodium falciparum/metabolismo , Plasmodium falciparum/efectos de los fármacos , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Ubiquitina Tiolesterasa/genética , Humanos , Péptidos/química , Péptidos/metabolismo , Péptidos/farmacología , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Proteínas Protozoarias/antagonistas & inhibidores , Antimaláricos/farmacología , Antimaláricos/química , Ubiquitina/metabolismo , Malaria Falciparum/parasitología , Malaria Falciparum/tratamiento farmacológico
20.
Eur Stroke J ; : 23969873241249295, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38726983

RESUMEN

BACKGROUND: Stroke remains a major health concern globally, with oral anticoagulants widely prescribed for stroke prevention. The efficacy and safety of mechanical thrombectomy (MT) in anticoagulated patients with distal medium vessel occlusions (DMVO) are not well understood. METHODS: This retrospective analysis involved 1282 acute ischemic stroke (AIS) patients who underwent MT in 37 centers across North America, Asia, and Europe from September 2017 to July 2023. Data on demographics, clinical presentation, treatment specifics, and outcomes were collected. The primary outcomes were functional outcomes at 90 days post-MT, measured by modified Rankin Scale (mRS) scores. Secondary outcomes included reperfusion rates, mortality, and hemorrhagic complications. RESULTS: Of the patients, 223 (34%) were on anticoagulation therapy. Anticoagulated patients were older (median age 78 vs 74 years; p < 0.001) and had a higher prevalence of atrial fibrillation (77% vs 26%; p < 0.001). Their baseline National Institutes of Health Stroke Scale (NIHSS) scores were also higher (median 12 vs 9; p = 0.002). Before propensity score matching (PSM), anticoagulated patients had similar rates of favorable 90-day outcomes (mRS 0-1: 30% vs 37%, p = 0.1; mRS 0-2: 47% vs 50%, p = 0.41) but higher mortality (26% vs 17%, p = 0.008). After PSM, there were no significant differences in outcomes between the two groups. CONCLUSION: Anticoagulated patients undergoing MT for AIS due to DMVO did not show significant differences in 90-day mRS outcomes, reperfusion, or hemorrhage compared to non-anticoagulated patients after adjustment for covariates.

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