Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Pediatr Hematol Oncol ; 46(5): 272-274, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38857164

RESUMO

APML, a subtype of acute myeloid leukemia, is highly curable, with cure rates over 90%. Despite its therapeutic success, APML poses elevated bleeding risks due to frequent prior disseminated intravascular coagulation. Less commonly recognized but critical is the thrombotic risk. We document a unique pediatric case: a 13-year-old with trisomy 21 diagnosed with APML had an asymptomatic aortic valve thrombus leading to thromboembolic arterial ischemic stroke. Through endovascular thrombectomy, cerebral circulation was re-established, extracting a fibrin thrombus with APML cells. Neurological recovery was swift. This report underscores the importance of vigilance for thrombotic complications in APML, highlighting the potential severity of overlooked risks.


Assuntos
Síndrome de Down , Trombectomia , Trombose , Humanos , Síndrome de Down/complicações , Adolescente , Trombectomia/métodos , Trombose/etiologia , Trombose/patologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Valva Aórtica/cirurgia , Valva Aórtica/patologia , Masculino , Procedimentos Endovasculares/métodos , Feminino
2.
RSC Adv ; 14(19): 13286-13290, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38655473

RESUMO

Cucurbiturils (CBn) are known to establish stable host-guest complexes with a variety of drug molecules. Herein, the supramolecular complexation between cucurbit[7]uril (CB7) and phenylephrine hydrochloride is reported in aqueous solution. Phenylephrine forms inclusion complex with CB7 with high binding affinity (Kaffinity = 4.0 × 106 M-1), which allows for the development of a fluorescence-based sensing assay applying the dye displacement strategy. The structure of the host-guest inclusion complex is investigated by 1H NMR spectroscopy, in which complexation-induced chemical shifts indicate the immersion of the aromatic ring inside the hydrophobic cavity of CB7. Density functional theory (DFT) calculations support the 1H NMR results, and reveal that the complex is stabilized through intermolecular interactions between the polar groups on the phenylephrine and the carbonyl rims of CB7, as well as the hydrophobic effect. Moreover, preferential binding of phenylephrine in its protonated over the neutral form results in a complexation-induced pKa shift.

4.
Chem Commun (Camb) ; 58(14): 2363-2366, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35080530

RESUMO

A new set of hybrid guest molecules bearing organic and inorganic residues have been studied for their recognition by cyclodextrins in aqueous solution. The guest molecules consist of nitroanilines linked through their amino group to the dodecahydrido-closo-dodecaborate cluster B12H122-, which serves as an anchor group. They show sizable affinity to cyclodextrins, and unexpected photophysical properties, with a very strong and low-energy charge-transfer band. The dodecaborate cluster increases the pKa of the anilines by 5.0 to 5.7 pH units, and the deprotonated forms of the o- and p-nitroaniline derivatives show strong charge transfer absorption bands in the visible part of the spectrum.

5.
Org Biomol Chem ; 19(39): 8521-8529, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34378628

RESUMO

The accurate determination of ultra-high binding affinities in supramolecular host-guest chemistry is a challenging endeavour because direct binding titrations are generally limited to affinities <106 M-1 due to sensitivity constraints of common titration methods. To determine higher affinities, competitive titrations are usually performed, in which one compound with a well established binding affinity serves as a reference. Herein, we propose a reference scale for such competitive titrations with the host cucurbit[7]uril (CB7) comprising binding affinities in the range from 103 to 1015 M-1. The suggested reference compounds are commercially available and will aid in the future determination of CB7 binding affinities for stimuli-responsive host-guest systems.

6.
Case Rep Oncol ; 14(1): 585-591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33976638

RESUMO

Neuroblastoma is the most common cancer in infants younger than 12 months of age, occurring with an incidence of 1 in 100,000 children. The clinical outcome of neuroblastoma ranges from spontaneous regression to treatment-resistant progression and/or metastasis, and accounts for 8-10% of childhood cancer deaths. Segmental chromosomal aberrations, as well as MYCN and ALK amplification, are among factors contributing to an unfavorable genomic profile and high-risk disease classification. Here, we describe a 5-year-old male who presented with a large right renal neuroblastoma tumor having lung and liver metastases. Fluorescence in situ hybridization analysis indicated the presence of >20 copies of the 5' region of the ALK gene in 26% of cells examined. Subsequent copy number assessment did not confirm ALK amplification, but revealed a gain of exons 2-5 of ALK, consistent with increased copy number for the 5' region of the ALK gene. Subsequent array analysis showed the presence of other unfavorable prognostic genomic features, including segmental gain of the 17q region and amplification of the long arm of chromosome 12 harboring CDK4 and MDM2, both reported to be poor prognostic indicators in patients with atypical clinical features in neuroblastoma. Taken together, this report illustrates the importance of careful interpretation of aberrant FISH findings and subsequent use of orthogonal methods to clarify the presence of genomic alterations to successfully determine potential treatment targets.

7.
Org Biomol Chem ; 18(11): 2120-2128, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32129437

RESUMO

Cucurbit[n]urils (CBn, n = 6-8) serve as molecular receptors for imidazolium-based ionic liquids (ILs) in aqueous solution. The amphiphilic nature of 1-alkyl-3-methylimidazolium guests (Cnmim), with a cationic imidazolium residue and a hydrophobic alkyl chain, enabled their complexation with CBn through a combination of the hydrophobic effect and ion-dipole interactions. 1H NMR experiments revealed that the cavity of CBn can host the hydrophobic chain of the ILs, while one of the carbonyl rims served as a docking site for the imidazolium ring. The structure of the complexes was further analyzed by molecular dynamics (MD) simulations, which indicated that the cavity of CB6 can accommodate up to 5 carbon atoms, while the larger cavity of CB7 and CB8 can encapsulate longer alkyl chains in folded conformations. Isothermal titration calorimetry (ITC) experiments provided up to micromolar affinity of ILs to CBn in aqueous solution, which was independently quantified by indicator displacement titrations.

8.
J Patient Exp ; 7(1): 116-123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32128380

RESUMO

OBJECTIVES: To describe patient-reported experience in a pediatric emergency department (ED) and determine: (1) whether there are differences between the experience children report in comparison to their parents; and (2) whether factors such as time of visit (day, evening, night) and ED census are associated with patient experience. METHODS: We conducted a prospective cross-sectional survey of children ≥8 years of age and the parents/guardians of children 0 to 17 years who visited a pediatric ED using a validated patient experience measure. The proportion of respondents for each question indicating that an aspect of their care could have been improved was calculated as problem scores for each survey item. The primary outcome was the overall problem scores for all respondents combined and for children and parents separately. RESULTS: A total of 237 parents and 109 children completed surveys. The areas with the highest problem scores identified by both parents and children were: having enough to do while waiting to be seen (53.5; 95% confidence interval [CI]: 48.1, 58.8) and when to restart usual activities (34.7; 95% CI: 29.7, 40.0). There were meaningful differences in problem scores between children and parents including: doctors and nurses explaining what they were doing (parents: 19; 95% CI: 14.3, 24.7, child 40.4; 95% CI: 31.2, 50.2) and privacy when examined and treated (parents: 17.3; 95% CI: 12.8, 22.9, child: 36.7; 95% CI: 27.8, 46.5). CONCLUSION: There are differences in reported experience between children and their parents. This highlights the importance of including children when assessing patient experience in a pediatric setting.

9.
Analyst ; 144(2): 579-586, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30427332

RESUMO

We report herein two methods to characterize the surface of mixed-ligand shell gold nanoparticles, which was explored with gold nanoparticles containing varying molar ratios of 3-mercaptopropionic acid (MPA) and 3-mercapto-1-propanesulfonate (MPS) or 11-mercaptoundecanoic acid (MUA) and triethylene glycol mono-11-mercaptoundecyl ether (TEG) in their ligand shell. Incubation of gold nanoparticles with a solution containing the transition metal cation Ni2+ allows the extraction of Ni2+ depending on the number of negatively charged surface groups and the reaction of surface carboxylic acid groups with an aminomethyladamantane derivative allows the extraction of the supramolecular host molecule cucurbit[7]uril (CB7) depending on the number of reactive surface groups. In both the methods, the remaining surface probes in the supernatant could be conveniently quantified in a homogeneous solution after a simple centrifugation step. An excellent linear correlation between the amount of Ni2+ extracted and the ligand density of MPA and MPS in MPA/MPS gold nanoparticles or MUA in MUA/TEG gold nanoparticles afforded a simple and reliable assay method to determine the number of negatively charged surface groups. The supramolecular CB7 assay enabled the determination of the accessible ligand density of reactive surface carboxylic acid groups and revealed a striking difference in the number of surface groups that can be reacted with MPA/MPS gold nanoparticles or MUA/TEG gold nanoparticles, which suggests a simple method to probe the surface structure of mixed monolayer gold nanoparticles.

10.
Beilstein J Org Chem ; 14: 1961-1971, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30202450

RESUMO

We introduce herein boron-dipyrromethene (BODIPY) dyes as a new class of fluorophores for the design of reporter dyes for supramolecular host-guest complex formation with cucurbit[7]uril (CB7). The BODIPYs contain a protonatable aniline nitrogen in the meso-position of the BODIPY chromophore, which was functionalized with known binding motifs for CB7. The unprotonated dyes show low fluorescence due to photoinduced electron transfer (PET), whereas the protonated dyes are highly fluorescent. Encapsulation of the binding motif inside CB7 positions the aniline nitrogen at the carbonyl rim of CB7, which affects the pKa value, and leads to a host-induced protonation and thus to a fluorescence increase. The possibility to tune binding affinities and pKa values is demonstrated and it is shown that, in combination with the beneficial photophysical properties of BODIPYs, several new applications of host-dye reporter pairs can be implemented. This includes indicator displacement assays with favourable absorption and emission wavelengths in the visible spectral region, fluorescence correlation spectroscopy, and noncovalent surface functionalization with fluorophores.

11.
Chem Commun (Camb) ; 54(14): 1734-1737, 2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29376528

RESUMO

We report the formation of supramolecular complexation between cucurbit[n]urils (CBn) and an amphiphilic pyridinium-functionalized anthracene (AnPy) in aqueous solution. The CB7 cavity is capable of accommodating the pyridinium moiety, while CB8 can encapsulate the pyridinium and anthracene moieties at once. The encapsulation of AnPy by CB7 leads to the formation of nanoparticles, while the complexation of AnPy with CB8 leads to the formation of nanorods.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...