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1.
Am J Obstet Gynecol ; 230(3): 356.e1-356.e10, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37741531

RESUMO

BACKGROUND: Prenatal diagnosis of cleft palate is challenging. Numerous 2-dimensional and 3-dimensional methods have been proposed to assess the integrity of the fetal palate, yet detection rates remain relatively low. We propose the "Hard Palate Sweep," a novel 2-dimensional method that enables clear demonstration of the entire fetal palate throughout pregnancy, in a single sweep, avoiding acoustic shadows cast by surrounding bones. OBJECTIVE: This study aimed to assess the feasibility and performance of the Hard Palate Sweep, performed throughout pregnancy. STUDY DESIGN: This was a prospective cross-sectional study performed between 2018 and 2022 in pregnant patients referred for a routine or targeted anomaly scan between 13 and 40 weeks of gestation. The presence or absence of a cleft palate was determined using the "Hard Palate Sweep." This was compared with the postnatal palate integrity assessment. Test feasibility and performance indices, including sensitivity, specificity, and positive and negative predictive values were calculated. Offline clips were reviewed by 2 investigators for the assessment of inter- and intraoperator agreement, using Cohen's kappa formula. The study protocol was approved by the institutional ethics committee. All participating patients were informed and provided consent. RESULTS: A total of 676 fetuses were included in the study. The Hard Palate Sweep was successfully performed in all cases, and 19 cases were determined to have a cleft palate. Of these, 13 cases were excluded because postmortem confirmation was not performed, leaving 663 cases available for analysis. Six cases determined to have a cleft palate were confirmed postnatally. In 655 of 657 cases prenatally determined to have an intact palate, this was confirmed postnatally. In the 2 remaining cases, rare forms of cleft palate were diagnosed postnatally, rendering 75% sensitivity, 100% specificity, 100% positive predictive value, and 99.7% negative predictive value for the Hard Palate Sweep (P<.001). There was complete intra- and interoperator agreement (kappa=1; P<.0001). CONCLUSION: The Hard Palate Sweep is a feasible and accurate method for prenatally detecting a cleft palate. It was successfully performed in all attempted cases between 13 and 40 weeks of gestation. This method is reproducible, offering high sensitivity and specificity. Implemented routinely, the Hard Palate Sweep is expected to increase the prenatal detection of cleft palate.


Assuntos
Fenda Labial , Fissura Palatina , Gravidez , Feminino , Humanos , Fissura Palatina/diagnóstico por imagem , Palato Duro/diagnóstico por imagem , Fenda Labial/diagnóstico por imagem , Estudos Prospectivos , Estudos Transversais , Ultrassonografia Pré-Natal/métodos
2.
J Am Chem Soc ; 128(49): 15697-700, 2006 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-17147379

RESUMO

A cross-linked polyethyleneimine polymer containing the [ZnWZn2(H2O)2(ZnW9O34)2]12- polyoxometalate was prepared from branched polyethyleneimine (Mw = 600), the polyoxometalate, and a n-octylamine-epichlorohydrin cross-linking reagent. This catalytic assembly was active for the selective oxidation of 2-alkanols to 2-alkanones with aqueous H2O2 with reactions presumably occurring at a hydrophobic domain. Most importantly, the catalyst showed distinctive lipophiloselectivity, that is selectivity as a function of the lipophilic nature of a reaction substrate. The lipophiloselectivity was proportional to the relative partition coefficient (1-octanol/water) of the substrates.

3.
Org Lett ; 8(24): 5445-8, 2006 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-17107043

RESUMO

Palladium nanoparticles were prepared, stabilized, and dispersed in water by alkylated branched polyethyleneimine. The palladium nanoparticles were effective aqueous biphasic catalysts for the chemoselective hydrogenation of alkenes with preferential reduction of less hindered double bonds, such as reduction of 3-methylcyclohexene in the presence of 1-methylcyclohexene and 1-octene in the presence of 2-methyl-2-heptene. [structure: see text].

4.
J Am Chem Soc ; 126(38): 11762-3, 2004 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-15382889

RESUMO

Combinations of alkylated polyethylenimine and polyoxometalates yield water-soluble synzymes with hydrophobic regions that allowed the aqueous biphasic selective oxidation of very hydrophobic, water-insoluble substrates with hydrogen peroxide. With the alkylated PEI/{PO4[WO(O2)2]4}3- highly effective C-C bond cleavage of alkenes to aldheydes was observed. The synzymes have both tertiary and quaternary amine centers as shown by a combination of 15N-1H HMBC and XPS measurements. The existence of hydrophobic regions was concluded from the measurement of contact angles and a hypsochromic shift of a fluorescent probe.

5.
Chem Commun (Camb) ; (8): 876-7, 2002 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-12123023

RESUMO

The H5PV2Mo10O40 polyoxometalate in a polyethylene glycol solvent was effective for a series of aerobic oxidation reactions including oxydehydrogenation of alcohols and cyclic dienes, oxidation of sulfides and the Wacker reaction; the solvent-catalyst phase can be recovered and recycled.


Assuntos
Polietilenoglicóis/química , Tensoativos/química , Compostos de Tungstênio/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Oxirredução , Solventes , Temperatura
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