Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Chem Pharm Bull (Tokyo) ; 72(5): 487-497, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38777760

RESUMEN

Herein, we report the functionalization of polyhedral oligosilsesquioxanes (POSS) and related siloxanes with arynes. Using o-triazenylarylboronic acids as aryne precursors and silica gel as the activator, the transformation of siloxane bearing various arynophilic moieties on the side chains was achieved with high yields without touching the siloxane core. This method was applied to the conjugation of POSS and pharmaceutical cores using an aryne derived from the synthetic intermediate of cabozantinib. Furthermore, orthogonal dual functionalization of POSS was realized by combining the aryne reaction with Huisgen cyclization.


Asunto(s)
Alquinos , Ácidos Borónicos , Siloxanos , Alquinos/química , Ácidos Borónicos/química , Ciclización , Estructura Molecular , Compuestos de Organosilicio/química , Compuestos de Organosilicio/síntesis química , Siloxanos/química , Triazinas/química
2.
J Assist Reprod Genet ; 39(9): 2089-2099, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35881272

RESUMEN

PROPOSE: Does an annotation-free embryo scoring system based on deep learning and time-lapse sequence images correlate with live birth (LB) and neonatal outcomes? METHODS: Patients who underwent SVBT cycles (3010 cycles, mean age: 39.3 ± 4.0). Scores were calculated using the iDAScore software module in the Vitrolife Technology Hub (Vitrolife, Gothenburg, Sweden). The correlation between iDAScore, LB rates, and total miscarriage (TM), including 1st- and 2nd-trimester miscarriage, was analysed using a trend test and multivariable logistic regression analysis. Furthermore, the correlation between the iDAScore and neonatal outcomes was analysed. RESULTS: LB rates decreased as iDAScore decreased (P < 0.05), and a similar inverse trend was observed for the TM rates. Additionally, multivariate logistic regression analysis showed that iDAScore significantly correlated with increased LB (adjusted odds ratio: 1.811, 95% CI: 1.666-1.976, P < 0.05) and decreased TM (adjusted odds ratio: 0.799, 95% CI: 0.706-0.905, P < 0.05). There was no significant correlation between iDAScore and neonatal outcomes, including congenital malformations, sex, gestational age, and birth weight. Multivariate logistic regression analysis, which included maternal and paternal age, maternal body mass index, parity, smoking, and presence or absence of caesarean section as confounding factors, revealed no significant difference in any neonatal characteristics. CONCLUSION: Automatic embryo scoring using iDAScore correlates with decreased miscarriage and increased LB and has no correlation with neonatal outcomes.


Asunto(s)
Aborto Espontáneo , Aprendizaje Profundo , Aborto Espontáneo/etiología , Adulto , Blastocisto , Cesárea , Criopreservación/métodos , Transferencia de Embrión/métodos , Femenino , Humanos , Recién Nacido , Nacimiento Vivo , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Transferencia de un Solo Embrión/métodos , Vitrificación
3.
Chem Pharm Bull (Tokyo) ; 70(8): 566-572, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35598985

RESUMEN

We report aryne generation from 2-triazenylarylboronic acids using an activator such as Brønsted acids, Lewis acids, and solid acids. With the use of (±)-Camphorsulfonic acid [(±)-CSA], the aryne precursors provided cycloadducts with a range of arynophiles in high yields. Aryne generated under the acidic conditions underwent chemoselective cycloaddition with a furan in the presence of a basic arynophile, namely an amine. Hammett plot analyses revealed that an aryne generation mechanism induced by (±)-CSA is distinct from the mechanism induced by silica gel.


Asunto(s)
Aminas , Ácidos de Lewis , Reacción de Cicloadición
4.
Reprod Biol Endocrinol ; 19(1): 98, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34215265

RESUMEN

BACKGROUND: The KIDScore™ Day 5 (KS-D5) model, version 3, is a general morphokinetic prediction model (Vitrolife, Sweden) for fetal heartbeat prediction after embryo transfer that was developed based on a large data set that included implantation results from a range of clinics with different patient populations, culture conditions and clinical practices. However, there was no study to comparing their pregnancy and live birth prediction ability among different maternal age. The aim of this study is to analyze the performance of KS-D5 in predicting pregnancy and live birth in various maternal age groups after single vitrified-warmed blastocyst transfer (SVBT). METHODS: A total of 2486 single vitrified-warmed blastocyst transfer (SVBT) cycles were analyzed retrospectively. Confirmed fetal heartbeat positive (FHB+) and live birth (LB+) rates were stratified by Society for Assisted Reproductive Technology (SART) maternal age criteria (< 35, 35-37, 38-40, 41-42 and ≥ 43 years of age). Within each age group, the performance of the prediction model was calculated using the AUC, and the results were compared across the age groups. RESULTS: In all age groups, the FHB+ rates decreased as the KIDScore decreased (P <  0.05). Conversely, the AUCs increased as the maternal age increased. The AUC of the < 35 age group (0.589) was significantly lower than the AUCs of the 41-42 age group (0.673) and the ≥43 age group (0.737), respectively (P <  0.05). In all age groups, the LB+ rates decreased as the KIDScore decreased (P <  0.05). Conversely, the AUCs increased as the maternal age increased. The AUC of the ≥43 age group (0.768) was significantly higher than the AUCs of other age groups (P <  0.05; < 35 age group = 0.596, 35-37 age group = 0.640, 38-40 age group = 0.646, 41-42 age group = 0.679). CONCLUSIONS: In the present study, we determined that the KIDScore model worked well for prediction of pregnancy and live birth outcomes in advanced age patients.


Asunto(s)
Transferencia de Embrión/métodos , Frecuencia Cardíaca Fetal/fisiología , Calor/uso terapéutico , Nacimiento Vivo/epidemiología , Edad Materna , Vitrificación , Adulto , Estudios de Cohortes , Transferencia de Embrión/tendencias , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos , Suecia/epidemiología
5.
Molecules ; 27(1)2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-35011332

RESUMEN

Propellanes are polycyclic compounds in which tricyclic systems share one carbon-carbon single bond. Propellane frameworks that consist of larger sized rings are found in a variety of natural products. As an approach to the stereoselective synthesis of the propellane framework, one of the efficient methods is forming several rings in a single operation. Lapidilectine B (1) is composed of a propellane framework and was synthesized through the oxidative cyclization of trisubstituted alkenes. When the alkene with an ester moiety was treated with N-iodosuccinimide (NIS), iodocyclization proceeded to give the cyclic carbamate. On the other hand, when PhI(OAc)2 was allowed to react in the carboxyl form, a furoindolin-2-one structure corresponding to the A-B-C ring of lapidilectine B (1) was produced. Furthermore, when Pd(OAc)2 catalyst was used for cyclization under oxidative conditions, the product yield was improved.

6.
Anal Chem ; 91(7): 4821-4830, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30869867

RESUMEN

Glucose is the most important energy source for living animals. Here, we developed a series of single fluorescent protein (FP)-based glucose indicators, named as "Green Glifons", to understand the hierarchal and mutual relationships between molecules involved in energy metabolism. Three indicators showed a different EC50 for glucose (50, 600, and 4000 µM), producing a ∼7-fold change in fluorescence intensity in response to glucose. The indicators could visualize glucose dynamics in the cytoplasm, plasma membrane, nucleus and mitochondria of living HeLa cells and in vivo, in the pharyngeal muscle of C. elegans and could measure murine blood glucose levels. Finally, the indicators were applicable to dual-color imaging, revealing the dynamic interplay between glucose and Ca2+ in mouse pancreatic MIN6 m9 ß cells. We propose that these indicators will facilitate and contribute to in vivo and multicolor imaging of energy metabolism.


Asunto(s)
Colorantes Fluorescentes/química , Glucosa/metabolismo , Proteínas Fluorescentes Verdes/química , Animales , Caenorhabditis elegans/química , Caenorhabditis elegans/metabolismo , Glucosa/análisis , Células HeLa , Humanos , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Imagen Óptica , Células Tumorales Cultivadas
7.
Org Biomol Chem ; 16(38): 6876-6881, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30229789

RESUMEN

Dirhodium(ii)-catalyzed ortho C-H amination of N,N-dialkylanilines has been developed. Sterically congested 1,2-diaminobenzenes were obtained in high yields with excellent chemo- and regioselectivities from para-substituted anilines and even from para-unsubstituted anilines. The ortho selectivity observed was rationalized in terms of the interaction between the dialkylamino group and a Rh(ii)-nitrene intermediate.

9.
J Am Chem Soc ; 135(38): 14078-81, 2013 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-24028674

RESUMEN

The hypervalent iodine-mediated C-C selective coupling of N-methanesulfonyl anilides with aromatic hydrocarbons has been developed. The first organocatalytic oxidative cross-biaryl-coupling was achieved by the catalyst control in defining specific 2,2'-diiodobiphenyls for the direct C-C bond formations.

10.
Org Lett ; 25(20): 3766-3771, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37167562

RESUMEN

Alkyldiarylsulfonium salts were synthesized by a combination of active sulfonium species, prepared through the activation of diarylsulfoxide, and alkyl nucleophiles. The isolated sulfonium salts were subjected to the allylation and cyclopropanation of the active methylene compounds and metal-free C(sp3)-C(sp2) couplings via oxyallyl cation intermediates under mild conditions. The series of reactions included an umpolung strategy for the coupling of alkyl nucleophiles and metal-free C-C bond formation using sulfonium salts.

11.
Chem Commun (Camb) ; 59(96): 14249-14252, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37947053

RESUMEN

Herein, a novel aryne species, 3-triazenylaryne, was developed and its regioselectivity was revealed. Based on the regioselectivity, various alkyne moieties were introduced by iodoalkynylation, and further derivatization to o-triazenylarylboronic acids as 3-alkynylaryne precursors was enabled. Therefore, 3-triazenylaryne was developed as a divergent platform for the generation of various 3-alkynylarynes.

12.
Chem Pharm Bull (Tokyo) ; 60(11): 1442-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23124568

RESUMEN

By utilizing a specific solvent and highly active 2-azaadamantane-N-oxyl (AZADO) as an organocatalyst, we have improved the recycling protocol of the adamatane reagent 1 to be faster and more operationally simple for the hypervalent iodine/nitroxyl radical mediated alcohol oxidation. This very mild system can efficiently mediate the oxidation of a range of alcohols to carbonyl compounds with a broad substrate scope, and after the reactions, the reduced adamantane tetraiodide 1', which automatically precipitated from the reaction mixtures as the reactions progresses, could be directly recovered by filtration.


Asunto(s)
Adamantano/análogos & derivados , Alcoholes/química , Óxidos N-Cíclicos/química , Yodo/química , Óxidos de Nitrógeno/química , Adamantano/química , Catálisis , Indicadores y Reactivos/química , Oxidación-Reducción
13.
Angew Chem Int Ed Engl ; 51(50): 12555-8, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23139190

RESUMEN

Dormant boron awaits its true destiny in diaryliodonium salts synthesized from aryl boronate derivatives according to two alternative general methods with hypervalent iodine(III) reagents and fluoroalcohol solvents: transformation of an aryl C-H bond and boron-iodine(III) exchange (see scheme; FG = functional group). The salts could be functionalized by both catalyst-free and metal-catalyzed reactions without loss of the boron functionality.


Asunto(s)
Boro/química , Ácidos Borónicos/química , Yodo/química , Compuestos Onio/química , Compuestos Onio/síntesis química , Sales (Química)/química
14.
Cell Chem Biol ; 29(1): 98-108.e4, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34197723

RESUMEN

Glucose is the main source of energy for organisms, and it is important to understand the spatiotemporal dynamics of intracellular glucose. Single fluorescent protein-based glucose indicators, named "Red Glifons" have been developed that apply to live-cell and dual-color imaging. These indicators exhibited more than 3-fold increase in fluorescence intensity in the presence of 10 mM glucose. The two Red Glifons developed have different half-maximal effective concentration (EC50) values for glucose (300 µM and 3,000 µM) and are able to monitor a wide range of glucose dynamics. Red Glifon combined with green indicators allowing visualization of the interplay between glucose and ATP, lactate, or pyruvate. Glucose influx in the pharyngeal muscle of Caenorhabditis elegans, enteroendocrine cells, and human iPS cell-derived cardiac myocytes was observed using the Red Glifons. Thus these red glucose indicators serve as a multi-color imaging toolkit for investigating complex interactions in energy metabolism.


Asunto(s)
Técnicas Biosensibles , Caenorhabditis elegans/metabolismo , Glucosa/análisis , Proteínas Luminiscentes/química , Animales , Caenorhabditis elegans/citología , Glucosa/metabolismo , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Ratones , Modelos Moleculares
15.
J Sports Sci ; 29(9): 919-26, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21574096

RESUMEN

We hypothesised that the oxygen supply to the fatigued muscles is improved after the recovery with exercise caused by aerobic metabolism in the slow twitch fibres during the recovery period. Ten males performed a 30 s maximum cycling (1st Exercise), followed by a 20 min rest interval (Interval Rest) in which participants were either sitting (No Exercise) or low intensive cycling (Active). Then they again underwent a 30 s bout of maximum cycling (2nd Exercise). The total work of the 2nd Exercise was higher in Active compared to No Exercise (297 ± 14 vs 276 ± 23 J · kg(-1), P < 0.01). After Interval Rest, the muscle oxygenation level (P < 0.05) and blood lactate concentration (P < 0.05) were lower in Active compared to No Exercise. In Active, the total work was higher in the 2nd Exercise than the 1st Exercise (297 ± 14 vs 277 ± 23 J · kg(-1), P < 0.01), and muscle oxygenation levels during the 2nd Exercise were also higher at 10 (P < 0.05) and 15 (P < 0.01) s after the beginning of the exercise. It was suggested that active recovery exercise would manage to increase the muscle oxygenation level, and improve the performance during the 2nd Exercise accompanied with blood lactate control.


Asunto(s)
Ciclismo/fisiología , Ejercicio Físico/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/metabolismo , Consumo de Oxígeno , Oxígeno/metabolismo , Descanso/fisiología , Adulto , Prueba de Esfuerzo , Humanos , Ácido Láctico/sangre , Masculino , Fibras Musculares de Contracción Lenta/metabolismo , Adulto Joven
16.
Reprod Sci ; 28(8): 2301-2309, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33751461

RESUMEN

This study aimed to compare the clinical outcomes of an oxidative stress-reducing embryo culture system (ORES) containing compounds that minimize intercellular oxidative stress, with those of a standard embryo culture system (StES). Furthermore, we investigated the efficiency of the ORES regarding the type of incubator used (time-lapse incubator [TLI] or non-time-lapse dry incubator [non-TLI]) and maternal age. In this retrospective study, we analyzed 3610 oocyte retrieval cycles (in 2537 patients) and 1726 single vitrified-warmed blastocyst transfer (SVBT) cycles (in 1726 patients) performed in a single center between April 2018 and July 2019. Transfers of single vitrified-warmed blastocysts, confirmed by fetal heartbeat, were used to assess clinical outcomes. The clinical outcomes of ORES and StES were compared in both TLI and non-TLI. Groups were stratified according to maternal age (≤39 years old, young age group; ≥40 years old, advanced age group). A significant difference in ongoing pregnancy rates was observed between the ORES and StES groups when non-TLI was used (34.9 vs. 27.0%, respectively; p < 0.05), unlike when TLI was used. Furthermore, ongoing pregnancy rates were significantly higher in the ORES group (24.8%) than in the StES group (14.9%) in the advanced age group, unlike in the young age group when non-TLI was used. In conclusion, compared to StEs, the ORES during all in vitro fertilization procedures improved ongoing pregnancy rates in the advanced age group using the non-TLI.


Asunto(s)
Técnicas de Cultivo de Embriones/instrumentación , Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Incubadoras , Adulto , Técnicas de Cultivo de Embriones/métodos , Femenino , Humanos , Edad Materna , Recuperación del Oocito , Inducción de la Ovulación , Embarazo , Índice de Embarazo , Estudios Retrospectivos
17.
Fertil Steril ; 116(4): 1172-1180, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34246469

RESUMEN

OBJECTIVE: To analyze the performance of an annotation-free embryo scoring system on the basis of deep learning for pregnancy prediction after single vitrified blastocyst transfer (SVBT) compared with the performance of other blastocyst grading systems dependent on annotation or morphology scores. DESIGN: A single-center large cohort retrospective study from an independent validation test. SETTING: Infertility clinic. PATIENT(S): Patients who underwent SVBT cycles (3,018 cycles, mean ± SD patient age 39.3 ± 4.0 years). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The pregnancy prediction performances of each embryo scoring model were compared using the area under curve (AUC) for predicting the fetal heartbeat status for each maternal age group. RESULT(S): The AUCs of the <35 years age group (n = 389) for pregnancy prediction were 0.72 for iDAScore, 0.66 for KIDScore, and 0.64 for the Gardner criteria. The AUC of iDAScore was significantly greater than those of the other two models. For the 35-37 years age group (n = 514), the AUCs were 0.68, 0.68, and 0.65 for iDAScore, KIDScore, and the Gardner criteria, respectively, and were not significantly different. The AUCs of the 38-40 years age group (n = 796) were 0.67 for iDAScore, 0.65 for KIDScore, and 0.64 for the Gardner criteria, and there were no significant differences. The AUCs of the 41-42 years age group (n = 636) were 0.66, 0.66, and 0.63 for iDAScore, KIDScore, and the Gardner criteria, respectively, and there were no significant differences among the pregnancy prediction models. For the >42 years age group (n = 389), the AUCs were 0.76 for iDAScore, 0.75 for KIDScore, and 0.75 for the Gardner criteria, and there were no significant differences. Thus, iDAScore AUC was either the highest or equal to the highest AUC for all age groups, although a significant difference was observed only in the youngest age group. CONCLUSION(S): Our results showed that objective embryo assessment by a completely automatic and annotation-free model, iDAScore, performed as well as or even better than more traditional embryo assessment or annotation-dependent ranking tools. iDAScore could be an optimal pregnancy prediction model after SVBT, especially in young patients.


Asunto(s)
Blastocisto/patología , Criopreservación , Aprendizaje Profundo , Fertilización In Vitro , Frecuencia Cardíaca Fetal , Interpretación de Imagen Asistida por Computador , Infertilidad/terapia , Transferencia de un Solo Embrión , Imagen de Lapso de Tiempo , Adulto , Técnicas de Cultivo de Embriones , Implantación del Embrión , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Infertilidad/diagnóstico , Infertilidad/fisiopatología , Edad Materna , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Transferencia de un Solo Embrión/efectos adversos , Resultado del Tratamiento , Vitrificación
18.
J Vet Med Sci ; 72(9): 1107-11, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20379087

RESUMEN

To evaluate the effects of IV fentanyl administration on the end-tidal sevoflurane concentration (ET(SEVO)) in thoroughbred racehorses, the ET(SEVO) required for internal fixation of longitudinal fractures was compared between horses anesthetized with sevoflurane-fentanyl (Group SF; n=9) and those anesthetized with sevoflurane alone (Group S; n=9). The loading dose of fentanyl (5.0 µg/kg) was administered over 15 min followed by a maintenance dose of fentanyl (0.1 µg/kg/min) throughout the operation in Group SF. The mean ET(SEVO) during the operation in Group SF (2.6 ± 0.2%) was significantly lower than in Group S (3.0 ± 0.3%). The plasma fentanyl concentrations (6.12 ± 0.88 to 7.78 ± 1.12 ng/ml) in 7 out of 9 horses in Group SF were stable and did not change significantly throughout the operation. The mean dobutamine infusion rate required for maintaining a mean arterial blood pressure between 60 and 80 mmHg during the operation in Group SF (0.56 ± 0.30 µg/kg/min) was significantly lower than in Group S (0.90 ± 0.16 µg/kg/min). The qualities of the recoveries were clinically acceptable, and serious complications were not observed in either group. In conclusion, continuous IV fentanyl administration reduced the sevoflurane requirement by 13% in thoroughbred racehorses undergoing orthopedic surgery; however, fentanyl was considered to be less effective in horses compared with other species.


Asunto(s)
Fentanilo/uso terapéutico , Enfermedades de los Caballos/cirugía , Éteres Metílicos/sangre , Procedimientos Ortopédicos/veterinaria , Anestésicos Intravenosos/administración & dosificación , Anestésicos Intravenosos/uso terapéutico , Animales , Presión Sanguínea/efectos de los fármacos , Fentanilo/administración & dosificación , Fracturas Óseas/cirugía , Fracturas Óseas/veterinaria , Frecuencia Cardíaca/efectos de los fármacos , Caballos , Infusiones Intravenosas , Fijadores Internos/veterinaria , Procedimientos Ortopédicos/métodos , Sevoflurano , Volumen de Ventilación Pulmonar/efectos de los fármacos
19.
Molecules ; 15(3): 1918-31, 2010 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-20336022

RESUMEN

In this manuscript, we report clear evidence for the generation of aromatic cation radicals produced by using [hydroxy(tosyloxy)iodo]benzene (HTIB) in fluoroalcohol solvents such as 2,2,2-trifluoroethanol (TFE) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP). The single-electron-transfer (SET) oxidation ability of HTIB to give cation radicals was first established by ESR and UV measurements. The reaction was broadly applied to various thiophenes, and unique thienyliodonium salts were directly synthesized by this method in excellent yields without the production of any harmful byproducts.


Asunto(s)
Derivados del Benceno/química , Sales (Química) , Espectroscopía de Resonancia por Spin del Electrón , Espectrofotometría Ultravioleta
20.
J Am Chem Soc ; 131(5): 1668-9, 2009 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-19191694

RESUMEN

A new strategy for mixed biaryl synthesis has been developed using the hypervalent iodine(III) reagents. The unique reactivities of the sigma-heteroaryl iodine(III) intermediates generated in situ are the key element for the unusual metal catalyst-free transformations and strict control of the product selectivities.


Asunto(s)
Derivados del Benceno/química , Naftalenos/química , Pirroles/química , Tiofenos/química , Derivados del Benceno/síntesis química , Yodo/química , Naftalenos/síntesis química , Compuestos Onio/química , Oxidación-Reducción , Pirroles/síntesis química , Tiofenos/síntesis química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA