RESUMEN
Cesarean scar pregnancy (CSP) is a rare complication that occurs in less than 1% of ectopic pregnancies, and uterine didelphys is one of the rarest uterine forms. We report a successful laparoscopic excision and repair of CSP in a woman with uterine didelphys and a double vagina. A 34-year-old gravida one, para one woman with a history of low transverse cesarean section presented to our hospital with a suspected CSP. She was confirmed to have uterine didelphys with a double vagina during an infertility examination 7 years earlier. Magnetic resonance imaging showed a 2.5-cm gestational sac-like cystic lesion in the lower segment of the right uterus at the cesarean scar. We decided to perform a laparoscopic approach after informing the patient of the surgical procedure. The lower segment of the previous cesarean site was excised with monopolar diathermy to minimize bleeding. We identified the gestational sac in the lower segment of the right uterus, which was evacuated using spoon forceps. The myometrium and serosa of the uterus were sutured layer-by-layer using synthetic absorbable sutures. No remnant gestational tissue was visible on follow-up ultrasonography one month after the surgery. This laparoscopic approach to CSP in a woman with uterine didelphys is an effective and safe method of treatment. In women with uterine anomalies, it is important to confirm the exact location of the gestational sac by preoperative imaging for successful surgery.
RESUMEN
Cyclopolymerization (CP) of 1,6-heptadiyne derivatives using the Grubbs catalysts has been known to afford conjugated polyenes in low yields in dichloromethane (DCM), the most common solvent for olefin metathesis polymerization and a good solvent for typical conjugated polymers. Based on our previous work that showed highly efficient CP using the Grubbs catalysts in tetrahydrofuran (THF), we developed a new polymerization system using weakly coordinating additives with the third-generation Grubbs catalyst in DCM. The polymerization efficiency of various monomers and their controls dramatically increased by adding 3,5-dichloropyridine, yielding polymers with narrow polydispersity indices (PDIs) at low temperatures. These new reaction conditions not only expand the monomer scope by resolving the solubility concerns of conjugated polymers but also more effectively reduced the chain transfer. Consequently, fully conjugated diblock copolymer was successfully prepared. Additionally, kinetic analysis has revealed that low CP efficiency in DCM resulted from the rapid decomposition of the propagating carbene. This decomposition was effectively suppressed by both pyridine additives and THF, suggesting that weakly coordinating additives stabilize the living chain end. Furthermore, we observed that the turnover number of CP was higher at lower temperatures (0-10 °C) than at ambient temperatures, consistent with the understanding that the lifetime of a propagating carbene is greater at lower temperatures. Steric protection was also shown to increase the stability of the propagating carbene, as shown by a higher turnover number for the 3,3-dimethyl-substituted 1,6-heptadiyne compared to the nonfunctionalized monomer.
RESUMEN
Two unprecedented phosphorus-containing iodinated polyacetylenes, phosphoiodyns A and B (1-2), were isolated from a Korean marine sponge Placospongia sp. Their structures were elucidated by spectroscopic data analysis. Phosphoiodyn A exhibited potent agonistic activity on human peroxisome proliferator-activated receptor delta (hPPARδ) with an EC(50) of 23.7 nM.
Asunto(s)
Hidrocarburos Yodados/aislamiento & purificación , Compuestos Organofosforados/aislamiento & purificación , PPAR delta/agonistas , Poliinos/aislamiento & purificación , Poríferos/química , Animales , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Hidrocarburos Yodados/química , Hidrocarburos Yodados/farmacología , Corea (Geográfico) , Biología Marina , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Poliinos/química , Poliinos/farmacologíaRESUMEN
Yeast dehydrogenases and reductases were overexpressed in Saccharomyces cerevisiae D452-2 to detoxify 2-furaldehyde (furfural) and 5-hydroxymethyl furaldehyde (HMF), two potent toxic chemicals present in acid-hydrolyzed cellulosic biomass, and hence improve cell growth and ethanol production. Among those enzymes, aldehyde dehydrogenase 6 (ALD6) played the dual roles of direct oxidation of furan derivatives and supply of NADPH cofactor to their reduction reactions. Batch fermentation of S. cerevisiae D452-2/pH-ALD6 in the presence of 2g/L furfural and 0.5 g/L HMF resulted in 20-30% increases in specific growth rate, ethanol concentration and ethanol productivity, compared with those of the wild type strain. It was proposed that overexpression of ALD6 could recover the yeast cell metabolism and hence increase ethanol production from lignocellulosic biomass containing furan-derived inhibitors.