Uterine rupture in patients with a history of multiple curettages:Two case reports

BACKGROUND Uterine rupture is a serious obstetric emergency,a severe event,and a serious threat to maternal and fetal life.It is a rare and not well characterized by the fact that multiple operations of uterine cavities contribute to uterine rupture during pregnancy.Atypical uterine rupture is easily misdiagnosed as other obstetric or surgical diseases.In current guidelines,abdominocentesis is a contraindication for late pregnancy.Therefore,the cases presented in this report provide new ideas for clinical diagnosis and treatment of uterine rupture.CASE SUMMARY Case 1,a 34-year-old woman(gravida 5,para 2),32 wk and 4 d of gestation,presented with acute upper abdominal pain for 8 h with nausea and vomiting.Computed tomography(CT)revealed pelvic and abdominal effusion.We extracted 3 mL unclotted blood from her abdominal cavity.An emergency caesarean section was performed.A uterine rupture was found,and the fimbrial portion of the left fallopian tube was completely adhered to the rupture.The prognosis of both the mother and the infant was good.Case 2,a 39-year-old woman(gravida 10,para 1)at 34 wk and 3 d of gestation complained of persistent lower abdominal pain for half a day.Her vital signs were normal.CT revealed a high probability of pelvic and abdominal hemoperitoneum.We extracted 4 mL dark red blood without coagulation.An emergency laparotomy was performed.Uterine rupture was identified during the operation.Postoperative course in both the mother and infant was uneventful.CONCLUSION For pregnant women in the second or the third trimester with persistent abdominal pain,abdominal effusion,fetal distress and even fetal death,the possibility of uterine rupture should be highly suspected.CT can identify acute abdominal surgical or gynecological and obstetric diseases.Abdominocentesis is helpful for diagnosing and clarifying the nature of effusion,but its clinical value need to be confirmed by further clinical studies.

Behavior of adsorbed diphenyl-sulfide on the Pd/C catalyst for o-chloronitrobenzene hydrogenation

A series of diphenyl-sulfide （Ph2S）-immobilized Pd/C catalysts （Pd-Ph2Scx）/C） were prepared using the wetness-impregnation and immobilization method. Pd-Ph2S（x）/C catalysts employed for the hydro- genation of o-chloronitrobenzene showed very high selectivity. The structure of Pd-Ph2Scx）/C with different molar ratio of ligand （x-values） was characterized by XPS and TG-DSC-MS. The results suggest a ＂saturated＂ surface ratio of Ph2S/Pd （about 0.3） was formed on the Pd-Ph2S（x）[C catalysts surface. The Ph2S immobilized on the Pd particle is quite stable, and the desorption of Ph2S or dissociative loss of phenyl group was only found at temperatures above 500 K. The possible catalytic mechanism of the Pd-Ph2S（x）/C catalyst was also discussed.

The promoting role of minor amount of water in solvent-free hydrogenation of halogenated nitrobenzenes

This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.

Nitridation:A simple way to improve the catalytic performance of hierarchical porous ZSM-5 in benzene alkylation with methanol

Nitrided hierarchical porous ZSM-5 was synthesized by nitridation of hierarchical porous ZSM-5 with flowing ammonia at elevated temperature.The samples were characterized by XRD,SEM,Nitrogen sorption isotherms,NH3-TPD and Py-IR,and evaluated in alkylation of benzene and methanol.The result indicated that the high specific surface area of parent ZSM-5 was maintained,while the Bronsted acidity was effectively adjusted by nitridation.Moreover,the high suppression of ethylbenzene was observed on nitrided catalyst and this could be attributed to the decrease of Bronsted acidity which suppressed the methanol to olefins reactions.

Selective hydrogenation of dimethyl maleate to tetrahydrofuran over Cu/SiO_2 catalyst:Effect of Cu^+ on the catalytic performance

Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic performance.The composition,structure and copper valence state were characterized by means of BET,XRD,XPS,FTIR,N2O-titration.It was found that the Cu/SiO2 prepared by ammoniaevaporation（AE） method had much higher TOF value than that prepared by wetness-impregnation（WI）with the same THF selectivity.The higher TOF value was attributed to the coexistence of Cu^＋ and Cu^0species in the activated AE-Cu/SiO2.while only Cu° species existing in the activated Wl-Cu/SiO2.Researches suggest that Cu^＋ can adsorb and polarize the C=0 bond of DMM.It is concluded that Cu°could be the main active site and the synergistic effect between Cu^0 and Cu^＋ could contribute to hydrogenation of DMM to THF.