Replacement of acetonitrile by ethanol as solvent in reversed phase chromatography of biomolecules.

Acetonitrile, which is a by-product of acrylonitrile synthesis, is the commonly used solvent in ion-pair reversed phase chromatography. In consequence of the decreasing demand for acrylonitrile due to the financial crisis, a worldwide shortage of acetonitrile is observed. Therefore, the aim of this study was to establish ion-pair reversed phase chromatographic assays using alternative eluents for acetonitrile and to decrease costs incurred hereby. We compared the performance of ion-pair reversed phase chromatography using acetonitrile with the alternative eluents methanol, ethanol and n-propanol, using monolithic reversed phase C5 as well as C18 chromatography columns. We used triethylammonium acetate (TEAA) and tetrabutylammonium sulfate (TBA) as representative cationic ion-pair reagents and trifluoroacetic acid (TFA) as representative anionic ion-pair reagent. For covering a large field of applications, we fractionated representative low, middle and high-molecular weight biomolecules, in particular dinucleoside polyphosphates, peptides, proteins and tryptic digested human serum albumin. Whereas the chromatographic characteristics of both methanol and n-propanol were partly insufficient, ethanol was characterised equally or partly even better in the matter of elution strength and separation quality compared to the eluent water-acetonitrile. In conclusion, ethanol is an appropriate alternative for acetonitrile in ion-pair reversed phase chromatography of biomolecules.

[Preventive intravenous nitroglycerin administration in cesarean section to facilitate fetal extraction of infants between 500 and 1500 g--are there negative effects on the newborn infant?]. / Prophylaktische intravenöse Nitroglycerinapplikation bei der Sectio caesarea zur Erieichterung der Entwicklung von Kindern zwischen 500 und 1500 g--gibt es negative Effekte für das Neugeborene?

BACKGROUND: Preterm infants should be delivered with as little trauma as possible. Fetal extraction during cesarean delivery can be facilitated by modification of the incision or by use of short-term tocolytic agents. A possible alternative to intravenous administration of beta-mimetics is i.v. application of nitroglycerin to induce rapid uterine relaxation. This has been recommended by various clinical teams, but with relatively little experience being available regarding preterm births. PATIENTS AND METHODS: Retrospective analysis of the perinatal data for all single neonates weighing 500 to 1500 g delivered by cesarean section at the Berlin-Neukölln Hospital in the period from 6/1995 to 9/1999 following prophylactic intraoperative i.v. application to the mother of 0.2 mg nitroglycerin (n = 55). Control groups: 1. All infants weighing 500 to 1500 g delivered by cesarean section at the Berlin-Neukölln Hospital with no intraoperative application of nitroglycerin (n = 38); 2. All infants weighing 500 to 1500 g delivered by cesarean section included in Berlin perinatal statistics (BePE) 1993-1998 (n = 715). RESULTS: There were no differences between the groups in terms of Apgar scores or the incidence of arterial umbilical pH values < or = 7.10 or of maternal blood loss > 1000 ml. Within the nitroglycerin group, in a shorter interval between nitroglycerin application and cutting of umbilical cord (< or = 3 min: n = 42; > 3 min: n = 13) 1-minute Apgar scores < 7 were observed more rarely, but no differences in arterial umbilical pH values < or = 7.10. CONCLUSIONS: 1. Intraoperative nitroglycerin application during cesarean section has no unfavorable effect on the condition of newborns < 32 SSW or between 500 and 1500 g. 2. The incidence of intraoperative maternal blood loss > 1000 ml was not increased. 3. Differences in the interval between nitroglycerin application and cutting of the umbilical cord have no clinically relevant effects on Apgar scores or arterial umbilical pH.

[Use of a stapling device in abdominal cesarean section]. / Anwendung eines Klammergerätes bei der abdominalen Schnittentbindung.

This is a report on the use of a stapling device for caesarean sections. The device can be inserted right and left after a very small median uterotomy. It cuts the uterine wall and at the same time places clips on the edges of the wound. The clips are made of a hydrolysable material that can be absorbed in the tissue and can also be used for surgical stitching. Haemostasis is definitely assured. No adverse reactions or disadvantages for the patients have been noticed to date.

[Diagnosis of feto-maternal macrotransfusion--a case report]. / Zur Diagnostik der feto-maternalen Makrotransfusion--Ein Fallbericht.

Fetal heart rate monitoring traces showing sinusoidal pattern associated with a feto-maternal macrotransfusion of about 200 ml blood are described.