Effect of different doses of prostaglandin E2 on intrauterine pressure and uterine motility during diestrus in experimental cows

Studies in human medicine proved the important role of prostaglandin E2, which stimulates uterine contractions in vivo and in vitro and has been extensively used to ripen the cervix around labor. We wanted to demonstrate that increasing the dosage of prostaglandin E2 (1.25 mg, 2.5 mg, 5 mg and 10 mg) provokes an increase in intrauterine pressure and uterine motility in cattle. Five healthy, lactating dairy cows were used as experimental animals for this study. Intrauterine pressure was recorded during the diestrus phase (1 recording per cow and diestrus phase) by means of a transcervically placed intraluminal pressure microtransducer. Physiologic uterine motility was recorded for 30 min, then placebo or one of the prostaglandin E2- dosages was administered through an indwelling catheter in the jugular vein, followed by a 2-h recording period (eight 15-min periods). Area under the curve (AUC), mean amplitude, frequency of pressure waves and intrauterine pressure were analyzed. Furthermore, we recorded protocols for monitoring heart and respiratory rates and side effects at 9 given examination times. Significant differences were found for the AUC, the mean amplitude and the intrauterine pressure (P < or = 0.05), whereas the number of pressure waves per 15 min did not differ significantly among treatments. Peak values for AUC, mean amplitude and intrauterine pressure were found during the first 15 min after administration of 10 mg of prostaglandin E2. Dose-effect curves showed that the 2.5 mg dosage provided the optimal ratio between myometrial stimulation and undesirable side-effects.     

Characterization of PR-10 genes from eight Betula species and detection of Bet v 1 isoforms in birch pollen

Background  

Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula) have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MS^E was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome.     

Recent advances in ABE fermentation: hyper-butanol producing Clostridium beijerinckii BA101

This is an overview of the mutant strain Clostridium beijerinckii BA101 which produces solvents (acetone–butanol–ethanol, ABE) at elevated levels. This organism expresses high levels of amylases when grown on starch. C. beijerinckii BA101 hydrolyzes starch effectively and produces solvent in the concentration range of 27–29 g l⁻¹. C. beijerinckii BA101 has been characterized for both substrate and butanol inhibition. Supplementing the fermentation medium (MP2) with sodium acetate enhances solvent production to 33 g l⁻¹. The results of studies utilizing commercial fermentation medium and pilot plant-scale reactors are consistent with the results using small-scale reactors. Pervaporation, a technique to recover solvents, has been applied to fed-batch reactors containing C. beijerinckii BA101, and solvent production as high as 165 g l⁻¹ has been achieved. Immobilization of C. beijerinckii BA101 by adsorption and use in a continuous reactor resulted in reactor productivity of 15.8 g l⁻¹ h⁻¹. Recent economic studies employing C. beijerinckii BA101 suggested that butanol can be produced at US$0.20–0.25 lb⁻¹ by employing batch fermentation and distillative recovery. Application of new technologies such as pervaporation, fed-batch culture, and immobilized cell reactors is expected to further reduce these prices. Journal of Industrial Microbiology & Biotechnology (2001) 27, 287–291. Received 12 September 2000/ Accepted in revised form 27 January 2001     

The effect of diethyl- -fluoroglutarate on phosphates and glutamate in slices of rabbit cerebral cortex

Abstract— The diethyl ester of α-fluoroglutarate (DEFG), an inhibitor of glutamate dehydrogenase, was prepared, and its effect on glutamate and phosphates in slices of rabbit cerebral cortex was examined. The primary effect of the drug on cortical slices incubating in a Krebs-Ringer glucose medium was to decrease the tissue levels of glutamate in association with decreased levels and turnover of high-energy phosphates. Assimilation of exogenous glutamate by the slices was partially blocked in the presence of the drug and severely depressed oxidative phosphorylation resulted when glutamate and DEFG were both present in the incubation mixture. The results suggested a significant relationship between the activity of cerebral glutamate dehydrogenase and oxidative phosphorylation. During incubation in a Krebs-Ringer glucose medium the endogenous pool of free amino acids in the cortical slice partitioned with the medium. Little or no glutamate, aspartate or GABA was present in the medium after incubation, but glycine, alanine, threonine, serine and glutamine did partition to varying degrees, with over one-half of the glutamine present in the incubation medium. With the exception of ‘leakage’ of aspartate, the partitioning patterns were relatively unaffected by the presence of added glutamate or DEFG.     

An overview of the serpin superfamily

Serpins are a broadly distributed family of protease inhibitors that use a conformational change to inhibit target enzymes. They are central in controlling many important proteolytic cascades, including the mammalian coagulation pathways. Serpins are conformationally labile and many of the disease-linked mutations of serpins result in misfolding or in pathogenic, inactive polymers.     

An in vitro study on spontaneous myometrial contractility in the cow during estrus and diestrus

Myometrial smooth muscle strips were collected from slaughtered cows in estrus and diestrus. Longitudinal and circular smooth muscle strips were mounted in organ baths and after equilibration time and 2 g preload, their physiologic contractility was recorded for 3 h. Area under the curve (AUC), mean amplitude (MA) and frequency of contractions (F) were studied. Differences between cycle phases, between muscle layers and over the recorded time period were statistically evaluated. In the cow, physiologic contractility patterns (measured as AUC and MA) of circular versus longitudinal myometrial strips are always different during the 3 h recording. Significant differences between estrus versus diestrus are only found for circular layers, but not for longitudinal layers. Significant differences over time are only found for longitudinal layers.