The effect of cortisol on the synthesis of prostaglandins (PGF2 alpha, PGE2) by human endometrial fibroblasts in vitro with and without addition of estradiol-17 beta or progesterone

Cortisol is known as a potent inhibitor of phospholipase A2 activity in several tissues. In fibroblast monolayer cell cultures from proliferative human endometrium cortisol alone does not affect the basal PGF2 alpha or PGE2 synthesis. After stimulation of PGF2 alpha production by 10(-7) mol/l estradiol-17 beta increasing concentrations of cortisol up to 10(-5) mol/l dosedependently reduce the PGF2 alpha production. Also the progesterone (10(-4) mol/l) stimulated increase of PGF2 alpha and PGE2 synthesis is inhibited by cortisol (10(-7) mol/l).     

Formation of prostaglandins by ovarian carcinomas

Tissue contents of prostaglandins (PG) PGE2, PGE2a and 6-keto-PGF1a (degradation product of PGI2) were determined in specimens of advanced human ovarian cancer (n = 11). The PG levels (ng/mg tissue protein) varied widley: PGE2 17-515; PGF2a 2-43 and 6-keto-PGF1a 5-105. Tumors of patients without response to chemotherapy contained more PGE2, PGF2a and 6-keto-PGF1a than did tumors responding to chemotherapy. PG production was investigated in two ovarian carcinoma-derived cell lines. The ability of these cells to synthesize PG varied depending on the cell density. An increase of cell number was associated with a decrease of PG yield. PG formation was inhibited by indomethacin in a concentration-dependent manner. The present study suggests that ovarian carcinoma cells form PG in vivo and vitro.     

Effect of the progesterone antagonist RU486 on human myometrial spontaneous contractility and PGI2 release

We studied the effect of antiprogesterone RU 486 on spontaneous uterine contractility and PGI₂ release with human myometrial strips superfused “in vitro”. A decrease of PGI₂ release into the superfusion medium was observed after 20 min superfusion. The inhibition was dose-dependent and reversible. After 20 min washing with tyrode medium without RU 486, the uterine strips recovered their initial rate of release. R5020, a progesterone agonist, did not affect PGI₂ release nor dexamethasone and testosterone. Parallel to the decrease of PGI₂ observed during RU 486 superfusion, the uterine spontaneous contraction frequency decreased, while the amplitude and duration of contractions increased. The alteration of uterine contractility was also rapid, dose-dependent and reversible. Modifications of uterine strip spontaneous contractility, similar to those induced by RU 486, were also observed with superfusions of R5020 at concentrations as low as 10⁻⁹M, dexamethasone (10⁻⁸M), but not with superfusions of testosterone. These observations are not in favour of a progesterone-receptor mediated effect of RU 486 in our model. The mechanism of action may be related to the antiprogesterone specific structure i.e. the bulky substituent at the C-11 position. The RU 486 effect on uterine strip contractility, mimicked by other steroids, could point to a non-specific lipid/membrane interaction. However, the fact that testosterone did not affect motility, may indicate a possible specificity of steroids having a 3 oxo pregnene structure.     

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.     

Assessment of cues potentially mediating host selection of Leptoglossus occidentalis on Pinus contorta

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Preliminary assessment of safety and effectiveness in humans of ProBiora3 ™, a probiotic mouthwash

Aims:  To conduct a pilot human clinical trial to assess the safety and to test the ability of a probiotic mouthwash, ProBiora³, to affect the levels of Streptococcus mutans and certain known periodontal pathogens in the mouth when administered twice daily over a period of 4 weeks.
Methods and Results:  The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 10⁶ and 10⁸ colony forming units each of Strep. oralis strain KJ3sm, Strep. uberis strain KJ2sm, and the spontaneous lactic acid-deficient variant of Strep. rattus , strain JH145. Substantial decreases in the levels of the marker bacteria were observed. No safety issues were noted with the twice daily application of this mouthwash.
Conclusions:  Despite the small number of subjects and the use of young, orally healthy adults, along with the inherent variability in the microbiological measurements, the probiotic mouthwash was able to substantially affect the levels of dental pathogens in saliva and periodontal pathogens in subgingival plaque.
Significance and Impact of the Study:  The results of this pilot human study suggest that the probiotic mouthwash product may be safe for daily use as an aid in maintaining both dental and periodontal health.     

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