Distribution of flehmen reactions of the bull throughout the bovine estrous cycle

A bull's flehmen reactions were recorded daily during 20-minute contact with 3 cows for nine months. During estrous periods (?3 to +1 days) there were 174 observations: 28.2% without flehmen, 21.2% with a single reaction, and 50.6% with repeated reactions. During nonestrous periods there were 624 observations: 49.0% without flehmen, 40.4% with a single reaction, and 10.6% with repeated reactions. Average numbers of all and repeated reactions during estrous periods were 2.11±2.30 and 1.90±2.43 respectively. Corresponding values for nonestrous periods, 0.70±0.93 and 0.29±0.93, were significantly lower (P<0.01).The results suggest that either the estrous pheromone(s) also occur(s) for a limited time or in limited amounts during nonestrus or that flehmen is not a very specific response to the estrus-related odors. In either case, the study of sexual pheromones should encompass other methods as well as flehmen observation.     

Two body fluids containing bovine estrous pheromone(s)

Bovine females produce an estrous pheromone(s). Because onlyother cattle are reliable detectors of the pheromone(s), weevaluated various body fluids (cervico-vaginal mucus, serumand vulval skin gland secretion) with a bull behavioral assayin the absence of a female. It specified 15 behaviors involvingattraction to the body fluids, detection of the stimulus, andsubseqeunt sexual preparation responses. These behaviors werestereotypical and occurred in a specific sequence. We discoveredthat serum (10–15 ml) taken at estrus was behaviorallypositive, as well as vulval skin glands secretion (<1 mlon a swab, dissolved in 5 ml distilled water). We postulatethat vulval skin glands may be a specialized site for the productionor concentration of the pheromone or that the blood transportsthe pheromone(s) either from vulval skin glands or another source.     

A technique for the immunohistochemical localization of prostaglandin E.

Prostaglandin E (PGE) has been localized via the unlabeled antibody technique in freeze-dried and ethanol-fixed cryostat sections. Discrete perivascular and stromal localization was present in the uterus prepared by the method presented, but not in classically fixed specimens. Absorption of the anti-PGE by addition of free PGE was ineffective; whereas, removal of PGE-reactive antibodies from the anti-serum was effectively accomplished with an Affigel-101-PGE immunoadsorbant column.     

Characterization of Two Cytosolic Diacylglycerol Kinase Forms

Abstract: Two forms of rat brain cytosolic diacylglycerol kinase (EC 2.7.1.107) were separated by heparin-agarose column chromatography. These forms, designated DGK-I and DGK-II, were not interconvertible as determined by rechromatography. DGK-I and DGK-II had respective molecular masses of 88 and 180 kDa, as measured by Sepharose 6B chromatography. Both forms preferred diacylglycerol over monoacylglycerol and were insensitive to R59022. DGK-II, but not DGK-I, was activated by an activator substance prepared from chicken egg yolk. DGK-II was activated by a rat brain cytosolic activator and was exclusively sensitive to 5'-AMP-mediated inactivation. Further studies revealed that these two forms had the following distinct characteristics: (a) substrate specificity, (b) inhibition by heparin, (c) sensitivity to lysine-containing polyamino acids, and (d) responses to different phospholipids. In general, DGK-II was more responsive to various inhibitors and activators, making it a prime candidate for a regulatable enzyme.     

XRate: a fast prototyping, training and annotation tool for phylo-grammars

Background  

Recent years have seen the emergence of genome annotation methods based on the phylo-grammar, a probabilistic model combining continuous-time Markov chains and stochastic grammars. Previously, phylo-grammars have required considerable effort to implement, limiting their adoption by computational biologists.