Cyclic vomiting syndrome in adults.

Cyclic vomiting syndrome (CVS) was initially described in children but can occur in all age groups. Cyclic vomiting syndrome is increasingly recognized in adults. However, the lack of awareness of CVS in adults has led to small numbers of diagnosed patients and a paucity of published data on the causes, diagnosis and management of CVS in adults. This article is a state-of-knowledge overview on CVS in adults and is intended to provide a framework for management and further investigations into CVS in adults.

Dietary protein concentration regulates the mRNA expression of chicken hepatic malic enzyme.

Chicken hepatic malic enzyme activity varies with dietary protein content. The mechanisms responsible for this alteration in activity are unclear. In a series of four experiments, broiler chicks were allowed free access for 1.5, 3, 6 or 24 h to a low (13 g/100 g diet), basal (22 g/100 g diet) or high (40 g/100 g diet) protein diet. The diets were isocaloric and had equal concentrations of dietary fat. Hepatic malic enzyme mRNA expression and enzyme activity as well as total liver lipid concentration were examined for each experimental duration. There were no differences in the expression of the mRNA for malic enzyme at 1.5 h, but at 3, 6 and 24 h, malic enzyme mRNA expression was significantly (P < 0.05) reduced in chicks fed the high protein diet and significantly enhanced in chicks fed the low protein diet compared with chicks fed the basal diet. Hepatic malic enzyme activities and total lipid concentration were not different among the chicks fed the different diets at 1.5 and 3 h. At 6 and 24 h, malic enzyme activity and total liver lipid concentration were both significantly greater in birds fed the low protein diet compared with levels in the birds fed the other two diets. In birds fed the high protein diet, malic enzyme activity and total liver lipid concentration were significantly reduced at 24 h compared with birds fed the basal diet. In a final experiment, the observed differences in malic enzyme mRNA expression at 6 h were confirmed when chicks were given access to isocaloric diets with the same protein levels as the initial 4 experiments, but with the dietary concentration of carbohydrate held constant. The results suggest that previously observed alterations in the activity of malic enzyme, which were correlated with dietary protein intake, are due to rapid changes in the mRNA expression of this enzyme.

The transcription factor Lmx1b maintains Wnt1 expression within the isthmic organizer.

Cells in the caudal mesencephalon and rostral metencephalon become organized by signals emanating from the isthmus organizer (IsO). The IsO is associated with the isthmus, a morphological constriction of the neural tube which eventually defines the mesencephalic/ metencephalic boundary (MMB). Here we report that the transcription factor Lmx1b is expressed and functions in a distinct region of the IsO. Lmx1b expression is maintained by the glycoprotein Fgf8, a signal capable of mediating IsO signaling. Lmx1b, in turn, maintains the expression of the secreted factor Wnt1. Our conclusions are substantiated by the following: (i) Lmx1b mRNA becomes localized to the isthmus immediately after Fgf8 initiation, (ii) Wnt1 expression is localized to the Lmx1b expression domain, but with slightly later kinetics, (iii) Fgf8-soaked beads generate similar domains of expression for Lmx1b and Wnt1 and (iv) retroviral-mediated expression of Lmx1b (Lmx1b/RCAS) maintains Wnt1 expression in the mesencephalon. Ectopic Lmx1b is insufficient to alter the expression of a number of other genes expressed at the IsO, suggesting that it does not generate a new signaling center. Instead, if we allow Lmx1b/RCAS-infected brains to develop longer, we detect changes in mesencephalic morphology. Since both ectopic and endogenous Lmx1b expression occurs in regions of the isthmus undergoing morphological changes, it could normally play a role in this process. Furthermore, a similar phenotype is not observed in Wnt1/RCAS-infected brains, demonstrating that ectopic Wnt1 is insufficient to mediate the effect of ectopic Lmx1b in our assay. Since Wnt1 function has been linked to the proper segregation of mesencephalic and metencephalic cells, we suggest that Lmx1b and Wnt1 normally function in concert to affect IsO morphogenesis.

The ability of "low G + C gram-positive" ruminal bacteria to resist monensin and counteract potassium depletion.

Gram-negative ruminal bacteria with an outer membrane are generally more resistant to the feed additive, monensin, than Gram-positive species, but some bacteria can adapt and increase their resistance. 16S rRNA sequencing indicates that a variety of ruminal bacteria are found in the "low G + C Gram-positive group," but some of these bacteria are monensin resistant and were previously described as Gram-negative species (e.g., Selenomonas ruminantium and Megasphaera elsdenii). The activity of monensin can be assayed by its ability to cause potassium loss, and results indicated that the amount of monensin needed to catalyze half maximal potassium depletion (K(d)) from low G + C gram-positive ruminal bacteria varied by as much as 130-fold. The K(d) values for Butyrivibrio fibrisolvens 49, Streptococcus bovis JB1, Clostridium aminophilum F, S. ruminantium HD4, and M. elsdenii B159 were 10, 65, 100, 1020, and 1330 nM monensin, respectively. B. fibrisolvens was very sensitive to monensin, and it did not adapt. S. bovis and C. aminophilum cultures that were transferred repeatedly with sub-lethal doses of monensin had higher K(d) values than unadapted cultures, but the K(d) was always less than 800 nM. S. ruminantium and M. elsdenii cells were highly resistant (K(d) > 1000 nM), and this resistance could be explained by the ability of these low G + C Gram-positive bacteria to synthesize outer membranes.

Hormonal correlates of sexual behavior and ovulation in male-induced and postpartum estrus in female prairie voles.

The purpose of the present study was a description of hormonal profiles in female prairie voles (Microtus ochrogaster) in estrus that was induced by male exposure versus postpartum estrus. Hormonal profiles are reported in sexually naive females and in sexually experienced females, as a function of varying amounts of coital stimulation and as a function of time since male exposure. Ovarian estradiol levels, uterine weights and uterine protein levels increased in virgin females after exposure to a male, were highest in females that showed lordosis, declined slowly when estrous females were isolated from males and decreased sharply following mating. Ovarian progesterone levels increased more rapidly following mating in females in male-induced estrus than in females in postpartum estrus. Serum progesterone levels did not increase significantly within 24 hr following mating, but were elevated by 72 hr after mating. These findings are discussed as they relate to the hormonal control of female sexual behavior.

Porcine cholesterol esterase, a multiform enzyme.

Cholesterol esterase (sterol-ester acylhydrolase, EC 3.1.1.13) has been purified from porcine pancreas by two methods, one of which was previously reported by Momsen, W.E. and Brockman, H.L. (Biochim. Biophys. Acta. 486 (1977) 102-113). Multiple forms of the enzyme were demonstrated throughout the course of both purification procedures. These forms hydrolyzed both p-nitrophenyl acetate as well as cholesteryl oleate. Isoelectric focusing was used to select one form of cholesterol esterase having a pI of 4.3 for further study. Using high-pressure liquid chromatography on a TSK Spherogel column this apparently homogeneous preparation of cholesterol esterase was separated into two components having molecular weights equal to 90 000 (peak I) and 45 000 (peak II). The number of each amino acid residue in peak I was double that of the corresponding residue in peak II, suggesting a dimer-monomer relationship. The N-terminal analyses showed that the first five amino acid residues were the same in peak I and peak II. The enzyme is a glycoprotein containing glucosamine, glucose, galactose, mannose and rhamnose; it is inhibited by diisopropyl fluorophosphate.

Performance of MA-matched nonretarded and retarded children on discrimination learning and transfer-shift tasks.

The effects of the nature of the relevant dimension, response mode, imagery, and age on discrimination learning and shift performance was examined. Three age groups were used, CA 8 years-MA 8 years, CA 5 years-MA 5 years. CA 8 years-MA 5 years. The latter group learned both intradimensional and extradimensional shifts slower than did the former two groups. Subsequent analyses suggested that the reason for the slower learning in the retarded group was their greater frequency of control by dominant dimensions and/or the initial control by novel stimuli. A second finding was related to the particular procedure employed. Children were required to either press a button to indicate which of two stimuli was correct or pick up the correct stimulus. Form-relevant but not color-relevant problems were facilitated by the pick-up procedure. These findings suggest that dimensional dominance may be a consequence of the procedures employed in previous reports where children were or were not permitted to manipulate the stimuli.