Sperm factor induces intracellular free calcium oscillations by stimulating the phosphoinositide pathway.

Injection of a porcine cytosolic sperm factor (SF) or of a porcine testicular extract into mammalian eggs triggers oscillations of intracellular free calcium ([Ca(2+)](i)) similar to those initiated by fertilization. To elucidate whether SF activates the phosphoinositide (PI) pathway, mouse eggs or SF were incubated with U73122, an inhibitor of events leading to phospholipase C (PLC) activation and/or of PLC itself. In both cases, U73122 blocked the ability of SF to induce [Ca(2+)](i) oscillations, although it did not inhibit Ca(2+) release caused by injection of inositol 1,4,5-triphosphate (IP(3)). The inactive analogue, U73343, had no effect on SF-induced Ca(2+) responses. To determine at the single cell level whether SF triggers IP(3) production concomitantly with a [Ca(2+)](i) rise, SF was injected into Xenopus oocytes and IP(3) concentration was determined using a biological detector cell combined with capillary electrophoresis. Injection of SF induced a significant increase in [Ca(2+)](i) and IP(3) production in these oocytes. Using ammonium sulfate precipitation, chromatographic fractionation, and Western blotting, we determined whether PLCgamma1, PLCgamma2, or PLCdelta4 and/or its splice variants, which are present in sperm and testis, are responsible for the Ca(2+) activity in the extracts. Our results revealed that active fractions do not contain PLCgamma1, PLCgamma2, or PLCdelta4 and/or its splice variants, which were present in inactive fractions. We also tested whether IP(3) could be the sensitizing stimulus of the Ca(2+)-induced Ca(2+) release mechanism, which is an important feature of fertilized and SF-injected eggs. Eggs injected with adenophostin A, an IP(3) receptor agonist, showed enhanced Ca(2+) responses to CaCl(2) injections. Thus, SF, and probably sperm, induces [Ca(2+)](i) rises by persistently stimulating IP(3) production, which in turn results in long-lasting sensitization of Ca(2+)-induced Ca(2+) release. Whether SF is itself a PLC or whether it acts upstream of the egg's PLCs remains to be elucidated.

Does smelling granny relieve depressive mood? Commentary on "Rapid mood change and human odors".

Chen and Haviland-Jones claim if you're down/You needn't be depressed and mope around/Check out Granny's smell/It'll make you feel well/One problem: no supporting evidence was found.

Self-efficacy enhanced preoperative instruction.

Perioperative nurses traditionally have helped patients cope with the adversities of surgery through preoperative instruction. The authors conducted a study to determine whether an efficacy-enhancing preoperative teaching protocol was effective in increasing preoperative self-efficacy in patients scheduled to undergo laparoscopic cholecystectomy procedures with general anesthesia. The subjects were 60 surgical patients in a 156-bed community hospital located in the midwestern United States. Analysis of covariance indicated there were no significant differences between groups after controlling for preoperative self-efficacy. Further research is needed to determine whether an efficacy-enhancing teaching protocol can improve selected short- and long-term outcomes in surgical patients.

Diethanolamine absorption, metabolism and disposition in rat and mouse following oral, intravenous and dermal administration.

1. The disposition of [14C]diethanolamine (DEA) (1) was determined in rat after oral, i.v. and dermal administration, and in mouse after dermal administration. 2. Oral administration of DEA to rat was by gavage of 7 mg/kg doses once and after daily repeat dosing for up to 8 weeks. Oral doses were well absorbed but excreted very slowly. DEA accumulated to high concentrations in certain tissues, particularly liver and kidney. The steady-state of bioaccumulation was approached only after several weeks of repeat oral dosing, and the half-life of elimination was approximately 1 week. 3. DEA was slowly absorbed through the skin of rat (3-16% in 48 h) after application of 2-28 mg/kg doses. Dermal doses ranging from 8 to 80 mg/kg were more readily absorbed through mouse skin (25-60%) in 48 h of exposure, with the percent of the applied dose absorbed increasing with dose. 4. Single doses (oral or i.v.) of DEA were excreted slowly in urine (c. 22-25% in 48 h) predominantly as the parent compound. There was minimal conversion to CO2 or volatile metabolites in breath. The profile of metabolites appearing in urine changed after several weeks of repeat oral administration, with significant amounts of N-methylDEA and more cationic metabolites appearing along with unchanged DEA.

p,p'-Dichlorodiphenyl sulfone metabolism and disposition in rats.

p, p'-Dichlorodiphenyl sulfone (DDS) is a lipophilic monomer used extensively in the synthesis of high temperature plastics. Studies of the fate of uniformly labeled [14C]DDS in the rat have established that it is readily absorbed from the gastrointestinal tract, distributed to all tissues examined, and concentrated in adipose tissue. After intravenous administration of 10 mg/kg and determination of the time course of DDS distribution, increasing accumulation of DDS in adipose was observed up to 24 hr, followed by slow elimination with a half-life of approximately 12 days. DDS equivalents in tissues were primarily (> 90%) parent compound, whereas excreted DDS equivalents were primarily (> 80%) present as metabolites. On repeat oral dosing at 10 mg/kg, levels of DDS in tissues seemed to reach steady state after approximately 2 weeks, at which time the concentrations in adipose reached 265 micrograms/g tissue. Hepatic cytochrome P450 (CYP) content, ethoxyresorufin O-deethylase activities, and levels of metabolites arising from phase I metabolism were doubled after repeat oral administration of DDS, but benzphetamine N-demethylase activity was unchanged. Thus, it seems that DDS induces CYP1A forms, but not CYP2B isozymes. DDS-derived radioactivity was excreted primarily in feces and to a lesser extent in urine as a phenolic metabolite and its glucuronide. The aglycone of this glucuronide was isolated and characterized by NMR and MS as 3-hydroxy-4,4'-dichlorodiphenyl sulfone.

Evaluating a revised self-efficacy scale for preoperative patients.

Nurses conduct preoperative teaching to help patients cope with the adversities of surgery. Self-efficacy can predict an individual's behavior in aversive situations (eg, surgery); therefore, assessing patients' self-efficacy is one way perioperative nurses can plan patient care and help patients through the surgical experience. This study expands on the results of a previous evaluation of a preoperative self-efficacy scale. The content and face validity of the revised 15-item scale used in this study were assessed before the instrument was administered to preoperative patients. Evidence supports the validity of the multidimensional instrument. Internal consistency estimates > or = .84 support the subscales' reliability.

Evaluation of retinoid lactones as topical therapeutic agents in dermatology.

PURPOSE: Optimization of the therapeutic ratio of analogs of the topically active 11-cis, 13-cis-12-hydroxymethylretinoic acid, delta-lactone (1) relative to antihyperproliferation and antihyperkeratinization vs. toxicity. METHODS: Nine analogs of 1, in which variations were made in the lipophilic cyclohexenyl moiety or in the lactone ring, were evaluated for topical activity against hyperkeratinization, inhibition of TPA-induced DNA synthesis and for skin irritation. RESULTS: Although more potent lactones than the parent lactone 1 were identified, none possessed the favorable therapeutic ratio associated with 1. CONCLUSIONS: The delta-lactone 1 possesses unique molecular features responsible for its desirable therapeutic ratio as an antihyperproliferative and antihyperkeratotic agent. In view of its very low systemic retinoid toxicity and the absence of any systemic toxicity, this lactone may be a good candidate for use in the topical treatment of acne.

Evaluation of a self-efficacy scale for preoperative patients.

Self-efficacy has been validated as a predictor of an individual's behavior in aversive situations. Traditionally, nurses have conducted preoperative instruction to help patients cope with the adversities of surgery. Assessing patients' self-efficacy is an additional way to assist them through the experience of surgery and plan their care. This study developed and tested an instrument to measure self-efficacy in adult preoperative patients. The instrument consists of two subscales: a 16-item efficacy expectation subscale and a 16-item outcome expectation subscale. The instrument was administered to 200 surgical patients to obtain descriptions of item characteristics, internal consistency reliability, and beginning construct validity. Evidence supports the validity and reliability of both self-efficacy subscales. The revised instrument can assist perioperative nurses in assessing preoperative patients' self-efficacy.

Preoperative self-efficacy and postoperative behaviors.

Preoperative instruction has been found to decrease postoperative complications; however, the mechanisms through which preoperative instruction exerts its effects remain unknown. In this study, the relationship between preoperative self-efficacy and postoperative behaviors was investigated. Subjects were 68 cholecystectomy patients. Subjects' scores on the efficacy expectations subscale were related significantly to postoperative deep breathing, ambulation, and recall of expected events; scores on the outcome expectations subscale were related significantly to postoperative requests for pain medication. Self-efficacy theory provided a link between self perceptions and behavior and may be the mechanism through which preoperative instruction exerts its effects.