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Objectives: Pregnant baboons were studied to determine the precise time of the switch from myometrial contractures to contractions in relation to photoperiod after laparotomy and at parturition. We compared the patterns recorded in baboons to those we have previously reported in pregnant rhesus monkeys to determine fundamental primate characteristics.Methods: Seven pregnant baboons (126–160 days’ gestation) were instrumented with femoral arterial and venous catheters and electrodes for myometrial electromyogram. All animals were subjected to a 14-hour light:10-hour dark photoperiod. Myometrial activity was monitored using a computer-based data acquisition system. Onset time for all switches was noted and standardized against time of lights off. Animals were studied at three stages of pregnancy (stage 1, first 10 days after laparotomy; stage 2, more than 10 days after laparotomy and more than 10 days before cesarean; and stage 3, 10 days before cesarean section or vaginal delivery).Results: All baboons demonstrated myometrial switches for a variable number of days preceding parturition. Onset of darkness was 0 hours. Average time of stage 1 switch onset was 2.17 ± 0.60 hours and was not different from stage 3 switch onset, which was −1.00 ± 0.27 hours.Conclusions: Myometrial contractile patterns showed clear photoperiodicity in the switch from contractures to contractions in late pregnancy in the baboon. The relationship of the switch from contractures to contractions was not altered by surgical laparotomy. There was a significant difference in the time of switch in relation to photoperiod between pregnant rhesus monkeys and baboons. However, the fact that a significant photoperiod exists in both species indicates a fundamental similarity in the switch from contractures to contractions in primate pregnancy. [Copyright &y& Elsevier]

Purpose: The impact of the COVID-19 pandemic on healthcare providers includes physical, psychological, financial, and childcare issues. The purpose of this qualitative study was to explore the experiences of dental hygienists returning to clinical practice after the March 2020 closure due to the COVID-19 pandemic. Methods: A qualitative phenomenological research design was used with virtual focus groups. Clinical dental hygienists who had worked a minimum of 3 days a week prior to dental practice closures in March 2020 and had returned to work in May 2020 were invited to participate through purposive sampling on dental hygiene social media sites. Demographic data was collected prior to a one-hour focus group session. Two investigators independently analyzed and coded the data using a qualitative data analysis software program. The themes identified were used to generate a description of the major findings. Results: Data saturation was achieved with (n=35) participants for a total of 13 focus groups. Most participants were female (89%), and the average age was 40 years. The following major themes were identified: physical issues; emotional; adherence to infection control protocols; fear of contracting/transmitting COVID-19; financial stress; our career was marginalized; and let's get back and make money. Conclusion: Dental hygienists experienced similar physical and mental health stressors as other health care professionals upon returning to work during the COVID-19 pandemic, however dental hygienists also reported feeling marginalized and undervalued. Results from this study suggest that dental hygienists need both personal and workplace support to manage the issues resulting from the COVID-19 pandemic in order to retain them in the workforce. [ABSTRACT FROM AUTHOR]

A number of compounds have been added to toothpastes to inhibit plaque regrowth. The inclusion of cationic antiseptics, such as chlorhexidine, poses formulation difficulties because of interactions with other ingredients particularly anionic detergents. More recently, Triclosan/zinc citrate formulations have been shown effective plaque inhibitors. The aim of this study was to compare a commercially available 0.2% Triclosan/0.5% zinc citrate toothpaste with a number of experimental 0.5% chlorhexidine/detergent toothpastes for effects on plaque regrowth over 4 days. Subjects rendered plaque free at each baseline rinsed twice a day with toothpaste slurries and disclosed plaque was scored at the end of each period. All toothpastes significantly reduced plaque by comparison with a control toothpaste, but were significantly less effective than a 0.2% chlorhexidine rinse. Some significant differences in favour of one chlorhexidine toothpaste were noted but these were small in magnitude. Whether the plaque inhibition obtained with Triclosan/zinc citrate toothpaste was greater than would be expected from other commercially available preparations cannot be determined from this study and is the subject of a further investigation. [ABSTRACT FROM AUTHOR]

The analogues of the coenzyme NADP+, nicotinamide-8-bromo-adenine dinucleotide phosphate (Nbr8ADP+) and 3-iodopyridine-adenine dinucleotide phosphate (io3PdADP+), were prepared. Nbr8ADP+ was found to be active in the hydrogen transfer and io3PdADP+ is a coenzyme competitive inhibitor for 6-phosphogluconate dehydrogenase. The binding of NADP+, NADPH and NADPH together with 6-phosphogluconate as well as that of both analogues to crystals of the enzyme 6-phosphogluconate dehydrogenase has been investigated at 0.6-nm resolution using difference electron density maps. The molecules bind in a similar position in a cleft in the enzyme subunit distant from the dimer interface. The orientation of the coenzyme in the site has been determined from the io3pdADP+-NADP+ difference density. The ternary complex difference density extends beyond that of the nicotinamide moiety of the coenzyme and tentatively indicates substrate binding. No clear identification of the bromine atom of Nbr8ADP+ can be made. How- ever, the analogue is bound more deeply in the cleft than is NADP+. The NADPH density is the most clearly defined and has thus been used to fit a molecular model using an interactive graphics system, checking for preferred geometry. A possible conformation is presented which is significantly different from that of NAD+ in the lactate dehydrogenase ternary complex. [ABSTRACT FROM AUTHOR]

The article describes English, French, and Japanese business letter writing. English business letter writing is reader oriented. The purpose of a business letter is to attempt to get the reader to appreciate the benefits of doing what that writer wants. It is a medium through which ideas are made acceptable to the reader. French business letter writing in writer oriented. The primary virtues of the French business letter are prudence, conciseness, and precision. It is extremely important to convey the required degree of respect and the writer's expectations of the response. Japanese business letter writing is oriented to the relationship, or the space, between the writer and the reader. The concern is with the format and language which will most effectively establish or maintain the appropriate relationship between reader and writer. A Japanese business letter consists of three parts, an introduction, body and conclusion. The body of the Japanese business letter consists of a statement of the reason for writing.

In vitro culture of VFNT Cherry tomato sepals (calyx) at 16–21 °C results in developmental changes that are similar to those that occur in fruit tissue [10]. Sepals become swollen, red, and succulent, produce ethylene, and have increased levels of polygalacturonase RNA. They also produce many flavor volatiles characteristic of ripe tomato fruit and undergo similar changes in sugar content [11]. We examined the expression of the tomato AGAMOUS gene, TAG1, in ripening, in vitro sepal cultures and other tissues from the plant and found that TAG1 RNA accumulates to higher levels than expected from data from other plants. Contrary to reports on the absence of AGAMOUS in sepals, TAG1 RNA levels in green sepals from greenhouse-grown plants is detectable, its concentration increasing with in vitro ripening to levels that were even higher than in red, ripe fruit. Sepals of fruit on transgenic tomato plants that expressed TAG1 ectopically were induced by low temperature to ripen in vivo, producing lycopene and undergoing cell wall softening as is characteristic of pericarpic tissue. We therefore propose that the induction of elevated TAG1 gene expression plays a key role in developmental changes that result in sepal ripening. [ABSTRACT FROM AUTHOR]

Objective:We tested the hypothesis that betamethasone is more potent than dexamethasone in inducing the essential mechanisms of parturition in sheep.Methods:Twenty-one sheep were instrumented under general anesthesia with maternal and fetal arterial and venous catheters and myometrial electromyogram electrodes at 117 days' gestation (dGA). At 125 dGA at 12:00 PM, after 2 days of baseline recording, either saline (n = 7, control group), betamethasone (n = 7), or dexamethasone (n = 7) was administered into the fetal jugular vein at a rate of 10 μg/hour. A total dose of 0.48 mg was given over the next 48 hours. The animals underwent autopsy 3 days after the end of the infusion period (130 dGA), or earlier if labor resulted from the glucocorticoid administration. Daily maternal and fetal arterial blood samples (4 mL) for hormone measurement were taken at 10:00 AM throughout the study period. Additional arterial blood samples were taken if the animal developed labor. Maternal plasma progesterone and fetal ACTH and cortisol concentrations were measured by radioimmunoassay, and corticosteroid-binding globulin (CBG) binding capacity was determined by saturation analysis. Myometrial activity was monitored continuously throughout the experimental protocol.Results:All seven betamethasone-treated animals developed labor after the glucocorticoid infusion regimen. In contrast, only two of seven dexamethasone-treated animals developed labor. Fetal treatment with betamethasone produced a greater and earlier fall in maternal plasma progesterone than fetal treatment with dexamethasone. Both betamethasone and dexamethasone treatments elevated fetal plasma CBG to similar binding capacities. Elevated fetal plasma ACTH and cortisol concentrations at the end of the infusion period in both betamethasone- and dexamethasone-treated animals were not related to the development of labor-type contractions.Conclusion:These data support the hypothesis that betamethasone is more potent than dexamethasone in inducing the essential mechanisms of parturition in sheep. [ABSTRACT FROM PUBLISHER]

Objective:Our purposes were to asses the effects of prostaglandin (PG) E2 and PGF2α on myometrial contractility in pregnant sheep and baboons in an in vitro superfusion study, and to characterize further the PGE-sensitive (EP) receptor subtype involved in the myometrial response to PGE2 by using the selective prostanoid EP2 agonist AH 13205.Methods:Strip preparations of uterine muscle from 15 sheep (107-145 days' gestational age) and ten baboons (158-185 days' gestation) were studied. Cumulative concentration-response curves (CRC) were constructed to oxytocin (4.2 pmol/L to 0.42 μmol/L, PGE2 (0.1 nmol/L to 1 μmol/L), and PGF2α (1 nmol/L to 100 μmol/L), and 50% effective concentration (EC50) values (mean and 95% confidence interval) were calculated. We also tested the hypothesis that PGE2-induced myometrial relaxation in pregnant baboons could be mediated by EP2-prostanoid receptors. Myometrial strips were stimulated by oxytocin (0.42 nmol/L), and CRCs to the EP2-agonist AH 13205 (0.1 nmol/L to 10 μmol/L) were constructed.Results:Prostaglandin F2α stimulated myometrial activity in a concentration-related fashion in all preparations from both sheep and baboons. The EC50 in the sheep myometrium for PGF2α (52 nmol/L, 95% confidence interval [CI] 25-110) was significantly (P < .05) lower than that in baboon myometrium (183 nmol/L, 95% CI 93-355). Oxytocin stimulated myometrial activity in preparations of both sheep (EC50 = 0.29 nmol/L, 95% CI 0.11-0.71) and baboon (EC50 = 0.31 nmol/L, 95% CI 0.18-0.52). In contrast, responses to PGE2 were species-related: PGE2 caused concentration-related stimulation of myometrial activity in sheep tissue (EC50 = 3.2 nmol/L, 95% CI 2.0-5.0), but induced concentration-related inhibition of activity in baboon myometrium (50% inhibitory concentration [IC50] = 21 nmol/L, 95% CI 2.2-203). A concentration-related inhibitory response to AH 13205 (IC50 = 3.56 nmol/L, 95% CI 1.28-5.99) was obtained in the baboon. In contrast, AH 13205 failed to inhibit comparable myometrial strip preparations from pregnant sheep.Conclusions:The present studies suggest that both sheep and baboon myometrium contain prostanoid receptors that mediate stimulation. In addition, baboon myometrium, like that from the human, contains AH 13205-sensitive EP receptors (EP2 receptors), which mediate inhibition. The pregnant baboon may therefore represent a suitable animal model for investigations into the use of EP2 agonists for the prevention of premature labor in humans. [ABSTRACT FROM PUBLISHER]

This article describes the processes involved in the development of an information retrieval system for the Speech Communication Association. It attempts to show the use of the computer in several phases of this development. Essentially, the steps involved in this process are: 1. Delimit the concepts being used in the data base. 2. Organize these concepts into a faceted thesaurus. 3. Index the abstracts in the data base with the appropriate concepts. 4. Create a computer system that will retrieve abstracts indexed with the descriptor terms. The system is now operational, and the data base and thesaurus are being continuously up-dated. [ABSTRACT FROM AUTHOR]

GSK3532795 (formerly BMS-955176) is a second-generation HIV-1 maturation inhibitor that has shown broad spectrum antiviral activity and preclinical PK predictive of once-daily dosing in humans. Although efficacy was confirmed in clinical trials, the observation of gastrointestinal intolerability and the emergence of drug resistant virus in a Phase 2b clinical study led to the discontinuation of GSK3532795. As part of the effort to further map the maturation inhibitor pharmacophore and provide additional structural options, the evaluation of alternates to the C-3 phenyl substituent in this chemotype was pursued. A cyclohexene carboxylic acid provided exceptional inhibition of wild-type, V370A and ΔV370 mutant viruses in addition to a suitable PK profile following oral dosing to rats. In addition, a novel spiro[3.3]hept-5-ene was designed to extend the carboxylic acid further from the triterpenoid core while reducing side chain flexibility compared to the other alkyl substituents. This modification was shown to closely emulate the C-3 benzoic acid moiety of GSK3532795 from both a potency and PK perspective, providing a non-traditional, sp3-rich bioisostere of benzene. Herein, we detail additional modifications to the C-3 position of the triterpenoid core that offer effective replacements for the benzoic acid of GSK3532795 and capture the interplay between these new C-3 elements and C-17 modifications that contribute to enhanced polymorph coverage. [ABSTRACT FROM AUTHOR]