Effect of guaifenesin on cough reflex sensitivity

BACKGROUND: Guaifenesin, a commonly used agent for the treatment of cough, is termed an expectorant since it is believed to alleviate cough discomfort by increasing sputum volume and decreasing its viscosity, thereby promoting effective cough. Despite its common usage, relatively few studies, yielding contrasting results, have been performed to investigate the action and efficacy of guaifenesin. STUDY OBJECTIVES: To evaluate the effect of guaifenesin on cough reflex sensitivity. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: Academic medical center. PARTICIPANTS: Fourteen subjects with acute viral upper respiratory tract infection (URI) and 14 healthy volunteers. INTERVENTIONS: On 2 separate days, subjects underwent capsaicin cough challenge 1 to 2 h after receiving a single, 400-mg dose (capsules) of guaifenesin or matched placebo. Measurements and results: The concentration of capsaicin inducing five or more coughs (C(5)) was determined. Among subjects with URI, mean (+/- SEM) log C(5) after guaifenesin and placebo were 0.92 +/- 0.17 and 0.66 +/- 0.14, respectively (p = 0.028). No effect on cough sensitivity was observed in healthy volunteers. CONCLUSIONS: Our results demonstrate that guaifenesin inhibits cough reflex sensitivity in subjects with URI, whose cough receptors are transiently hypersensitive, but not in healthy volunteers. Possible mechanisms include a central antitussive effect, or a peripheral effect by increased sputum volume serving as a barrier shielding cough receptors within the respiratory epithelium from the tussive stimulus.     

Measuring nursing activities using an ecological momentary assessment method

The ecological momentary assessment method proved to be an effective and efficient method for conducting a study to assess nursing activities across a number of hospital settings and geographic distances. Nurse administrators and outcomes researchers who are seeking to measure and assess nurse activities should consider using this approach.     

Neither acute nor chronic exposure to a naturalistic (predator) stressor influences the interleukin-1beta system, tumor necrosis factor-alpha, transforming growth factor-beta1, and neuropeptide mRNAs in specific brain regions

Physical (neurogenic) stressors may influence immune functioning and interleukin-1beta (IL-1beta) mRNA levels within several brain regions. The present study assessed the effects of an acute or repeated naturalistic, psychogenic stressor (predator exposure) on brain cytokine and neuropeptide mRNAs. Acute predator (ferret) exposure induced stress-like behavioral effects, including elicitation of a startle response and reduced exploratory behaviors; these responses diminished after 30 sessions. Moreover, acute and repeated predator exposure, like acute restraint stress, increased plasma corticosterone levels measured 5 min later, but not 2 h after stressor exposure. In contrast, none of the stressors used influenced IL-1beta, IL-1 receptor antagonist, IL-1 receptor type I, IL-1 receptor accessory proteins I and II, or tumor necrosis factor-alpha mRNA levels in the prefrontal cortex, amygdala, hippocampus, or hypothalamus. Likewise, there were no stressor effects on transforming growth factor-beta1, neuropeptide Y, glycoprotein 130, or leptin receptor mRNAs in brain regions. Thus, the naturalistic/psychogenic stressor used does not affect any of the brain cytokine component mRNAs studied. It is suggested that this type of stressor activates homeostatic mechanisms (e.g., glucocorticoid release), which act to preclude brain cytokine alterations that would otherwise favor neuroinflammatory/neuroimmunological responses and the consequent increase of brain sensitivity to neurotoxic and neurodegenerative processes.     

Vitamin K-independent warfarin resistance after concurrent administration of warfarin and continuous enteral nutrition

STUDY OBJECTIVE: To assess the influence of withholding continuous enteral nutrition for 1 hour before and after warfarin administration compared with the coadministration of warfarin with continuous enteral nutrition on changes in international normalized ratios (INRs). DESIGN: Retrospective, crossover case series. SETTING: Intensive care units of a university-affiliated medical center. PATIENTS: Six adults who required nutritional support for at least the first 10 consecutive days of warfarin therapy; during that 10-day period, they had a period of at least 3 consecutive days during which the enteral feeding was withheld for 1 hour before and after warfarin administration, and had a period of at least 3 consecutive days when feedings were not withheld during warfarin administration. Patients with advanced liver disease and those who received therapies, during the observation period, that significantly alter warfarin metabolism were omitted from the study. MEASUREMENTS AND MAIN RESULTS: The change in INR during the 3-day observation period when feedings were withheld for 1 hour before and after warfarin administration was significantly different versus the change in INR during coadministration of warfarin with continuous feeding (mean +/- SD 0.74 +/- 0.66 vs -0.13 +/- 0.81, p < or = 0.05). This difference in INR response occurred despite the administration of similar dosages of warfarin (5.6 +/- 2.1 vs 5.7 +/- 2.1 mg/day, p>0.05). Also noted was a clinically irrelevant, but statistically significant, difference in vitamin K intake between treatment periods (77 +/- 36 mug/day when feedings were withheld vs 102 +/- 28 microg/day when feedings were not withheld, p < or = 0.05). CONCLUSION: Continuous enteral nutrition should be withheld for 1 hour before and after warfarin administration to prevent enteral nutrition-associated warfarin resistance.     

Investigating the fate of saxitoxins in biologically active water treatment plant filters

The saxitoxins are potent neurotoxins, which can be produced by freshwater cyanobacteria. This study assessed the fate of five saxitoxins variants through biologically active laboratory filters containing media sourced from the filters beds of two water treatment plants (WTPs). Decreases in the concentration of the less toxic variants coincided with increases in the concentrations of the more toxic variants through the filters containing anthracite sourced from two different WTPs. No changes in toxin concentrations were evident through parallel filters containing sand. The results strongly suggest that organisms within the biofilm of the anthracite filters possessed the ability to biotransform the saxitoxins variants, which has important implications for drinking water treatment, particularly since this has the potential to increase the toxicity of the filtered water.     

Alvimopan

Alvimopan, a trans-3,4-dimethyl-4-(3-hydroxy-phenyl) piperidine, is a selective, peripherally acting micro-opioid receptor antagonist that is available for short-term use in hospitalized patients who have undergone bowel resection. The efficacy of alvimopan in the management of postoperative ileus has been evaluated in five phase III trials; four conducted in North America and one conducted in Europe/Australasia. Patients who had undergone partial large or small bowel resection surgery with primary anastomosis were randomized to receive alvimopan 12 mg or placebo as a single oral pre-operative dose followed by twice-daily administration for up to 7 days postoperatively. In the five phase III trials, alvimopan was significantly more effective than placebo in reducing the time to recovery of upper and lower gastrointestinal (GI) function, as assessed using a two-component endpoint (GI2) comprising time to tolerance of solid food and first bowel movement. The mean time to reach the GI2 endpoint was 11-26 hours sooner with alvimopan than with placebo. In the phase III trials conducted in North America, the time to writing the hospital discharge order was 13-21 hours sooner with alvimopan than with placebo. Alvimopan did not reduce opioid-induced analgesia and/or increase the amount of opioids administered postoperatively. Short-term alvimopan was generally well tolerated in adults undergoing bowel resection.     

Conceiving Time? Women who do or do not conceive

This article explores the importance of time for an understanding of women's experiences of reproductive identity. In order to do this we draw on data from two separate qualitative research projects. The first project is concerned with the experiences of conception, pregnancy, childbirth and early motherhood in primagravidae, whilst the second focuses on the experiences of individuals (especially women) who defined themselves (at the time of the fieldwork, or some time previously) as 'involuntarily childless' and/or 'infertile'. These two areas are usually treated as separate; this article, however, explores similarities between them in terms of time and medicalisation. Our central concern, then, is with exploring the similarities of experience for women who do or do not conceive.