Pre-existent expectancy effects in the relationship between caffeine and performance

The present study investigated the impact of pre-existent expectancy regarding the effects of the caffeine load of a drink and the perception of the caffeine content on subjective mood and vigilance performance. Caffeine deprived participants (N=25) were tested in four conditions (within subjects design), using a 2 × 2 design, with caffeine load and information regarding the caffeine content of the drink. In two sessions, they were given caffeinated coffee and in two were given decaffeinated coffee. Within these two conditions, on one occasion they were given accurate information about the drink and on the other they were given inaccurate information about the drink. Mood and vigilance performance were assessed post ingestion. Caffeine was found to enhance performance, but only when participants were accurately told they were receiving it. When decaffeinated coffee was given, performance was poorer, irrespective of expectancy. However, when caffeine was given, but participants were told it was decaffeinated coffee, performance was as poor as when no caffeine had been administered. There were no easily interpretable effects on mood. The pharmacological effects of caffeine appear to act synergistically with expectancy. © 2010.

Investigating the effects of caffeine on executive functions using traditional Stroop and a new ecologically-valid virtual reality task, the Jansari assessment of Executive Functions (JEF©)

Objective: Caffeine has been shown to have effects on certain areas of cognition, but in executive functioning the research is limited and also inconsistent. One reason could be the need for a more sensitive measure to detect the effects of caffeine on executive function. This study used a new non-immersive virtual reality assessment of executive functions known as JEF© (the Jansari Assessment of Executive Function) alongside the ‘classic’ Stroop Colour- Word task to assess the effects of a normal dose of caffeinated coffee on executive function. Method: Using a double-blind, counterbalanced within participants procedure 43 participants were administered either a caffeinated or decaffeinated coffee and completed the ‘JEF©’ and Stroop tasks, as well as a subjective mood scale and blood pressure pre- and post condition on two separate occasions a week apart. JEF© yields measures for eight separate aspects of executive functions, in addition to a total average score. Results: Findings indicate that performance was significantly improved on the planning, creative thinking, event-, time- and action-based prospective memory, as well as total JEF© score following caffeinated coffee relative to the decaffeinated coffee. The caffeinated beverage significantly decreased reaction times on the Stroop task, but there was no effect on Stroop interference. Conclusion: The results provide further support for the effects of a caffeinated beverage on cognitive functioning. In particular, it has demonstrated the ability of JEF© to detect the effects of caffeine across a number of executive functioning constructs, which weren’t shown in the Stroop task, suggesting executive functioning improvements as a result of a ‘typical’ dose of caffeine may only be detected by the use of more real-world, ecologically valid tasks.

A combination of amino acids and caffeine enhances sprint running capacity in a hot, hypoxic environment.

Caffeine Intake and its Association with Disease Progression, Sleep Quality and Anxiety Symptoms and Nutritional Alterations in People Living with HIV in the Miami Adult Studies on HIV Cohort

Miami-Dade County has approximately 27,000 people living with HIV (PLWH), and the highest HIV incidence in the nation. PLWH have reported several types of sleep disturbances. Caffeine is an anorexic and lipolytic stimulant that may adversely affect sleep patterns, dietary intakes and body composition. High caffeine consumption (>250 mg. per day or the equivalent of >4 cups of brewed coffee) may also affect general functionality, adherence to antiretroviral treatment (ART) and HIV care. This study assess the relationship of high caffeine intake with markers of disease progression, sleep quality, insomnia, anxiety, nutritional intakes and body composition. A convenience sample of 130 PLWH on stable ART were recruited from the Miami Adult Studies on HIV (MASH) cohort, and followed for three months. After consenting, questionnaires on Modified Caffeine Consumption (MCCQ), Pittsburg Insomnia Rating Scale (PIRS), Pittsburg Sleep Quality Index (PSQI), Generalized Anxiety Disorder-7 (GAD-7), socio-demographics, drug and medication use were completed. CD4 count, HIV viral load, anthropometries, and body composition measures were obtained. Mean age was 47.89±6.37 years, 60.8% were male and 75.4% were African-Americans. Mean caffeine intake at baseline was 337.63 ± 304.97 mg/day (Range: 0-1498 mg/day) and did not change significantly at 3 months. In linear regression, high caffeine consumption was associated with higher CD4 cell count (β=1.532, P=0.049), lower HIV viral load (β=-1.067, P=0.048), higher global PIRS (β=1.776, P=0.046), global PSQI (β=2.587, P=0.038), and GAD-7 scores (β=1.674, P=0.027), and with lower fat mass (β=-0.994, P=0.042), energy intakes (β=-1.643, P=0.042) and fat consumption (β=-1.902, P=0.044), adjusting for relevant socioeconomic and disease progression variables. Over three months, these associations remained significant. The association of high caffeine with lower BMI weakened when excluding users of other anorexic and stimulant drugs such as cocaine and methamphetamine, suggesting that caffeine in combination, but not alone, may worsen their action. In summary, high caffeine consumption was associated with better measures of disease progression; but was also detrimental on sleep quality, nutritional intakes, BMI and body composition and associated with insomnia and anxiety. Large scale studies for longer time are needed to elucidate the contribution of caffeine to the well-being of PLWH.

A longitudinal study of the relationship between lifestyle and mental health among midlife and older women in Australia : findings from the Healthy Aging of Women Study

We investigated the temporal relationship between lifestyle and mental health among 564 midlife women. The mental health measured included anxiety, depression, and mental well-being; the lifestyle measures included body mass index (BMI), exercise, smoking, alcohol use, and caffeine consumption. We found that BMI was positively related with mental well-being (r = .316, p = .009); smokers had lower mental well-being than nonsmokers (β = 6.725, p = .006), and noncaffeine drinkers had higher mental well-being (β = 5, p = .023). Past alcohol-drinkers had less anxiety than nondrinkers (β = 1.135, p = .04). Therefore, lifestyle is predictive of mental health among midlife and older women.

The circadian response of intrinsically photosensitive retinal ganglion cells

Intrinsically photosensitive retinal ganglion cells (ipRGC) signal environmental light level to the central circadian clock and contribute to the pupil light reflex. It is unknown if ipRGC activity is subject to extrinsic (central) or intrinsic (retinal) network-mediated circadian modulation during light entrainment and phase shifting. Eleven younger persons (18–30 years) with no ophthalmological, medical or sleep disorders participated. The activity of the inner (ipRGC) and outer retina (cone photoreceptors) was assessed hourly using the pupil light reflex during a 24 h period of constant environmental illumination (10 lux). Exogenous circadian cues of activity, sleep, posture, caffeine, ambient temperature, caloric intake and ambient illumination were controlled. Dim-light melatonin onset (DLMO) was determined from salivary melatonin assay at hourly intervals, and participant melatonin onset values were set to 14 h to adjust clock time to circadian time. Here we demonstrate in humans that the ipRGC controlled post-illumination pupil response has a circadian rhythm independent of external light cues. This circadian variation precedes melatonin onset and the minimum ipRGC driven pupil response occurs post melatonin onset. Outer retinal photoreceptor contributions to the inner retinal ipRGC driven post-illumination pupil response also show circadian variation whereas direct outer retinal cone inputs to the pupil light reflex do not, indicating that intrinsically photosensitive (melanopsin) retinal ganglion cells mediate this circadian variation.

Non-invasive, quantitative analysis of drug mixtures in containers using spatially offset Raman spectroscopy (SORS) and multivariate statistical analysis

In this paper, spatially offset Raman spectroscopy (SORS) is demonstrated for non-invasively investigating the composition of drug mixtures inside an opaque plastic container. The mixtures consisted of three components including a target drug (acetaminophen or phenylephrine hydrochloride) and two diluents (glucose and caffeine). The target drug concentrations ranged from 5% to 100%. After conducting SORS analysis to ascertain the Raman spectra of the concealed mixtures, principal component analysis (PCA) was performed on the SORS spectra to reveal trends within the data. Partial least squares (PLS) regression was used to construct models that predicted the concentration of each target drug, in the presence of the other two diluents. The PLS models were able to predict the concentration of acetaminophen in the validation samples with a root-mean-square error of prediction (RMSEP) of 3.8% and the concentration of phenylephrine hydrochloride with an RMSEP of 4.6%. This work demonstrates the potential of SORS, used in conjunction with multivariate statistical techniques, to perform non-invasive, quantitative analysis on mixtures inside opaque containers. This has applications for pharmaceutical analysis, such as monitoring the degradation of pharmaceutical products on the shelf, in forensic investigations of counterfeit drugs, and for the analysis of illicit drug mixtures which may contain multiple components.

Effects of acute multi-nutrient supplementation on rugby union match performance and recovery

Aim: To determine the effects of an acute multi-nutrient supplement on physiological, performance and recovery responses to intermittent-sprint running and muscular damage during rugby union matches. Methods: Using a randomised, double-blind, cross-over design, twelve male rugby union players ingested either 75 g of a comprehensive multi-nutrient supplement (SUPP), [Musashi] or 1 g of a taste and carbohydrate matched placebo (PL) for 5 days pre-competition. Competitive rugby union game running performance was then measured using 1 Hz GPS data (SPI10, SPI elite, GPSports), in addition to associated blood draws, vertical jump assessments and ratings of perceived muscular soreness (MS) pre, immediately post and 24 h post-competition. Baseline (BL) GPS data was collected during six competition rounds preceding data collection. Results: No significant differences were observed between supplement conditions for all game running, vertical jump, and ratings of perceived muscular soreness. However, effect size analysis indicated SUPP ingestion increased 1st half very high intensity running (VHIR) mean speed (d = 0.93) and 2nd half relative distance (m/min) (d = 0.97). Further, moderate increases in 2nd half VHIR distance (d = 0.73), VHIR m/min (d = 0.70) and VHIR mean speed (d = 0.56) in SUPP condition were also apparent. Moreover, SUPP demonstrated significant increases in 2nd half dist m/min, total game dist m/min and total game HIR m/min compared with BL data (P < 0.05). Further, large ES increases in VHIR time (d = 0.88) and moderate increases in 2nd half HIR m/min (d = 0.65) and 2nd half VHIR m/min (d = 0.74) were observed between SUPP and BL. Post-game aspartate aminotransferase (AST) (d = 1.16) and creatine kinase (CK) (d = 0.97) measures demonstrated increased ES values with SUPP, while AST and CK values correlated with 2nd half VHIR distance (r = −0.71 and r = −0.76 respectively). Elevated c-reactive protein (CRP) was observed post-game in both conditions, however was significantly blunted with SUPP (P = 0.05). Additionally, pre-game (d = 0.98) and post-game (d = 0.96) increases in cortisol (CORT) were apparent with SUPP. No differences were apparent between conditions for pH, lactate, glucose, HCO3, vertical jump assessments and MS (P > 0.05). Conclusion: These findings suggest SUPP may assist in the maintenance of VHIR speeds and distances covered during rugby union games, possibly via the buffering qualities of SUPP ingredients (i.e. caffeine, creatine, bicarbonate). While the mechanisms for these findings are unclear, the similar pH between conditions despite additional VHIR during SUPP may support this conclusion. Finally, correlations between increased work completed at very high intensities and muscular degradation in SUPP conditions, may mask any anti-catabolic properties of supplementation.

Can a community pharmacy sleep assessment tool aid the identification of patients at risk of sleep disorders in the community : a pilot study

Background: When experiencing sleep problems for the first time, consumers may often approach community pharmacists for advice as they are easily accessible health care professionals in the community. In Australian community pharmacies there are no specific tools available for use by pharmacists to assist with the assessment and handling of consumers with sleep enquiries. Objective: To assess the feasibility of improving the detection of sleep disorders within the community through the pilot of a newly developed Community Pharmacy Sleep Assessment Tool (COP-SAT). Method: The COP-SAT was designed to incorporate elements from a number of existing, standardized, and validated clinical screening measures. The COP-SAT was trialed in four Australian community pharmacies over a 4-week period. Key findings: A total of 241 community pharmacy consumers were assessed using the COP-SAT. A total of 74 (30.7%) were assessed as being at risk of insomnia, 26 (10.7%) were at risk of daytime sleepiness, 19 (7.9%) were at risk of obstructive sleep apnea, and 121 (50.2%) were regular snorers. A total of 116 (48.1%) participants indicated that they consume caffeine before bedtime, of which 55 (47%) had associated symptoms of sleep onset insomnia. Moreover, 85 (35%) consumed alcohol before bedtime, of which 50 (58%) experienced fragmented sleep, 50 (58%) were regular snorers, and nine (10.6%) had apnea symptoms. The COP-SAT was feasible in the community pharmacy setting. The prevalence of sleep disorders in the sampled population was high, but generally consistent with previous studies on the general population. Conclusion: A large proportion of participants reported sleep disorder symptoms, and a link was found between the consumption of alcohol and caffeine substances at bedtime and associated symptoms. While larger studies are needed to assess the clinical properties of the tool, the results of this feasibility study have demonstrated that the COP-SAT may be a practical tool for the identification of patients at risk of developing sleep disorders in the community.

Countermeasures to driver sleepiness : is the message getting through?

The most effective countermeasures to driver sleepiness (caffeine and a nap, ideally in combination) are not the most popular choice for UK drivers. Groups susceptible to driver sleepiness (OSA patients and truck drivers) do not favour effective countermeasures to driver sleepiness. Prior experience of driver sleepiness does not promote an effective choice of countermeasure.

Management of over-the-counter insomnia complaints in Australian community pharmacies: A standardized patient study

Objective To evaluate the current management of over-the-counter (OTC) insomnia complaints in Australian community pharmacies using standardized patient methodology. Methods Trained standardized patients visited a sample of 100 randomly selected South East Queensland community pharmacies in June 2011. The standardized patients enacted two OTC insomnia scenarios: a direct product request (DPR) (n = 50) and a symptom-based request (SBR) (n = 50). Results of the interactions were documented immediately after each visit and evaluated using the Pharmaceutical Society of Australia's WHAT STOP GO protocol as a standard comparison. Key findings Of all DPRs, 30% were handled entirely by the pharmacist, 70% of staff enquired about specific symptoms and 28% investigated the cause of insomnia. No staff investigated the frequency of product use. The DPR scenario resulted in a 92% supply of the requested doxylamine product (Restavit). In the SBR scenario, 18% of requests were handled entirely by the pharmacist, 58% of staff enquired about specific symptoms and 44% investigated the cause of insomnia. Staff recommended medicated products (38%), or herbal (78%) or non-drug techniques (18%). Investigation into smoking and alcohol intake was not undertaken in DPR or SBR interactions, while questioning on caffeine intake was undertaken in 2 and 14% of cases respectively. There were no significant differences found in the handling of sleep requests by pharmacists compared to pharmacy assistants. Conclusion The standardized patient methodology was a successful way to assess the community pharmacy counselling provided with OTC sleep requests and suboptimal staff responses were found when compared with recommended practice standards.

Comprehensive Addictive Behaviors and Disorders, Volume 1 : Principles of Addiction

"Principles of Addiction provides a solid understanding of the definitional and diagnostic differences between use, abuse, and disorder. It describes in great detail the characteristics of these syndromes and various etiological models. The book's three main sections examine the nature of addiction, including epidemiology, symptoms, and course; alcohol and drug use among adolescents and college students; and detailed descriptions of a wide variety of addictive behaviors and disorders, encompassing not only drugs and alcohol, but caffeine, food, gambling, exercise, sex, work, social networking, and many other areas. This volume is especially important in providing a basic introduction to the field as well as an in-depth review of our current understanding of the nature and process of addictive behaviors. Principles of Addiction is one of three volumes comprising the 2,500-page series, Comprehensive Addictive Behaviors and Disorders. This series provides the most complete collection of current knowledge on addictive behaviors and disorders to date. In short, it is the definitive reference work on addictions."--publisher website

Label-free SERS for natural product provenance

Introduction Natural product provenance is important in the food, beverage and pharmaceutical industries, for consumer confidence and with health implications. Raman spectroscopy has powerful molecular fingerprint abilities. Surface Enhanced Raman Spectroscopy’s (SERS) sharp peaks allow distinction between minimally different molecules, so it should be suitable for this purpose. Methods Naturally caffeinated beverages with Guarana extract, coffee and Red Bull energy drink as a synthetic caffeinated beverage for comparison (20 µL ea.) were reacted 1:1 with Gold nanoparticles functionalised with anti-caffeine antibody (ab15221) (10 minutes), air dried and analysed in a micro-Raman instrument. The spectral data was processed using Principle Component Analysis (PCA). Results The PCA showed Guarana sourced caffeine varied significantly from synthetic caffeine (Red Bull) on component 1 (containing 76.4% of the variance in the data). See figure 1. The coffee containing beverages, and in particular Robert Timms (instant coffee) were very similar on component 1, but the barista espresso showed minor variance on component 1. Both coffee sourced caffeine samples varied with red Bull on component 2, (20% of variance). ************************************************************ Figure 1 PCA comparing a naturally caffeinated beverage containing Guarana with coffee. ************************************************************ Discussion PCA is an unsupervised multivariate statistical method that determines patterns within data. Figure 1 shows Caffeine in Guarana is notably different to synthetic caffeine. Other researchers have revealed that caffeine in Guarana plants is complexed with tannins. Naturally sourced/ lightly processed caffeine (Monster Energy, Espresso) are more inherently different than synthetic (Red Bull) /highly processed (Robert Timms) caffeine, in figure 1, which is consistent with this finding and demonstrates this technique’s applicability. Guarana provenance is important because it is still largely hand produced and its demand is escalating with recognition of its benefits. This could be a powerful technique for Guarana provenance, and may extend to other industries where provenance / authentication are required, e.g. the wine or natural pharmaceuticals industries.

A novel identification method for ultra trace detection of biomolecules using functionalised Surface Enhanced Raman Spectroscopy (SERS)

This thesis developed a new method for measuring extremely low amounts of organic and biological molecules, using Surface enhanced Raman Spectroscopy. This method has many potential applications, e.g. medical diagnosis, public health, food provenance, antidoping, forensics and homeland security. The method development used caffeine as the small molecule example, and erythropoietin (EPO) as the large molecule. This method is much more sensitive and specific than currently used methods; rapid, simple and cost effective. The method can be used to detect target molecules in beverages and biological fluids without the usual preparation steps.

Ultra sensitive label free surface enhanced Raman spectroscopy method for the detection of biomolecules

We present a proof of concept for a novel nanosensor for the detection of ultra-trace amounts of bio-active molecules in complex matrices. The nanosensor is comprised of gold nanoparticles with an ultra-thin silica shell and antibody surface attachment, which allows for the immobilization and direct detection of bio-active molecules by surface enhanced Raman spectroscopy (SERS) without requiring a Raman label. The ultra-thin passive layer (~1.3 nm thickness) prevents competing molecules from binding non-selectively to the gold surface without compromising the signal enhancement. The antibodies attached on the surface of the nanoparticles selectively bind to the target molecule with high affinity. The interaction between the nanosensor and the target analyte result in conformational rearrangements of the antibody binding sites, leading to significant changes in the surface enhanced Raman spectra of the nanoparticles when compared to the spectra of the un-reacted nanoparticles. Nanosensors of this design targeting the bio-active compounds erythropoietin and caffeine were able to detect ultra-trace amounts the analyte to the lower quantification limits of 3.5×10−13 M and 1×10−9 M, respectively.