Genetic analysis of chemosensory traits in human twins.

We explored genetic influences on the perception of taste and smell stimuli. Adult twins rated the chemosensory aspects of water, sucrose, sodium chloride, citric acid, ethanol, quinine hydrochloride, phenylthiocarbamide (PTC), potassium chloride, calcium chloride, cinnamon, androstenone, Galaxolide™, cilantro, and basil. For most traits, individual differences were stable over time and some traits were heritable (h(2) from 0.41 to 0.71). Subjects were genotyped for 44 single nucleotide polymorphisms within and near genes related to taste and smell. The results of these association analyses confirmed previous genotype-phenotype results for PTC, quinine, and androstenone. New associations were detected for ratings of basil and a bitter taste receptor gene, TAS2R60, and between cilantro and variants in three genes (TRPA1, GNAT3, and TAS2R50). The flavor of ethanol was related to variation within an olfactory receptor gene (OR7D4) and a gene encoding a subunit of the epithelial sodium channel (SCNN1D). Our study demonstrates that person-to-person differences in the taste and smell perception of simple foods and drinks are partially accounted for by genetic variation within chemosensory pathways.

Short to long term outcomes of 154 cemented total hip arthroplasties in ankylosing spondylitis.

BACKGROUND: Long-term outcome of Total Hip arthroplasty (THA) in Ankylosing Spondylitis (AS) remains unreported. Literature suggests a higher overall failure rate in ankylosing spondylitis as compared to osteoarthritis. Concern has been expressed regarding joint survival, given that recipients are generally young. The results of cemented THA in patients with ankylosing spondylitis were studied to determine the utility of THA for these patients. METHODS: Consecutive series of 96 patients (77 males (80%) and 19 females (20%)) with ankylosing spondylitis who underwent 154 cemented THAs at a tertiary referral orthopaedic centre between January 1990-September 2015 were retrospectively analyzed for clinical and radiological outcomes; 58 patients (60.4%) underwent bilateral surgery. RESULTS: Mean age at surgery was 48 years. Average follow up was 12.8 (2.1-24.8) years. 95% of the patients had a good or excellent post-operative outcome.Out of the total 154 hips operated on, 11% (17 hips) developed post-operative complications. Overall, 15 hips (9.7%) required a revision of the procedure, with the most common indication being aseptic loosening of the acetabulum. Average time to revision was 8.5 years (2-15). Survivorship analysis revealed probability of survival of both components at the end of 10 years, with revision due to any reason as the end point to be 92% (with 95% confidence intervals).21 hips (14%) developed heterotopic ossification post-operatively, of which 4 patients (2%) had clinically significant ossification (Brooker III or IV). CONCLUSION: This is one of the largest series of patients with ankylosing spondylitis with long term follow up available. Cemented THA in patients with ankylosing spondylitis provided consistently good and predictable long term results, with low rate of complications and revisions.

Conversion of Failed Hip Hemiarthroplasty to Low Friction Arthroplasty (LFA).

Purpose: We aimed to study clinical and radiological outcomes of conversion from hemiarthroplasty to Charnley hip replacement (CHR) with a particular concern over reported increased dislocation rate and literature review. Conversion of hip hemiarthroplasty to total hip replacement (THR) is a procedure reported to have high rates of complications. In the literature, there is no specific study on small head conversion. The purpose of this study was to evaluate the conversion of failed hip hemiarthroplasty to CHR with the use of modern implants. Methods: The study included 42 patients, who underwent the above procedure. The operations were carried out using a modern Charnley-type THR with a 22-mm diameter of femoral head and a trans-trochanteric approach. The mean follow-up was 75.7 months (range 25-171). Radiographs from the last follow up were evaluated for loosening and other reasons of failure. Clinical outcome was assessed using postoperative pain, function scores, complications and implant survivorship as well as radiological evaluation. Charnley's modified pain and mobility scoring system were used for clinical and Hodgkinson and Harris' criteria were used for radiological assessment. Results: Functionally, all of the patients showed improvement. Mean improvement in the pain level was by average of 2.4. On mobility assessment, 38 patients (90.4%) improved. Three patients (7.1%) had recurrent infections and three (4.8%) cases were treated with revision surgery and pseudarthrosis. Further complications occurred in 19.1%, not requiring operative treatment. On radiological evaluation, one (2.4%) case showed cup demarcation without bone loss, two (4.8%) cup migration, and one (2.4%) stem demarcation. Kaplan Meier survival analysis showed a survival of 90% at 96 months of follow up (95% CI (confidence interval), 60-90). Conclusion: Larger head might not be the answer to decrease the dislocation rate. Complication rates during revision of hip hemiarthroplasty to modern CHR with 22.225-mm head diameter were comparable to first-time THR revision despite having a smaller head.

Protective effects of bilberry (Vaccinium myrtillus L.) extract on KBrO3-induced kidney damage in mice.

Potassium bromate (KBrO3) is an oxidizing agent used as a food additive which causes kidney damage as a potent nephrotoxic agent, and the mechanism may be explained by the generation of oxygen free radicals. Our experiments showed that single intraperitoneal administration of 200 mg/kg KBrO3 could induce serious kidney damage, with an increase in serum blood urea nitrogen (BUN) and creatinine levels. Five-day oral administration of bilberry ( Vaccinium myrtillus L.) extract at 50, 100, and 200 mg/kg resulted in a reversal in serum BUN and creatinine to normal levels and decreased kidney malondialdehyde (MDA), nitric oxide (NO), and xanthine oxidase (XOD) levels. Also, bilberry extract improved oxygen radical absorbance capacity (ORAC) levels in kidney tissue, which showed that bilberry extract reduced the degree of oxidative stress and kidney damage induced by KBrO3. These findings demonstrate that the protective effect of bilberry extract is attributed to its free radical scavenging activity and lipid peroxidation inhibitory effect.

Oral Cooling and Carbonation Increase the Perception of Drinking and Thirst Quenching in Thirsty Adults.

Fluid ingestion is necessary for life, and thirst sensations are a prime motivator to drink. There is evidence of the influence of oropharyngeal stimulation on thirst and water intake in both animals and humans, but how those oral sensory cues impact thirst and ultimately the amount of liquid ingested is not well understood. We investigated which sensory trait(s) of a beverage influence the thirst quenching efficacy of ingested liquids and the perceived amount ingested. We deprived healthy individuals of liquid and food overnight (> 12 hours) to make them thirsty. After asking them to drink a fixed volume (400 mL) of an experimental beverage presenting one or two specific sensory traits, we determined the volume ingested of additional plain, 'still', room temperature water to assess their residual thirst and, by extension, the thirst-quenching properties of the experimental beverage. In a second study, participants were asked to drink the experimental beverages from an opaque container through a straw and estimate the volume ingested. We found that among several oro-sensory traits, the perceptions of coldness, induced either by cold water (thermally) or by l-menthol (chemically), and the feeling of oral carbonation, strongly enhance the thirst quenching properties of a beverage in water-deprived humans (additional water intake after the 400 ml experimental beverage was reduced by up to 50%). When blinded to the volume of liquid consumed, individual's estimation of ingested volume is increased (~22%) by perceived oral cold and carbonation, raising the idea that cold and perhaps CO2 induced-irritation sensations are included in how we normally encode water in the mouth and how we estimate the quantity of volume swallowed. These findings have implications for addressing inadequate hydration state in populations such as the elderly.

The effects of carbonated water upon gastric and cardiac activities and fullness in healthy young women.

Although previous reports suggested that carbonated water drinking was effective against gastrointestinal symptoms, there is little information about the effects of carbonated water on gastric and appetite sensation. We therefore investigated the effect of carbonated water on short-term fullness with respect to gastric and cardiac responses in 19 healthy young women. Each subject was tested on three separate days at approximately 9 a.m. after an overnight fast. Gastric motility, evaluated by electrogastrography (EGG) and heart rate (HR), was measured for 20 min in the fasting state and 40 min after ingestion of water. Preloads consisted of an equivalent amount (250 mL) of water (W) or carbonated water (CW) and no drinking (blank). Fullness scores were measured using visual analog scales. To determine gastric motility, we assessed the component of bradygastria (1-2 cycles/min [cpm]), normogastria (2-4 cpm), tachygastria (4-9 cpm), and dominant frequency of the EGG power spectrum. After ingestion of CW, significant increases in fullness scores were observed compared with W. All postprandial EGG powers were significantly greater than preprandial, but no group difference was found. However, a dominant frequency tended to shift toward a lower band after ingestion of W. A significantly higher HR was found following consumption of CW as opposed to W. Multiple regression analysis revealed that increased HR was a significant variable contributing to the variances in fullness after ingestion of CW at 40 min. Our data suggest that CW may induce a short-term, but significant, satiating effect through enhanced postprandial gastric and cardiac activities due possibly to the increased sympathetic activity and/or withdrawal of parasympathetic activity.

The effect of lutein supplementation on visual fatigue: a psychophysiological analysis.

We used psychophysiological technology to examine the effect of an oral supplement, a combination of lutein, zeaxanthin and blackcurrant extract (LUT), on visual fatigue, within the context of a randomized, double-blind, placebo-controlled cross-over trial. The LUT supplement and placebo samples were randomly assigned to thirteen participants, who took the samples for two LUT (and vice versa) for another 2 week. Each participant completed visual proof reading tasks for 2h during each of four testing sessions. Saccade tests were administered before and after the proof reading task, during which the participants moved their eyes back and forth between two targets positioned in the center of two checkerboards. We recorded EEG, EOG, heart rate, and facial muscle potential/performance during the saccade tests. Blood pressure was measured and subjective fatigue and stress scores were collected before and after the proof reading task. We averaged EEG starting at saccade offset in order to analyze eye fixation related potentials (EFRP). Our results suggested that the proof reading task induced visual fatigue. An analysis of EFRP and other psychophysiological data revealed significant differences between the LUT and placebo conditions. These results suggest that supplementation with LUT could help to reduce symptoms of visual fatigue.

Protective effects of bilberry (Vaccinium myrtillus L.) extract on restraint stress-induced liver damage in mice.

Our experiments showed that 18 h restraint stress could induce serious liver damage, with an increase in plasma alanine aminotransferase (ALT) level (107.68 +/- 3.19 U/L vs 18.08 +/- 1.46 U/L). Meanwhile, we observed increased malondialdehyde (MDA) levels and lowered oxygen radical absorbance capacity (ORAC) values in plasma and liver of restraint mice compared with starved mice. Bilberry extract (containing 42.04% anthocyanins) was oral administrated to mice at 50, 100, and 200 mg/(kg x day) for five days, which remarkably decreased plasma ALT level to 17.23 +/- 2.49 U/L at the dose of 200 mg/(kg x day) and thus alleviated stress-induced liver damage. In addition, bilberry extracts increased glutathione (GSH) and vitamin C levels and significantly decreased MDA and nitric oxide (NO) levels in the liver tissues. These results suggest that bilberry extract plays an important role in protecting against restraint stress-induced liver damage by both scavenging free radicals activity and lipid peroxidation inhibitory effect. This study showed the beneficial health effects of bilberry extract through its antioxidative action.

Cortical representation of taste-modifying action of miracle fruit in humans.

Red berries of a tropical plant called miracle fruit, Richadella dulcifica, reduce the sour and aversive taste of acids and add sweet and palatable taste. To elucidate the brain mechanism of this unique action of miracle fruit, we recorded taste-elicited magnetic fields of the human cerebral cortex. The initial taste responses were localized in the fronto-parietal opercular/insular cortex reported as the primary taste area. The mean latency of the response to citric acid after chewing miracle fruit was essentially the same as that for sucrose and was 250-300 ms longer than that for citric acid. Since it is known that stimulation with acids after the action of miracle fruit induces both sweetness and sourness responses in the primate taste nerves, the present results suggest that the sourness component of citric acid is greatly diminished at the level of subcortical relays, and mostly sweetness information reaches the cortical primary taste area. We propose the idea that the qualitative aspect of taste is processed in the primary taste area and the affective aspect is represented by the pattern of activation among the different cortical areas.

Effects of repeated exposure and health-related information on hedonic evaluation and acceptance of a bitter beverage.

The influence of exposure and information on sensory evaluation and acceptance of bitter flavor was assessed. Following sensory testing in the laboratory, subjects consumed a commercially-available bittersweet beverage once daily for 7days in a setting of their choosing, then returned to the laboratory for post-exposure tests. Hedonic ratings for the beverage increased by 68%, whereas ratings for control stimuli sampled only in the laboratory did not change. Following exposure, relationships of hedonic ratings with intensity and familiarity varied according to the context in which evaluations were made: hedonic ratings were correlated with intensity in a familiar setting and with familiarity in an unfamiliar setting. Health-related information had no effect on perceptual changes that accompanied exposure, but did tend to increase a behavioral measure of acceptability, suggesting that information may have a greater effect on behavior than on hedonics. Together, the data suggest that repeated exposure can enhance hedonic evaluation of a bittersweet beverage, perhaps through a learned association of flavor with post-ingestive consequences. Context may mediate this effect and studies addressing the influence of information on bitter food acceptance should include measures of consumption and evaluate information strategies, as bitter foods may be particularly resistant to cognitively-based appeals.