Relation between saliva flow and flavor release from chewing gum

The objective of this study was to investigate whether or not parotid saliva flow is a significant determinant of flavor release from chewing gum. Cherry-flavored gum with 3 concentrations of citric acid (0.5, 1, and 2%) acting as a sialagogue was evaluated for sweetness and cherry flavor in duplicate by 13 subjects, using a computerized system for simultaneous time-intensity (TI) measurements and unilateral collection of parotid saliva. With increased acidity in the gum, maximum intensity of, and area under, the cherry flavor curve increased (p < 0.001), whereas total duration of sweetness decreased (p < 0.05). Large interindividual differences were found for parotid saliva flow in response to chewing gum. Mean unilateral parotid saliva flows in response to stimulation with water and gum with 0.5, 1, and 2% citric acid were 0.07, 0.30, 0.36, and 0.44 g/min, respectively. There was a significant positive correlation between saliva flow and time to reach maximum intensity of sweetness (p < 0.05) and of cherry flavor (p < 0.01), with "high-flow" subjects taking longer to reach maximum intensity than "low-flow" subjects for both attributes. We conclude that parotid saliva flow may affect the rate of flavor release, but not how much nor for how long flavor is released.     

Application of multidimensional scaling to the analysis of sensory evaluations of stimuli with known attribute structures.

Examined sensory perceptions of dimensionally simple stimuli composed of 1 or 2 objectively measurable attributes of flavor (sweet, sour) and color (red) using multidimensional scaling analysis. In 3 experiments with 20–30 19–36 yr old Ss each, high correlations were found between the objectively measurable physical characteristics of the stimuli and the perceptual spaces obtained by multidimensional scaling analysis of expressed gustatory and visual perceptions. Correlations were highest for stimuli sets containing single attributes detected by either gustation or vision and decreased when more complex sensory attributes were presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation between zinc content in saliva and blood in healthy human adults

Measurements were made of zinc levels in saliva, whole blood and plasma as well as copper levels in plasma by atomic absorption spectrophotometry. The mean zinc concentration (in ppm) was 0.478 (n = 136) in resting mixed saliva, 0.046 (n = 36) in parotid saliva, 6.41 (n = 145) in whole blood and 0.87 (n = 145) in plasma. The whole blood zinc levels were significantly lower in females than in males (P less than 0.001). Females and blood donors (males) had a significantly (P less than 0.001) higher Cu:Zn ratio than males (non-donors). It would thus appear, first, that the local effect of salivary zinc cannot be assessed simply from the concentration of zinc in stimulated parotid saliva since about nine-tenths of the zinc in resting mixed saliva is derived from other sources and, second, that the Cu:Zn in plasma is the most eligible variable for detecting sub-clinical Zn deficiency.     

Brainstem lesions and gustatory function: I. The role of the nucleus of the solitary tract during a brief intake test in rats.

Using an automated gustometer, licking behavior in rats was evaluated for a range of concentrations of appetitive and aversive stimuli in rats following electrolytic lesions in the rostral nucleus of the solitary tract (NST). Lesions of the NST flattened the concentration-response function for all gustatory stimuli. They attenuated the concentration-response function for MgCl?, QHCl, and NH?Cl by shifting it to the right by 0.5 log unit, attenuated the function for citric acid and Polycose by shifting it to the right by 1.5 log units, and fully eliminated the function for sucrose and NaCl. This failure to respond appropriately, however, was specific to gustatory stimuli because all rats reduced ingestive responding when presented with increasing concentrations of capsaicin, a trigeminal stimulus. Together, the data show that the NST is critical for responding appropriately to changes in intensity of a gustatory, but not a trigeminal, stimulus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improved large-scale isolation of breeder porcine islets: possibility of harvesting from nonheart-beating donor

Previous studies of the effect of carbonation on taste perception have suggested that it may be negligible, manifesting primarily in increases in the perceived intensity of weak salt and sour stimuli. Assuming CO2 solutions in the mouth stimulate only trigeminal nerve endings, this result is not altogether surprising; however, there are neurophysiological data indicating that CO2 stimulates gustatory as well as trigeminal fibers. In that case, carbonation might alter the quality profile of a stimulus without producing substantial changes in overall taste intensity--much as occurs when qualitatively different taste stimuli are mixed. To address this possibility, subjects were asked to rate the total taste intensity of moderate concentrations of stimuli representing each of the basic tastes and their binary combinations, with an without added carbonation. They then subdivided total taste intensity into the proportions of sweetness, saltiness, sourness, bitterness and 'other taste qualities' they perceived. The addition of carbonation produced only small increases in ratings of total taste intensity. However, rather dramatic alterations in the quality profiles of stimuli were observed, particularly for sweet and salty tastes. The nature of the interaction is consistent with a direct effect of carbonation/CO2 on the gustatory system, although the possibility that at least some of the observed effects reflect trigeminal-gustatory interactions cannot be ruled out.     

Salivary factors in children with recurrent parotitis. Part 2: Protein, albumin, amylase, IgA, lactoferrin lysozyme and kallikrein concentrations

The concentrations of total protein, albumin, amylase, IgA, lactoferrin, lysozyme and kallikrein in parotid saliva from 17 children with juvenile recurrent parotitis (JRP) in a non-active phase of disease and in healthy controls of the same number, sex and age were analysed after gustatory stimulation with 1%, 2% and 6% citric acid. There was a great individual variation in all analysed variables, especially in saliva from the diseased glands. Significantly raised levels of albumin, IgA, lactoferrin and kallikrein were found in the saliva from the JRP-children compared with the controls (p < 0.01-0.001), while total protein and alpha-amylase did not differ significantly. The sialo-chemical findings are discussed in the light of histological and bacteriological findings and support the hypothesis that the etiology of juvenile recurrent parotitis is a combination of congenital malformation of portions of the salivary ducts and a set-in infection.     

Occurrence of aflatoxins, fumonisin B1, and zearalenone in foods and feeds in Botswana

Sorghum and maize form the main dietary staple foods in Botswana. Other products such as peanuts, peanut butter, phane (an edible larval stage of an emperor moth Imbrasia belina Westwood), and pulses (cowpeas and beans) are also widely used as food and for the manufacture of feeds. These important food and feed commodities were analyzed for the presence of aflatoxins, fumonisin B1, and zearalenone. Aflatoxins were detected in 40% of the samples analyzed. The concentration of total aflatoxins ranged from 0.1 to 64 microg/kg. The mean concentration ranged from 0.3 microg/kg in sorghum to 23 microg/kg in peanut butter. Peanut butter samples were the most contaminated (71%). No aflatoxins were detected in maize. Fumonisin B1 was detected in 36% of the samples. Maize samples were the most contaminated (85% of the samples) with the concentration ranging from 20 to 1,270 microg/kg. No fumonisin B1 was detected in peanuts, phane, and beans. Zearalenone was only found in 2.6% of the samples analyzed at 40 microg/kg. Aflatoxins were the most common toxins detected in foods and feeds in Botswana. However, fumonisin B1 was more prevalent in maize than aflatoxins or zearalenone.     

Odorant responses in taste neurons of the rat NTS

In the experiment reported in this paper, 22 of 35 neurons in the gustatory NTS were found to respond to odorant as well as taste stimuli. This odorant response was apparently mediated by the ethmoid nerve and at least one other odorant-responsive system, possibly other nasal trigeminal afferents. These gustatory neurons responded to odorants, as they did to taste stimuli, in a manner consistent with an encoding of stimulus quality information. Thus at least some of the neurons of the gustatory NTS carry information concerning several of the senses involved in ingestion.     

Protein analysis of human von Ebner saliva and a method for its collection from the foliate papillae

The lingual serous glands of von Ebner are located close to the foliate and circumvallate papillae. Saliva secreted by these glands provides the immediate environment of the taste buds, and it has been hypothesized that it modulates taste perception. The purpose of this study was to develop a technique for collection of unstimulated and stimulated saliva from human von Ebner glands. Saliva was collected under resting conditions and after application of various gustatory stimuli (sweet, sour, salt, and bitter) by insertion of periostrips into the folds of the foliate papillae of healthy human volunteers. Stimulated saliva was also collected in glass microcapillaries or micropipettes. The flow-rates of unstimulated von Ebner saliva were 2.3 +/- 0.6 (S.E.) microL/min and 4.5 +/- 1.2 (S.E.) microL/min with 1% citric acid stimulation. The protein content was 2.5 +/- 0.5 (S.E.) mg/mL. The SDS gel electrophoretic profile of von Ebner saliva revealed two protein bands of Mr 18,000 that were identified on Western blots as von Ebner gland (VEG) proteins. Although lingual lipase activity was detected at very low levels by enzyme assay, this protein was not detected on Western blots. This collection technique should prove useful for analysis of specific functions associated with secretion from von Ebner glands.     

Gender differences in pain perception and patterns of cerebral activation during noxious heat stimulation in humans

The purpose of the present study was to determine whether gender differences exist in the forebrain cerebral activation patterns of the brain during pain perception. Accordingly, positron emission tomography (PET) with intravenous injection of H2(15)O was used to detect increases in regional cerebral blood flow (rCBF) in normal right-handed male and female subjects as they discriminated differences in the intensity of innocuous and noxious heat stimuli applied to the left forearm. Each subject was instructed in magnitude estimation based on a scale for which 0 indicated 'no heat sensation'; 7, 'just barely painful' and 10, 'just barely tolerable'. Thermal stimuli were 40 degrees C or 50 degrees C heat, applied with a thermode as repetitive 5-s contacts to the volar forearm. Both male and female subjects rated the 40 degrees C stimuli as warm but not painful and the 50 degrees C stimuli as painful but females rated the 50 degrees C stimuli as significantly more intense than did the males (P=0.0052). Both genders showed a bilateral activation of premotor cortex in addition to the activation of a number of contralateral structures, including the posterior insula, anterior cingulate cortex and the cerebellar vermis, during heat pain. However, females had significantly greater activation of the contralateral prefrontal cortex when compared to the males by direct image subtraction. Volume of interest comparison (t-statistic) also suggested greater activation of the contralateral insula and thalamus in the females (P < 0.05). These pain-related differences in brain activation may be attributed to gender, perceived pain intensity, or to both factors.     

Oral contraceptives alter circadian rhythm parameters of cortisol, melatonin, blood pressure, heart rate, skin blood flow, transepidermal water loss, and skin amino acids of healthy young women

This study investigated the usage consumption pattern and chemical composition of fermented foods consumed in 191 rural households (1030 individuals) in Emene. The result showed that fermented foods were widely used and consumed by most age groups (under 2 years to adults) because of poor socioeconomic status. Fermentation period varied with type of food and was mostly carried out as a means of detoxifying certain foods. Generally, fermented foods contributed substantially to the daily caloric (46.3 to 79.9% for males and 57.5 to 78% for females); calcium (33.8 to 63.5% for males and 48.3 to 55.4% for females); iron (34.4 to 58.6% for males and 47.4 to 74.6% for females); and thiamin (23 to 58.5% for males and 37.5 to 60% for females) intakes. The contributions of fermented foods to protein (10 to 40.7%) and ascorbic acid (1.9 to 18.7%) intakes were however, low. When compared with the FAO recommendations, the daily intakes of protein, calcium, riboflavin, niacin and ascorbic acid by the subjects were low due to large consumption of starchy root crops. Poor financial status was the most limiting factor to adequate nutrient intake. Such results point out the need for nutrition education related to improved methods of preparation and food selection.     

Gender differences in rowing performance and power with aging

Gender differences in experimental pain sensitivity have been widely investigated, and the results generally indicate that females exhibit greater sensitivity to noxious stimuli than males. However, results using thermal pain procedures have been inconsistent, with some studies reporting greater responses among females and other studies reporting no gender differences. The present study investigated gender differences in thermal pain perception using several different psychophysical procedures. Twenty-seven females and 22 males underwent thermal testing, including: determination of thermal pain threshold and tolerance, a thermal discrimination procedure, real-time magnitude estimates of heat pulses, and temporal summation of thermal pain. The results indicated lower thermal pain threshold and tolerance and greater temporal summation of thermal pain among females, but no gender differences in thermal discrimination or real-time magnitude estimates of discrete heat pulses. These findings suggest that gender differences in thermal pain perception may be more robust for sustained, temporally dynamic thermal stimuli with a strong C-fiber component.     

Randomly amplified polymorphic DNA (RAPD) for evaluating genetic relationships among varieties of guinea fowl

BACKGROUND: The aim of the present study was to investigate the existence of differences in dental status and in quantitative and qualitative salivary values between 100 patients with liver cirrhosis (LC) and a group of controls. MATERIAL AND METHODS: We analyzed the number of carious, missing and filled teeth. Also the unstimulated (UWS) and stimulated whole saliva flow rates (SWS) were determined, along with the stimulated parotid saliva flow rate (PSS) and the concentration in both UWS and SWS of sodium, potassium, total proteins and immunoglobulin A (IgA). RESULTS: A significantly higher number of carious and missing teeth was observed in the patients with cirrhosis (2.4 and 14.6, respectively) than in the control group (1.3 and 10.6, respectively), and a higher stimulated parotid flow rate with LC (0.64 and 0.44, respectively; p < 0.02) with a decrease in sodium and an increase in potassium, total proteins and IgA in patients with cirrhosis. In the LC group, caries were found to affect more teeth in those patients with alcohol-induced LC than in those with liver disease of other causes (3.9 and 1.7, respectively; p < 0.05), but in contrast, no differences were found in the saliva flow rate and the concentration in both UWS and SWS of sodium, potassium, total proteins and IgA. Finally, no relationship was observed between the dental status and functional hepatic tests. CONCLUSIONS: CH patients showed a worse dental status, a higher SPS rate and some electrolytes and proteins alterations.     

Contribution of endogenous opioids to gonadal hormones-induced temporomandibular joint antinociception.

The authors have recently demonstrated that the high serum estradiol level during the proestrus phase of the estrous cycle and that the administration of estradiol or progesterone in ovariectomized female and of testosterone in orchiectomized male rats significantly decrease formalin-induced temporomandibular joint (TMJ) nociception. In this study, the authors investigate the contribution of endogenous opioids to this antinociceptive effect of gonadal hormones in the TMJ formalin test. The opioid receptor antagonist naloxone was administrated either in the surrounding of the trigeminal sensory complex or in the TMJ region. The antinociceptive effect induced by endogenous estradiol in proestrus females and by exogenous estradiol in ovariectomized females was blocked by the administration of naloxone in the surrounding of the trigeminal sensory complex, but not in the TMJ region. The antinociceptive effect induced by the administration of progesterone in ovariectomized females and of testosterone in orchiectomized males was blocked by the administration of naloxone either in the surrounding of the trigeminal sensory complex or in the TMJ region. The authors conclude that central and peripheral opioid mechanisms mediate the antinociceptive effect of progesterone and testosterone, and central opioid mechanisms mediate the antinociceptive effect of estradiol. These findings suggest that the enhanced pain perception during low gonadal hormone periods in women and animals may be mediated by a decrease in endogenous opioid activity. This suggestion helps explain the higher severity of some pain conditions, such as temporomandibular dysfunctions in women than in men, that have no hormonal fluctuations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Galton's data a century later.

Analyzed F. Galton's (1885, 1892) data on the sensory, psychomotor, and physical attributes of 1,639 females and 4,849 males. The reliability of the measures, developmental trends in mean scores, correlations of the measures with age, correlations among measures, occupational differences in scores, and sibling correlations are described. Developmental trends during later childhood, adolescence, and early maturity are compared to those described in contemporary developmental psychological literature. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gustation and ingestive behavior in the rat.

Studied the contribution of taste to the quantitative control of intake and body weight in 15 male Wistar rats. Gustatory deafferentation was produced by combined bilateral section of the chorda tympani and glossopharyngeal nerves and the pharyngeal branch of the vagus nerve. The procedure did not affect the condition of the mouth, impair orientation to sensory stimuli, or severely disrupt the consummatory sequence. Nevertheless, deafferented Ss showed reduced responsiveness to food and water, elevated quinine HCl aversion thresholds, and impaired feeding efficiency. Food and water intake and body weight remained below control levels for at least 40–50 days postoperatively. Food intake deficits were not observed when Ss were offered ad lib pablum, a result suggesting that increased palatability could compensate for decreased gustatory input. The order of recovery of food intake through different diet types suggests a heightened responsiveness to taste stimuli. The effects of gustatory deafferentation are compared with those seen after section of trigeminal orosensory nerves, and the differential contributions of oral taste and oral touch are discussed. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Devices for saliva collection from the major salivary glands. Results in normal subjects

BACKGROUND: Collection of saliva produced by the major salivary glands may be accomplished either by cannulation of the glandular ducts or by the application of specific collecting devices to the emergence area of the glandular ducts. Those procedures are complex, slow, invasive and require skilled personnel. AIM: To report the design and application of a device to collect parotid saliva (snail collector) and another device to collect saliva from the submandibular/sublingual complex. MATERIAL AND METHODS: The saliva collection devices were tested in 40 healthy volunteers (20 male) aged 18 to 22 years old. Saliva was collected using conventional conditions, during 5 to 15 min. RESULTS: An average of 1 to 1.5 ml of saliva was collected in the 10-15 min period from both parotid and submandibular/sublingual glands. Flow rates from parotid glands were 80 microliters/min and 180 microliters/min from submandibular/sublingual glands. Parotid saliva had a protein and organic material concentration twice as high than saliva from submandibular/sublingual glands. The presence of human alpha-amylase duplet (Mr 55 kD and 58 kD) predominated in parotid saliva, whereas saliva from submandibular/sublingual glands had other molecular markers such as the lysozyme duplet (Mr 18.5 kD and 17 kD). CONCLUSIONS: The tested devices were easily applicable, comfortable and allowed the collection of both parotid saliva and submandibular/sublingual saliva from various subjects at once, under the supervision of a single professional.     

Progressive ratio performance in rats with gustatory thalamus lesions.

To determine whether damage of the gustatory thalamus (the parvicellular region of the ventroposteromedial nucleus) disrupts the perceived value of reinforcing stimuli, the performance of rats with bilateral, electrophysiologically guided, electrolytic lesions of the area was examined in Experiment 1 with a progressive-ratio schedule of reinforcement. Lesioned rats showed normal concentration-dependent changes in break point (an index of the amount of effort a subject will expend to obtain reinforcement) and in consummatory responding (licking) for the sucrose reward. In the reward comparison procedure of Experiment 2, however, the same lesioned rats failed to show morphine-induced suppression of alanine consumption. The results provide no support for the view that the thalamic taste area is involved in the perception of the absolute reinforcing value of gustatory stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Protein binding effects of salivary excretion of phenobarbital in dogs

The salivary excretion of phenobarbital was investigated by collecting parotid saliva (Pr) and mandibular-sublingual saliva (MS) separately after intravenous administration in beagle dogs. (1) The alterations in the proportions of saliva secreted by the different glands were produced by salivation stimulants such as citric acid, ascorbic acid, sodium chloride and sodium glutamate. (2) The phenobarbital concentrations in both Pr amd MS were lower than those in plasma. The drug concentrations in MS were significantly lower than in Pr with stimulus of 10% citric acid of 15% sodium chloride (p less than 0.05). There was a significant correlation between phenobarbital concentration in each saliva and plasma specimen ( p less than 0.05). (3) The stimulation with 10% citric acid produced higher saliva /plasma drug concentration ratios (S/P ratios: 0.923 +/- 0.175 for Pr, 0.633 +/- 0.073 for MS) than that with 15% sodium chloride (S/P ratios: 0.597 +/- 0.071 for Pr, 0.509 +/- 0.067 or MS). (4) The S/P ratios were hardly influenced by salivary flow rates, at least under the experimental conditions examined in this study. (5) The increased S/P ratios were observed with higher salivary pH and then the equation of Matin et al. 3) seemed to hold for the average values of salivary pH and S/P ratio. (6) The stimulation with 10% citric acid produced higher protein concentration in saliva and higher S/P ratio than that with 15% sodium chloride following alternate stimulations in the same dog.     

Hand preferences for a coordinated bimanual task in 110 chimpanzees (Pan troglodytes): Cross-sectional analysis.

Hand preference for a coordinated bimanual task was assessed in a sample of 110 chimpanzees (Pan troglodytes). Subjects were presented with opaque tubes, the inside of which was coated with peanut butter. The hand and finger used to extract the peanut butter was recorded in 2 test sessions. A population right-hand bias was found. Juvenile and adolescent subjects were less lateralized than adults. All subjects primarily used their index finger to extract peanut butter. Use of the index finger was higher in adults and adolescents compared with juveniles. The results suggest that coordinated bimanual tasks (a) elicit strong hand preferences at the individual level and (b) elicit population level right-handedness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)