Biomedical subjects

W S Cain

Publications and source records attributed to W S Cain.

At least 37 records · Page 2Linked to original sources

PubMed1998

Etiology and retrieval of retained central venous catheter fragments within the heart and great vessels of infants and children.

BACKGROUND: The use of centrally positioned venous catheters plays an indispensable role in the care of infants and children. METHODS: Since 1992 the authors have seen nine patients who experienced fragmentation and migration of catheter fragments into the central circulation. The patients ranged in age from 6 days to 15 years. RESULTS: Sites of migration included pulmonary artery (five patients), superior vena cava (two patients), hepatic vein and innominate vein (one patient). The elapsed time from recognition of retained catheter fragments until retrieval ranged from a few hours to 6 weeks. CONCLUSION: All retained fragments were successfully removed during cardiac catheterization without complications.

Adolescent↗

PubMed1998

Trigeminal and olfactory chemosensory impact of selected terpenes.

In Experiment 1, four normosmics and four anosmics (three congenital, one idiopathic) provided odor and nasal pungency thresholds, respectively, for the following terpenes: delta3-carene, p-cymene, linalool, 1.8-cineole, and geraniol, plus the structurally related compound cumene. Additionally, all subjects provided nasal localization (i.e., right/left) and eye irritation thresholis. Trigeminally mediated thresholds (i.e., nasal pungency, nasal localization, and eye irritation) lay about three orders of magnitude above odor thresholds, which ranged between 0.1 and 1.7 ppm. The results implied uniform chemesthetic sensitivity across tasks and sites of impact. In Experiment 2, normosmics and anosmics provided odor and nasal pungency thresholds, respectively, for three pairs of isomeric terpenes: alpha- and gamma-terpinene, alpha- and beta-pinene, and R(+)- and S(-)-limonene. Odor thresholds ranged between 1.4 and 19 ppm, that is, about an order of magnitude higher than those of the previous terpenes, with no substantial differences between odor thresholds of members of a pair. Regarding chemesthetic impact, only alpha-terpinene evoked nasal pungency. The overall outcome suggests comparable trigeminal chemosensitivity between nose and eyes and between normosmics and anosmics, as shown before for homologous n-alcohols. It also lends support to a previously derived solvation model of the chemesthetic potency of airborne substances, and indicates the likely importance of certain molecular-size restrictions for effective trigeminal impact.

Acyclic Monoterpenes↗

PubMed1998

Odor identification: perceptual and semantic dimensions.

Five studies explored identification of odors as an aspect of semantic memory. All dealt in one way or another with the accessibility of acquired olfactory information. The first study examined stability and showed that, consistent with personal reports, people can fail to identify an odor one day yet succeed another. Failure turned more commonly to success than vice versa, and once success occurred it tended to recur. Confidence ratings implied that subjects generally knew the quality of their answers. Even incorrect names, though, often carried considerable information which sometimes reflected a semantic and sometimes a perceptual source of errors. The second study showed that profiling odors via the American Society of Testing and Materials list of attributes, an exercise in depth of processing, effected no increment in the identifiability/accessibility beyond an unelaborated second attempt at retrieval. The third study showed that subjects had only a weak ability to predict the relative recognizability of odors they had failed to identify. Whereas the strength of the feeling that they would 'know' an answer if offered choices did not associate significantly with performance for odors, it did for trivia questions. The fourth study demonstrated an association between ability to discriminate among one set of odors and to identify another, but this emerged only after subjects had received feedback about identity, which essentially changed the task to one of recognition and effectively stabilized access. The fifth study illustrated that feedback improves performance dramatically only for odors involved with it, but that mere retrieval leads to some improvement. The studies suggest a research agenda that could include supplemental use of confidence judgments both retrospectively and prospectively in the same subjects to indicate the amount of accessible semantic information; use of second and third guesses to examine subjects' simultaneously held hypotheses about identity; use of category cuing or similar techniques to discover the minimum semantic information needed to precipitate identification; some use of subjects trained in quantitative descriptive analysis to explore whether such training enhances semantic memory; and judicious use of mixtures to explore perceptual versus semantic errors of identification.

Adult↗

PubMed1997

Topical corticosteroid treatment of anosmia associated with nasal and sinus disease.

OBJECTIVE: To establish the efficacy of topical corticosteroid nasal spray treatment of severe olfactory loss associated with severe nasal and sinus disease. DESIGN: Efficacy before and after open-label trial of topical corticosteroid nasal spray used exclusively in the head-down-forward position. SETTING: Taste and smell clinic of a university teaching hospital and research facility. PATIENTS: Taste and smell clinic patients with anosmia or severe hyposmia associated with paranasal sinus disease and nasal polyposis including 39 of 45 patients recruited from 1988 to 1994 who completed the topical corticosteroid treatment course and returned for subsequent testing. INTERVENTION: At least 8 weeks of treatment with flunisolide (Nasalide), 2 sprays in each nostril twice a day, with concurrent antibiotic treatment of any bacterial infection. MAIN OUTCOME MEASURES: Subjective olfactory symptoms, objective olfactory function tests, and otolaryngological evaluation (including endoscopic examination). RESULTS: Olfactory scores significantly improved following treatment (P < .001); signs of nasal and sinus disease significantly decreased (P < .001); and 26 (66%) of the patients reported a subjective improvement in their sense of smell. CONCLUSION: Topical corticosteroid nasal spray administered in a head-down-forward position is an effective treatment of severe olfactory loss associated with severe nasal and sinus disease.

Administration, Topical↗

PubMed1997

Perceptual and mental mixtures in odor and in taste: are there similarities and differences between experiments or between modalities? Reply to Schifferstein (1997)

D. Algom and W. S. Cain (1991b) found relative invariance in the pattern of judgments of perceptual and mental mixtures of banana and grass odors. Invariance held both for judgments of total intensity and for those of an individual constituent. For 2 tastes, H. N. J. Schifferstein (1997) found a pattern with both similarities to and differences from D. Algom and W. S. Cain's. A key difference lay in finding more symmetry of masking in mental mixtures than in perceptual mixtures. H. N. J. Schifferstein concluded from this alone that any similarity between the perceptual and mental arose from knowledge of "mixture suppression." The authors of this article do not refute the possibility; however, they reject the premise that a statistically reliable difference between the perceptual and the imaginal rules out imagery. The authors review relevant considerations and find no a priori reason to assume that what held for attributes in taste will hold for odors. An approach to resolve the issue is also suggested.

Attention↗

PubMed1997

Agonistic sensory effects of airborne chemicals in mixtures: odor, nasal pungency, and eye irritation.

Thresholds responses of odor, nasal pungency (irritation), and eye irritation were measured for single chemicals (1-propanol, 1-hexanol, ethyl acetate, heptyl acetate, 2-pentanone, 2-heptanone, toluene, ethyl benzene, and propyl benzene) and mixtures of them (two three-component mixtures, two six-component mixtures, and one nine-component mixture). Nasal pungency was measured in subjects lacking a functional sense of smell (i.e., anosmics) to avoid interference from olfaction. Various degrees of stimulus agonism (additive effects) were observed for each of the three sensory channels when testing mixtures. As the number of components and the lipophilicity of such components in the mixtures decreased, so did the degree of agonism. Synergistic stimulus agonism characterized the eye-irritation response for the most complex (the nine-component) and the most lipophilic (one of the six-component) mixtures. Physicochemical properties play a large role in the determination of sensitivity to airborne chemicals, particularly to their ability to evoke irritation. While this has revealed itself previously with respect to single chemicals, it seems to have relevance to mixtures as well.

Adult↗

PubMed1996

An analysis of nasal irritation thresholds using a new solvation equation.

In the present paper we have developed a quantitative structure-activity relationship (QSAR) equation for nasal pungency caused by nonreactive volatile organic compounds (VOCs). Our QSAR was developed upon previously published nasal pungency thresholds in anosmics, i.e., patients lacking a sense of smell and thus responding only to sensory irritation evoked by trigeminal nerve stimulation. The reported solvation equation, which fits the data with considerable precision, describes sensory potency in terms of interaction via electron pairs, dipolarity/polarizability, hydrogen bond acidity and basicity, and hydrophobicity. It correspondingly suggests relevant physicochemical properties of the biophase where the sensory response is brought about. The equation implies that in the range of molecular size where nonreactive VOCs can produce any pungency, transport from the air to the biophase strictly determines potency. In this respect, the potency of nasal pungency shares characteristics with the ability of VOCs to cause narcosis and anesthesia.

Adult↗

PubMed1996

Switch and bait: probing the discriminative basis of odor identification via recognition memory.

When people misidentify everyday odors, as they often do, their errors may conceivably lie in faulty perceptions or in faulty access to the names. Discussions of the matter usually focus on the latter, as if people had no problems with perceptual accuracy. (The problem of faulty access may get attention because its high subjective impact makes it particularly memorable, when it does occur.) However, studies have demonstrated breakdowns in ability to discriminate quality, from which it follows that people will misidentify items through perceptual confusions. Furthermore, misidentifications often contain considerable information about the identities of items, as if people simply did not perceive the items accurately, but perhaps fuzzily or with some perceptual bias. Recognition memory, with a 2-day interval between inspection and test, provided a vehicle to address two questions on this topic: (i) Would people notice that we had switched items and had presented for recognition items that matched their misidentifications rather than the original items inspected? (ii) Would people not only fall for the false bait, but actually identify the switched items correctly, and thereby imply that they were 'tuned' to perceive those odors? People commonly failed to notice the switches, i.e. took the bait and commonly identified the switched items with veridical names. Although subject to further study, the outcome suggests that when people give such names as garlic for vinegar, orange for lime, soy sauce for molasses and many others, the errors often lie largely at a perceptual stage of processing, i.e. at input rather than output.

Female↗

PubMed1995

Life-span development of odor identification, learning, and olfactory sensitivity.

In the first of three studies, children (aged 8 to 14 years) were found to perform worse than young and middle-aged adults in unprompted identification of doors, with average performance much like that of elderly adults. Comparisons on other tasks, specifically odor threshold, prompted odor identification, and object naming (Boston Naming Test), across the life span (five groups) revealed that children have the same excellent olfactory sensitivity as young adults and merely lack odor-specific knowledge that accumulates slowly through life. Such knowledge apparently accumulates so slowly that age-associated discriminative losses, measurable by early middle age, begin to wear away gains obtained through experience before odors can become overlearned. In the second study, a novel adaptive psychophysical method, the step procedure, confirmed the equivalent sensitivity of children and young adults. In the third study, a paired-associate task illustrated the sluggish course of odor learning. Young adults outperformed children, though the youngest group, first graders, made up ground relatively fast. For children and adults, common odors facilitated performance relative to novel odors. The outcome highlighted the relevance of semantic factors in odor learning irrespective of age.

Adolescent↗

PubMed1995

Relative sensitivity of the ocular trigeminal, nasal trigeminal and olfactory systems to airborne chemicals.

We measured thresholds for eye irritation and odor in homologous series of alcohols (ethanol, 1-butanol, 1-hexanol and 1-octanol), ketones (2-propanone, 2-pentanone, 2-heptanone and 2-nonanone), and alkylbenzenes (toluene, ethyl benzene and propyl benzene). Eye irritation thresholds were well above odor thresholds for all series. Both sensory thresholds declined with carbon chain length, a trend that has implicated lipophilicity in the potency of these and related stimuli. Eye irritation thresholds were remarkably close to nasal pungency thresholds obtained previously in persons lacking olfaction (i.e. anosmics). The agreement between the two thresholds implies that, despite differences in the mucus layer at the two sites and in the epithelial tissue itself, there is remarkable similarity at the site of stimulation. As a practical matter, the eyes could serve as the sites to assess potency for induction of nasal pungency, an assessment previously limited to testing anosmics. Presumably, for our brief stimulus presentations (1-3 s), the differences between ocular and nasal mucosae have little relevance to chemical sensitivity. Studies of the ability of homologous chemical series to evoke threshold eye irritation, nasal pungency and odor not only have practical value, but also can help to define the physicochemical properties of the receptor and perireceptor biophases.

Adult↗

PubMed1995

Comparison of models of odor interaction.

Subjects rated the overall perceived intensity of concentrations of the odorants cineole, geraniol, hexyl salicylate, and linalyl acetate smelled alone and in binary mixtures. The subjects also rated intensity of specified constituents (e.g. amount of cineole in cineole, and in mixtures of cineole and linalyl acetate). The intensity of the stronger component alone offered a close description of perceived intensity. In addition to the Stronger Component model, two other psychological models (Vector and U model) and two psychophysical models (UPL2 and Equiratio Mixture model) offered descriptions ranging from fair to very good. Psychological models gave better fits, but lack explanatory power. Some results indicated that weaker odors add more potently than stronger odors, an outcome incompatible with these models. The psychophysical models, based on the additivity of single components, generally overestimated perceived intensity. Judgments of individual qualities gave only slight encouragement to any expectation of differences in masking or maskability among odorants. The results highlight the need to test particular critical hypotheses regarding how people perceive mixtures.

Acyclic Monoterpenes↗

PubMed1994

Sensory reactions of nasal pungency and odor to volatile organic compounds: the alkylbenzenes.

Research assessed the independent contribution of the trigeminal and olfactory nerves to the detection of airborne chemicals by measuring nasal detection thresholds in subjects clinically diagnosed as lacking a functional sense of smell (anosmics) and in matched normal controls (normosmics). Anosmics can provide only odor-unbiased pungency thresholds. Normosmics provided odor thresholds. Stimuli included homologous alkylbenzenes (from toluene to octylbenzene), chlorobenzene, 1-octene, and 1-octyne. As seen before with homologous alcohols, acetates, and ketones, both types of threshold declined with increasing carbon chain length. Anosmics failed to detect alkylbenzenes above propylbenzene. The strong linear correlation between pungency thresholds and saturated vapor concentration for all tested compounds, as a whole, and the constancy of pungency thresholds expressed as percent of vapor saturation, suggests that nasal pungency from these substances relies heavily on a broadly tuned physicochemical interaction with a susceptible biophase within the cell membrane. Through such a nonspecific mechanism, low, subthreshold levels of a wide variety of volatile organic compounds of low reactivity-as found in many polluted indoor spaces-could add their sensory impact to precipitate noticeable sensory irritation.

Adult↗

PubMed1994

Olfactory-evoked potentials: assessment of young and elderly, and comparison to psychophysical threshold.

Olfactory-evoked potentials (OEPs) were recorded monopolarly at the Fz, Cz and Pz electrode sites in young adults and elderly subjects with an amyl acetate stimulus presented olfactometrically. Psychophysical odor thresholds for amyl acetate were determined using a two-alternative, forced-choice detection procedure. These demonstrated a decreased odor detection sensitivity in the elderly relative to tye young subjects. In accordance with the threshold findings, elderly subjects produced significantly smaller N1 and P2 amplitudes, and a trend towards longer latencies than younger subjects. Moreover, odor threshold was found to correlate with amplitude magnitude. The OEP findings, which are discussed in the context of previous OEP studies, offer promise as an objective, non-invasive measure of sensory function in both clinical and non-clinical settings.

Adult↗

PubMed1994

Odor identification by name and by edibility: life-span development and safety.

The study explored how subjects from childhood (8-14 years old) to elderly adulthood could identify the odors of 17 everyday products. Performance at naming followed an inverted U-shaped course over age, best in young adults and poorest in children and elderly. A discrimination task given to the adults revealed parallel age-related declines in ability to name and to discriminate odors. Correct identification by edibility exceeded that by name considerably. For dangerous household products, children achieved only 15% correct naming but 79% correct edibility/inedibility. Scenting of dangerous household products, however, may compromise the discriminability of these products from less harmful ones. "Fresh"-scented hypochlorite bleach yielded significantly more errors regarding its possible causticity than did unscented bleach. Such modifications of products would seem to necessitate other compensatory changes to enhance discriminability and thereby maintain safety.

Adolescent↗

PubMed1994

Odor quality: discrimination versus free and cued identification.

Eighty-two adults, ranging in age from young to elderly, performed odor-quality discrimination and both free and cued identification on six odorants presented at two intensity levels. The odorants simulated the real-world substances banana, licorice, cherry/almond, wintergreen, clove, and lemon. Performance on all three tasks declined with age, but improved with stimulus intensity. Performance at discrimination benefited from the mere availability of the six names during testing. Performance in cued identification far exceeded that in free identification and, for young and middle-aged adults, fell close to that for discrimination. For elderly adults, however, performance in cued identification fell substantially below that in discrimination. Although not entirely free of cognitive influences, discrimination seems to offer particularly clear resolution of alterations in olfactory functioning.

Adolescent↗

PubMed1993

Changes in taste and flavor in aging.

This study aims at understanding the role of mixtures (mutual quality suppression) in the evaluation of impact of the human aging process on the perception of taste. Heretofore, the effect of aging on taste has been directed at threshold and suprathreshold magnitudes of single chemicals (e.g., NaCl, sucrose, citric acid) in aqueous solution. Although absolute thresholds typically rise in advanced age (2 to 9 times, depending on the study), suprathreshold magnitude assessed by magnitude matching seems (except for bitter) to resist change in the way presbycusis spares suprathreshold loudness, fostering the impression that aging may handicap the aged little in the perception of food. Asked, however, to discriminate the presence-absence of the prescribed salt flavoring (nominally suprathreshold) in tomato soup, the young outperformed the middle-aged who, in turn, outperformed the elderly. Moreover, NaCl thresholds in the presence of tomato measured several times higher than in water, but the difference between the young and the elderly continued to hold. Elevation of threshold to much higher levels by mixture suppression leaves the young-elderly difference unchanged, implying that the elderly may fail to detect salt levels that really count in their diet. To examine the relation between age and taste mixtures, we measured detection thresholds: (1) for NaCl in citric acid, from zero to strong; (2) for sucrose in citric acid, from zero to strong; and (3) for citric acid in sucrose, from zero to strong. Whether in water alone or in a weak or strong suppressor, the elderly subjects' threshold was consistently 2 or 3 times higher than that of the young. Moreover, the way in which threshold for one quality rises with concentration of a suppressor is the same, except for constant upward displacement of the elderly peoples' threshold. In general, both young and elderly confuse salty and sour (show large suppression at all concentrations of the suppressor) much more than they confuse sweet and sour (seen mainly at high concentrations of the suppressor). Study of other mixtures is planned.

Adult↗

PubMed1992

Sensory irritation. Relation to indoor air pollution.

All mucosae of the body possess chemical sensitivity provided by the CCS. Airborne chemicals can stimulate the CCS through the ocular, nasal, and respiratory mucosae, evoking different pungent sensations, for example, stinging, irritation, burning, piquancy, prickling, freshness, and tingling. Pungent sensations elicited in the nose differ from odor sensations in various characteristics. They are achieved at considerably higher concentrations than those necessary to elicit odor, but they increase with the concentration of the stimulus in a steeper fashion than odor. Pungent sensations from mixtures of compounds show a higher degree of addition--relative to the pungency of the individual components--than that of odor sensations. Pungency is more resistant to adaptation than odor, and, unlike it, displays considerable temporal integration with continuous stimulation. Measurement of a reflex, transitory apnea produced upon inhalation of pungent chemicals holds promise as an objective indicator of the functional status of the CCS. Results from the measurement of this reflex have agreed quantitatively with sensory data in a number of studies, and have shown higher common chemical sensitivity in nonsmokers (compared to smokers), in females (compared to males), and in young adults (compared to the elderly). Research issues mentioned here include the following: 1. We can rarely validate the symptoms putatively caused by indoor air pollution objectively. Without such means, we will always have the potential problem of overreporting and embellishment. Although one person may seem more sensitive than another, the difference may lie in a greater proclivity to complain. 2. Studies of anosmic persons offer a simple means to understand the functional characteristics of the nasal CCS. Studies of chemical series in such subjects should eventually allow construction of quantitative structure-activity models for human pungency perception. The human data can be compared with relevant animal data when possible. 3. The rules of additivity of pungency in mixtures need explication. Regarding the possible role of VOCs in the creation of irritation, we need to ask whether subthreshold levels add up or even amplify each other to produce noticeable irritation. Do repetitive or continuous exposures to subthreshold concentrations increase sensitivity to those substances, so that they evoke pungency when they otherwise would not? Do the various mucose--ocular, nasal, throat--differ in their sensitivity? 4. Modulation of CCS sensitivity by long-term and short-term inhalation of various agents (for example, environmental tobacco smoke) would seem a suitable topic for further research.

Adult↗

PubMed1992

Transcatheter embolization of a high-flow congenital intrahepatic arterial-portal venous malformation in an infant.

An intrahepatic arterial-portal venous malformation (APVM) was diagnosed in a 4 1/2-month-old infant with portal hypertension. Visceral angiography showed a large saccular vascular space in the left hepatic lobe with a multiplicity of feeding arteries and drainage into the left portal vein. The lesion was successfully treated by transcatheter embolization following two unsuccessful surgical procedures. Two years later portal vein thrombosis with cavernous transformation was diagnosed, possibly a consequence of the high-flow arterial-portal shunt and its subsequent occlusion. Knowledge of the anatomic differences between this rare congenital APVM and the more commonly occurring arterial-portal fistula is crucial in planning effective transcatheter embolotherapy or surgery for these lesions.

Arteriovenous Fistula↗