Reliability of a common solution-based taste perception test: implications for validity and a briefer test.

The aim of this study was to assess test-retest reliability of a common method for quantifying taste perception and its association with gustatory responses and individual risk for obesity and related health conditions. Forty-six healthy adults rated 20 mixtures comprised of 5 dairy beverages varied in fat content and mixed with sugar concentrations of 0%, 5%, 10%, and 20%, following existing procedures. Individuals rated the sweetness, creaminess, and pleasantness of each mixture during two taste testing sessions occurring 7±2 days apart. Test-retest correlations were of the expected magnitudes (r≥.50) only for the pleasantness ratings of mixtures with higher sugar concentrations. Correlations for sweetness and creaminess taste perception ratings were low, indicating that such ratings may not be reliable over approximately one week, and challenging the validity of such ratings for measuring trait taste perception. A shortened version of the test may be warranted.

Surfactant protein D in Pseudomonas aeruginosa keratitis.

PURPOSE: To determine the importance of surfactant protein D in Pseudomonas keratitis. METHODS: The surfactant D status of wild-type and surfactant D-deficient Black Swiss mice was confirmed by PCR reactions and immunoblot assay. Mouse corneas were infected with one of three strains of P. aeruginosa. At 1, 2, 3, and 6 days postinfection, eyes were scored by slit-lamp examination and bacteria per cornea quantified. RESULTS: Infected wild-type mice had slit-lamp scores on 3 and 6 days postinfection that were significantly lower than those of surfactant D-deficient mice (p

Adaptive seasonal trend in brood sex ratio: test in two sister species with contrasting breeding systems.

Evolutionary theory predicts adaptive adjustment in offspring sex ratio by females. Seasonal change in sex ratio is one possibility, tested here in two sister species, the Common sandpiper and the Spotted sandpiper Actitis hypoleucos and A. macularia. In the monogamous Common sandpiper, males are the most competitive sex. In each of 3 years, there was a change from mainly sons in early clutches to mainly daughters in late clutches. This seasonal adjustment of clutch sex ratio took place within the female before the eggs were laid, not by differential egg or chick survival. The sex of all eggs laid in the clutches used here was determined molecularly from chick blood taken at the time of hatching. The Spotted sandpiper in contrast is polyandrous, with partly reversed sex roles. There was no seasonal trend from sons to daughters in this species. When tested together, the two species differed significantly as predicted by the hypothesis of adaptive sex ratio adjustment by females.

Effects of weather on corticosterone responses in wild free-living passerine birds.

Harsh weather can have devastating effects on both the survival and the breeding success of wild animals. Corticosterone, released in response to the stress caused by harsh conditions, may trigger physiological and behavioral changes that help ameliorate these effects. We examined three species of Arctic-breeding passerine birds for correlations between circulating plasma corticosterone levels and weather conditions at the time of capture. Furthermore, because persistently poor weather conditions may be required to initiate a stress response, we also looked for a relationship between corticosterone levels and weather conditions over the 24 and 72 h preceding capture. None of the three species showed substantial effects of weather on unstressed corticosterone levels during the breeding season, although one species showed a significant relationship with stress-induced corticosterone levels. In two species, however, variations in weather during molt (an energetically costly period when birds replace their feathers) explained from 35 to 88% of the individual variation in corticosterone levels. In a third molting species, weather conditions in the preceding 24 and 72 h explained between 20 and 30% of the individual variation in corticosterone levels. It thus appears that adverse weather may be a potent stimulator of corticosterone release during molt, but not during the breeding season. Although extreme weather conditions (those experienced once every few years) can disrupt breeding, since none of the birds abandoned breeding we might conclude that the storms in this study were well within the ability of the birds to cope physiologically.

Learning about categories that are defined by object-like stimuli despite impaired declarative memory.

Exposure to members of a category facilitates later categorization of similar but novel instances of the category. Past studies have suggested that category knowledge can be acquired implicitly and independently of declarative memory. However, these studies have relied on dot pattern stimuli that, unlike most real-world objects, are difficult to verbalize and cannot be broken into component features. It is therefore unclear how relevant such studies are to an understanding of everyday categorization. In the present studies, category learning in amnesic patients was tested with stimuli that both exhibit discrete features and are easy to describe (namely, cartoon animals). Amnesic patients were as competent as healthy volunteers in learning to categorize these animals, despite their impairment in recalling the animals' features. The results suggest that the implicit acquisition of category knowledge is a common process in everyday experience, and that it can occur whenever individuals encounter a large group of related items.

Impaired transverse patterning in human amnesia is a special case of impaired memory for two-choice discrimination tasks.

Three amnesic patients with damage limited to the hippocampal formation, a severely amnesic patient with extensive medial temporal lobe damage, and 9 controls were tested on the transverse patterning problem (A + B-, B + C-, and C + A-) and also on 2 control problems. One of the control problems was matched to the transverse patterning problem with respect to the number of pairwise decisions that were required. The 2nd control problem was matched to the transverse patterning problem with respect to the number of trials needed by controls to learn the task. The amnesic patients were impaired at solving both the transverse patterning problem and the control problems. The findings suggest that impaired learning of the transverse patterning problem by amnesic patients derives from their general impairment in declarative memory, which affects performance on most 2-choice discrimination tasks.

Retrograde amnesia for facts and events: findings from four new cases.

Two patients with presumed hippocampal formation lesions and two patients with more extensive temporal lobe damage, all of whom became amnesic in a known year, were given tests of anterograde and retrograde memory function. The two patients with hippocampal formation lesions had moderately severe anterograde amnesia and limited retrograde amnesia for facts and events that affected, at most, the decade preceding the onset of amnesia. Content analysis could not distinguish the autobiographical recollections of the patients from the recollections of control subjects. The two patients with more extensive temporal lobe damage had severe anterograde amnesia and extensive retrograde memory loss for both facts and events. The results suggest that whether retrograde amnesia is temporally limited or very extensive depends on whether the damage is restricted to the hippocampal formation or also involves additional temporal cortex.

Airway management in Pierre Robin sequence.

There is a great deal of controversy regarding the long-term management of airway obstruction in children with Pierre Robin sequence. All 23 pediatric otolaryngology fellowship programs were surveyed to determine their current practice patterns. Issues that were addressed included methods of evaluation of airway obstruction, including polysomnography, choices for home care in children in whom observation and positioning treatment failed, and complications of the various treatment modalities. The lack of unanimity among the respondents mirrors the controversy found in the literature. Though tracheotomy appears to be favored as the method of long-term management, responses from those surveyed often were based on emotions as much as on scientific data. This report details those findings and offers suggestions to clinicians involved with the management of patients with Pierre Robin sequence with airway compromise.

Impaired recognition memory in patients with lesions limited to the hippocampal formation.

A recent literature survey of results from a widely used recognition memory test raised questions about the extent to which recognition memory impairment ordinarily occurs in human amnesia and, in particular, whether recognition memory is impaired at all after damage limited to the hippocampal region (J. P. Aggleton & C. Shaw, 1996). Experiment 1 examined the performance of 6 amnesic patients on 11 to 25 different recognition memory tests. Three patients had bilateral lesions limited primarily to the hippocampus (G.D.) or the hippocampal formation (W.H. and L.M.), as determined by postmortem, neurohistological analysis (N. Rempel-Clower, S. M. Zola, L. R. Squire, & D. G. Amaral, 1996). All 6 patients exhibited unequivocally impaired recognition memory. In Experiment 2, the 3 patients still available for study were each markedly impaired on a test of object recognition similar to the kind used to test recognition memory in nonhuman primates. Recognition memory impairment is a robust feature of human amnesia, even when damage is limited primarily to the hippocampus.

Travellers' diarrhoea and the effect of pre-travel health advice in general practice.

BACKGROUND: Rates of travel-related diarrhoea vary from 8% to 50% depending on the country visited. Travellers' diarrhoea has social, health and economic costs. The impact of these may be reduced by relevant pre-travel advice. Little is known of the effect of pre-travel advice on the incidence of diarrhoea among travellers abroad. AIM: To determine the 'true' attack rate of travellers' diarrhoea and to assess the effectiveness of pre-travel health advice in reducing the incidence of diarrhoea and the need for subsequent GP consultation. METHOD: A retrospective study was carried out in a general practice in Stirling, Scotland, using a standardized, structured questionnaire to obtain demographic details and patients' home and foreign health experience in the previous 12 months. The questionnaire was administered to a 20% sample (n = 1771) of practice patients aged 16 years or over, stratified by age and sex. Main outcome measures were reported diarrhoeal illness while abroad, its management and outcome, and a record of diarrhoea in the two weeks prior to responding to the questionnaire. RESULTS: The response rate was 97% (n = 1649). Of those responding, 44% had travelled abroad in the past 12 months; 39% of travellers reported having diarrhoea while abroad, while 6% of the same group reported diarrhoea in the two weeks prior to being questioned; 9.7% of non-travellers reported diarrhoea in the two weeks prior to being questioned. Travellers were 6.5 times more likely to experience diarrhoea while abroad than when spending a comparable 2-week period at home. Travellers who had sought pre-travel advice were more likely to be travelling to a high-risk destination (P < 0.0001) and were more likely to suffer diarrhoea while abroad (P < 0.05); however, they were less likely to need medical help while abroad or on their return (P < 0.0001). The results indicate a markedly higher attack rate of diarrhoea in patients travelling abroad than would be expected if they stayed at home. CONCLUSION: Pre-travel advice does reduce the need for medical assistance while abroad; it also reduces GP work-load in terms of post-travel health consultations with returning travellers.

When amnesic patients perform well on recognition memory tests.

Extended exposure to study material can markedly improve subsequent recognition memory performance in amnesic patients, even the densely amnesic patient H.M. To understand this phenomenon, the severely amnesic patient E.P., 3 other amnesic patients, and controls studied pictorial material and then were given either a yes-no (Experiment 1) or a 2-alternative, forced-choice (Experiment 2) recognition test. The amnesic patients and controls benefited substantially from extended exposure, but patient E.P. consistently performed at chance. Furthermore, confidence ratings corresponded to recognition accuracy. The results do not support the idea that the benefit of extended study time is due to some kind of familiarity process made available through nondeclarative memory. It is likely that amnesic patients benefit from extended study time to the extent that they have residual capacity for declarative memory.

Magnetic resonance imaging determination of tracheal orientation in normal children. Practical implications.

OBJECTIVE: To determine normative anatomical data on the pediatric upper airway. DESIGN: Anatomical study of the trachea and surrounding structures in vivo using magnetic resonance imaging. Three-dimensional positions of the hyoid bone, sternum, skin, and trachea were determined. Tracheal angulation was measured from the vertical plane. SUBJECTS: One hundred children (53 males and 47 females) undergoing magnetic resonance imaging of the brain or chest. INTERVENTION: None. RESULTS: Ages ranged from 2 days to 20.4 years, with a median of 6.05 years. Gender differences were not significant. The mean distance from the hyoid bone to the sternal notch was 63.0 mm (SD, 22.04 mm). The skin to anterior tracheal wall distance averaged 9.34 mm (SD, 3.29 mm), and tracheal diameter averaged 8.48 mm (SD, 2.88 mm). The trachea was not found to be a linear structure. An anterior angulation change of 9.9 degrees (SD, 7.89 degrees) was detected. The point of inflection was found to lie below the sternal notch in children younger than 2 years and above the notch in older children. CONCLUSIONS: Normal anatomical data of the pediatric airway have been acquired using magnetic resonance imaging. Because the trachea exhibits a previously unknown anterior angulation, current design of tracheotomy tubes may not be ideal. Rigid tracheotomy tubes that do not conform to the anatomical structure of the trachea may be responsible for suprastomal collapse or innominate artery erosion.

Results of intraoral cortical bone screw fixation technique for mandibular fractures.

The intraoral cortical bone screw fixation technique carries many advantages over traditional methods of intermaxillary fixation. Simplicity of the technique, reduction of operative time, and reduction of risk of transmission of human immunodeficiency virus and hepatitis make this an important technique in the armamentarium of busy facial trauma surgeons. Since 1992, 45 mandibular fractures in 29 patients treated with the intraoral cortical bone screw technique for intermaxillary fixation were retrospectively analyzed. At our institution, this technique has become the workhorse method of repairing most mandibular fractures and is associated with minimal complications.

The impact of travel acquired illness on the world traveller and family doctor and the need for pre-travel health education.

This retrospective study involved a 20% quota, age and sex stratified sample of people over 16 years of age, presenting to a group medical practice over a period of one year (N = 1568). A standardised, computer-scored, self-report questionnaire was administered. The response rate was 98.3%. 42% of respondents had travelled outwith the UK in the previous year. Of those, 42% had become ill whilst abroad. In 20.5% of cases the illness settled without treatment. However, 26% of the patients required consultation with a doctor whilst abroad and 48.4% of those becoming ill required further attention from the family doctor on return home. 5% of ill travellers were admitted to hospital abroad. 8% of all travellers did not have medical insurance cover. A large and significant population of travellers become ill whilst abroad, and travel-acquired illness has a large impact on general practice, with 1 in 5 travellers seeking GP consultation on return home. Improved practice-generated pre-travel health advice might decrease this burden on primary care.