Effects of ingesting large prey on the kinematics of rectilinear locomotion in Boa constrictor

Large and stout snakes commonly consume large prey and use rectilinear crawling; yet, whether body wall distention after feeding impairs rectilinear locomotion is poorly understood. After eating large prey (30-37% body mass), all Boa constrictor tested could perform rectilinear locomotion in the region with the food bolus despite a greatly increased distance between the ribs and the ventral skin that likely lengthens muscles relevant to propulsion. Unexpectedly, out of 11 kinematic variables, only two changed significantly (P<0.05) after feeding: cyclic changes in snake height increased by more than 1.5 times and the longitudinal movements of the ventral skin relative to the skeleton decreased by more than 25%. Additionally, cyclic changes in snake width suggest that the ribs are active and mobile during rectilinear locomotion, particularly in fed snakes, but also in unfed snakes. These kinematic changes suggest that rectilinear actuators reorient more vertically and undergo smaller longitudinal excursions following large prey ingestion, both of which likely act to reduce elongation of these muscles that may otherwise experience substantial strain.

Accuracy of patient self-medication with topical eardrops

Topical eardrops are commonly prescribed by otolaryngologists and general practitioners and many believe that patient compliance is poor, although this has not been studied in a properly controlled manner. Thirty-nine patients with otitis externa were reviewed four times during a two-week course of topical eardrops and their treatment compliance studied. The patients tended to undermedicate themselves, and this tendency increased over the two-week period. Patients were administering significantly fewer drops by the end of day 11 than by the end of day 3 (p = 0.2). Compliance patterns were extremely poor, in that only 40 per cent of patients were managing to self-medicate within a 25 per cent error margin by the end of day 3. These findings may have future implications in the ongoing debate on eardrop use.

The effect on nasal resistance of an external nasal splint during isometric and isotonic exercise

The now commonplace wearing of external nasal splints by sportsmen and athletes has never been scientifically evaluated. The present study looks into the effect of both isometric and isotonic exercise on nasal resistance and examines if this is altered by the wearing of an external nasal splint. Twenty subjects who did not suffer from rhinitis were tested. Nasal resistance measurements were recorded using an anterior rhinomanometer before and after exercise, with and without an external nasal splint. Pulse and blood pressure were measured using a Criticare Inc. model 508 physiological monitor before and after exercise. Significant changes were observed in pulse (P < 0.001) and both systolic (P < 0.002) and diastolic (P < 0.001) blood pressure in response to isotonic exercise and pulse (P < 0.0001) and diastolic blood pressure (P < 0.0006) in isometric exercise. Significant differences were seen in nasal resistance when the splint was applied before (P < 0.001) and after exercise in both groups (P < 0.003). No significant difference was observed between the post-isotonic exercise groups with and without the splint (P = 0.167) but significant differences were seen in the isometric group (P < 0.0001). External nasal splints decrease nasal resistance at rest but are of little proven value when performing isotonic exercise however significantly reduce nasal resistance during isometric exercise.

The effect of cold water immersion on the nasal mucosa

The response of the nasal mucosa to cold water immersion is not well known. We have attempted to document this response in normal individuals. Seventeen individuals with no history of nasal disease or allergy were studied. All subjects were asked to perform sustained cold water (15 degrees C) immersion of their hand and forearm on the side of the obstructed nostril for a period of 5 min. The nasal cross-sectional area was measured on both sides of the nose using an acoustic rhinometer. The individuals were then rested for at least 30 min and the test repeated with immersion of the opposite hand. There was a significant fall in nasal cross-sectional area on the side of immersion (median change = 0.32 cm2, P = 0.0003) with a significant rise in nasal cross-sectional area on the none test side (median change = 0.35 cm2, P = 0.0003). There were no significant differences between these results and those obtained by immersion on the opposite side. The results indicate that cold water immersion produces nasal obstruction and that both afferent and efferent arms of this reflex are side-specific.

The effect of pH of douching solutions on mucociliary clearance

The effect of the pH of hypertonic saline nasal douching solutions on mucociliary clearance was studied in order to investigate the common notion that such solutions should be buffered alkaline. Thirty normal subjects were included in a randomised controlled crossover trial. Mucociliary clearance was measured by the saccharin clearance time. There was no difference in mucociliary clearance after douching with a non-buffered solution and a solution buffered to pH 8. However both solutions significantly improved mucociliary clearance compared to the baseline (P < 0.001) probably on account of their hypertonicity.

Effect on nasal resistance of an external nasal splint and isotonic exercise

OBJECTIVES

The now commonplace wearing of external nasal splints by sportsmen and athletes has never been scientifically evaluated. The present study looks into the effect of isotonic exercise on nasal resistance, and examines whether this effect is altered by the wearing of an external nasal splint.

METHODS

Twenty subjects not suffering from rhinitis were tested. Nasal resistance measurements were recorded using an anterior rhinomanometer before and after isotonic exercise with and without an external nasal splint. Pulse and blood pressure were measured before and after exercise.

RESULTS

Significant changes were observed in pulse (p < 0.001) and both systolic (p < 0.002) and diastolic (p < 0.001) blood pressure in response to exercise. Significant differences were seen in nasal resistance when the splint was applied (p < 0.001) and after exercise (p < 0.003). No significant difference was observed after exercise when the splint was worn (p = 0.167).

CONCLUSIONS

External nasal splints decrease nasal resistance at rest but are of little value during isotonic exercise.

The nasal response to axillary pressure

The changes in ipsilateral sympathetic tone in response to axillary pressure are well known. However, the response of the nasal mucosa is less well documented. We have attempted to demonstrate this response in normal individuals. Ten individuals with no history of nasal disease or allergy were studied. All subjects were exposed to sustained pressure, using a crutch, for a period of 5 min. Nasal cross-sectional area was measured on both sides of the nose using an acoustic rhinometer along with pulse and blood pressure. The individuals were then rested for at least 30 min and the test repeated with pressure applied to the opposite side. Statistical analysis was performed by non-parametric methods. There was a significant fall in nasal cross-sectional area on the side of pressure (median change = 0.09 cm2, P < 0.01) while cross-sectional area in the contralateral nasal passage increased (median change = 0.35 cm2, P = 0.01). There were no significant differences between these results and those obtained by axillary pressure on the opposite side. Pulse and diastolic blood pressure rose with axillary pressure while systolic blood pressure remained unaltered. There was no difference in the laterality in the blood pressure response. The results indicate that axillary pressure produces nasal congestion and both afferent and efferent arms of this reflex are side-specific.

The posterior cricoarytenoid ligaments and their relationship to the cadaveric position of the vocal cords

Much debate has occurred over the last century regarding the reason for the cadaveric position of the membranous vocal cord. This study attempts to identify the determining factors of the position of the vocal cord. Serial dissection of 36 cadaveric larynges was carried out and laryngeal measurements taken. The cadaveric position of the vocal cords was correlated to that of the posterior cricoarytenoid ligaments and it was found that the two were directly related. The study shows that the major determinant of the position of the denervated vocal cord is the position of the posterior cricoarytenoid ligament.

The nasal response to isometric exercise in non-eosinophilic intrinsic rhinitis

The exact pathophysiology of intrinsic rhinitis is not fully understood. The generally held belief is that it is due to an imbalance between the outflow of the nasal sympathetic and parasympathetic nervous systems, perhaps due to excessive parasympathetic or reduced sympathetic activity. In this study the nasal airway response to a predominantly sympathetic stimulus, isometric exercise, was studied in 19 patients with intrinsic rhinitis and compared with 16 normal patients. Isometric exercise took the form of a handgrip stimulus using a hand dynomometer. Following sustained handgrip, a small fall of nasal resistance in the normal group (0.058 kPas/1) and a moderate rise in nasal resistance in the rhinitis group (0.242 kPas/1) was found. Pulse and blood pressure changes were the same in both groups with a significant rise in pulse rate and diastolic blood pressure. The study shows that there is an abnormal response to isometric exercise in intrinsic rhinitis, perhaps due to relative nasal sympathetic hyposensitivity.

The nasal response to isometric exercise

The cardiovascular response to isometric exercise is well understood. However, the response of the nasal mucosa is less well known. We have attempted to document this response in normal individuals. Ten individuals with no history of nasal disease or allergy were studied. All subjects were asked to perform sustained handgrip on the side of the obstructed nostril for a period of 5 min at 30% of maximum voluntary effort. Nasal cross-sectional area was measured on both sides of the nose using an acoustic rhinometer. The individuals were then rested for at least 30 min and the test repeated with pressure applied by the opposite hand. Statistical analysis was performed by non-parametric methods. There was a significant fall in nasal cross-sectional area on the side of exercise median change = 0.09 cm2, P < 0.01) while cross-sectional area in the contralateral nasal passage increased (median change = 0.35 cm2, P = 0.01). There was no significant differences between these results and those obtained by handgrip on the opposite side. The results indicate that isometric exercise produces nasal obstruction (isotonic exercise) and both afferent and efferent arms of this reflex are side-specific.

An alternative to regular dressings for otitis externa and chronic supperative otitis media?

Otitis externa and chronic otitis media often present to the otolaryngologist with a discharging ear. The conventional method of treatment is to perform regular aural toilet and insert medicated dressings into the external auditory canal. This treatment is either performed by trained nurses or medical staff, but in either case is time consuming. This study compares the efficacy of the above standard regimen with a novel treatment where a single aural toilet is carried out and medicated ointment instilled into the ear. Both regimens were evaluated at three weeks. Our results shows that there was no significant difference between the two treatment regimens with regard to the resolution of either of the conditions studied or the improvement in the symptom status of the patients. On the basis of this it would seem that a single aural toilet and instillation of medicated ointment is a valid treatment option, cuts down hospital attendance and could be performed in the community by general medical practitioners or trained practice nurses.