Transforming growth factor-beta1 circulates in normal human plasma and is unchanged in advanced metastatic breast cancer.

A method has been developed to determine true plasma transforming growth factor beta (TGF-beta) levels by using the platelet alpha granule-specific marker, platelet factor 4, to correct for the TGF-beta contributed by platelets degranulated ex vivo. TGF-beta levels were measured on acid-ethanol extracts of human plasma using isoform-specific sandwich enzyme-linked immunosorbent assays. Normal human subjects had 4.1 +/- 2.0 ng/ml TGF-beta1 (range, 2.0-12.0; n = 42), <0.2 ng/ml TGF-beta2, and <0.1 ng/ml TGF-beta3 in their plasma. There were no significant changes with age or with hormonal status, but any given individual showed fluctuations of up to 3-fold in measured plasma TGF-beta levels due to unknown factors. Of 28 patients with advanced metastatic breast cancer, 2 had greatly elevated TGF-beta1 levels, while the rest were in the normal range. The presence of physiologically significant levels of TGF-beta1 in the plasmas of normal human subjects may indicate previously unsuspected endocrine roles for this peptide, while TGF-beta2 and TGF-beta3 appear to act only in a local autocrine/paracrine fashion.

The relative role of visual and non-visual cues in determining the perceived direction of "up": experiments in parabolic flight.

In order to measure the perceived direction of "up", subjects judged the three-dimensional shape of disks shaded to be compatible with illumination from particular directions. By finding which shaded disk appeared most convex, we were able to infer the perceived direction of illumination. This provides an indirect measure of the subject's perception of the direction of "up". The different cues contributing to this percept were separated by varying the orientation of the subject and the orientation of the visual background relative to gravity. We also measured the effect of decreasing or increasing gravity by making these shape judgements throughout all the phases of parabolic flight (0 g, 2 g and 1 g during level flight). The perceived up direction was modeled by a simple vector sum of "up" defined by vision, the body and gravity. In this model, the weighting of the visual cue became negligible under microgravity and hypergravity conditions.

Recharacterization of the start sites for the major human transforming growth factor-beta 1 mRNA.

The start sites for the major human TGF-beta 1 transcripts have been reexamined. A comparison of ribonuclease and S1 nuclease protection analyses on native TGF-beta 1 mRNA and in vitro transcribed human TGF-beta 1 transcripts of defined sizes places the most 5' start site for the native TGF-beta 1 message approx. 50 nucleotides upstream from the previously published start site at base +1. Furthermore, the same techniques indicate that the apparent downstream start site at base +271 is an artefact due to the presence of an A + T-rich island in the middle of an otherwise highly G + C-rich sequence. This is not apparent if S1 nuclease protection is used alone, which emphasizes the importance of using the two techniques in combination for this type of analysis. Thus the major 2.5 kb TGF-beta 1 band seen on Northern blots comprises only mRNA transcribed from the more upstream of the two previously characterized promoters. This has important implications both for the transcriptional and translational regulation of this growth factor.

Temporal dependencies in resolving monocular and binocular cue conflict in slant perception.

Observers viewed large dichoptic patterns undergoing smooth temporal modulations or step changes in simulated slant or inclination under various conditions of disparity-perspective cue conflict and concordance. After presentation of each test surface, subjects adjusted a comparison surface to match the perceived slant or inclination of the test surface. Addition of conflicting perspective to disparity affected slant and inclination perception more for brief than for long presentations. Perspective had more influence for smooth temporal changes than for step changes in slant or inclination and for surfaces presented in isolation rather than with a zero disparity frame. These results indicate that conflicting perspective information plays a dominant role in determining the temporal properties of perceived slant and inclination.

Stereopsis with persisting and dynamic textures.

We measured the percept of changing depth from changing disparity in stereograms composed of random-dot textures that were either persistent or dynamically changed on every frame (a dynamic random-dot stereogram). Disparity was changed between frames to depict a surface undergoing smooth temporal changes in simulated slant. Matched depth was greater with dynamic random-dot stereograms than with persistent random-dot stereograms. These results confirm and extend earlier observations at depth threshold. We posit an explanation based on cue conflict between stereopsis and monocular depth cues.

Depth selectivity of vertical fusional mechanisms.

We measured the ability to fuse dichoptic images of a horizontal line alone or in the presence of a textured background with different vertical disparity. Nonius-line measurements of vertical vergence were also obtained. Diplopia thresholds and vertical vergence gains were much higher in response to an isolated vertically disparate line than to one with a zero vertical-disparity background. The effect of the background was maximum when it was coplanar with the target and decreased with increasing relative horizontal disparity. We conclude that vertical disparities are integrated over a restricted range of horizontal disparities to drive vertical vergence.

Effects of horizontal and vertical additive disparity noise on stereoscopic corrugation detection.

Stereoscopic corrugation detection in the presence of horizontal- and vertical- additive disparity noise was examined using a signal detection paradigm. Random-dot stereograms either represented a 3-D square-wave surface with various amounts of Gaussian-distributed additive disparity noise or had the same disparity values randomly redistributed. Stereoscopic detection of 2 arcmin peak amplitude corrugations was found to tolerate significantly greater amplitudes of vertical-disparity noise than horizontal-disparity noise--irrespective of whether the corrugations were horizontally or vertically oriented. However, this directional difference in tolerance to disparity noise was found to reverse when the corrugation and noise amplitudes were increased (so as to produce equivalent signal-to-noise ratios). These results suggest that horizontal- and vertical-disparity noise pose different problems for dot-matching and post-matching surface reconstruction as corrugation and noise amplitudes increase.

Combined head and eye tracking system for dynamic testing of the vestibular system.

We present a combined head-eye tracking system suitable for use with free head movement during natural activities. This system provides an integrated head and eye position measurement while allowing for a large range of head movement (approx 1.8 m of head translation is tolerated). Six degrees of freedom of head motion and two degrees of freedom of eye motion are measured by the system. The system was designed to be useful for the evaluation of the vestibulo-ocular reflex (VOR). The VOR generates compensatory eye movements in order to stabilize gaze during linear or rotational motion of the head. Current clinical and basic research evaluation of the VOR has used a restricted range of head motion, mainly low-frequency, yaw rotation. An integrated eye-head tracking system such as the one presented here allows the VOR response to linear and angular head motion to be studied in a more physiologically relevant manner. Two examples of the utility of the integrated head and eye tracking system in evaluating the vestibular response to linear and angular motion are presented.

Post-rotatory nystagmus and turning sensations after active and passive turning.

We measured post-rotatory nystagmus and sensations of body rotation in standing subjects brought to rest in the dark after 3 minutes of each of the following conditions: 1) passive turning about the mid-body axis, involving only vestibular stimulation, 2) active turning about the mid-body axis, involving both vestibular stimulation and motor-proprioceptive activity in the legs, and 3) stepping round while remaining facing in the same direction on the center of a rotating platform with the head held in a stationary holder (apparent turning), involving only motor-proprioceptive activity. The same acceleration-velocity profile was used in all conditions. Post-rotatory nystagmus (slow phase) occurred in the same direction to passive body turning and was reduced in velocity after active body turning. After apparent turning, nystagmus was in the opposite direction as attempted body turning. Our theoretical analysis suggests that nystagmus after active turning should conform to the mean of the responses after passive and apparent turning rather than to their sum. The results conform more closely to the mean than to the sum, but with greater weight given to vestibular inputs than to motor-proprioceptive inputs. Post-rotatory sensations of self-rotation were in the expected opposite direction after passive turning and were lower in magnitude after active turning. After apparent turning, sensations of self-rotation were in the same direction as those after attempted turning--an effect known as the antisomatogyral illusion.

Vestibulo-ocular reflex deficits to rapid head turns following intratympanic gentamicin instillation.

The response of the vestibulo-ocular reflex following unilateral vestibular deafferentation by gentamicin ablation was studied using transient stimuli. The response to these rapid passive head turns showed a strong asymmetry with permanent, reduced gains toward the side of lesion. These gain reductions have large variation (gains of 0.26 to 0.83), which may result from preferential sparing of regularly firing afferent fibers following gentamicin ablation. Based on the size and nature of the nonlinearity, an explanation based on Ewald's second law was discounted.

Alternating cisplatinum and VAC ineffective in end stage squamous cell carcinoma of the head and neck.

Sixteen patients with end stage squamous cell carcinoma of the head and neck were admitted to a phase II study of alternating courses of cisplatinum (100 mg/m2) and VAC (vincristine 1.4 mg/m2, adriamycin 50 mg/m2, cyclophosphamide 750 mg/m2) given at three weekly intervals. Only two patients achieved a response (12 per cent). The median survival time was 62 days which is much the same as that of a similar group of patients who received no chemotherapy in a previous trial (70 days).

Lateral cervical cysts: a review of 42 cases.

A review of forty-two patients presenting over a ten year period with a histological diagnosis of lateral cervical (branchial) cyst was undertaken. Most occurred in the second and third decades (29/42), there was a slight female predominance (29/42). Thirty-five lesions presented at the classic site, 7 presented elsewhere in the neck. Ten lesions were painful on presentation, none of these were associated with systemic signs of infection. Preoperative diagnosis was correct in only 22 cases and was more likely to be incorrect when on presentation the lesion was painful, located away from the classic site or was solid to palpation. Incision of painful cysts led to increased patient morbidity. It is suggested that greater awareness of less usual presentations of lateral cervical cysts and use of fine-needle aspiration biopsy would improve diagnostic accuracy and reduce morbidity.

Pulmonary sequestration: a review of 12 cases.

A review of patients over a twenty-three year period with a diagnosis of pulmonary sequestration was undertaken. Of the twelve patients with this diagnosis, ten had intralobar sequestrations, and two had the extralobar variety. The most common presenting complaint, in six of the patients, was an unresolving localised chest infection. All had abnormal plain chest radiographs. There was a high incidence of an anomalous vascular supply, and aortography was useful in investigation. Operative management consisted of segmentectomy or lobectomy for the intralobar form and simple excision for the extralobar form with good results.

Peritonsillar infection in Christchurch 1990-2: microbiology and management.

AIM: To review the management and microbiology of peritonsillar infection in Christchurch. METHOD: The hospital records of patients admitted acutely to Christchurch Hospital with peritonsillar infection between January 1990 and December 1992, were reviewed. RESULTS: 109 patients were admitted with peritonsillar infection, of which 74 (68%) were found to have a peritonsillar abscess. Of these 74, needle aspiration was performed in 22, incision and drainage in 15, both aspiration and drainage in 31, and acute tonsillectomy in 6. Interval tonsillectomy was performed in 35 patients. Sixteen pathogenic bacterial groups or species were cultured from 39 aspirates. Of the total number of bacteria isolates, obligate anaerobes were cultured in 48%, and group A beta-haemolytic streptococci in 29%, while aerobic beta-lactamase producing bacteria were cultured in only 6%. CONCLUSION: Central to the management of peritonsillar abscess is drainage. This was commonly achieved by needle aspiration and/or incision. As beta-lactamase producing organisms are infrequent, penicillin remains the antibiotic of choice. Metronidazole may be required in a non responding patient, particularly if resistant anaerobes are cultured.

Patient evaluation of otolaryngology department service at Christchurch Hospital.

One hundred and four consecutive patients seen in the ENT department for consultation and inpatient treatment completed a structured questionnaire at their first postoperative (or posttreatment) outpatient clinic appointment. The aims of the survey were to ascertain the patients opinions and perceptions regarding the ENT department service in a variety of areas. Satisfaction was high in areas of medical and nursing care and with the information given regarding treatment. The major area of dissatisfaction was with waiting times, particularly waiting times at appointments during ENT outpatient clinics.

Carcinoma of the glottic larynx: the Christchurch experience.

AIMS: to establish the local control and survival rates for glottic laryngeal cancer, and to determine the incidence of second primary cancers after treatment of the original tumour. METHODS: a retrospective review of all patients with glottic cancers treated in Christchurch over a five year period, with a minimum follow up of five years. RESULTS: between 1979 and 1984, 83 patients with laryngeal cancer were treated in Christchurch Hospital. Forty-seven of these patients had cancers of the glottic larynx. Overall, 39 of 45 patients were free of their laryngeal cancer at five years (two were lost to follow up). Eight of 45 developed a second primary cancer, usually lung or oesophagus, and this was invariably fatal. CONCLUSION: with multidisciplinary management of head and neck cancers satisfactory control rates can be achieved, but since these patients are usually heavy smokers and drinkers, they are at high risk of developing a second primary cancer. The use of chemopreventative agents is mentioned.

Microtympanometry, microscopy and tympanometry in evaluating middle ear effusion prior to myringotomy.

OBJECTIVE: To determine the accuracy of a hand-held microtympanometer (Microtymp, Welch Allyn) used by a general practitioner when compared with findings at myringotomy. METHOD: Independent preoperative assessment of children's ears using microtympanometry by a general practitioner, microscopy and pneumatic otoscopy by a specialist otologist and impedance bridge tympanometry by a specialist audiologist were performed and compared with findings at myringotomy. SUBJECTS: Fifty children (100 ears) on the waiting list for bilateral myringotomies and ventilation tube insertion for recurrent acute otitis media or otitis media with effusion. RESULTS: Microscopy with pneumatic otoscopy had a 90.9% sensitivity and a 92.9% specificity in detecting middle ear effusions. Impedance bridge tympanometry had a 94.4% sensitivity and a 71.8% specificity if type B and C2 were combined to predict middle ear effusion. Microtympanometry had 100% sensitivity and 75% specificity if type B and C tympanograms were combined; if type B tympanograms alone were used, a sensitivity of 83.4% and specificity of 75% in predicting middle ear effusions was obtained. CONCLUSION: The Microtypm is a useful instrument in general practice for assessment of middle ear effusions as no ears with fluid were missed in this study if type B and C tympanograms were considered abnormal. The Microtymp would also be useful as a screening instrument by suitably trained personnel.

Aspiration cytology in the diagnosis of head and neck masses: the early Christchurch experience.

Fine needle aspiration cytology has been performed on patients presenting with head and neck masses in Christchurch since mid-1985. The results of an initial 120 aspirations were reviewed. Histology was available to compare with the cytology result in 58% of cases. Clinical review was used to assess the accuracy of the cytology result in the remaining cases. The majority of the masses aspirated were of benign origin (72%). The cytological diagnosis was accurate in 79% of cases. Of the remaining aspirates, 13% were inaccurate and 8% nondiagnostic. The sensitivity for malignant lesions was 100%, with 86% specificity (for benign lesions). Particular diagnostic difficulty was found in the differentiation between some salivary gland tumours, and the assessment of aspirates from neck masses after combined therapy (radiotherapy and surgery). Fine needle aspiration cytology is of considerable value in the management of head and neck masses.