Simplified measurement of auditory filter shapes using the notched-noise method.

The shape of the auditory filter at a given centre frequency can be estimated by measuring the threshold for detecting a sinusoid presented in a spectral notch in a noise masker, as a function of notch width. Laboratory studies using this method have typically been based on threshold measurements for between 13 and 19 notch widths. In this note, we describe how both the overall sharpness and asymmetry of the auditory filter in hearing-impaired subjects can be estimated with reasonable accuracy using only five notch widths. This considerably reduces the testing time needed, making it possible to apply the method in clinical testing.     

Alexithymia in Holocaust Survivors with and Without PTSD

Alexithymia was measured in non-treatment seeking, community-dwelling Holocaust survivors using the Toronto Alexithymia Scale—Twenty Item Version (TAS-20). Scores of survivors with (n = 30) and without (n = 26) posttraumatic stress disorder (PTSD) were compared, and associations among alexithymia, severity of trauma, and severity of PTSD symptoms were determined. Survivors with PTSD had significantly higher scores on the TAS-20 compared to survivors without PTSD. TAS-20 scores were significantly associated with severity of PTSD symptoms, but not with severity of trauma. This study adds to our knowledge of the relationship between alexithymia and trauma by demonstrating that this characteristic is related to the presence of posttraumatic symptoms and not simply exposure to trauma.     

Binge drinking: prevalence, patterns and policy

This paper presents analyses of the pattern of ‘bingedrinking’ in Wales, based on data drawn from a 1993 surveyof 12 167 (67%) 18–64 year olds resident in 15 212 householdsin Wales. Binge drinking, defined as drinking half the weeklyrecommended units of alcohol in a single drinking session, wasfound to be most prevalent among young adults, males, the manualsocial group, those who did not undertake any further educationafter secondary school, those who are single, divorced or separated,beer drinkers and those who concentrate most of their drinkingat weekends. 28.2% of men and 8.2% of women reported binge drinkingat least once a week, of whom about 42% felt that their levelof drinking was harmful to their health. About a quarter statedthat they would like to reduce their alcohol consumption butonly a small number had been advised to do so by their GeneralPractitioner. The public health impact of binge drinking isdiscussed. It is recommended that sensible drinking messagesshould emphasize the need to reduce binge drinking as well asto moderate overall weekly consumption and should be supportedby policies to create environments that support sensible alcoholuse.     

Acute Sinusitis in the Rabbit: A New Rhinogenic Model

The objective of this study was to create a rhinogenic model of sinusitis using an implanted foreign body in the nasal cavity of the rabbit. The study design was a prospective controlled trial of the experimental design. In this model an obstructing foreign body was placed into the nasal cavity and then impregnated with pathogenic bacteria. This model was studied histologically using wholemount techniques. Quantitative assessment of the degree of inflammation was made for the maxillary and ethmoid sinus and for overall effect for each animal. Bacteriologic study was performed in a limited number of animals. The results indicated that a significant infection develops in about half of animals. This peaks in intensity between 1 and 2 weeks after implantation and subsequently subsides with some evidence of long-term changes present after 4 weeks. It is concluded that this is a viable and perhaps preferable animal model to study sinusitis. Further investigation is necessary to completely characterize this model.     

Reevaluating the carcinogenicity of ortho-toluidine: A new conclusion and its implications

The aromatic amine ortho-toluidine has been recognized by IARC as an animal carcinogen for the past decade. Three recent epidemiological studies of worker populations have now implicated this chemical as a human bladder carcinogen. In a study by E. Ward, A. Carpenter, S. Markowitz, D. Roberts, and W. Halperin ((1991), J. Natl. Cancer Inst. 83, 501–506), workers definitely exposed to ortho-toluidine for at least 10 years experienced a Standardized Incidence Ratio (SIR) of 27.2 (90% CI = 11.8–53.7). The other major exposure was to aniline, which significant epidemiological studies have failed to confirm as a human carcinogen. In retrospect, studies by G. F. Rubino, G. Scansetti, G. Piolatto ((1982) Environ. Res. 27, 241–254) and M. J. Stasik ((1988) Int. Arch. Occup. Environ. Health 60, 21–24) also support the hypothesis that ortho-toluidine is a human bladder carcinogen. Animal studies of both ortho-toluidine and its possible confounders in these epidemiological investigations further confirm this hypothesis. When evaluated in a suitably comprehensive way, according to the traditional standards for assessing causality outlined by A. B. Hill ((1977) A Short Textbook of Medical Statistics, pp. 288–294, Lippincott, Philadelphia) the evidence that ortho-toluidine causes human bladder cancer has become much more conclusive. In this case, animal tests have proven a good predictor of human carcinogenicity.     

Prostaglandin inhibition prevents the fall in pulmonary vascular resistance as a result of rhythmic distension of the lungs in fetal lambs

Prostaglandins (PG) are vasoactive factors involved in the regulation of pulmonary vascular resistance at birth. However, their physiologic importance is unclear. We hypothesized that PG are important regulators of pulmonary vascular resistance during static and rhythmic distension of the lungs. To test this hypothesis, we studied seven near-term fetal lambs treated with meclofenamate (a PG synthetase inhibitor) and six controls. The fetal lambs were instrumented on a long-term basis with vascular catheters to measure pulmonary arterial pressures, left atrial pressures, and pulmonary blood flow (radionuclide-labeled microsphere method). The fetal airway was intubated, and the ductus arteriosus wall was infiltrated with formalin to assure full patency during the study period. Pulmonary vascular resistance was calculated during baseline and during sequential in utero static distension of the fetal lungs, rhythmic distension, and ventilation with oxygenation. We found that during rhythmic distension, inhibition of PG synthesis abolished the 4-fold decrease in pulmonary vascular resistance seen in the control group. In contrast, during static distension, pulmonary vascular resistance did not change in either group, and during ventilation with oxygenation, pulmonary vascular resistance decreased 12-fold in both groups. We conclude that PG are important regulators of pulmonary vascular resistance during rhythmic distension but are not essential for the regulation of pulmonary vascular resistance during static distension or during ventilation with oxygenation.     

Cervical Anterior Spinal Cord Infarction

Spinal cord infarction or ischemia predominates in the thoracic region, less so in the cervical and lumbar regions. Different etiological factors have been implicated in anterior spinal artery syndrome. Magnetic resonance imaging (MRI) allows in vivo imaging of spinal cord disease, including infarction. A 31-yearold, previously healthy man had an acute onset of interscapular pain, followed by rapid development of quadriparesis associated with paresthesias and mild bladder dysfunction. Initial MRI of the cervicothoracic region demonstrated normal findings. A repeat study obtained 6 days later showed marked increase in the cervical cord size, especially at the C6-7 level. On the T2-weighted sagittal series and after gadolinium injection, increased signal in the anterior portions of the cord extending from C-4 to the T2-3 interspace was noted. This was most prominent at the C-6 and C-7 levels. The coronal views revealed abnormal high signal in the region of the anterior horns of the gray matter, a finding that is recognized as an “owl's eyes” pattern. Because the MRI changes of cerebral infarction may succeed a clinical event by hours or days, accurate diagnosis may require delayed or repeated studies. This report suggests that the diagnosis of spinal cord disease requires a similar evaluation.     

Prodromal frontal/executive dysfunction predicts incident dementia in Parkinson's disease.

To identify the cognitive characteristics predictive of incident dementia in Parkinson's disease (PD), we examined the baseline neuropsychological profiles of 18 initially non-demented patients with PD who met diagnostic criteria for dementia (PDD) at one-year follow-up. PDD participants' baseline neuropsychological test scores were compared to the baseline performance of 18 patients with PD who did not meet criteria for dementia at one-year follow-up (PDND) and 18 normal controls (NC). The three groups were matched on baseline demographic and disease variables. Relative to the PDND group, the incident PDD participants demonstrated significantly poorer performance on digits backward (Wechsler Memory Scale-Revised), word list learning and recognition (California Verbal Learning Test), and perseverative errors on the Wisconsin Card Sorting Test. Each of these baseline neuropsychological variables exhibited adequate diagnostic classification accuracy in predicting PDD and PDND group membership at follow-up. These results suggest that subtle frontal/executive dysfunction is evident during the immediate PDD prodrome and may be of prognostic value in identifying PD patients at risk for dementia. Accordingly, neuropsychological evaluation may facilitate early identification of PDD and thereby inform appropriate dispositional planning.