Effect of temperature on the breakthrough of a charcoal tube during vinyl chloride monomer sampling.

This study evaluated the effects of temperature on breakthrough of two standard collection media at various concentrations during vinyl chloride monomer (VCM) sampling. The National Institute for Occupational Safety and Health (NIOSH) and Occupational Safety and Health Administration (OSHA) methods were evaluated. To determine whether breakthrough of VCM would occur at the extremes of exposure and temperature that might be encountered in some workplaces, air samples containing 4 ppm (10.24 mg/m3), 8 ppm (20.45 mg/m3), 16 ppm (40.98 mg/m3), and 32 ppm (81.80 mg/m3) of VCM were collected at temperatures of 4, 22, and 40 degrees C. Five liters of air was sampled at the rate of 0.05 L/min for 100 min using the activated charcoal tube recommended by NIOSH. A second tube was added to the sampling train to collect any VCM that might not have been absorbed in the first tube. To collect VCM air samples by the OSHA method, two carbon molecular sieve tubes were connected serially and 3 L of air was sampled at the rate of 0.05 L/min for 60 min. A gas chromatograph with a flame ionization detector and ultra 2 capillary column was used to analyze VCM. Significant breakthrough was found when sampling at higher temperatures with the NIOSH method. No breakthrough was found when samples were collected using the OSHA media at different temperatures and concentrations. Therefore, under hot ambient conditions (>22 degrees C), the possibility of breakthrough should be considered when sampling VCM by the NIOSH method.

Mental symptoms in Parkinson's disease are important contributors to caregiver distress.

OBJECTIVE: To determine the emotional and social distress of caring for a patient with Parkinson's disease and to explore the impact of motor and mental symptoms in subjects with Parkinson's disease on their caregivers' situation. DESIGN: Cross-sectional, population-based study using self-report questionnaires to measure caregiver distress and rating scales to assess patient symptomatology. SETTING: Neurology and old age psychiatry services in Stavanger, Norway. SUBJECTS: Caregivers of 94 home-dwelling patients with Parkinson's disease. Two control groups (patients with diabetes mellitus and healthy elderly). OUTCOME MEASURES: Measures of social and emotional distress in caregivers, including the Relative Stress Scale, Beck Depression Inventory and the General Health Questionnaire. RESULTS: Caregivers, in particular spouses, had more severe depression and a higher proportion reporting tiredness, sadness and less satisfaction with life compared with healthy elderly subjects. Using linear regression analysis, patient predictors of caregiver distress were depression, functional and cognitive impairment, agitation, aberrant motor behaviour and delusions. CONCLUSIONS: Caring for a spouse with Parkinson's disease is associated with emotional and social distress, underlining the importance of also assessing the needs of carers. Mental symptoms of parkinsonian patients were the most consistent and powerful predictors of caregiver distress, suggesting that identification and treatment of mental symptoms may reduce distress in caregivers of subjects with Parkinson's disease.

Range of neuropsychiatric disturbances in patients with Parkinson's disease.

OBJECTIVES: Disturbances of cognition and emotion are common in patients with Parkinson's disease. Most previous studies of psychopathology in Parkinson's disease have focused on a single psychiatric diagnosis or condition. The objective of this study was to describe the range of neuropsychiatric symptoms in a representative sample of patients with Parkinson's disease. METHODS: The sample of 139 patients was drawn from an epidemiological study of Parkinson's disease in Rogaland county, Norway, and represented 93% of those who had survived during the 4 years since the initial assessment. The diagnosis of Parkinson's disease was based on published criteria. Neuropsychiatric symptoms were assessed using the neuropsychiatric inventory, a caregiver based structured interview, which assesses severity and frequency of 10 psychiatric symptoms present during the past month. RESULTS: At least one psychiatric symptom was reported in 61% of the sample. The most common behaviours were depression (38%) and hallucinations (27%), and the least common symptoms were euphoria and disinhibition. The highest mean scores were found for depression, apathy, and hallucinations. Factor analysis showed that hallucinations, delusions, and irritability clustered into one factor, and apathy and anxiety constituted another factor. Psychiatric symptoms were more common among patients living in nursing homes compared with home dwelling patients, and correlated with stage of disease and cognitive impairment, but not with age or duration of disease. No relation to left or right sided parkinsonism was found. CONCLUSION: This study emphasises the importance of psychiatric symptoms in Parkinson's disease, which were present in most patients. Clinicians should focus on the emotional and cognitive disturbances in addition to the motor manifestations of the disease.

Olanzapine for psychosis in patients with Parkinson's disease with and without dementia.

Twenty-one patients with Parkinson's disease and psychosis were included in an open-label 8-week trial of olanzapine. Eight subjects had dementia. Six subjects (29%) discontinued treatment prematurely because of drowsiness. Delusions and hallucinations improved significantly, and 80% were rated as much or very much improved. There was no worsening of parkinsonism or cognition.

Simultaneous analysis of urinary 2-thiothiazolidine-4-carboxylic acid and thiocarbamide as a biological exposure index for carbon disulfide exposure.

The objectives of this study were to develop optimal analytic methods for detecting urinary 2-thiothiazolidine-4-carboxylic acid (TTCA) and thiocarbamide simultaneously and to evaluate the usefulness of these metabolites to a biological exposure index (BEI) for carbon disulfide (CS2) exposure. For this experiment, synthesized TTCA and thiocarbamide were used. The synthesized TTCA was identified by infrared spectrophotometer, nuclear magnetic resonance spectrometer and thin layer chromatography. The recovery rates of both metabolites were calculated to find the optimum analytical method. The amounts of urinary TTCA and thiocarbamide were measured by using an ultraviolet detector connected to high performance liquid chromatography (HPLC) after the administration of CS2 (350, 700 mg/kg) into Sprague-Dawley rats intraperitoneally. The maximum absorbance wave lengths for TTCA and thiocarbamide were 272 and 236 nm, respectively. Ethyl acetate extraction with NaCl as a salting-out reagent was used as a simultaneous extraction method for these metabolites. HPLC conditions for these metabolites included using a NH2 column, 50 mM KH2PO4: acetonitrile (85:15) and pH 3. Excreted amounts of urinary TTCA and thiocarbamide were increased significantly following CS2 administration. TTCA, which was already adopted as a BEI for CS2 by the American Conference of Governmental Industrial Hygienists (ACGIH), seems to be a more useful BEI for CS2 exposure than thiocarbamide. However further studies are needed to increase analytical efficiency before thiocarbamide can be adopted as a BEI and to apply this analytic method for simultaneous analysis of these metabolites in workers exposed to CS2.