A model for azinphosmethyl attenuation and movement in a Michigan orchard ecosystem: II. Parameterization of a field-based model

Residue data from field samples were used to parameterize a model for azinphosmethyl attenuation and movement in an orchard ecosystem. Rates of attenuation within, and movement between, specified orchard compartments were determined under various rainfall regimes. The output of this model was structured to allow the estimation of the time course of azinphosmethyl exposure to ground-dwelling invertebrates. Root mean squared errors for the comparison of the model predictions with an independent set of residue data indicated good prediction of azinphosmethyl fate within the tree, grass-broadleaves layers, and soil layers. Prediction of pesticide dynamics within the litter-moss was much more difficult. Model predictions estimate that under dry conditions 25% of the daily loss of azinphosmethyl from the orchard trees is due to movement to other parts of the orchard. Greater movement is predicted under rainfall conditions.     

Cystometry and mictometry as tools in diagnosing neurogenic impotence

Thirty-six males with erective impotence underwent neurological and urological examinations. Six of the patients were known to have a neurological disorder at the time of referral (four multiple sclerosis, one myelomeningocele, one diabetic polyneuropathy). Four further cases of neurological disorders were found (one multiple sclerosis, one myelopathy of unknown cause, one Shy-Drager syndrome, one sequelae of sacral herpes zoster). Five of these 10 patients gave a history of urinary troubles, but in all of them objective signs of bladder dysfunction were found at cystometry and/or mictometry. Among the 26 patients with impotence and no indication of a neurological disorder all invariably had normal cystometrograms, though some had abnormal mictiograms, probably due to local urological disorders.
A neurological examination should be included in the evaluation of patients with erective impotence. Cystometry and mictometry may be of value by giving additional indications that the impotence is neurogenic. This is explained by the fact that the anatomical structures regulating sexual function lie close to corresponding structures regulating bladder function at the spinal level.     

An Unnecessary Case of Paraffin Oil Pneumonia

ABSTRACT A 64-year-old woman died after 12 years of progressive pulmonary disease which was initially diagnosed as sarcoidosis but later correctly identified as mineral oil pneumonia due to insufflation of paraffin instilled as nasal drops. In view of the potential damaging effect of liquid paraffin on the lungs, the current indications for its use must be strongly questioned.     

First clinical experience with beta-trace protein (prostaglandin D synthase) as a marker for perilymphatic fistula

A diagnosis of perilymphatic fistula is still controversial. Recently, a case report indicated that beta-trace protein (prostaglandin D synthase) might be a potential marker for perilymphatic fluid. In this multicentre clinical case series study beta-trace protein was used as a marker for perilymphatic fluid fistula. Fifteen fluid samples were collected during diagnostic tympanoscopy. In addition, five samples were collected from patients with tympanic membrane perforation for use as as negative controls. Samples were obtained using precision glass capillaries and were analysed for beta-trace protein using laser nephelometry. The diagnosis of perilymphatic fistula was defined by the patient's history, the audiological and vestibular investigation and the findings at tympanoscopy. The cut-off level of beta-trace protein for perilymph-positive samples was chosen at 1.11 mg/l. The sensitivity and specificity were calculated using a 2 x 2 contingency table. There was no false positive result, but in two cases a false negative result was found. The specificity was 1 and the sensitivity was 0.81. The material of this first clinical study is small owing to the rarity of patients undergoing diagnostic tympanoscopy for perilymphatic fluid fistula. However, according to these preliminary results beta-trace protein might be a promising marker in the diagnosis of perilymphatic fluid fistulas.     

The influence of genetic variation in oxidative stress genes on human noise susceptibility

Noise induced hearing loss (NIHL) is a complex disease caused by an interaction between genetic and environmental factors. Damage in the cochlea as a result of noise exposure appears to be mediated by reactive oxygen species (ROS). To investigate whether genetic variation in the human protective antioxidant system is associated with high or low susceptibility to NIHL, genetic polymorphisms derived from genes involved in the oxidative stress response were analysed in the 10% most susceptible and 10% most resistant extremes of 1200 Swedish noise-exposed workers. The genetic polymorphisms included 2 deletion polymorphisms for the GSTM1 and GSTT1 gene, and 14 SNPs derived from the CAT, SOD, GPX, GSR and GSTP1 genes. No significant differences were found between susceptible and resistant groups, providing no support for a major role of genetic variation of antioxidant enzymes in the susceptibility to NIHL.     

Are endophenotypes based on measures of executive functions useful for molecular genetic studies of ADHD?

BACKGROUND: Behavioral genetic studies provide strong evidence that attention-deficit/hyperactivity disorder (ADHD) has a substantial genetic component. Yet, due to the complexity of the ADHD phenotype, questions remain as to the specific genes that contribute to this condition as well as the pathways from genes to behavior. Endophenotypes, or phenotypes that are more closely linked to the neurobiological substrate of a disorder, offer the potential to address these two issues simultaneously (Freedman, Adler, & Leonard, 1999). Thus far, potential endophenotypes for ADHD have not been systematically studied. METHOD: The current paper reviews evidence supporting the use of deficits on neurocognitive measures of executive functions for this purpose. RESULTS: Such deficits are a correlate of ADHD and show preliminary evidence of heritability and association with relevant candidate genes. Nonetheless, studies that have assessed the familial and genetic overlap of neurocognitive impairments with ADHD have yielded inconsistent results. CONCLUSIONS: In order for executive function deficits to be used as an endophenotype for ADHD, we recommend greater attention to the neurocognitive heterogeneity of this disorder and to the precision of measurement of the neuropsychological tests employed. We also discuss empirical strategies that may be necessary to allow such research to progress prior to full resolution of the pathophysiological basis of ADHD.     

Several genes in the extended human MHC contribute to predisposition to autoimmune diseases

Autoimmune diseases, such as type 1 diabetes, rheumatoid arthritis, psoriasis and systemic lupus erythematosus, affect approximately 4% of the population in industrialized countries, and are characterized by an immune-mediated destruction of autologous cells and/or tissues. More knowledge is needed to prevent and treat this large group of diseases. Unravelling the genetic predisposing factors is important in this respect, and large research efforts have been initiated to reach this goal. The human MHC, also called the human leukocyte antigen (HLA) complex, is known to harbour major genetic determinants for autoimmune diseases. For several autoimmune diseases certain classical HLA class II and/or class I genes are strongly associated with disease. As a result of recent systematic screening studies additional genes and regions in the MHC, including the extended MHC, are now known to contribute to the predisposition.