ABSTRACT
A method to establish two experimental corky ringspot disease (CRS) plots that had no prior CRS history is described. CRS is a serious disease of potato in the Pacific Northwest caused by tobacco rattle virus (TRV) and transmitted primarily by Paratrichodorus allius. 'Samsun NN' tobacco seedlings were inoculated with viruliferous P. allius in the greenhouse before they were transplanted into the field soil at the rate of 3,000 plus seedlings/ha. Care was taken to keep soil around plants in the greenhouse and transplants in the field moist to avoid vector mortality. The vector population in the soil of one of the fields was monitored by extraction, examination under microscope and bioassay on tobacco seedlings to ascertain that they were virus carriers. Presence of virus in tobacco bioassay plants was determined by visual symptoms on tobacco leaves and by testing leaves and roots using ELISA. Although TRV transmission was rapid, there was loss of infectivity in the first winter which necessitated a re-inoculation. After two years of planting infected tobacco seedlings, 100% of soil samples collected from this field contained viruliferous P. allius. In the second field, all five commercial potato cultivars, known to be susceptible, expressed symptoms of CRS disease indicating that the procedure was successful.
ABSTRACT
Using recently refined diagnostic criteria, the authors hypothesized that the frequent touching of others by a 16-year-old male adolescent with Tourette's syndrome was a compulsion and not a tic. Consistent with the study's hypothesis, the authors applied exposure and response prevention, a procedure empirically supported for treatment of compulsions but not for tics, to the touching. Results showed a significant decrease in touching attempts, overt anxiety, and subjective anxiety across time.
Subject(s)
Behavior Therapy/methods , Compulsive Behavior/therapy , Obsessive-Compulsive Disorder/complications , Obsessive-Compulsive Disorder/therapy , Tourette Syndrome/complications , Adolescent , Humans , Male , Tourette Syndrome/therapy , Treatment OutcomeABSTRACT
This study was undertaken to evaluate teratogenesis associated with early weekly ethanol exposure followed by later gestational abstinence. Ethanol, 1.8 gm/kg, was orally administered weekly to gravid nonhuman primates (Macaca nemestrina) for the first 3, 6, or the entire 24 weeks of pregnancy. Control animals received weekly sucrose solution as did the 3- and 6-week cohort animals in subsequent weeks. Thirty-five viable infants were assessed for growth, malformations, and behavioral and cognitive dysfunction. Animals in the 6-week and 24-week cohorts were uniformly abnormal in behavior and inconsistently abnormal in physical development relative to the control animals. Animals in the 3-week cohort were equivocally normal. These results demonstrate ethanol's capacity to produce behavioral teratogenesis (brain dysfunction) in isolation from physical anomalies in the rest of the body. The results strongly suggest that binge drinking in the first 6 to 8 weeks of pregnancy (a period when women may not know that they are pregnant), followed by later gestational abstinence, is as dangerous to the fetus as exposure throughout gestation.
Subject(s)
Behavior, Animal/drug effects , Cognition/drug effects , Ethanol/toxicity , Fetus/drug effects , Abnormalities, Drug-Induced/etiology , Animals , Female , Growth/drug effects , Macaca nemestrina , Male , Memory/drug effects , Motor Skills/drug effectsSubject(s)
Dog Diseases/etiology , Pyloric Stenosis/veterinary , Vomiting/veterinary , Animals , Dogs , Male , Pyloric Stenosis/etiology , Vomiting/etiologyABSTRACT
Regan Contrast Sensitivity Letter Charts were used to assess the effects of reduced contrast and luminance on visual acuity in retinitis pigmentosa (RP) patients. Letter acuity was measured monocularly in 17 RP patients and in 14 age-similar normals using charts of three different contrast levels presented at each of four levels of illumination. Despite visual acuities of 20/40 or better under standard clinical test conditions, an appreciable number of RP patients were unable to identify any letters on the intermediate- and/or low-contrast Regan charts. For example, even at the recommended test luminance, 5 patients could not read any letters on the intermediate (11%) contrast chart, and 9 could not be scored on the low (4%) contrast chart. Consequently, the Regan charts were found to have limited usefulness in quantifying the exact extent of visual impairment in this group of RP patients. Nevertheless, our results document the degree of visual acuity loss that can be experienced by RP patients under conditions of low contrast and luminance.
