EFFECT OF CAFFEINE-DEXTROSE ON FlXATlONAL AND READING EFFICIENCY

Fourteen male optometry students were tested under control conditions (taking neither stimulant nor placebo) on reading comprehension, duration (speed), total number of fixations, and span of fixation. They then were divided randomly into two equal groups. One group ingested two tablets, each containing 200 mg caffeine alkaloid and 150 mg of dextrose; the other, two placebo tablets containing sugar and pepper. Results showed no difference between the two control groups, indicating about equal base for initiating the experimental procedure, and no difference between control and placebo, reflecting the ineffectiveness of this placebo as a stimulant. Significant difference between control and caffeine-dextrose appeared in three of the four efficiency measures, implying a need for still higher dosage to bring out significant improvement in duration. Significant difference between the two experimental mean-percent improvements indicated that caffeine-dextrose, at the present composition and dosage, does enhance the fixational and reading efficiency.     

The enantiomers of SK&F 83566, a new selective D-1 dopamine antagonist, stereospecifically block stereotyped behaviour induced by apomorphine and by the selective D-2 agonist RU 24213

The non-selective dopamine receptor agonist apomorphine and the selective D-2 receptor agonist RU24213 each induced a typical syndrome of stereotyped behaviour characterised by sniffing and locomotion. The syndrome and its associated behaviours induced by each agonist were dose-dependently antagonised by pretreatment with the R- but not with the S-enantiomer of the benzazepine SK&F 83566. R- but not S-SK&F 83566 stereoselectively blocks D-1 receptors with high affinity, while the enantiomers have a very weak affinity for D-2 receptors which shows negligible stereoselectivity. Therefore, enantioselective blockade of brain D-1 receptors appears able to influence the expression of behaviours initiated by D-2 receptor stimulation.     

Longitudinal change in 99mTcHMPAO cerebral perfusion SPECT in Parkinson's disease over one year

BACKGROUND: Brain perfusion deficits have been reported previously in subjects with Parkinson's disease in comparison with healthy controls. OBJECTIVE: To carry out a longitudinal study of perfusion in patients with Parkinson's disease and controls to find areas showing a reduction in perfusion over one year. METHODS: Two HMPAO cerebral perfusion scans were acquired one year apart in 30 subjects with Parkinson's disease (mean (SD) age, 76 (5) years) and 34 healthy comparison subjects (76 (7) years). Scans were normalised to the mean intensity in the cerebellum. RESULTS: Using SPM99 within groups to investigate regions that showed a decrease in perfusion between scans, it was found that in Parkinson's disease subjects but not controls there was a significant cluster in the frontal lobe (Brodmann area 10) where perfusion decreased over the year. CONCLUSIONS: The progressive frontal perfusion deficits in Parkinson's disease are consistent with results from previous structural and neuropsychological studies suggesting frontal lobe involvement and executive dysfunction even in early Parkinson's disease.     

The role of levodopa in the management of dementia with Lewy bodies

BACKGROUND: One of the core clinical features of dementia with Lewy bodies (DLB) is extrapyramidal syndrome (EPS). Levodopa is currently the gold standard oral therapy for Parkinson's disease (PD), but its use in DLB has been tempered by concerns of exacerbating neuropsychiatric symptoms. AIM: To assess the efficacy and tolerability of L-dopa in managing EPS in DLB and to compare the motor response with that seen in PD and PD with dementia (PDD). METHOD: EPS assessment consisted of the Unified Parkinson's Disease Rating Scale, motor subsection (UPDRS III), and finger tapping and walking tests. Patients with DLB were commenced on L-dopa. After 6 months, patients were examined in the "off" state, given L-dopa and assessed for motor responses. Identical assessments were performed in patients with PD and PDD also receiving L-dopa. RESULTS: Acute L-dopa challenge in 14 DLB patients yielded a mean 13.8% (p = 0.02) improvement in UPDRS III score, compared with 20.5% in PD (n = 28, p < 0.0001) and 23% in PDD (n = 30, p<0.0001) respectively. Finger tapping scores increased (12.3% v 20% and 23%), while walking test scores decreased (32% v 41% and 67%). Of the DLB patients, 36% were classified as "responders" on L-dopa challenge, compared with 70% of the PDD and 57% of the PD patients. Nineteen DLB patients were treated for 6 months with L-dopa (mean daily dose 323 mg). Two withdrew prematurely with gastrointestinal symptoms and two with worsening confusion. CONCLUSION: L-dopa was generally well tolerated in DLB but produced a significant motor response in only about one third of patients. Younger DLB cases were more likely to respond to dopaminergic treatment.     

Sensory abnormalities in unaffected relatives in familial adult-onset dystonia

Somatosensory abnormalities are found in adult-onset primary torsion dystonia (PTD). Therefore we assessed spatial discrimination thresholds (SDT), a measure of spatial acuity, in four multiplex families with adult-onset PTD. In family members aged 20 to 45 years vs controls (mean + 2.5 SD), abnormal SDTs were found in four of five affected with adult-onset PTD and in 12 of 49 unaffected relatives. Sensory abnormalities may be an endophenotype, possibly expressed later as adult-onset PTD.     

Survival after resection for lung cancer is the outcome that matters

BACKGROUND: Lung cancer is the leading cause of cancer mortality in the United States. Stage-specific survival is well documented in national data sets; however, there remains limited recording of longitudinal survival in individual centers. METHODS: The VistA Surgery Package was employed to list operations performed by the thoracic surgery service at one Veterans Administration (VA) Medical Center. RESULTS: During a period of 107 months, 416 thoracic operations were performed, 211 of them for lung cancer. Stage distribution was 66% stage I, 18% stage II, 12% stage III, and 4% stage IV. During follow-up, 102 patients died, 57 of them from disease-specific causes. Median survival was 39 months for stage I. Disease-specific median survival was 83 months for stage I, and 5-year survival was 52% (72% for stage IA and 32% for stage IB). CONCLUSIONS: Pulmonary resection offers high disease-free survival for early-stage lung cancer. Decentralized hospital computer programming (DHCP) allows individual oncology programs to reliably measure survival. Use of this important outcome measure in quality improvement programs facilitates realistic counseling of patients and meaningful assessments of practice effectiveness.