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.     

Spigelian Hernia

We report on the evolution in concept and techniques that allowed us to improve the treatment of spigelian hernia, operable in day surgery in 90% of cases and through a preperitoneal and recently a preperitoneal and subfascial prosthetic repair (PHS). Background data. We propose an innovative use of the PHS mesh for spigelian hernia repair. With this new implementation, we confront the standard surgical technique and its postoperative period. Methods. From January 1992 to March 2004, we performed 2,500 hernia surgical operations, including 32 spigelian hernia repairs (1.3% of total case series). The first surgical approach used for 20 of these 32 patients (62.5% of total spigelian hernias), all electively operated on, was a classical preperitoneal repair (Wantz), performed when possible by size of defect and weight (Body Mass Index) of the patient, under local anesthesia and on a day-surgery basis. Our new modified technique takes place through the insertion of a PHS large-type mesh, whose bottom underlay portion lies flat in the preperitoneal space with the connector obliterating the hernial orifice and with the overlay portion lying on the internal oblique muscle, covered by the aponeurosis of the external oblique muscle. Results. Our modification to the classical technique consisted only in the application of a product, such as the PHS, in a hernia defect, which presented with an orifice of the size of the connector and, therefore, was easily repairable with the use of the PHS device. This approach is easier than the preperitoneal approach, its always suitable for local anaesthesia, and it gives a more comfortable postoperative period. The surgical approach may be performed completely in day surgery. Conclusions. We believe that spigelian hernia surgical repair should always be performed by means of a preperitoneal prosthesis under local anaesthesia when the patients clinical and physical conditions allow for it, always in day surgery, and using the PHS mesh when the hernia defect size fits with the connector diameter. This last possibility seems to be easier and more comfortable for the patient in the postoperative period.     

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.